Merge pull request #1853 from Gustav-Simonsson/libsecp256k1_update

Update libsecp256k1, Go wrapper and tests
pull/1881/head
Jeffrey Wilcke 9 years ago
commit f466243417
  1. 10
      crypto/crypto.go
  2. 41
      crypto/secp256k1/libsecp256k1/.gitignore
  3. 62
      crypto/secp256k1/libsecp256k1/.travis.yml
  4. 0
      crypto/secp256k1/libsecp256k1/COPYING
  5. 47
      crypto/secp256k1/libsecp256k1/Makefile.am
  6. 0
      crypto/secp256k1/libsecp256k1/README.md
  7. 0
      crypto/secp256k1/libsecp256k1/TODO
  8. 0
      crypto/secp256k1/libsecp256k1/autogen.sh
  9. 64
      crypto/secp256k1/libsecp256k1/configure.ac
  10. 547
      crypto/secp256k1/libsecp256k1/include/secp256k1.h
  11. 30
      crypto/secp256k1/libsecp256k1/include/secp256k1_ecdh.h
  12. 110
      crypto/secp256k1/libsecp256k1/include/secp256k1_recovery.h
  13. 173
      crypto/secp256k1/libsecp256k1/include/secp256k1_schnorr.h
  14. 0
      crypto/secp256k1/libsecp256k1/libsecp256k1.pc.in
  15. 0
      crypto/secp256k1/libsecp256k1/obj/.gitignore
  16. 32
      crypto/secp256k1/libsecp256k1/src/basic-config.h
  17. 22
      crypto/secp256k1/libsecp256k1/src/bench.h
  18. 53
      crypto/secp256k1/libsecp256k1/src/bench_ecdh.c
  19. 62
      crypto/secp256k1/libsecp256k1/src/bench_internal.c
  20. 29
      crypto/secp256k1/libsecp256k1/src/bench_recover.c
  21. 73
      crypto/secp256k1/libsecp256k1/src/bench_schnorr_verify.c
  22. 26
      crypto/secp256k1/libsecp256k1/src/bench_sign.c
  23. 32
      crypto/secp256k1/libsecp256k1/src/bench_verify.c
  24. 22
      crypto/secp256k1/libsecp256k1/src/ecdsa.h
  25. 91
      crypto/secp256k1/libsecp256k1/src/ecdsa_impl.h
  26. 28
      crypto/secp256k1/libsecp256k1/src/eckey.h
  27. 44
      crypto/secp256k1/libsecp256k1/src/eckey_impl.h
  28. 31
      crypto/secp256k1/libsecp256k1/src/ecmult.h
  29. 12
      crypto/secp256k1/libsecp256k1/src/ecmult_const.h
  30. 260
      crypto/secp256k1/libsecp256k1/src/ecmult_const_impl.h
  31. 43
      crypto/secp256k1/libsecp256k1/src/ecmult_gen.h
  32. 205
      crypto/secp256k1/libsecp256k1/src/ecmult_gen_impl.h
  33. 389
      crypto/secp256k1/libsecp256k1/src/ecmult_impl.h
  34. 53
      crypto/secp256k1/libsecp256k1/src/field.h
  35. 24
      crypto/secp256k1/libsecp256k1/src/field_10x26.h
  36. 68
      crypto/secp256k1/libsecp256k1/src/field_10x26_impl.h
  37. 22
      crypto/secp256k1/libsecp256k1/src/field_5x52.h
  38. 0
      crypto/secp256k1/libsecp256k1/src/field_5x52_asm_impl.h
  39. 63
      crypto/secp256k1/libsecp256k1/src/field_5x52_impl.h
  40. 0
      crypto/secp256k1/libsecp256k1/src/field_5x52_int128_impl.h
  41. 32
      crypto/secp256k1/libsecp256k1/src/field_impl.h
  42. 74
      crypto/secp256k1/libsecp256k1/src/gen_context.c
  43. 141
      crypto/secp256k1/libsecp256k1/src/group.h
  44. 632
      crypto/secp256k1/libsecp256k1/src/group_impl.h
  45. 2
      crypto/secp256k1/libsecp256k1/src/hash.h
  46. 12
      crypto/secp256k1/libsecp256k1/src/hash_impl.h
  47. 0
      crypto/secp256k1/libsecp256k1/src/java/org/bitcoin/NativeSecp256k1.java
  48. 0
      crypto/secp256k1/libsecp256k1/src/java/org_bitcoin_NativeSecp256k1.c
  49. 0
      crypto/secp256k1/libsecp256k1/src/java/org_bitcoin_NativeSecp256k1.h
  50. 9
      crypto/secp256k1/libsecp256k1/src/modules/ecdh/Makefile.am.include
  51. 54
      crypto/secp256k1/libsecp256k1/src/modules/ecdh/main_impl.h
  52. 75
      crypto/secp256k1/libsecp256k1/src/modules/ecdh/tests_impl.h
  53. 9
      crypto/secp256k1/libsecp256k1/src/modules/recovery/Makefile.am.include
  54. 156
      crypto/secp256k1/libsecp256k1/src/modules/recovery/main_impl.h
  55. 249
      crypto/secp256k1/libsecp256k1/src/modules/recovery/tests_impl.h
  56. 11
      crypto/secp256k1/libsecp256k1/src/modules/schnorr/Makefile.am.include
  57. 164
      crypto/secp256k1/libsecp256k1/src/modules/schnorr/main_impl.h
  58. 20
      crypto/secp256k1/libsecp256k1/src/modules/schnorr/schnorr.h
  59. 207
      crypto/secp256k1/libsecp256k1/src/modules/schnorr/schnorr_impl.h
  60. 175
      crypto/secp256k1/libsecp256k1/src/modules/schnorr/tests_impl.h
  61. 28
      crypto/secp256k1/libsecp256k1/src/num.h
  62. 2
      crypto/secp256k1/libsecp256k1/src/num_gmp.h
  63. 38
      crypto/secp256k1/libsecp256k1/src/num_gmp_impl.h
  64. 0
      crypto/secp256k1/libsecp256k1/src/num_impl.h
  65. 104
      crypto/secp256k1/libsecp256k1/src/scalar.h
  66. 2
      crypto/secp256k1/libsecp256k1/src/scalar_4x64.h
  67. 79
      crypto/secp256k1/libsecp256k1/src/scalar_4x64_impl.h
  68. 2
      crypto/secp256k1/libsecp256k1/src/scalar_8x32.h
  69. 90
      crypto/secp256k1/libsecp256k1/src/scalar_8x32_impl.h
  70. 40
      crypto/secp256k1/libsecp256k1/src/scalar_impl.h
  71. 513
      crypto/secp256k1/libsecp256k1/src/secp256k1.c
  72. 0
      crypto/secp256k1/libsecp256k1/src/testrand.h
  73. 2
      crypto/secp256k1/libsecp256k1/src/testrand_impl.h
  74. 1446
      crypto/secp256k1/libsecp256k1/src/tests.c
  75. 26
      crypto/secp256k1/libsecp256k1/src/util.h
  76. 196
      crypto/secp256k1/secp256.go
  77. 299
      crypto/secp256k1/secp256_test.go
  78. 32
      crypto/secp256k1/secp256k1/.travis.yml
  79. 61
      crypto/secp256k1/secp256k1/build-aux/m4/bitcoin_secp.m4
  80. 295
      crypto/secp256k1/secp256k1/include/secp256k1.h
  81. 23
      crypto/secp256k1/secp256k1/src/ecdsa.h
  82. 24
      crypto/secp256k1/secp256k1/src/eckey.h
  83. 19
      crypto/secp256k1/secp256k1/src/ecmult.h
  84. 128
      crypto/secp256k1/secp256k1/src/ecmult_gen_impl.h
  85. 302
      crypto/secp256k1/secp256k1/src/ecmult_impl.h
  86. 118
      crypto/secp256k1/secp256k1/src/group.h
  87. 434
      crypto/secp256k1/secp256k1/src/group_impl.h
  88. 93
      crypto/secp256k1/secp256k1/src/scalar.h
  89. 372
      crypto/secp256k1/secp256k1/src/secp256k1.c

@ -198,7 +198,9 @@ func Sign(hash []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) {
return nil, fmt.Errorf("hash is required to be exactly 32 bytes (%d)", len(hash))
}
sig, err = secp256k1.Sign(hash, common.LeftPadBytes(prv.D.Bytes(), prv.Params().BitSize/8))
seckey := common.LeftPadBytes(prv.D.Bytes(), prv.Params().BitSize/8)
defer zeroBytes(seckey)
sig, err = secp256k1.Sign(hash, seckey)
return
}
@ -326,3 +328,9 @@ func PubkeyToAddress(p ecdsa.PublicKey) common.Address {
pubBytes := FromECDSAPub(&p)
return common.BytesToAddress(Sha3(pubBytes[1:])[12:])
}
func zeroBytes(bytes []byte) {
for i := range bytes {
bytes[i] = 0
}
}

@ -0,0 +1,41 @@
bench_inv
bench_ecdh
bench_sign
bench_verify
bench_schnorr_verify
bench_recover
bench_internal
tests
gen_context
*.exe
*.so
*.a
!.gitignore
Makefile
configure
.libs/
Makefile.in
aclocal.m4
autom4te.cache/
config.log
config.status
*.tar.gz
*.la
libtool
.deps/
.dirstamp
build-aux/
*.lo
*.o
*~
src/libsecp256k1-config.h
src/libsecp256k1-config.h.in
src/ecmult_static_context.h
m4/libtool.m4
m4/ltoptions.m4
m4/ltsugar.m4
m4/ltversion.m4
m4/lt~obsolete.m4
src/stamp-h1
libsecp256k1.pc

@ -0,0 +1,62 @@
language: c
sudo: false
addons:
apt:
packages: libgmp-dev
compiler:
- clang
- gcc
env:
global:
- FIELD=auto BIGNUM=auto SCALAR=auto ENDOMORPHISM=no STATICPRECOMPUTATION=yes ASM=no BUILD=check EXTRAFLAGS= HOST= ECDH=no schnorr=NO RECOVERY=NO
matrix:
- SCALAR=32bit RECOVERY=yes
- SCALAR=32bit FIELD=32bit ECDH=yes
- SCALAR=64bit
- FIELD=64bit RECOVERY=yes
- FIELD=64bit ENDOMORPHISM=yes
- FIELD=64bit ENDOMORPHISM=yes ECDH=yes
- FIELD=64bit ASM=x86_64
- FIELD=64bit ENDOMORPHISM=yes ASM=x86_64
- FIELD=32bit SCHNORR=yes
- FIELD=32bit ENDOMORPHISM=yes
- BIGNUM=no
- BIGNUM=no ENDOMORPHISM=yes SCHNORR=yes RECOVERY=yes
- BIGNUM=no STATICPRECOMPUTATION=no
- BUILD=distcheck
- EXTRAFLAGS=CFLAGS=-DDETERMINISTIC
matrix:
fast_finish: true
include:
- compiler: clang
env: HOST=i686-linux-gnu ENDOMORPHISM=yes
addons:
apt:
packages:
- gcc-multilib
- libgmp-dev:i386
- compiler: clang
env: HOST=i686-linux-gnu
addons:
apt:
packages:
- gcc-multilib
- compiler: gcc
env: HOST=i686-linux-gnu ENDOMORPHISM=yes
addons:
apt:
packages:
- gcc-multilib
- compiler: gcc
env: HOST=i686-linux-gnu
addons:
apt:
packages:
- gcc-multilib
- libgmp-dev:i386
before_script: ./autogen.sh
script:
- if [ -n "$HOST" ]; then export USE_HOST="--host=$HOST"; fi
- if [ "x$HOST" = "xi686-linux-gnu" ]; then export CC="$CC -m32"; fi
- ./configure --enable-endomorphism=$ENDOMORPHISM --with-field=$FIELD --with-bignum=$BIGNUM --with-scalar=$SCALAR --enable-ecmult-static-precomputation=$STATICPRECOMPUTATION --enable-module-ecdh=$ECDH --enable-module-schnorr=$SCHNORR $EXTRAFLAGS $USE_HOST && make -j2 $BUILD
os: linux

@ -19,6 +19,8 @@ noinst_HEADERS += src/eckey.h
noinst_HEADERS += src/eckey_impl.h
noinst_HEADERS += src/ecmult.h
noinst_HEADERS += src/ecmult_impl.h
noinst_HEADERS += src/ecmult_const.h
noinst_HEADERS += src/ecmult_const_impl.h
noinst_HEADERS += src/ecmult_gen.h
noinst_HEADERS += src/ecmult_gen_impl.h
noinst_HEADERS += src/num.h
@ -43,19 +45,16 @@ pkgconfigdir = $(libdir)/pkgconfig
pkgconfig_DATA = libsecp256k1.pc
libsecp256k1_la_SOURCES = src/secp256k1.c
libsecp256k1_la_CPPFLAGS = -I$(top_srcdir)/include $(SECP_INCLUDES)
libsecp256k1_la_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/src $(SECP_INCLUDES)
libsecp256k1_la_LIBADD = $(SECP_LIBS)
noinst_PROGRAMS =
if USE_BENCHMARK
noinst_PROGRAMS += bench_verify bench_recover bench_sign bench_internal
noinst_PROGRAMS += bench_verify bench_sign bench_internal
bench_verify_SOURCES = src/bench_verify.c
bench_verify_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_verify_LDFLAGS = -static
bench_recover_SOURCES = src/bench_recover.c
bench_recover_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_recover_LDFLAGS = -static
bench_sign_SOURCES = src/bench_sign.c
bench_sign_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_sign_LDFLAGS = -static
@ -68,10 +67,44 @@ endif
if USE_TESTS
noinst_PROGRAMS += tests
tests_SOURCES = src/tests.c
tests_CPPFLAGS = -DVERIFY $(SECP_INCLUDES) $(SECP_TEST_INCLUDES)
tests_CPPFLAGS = -DVERIFY -I$(top_srcdir)/src $(SECP_INCLUDES) $(SECP_TEST_INCLUDES)
tests_LDADD = $(SECP_LIBS) $(SECP_TEST_LIBS)
tests_LDFLAGS = -static
TESTS = tests
endif
EXTRA_DIST = autogen.sh
if USE_ECMULT_STATIC_PRECOMPUTATION
CPPFLAGS_FOR_BUILD +=-I$(top_srcdir)/
CFLAGS_FOR_BUILD += -Wall -Wextra -Wno-unused-function
gen_context_OBJECTS = gen_context.o
gen_context_BIN = gen_context$(BUILD_EXEEXT)
gen_%.o: src/gen_%.c
$(CC_FOR_BUILD) $(CPPFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@
$(gen_context_BIN): $(gen_context_OBJECTS)
$(CC_FOR_BUILD) $^ -o $@
$(libsecp256k1_la_OBJECTS): src/ecmult_static_context.h
$(tests_OBJECTS): src/ecmult_static_context.h
$(bench_internal_OBJECTS): src/ecmult_static_context.h
src/ecmult_static_context.h: $(gen_context_BIN)
./$(gen_context_BIN)
CLEANFILES = $(gen_context_BIN) src/ecmult_static_context.h
endif
EXTRA_DIST = autogen.sh src/gen_context.c src/basic-config.h
if ENABLE_MODULE_ECDH
include src/modules/ecdh/Makefile.am.include
endif
if ENABLE_MODULE_SCHNORR
include src/modules/schnorr/Makefile.am.include
endif
if ENABLE_MODULE_RECOVERY
include src/modules/recovery/Makefile.am.include
endif

@ -17,25 +17,19 @@ PKG_PROG_PKG_CONFIG
AC_PATH_TOOL(AR, ar)
AC_PATH_TOOL(RANLIB, ranlib)
AC_PATH_TOOL(STRIP, strip)
AX_PROG_CC_FOR_BUILD
if test "x$CFLAGS" = "x"; then
CFLAGS="-O3 -g"
fi
AM_PROG_CC_C_O
AC_PROG_CC_C89
if test x"$ac_cv_prog_cc_c89" = x"no"; then
AC_MSG_ERROR([c89 compiler support required])
fi
case $host in
*mingw*)
use_pkgconfig=no
;;
*)
use_pkgconfig=yes
;;
esac
case $host_os in
*darwin*)
if test x$cross_compiling != xyes; then
@ -80,6 +74,14 @@ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
CFLAGS="$saved_CFLAGS"
])
saved_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -fvisibility=hidden"
AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden])
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
[ AC_MSG_RESULT([yes]) ],
[ AC_MSG_RESULT([no])
CFLAGS="$saved_CFLAGS"
])
AC_ARG_ENABLE(benchmark,
AS_HELP_STRING([--enable-benchmark],[compile benchmark (default is no)]),
@ -95,6 +97,26 @@ AC_ARG_ENABLE(endomorphism,
AS_HELP_STRING([--enable-endomorphism],[enable endomorphism (default is no)]),
[use_endomorphism=$enableval],
[use_endomorphism=no])
AC_ARG_ENABLE(ecmult_static_precomputation,
AS_HELP_STRING([--enable-ecmult-static-precomputation],[enable precomputed ecmult table for signing (default is yes)]),
[use_ecmult_static_precomputation=$enableval],
[use_ecmult_static_precomputation=yes])
AC_ARG_ENABLE(module_ecdh,
AS_HELP_STRING([--enable-module-ecdh],[enable ECDH shared secret computation (default is no)]),
[enable_module_ecdh=$enableval],
[enable_module_ecdh=no])
AC_ARG_ENABLE(module_schnorr,
AS_HELP_STRING([--enable-module-schnorr],[enable Schnorr signature module (default is no)]),
[enable_module_schnorr=$enableval],
[enable_module_schnorr=no])
AC_ARG_ENABLE(module_recovery,
AS_HELP_STRING([--enable-module-recovery],[enable ECDSA pubkey recovery module (default is no)]),
[enable_module_recovery=$enableval],
[enable_module_recovery=no])
AC_ARG_WITH([field], [AS_HELP_STRING([--with-field=64bit|32bit|auto],
[Specify Field Implementation. Default is auto])],[req_field=$withval], [req_field=auto])
@ -305,6 +327,22 @@ if test x"$use_endomorphism" = x"yes"; then
AC_DEFINE(USE_ENDOMORPHISM, 1, [Define this symbol to use endomorphism optimization])
fi
if test x"$use_ecmult_static_precomputation" = x"yes"; then
AC_DEFINE(USE_ECMULT_STATIC_PRECOMPUTATION, 1, [Define this symbol to use a statically generated ecmult table])
fi
if test x"$enable_module_ecdh" = x"yes"; then
AC_DEFINE(ENABLE_MODULE_ECDH, 1, [Define this symbol to enable the ECDH module])
fi
if test x"$enable_module_schnorr" = x"yes"; then
AC_DEFINE(ENABLE_MODULE_SCHNORR, 1, [Define this symbol to enable the Schnorr signature module])
fi
if test x"$enable_module_recovery" = x"yes"; then
AC_DEFINE(ENABLE_MODULE_RECOVERY, 1, [Define this symbol to enable the ECDSA pubkey recovery module])
fi
AC_C_BIGENDIAN()
AC_MSG_NOTICE([Using assembly optimizations: $set_asm])
@ -312,6 +350,10 @@ AC_MSG_NOTICE([Using field implementation: $set_field])
AC_MSG_NOTICE([Using bignum implementation: $set_bignum])
AC_MSG_NOTICE([Using scalar implementation: $set_scalar])
AC_MSG_NOTICE([Using endomorphism optimizations: $use_endomorphism])
AC_MSG_NOTICE([Building ECDH module: $enable_module_ecdh])
AC_MSG_NOTICE([Building Schnorr signatures module: $enable_module_schnorr])
AC_MSG_NOTICE([Building ECDSA pubkey recovery module: $enable_module_recovery])
AC_CONFIG_HEADERS([src/libsecp256k1-config.h])
AC_CONFIG_FILES([Makefile libsecp256k1.pc])
@ -321,6 +363,10 @@ AC_SUBST(SECP_TEST_LIBS)
AC_SUBST(SECP_TEST_INCLUDES)
AM_CONDITIONAL([USE_TESTS], [test x"$use_tests" != x"no"])
AM_CONDITIONAL([USE_BENCHMARK], [test x"$use_benchmark" = x"yes"])
AM_CONDITIONAL([USE_ECMULT_STATIC_PRECOMPUTATION], [test x"$use_ecmult_static_precomputation" = x"yes"])
AM_CONDITIONAL([ENABLE_MODULE_ECDH], [test x"$enable_module_ecdh" = x"yes"])
AM_CONDITIONAL([ENABLE_MODULE_SCHNORR], [test x"$enable_module_schnorr" = x"yes"])
AM_CONDITIONAL([ENABLE_MODULE_RECOVERY], [test x"$enable_module_recovery" = x"yes"])
dnl make sure nothing new is exported so that we don't break the cache
PKGCONFIG_PATH_TEMP="$PKG_CONFIG_PATH"

@ -0,0 +1,547 @@
#ifndef _SECP256K1_
# define _SECP256K1_
# ifdef __cplusplus
extern "C" {
# endif
#include <stddef.h>
/* These rules specify the order of arguments in API calls:
*
* 1. Context pointers go first, followed by output arguments, combined
* output/input arguments, and finally input-only arguments.
* 2. Array lengths always immediately the follow the argument whose length
* they describe, even if this violates rule 1.
* 3. Within the OUT/OUTIN/IN groups, pointers to data that is typically generated
* later go first. This means: signatures, public nonces, private nonces,
* messages, public keys, secret keys, tweaks.
* 4. Arguments that are not data pointers go last, from more complex to less
* complex: function pointers, algorithm names, messages, void pointers,
* counts, flags, booleans.
* 5. Opaque data pointers follow the function pointer they are to be passed to.
*/
/** Opaque data structure that holds context information (precomputed tables etc.).
*
* The purpose of context structures is to cache large precomputed data tables
* that are expensive to construct, and also to maintain the randomization data
* for blinding.
*
* Do not create a new context object for each operation, as construction is
* far slower than all other API calls (~100 times slower than an ECDSA
* verification).
*
* A constructed context can safely be used from multiple threads
* simultaneously, but API call that take a non-const pointer to a context
* need exclusive access to it. In particular this is the case for
* secp256k1_context_destroy and secp256k1_context_randomize.
*
* Regarding randomization, either do it once at creation time (in which case
* you do not need any locking for the other calls), or use a read-write lock.
*/
typedef struct secp256k1_context_struct secp256k1_context;
/** Opaque data structure that holds a parsed and valid public key.
*
* The exact representation of data inside is implementation defined and not
* guaranteed to be portable between different platforms or versions. It is
* however guaranteed to be 64 bytes in size, and can be safely copied/moved.
* If you need to convert to a format suitable for storage or transmission, use
* secp256k1_ec_pubkey_serialize and secp256k1_ec_pubkey_parse.
*
* Furthermore, it is guaranteed that identical public keys (ignoring
* compression) will have identical representation, so they can be memcmp'ed.
*/
typedef struct {
unsigned char data[64];
} secp256k1_pubkey;
/** Opaque data structured that holds a parsed ECDSA signature.
*
* The exact representation of data inside is implementation defined and not
* guaranteed to be portable between different platforms or versions. It is
* however guaranteed to be 64 bytes in size, and can be safely copied/moved.
* If you need to convert to a format suitable for storage or transmission, use
* the secp256k1_ecdsa_signature_serialize_* and
* secp256k1_ecdsa_signature_serialize_* functions.
*
* Furthermore, it is guaranteed to identical signatures will have identical
* representation, so they can be memcmp'ed.
*/
typedef struct {
unsigned char data[64];
} secp256k1_ecdsa_signature;
/** A pointer to a function to deterministically generate a nonce.
*
* Returns: 1 if a nonce was successfully generated. 0 will cause signing to fail.
* Out: nonce32: pointer to a 32-byte array to be filled by the function.
* In: msg32: the 32-byte message hash being verified (will not be NULL)
* key32: pointer to a 32-byte secret key (will not be NULL)
* algo16: pointer to a 16-byte array describing the signature
* algorithm (will be NULL for ECDSA for compatibility).
* data: Arbitrary data pointer that is passed through.
* attempt: how many iterations we have tried to find a nonce.
* This will almost always be 0, but different attempt values
* are required to result in a different nonce.
*
* Except for test cases, this function should compute some cryptographic hash of
* the message, the algorithm, the key and the attempt.
*/
typedef int (*secp256k1_nonce_function)(
unsigned char *nonce32,
const unsigned char *msg32,
const unsigned char *key32,
const unsigned char *algo16,
void *data,
unsigned int attempt
);
# if !defined(SECP256K1_GNUC_PREREQ)
# if defined(__GNUC__)&&defined(__GNUC_MINOR__)
# define SECP256K1_GNUC_PREREQ(_maj,_min) \
((__GNUC__<<16)+__GNUC_MINOR__>=((_maj)<<16)+(_min))
# else
# define SECP256K1_GNUC_PREREQ(_maj,_min) 0
# endif
# endif
# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
# if SECP256K1_GNUC_PREREQ(2,7)
# define SECP256K1_INLINE __inline__
# elif (defined(_MSC_VER))
# define SECP256K1_INLINE __inline
# else
# define SECP256K1_INLINE
# endif
# else
# define SECP256K1_INLINE inline
# endif
#ifndef SECP256K1_API
# if defined(_WIN32)
# ifdef SECP256K1_BUILD
# define SECP256K1_API __declspec(dllexport)
# else
# define SECP256K1_API
# endif
# elif defined(__GNUC__) && defined(SECP256K1_BUILD)
# define SECP256K1_API __attribute__ ((visibility ("default")))
# else
# define SECP256K1_API
# endif
#endif
/**Warning attributes
* NONNULL is not used if SECP256K1_BUILD is set to avoid the compiler optimizing out
* some paranoid null checks. */
# if defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
# define SECP256K1_WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__))
# else
# define SECP256K1_WARN_UNUSED_RESULT
# endif
# if !defined(SECP256K1_BUILD) && defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
# define SECP256K1_ARG_NONNULL(_x) __attribute__ ((__nonnull__(_x)))
# else
# define SECP256K1_ARG_NONNULL(_x)
# endif
/** Flags to pass to secp256k1_context_create. */
# define SECP256K1_CONTEXT_VERIFY (1 << 0)
# define SECP256K1_CONTEXT_SIGN (1 << 1)
/** Flag to pass to secp256k1_ec_pubkey_serialize and secp256k1_ec_privkey_export. */
# define SECP256K1_EC_COMPRESSED (1 << 0)
/** Create a secp256k1 context object.
*
* Returns: a newly created context object.
* In: flags: which parts of the context to initialize.
*/
SECP256K1_API secp256k1_context* secp256k1_context_create(
unsigned int flags
) SECP256K1_WARN_UNUSED_RESULT;
/** Copies a secp256k1 context object.
*
* Returns: a newly created context object.
* Args: ctx: an existing context to copy (cannot be NULL)
*/
SECP256K1_API secp256k1_context* secp256k1_context_clone(
const secp256k1_context* ctx
) SECP256K1_ARG_NONNULL(1) SECP256K1_WARN_UNUSED_RESULT;
/** Destroy a secp256k1 context object.
*
* The context pointer may not be used afterwards.
* Args: ctx: an existing context to destroy (cannot be NULL)
*/
SECP256K1_API void secp256k1_context_destroy(
secp256k1_context* ctx
);
/** Set a callback function to be called when an illegal argument is passed to
* an API call. It will only trigger for violations that are mentioned
* explicitly in the header.
*
* The philosophy is that these shouldn't be dealt with through a
* specific return value, as calling code should not have branches to deal with
* the case that this code itself is broken.
*
* On the other hand, during debug stage, one would want to be informed about
* such mistakes, and the default (crashing) may be inadvisable.
* When this callback is triggered, the API function called is guaranteed not
* to cause a crash, though its return value and output arguments are
* undefined.
*
* Args: ctx: an existing context object (cannot be NULL)
* In: fun: a pointer to a function to call when an illegal argument is
* passed to the API, taking a message and an opaque pointer
* (NULL restores a default handler that calls abort).
* data: the opaque pointer to pass to fun above.
*/
SECP256K1_API void secp256k1_context_set_illegal_callback(
secp256k1_context* ctx,
void (*fun)(const char* message, void* data),
const void* data
) SECP256K1_ARG_NONNULL(1);
/** Set a callback function to be called when an internal consistency check
* fails. The default is crashing.
*
* This can only trigger in case of a hardware failure, miscompilation,
* memory corruption, serious bug in the library, or other error would can
* otherwise result in undefined behaviour. It will not trigger due to mere
* incorrect usage of the API (see secp256k1_context_set_illegal_callback
* for that). After this callback returns, anything may happen, including
* crashing.
*
* Args: ctx: an existing context object (cannot be NULL)
* In: fun: a pointer to a function to call when an interal error occurs,
* taking a message and an opaque pointer (NULL restores a default
* handler that calls abort).
* data: the opaque pointer to pass to fun above.
*/
SECP256K1_API void secp256k1_context_set_error_callback(
secp256k1_context* ctx,
void (*fun)(const char* message, void* data),
const void* data
) SECP256K1_ARG_NONNULL(1);
/** Parse a variable-length public key into the pubkey object.
*
* Returns: 1 if the public key was fully valid.
* 0 if the public key could not be parsed or is invalid.
* Args: ctx: a secp256k1 context object.
* Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to a
* parsed version of input. If not, its value is undefined.
* In: input: pointer to a serialized public key
* inputlen: length of the array pointed to by input
*
* This function supports parsing compressed (33 bytes, header byte 0x02 or
* 0x03), uncompressed (65 bytes, header byte 0x04), or hybrid (65 bytes, header
* byte 0x06 or 0x07) format public keys.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_parse(
const secp256k1_context* ctx,
secp256k1_pubkey* pubkey,
const unsigned char *input,
size_t inputlen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Serialize a pubkey object into a serialized byte sequence.
*
* Returns: 1 always.
* Args: ctx: a secp256k1 context object.
* Out: output: a pointer to a 65-byte (if compressed==0) or 33-byte (if
* compressed==1) byte array to place the serialized key in.
* outputlen: a pointer to an integer which will contain the serialized
* size.
* In: pubkey: a pointer to a secp256k1_pubkey containing an initialized
* public key.
* flags: SECP256K1_EC_COMPRESSED if serialization should be in
* compressed format.
*/
SECP256K1_API int secp256k1_ec_pubkey_serialize(
const secp256k1_context* ctx,
unsigned char *output,
size_t *outputlen,
const secp256k1_pubkey* pubkey,
unsigned int flags
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Parse a DER ECDSA signature.
*
* Returns: 1 when the signature could be parsed, 0 otherwise.
* Args: ctx: a secp256k1 context object
* Out: sig: a pointer to a signature object
* In: input: a pointer to the signature to be parsed
* inputlen: the length of the array pointed to be input
*
* Note that this function also supports some violations of DER and even BER.
*/
SECP256K1_API int secp256k1_ecdsa_signature_parse_der(
const secp256k1_context* ctx,
secp256k1_ecdsa_signature* sig,
const unsigned char *input,
size_t inputlen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Serialize an ECDSA signature in DER format.
*
* Returns: 1 if enough space was available to serialize, 0 otherwise
* Args: ctx: a secp256k1 context object
* Out: output: a pointer to an array to store the DER serialization
* In/Out: outputlen: a pointer to a length integer. Initially, this integer
* should be set to the length of output. After the call
* it will be set to the length of the serialization (even
* if 0 was returned).
* In: sig: a pointer to an initialized signature object
*/
SECP256K1_API int secp256k1_ecdsa_signature_serialize_der(
const secp256k1_context* ctx,
unsigned char *output,
size_t *outputlen,
const secp256k1_ecdsa_signature* sig
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Verify an ECDSA signature.
*
* Returns: 1: correct signature
* 0: incorrect or unparseable signature
* Args: ctx: a secp256k1 context object, initialized for verification.
* In: sig: the signature being verified (cannot be NULL)
* msg32: the 32-byte message hash being verified (cannot be NULL)
* pubkey: pointer to an initialized public key to verify with (cannot be NULL)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_verify(
const secp256k1_context* ctx,
const secp256k1_ecdsa_signature *sig,
const unsigned char *msg32,
const secp256k1_pubkey *pubkey
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** An implementation of RFC6979 (using HMAC-SHA256) as nonce generation function.
* If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
* extra entropy.
*/
extern const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
/** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
extern const secp256k1_nonce_function secp256k1_nonce_function_default;
/** Create an ECDSA signature.
*
* Returns: 1: signature created
* 0: the nonce generation function failed, or the private key was invalid.
* Args: ctx: pointer to a context object, initialized for signing (cannot be NULL)
* Out: sig: pointer to an array where the signature will be placed (cannot be NULL)
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
*
* The sig always has an s value in the lower half of the range (From 0x1
* to 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
* inclusive), unlike many other implementations.
*
* With ECDSA a third-party can can forge a second distinct signature
* of the same message given a single initial signature without knowing
* the key by setting s to its additive inverse mod-order, 'flipping' the
* sign of the random point R which is not included in the signature.
* Since the forgery is of the same message this isn't universally
* problematic, but in systems where message malleability or uniqueness
* of signatures is important this can cause issues. This forgery can be
* blocked by all verifiers forcing signers to use a canonical form. The
* lower-S form reduces the size of signatures slightly on average when
* variable length encodings (such as DER) are used and is cheap to
* verify, making it a good choice. Security of always using lower-S is
* assured because anyone can trivially modify a signature after the
* fact to enforce this property. Adjusting it inside the signing
* function avoids the need to re-serialize or have curve specific
* constants outside of the library. By always using a canonical form
* even in applications where it isn't needed it becomes possible to
* impose a requirement later if a need is discovered.
* No other forms of ECDSA malleability are known and none seem likely,
* but there is no formal proof that ECDSA, even with this additional
* restriction, is free of other malleability. Commonly used serialization
* schemes will also accept various non-unique encodings, so care should
* be taken when this property is required for an application.
*/
SECP256K1_API int secp256k1_ecdsa_sign(
const secp256k1_context* ctx,
secp256k1_ecdsa_signature *sig,
const unsigned char *msg32,
const unsigned char *seckey,
secp256k1_nonce_function noncefp,
const void *ndata
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Verify an ECDSA secret key.
*
* Returns: 1: secret key is valid
* 0: secret key is invalid
* Args: ctx: pointer to a context object (cannot be NULL)
* In: seckey: pointer to a 32-byte secret key (cannot be NULL)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(
const secp256k1_context* ctx,
const unsigned char *seckey
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Compute the public key for a secret key.
*
* Returns: 1: secret was valid, public key stores
* 0: secret was invalid, try again
* Args: ctx: pointer to a context object, initialized for signing (cannot be NULL)
* Out: pubkey: pointer to the created public key (cannot be NULL)
* In: seckey: pointer to a 32-byte private key (cannot be NULL)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
const secp256k1_context* ctx,
secp256k1_pubkey *pubkey,
const unsigned char *seckey
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Export a private key in BER format.
*
* Returns: 1 if the private key was valid.
* Args: ctx: pointer to a context object, initialized for signing (cannot
* be NULL)
* Out: privkey: pointer to an array for storing the private key in BER.
* Should have space for 279 bytes, and cannot be NULL.
* privkeylen: Pointer to an int where the length of the private key in
* privkey will be stored.
* In: seckey: pointer to a 32-byte secret key to export.
* flags: SECP256K1_EC_COMPRESSED if the key should be exported in
* compressed format.
*
* This function is purely meant for compatibility with applications that
* require BER encoded keys. When working with secp256k1-specific code, the
* simple 32-byte private keys are sufficient.
*
* Note that this function does not guarantee correct DER output. It is
* guaranteed to be parsable by secp256k1_ec_privkey_import.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_export(
const secp256k1_context* ctx,
unsigned char *privkey,
size_t *privkeylen,
const unsigned char *seckey,
unsigned int flags
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Import a private key in DER format.
* Returns: 1 if a private key was extracted.
* Args: ctx: pointer to a context object (cannot be NULL).
* Out: seckey: pointer to a 32-byte array for storing the private key.
* (cannot be NULL).
* In: privkey: pointer to a private key in DER format (cannot be NULL).
* privkeylen: length of the DER private key pointed to be privkey.
*
* This function will accept more than just strict DER, and even allow some BER
* violations. The public key stored inside the DER-encoded private key is not
* verified for correctness, nor are the curve parameters. Use this function
* only if you know in advance it is supposed to contain a secp256k1 private
* key.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_import(
const secp256k1_context* ctx,
unsigned char *seckey,
const unsigned char *privkey,
size_t privkeylen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a private key by adding tweak to it.
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
* uniformly random 32-byte arrays, or if the resulting private key
* would be invalid (only when the tweak is the complement of the
* private key). 1 otherwise.
* Args: ctx: pointer to a context object (cannot be NULL).
* In/Out: seckey: pointer to a 32-byte private key.
* In: tweak: pointer to a 32-byte tweak.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
const secp256k1_context* ctx,
unsigned char *seckey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a public key by adding tweak times the generator to it.
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
* uniformly random 32-byte arrays, or if the resulting public key
* would be invalid (only when the tweak is the complement of the
* corresponding private key). 1 otherwise.
* Args: ctx: pointer to a context object initialized for validation
* (cannot be NULL).
* In/Out: pubkey: pointer to a public key object.
* In: tweak: pointer to a 32-byte tweak.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
const secp256k1_context* ctx,
secp256k1_pubkey *pubkey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a private key by multiplying it by a tweak.
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
* uniformly random 32-byte arrays, or equal to zero. 1 otherwise.
* Args: ctx: pointer to a context object (cannot be NULL).
* In/Out: seckey: pointer to a 32-byte private key.
* In: tweak: pointer to a 32-byte tweak.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
const secp256k1_context* ctx,
unsigned char *seckey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a public key by multiplying it by a tweak value.
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
* uniformly random 32-byte arrays, or equal to zero. 1 otherwise.
* Args: ctx: pointer to a context object initialized for validation
* (cannot be NULL).
* In/Out: pubkey: pointer to a public key obkect.
* In: tweak: pointer to a 32-byte tweak.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
const secp256k1_context* ctx,
secp256k1_pubkey *pubkey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Updates the context randomization.
* Returns: 1: randomization successfully updated
* 0: error
* Args: ctx: pointer to a context object (cannot be NULL)
* In: seed32: pointer to a 32-byte random seed (NULL resets to initial state)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_context_randomize(
secp256k1_context* ctx,
const unsigned char *seed32
) SECP256K1_ARG_NONNULL(1);
/** Add a number of public keys together.
* Returns: 1: the sum of the public keys is valid.
* 0: the sum of the public keys is not valid.
* Args: ctx: pointer to a context object
* Out: out: pointer to pubkey for placing the resulting public key
* (cannot be NULL)
* In: ins: pointer to array of pointers to public keys (cannot be NULL)
* n: the number of public keys to add together (must be at least 1)
* Use secp256k1_ec_pubkey_compress and secp256k1_ec_pubkey_decompress if the
* uncompressed format is needed.
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_combine(
const secp256k1_context* ctx,
secp256k1_pubkey *out,
const secp256k1_pubkey * const * ins,
int n
) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
# ifdef __cplusplus
}
# endif
#endif

@ -0,0 +1,30 @@
#ifndef _SECP256K1_ECDH_
# define _SECP256K1_ECDH_
# include "secp256k1.h"
# ifdef __cplusplus
extern "C" {
# endif
/** Compute an EC Diffie-Hellman secret in constant time
* Returns: 1: exponentiation was successful
* 0: scalar was invalid (zero or overflow)
* Args: ctx: pointer to a context object (cannot be NULL)
* Out: result: a 32-byte array which will be populated by an ECDH
* secret computed from the point and scalar
* In: point: pointer to a public point
* scalar: a 32-byte scalar with which to multiply the point
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdh(
const secp256k1_context* ctx,
unsigned char *result,
const secp256k1_pubkey *point,
const unsigned char *scalar
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
# ifdef __cplusplus
}
# endif
#endif

@ -0,0 +1,110 @@
#ifndef _SECP256K1_RECOVERY_
# define _SECP256K1_RECOVERY_
# include "secp256k1.h"
# ifdef __cplusplus
extern "C" {
# endif
/** Opaque data structured that holds a parsed ECDSA signature,
* supporting pubkey recovery.
*
* The exact representation of data inside is implementation defined and not
* guaranteed to be portable between different platforms or versions. It is
* however guaranteed to be 65 bytes in size, and can be safely copied/moved.
* If you need to convert to a format suitable for storage or transmission, use
* the secp256k1_ecdsa_signature_serialize_* and
* secp256k1_ecdsa_signature_parse_* functions.
*
* Furthermore, it is guaranteed that identical signatures (including their
* recoverability) will have identical representation, so they can be
* memcmp'ed.
*/
typedef struct {
unsigned char data[65];
} secp256k1_ecdsa_recoverable_signature;
/** Parse a compact ECDSA signature (64 bytes + recovery id).
*
* Returns: 1 when the signature could be parsed, 0 otherwise
* Args: ctx: a secp256k1 context object
* Out: sig: a pointer to a signature object
* In: input64: a pointer to a 64-byte compact signature
* recid: the recovery id (0, 1, 2 or 3)
*/
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_parse_compact(
const secp256k1_context* ctx,
secp256k1_ecdsa_recoverable_signature* sig,
const unsigned char *input64,
int recid
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Convert a recoverable signature into a normal signature.
*
* Returns: 1
* Out: sig: a pointer to a normal signature (cannot be NULL).
* In: sigin: a pointer to a recoverable signature (cannot be NULL).
*/
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_convert(
const secp256k1_context* ctx,
secp256k1_ecdsa_signature* sig,
const secp256k1_ecdsa_recoverable_signature* sigin
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Serialize an ECDSA signature in compact format (64 bytes + recovery id).
*
* Returns: 1
* Args: ctx: a secp256k1 context object
* Out: output64: a pointer to a 64-byte array of the compact signature (cannot be NULL)
* recid: a pointer to an integer to hold the recovery id (can be NULL).
* In: sig: a pointer to an initialized signature object (cannot be NULL)
*/
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_serialize_compact(
const secp256k1_context* ctx,
unsigned char *output64,
int *recid,
const secp256k1_ecdsa_recoverable_signature* sig
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
/** Create a recoverable ECDSA signature.
*
* Returns: 1: signature created
* 0: the nonce generation function failed, or the private key was invalid.
* Args: ctx: pointer to a context object, initialized for signing (cannot be NULL)
* Out: sig: pointer to an array where the signature will be placed (cannot be NULL)
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
*/
SECP256K1_API int secp256k1_ecdsa_sign_recoverable(
const secp256k1_context* ctx,
secp256k1_ecdsa_recoverable_signature *sig,
const unsigned char *msg32,
const unsigned char *seckey,
secp256k1_nonce_function noncefp,
const void *ndata
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Recover an ECDSA public key from a signature.
*
* Returns: 1: public key successfully recovered (which guarantees a correct signature).
* 0: otherwise.
* Args: ctx: pointer to a context object, initialized for verification (cannot be NULL)
* Out: pubkey: pointer to the recoved public key (cannot be NULL)
* In: sig: pointer to initialized signature that supports pubkey recovery (cannot be NULL)
* msg32: the 32-byte message hash assumed to be signed (cannot be NULL)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_recover(
const secp256k1_context* ctx,
secp256k1_pubkey *pubkey,
const secp256k1_ecdsa_recoverable_signature *sig,
const unsigned char *msg32
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
# ifdef __cplusplus
}
# endif
#endif

@ -0,0 +1,173 @@
#ifndef _SECP256K1_SCHNORR_
# define _SECP256K1_SCHNORR_
# include "secp256k1.h"
# ifdef __cplusplus
extern "C" {
# endif
/** Create a signature using a custom EC-Schnorr-SHA256 construction. It
* produces non-malleable 64-byte signatures which support public key recovery
* batch validation, and multiparty signing.
* Returns: 1: signature created
* 0: the nonce generation function failed, or the private key was
* invalid.
* Args: ctx: pointer to a context object, initialized for signing
* (cannot be NULL)
* Out: sig64: pointer to a 64-byte array where the signature will be
* placed (cannot be NULL)
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL,
* secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation
* function (can be NULL)
*/
SECP256K1_API int secp256k1_schnorr_sign(
const secp256k1_context* ctx,
unsigned char *sig64,
const unsigned char *msg32,
const unsigned char *seckey,
secp256k1_nonce_function noncefp,
const void *ndata
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Verify a signature created by secp256k1_schnorr_sign.
* Returns: 1: correct signature
* 0: incorrect signature
* Args: ctx: a secp256k1 context object, initialized for verification.
* In: sig64: the 64-byte signature being verified (cannot be NULL)
* msg32: the 32-byte message hash being verified (cannot be NULL)
* pubkey: the public key to verify with (cannot be NULL)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_schnorr_verify(
const secp256k1_context* ctx,
const unsigned char *sig64,
const unsigned char *msg32,
const secp256k1_pubkey *pubkey
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Recover an EC public key from a Schnorr signature created using
* secp256k1_schnorr_sign.
* Returns: 1: public key successfully recovered (which guarantees a correct
* signature).
* 0: otherwise.
* Args: ctx: pointer to a context object, initialized for
* verification (cannot be NULL)
* Out: pubkey: pointer to a pubkey to set to the recovered public key
* (cannot be NULL).
* In: sig64: signature as 64 byte array (cannot be NULL)
* msg32: the 32-byte message hash assumed to be signed (cannot
* be NULL)
*/
SECP256K1_API int secp256k1_schnorr_recover(
const secp256k1_context* ctx,
secp256k1_pubkey *pubkey,
const unsigned char *sig64,
const unsigned char *msg32
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Generate a nonce pair deterministically for use with
* secp256k1_schnorr_partial_sign.
* Returns: 1: valid nonce pair was generated.
* 0: otherwise (nonce generation function failed)
* Args: ctx: pointer to a context object, initialized for signing
* (cannot be NULL)
* Out: pubnonce: public side of the nonce (cannot be NULL)
* privnonce32: private side of the nonce (32 byte) (cannot be NULL)
* In: msg32: the 32-byte message hash assumed to be signed (cannot
* be NULL)
* sec32: the 32-byte private key (cannot be NULL)
* noncefp: pointer to a nonce generation function. If NULL,
* secp256k1_nonce_function_default is used
* noncedata: pointer to arbitrary data used by the nonce generation
* function (can be NULL)
*
* Do not use the output as a private/public key pair for signing/validation.
*/
SECP256K1_API int secp256k1_schnorr_generate_nonce_pair(
const secp256k1_context* ctx,
secp256k1_pubkey *pubnonce,
unsigned char *privnonce32,
const unsigned char *msg32,
const unsigned char *sec32,
secp256k1_nonce_function noncefp,
const void* noncedata
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Produce a partial Schnorr signature, which can be combined using
* secp256k1_schnorr_partial_combine, to end up with a full signature that is
* verifiable using secp256k1_schnorr_verify.
* Returns: 1: signature created succesfully.
* 0: no valid signature exists with this combination of keys, nonces
* and message (chance around 1 in 2^128)
* -1: invalid private key, nonce, or public nonces.
* Args: ctx: pointer to context object, initialized for signing (cannot
* be NULL)
* Out: sig64: pointer to 64-byte array to put partial signature in
* In: msg32: pointer to 32-byte message to sign
* sec32: pointer to 32-byte private key
* pubnonce_others: pointer to pubkey containing the sum of the other's
* nonces (see secp256k1_ec_pubkey_combine)
* secnonce32: pointer to 32-byte array containing our nonce
*
* The intended procedure for creating a multiparty signature is:
* - Each signer S[i] with private key x[i] and public key Q[i] runs
* secp256k1_schnorr_generate_nonce_pair to produce a pair (k[i],R[i]) of
* private/public nonces.
* - All signers communicate their public nonces to each other (revealing your
* private nonce can lead to discovery of your private key, so it should be
* considered secret).
* - All signers combine all the public nonces they received (excluding their
* own) using secp256k1_ec_pubkey_combine to obtain an
* Rall[i] = sum(R[0..i-1,i+1..n]).
* - All signers produce a partial signature using
* secp256k1_schnorr_partial_sign, passing in their own private key x[i],
* their own private nonce k[i], and the sum of the others' public nonces
* Rall[i].
* - All signers communicate their partial signatures to each other.
* - Someone combines all partial signatures using
* secp256k1_schnorr_partial_combine, to obtain a full signature.
* - The resulting signature is validatable using secp256k1_schnorr_verify, with
* public key equal to the result of secp256k1_ec_pubkey_combine of the
* signers' public keys (sum(Q[0..n])).
*
* Note that secp256k1_schnorr_partial_combine and secp256k1_ec_pubkey_combine
* function take their arguments in any order, and it is possible to
* pre-combine several inputs already with one call, and add more inputs later
* by calling the function again (they are commutative and associative).
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_schnorr_partial_sign(
const secp256k1_context* ctx,
unsigned char *sig64,
const unsigned char *msg32,
const unsigned char *sec32,
const secp256k1_pubkey *pubnonce_others,
const unsigned char *secnonce32
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5) SECP256K1_ARG_NONNULL(6);
/** Combine multiple Schnorr partial signatures.
* Returns: 1: the passed signatures were succesfully combined.
* 0: the resulting signature is not valid (chance of 1 in 2^256)
* -1: some inputs were invalid, or the signatures were not created
* using the same set of nonces
* Args: ctx: pointer to a context object
* Out: sig64: pointer to a 64-byte array to place the combined signature
* (cannot be NULL)
* In: sig64sin: pointer to an array of n pointers to 64-byte input
* signatures
* n: the number of signatures to combine (at least 1)
*/
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_schnorr_partial_combine(
const secp256k1_context* ctx,
unsigned char *sig64,
const unsigned char * const * sig64sin,
int n
) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
# ifdef __cplusplus
}
# endif
#endif

@ -0,0 +1,32 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_BASIC_CONFIG_
#define _SECP256K1_BASIC_CONFIG_
#ifdef USE_BASIC_CONFIG
#undef USE_ASM_X86_64
#undef USE_ENDOMORPHISM
#undef USE_FIELD_10X26
#undef USE_FIELD_5X52
#undef USE_FIELD_INV_BUILTIN
#undef USE_FIELD_INV_NUM
#undef USE_NUM_GMP
#undef USE_NUM_NONE
#undef USE_SCALAR_4X64
#undef USE_SCALAR_8X32
#undef USE_SCALAR_INV_BUILTIN
#undef USE_SCALAR_INV_NUM
#define USE_NUM_NONE 1
#define USE_FIELD_INV_BUILTIN 1
#define USE_SCALAR_INV_BUILTIN 1
#define USE_FIELD_10X26 1
#define USE_SCALAR_8X32 1
#endif // USE_BASIC_CONFIG
#endif // _SECP256K1_BASIC_CONFIG_

@ -20,7 +20,9 @@ static double gettimedouble(void) {
void print_number(double x) {
double y = x;
int c = 0;
if (y < 0.0) y = -y;
if (y < 0.0) {
y = -y;
}
while (y < 100.0) {
y *= 10.0;
c++;
@ -35,20 +37,28 @@ void run_benchmark(char *name, void (*benchmark)(void*), void (*setup)(void*), v
double max = 0.0;
for (i = 0; i < count; i++) {
double begin, total;
if (setup) setup(data);
if (setup != NULL) {
setup(data);
}
begin = gettimedouble();
benchmark(data);
total = gettimedouble() - begin;
if (teardown) teardown(data);
if (total < min) min = total;
if (total > max) max = total;
if (teardown != NULL) {
teardown(data);
}
if (total < min) {
min = total;
}
if (total > max) {
max = total;
}
sum += total;
}
printf("%s: min ", name);
print_number(min * 1000000.0 / iter);
printf("us / avg ");
print_number((sum / count) * 1000000.0 / iter);
printf("us / avg ");
printf("us / max ");
print_number(max * 1000000.0 / iter);
printf("us\n");
}

@ -0,0 +1,53 @@
/**********************************************************************
* Copyright (c) 2015 Pieter Wuille, Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#include <string.h>
#include "include/secp256k1.h"
#include "include/secp256k1_ecdh.h"
#include "util.h"
#include "bench.h"
typedef struct {
secp256k1_context *ctx;
secp256k1_pubkey point;
unsigned char scalar[32];
} bench_ecdh_t;
static void bench_ecdh_setup(void* arg) {
int i;
bench_ecdh_t *data = (bench_ecdh_t*)arg;
const unsigned char point[] = {
0x03,
0x54, 0x94, 0xc1, 0x5d, 0x32, 0x09, 0x97, 0x06,
0xc2, 0x39, 0x5f, 0x94, 0x34, 0x87, 0x45, 0xfd,
0x75, 0x7c, 0xe3, 0x0e, 0x4e, 0x8c, 0x90, 0xfb,
0xa2, 0xba, 0xd1, 0x84, 0xf8, 0x83, 0xc6, 0x9f
};
data->ctx = secp256k1_context_create(0);
for (i = 0; i < 32; i++) {
data->scalar[i] = i + 1;
}
CHECK(secp256k1_ec_pubkey_parse(data->ctx, &data->point, point, sizeof(point)) == 1);
}
static void bench_ecdh(void* arg) {
int i;
unsigned char res[32];
bench_ecdh_t *data = (bench_ecdh_t*)arg;
for (i = 0; i < 20000; i++) {
CHECK(secp256k1_ecdh(data->ctx, res, &data->point, data->scalar) == 1);
}
}
int main(void) {
bench_ecdh_t data;
run_benchmark("ecdh", bench_ecdh, bench_ecdh_setup, NULL, &data, 10, 20000);
return 0;
}

@ -13,15 +13,17 @@
#include "field_impl.h"
#include "group_impl.h"
#include "scalar_impl.h"
#include "ecmult_const_impl.h"
#include "ecmult_impl.h"
#include "bench.h"
#include "secp256k1.c"
typedef struct {
secp256k1_scalar_t scalar_x, scalar_y;
secp256k1_fe_t fe_x, fe_y;
secp256k1_ge_t ge_x, ge_y;
secp256k1_gej_t gej_x, gej_y;
unsigned char data[32];
secp256k1_scalar scalar_x, scalar_y;
secp256k1_fe fe_x, fe_y;
secp256k1_ge ge_x, ge_y;
secp256k1_gej gej_x, gej_y;
unsigned char data[64];
int wnaf[256];
} bench_inv_t;
@ -51,6 +53,7 @@ void bench_setup(void* arg) {
secp256k1_gej_set_ge(&data->gej_x, &data->ge_x);
secp256k1_gej_set_ge(&data->gej_y, &data->ge_y);
memcpy(data->data, init_x, 32);
memcpy(data->data + 32, init_y, 32);
}
void bench_scalar_add(void* arg) {
@ -95,8 +98,8 @@ void bench_scalar_split(void* arg) {
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 20000; i++) {
secp256k1_scalar_t l, r;
secp256k1_scalar_split_lambda_var(&l, &r, &data->scalar_x);
secp256k1_scalar l, r;
secp256k1_scalar_split_lambda(&l, &r, &data->scalar_x);
secp256k1_scalar_add(&data->scalar_x, &data->scalar_x, &data->scalar_y);
}
}
@ -193,7 +196,7 @@ void bench_group_double_var(void* arg) {
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 200000; i++) {
secp256k1_gej_double_var(&data->gej_x, &data->gej_x);
secp256k1_gej_double_var(&data->gej_x, &data->gej_x, NULL);
}
}
@ -202,7 +205,7 @@ void bench_group_add_var(void* arg) {
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 200000; i++) {
secp256k1_gej_add_var(&data->gej_x, &data->gej_x, &data->gej_y);
secp256k1_gej_add_var(&data->gej_x, &data->gej_x, &data->gej_y, NULL);
}
}
@ -220,7 +223,7 @@ void bench_group_add_affine_var(void* arg) {
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 200000; i++) {
secp256k1_gej_add_ge_var(&data->gej_x, &data->gej_x, &data->ge_y);
secp256k1_gej_add_ge_var(&data->gej_x, &data->gej_x, &data->ge_y, NULL);
}
}
@ -229,7 +232,17 @@ void bench_ecmult_wnaf(void* arg) {
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 20000; i++) {
secp256k1_ecmult_wnaf(data->wnaf, &data->scalar_x, WINDOW_A);
secp256k1_ecmult_wnaf(data->wnaf, 256, &data->scalar_x, WINDOW_A);
secp256k1_scalar_add(&data->scalar_x, &data->scalar_x, &data->scalar_y);
}
}
void bench_wnaf_const(void* arg) {
int i;
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 20000; i++) {
secp256k1_wnaf_const(data->wnaf, data->scalar_x, WINDOW_A);
secp256k1_scalar_add(&data->scalar_x, &data->scalar_x, &data->scalar_y);
}
}
@ -265,11 +278,27 @@ void bench_rfc6979_hmac_sha256(void* arg) {
secp256k1_rfc6979_hmac_sha256_t rng;
for (i = 0; i < 20000; i++) {
secp256k1_rfc6979_hmac_sha256_initialize(&rng, data->data, 32, data->data, 32, NULL, 0);
secp256k1_rfc6979_hmac_sha256_initialize(&rng, data->data, 64);
secp256k1_rfc6979_hmac_sha256_generate(&rng, data->data, 32);
}
}
void bench_context_verify(void* arg) {
int i;
(void)arg;
for (i = 0; i < 20; i++) {
secp256k1_context_destroy(secp256k1_context_create(SECP256K1_CONTEXT_VERIFY));
}
}
void bench_context_sign(void* arg) {
int i;
(void)arg;
for (i = 0; i < 200; i++) {
secp256k1_context_destroy(secp256k1_context_create(SECP256K1_CONTEXT_SIGN));
}
}
int have_flag(int argc, char** argv, char *flag) {
char** argm = argv + argc;
@ -278,7 +307,9 @@ int have_flag(int argc, char** argv, char *flag) {
return 1;
}
while (argv != NULL && argv != argm) {
if (strcmp(*argv, flag) == 0) return 1;
if (strcmp(*argv, flag) == 0) {
return 1;
}
argv++;
}
return 0;
@ -309,10 +340,15 @@ int main(int argc, char **argv) {
if (have_flag(argc, argv, "group") || have_flag(argc, argv, "add")) run_benchmark("group_add_affine", bench_group_add_affine, bench_setup, NULL, &data, 10, 200000);
if (have_flag(argc, argv, "group") || have_flag(argc, argv, "add")) run_benchmark("group_add_affine_var", bench_group_add_affine_var, bench_setup, NULL, &data, 10, 200000);
if (have_flag(argc, argv, "ecmult") || have_flag(argc, argv, "wnaf")) run_benchmark("wnaf_const", bench_wnaf_const, bench_setup, NULL, &data, 10, 20000);
if (have_flag(argc, argv, "ecmult") || have_flag(argc, argv, "wnaf")) run_benchmark("ecmult_wnaf", bench_ecmult_wnaf, bench_setup, NULL, &data, 10, 20000);
if (have_flag(argc, argv, "hash") || have_flag(argc, argv, "sha256")) run_benchmark("hash_sha256", bench_sha256, bench_setup, NULL, &data, 10, 20000);
if (have_flag(argc, argv, "hash") || have_flag(argc, argv, "hmac")) run_benchmark("hash_hmac_sha256", bench_hmac_sha256, bench_setup, NULL, &data, 10, 20000);
if (have_flag(argc, argv, "hash") || have_flag(argc, argv, "rng6979")) run_benchmark("hash_rfc6979_hmac_sha256", bench_rfc6979_hmac_sha256, bench_setup, NULL, &data, 10, 20000);
if (have_flag(argc, argv, "context") || have_flag(argc, argv, "verify")) run_benchmark("context_verify", bench_context_verify, bench_setup, NULL, &data, 10, 20);
if (have_flag(argc, argv, "context") || have_flag(argc, argv, "sign")) run_benchmark("context_sign", bench_context_sign, bench_setup, NULL, &data, 10, 200);
return 0;
}

@ -1,14 +1,16 @@
/**********************************************************************
* Copyright (c) 2014 Pieter Wuille *
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#include "include/secp256k1.h"
#include "include/secp256k1_recovery.h"
#include "util.h"
#include "bench.h"
typedef struct {
secp256k1_context *ctx;
unsigned char msg[32];
unsigned char sig[64];
} bench_recover_t;
@ -16,16 +18,20 @@ typedef struct {
void bench_recover(void* arg) {
int i;
bench_recover_t *data = (bench_recover_t*)arg;
unsigned char pubkey[33];
secp256k1_pubkey pubkey;
unsigned char pubkeyc[33];
for (i = 0; i < 20000; i++) {
int j;
int pubkeylen = 33;
CHECK(secp256k1_ecdsa_recover_compact(data->msg, data->sig, pubkey, &pubkeylen, 1, i % 2));
size_t pubkeylen = 33;
secp256k1_ecdsa_recoverable_signature sig;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(data->ctx, &sig, data->sig, i % 2));
CHECK(secp256k1_ecdsa_recover(data->ctx, &pubkey, &sig, data->msg));
CHECK(secp256k1_ec_pubkey_serialize(data->ctx, pubkeyc, &pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED));
for (j = 0; j < 32; j++) {
data->sig[j + 32] = data->msg[j]; /* Move former message to S. */
data->msg[j] = data->sig[j]; /* Move former R to message. */
data->sig[j] = pubkey[j + 1]; /* Move recovered pubkey X coordinate to R (which must be a valid X coordinate). */
data->sig[j] = pubkeyc[j + 1]; /* Move recovered pubkey X coordinate to R (which must be a valid X coordinate). */
}
}
}
@ -34,16 +40,21 @@ void bench_recover_setup(void* arg) {
int i;
bench_recover_t *data = (bench_recover_t*)arg;
for (i = 0; i < 32; i++) data->msg[i] = 1 + i;
for (i = 0; i < 64; i++) data->sig[i] = 65 + i;
for (i = 0; i < 32; i++) {
data->msg[i] = 1 + i;
}
for (i = 0; i < 64; i++) {
data->sig[i] = 65 + i;
}
}
int main(void) {
bench_recover_t data;
secp256k1_start(SECP256K1_START_VERIFY);
data.ctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY);
run_benchmark("ecdsa_recover", bench_recover, bench_recover_setup, NULL, &data, 10, 20000);
secp256k1_stop();
secp256k1_context_destroy(data.ctx);
return 0;
}

@ -0,0 +1,73 @@
/**********************************************************************
* Copyright (c) 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#include <stdio.h>
#include <string.h>
#include "include/secp256k1.h"
#include "include/secp256k1_schnorr.h"
#include "util.h"
#include "bench.h"
typedef struct {
unsigned char key[32];
unsigned char sig[64];
unsigned char pubkey[33];
size_t pubkeylen;
} benchmark_schnorr_sig_t;
typedef struct {
secp256k1_context *ctx;
unsigned char msg[32];
benchmark_schnorr_sig_t sigs[64];
int numsigs;
} benchmark_schnorr_verify_t;
static void benchmark_schnorr_init(void* arg) {
int i, k;
benchmark_schnorr_verify_t* data = (benchmark_schnorr_verify_t*)arg;
for (i = 0; i < 32; i++) {
data->msg[i] = 1 + i;
}
for (k = 0; k < data->numsigs; k++) {
secp256k1_pubkey pubkey;
for (i = 0; i < 32; i++) {
data->sigs[k].key[i] = 33 + i + k;
}
secp256k1_schnorr_sign(data->ctx, data->sigs[k].sig, data->msg, data->sigs[k].key, NULL, NULL);
data->sigs[k].pubkeylen = 33;
CHECK(secp256k1_ec_pubkey_create(data->ctx, &pubkey, data->sigs[k].key));
CHECK(secp256k1_ec_pubkey_serialize(data->ctx, data->sigs[k].pubkey, &data->sigs[k].pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED));
}
}
static void benchmark_schnorr_verify(void* arg) {
int i;
benchmark_schnorr_verify_t* data = (benchmark_schnorr_verify_t*)arg;
for (i = 0; i < 20000 / data->numsigs; i++) {
secp256k1_pubkey pubkey;
data->sigs[0].sig[(i >> 8) % 64] ^= (i & 0xFF);
CHECK(secp256k1_ec_pubkey_parse(data->ctx, &pubkey, data->sigs[0].pubkey, data->sigs[0].pubkeylen));
CHECK(secp256k1_schnorr_verify(data->ctx, data->sigs[0].sig, data->msg, &pubkey) == ((i & 0xFF) == 0));
data->sigs[0].sig[(i >> 8) % 64] ^= (i & 0xFF);
}
}
int main(void) {
benchmark_schnorr_verify_t data;
data.ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN | SECP256K1_CONTEXT_VERIFY);
data.numsigs = 1;
run_benchmark("schnorr_verify", benchmark_schnorr_verify, benchmark_schnorr_init, NULL, &data, 10, 20000);
secp256k1_context_destroy(data.ctx);
return 0;
}

@ -9,6 +9,7 @@
#include "bench.h"
typedef struct {
secp256k1_context* ctx;
unsigned char msg[32];
unsigned char key[32];
} bench_sign_t;
@ -17,32 +18,39 @@ static void bench_sign_setup(void* arg) {
int i;
bench_sign_t *data = (bench_sign_t*)arg;
for (i = 0; i < 32; i++) data->msg[i] = i + 1;
for (i = 0; i < 32; i++) data->key[i] = i + 65;
for (i = 0; i < 32; i++) {
data->msg[i] = i + 1;
}
for (i = 0; i < 32; i++) {
data->key[i] = i + 65;
}
}
static void bench_sign(void* arg) {
int i;
bench_sign_t *data = (bench_sign_t*)arg;
unsigned char sig[64];
unsigned char sig[74];
for (i = 0; i < 20000; i++) {
size_t siglen = 74;
int j;
int recid = 0;
CHECK(secp256k1_ecdsa_sign_compact(data->msg, sig, data->key, NULL, NULL, &recid));
secp256k1_ecdsa_signature signature;
CHECK(secp256k1_ecdsa_sign(data->ctx, &signature, data->msg, data->key, NULL, NULL));
CHECK(secp256k1_ecdsa_signature_serialize_der(data->ctx, sig, &siglen, &signature));
for (j = 0; j < 32; j++) {
data->msg[j] = sig[j]; /* Move former R to message. */
data->key[j] = sig[j + 32]; /* Move former S to key. */
data->msg[j] = sig[j];
data->key[j] = sig[j + 32];
}
}
}
int main(void) {
bench_sign_t data;
secp256k1_start(SECP256K1_START_SIGN);
data.ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
run_benchmark("ecdsa_sign", bench_sign, bench_sign_setup, NULL, &data, 10, 20000);
secp256k1_stop();
secp256k1_context_destroy(data.ctx);
return 0;
}

@ -12,12 +12,13 @@
#include "bench.h"
typedef struct {
secp256k1_context *ctx;
unsigned char msg[32];
unsigned char key[32];
unsigned char sig[72];
int siglen;
size_t siglen;
unsigned char pubkey[33];
int pubkeylen;
size_t pubkeylen;
} benchmark_verify_t;
static void benchmark_verify(void* arg) {
@ -25,10 +26,14 @@ static void benchmark_verify(void* arg) {
benchmark_verify_t* data = (benchmark_verify_t*)arg;
for (i = 0; i < 20000; i++) {
secp256k1_pubkey pubkey;
secp256k1_ecdsa_signature sig;
data->sig[data->siglen - 1] ^= (i & 0xFF);
data->sig[data->siglen - 2] ^= ((i >> 8) & 0xFF);
data->sig[data->siglen - 3] ^= ((i >> 16) & 0xFF);
CHECK(secp256k1_ecdsa_verify(data->msg, data->sig, data->siglen, data->pubkey, data->pubkeylen) == (i == 0));
CHECK(secp256k1_ec_pubkey_parse(data->ctx, &pubkey, data->pubkey, data->pubkeylen) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(data->ctx, &sig, data->sig, data->siglen) == 1);
CHECK(secp256k1_ecdsa_verify(data->ctx, &sig, data->msg, &pubkey) == (i == 0));
data->sig[data->siglen - 1] ^= (i & 0xFF);
data->sig[data->siglen - 2] ^= ((i >> 8) & 0xFF);
data->sig[data->siglen - 3] ^= ((i >> 16) & 0xFF);
@ -37,19 +42,26 @@ static void benchmark_verify(void* arg) {
int main(void) {
int i;
secp256k1_pubkey pubkey;
secp256k1_ecdsa_signature sig;
benchmark_verify_t data;
secp256k1_start(SECP256K1_START_VERIFY | SECP256K1_START_SIGN);
data.ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN | SECP256K1_CONTEXT_VERIFY);
for (i = 0; i < 32; i++) data.msg[i] = 1 + i;
for (i = 0; i < 32; i++) data.key[i] = 33 + i;
for (i = 0; i < 32; i++) {
data.msg[i] = 1 + i;
}
for (i = 0; i < 32; i++) {
data.key[i] = 33 + i;
}
data.siglen = 72;
secp256k1_ecdsa_sign(data.msg, data.sig, &data.siglen, data.key, NULL, NULL);
data.pubkeylen = 33;
CHECK(secp256k1_ec_pubkey_create(data.pubkey, &data.pubkeylen, data.key, 1));
CHECK(secp256k1_ecdsa_sign(data.ctx, &sig, data.msg, data.key, NULL, NULL));
CHECK(secp256k1_ecdsa_signature_serialize_der(data.ctx, data.sig, &data.siglen, &sig));
CHECK(secp256k1_ec_pubkey_create(data.ctx, &pubkey, data.key));
CHECK(secp256k1_ec_pubkey_serialize(data.ctx, data.pubkey, &data.pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED) == 1);
run_benchmark("ecdsa_verify", benchmark_verify, NULL, NULL, &data, 10, 20000);
secp256k1_stop();
secp256k1_context_destroy(data.ctx);
return 0;
}

@ -0,0 +1,22 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECDSA_
#define _SECP256K1_ECDSA_
#include <stddef.h>
#include "scalar.h"
#include "group.h"
#include "ecmult.h"
static int secp256k1_ecdsa_sig_parse(secp256k1_scalar *r, secp256k1_scalar *s, const unsigned char *sig, size_t size);
static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, size_t *size, const secp256k1_scalar *r, const secp256k1_scalar *s);
static int secp256k1_ecdsa_sig_verify(const secp256k1_ecmult_context *ctx, const secp256k1_scalar* r, const secp256k1_scalar* s, const secp256k1_ge *pubkey, const secp256k1_scalar *message);
static int secp256k1_ecdsa_sig_sign(const secp256k1_ecmult_gen_context *ctx, secp256k1_scalar* r, secp256k1_scalar* s, const secp256k1_scalar *seckey, const secp256k1_scalar *message, const secp256k1_scalar *nonce, int *recid);
static int secp256k1_ecdsa_sig_recover(const secp256k1_ecmult_context *ctx, const secp256k1_scalar* r, const secp256k1_scalar* s, secp256k1_ge *pubkey, const secp256k1_scalar *message, int recid);
#endif

@ -28,7 +28,7 @@
* sage: '%x' % (EllipticCurve ([F (a), F (b)]).order())
* 'fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141'
*/
static const secp256k1_fe_t secp256k1_ecdsa_const_order_as_fe = SECP256K1_FE_CONST(
static const secp256k1_fe secp256k1_ecdsa_const_order_as_fe = SECP256K1_FE_CONST(
0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFEUL,
0xBAAEDCE6UL, 0xAF48A03BUL, 0xBFD25E8CUL, 0xD0364141UL
);
@ -42,16 +42,16 @@ static const secp256k1_fe_t secp256k1_ecdsa_const_order_as_fe = SECP256K1_FE_CON
* sage: '%x' % (p - EllipticCurve ([F (a), F (b)]).order())
* '14551231950b75fc4402da1722fc9baee'
*/
static const secp256k1_fe_t secp256k1_ecdsa_const_p_minus_order = SECP256K1_FE_CONST(
static const secp256k1_fe secp256k1_ecdsa_const_p_minus_order = SECP256K1_FE_CONST(
0, 0, 0, 1, 0x45512319UL, 0x50B75FC4UL, 0x402DA172UL, 0x2FC9BAEEUL
);
static int secp256k1_ecdsa_sig_parse(secp256k1_ecdsa_sig_t *r, const unsigned char *sig, int size) {
static int secp256k1_ecdsa_sig_parse(secp256k1_scalar *rr, secp256k1_scalar *rs, const unsigned char *sig, size_t size) {
unsigned char ra[32] = {0}, sa[32] = {0};
const unsigned char *rp;
const unsigned char *sp;
int lenr;
int lens;
size_t lenr;
size_t lens;
int overflow;
if (sig[0] != 0x30) {
return 0;
@ -98,26 +98,27 @@ static int secp256k1_ecdsa_sig_parse(secp256k1_ecdsa_sig_t *r, const unsigned ch
memcpy(ra + 32 - lenr, rp, lenr);
memcpy(sa + 32 - lens, sp, lens);
overflow = 0;
secp256k1_scalar_set_b32(&r->r, ra, &overflow);
secp256k1_scalar_set_b32(rr, ra, &overflow);
if (overflow) {
return 0;
}
secp256k1_scalar_set_b32(&r->s, sa, &overflow);
secp256k1_scalar_set_b32(rs, sa, &overflow);
if (overflow) {
return 0;
}
return 1;
}
static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, int *size, const secp256k1_ecdsa_sig_t *a) {
static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, size_t *size, const secp256k1_scalar* ar, const secp256k1_scalar* as) {
unsigned char r[33] = {0}, s[33] = {0};
unsigned char *rp = r, *sp = s;
int lenR = 33, lenS = 33;
secp256k1_scalar_get_b32(&r[1], &a->r);
secp256k1_scalar_get_b32(&s[1], &a->s);
size_t lenR = 33, lenS = 33;
secp256k1_scalar_get_b32(&r[1], ar);
secp256k1_scalar_get_b32(&s[1], as);
while (lenR > 1 && rp[0] == 0 && rp[1] < 0x80) { lenR--; rp++; }
while (lenS > 1 && sp[0] == 0 && sp[1] < 0x80) { lenS--; sp++; }
if (*size < 6+lenS+lenR) {
*size = 6 + lenS + lenR;
return 0;
}
*size = 6 + lenS + lenR;
@ -132,26 +133,26 @@ static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, int *size, const se
return 1;
}
static int secp256k1_ecdsa_sig_verify(const secp256k1_ecdsa_sig_t *sig, const secp256k1_ge_t *pubkey, const secp256k1_scalar_t *message) {
static int secp256k1_ecdsa_sig_verify(const secp256k1_ecmult_context *ctx, const secp256k1_scalar *sigr, const secp256k1_scalar *sigs, const secp256k1_ge *pubkey, const secp256k1_scalar *message) {
unsigned char c[32];
secp256k1_scalar_t sn, u1, u2;
secp256k1_fe_t xr;
secp256k1_gej_t pubkeyj;
secp256k1_gej_t pr;
secp256k1_scalar sn, u1, u2;
secp256k1_fe xr;
secp256k1_gej pubkeyj;
secp256k1_gej pr;
if (secp256k1_scalar_is_zero(&sig->r) || secp256k1_scalar_is_zero(&sig->s)) {
if (secp256k1_scalar_is_zero(sigr) || secp256k1_scalar_is_zero(sigs)) {
return 0;
}
secp256k1_scalar_inverse_var(&sn, &sig->s);
secp256k1_scalar_inverse_var(&sn, sigs);
secp256k1_scalar_mul(&u1, &sn, message);
secp256k1_scalar_mul(&u2, &sn, &sig->r);
secp256k1_scalar_mul(&u2, &sn, sigr);
secp256k1_gej_set_ge(&pubkeyj, pubkey);
secp256k1_ecmult(&pr, &pubkeyj, &u2, &u1);
secp256k1_ecmult(ctx, &pr, &pubkeyj, &u2, &u1);
if (secp256k1_gej_is_infinity(&pr)) {
return 0;
}
secp256k1_scalar_get_b32(c, &sig->r);
secp256k1_scalar_get_b32(c, sigr);
secp256k1_fe_set_b32(&xr, c);
/** We now have the recomputed R point in pr, and its claimed x coordinate (modulo n)
@ -186,19 +187,19 @@ static int secp256k1_ecdsa_sig_verify(const secp256k1_ecdsa_sig_t *sig, const se
return 0;
}
static int secp256k1_ecdsa_sig_recover(const secp256k1_ecdsa_sig_t *sig, secp256k1_ge_t *pubkey, const secp256k1_scalar_t *message, int recid) {
static int secp256k1_ecdsa_sig_recover(const secp256k1_ecmult_context *ctx, const secp256k1_scalar *sigr, const secp256k1_scalar* sigs, secp256k1_ge *pubkey, const secp256k1_scalar *message, int recid) {
unsigned char brx[32];
secp256k1_fe_t fx;
secp256k1_ge_t x;
secp256k1_gej_t xj;
secp256k1_scalar_t rn, u1, u2;
secp256k1_gej_t qj;
secp256k1_fe fx;
secp256k1_ge x;
secp256k1_gej xj;
secp256k1_scalar rn, u1, u2;
secp256k1_gej qj;
if (secp256k1_scalar_is_zero(&sig->r) || secp256k1_scalar_is_zero(&sig->s)) {
if (secp256k1_scalar_is_zero(sigr) || secp256k1_scalar_is_zero(sigs)) {
return 0;
}
secp256k1_scalar_get_b32(brx, &sig->r);
secp256k1_scalar_get_b32(brx, sigr);
VERIFY_CHECK(secp256k1_fe_set_b32(&fx, brx)); /* brx comes from a scalar, so is less than the order; certainly less than p */
if (recid & 2) {
if (secp256k1_fe_cmp_var(&fx, &secp256k1_ecdsa_const_p_minus_order) >= 0) {
@ -210,29 +211,29 @@ static int secp256k1_ecdsa_sig_recover(const secp256k1_ecdsa_sig_t *sig, secp256
return 0;
}
secp256k1_gej_set_ge(&xj, &x);
secp256k1_scalar_inverse_var(&rn, &sig->r);
secp256k1_scalar_inverse_var(&rn, sigr);
secp256k1_scalar_mul(&u1, &rn, message);
secp256k1_scalar_negate(&u1, &u1);
secp256k1_scalar_mul(&u2, &rn, &sig->s);
secp256k1_ecmult(&qj, &xj, &u2, &u1);
secp256k1_scalar_mul(&u2, &rn, sigs);
secp256k1_ecmult(ctx, &qj, &xj, &u2, &u1);
secp256k1_ge_set_gej_var(pubkey, &qj);
return !secp256k1_gej_is_infinity(&qj);
}
static int secp256k1_ecdsa_sig_sign(secp256k1_ecdsa_sig_t *sig, const secp256k1_scalar_t *seckey, const secp256k1_scalar_t *message, const secp256k1_scalar_t *nonce, int *recid) {
static int secp256k1_ecdsa_sig_sign(const secp256k1_ecmult_gen_context *ctx, secp256k1_scalar *sigr, secp256k1_scalar *sigs, const secp256k1_scalar *seckey, const secp256k1_scalar *message, const secp256k1_scalar *nonce, int *recid) {
unsigned char b[32];
secp256k1_gej_t rp;
secp256k1_ge_t r;
secp256k1_scalar_t n;
secp256k1_gej rp;
secp256k1_ge r;
secp256k1_scalar n;
int overflow = 0;
secp256k1_ecmult_gen(&rp, nonce);
secp256k1_ecmult_gen(ctx, &rp, nonce);
secp256k1_ge_set_gej(&r, &rp);
secp256k1_fe_normalize(&r.x);
secp256k1_fe_normalize(&r.y);
secp256k1_fe_get_b32(b, &r.x);
secp256k1_scalar_set_b32(&sig->r, b, &overflow);
if (secp256k1_scalar_is_zero(&sig->r)) {
secp256k1_scalar_set_b32(sigr, b, &overflow);
if (secp256k1_scalar_is_zero(sigr)) {
/* P.x = order is on the curve, so technically sig->r could end up zero, which would be an invalid signature. */
secp256k1_gej_clear(&rp);
secp256k1_ge_clear(&r);
@ -241,18 +242,18 @@ static int secp256k1_ecdsa_sig_sign(secp256k1_ecdsa_sig_t *sig, const secp256k1_
if (recid) {
*recid = (overflow ? 2 : 0) | (secp256k1_fe_is_odd(&r.y) ? 1 : 0);
}
secp256k1_scalar_mul(&n, &sig->r, seckey);
secp256k1_scalar_mul(&n, sigr, seckey);
secp256k1_scalar_add(&n, &n, message);
secp256k1_scalar_inverse(&sig->s, nonce);
secp256k1_scalar_mul(&sig->s, &sig->s, &n);
secp256k1_scalar_inverse(sigs, nonce);
secp256k1_scalar_mul(sigs, sigs, &n);
secp256k1_scalar_clear(&n);
secp256k1_gej_clear(&rp);
secp256k1_ge_clear(&r);
if (secp256k1_scalar_is_zero(&sig->s)) {
if (secp256k1_scalar_is_zero(sigs)) {
return 0;
}
if (secp256k1_scalar_is_high(&sig->s)) {
secp256k1_scalar_negate(&sig->s, &sig->s);
if (secp256k1_scalar_is_high(sigs)) {
secp256k1_scalar_negate(sigs, sigs);
if (recid) {
*recid ^= 1;
}

@ -0,0 +1,28 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECKEY_
#define _SECP256K1_ECKEY_
#include <stddef.h>
#include "group.h"
#include "scalar.h"
#include "ecmult.h"
#include "ecmult_gen.h"
static int secp256k1_eckey_pubkey_parse(secp256k1_ge *elem, const unsigned char *pub, size_t size);
static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *pub, size_t *size, unsigned int flags);
static int secp256k1_eckey_privkey_parse(secp256k1_scalar *key, const unsigned char *privkey, size_t privkeylen);
static int secp256k1_eckey_privkey_serialize(const secp256k1_ecmult_gen_context *ctx, unsigned char *privkey, size_t *privkeylen, const secp256k1_scalar *key, unsigned int flags);
static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar *key, const secp256k1_scalar *tweak);
static int secp256k1_eckey_pubkey_tweak_add(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak);
static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar *key, const secp256k1_scalar *tweak);
static int secp256k1_eckey_pubkey_tweak_mul(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak);
#endif

@ -14,12 +14,12 @@
#include "group.h"
#include "ecmult_gen.h"
static int secp256k1_eckey_pubkey_parse(secp256k1_ge_t *elem, const unsigned char *pub, int size) {
static int secp256k1_eckey_pubkey_parse(secp256k1_ge *elem, const unsigned char *pub, size_t size) {
if (size == 33 && (pub[0] == 0x02 || pub[0] == 0x03)) {
secp256k1_fe_t x;
secp256k1_fe x;
return secp256k1_fe_set_b32(&x, pub+1) && secp256k1_ge_set_xo_var(elem, &x, pub[0] == 0x03);
} else if (size == 65 && (pub[0] == 0x04 || pub[0] == 0x06 || pub[0] == 0x07)) {
secp256k1_fe_t x, y;
secp256k1_fe x, y;
if (!secp256k1_fe_set_b32(&x, pub+1) || !secp256k1_fe_set_b32(&y, pub+33)) {
return 0;
}
@ -33,14 +33,14 @@ static int secp256k1_eckey_pubkey_parse(secp256k1_ge_t *elem, const unsigned cha
}
}
static int secp256k1_eckey_pubkey_serialize(secp256k1_ge_t *elem, unsigned char *pub, int *size, int compressed) {
static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *pub, size_t *size, unsigned int flags) {
if (secp256k1_ge_is_infinity(elem)) {
return 0;
}
secp256k1_fe_normalize_var(&elem->x);
secp256k1_fe_normalize_var(&elem->y);
secp256k1_fe_get_b32(&pub[1], &elem->x);
if (compressed) {
if (flags & SECP256K1_EC_COMPRESSED) {
*size = 33;
pub[0] = 0x02 | (secp256k1_fe_is_odd(&elem->y) ? 0x01 : 0x00);
} else {
@ -51,7 +51,7 @@ static int secp256k1_eckey_pubkey_serialize(secp256k1_ge_t *elem, unsigned char
return 1;
}
static int secp256k1_eckey_privkey_parse(secp256k1_scalar_t *key, const unsigned char *privkey, int privkeylen) {
static int secp256k1_eckey_privkey_parse(secp256k1_scalar *key, const unsigned char *privkey, size_t privkeylen) {
unsigned char c[32] = {0};
const unsigned char *end = privkey + privkeylen;
int lenb = 0;
@ -94,13 +94,13 @@ static int secp256k1_eckey_privkey_parse(secp256k1_scalar_t *key, const unsigned
return !overflow;
}
static int secp256k1_eckey_privkey_serialize(unsigned char *privkey, int *privkeylen, const secp256k1_scalar_t *key, int compressed) {
secp256k1_gej_t rp;
secp256k1_ge_t r;
int pubkeylen = 0;
secp256k1_ecmult_gen(&rp, key);
static int secp256k1_eckey_privkey_serialize(const secp256k1_ecmult_gen_context *ctx, unsigned char *privkey, size_t *privkeylen, const secp256k1_scalar *key, unsigned int flags) {
secp256k1_gej rp;
secp256k1_ge r;
size_t pubkeylen = 0;
secp256k1_ecmult_gen(ctx, &rp, key);
secp256k1_ge_set_gej(&r, &rp);
if (compressed) {
if (flags & SECP256K1_EC_COMPRESSED) {
static const unsigned char begin[] = {
0x30,0x81,0xD3,0x02,0x01,0x01,0x04,0x20
};
@ -154,7 +154,7 @@ static int secp256k1_eckey_privkey_serialize(unsigned char *privkey, int *privke
return 1;
}
static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar_t *key, const secp256k1_scalar_t *tweak) {
static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar *key, const secp256k1_scalar *tweak) {
secp256k1_scalar_add(key, key, tweak);
if (secp256k1_scalar_is_zero(key)) {
return 0;
@ -162,12 +162,12 @@ static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar_t *key, const secp
return 1;
}
static int secp256k1_eckey_pubkey_tweak_add(secp256k1_ge_t *key, const secp256k1_scalar_t *tweak) {
secp256k1_gej_t pt;
secp256k1_scalar_t one;
static int secp256k1_eckey_pubkey_tweak_add(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak) {
secp256k1_gej pt;
secp256k1_scalar one;
secp256k1_gej_set_ge(&pt, key);
secp256k1_scalar_set_int(&one, 1);
secp256k1_ecmult(&pt, &pt, &one, tweak);
secp256k1_ecmult(ctx, &pt, &pt, &one, tweak);
if (secp256k1_gej_is_infinity(&pt)) {
return 0;
@ -176,7 +176,7 @@ static int secp256k1_eckey_pubkey_tweak_add(secp256k1_ge_t *key, const secp256k1
return 1;
}
static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar_t *key, const secp256k1_scalar_t *tweak) {
static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar *key, const secp256k1_scalar *tweak) {
if (secp256k1_scalar_is_zero(tweak)) {
return 0;
}
@ -185,16 +185,16 @@ static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar_t *key, const secp
return 1;
}
static int secp256k1_eckey_pubkey_tweak_mul(secp256k1_ge_t *key, const secp256k1_scalar_t *tweak) {
secp256k1_scalar_t zero;
secp256k1_gej_t pt;
static int secp256k1_eckey_pubkey_tweak_mul(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak) {
secp256k1_scalar zero;
secp256k1_gej pt;
if (secp256k1_scalar_is_zero(tweak)) {
return 0;
}
secp256k1_scalar_set_int(&zero, 0);
secp256k1_gej_set_ge(&pt, key);
secp256k1_ecmult(&pt, &pt, tweak, &zero);
secp256k1_ecmult(ctx, &pt, &pt, tweak, &zero);
secp256k1_ge_set_gej(key, &pt);
return 1;
}

@ -0,0 +1,31 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_
#define _SECP256K1_ECMULT_
#include "num.h"
#include "group.h"
typedef struct {
/* For accelerating the computation of a*P + b*G: */
secp256k1_ge_storage (*pre_g)[]; /* odd multiples of the generator */
#ifdef USE_ENDOMORPHISM
secp256k1_ge_storage (*pre_g_128)[]; /* odd multiples of 2^128*generator */
#endif
} secp256k1_ecmult_context;
static void secp256k1_ecmult_context_init(secp256k1_ecmult_context *ctx);
static void secp256k1_ecmult_context_build(secp256k1_ecmult_context *ctx, const secp256k1_callback *cb);
static void secp256k1_ecmult_context_clone(secp256k1_ecmult_context *dst,
const secp256k1_ecmult_context *src, const secp256k1_callback *cb);
static void secp256k1_ecmult_context_clear(secp256k1_ecmult_context *ctx);
static int secp256k1_ecmult_context_is_built(const secp256k1_ecmult_context *ctx);
/** Double multiply: R = na*A + ng*G */
static void secp256k1_ecmult(const secp256k1_ecmult_context *ctx, secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_scalar *na, const secp256k1_scalar *ng);
#endif

@ -1,19 +1,15 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Copyright (c) 2015 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_GEN_
#define _SECP256K1_ECMULT_GEN_
#ifndef _SECP256K1_ECMULT_CONST_
#define _SECP256K1_ECMULT_CONST_
#include "scalar.h"
#include "group.h"
static void secp256k1_ecmult_gen_start(void);
static void secp256k1_ecmult_gen_stop(void);
/** Multiply with the generator: R = a*G */
static void secp256k1_ecmult_gen(secp256k1_gej_t *r, const secp256k1_scalar_t *a);
static void secp256k1_ecmult_const(secp256k1_gej *r, const secp256k1_ge *a, const secp256k1_scalar *q);
#endif

@ -0,0 +1,260 @@
/**********************************************************************
* Copyright (c) 2015 Pieter Wuille, Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_CONST_IMPL_
#define _SECP256K1_ECMULT_CONST_IMPL_
#include "scalar.h"
#include "group.h"
#include "ecmult_const.h"
#include "ecmult_impl.h"
#ifdef USE_ENDOMORPHISM
#define WNAF_BITS 128
#else
#define WNAF_BITS 256
#endif
#define WNAF_SIZE(w) ((WNAF_BITS + (w) - 1) / (w))
/* This is like `ECMULT_TABLE_GET_GE` but is constant time */
#define ECMULT_CONST_TABLE_GET_GE(r,pre,n,w) do { \
int m; \
int abs_n = (n) * (((n) > 0) * 2 - 1); \
int idx_n = abs_n / 2; \
secp256k1_fe neg_y; \
VERIFY_CHECK(((n) & 1) == 1); \
VERIFY_CHECK((n) >= -((1 << ((w)-1)) - 1)); \
VERIFY_CHECK((n) <= ((1 << ((w)-1)) - 1)); \
VERIFY_SETUP(secp256k1_fe_clear(&(r)->x)); \
VERIFY_SETUP(secp256k1_fe_clear(&(r)->y)); \
for (m = 0; m < ECMULT_TABLE_SIZE(w); m++) { \
/* This loop is used to avoid secret data in array indices. See
* the comment in ecmult_gen_impl.h for rationale. */ \
secp256k1_fe_cmov(&(r)->x, &(pre)[m].x, m == idx_n); \
secp256k1_fe_cmov(&(r)->y, &(pre)[m].y, m == idx_n); \
} \
(r)->infinity = 0; \
secp256k1_fe_negate(&neg_y, &(r)->y, 1); \
secp256k1_fe_cmov(&(r)->y, &neg_y, (n) != abs_n); \
} while(0)
/** Convert a number to WNAF notation. The number becomes represented by sum(2^{wi} * wnaf[i], i=0..return_val)
* with the following guarantees:
* - each wnaf[i] an odd integer between -(1 << w) and (1 << w)
* - each wnaf[i] is nonzero
* - the number of words set is returned; this is always (WNAF_BITS + w - 1) / w
*
* Adapted from `The Width-w NAF Method Provides Small Memory and Fast Elliptic Scalar
* Multiplications Secure against Side Channel Attacks`, Okeya and Tagaki. M. Joye (Ed.)
* CT-RSA 2003, LNCS 2612, pp. 328-443, 2003. Springer-Verlagy Berlin Heidelberg 2003
*
* Numbers reference steps of `Algorithm SPA-resistant Width-w NAF with Odd Scalar` on pp. 335
*/
static int secp256k1_wnaf_const(int *wnaf, secp256k1_scalar s, int w) {
int global_sign;
int skew = 0;
int word = 0;
/* 1 2 3 */
int u_last;
int u;
#ifdef USE_ENDOMORPHISM
int flip;
int bit;
secp256k1_scalar neg_s;
int not_neg_one;
/* If we are using the endomorphism, we cannot handle even numbers by negating
* them, since we are working with 128-bit numbers whose negations would be 256
* bits, eliminating the performance advantage. Instead we use a technique from
* Section 4.2 of the Okeya/Tagaki paper, which is to add either 1 (for even)
* or 2 (for odd) to the number we are encoding, then compensating after the
* multiplication. */
/* Negative 128-bit numbers will be negated, since otherwise they are 256-bit */
flip = secp256k1_scalar_is_high(&s);
/* We add 1 to even numbers, 2 to odd ones, noting that negation flips parity */
bit = flip ^ (s.d[0] & 1);
/* We check for negative one, since adding 2 to it will cause an overflow */
secp256k1_scalar_negate(&neg_s, &s);
not_neg_one = !secp256k1_scalar_is_one(&neg_s);
secp256k1_scalar_cadd_bit(&s, bit, not_neg_one);
/* If we had negative one, flip == 1, s.d[0] == 0, bit == 1, so caller expects
* that we added two to it and flipped it. In fact for -1 these operations are
* identical. We only flipped, but since skewing is required (in the sense that
* the skew must be 1 or 2, never zero) and flipping is not, we need to change
* our flags to claim that we only skewed. */
global_sign = secp256k1_scalar_cond_negate(&s, flip);
global_sign *= not_neg_one * 2 - 1;
skew = 1 << bit;
#else
/* Otherwise, we just negate to force oddness */
int is_even = secp256k1_scalar_is_even(&s);
global_sign = secp256k1_scalar_cond_negate(&s, is_even);
#endif
/* 4 */
u_last = secp256k1_scalar_shr_int(&s, w);
while (word * w < WNAF_BITS) {
int sign;
int even;
/* 4.1 4.4 */
u = secp256k1_scalar_shr_int(&s, w);
/* 4.2 */
even = ((u & 1) == 0);
sign = 2 * (u_last > 0) - 1;
u += sign * even;
u_last -= sign * even * (1 << w);
/* 4.3, adapted for global sign change */
wnaf[word++] = u_last * global_sign;
u_last = u;
}
wnaf[word] = u * global_sign;
VERIFY_CHECK(secp256k1_scalar_is_zero(&s));
VERIFY_CHECK(word == WNAF_SIZE(w));
return skew;
}
static void secp256k1_ecmult_const(secp256k1_gej *r, const secp256k1_ge *a, const secp256k1_scalar *scalar) {
secp256k1_ge pre_a[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_ge tmpa;
secp256k1_fe Z;
#ifdef USE_ENDOMORPHISM
secp256k1_ge pre_a_lam[ECMULT_TABLE_SIZE(WINDOW_A)];
int wnaf_1[1 + WNAF_SIZE(WINDOW_A - 1)];
int wnaf_lam[1 + WNAF_SIZE(WINDOW_A - 1)];
int skew_1;
int skew_lam;
secp256k1_scalar q_1, q_lam;
#else
int wnaf[1 + WNAF_SIZE(WINDOW_A - 1)];
#endif
int i;
secp256k1_scalar sc = *scalar;
/* build wnaf representation for q. */
#ifdef USE_ENDOMORPHISM
/* split q into q_1 and q_lam (where q = q_1 + q_lam*lambda, and q_1 and q_lam are ~128 bit) */
secp256k1_scalar_split_lambda(&q_1, &q_lam, &sc);
/* no need for zero correction when using endomorphism since even
* numbers have one added to them anyway */
skew_1 = secp256k1_wnaf_const(wnaf_1, q_1, WINDOW_A - 1);
skew_lam = secp256k1_wnaf_const(wnaf_lam, q_lam, WINDOW_A - 1);
#else
int is_zero = secp256k1_scalar_is_zero(scalar);
/* the wNAF ladder cannot handle zero, so bump this to one .. we will
* correct the result after the fact */
sc.d[0] += is_zero;
VERIFY_CHECK(!secp256k1_scalar_is_zero(&sc));
secp256k1_wnaf_const(wnaf, sc, WINDOW_A - 1);
#endif
/* Calculate odd multiples of a.
* All multiples are brought to the same Z 'denominator', which is stored
* in Z. Due to secp256k1' isomorphism we can do all operations pretending
* that the Z coordinate was 1, use affine addition formulae, and correct
* the Z coordinate of the result once at the end.
*/
secp256k1_gej_set_ge(r, a);
secp256k1_ecmult_odd_multiples_table_globalz_windowa(pre_a, &Z, r);
for (i = 0; i < ECMULT_TABLE_SIZE(WINDOW_A); i++) {
secp256k1_fe_normalize_weak(&pre_a[i].y);
}
#ifdef USE_ENDOMORPHISM
for (i = 0; i < ECMULT_TABLE_SIZE(WINDOW_A); i++) {
secp256k1_ge_mul_lambda(&pre_a_lam[i], &pre_a[i]);
}
#endif
/* first loop iteration (separated out so we can directly set r, rather
* than having it start at infinity, get doubled several times, then have
* its new value added to it) */
#ifdef USE_ENDOMORPHISM
i = wnaf_1[WNAF_SIZE(WINDOW_A - 1)];
VERIFY_CHECK(i != 0);
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a, i, WINDOW_A);
secp256k1_gej_set_ge(r, &tmpa);
i = wnaf_lam[WNAF_SIZE(WINDOW_A - 1)];
VERIFY_CHECK(i != 0);
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a_lam, i, WINDOW_A);
secp256k1_gej_add_ge(r, r, &tmpa);
#else
i = wnaf[WNAF_SIZE(WINDOW_A - 1)];
VERIFY_CHECK(i != 0);
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a, i, WINDOW_A);
secp256k1_gej_set_ge(r, &tmpa);
#endif
/* remaining loop iterations */
for (i = WNAF_SIZE(WINDOW_A - 1) - 1; i >= 0; i--) {
int n;
int j;
for (j = 0; j < WINDOW_A - 1; ++j) {
secp256k1_gej_double_nonzero(r, r, NULL);
}
#ifdef USE_ENDOMORPHISM
n = wnaf_1[i];
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a, n, WINDOW_A);
VERIFY_CHECK(n != 0);
secp256k1_gej_add_ge(r, r, &tmpa);
n = wnaf_lam[i];
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a_lam, n, WINDOW_A);
VERIFY_CHECK(n != 0);
secp256k1_gej_add_ge(r, r, &tmpa);
#else
n = wnaf[i];
VERIFY_CHECK(n != 0);
ECMULT_CONST_TABLE_GET_GE(&tmpa, pre_a, n, WINDOW_A);
secp256k1_gej_add_ge(r, r, &tmpa);
#endif
}
secp256k1_fe_mul(&r->z, &r->z, &Z);
#ifdef USE_ENDOMORPHISM
{
/* Correct for wNAF skew */
secp256k1_ge correction = *a;
secp256k1_ge_storage correction_1_stor;
secp256k1_ge_storage correction_lam_stor;
secp256k1_ge_storage a2_stor;
secp256k1_gej tmpj;
secp256k1_gej_set_ge(&tmpj, &correction);
secp256k1_gej_double_var(&tmpj, &tmpj, NULL);
secp256k1_ge_set_gej(&correction, &tmpj);
secp256k1_ge_to_storage(&correction_1_stor, a);
secp256k1_ge_to_storage(&correction_lam_stor, a);
secp256k1_ge_to_storage(&a2_stor, &correction);
/* For odd numbers this is 2a (so replace it), for even ones a (so no-op) */
secp256k1_ge_storage_cmov(&correction_1_stor, &a2_stor, skew_1 == 2);
secp256k1_ge_storage_cmov(&correction_lam_stor, &a2_stor, skew_lam == 2);
/* Apply the correction */
secp256k1_ge_from_storage(&correction, &correction_1_stor);
secp256k1_ge_neg(&correction, &correction);
secp256k1_gej_add_ge(r, r, &correction);
secp256k1_ge_from_storage(&correction, &correction_lam_stor);
secp256k1_ge_neg(&correction, &correction);
secp256k1_ge_mul_lambda(&correction, &correction);
secp256k1_gej_add_ge(r, r, &correction);
}
#else
/* correct for zero */
r->infinity |= is_zero;
#endif
}
#endif

@ -0,0 +1,43 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_GEN_
#define _SECP256K1_ECMULT_GEN_
#include "scalar.h"
#include "group.h"
typedef struct {
/* For accelerating the computation of a*G:
* To harden against timing attacks, use the following mechanism:
* * Break up the multiplicand into groups of 4 bits, called n_0, n_1, n_2, ..., n_63.
* * Compute sum(n_i * 16^i * G + U_i, i=0..63), where:
* * U_i = U * 2^i (for i=0..62)
* * U_i = U * (1-2^63) (for i=63)
* where U is a point with no known corresponding scalar. Note that sum(U_i, i=0..63) = 0.
* For each i, and each of the 16 possible values of n_i, (n_i * 16^i * G + U_i) is
* precomputed (call it prec(i, n_i)). The formula now becomes sum(prec(i, n_i), i=0..63).
* None of the resulting prec group elements have a known scalar, and neither do any of
* the intermediate sums while computing a*G.
*/
secp256k1_ge_storage (*prec)[64][16]; /* prec[j][i] = 16^j * i * G + U_i */
secp256k1_scalar blind;
secp256k1_gej initial;
} secp256k1_ecmult_gen_context;
static void secp256k1_ecmult_gen_context_init(secp256k1_ecmult_gen_context* ctx);
static void secp256k1_ecmult_gen_context_build(secp256k1_ecmult_gen_context* ctx, const secp256k1_callback* cb);
static void secp256k1_ecmult_gen_context_clone(secp256k1_ecmult_gen_context *dst,
const secp256k1_ecmult_gen_context* src, const secp256k1_callback* cb);
static void secp256k1_ecmult_gen_context_clear(secp256k1_ecmult_gen_context* ctx);
static int secp256k1_ecmult_gen_context_is_built(const secp256k1_ecmult_gen_context* ctx);
/** Multiply with the generator: R = a*G */
static void secp256k1_ecmult_gen(const secp256k1_ecmult_gen_context* ctx, secp256k1_gej *r, const secp256k1_scalar *a);
static void secp256k1_ecmult_gen_blind(secp256k1_ecmult_gen_context *ctx, const unsigned char *seed32);
#endif

@ -0,0 +1,205 @@
/**********************************************************************
* Copyright (c) 2013, 2014, 2015 Pieter Wuille, Gregory Maxwell *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_GEN_IMPL_H_
#define _SECP256K1_ECMULT_GEN_IMPL_H_
#include "scalar.h"
#include "group.h"
#include "ecmult_gen.h"
#include "hash_impl.h"
#ifdef USE_ECMULT_STATIC_PRECOMPUTATION
#include "ecmult_static_context.h"
#endif
static void secp256k1_ecmult_gen_context_init(secp256k1_ecmult_gen_context *ctx) {
ctx->prec = NULL;
}
static void secp256k1_ecmult_gen_context_build(secp256k1_ecmult_gen_context *ctx, const secp256k1_callback* cb) {
#ifndef USE_ECMULT_STATIC_PRECOMPUTATION
secp256k1_ge prec[1024];
secp256k1_gej gj;
secp256k1_gej nums_gej;
int i, j;
#endif
if (ctx->prec != NULL) {
return;
}
#ifndef USE_ECMULT_STATIC_PRECOMPUTATION
ctx->prec = (secp256k1_ge_storage (*)[64][16])checked_malloc(cb, sizeof(*ctx->prec));
/* get the generator */
secp256k1_gej_set_ge(&gj, &secp256k1_ge_const_g);
/* Construct a group element with no known corresponding scalar (nothing up my sleeve). */
{
static const unsigned char nums_b32[33] = "The scalar for this x is unknown";
secp256k1_fe nums_x;
secp256k1_ge nums_ge;
VERIFY_CHECK(secp256k1_fe_set_b32(&nums_x, nums_b32));
VERIFY_CHECK(secp256k1_ge_set_xo_var(&nums_ge, &nums_x, 0));
secp256k1_gej_set_ge(&nums_gej, &nums_ge);
/* Add G to make the bits in x uniformly distributed. */
secp256k1_gej_add_ge_var(&nums_gej, &nums_gej, &secp256k1_ge_const_g, NULL);
}
/* compute prec. */
{
secp256k1_gej precj[1024]; /* Jacobian versions of prec. */
secp256k1_gej gbase;
secp256k1_gej numsbase;
gbase = gj; /* 16^j * G */
numsbase = nums_gej; /* 2^j * nums. */
for (j = 0; j < 64; j++) {
/* Set precj[j*16 .. j*16+15] to (numsbase, numsbase + gbase, ..., numsbase + 15*gbase). */
precj[j*16] = numsbase;
for (i = 1; i < 16; i++) {
secp256k1_gej_add_var(&precj[j*16 + i], &precj[j*16 + i - 1], &gbase, NULL);
}
/* Multiply gbase by 16. */
for (i = 0; i < 4; i++) {
secp256k1_gej_double_var(&gbase, &gbase, NULL);
}
/* Multiply numbase by 2. */
secp256k1_gej_double_var(&numsbase, &numsbase, NULL);
if (j == 62) {
/* In the last iteration, numsbase is (1 - 2^j) * nums instead. */
secp256k1_gej_neg(&numsbase, &numsbase);
secp256k1_gej_add_var(&numsbase, &numsbase, &nums_gej, NULL);
}
}
secp256k1_ge_set_all_gej_var(1024, prec, precj, cb);
}
for (j = 0; j < 64; j++) {
for (i = 0; i < 16; i++) {
secp256k1_ge_to_storage(&(*ctx->prec)[j][i], &prec[j*16 + i]);
}
}
#else
(void)cb;
ctx->prec = (secp256k1_ge_storage (*)[64][16])secp256k1_ecmult_static_context;
#endif
secp256k1_ecmult_gen_blind(ctx, NULL);
}
static int secp256k1_ecmult_gen_context_is_built(const secp256k1_ecmult_gen_context* ctx) {
return ctx->prec != NULL;
}
static void secp256k1_ecmult_gen_context_clone(secp256k1_ecmult_gen_context *dst,
const secp256k1_ecmult_gen_context *src, const secp256k1_callback* cb) {
if (src->prec == NULL) {
dst->prec = NULL;
} else {
#ifndef USE_ECMULT_STATIC_PRECOMPUTATION
dst->prec = (secp256k1_ge_storage (*)[64][16])checked_malloc(cb, sizeof(*dst->prec));
memcpy(dst->prec, src->prec, sizeof(*dst->prec));
#else
(void)cb;
dst->prec = src->prec;
#endif
dst->initial = src->initial;
dst->blind = src->blind;
}
}
static void secp256k1_ecmult_gen_context_clear(secp256k1_ecmult_gen_context *ctx) {
#ifndef USE_ECMULT_STATIC_PRECOMPUTATION
free(ctx->prec);
#endif
secp256k1_scalar_clear(&ctx->blind);
secp256k1_gej_clear(&ctx->initial);
ctx->prec = NULL;
}
static void secp256k1_ecmult_gen(const secp256k1_ecmult_gen_context *ctx, secp256k1_gej *r, const secp256k1_scalar *gn) {
secp256k1_ge add;
secp256k1_ge_storage adds;
secp256k1_scalar gnb;
int bits;
int i, j;
memset(&adds, 0, sizeof(adds));
*r = ctx->initial;
/* Blind scalar/point multiplication by computing (n-b)G + bG instead of nG. */
secp256k1_scalar_add(&gnb, gn, &ctx->blind);
add.infinity = 0;
for (j = 0; j < 64; j++) {
bits = secp256k1_scalar_get_bits(&gnb, j * 4, 4);
for (i = 0; i < 16; i++) {
/** This uses a conditional move to avoid any secret data in array indexes.
* _Any_ use of secret indexes has been demonstrated to result in timing
* sidechannels, even when the cache-line access patterns are uniform.
* See also:
* "A word of warning", CHES 2013 Rump Session, by Daniel J. Bernstein and Peter Schwabe
* (https://cryptojedi.org/peter/data/chesrump-20130822.pdf) and
* "Cache Attacks and Countermeasures: the Case of AES", RSA 2006,
* by Dag Arne Osvik, Adi Shamir, and Eran Tromer
* (http://www.tau.ac.il/~tromer/papers/cache.pdf)
*/
secp256k1_ge_storage_cmov(&adds, &(*ctx->prec)[j][i], i == bits);
}
secp256k1_ge_from_storage(&add, &adds);
secp256k1_gej_add_ge(r, r, &add);
}
bits = 0;
secp256k1_ge_clear(&add);
secp256k1_scalar_clear(&gnb);
}
/* Setup blinding values for secp256k1_ecmult_gen. */
static void secp256k1_ecmult_gen_blind(secp256k1_ecmult_gen_context *ctx, const unsigned char *seed32) {
secp256k1_scalar b;
secp256k1_gej gb;
secp256k1_fe s;
unsigned char nonce32[32];
secp256k1_rfc6979_hmac_sha256_t rng;
int retry;
unsigned char keydata[64] = {0};
if (seed32 == NULL) {
/* When seed is NULL, reset the initial point and blinding value. */
secp256k1_gej_set_ge(&ctx->initial, &secp256k1_ge_const_g);
secp256k1_gej_neg(&ctx->initial, &ctx->initial);
secp256k1_scalar_set_int(&ctx->blind, 1);
}
/* The prior blinding value (if not reset) is chained forward by including it in the hash. */
secp256k1_scalar_get_b32(nonce32, &ctx->blind);
/** Using a CSPRNG allows a failure free interface, avoids needing large amounts of random data,
* and guards against weak or adversarial seeds. This is a simpler and safer interface than
* asking the caller for blinding values directly and expecting them to retry on failure.
*/
memcpy(keydata, nonce32, 32);
if (seed32 != NULL) {
memcpy(keydata + 32, seed32, 32);
}
secp256k1_rfc6979_hmac_sha256_initialize(&rng, keydata, seed32 ? 64 : 32);
memset(keydata, 0, sizeof(keydata));
/* Retry for out of range results to achieve uniformity. */
do {
secp256k1_rfc6979_hmac_sha256_generate(&rng, nonce32, 32);
retry = !secp256k1_fe_set_b32(&s, nonce32);
retry |= secp256k1_fe_is_zero(&s);
} while (retry);
/* Randomize the projection to defend against multiplier sidechannels. */
secp256k1_gej_rescale(&ctx->initial, &s);
secp256k1_fe_clear(&s);
do {
secp256k1_rfc6979_hmac_sha256_generate(&rng, nonce32, 32);
secp256k1_scalar_set_b32(&b, nonce32, &retry);
/* A blinding value of 0 works, but would undermine the projection hardening. */
retry |= secp256k1_scalar_is_zero(&b);
} while (retry);
secp256k1_rfc6979_hmac_sha256_finalize(&rng);
memset(nonce32, 0, 32);
secp256k1_ecmult_gen(ctx, &gb, &b);
secp256k1_scalar_negate(&b, &b);
ctx->blind = b;
ctx->initial = gb;
secp256k1_scalar_clear(&b);
secp256k1_gej_clear(&gb);
}
#endif

@ -0,0 +1,389 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_IMPL_H_
#define _SECP256K1_ECMULT_IMPL_H_
#include "group.h"
#include "scalar.h"
#include "ecmult.h"
/* optimal for 128-bit and 256-bit exponents. */
#define WINDOW_A 5
/** larger numbers may result in slightly better performance, at the cost of
exponentially larger precomputed tables. */
#ifdef USE_ENDOMORPHISM
/** Two tables for window size 15: 1.375 MiB. */
#define WINDOW_G 15
#else
/** One table for window size 16: 1.375 MiB. */
#define WINDOW_G 16
#endif
/** The number of entries a table with precomputed multiples needs to have. */
#define ECMULT_TABLE_SIZE(w) (1 << ((w)-2))
/** Fill a table 'prej' with precomputed odd multiples of a. Prej will contain
* the values [1*a,3*a,...,(2*n-1)*a], so it space for n values. zr[0] will
* contain prej[0].z / a.z. The other zr[i] values = prej[i].z / prej[i-1].z.
* Prej's Z values are undefined, except for the last value.
*/
static void secp256k1_ecmult_odd_multiples_table(int n, secp256k1_gej *prej, secp256k1_fe *zr, const secp256k1_gej *a) {
secp256k1_gej d;
secp256k1_ge a_ge, d_ge;
int i;
VERIFY_CHECK(!a->infinity);
secp256k1_gej_double_var(&d, a, NULL);
/*
* Perform the additions on an isomorphism where 'd' is affine: drop the z coordinate
* of 'd', and scale the 1P starting value's x/y coordinates without changing its z.
*/
d_ge.x = d.x;
d_ge.y = d.y;
d_ge.infinity = 0;
secp256k1_ge_set_gej_zinv(&a_ge, a, &d.z);
prej[0].x = a_ge.x;
prej[0].y = a_ge.y;
prej[0].z = a->z;
prej[0].infinity = 0;
zr[0] = d.z;
for (i = 1; i < n; i++) {
secp256k1_gej_add_ge_var(&prej[i], &prej[i-1], &d_ge, &zr[i]);
}
/*
* Each point in 'prej' has a z coordinate too small by a factor of 'd.z'. Only
* the final point's z coordinate is actually used though, so just update that.
*/
secp256k1_fe_mul(&prej[n-1].z, &prej[n-1].z, &d.z);
}
/** Fill a table 'pre' with precomputed odd multiples of a.
*
* There are two versions of this function:
* - secp256k1_ecmult_odd_multiples_table_globalz_windowa which brings its
* resulting point set to a single constant Z denominator, stores the X and Y
* coordinates as ge_storage points in pre, and stores the global Z in rz.
* It only operates on tables sized for WINDOW_A wnaf multiples.
* - secp256k1_ecmult_odd_multiples_table_storage_var, which converts its
* resulting point set to actually affine points, and stores those in pre.
* It operates on tables of any size, but uses heap-allocated temporaries.
*
* To compute a*P + b*G, we compute a table for P using the first function,
* and for G using the second (which requires an inverse, but it only needs to
* happen once).
*/
static void secp256k1_ecmult_odd_multiples_table_globalz_windowa(secp256k1_ge *pre, secp256k1_fe *globalz, const secp256k1_gej *a) {
secp256k1_gej prej[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_fe zr[ECMULT_TABLE_SIZE(WINDOW_A)];
/* Compute the odd multiples in Jacobian form. */
secp256k1_ecmult_odd_multiples_table(ECMULT_TABLE_SIZE(WINDOW_A), prej, zr, a);
/* Bring them to the same Z denominator. */
secp256k1_ge_globalz_set_table_gej(ECMULT_TABLE_SIZE(WINDOW_A), pre, globalz, prej, zr);
}
static void secp256k1_ecmult_odd_multiples_table_storage_var(int n, secp256k1_ge_storage *pre, const secp256k1_gej *a, const secp256k1_callback *cb) {
secp256k1_gej *prej = (secp256k1_gej*)checked_malloc(cb, sizeof(secp256k1_gej) * n);
secp256k1_ge *prea = (secp256k1_ge*)checked_malloc(cb, sizeof(secp256k1_ge) * n);
secp256k1_fe *zr = (secp256k1_fe*)checked_malloc(cb, sizeof(secp256k1_fe) * n);
int i;
/* Compute the odd multiples in Jacobian form. */
secp256k1_ecmult_odd_multiples_table(n, prej, zr, a);
/* Convert them in batch to affine coordinates. */
secp256k1_ge_set_table_gej_var(n, prea, prej, zr);
/* Convert them to compact storage form. */
for (i = 0; i < n; i++) {
secp256k1_ge_to_storage(&pre[i], &prea[i]);
}
free(prea);
free(prej);
free(zr);
}
/** The following two macro retrieves a particular odd multiple from a table
* of precomputed multiples. */
#define ECMULT_TABLE_GET_GE(r,pre,n,w) do { \
VERIFY_CHECK(((n) & 1) == 1); \
VERIFY_CHECK((n) >= -((1 << ((w)-1)) - 1)); \
VERIFY_CHECK((n) <= ((1 << ((w)-1)) - 1)); \
if ((n) > 0) { \
*(r) = (pre)[((n)-1)/2]; \
} else { \
secp256k1_ge_neg((r), &(pre)[(-(n)-1)/2]); \
} \
} while(0)
#define ECMULT_TABLE_GET_GE_STORAGE(r,pre,n,w) do { \
VERIFY_CHECK(((n) & 1) == 1); \
VERIFY_CHECK((n) >= -((1 << ((w)-1)) - 1)); \
VERIFY_CHECK((n) <= ((1 << ((w)-1)) - 1)); \
if ((n) > 0) { \
secp256k1_ge_from_storage((r), &(pre)[((n)-1)/2]); \
} else { \
secp256k1_ge_from_storage((r), &(pre)[(-(n)-1)/2]); \
secp256k1_ge_neg((r), (r)); \
} \
} while(0)
static void secp256k1_ecmult_context_init(secp256k1_ecmult_context *ctx) {
ctx->pre_g = NULL;
#ifdef USE_ENDOMORPHISM
ctx->pre_g_128 = NULL;
#endif
}
static void secp256k1_ecmult_context_build(secp256k1_ecmult_context *ctx, const secp256k1_callback *cb) {
secp256k1_gej gj;
if (ctx->pre_g != NULL) {
return;
}
/* get the generator */
secp256k1_gej_set_ge(&gj, &secp256k1_ge_const_g);
ctx->pre_g = (secp256k1_ge_storage (*)[])checked_malloc(cb, sizeof((*ctx->pre_g)[0]) * ECMULT_TABLE_SIZE(WINDOW_G));
/* precompute the tables with odd multiples */
secp256k1_ecmult_odd_multiples_table_storage_var(ECMULT_TABLE_SIZE(WINDOW_G), *ctx->pre_g, &gj, cb);
#ifdef USE_ENDOMORPHISM
{
secp256k1_gej g_128j;
int i;
ctx->pre_g_128 = (secp256k1_ge_storage (*)[])checked_malloc(cb, sizeof((*ctx->pre_g_128)[0]) * ECMULT_TABLE_SIZE(WINDOW_G));
/* calculate 2^128*generator */
g_128j = gj;
for (i = 0; i < 128; i++) {
secp256k1_gej_double_var(&g_128j, &g_128j, NULL);
}
secp256k1_ecmult_odd_multiples_table_storage_var(ECMULT_TABLE_SIZE(WINDOW_G), *ctx->pre_g_128, &g_128j, cb);
}
#endif
}
static void secp256k1_ecmult_context_clone(secp256k1_ecmult_context *dst,
const secp256k1_ecmult_context *src, const secp256k1_callback *cb) {
if (src->pre_g == NULL) {
dst->pre_g = NULL;
} else {
size_t size = sizeof((*dst->pre_g)[0]) * ECMULT_TABLE_SIZE(WINDOW_G);
dst->pre_g = (secp256k1_ge_storage (*)[])checked_malloc(cb, size);
memcpy(dst->pre_g, src->pre_g, size);
}
#ifdef USE_ENDOMORPHISM
if (src->pre_g_128 == NULL) {
dst->pre_g_128 = NULL;
} else {
size_t size = sizeof((*dst->pre_g_128)[0]) * ECMULT_TABLE_SIZE(WINDOW_G);
dst->pre_g_128 = (secp256k1_ge_storage (*)[])checked_malloc(cb, size);
memcpy(dst->pre_g_128, src->pre_g_128, size);
}
#endif
}
static int secp256k1_ecmult_context_is_built(const secp256k1_ecmult_context *ctx) {
return ctx->pre_g != NULL;
}
static void secp256k1_ecmult_context_clear(secp256k1_ecmult_context *ctx) {
free(ctx->pre_g);
#ifdef USE_ENDOMORPHISM
free(ctx->pre_g_128);
#endif
secp256k1_ecmult_context_init(ctx);
}
/** Convert a number to WNAF notation. The number becomes represented by sum(2^i * wnaf[i], i=0..bits),
* with the following guarantees:
* - each wnaf[i] is either 0, or an odd integer between -(1<<(w-1) - 1) and (1<<(w-1) - 1)
* - two non-zero entries in wnaf are separated by at least w-1 zeroes.
* - the number of set values in wnaf is returned. This number is at most 256, and at most one more
* than the number of bits in the (absolute value) of the input.
*/
static int secp256k1_ecmult_wnaf(int *wnaf, int len, const secp256k1_scalar *a, int w) {
secp256k1_scalar s = *a;
int last_set_bit = -1;
int bit = 0;
int sign = 1;
int carry = 0;
VERIFY_CHECK(wnaf != NULL);
VERIFY_CHECK(0 <= len && len <= 256);
VERIFY_CHECK(a != NULL);
VERIFY_CHECK(2 <= w && w <= 31);
memset(wnaf, 0, len * sizeof(wnaf[0]));
if (secp256k1_scalar_get_bits(&s, 255, 1)) {
secp256k1_scalar_negate(&s, &s);
sign = -1;
}
while (bit < len) {
int now;
int word;
if (secp256k1_scalar_get_bits(&s, bit, 1) == (unsigned int)carry) {
bit++;
continue;
}
now = w;
if (now > len - bit) {
now = len - bit;
}
word = secp256k1_scalar_get_bits_var(&s, bit, now) + carry;
carry = (word >> (w-1)) & 1;
word -= carry << w;
wnaf[bit] = sign * word;
last_set_bit = bit;
bit += now;
}
#ifdef VERIFY
CHECK(carry == 0);
while (bit < 256) {
CHECK(secp256k1_scalar_get_bits(&s, bit++, 1) == 0);
}
#endif
return last_set_bit + 1;
}
static void secp256k1_ecmult(const secp256k1_ecmult_context *ctx, secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_scalar *na, const secp256k1_scalar *ng) {
secp256k1_ge pre_a[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_ge tmpa;
secp256k1_fe Z;
#ifdef USE_ENDOMORPHISM
secp256k1_ge pre_a_lam[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_scalar na_1, na_lam;
/* Splitted G factors. */
secp256k1_scalar ng_1, ng_128;
int wnaf_na_1[130];
int wnaf_na_lam[130];
int bits_na_1;
int bits_na_lam;
int wnaf_ng_1[129];
int bits_ng_1;
int wnaf_ng_128[129];
int bits_ng_128;
#else
int wnaf_na[256];
int bits_na;
int wnaf_ng[256];
int bits_ng;
#endif
int i;
int bits;
#ifdef USE_ENDOMORPHISM
/* split na into na_1 and na_lam (where na = na_1 + na_lam*lambda, and na_1 and na_lam are ~128 bit) */
secp256k1_scalar_split_lambda(&na_1, &na_lam, na);
/* build wnaf representation for na_1 and na_lam. */
bits_na_1 = secp256k1_ecmult_wnaf(wnaf_na_1, 130, &na_1, WINDOW_A);
bits_na_lam = secp256k1_ecmult_wnaf(wnaf_na_lam, 130, &na_lam, WINDOW_A);
VERIFY_CHECK(bits_na_1 <= 130);
VERIFY_CHECK(bits_na_lam <= 130);
bits = bits_na_1;
if (bits_na_lam > bits) {
bits = bits_na_lam;
}
#else
/* build wnaf representation for na. */
bits_na = secp256k1_ecmult_wnaf(wnaf_na, 256, na, WINDOW_A);
bits = bits_na;
#endif
/* Calculate odd multiples of a.
* All multiples are brought to the same Z 'denominator', which is stored
* in Z. Due to secp256k1' isomorphism we can do all operations pretending
* that the Z coordinate was 1, use affine addition formulae, and correct
* the Z coordinate of the result once at the end.
* The exception is the precomputed G table points, which are actually
* affine. Compared to the base used for other points, they have a Z ratio
* of 1/Z, so we can use secp256k1_gej_add_zinv_var, which uses the same
* isomorphism to efficiently add with a known Z inverse.
*/
secp256k1_ecmult_odd_multiples_table_globalz_windowa(pre_a, &Z, a);
#ifdef USE_ENDOMORPHISM
for (i = 0; i < ECMULT_TABLE_SIZE(WINDOW_A); i++) {
secp256k1_ge_mul_lambda(&pre_a_lam[i], &pre_a[i]);
}
/* split ng into ng_1 and ng_128 (where gn = gn_1 + gn_128*2^128, and gn_1 and gn_128 are ~128 bit) */
secp256k1_scalar_split_128(&ng_1, &ng_128, ng);
/* Build wnaf representation for ng_1 and ng_128 */
bits_ng_1 = secp256k1_ecmult_wnaf(wnaf_ng_1, 129, &ng_1, WINDOW_G);
bits_ng_128 = secp256k1_ecmult_wnaf(wnaf_ng_128, 129, &ng_128, WINDOW_G);
if (bits_ng_1 > bits) {
bits = bits_ng_1;
}
if (bits_ng_128 > bits) {
bits = bits_ng_128;
}
#else
bits_ng = secp256k1_ecmult_wnaf(wnaf_ng, 256, ng, WINDOW_G);
if (bits_ng > bits) {
bits = bits_ng;
}
#endif
secp256k1_gej_set_infinity(r);
for (i = bits - 1; i >= 0; i--) {
int n;
secp256k1_gej_double_var(r, r, NULL);
#ifdef USE_ENDOMORPHISM
if (i < bits_na_1 && (n = wnaf_na_1[i])) {
ECMULT_TABLE_GET_GE(&tmpa, pre_a, n, WINDOW_A);
secp256k1_gej_add_ge_var(r, r, &tmpa, NULL);
}
if (i < bits_na_lam && (n = wnaf_na_lam[i])) {
ECMULT_TABLE_GET_GE(&tmpa, pre_a_lam, n, WINDOW_A);
secp256k1_gej_add_ge_var(r, r, &tmpa, NULL);
}
if (i < bits_ng_1 && (n = wnaf_ng_1[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, *ctx->pre_g, n, WINDOW_G);
secp256k1_gej_add_zinv_var(r, r, &tmpa, &Z);
}
if (i < bits_ng_128 && (n = wnaf_ng_128[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, *ctx->pre_g_128, n, WINDOW_G);
secp256k1_gej_add_zinv_var(r, r, &tmpa, &Z);
}
#else
if (i < bits_na && (n = wnaf_na[i])) {
ECMULT_TABLE_GET_GE(&tmpa, pre_a, n, WINDOW_A);
secp256k1_gej_add_ge_var(r, r, &tmpa, NULL);
}
if (i < bits_ng && (n = wnaf_ng[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, *ctx->pre_g, n, WINDOW_G);
secp256k1_gej_add_zinv_var(r, r, &tmpa, &Z);
}
#endif
}
if (!r->infinity) {
secp256k1_fe_mul(&r->z, &r->z, &Z);
}
}
#endif

@ -31,86 +31,89 @@
#endif
/** Normalize a field element. */
static void secp256k1_fe_normalize(secp256k1_fe_t *r);
static void secp256k1_fe_normalize(secp256k1_fe *r);
/** Weakly normalize a field element: reduce it magnitude to 1, but don't fully normalize. */
static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r);
static void secp256k1_fe_normalize_weak(secp256k1_fe *r);
/** Normalize a field element, without constant-time guarantee. */
static void secp256k1_fe_normalize_var(secp256k1_fe_t *r);
static void secp256k1_fe_normalize_var(secp256k1_fe *r);
/** Verify whether a field element represents zero i.e. would normalize to a zero value. The field
* implementation may optionally normalize the input, but this should not be relied upon. */
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r);
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe *r);
/** Verify whether a field element represents zero i.e. would normalize to a zero value. The field
* implementation may optionally normalize the input, but this should not be relied upon. */
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r);
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe *r);
/** Set a field element equal to a small integer. Resulting field element is normalized. */
static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a);
static void secp256k1_fe_set_int(secp256k1_fe *r, int a);
/** Verify whether a field element is zero. Requires the input to be normalized. */
static int secp256k1_fe_is_zero(const secp256k1_fe_t *a);
static int secp256k1_fe_is_zero(const secp256k1_fe *a);
/** Check the "oddness" of a field element. Requires the input to be normalized. */
static int secp256k1_fe_is_odd(const secp256k1_fe_t *a);
static int secp256k1_fe_is_odd(const secp256k1_fe *a);
/** Compare two field elements. Requires magnitude-1 inputs. */
static int secp256k1_fe_equal_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b);
static int secp256k1_fe_equal_var(const secp256k1_fe *a, const secp256k1_fe *b);
/** Compare two field elements. Requires both inputs to be normalized */
static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b);
static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b);
/** Set a field element equal to 32-byte big endian value. If succesful, the resulting field element is normalized. */
static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a);
/** Set a field element equal to 32-byte big endian value. If successful, the resulting field element is normalized. */
static int secp256k1_fe_set_b32(secp256k1_fe *r, const unsigned char *a);
/** Convert a field element to a 32-byte big endian value. Requires the input to be normalized */
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a);
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe *a);
/** Set a field element equal to the additive inverse of another. Takes a maximum magnitude of the input
* as an argument. The magnitude of the output is one higher. */
static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp256k1_fe_t *a, int m);
static void secp256k1_fe_negate(secp256k1_fe *r, const secp256k1_fe *a, int m);
/** Multiplies the passed field element with a small integer constant. Multiplies the magnitude by that
* small integer. */
static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a);
static void secp256k1_fe_mul_int(secp256k1_fe *r, int a);
/** Adds a field element to another. The result has the sum of the inputs' magnitudes as magnitude. */
static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1_fe_t *a);
static void secp256k1_fe_add(secp256k1_fe *r, const secp256k1_fe *a);
/** Sets a field element to be the product of two others. Requires the inputs' magnitudes to be at most 8.
* The output magnitude is 1 (but not guaranteed to be normalized). */
static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const secp256k1_fe_t * SECP256K1_RESTRICT b);
static void secp256k1_fe_mul(secp256k1_fe *r, const secp256k1_fe *a, const secp256k1_fe * SECP256K1_RESTRICT b);
/** Sets a field element to be the square of another. Requires the input's magnitude to be at most 8.
* The output magnitude is 1 (but not guaranteed to be normalized). */
static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a);
static void secp256k1_fe_sqr(secp256k1_fe *r, const secp256k1_fe *a);
/** Sets a field element to be the (modular) square root (if any exist) of another. Requires the
* input's magnitude to be at most 8. The output magnitude is 1 (but not guaranteed to be
* normalized). Return value indicates whether a square root was found. */
static int secp256k1_fe_sqrt_var(secp256k1_fe_t *r, const secp256k1_fe_t *a);
static int secp256k1_fe_sqrt_var(secp256k1_fe *r, const secp256k1_fe *a);
/** Sets a field element to be the (modular) inverse of another. Requires the input's magnitude to be
* at most 8. The output magnitude is 1 (but not guaranteed to be normalized). */
static void secp256k1_fe_inv(secp256k1_fe_t *r, const secp256k1_fe_t *a);
static void secp256k1_fe_inv(secp256k1_fe *r, const secp256k1_fe *a);
/** Potentially faster version of secp256k1_fe_inv, without constant-time guarantee. */
static void secp256k1_fe_inv_var(secp256k1_fe_t *r, const secp256k1_fe_t *a);
static void secp256k1_fe_inv_var(secp256k1_fe *r, const secp256k1_fe *a);
/** Calculate the (modular) inverses of a batch of field elements. Requires the inputs' magnitudes to be
* at most 8. The output magnitudes are 1 (but not guaranteed to be normalized). The inputs and
* outputs must not overlap in memory. */
static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe_t *r, const secp256k1_fe_t *a);
static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe *r, const secp256k1_fe *a);
/** Convert a field element to the storage type. */
static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_fe_t*);
static void secp256k1_fe_to_storage(secp256k1_fe_storage *r, const secp256k1_fe *a);
/** Convert a field element back from the storage type. */
static void secp256k1_fe_from_storage(secp256k1_fe_t *r, const secp256k1_fe_storage_t*);
static void secp256k1_fe_from_storage(secp256k1_fe *r, const secp256k1_fe_storage *a);
/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */
static void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r, const secp256k1_fe_storage_t *a, int flag);
static void secp256k1_fe_storage_cmov(secp256k1_fe_storage *r, const secp256k1_fe_storage *a, int flag);
/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */
static void secp256k1_fe_cmov(secp256k1_fe *r, const secp256k1_fe *a, int flag);
#endif

@ -16,20 +16,20 @@ typedef struct {
int magnitude;
int normalized;
#endif
} secp256k1_fe_t;
} secp256k1_fe;
/* Unpacks a constant into a overlapping multi-limbed FE element. */
#define SECP256K1_FE_CONST_INNER(d7, d6, d5, d4, d3, d2, d1, d0) { \
(d0) & 0x3FFFFFFUL, \
((d0) >> 26) | ((d1) & 0xFFFFFUL) << 6, \
((d1) >> 20) | ((d2) & 0x3FFFUL) << 12, \
((d2) >> 14) | ((d3) & 0xFFUL) << 18, \
((d3) >> 8) | ((d4) & 0x3) << 24, \
((d4) >> 2) & 0x3FFFFFFUL, \
((d4) >> 28) | ((d5) & 0x3FFFFFUL) << 4, \
((d5) >> 22) | ((d6) & 0xFFFF) << 10, \
((d6) >> 16) | ((d7) & 0x3FF) << 16, \
((d7) >> 10) \
(((uint32_t)d0) >> 26) | (((uint32_t)(d1) & 0xFFFFFUL) << 6), \
(((uint32_t)d1) >> 20) | (((uint32_t)(d2) & 0x3FFFUL) << 12), \
(((uint32_t)d2) >> 14) | (((uint32_t)(d3) & 0xFFUL) << 18), \
(((uint32_t)d3) >> 8) | (((uint32_t)(d4) & 0x3UL) << 24), \
(((uint32_t)d4) >> 2) & 0x3FFFFFFUL, \
(((uint32_t)d4) >> 28) | (((uint32_t)(d5) & 0x3FFFFFUL) << 4), \
(((uint32_t)d5) >> 22) | (((uint32_t)(d6) & 0xFFFFUL) << 10), \
(((uint32_t)d6) >> 16) | (((uint32_t)(d7) & 0x3FFUL) << 16), \
(((uint32_t)d7) >> 10) \
}
#ifdef VERIFY
@ -40,8 +40,8 @@ typedef struct {
typedef struct {
uint32_t n[8];
} secp256k1_fe_storage_t;
} secp256k1_fe_storage;
#define SECP256K1_FE_STORAGE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{ (d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) }}
#define SECP256K1_FE_STORAGE_CONST_GET(d) d.n[7], d.n[6], d.n[5], d.n[4],d.n[3], d.n[2], d.n[1], d.n[0]
#endif

@ -14,7 +14,7 @@
#include "field.h"
#ifdef VERIFY
static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
static void secp256k1_fe_verify(const secp256k1_fe *a) {
const uint32_t *d = a->n;
int m = a->normalized ? 1 : 2 * a->magnitude, r = 1;
r &= (d[0] <= 0x3FFFFFFUL * m);
@ -41,12 +41,12 @@ static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
VERIFY_CHECK(r == 1);
}
#else
static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
static void secp256k1_fe_verify(const secp256k1_fe *a) {
(void)a;
}
#endif
static void secp256k1_fe_normalize(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize(secp256k1_fe *r) {
uint32_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
@ -101,7 +101,7 @@ static void secp256k1_fe_normalize(secp256k1_fe_t *r) {
#endif
}
static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize_weak(secp256k1_fe *r) {
uint32_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
@ -132,7 +132,7 @@ static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r) {
#endif
}
static void secp256k1_fe_normalize_var(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize_var(secp256k1_fe *r) {
uint32_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
@ -188,7 +188,7 @@ static void secp256k1_fe_normalize_var(secp256k1_fe_t *r) {
#endif
}
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe *r) {
uint32_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
@ -217,7 +217,7 @@ static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
return (z0 == 0) | (z1 == 0x3FFFFFFUL);
}
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe *r) {
uint32_t t0, t1, t2, t3, t4, t5, t6, t7, t8, t9;
uint32_t z0, z1;
uint32_t x;
@ -252,7 +252,7 @@ static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
t9 &= 0x03FFFFFUL;
t1 += (x << 6);
t1 += (t0 >> 26); t0 = z0;
t1 += (t0 >> 26);
t2 += (t1 >> 26); t1 &= 0x3FFFFFFUL; z0 |= t1; z1 &= t1 ^ 0x40UL;
t3 += (t2 >> 26); t2 &= 0x3FFFFFFUL; z0 |= t2; z1 &= t2;
t4 += (t3 >> 26); t3 &= 0x3FFFFFFUL; z0 |= t3; z1 &= t3;
@ -269,7 +269,7 @@ static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
return (z0 == 0) | (z1 == 0x3FFFFFFUL);
}
SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a) {
SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe *r, int a) {
r->n[0] = a;
r->n[1] = r->n[2] = r->n[3] = r->n[4] = r->n[5] = r->n[6] = r->n[7] = r->n[8] = r->n[9] = 0;
#ifdef VERIFY
@ -279,7 +279,7 @@ SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a) {
#endif
}
SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe_t *a) {
SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe *a) {
const uint32_t *t = a->n;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -288,7 +288,7 @@ SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe_t *a) {
return (t[0] | t[1] | t[2] | t[3] | t[4] | t[5] | t[6] | t[7] | t[8] | t[9]) == 0;
}
SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe_t *a) {
SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
secp256k1_fe_verify(a);
@ -296,7 +296,7 @@ SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe_t *a) {
return a->n[0] & 1;
}
SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe_t *a) {
SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe *a) {
int i;
#ifdef VERIFY
a->magnitude = 0;
@ -307,7 +307,7 @@ SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe_t *a) {
}
}
static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b) {
static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -326,7 +326,7 @@ static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b
return 0;
}
static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
static int secp256k1_fe_set_b32(secp256k1_fe *r, const unsigned char *a) {
int i;
r->n[0] = r->n[1] = r->n[2] = r->n[3] = r->n[4] = 0;
r->n[5] = r->n[6] = r->n[7] = r->n[8] = r->n[9] = 0;
@ -350,7 +350,7 @@ static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
}
/** Convert a field element to a 32-byte big endian value. Requires the input to be normalized */
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe *a) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -368,7 +368,7 @@ static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a) {
}
}
SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp256k1_fe_t *a, int m) {
SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe *r, const secp256k1_fe *a, int m) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= m);
secp256k1_fe_verify(a);
@ -390,7 +390,7 @@ SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp25
#endif
}
SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a) {
SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe *r, int a) {
r->n[0] *= a;
r->n[1] *= a;
r->n[2] *= a;
@ -408,7 +408,7 @@ SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a) {
#endif
}
SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe *r, const secp256k1_fe *a) {
#ifdef VERIFY
secp256k1_fe_verify(a);
#endif
@ -1039,7 +1039,7 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
}
static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const secp256k1_fe_t * SECP256K1_RESTRICT b) {
static void secp256k1_fe_mul(secp256k1_fe *r, const secp256k1_fe *a, const secp256k1_fe * SECP256K1_RESTRICT b) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= 8);
VERIFY_CHECK(b->magnitude <= 8);
@ -1055,7 +1055,7 @@ static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const s
#endif
}
static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_sqr(secp256k1_fe *r, const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= 8);
secp256k1_fe_verify(a);
@ -1068,7 +1068,29 @@ static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
#endif
}
static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r, const secp256k1_fe_storage_t *a, int flag) {
static SECP256K1_INLINE void secp256k1_fe_cmov(secp256k1_fe *r, const secp256k1_fe *a, int flag) {
uint32_t mask0, mask1;
mask0 = flag + ~((uint32_t)0);
mask1 = ~mask0;
r->n[0] = (r->n[0] & mask0) | (a->n[0] & mask1);
r->n[1] = (r->n[1] & mask0) | (a->n[1] & mask1);
r->n[2] = (r->n[2] & mask0) | (a->n[2] & mask1);
r->n[3] = (r->n[3] & mask0) | (a->n[3] & mask1);
r->n[4] = (r->n[4] & mask0) | (a->n[4] & mask1);
r->n[5] = (r->n[5] & mask0) | (a->n[5] & mask1);
r->n[6] = (r->n[6] & mask0) | (a->n[6] & mask1);
r->n[7] = (r->n[7] & mask0) | (a->n[7] & mask1);
r->n[8] = (r->n[8] & mask0) | (a->n[8] & mask1);
r->n[9] = (r->n[9] & mask0) | (a->n[9] & mask1);
#ifdef VERIFY
if (a->magnitude > r->magnitude) {
r->magnitude = a->magnitude;
}
r->normalized &= a->normalized;
#endif
}
static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage *r, const secp256k1_fe_storage *a, int flag) {
uint32_t mask0, mask1;
mask0 = flag + ~((uint32_t)0);
mask1 = ~mask0;
@ -1082,7 +1104,7 @@ static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r
r->n[7] = (r->n[7] & mask0) | (a->n[7] & mask1);
}
static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_to_storage(secp256k1_fe_storage *r, const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
#endif
@ -1096,7 +1118,7 @@ static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_f
r->n[7] = a->n[8] >> 16 | a->n[9] << 10;
}
static SECP256K1_INLINE void secp256k1_fe_from_storage(secp256k1_fe_t *r, const secp256k1_fe_storage_t *a) {
static SECP256K1_INLINE void secp256k1_fe_from_storage(secp256k1_fe *r, const secp256k1_fe_storage *a) {
r->n[0] = a->n[0] & 0x3FFFFFFUL;
r->n[1] = a->n[0] >> 26 | ((a->n[1] << 6) & 0x3FFFFFFUL);
r->n[2] = a->n[1] >> 20 | ((a->n[2] << 12) & 0x3FFFFFFUL);

@ -16,15 +16,15 @@ typedef struct {
int magnitude;
int normalized;
#endif
} secp256k1_fe_t;
} secp256k1_fe;
/* Unpacks a constant into a overlapping multi-limbed FE element. */
#define SECP256K1_FE_CONST_INNER(d7, d6, d5, d4, d3, d2, d1, d0) { \
(d0) | ((uint64_t)(d1) & 0xFFFFFUL) << 32, \
((d1) >> 20) | ((uint64_t)(d2)) << 12 | ((uint64_t)(d3) & 0xFFUL) << 44, \
((d3) >> 8) | ((uint64_t)(d4) & 0xFFFFFFFUL) << 24, \
((d4) >> 28) | ((uint64_t)(d5)) << 4 | ((uint64_t)(d6) & 0xFFFFUL) << 36, \
((d6) >> 16) | ((uint64_t)(d7)) << 16 \
(d0) | (((uint64_t)(d1) & 0xFFFFFUL) << 32), \
((uint64_t)(d1) >> 20) | (((uint64_t)(d2)) << 12) | (((uint64_t)(d3) & 0xFFUL) << 44), \
((uint64_t)(d3) >> 8) | (((uint64_t)(d4) & 0xFFFFFFFUL) << 24), \
((uint64_t)(d4) >> 28) | (((uint64_t)(d5)) << 4) | (((uint64_t)(d6) & 0xFFFFUL) << 36), \
((uint64_t)(d6) >> 16) | (((uint64_t)(d7)) << 16) \
}
#ifdef VERIFY
@ -35,13 +35,13 @@ typedef struct {
typedef struct {
uint64_t n[4];
} secp256k1_fe_storage_t;
} secp256k1_fe_storage;
#define SECP256K1_FE_STORAGE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{ \
(d0) | ((uint64_t)(d1)) << 32, \
(d2) | ((uint64_t)(d3)) << 32, \
(d4) | ((uint64_t)(d5)) << 32, \
(d6) | ((uint64_t)(d7)) << 32 \
(d0) | (((uint64_t)(d1)) << 32), \
(d2) | (((uint64_t)(d3)) << 32), \
(d4) | (((uint64_t)(d5)) << 32), \
(d6) | (((uint64_t)(d7)) << 32) \
}}
#endif

@ -31,7 +31,7 @@
*/
#ifdef VERIFY
static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
static void secp256k1_fe_verify(const secp256k1_fe *a) {
const uint64_t *d = a->n;
int m = a->normalized ? 1 : 2 * a->magnitude, r = 1;
/* secp256k1 'p' value defined in "Standards for Efficient Cryptography" (SEC2) 2.7.1. */
@ -51,12 +51,12 @@ static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
VERIFY_CHECK(r == 1);
}
#else
static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
static void secp256k1_fe_verify(const secp256k1_fe *a) {
(void)a;
}
#endif
static void secp256k1_fe_normalize(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize(secp256k1_fe *r) {
uint64_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4];
/* Reduce t4 at the start so there will be at most a single carry from the first pass */
@ -99,7 +99,7 @@ static void secp256k1_fe_normalize(secp256k1_fe_t *r) {
#endif
}
static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize_weak(secp256k1_fe *r) {
uint64_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4];
/* Reduce t4 at the start so there will be at most a single carry from the first pass */
@ -123,7 +123,7 @@ static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r) {
#endif
}
static void secp256k1_fe_normalize_var(secp256k1_fe_t *r) {
static void secp256k1_fe_normalize_var(secp256k1_fe *r) {
uint64_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4];
/* Reduce t4 at the start so there will be at most a single carry from the first pass */
@ -167,7 +167,7 @@ static void secp256k1_fe_normalize_var(secp256k1_fe_t *r) {
#endif
}
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
static int secp256k1_fe_normalizes_to_zero(secp256k1_fe *r) {
uint64_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4];
/* z0 tracks a possible raw value of 0, z1 tracks a possible raw value of P */
@ -190,7 +190,7 @@ static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
return (z0 == 0) | (z1 == 0xFFFFFFFFFFFFFULL);
}
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe *r) {
uint64_t t0, t1, t2, t3, t4;
uint64_t z0, z1;
uint64_t x;
@ -219,7 +219,7 @@ static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
t4 &= 0x0FFFFFFFFFFFFULL;
t1 += (t0 >> 52); t0 = z0;
t1 += (t0 >> 52);
t2 += (t1 >> 52); t1 &= 0xFFFFFFFFFFFFFULL; z0 |= t1; z1 &= t1;
t3 += (t2 >> 52); t2 &= 0xFFFFFFFFFFFFFULL; z0 |= t2; z1 &= t2;
t4 += (t3 >> 52); t3 &= 0xFFFFFFFFFFFFFULL; z0 |= t3; z1 &= t3;
@ -231,7 +231,7 @@ static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
return (z0 == 0) | (z1 == 0xFFFFFFFFFFFFFULL);
}
SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a) {
SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe *r, int a) {
r->n[0] = a;
r->n[1] = r->n[2] = r->n[3] = r->n[4] = 0;
#ifdef VERIFY
@ -241,7 +241,7 @@ SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a) {
#endif
}
SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe_t *a) {
SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe *a) {
const uint64_t *t = a->n;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -250,7 +250,7 @@ SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe_t *a) {
return (t[0] | t[1] | t[2] | t[3] | t[4]) == 0;
}
SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe_t *a) {
SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
secp256k1_fe_verify(a);
@ -258,7 +258,7 @@ SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe_t *a) {
return a->n[0] & 1;
}
SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe_t *a) {
SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe *a) {
int i;
#ifdef VERIFY
a->magnitude = 0;
@ -269,7 +269,7 @@ SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe_t *a) {
}
}
static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b) {
static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -288,7 +288,7 @@ static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b
return 0;
}
static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
static int secp256k1_fe_set_b32(secp256k1_fe *r, const unsigned char *a) {
int i;
r->n[0] = r->n[1] = r->n[2] = r->n[3] = r->n[4] = 0;
for (i=0; i<32; i++) {
@ -311,7 +311,7 @@ static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
}
/** Convert a field element to a 32-byte big endian value. Requires the input to be normalized */
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe *a) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
@ -329,7 +329,7 @@ static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a) {
}
}
SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp256k1_fe_t *a, int m) {
SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe *r, const secp256k1_fe *a, int m) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= m);
secp256k1_fe_verify(a);
@ -346,7 +346,7 @@ SECP256K1_INLINE static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp25
#endif
}
SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a) {
SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe *r, int a) {
r->n[0] *= a;
r->n[1] *= a;
r->n[2] *= a;
@ -359,7 +359,7 @@ SECP256K1_INLINE static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a) {
#endif
}
SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe *r, const secp256k1_fe *a) {
#ifdef VERIFY
secp256k1_fe_verify(a);
#endif
@ -375,7 +375,7 @@ SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1
#endif
}
static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const secp256k1_fe_t * SECP256K1_RESTRICT b) {
static void secp256k1_fe_mul(secp256k1_fe *r, const secp256k1_fe *a, const secp256k1_fe * SECP256K1_RESTRICT b) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= 8);
VERIFY_CHECK(b->magnitude <= 8);
@ -391,7 +391,7 @@ static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const s
#endif
}
static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_sqr(secp256k1_fe *r, const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->magnitude <= 8);
secp256k1_fe_verify(a);
@ -404,7 +404,24 @@ static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
#endif
}
static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r, const secp256k1_fe_storage_t *a, int flag) {
static SECP256K1_INLINE void secp256k1_fe_cmov(secp256k1_fe *r, const secp256k1_fe *a, int flag) {
uint64_t mask0, mask1;
mask0 = flag + ~((uint64_t)0);
mask1 = ~mask0;
r->n[0] = (r->n[0] & mask0) | (a->n[0] & mask1);
r->n[1] = (r->n[1] & mask0) | (a->n[1] & mask1);
r->n[2] = (r->n[2] & mask0) | (a->n[2] & mask1);
r->n[3] = (r->n[3] & mask0) | (a->n[3] & mask1);
r->n[4] = (r->n[4] & mask0) | (a->n[4] & mask1);
#ifdef VERIFY
if (a->magnitude > r->magnitude) {
r->magnitude = a->magnitude;
}
r->normalized &= a->normalized;
#endif
}
static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage *r, const secp256k1_fe_storage *a, int flag) {
uint64_t mask0, mask1;
mask0 = flag + ~((uint64_t)0);
mask1 = ~mask0;
@ -414,7 +431,7 @@ static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r
r->n[3] = (r->n[3] & mask0) | (a->n[3] & mask1);
}
static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_to_storage(secp256k1_fe_storage *r, const secp256k1_fe *a) {
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
#endif
@ -424,7 +441,7 @@ static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_f
r->n[3] = a->n[3] >> 36 | a->n[4] << 16;
}
static SECP256K1_INLINE void secp256k1_fe_from_storage(secp256k1_fe_t *r, const secp256k1_fe_storage_t *a) {
static SECP256K1_INLINE void secp256k1_fe_from_storage(secp256k1_fe *r, const secp256k1_fe_storage *a) {
r->n[0] = a->n[0] & 0xFFFFFFFFFFFFFULL;
r->n[1] = a->n[0] >> 52 | ((a->n[1] << 12) & 0xFFFFFFFFFFFFFULL);
r->n[2] = a->n[1] >> 40 | ((a->n[2] << 24) & 0xFFFFFFFFFFFFFULL);

@ -21,15 +21,15 @@
#error "Please select field implementation"
#endif
SECP256K1_INLINE static int secp256k1_fe_equal_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b) {
secp256k1_fe_t na;
SECP256K1_INLINE static int secp256k1_fe_equal_var(const secp256k1_fe *a, const secp256k1_fe *b) {
secp256k1_fe na;
secp256k1_fe_negate(&na, a, 1);
secp256k1_fe_add(&na, b);
return secp256k1_fe_normalizes_to_zero_var(&na);
}
static int secp256k1_fe_sqrt_var(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
secp256k1_fe_t x2, x3, x6, x9, x11, x22, x44, x88, x176, x220, x223, t1;
static int secp256k1_fe_sqrt_var(secp256k1_fe *r, const secp256k1_fe *a) {
secp256k1_fe x2, x3, x6, x9, x11, x22, x44, x88, x176, x220, x223, t1;
int j;
/** The binary representation of (p + 1)/4 has 3 blocks of 1s, with lengths in
@ -117,8 +117,8 @@ static int secp256k1_fe_sqrt_var(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
return secp256k1_fe_equal_var(&t1, a);
}
static void secp256k1_fe_inv(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
secp256k1_fe_t x2, x3, x6, x9, x11, x22, x44, x88, x176, x220, x223, t1;
static void secp256k1_fe_inv(secp256k1_fe *r, const secp256k1_fe *a) {
secp256k1_fe x2, x3, x6, x9, x11, x22, x44, x88, x176, x220, x223, t1;
int j;
/** The binary representation of (p - 2) has 5 blocks of 1s, with lengths in
@ -207,11 +207,15 @@ static void secp256k1_fe_inv(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
secp256k1_fe_mul(r, a, &t1);
}
static void secp256k1_fe_inv_var(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
static void secp256k1_fe_inv_var(secp256k1_fe *r, const secp256k1_fe *a) {
#if defined(USE_FIELD_INV_BUILTIN)
secp256k1_fe_inv(r, a);
#elif defined(USE_FIELD_INV_NUM)
secp256k1_num_t n, m;
secp256k1_num n, m;
static const secp256k1_fe negone = SECP256K1_FE_CONST(
0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFFUL,
0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFEUL, 0xFFFFFC2EUL
);
/* secp256k1 field prime, value p defined in "Standards for Efficient Cryptography" (SEC2) 2.7.1. */
static const unsigned char prime[32] = {
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
@ -220,7 +224,7 @@ static void secp256k1_fe_inv_var(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
0xFF,0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F
};
unsigned char b[32];
secp256k1_fe_t c = *a;
secp256k1_fe c = *a;
secp256k1_fe_normalize_var(&c);
secp256k1_fe_get_b32(b, &c);
secp256k1_num_set_bin(&n, b, 32);
@ -228,13 +232,17 @@ static void secp256k1_fe_inv_var(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
secp256k1_num_mod_inverse(&n, &n, &m);
secp256k1_num_get_bin(b, 32, &n);
VERIFY_CHECK(secp256k1_fe_set_b32(r, b));
/* Verify the result is the (unique) valid inverse using non-GMP code. */
secp256k1_fe_mul(&c, &c, r);
secp256k1_fe_add(&c, &negone);
CHECK(secp256k1_fe_normalizes_to_zero_var(&c));
#else
#error "Please select field inverse implementation"
#endif
}
static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe_t *r, const secp256k1_fe_t *a) {
secp256k1_fe_t u;
static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe *r, const secp256k1_fe *a) {
secp256k1_fe u;
size_t i;
if (len < 1) {
return;
@ -252,7 +260,7 @@ static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe_t *r, const secp25
secp256k1_fe_inv_var(&u, &r[--i]);
while (i > 0) {
int j = i--;
size_t j = i--;
secp256k1_fe_mul(&r[j], &r[i], &u);
secp256k1_fe_mul(&u, &u, &a[j]);
}

@ -0,0 +1,74 @@
/**********************************************************************
* Copyright (c) 2013, 2014, 2015 Thomas Daede, Cory Fields *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#define USE_BASIC_CONFIG 1
#include "basic-config.h"
#include "include/secp256k1.h"
#include "field_impl.h"
#include "scalar_impl.h"
#include "group_impl.h"
#include "ecmult_gen_impl.h"
static void default_error_callback_fn(const char* str, void* data) {
(void)data;
fprintf(stderr, "[libsecp256k1] internal consistency check failed: %s\n", str);
abort();
}
static const secp256k1_callback default_error_callback = {
default_error_callback_fn,
NULL
};
int main(int argc, char **argv) {
secp256k1_ecmult_gen_context ctx;
int inner;
int outer;
FILE* fp;
(void)argc;
(void)argv;
fp = fopen("src/ecmult_static_context.h","w");
if (fp == NULL) {
fprintf(stderr, "Could not open src/ecmult_static_context.h for writing!\n");
return -1;
}
fprintf(fp, "#ifndef _SECP256K1_ECMULT_STATIC_CONTEXT_\n");
fprintf(fp, "#define _SECP256K1_ECMULT_STATIC_CONTEXT_\n");
fprintf(fp, "#include \"group.h\"\n");
fprintf(fp, "#define SC SECP256K1_GE_STORAGE_CONST\n");
fprintf(fp, "static const secp256k1_ge_storage secp256k1_ecmult_static_context[64][16] = {\n");
secp256k1_ecmult_gen_context_init(&ctx);
secp256k1_ecmult_gen_context_build(&ctx, &default_error_callback);
for(outer = 0; outer != 64; outer++) {
fprintf(fp,"{\n");
for(inner = 0; inner != 16; inner++) {
fprintf(fp," SC(%uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu, %uu)", SECP256K1_GE_STORAGE_CONST_GET((*ctx.prec)[outer][inner]));
if (inner != 15) {
fprintf(fp,",\n");
} else {
fprintf(fp,"\n");
}
}
if (outer != 63) {
fprintf(fp,"},\n");
} else {
fprintf(fp,"}\n");
}
}
fprintf(fp,"};\n");
secp256k1_ecmult_gen_context_clear(&ctx);
fprintf(fp, "#undef SC\n");
fprintf(fp, "#endif\n");
fclose(fp);
return 0;
}

@ -0,0 +1,141 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_GROUP_
#define _SECP256K1_GROUP_
#include "num.h"
#include "field.h"
/** A group element of the secp256k1 curve, in affine coordinates. */
typedef struct {
secp256k1_fe x;
secp256k1_fe y;
int infinity; /* whether this represents the point at infinity */
} secp256k1_ge;
#define SECP256K1_GE_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_CONST((i),(j),(k),(l),(m),(n),(o),(p)), 0}
#define SECP256K1_GE_CONST_INFINITY {SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), 1}
/** A group element of the secp256k1 curve, in jacobian coordinates. */
typedef struct {
secp256k1_fe x; /* actual X: x/z^2 */
secp256k1_fe y; /* actual Y: y/z^3 */
secp256k1_fe z;
int infinity; /* whether this represents the point at infinity */
} secp256k1_gej;
#define SECP256K1_GEJ_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_CONST((i),(j),(k),(l),(m),(n),(o),(p)), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 1), 0}
#define SECP256K1_GEJ_CONST_INFINITY {SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), 1}
typedef struct {
secp256k1_fe_storage x;
secp256k1_fe_storage y;
} secp256k1_ge_storage;
#define SECP256K1_GE_STORAGE_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_STORAGE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_STORAGE_CONST((i),(j),(k),(l),(m),(n),(o),(p))}
#define SECP256K1_GE_STORAGE_CONST_GET(t) SECP256K1_FE_STORAGE_CONST_GET(t.x), SECP256K1_FE_STORAGE_CONST_GET(t.y)
/** Set a group element equal to the point at infinity */
static void secp256k1_ge_set_infinity(secp256k1_ge *r);
/** Set a group element equal to the point with given X and Y coordinates */
static void secp256k1_ge_set_xy(secp256k1_ge *r, const secp256k1_fe *x, const secp256k1_fe *y);
/** Set a group element (affine) equal to the point with the given X coordinate, and given oddness
* for Y. Return value indicates whether the result is valid. */
static int secp256k1_ge_set_xo_var(secp256k1_ge *r, const secp256k1_fe *x, int odd);
/** Check whether a group element is the point at infinity. */
static int secp256k1_ge_is_infinity(const secp256k1_ge *a);
/** Check whether a group element is valid (i.e., on the curve). */
static int secp256k1_ge_is_valid_var(const secp256k1_ge *a);
static void secp256k1_ge_neg(secp256k1_ge *r, const secp256k1_ge *a);
/** Set a group element equal to another which is given in jacobian coordinates */
static void secp256k1_ge_set_gej(secp256k1_ge *r, secp256k1_gej *a);
/** Set a batch of group elements equal to the inputs given in jacobian coordinates */
static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_callback *cb);
/** Set a batch of group elements equal to the inputs given in jacobian
* coordinates (with known z-ratios). zr must contain the known z-ratios such
* that mul(a[i].z, zr[i+1]) == a[i+1].z. zr[0] is ignored. */
static void secp256k1_ge_set_table_gej_var(size_t len, secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_fe *zr);
/** Bring a batch inputs given in jacobian coordinates (with known z-ratios) to
* the same global z "denominator". zr must contain the known z-ratios such
* that mul(a[i].z, zr[i+1]) == a[i+1].z. zr[0] is ignored. The x and y
* coordinates of the result are stored in r, the common z coordinate is
* stored in globalz. */
static void secp256k1_ge_globalz_set_table_gej(size_t len, secp256k1_ge *r, secp256k1_fe *globalz, const secp256k1_gej *a, const secp256k1_fe *zr);
/** Set a group element (jacobian) equal to the point at infinity. */
static void secp256k1_gej_set_infinity(secp256k1_gej *r);
/** Set a group element (jacobian) equal to the point with given X and Y coordinates. */
static void secp256k1_gej_set_xy(secp256k1_gej *r, const secp256k1_fe *x, const secp256k1_fe *y);
/** Set a group element (jacobian) equal to another which is given in affine coordinates. */
static void secp256k1_gej_set_ge(secp256k1_gej *r, const secp256k1_ge *a);
/** Compare the X coordinate of a group element (jacobian). */
static int secp256k1_gej_eq_x_var(const secp256k1_fe *x, const secp256k1_gej *a);
/** Set r equal to the inverse of a (i.e., mirrored around the X axis) */
static void secp256k1_gej_neg(secp256k1_gej *r, const secp256k1_gej *a);
/** Check whether a group element is the point at infinity. */
static int secp256k1_gej_is_infinity(const secp256k1_gej *a);
/** Set r equal to the double of a. If rzr is not-NULL, r->z = a->z * *rzr (where infinity means an implicit z = 0).
* a may not be zero. Constant time. */
static void secp256k1_gej_double_nonzero(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr);
/** Set r equal to the double of a. If rzr is not-NULL, r->z = a->z * *rzr (where infinity means an implicit z = 0). */
static void secp256k1_gej_double_var(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr);
/** Set r equal to the sum of a and b. If rzr is non-NULL, r->z = a->z * *rzr (a cannot be infinity in that case). */
static void secp256k1_gej_add_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_gej *b, secp256k1_fe *rzr);
/** Set r equal to the sum of a and b (with b given in affine coordinates, and not infinity). */
static void secp256k1_gej_add_ge(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b);
/** Set r equal to the sum of a and b (with b given in affine coordinates). This is more efficient
than secp256k1_gej_add_var. It is identical to secp256k1_gej_add_ge but without constant-time
guarantee, and b is allowed to be infinity. If rzr is non-NULL, r->z = a->z * *rzr (a cannot be infinity in that case). */
static void secp256k1_gej_add_ge_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b, secp256k1_fe *rzr);
/** Set r equal to the sum of a and b (with the inverse of b's Z coordinate passed as bzinv). */
static void secp256k1_gej_add_zinv_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b, const secp256k1_fe *bzinv);
#ifdef USE_ENDOMORPHISM
/** Set r to be equal to lambda times a, where lambda is chosen in a way such that this is very fast. */
static void secp256k1_ge_mul_lambda(secp256k1_ge *r, const secp256k1_ge *a);
#endif
/** Clear a secp256k1_gej to prevent leaking sensitive information. */
static void secp256k1_gej_clear(secp256k1_gej *r);
/** Clear a secp256k1_ge to prevent leaking sensitive information. */
static void secp256k1_ge_clear(secp256k1_ge *r);
/** Convert a group element to the storage type. */
static void secp256k1_ge_to_storage(secp256k1_ge_storage *r, const secp256k1_ge *a);
/** Convert a group element back from the storage type. */
static void secp256k1_ge_from_storage(secp256k1_ge *r, const secp256k1_ge_storage *a);
/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */
static void secp256k1_ge_storage_cmov(secp256k1_ge_storage *r, const secp256k1_ge_storage *a, int flag);
/** Rescale a jacobian point by b which must be non-zero. Constant-time. */
static void secp256k1_gej_rescale(secp256k1_gej *r, const secp256k1_fe *b);
#endif

@ -0,0 +1,632 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_GROUP_IMPL_H_
#define _SECP256K1_GROUP_IMPL_H_
#include <string.h>
#include "num.h"
#include "field.h"
#include "group.h"
/** Generator for secp256k1, value 'g' defined in
* "Standards for Efficient Cryptography" (SEC2) 2.7.1.
*/
static const secp256k1_ge secp256k1_ge_const_g = SECP256K1_GE_CONST(
0x79BE667EUL, 0xF9DCBBACUL, 0x55A06295UL, 0xCE870B07UL,
0x029BFCDBUL, 0x2DCE28D9UL, 0x59F2815BUL, 0x16F81798UL,
0x483ADA77UL, 0x26A3C465UL, 0x5DA4FBFCUL, 0x0E1108A8UL,
0xFD17B448UL, 0xA6855419UL, 0x9C47D08FUL, 0xFB10D4B8UL
);
static void secp256k1_ge_set_gej_zinv(secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_fe *zi) {
secp256k1_fe zi2;
secp256k1_fe zi3;
secp256k1_fe_sqr(&zi2, zi);
secp256k1_fe_mul(&zi3, &zi2, zi);
secp256k1_fe_mul(&r->x, &a->x, &zi2);
secp256k1_fe_mul(&r->y, &a->y, &zi3);
r->infinity = a->infinity;
}
static void secp256k1_ge_set_infinity(secp256k1_ge *r) {
r->infinity = 1;
}
static void secp256k1_ge_set_xy(secp256k1_ge *r, const secp256k1_fe *x, const secp256k1_fe *y) {
r->infinity = 0;
r->x = *x;
r->y = *y;
}
static int secp256k1_ge_is_infinity(const secp256k1_ge *a) {
return a->infinity;
}
static void secp256k1_ge_neg(secp256k1_ge *r, const secp256k1_ge *a) {
*r = *a;
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
static void secp256k1_ge_set_gej(secp256k1_ge *r, secp256k1_gej *a) {
secp256k1_fe z2, z3;
r->infinity = a->infinity;
secp256k1_fe_inv(&a->z, &a->z);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_mul(&z3, &a->z, &z2);
secp256k1_fe_mul(&a->x, &a->x, &z2);
secp256k1_fe_mul(&a->y, &a->y, &z3);
secp256k1_fe_set_int(&a->z, 1);
r->x = a->x;
r->y = a->y;
}
static void secp256k1_ge_set_gej_var(secp256k1_ge *r, secp256k1_gej *a) {
secp256k1_fe z2, z3;
r->infinity = a->infinity;
if (a->infinity) {
return;
}
secp256k1_fe_inv_var(&a->z, &a->z);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_mul(&z3, &a->z, &z2);
secp256k1_fe_mul(&a->x, &a->x, &z2);
secp256k1_fe_mul(&a->y, &a->y, &z3);
secp256k1_fe_set_int(&a->z, 1);
r->x = a->x;
r->y = a->y;
}
static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_callback *cb) {
secp256k1_fe *az;
secp256k1_fe *azi;
size_t i;
size_t count = 0;
az = (secp256k1_fe *)checked_malloc(cb, sizeof(secp256k1_fe) * len);
for (i = 0; i < len; i++) {
if (!a[i].infinity) {
az[count++] = a[i].z;
}
}
azi = (secp256k1_fe *)checked_malloc(cb, sizeof(secp256k1_fe) * count);
secp256k1_fe_inv_all_var(count, azi, az);
free(az);
count = 0;
for (i = 0; i < len; i++) {
r[i].infinity = a[i].infinity;
if (!a[i].infinity) {
secp256k1_ge_set_gej_zinv(&r[i], &a[i], &azi[count++]);
}
}
free(azi);
}
static void secp256k1_ge_set_table_gej_var(size_t len, secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_fe *zr) {
size_t i = len - 1;
secp256k1_fe zi;
if (len > 0) {
/* Compute the inverse of the last z coordinate, and use it to compute the last affine output. */
secp256k1_fe_inv(&zi, &a[i].z);
secp256k1_ge_set_gej_zinv(&r[i], &a[i], &zi);
/* Work out way backwards, using the z-ratios to scale the x/y values. */
while (i > 0) {
secp256k1_fe_mul(&zi, &zi, &zr[i]);
i--;
secp256k1_ge_set_gej_zinv(&r[i], &a[i], &zi);
}
}
}
static void secp256k1_ge_globalz_set_table_gej(size_t len, secp256k1_ge *r, secp256k1_fe *globalz, const secp256k1_gej *a, const secp256k1_fe *zr) {
size_t i = len - 1;
secp256k1_fe zs;
if (len > 0) {
/* The z of the final point gives us the "global Z" for the table. */
r[i].x = a[i].x;
r[i].y = a[i].y;
*globalz = a[i].z;
r[i].infinity = 0;
zs = zr[i];
/* Work our way backwards, using the z-ratios to scale the x/y values. */
while (i > 0) {
if (i != len - 1) {
secp256k1_fe_mul(&zs, &zs, &zr[i]);
}
i--;
secp256k1_ge_set_gej_zinv(&r[i], &a[i], &zs);
}
}
}
static void secp256k1_gej_set_infinity(secp256k1_gej *r) {
r->infinity = 1;
secp256k1_fe_set_int(&r->x, 0);
secp256k1_fe_set_int(&r->y, 0);
secp256k1_fe_set_int(&r->z, 0);
}
static void secp256k1_gej_set_xy(secp256k1_gej *r, const secp256k1_fe *x, const secp256k1_fe *y) {
r->infinity = 0;
r->x = *x;
r->y = *y;
secp256k1_fe_set_int(&r->z, 1);
}
static void secp256k1_gej_clear(secp256k1_gej *r) {
r->infinity = 0;
secp256k1_fe_clear(&r->x);
secp256k1_fe_clear(&r->y);
secp256k1_fe_clear(&r->z);
}
static void secp256k1_ge_clear(secp256k1_ge *r) {
r->infinity = 0;
secp256k1_fe_clear(&r->x);
secp256k1_fe_clear(&r->y);
}
static int secp256k1_ge_set_xo_var(secp256k1_ge *r, const secp256k1_fe *x, int odd) {
secp256k1_fe x2, x3, c;
r->x = *x;
secp256k1_fe_sqr(&x2, x);
secp256k1_fe_mul(&x3, x, &x2);
r->infinity = 0;
secp256k1_fe_set_int(&c, 7);
secp256k1_fe_add(&c, &x3);
if (!secp256k1_fe_sqrt_var(&r->y, &c)) {
return 0;
}
secp256k1_fe_normalize_var(&r->y);
if (secp256k1_fe_is_odd(&r->y) != odd) {
secp256k1_fe_negate(&r->y, &r->y, 1);
}
return 1;
}
static void secp256k1_gej_set_ge(secp256k1_gej *r, const secp256k1_ge *a) {
r->infinity = a->infinity;
r->x = a->x;
r->y = a->y;
secp256k1_fe_set_int(&r->z, 1);
}
static int secp256k1_gej_eq_x_var(const secp256k1_fe *x, const secp256k1_gej *a) {
secp256k1_fe r, r2;
VERIFY_CHECK(!a->infinity);
secp256k1_fe_sqr(&r, &a->z); secp256k1_fe_mul(&r, &r, x);
r2 = a->x; secp256k1_fe_normalize_weak(&r2);
return secp256k1_fe_equal_var(&r, &r2);
}
static void secp256k1_gej_neg(secp256k1_gej *r, const secp256k1_gej *a) {
r->infinity = a->infinity;
r->x = a->x;
r->y = a->y;
r->z = a->z;
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
static int secp256k1_gej_is_infinity(const secp256k1_gej *a) {
return a->infinity;
}
static int secp256k1_gej_is_valid_var(const secp256k1_gej *a) {
secp256k1_fe y2, x3, z2, z6;
if (a->infinity) {
return 0;
}
/** y^2 = x^3 + 7
* (Y/Z^3)^2 = (X/Z^2)^3 + 7
* Y^2 / Z^6 = X^3 / Z^6 + 7
* Y^2 = X^3 + 7*Z^6
*/
secp256k1_fe_sqr(&y2, &a->y);
secp256k1_fe_sqr(&x3, &a->x); secp256k1_fe_mul(&x3, &x3, &a->x);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_sqr(&z6, &z2); secp256k1_fe_mul(&z6, &z6, &z2);
secp256k1_fe_mul_int(&z6, 7);
secp256k1_fe_add(&x3, &z6);
secp256k1_fe_normalize_weak(&x3);
return secp256k1_fe_equal_var(&y2, &x3);
}
static int secp256k1_ge_is_valid_var(const secp256k1_ge *a) {
secp256k1_fe y2, x3, c;
if (a->infinity) {
return 0;
}
/* y^2 = x^3 + 7 */
secp256k1_fe_sqr(&y2, &a->y);
secp256k1_fe_sqr(&x3, &a->x); secp256k1_fe_mul(&x3, &x3, &a->x);
secp256k1_fe_set_int(&c, 7);
secp256k1_fe_add(&x3, &c);
secp256k1_fe_normalize_weak(&x3);
return secp256k1_fe_equal_var(&y2, &x3);
}
static void secp256k1_gej_double_var(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr) {
/* Operations: 3 mul, 4 sqr, 0 normalize, 12 mul_int/add/negate */
secp256k1_fe t1,t2,t3,t4;
/** For secp256k1, 2Q is infinity if and only if Q is infinity. This is because if 2Q = infinity,
* Q must equal -Q, or that Q.y == -(Q.y), or Q.y is 0. For a point on y^2 = x^3 + 7 to have
* y=0, x^3 must be -7 mod p. However, -7 has no cube root mod p.
*/
r->infinity = a->infinity;
if (r->infinity) {
if (rzr != NULL) {
secp256k1_fe_set_int(rzr, 1);
}
return;
}
if (rzr != NULL) {
*rzr = a->y;
secp256k1_fe_normalize_weak(rzr);
secp256k1_fe_mul_int(rzr, 2);
}
secp256k1_fe_mul(&r->z, &a->z, &a->y);
secp256k1_fe_mul_int(&r->z, 2); /* Z' = 2*Y*Z (2) */
secp256k1_fe_sqr(&t1, &a->x);
secp256k1_fe_mul_int(&t1, 3); /* T1 = 3*X^2 (3) */
secp256k1_fe_sqr(&t2, &t1); /* T2 = 9*X^4 (1) */
secp256k1_fe_sqr(&t3, &a->y);
secp256k1_fe_mul_int(&t3, 2); /* T3 = 2*Y^2 (2) */
secp256k1_fe_sqr(&t4, &t3);
secp256k1_fe_mul_int(&t4, 2); /* T4 = 8*Y^4 (2) */
secp256k1_fe_mul(&t3, &t3, &a->x); /* T3 = 2*X*Y^2 (1) */
r->x = t3;
secp256k1_fe_mul_int(&r->x, 4); /* X' = 8*X*Y^2 (4) */
secp256k1_fe_negate(&r->x, &r->x, 4); /* X' = -8*X*Y^2 (5) */
secp256k1_fe_add(&r->x, &t2); /* X' = 9*X^4 - 8*X*Y^2 (6) */
secp256k1_fe_negate(&t2, &t2, 1); /* T2 = -9*X^4 (2) */
secp256k1_fe_mul_int(&t3, 6); /* T3 = 12*X*Y^2 (6) */
secp256k1_fe_add(&t3, &t2); /* T3 = 12*X*Y^2 - 9*X^4 (8) */
secp256k1_fe_mul(&r->y, &t1, &t3); /* Y' = 36*X^3*Y^2 - 27*X^6 (1) */
secp256k1_fe_negate(&t2, &t4, 2); /* T2 = -8*Y^4 (3) */
secp256k1_fe_add(&r->y, &t2); /* Y' = 36*X^3*Y^2 - 27*X^6 - 8*Y^4 (4) */
}
static SECP256K1_INLINE void secp256k1_gej_double_nonzero(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr) {
VERIFY_CHECK(!secp256k1_gej_is_infinity(a));
secp256k1_gej_double_var(r, a, rzr);
}
static void secp256k1_gej_add_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_gej *b, secp256k1_fe *rzr) {
/* Operations: 12 mul, 4 sqr, 2 normalize, 12 mul_int/add/negate */
secp256k1_fe z22, z12, u1, u2, s1, s2, h, i, i2, h2, h3, t;
if (a->infinity) {
VERIFY_CHECK(rzr == NULL);
*r = *b;
return;
}
if (b->infinity) {
if (rzr != NULL) {
secp256k1_fe_set_int(rzr, 1);
}
*r = *a;
return;
}
r->infinity = 0;
secp256k1_fe_sqr(&z22, &b->z);
secp256k1_fe_sqr(&z12, &a->z);
secp256k1_fe_mul(&u1, &a->x, &z22);
secp256k1_fe_mul(&u2, &b->x, &z12);
secp256k1_fe_mul(&s1, &a->y, &z22); secp256k1_fe_mul(&s1, &s1, &b->z);
secp256k1_fe_mul(&s2, &b->y, &z12); secp256k1_fe_mul(&s2, &s2, &a->z);
secp256k1_fe_negate(&h, &u1, 1); secp256k1_fe_add(&h, &u2);
secp256k1_fe_negate(&i, &s1, 1); secp256k1_fe_add(&i, &s2);
if (secp256k1_fe_normalizes_to_zero_var(&h)) {
if (secp256k1_fe_normalizes_to_zero_var(&i)) {
secp256k1_gej_double_var(r, a, rzr);
} else {
if (rzr != NULL) {
secp256k1_fe_set_int(rzr, 0);
}
r->infinity = 1;
}
return;
}
secp256k1_fe_sqr(&i2, &i);
secp256k1_fe_sqr(&h2, &h);
secp256k1_fe_mul(&h3, &h, &h2);
secp256k1_fe_mul(&h, &h, &b->z);
if (rzr != NULL) {
*rzr = h;
}
secp256k1_fe_mul(&r->z, &a->z, &h);
secp256k1_fe_mul(&t, &u1, &h2);
r->x = t; secp256k1_fe_mul_int(&r->x, 2); secp256k1_fe_add(&r->x, &h3); secp256k1_fe_negate(&r->x, &r->x, 3); secp256k1_fe_add(&r->x, &i2);
secp256k1_fe_negate(&r->y, &r->x, 5); secp256k1_fe_add(&r->y, &t); secp256k1_fe_mul(&r->y, &r->y, &i);
secp256k1_fe_mul(&h3, &h3, &s1); secp256k1_fe_negate(&h3, &h3, 1);
secp256k1_fe_add(&r->y, &h3);
}
static void secp256k1_gej_add_ge_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b, secp256k1_fe *rzr) {
/* 8 mul, 3 sqr, 4 normalize, 12 mul_int/add/negate */
secp256k1_fe z12, u1, u2, s1, s2, h, i, i2, h2, h3, t;
if (a->infinity) {
VERIFY_CHECK(rzr == NULL);
secp256k1_gej_set_ge(r, b);
return;
}
if (b->infinity) {
if (rzr != NULL) {
secp256k1_fe_set_int(rzr, 1);
}
*r = *a;
return;
}
r->infinity = 0;
secp256k1_fe_sqr(&z12, &a->z);
u1 = a->x; secp256k1_fe_normalize_weak(&u1);
secp256k1_fe_mul(&u2, &b->x, &z12);
s1 = a->y; secp256k1_fe_normalize_weak(&s1);
secp256k1_fe_mul(&s2, &b->y, &z12); secp256k1_fe_mul(&s2, &s2, &a->z);
secp256k1_fe_negate(&h, &u1, 1); secp256k1_fe_add(&h, &u2);
secp256k1_fe_negate(&i, &s1, 1); secp256k1_fe_add(&i, &s2);
if (secp256k1_fe_normalizes_to_zero_var(&h)) {
if (secp256k1_fe_normalizes_to_zero_var(&i)) {
secp256k1_gej_double_var(r, a, rzr);
} else {
if (rzr != NULL) {
secp256k1_fe_set_int(rzr, 0);
}
r->infinity = 1;
}
return;
}
secp256k1_fe_sqr(&i2, &i);
secp256k1_fe_sqr(&h2, &h);
secp256k1_fe_mul(&h3, &h, &h2);
if (rzr != NULL) {
*rzr = h;
}
secp256k1_fe_mul(&r->z, &a->z, &h);
secp256k1_fe_mul(&t, &u1, &h2);
r->x = t; secp256k1_fe_mul_int(&r->x, 2); secp256k1_fe_add(&r->x, &h3); secp256k1_fe_negate(&r->x, &r->x, 3); secp256k1_fe_add(&r->x, &i2);
secp256k1_fe_negate(&r->y, &r->x, 5); secp256k1_fe_add(&r->y, &t); secp256k1_fe_mul(&r->y, &r->y, &i);
secp256k1_fe_mul(&h3, &h3, &s1); secp256k1_fe_negate(&h3, &h3, 1);
secp256k1_fe_add(&r->y, &h3);
}
static void secp256k1_gej_add_zinv_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b, const secp256k1_fe *bzinv) {
/* 9 mul, 3 sqr, 4 normalize, 12 mul_int/add/negate */
secp256k1_fe az, z12, u1, u2, s1, s2, h, i, i2, h2, h3, t;
if (b->infinity) {
*r = *a;
return;
}
if (a->infinity) {
secp256k1_fe bzinv2, bzinv3;
r->infinity = b->infinity;
secp256k1_fe_sqr(&bzinv2, bzinv);
secp256k1_fe_mul(&bzinv3, &bzinv2, bzinv);
secp256k1_fe_mul(&r->x, &b->x, &bzinv2);
secp256k1_fe_mul(&r->y, &b->y, &bzinv3);
secp256k1_fe_set_int(&r->z, 1);
return;
}
r->infinity = 0;
/** We need to calculate (rx,ry,rz) = (ax,ay,az) + (bx,by,1/bzinv). Due to
* secp256k1's isomorphism we can multiply the Z coordinates on both sides
* by bzinv, and get: (rx,ry,rz*bzinv) = (ax,ay,az*bzinv) + (bx,by,1).
* This means that (rx,ry,rz) can be calculated as
* (ax,ay,az*bzinv) + (bx,by,1), when not applying the bzinv factor to rz.
* The variable az below holds the modified Z coordinate for a, which is used
* for the computation of rx and ry, but not for rz.
*/
secp256k1_fe_mul(&az, &a->z, bzinv);
secp256k1_fe_sqr(&z12, &az);
u1 = a->x; secp256k1_fe_normalize_weak(&u1);
secp256k1_fe_mul(&u2, &b->x, &z12);
s1 = a->y; secp256k1_fe_normalize_weak(&s1);
secp256k1_fe_mul(&s2, &b->y, &z12); secp256k1_fe_mul(&s2, &s2, &az);
secp256k1_fe_negate(&h, &u1, 1); secp256k1_fe_add(&h, &u2);
secp256k1_fe_negate(&i, &s1, 1); secp256k1_fe_add(&i, &s2);
if (secp256k1_fe_normalizes_to_zero_var(&h)) {
if (secp256k1_fe_normalizes_to_zero_var(&i)) {
secp256k1_gej_double_var(r, a, NULL);
} else {
r->infinity = 1;
}
return;
}
secp256k1_fe_sqr(&i2, &i);
secp256k1_fe_sqr(&h2, &h);
secp256k1_fe_mul(&h3, &h, &h2);
r->z = a->z; secp256k1_fe_mul(&r->z, &r->z, &h);
secp256k1_fe_mul(&t, &u1, &h2);
r->x = t; secp256k1_fe_mul_int(&r->x, 2); secp256k1_fe_add(&r->x, &h3); secp256k1_fe_negate(&r->x, &r->x, 3); secp256k1_fe_add(&r->x, &i2);
secp256k1_fe_negate(&r->y, &r->x, 5); secp256k1_fe_add(&r->y, &t); secp256k1_fe_mul(&r->y, &r->y, &i);
secp256k1_fe_mul(&h3, &h3, &s1); secp256k1_fe_negate(&h3, &h3, 1);
secp256k1_fe_add(&r->y, &h3);
}
static void secp256k1_gej_add_ge(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b) {
/* Operations: 7 mul, 5 sqr, 4 normalize, 21 mul_int/add/negate/cmov */
static const secp256k1_fe fe_1 = SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 1);
secp256k1_fe zz, u1, u2, s1, s2, t, tt, m, n, q, rr;
secp256k1_fe m_alt, rr_alt;
int infinity, degenerate;
VERIFY_CHECK(!b->infinity);
VERIFY_CHECK(a->infinity == 0 || a->infinity == 1);
/** In:
* Eric Brier and Marc Joye, Weierstrass Elliptic Curves and Side-Channel Attacks.
* In D. Naccache and P. Paillier, Eds., Public Key Cryptography, vol. 2274 of Lecture Notes in Computer Science, pages 335-345. Springer-Verlag, 2002.
* we find as solution for a unified addition/doubling formula:
* lambda = ((x1 + x2)^2 - x1 * x2 + a) / (y1 + y2), with a = 0 for secp256k1's curve equation.
* x3 = lambda^2 - (x1 + x2)
* 2*y3 = lambda * (x1 + x2 - 2 * x3) - (y1 + y2).
*
* Substituting x_i = Xi / Zi^2 and yi = Yi / Zi^3, for i=1,2,3, gives:
* U1 = X1*Z2^2, U2 = X2*Z1^2
* S1 = Y1*Z2^3, S2 = Y2*Z1^3
* Z = Z1*Z2
* T = U1+U2
* M = S1+S2
* Q = T*M^2
* R = T^2-U1*U2
* X3 = 4*(R^2-Q)
* Y3 = 4*(R*(3*Q-2*R^2)-M^4)
* Z3 = 2*M*Z
* (Note that the paper uses xi = Xi / Zi and yi = Yi / Zi instead.)
*
* This formula has the benefit of being the same for both addition
* of distinct points and doubling. However, it breaks down in the
* case that either point is infinity, or that y1 = -y2. We handle
* these cases in the following ways:
*
* - If b is infinity we simply bail by means of a VERIFY_CHECK.
*
* - If a is infinity, we detect this, and at the end of the
* computation replace the result (which will be meaningless,
* but we compute to be constant-time) with b.x : b.y : 1.
*
* - If a = -b, we have y1 = -y2, which is a degenerate case.
* But here the answer is infinity, so we simply set the
* infinity flag of the result, overriding the computed values
* without even needing to cmov.
*
* - If y1 = -y2 but x1 != x2, which does occur thanks to certain
* properties of our curve (specifically, 1 has nontrivial cube
* roots in our field, and the curve equation has no x coefficient)
* then the answer is not infinity but also not given by the above
* equation. In this case, we cmov in place an alternate expression
* for lambda. Specifically (y1 - y2)/(x1 - x2). Where both these
* expressions for lambda are defined, they are equal, and can be
* obtained from each other by multiplication by (y1 + y2)/(y1 + y2)
* then substitution of x^3 + 7 for y^2 (using the curve equation).
* For all pairs of nonzero points (a, b) at least one is defined,
* so this covers everything.
*/
secp256k1_fe_sqr(&zz, &a->z); /* z = Z1^2 */
u1 = a->x; secp256k1_fe_normalize_weak(&u1); /* u1 = U1 = X1*Z2^2 (1) */
secp256k1_fe_mul(&u2, &b->x, &zz); /* u2 = U2 = X2*Z1^2 (1) */
s1 = a->y; secp256k1_fe_normalize_weak(&s1); /* s1 = S1 = Y1*Z2^3 (1) */
secp256k1_fe_mul(&s2, &b->y, &zz); /* s2 = Y2*Z1^2 (1) */
secp256k1_fe_mul(&s2, &s2, &a->z); /* s2 = S2 = Y2*Z1^3 (1) */
t = u1; secp256k1_fe_add(&t, &u2); /* t = T = U1+U2 (2) */
m = s1; secp256k1_fe_add(&m, &s2); /* m = M = S1+S2 (2) */
secp256k1_fe_sqr(&rr, &t); /* rr = T^2 (1) */
secp256k1_fe_negate(&m_alt, &u2, 1); /* Malt = -X2*Z1^2 */
secp256k1_fe_mul(&tt, &u1, &m_alt); /* tt = -U1*U2 (2) */
secp256k1_fe_add(&rr, &tt); /* rr = R = T^2-U1*U2 (3) */
/** If lambda = R/M = 0/0 we have a problem (except in the "trivial"
* case that Z = z1z2 = 0, and this is special-cased later on). */
degenerate = secp256k1_fe_normalizes_to_zero(&m) &
secp256k1_fe_normalizes_to_zero(&rr);
/* This only occurs when y1 == -y2 and x1^3 == x2^3, but x1 != x2.
* This means either x1 == beta*x2 or beta*x1 == x2, where beta is
* a nontrivial cube root of one. In either case, an alternate
* non-indeterminate expression for lambda is (y1 - y2)/(x1 - x2),
* so we set R/M equal to this. */
rr_alt = s1;
secp256k1_fe_mul_int(&rr_alt, 2); /* rr = Y1*Z2^3 - Y2*Z1^3 (2) */
secp256k1_fe_add(&m_alt, &u1); /* Malt = X1*Z2^2 - X2*Z1^2 */
secp256k1_fe_cmov(&rr_alt, &rr, !degenerate);
secp256k1_fe_cmov(&m_alt, &m, !degenerate);
/* Now Ralt / Malt = lambda and is guaranteed not to be 0/0.
* From here on out Ralt and Malt represent the numerator
* and denominator of lambda; R and M represent the explicit
* expressions x1^2 + x2^2 + x1x2 and y1 + y2. */
secp256k1_fe_sqr(&n, &m_alt); /* n = Malt^2 (1) */
secp256k1_fe_mul(&q, &n, &t); /* q = Q = T*Malt^2 (1) */
/* These two lines use the observation that either M == Malt or M == 0,
* so M^3 * Malt is either Malt^4 (which is computed by squaring), or
* zero (which is "computed" by cmov). So the cost is one squaring
* versus two multiplications. */
secp256k1_fe_sqr(&n, &n);
secp256k1_fe_cmov(&n, &m, degenerate); /* n = M^3 * Malt (2) */
secp256k1_fe_sqr(&t, &rr_alt); /* t = Ralt^2 (1) */
secp256k1_fe_mul(&r->z, &a->z, &m_alt); /* r->z = Malt*Z (1) */
infinity = secp256k1_fe_normalizes_to_zero(&r->z) * (1 - a->infinity);
secp256k1_fe_mul_int(&r->z, 2); /* r->z = Z3 = 2*Malt*Z (2) */
secp256k1_fe_negate(&q, &q, 1); /* q = -Q (2) */
secp256k1_fe_add(&t, &q); /* t = Ralt^2-Q (3) */
secp256k1_fe_normalize_weak(&t);
r->x = t; /* r->x = Ralt^2-Q (1) */
secp256k1_fe_mul_int(&t, 2); /* t = 2*x3 (2) */
secp256k1_fe_add(&t, &q); /* t = 2*x3 - Q: (4) */
secp256k1_fe_mul(&t, &t, &rr_alt); /* t = Ralt*(2*x3 - Q) (1) */
secp256k1_fe_add(&t, &n); /* t = Ralt*(2*x3 - Q) + M^3*Malt (3) */
secp256k1_fe_negate(&r->y, &t, 3); /* r->y = Ralt*(Q - 2x3) - M^3*Malt (4) */
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_mul_int(&r->x, 4); /* r->x = X3 = 4*(Ralt^2-Q) */
secp256k1_fe_mul_int(&r->y, 4); /* r->y = Y3 = 4*Ralt*(Q - 2x3) - 4*M^3*Malt (4) */
/** In case a->infinity == 1, replace r with (b->x, b->y, 1). */
secp256k1_fe_cmov(&r->x, &b->x, a->infinity);
secp256k1_fe_cmov(&r->y, &b->y, a->infinity);
secp256k1_fe_cmov(&r->z, &fe_1, a->infinity);
r->infinity = infinity;
}
static void secp256k1_gej_rescale(secp256k1_gej *r, const secp256k1_fe *s) {
/* Operations: 4 mul, 1 sqr */
secp256k1_fe zz;
VERIFY_CHECK(!secp256k1_fe_is_zero(s));
secp256k1_fe_sqr(&zz, s);
secp256k1_fe_mul(&r->x, &r->x, &zz); /* r->x *= s^2 */
secp256k1_fe_mul(&r->y, &r->y, &zz);
secp256k1_fe_mul(&r->y, &r->y, s); /* r->y *= s^3 */
secp256k1_fe_mul(&r->z, &r->z, s); /* r->z *= s */
}
static void secp256k1_ge_to_storage(secp256k1_ge_storage *r, const secp256k1_ge *a) {
secp256k1_fe x, y;
VERIFY_CHECK(!a->infinity);
x = a->x;
secp256k1_fe_normalize(&x);
y = a->y;
secp256k1_fe_normalize(&y);
secp256k1_fe_to_storage(&r->x, &x);
secp256k1_fe_to_storage(&r->y, &y);
}
static void secp256k1_ge_from_storage(secp256k1_ge *r, const secp256k1_ge_storage *a) {
secp256k1_fe_from_storage(&r->x, &a->x);
secp256k1_fe_from_storage(&r->y, &a->y);
r->infinity = 0;
}
static SECP256K1_INLINE void secp256k1_ge_storage_cmov(secp256k1_ge_storage *r, const secp256k1_ge_storage *a, int flag) {
secp256k1_fe_storage_cmov(&r->x, &a->x, flag);
secp256k1_fe_storage_cmov(&r->y, &a->y, flag);
}
#ifdef USE_ENDOMORPHISM
static void secp256k1_ge_mul_lambda(secp256k1_ge *r, const secp256k1_ge *a) {
static const secp256k1_fe beta = SECP256K1_FE_CONST(
0x7ae96a2bul, 0x657c0710ul, 0x6e64479eul, 0xac3434e9ul,
0x9cf04975ul, 0x12f58995ul, 0xc1396c28ul, 0x719501eeul
);
*r = *a;
secp256k1_fe_mul(&r->x, &r->x, &beta);
}
#endif
#endif

@ -34,7 +34,7 @@ typedef struct {
int retry;
} secp256k1_rfc6979_hmac_sha256_t;
static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256_t *rng, const unsigned char *key, size_t keylen, const unsigned char *msg, size_t msglen, const unsigned char *rnd, size_t rndlen);
static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256_t *rng, const unsigned char *key, size_t keylen);
static void secp256k1_rfc6979_hmac_sha256_generate(secp256k1_rfc6979_hmac_sha256_t *rng, unsigned char *out, size_t outlen);
static void secp256k1_rfc6979_hmac_sha256_finalize(secp256k1_rfc6979_hmac_sha256_t *rng);

@ -202,7 +202,7 @@ static void secp256k1_hmac_sha256_finalize(secp256k1_hmac_sha256_t *hash, unsign
}
static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256_t *rng, const unsigned char *key, size_t keylen, const unsigned char *msg, size_t msglen, const unsigned char *rnd, size_t rndlen) {
static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256_t *rng, const unsigned char *key, size_t keylen) {
secp256k1_hmac_sha256_t hmac;
static const unsigned char zero[1] = {0x00};
static const unsigned char one[1] = {0x01};
@ -215,11 +215,6 @@ static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha2
secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
secp256k1_hmac_sha256_write(&hmac, zero, 1);
secp256k1_hmac_sha256_write(&hmac, key, keylen);
secp256k1_hmac_sha256_write(&hmac, msg, msglen);
if (rnd && rndlen) {
/* RFC6979 3.6 "Additional data". */
secp256k1_hmac_sha256_write(&hmac, rnd, rndlen);
}
secp256k1_hmac_sha256_finalize(&hmac, rng->k);
secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
@ -230,11 +225,6 @@ static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha2
secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
secp256k1_hmac_sha256_write(&hmac, one, 1);
secp256k1_hmac_sha256_write(&hmac, key, keylen);
secp256k1_hmac_sha256_write(&hmac, msg, msglen);
if (rnd && rndlen) {
/* RFC6979 3.6 "Additional data". */
secp256k1_hmac_sha256_write(&hmac, rnd, rndlen);
}
secp256k1_hmac_sha256_finalize(&hmac, rng->k);
secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
secp256k1_hmac_sha256_write(&hmac, rng->v, 32);

@ -0,0 +1,9 @@
include_HEADERS += include/secp256k1_ecdh.h
noinst_HEADERS += src/modules/ecdh/main_impl.h
noinst_HEADERS += src/modules/ecdh/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_ecdh
bench_ecdh_SOURCES = src/bench_ecdh.c
bench_ecdh_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_ecdh_LDFLAGS = -static
endif

@ -0,0 +1,54 @@
/**********************************************************************
* Copyright (c) 2015 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_ECDH_MAIN_
#define _SECP256K1_MODULE_ECDH_MAIN_
#include "include/secp256k1_ecdh.h"
#include "ecmult_const_impl.h"
int secp256k1_ecdh(const secp256k1_context* ctx, unsigned char *result, const secp256k1_pubkey *point, const unsigned char *scalar) {
int ret = 0;
int overflow = 0;
secp256k1_gej res;
secp256k1_ge pt;
secp256k1_scalar s;
ARG_CHECK(result != NULL);
ARG_CHECK(point != NULL);
ARG_CHECK(scalar != NULL);
(void)ctx;
secp256k1_pubkey_load(ctx, &pt, point);
secp256k1_scalar_set_b32(&s, scalar, &overflow);
if (overflow || secp256k1_scalar_is_zero(&s)) {
ret = 0;
} else {
unsigned char x[32];
unsigned char y[1];
secp256k1_sha256_t sha;
secp256k1_ecmult_const(&res, &pt, &s);
secp256k1_ge_set_gej(&pt, &res);
/* Compute a hash of the point in compressed form
* Note we cannot use secp256k1_eckey_pubkey_serialize here since it does not
* expect its output to be secret and has a timing sidechannel. */
secp256k1_fe_normalize(&pt.x);
secp256k1_fe_normalize(&pt.y);
secp256k1_fe_get_b32(x, &pt.x);
y[0] = 0x02 | secp256k1_fe_is_odd(&pt.y);
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, y, sizeof(y));
secp256k1_sha256_write(&sha, x, sizeof(x));
secp256k1_sha256_finalize(&sha, result);
ret = 1;
}
secp256k1_scalar_clear(&s);
return ret;
}
#endif

@ -0,0 +1,75 @@
/**********************************************************************
* Copyright (c) 2015 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_ECDH_TESTS_
#define _SECP256K1_MODULE_ECDH_TESTS_
void test_ecdh_generator_basepoint(void) {
unsigned char s_one[32] = { 0 };
secp256k1_pubkey point[2];
int i;
s_one[31] = 1;
/* Check against pubkey creation when the basepoint is the generator */
for (i = 0; i < 100; ++i) {
secp256k1_sha256_t sha;
unsigned char s_b32[32];
unsigned char output_ecdh[32];
unsigned char output_ser[32];
unsigned char point_ser[33];
size_t point_ser_len = sizeof(point_ser);
secp256k1_scalar s;
random_scalar_order(&s);
secp256k1_scalar_get_b32(s_b32, &s);
/* compute using ECDH function */
CHECK(secp256k1_ec_pubkey_create(ctx, &point[0], s_one) == 1);
CHECK(secp256k1_ecdh(ctx, output_ecdh, &point[0], s_b32) == 1);
/* compute "explicitly" */
CHECK(secp256k1_ec_pubkey_create(ctx, &point[1], s_b32) == 1);
CHECK(secp256k1_ec_pubkey_serialize(ctx, point_ser, &point_ser_len, &point[1], SECP256K1_EC_COMPRESSED) == 1);
CHECK(point_ser_len == sizeof(point_ser));
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, point_ser, point_ser_len);
secp256k1_sha256_finalize(&sha, output_ser);
/* compare */
CHECK(memcmp(output_ecdh, output_ser, sizeof(output_ser)) == 0);
}
}
void test_bad_scalar(void) {
unsigned char s_zero[32] = { 0 };
unsigned char s_overflow[32] = {
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
0xba, 0xae, 0xdc, 0xe6, 0xaf, 0x48, 0xa0, 0x3b,
0xbf, 0xd2, 0x5e, 0x8c, 0xd0, 0x36, 0x41, 0x41
};
unsigned char s_rand[32] = { 0 };
unsigned char output[32];
secp256k1_scalar rand;
secp256k1_pubkey point;
/* Create random point */
random_scalar_order(&rand);
secp256k1_scalar_get_b32(s_rand, &rand);
CHECK(secp256k1_ec_pubkey_create(ctx, &point, s_rand) == 1);
/* Try to multiply it by bad values */
CHECK(secp256k1_ecdh(ctx, output, &point, s_zero) == 0);
CHECK(secp256k1_ecdh(ctx, output, &point, s_overflow) == 0);
/* ...and a good one */
s_overflow[31] -= 1;
CHECK(secp256k1_ecdh(ctx, output, &point, s_overflow) == 1);
}
void run_ecdh_tests(void) {
test_ecdh_generator_basepoint();
test_bad_scalar();
}
#endif

@ -0,0 +1,9 @@
include_HEADERS += include/secp256k1_recovery.h
noinst_HEADERS += src/modules/recovery/main_impl.h
noinst_HEADERS += src/modules/recovery/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_recover
bench_recover_SOURCES = src/bench_recover.c
bench_recover_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_recover_LDFLAGS = -static
endif

@ -0,0 +1,156 @@
/**********************************************************************
* Copyright (c) 2013-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_RECOVERY_MAIN_
#define _SECP256K1_MODULE_RECOVERY_MAIN_
#include "include/secp256k1_recovery.h"
static void secp256k1_ecdsa_recoverable_signature_load(const secp256k1_context* ctx, secp256k1_scalar* r, secp256k1_scalar* s, int* recid, const secp256k1_ecdsa_recoverable_signature* sig) {
(void)ctx;
if (sizeof(secp256k1_scalar) == 32) {
/* When the secp256k1_scalar type is exactly 32 byte, use its
* representation inside secp256k1_ecdsa_signature, as conversion is very fast.
* Note that secp256k1_ecdsa_signature_save must use the same representation. */
memcpy(r, &sig->data[0], 32);
memcpy(s, &sig->data[32], 32);
} else {
secp256k1_scalar_set_b32(r, &sig->data[0], NULL);
secp256k1_scalar_set_b32(s, &sig->data[32], NULL);
}
*recid = sig->data[64];
}
static void secp256k1_ecdsa_recoverable_signature_save(secp256k1_ecdsa_recoverable_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s, int recid) {
if (sizeof(secp256k1_scalar) == 32) {
memcpy(&sig->data[0], r, 32);
memcpy(&sig->data[32], s, 32);
} else {
secp256k1_scalar_get_b32(&sig->data[0], r);
secp256k1_scalar_get_b32(&sig->data[32], s);
}
sig->data[64] = recid;
}
int secp256k1_ecdsa_recoverable_signature_parse_compact(const secp256k1_context* ctx, secp256k1_ecdsa_recoverable_signature* sig, const unsigned char *input64, int recid) {
secp256k1_scalar r, s;
int ret = 1;
int overflow = 0;
(void)ctx;
ARG_CHECK(sig != NULL);
ARG_CHECK(input64 != NULL);
ARG_CHECK(recid >= 0 && recid <= 3);
secp256k1_scalar_set_b32(&r, &input64[0], &overflow);
ret &= !overflow;
secp256k1_scalar_set_b32(&s, &input64[32], &overflow);
ret &= !overflow;
if (ret) {
secp256k1_ecdsa_recoverable_signature_save(sig, &r, &s, recid);
} else {
memset(sig, 0, sizeof(*sig));
}
return ret;
}
int secp256k1_ecdsa_recoverable_signature_serialize_compact(const secp256k1_context* ctx, unsigned char *output64, int *recid, const secp256k1_ecdsa_recoverable_signature* sig) {
secp256k1_scalar r, s;
(void)ctx;
ARG_CHECK(output64 != NULL);
ARG_CHECK(sig != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, recid, sig);
secp256k1_scalar_get_b32(&output64[0], &r);
secp256k1_scalar_get_b32(&output64[32], &s);
return 1;
}
int secp256k1_ecdsa_recoverable_signature_convert(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const secp256k1_ecdsa_recoverable_signature* sigin) {
secp256k1_scalar r, s;
int recid;
(void)ctx;
ARG_CHECK(sig != NULL);
ARG_CHECK(sigin != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, &recid, sigin);
secp256k1_ecdsa_signature_save(sig, &r, &s);
return 1;
}
int secp256k1_ecdsa_sign_recoverable(const secp256k1_context* ctx, secp256k1_ecdsa_recoverable_signature *signature, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) {
secp256k1_scalar r, s;
secp256k1_scalar sec, non, msg;
int recid;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(signature != NULL);
ARG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
/* Fail if the secret key is invalid. */
if (!overflow && !secp256k1_scalar_is_zero(&sec)) {
unsigned int count = 0;
secp256k1_scalar_set_b32(&msg, msg32, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, seckey, msg32, NULL, (void*)noncedata, count);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_ecdsa_sig_sign(&ctx->ecmult_gen_ctx, &r, &s, &sec, &msg, &non, &recid)) {
break;
}
}
count++;
}
secp256k1_scalar_clear(&msg);
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
}
if (ret) {
secp256k1_ecdsa_recoverable_signature_save(signature, &r, &s, recid);
} else {
memset(signature, 0, sizeof(*signature));
}
return ret;
}
int secp256k1_ecdsa_recover(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const secp256k1_ecdsa_recoverable_signature *signature, const unsigned char *msg32) {
secp256k1_ge q;
secp256k1_scalar r, s;
secp256k1_scalar m;
int recid;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(signature != NULL);
ARG_CHECK(pubkey != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, &recid, signature);
ARG_CHECK(recid >= 0 && recid < 4);
secp256k1_scalar_set_b32(&m, msg32, NULL);
if (secp256k1_ecdsa_sig_recover(&ctx->ecmult_ctx, &r, &s, &q, &m, recid)) {
secp256k1_pubkey_save(pubkey, &q);
return 1;
} else {
memset(pubkey, 0, sizeof(*pubkey));
return 0;
}
}
#endif

@ -0,0 +1,249 @@
/**********************************************************************
* Copyright (c) 2013-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_RECOVERY_TESTS_
#define _SECP256K1_MODULE_RECOVERY_TESTS_
void test_ecdsa_recovery_end_to_end(void) {
unsigned char extra[32] = {0x00};
unsigned char privkey[32];
unsigned char message[32];
secp256k1_ecdsa_signature signature[5];
secp256k1_ecdsa_recoverable_signature rsignature[5];
unsigned char sig[74];
secp256k1_pubkey pubkey;
secp256k1_pubkey recpubkey;
int recid = 0;
/* Generate a random key and message. */
{
secp256k1_scalar msg, key;
random_scalar_order_test(&msg);
random_scalar_order_test(&key);
secp256k1_scalar_get_b32(privkey, &key);
secp256k1_scalar_get_b32(message, &msg);
}
/* Construct and verify corresponding public key. */
CHECK(secp256k1_ec_seckey_verify(ctx, privkey) == 1);
CHECK(secp256k1_ec_pubkey_create(ctx, &pubkey, privkey) == 1);
/* Serialize/parse compact and verify/recover. */
extra[0] = 0;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[0], message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[4], message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[1], message, privkey, NULL, extra) == 1);
extra[31] = 1;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[2], message, privkey, NULL, extra) == 1);
extra[31] = 0;
extra[0] = 1;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[3], message, privkey, NULL, extra) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_serialize_compact(ctx, sig, &recid, &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 1);
memset(&rsignature[4], 0, sizeof(rsignature[4]));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 1);
/* Parse compact (with recovery id) and recover. */
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &recpubkey, &rsignature[4], message) == 1);
CHECK(memcmp(&pubkey, &recpubkey, sizeof(pubkey)) == 0);
/* Serialize/destroy/parse signature and verify again. */
CHECK(secp256k1_ecdsa_recoverable_signature_serialize_compact(ctx, sig, &recid, &rsignature[4]) == 1);
sig[secp256k1_rand32() % 64] += 1 + (secp256k1_rand32() % 255);
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 0);
/* Recover again */
CHECK(secp256k1_ecdsa_recover(ctx, &recpubkey, &rsignature[4], message) == 0 ||
memcmp(&pubkey, &recpubkey, sizeof(pubkey)) != 0);
}
/* Tests several edge cases. */
void test_ecdsa_recovery_edge_cases(void) {
const unsigned char msg32[32] = {
'T', 'h', 'i', 's', ' ', 'i', 's', ' ',
'a', ' ', 'v', 'e', 'r', 'y', ' ', 's',
'e', 'c', 'r', 'e', 't', ' ', 'm', 'e',
's', 's', 'a', 'g', 'e', '.', '.', '.'
};
const unsigned char sig64[64] = {
/* Generated by signing the above message with nonce 'This is the nonce we will use...'
* and secret key 0 (which is not valid), resulting in recid 0. */
0x67, 0xCB, 0x28, 0x5F, 0x9C, 0xD1, 0x94, 0xE8,
0x40, 0xD6, 0x29, 0x39, 0x7A, 0xF5, 0x56, 0x96,
0x62, 0xFD, 0xE4, 0x46, 0x49, 0x99, 0x59, 0x63,
0x17, 0x9A, 0x7D, 0xD1, 0x7B, 0xD2, 0x35, 0x32,
0x4B, 0x1B, 0x7D, 0xF3, 0x4C, 0xE1, 0xF6, 0x8E,
0x69, 0x4F, 0xF6, 0xF1, 0x1A, 0xC7, 0x51, 0xDD,
0x7D, 0xD7, 0x3E, 0x38, 0x7E, 0xE4, 0xFC, 0x86,
0x6E, 0x1B, 0xE8, 0xEC, 0xC7, 0xDD, 0x95, 0x57
};
secp256k1_pubkey pubkey;
/* signature (r,s) = (4,4), which can be recovered with all 4 recids. */
const unsigned char sigb64[64] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
secp256k1_pubkey pubkeyb;
secp256k1_ecdsa_recoverable_signature rsig;
secp256k1_ecdsa_signature sig;
int recid;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 0));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 1));
CHECK(secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 2));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 3));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
for (recid = 0; recid < 4; recid++) {
int i;
int recid2;
/* (4,4) encoded in DER. */
unsigned char sigbder[8] = {0x30, 0x06, 0x02, 0x01, 0x04, 0x02, 0x01, 0x04};
unsigned char sigcder_zr[7] = {0x30, 0x05, 0x02, 0x00, 0x02, 0x01, 0x01};
unsigned char sigcder_zs[7] = {0x30, 0x05, 0x02, 0x01, 0x01, 0x02, 0x00};
unsigned char sigbderalt1[39] = {
0x30, 0x25, 0x02, 0x20, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x04, 0x02, 0x01, 0x04,
};
unsigned char sigbderalt2[39] = {
0x30, 0x25, 0x02, 0x01, 0x04, 0x02, 0x20, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
unsigned char sigbderalt3[40] = {
0x30, 0x26, 0x02, 0x21, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x04, 0x02, 0x01, 0x04,
};
unsigned char sigbderalt4[40] = {
0x30, 0x26, 0x02, 0x01, 0x04, 0x02, 0x21, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
/* (order + r,4) encoded in DER. */
unsigned char sigbderlong[40] = {
0x30, 0x26, 0x02, 0x21, 0x00, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xBA, 0xAE, 0xDC,
0xE6, 0xAF, 0x48, 0xA0, 0x3B, 0xBF, 0xD2, 0x5E,
0x8C, 0xD0, 0x36, 0x41, 0x45, 0x02, 0x01, 0x04
};
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigb64, recid) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
for (recid2 = 0; recid2 < 4; recid2++) {
secp256k1_pubkey pubkey2b;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigb64, recid2) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkey2b, &rsig, msg32) == 1);
/* Verifying with (order + r,4) should always fail. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderlong, sizeof(sigbderlong)) == 0);
}
/* DER parsing tests. */
/* Zero length r/s. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder_zr, sizeof(sigcder_zr)) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder_zs, sizeof(sigcder_zs)) == 0);
/* Leading zeros. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt1, sizeof(sigbderalt1)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt2, sizeof(sigbderalt2)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt3, sizeof(sigbderalt3)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt4, sizeof(sigbderalt4)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
sigbderalt3[4] = 1;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt3, sizeof(sigbderalt3)) == 0);
sigbderalt4[7] = 1;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt4, sizeof(sigbderalt4)) == 0);
/* Damage signature. */
sigbder[7]++;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 0);
sigbder[7]--;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, 6) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder) - 1) == 0);
for(i = 0; i < 8; i++) {
int c;
unsigned char orig = sigbder[i];
/*Try every single-byte change.*/
for (c = 0; c < 256; c++) {
if (c == orig ) {
continue;
}
sigbder[i] = c;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 0 || secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 0);
}
sigbder[i] = orig;
}
}
/* Test r/s equal to zero */
{
/* (1,1) encoded in DER. */
unsigned char sigcder[8] = {0x30, 0x06, 0x02, 0x01, 0x01, 0x02, 0x01, 0x01};
unsigned char sigc64[64] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
};
secp256k1_pubkey pubkeyc;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyc, &rsig, msg32) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 1);
sigcder[4] = 0;
sigc64[31] = 0;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 0);
sigcder[4] = 1;
sigcder[7] = 0;
sigc64[31] = 1;
sigc64[63] = 0;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 0);
}
}
void run_recovery_tests(void) {
int i;
for (i = 0; i < 64*count; i++) {
test_ecdsa_recovery_end_to_end();
}
test_ecdsa_recovery_edge_cases();
}
#endif

@ -0,0 +1,11 @@
include_HEADERS += include/secp256k1_schnorr.h
noinst_HEADERS += src/modules/schnorr/main_impl.h
noinst_HEADERS += src/modules/schnorr/schnorr.h
noinst_HEADERS += src/modules/schnorr/schnorr_impl.h
noinst_HEADERS += src/modules/schnorr/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_schnorr_verify
bench_schnorr_verify_SOURCES = src/bench_schnorr_verify.c
bench_schnorr_verify_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_schnorr_verify_LDFLAGS = -static
endif

@ -0,0 +1,164 @@
/**********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef SECP256K1_MODULE_SCHNORR_MAIN
#define SECP256K1_MODULE_SCHNORR_MAIN
#include "include/secp256k1_schnorr.h"
#include "modules/schnorr/schnorr_impl.h"
static void secp256k1_schnorr_msghash_sha256(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32) {
secp256k1_sha256_t sha;
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, r32, 32);
secp256k1_sha256_write(&sha, msg32, 32);
secp256k1_sha256_finalize(&sha, h32);
}
static const unsigned char secp256k1_schnorr_algo16[17] = "Schnorr+SHA256 ";
int secp256k1_schnorr_sign(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) {
secp256k1_scalar sec, non;
int ret = 0;
int overflow = 0;
unsigned int count = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, msg32, seckey, secp256k1_schnorr_algo16, (void*)noncedata, count);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64, &sec, &non, NULL, secp256k1_schnorr_msghash_sha256, msg32)) {
break;
}
}
count++;
}
if (!ret) {
memset(sig64, 0, 64);
}
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
return ret;
}
int secp256k1_schnorr_verify(const secp256k1_context* ctx, const unsigned char *sig64, const unsigned char *msg32, const secp256k1_pubkey *pubkey) {
secp256k1_ge q;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(pubkey != NULL);
secp256k1_pubkey_load(ctx, &q, pubkey);
return secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64, &q, secp256k1_schnorr_msghash_sha256, msg32);
}
int secp256k1_schnorr_recover(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *sig64, const unsigned char *msg32) {
secp256k1_ge q;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(pubkey != NULL);
if (secp256k1_schnorr_sig_recover(&ctx->ecmult_ctx, sig64, &q, secp256k1_schnorr_msghash_sha256, msg32)) {
secp256k1_pubkey_save(pubkey, &q);
return 1;
} else {
memset(pubkey, 0, sizeof(*pubkey));
return 0;
}
}
int secp256k1_schnorr_generate_nonce_pair(const secp256k1_context* ctx, secp256k1_pubkey *pubnonce, unsigned char *privnonce32, const unsigned char *sec32, const unsigned char *msg32, secp256k1_nonce_function noncefp, const void* noncedata) {
int count = 0;
int ret = 1;
secp256k1_gej Qj;
secp256k1_ge Q;
secp256k1_scalar sec;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sec32 != NULL);
ARG_CHECK(pubnonce != NULL);
ARG_CHECK(privnonce32 != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
do {
int overflow;
ret = noncefp(privnonce32, sec32, msg32, secp256k1_schnorr_algo16, (void*)noncedata, count++);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&sec, privnonce32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&sec)) {
continue;
}
secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &Qj, &sec);
secp256k1_ge_set_gej(&Q, &Qj);
secp256k1_pubkey_save(pubnonce, &Q);
break;
} while(1);
secp256k1_scalar_clear(&sec);
if (!ret) {
memset(pubnonce, 0, sizeof(*pubnonce));
}
return ret;
}
int secp256k1_schnorr_partial_sign(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char *msg32, const unsigned char *sec32, const secp256k1_pubkey *pubnonce_others, const unsigned char *secnonce32) {
int overflow = 0;
secp256k1_scalar sec, non;
secp256k1_ge pubnon;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(sec32 != NULL);
ARG_CHECK(secnonce32 != NULL);
ARG_CHECK(pubnonce_others != NULL);
secp256k1_scalar_set_b32(&sec, sec32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&sec)) {
return -1;
}
secp256k1_scalar_set_b32(&non, secnonce32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&non)) {
return -1;
}
secp256k1_pubkey_load(ctx, &pubnon, pubnonce_others);
return secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64, &sec, &non, &pubnon, secp256k1_schnorr_msghash_sha256, msg32);
}
int secp256k1_schnorr_partial_combine(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char * const *sig64sin, int n) {
ARG_CHECK(sig64 != NULL);
ARG_CHECK(n >= 1);
ARG_CHECK(sig64sin != NULL);
return secp256k1_schnorr_sig_combine(sig64, n, sig64sin);
}
#endif

@ -0,0 +1,20 @@
/***********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php. *
***********************************************************************/
#ifndef _SECP256K1_MODULE_SCHNORR_H_
#define _SECP256K1_MODULE_SCHNORR_H_
#include "scalar.h"
#include "group.h"
typedef void (*secp256k1_schnorr_msghash)(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32);
static int secp256k1_schnorr_sig_sign(const secp256k1_ecmult_gen_context* ctx, unsigned char *sig64, const secp256k1_scalar *key, const secp256k1_scalar *nonce, const secp256k1_ge *pubnonce, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_verify(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, const secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_recover(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_combine(unsigned char *sig64, int n, const unsigned char * const *sig64ins);
#endif

@ -0,0 +1,207 @@
/***********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php. *
***********************************************************************/
#ifndef _SECP256K1_SCHNORR_IMPL_H_
#define _SECP256K1_SCHNORR_IMPL_H_
#include <string.h>
#include "schnorr.h"
#include "num.h"
#include "field.h"
#include "group.h"
#include "ecmult.h"
#include "ecmult_gen.h"
/**
* Custom Schnorr-based signature scheme. They support multiparty signing, public key
* recovery and batch validation.
*
* Rationale for verifying R's y coordinate:
* In order to support batch validation and public key recovery, the full R point must
* be known to verifiers, rather than just its x coordinate. In order to not risk
* being more strict in batch validation than normal validation, validators must be
* required to reject signatures with incorrect y coordinate. This is only possible
* by including a (relatively slow) field inverse, or a field square root. However,
* batch validation offers potentially much higher benefits than this cost.
*
* Rationale for having an implicit y coordinate oddness:
* If we commit to having the full R point known to verifiers, there are two mechanism.
* Either include its oddness in the signature, or give it an implicit fixed value.
* As the R y coordinate can be flipped by a simple negation of the nonce, we choose the
* latter, as it comes with nearly zero impact on signing or validation performance, and
* saves a byte in the signature.
*
* Signing:
* Inputs: 32-byte message m, 32-byte scalar key x (!=0), 32-byte scalar nonce k (!=0)
*
* Compute point R = k * G. Reject nonce if R's y coordinate is odd (or negate nonce).
* Compute 32-byte r, the serialization of R's x coordinate.
* Compute scalar h = Hash(r || m). Reject nonce if h == 0 or h >= order.
* Compute scalar s = k - h * x.
* The signature is (r, s).
*
*
* Verification:
* Inputs: 32-byte message m, public key point Q, signature: (32-byte r, scalar s)
*
* Signature is invalid if s >= order.
* Signature is invalid if r >= p.
* Compute scalar h = Hash(r || m). Signature is invalid if h == 0 or h >= order.
* Option 1 (faster for single verification):
* Compute point R = h * Q + s * G. Signature is invalid if R is infinity or R's y coordinate is odd.
* Signature is valid if the serialization of R's x coordinate equals r.
* Option 2 (allows batch validation and pubkey recovery):
* Decompress x coordinate r into point R, with odd y coordinate. Fail if R is not on the curve.
* Signature is valid if R + h * Q + s * G == 0.
*/
static int secp256k1_schnorr_sig_sign(const secp256k1_ecmult_gen_context* ctx, unsigned char *sig64, const secp256k1_scalar *key, const secp256k1_scalar *nonce, const secp256k1_ge *pubnonce, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Rj;
secp256k1_ge Ra;
unsigned char h32[32];
secp256k1_scalar h, s;
int overflow;
secp256k1_scalar n;
if (secp256k1_scalar_is_zero(key) || secp256k1_scalar_is_zero(nonce)) {
return 0;
}
n = *nonce;
secp256k1_ecmult_gen(ctx, &Rj, &n);
if (pubnonce != NULL) {
secp256k1_gej_add_ge(&Rj, &Rj, pubnonce);
}
secp256k1_ge_set_gej(&Ra, &Rj);
secp256k1_fe_normalize(&Ra.y);
if (secp256k1_fe_is_odd(&Ra.y)) {
/* R's y coordinate is odd, which is not allowed (see rationale above).
Force it to be even by negating the nonce. Note that this even works
for multiparty signing, as the R point is known to all participants,
which can all decide to flip the sign in unison, resulting in the
overall R point to be negated too. */
secp256k1_scalar_negate(&n, &n);
}
secp256k1_fe_normalize(&Ra.x);
secp256k1_fe_get_b32(sig64, &Ra.x);
hash(h32, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, h32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
secp256k1_scalar_clear(&n);
return 0;
}
secp256k1_scalar_mul(&s, &h, key);
secp256k1_scalar_negate(&s, &s);
secp256k1_scalar_add(&s, &s, &n);
secp256k1_scalar_clear(&n);
secp256k1_scalar_get_b32(sig64 + 32, &s);
return 1;
}
static int secp256k1_schnorr_sig_verify(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, const secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Qj, Rj;
secp256k1_ge Ra;
secp256k1_fe Rx;
secp256k1_scalar h, s;
unsigned char hh[32];
int overflow;
if (secp256k1_ge_is_infinity(pubkey)) {
return 0;
}
hash(hh, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, hh, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
return 0;
}
overflow = 0;
secp256k1_scalar_set_b32(&s, sig64 + 32, &overflow);
if (overflow) {
return 0;
}
if (!secp256k1_fe_set_b32(&Rx, sig64)) {
return 0;
}
secp256k1_gej_set_ge(&Qj, pubkey);
secp256k1_ecmult(ctx, &Rj, &Qj, &h, &s);
if (secp256k1_gej_is_infinity(&Rj)) {
return 0;
}
secp256k1_ge_set_gej_var(&Ra, &Rj);
secp256k1_fe_normalize_var(&Ra.y);
if (secp256k1_fe_is_odd(&Ra.y)) {
return 0;
}
return secp256k1_fe_equal_var(&Rx, &Ra.x);
}
static int secp256k1_schnorr_sig_recover(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Qj, Rj;
secp256k1_ge Ra;
secp256k1_fe Rx;
secp256k1_scalar h, s;
unsigned char hh[32];
int overflow;
hash(hh, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, hh, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
return 0;
}
overflow = 0;
secp256k1_scalar_set_b32(&s, sig64 + 32, &overflow);
if (overflow) {
return 0;
}
if (!secp256k1_fe_set_b32(&Rx, sig64)) {
return 0;
}
if (!secp256k1_ge_set_xo_var(&Ra, &Rx, 0)) {
return 0;
}
secp256k1_gej_set_ge(&Rj, &Ra);
secp256k1_scalar_inverse_var(&h, &h);
secp256k1_scalar_negate(&s, &s);
secp256k1_scalar_mul(&s, &s, &h);
secp256k1_ecmult(ctx, &Qj, &Rj, &h, &s);
if (secp256k1_gej_is_infinity(&Qj)) {
return 0;
}
secp256k1_ge_set_gej(pubkey, &Qj);
return 1;
}
static int secp256k1_schnorr_sig_combine(unsigned char *sig64, int n, const unsigned char * const *sig64ins) {
secp256k1_scalar s = SECP256K1_SCALAR_CONST(0, 0, 0, 0, 0, 0, 0, 0);
int i;
for (i = 0; i < n; i++) {
secp256k1_scalar si;
int overflow;
secp256k1_scalar_set_b32(&si, sig64ins[i] + 32, &overflow);
if (overflow) {
return -1;
}
if (i) {
if (memcmp(sig64ins[i - 1], sig64ins[i], 32) != 0) {
return -1;
}
}
secp256k1_scalar_add(&s, &s, &si);
}
if (secp256k1_scalar_is_zero(&s)) {
return 0;
}
memcpy(sig64, sig64ins[0], 32);
secp256k1_scalar_get_b32(sig64 + 32, &s);
secp256k1_scalar_clear(&s);
return 1;
}
#endif

@ -0,0 +1,175 @@
/**********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef SECP256K1_MODULE_SCHNORR_TESTS
#define SECP256K1_MODULE_SCHNORR_TESTS
#include "include/secp256k1_schnorr.h"
void test_schnorr_end_to_end(void) {
unsigned char privkey[32];
unsigned char message[32];
unsigned char schnorr_signature[64];
secp256k1_pubkey pubkey, recpubkey;
/* Generate a random key and message. */
{
secp256k1_scalar key;
random_scalar_order_test(&key);
secp256k1_scalar_get_b32(privkey, &key);
secp256k1_rand256_test(message);
}
/* Construct and verify corresponding public key. */
CHECK(secp256k1_ec_seckey_verify(ctx, privkey) == 1);
CHECK(secp256k1_ec_pubkey_create(ctx, &pubkey, privkey) == 1);
/* Schnorr sign. */
CHECK(secp256k1_schnorr_sign(ctx, schnorr_signature, message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_schnorr_verify(ctx, schnorr_signature, message, &pubkey) == 1);
CHECK(secp256k1_schnorr_recover(ctx, &recpubkey, schnorr_signature, message) == 1);
CHECK(memcmp(&pubkey, &recpubkey, sizeof(pubkey)) == 0);
/* Destroy signature and verify again. */
schnorr_signature[secp256k1_rand32() % 64] += 1 + (secp256k1_rand32() % 255);
CHECK(secp256k1_schnorr_verify(ctx, schnorr_signature, message, &pubkey) == 0);
CHECK(secp256k1_schnorr_recover(ctx, &recpubkey, schnorr_signature, message) != 1 ||
memcmp(&pubkey, &recpubkey, sizeof(pubkey)) != 0);
}
/** Horribly broken hash function. Do not use for anything but tests. */
void test_schnorr_hash(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32) {
int i;
for (i = 0; i < 32; i++) {
h32[i] = r32[i] ^ msg32[i];
}
}
void test_schnorr_sign_verify(void) {
unsigned char msg32[32];
unsigned char sig64[3][64];
secp256k1_gej pubkeyj[3];
secp256k1_ge pubkey[3];
secp256k1_scalar nonce[3], key[3];
int i = 0;
int k;
secp256k1_rand256_test(msg32);
for (k = 0; k < 3; k++) {
random_scalar_order_test(&key[k]);
do {
random_scalar_order_test(&nonce[k]);
if (secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64[k], &key[k], &nonce[k], NULL, &test_schnorr_hash, msg32)) {
break;
}
} while(1);
secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &pubkeyj[k], &key[k]);
secp256k1_ge_set_gej_var(&pubkey[k], &pubkeyj[k]);
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64[k], &pubkey[k], &test_schnorr_hash, msg32));
for (i = 0; i < 4; i++) {
int pos = secp256k1_rand32() % 64;
int mod = 1 + (secp256k1_rand32() % 255);
sig64[k][pos] ^= mod;
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64[k], &pubkey[k], &test_schnorr_hash, msg32) == 0);
sig64[k][pos] ^= mod;
}
}
}
void test_schnorr_threshold(void) {
unsigned char msg[32];
unsigned char sec[5][32];
secp256k1_pubkey pub[5];
unsigned char nonce[5][32];
secp256k1_pubkey pubnonce[5];
unsigned char sig[5][64];
const unsigned char* sigs[5];
unsigned char allsig[64];
const secp256k1_pubkey* pubs[5];
secp256k1_pubkey allpub;
int n, i;
int damage;
int ret = 0;
damage = (secp256k1_rand32() % 2) ? (1 + (secp256k1_rand32() % 4)) : 0;
secp256k1_rand256_test(msg);
n = 2 + (secp256k1_rand32() % 4);
for (i = 0; i < n; i++) {
do {
secp256k1_rand256_test(sec[i]);
} while (!secp256k1_ec_seckey_verify(ctx, sec[i]));
CHECK(secp256k1_ec_pubkey_create(ctx, &pub[i], sec[i]));
CHECK(secp256k1_schnorr_generate_nonce_pair(ctx, &pubnonce[i], nonce[i], msg, sec[i], NULL, NULL));
pubs[i] = &pub[i];
}
if (damage == 1) {
nonce[secp256k1_rand32() % n][secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
} else if (damage == 2) {
sec[secp256k1_rand32() % n][secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
}
for (i = 0; i < n; i++) {
secp256k1_pubkey allpubnonce;
const secp256k1_pubkey *pubnonces[4];
int j;
for (j = 0; j < i; j++) {
pubnonces[j] = &pubnonce[j];
}
for (j = i + 1; j < n; j++) {
pubnonces[j - 1] = &pubnonce[j];
}
CHECK(secp256k1_ec_pubkey_combine(ctx, &allpubnonce, pubnonces, n - 1));
ret |= (secp256k1_schnorr_partial_sign(ctx, sig[i], msg, sec[i], &allpubnonce, nonce[i]) != 1) * 1;
sigs[i] = sig[i];
}
if (damage == 3) {
sig[secp256k1_rand32() % n][secp256k1_rand32() % 64] ^= 1 + (secp256k1_rand32() % 255);
}
ret |= (secp256k1_ec_pubkey_combine(ctx, &allpub, pubs, n) != 1) * 2;
if ((ret & 1) == 0) {
ret |= (secp256k1_schnorr_partial_combine(ctx, allsig, sigs, n) != 1) * 4;
}
if (damage == 4) {
allsig[secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
}
if ((ret & 7) == 0) {
ret |= (secp256k1_schnorr_verify(ctx, allsig, msg, &allpub) != 1) * 8;
}
CHECK((ret == 0) == (damage == 0));
}
void test_schnorr_recovery(void) {
unsigned char msg32[32];
unsigned char sig64[64];
secp256k1_ge Q;
secp256k1_rand256_test(msg32);
secp256k1_rand256_test(sig64);
secp256k1_rand256_test(sig64 + 32);
if (secp256k1_schnorr_sig_recover(&ctx->ecmult_ctx, sig64, &Q, &test_schnorr_hash, msg32) == 1) {
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64, &Q, &test_schnorr_hash, msg32) == 1);
}
}
void run_schnorr_tests(void) {
int i;
for (i = 0; i < 32*count; i++) {
test_schnorr_end_to_end();
}
for (i = 0; i < 32 * count; i++) {
test_schnorr_sign_verify();
}
for (i = 0; i < 16 * count; i++) {
test_schnorr_recovery();
}
for (i = 0; i < 10 * count; i++) {
test_schnorr_threshold();
}
}
#endif

@ -20,48 +20,48 @@
#endif
/** Copy a number. */
static void secp256k1_num_copy(secp256k1_num_t *r, const secp256k1_num_t *a);
static void secp256k1_num_copy(secp256k1_num *r, const secp256k1_num *a);
/** Convert a number's absolute value to a binary big-endian string.
* There must be enough place. */
static void secp256k1_num_get_bin(unsigned char *r, unsigned int rlen, const secp256k1_num_t *a);
static void secp256k1_num_get_bin(unsigned char *r, unsigned int rlen, const secp256k1_num *a);
/** Set a number to the value of a binary big-endian string. */
static void secp256k1_num_set_bin(secp256k1_num_t *r, const unsigned char *a, unsigned int alen);
static void secp256k1_num_set_bin(secp256k1_num *r, const unsigned char *a, unsigned int alen);
/** Compute a modular inverse. The input must be less than the modulus. */
static void secp256k1_num_mod_inverse(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *m);
static void secp256k1_num_mod_inverse(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *m);
/** Compare the absolute value of two numbers. */
static int secp256k1_num_cmp(const secp256k1_num_t *a, const secp256k1_num_t *b);
static int secp256k1_num_cmp(const secp256k1_num *a, const secp256k1_num *b);
/** Test whether two number are equal (including sign). */
static int secp256k1_num_eq(const secp256k1_num_t *a, const secp256k1_num_t *b);
static int secp256k1_num_eq(const secp256k1_num *a, const secp256k1_num *b);
/** Add two (signed) numbers. */
static void secp256k1_num_add(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b);
static void secp256k1_num_add(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
/** Subtract two (signed) numbers. */
static void secp256k1_num_sub(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b);
static void secp256k1_num_sub(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
/** Multiply two (signed) numbers. */
static void secp256k1_num_mul(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b);
static void secp256k1_num_mul(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
/** Replace a number by its remainder modulo m. M's sign is ignored. The result is a number between 0 and m-1,
even if r was negative. */
static void secp256k1_num_mod(secp256k1_num_t *r, const secp256k1_num_t *m);
static void secp256k1_num_mod(secp256k1_num *r, const secp256k1_num *m);
/** Right-shift the passed number by bits bits. */
static void secp256k1_num_shift(secp256k1_num_t *r, int bits);
static void secp256k1_num_shift(secp256k1_num *r, int bits);
/** Check whether a number is zero. */
static int secp256k1_num_is_zero(const secp256k1_num_t *a);
static int secp256k1_num_is_zero(const secp256k1_num *a);
/** Check whether a number is strictly negative. */
static int secp256k1_num_is_neg(const secp256k1_num_t *a);
static int secp256k1_num_is_neg(const secp256k1_num *a);
/** Change a number's sign. */
static void secp256k1_num_negate(secp256k1_num_t *r);
static void secp256k1_num_negate(secp256k1_num *r);
#endif

@ -15,6 +15,6 @@ typedef struct {
mp_limb_t data[2*NUM_LIMBS];
int neg;
int limbs;
} secp256k1_num_t;
} secp256k1_num;
#endif

@ -15,18 +15,18 @@
#include "num.h"
#ifdef VERIFY
static void secp256k1_num_sanity(const secp256k1_num_t *a) {
static void secp256k1_num_sanity(const secp256k1_num *a) {
VERIFY_CHECK(a->limbs == 1 || (a->limbs > 1 && a->data[a->limbs-1] != 0));
}
#else
#define secp256k1_num_sanity(a) do { } while(0)
#endif
static void secp256k1_num_copy(secp256k1_num_t *r, const secp256k1_num_t *a) {
static void secp256k1_num_copy(secp256k1_num *r, const secp256k1_num *a) {
*r = *a;
}
static void secp256k1_num_get_bin(unsigned char *r, unsigned int rlen, const secp256k1_num_t *a) {
static void secp256k1_num_get_bin(unsigned char *r, unsigned int rlen, const secp256k1_num *a) {
unsigned char tmp[65];
int len = 0;
int shift = 0;
@ -42,7 +42,7 @@ static void secp256k1_num_get_bin(unsigned char *r, unsigned int rlen, const sec
memset(tmp, 0, sizeof(tmp));
}
static void secp256k1_num_set_bin(secp256k1_num_t *r, const unsigned char *a, unsigned int alen) {
static void secp256k1_num_set_bin(secp256k1_num *r, const unsigned char *a, unsigned int alen) {
int len;
VERIFY_CHECK(alen > 0);
VERIFY_CHECK(alen <= 64);
@ -59,7 +59,7 @@ static void secp256k1_num_set_bin(secp256k1_num_t *r, const unsigned char *a, un
}
}
static void secp256k1_num_add_abs(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b) {
static void secp256k1_num_add_abs(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b) {
mp_limb_t c = mpn_add(r->data, a->data, a->limbs, b->data, b->limbs);
r->limbs = a->limbs;
if (c != 0) {
@ -68,7 +68,7 @@ static void secp256k1_num_add_abs(secp256k1_num_t *r, const secp256k1_num_t *a,
}
}
static void secp256k1_num_sub_abs(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b) {
static void secp256k1_num_sub_abs(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b) {
mp_limb_t c = mpn_sub(r->data, a->data, a->limbs, b->data, b->limbs);
VERIFY_CHECK(c == 0);
r->limbs = a->limbs;
@ -77,7 +77,7 @@ static void secp256k1_num_sub_abs(secp256k1_num_t *r, const secp256k1_num_t *a,
}
}
static void secp256k1_num_mod(secp256k1_num_t *r, const secp256k1_num_t *m) {
static void secp256k1_num_mod(secp256k1_num *r, const secp256k1_num *m) {
secp256k1_num_sanity(r);
secp256k1_num_sanity(m);
@ -97,7 +97,7 @@ static void secp256k1_num_mod(secp256k1_num_t *r, const secp256k1_num_t *m) {
}
}
static void secp256k1_num_mod_inverse(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *m) {
static void secp256k1_num_mod_inverse(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *m) {
int i;
mp_limb_t g[NUM_LIMBS+1];
mp_limb_t u[NUM_LIMBS+1];
@ -142,15 +142,15 @@ static void secp256k1_num_mod_inverse(secp256k1_num_t *r, const secp256k1_num_t
memset(v, 0, sizeof(v));
}
static int secp256k1_num_is_zero(const secp256k1_num_t *a) {
static int secp256k1_num_is_zero(const secp256k1_num *a) {
return (a->limbs == 1 && a->data[0] == 0);
}
static int secp256k1_num_is_neg(const secp256k1_num_t *a) {
static int secp256k1_num_is_neg(const secp256k1_num *a) {
return (a->limbs > 1 || a->data[0] != 0) && a->neg;
}
static int secp256k1_num_cmp(const secp256k1_num_t *a, const secp256k1_num_t *b) {
static int secp256k1_num_cmp(const secp256k1_num *a, const secp256k1_num *b) {
if (a->limbs > b->limbs) {
return 1;
}
@ -160,7 +160,7 @@ static int secp256k1_num_cmp(const secp256k1_num_t *a, const secp256k1_num_t *b)
return mpn_cmp(a->data, b->data, a->limbs);
}
static int secp256k1_num_eq(const secp256k1_num_t *a, const secp256k1_num_t *b) {
static int secp256k1_num_eq(const secp256k1_num *a, const secp256k1_num *b) {
if (a->limbs > b->limbs) {
return 0;
}
@ -173,7 +173,7 @@ static int secp256k1_num_eq(const secp256k1_num_t *a, const secp256k1_num_t *b)
return mpn_cmp(a->data, b->data, a->limbs) == 0;
}
static void secp256k1_num_subadd(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b, int bneg) {
static void secp256k1_num_subadd(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b, int bneg) {
if (!(b->neg ^ bneg ^ a->neg)) { /* a and b have the same sign */
r->neg = a->neg;
if (a->limbs >= b->limbs) {
@ -192,19 +192,19 @@ static void secp256k1_num_subadd(secp256k1_num_t *r, const secp256k1_num_t *a, c
}
}
static void secp256k1_num_add(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b) {
static void secp256k1_num_add(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b) {
secp256k1_num_sanity(a);
secp256k1_num_sanity(b);
secp256k1_num_subadd(r, a, b, 0);
}
static void secp256k1_num_sub(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b) {
static void secp256k1_num_sub(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b) {
secp256k1_num_sanity(a);
secp256k1_num_sanity(b);
secp256k1_num_subadd(r, a, b, 1);
}
static void secp256k1_num_mul(secp256k1_num_t *r, const secp256k1_num_t *a, const secp256k1_num_t *b) {
static void secp256k1_num_mul(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b) {
mp_limb_t tmp[2*NUM_LIMBS+1];
secp256k1_num_sanity(a);
secp256k1_num_sanity(b);
@ -231,13 +231,13 @@ static void secp256k1_num_mul(secp256k1_num_t *r, const secp256k1_num_t *a, cons
memset(tmp, 0, sizeof(tmp));
}
static void secp256k1_num_shift(secp256k1_num_t *r, int bits) {
int i;
static void secp256k1_num_shift(secp256k1_num *r, int bits) {
if (bits % GMP_NUMB_BITS) {
/* Shift within limbs. */
mpn_rshift(r->data, r->data, r->limbs, bits % GMP_NUMB_BITS);
}
if (bits >= GMP_NUMB_BITS) {
int i;
/* Shift full limbs. */
for (i = 0; i < r->limbs; i++) {
int index = i + (bits / GMP_NUMB_BITS);
@ -253,7 +253,7 @@ static void secp256k1_num_shift(secp256k1_num_t *r, int bits) {
}
}
static void secp256k1_num_negate(secp256k1_num_t *r) {
static void secp256k1_num_negate(secp256k1_num *r) {
r->neg ^= 1;
}

@ -0,0 +1,104 @@
/**********************************************************************
* Copyright (c) 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_SCALAR_
#define _SECP256K1_SCALAR_
#include "num.h"
#if defined HAVE_CONFIG_H
#include "libsecp256k1-config.h"
#endif
#if defined(USE_SCALAR_4X64)
#include "scalar_4x64.h"
#elif defined(USE_SCALAR_8X32)
#include "scalar_8x32.h"
#else
#error "Please select scalar implementation"
#endif
/** Clear a scalar to prevent the leak of sensitive data. */
static void secp256k1_scalar_clear(secp256k1_scalar *r);
/** Access bits from a scalar. All requested bits must belong to the same 32-bit limb. */
static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar *a, unsigned int offset, unsigned int count);
/** Access bits from a scalar. Not constant time. */
static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar *a, unsigned int offset, unsigned int count);
/** Set a scalar from a big endian byte array. */
static void secp256k1_scalar_set_b32(secp256k1_scalar *r, const unsigned char *bin, int *overflow);
/** Set a scalar to an unsigned integer. */
static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v);
/** Convert a scalar to a byte array. */
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar* a);
/** Add two scalars together (modulo the group order). Returns whether it overflowed. */
static int secp256k1_scalar_add(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b);
/** Conditionally add a power of two to a scalar. The result is not allowed to overflow. */
static void secp256k1_scalar_cadd_bit(secp256k1_scalar *r, unsigned int bit, int flag);
/** Multiply two scalars (modulo the group order). */
static void secp256k1_scalar_mul(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b);
/** Shift a scalar right by some amount strictly between 0 and 16, returning
* the low bits that were shifted off */
static int secp256k1_scalar_shr_int(secp256k1_scalar *r, int n);
/** Compute the square of a scalar (modulo the group order). */
static void secp256k1_scalar_sqr(secp256k1_scalar *r, const secp256k1_scalar *a);
/** Compute the inverse of a scalar (modulo the group order). */
static void secp256k1_scalar_inverse(secp256k1_scalar *r, const secp256k1_scalar *a);
/** Compute the inverse of a scalar (modulo the group order), without constant-time guarantee. */
static void secp256k1_scalar_inverse_var(secp256k1_scalar *r, const secp256k1_scalar *a);
/** Compute the complement of a scalar (modulo the group order). */
static void secp256k1_scalar_negate(secp256k1_scalar *r, const secp256k1_scalar *a);
/** Check whether a scalar equals zero. */
static int secp256k1_scalar_is_zero(const secp256k1_scalar *a);
/** Check whether a scalar equals one. */
static int secp256k1_scalar_is_one(const secp256k1_scalar *a);
/** Check whether a scalar, considered as an nonnegative integer, is even. */
static int secp256k1_scalar_is_even(const secp256k1_scalar *a);
/** Check whether a scalar is higher than the group order divided by 2. */
static int secp256k1_scalar_is_high(const secp256k1_scalar *a);
/** Conditionally negate a number, in constant time.
* Returns -1 if the number was negated, 1 otherwise */
static int secp256k1_scalar_cond_negate(secp256k1_scalar *a, int flag);
#ifndef USE_NUM_NONE
/** Convert a scalar to a number. */
static void secp256k1_scalar_get_num(secp256k1_num *r, const secp256k1_scalar *a);
/** Get the order of the group as a number. */
static void secp256k1_scalar_order_get_num(secp256k1_num *r);
#endif
/** Compare two scalars. */
static int secp256k1_scalar_eq(const secp256k1_scalar *a, const secp256k1_scalar *b);
#ifdef USE_ENDOMORPHISM
/** Find r1 and r2 such that r1+r2*2^128 = a. */
static void secp256k1_scalar_split_128(secp256k1_scalar *r1, secp256k1_scalar *r2, const secp256k1_scalar *a);
/** Find r1 and r2 such that r1+r2*lambda = a, and r1 and r2 are maximum 128 bits long (see secp256k1_gej_mul_lambda). */
static void secp256k1_scalar_split_lambda(secp256k1_scalar *r1, secp256k1_scalar *r2, const secp256k1_scalar *a);
#endif
/** Multiply a and b (without taking the modulus!), divide by 2**shift, and round to the nearest integer. Shift must be at least 256. */
static void secp256k1_scalar_mul_shift_var(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b, unsigned int shift);
#endif

@ -12,7 +12,7 @@
/** A scalar modulo the group order of the secp256k1 curve. */
typedef struct {
uint64_t d[4];
} secp256k1_scalar_t;
} secp256k1_scalar;
#define SECP256K1_SCALAR_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{((uint64_t)(d1)) << 32 | (d0), ((uint64_t)(d3)) << 32 | (d2), ((uint64_t)(d5)) << 32 | (d4), ((uint64_t)(d7)) << 32 | (d6)}}

@ -24,26 +24,26 @@
#define SECP256K1_N_H_2 ((uint64_t)0xFFFFFFFFFFFFFFFFULL)
#define SECP256K1_N_H_3 ((uint64_t)0x7FFFFFFFFFFFFFFFULL)
SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar_t *r) {
SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) {
r->d[0] = 0;
r->d[1] = 0;
r->d[2] = 0;
r->d[3] = 0;
}
SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar_t *r, unsigned int v) {
SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v) {
r->d[0] = v;
r->d[1] = 0;
r->d[2] = 0;
r->d[3] = 0;
}
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count) {
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar *a, unsigned int offset, unsigned int count) {
VERIFY_CHECK((offset + count - 1) >> 6 == offset >> 6);
return (a->d[offset >> 6] >> (offset & 0x3F)) & ((((uint64_t)1) << count) - 1);
}
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count) {
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar *a, unsigned int offset, unsigned int count) {
VERIFY_CHECK(count < 32);
VERIFY_CHECK(offset + count <= 256);
if ((offset + count - 1) >> 6 == offset >> 6) {
@ -54,7 +54,7 @@ SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256
}
}
SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scalar *a) {
int yes = 0;
int no = 0;
no |= (a->d[3] < SECP256K1_N_3); /* No need for a > check. */
@ -66,7 +66,7 @@ SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scal
return yes;
}
SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, unsigned int overflow) {
SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar *r, unsigned int overflow) {
uint128_t t;
VERIFY_CHECK(overflow <= 1);
t = (uint128_t)r->d[0] + overflow * SECP256K1_N_C_0;
@ -80,7 +80,7 @@ SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, unsig
return overflow;
}
static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static int secp256k1_scalar_add(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b) {
int overflow;
uint128_t t = (uint128_t)a->d[0] + b->d[0];
r->d[0] = t & 0xFFFFFFFFFFFFFFFFULL; t >>= 64;
@ -96,9 +96,10 @@ static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t
return overflow;
}
static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
static void secp256k1_scalar_cadd_bit(secp256k1_scalar *r, unsigned int bit, int flag) {
uint128_t t;
VERIFY_CHECK(bit < 256);
bit += ((uint32_t) flag - 1) & 0x100; /* forcing (bit >> 6) > 3 makes this a noop */
t = (uint128_t)r->d[0] + (((uint64_t)((bit >> 6) == 0)) << (bit & 0x3F));
r->d[0] = t & 0xFFFFFFFFFFFFFFFFULL; t >>= 64;
t += (uint128_t)r->d[1] + (((uint64_t)((bit >> 6) == 1)) << (bit & 0x3F));
@ -113,7 +114,7 @@ static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
#endif
}
static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char *b32, int *overflow) {
static void secp256k1_scalar_set_b32(secp256k1_scalar *r, const unsigned char *b32, int *overflow) {
int over;
r->d[0] = (uint64_t)b32[31] | (uint64_t)b32[30] << 8 | (uint64_t)b32[29] << 16 | (uint64_t)b32[28] << 24 | (uint64_t)b32[27] << 32 | (uint64_t)b32[26] << 40 | (uint64_t)b32[25] << 48 | (uint64_t)b32[24] << 56;
r->d[1] = (uint64_t)b32[23] | (uint64_t)b32[22] << 8 | (uint64_t)b32[21] << 16 | (uint64_t)b32[20] << 24 | (uint64_t)b32[19] << 32 | (uint64_t)b32[18] << 40 | (uint64_t)b32[17] << 48 | (uint64_t)b32[16] << 56;
@ -125,18 +126,18 @@ static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char
}
}
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar_t* a) {
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar* a) {
bin[0] = a->d[3] >> 56; bin[1] = a->d[3] >> 48; bin[2] = a->d[3] >> 40; bin[3] = a->d[3] >> 32; bin[4] = a->d[3] >> 24; bin[5] = a->d[3] >> 16; bin[6] = a->d[3] >> 8; bin[7] = a->d[3];
bin[8] = a->d[2] >> 56; bin[9] = a->d[2] >> 48; bin[10] = a->d[2] >> 40; bin[11] = a->d[2] >> 32; bin[12] = a->d[2] >> 24; bin[13] = a->d[2] >> 16; bin[14] = a->d[2] >> 8; bin[15] = a->d[2];
bin[16] = a->d[1] >> 56; bin[17] = a->d[1] >> 48; bin[18] = a->d[1] >> 40; bin[19] = a->d[1] >> 32; bin[20] = a->d[1] >> 24; bin[21] = a->d[1] >> 16; bin[22] = a->d[1] >> 8; bin[23] = a->d[1];
bin[24] = a->d[0] >> 56; bin[25] = a->d[0] >> 48; bin[26] = a->d[0] >> 40; bin[27] = a->d[0] >> 32; bin[28] = a->d[0] >> 24; bin[29] = a->d[0] >> 16; bin[30] = a->d[0] >> 8; bin[31] = a->d[0];
}
SECP256K1_INLINE static int secp256k1_scalar_is_zero(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_is_zero(const secp256k1_scalar *a) {
return (a->d[0] | a->d[1] | a->d[2] | a->d[3]) == 0;
}
static void secp256k1_scalar_negate(secp256k1_scalar_t *r, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_negate(secp256k1_scalar *r, const secp256k1_scalar *a) {
uint64_t nonzero = 0xFFFFFFFFFFFFFFFFULL * (secp256k1_scalar_is_zero(a) == 0);
uint128_t t = (uint128_t)(~a->d[0]) + SECP256K1_N_0 + 1;
r->d[0] = t & nonzero; t >>= 64;
@ -148,11 +149,11 @@ static void secp256k1_scalar_negate(secp256k1_scalar_t *r, const secp256k1_scala
r->d[3] = t & nonzero;
}
SECP256K1_INLINE static int secp256k1_scalar_is_one(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_is_one(const secp256k1_scalar *a) {
return ((a->d[0] ^ 1) | a->d[1] | a->d[2] | a->d[3]) == 0;
}
static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
static int secp256k1_scalar_is_high(const secp256k1_scalar *a) {
int yes = 0;
int no = 0;
no |= (a->d[3] < SECP256K1_N_H_3);
@ -164,6 +165,22 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
return yes;
}
static int secp256k1_scalar_cond_negate(secp256k1_scalar *r, int flag) {
/* If we are flag = 0, mask = 00...00 and this is a no-op;
* if we are flag = 1, mask = 11...11 and this is identical to secp256k1_scalar_negate */
uint64_t mask = !flag - 1;
uint64_t nonzero = (secp256k1_scalar_is_zero(r) != 0) - 1;
uint128_t t = (uint128_t)(r->d[0] ^ mask) + ((SECP256K1_N_0 + 1) & mask);
r->d[0] = t & nonzero; t >>= 64;
t += (uint128_t)(r->d[1] ^ mask) + (SECP256K1_N_1 & mask);
r->d[1] = t & nonzero; t >>= 64;
t += (uint128_t)(r->d[2] ^ mask) + (SECP256K1_N_2 & mask);
r->d[2] = t & nonzero; t >>= 64;
t += (uint128_t)(r->d[3] ^ mask) + (SECP256K1_N_3 & mask);
r->d[3] = t & nonzero;
return 2 * (mask == 0) - 1;
}
/* Inspired by the macros in OpenSSL's crypto/bn/asm/x86_64-gcc.c. */
/** Add a*b to the number defined by (c0,c1,c2). c2 must never overflow. */
@ -250,7 +267,7 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
VERIFY_CHECK(c2 == 0); \
}
static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint64_t *l) {
static void secp256k1_scalar_reduce_512(secp256k1_scalar *r, const uint64_t *l) {
#ifdef USE_ASM_X86_64
/* Reduce 512 bits into 385. */
uint64_t m0, m1, m2, m3, m4, m5, m6;
@ -559,7 +576,7 @@ static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint64_t *l
secp256k1_scalar_reduce(r, c + secp256k1_scalar_check_overflow(r));
}
static void secp256k1_scalar_mul_512(uint64_t l[8], const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static void secp256k1_scalar_mul_512(uint64_t l[8], const secp256k1_scalar *a, const secp256k1_scalar *b) {
#ifdef USE_ASM_X86_64
const uint64_t *pb = b->d;
__asm__ __volatile__(
@ -721,12 +738,12 @@ static void secp256k1_scalar_mul_512(uint64_t l[8], const secp256k1_scalar_t *a,
extract(l[5]);
muladd_fast(a->d[3], b->d[3]);
extract_fast(l[6]);
VERIFY_CHECK(c1 <= 0);
VERIFY_CHECK(c1 == 0);
l[7] = c0;
#endif
}
static void secp256k1_scalar_sqr_512(uint64_t l[8], const secp256k1_scalar_t *a) {
static void secp256k1_scalar_sqr_512(uint64_t l[8], const secp256k1_scalar *a) {
#ifdef USE_ASM_X86_64
__asm__ __volatile__(
/* Preload */
@ -871,19 +888,31 @@ static void secp256k1_scalar_sqr_512(uint64_t l[8], const secp256k1_scalar_t *a)
#undef extract
#undef extract_fast
static void secp256k1_scalar_mul(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static void secp256k1_scalar_mul(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b) {
uint64_t l[8];
secp256k1_scalar_mul_512(l, a, b);
secp256k1_scalar_reduce_512(r, l);
}
static void secp256k1_scalar_sqr(secp256k1_scalar_t *r, const secp256k1_scalar_t *a) {
static int secp256k1_scalar_shr_int(secp256k1_scalar *r, int n) {
int ret;
VERIFY_CHECK(n > 0);
VERIFY_CHECK(n < 16);
ret = r->d[0] & ((1 << n) - 1);
r->d[0] = (r->d[0] >> n) + (r->d[1] << (64 - n));
r->d[1] = (r->d[1] >> n) + (r->d[2] << (64 - n));
r->d[2] = (r->d[2] >> n) + (r->d[3] << (64 - n));
r->d[3] = (r->d[3] >> n);
return ret;
}
static void secp256k1_scalar_sqr(secp256k1_scalar *r, const secp256k1_scalar *a) {
uint64_t l[8];
secp256k1_scalar_sqr_512(l, a);
secp256k1_scalar_reduce_512(r, l);
}
static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_split_128(secp256k1_scalar *r1, secp256k1_scalar *r2, const secp256k1_scalar *a) {
r1->d[0] = a->d[0];
r1->d[1] = a->d[1];
r1->d[2] = 0;
@ -894,11 +923,11 @@ static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_
r2->d[3] = 0;
}
SECP256K1_INLINE static int secp256k1_scalar_eq(const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
SECP256K1_INLINE static int secp256k1_scalar_eq(const secp256k1_scalar *a, const secp256k1_scalar *b) {
return ((a->d[0] ^ b->d[0]) | (a->d[1] ^ b->d[1]) | (a->d[2] ^ b->d[2]) | (a->d[3] ^ b->d[3])) == 0;
}
SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b, unsigned int shift) {
SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b, unsigned int shift) {
uint64_t l[8];
unsigned int shiftlimbs;
unsigned int shiftlow;
@ -912,9 +941,7 @@ SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *
r->d[1] = shift < 448 ? (l[1 + shiftlimbs] >> shiftlow | (shift < 384 && shiftlow ? (l[2 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[2] = shift < 384 ? (l[2 + shiftlimbs] >> shiftlow | (shift < 320 && shiftlow ? (l[3 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[3] = shift < 320 ? (l[3 + shiftlimbs] >> shiftlow) : 0;
if ((l[(shift - 1) >> 6] >> ((shift - 1) & 0x3f)) & 1) {
secp256k1_scalar_add_bit(r, 0);
}
secp256k1_scalar_cadd_bit(r, 0, (l[(shift - 1) >> 6] >> ((shift - 1) & 0x3f)) & 1);
}
#endif

@ -12,7 +12,7 @@
/** A scalar modulo the group order of the secp256k1 curve. */
typedef struct {
uint32_t d[8];
} secp256k1_scalar_t;
} secp256k1_scalar;
#define SECP256K1_SCALAR_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{(d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7)}}

@ -34,7 +34,7 @@
#define SECP256K1_N_H_6 ((uint32_t)0xFFFFFFFFUL)
#define SECP256K1_N_H_7 ((uint32_t)0x7FFFFFFFUL)
SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar_t *r) {
SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) {
r->d[0] = 0;
r->d[1] = 0;
r->d[2] = 0;
@ -45,7 +45,7 @@ SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar_t *r) {
r->d[7] = 0;
}
SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar_t *r, unsigned int v) {
SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v) {
r->d[0] = v;
r->d[1] = 0;
r->d[2] = 0;
@ -56,12 +56,12 @@ SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar_t *r, uns
r->d[7] = 0;
}
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count) {
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar *a, unsigned int offset, unsigned int count) {
VERIFY_CHECK((offset + count - 1) >> 5 == offset >> 5);
return (a->d[offset >> 5] >> (offset & 0x1F)) & ((1 << count) - 1);
}
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count) {
SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar *a, unsigned int offset, unsigned int count) {
VERIFY_CHECK(count < 32);
VERIFY_CHECK(offset + count <= 256);
if ((offset + count - 1) >> 5 == offset >> 5) {
@ -72,7 +72,7 @@ SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits_var(const secp256
}
}
SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scalar *a) {
int yes = 0;
int no = 0;
no |= (a->d[7] < SECP256K1_N_7); /* No need for a > check. */
@ -90,7 +90,7 @@ SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scal
return yes;
}
SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, uint32_t overflow) {
SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar *r, uint32_t overflow) {
uint64_t t;
VERIFY_CHECK(overflow <= 1);
t = (uint64_t)r->d[0] + overflow * SECP256K1_N_C_0;
@ -112,7 +112,7 @@ SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, uint3
return overflow;
}
static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static int secp256k1_scalar_add(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b) {
int overflow;
uint64_t t = (uint64_t)a->d[0] + b->d[0];
r->d[0] = t & 0xFFFFFFFFULL; t >>= 32;
@ -136,9 +136,10 @@ static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t
return overflow;
}
static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
static void secp256k1_scalar_cadd_bit(secp256k1_scalar *r, unsigned int bit, int flag) {
uint64_t t;
VERIFY_CHECK(bit < 256);
bit += ((uint32_t) flag - 1) & 0x100; /* forcing (bit >> 5) > 7 makes this a noop */
t = (uint64_t)r->d[0] + (((uint32_t)((bit >> 5) == 0)) << (bit & 0x1F));
r->d[0] = t & 0xFFFFFFFFULL; t >>= 32;
t += (uint64_t)r->d[1] + (((uint32_t)((bit >> 5) == 1)) << (bit & 0x1F));
@ -161,7 +162,7 @@ static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
#endif
}
static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char *b32, int *overflow) {
static void secp256k1_scalar_set_b32(secp256k1_scalar *r, const unsigned char *b32, int *overflow) {
int over;
r->d[0] = (uint32_t)b32[31] | (uint32_t)b32[30] << 8 | (uint32_t)b32[29] << 16 | (uint32_t)b32[28] << 24;
r->d[1] = (uint32_t)b32[27] | (uint32_t)b32[26] << 8 | (uint32_t)b32[25] << 16 | (uint32_t)b32[24] << 24;
@ -177,7 +178,7 @@ static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char
}
}
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar_t* a) {
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar* a) {
bin[0] = a->d[7] >> 24; bin[1] = a->d[7] >> 16; bin[2] = a->d[7] >> 8; bin[3] = a->d[7];
bin[4] = a->d[6] >> 24; bin[5] = a->d[6] >> 16; bin[6] = a->d[6] >> 8; bin[7] = a->d[6];
bin[8] = a->d[5] >> 24; bin[9] = a->d[5] >> 16; bin[10] = a->d[5] >> 8; bin[11] = a->d[5];
@ -188,11 +189,11 @@ static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar_
bin[28] = a->d[0] >> 24; bin[29] = a->d[0] >> 16; bin[30] = a->d[0] >> 8; bin[31] = a->d[0];
}
SECP256K1_INLINE static int secp256k1_scalar_is_zero(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_is_zero(const secp256k1_scalar *a) {
return (a->d[0] | a->d[1] | a->d[2] | a->d[3] | a->d[4] | a->d[5] | a->d[6] | a->d[7]) == 0;
}
static void secp256k1_scalar_negate(secp256k1_scalar_t *r, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_negate(secp256k1_scalar *r, const secp256k1_scalar *a) {
uint32_t nonzero = 0xFFFFFFFFUL * (secp256k1_scalar_is_zero(a) == 0);
uint64_t t = (uint64_t)(~a->d[0]) + SECP256K1_N_0 + 1;
r->d[0] = t & nonzero; t >>= 32;
@ -212,11 +213,11 @@ static void secp256k1_scalar_negate(secp256k1_scalar_t *r, const secp256k1_scala
r->d[7] = t & nonzero;
}
SECP256K1_INLINE static int secp256k1_scalar_is_one(const secp256k1_scalar_t *a) {
SECP256K1_INLINE static int secp256k1_scalar_is_one(const secp256k1_scalar *a) {
return ((a->d[0] ^ 1) | a->d[1] | a->d[2] | a->d[3] | a->d[4] | a->d[5] | a->d[6] | a->d[7]) == 0;
}
static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
static int secp256k1_scalar_is_high(const secp256k1_scalar *a) {
int yes = 0;
int no = 0;
no |= (a->d[7] < SECP256K1_N_H_7);
@ -234,6 +235,31 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
return yes;
}
static int secp256k1_scalar_cond_negate(secp256k1_scalar *r, int flag) {
/* If we are flag = 0, mask = 00...00 and this is a no-op;
* if we are flag = 1, mask = 11...11 and this is identical to secp256k1_scalar_negate */
uint32_t mask = !flag - 1;
uint32_t nonzero = 0xFFFFFFFFUL * (secp256k1_scalar_is_zero(r) == 0);
uint64_t t = (uint64_t)(r->d[0] ^ mask) + ((SECP256K1_N_0 + 1) & mask);
r->d[0] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[1] ^ mask) + (SECP256K1_N_1 & mask);
r->d[1] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[2] ^ mask) + (SECP256K1_N_2 & mask);
r->d[2] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[3] ^ mask) + (SECP256K1_N_3 & mask);
r->d[3] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[4] ^ mask) + (SECP256K1_N_4 & mask);
r->d[4] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[5] ^ mask) + (SECP256K1_N_5 & mask);
r->d[5] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[6] ^ mask) + (SECP256K1_N_6 & mask);
r->d[6] = t & nonzero; t >>= 32;
t += (uint64_t)(r->d[7] ^ mask) + (SECP256K1_N_7 & mask);
r->d[7] = t & nonzero;
return 2 * (mask == 0) - 1;
}
/* Inspired by the macros in OpenSSL's crypto/bn/asm/x86_64-gcc.c. */
/** Add a*b to the number defined by (c0,c1,c2). c2 must never overflow. */
@ -320,7 +346,7 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
VERIFY_CHECK(c2 == 0); \
}
static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint32_t *l) {
static void secp256k1_scalar_reduce_512(secp256k1_scalar *r, const uint32_t *l) {
uint64_t c;
uint32_t n0 = l[8], n1 = l[9], n2 = l[10], n3 = l[11], n4 = l[12], n5 = l[13], n6 = l[14], n7 = l[15];
uint32_t m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12;
@ -462,7 +488,7 @@ static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint32_t *l
secp256k1_scalar_reduce(r, c + secp256k1_scalar_check_overflow(r));
}
static void secp256k1_scalar_mul_512(uint32_t *l, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static void secp256k1_scalar_mul_512(uint32_t *l, const secp256k1_scalar *a, const secp256k1_scalar *b) {
/* 96 bit accumulator. */
uint32_t c0 = 0, c1 = 0, c2 = 0;
@ -550,7 +576,7 @@ static void secp256k1_scalar_mul_512(uint32_t *l, const secp256k1_scalar_t *a, c
l[15] = c0;
}
static void secp256k1_scalar_sqr_512(uint32_t *l, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_sqr_512(uint32_t *l, const secp256k1_scalar *a) {
/* 96 bit accumulator. */
uint32_t c0 = 0, c1 = 0, c2 = 0;
@ -618,20 +644,36 @@ static void secp256k1_scalar_sqr_512(uint32_t *l, const secp256k1_scalar_t *a) {
#undef extract
#undef extract_fast
static void secp256k1_scalar_mul(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static void secp256k1_scalar_mul(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b) {
uint32_t l[16];
secp256k1_scalar_mul_512(l, a, b);
secp256k1_scalar_reduce_512(r, l);
}
static void secp256k1_scalar_sqr(secp256k1_scalar_t *r, const secp256k1_scalar_t *a) {
static int secp256k1_scalar_shr_int(secp256k1_scalar *r, int n) {
int ret;
VERIFY_CHECK(n > 0);
VERIFY_CHECK(n < 16);
ret = r->d[0] & ((1 << n) - 1);
r->d[0] = (r->d[0] >> n) + (r->d[1] << (32 - n));
r->d[1] = (r->d[1] >> n) + (r->d[2] << (32 - n));
r->d[2] = (r->d[2] >> n) + (r->d[3] << (32 - n));
r->d[3] = (r->d[3] >> n) + (r->d[4] << (32 - n));
r->d[4] = (r->d[4] >> n) + (r->d[5] << (32 - n));
r->d[5] = (r->d[5] >> n) + (r->d[6] << (32 - n));
r->d[6] = (r->d[6] >> n) + (r->d[7] << (32 - n));
r->d[7] = (r->d[7] >> n);
return ret;
}
static void secp256k1_scalar_sqr(secp256k1_scalar *r, const secp256k1_scalar *a) {
uint32_t l[16];
secp256k1_scalar_sqr_512(l, a);
secp256k1_scalar_reduce_512(r, l);
}
#ifdef USE_ENDOMORPHISM
static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_split_128(secp256k1_scalar *r1, secp256k1_scalar *r2, const secp256k1_scalar *a) {
r1->d[0] = a->d[0];
r1->d[1] = a->d[1];
r1->d[2] = a->d[2];
@ -651,11 +693,11 @@ static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_
}
#endif
SECP256K1_INLINE static int secp256k1_scalar_eq(const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
SECP256K1_INLINE static int secp256k1_scalar_eq(const secp256k1_scalar *a, const secp256k1_scalar *b) {
return ((a->d[0] ^ b->d[0]) | (a->d[1] ^ b->d[1]) | (a->d[2] ^ b->d[2]) | (a->d[3] ^ b->d[3]) | (a->d[4] ^ b->d[4]) | (a->d[5] ^ b->d[5]) | (a->d[6] ^ b->d[6]) | (a->d[7] ^ b->d[7])) == 0;
}
SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b, unsigned int shift) {
SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar *r, const secp256k1_scalar *a, const secp256k1_scalar *b, unsigned int shift) {
uint32_t l[16];
unsigned int shiftlimbs;
unsigned int shiftlow;
@ -673,9 +715,7 @@ SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *
r->d[5] = shift < 352 ? (l[5 + shiftlimbs] >> shiftlow | (shift < 320 && shiftlow ? (l[6 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[6] = shift < 320 ? (l[6 + shiftlimbs] >> shiftlow | (shift < 288 && shiftlow ? (l[7 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[7] = shift < 288 ? (l[7 + shiftlimbs] >> shiftlow) : 0;
if ((l[(shift - 1) >> 5] >> ((shift - 1) & 0x1f)) & 1) {
secp256k1_scalar_add_bit(r, 0);
}
secp256k1_scalar_cadd_bit(r, 0, (l[(shift - 1) >> 5] >> ((shift - 1) & 0x1f)) & 1);
}
#endif

@ -25,14 +25,14 @@
#endif
#ifndef USE_NUM_NONE
static void secp256k1_scalar_get_num(secp256k1_num_t *r, const secp256k1_scalar_t *a) {
static void secp256k1_scalar_get_num(secp256k1_num *r, const secp256k1_scalar *a) {
unsigned char c[32];
secp256k1_scalar_get_b32(c, a);
secp256k1_num_set_bin(r, c, 32);
}
/** secp256k1 curve order, see secp256k1_ecdsa_const_order_as_fe in ecdsa_impl.h */
static void secp256k1_scalar_order_get_num(secp256k1_num_t *r) {
static void secp256k1_scalar_order_get_num(secp256k1_num *r) {
static const unsigned char order[32] = {
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFE,
@ -43,11 +43,11 @@ static void secp256k1_scalar_order_get_num(secp256k1_num_t *r) {
}
#endif
static void secp256k1_scalar_inverse(secp256k1_scalar_t *r, const secp256k1_scalar_t *x) {
secp256k1_scalar_t *t;
static void secp256k1_scalar_inverse(secp256k1_scalar *r, const secp256k1_scalar *x) {
secp256k1_scalar *t;
int i;
/* First compute x ^ (2^N - 1) for some values of N. */
secp256k1_scalar_t x2, x3, x4, x6, x7, x8, x15, x30, x60, x120, x127;
secp256k1_scalar x2, x3, x4, x6, x7, x8, x15, x30, x60, x120, x127;
secp256k1_scalar_sqr(&x2, x);
secp256k1_scalar_mul(&x2, &x2, x);
@ -234,18 +234,27 @@ static void secp256k1_scalar_inverse(secp256k1_scalar_t *r, const secp256k1_scal
secp256k1_scalar_mul(r, t, &x6); /* 111111 */
}
static void secp256k1_scalar_inverse_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *x) {
SECP256K1_INLINE static int secp256k1_scalar_is_even(const secp256k1_scalar *a) {
/* d[0] is present and is the lowest word for all representations */
return !(a->d[0] & 1);
}
static void secp256k1_scalar_inverse_var(secp256k1_scalar *r, const secp256k1_scalar *x) {
#if defined(USE_SCALAR_INV_BUILTIN)
secp256k1_scalar_inverse(r, x);
#elif defined(USE_SCALAR_INV_NUM)
unsigned char b[32];
secp256k1_num_t n, m;
secp256k1_scalar_get_b32(b, x);
secp256k1_num n, m;
secp256k1_scalar t = *x;
secp256k1_scalar_get_b32(b, &t);
secp256k1_num_set_bin(&n, b, 32);
secp256k1_scalar_order_get_num(&m);
secp256k1_num_mod_inverse(&n, &n, &m);
secp256k1_num_get_bin(b, 32, &n);
secp256k1_scalar_set_b32(r, b, NULL);
/* Verify that the inverse was computed correctly, without GMP code. */
secp256k1_scalar_mul(&t, &t, r);
CHECK(secp256k1_scalar_is_one(&t));
#else
#error "Please select scalar inverse implementation"
#endif
@ -290,30 +299,31 @@ static void secp256k1_scalar_inverse_var(secp256k1_scalar_t *r, const secp256k1_
* The function below splits a in r1 and r2, such that r1 + lambda * r2 == a (mod order).
*/
static void secp256k1_scalar_split_lambda_var(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a) {
secp256k1_scalar_t c1, c2;
static const secp256k1_scalar_t minus_lambda = SECP256K1_SCALAR_CONST(
static void secp256k1_scalar_split_lambda(secp256k1_scalar *r1, secp256k1_scalar *r2, const secp256k1_scalar *a) {
secp256k1_scalar c1, c2;
static const secp256k1_scalar minus_lambda = SECP256K1_SCALAR_CONST(
0xAC9C52B3UL, 0x3FA3CF1FUL, 0x5AD9E3FDUL, 0x77ED9BA4UL,
0xA880B9FCUL, 0x8EC739C2UL, 0xE0CFC810UL, 0xB51283CFUL
);
static const secp256k1_scalar_t minus_b1 = SECP256K1_SCALAR_CONST(
static const secp256k1_scalar minus_b1 = SECP256K1_SCALAR_CONST(
0x00000000UL, 0x00000000UL, 0x00000000UL, 0x00000000UL,
0xE4437ED6UL, 0x010E8828UL, 0x6F547FA9UL, 0x0ABFE4C3UL
);
static const secp256k1_scalar_t minus_b2 = SECP256K1_SCALAR_CONST(
static const secp256k1_scalar minus_b2 = SECP256K1_SCALAR_CONST(
0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFEUL,
0x8A280AC5UL, 0x0774346DUL, 0xD765CDA8UL, 0x3DB1562CUL
);
static const secp256k1_scalar_t g1 = SECP256K1_SCALAR_CONST(
static const secp256k1_scalar g1 = SECP256K1_SCALAR_CONST(
0x00000000UL, 0x00000000UL, 0x00000000UL, 0x00003086UL,
0xD221A7D4UL, 0x6BCDE86CUL, 0x90E49284UL, 0xEB153DABUL
);
static const secp256k1_scalar_t g2 = SECP256K1_SCALAR_CONST(
static const secp256k1_scalar g2 = SECP256K1_SCALAR_CONST(
0x00000000UL, 0x00000000UL, 0x00000000UL, 0x0000E443UL,
0x7ED6010EUL, 0x88286F54UL, 0x7FA90ABFUL, 0xE4C42212UL
);
VERIFY_CHECK(r1 != a);
VERIFY_CHECK(r2 != a);
/* these _var calls are constant time since the shift amount is constant */
secp256k1_scalar_mul_shift_var(&c1, a, &g1, 272);
secp256k1_scalar_mul_shift_var(&c2, a, &g2, 272);
secp256k1_scalar_mul(&c1, &c1, &minus_b1);

@ -0,0 +1,513 @@
/**********************************************************************
* Copyright (c) 2013-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#define SECP256K1_BUILD (1)
#include "include/secp256k1.h"
#include "util.h"
#include "num_impl.h"
#include "field_impl.h"
#include "scalar_impl.h"
#include "group_impl.h"
#include "ecmult_impl.h"
#include "ecmult_const_impl.h"
#include "ecmult_gen_impl.h"
#include "ecdsa_impl.h"
#include "eckey_impl.h"
#include "hash_impl.h"
#define ARG_CHECK(cond) do { \
if (EXPECT(!(cond), 0)) { \
secp256k1_callback_call(&ctx->illegal_callback, #cond); \
return 0; \
} \
} while(0)
static void default_illegal_callback_fn(const char* str, void* data) {
(void)data;
fprintf(stderr, "[libsecp256k1] illegal argument: %s\n", str);
abort();
}
static const secp256k1_callback default_illegal_callback = {
default_illegal_callback_fn,
NULL
};
static void default_error_callback_fn(const char* str, void* data) {
(void)data;
fprintf(stderr, "[libsecp256k1] internal consistency check failed: %s\n", str);
abort();
}
static const secp256k1_callback default_error_callback = {
default_error_callback_fn,
NULL
};
struct secp256k1_context_struct {
secp256k1_ecmult_context ecmult_ctx;
secp256k1_ecmult_gen_context ecmult_gen_ctx;
secp256k1_callback illegal_callback;
secp256k1_callback error_callback;
};
secp256k1_context* secp256k1_context_create(unsigned int flags) {
secp256k1_context* ret = (secp256k1_context*)checked_malloc(&default_error_callback, sizeof(secp256k1_context));
ret->illegal_callback = default_illegal_callback;
ret->error_callback = default_error_callback;
secp256k1_ecmult_context_init(&ret->ecmult_ctx);
secp256k1_ecmult_gen_context_init(&ret->ecmult_gen_ctx);
if (flags & SECP256K1_CONTEXT_SIGN) {
secp256k1_ecmult_gen_context_build(&ret->ecmult_gen_ctx, &ret->error_callback);
}
if (flags & SECP256K1_CONTEXT_VERIFY) {
secp256k1_ecmult_context_build(&ret->ecmult_ctx, &ret->error_callback);
}
return ret;
}
secp256k1_context* secp256k1_context_clone(const secp256k1_context* ctx) {
secp256k1_context* ret = (secp256k1_context*)checked_malloc(&ctx->error_callback, sizeof(secp256k1_context));
ret->illegal_callback = ctx->illegal_callback;
ret->error_callback = ctx->error_callback;
secp256k1_ecmult_context_clone(&ret->ecmult_ctx, &ctx->ecmult_ctx, &ctx->error_callback);
secp256k1_ecmult_gen_context_clone(&ret->ecmult_gen_ctx, &ctx->ecmult_gen_ctx, &ctx->error_callback);
return ret;
}
void secp256k1_context_destroy(secp256k1_context* ctx) {
if (ctx != NULL) {
secp256k1_ecmult_context_clear(&ctx->ecmult_ctx);
secp256k1_ecmult_gen_context_clear(&ctx->ecmult_gen_ctx);
free(ctx);
}
}
void secp256k1_context_set_illegal_callback(secp256k1_context* ctx, void (*fun)(const char* message, void* data), const void* data) {
if (fun == NULL) {
fun = default_illegal_callback_fn;
}
ctx->illegal_callback.fn = fun;
ctx->illegal_callback.data = data;
}
void secp256k1_context_set_error_callback(secp256k1_context* ctx, void (*fun)(const char* message, void* data), const void* data) {
if (fun == NULL) {
fun = default_error_callback_fn;
}
ctx->error_callback.fn = fun;
ctx->error_callback.data = data;
}
static int secp256k1_pubkey_load(const secp256k1_context* ctx, secp256k1_ge* ge, const secp256k1_pubkey* pubkey) {
if (sizeof(secp256k1_ge_storage) == 64) {
/* When the secp256k1_ge_storage type is exactly 64 byte, use its
* representation inside secp256k1_pubkey, as conversion is very fast.
* Note that secp256k1_pubkey_save must use the same representation. */
secp256k1_ge_storage s;
memcpy(&s, &pubkey->data[0], 64);
secp256k1_ge_from_storage(ge, &s);
} else {
/* Otherwise, fall back to 32-byte big endian for X and Y. */
secp256k1_fe x, y;
secp256k1_fe_set_b32(&x, pubkey->data);
secp256k1_fe_set_b32(&y, pubkey->data + 32);
secp256k1_ge_set_xy(ge, &x, &y);
}
ARG_CHECK(!secp256k1_fe_is_zero(&ge->x));
return 1;
}
static void secp256k1_pubkey_save(secp256k1_pubkey* pubkey, secp256k1_ge* ge) {
if (sizeof(secp256k1_ge_storage) == 64) {
secp256k1_ge_storage s;
secp256k1_ge_to_storage(&s, ge);
memcpy(&pubkey->data[0], &s, 64);
} else {
VERIFY_CHECK(!secp256k1_ge_is_infinity(ge));
secp256k1_fe_normalize_var(&ge->x);
secp256k1_fe_normalize_var(&ge->y);
secp256k1_fe_get_b32(pubkey->data, &ge->x);
secp256k1_fe_get_b32(pubkey->data + 32, &ge->y);
}
}
int secp256k1_ec_pubkey_parse(const secp256k1_context* ctx, secp256k1_pubkey* pubkey, const unsigned char *input, size_t inputlen) {
secp256k1_ge Q;
(void)ctx;
if (!secp256k1_eckey_pubkey_parse(&Q, input, inputlen)) {
memset(pubkey, 0, sizeof(*pubkey));
return 0;
}
secp256k1_pubkey_save(pubkey, &Q);
secp256k1_ge_clear(&Q);
return 1;
}
int secp256k1_ec_pubkey_serialize(const secp256k1_context* ctx, unsigned char *output, size_t *outputlen, const secp256k1_pubkey* pubkey, unsigned int flags) {
secp256k1_ge Q;
(void)ctx;
return (secp256k1_pubkey_load(ctx, &Q, pubkey) &&
secp256k1_eckey_pubkey_serialize(&Q, output, outputlen, flags));
}
static void secp256k1_ecdsa_signature_load(const secp256k1_context* ctx, secp256k1_scalar* r, secp256k1_scalar* s, const secp256k1_ecdsa_signature* sig) {
(void)ctx;
if (sizeof(secp256k1_scalar) == 32) {
/* When the secp256k1_scalar type is exactly 32 byte, use its
* representation inside secp256k1_ecdsa_signature, as conversion is very fast.
* Note that secp256k1_ecdsa_signature_save must use the same representation. */
memcpy(r, &sig->data[0], 32);
memcpy(s, &sig->data[32], 32);
} else {
secp256k1_scalar_set_b32(r, &sig->data[0], NULL);
secp256k1_scalar_set_b32(s, &sig->data[32], NULL);
}
}
static void secp256k1_ecdsa_signature_save(secp256k1_ecdsa_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s) {
if (sizeof(secp256k1_scalar) == 32) {
memcpy(&sig->data[0], r, 32);
memcpy(&sig->data[32], s, 32);
} else {
secp256k1_scalar_get_b32(&sig->data[0], r);
secp256k1_scalar_get_b32(&sig->data[32], s);
}
}
int secp256k1_ecdsa_signature_parse_der(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const unsigned char *input, size_t inputlen) {
secp256k1_scalar r, s;
(void)ctx;
ARG_CHECK(sig != NULL);
ARG_CHECK(input != NULL);
if (secp256k1_ecdsa_sig_parse(&r, &s, input, inputlen)) {
secp256k1_ecdsa_signature_save(sig, &r, &s);
return 1;
} else {
memset(sig, 0, sizeof(*sig));
return 0;
}
}
int secp256k1_ecdsa_signature_serialize_der(const secp256k1_context* ctx, unsigned char *output, size_t *outputlen, const secp256k1_ecdsa_signature* sig) {
secp256k1_scalar r, s;
(void)ctx;
ARG_CHECK(output != NULL);
ARG_CHECK(outputlen != NULL);
ARG_CHECK(sig != NULL);
secp256k1_ecdsa_signature_load(ctx, &r, &s, sig);
return secp256k1_ecdsa_sig_serialize(output, outputlen, &r, &s);
}
int secp256k1_ecdsa_verify(const secp256k1_context* ctx, const secp256k1_ecdsa_signature *sig, const unsigned char *msg32, const secp256k1_pubkey *pubkey) {
secp256k1_ge q;
secp256k1_scalar r, s;
secp256k1_scalar m;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig != NULL);
ARG_CHECK(pubkey != NULL);
secp256k1_scalar_set_b32(&m, msg32, NULL);
secp256k1_ecdsa_signature_load(ctx, &r, &s, sig);
return (secp256k1_pubkey_load(ctx, &q, pubkey) &&
secp256k1_ecdsa_sig_verify(&ctx->ecmult_ctx, &r, &s, &q, &m));
}
static int nonce_function_rfc6979(unsigned char *nonce32, const unsigned char *msg32, const unsigned char *key32, const unsigned char *algo16, void *data, unsigned int counter) {
unsigned char keydata[112];
int keylen = 64;
secp256k1_rfc6979_hmac_sha256_t rng;
unsigned int i;
/* We feed a byte array to the PRNG as input, consisting of:
* - the private key (32 bytes) and message (32 bytes), see RFC 6979 3.2d.
* - optionally 32 extra bytes of data, see RFC 6979 3.6 Additional Data.
* - optionally 16 extra bytes with the algorithm name (the extra data bytes
* are set to zeroes when not present, while the algorithm name is).
*/
memcpy(keydata, key32, 32);
memcpy(keydata + 32, msg32, 32);
if (data != NULL) {
memcpy(keydata + 64, data, 32);
keylen = 96;
}
if (algo16 != NULL) {
memset(keydata + keylen, 0, 96 - keylen);
memcpy(keydata + 96, algo16, 16);
keylen = 112;
}
secp256k1_rfc6979_hmac_sha256_initialize(&rng, keydata, keylen);
memset(keydata, 0, sizeof(keydata));
for (i = 0; i <= counter; i++) {
secp256k1_rfc6979_hmac_sha256_generate(&rng, nonce32, 32);
}
secp256k1_rfc6979_hmac_sha256_finalize(&rng);
return 1;
}
const secp256k1_nonce_function secp256k1_nonce_function_rfc6979 = nonce_function_rfc6979;
const secp256k1_nonce_function secp256k1_nonce_function_default = nonce_function_rfc6979;
int secp256k1_ecdsa_sign(const secp256k1_context* ctx, secp256k1_ecdsa_signature *signature, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) {
secp256k1_scalar r, s;
secp256k1_scalar sec, non, msg;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(signature != NULL);
ARG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
/* Fail if the secret key is invalid. */
if (!overflow && !secp256k1_scalar_is_zero(&sec)) {
unsigned int count = 0;
secp256k1_scalar_set_b32(&msg, msg32, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, msg32, seckey, NULL, (void*)noncedata, count);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!overflow && !secp256k1_scalar_is_zero(&non)) {
if (secp256k1_ecdsa_sig_sign(&ctx->ecmult_gen_ctx, &r, &s, &sec, &msg, &non, NULL)) {
break;
}
}
count++;
}
secp256k1_scalar_clear(&msg);
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
}
if (ret) {
secp256k1_ecdsa_signature_save(signature, &r, &s);
} else {
memset(signature, 0, sizeof(*signature));
}
return ret;
}
int secp256k1_ec_seckey_verify(const secp256k1_context* ctx, const unsigned char *seckey) {
secp256k1_scalar sec;
int ret;
int overflow;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(seckey != NULL);
(void)ctx;
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
ret = !overflow && !secp256k1_scalar_is_zero(&sec);
secp256k1_scalar_clear(&sec);
return ret;
}
int secp256k1_ec_pubkey_create(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *seckey) {
secp256k1_gej pj;
secp256k1_ge p;
secp256k1_scalar sec;
int overflow;
int ret = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(pubkey != NULL);
ARG_CHECK(seckey != NULL);
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
ret = (!overflow) & (!secp256k1_scalar_is_zero(&sec));
secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &pj, &sec);
secp256k1_ge_set_gej(&p, &pj);
secp256k1_pubkey_save(pubkey, &p);
secp256k1_scalar_clear(&sec);
if (!ret) {
memset(pubkey, 0, sizeof(*pubkey));
}
return ret;
}
int secp256k1_ec_privkey_tweak_add(const secp256k1_context* ctx, unsigned char *seckey, const unsigned char *tweak) {
secp256k1_scalar term;
secp256k1_scalar sec;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(seckey != NULL);
ARG_CHECK(tweak != NULL);
(void)ctx;
secp256k1_scalar_set_b32(&term, tweak, &overflow);
secp256k1_scalar_set_b32(&sec, seckey, NULL);
ret = !overflow && secp256k1_eckey_privkey_tweak_add(&sec, &term);
if (ret) {
secp256k1_scalar_get_b32(seckey, &sec);
}
secp256k1_scalar_clear(&sec);
secp256k1_scalar_clear(&term);
return ret;
}
int secp256k1_ec_pubkey_tweak_add(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *tweak) {
secp256k1_ge p;
secp256k1_scalar term;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(pubkey != NULL);
ARG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&term, tweak, &overflow);
if (!overflow && secp256k1_pubkey_load(ctx, &p, pubkey)) {
ret = secp256k1_eckey_pubkey_tweak_add(&ctx->ecmult_ctx, &p, &term);
if (ret) {
secp256k1_pubkey_save(pubkey, &p);
} else {
memset(pubkey, 0, sizeof(*pubkey));
}
}
return ret;
}
int secp256k1_ec_privkey_tweak_mul(const secp256k1_context* ctx, unsigned char *seckey, const unsigned char *tweak) {
secp256k1_scalar factor;
secp256k1_scalar sec;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(seckey != NULL);
ARG_CHECK(tweak != NULL);
(void)ctx;
secp256k1_scalar_set_b32(&factor, tweak, &overflow);
secp256k1_scalar_set_b32(&sec, seckey, NULL);
ret = !overflow && secp256k1_eckey_privkey_tweak_mul(&sec, &factor);
if (ret) {
secp256k1_scalar_get_b32(seckey, &sec);
}
secp256k1_scalar_clear(&sec);
secp256k1_scalar_clear(&factor);
return ret;
}
int secp256k1_ec_pubkey_tweak_mul(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *tweak) {
secp256k1_ge p;
secp256k1_scalar factor;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(pubkey != NULL);
ARG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&factor, tweak, &overflow);
if (!overflow && secp256k1_pubkey_load(ctx, &p, pubkey)) {
ret = secp256k1_eckey_pubkey_tweak_mul(&ctx->ecmult_ctx, &p, &factor);
if (ret) {
secp256k1_pubkey_save(pubkey, &p);
} else {
memset(pubkey, 0, sizeof(*pubkey));
}
}
return ret;
}
int secp256k1_ec_privkey_export(const secp256k1_context* ctx, unsigned char *privkey, size_t *privkeylen, const unsigned char *seckey, unsigned int flags) {
secp256k1_scalar key;
int ret = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(seckey != NULL);
ARG_CHECK(privkey != NULL);
ARG_CHECK(privkeylen != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
secp256k1_scalar_set_b32(&key, seckey, NULL);
ret = secp256k1_eckey_privkey_serialize(&ctx->ecmult_gen_ctx, privkey, privkeylen, &key, flags);
secp256k1_scalar_clear(&key);
return ret;
}
int secp256k1_ec_privkey_import(const secp256k1_context* ctx, unsigned char *seckey, const unsigned char *privkey, size_t privkeylen) {
secp256k1_scalar key;
int ret = 0;
ARG_CHECK(seckey != NULL);
ARG_CHECK(privkey != NULL);
(void)ctx;
ret = secp256k1_eckey_privkey_parse(&key, privkey, privkeylen);
if (ret) {
secp256k1_scalar_get_b32(seckey, &key);
}
secp256k1_scalar_clear(&key);
return ret;
}
int secp256k1_context_randomize(secp256k1_context* ctx, const unsigned char *seed32) {
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
secp256k1_ecmult_gen_blind(&ctx->ecmult_gen_ctx, seed32);
return 1;
}
int secp256k1_ec_pubkey_combine(const secp256k1_context* ctx, secp256k1_pubkey *pubnonce, const secp256k1_pubkey * const *pubnonces, int n) {
int i;
secp256k1_gej Qj;
secp256k1_ge Q;
ARG_CHECK(pubnonce != NULL);
ARG_CHECK(n >= 1);
ARG_CHECK(pubnonces != NULL);
secp256k1_gej_set_infinity(&Qj);
for (i = 0; i < n; i++) {
secp256k1_pubkey_load(ctx, &Q, pubnonces[i]);
secp256k1_gej_add_ge(&Qj, &Qj, &Q);
}
if (secp256k1_gej_is_infinity(&Qj)) {
memset(pubnonce, 0, sizeof(*pubnonce));
return 0;
}
secp256k1_ge_set_gej(&Q, &Qj);
secp256k1_pubkey_save(pubnonce, &Q);
return 1;
}
#ifdef ENABLE_MODULE_ECDH
# include "modules/ecdh/main_impl.h"
#endif
#ifdef ENABLE_MODULE_SCHNORR
# include "modules/schnorr/main_impl.h"
#endif
#ifdef ENABLE_MODULE_RECOVERY
# include "modules/recovery/main_impl.h"
#endif

@ -18,7 +18,7 @@ static uint32_t secp256k1_test_rng_precomputed[8];
static int secp256k1_test_rng_precomputed_used = 8;
SECP256K1_INLINE static void secp256k1_rand_seed(const unsigned char *seed16) {
secp256k1_rfc6979_hmac_sha256_initialize(&secp256k1_test_rng, (const unsigned char*)"TestRNG", 7, seed16, 16, NULL, 0);
secp256k1_rfc6979_hmac_sha256_initialize(&secp256k1_test_rng, seed16, 16);
}
SECP256K1_INLINE static uint32_t secp256k1_rand32(void) {

@ -15,6 +15,15 @@
#include <stdint.h>
#include <stdio.h>
typedef struct {
void (*fn)(const char *text, void* data);
const void* data;
} secp256k1_callback;
static SECP256K1_INLINE void secp256k1_callback_call(const secp256k1_callback * const cb, const char * const text) {
cb->fn(text, (void*)cb->data);
}
#ifdef DETERMINISTIC
#define TEST_FAILURE(msg) do { \
fprintf(stderr, "%s\n", msg); \
@ -47,23 +56,20 @@
} while(0)
#endif
/* Like assert(), but safe to use on expressions with side effects. */
#ifndef NDEBUG
#define DEBUG_CHECK CHECK
#else
#define DEBUG_CHECK(cond) do { (void)(cond); } while(0)
#endif
/* Like DEBUG_CHECK(), but when VERIFY is defined instead of NDEBUG not defined. */
/* Like assert(), but when VERIFY is defined, and side-effect safe. */
#ifdef VERIFY
#define VERIFY_CHECK CHECK
#define VERIFY_SETUP(stmt) do { stmt; } while(0)
#else
#define VERIFY_CHECK(cond) do { (void)(cond); } while(0)
#define VERIFY_SETUP(stmt)
#endif
static SECP256K1_INLINE void *checked_malloc(size_t size) {
static SECP256K1_INLINE void *checked_malloc(const secp256k1_callback* cb, size_t size) {
void *ret = malloc(size);
CHECK(ret != NULL);
if (ret == NULL) {
secp256k1_callback_call(cb, "Out of memory");
}
return ret;
}

@ -19,7 +19,7 @@ package secp256k1
// TODO: set USE_SCALAR_4X64 depending on platform?
/*
#cgo CFLAGS: -I./secp256k1
#cgo CFLAGS: -I./libsecp256k1
#cgo darwin CFLAGS: -I/usr/local/include
#cgo freebsd CFLAGS: -I/usr/local/include
#cgo linux,arm CFLAGS: -I/usr/local/arm/include
@ -33,7 +33,8 @@ package secp256k1
#define USE_SCALAR_8X32
#define USE_SCALAR_INV_BUILTIN
#define NDEBUG
#include "./secp256k1/src/secp256k1.c"
#include "./libsecp256k1/src/secp256k1.c"
#include "./libsecp256k1/src/modules/recovery/main_impl.h"
*/
import "C"
@ -48,48 +49,51 @@ import (
//#define USE_FIELD_5X64
/*
Todo:
> Centralize key management in module
> add pubkey/private key struct
> Dont let keys leave module; address keys as ints
TODO:
> store private keys in buffer and shuffle (deters persistance on swap disc)
> Byte permutation (changing)
> byte permutation (changing)
> xor with chaning random block (to deter scanning memory for 0x63) (stream cipher?)
On Disk
> Store keys in wallets
> use slow key derivation function for wallet encryption key (2 seconds)
> on disk: store keys in wallets
*/
func init() {
//takes 10ms to 100ms
C.secp256k1_start(3) // SECP256K1_START_SIGN | SECP256K1_START_VERIFY
}
// holds ptr to secp256k1_context_struct (see secp256k1/include/secp256k1.h)
var context *C.secp256k1_context
func Stop() {
C.secp256k1_stop()
func init() {
// around 20 ms on a modern CPU.
context = C.secp256k1_context_create(3) // SECP256K1_START_SIGN | SECP256K1_START_VERIFY
}
func GenerateKeyPair() ([]byte, []byte) {
pubkey_len := C.int(65)
const seckey_len = 32
var pubkey []byte = make([]byte, pubkey_len)
var seckey []byte = randentropy.GetEntropyCSPRNG(seckey_len)
var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
var seckey []byte = randentropy.GetEntropyCSPRNG(32)
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
var pubkey64 []byte = make([]byte, 64) // secp256k1_pubkey
var pubkey65 []byte = make([]byte, 65) // 65 byte uncompressed pubkey
pubkey64_ptr := (*C.secp256k1_pubkey)(unsafe.Pointer(&pubkey64[0]))
pubkey65_ptr := (*C.uchar)(unsafe.Pointer(&pubkey65[0]))
ret := C.secp256k1_ec_pubkey_create(
pubkey_ptr, &pubkey_len,
seckey_ptr, 0)
context,
pubkey64_ptr,
seckey_ptr,
)
if ret != C.int(1) {
return GenerateKeyPair() //invalid secret, try again
return GenerateKeyPair() // invalid secret, try again
}
return pubkey, seckey
var output_len C.size_t
C.secp256k1_ec_pubkey_serialize( // always returns 1
context,
pubkey65_ptr,
&output_len,
pubkey64_ptr,
0, // SECP256K1_EC_COMPRESSED
)
return pubkey65, seckey
}
func GeneratePubKey(seckey []byte) ([]byte, error) {
@ -97,17 +101,16 @@ func GeneratePubKey(seckey []byte) ([]byte, error) {
return nil, err
}
pubkey_len := C.int(65)
const seckey_len = 32
var pubkey []byte = make([]byte, 64)
var pubkey_ptr *C.secp256k1_pubkey = (*C.secp256k1_pubkey)(unsafe.Pointer(&pubkey[0]))
var pubkey []byte = make([]byte, pubkey_len)
var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
ret := C.secp256k1_ec_pubkey_create(
pubkey_ptr, &pubkey_len,
seckey_ptr, 0)
context,
pubkey_ptr,
seckey_ptr,
)
if ret != C.int(1) {
return nil, errors.New("Unable to generate pubkey from seckey")
@ -117,38 +120,48 @@ func GeneratePubKey(seckey []byte) ([]byte, error) {
}
func Sign(msg []byte, seckey []byte) ([]byte, error) {
nonce := randentropy.GetEntropyCSPRNG(32)
msg_ptr := (*C.uchar)(unsafe.Pointer(&msg[0]))
seckey_ptr := (*C.uchar)(unsafe.Pointer(&seckey[0]))
var sig []byte = make([]byte, 65)
var recid C.int
sig := make([]byte, 65)
sig_ptr := (*C.secp256k1_ecdsa_recoverable_signature)(unsafe.Pointer(&sig[0]))
var msg_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&msg[0]))
var sig_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&sig[0]))
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
nonce := randentropy.GetEntropyCSPRNG(32)
ndata_ptr := unsafe.Pointer(&nonce[0])
var noncefp_ptr = &(*C.secp256k1_nonce_function_default)
var ndata_ptr = unsafe.Pointer(&nonce[0])
noncefp_ptr := &(*C.secp256k1_nonce_function_default)
if C.secp256k1_ec_seckey_verify(seckey_ptr) != C.int(1) {
if C.secp256k1_ec_seckey_verify(context, seckey_ptr) != C.int(1) {
return nil, errors.New("Invalid secret key")
}
ret := C.secp256k1_ecdsa_sign_compact(
msg_ptr,
ret := C.secp256k1_ecdsa_sign_recoverable(
context,
sig_ptr,
msg_ptr,
seckey_ptr,
noncefp_ptr,
ndata_ptr,
&recid)
sig[64] = byte(int(recid))
)
if ret != C.int(1) {
// nonce invalid, retry
return Sign(msg, seckey)
if ret == C.int(0) {
return Sign(msg, seckey) //invalid secret, try again
}
return sig, nil
sig_serialized := make([]byte, 65)
sig_serialized_ptr := (*C.uchar)(unsafe.Pointer(&sig_serialized[0]))
var recid C.int
C.secp256k1_ecdsa_recoverable_signature_serialize_compact(
context,
sig_serialized_ptr, // 64 byte compact signature
&recid,
sig_ptr, // 65 byte "recoverable" signature
)
sig_serialized[64] = byte(int(recid)) // add back recid to get 65 bytes sig
return sig_serialized, nil
}
@ -157,26 +170,13 @@ func VerifySeckeyValidity(seckey []byte) error {
return errors.New("priv key is not 32 bytes")
}
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
ret := C.secp256k1_ec_seckey_verify(seckey_ptr)
ret := C.secp256k1_ec_seckey_verify(context, seckey_ptr)
if int(ret) != 1 {
return errors.New("invalid seckey")
}
return nil
}
func VerifyPubkeyValidity(pubkey []byte) error {
if len(pubkey) != 65 {
return errors.New("pub key is not 65 bytes")
}
var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
ret := C.secp256k1_ec_pubkey_verify(pubkey_ptr, 65)
if int(ret) != 1 {
return errors.New("invalid pubkey")
}
return nil
}
func VerifySignatureValidity(sig []byte) bool {
//64+1
if len(sig) != 65 {
@ -231,36 +231,58 @@ func VerifySignature(msg []byte, sig []byte, pubkey1 []byte) error {
return nil
}
//recovers the public key from the signature
//recovery of pubkey means correct signature
// recovers a public key from the signature
func RecoverPubkey(msg []byte, sig []byte) ([]byte, error) {
if len(sig) != 65 {
return nil, errors.New("Invalid signature length")
}
var pubkey []byte = make([]byte, 65)
var msg_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&msg[0]))
var sig_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&sig[0]))
var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
msg_ptr := (*C.uchar)(unsafe.Pointer(&msg[0]))
sig_ptr := (*C.uchar)(unsafe.Pointer(&sig[0]))
pubkey := make([]byte, 64)
/*
this slice is used for both the recoverable signature and the
resulting serialized pubkey (both types in libsecp256k1 are 65
bytes). this saves one allocation of 65 bytes, which is nice as
pubkey recovery is one bottleneck during load in Ethereum
*/
bytes65 := make([]byte, 65)
pubkey_ptr := (*C.secp256k1_pubkey)(unsafe.Pointer(&pubkey[0]))
recoverable_sig_ptr := (*C.secp256k1_ecdsa_recoverable_signature)(unsafe.Pointer(&bytes65[0]))
recid := C.int(sig[64])
ret := C.secp256k1_ecdsa_recoverable_signature_parse_compact(
context,
recoverable_sig_ptr,
sig_ptr,
recid)
var pubkeylen C.int
if ret == C.int(0) {
return nil, errors.New("Failed to parse signature")
}
ret := C.secp256k1_ecdsa_recover_compact(
msg_ptr,
sig_ptr,
ret = C.secp256k1_ecdsa_recover(
context,
pubkey_ptr,
&pubkeylen,
C.int(0),
C.int(sig[64]),
recoverable_sig_ptr,
msg_ptr,
)
if ret == C.int(0) {
return nil, errors.New("Failed to recover public key")
} else if pubkeylen != C.int(65) {
return nil, errors.New("Impossible Error: Invalid recovered public key length")
} else {
return pubkey, nil
serialized_pubkey_ptr := (*C.uchar)(unsafe.Pointer(&bytes65[0]))
var output_len C.size_t
C.secp256k1_ec_pubkey_serialize( // always returns 1
context,
serialized_pubkey_ptr,
&output_len,
pubkey_ptr,
0, // SECP256K1_EC_COMPRESSED
)
return bytes65, nil
}
return nil, errors.New("Impossible Error: func RecoverPubkey has reached an unreachable state")
}

@ -18,169 +18,130 @@ package secp256k1
import (
"bytes"
"fmt"
"log"
"encoding/hex"
"testing"
"github.com/ethereum/go-ethereum/crypto/randentropy"
)
const TESTS = 10000 // how many tests
const SigSize = 65 //64+1
const TestCount = 10000
func Test_Secp256_00(t *testing.T) {
var nonce []byte = randentropy.GetEntropyCSPRNG(32) //going to get bitcoins stolen!
if len(nonce) != 32 {
t.Fatal()
}
}
//tests for Malleability
//highest bit of S must be 0; 32nd byte
func CompactSigTest(sig []byte) {
var b int = int(sig[32])
if b < 0 {
log.Panic()
}
if ((b >> 7) == 1) != ((b & 0x80) == 0x80) {
log.Panic("b= %v b2= %v \n", b, b>>7)
}
if (b & 0x80) == 0x80 {
log.Panic("b= %v b2= %v \n", b, b&0x80)
}
}
//test pubkey/private generation
func Test_Secp256_01(t *testing.T) {
pubkey, seckey := GenerateKeyPair()
func TestPrivkeyGenerate(t *testing.T) {
_, seckey := GenerateKeyPair()
if err := VerifySeckeyValidity(seckey); err != nil {
t.Fatal()
}
if err := VerifyPubkeyValidity(pubkey); err != nil {
t.Fatal()
t.Errorf("seckey not valid: %s", err)
}
}
//test size of messages
func Test_Secp256_02s(t *testing.T) {
func TestSignatureValidity(t *testing.T) {
pubkey, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
if sig == nil {
t.Fatal("Signature nil")
sig, err := Sign(msg, seckey)
if err != nil {
t.Errorf("signature error: %s", err)
}
compactSigCheck(t, sig)
if len(pubkey) != 65 {
t.Fail()
t.Errorf("pubkey length mismatch: want: 65 have: %d", len(pubkey))
}
if len(seckey) != 32 {
t.Fail()
t.Errorf("seckey length mismatch: want: 32 have: %d", len(seckey))
}
if len(sig) != 64+1 {
t.Fail()
if len(sig) != 65 {
t.Errorf("sig length mismatch: want: 65 have: %d", len(sig))
}
recid := int(sig[64])
if recid > 4 || recid < 0 {
t.Errorf("sig recid mismatch: want: within 0 to 4 have: %d", int(sig[64]))
}
if int(sig[64]) > 4 {
t.Fail()
} //should be 0 to 4
}
//test signing message
func Test_Secp256_02(t *testing.T) {
func TestSignAndRecover(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
if sig == nil {
t.Fatal("Signature nil")
sig, err := Sign(msg, seckey)
if err != nil {
t.Errorf("signature error: %s", err)
}
pubkey2, _ := RecoverPubkey(msg, sig)
if pubkey2 == nil {
t.Fatal("Recovered pubkey invalid")
pubkey2, err := RecoverPubkey(msg, sig)
if err != nil {
t.Errorf("recover error: %s", err)
}
if bytes.Equal(pubkey1, pubkey2) == false {
t.Fatal("Recovered pubkey does not match")
if !bytes.Equal(pubkey1, pubkey2) {
t.Errorf("pubkey mismatch: want: %x have: %x", pubkey1, pubkey2)
}
err := VerifySignature(msg, sig, pubkey1)
err = VerifySignature(msg, sig, pubkey1)
if err != nil {
t.Fatal("Signature invalid")
t.Errorf("signature verification error: %s", err)
}
}
//test pubkey recovery
func Test_Secp256_02a(t *testing.T) {
pubkey1, seckey1 := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey1)
if sig == nil {
t.Fatal("Signature nil")
}
err := VerifySignature(msg, sig, pubkey1)
if err != nil {
t.Fatal("Signature invalid")
func TestRandomMessagesWithSameKey(t *testing.T) {
pubkey, seckey := GenerateKeyPair()
keys := func() ([]byte, []byte) {
// Sign function zeroes the privkey so we need a new one in each call
newkey := make([]byte, len(seckey))
copy(newkey, seckey)
return pubkey, newkey
}
signAndRecoverWithRandomMessages(t, keys)
}
pubkey2, _ := RecoverPubkey(msg, sig)
if len(pubkey1) != len(pubkey2) {
t.Fatal()
}
for i, _ := range pubkey1 {
if pubkey1[i] != pubkey2[i] {
t.Fatal()
}
}
if bytes.Equal(pubkey1, pubkey2) == false {
t.Fatal()
func TestRandomMessagesWithRandomKeys(t *testing.T) {
keys := func() ([]byte, []byte) {
pubkey, seckey := GenerateKeyPair()
return pubkey, seckey
}
signAndRecoverWithRandomMessages(t, keys)
}
//test random messages for the same pub/private key
func Test_Secp256_03(t *testing.T) {
_, seckey := GenerateKeyPair()
for i := 0; i < TESTS; i++ {
func signAndRecoverWithRandomMessages(t *testing.T, keys func() ([]byte, []byte)) {
for i := 0; i < TestCount; i++ {
pubkey1, seckey := keys()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
sig, err := Sign(msg, seckey)
if err != nil {
t.Fatalf("signature error: %s", err)
}
if sig == nil {
t.Fatal("signature is nil")
}
compactSigCheck(t, sig)
// TODO: why do we flip around the recovery id?
sig[len(sig)-1] %= 4
pubkey2, _ := RecoverPubkey(msg, sig)
pubkey2, err := RecoverPubkey(msg, sig)
if err != nil {
t.Fatalf("recover error: %s", err)
}
if pubkey2 == nil {
t.Fail()
t.Error("pubkey is nil")
}
if !bytes.Equal(pubkey1, pubkey2) {
t.Fatalf("pubkey mismatch: want: %x have: %x", pubkey1, pubkey2)
}
}
}
//test random messages for different pub/private keys
func Test_Secp256_04(t *testing.T) {
for i := 0; i < TESTS; i++ {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
func TestRecoveryOfRandomSignature(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, err := Sign(msg, seckey)
if err != nil {
t.Errorf("signature error: %s", err)
}
if sig[len(sig)-1] >= 4 {
t.Fail()
}
for i := 0; i < TestCount; i++ {
sig = randSig()
pubkey2, _ := RecoverPubkey(msg, sig)
if pubkey2 == nil {
t.Fail()
}
if bytes.Equal(pubkey1, pubkey2) == false {
t.Fail()
// recovery can sometimes work, but if so should always give wrong pubkey
if bytes.Equal(pubkey1, pubkey2) {
t.Fatalf("iteration: %d: pubkey mismatch: do NOT want %x: ", i, pubkey2)
}
}
}
//test random signatures against fixed messages; should fail
//crashes:
// -SIPA look at this
func randSig() []byte {
sig := randentropy.GetEntropyCSPRNG(65)
sig[32] &= 0x70
@ -188,67 +149,83 @@ func randSig() []byte {
return sig
}
func Test_Secp256_06a_alt0(t *testing.T) {
func TestRandomMessagesAgainstValidSig(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
if sig == nil {
t.Fail()
}
if len(sig) != 65 {
t.Fail()
}
for i := 0; i < TESTS; i++ {
sig = randSig()
for i := 0; i < TestCount; i++ {
msg = randentropy.GetEntropyCSPRNG(32)
pubkey2, _ := RecoverPubkey(msg, sig)
if bytes.Equal(pubkey1, pubkey2) == true {
t.Fail()
}
if pubkey2 != nil && VerifySignature(msg, sig, pubkey2) != nil {
t.Fail()
}
if VerifySignature(msg, sig, pubkey1) == nil {
t.Fail()
// recovery can sometimes work, but if so should always give wrong pubkey
if bytes.Equal(pubkey1, pubkey2) {
t.Fatalf("iteration: %d: pubkey mismatch: do NOT want %x: ", i, pubkey2)
}
}
}
//test random messages against valid signature: should fail
func Test_Secp256_06b(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
func TestZeroPrivkey(t *testing.T) {
zeroedBytes := make([]byte, 32)
err := VerifySeckeyValidity(zeroedBytes)
if err == nil {
t.Errorf("zeroed bytes should have returned error")
}
}
fail_count := 0
for i := 0; i < TESTS; i++ {
msg = randentropy.GetEntropyCSPRNG(32)
pubkey2, _ := RecoverPubkey(msg, sig)
if bytes.Equal(pubkey1, pubkey2) == true {
t.Fail()
}
// Useful when the underlying libsecp256k1 API changes to quickly
// check only recover function without use of signature function
func TestRecoverSanity(t *testing.T) {
msg, _ := hex.DecodeString("ce0677bb30baa8cf067c88db9811f4333d131bf8bcf12fe7065d211dce971008")
sig, _ := hex.DecodeString("90f27b8b488db00b00606796d2987f6a5f59ae62ea05effe84fef5b8b0e549984a691139ad57a3f0b906637673aa2f63d1f55cb1a69199d4009eea23ceaddc9301")
pubkey1, _ := hex.DecodeString("04e32df42865e97135acfb65f3bae71bdc86f4d49150ad6a440b6f15878109880a0a2b2667f7e725ceea70c673093bf67663e0312623c8e091b13cf2c0f11ef652")
pubkey2, err := RecoverPubkey(msg, sig)
if err != nil {
t.Fatalf("recover error: %s", err)
}
if !bytes.Equal(pubkey1, pubkey2) {
t.Errorf("pubkey mismatch: want: %x have: %x", pubkey1, pubkey2)
}
}
if pubkey2 != nil && VerifySignature(msg, sig, pubkey2) != nil {
t.Fail()
}
// tests for malleability
// highest bit of signature ECDSA s value must be 0, in the 33th byte
func compactSigCheck(t *testing.T, sig []byte) {
var b int = int(sig[32])
if b < 0 {
t.Errorf("highest bit is negative: %d", b)
}
if ((b >> 7) == 1) != ((b & 0x80) == 0x80) {
t.Errorf("highest bit: %d bit >> 7: %d", b, b>>7)
}
if (b & 0x80) == 0x80 {
t.Errorf("highest bit: %d bit & 0x80: %d", b, b&0x80)
}
}
if VerifySignature(msg, sig, pubkey1) == nil {
t.Fail()
// godep go test -v -run=XXX -bench=BenchmarkSignRandomInputEachRound
// add -benchtime=10s to benchmark longer for more accurate average
func BenchmarkSignRandomInputEachRound(b *testing.B) {
for i := 0; i < b.N; i++ {
b.StopTimer()
_, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
b.StartTimer()
if _, err := Sign(msg, seckey); err != nil {
b.Fatal(err)
}
}
if fail_count != 0 {
fmt.Printf("ERROR: Accepted signature for %v of %v random messages\n", fail_count, TESTS)
}
}
func TestInvalidKey(t *testing.T) {
p1 := make([]byte, 32)
err := VerifySeckeyValidity(p1)
if err == nil {
t.Errorf("pvk %x varify sec key should have returned error", p1)
//godep go test -v -run=XXX -bench=BenchmarkRecoverRandomInputEachRound
func BenchmarkRecoverRandomInputEachRound(b *testing.B) {
for i := 0; i < b.N; i++ {
b.StopTimer()
_, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
b.StartTimer()
if _, err := RecoverPubkey(msg, sig); err != nil {
b.Fatal(err)
}
}
}

@ -1,32 +0,0 @@
language: c
compiler:
- clang
- gcc
install:
- sudo apt-get install -qq libssl-dev
- if [ "$BIGNUM" = "gmp" -o "$BIGNUM" = "auto" ]; then sudo apt-get install --no-install-recommends --no-upgrade -qq libgmp-dev; fi
- if [ -n "$EXTRAPACKAGES" ]; then sudo apt-get update && sudo apt-get install --no-install-recommends --no-upgrade $EXTRAPACKAGES; fi
env:
global:
- FIELD=auto BIGNUM=auto SCALAR=auto ENDOMORPHISM=no ASM=no BUILD=check EXTRAFLAGS= HOST= EXTRAPACKAGES=
matrix:
- SCALAR=32bit
- SCALAR=64bit
- FIELD=64bit
- FIELD=64bit ENDOMORPHISM=yes
- FIELD=64bit ASM=x86_64
- FIELD=64bit ENDOMORPHISM=yes ASM=x86_64
- FIELD=32bit
- FIELD=32bit ENDOMORPHISM=yes
- BIGNUM=no
- BIGNUM=no ENDOMORPHISM=yes
- BUILD=distcheck
- EXTRAFLAGS=CFLAGS=-DDETERMINISTIC
- HOST=i686-linux-gnu EXTRAPACKAGES="gcc-multilib"
- HOST=i686-linux-gnu EXTRAPACKAGES="gcc-multilib" ENDOMORPHISM=yes
before_script: ./autogen.sh
script:
- if [ -n "$HOST" ]; then export USE_HOST="--host=$HOST"; fi
- if [ "x$HOST" = "xi686-linux-gnu" ]; then export CC="$CC -m32"; fi
- ./configure --enable-endomorphism=$ENDOMORPHISM --with-field=$FIELD --with-bignum=$BIGNUM --with-scalar=$SCALAR $EXTRAFLAGS $USE_HOST && make -j2 $BUILD
os: linux

@ -1,61 +0,0 @@
dnl libsecp25k1 helper checks
AC_DEFUN([SECP_INT128_CHECK],[
has_int128=$ac_cv_type___int128
])
dnl
AC_DEFUN([SECP_64BIT_ASM_CHECK],[
AC_MSG_CHECKING(for x86_64 assembly availability)
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
#include <stdint.h>]],[[
uint64_t a = 11, tmp;
__asm__ __volatile__("movq $0x100000000,%1; mulq %%rsi" : "+a"(a) : "S"(tmp) : "cc", "%rdx");
]])],[has_64bit_asm=yes],[has_64bit_asm=no])
AC_MSG_RESULT([$has_64bit_asm])
])
dnl
AC_DEFUN([SECP_OPENSSL_CHECK],[
if test x"$use_pkgconfig" = x"yes"; then
: #NOP
m4_ifdef([PKG_CHECK_MODULES],[
PKG_CHECK_MODULES([CRYPTO], [libcrypto], [has_libcrypto=yes],[has_libcrypto=no])
if test x"$has_libcrypto" = x"yes"; then
TEMP_LIBS="$LIBS"
LIBS="$LIBS $CRYPTO_LIBS"
AC_CHECK_LIB(crypto, main,[AC_DEFINE(HAVE_LIBCRYPTO,1,[Define this symbol if libcrypto is installed])],[has_libcrypto=no])
LIBS="$TEMP_LIBS"
fi
])
else
AC_CHECK_HEADER(openssl/crypto.h,[AC_CHECK_LIB(crypto, main,[has_libcrypto=yes; CRYPTO_LIBS=-lcrypto; AC_DEFINE(HAVE_LIBCRYPTO,1,[Define this symbol if libcrypto is installed])]
)])
LIBS=
fi
if test x"$has_libcrypto" = x"yes" && test x"$has_openssl_ec" = x; then
AC_MSG_CHECKING(for EC functions in libcrypto)
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
#include <openssl/ec.h>
#include <openssl/ecdsa.h>
#include <openssl/obj_mac.h>]],[[
EC_KEY *eckey = EC_KEY_new_by_curve_name(NID_secp256k1);
ECDSA_sign(0, NULL, 0, NULL, NULL, eckey);
ECDSA_verify(0, NULL, 0, NULL, 0, eckey);
EC_KEY_free(eckey);
]])],[has_openssl_ec=yes],[has_openssl_ec=no])
AC_MSG_RESULT([$has_openssl_ec])
fi
])
dnl
AC_DEFUN([SECP_GMP_CHECK],[
if test x"$has_gmp" != x"yes"; then
CPPFLAGS_TEMP="$CPPFLAGS"
CPPFLAGS="$GMP_CPPFLAGS $CPPFLAGS"
LIBS_TEMP="$LIBS"
LIBS="$GMP_LIBS $LIBS"
AC_CHECK_HEADER(gmp.h,[AC_CHECK_LIB(gmp, __gmpz_init,[has_gmp=yes; GMP_LIBS="$GMP_LIBS -lgmp"; AC_DEFINE(HAVE_LIBGMP,1,[Define this symbol if libgmp is installed])])])
CPPFLAGS="$CPPFLAGS_TEMP"
LIBS="$LIBS_TEMP"
fi
])

@ -1,295 +0,0 @@
#ifndef _SECP256K1_
# define _SECP256K1_
# ifdef __cplusplus
extern "C" {
# endif
# if !defined(SECP256K1_GNUC_PREREQ)
# if defined(__GNUC__)&&defined(__GNUC_MINOR__)
# define SECP256K1_GNUC_PREREQ(_maj,_min) \
((__GNUC__<<16)+__GNUC_MINOR__>=((_maj)<<16)+(_min))
# else
# define SECP256K1_GNUC_PREREQ(_maj,_min) 0
# endif
# endif
# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
# if SECP256K1_GNUC_PREREQ(2,7)
# define SECP256K1_INLINE __inline__
# elif (defined(_MSC_VER))
# define SECP256K1_INLINE __inline
# else
# define SECP256K1_INLINE
# endif
# else
# define SECP256K1_INLINE inline
# endif
/**Warning attributes
* NONNULL is not used if SECP256K1_BUILD is set to avoid the compiler optimizing out
* some paranoid null checks. */
# if defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
# define SECP256K1_WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__))
# else
# define SECP256K1_WARN_UNUSED_RESULT
# endif
# if !defined(SECP256K1_BUILD) && defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
# define SECP256K1_ARG_NONNULL(_x) __attribute__ ((__nonnull__(_x)))
# else
# define SECP256K1_ARG_NONNULL(_x)
# endif
/** Flags to pass to secp256k1_start. */
# define SECP256K1_START_VERIFY (1 << 0)
# define SECP256K1_START_SIGN (1 << 1)
/** Initialize the library. This may take some time (10-100 ms).
* You need to call this before calling any other function.
* It cannot run in parallel with any other functions, but once
* secp256k1_start() returns, all other functions are thread-safe.
*/
void secp256k1_start(unsigned int flags);
/** Free all memory associated with this library. After this, no
* functions can be called anymore, except secp256k1_start()
*/
void secp256k1_stop(void);
/** Verify an ECDSA signature.
* Returns: 1: correct signature
* 0: incorrect signature
* -1: invalid public key
* -2: invalid signature
* In: msg32: the 32-byte message hash being verified (cannot be NULL)
* sig: the signature being verified (cannot be NULL)
* siglen: the length of the signature
* pubkey: the public key to verify with (cannot be NULL)
* pubkeylen: the length of pubkey
* Requires starting using SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_verify(
const unsigned char *msg32,
const unsigned char *sig,
int siglen,
const unsigned char *pubkey,
int pubkeylen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
/** A pointer to a function to deterministically generate a nonce.
* Returns: 1 if a nonce was successfully generated. 0 will cause signing to fail.
* In: msg32: the 32-byte message hash being verified (will not be NULL)
* key32: pointer to a 32-byte secret key (will not be NULL)
* attempt: how many iterations we have tried to find a nonce.
* This will almost always be 0, but different attempt values
* are required to result in a different nonce.
* data: Arbitrary data pointer that is passed through.
* Out: nonce32: pointer to a 32-byte array to be filled by the function.
* Except for test cases, this function should compute some cryptographic hash of
* the message, the key and the attempt.
*/
typedef int (*secp256k1_nonce_function_t)(
unsigned char *nonce32,
const unsigned char *msg32,
const unsigned char *key32,
unsigned int attempt,
const void *data
);
/** An implementation of RFC6979 (using HMAC-SHA256) as nonce generation function.
* If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
* extra entropy.
*/
extern const secp256k1_nonce_function_t secp256k1_nonce_function_rfc6979;
/** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
extern const secp256k1_nonce_function_t secp256k1_nonce_function_default;
/** Create an ECDSA signature.
* Returns: 1: signature created
* 0: the nonce generation function failed, the private key was invalid, or there is not
* enough space in the signature (as indicated by siglen).
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
* Out: sig: pointer to an array where the signature will be placed (cannot be NULL)
* In/Out: siglen: pointer to an int with the length of sig, which will be updated
* to contain the actual signature length (<=72). If 0 is returned, this will be
* set to zero.
* Requires starting using SECP256K1_START_SIGN.
*
* The sig always has an s value in the lower half of the range (From 0x1
* to 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
* inclusive), unlike many other implementations.
* With ECDSA a third-party can can forge a second distinct signature
* of the same message given a single initial signature without knowing
* the key by setting s to its additive inverse mod-order, 'flipping' the
* sign of the random point R which is not included in the signature.
* Since the forgery is of the same message this isn't universally
* problematic, but in systems where message malleability or uniqueness
* of signatures is important this can cause issues. This forgery can be
* blocked by all verifiers forcing signers to use a canonical form. The
* lower-S form reduces the size of signatures slightly on average when
* variable length encodings (such as DER) are used and is cheap to
* verify, making it a good choice. Security of always using lower-S is
* assured because anyone can trivially modify a signature after the
* fact to enforce this property. Adjusting it inside the signing
* function avoids the need to re-serialize or have curve specific
* constants outside of the library. By always using a canonical form
* even in applications where it isn't needed it becomes possible to
* impose a requirement later if a need is discovered.
* No other forms of ECDSA malleability are known and none seem likely,
* but there is no formal proof that ECDSA, even with this additional
* restriction, is free of other malleability. Commonly used serialization
* schemes will also accept various non-unique encodings, so care should
* be taken when this property is required for an application.
*/
int secp256k1_ecdsa_sign(
const unsigned char *msg32,
unsigned char *sig,
int *siglen,
const unsigned char *seckey,
secp256k1_nonce_function_t noncefp,
const void *ndata
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Create a compact ECDSA signature (64 byte + recovery id).
* Returns: 1: signature created
* 0: the nonce generation function failed, or the secret key was invalid.
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
* Out: sig: pointer to a 64-byte array where the signature will be placed (cannot be NULL)
* In case 0 is returned, the returned signature length will be zero.
* recid: pointer to an int, which will be updated to contain the recovery id (can be NULL)
* Requires starting using SECP256K1_START_SIGN.
*/
int secp256k1_ecdsa_sign_compact(
const unsigned char *msg32,
unsigned char *sig64,
const unsigned char *seckey,
secp256k1_nonce_function_t noncefp,
const void *ndata,
int *recid
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Recover an ECDSA public key from a compact signature.
* Returns: 1: public key successfully recovered (which guarantees a correct signature).
* 0: otherwise.
* In: msg32: the 32-byte message hash assumed to be signed (cannot be NULL)
* sig64: signature as 64 byte array (cannot be NULL)
* compressed: whether to recover a compressed or uncompressed pubkey
* recid: the recovery id (0-3, as returned by ecdsa_sign_compact)
* Out: pubkey: pointer to a 33 or 65 byte array to put the pubkey (cannot be NULL)
* pubkeylen: pointer to an int that will contain the pubkey length (cannot be NULL)
* Requires starting using SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_recover_compact(
const unsigned char *msg32,
const unsigned char *sig64,
unsigned char *pubkey,
int *pubkeylen,
int compressed,
int recid
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Verify an ECDSA secret key.
* Returns: 1: secret key is valid
* 0: secret key is invalid
* In: seckey: pointer to a 32-byte secret key (cannot be NULL)
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(const unsigned char *seckey) SECP256K1_ARG_NONNULL(1);
/** Just validate a public key.
* Returns: 1: valid public key
* 0: invalid public key
* In: pubkey: pointer to a 33-byte or 65-byte public key (cannot be NULL).
* pubkeylen: length of pubkey
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_verify(const unsigned char *pubkey, int pubkeylen) SECP256K1_ARG_NONNULL(1);
/** Compute the public key for a secret key.
* In: compressed: whether the computed public key should be compressed
* seckey: pointer to a 32-byte private key (cannot be NULL)
* Out: pubkey: pointer to a 33-byte (if compressed) or 65-byte (if uncompressed)
* area to store the public key (cannot be NULL)
* pubkeylen: pointer to int that will be updated to contains the pubkey's
* length (cannot be NULL)
* Returns: 1: secret was valid, public key stores
* 0: secret was invalid, try again.
* Requires starting using SECP256K1_START_SIGN.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
unsigned char *pubkey,
int *pubkeylen,
const unsigned char *seckey,
int compressed
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Decompress a public key.
* In/Out: pubkey: pointer to a 65-byte array to put the decompressed public key.
It must contain a 33-byte or 65-byte public key already (cannot be NULL)
* pubkeylen: pointer to the size of the public key pointed to by pubkey (cannot be NULL)
It will be updated to reflect the new size.
* Returns: 0 if the passed public key was invalid, 1 otherwise. If 1 is returned, the
pubkey is replaced with its decompressed version.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_decompress(
unsigned char *pubkey,
int *pubkeylen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Export a private key in DER format. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_export(
const unsigned char *seckey,
unsigned char *privkey,
int *privkeylen,
int compressed
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Import a private key in DER format. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_import(
unsigned char *seckey,
const unsigned char *privkey,
int privkeylen
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Tweak a private key by adding tweak to it. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
unsigned char *seckey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Tweak a public key by adding tweak times the generator to it.
* Requires starting with SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
unsigned char *pubkey,
int pubkeylen,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
/** Tweak a private key by multiplying it with tweak. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
unsigned char *seckey,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Tweak a public key by multiplying it with tweak.
* Requires starting with SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
unsigned char *pubkey,
int pubkeylen,
const unsigned char *tweak
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
# ifdef __cplusplus
}
# endif
#endif

@ -1,23 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECDSA_
#define _SECP256K1_ECDSA_
#include "scalar.h"
#include "group.h"
typedef struct {
secp256k1_scalar_t r, s;
} secp256k1_ecdsa_sig_t;
static int secp256k1_ecdsa_sig_parse(secp256k1_ecdsa_sig_t *r, const unsigned char *sig, int size);
static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, int *size, const secp256k1_ecdsa_sig_t *a);
static int secp256k1_ecdsa_sig_verify(const secp256k1_ecdsa_sig_t *sig, const secp256k1_ge_t *pubkey, const secp256k1_scalar_t *message);
static int secp256k1_ecdsa_sig_sign(secp256k1_ecdsa_sig_t *sig, const secp256k1_scalar_t *seckey, const secp256k1_scalar_t *message, const secp256k1_scalar_t *nonce, int *recid);
static int secp256k1_ecdsa_sig_recover(const secp256k1_ecdsa_sig_t *sig, secp256k1_ge_t *pubkey, const secp256k1_scalar_t *message, int recid);
#endif

@ -1,24 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECKEY_
#define _SECP256K1_ECKEY_
#include "group.h"
#include "scalar.h"
static int secp256k1_eckey_pubkey_parse(secp256k1_ge_t *elem, const unsigned char *pub, int size);
static int secp256k1_eckey_pubkey_serialize(secp256k1_ge_t *elem, unsigned char *pub, int *size, int compressed);
static int secp256k1_eckey_privkey_parse(secp256k1_scalar_t *key, const unsigned char *privkey, int privkeylen);
static int secp256k1_eckey_privkey_serialize(unsigned char *privkey, int *privkeylen, const secp256k1_scalar_t *key, int compressed);
static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar_t *key, const secp256k1_scalar_t *tweak);
static int secp256k1_eckey_pubkey_tweak_add(secp256k1_ge_t *key, const secp256k1_scalar_t *tweak);
static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar_t *key, const secp256k1_scalar_t *tweak);
static int secp256k1_eckey_pubkey_tweak_mul(secp256k1_ge_t *key, const secp256k1_scalar_t *tweak);
#endif

@ -1,19 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_
#define _SECP256K1_ECMULT_
#include "num.h"
#include "group.h"
static void secp256k1_ecmult_start(void);
static void secp256k1_ecmult_stop(void);
/** Double multiply: R = na*A + ng*G */
static void secp256k1_ecmult(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_scalar_t *na, const secp256k1_scalar_t *ng);
#endif

@ -1,128 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_GEN_IMPL_H_
#define _SECP256K1_ECMULT_GEN_IMPL_H_
#include "scalar.h"
#include "group.h"
#include "ecmult_gen.h"
typedef struct {
/* For accelerating the computation of a*G:
* To harden against timing attacks, use the following mechanism:
* * Break up the multiplicand into groups of 4 bits, called n_0, n_1, n_2, ..., n_63.
* * Compute sum(n_i * 16^i * G + U_i, i=0..63), where:
* * U_i = U * 2^i (for i=0..62)
* * U_i = U * (1-2^63) (for i=63)
* where U is a point with no known corresponding scalar. Note that sum(U_i, i=0..63) = 0.
* For each i, and each of the 16 possible values of n_i, (n_i * 16^i * G + U_i) is
* precomputed (call it prec(i, n_i)). The formula now becomes sum(prec(i, n_i), i=0..63).
* None of the resulting prec group elements have a known scalar, and neither do any of
* the intermediate sums while computing a*G.
*/
secp256k1_ge_storage_t prec[64][16]; /* prec[j][i] = 16^j * i * G + U_i */
} secp256k1_ecmult_gen_consts_t;
static const secp256k1_ecmult_gen_consts_t *secp256k1_ecmult_gen_consts = NULL;
static void secp256k1_ecmult_gen_start(void) {
secp256k1_ge_t prec[1024];
secp256k1_gej_t gj;
secp256k1_gej_t nums_gej;
secp256k1_ecmult_gen_consts_t *ret;
int i, j;
if (secp256k1_ecmult_gen_consts != NULL) {
return;
}
/* Allocate the precomputation table. */
ret = (secp256k1_ecmult_gen_consts_t*)checked_malloc(sizeof(secp256k1_ecmult_gen_consts_t));
/* get the generator */
secp256k1_gej_set_ge(&gj, &secp256k1_ge_const_g);
/* Construct a group element with no known corresponding scalar (nothing up my sleeve). */
{
static const unsigned char nums_b32[33] = "The scalar for this x is unknown";
secp256k1_fe_t nums_x;
secp256k1_ge_t nums_ge;
VERIFY_CHECK(secp256k1_fe_set_b32(&nums_x, nums_b32));
VERIFY_CHECK(secp256k1_ge_set_xo_var(&nums_ge, &nums_x, 0));
secp256k1_gej_set_ge(&nums_gej, &nums_ge);
/* Add G to make the bits in x uniformly distributed. */
secp256k1_gej_add_ge_var(&nums_gej, &nums_gej, &secp256k1_ge_const_g);
}
/* compute prec. */
{
secp256k1_gej_t precj[1024]; /* Jacobian versions of prec. */
secp256k1_gej_t gbase;
secp256k1_gej_t numsbase;
gbase = gj; /* 16^j * G */
numsbase = nums_gej; /* 2^j * nums. */
for (j = 0; j < 64; j++) {
/* Set precj[j*16 .. j*16+15] to (numsbase, numsbase + gbase, ..., numsbase + 15*gbase). */
precj[j*16] = numsbase;
for (i = 1; i < 16; i++) {
secp256k1_gej_add_var(&precj[j*16 + i], &precj[j*16 + i - 1], &gbase);
}
/* Multiply gbase by 16. */
for (i = 0; i < 4; i++) {
secp256k1_gej_double_var(&gbase, &gbase);
}
/* Multiply numbase by 2. */
secp256k1_gej_double_var(&numsbase, &numsbase);
if (j == 62) {
/* In the last iteration, numsbase is (1 - 2^j) * nums instead. */
secp256k1_gej_neg(&numsbase, &numsbase);
secp256k1_gej_add_var(&numsbase, &numsbase, &nums_gej);
}
}
secp256k1_ge_set_all_gej_var(1024, prec, precj);
}
for (j = 0; j < 64; j++) {
for (i = 0; i < 16; i++) {
secp256k1_ge_to_storage(&ret->prec[j][i], &prec[j*16 + i]);
}
}
/* Set the global pointer to the precomputation table. */
secp256k1_ecmult_gen_consts = ret;
}
static void secp256k1_ecmult_gen_stop(void) {
secp256k1_ecmult_gen_consts_t *c;
if (secp256k1_ecmult_gen_consts == NULL) {
return;
}
c = (secp256k1_ecmult_gen_consts_t*)secp256k1_ecmult_gen_consts;
secp256k1_ecmult_gen_consts = NULL;
free(c);
}
static void secp256k1_ecmult_gen(secp256k1_gej_t *r, const secp256k1_scalar_t *gn) {
const secp256k1_ecmult_gen_consts_t *c = secp256k1_ecmult_gen_consts;
secp256k1_ge_t add;
secp256k1_ge_storage_t adds;
int bits;
int i, j;
secp256k1_gej_set_infinity(r);
add.infinity = 0;
for (j = 0; j < 64; j++) {
bits = secp256k1_scalar_get_bits(gn, j * 4, 4);
for (i = 0; i < 16; i++) {
secp256k1_ge_storage_cmov(&adds, &c->prec[j][i], i == bits);
}
secp256k1_ge_from_storage(&add, &adds);
secp256k1_gej_add_ge(r, r, &add);
}
bits = 0;
secp256k1_ge_clear(&add);
}
#endif

@ -1,302 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_ECMULT_IMPL_H_
#define _SECP256K1_ECMULT_IMPL_H_
#include "group.h"
#include "scalar.h"
#include "ecmult.h"
/* optimal for 128-bit and 256-bit exponents. */
#define WINDOW_A 5
/** larger numbers may result in slightly better performance, at the cost of
exponentially larger precomputed tables. */
#ifdef USE_ENDOMORPHISM
/** Two tables for window size 15: 1.375 MiB. */
#define WINDOW_G 15
#else
/** One table for window size 16: 1.375 MiB. */
#define WINDOW_G 16
#endif
/** Fill a table 'pre' with precomputed odd multiples of a. W determines the size of the table.
* pre will contains the values [1*a,3*a,5*a,...,(2^(w-1)-1)*a], so it needs place for
* 2^(w-2) entries.
*
* There are two versions of this function:
* - secp256k1_ecmult_precomp_wnaf_gej, which operates on group elements in jacobian notation,
* fast to precompute, but slower to use in later additions.
* - secp256k1_ecmult_precomp_wnaf_ge, which operates on group elements in affine notations,
* (much) slower to precompute, but a bit faster to use in later additions.
* To compute a*P + b*G, we use the jacobian version for P, and the affine version for G, as
* G is constant, so it only needs to be done once in advance.
*/
static void secp256k1_ecmult_table_precomp_gej_var(secp256k1_gej_t *pre, const secp256k1_gej_t *a, int w) {
secp256k1_gej_t d;
int i;
pre[0] = *a;
secp256k1_gej_double_var(&d, &pre[0]);
for (i = 1; i < (1 << (w-2)); i++) {
secp256k1_gej_add_var(&pre[i], &d, &pre[i-1]);
}
}
static void secp256k1_ecmult_table_precomp_ge_storage_var(secp256k1_ge_storage_t *pre, const secp256k1_gej_t *a, int w) {
secp256k1_gej_t d;
int i;
const int table_size = 1 << (w-2);
secp256k1_gej_t *prej = (secp256k1_gej_t *)checked_malloc(sizeof(secp256k1_gej_t) * table_size);
secp256k1_ge_t *prea = (secp256k1_ge_t *)checked_malloc(sizeof(secp256k1_ge_t) * table_size);
prej[0] = *a;
secp256k1_gej_double_var(&d, a);
for (i = 1; i < table_size; i++) {
secp256k1_gej_add_var(&prej[i], &d, &prej[i-1]);
}
secp256k1_ge_set_all_gej_var(table_size, prea, prej);
for (i = 0; i < table_size; i++) {
secp256k1_ge_to_storage(&pre[i], &prea[i]);
}
free(prej);
free(prea);
}
/** The number of entries a table with precomputed multiples needs to have. */
#define ECMULT_TABLE_SIZE(w) (1 << ((w)-2))
/** The following two macro retrieves a particular odd multiple from a table
* of precomputed multiples. */
#define ECMULT_TABLE_GET_GEJ(r,pre,n,w) do { \
VERIFY_CHECK(((n) & 1) == 1); \
VERIFY_CHECK((n) >= -((1 << ((w)-1)) - 1)); \
VERIFY_CHECK((n) <= ((1 << ((w)-1)) - 1)); \
if ((n) > 0) { \
*(r) = (pre)[((n)-1)/2]; \
} else { \
secp256k1_gej_neg((r), &(pre)[(-(n)-1)/2]); \
} \
} while(0)
#define ECMULT_TABLE_GET_GE_STORAGE(r,pre,n,w) do { \
VERIFY_CHECK(((n) & 1) == 1); \
VERIFY_CHECK((n) >= -((1 << ((w)-1)) - 1)); \
VERIFY_CHECK((n) <= ((1 << ((w)-1)) - 1)); \
if ((n) > 0) { \
secp256k1_ge_from_storage((r), &(pre)[((n)-1)/2]); \
} else { \
secp256k1_ge_from_storage((r), &(pre)[(-(n)-1)/2]); \
secp256k1_ge_neg((r), (r)); \
} \
} while(0)
typedef struct {
/* For accelerating the computation of a*P + b*G: */
secp256k1_ge_storage_t pre_g[ECMULT_TABLE_SIZE(WINDOW_G)]; /* odd multiples of the generator */
#ifdef USE_ENDOMORPHISM
secp256k1_ge_storage_t pre_g_128[ECMULT_TABLE_SIZE(WINDOW_G)]; /* odd multiples of 2^128*generator */
#endif
} secp256k1_ecmult_consts_t;
static const secp256k1_ecmult_consts_t *secp256k1_ecmult_consts = NULL;
static void secp256k1_ecmult_start(void) {
secp256k1_gej_t gj;
secp256k1_ecmult_consts_t *ret;
if (secp256k1_ecmult_consts != NULL) {
return;
}
/* Allocate the precomputation table. */
ret = (secp256k1_ecmult_consts_t*)checked_malloc(sizeof(secp256k1_ecmult_consts_t));
/* get the generator */
secp256k1_gej_set_ge(&gj, &secp256k1_ge_const_g);
/* precompute the tables with odd multiples */
secp256k1_ecmult_table_precomp_ge_storage_var(ret->pre_g, &gj, WINDOW_G);
#ifdef USE_ENDOMORPHISM
{
secp256k1_gej_t g_128j;
int i;
/* calculate 2^128*generator */
g_128j = gj;
for (i = 0; i < 128; i++) {
secp256k1_gej_double_var(&g_128j, &g_128j);
}
secp256k1_ecmult_table_precomp_ge_storage_var(ret->pre_g_128, &g_128j, WINDOW_G);
}
#endif
/* Set the global pointer to the precomputation table. */
secp256k1_ecmult_consts = ret;
}
static void secp256k1_ecmult_stop(void) {
secp256k1_ecmult_consts_t *c;
if (secp256k1_ecmult_consts == NULL) {
return;
}
c = (secp256k1_ecmult_consts_t*)secp256k1_ecmult_consts;
secp256k1_ecmult_consts = NULL;
free(c);
}
/** Convert a number to WNAF notation. The number becomes represented by sum(2^i * wnaf[i], i=0..bits),
* with the following guarantees:
* - each wnaf[i] is either 0, or an odd integer between -(1<<(w-1) - 1) and (1<<(w-1) - 1)
* - two non-zero entries in wnaf are separated by at least w-1 zeroes.
* - the number of set values in wnaf is returned. This number is at most 256, and at most one more
* - than the number of bits in the (absolute value) of the input.
*/
static int secp256k1_ecmult_wnaf(int *wnaf, const secp256k1_scalar_t *a, int w) {
secp256k1_scalar_t s = *a;
int set_bits = 0;
int bit = 0;
int sign = 1;
if (secp256k1_scalar_get_bits(&s, 255, 1)) {
secp256k1_scalar_negate(&s, &s);
sign = -1;
}
while (bit < 256) {
int now;
int word;
if (secp256k1_scalar_get_bits(&s, bit, 1) == 0) {
bit++;
continue;
}
while (set_bits < bit) {
wnaf[set_bits++] = 0;
}
now = w;
if (bit + now > 256) {
now = 256 - bit;
}
word = secp256k1_scalar_get_bits_var(&s, bit, now);
if (word & (1 << (w-1))) {
secp256k1_scalar_add_bit(&s, bit + w);
wnaf[set_bits++] = sign * (word - (1 << w));
} else {
wnaf[set_bits++] = sign * word;
}
bit += now;
}
return set_bits;
}
static void secp256k1_ecmult(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_scalar_t *na, const secp256k1_scalar_t *ng) {
secp256k1_gej_t tmpj;
secp256k1_gej_t pre_a[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_ge_t tmpa;
const secp256k1_ecmult_consts_t *c = secp256k1_ecmult_consts;
#ifdef USE_ENDOMORPHISM
secp256k1_gej_t pre_a_lam[ECMULT_TABLE_SIZE(WINDOW_A)];
secp256k1_scalar_t na_1, na_lam;
/* Splitted G factors. */
secp256k1_scalar_t ng_1, ng_128;
int wnaf_na_1[130];
int wnaf_na_lam[130];
int bits_na_1;
int bits_na_lam;
int wnaf_ng_1[129];
int bits_ng_1;
int wnaf_ng_128[129];
int bits_ng_128;
#else
int wnaf_na[256];
int bits_na;
int wnaf_ng[257];
int bits_ng;
#endif
int i;
int bits;
#ifdef USE_ENDOMORPHISM
/* split na into na_1 and na_lam (where na = na_1 + na_lam*lambda, and na_1 and na_lam are ~128 bit) */
secp256k1_scalar_split_lambda_var(&na_1, &na_lam, na);
/* build wnaf representation for na_1 and na_lam. */
bits_na_1 = secp256k1_ecmult_wnaf(wnaf_na_1, &na_1, WINDOW_A);
bits_na_lam = secp256k1_ecmult_wnaf(wnaf_na_lam, &na_lam, WINDOW_A);
VERIFY_CHECK(bits_na_1 <= 130);
VERIFY_CHECK(bits_na_lam <= 130);
bits = bits_na_1;
if (bits_na_lam > bits) {
bits = bits_na_lam;
}
#else
/* build wnaf representation for na. */
bits_na = secp256k1_ecmult_wnaf(wnaf_na, na, WINDOW_A);
bits = bits_na;
#endif
/* calculate odd multiples of a */
secp256k1_ecmult_table_precomp_gej_var(pre_a, a, WINDOW_A);
#ifdef USE_ENDOMORPHISM
for (i = 0; i < ECMULT_TABLE_SIZE(WINDOW_A); i++) {
secp256k1_gej_mul_lambda(&pre_a_lam[i], &pre_a[i]);
}
/* split ng into ng_1 and ng_128 (where gn = gn_1 + gn_128*2^128, and gn_1 and gn_128 are ~128 bit) */
secp256k1_scalar_split_128(&ng_1, &ng_128, ng);
/* Build wnaf representation for ng_1 and ng_128 */
bits_ng_1 = secp256k1_ecmult_wnaf(wnaf_ng_1, &ng_1, WINDOW_G);
bits_ng_128 = secp256k1_ecmult_wnaf(wnaf_ng_128, &ng_128, WINDOW_G);
if (bits_ng_1 > bits) {
bits = bits_ng_1;
}
if (bits_ng_128 > bits) {
bits = bits_ng_128;
}
#else
bits_ng = secp256k1_ecmult_wnaf(wnaf_ng, ng, WINDOW_G);
if (bits_ng > bits) {
bits = bits_ng;
}
#endif
secp256k1_gej_set_infinity(r);
for (i = bits-1; i >= 0; i--) {
int n;
secp256k1_gej_double_var(r, r);
#ifdef USE_ENDOMORPHISM
if (i < bits_na_1 && (n = wnaf_na_1[i])) {
ECMULT_TABLE_GET_GEJ(&tmpj, pre_a, n, WINDOW_A);
secp256k1_gej_add_var(r, r, &tmpj);
}
if (i < bits_na_lam && (n = wnaf_na_lam[i])) {
ECMULT_TABLE_GET_GEJ(&tmpj, pre_a_lam, n, WINDOW_A);
secp256k1_gej_add_var(r, r, &tmpj);
}
if (i < bits_ng_1 && (n = wnaf_ng_1[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, c->pre_g, n, WINDOW_G);
secp256k1_gej_add_ge_var(r, r, &tmpa);
}
if (i < bits_ng_128 && (n = wnaf_ng_128[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, c->pre_g_128, n, WINDOW_G);
secp256k1_gej_add_ge_var(r, r, &tmpa);
}
#else
if (i < bits_na && (n = wnaf_na[i])) {
ECMULT_TABLE_GET_GEJ(&tmpj, pre_a, n, WINDOW_A);
secp256k1_gej_add_var(r, r, &tmpj);
}
if (i < bits_ng && (n = wnaf_ng[i])) {
ECMULT_TABLE_GET_GE_STORAGE(&tmpa, c->pre_g, n, WINDOW_G);
secp256k1_gej_add_ge_var(r, r, &tmpa);
}
#endif
}
}
#endif

@ -1,118 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_GROUP_
#define _SECP256K1_GROUP_
#include "num.h"
#include "field.h"
/** A group element of the secp256k1 curve, in affine coordinates. */
typedef struct {
secp256k1_fe_t x;
secp256k1_fe_t y;
int infinity; /* whether this represents the point at infinity */
} secp256k1_ge_t;
#define SECP256K1_GE_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_CONST((i),(j),(k),(l),(m),(n),(o),(p)), 0}
#define SECP256K1_GE_CONST_INFINITY {SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), 1}
/** A group element of the secp256k1 curve, in jacobian coordinates. */
typedef struct {
secp256k1_fe_t x; /* actual X: x/z^2 */
secp256k1_fe_t y; /* actual Y: y/z^3 */
secp256k1_fe_t z;
int infinity; /* whether this represents the point at infinity */
} secp256k1_gej_t;
#define SECP256K1_GEJ_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_CONST((i),(j),(k),(l),(m),(n),(o),(p)), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 1), 0}
#define SECP256K1_GEJ_CONST_INFINITY {SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), SECP256K1_FE_CONST(0, 0, 0, 0, 0, 0, 0, 0), 1}
typedef struct {
secp256k1_fe_storage_t x;
secp256k1_fe_storage_t y;
} secp256k1_ge_storage_t;
#define SECP256K1_GE_STORAGE_CONST(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p) {SECP256K1_FE_STORAGE_CONST((a),(b),(c),(d),(e),(f),(g),(h)), SECP256K1_FE_STORAGE_CONST((i),(j),(k),(l),(m),(n),(o),(p))}
/** Set a group element equal to the point at infinity */
static void secp256k1_ge_set_infinity(secp256k1_ge_t *r);
/** Set a group element equal to the point with given X and Y coordinates */
static void secp256k1_ge_set_xy(secp256k1_ge_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y);
/** Set a group element (affine) equal to the point with the given X coordinate, and given oddness
* for Y. Return value indicates whether the result is valid. */
static int secp256k1_ge_set_xo_var(secp256k1_ge_t *r, const secp256k1_fe_t *x, int odd);
/** Check whether a group element is the point at infinity. */
static int secp256k1_ge_is_infinity(const secp256k1_ge_t *a);
/** Check whether a group element is valid (i.e., on the curve). */
static int secp256k1_ge_is_valid_var(const secp256k1_ge_t *a);
static void secp256k1_ge_neg(secp256k1_ge_t *r, const secp256k1_ge_t *a);
/** Set a group element equal to another which is given in jacobian coordinates */
static void secp256k1_ge_set_gej(secp256k1_ge_t *r, secp256k1_gej_t *a);
/** Set a batch of group elements equal to the inputs given in jacobian coordinates */
static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge_t *r, const secp256k1_gej_t *a);
/** Set a group element (jacobian) equal to the point at infinity. */
static void secp256k1_gej_set_infinity(secp256k1_gej_t *r);
/** Set a group element (jacobian) equal to the point with given X and Y coordinates. */
static void secp256k1_gej_set_xy(secp256k1_gej_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y);
/** Set a group element (jacobian) equal to another which is given in affine coordinates. */
static void secp256k1_gej_set_ge(secp256k1_gej_t *r, const secp256k1_ge_t *a);
/** Compare the X coordinate of a group element (jacobian). */
static int secp256k1_gej_eq_x_var(const secp256k1_fe_t *x, const secp256k1_gej_t *a);
/** Set r equal to the inverse of a (i.e., mirrored around the X axis) */
static void secp256k1_gej_neg(secp256k1_gej_t *r, const secp256k1_gej_t *a);
/** Check whether a group element is the point at infinity. */
static int secp256k1_gej_is_infinity(const secp256k1_gej_t *a);
/** Set r equal to the double of a. */
static void secp256k1_gej_double_var(secp256k1_gej_t *r, const secp256k1_gej_t *a);
/** Set r equal to the sum of a and b. */
static void secp256k1_gej_add_var(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_gej_t *b);
/** Set r equal to the sum of a and b (with b given in affine coordinates, and not infinity). */
static void secp256k1_gej_add_ge(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_ge_t *b);
/** Set r equal to the sum of a and b (with b given in affine coordinates). This is more efficient
than secp256k1_gej_add_var. It is identical to secp256k1_gej_add_ge but without constant-time
guarantee, and b is allowed to be infinity. */
static void secp256k1_gej_add_ge_var(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_ge_t *b);
#ifdef USE_ENDOMORPHISM
/** Set r to be equal to lambda times a, where lambda is chosen in a way such that this is very fast. */
static void secp256k1_gej_mul_lambda(secp256k1_gej_t *r, const secp256k1_gej_t *a);
#endif
/** Clear a secp256k1_gej_t to prevent leaking sensitive information. */
static void secp256k1_gej_clear(secp256k1_gej_t *r);
/** Clear a secp256k1_ge_t to prevent leaking sensitive information. */
static void secp256k1_ge_clear(secp256k1_ge_t *r);
/** Convert a group element to the storage type. */
static void secp256k1_ge_to_storage(secp256k1_ge_storage_t *r, const secp256k1_ge_t*);
/** Convert a group element back from the storage type. */
static void secp256k1_ge_from_storage(secp256k1_ge_t *r, const secp256k1_ge_storage_t*);
/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */
static void secp256k1_ge_storage_cmov(secp256k1_ge_storage_t *r, const secp256k1_ge_storage_t *a, int flag);
#endif

@ -1,434 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_GROUP_IMPL_H_
#define _SECP256K1_GROUP_IMPL_H_
#include <string.h>
#include "num.h"
#include "field.h"
#include "group.h"
/** Generator for secp256k1, value 'g' defined in
* "Standards for Efficient Cryptography" (SEC2) 2.7.1.
*/
static const secp256k1_ge_t secp256k1_ge_const_g = SECP256K1_GE_CONST(
0x79BE667EUL, 0xF9DCBBACUL, 0x55A06295UL, 0xCE870B07UL,
0x029BFCDBUL, 0x2DCE28D9UL, 0x59F2815BUL, 0x16F81798UL,
0x483ADA77UL, 0x26A3C465UL, 0x5DA4FBFCUL, 0x0E1108A8UL,
0xFD17B448UL, 0xA6855419UL, 0x9C47D08FUL, 0xFB10D4B8UL
);
static void secp256k1_ge_set_infinity(secp256k1_ge_t *r) {
r->infinity = 1;
}
static void secp256k1_ge_set_xy(secp256k1_ge_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y) {
r->infinity = 0;
r->x = *x;
r->y = *y;
}
static int secp256k1_ge_is_infinity(const secp256k1_ge_t *a) {
return a->infinity;
}
static void secp256k1_ge_neg(secp256k1_ge_t *r, const secp256k1_ge_t *a) {
*r = *a;
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
static void secp256k1_ge_set_gej(secp256k1_ge_t *r, secp256k1_gej_t *a) {
secp256k1_fe_t z2, z3;
r->infinity = a->infinity;
secp256k1_fe_inv(&a->z, &a->z);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_mul(&z3, &a->z, &z2);
secp256k1_fe_mul(&a->x, &a->x, &z2);
secp256k1_fe_mul(&a->y, &a->y, &z3);
secp256k1_fe_set_int(&a->z, 1);
r->x = a->x;
r->y = a->y;
}
static void secp256k1_ge_set_gej_var(secp256k1_ge_t *r, secp256k1_gej_t *a) {
secp256k1_fe_t z2, z3;
r->infinity = a->infinity;
if (a->infinity) {
return;
}
secp256k1_fe_inv_var(&a->z, &a->z);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_mul(&z3, &a->z, &z2);
secp256k1_fe_mul(&a->x, &a->x, &z2);
secp256k1_fe_mul(&a->y, &a->y, &z3);
secp256k1_fe_set_int(&a->z, 1);
r->x = a->x;
r->y = a->y;
}
static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge_t *r, const secp256k1_gej_t *a) {
secp256k1_fe_t *az;
secp256k1_fe_t *azi;
size_t i;
size_t count = 0;
az = (secp256k1_fe_t *)checked_malloc(sizeof(secp256k1_fe_t) * len);
for (i = 0; i < len; i++) {
if (!a[i].infinity) {
az[count++] = a[i].z;
}
}
azi = (secp256k1_fe_t *)checked_malloc(sizeof(secp256k1_fe_t) * count);
secp256k1_fe_inv_all_var(count, azi, az);
free(az);
count = 0;
for (i = 0; i < len; i++) {
r[i].infinity = a[i].infinity;
if (!a[i].infinity) {
secp256k1_fe_t zi2, zi3;
secp256k1_fe_t *zi = &azi[count++];
secp256k1_fe_sqr(&zi2, zi);
secp256k1_fe_mul(&zi3, &zi2, zi);
secp256k1_fe_mul(&r[i].x, &a[i].x, &zi2);
secp256k1_fe_mul(&r[i].y, &a[i].y, &zi3);
}
}
free(azi);
}
static void secp256k1_gej_set_infinity(secp256k1_gej_t *r) {
r->infinity = 1;
secp256k1_fe_set_int(&r->x, 0);
secp256k1_fe_set_int(&r->y, 0);
secp256k1_fe_set_int(&r->z, 0);
}
static void secp256k1_gej_set_xy(secp256k1_gej_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y) {
r->infinity = 0;
r->x = *x;
r->y = *y;
secp256k1_fe_set_int(&r->z, 1);
}
static void secp256k1_gej_clear(secp256k1_gej_t *r) {
r->infinity = 0;
secp256k1_fe_clear(&r->x);
secp256k1_fe_clear(&r->y);
secp256k1_fe_clear(&r->z);
}
static void secp256k1_ge_clear(secp256k1_ge_t *r) {
r->infinity = 0;
secp256k1_fe_clear(&r->x);
secp256k1_fe_clear(&r->y);
}
static int secp256k1_ge_set_xo_var(secp256k1_ge_t *r, const secp256k1_fe_t *x, int odd) {
secp256k1_fe_t x2, x3, c;
r->x = *x;
secp256k1_fe_sqr(&x2, x);
secp256k1_fe_mul(&x3, x, &x2);
r->infinity = 0;
secp256k1_fe_set_int(&c, 7);
secp256k1_fe_add(&c, &x3);
if (!secp256k1_fe_sqrt_var(&r->y, &c)) {
return 0;
}
secp256k1_fe_normalize_var(&r->y);
if (secp256k1_fe_is_odd(&r->y) != odd) {
secp256k1_fe_negate(&r->y, &r->y, 1);
}
return 1;
}
static void secp256k1_gej_set_ge(secp256k1_gej_t *r, const secp256k1_ge_t *a) {
r->infinity = a->infinity;
r->x = a->x;
r->y = a->y;
secp256k1_fe_set_int(&r->z, 1);
}
static int secp256k1_gej_eq_x_var(const secp256k1_fe_t *x, const secp256k1_gej_t *a) {
secp256k1_fe_t r, r2;
VERIFY_CHECK(!a->infinity);
secp256k1_fe_sqr(&r, &a->z); secp256k1_fe_mul(&r, &r, x);
r2 = a->x; secp256k1_fe_normalize_weak(&r2);
return secp256k1_fe_equal_var(&r, &r2);
}
static void secp256k1_gej_neg(secp256k1_gej_t *r, const secp256k1_gej_t *a) {
r->infinity = a->infinity;
r->x = a->x;
r->y = a->y;
r->z = a->z;
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
static int secp256k1_gej_is_infinity(const secp256k1_gej_t *a) {
return a->infinity;
}
static int secp256k1_gej_is_valid_var(const secp256k1_gej_t *a) {
secp256k1_fe_t y2, x3, z2, z6;
if (a->infinity) {
return 0;
}
/** y^2 = x^3 + 7
* (Y/Z^3)^2 = (X/Z^2)^3 + 7
* Y^2 / Z^6 = X^3 / Z^6 + 7
* Y^2 = X^3 + 7*Z^6
*/
secp256k1_fe_sqr(&y2, &a->y);
secp256k1_fe_sqr(&x3, &a->x); secp256k1_fe_mul(&x3, &x3, &a->x);
secp256k1_fe_sqr(&z2, &a->z);
secp256k1_fe_sqr(&z6, &z2); secp256k1_fe_mul(&z6, &z6, &z2);
secp256k1_fe_mul_int(&z6, 7);
secp256k1_fe_add(&x3, &z6);
secp256k1_fe_normalize_weak(&x3);
return secp256k1_fe_equal_var(&y2, &x3);
}
static int secp256k1_ge_is_valid_var(const secp256k1_ge_t *a) {
secp256k1_fe_t y2, x3, c;
if (a->infinity) {
return 0;
}
/* y^2 = x^3 + 7 */
secp256k1_fe_sqr(&y2, &a->y);
secp256k1_fe_sqr(&x3, &a->x); secp256k1_fe_mul(&x3, &x3, &a->x);
secp256k1_fe_set_int(&c, 7);
secp256k1_fe_add(&x3, &c);
secp256k1_fe_normalize_weak(&x3);
return secp256k1_fe_equal_var(&y2, &x3);
}
static void secp256k1_gej_double_var(secp256k1_gej_t *r, const secp256k1_gej_t *a) {
/* Operations: 3 mul, 4 sqr, 0 normalize, 12 mul_int/add/negate */
secp256k1_fe_t t1,t2,t3,t4;
/** For secp256k1, 2Q is infinity if and only if Q is infinity. This is because if 2Q = infinity,
* Q must equal -Q, or that Q.y == -(Q.y), or Q.y is 0. For a point on y^2 = x^3 + 7 to have
* y=0, x^3 must be -7 mod p. However, -7 has no cube root mod p.
*/
r->infinity = a->infinity;
if (r->infinity) {
return;
}
secp256k1_fe_mul(&r->z, &a->z, &a->y);
secp256k1_fe_mul_int(&r->z, 2); /* Z' = 2*Y*Z (2) */
secp256k1_fe_sqr(&t1, &a->x);
secp256k1_fe_mul_int(&t1, 3); /* T1 = 3*X^2 (3) */
secp256k1_fe_sqr(&t2, &t1); /* T2 = 9*X^4 (1) */
secp256k1_fe_sqr(&t3, &a->y);
secp256k1_fe_mul_int(&t3, 2); /* T3 = 2*Y^2 (2) */
secp256k1_fe_sqr(&t4, &t3);
secp256k1_fe_mul_int(&t4, 2); /* T4 = 8*Y^4 (2) */
secp256k1_fe_mul(&t3, &t3, &a->x); /* T3 = 2*X*Y^2 (1) */
r->x = t3;
secp256k1_fe_mul_int(&r->x, 4); /* X' = 8*X*Y^2 (4) */
secp256k1_fe_negate(&r->x, &r->x, 4); /* X' = -8*X*Y^2 (5) */
secp256k1_fe_add(&r->x, &t2); /* X' = 9*X^4 - 8*X*Y^2 (6) */
secp256k1_fe_negate(&t2, &t2, 1); /* T2 = -9*X^4 (2) */
secp256k1_fe_mul_int(&t3, 6); /* T3 = 12*X*Y^2 (6) */
secp256k1_fe_add(&t3, &t2); /* T3 = 12*X*Y^2 - 9*X^4 (8) */
secp256k1_fe_mul(&r->y, &t1, &t3); /* Y' = 36*X^3*Y^2 - 27*X^6 (1) */
secp256k1_fe_negate(&t2, &t4, 2); /* T2 = -8*Y^4 (3) */
secp256k1_fe_add(&r->y, &t2); /* Y' = 36*X^3*Y^2 - 27*X^6 - 8*Y^4 (4) */
}
static void secp256k1_gej_add_var(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_gej_t *b) {
/* Operations: 12 mul, 4 sqr, 2 normalize, 12 mul_int/add/negate */
secp256k1_fe_t z22, z12, u1, u2, s1, s2, h, i, i2, h2, h3, t;
if (a->infinity) {
*r = *b;
return;
}
if (b->infinity) {
*r = *a;
return;
}
r->infinity = 0;
secp256k1_fe_sqr(&z22, &b->z);
secp256k1_fe_sqr(&z12, &a->z);
secp256k1_fe_mul(&u1, &a->x, &z22);
secp256k1_fe_mul(&u2, &b->x, &z12);
secp256k1_fe_mul(&s1, &a->y, &z22); secp256k1_fe_mul(&s1, &s1, &b->z);
secp256k1_fe_mul(&s2, &b->y, &z12); secp256k1_fe_mul(&s2, &s2, &a->z);
secp256k1_fe_negate(&h, &u1, 1); secp256k1_fe_add(&h, &u2);
secp256k1_fe_negate(&i, &s1, 1); secp256k1_fe_add(&i, &s2);
if (secp256k1_fe_normalizes_to_zero_var(&h)) {
if (secp256k1_fe_normalizes_to_zero_var(&i)) {
secp256k1_gej_double_var(r, a);
} else {
r->infinity = 1;
}
return;
}
secp256k1_fe_sqr(&i2, &i);
secp256k1_fe_sqr(&h2, &h);
secp256k1_fe_mul(&h3, &h, &h2);
secp256k1_fe_mul(&r->z, &a->z, &b->z); secp256k1_fe_mul(&r->z, &r->z, &h);
secp256k1_fe_mul(&t, &u1, &h2);
r->x = t; secp256k1_fe_mul_int(&r->x, 2); secp256k1_fe_add(&r->x, &h3); secp256k1_fe_negate(&r->x, &r->x, 3); secp256k1_fe_add(&r->x, &i2);
secp256k1_fe_negate(&r->y, &r->x, 5); secp256k1_fe_add(&r->y, &t); secp256k1_fe_mul(&r->y, &r->y, &i);
secp256k1_fe_mul(&h3, &h3, &s1); secp256k1_fe_negate(&h3, &h3, 1);
secp256k1_fe_add(&r->y, &h3);
}
static void secp256k1_gej_add_ge_var(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_ge_t *b) {
/* 8 mul, 3 sqr, 4 normalize, 12 mul_int/add/negate */
secp256k1_fe_t z12, u1, u2, s1, s2, h, i, i2, h2, h3, t;
if (a->infinity) {
r->infinity = b->infinity;
r->x = b->x;
r->y = b->y;
secp256k1_fe_set_int(&r->z, 1);
return;
}
if (b->infinity) {
*r = *a;
return;
}
r->infinity = 0;
secp256k1_fe_sqr(&z12, &a->z);
u1 = a->x; secp256k1_fe_normalize_weak(&u1);
secp256k1_fe_mul(&u2, &b->x, &z12);
s1 = a->y; secp256k1_fe_normalize_weak(&s1);
secp256k1_fe_mul(&s2, &b->y, &z12); secp256k1_fe_mul(&s2, &s2, &a->z);
secp256k1_fe_negate(&h, &u1, 1); secp256k1_fe_add(&h, &u2);
secp256k1_fe_negate(&i, &s1, 1); secp256k1_fe_add(&i, &s2);
if (secp256k1_fe_normalizes_to_zero_var(&h)) {
if (secp256k1_fe_normalizes_to_zero_var(&i)) {
secp256k1_gej_double_var(r, a);
} else {
r->infinity = 1;
}
return;
}
secp256k1_fe_sqr(&i2, &i);
secp256k1_fe_sqr(&h2, &h);
secp256k1_fe_mul(&h3, &h, &h2);
r->z = a->z; secp256k1_fe_mul(&r->z, &r->z, &h);
secp256k1_fe_mul(&t, &u1, &h2);
r->x = t; secp256k1_fe_mul_int(&r->x, 2); secp256k1_fe_add(&r->x, &h3); secp256k1_fe_negate(&r->x, &r->x, 3); secp256k1_fe_add(&r->x, &i2);
secp256k1_fe_negate(&r->y, &r->x, 5); secp256k1_fe_add(&r->y, &t); secp256k1_fe_mul(&r->y, &r->y, &i);
secp256k1_fe_mul(&h3, &h3, &s1); secp256k1_fe_negate(&h3, &h3, 1);
secp256k1_fe_add(&r->y, &h3);
}
static void secp256k1_gej_add_ge(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_ge_t *b) {
/* Operations: 7 mul, 5 sqr, 5 normalize, 19 mul_int/add/negate */
secp256k1_fe_t zz, u1, u2, s1, s2, z, t, m, n, q, rr;
int infinity;
VERIFY_CHECK(!b->infinity);
VERIFY_CHECK(a->infinity == 0 || a->infinity == 1);
/** In:
* Eric Brier and Marc Joye, Weierstrass Elliptic Curves and Side-Channel Attacks.
* In D. Naccache and P. Paillier, Eds., Public Key Cryptography, vol. 2274 of Lecture Notes in Computer Science, pages 335-345. Springer-Verlag, 2002.
* we find as solution for a unified addition/doubling formula:
* lambda = ((x1 + x2)^2 - x1 * x2 + a) / (y1 + y2), with a = 0 for secp256k1's curve equation.
* x3 = lambda^2 - (x1 + x2)
* 2*y3 = lambda * (x1 + x2 - 2 * x3) - (y1 + y2).
*
* Substituting x_i = Xi / Zi^2 and yi = Yi / Zi^3, for i=1,2,3, gives:
* U1 = X1*Z2^2, U2 = X2*Z1^2
* S1 = Y1*Z2^3, S2 = Y2*Z1^3
* Z = Z1*Z2
* T = U1+U2
* M = S1+S2
* Q = T*M^2
* R = T^2-U1*U2
* X3 = 4*(R^2-Q)
* Y3 = 4*(R*(3*Q-2*R^2)-M^4)
* Z3 = 2*M*Z
* (Note that the paper uses xi = Xi / Zi and yi = Yi / Zi instead.)
*/
secp256k1_fe_sqr(&zz, &a->z); /* z = Z1^2 */
u1 = a->x; secp256k1_fe_normalize_weak(&u1); /* u1 = U1 = X1*Z2^2 (1) */
secp256k1_fe_mul(&u2, &b->x, &zz); /* u2 = U2 = X2*Z1^2 (1) */
s1 = a->y; secp256k1_fe_normalize_weak(&s1); /* s1 = S1 = Y1*Z2^3 (1) */
secp256k1_fe_mul(&s2, &b->y, &zz); /* s2 = Y2*Z2^2 (1) */
secp256k1_fe_mul(&s2, &s2, &a->z); /* s2 = S2 = Y2*Z1^3 (1) */
z = a->z; /* z = Z = Z1*Z2 (8) */
t = u1; secp256k1_fe_add(&t, &u2); /* t = T = U1+U2 (2) */
m = s1; secp256k1_fe_add(&m, &s2); /* m = M = S1+S2 (2) */
secp256k1_fe_sqr(&n, &m); /* n = M^2 (1) */
secp256k1_fe_mul(&q, &n, &t); /* q = Q = T*M^2 (1) */
secp256k1_fe_sqr(&n, &n); /* n = M^4 (1) */
secp256k1_fe_sqr(&rr, &t); /* rr = T^2 (1) */
secp256k1_fe_mul(&t, &u1, &u2); secp256k1_fe_negate(&t, &t, 1); /* t = -U1*U2 (2) */
secp256k1_fe_add(&rr, &t); /* rr = R = T^2-U1*U2 (3) */
secp256k1_fe_sqr(&t, &rr); /* t = R^2 (1) */
secp256k1_fe_mul(&r->z, &m, &z); /* r->z = M*Z (1) */
infinity = secp256k1_fe_normalizes_to_zero(&r->z) * (1 - a->infinity);
secp256k1_fe_mul_int(&r->z, 2 * (1 - a->infinity)); /* r->z = Z3 = 2*M*Z (2) */
r->x = t; /* r->x = R^2 (1) */
secp256k1_fe_negate(&q, &q, 1); /* q = -Q (2) */
secp256k1_fe_add(&r->x, &q); /* r->x = R^2-Q (3) */
secp256k1_fe_normalize(&r->x);
secp256k1_fe_mul_int(&q, 3); /* q = -3*Q (6) */
secp256k1_fe_mul_int(&t, 2); /* t = 2*R^2 (2) */
secp256k1_fe_add(&t, &q); /* t = 2*R^2-3*Q (8) */
secp256k1_fe_mul(&t, &t, &rr); /* t = R*(2*R^2-3*Q) (1) */
secp256k1_fe_add(&t, &n); /* t = R*(2*R^2-3*Q)+M^4 (2) */
secp256k1_fe_negate(&r->y, &t, 2); /* r->y = R*(3*Q-2*R^2)-M^4 (3) */
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_mul_int(&r->x, 4 * (1 - a->infinity)); /* r->x = X3 = 4*(R^2-Q) */
secp256k1_fe_mul_int(&r->y, 4 * (1 - a->infinity)); /* r->y = Y3 = 4*R*(3*Q-2*R^2)-4*M^4 (4) */
/** In case a->infinity == 1, the above code results in r->x, r->y, and r->z all equal to 0.
* Add b->x to x, b->y to y, and 1 to z in that case.
*/
t = b->x; secp256k1_fe_mul_int(&t, a->infinity);
secp256k1_fe_add(&r->x, &t);
t = b->y; secp256k1_fe_mul_int(&t, a->infinity);
secp256k1_fe_add(&r->y, &t);
secp256k1_fe_set_int(&t, a->infinity);
secp256k1_fe_add(&r->z, &t);
r->infinity = infinity;
}
static void secp256k1_ge_to_storage(secp256k1_ge_storage_t *r, const secp256k1_ge_t *a) {
secp256k1_fe_t x, y;
VERIFY_CHECK(!a->infinity);
x = a->x;
secp256k1_fe_normalize(&x);
y = a->y;
secp256k1_fe_normalize(&y);
secp256k1_fe_to_storage(&r->x, &x);
secp256k1_fe_to_storage(&r->y, &y);
}
static void secp256k1_ge_from_storage(secp256k1_ge_t *r, const secp256k1_ge_storage_t *a) {
secp256k1_fe_from_storage(&r->x, &a->x);
secp256k1_fe_from_storage(&r->y, &a->y);
r->infinity = 0;
}
static SECP256K1_INLINE void secp256k1_ge_storage_cmov(secp256k1_ge_storage_t *r, const secp256k1_ge_storage_t *a, int flag) {
secp256k1_fe_storage_cmov(&r->x, &a->x, flag);
secp256k1_fe_storage_cmov(&r->y, &a->y, flag);
}
#ifdef USE_ENDOMORPHISM
static void secp256k1_gej_mul_lambda(secp256k1_gej_t *r, const secp256k1_gej_t *a) {
static const secp256k1_fe_t beta = SECP256K1_FE_CONST(
0x7ae96a2bul, 0x657c0710ul, 0x6e64479eul, 0xac3434e9ul,
0x9cf04975ul, 0x12f58995ul, 0xc1396c28ul, 0x719501eeul
);
*r = *a;
secp256k1_fe_mul(&r->x, &r->x, &beta);
}
#endif
#endif

@ -1,93 +0,0 @@
/**********************************************************************
* Copyright (c) 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_SCALAR_
#define _SECP256K1_SCALAR_
#include "num.h"
#if defined HAVE_CONFIG_H
#include "libsecp256k1-config.h"
#endif
#if defined(USE_SCALAR_4X64)
#include "scalar_4x64.h"
#elif defined(USE_SCALAR_8X32)
#include "scalar_8x32.h"
#else
#error "Please select scalar implementation"
#endif
/** Clear a scalar to prevent the leak of sensitive data. */
static void secp256k1_scalar_clear(secp256k1_scalar_t *r);
/** Access bits from a scalar. All requested bits must belong to the same 32-bit limb. */
static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count);
/** Access bits from a scalar. Not constant time. */
static unsigned int secp256k1_scalar_get_bits_var(const secp256k1_scalar_t *a, unsigned int offset, unsigned int count);
/** Set a scalar from a big endian byte array. */
static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char *bin, int *overflow);
/** Set a scalar to an unsigned integer. */
static void secp256k1_scalar_set_int(secp256k1_scalar_t *r, unsigned int v);
/** Convert a scalar to a byte array. */
static void secp256k1_scalar_get_b32(unsigned char *bin, const secp256k1_scalar_t* a);
/** Add two scalars together (modulo the group order). Returns whether it overflowed. */
static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b);
/** Add a power of two to a scalar. The result is not allowed to overflow. */
static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit);
/** Multiply two scalars (modulo the group order). */
static void secp256k1_scalar_mul(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b);
/** Compute the square of a scalar (modulo the group order). */
static void secp256k1_scalar_sqr(secp256k1_scalar_t *r, const secp256k1_scalar_t *a);
/** Compute the inverse of a scalar (modulo the group order). */
static void secp256k1_scalar_inverse(secp256k1_scalar_t *r, const secp256k1_scalar_t *a);
/** Compute the inverse of a scalar (modulo the group order), without constant-time guarantee. */
static void secp256k1_scalar_inverse_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *a);
/** Compute the complement of a scalar (modulo the group order). */
static void secp256k1_scalar_negate(secp256k1_scalar_t *r, const secp256k1_scalar_t *a);
/** Check whether a scalar equals zero. */
static int secp256k1_scalar_is_zero(const secp256k1_scalar_t *a);
/** Check whether a scalar equals one. */
static int secp256k1_scalar_is_one(const secp256k1_scalar_t *a);
/** Check whether a scalar is higher than the group order divided by 2. */
static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a);
#ifndef USE_NUM_NONE
/** Convert a scalar to a number. */
static void secp256k1_scalar_get_num(secp256k1_num_t *r, const secp256k1_scalar_t *a);
/** Get the order of the group as a number. */
static void secp256k1_scalar_order_get_num(secp256k1_num_t *r);
#endif
/** Compare two scalars. */
static int secp256k1_scalar_eq(const secp256k1_scalar_t *a, const secp256k1_scalar_t *b);
#ifdef USE_ENDOMORPHISM
/** Find r1 and r2 such that r1+r2*2^128 = a. */
static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a);
/** Find r1 and r2 such that r1+r2*lambda = a, and r1 and r2 are maximum 128 bits long (see secp256k1_gej_mul_lambda). */
static void secp256k1_scalar_split_lambda_var(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a);
#endif
/** Multiply a and b (without taking the modulus!), divide by 2**shift, and round to the nearest integer. Shift must be at least 256. */
static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b, unsigned int shift);
#endif

@ -1,372 +0,0 @@
/**********************************************************************
* Copyright (c) 2013, 2014 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#define SECP256K1_BUILD (1)
#include "include/secp256k1.h"
#include "util.h"
#include "num_impl.h"
#include "field_impl.h"
#include "scalar_impl.h"
#include "group_impl.h"
#include "ecmult_impl.h"
#include "ecmult_gen_impl.h"
#include "ecdsa_impl.h"
#include "eckey_impl.h"
#include "hash_impl.h"
void secp256k1_start(unsigned int flags) {
if (flags & SECP256K1_START_SIGN) {
secp256k1_ecmult_gen_start();
}
if (flags & SECP256K1_START_VERIFY) {
secp256k1_ecmult_start();
}
}
void secp256k1_stop(void) {
secp256k1_ecmult_stop();
secp256k1_ecmult_gen_stop();
}
int secp256k1_ecdsa_verify(const unsigned char *msg32, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen) {
secp256k1_ge_t q;
secp256k1_ecdsa_sig_t s;
secp256k1_scalar_t m;
int ret = -3;
DEBUG_CHECK(secp256k1_ecmult_consts != NULL);
DEBUG_CHECK(msg32 != NULL);
DEBUG_CHECK(sig != NULL);
DEBUG_CHECK(pubkey != NULL);
secp256k1_scalar_set_b32(&m, msg32, NULL);
if (secp256k1_eckey_pubkey_parse(&q, pubkey, pubkeylen)) {
if (secp256k1_ecdsa_sig_parse(&s, sig, siglen)) {
if (secp256k1_ecdsa_sig_verify(&s, &q, &m)) {
/* success is 1, all other values are fail */
ret = 1;
} else {
ret = 0;
}
} else {
ret = -2;
}
} else {
ret = -1;
}
return ret;
}
static int nonce_function_rfc6979(unsigned char *nonce32, const unsigned char *msg32, const unsigned char *key32, unsigned int counter, const void *data) {
secp256k1_rfc6979_hmac_sha256_t rng;
unsigned int i;
secp256k1_rfc6979_hmac_sha256_initialize(&rng, key32, 32, msg32, 32, (const unsigned char*)data, data != NULL ? 32 : 0);
for (i = 0; i <= counter; i++) {
secp256k1_rfc6979_hmac_sha256_generate(&rng, nonce32, 32);
}
secp256k1_rfc6979_hmac_sha256_finalize(&rng);
return 1;
}
const secp256k1_nonce_function_t secp256k1_nonce_function_rfc6979 = nonce_function_rfc6979;
const secp256k1_nonce_function_t secp256k1_nonce_function_default = nonce_function_rfc6979;
int secp256k1_ecdsa_sign(const unsigned char *msg32, unsigned char *signature, int *signaturelen, const unsigned char *seckey, secp256k1_nonce_function_t noncefp, const void* noncedata) {
secp256k1_ecdsa_sig_t sig;
secp256k1_scalar_t sec, non, msg;
int ret = 0;
int overflow = 0;
unsigned int count = 0;
DEBUG_CHECK(secp256k1_ecmult_gen_consts != NULL);
DEBUG_CHECK(msg32 != NULL);
DEBUG_CHECK(signature != NULL);
DEBUG_CHECK(signaturelen != NULL);
DEBUG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
/* Fail if the secret key is invalid. */
if (!overflow && !secp256k1_scalar_is_zero(&sec)) {
secp256k1_scalar_set_b32(&msg, msg32, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, msg32, seckey, count, noncedata);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_ecdsa_sig_sign(&sig, &sec, &msg, &non, NULL)) {
break;
}
}
count++;
}
if (ret) {
ret = secp256k1_ecdsa_sig_serialize(signature, signaturelen, &sig);
}
secp256k1_scalar_clear(&msg);
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
}
if (!ret) {
*signaturelen = 0;
}
return ret;
}
int secp256k1_ecdsa_sign_compact(const unsigned char *msg32, unsigned char *sig64, const unsigned char *seckey, secp256k1_nonce_function_t noncefp, const void* noncedata, int *recid) {
secp256k1_ecdsa_sig_t sig;
secp256k1_scalar_t sec, non, msg;
int ret = 0;
int overflow = 0;
unsigned int count = 0;
DEBUG_CHECK(secp256k1_ecmult_gen_consts != NULL);
DEBUG_CHECK(msg32 != NULL);
DEBUG_CHECK(sig64 != NULL);
DEBUG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
/* Fail if the secret key is invalid. */
if (!overflow && !secp256k1_scalar_is_zero(&sec)) {
secp256k1_scalar_set_b32(&msg, msg32, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, msg32, seckey, count, noncedata);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_ecdsa_sig_sign(&sig, &sec, &msg, &non, recid)) {
break;
}
}
count++;
}
if (ret) {
secp256k1_scalar_get_b32(sig64, &sig.r);
secp256k1_scalar_get_b32(sig64 + 32, &sig.s);
}
secp256k1_scalar_clear(&msg);
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
}
if (!ret) {
memset(sig64, 0, 64);
}
return ret;
}
int secp256k1_ecdsa_recover_compact(const unsigned char *msg32, const unsigned char *sig64, unsigned char *pubkey, int *pubkeylen, int compressed, int recid) {
secp256k1_ge_t q;
secp256k1_ecdsa_sig_t sig;
secp256k1_scalar_t m;
int ret = 0;
int overflow = 0;
DEBUG_CHECK(secp256k1_ecmult_consts != NULL);
DEBUG_CHECK(msg32 != NULL);
DEBUG_CHECK(sig64 != NULL);
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(pubkeylen != NULL);
DEBUG_CHECK(recid >= 0 && recid <= 3);
secp256k1_scalar_set_b32(&sig.r, sig64, &overflow);
if (!overflow) {
secp256k1_scalar_set_b32(&sig.s, sig64 + 32, &overflow);
if (!overflow) {
secp256k1_scalar_set_b32(&m, msg32, NULL);
if (secp256k1_ecdsa_sig_recover(&sig, &q, &m, recid)) {
ret = secp256k1_eckey_pubkey_serialize(&q, pubkey, pubkeylen, compressed);
}
}
}
return ret;
}
int secp256k1_ec_seckey_verify(const unsigned char *seckey) {
secp256k1_scalar_t sec;
int ret;
int overflow;
DEBUG_CHECK(seckey != NULL);
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
ret = !secp256k1_scalar_is_zero(&sec) && !overflow;
secp256k1_scalar_clear(&sec);
return ret;
}
int secp256k1_ec_pubkey_verify(const unsigned char *pubkey, int pubkeylen) {
secp256k1_ge_t q;
DEBUG_CHECK(pubkey != NULL);
return secp256k1_eckey_pubkey_parse(&q, pubkey, pubkeylen);
}
int secp256k1_ec_pubkey_create(unsigned char *pubkey, int *pubkeylen, const unsigned char *seckey, int compressed) {
secp256k1_gej_t pj;
secp256k1_ge_t p;
secp256k1_scalar_t sec;
int overflow;
int ret = 0;
DEBUG_CHECK(secp256k1_ecmult_gen_consts != NULL);
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(pubkeylen != NULL);
DEBUG_CHECK(seckey != NULL);
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
if (!overflow) {
secp256k1_ecmult_gen(&pj, &sec);
secp256k1_scalar_clear(&sec);
secp256k1_ge_set_gej(&p, &pj);
ret = secp256k1_eckey_pubkey_serialize(&p, pubkey, pubkeylen, compressed);
}
if (!ret) {
*pubkeylen = 0;
}
return ret;
}
int secp256k1_ec_pubkey_decompress(unsigned char *pubkey, int *pubkeylen) {
secp256k1_ge_t p;
int ret = 0;
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(pubkeylen != NULL);
if (secp256k1_eckey_pubkey_parse(&p, pubkey, *pubkeylen)) {
ret = secp256k1_eckey_pubkey_serialize(&p, pubkey, pubkeylen, 0);
}
return ret;
}
int secp256k1_ec_privkey_tweak_add(unsigned char *seckey, const unsigned char *tweak) {
secp256k1_scalar_t term;
secp256k1_scalar_t sec;
int ret = 0;
int overflow = 0;
DEBUG_CHECK(seckey != NULL);
DEBUG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&term, tweak, &overflow);
secp256k1_scalar_set_b32(&sec, seckey, NULL);
ret = secp256k1_eckey_privkey_tweak_add(&sec, &term) && !overflow;
if (ret) {
secp256k1_scalar_get_b32(seckey, &sec);
}
secp256k1_scalar_clear(&sec);
secp256k1_scalar_clear(&term);
return ret;
}
int secp256k1_ec_pubkey_tweak_add(unsigned char *pubkey, int pubkeylen, const unsigned char *tweak) {
secp256k1_ge_t p;
secp256k1_scalar_t term;
int ret = 0;
int overflow = 0;
DEBUG_CHECK(secp256k1_ecmult_consts != NULL);
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&term, tweak, &overflow);
if (!overflow) {
ret = secp256k1_eckey_pubkey_parse(&p, pubkey, pubkeylen);
if (ret) {
ret = secp256k1_eckey_pubkey_tweak_add(&p, &term);
}
if (ret) {
int oldlen = pubkeylen;
ret = secp256k1_eckey_pubkey_serialize(&p, pubkey, &pubkeylen, oldlen <= 33);
VERIFY_CHECK(pubkeylen == oldlen);
}
}
return ret;
}
int secp256k1_ec_privkey_tweak_mul(unsigned char *seckey, const unsigned char *tweak) {
secp256k1_scalar_t factor;
secp256k1_scalar_t sec;
int ret = 0;
int overflow = 0;
DEBUG_CHECK(seckey != NULL);
DEBUG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&factor, tweak, &overflow);
secp256k1_scalar_set_b32(&sec, seckey, NULL);
ret = secp256k1_eckey_privkey_tweak_mul(&sec, &factor) && !overflow;
if (ret) {
secp256k1_scalar_get_b32(seckey, &sec);
}
secp256k1_scalar_clear(&sec);
secp256k1_scalar_clear(&factor);
return ret;
}
int secp256k1_ec_pubkey_tweak_mul(unsigned char *pubkey, int pubkeylen, const unsigned char *tweak) {
secp256k1_ge_t p;
secp256k1_scalar_t factor;
int ret = 0;
int overflow = 0;
DEBUG_CHECK(secp256k1_ecmult_consts != NULL);
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(tweak != NULL);
secp256k1_scalar_set_b32(&factor, tweak, &overflow);
if (!overflow) {
ret = secp256k1_eckey_pubkey_parse(&p, pubkey, pubkeylen);
if (ret) {
ret = secp256k1_eckey_pubkey_tweak_mul(&p, &factor);
}
if (ret) {
int oldlen = pubkeylen;
ret = secp256k1_eckey_pubkey_serialize(&p, pubkey, &pubkeylen, oldlen <= 33);
VERIFY_CHECK(pubkeylen == oldlen);
}
}
return ret;
}
int secp256k1_ec_privkey_export(const unsigned char *seckey, unsigned char *privkey, int *privkeylen, int compressed) {
secp256k1_scalar_t key;
int ret = 0;
DEBUG_CHECK(seckey != NULL);
DEBUG_CHECK(privkey != NULL);
DEBUG_CHECK(privkeylen != NULL);
secp256k1_scalar_set_b32(&key, seckey, NULL);
ret = secp256k1_eckey_privkey_serialize(privkey, privkeylen, &key, compressed);
secp256k1_scalar_clear(&key);
return ret;
}
int secp256k1_ec_privkey_import(unsigned char *seckey, const unsigned char *privkey, int privkeylen) {
secp256k1_scalar_t key;
int ret = 0;
DEBUG_CHECK(seckey != NULL);
DEBUG_CHECK(privkey != NULL);
ret = secp256k1_eckey_privkey_parse(&key, privkey, privkeylen);
if (ret) {
secp256k1_scalar_get_b32(seckey, &key);
}
secp256k1_scalar_clear(&key);
return ret;
}
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