libavutil/md5.c

   1 /*
   2  * Copyright (C) 2006 Michael Niedermayer (michaelni@gmx.at)
   3  * Copyright (C) 2003-2005 by Christopher R. Hertel (crh@ubiqx.mn.org)
   4  *
   5  * References:
   6  *  IETF RFC 1321: The MD5 Message-Digest Algorithm
   7  *       Ron Rivest. IETF, April, 1992
   8  *
   9  * based on http://ubiqx.org/libcifs/source/Auth/MD5.c
  10  *          from Christopher R. Hertel (crh@ubiqx.mn.org)
  11  * Simplified, cleaned and IMO redundant comments removed by michael.
  12  *
  13  * If you use gcc, then version 4.1 or later and -fomit-frame-pointer is
  14  * strongly recommended.
  15  *
  16  * This file is part of FFmpeg.
  17  *
  18  * FFmpeg is free software; you can redistribute it and/or
  19  * modify it under the terms of the GNU Lesser General Public
  20  * License as published by the Free Software Foundation; either
  21  * version 2.1 of the License, or (at your option) any later version.
  22  *
  23  * FFmpeg is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  26  * Lesser General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU Lesser General Public
  29  * License along with FFmpeg; if not, write to the Free Software
  30  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  31  */
  32
  33 #include <string.h>
  34 #include "bswap.h"
  35 #include "md5.h"
  36
  37 typedef struct AVMD5{
  38     uint64_t len;
  39     uint8_t  block[64];
  40     uint32_t ABCD[4];
  41 } AVMD5;
  42
  43 const int av_md5_size= sizeof(AVMD5);
  44
  45 static const uint8_t S[4][4] = {
  46     { 7, 12, 17, 22 },  /* round 1 */
  47     { 5,  9, 14, 20 },  /* round 2 */
  48     { 4, 11, 16, 23 },  /* round 3 */
  49     { 6, 10, 15, 21 }   /* round 4 */
  50 };
  51
  52 static const uint32_t T[64] = { // T[i]= fabs(sin(i+1)<<32)
  53     0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,   /* round 1 */
  54     0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
  55     0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
  56     0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
  57
  58     0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,   /* round 2 */
  59     0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
  60     0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
  61     0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
  62
  63     0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,   /* round 3 */
  64     0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
  65     0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
  66     0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
  67
  68     0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,   /* round 4 */
  69     0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
  70     0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
  71     0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391,
  72 };
  73
  74 #define CORE(i, a, b, c, d) \
  75         t = S[i>>4][i&3];\
  76         a += T[i];\
  77 \
  78         if(i<32){\
  79             if(i<16) a += (d ^ (b&(c^d))) + X[      i &15 ];\
  80             else     a += (c ^ (d&(c^b))) + X[ (1+5*i)&15 ];\
  81         }else{\
  82             if(i<48) a += (b^c^d)         + X[ (5+3*i)&15 ];\
  83             else     a += (c^(b|~d))      + X[ (  7*i)&15 ];\
  84         }\
  85         a = b + (( a << t ) | ( a >> (32 - t) ));
  86
  87 static void body(uint32_t ABCD[4], uint32_t X[16]){
  88
  89     int t;
  90     int i av_unused;
  91     unsigned int a= ABCD[3];
  92     unsigned int b= ABCD[2];
  93     unsigned int c= ABCD[1];
  94     unsigned int d= ABCD[0];
  95
  96 #if HAVE_BIGENDIAN
  97     for(i=0; i<16; i++)
  98         X[i]= bswap_32(X[i]);
  99 #endif
 100
 101 #if CONFIG_SMALL
 102     for( i = 0; i < 64; i++ ){
 103         CORE(i,a,b,c,d)
 104         t=d; d=c; c=b; b=a; a=t;
 105     }
 106 #else
 107 #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)
 108 #define CORE4(i) CORE2(i) CORE2((i+4)) CORE2((i+8)) CORE2((i+12))
 109 CORE4(0) CORE4(16) CORE4(32) CORE4(48)
 110 #endif
 111
 112     ABCD[0] += d;
 113     ABCD[1] += c;
 114     ABCD[2] += b;
 115     ABCD[3] += a;
 116 }
 117
 118 void av_md5_init(AVMD5 *ctx){
 119     ctx->len    = 0;
 120
 121     ctx->ABCD[0] = 0x10325476;
 122     ctx->ABCD[1] = 0x98badcfe;
 123     ctx->ABCD[2] = 0xefcdab89;
 124     ctx->ABCD[3] = 0x67452301;
 125 }
 126
 127 void av_md5_update(AVMD5 *ctx, const uint8_t *src, const int len){
 128     int i, j;
 129
 130     j= ctx->len & 63;
 131     ctx->len += len;
 132
 133     for( i = 0; i < len; i++ ){
 134         ctx->block[j++] = src[i];
 135         if( 64 == j ){
 136             body(ctx->ABCD, (uint32_t*) ctx->block);
 137             j = 0;
 138         }
 139     }
 140 }
 141
 142 void av_md5_final(AVMD5 *ctx, uint8_t *dst){
 143     int i;
 144     uint64_t finalcount= le2me_64(ctx->len<<3);
 145
 146     av_md5_update(ctx, "\200", 1);
 147     while((ctx->len & 63)!=56)
 148         av_md5_update(ctx, "", 1);
 149
 150     av_md5_update(ctx, (uint8_t*)&finalcount, 8);
 151
 152     for(i=0; i<4; i++)
 153         ((uint32_t*)dst)[i]= le2me_32(ctx->ABCD[3-i]);
 154 }
 155
 156 void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len){
 157     AVMD5 ctx[1];
 158
 159     av_md5_init(ctx);
 160     av_md5_update(ctx, src, len);
 161     av_md5_final(ctx, dst);
 162 }
 163
 164 #ifdef TEST
 165 #include <stdio.h>
 166 #undef printf
 167 int main(void){
 168     uint64_t md5val;
 169     int i;
 170     uint8_t in[1000];
 171
 172     for(i=0; i<1000; i++) in[i]= i*i;
 173     av_md5_sum( (uint8_t*)&md5val, in,  1000); printf("%"PRId64"\n", md5val);
 174     av_md5_sum( (uint8_t*)&md5val, in,  63); printf("%"PRId64"\n", md5val);
 175     av_md5_sum( (uint8_t*)&md5val, in,  64); printf("%"PRId64"\n", md5val);
 176     av_md5_sum( (uint8_t*)&md5val, in,  65); printf("%"PRId64"\n", md5val);
 177     for(i=0; i<1000; i++) in[i]= i % 127;
 178     av_md5_sum( (uint8_t*)&md5val, in,  999); printf("%"PRId64"\n", md5val);
 179
 180     return 0;
 181 }
 182 #endif