Libav
md5.c
Go to the documentation of this file.
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 Libav.
17  *
18  * Libav 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  * Libav 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 Libav; 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;
43  uint32_t ABCD[4];
44 } AVMD5;
45 
46 struct AVMD5 *av_md5_alloc(void)
47 {
48  return av_mallocz(sizeof(struct AVMD5));
49 }
50 
51 static const uint8_t S[4][4] = {
52  { 7, 12, 17, 22 }, /* round 1 */
53  { 5, 9, 14, 20 }, /* round 2 */
54  { 4, 11, 16, 23 }, /* round 3 */
55  { 6, 10, 15, 21 } /* round 4 */
56 };
57 
58 static const uint32_t T[64] = { // T[i]= fabs(sin(i+1)<<32)
59  0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, /* round 1 */
60  0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
61  0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
62  0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
63 
64  0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, /* round 2 */
65  0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
66  0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
67  0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
68 
69  0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, /* round 3 */
70  0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
71  0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
72  0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
73 
74  0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, /* round 4 */
75  0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
76  0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
77  0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391,
78 };
79 
80 #define CORE(i, a, b, c, d) \
81  do { \
82  t = S[i >> 4][i & 3]; \
83  a += T[i]; \
84  \
85  if (i < 32) { \
86  if (i < 16) \
87  a += (d ^ (b & (c ^ d))) + X[i & 15]; \
88  else \
89  a += (c ^ (d & (c ^ b))) + X[(1 + 5 * i) & 15]; \
90  } else { \
91  if (i < 48) \
92  a += (b ^ c ^ d) + X[(5 + 3 * i) & 15]; \
93  else \
94  a += (c ^ (b | ~d)) + X[(7 * i) & 15]; \
95  } \
96  a = b + (a << t | a >> (32 - t)); \
97  } while (0)
98 
99 static void body(uint32_t ABCD[4], uint32_t X[16])
100 {
101  int t;
102  int i av_unused;
103  unsigned int a = ABCD[3];
104  unsigned int b = ABCD[2];
105  unsigned int c = ABCD[1];
106  unsigned int d = ABCD[0];
107 
108 #if HAVE_BIGENDIAN
109  for (i = 0; i < 16; i++)
110  X[i] = av_bswap32(X[i]);
111 #endif
112 
113 #if CONFIG_SMALL
114  for (i = 0; i < 64; i++) {
115  CORE(i, a, b, c, d);
116  t = d;
117  d = c;
118  c = b;
119  b = a;
120  a = t;
121  }
122 #else
123 #define CORE2(i) \
124  CORE(i, a, b, c, d); CORE((i + 1), d, a, b, c); \
125  CORE((i + 2), c, d, a, b); CORE((i + 3), b, c, d, a)
126 #define CORE4(i) CORE2(i); CORE2((i + 4)); CORE2((i + 8)); CORE2((i + 12))
127  CORE4(0);
128  CORE4(16);
129  CORE4(32);
130  CORE4(48);
131 #endif
132 
133  ABCD[0] += d;
134  ABCD[1] += c;
135  ABCD[2] += b;
136  ABCD[3] += a;
137 }
138 
140 {
141  ctx->len = 0;
142 
143  ctx->ABCD[0] = 0x10325476;
144  ctx->ABCD[1] = 0x98badcfe;
145  ctx->ABCD[2] = 0xefcdab89;
146  ctx->ABCD[3] = 0x67452301;
147 }
148 
149 void av_md5_update(AVMD5 *ctx, const uint8_t *src, const int len)
150 {
151  int i, j;
152 
153  j = ctx->len & 63;
154  ctx->len += len;
155 
156  for (i = 0; i < len; i++) {
157  ctx->block[j++] = src[i];
158  if (j == 64) {
159  body(ctx->ABCD, (uint32_t *) ctx->block);
160  j = 0;
161  }
162  }
163 }
164 
166 {
167  int i;
168  uint64_t finalcount = av_le2ne64(ctx->len << 3);
169 
170  av_md5_update(ctx, "\200", 1);
171  while ((ctx->len & 63) != 56)
172  av_md5_update(ctx, "", 1);
173 
174  av_md5_update(ctx, (uint8_t *) &finalcount, 8);
175 
176  for (i = 0; i < 4; i++)
177  AV_WL32(dst + 4 * i, ctx->ABCD[3 - i]);
178 }
179 
180 void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
181 {
182  AVMD5 ctx;
183 
184  av_md5_init(&ctx);
185  av_md5_update(&ctx, src, len);
186  av_md5_final(&ctx, dst);
187 }
static const uint32_t T[64]
Definition: md5.c:58
static const uint8_t S[4][4]
Definition: md5.c:51
memory handling functions
static void body(uint32_t ABCD[4], uint32_t X[16])
Definition: md5.c:99
struct AVMD5 * av_md5_alloc(void)
Definition: md5.c:46
uint8_t
#define b
Definition: input.c:52
void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
Definition: md5.c:180
Definition: md5.c:40
#define src
Definition: vp8dsp.c:254
void av_md5_update(AVMD5 *ctx, const uint8_t *src, const int len)
Definition: md5.c:149
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t block[64]
Definition: md5.c:42
#define CORE4(i)
#define av_bswap32
Definition: bswap.h:33
void av_md5_init(AVMD5 *ctx)
Definition: md5.c:139
uint64_t len
Definition: md5.c:41
#define av_le2ne64(x)
Definition: bswap.h:99
byte swapping routines
#define CORE(i, a, b, c, d)
Definition: md5.c:80
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
Definition: md5.c:165
uint32_t ABCD[4]
Definition: md5.c:43
#define AV_WL32(p, val)
Definition: intreadwrite.h:263
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:211
#define av_unused
Definition: attributes.h:86