src/SHA256.cpp
Rama master · réplica de lectura del repositorio original.
/*
* FIPS 180-2 SHA-224/256/384/512 implementation
* Last update: 02/02/2007
* Issue date: 04/30/2005
*
* Copyright (C) 2005, 2007 Olivier Gay <olivier.gay@a3.epfl.ch>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the project 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 PROJECT 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 PROJECT 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.
*/
#include <znc/SHA256.h>
#include <string.h>
#define SHFR(x, n) (x >> n)
#define ROTR(x, n) ((x >> n) | (x << ((sizeof(x) << 3) - n)))
#define ROTL(x, n) ((x << n) | (x >> ((sizeof(x) << 3) - n)))
#define CH(x, y, z) ((x & y) ^ (~x & z))
#define MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define SHA256_F1(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
#define SHA256_F2(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
#define SHA256_F3(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHFR(x, 3))
#define SHA256_F4(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHFR(x, 10))
#define UNPACK32(x, str) \
{ \
*((str)+3) = (uint8_t)((x)); \
*((str)+2) = (uint8_t)((x) >> 8); \
*((str)+1) = (uint8_t)((x) >> 16); \
*((str)+0) = (uint8_t)((x) >> 24); \
}
#define PACK32(str, x) \
{ \
*(x) = ((uint32_t) * ((str)+3)) | ((uint32_t) * ((str)+2) << 8) | \
((uint32_t) * ((str)+1) << 16) | \
((uint32_t) * ((str)+0) << 24); \
}
/* Macros used for loops unrolling */
#define SHA256_SCR(i) \
{ \
w[i] = \
SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16]; \
}
#define SHA256_EXP(a, b, c, d, e, f, g, h, j) \
{ \
t1 = wv[h] + SHA256_F2(wv[e]) + CH(wv[e], wv[f], wv[g]) + \
sha256_k[j] + w[j]; \
t2 = SHA256_F1(wv[a]) + MAJ(wv[a], wv[b], wv[c]); \
wv[d] += t1; \
wv[h] = t1 + t2; \
}
uint32_t sha256_h0[8] = {0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19};
uint32_t sha256_k[64] = {
0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};
/* SHA-256 functions */
static void sha256_transf(sha256_ctx* ctx, const unsigned char* message,
size_t block_nb) {
uint32_t w[64];
uint32_t wv[8];
uint32_t t1, t2;
const unsigned char* sub_block;
int i;
int j;
for (i = 0; i < (int)block_nb; i++) {
sub_block = message + (i << 6);
for (j = 0; j < 16; j++) {
PACK32(&sub_block[j << 2], &w[j]);
}
for (j = 16; j < 64; j++) {
SHA256_SCR(j);
}
for (j = 0; j < 8; j++) {
wv[j] = ctx->h[j];
}
for (j = 0; j < 64; j++) {
t1 = wv[7] + SHA256_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) +
sha256_k[j] + w[j];
t2 = SHA256_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]);
wv[7] = wv[6];
wv[6] = wv[5];
wv[5] = wv[4];
wv[4] = wv[3] + t1;
wv[3] = wv[2];
wv[2] = wv[1];
wv[1] = wv[0];
wv[0] = t1 + t2;
}
for (j = 0; j < 8; j++) {
ctx->h[j] += wv[j];
}
}
}
void sha256(const unsigned char* message, size_t len, unsigned char* digest) {
sha256_ctx ctx;
sha256_init(&ctx);
sha256_update(&ctx, message, len);
sha256_final(&ctx, digest);
}
void sha256_init(sha256_ctx* ctx) {
int i;
for (i = 0; i < 8; i++) {
ctx->h[i] = sha256_h0[i];
}
ctx->len = 0;
ctx->tot_len = 0;
}
void sha256_update(sha256_ctx* ctx, const unsigned char* message, size_t len) {
size_t block_nb;
size_t new_len, rem_len, tmp_len;
const unsigned char* shifted_message;
tmp_len = SHA256_BLOCK_SIZE - ctx->len;
rem_len = len < tmp_len ? len : tmp_len;
memcpy(&ctx->block[ctx->len], message, rem_len);
if (ctx->len + len < SHA256_BLOCK_SIZE) {
ctx->len += len;
return;
}
new_len = len - rem_len;
block_nb = new_len / SHA256_BLOCK_SIZE;
shifted_message = message + rem_len;
sha256_transf(ctx, ctx->block, 1);
sha256_transf(ctx, shifted_message, block_nb);
rem_len = new_len % SHA256_BLOCK_SIZE;
memcpy(ctx->block, &shifted_message[block_nb << 6], rem_len);
ctx->len = rem_len;
ctx->tot_len += (block_nb + 1) << 6;
}
void sha256_final(sha256_ctx* ctx, unsigned char* digest) {
unsigned int block_nb;
unsigned int pm_len;
size_t len_b;
int i;
block_nb = (1 + ((SHA256_BLOCK_SIZE - 9) < (ctx->len % SHA256_BLOCK_SIZE)));
len_b = (ctx->tot_len + ctx->len) << 3;
pm_len = block_nb << 6;
memset(ctx->block + ctx->len, 0, pm_len - ctx->len);
ctx->block[ctx->len] = 0x80;
UNPACK32(len_b, ctx->block + pm_len - 4);
sha256_transf(ctx, ctx->block, block_nb);
for (i = 0; i < 8; i++) {
UNPACK32(ctx->h[i], &digest[i << 2]);
}
}