ffmpeg/libavutil/sha1.c

213 lines
6.3 KiB
C

/*
* Copyright (C) 2007 Michael Niedermayer <michaelni@gmx.at>
* based on public domain SHA-1 code by Steve Reid <steve@edmweb.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "common.h"
#include "bswap.h"
#include "sha1.h"
/** hash context */
typedef struct AVSHA1 {
uint8_t digest_len; ///< digest length in 32-bit words
uint64_t count; ///< number of bytes in buffer
uint8_t buffer[64]; ///< 512-bit buffer of input values used in hash updating
uint32_t state[8]; ///< current hash value
/** function used to update hash for 512-bit input block */
void (*transform)(uint32_t *state, const uint8_t buffer[64]);
} AVSHA1;
const int av_sha1_size = sizeof(AVSHA1);
#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#define blk0(i) (block[i] = be2me_32(((const uint32_t*)buffer)[i]))
#define blk(i) (block[i] = rol(block[i-3] ^ block[i-8] ^ block[i-14] ^ block[i-16], 1))
#define R0(v,w,x,y,z,i) z += ((w&(x^y))^y) + blk0(i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
#define R1(v,w,x,y,z,i) z += ((w&(x^y))^y) + blk (i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
#define R2(v,w,x,y,z,i) z += ( w^x ^y) + blk (i) + 0x6ED9EBA1 + rol(v, 5); w = rol(w, 30);
#define R3(v,w,x,y,z,i) z += (((w|x)&y)|(w&x)) + blk (i) + 0x8F1BBCDC + rol(v, 5); w = rol(w, 30);
#define R4(v,w,x,y,z,i) z += ( w^x ^y) + blk (i) + 0xCA62C1D6 + rol(v, 5); w = rol(w, 30);
/* Hash a single 512-bit block. This is the core of the algorithm. */
static void sha1_transform(uint32_t state[5], const uint8_t buffer[64])
{
uint32_t block[80];
unsigned int i, a, b, c, d, e;
a = state[0];
b = state[1];
c = state[2];
d = state[3];
e = state[4];
#if CONFIG_SMALL
for (i = 0; i < 80; i++) {
int t;
if (i < 16)
t = be2me_32(((uint32_t*)buffer)[i]);
else
t = rol(block[i-3] ^ block[i-8] ^ block[i-14] ^ block[i-16], 1);
block[i] = t;
t += e + rol(a, 5);
if (i < 40) {
if (i < 20)
t += ((b&(c^d))^d) + 0x5A827999;
else
t += ( b^c ^d) + 0x6ED9EBA1;
} else {
if (i < 60)
t += (((b|c)&d)|(b&c)) + 0x8F1BBCDC;
else
t += ( b^c ^d) + 0xCA62C1D6;
}
e = d;
d = c;
c = rol(b, 30);
b = a;
a = t;
}
#else
for (i = 0; i < 15; i += 5) {
R0(a, b, c, d, e, 0 + i);
R0(e, a, b, c, d, 1 + i);
R0(d, e, a, b, c, 2 + i);
R0(c, d, e, a, b, 3 + i);
R0(b, c, d, e, a, 4 + i);
}
R0(a, b, c, d, e, 15);
R1(e, a, b, c, d, 16);
R1(d, e, a, b, c, 17);
R1(c, d, e, a, b, 18);
R1(b, c, d, e, a, 19);
for (i = 20; i < 40; i += 5) {
R2(a, b, c, d, e, 0 + i);
R2(e, a, b, c, d, 1 + i);
R2(d, e, a, b, c, 2 + i);
R2(c, d, e, a, b, 3 + i);
R2(b, c, d, e, a, 4 + i);
}
for (; i < 60; i += 5) {
R3(a, b, c, d, e, 0 + i);
R3(e, a, b, c, d, 1 + i);
R3(d, e, a, b, c, 2 + i);
R3(c, d, e, a, b, 3 + i);
R3(b, c, d, e, a, 4 + i);
}
for (; i < 80; i += 5) {
R4(a, b, c, d, e, 0 + i);
R4(e, a, b, c, d, 1 + i);
R4(d, e, a, b, c, 2 + i);
R4(c, d, e, a, b, 3 + i);
R4(b, c, d, e, a, 4 + i);
}
#endif
state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;
state[4] += e;
}
void av_sha1_init(AVSHA1* ctx)
{
ctx->state[0] = 0x67452301;
ctx->state[1] = 0xEFCDAB89;
ctx->state[2] = 0x98BADCFE;
ctx->state[3] = 0x10325476;
ctx->state[4] = 0xC3D2E1F0;
ctx->transform = sha1_transform;
ctx->count = 0;
}
void av_sha1_update(AVSHA1* ctx, const uint8_t* data, unsigned int len)
{
unsigned int i, j;
j = ctx->count & 63;
ctx->count += len;
#if CONFIG_SMALL
for (i = 0; i < len; i++) {
ctx->buffer[j++] = data[i];
if (64 == j) {
ctx->transform(ctx->state, ctx->buffer);
j = 0;
}
}
#else
if ((j + len) > 63) {
memcpy(&ctx->buffer[j], data, (i = 64 - j));
ctx->transform(ctx->state, ctx->buffer);
for (; i + 63 < len; i += 64)
ctx->transform(ctx->state, &data[i]);
j = 0;
} else
i = 0;
memcpy(&ctx->buffer[j], &data[i], len - i);
#endif
}
void av_sha1_final(AVSHA1* ctx, uint8_t digest[20])
{
int i;
uint64_t finalcount = be2me_64(ctx->count << 3);
av_sha1_update(ctx, "\200", 1);
while ((ctx->count & 63) != 56)
av_sha1_update(ctx, "", 1);
av_sha1_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
for (i = 0; i < 5; i++)
((uint32_t*)digest)[i] = be2me_32(ctx->state[i]);
}
#ifdef TEST
#include <stdio.h>
#undef printf
int main(void)
{
int i, k;
AVSHA1 ctx;
unsigned char digest[20];
for (k = 0; k < 3; k++) {
av_sha1_init(&ctx);
if (k == 0)
av_sha1_update(&ctx, "abc", 3);
else if (k == 1)
av_sha1_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
else
for (i = 0; i < 1000 * 1000; i++)
av_sha1_update(&ctx, "a", 1);
av_sha1_final(&ctx, digest);
for (i = 0; i < 20; i++)
printf("%02X", digest[i]);
putchar('\n');
}
//test vectors (from FIPS PUB 180-1)
printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
"84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
"34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
return 0;
}
#endif