FFmpeg/libavutil/md5.c
James Almer a876958d0f avutil/md5: fix misaligned reads
This makes ubsan happy and also considerably increases performance on
big endian systems.

Tested on an IBM POWER7 3.55 GHz

Before:

2.24user 0.14system 0:02.39elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
2.26user 0.11system 0:02.38elapsed 99%CPU (0avgtext+0avgdata 2688maxresident)k
2.23user 0.15system 0:02.38elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
2.25user 0.12system 0:02.38elapsed 100%CPU (0avgtext+0avgdata 2624maxresident)k
2.20user 0.15system 0:02.36elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k

After:

1.86user 0.13system 0:02.00elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
1.89user 0.11system 0:02.01elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
1.85user 0.14system 0:02.00elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
1.84user 0.15system 0:01.99elapsed 99%CPU (0avgtext+0avgdata 2624maxresident)k
1.89user 0.13system 0:02.02elapsed 99%CPU (0avgtext+0avgdata 2688maxresident)k

Tested-by: Nicolas George <george@nsup.org>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Sean McGovern <gseanmcg@gmail.com>
2017-06-02 21:00:35 -04:00

219 lines
6.6 KiB
C

/*
* Copyright (C) 2006 Michael Niedermayer (michaelni@gmx.at)
* Copyright (C) 2003-2005 by Christopher R. Hertel (crh@ubiqx.mn.org)
*
* References:
* IETF RFC 1321: The MD5 Message-Digest Algorithm
* Ron Rivest. IETF, April, 1992
*
* based on http://ubiqx.org/libcifs/source/Auth/MD5.c
* from Christopher R. Hertel (crh@ubiqx.mn.org)
* Simplified, cleaned and IMO redundant comments removed by Michael.
*
* If you use gcc, then version 4.1 or later and -fomit-frame-pointer is
* strongly recommended.
*
* 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 <stdint.h>
#include "bswap.h"
#include "intreadwrite.h"
#include "mem.h"
#include "md5.h"
typedef struct AVMD5 {
uint64_t len;
uint8_t block[64];
uint32_t ABCD[4];
} AVMD5;
const int av_md5_size = sizeof(AVMD5);
struct AVMD5 *av_md5_alloc(void)
{
return av_mallocz(sizeof(struct AVMD5));
}
static const uint8_t S[4][4] = {
{ 7, 12, 17, 22 }, /* round 1 */
{ 5, 9, 14, 20 }, /* round 2 */
{ 4, 11, 16, 23 }, /* round 3 */
{ 6, 10, 15, 21 } /* round 4 */
};
static const uint32_t T[64] = { // T[i]= fabs(sin(i+1)<<32)
0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, /* round 1 */
0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, /* round 2 */
0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, /* round 3 */
0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, /* round 4 */
0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391,
};
#define CORE(i, a, b, c, d) \
do { \
t = S[i >> 4][i & 3]; \
a += T[i]; \
\
if (i < 32) { \
if (i < 16) \
a += (d ^ (b & (c ^ d))) + AV_RL32(X+( i & 15));\
else \
a += ((d & b) | (~d & c)) + AV_RL32(X+((1 + 5*i) & 15));\
} else { \
if (i < 48) \
a += (b ^ c ^ d) + AV_RL32(X+((5 + 3*i) & 15));\
else \
a += (c ^ (b | ~d)) + AV_RL32(X+(( 7*i) & 15));\
} \
a = b + (a << t | a >> (32 - t)); \
} while (0)
static void body(uint32_t ABCD[4], const uint8_t *src, int nblocks)
{
int i av_unused;
int n;
const uint32_t *X;
uint32_t a, b, c, d, t;
for (n = 0; n < nblocks; n++) {
a = ABCD[3];
b = ABCD[2];
c = ABCD[1];
d = ABCD[0];
X = (const uint32_t *)src + n * 16;
#if CONFIG_SMALL
for (i = 0; i < 64; i++) {
CORE(i, a, b, c, d);
t = d;
d = c;
c = b;
b = a;
a = t;
}
#else
#define CORE2(i) \
CORE(i, a, b, c, d); CORE((i + 1), d, a, b, c); \
CORE((i + 2), c, d, a, b); CORE((i + 3), b, c, d, a)
#define CORE4(i) CORE2(i); CORE2((i + 4)); CORE2((i + 8)); CORE2((i + 12))
CORE4(0);
CORE4(16);
CORE4(32);
CORE4(48);
#endif
ABCD[0] += d;
ABCD[1] += c;
ABCD[2] += b;
ABCD[3] += a;
}
}
void av_md5_init(AVMD5 *ctx)
{
ctx->len = 0;
ctx->ABCD[0] = 0x10325476;
ctx->ABCD[1] = 0x98badcfe;
ctx->ABCD[2] = 0xefcdab89;
ctx->ABCD[3] = 0x67452301;
}
#if FF_API_CRYPTO_SIZE_T
void av_md5_update(AVMD5 *ctx, const uint8_t *src, int len)
#else
void av_md5_update(AVMD5 *ctx, const uint8_t *src, size_t len)
#endif
{
const uint8_t *end;
int j;
j = ctx->len & 63;
ctx->len += len;
if (j) {
int cnt = FFMIN(len, 64 - j);
memcpy(ctx->block + j, src, cnt);
src += cnt;
len -= cnt;
if (j + cnt < 64)
return;
body(ctx->ABCD, ctx->block, 1);
}
end = src + (len & ~63);
if (!HAVE_FAST_UNALIGNED && ((intptr_t)src & 3)) {
while (src < end) {
memcpy(ctx->block, src, 64);
body(ctx->ABCD, ctx->block, 1);
src += 64;
}
} else {
int nblocks = len / 64;
body(ctx->ABCD, src, nblocks);
src = end;
}
len &= 63;
if (len > 0)
memcpy(ctx->block, src, len);
}
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
{
int i;
uint64_t finalcount = av_le2ne64(ctx->len << 3);
av_md5_update(ctx, "\200", 1);
while ((ctx->len & 63) != 56)
av_md5_update(ctx, "", 1);
av_md5_update(ctx, (uint8_t *) &finalcount, 8);
for (i = 0; i < 4; i++)
AV_WL32(dst + 4 * i, ctx->ABCD[3 - i]);
}
#if FF_API_CRYPTO_SIZE_T
void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
#else
void av_md5_sum(uint8_t *dst, const uint8_t *src, size_t len)
#endif
{
AVMD5 ctx;
av_md5_init(&ctx);
av_md5_update(&ctx, src, len);
av_md5_final(&ctx, dst);
}