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 <stdint.h>
34
35 #include "bswap.h"
36 #include "intreadwrite.h"
37 #include "mem.h"
38 #include "md5.h"
39
40 typedef struct AVMD5 {
41 uint64_t len;
42 uint8_t block[64];
43 uint32_t ABCD[4];
44 } AVMD5;
45
46 const int av_md5_size = sizeof(AVMD5);
47
av_md5_alloc(void)48 struct AVMD5 *av_md5_alloc(void)
49 {
50 return av_mallocz(sizeof(struct AVMD5));
51 }
52
53 static const uint8_t S[4][4] = {
54 { 7, 12, 17, 22 }, /* round 1 */
55 { 5, 9, 14, 20 }, /* round 2 */
56 { 4, 11, 16, 23 }, /* round 3 */
57 { 6, 10, 15, 21 } /* round 4 */
58 };
59
60 static const uint32_t T[64] = { // T[i]= fabs(sin(i+1)<<32)
61 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, /* round 1 */
62 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
63 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
64 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
65
66 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, /* round 2 */
67 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
68 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
69 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
70
71 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, /* round 3 */
72 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
73 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
74 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
75
76 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, /* round 4 */
77 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
78 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
79 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391,
80 };
81
82 #define CORE(i, a, b, c, d) \
83 do { \
84 t = S[i >> 4][i & 3]; \
85 a += T[i]; \
86 \
87 if (i < 32) { \
88 if (i < 16) \
89 a += (d ^ (b & (c ^ d))) + AV_RL32(X+( i & 15));\
90 else \
91 a += ((d & b) | (~d & c)) + AV_RL32(X+((1 + 5*i) & 15));\
92 } else { \
93 if (i < 48) \
94 a += (b ^ c ^ d) + AV_RL32(X+((5 + 3*i) & 15));\
95 else \
96 a += (c ^ (b | ~d)) + AV_RL32(X+(( 7*i) & 15));\
97 } \
98 a = b + (a << t | a >> (32 - t)); \
99 } while (0)
100
body(uint32_t ABCD[4],const uint8_t * src,size_t nblocks)101 static void body(uint32_t ABCD[4], const uint8_t *src, size_t nblocks)
102 {
103 const uint32_t *X;
104 uint32_t a, b, c, d, t;
105
106 for (size_t n = 0; n < nblocks; n++) {
107 a = ABCD[3];
108 b = ABCD[2];
109 c = ABCD[1];
110 d = ABCD[0];
111
112 X = (const uint32_t *)src + n * 16;
113
114 #if CONFIG_SMALL
115 for (int i = 0; i < 64; i++) {
116 CORE(i, a, b, c, d);
117 t = d;
118 d = c;
119 c = b;
120 b = a;
121 a = t;
122 }
123 #else
124 #define CORE2(i) \
125 CORE(i, a, b, c, d); CORE((i + 1), d, a, b, c); \
126 CORE((i + 2), c, d, a, b); CORE((i + 3), b, c, d, a)
127 #define CORE4(i) CORE2(i); CORE2((i + 4)); CORE2((i + 8)); CORE2((i + 12))
128 CORE4(0);
129 CORE4(16);
130 CORE4(32);
131 CORE4(48);
132 #endif
133
134 ABCD[0] += d;
135 ABCD[1] += c;
136 ABCD[2] += b;
137 ABCD[3] += a;
138 }
139 }
140
av_md5_init(AVMD5 * ctx)141 void av_md5_init(AVMD5 *ctx)
142 {
143 ctx->len = 0;
144
145 ctx->ABCD[0] = 0x10325476;
146 ctx->ABCD[1] = 0x98badcfe;
147 ctx->ABCD[2] = 0xefcdab89;
148 ctx->ABCD[3] = 0x67452301;
149 }
150
av_md5_update(AVMD5 * ctx,const uint8_t * src,size_t len)151 void av_md5_update(AVMD5 *ctx, const uint8_t *src, size_t len)
152 {
153 const uint8_t *end;
154 int j;
155
156 j = ctx->len & 63;
157 ctx->len += len;
158
159 if (j) {
160 int cnt = FFMIN(len, 64 - j);
161 memcpy(ctx->block + j, src, cnt);
162 src += cnt;
163 len -= cnt;
164 if (j + cnt < 64)
165 return;
166 body(ctx->ABCD, ctx->block, 1);
167 }
168
169 end = src + (len & ~63);
170 if (!HAVE_FAST_UNALIGNED && ((intptr_t)src & 3)) {
171 while (src < end) {
172 memcpy(ctx->block, src, 64);
173 body(ctx->ABCD, ctx->block, 1);
174 src += 64;
175 }
176 } else {
177 size_t nblocks = len / 64;
178 body(ctx->ABCD, src, nblocks);
179 src = end;
180 }
181 len &= 63;
182 if (len > 0)
183 memcpy(ctx->block, src, len);
184 }
185
av_md5_final(AVMD5 * ctx,uint8_t * dst)186 void av_md5_final(AVMD5 *ctx, uint8_t *dst)
187 {
188 int i;
189 uint64_t finalcount = av_le2ne64(ctx->len << 3);
190
191 av_md5_update(ctx, "\200", 1);
192 while ((ctx->len & 63) != 56)
193 av_md5_update(ctx, "", 1);
194
195 av_md5_update(ctx, (uint8_t *) &finalcount, 8);
196
197 for (i = 0; i < 4; i++)
198 AV_WL32(dst + 4 * i, ctx->ABCD[3 - i]);
199 }
200
av_md5_sum(uint8_t * dst,const uint8_t * src,size_t len)201 void av_md5_sum(uint8_t *dst, const uint8_t *src, size_t len)
202 {
203 AVMD5 ctx;
204
205 av_md5_init(&ctx);
206 av_md5_update(&ctx, src, len);
207 av_md5_final(&ctx, dst);
208 }
209