forked from mirror/go-ethereum
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
548 lines
24 KiB
548 lines
24 KiB
9 years ago
|
#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
|