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
37typedef struct AVMD5{
38    uint64_t len;
39    uint8_t  block[64];
40    uint32_t ABCD[4];
41} AVMD5;
42
43const int av_md5_size= sizeof(AVMD5);
44
45static 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
52static 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
87static 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))
109CORE4(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
118void 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
127void 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
142void 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
156void 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#include <inttypes.h>
167#undef printf
168int main(void){
169    uint64_t md5val;
170    int i;
171    uint8_t in[1000];
172
173    for(i=0; i<1000; i++) in[i]= i*i;
174    av_md5_sum( (uint8_t*)&md5val, in,  1000); printf("%"PRId64"\n", md5val);
175    av_md5_sum( (uint8_t*)&md5val, in,  63); printf("%"PRId64"\n", md5val);
176    av_md5_sum( (uint8_t*)&md5val, in,  64); printf("%"PRId64"\n", md5val);
177    av_md5_sum( (uint8_t*)&md5val, in,  65); printf("%"PRId64"\n", md5val);
178    for(i=0; i<1000; i++) in[i]= i % 127;
179    av_md5_sum( (uint8_t*)&md5val, in,  999); printf("%"PRId64"\n", md5val);
180
181    return 0;
182}
183#endif
184