headrush
/
go-ethereum
forked from mirror/go-ethereum
1
1
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

crypto/sha3: Delete old copied code

Browse Source
release/1.4
Ricardo Catalinas Jiménez 9 years ago
parent f8d98f7fcd
commit 0a1da69fac
2 changed files with 0 additions and 671 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 434
      crypto/sha3/keccakf.go
  2. 237
      crypto/sha3/sha3.go

434
crypto/sha3/keccakf.go
Unescape View File

@ -1,434 +0,0 @@
// Copyright 2014 The Go Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
package sha3
// rc stores the round constants for use in the ι step.
var rc = [24]uint64{
0x0000000000000001,
0x0000000000008082,
0x800000000000808A,
0x8000000080008000,
0x000000000000808B,
0x0000000080000001,
0x8000000080008081,
0x8000000000008009,
0x000000000000008A,
0x0000000000000088,
0x0000000080008009,
0x000000008000000A,
0x000000008000808B,
0x800000000000008B,
0x8000000000008089,
0x8000000000008003,
0x8000000000008002,
0x8000000000000080,
0x000000000000800A,
0x800000008000000A,
0x8000000080008081,
0x8000000000008080,
0x0000000080000001,
0x8000000080008008,
}
// keccakF1600 applies the Keccak permutation to a 1600b-wide
// state represented as a slice of 25 uint64s.
func keccakF1600(a *[25]uint64) {
// Implementation translated from Keccak-inplace.c
// in the keccak reference code.
var t, bc0, bc1, bc2, bc3, bc4, d0, d1, d2, d3, d4 uint64
for i := 0; i < 24; i += 4 {
// Combines the 5 steps in each round into 2 steps.
// Unrolls 4 rounds per loop and spreads some steps across rounds.
// Round 1
bc0 = a[0] ^ a[5] ^ a[10] ^ a[15] ^ a[20]
bc1 = a[1] ^ a[6] ^ a[11] ^ a[16] ^ a[21]
bc2 = a[2] ^ a[7] ^ a[12] ^ a[17] ^ a[22]
bc3 = a[3] ^ a[8] ^ a[13] ^ a[18] ^ a[23]
bc4 = a[4] ^ a[9] ^ a[14] ^ a[19] ^ a[24]
d0 = bc4 ^ (bc1<<1 | bc1>>63)
d1 = bc0 ^ (bc2<<1 | bc2>>63)
d2 = bc1 ^ (bc3<<1 | bc3>>63)
d3 = bc2 ^ (bc4<<1 | bc4>>63)
d4 = bc3 ^ (bc0<<1 | bc0>>63)
bc0 = a[0] ^ d0
t = a[6] ^ d1
bc1 = t<<44 | t>>(64-44)
t = a[12] ^ d2
bc2 = t<<43 | t>>(64-43)
t = a[18] ^ d3
bc3 = t<<21 | t>>(64-21)
t = a[24] ^ d4
bc4 = t<<14 | t>>(64-14)
a[0] = bc0 ^ (bc2 &^ bc1) ^ rc[i]
a[6] = bc1 ^ (bc3 &^ bc2)
a[12] = bc2 ^ (bc4 &^ bc3)
a[18] = bc3 ^ (bc0 &^ bc4)
a[24] = bc4 ^ (bc1 &^ bc0)
t = a[10] ^ d0
bc2 = t<<3 | t>>(64-3)
t = a[16] ^ d1
bc3 = t<<45 | t>>(64-45)
t = a[22] ^ d2
bc4 = t<<61 | t>>(64-61)
t = a[3] ^ d3
bc0 = t<<28 | t>>(64-28)
t = a[9] ^ d4
bc1 = t<<20 | t>>(64-20)
a[10] = bc0 ^ (bc2 &^ bc1)
a[16] = bc1 ^ (bc3 &^ bc2)
a[22] = bc2 ^ (bc4 &^ bc3)
a[3] = bc3 ^ (bc0 &^ bc4)
a[9] = bc4 ^ (bc1 &^ bc0)
t = a[20] ^ d0
bc4 = t<<18 | t>>(64-18)
t = a[1] ^ d1
bc0 = t<<1 | t>>(64-1)
t = a[7] ^ d2
bc1 = t<<6 | t>>(64-6)
t = a[13] ^ d3
bc2 = t<<25 | t>>(64-25)
t = a[19] ^ d4
bc3 = t<<8 | t>>(64-8)
a[20] = bc0 ^ (bc2 &^ bc1)
a[1] = bc1 ^ (bc3 &^ bc2)
a[7] = bc2 ^ (bc4 &^ bc3)
a[13] = bc3 ^ (bc0 &^ bc4)
a[19] = bc4 ^ (bc1 &^ bc0)
t = a[5] ^ d0
bc1 = t<<36 | t>>(64-36)
t = a[11] ^ d1
bc2 = t<<10 | t>>(64-10)
t = a[17] ^ d2
bc3 = t<<15 | t>>(64-15)
t = a[23] ^ d3
bc4 = t<<56 | t>>(64-56)
t = a[4] ^ d4
bc0 = t<<27 | t>>(64-27)
a[5] = bc0 ^ (bc2 &^ bc1)
a[11] = bc1 ^ (bc3 &^ bc2)
a[17] = bc2 ^ (bc4 &^ bc3)
a[23] = bc3 ^ (bc0 &^ bc4)
a[4] = bc4 ^ (bc1 &^ bc0)
t = a[15] ^ d0
bc3 = t<<41 | t>>(64-41)
t = a[21] ^ d1
bc4 = t<<2 | t>>(64-2)
t = a[2] ^ d2
bc0 = t<<62 | t>>(64-62)
t = a[8] ^ d3
bc1 = t<<55 | t>>(64-55)
t = a[14] ^ d4
bc2 = t<<39 | t>>(64-39)
a[15] = bc0 ^ (bc2 &^ bc1)
a[21] = bc1 ^ (bc3 &^ bc2)
a[2] = bc2 ^ (bc4 &^ bc3)
a[8] = bc3 ^ (bc0 &^ bc4)
a[14] = bc4 ^ (bc1 &^ bc0)
// Round 2
bc0 = a[0] ^ a[5] ^ a[10] ^ a[15] ^ a[20]
bc1 = a[1] ^ a[6] ^ a[11] ^ a[16] ^ a[21]
bc2 = a[2] ^ a[7] ^ a[12] ^ a[17] ^ a[22]
bc3 = a[3] ^ a[8] ^ a[13] ^ a[18] ^ a[23]
bc4 = a[4] ^ a[9] ^ a[14] ^ a[19] ^ a[24]
d0 = bc4 ^ (bc1<<1 | bc1>>63)
d1 = bc0 ^ (bc2<<1 | bc2>>63)
d2 = bc1 ^ (bc3<<1 | bc3>>63)
d3 = bc2 ^ (bc4<<1 | bc4>>63)
d4 = bc3 ^ (bc0<<1 | bc0>>63)
bc0 = a[0] ^ d0
t = a[16] ^ d1
bc1 = t<<44 | t>>(64-44)
t = a[7] ^ d2
bc2 = t<<43 | t>>(64-43)
t = a[23] ^ d3
bc3 = t<<21 | t>>(64-21)
t = a[14] ^ d4
bc4 = t<<14 | t>>(64-14)
a[0] = bc0 ^ (bc2 &^ bc1) ^ rc[i+1]
a[16] = bc1 ^ (bc3 &^ bc2)
a[7] = bc2 ^ (bc4 &^ bc3)
a[23] = bc3 ^ (bc0 &^ bc4)
a[14] = bc4 ^ (bc1 &^ bc0)
t = a[20] ^ d0
bc2 = t<<3 | t>>(64-3)
t = a[11] ^ d1
bc3 = t<<45 | t>>(64-45)
t = a[2] ^ d2
bc4 = t<<61 | t>>(64-61)
t = a[18] ^ d3
bc0 = t<<28 | t>>(64-28)
t = a[9] ^ d4
bc1 = t<<20 | t>>(64-20)
a[20] = bc0 ^ (bc2 &^ bc1)
a[11] = bc1 ^ (bc3 &^ bc2)
a[2] = bc2 ^ (bc4 &^ bc3)
a[18] = bc3 ^ (bc0 &^ bc4)
a[9] = bc4 ^ (bc1 &^ bc0)
t = a[15] ^ d0
bc4 = t<<18 | t>>(64-18)
t = a[6] ^ d1
bc0 = t<<1 | t>>(64-1)
t = a[22] ^ d2
bc1 = t<<6 | t>>(64-6)
t = a[13] ^ d3
bc2 = t<<25 | t>>(64-25)
t = a[4] ^ d4
bc3 = t<<8 | t>>(64-8)
a[15] = bc0 ^ (bc2 &^ bc1)
a[6] = bc1 ^ (bc3 &^ bc2)
a[22] = bc2 ^ (bc4 &^ bc3)
a[13] = bc3 ^ (bc0 &^ bc4)
a[4] = bc4 ^ (bc1 &^ bc0)
t = a[10] ^ d0
bc1 = t<<36 | t>>(64-36)
t = a[1] ^ d1
bc2 = t<<10 | t>>(64-10)
t = a[17] ^ d2
bc3 = t<<15 | t>>(64-15)
t = a[8] ^ d3
bc4 = t<<56 | t>>(64-56)
t = a[24] ^ d4
bc0 = t<<27 | t>>(64-27)
a[10] = bc0 ^ (bc2 &^ bc1)
a[1] = bc1 ^ (bc3 &^ bc2)
a[17] = bc2 ^ (bc4 &^ bc3)
a[8] = bc3 ^ (bc0 &^ bc4)
a[24] = bc4 ^ (bc1 &^ bc0)
t = a[5] ^ d0
bc3 = t<<41 | t>>(64-41)
t = a[21] ^ d1
bc4 = t<<2 | t>>(64-2)
t = a[12] ^ d2
bc0 = t<<62 | t>>(64-62)
t = a[3] ^ d3
bc1 = t<<55 | t>>(64-55)
t = a[19] ^ d4
bc2 = t<<39 | t>>(64-39)
a[5] = bc0 ^ (bc2 &^ bc1)
a[21] = bc1 ^ (bc3 &^ bc2)
a[12] = bc2 ^ (bc4 &^ bc3)
a[3] = bc3 ^ (bc0 &^ bc4)
a[19] = bc4 ^ (bc1 &^ bc0)
// Round 3
bc0 = a[0] ^ a[5] ^ a[10] ^ a[15] ^ a[20]
bc1 = a[1] ^ a[6] ^ a[11] ^ a[16] ^ a[21]
bc2 = a[2] ^ a[7] ^ a[12] ^ a[17] ^ a[22]
bc3 = a[3] ^ a[8] ^ a[13] ^ a[18] ^ a[23]
bc4 = a[4] ^ a[9] ^ a[14] ^ a[19] ^ a[24]
d0 = bc4 ^ (bc1<<1 | bc1>>63)
d1 = bc0 ^ (bc2<<1 | bc2>>63)
d2 = bc1 ^ (bc3<<1 | bc3>>63)
d3 = bc2 ^ (bc4<<1 | bc4>>63)
d4 = bc3 ^ (bc0<<1 | bc0>>63)
bc0 = a[0] ^ d0
t = a[11] ^ d1
bc1 = t<<44 | t>>(64-44)
t = a[22] ^ d2
bc2 = t<<43 | t>>(64-43)
t = a[8] ^ d3
bc3 = t<<21 | t>>(64-21)
t = a[19] ^ d4
bc4 = t<<14 | t>>(64-14)
a[0] = bc0 ^ (bc2 &^ bc1) ^ rc[i+2]
a[11] = bc1 ^ (bc3 &^ bc2)
a[22] = bc2 ^ (bc4 &^ bc3)
a[8] = bc3 ^ (bc0 &^ bc4)
a[19] = bc4 ^ (bc1 &^ bc0)
t = a[15] ^ d0
bc2 = t<<3 | t>>(64-3)
t = a[1] ^ d1
bc3 = t<<45 | t>>(64-45)
t = a[12] ^ d2
bc4 = t<<61 | t>>(64-61)
t = a[23] ^ d3
bc0 = t<<28 | t>>(64-28)
t = a[9] ^ d4
bc1 = t<<20 | t>>(64-20)
a[15] = bc0 ^ (bc2 &^ bc1)
a[1] = bc1 ^ (bc3 &^ bc2)
a[12] = bc2 ^ (bc4 &^ bc3)
a[23] = bc3 ^ (bc0 &^ bc4)
a[9] = bc4 ^ (bc1 &^ bc0)
t = a[5] ^ d0
bc4 = t<<18 | t>>(64-18)
t = a[16] ^ d1
bc0 = t<<1 | t>>(64-1)
t = a[2] ^ d2
bc1 = t<<6 | t>>(64-6)
t = a[13] ^ d3
bc2 = t<<25 | t>>(64-25)
t = a[24] ^ d4
bc3 = t<<8 | t>>(64-8)
a[5] = bc0 ^ (bc2 &^ bc1)
a[16] = bc1 ^ (bc3 &^ bc2)
a[2] = bc2 ^ (bc4 &^ bc3)
a[13] = bc3 ^ (bc0 &^ bc4)
a[24] = bc4 ^ (bc1 &^ bc0)
t = a[20] ^ d0
bc1 = t<<36 | t>>(64-36)
t = a[6] ^ d1
bc2 = t<<10 | t>>(64-10)
t = a[17] ^ d2
bc3 = t<<15 | t>>(64-15)
t = a[3] ^ d3
bc4 = t<<56 | t>>(64-56)
t = a[14] ^ d4
bc0 = t<<27 | t>>(64-27)
a[20] = bc0 ^ (bc2 &^ bc1)
a[6] = bc1 ^ (bc3 &^ bc2)
a[17] = bc2 ^ (bc4 &^ bc3)
a[3] = bc3 ^ (bc0 &^ bc4)
a[14] = bc4 ^ (bc1 &^ bc0)
t = a[10] ^ d0
bc3 = t<<41 | t>>(64-41)
t = a[21] ^ d1
bc4 = t<<2 | t>>(64-2)
t = a[7] ^ d2
bc0 = t<<62 | t>>(64-62)
t = a[18] ^ d3
bc1 = t<<55 | t>>(64-55)
t = a[4] ^ d4
bc2 = t<<39 | t>>(64-39)
a[10] = bc0 ^ (bc2 &^ bc1)
a[21] = bc1 ^ (bc3 &^ bc2)
a[7] = bc2 ^ (bc4 &^ bc3)
a[18] = bc3 ^ (bc0 &^ bc4)
a[4] = bc4 ^ (bc1 &^ bc0)
// Round 4
bc0 = a[0] ^ a[5] ^ a[10] ^ a[15] ^ a[20]
bc1 = a[1] ^ a[6] ^ a[11] ^ a[16] ^ a[21]
bc2 = a[2] ^ a[7] ^ a[12] ^ a[17] ^ a[22]
bc3 = a[3] ^ a[8] ^ a[13] ^ a[18] ^ a[23]
bc4 = a[4] ^ a[9] ^ a[14] ^ a[19] ^ a[24]
d0 = bc4 ^ (bc1<<1 | bc1>>63)
d1 = bc0 ^ (bc2<<1 | bc2>>63)
d2 = bc1 ^ (bc3<<1 | bc3>>63)
d3 = bc2 ^ (bc4<<1 | bc4>>63)
d4 = bc3 ^ (bc0<<1 | bc0>>63)
bc0 = a[0] ^ d0
t = a[1] ^ d1
bc1 = t<<44 | t>>(64-44)
t = a[2] ^ d2
bc2 = t<<43 | t>>(64-43)
t = a[3] ^ d3
bc3 = t<<21 | t>>(64-21)
t = a[4] ^ d4
bc4 = t<<14 | t>>(64-14)
a[0] = bc0 ^ (bc2 &^ bc1) ^ rc[i+3]
a[1] = bc1 ^ (bc3 &^ bc2)
a[2] = bc2 ^ (bc4 &^ bc3)
a[3] = bc3 ^ (bc0 &^ bc4)
a[4] = bc4 ^ (bc1 &^ bc0)
t = a[5] ^ d0
bc2 = t<<3 | t>>(64-3)
t = a[6] ^ d1
bc3 = t<<45 | t>>(64-45)
t = a[7] ^ d2
bc4 = t<<61 | t>>(64-61)
t = a[8] ^ d3
bc0 = t<<28 | t>>(64-28)
t = a[9] ^ d4
bc1 = t<<20 | t>>(64-20)
a[5] = bc0 ^ (bc2 &^ bc1)
a[6] = bc1 ^ (bc3 &^ bc2)
a[7] = bc2 ^ (bc4 &^ bc3)
a[8] = bc3 ^ (bc0 &^ bc4)
a[9] = bc4 ^ (bc1 &^ bc0)
t = a[10] ^ d0
bc4 = t<<18 | t>>(64-18)
t = a[11] ^ d1
bc0 = t<<1 | t>>(64-1)
t = a[12] ^ d2
bc1 = t<<6 | t>>(64-6)
t = a[13] ^ d3
bc2 = t<<25 | t>>(64-25)
t = a[14] ^ d4
bc3 = t<<8 | t>>(64-8)
a[10] = bc0 ^ (bc2 &^ bc1)
a[11] = bc1 ^ (bc3 &^ bc2)
a[12] = bc2 ^ (bc4 &^ bc3)
a[13] = bc3 ^ (bc0 &^ bc4)
a[14] = bc4 ^ (bc1 &^ bc0)
t = a[15] ^ d0
bc1 = t<<36 | t>>(64-36)
t = a[16] ^ d1
bc2 = t<<10 | t>>(64-10)
t = a[17] ^ d2
bc3 = t<<15 | t>>(64-15)
t = a[18] ^ d3
bc4 = t<<56 | t>>(64-56)
t = a[19] ^ d4
bc0 = t<<27 | t>>(64-27)
a[15] = bc0 ^ (bc2 &^ bc1)
a[16] = bc1 ^ (bc3 &^ bc2)
a[17] = bc2 ^ (bc4 &^ bc3)
a[18] = bc3 ^ (bc0 &^ bc4)
a[19] = bc4 ^ (bc1 &^ bc0)
t = a[20] ^ d0
bc3 = t<<41 | t>>(64-41)
t = a[21] ^ d1
bc4 = t<<2 | t>>(64-2)
t = a[22] ^ d2
bc0 = t<<62 | t>>(64-62)
t = a[23] ^ d3
bc1 = t<<55 | t>>(64-55)
t = a[24] ^ d4
bc2 = t<<39 | t>>(64-39)
a[20] = bc0 ^ (bc2 &^ bc1)
a[21] = bc1 ^ (bc3 &^ bc2)
a[22] = bc2 ^ (bc4 &^ bc3)
a[23] = bc3 ^ (bc0 &^ bc4)
a[24] = bc4 ^ (bc1 &^ bc0)
}
}

237
crypto/sha3/sha3.go
Unescape View File

@ -1,237 +0,0 @@
// Copyright 2013 The Go Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Package sha3 implements the SHA3 hash algorithm (formerly called Keccak) chosen by NIST in 2012.
// This file provides a SHA3 implementation which implements the standard hash.Hash interface.
// Writing input data, including padding, and reading output data are computed in this file.
// Note that the current implementation can compute the hash of an integral number of bytes only.
// This is a consequence of the hash interface in which a buffer of bytes is passed in.
// The internals of the Keccak-f function are computed in keccakf.go.
// For the detailed specification, refer to the Keccak web site (http://keccak.noekeon.org/).
package sha3
import (
"encoding/binary"
"hash"
)
// laneSize is the size in bytes of each "lane" of the internal state of SHA3 (5 * 5 * 8).
// Note that changing this size would requires using a type other than uint64 to store each lane.
const laneSize = 8
// sliceSize represents the dimensions of the internal state, a square matrix of
// sliceSize ** 2 lanes. This is the size of both the "rows" and "columns" dimensions in the
// terminology of the SHA3 specification.
const sliceSize = 5
// numLanes represents the total number of lanes in the state.
const numLanes = sliceSize * sliceSize
// stateSize is the size in bytes of the internal state of SHA3 (5 * 5 * WSize).
const stateSize = laneSize * numLanes
// digest represents the partial evaluation of a checksum.
// Note that capacity, and not outputSize, is the critical security parameter, as SHA3 can output
// an arbitrary number of bytes for any given capacity. The Keccak proposal recommends that
// capacity = 2*outputSize to ensure that finding a collision of size outputSize requires
// O(2^{outputSize/2}) computations (the birthday lower bound). Future standards may modify the
// capacity/outputSize ratio to allow for more output with lower cryptographic security.
type digest struct {
a [numLanes]uint64 // main state of the hash
outputSize int // desired output size in bytes
capacity int // number of bytes to leave untouched during squeeze/absorb
absorbed int // number of bytes absorbed thus far
}
// minInt returns the lesser of two integer arguments, to simplify the absorption routine.
func minInt(v1, v2 int) int {
if v1 <= v2 {
return v1
}
return v2
}
// rate returns the number of bytes of the internal state which can be absorbed or squeezed
// in between calls to the permutation function.
func (d *digest) rate() int {
return stateSize - d.capacity
}
// Reset clears the internal state by zeroing bytes in the state buffer.
// This can be skipped for a newly-created hash state; the default zero-allocated state is correct.
func (d *digest) Reset() {
d.absorbed = 0
for i := range d.a {
d.a[i] = 0
}
}
// BlockSize, required by the hash.Hash interface, does not have a standard intepretation
// for a sponge-based construction like SHA3. We return the data rate: the number of bytes which
// can be absorbed per invocation of the permutation function. For Merkle-Damgård based hashes
// (ie SHA1, SHA2, MD5) the output size of the internal compression function is returned.
// We consider this to be roughly equivalent because it represents the number of bytes of output
// produced per cryptographic operation.
func (d *digest) BlockSize() int { return d.rate() }
// Size returns the output size of the hash function in bytes.
func (d *digest) Size() int {
return d.outputSize
}
// unalignedAbsorb is a helper function for Write, which absorbs data that isn't aligned with an
// 8-byte lane. This requires shifting the individual bytes into position in a uint64.
func (d *digest) unalignedAbsorb(p []byte) {
var t uint64
for i := len(p) - 1; i >= 0; i-- {
t <<= 8
t |= uint64(p[i])
}
offset := (d.absorbed) % d.rate()
t <<= 8 * uint(offset%laneSize)
d.a[offset/laneSize] ^= t
d.absorbed += len(p)
}
// Write "absorbs" bytes into the state of the SHA3 hash, updating as needed when the sponge
// "fills up" with rate() bytes. Since lanes are stored internally as type uint64, this requires
// converting the incoming bytes into uint64s using a little endian interpretation. This
// implementation is optimized for large, aligned writes of multiples of 8 bytes (laneSize).
// Non-aligned or uneven numbers of bytes require shifting and are slower.
func (d *digest) Write(p []byte) (int, error) {
// An initial offset is needed if the we aren't absorbing to the first lane initially.
offset := d.absorbed % d.rate()
toWrite := len(p)
// The first lane may need to absorb unaligned and/or incomplete data.
if (offset%laneSize != 0 || len(p) < 8) && len(p) > 0 {
toAbsorb := minInt(laneSize-(offset%laneSize), len(p))
d.unalignedAbsorb(p[:toAbsorb])
p = p[toAbsorb:]
offset = (d.absorbed) % d.rate()
// For every rate() bytes absorbed, the state must be permuted via the F Function.
if (d.absorbed)%d.rate() == 0 {
keccakF1600(&d.a)
}
}
// This loop should absorb the bulk of the data into full, aligned lanes.
// It will call the update function as necessary.
for len(p) > 7 {
firstLane := offset / laneSize
lastLane := minInt(d.rate()/laneSize, firstLane+len(p)/laneSize)
// This inner loop absorbs input bytes into the state in groups of 8, converted to uint64s.
for lane := firstLane; lane < lastLane; lane++ {
d.a[lane] ^= binary.LittleEndian.Uint64(p[:laneSize])
p = p[laneSize:]
}
d.absorbed += (lastLane - firstLane) * laneSize
// For every rate() bytes absorbed, the state must be permuted via the F Function.
if (d.absorbed)%d.rate() == 0 {
keccakF1600(&d.a)
}
offset = 0
}
// If there are insufficient bytes to fill the final lane, an unaligned absorption.
// This should always start at a correct lane boundary though, or else it would be caught
// by the uneven opening lane case above.
if len(p) > 0 {
d.unalignedAbsorb(p)
}
return toWrite, nil
}
// pad computes the SHA3 padding scheme based on the number of bytes absorbed.
// The padding is a 1 bit, followed by an arbitrary number of 0s and then a final 1 bit, such that
// the input bits plus padding bits are a multiple of rate(). Adding the padding simply requires
// xoring an opening and closing bit into the appropriate lanes.
func (d *digest) pad() {
offset := d.absorbed % d.rate()
// The opening pad bit must be shifted into position based on the number of bytes absorbed
padOpenLane := offset / laneSize
d.a[padOpenLane] ^= 0x0000000000000001 << uint(8*(offset%laneSize))
// The closing padding bit is always in the last position
padCloseLane := (d.rate() / laneSize) - 1
d.a[padCloseLane] ^= 0x8000000000000000
}
// finalize prepares the hash to output data by padding and one final permutation of the state.
func (d *digest) finalize() {
d.pad()
keccakF1600(&d.a)
}
// squeeze outputs an arbitrary number of bytes from the hash state.
// Squeezing can require multiple calls to the F function (one per rate() bytes squeezed),
// although this is not the case for standard SHA3 parameters. This implementation only supports
// squeezing a single time, subsequent squeezes may lose alignment. Future implementations
// may wish to support multiple squeeze calls, for example to support use as a PRNG.
func (d *digest) squeeze(in []byte, toSqueeze int) []byte {
// Because we read in blocks of laneSize, we need enough room to read
// an integral number of lanes
needed := toSqueeze + (laneSize-toSqueeze%laneSize)%laneSize
if cap(in)-len(in) < needed {
newIn := make([]byte, len(in), len(in)+needed)
copy(newIn, in)
in = newIn
}
out := in[len(in) : len(in)+needed]
for len(out) > 0 {
for i := 0; i < d.rate() && len(out) > 0; i += laneSize {
binary.LittleEndian.PutUint64(out[:], d.a[i/laneSize])
out = out[laneSize:]
}
if len(out) > 0 {
keccakF1600(&d.a)
}
}
return in[:len(in)+toSqueeze] // Re-slice in case we wrote extra data.
}
// Sum applies padding to the hash state and then squeezes out the desired nubmer of output bytes.
func (d *digest) Sum(in []byte) []byte {
// Make a copy of the original hash so that caller can keep writing and summing.
dup := *d
dup.finalize()
return dup.squeeze(in, dup.outputSize)
}
// The NewKeccakX constructors enable initializing a hash in any of the four recommend sizes
// from the Keccak specification, all of which set capacity=2*outputSize. Note that the final
// NIST standard for SHA3 may specify different input/output lengths.
// The output size is indicated in bits but converted into bytes internally.
func NewKeccak224() hash.Hash { return &digest{outputSize: 224 / 8, capacity: 2 * 224 / 8} }
func NewKeccak256() hash.Hash { return &digest{outputSize: 256 / 8, capacity: 2 * 256 / 8} }
func NewKeccak384() hash.Hash { return &digest{outputSize: 384 / 8, capacity: 2 * 384 / 8} }
func NewKeccak512() hash.Hash { return &digest{outputSize: 512 / 8, capacity: 2 * 512 / 8} }
Write Preview
Loading…
Cancel
Save