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md5.c
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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;
43  uint32_t ABCD[4];
44 } AVMD5;
45 
46 const int av_md5_size = sizeof(AVMD5);
47 
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))) + X[ i & 15]; \
90  else \
91  a += ((d & b) | (~d & c)) + X[(1 + 5*i) & 15]; \
92  } else { \
93  if (i < 48) \
94  a += (b ^ c ^ d) + X[(5 + 3*i) & 15]; \
95  else \
96  a += (c ^ (b | ~d)) + X[( 7*i) & 15]; \
97  } \
98  a = b + (a << t | a >> (32 - t)); \
99  } while (0)
100 
101 static void body(uint32_t ABCD[4], uint32_t *src, int nblocks)
102 {
103  int i av_unused;
104  int n;
105  uint32_t a, b, c, d, t, *X;
106 
107  for (n = 0; n < nblocks; n++) {
108  a = ABCD[3];
109  b = ABCD[2];
110  c = ABCD[1];
111  d = ABCD[0];
112 
113  X = src + n * 16;
114 
115 #if HAVE_BIGENDIAN
116  for (i = 0; i < 16; i++)
117  X[i] = av_bswap32(X[i]);
118 #endif
119 
120 #if CONFIG_SMALL
121  for (i = 0; i < 64; i++) {
122  CORE(i, a, b, c, d);
123  t = d;
124  d = c;
125  c = b;
126  b = a;
127  a = t;
128  }
129 #else
130 #define CORE2(i) \
131  CORE(i, a, b, c, d); CORE((i + 1), d, a, b, c); \
132  CORE((i + 2), c, d, a, b); CORE((i + 3), b, c, d, a)
133 #define CORE4(i) CORE2(i); CORE2((i + 4)); CORE2((i + 8)); CORE2((i + 12))
134  CORE4(0);
135  CORE4(16);
136  CORE4(32);
137  CORE4(48);
138 #endif
139 
140  ABCD[0] += d;
141  ABCD[1] += c;
142  ABCD[2] += b;
143  ABCD[3] += a;
144  }
145 }
146 
148 {
149  ctx->len = 0;
150 
151  ctx->ABCD[0] = 0x10325476;
152  ctx->ABCD[1] = 0x98badcfe;
153  ctx->ABCD[2] = 0xefcdab89;
154  ctx->ABCD[3] = 0x67452301;
155 }
156 
157 void av_md5_update(AVMD5 *ctx, const uint8_t *src, int len)
158 {
159  const uint8_t *end;
160  int j;
161 
162  j = ctx->len & 63;
163  ctx->len += len;
164 
165  if (j) {
166  int cnt = FFMIN(len, 64 - j);
167  memcpy(ctx->block + j, src, cnt);
168  src += cnt;
169  len -= cnt;
170  if (j + cnt < 64)
171  return;
172  body(ctx->ABCD, (uint32_t *)ctx->block, 1);
173  }
174 
175  end = src + (len & ~63);
176  if (HAVE_BIGENDIAN || (!HAVE_FAST_UNALIGNED && ((intptr_t)src & 3))) {
177  while (src < end) {
178  memcpy(ctx->block, src, 64);
179  body(ctx->ABCD, (uint32_t *) ctx->block, 1);
180  src += 64;
181  }
182  } else {
183  int nblocks = len / 64;
184  body(ctx->ABCD, (uint32_t *)src, nblocks);
185  src = end;
186  }
187  len &= 63;
188  if (len > 0)
189  memcpy(ctx->block, src, len);
190 }
191 
193 {
194  int i;
195  uint64_t finalcount = av_le2ne64(ctx->len << 3);
196 
197  av_md5_update(ctx, "\200", 1);
198  while ((ctx->len & 63) != 56)
199  av_md5_update(ctx, "", 1);
200 
201  av_md5_update(ctx, (uint8_t *) &finalcount, 8);
202 
203  for (i = 0; i < 4; i++)
204  AV_WL32(dst + 4 * i, ctx->ABCD[3 - i]);
205 }
206 
207 void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
208 {
209  AVMD5 ctx;
210 
211  av_md5_init(&ctx);
212  av_md5_update(&ctx, src, len);
213  av_md5_final(&ctx, dst);
214 }
static const uint32_t T[64]
Definition: md5.c:60
static const uint8_t S[4][4]
Definition: md5.c:53
memory handling functions
const char * b
Definition: vf_curves.c:113
void av_md5_update(AVMD5 *ctx, const uint8_t *src, int len)
Update hash value.
Definition: md5.c:157
struct AVMD5 * av_md5_alloc(void)
Allocate an AVMD5 context.
Definition: md5.c:48
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
const int av_md5_size
Definition: md5.c:46
void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
Hash an array of data.
Definition: md5.c:207
Definition: md5.c:40
static void body(uint32_t ABCD[4], uint32_t *src, int nblocks)
Definition: md5.c:101
#define FFMIN(a, b)
Definition: common.h:96
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t block[64]
Definition: md5.c:42
int n
Definition: avisynth_c.h:547
#define src
Definition: vp9dsp.c:530
#define CORE4(i)
#define av_bswap32
Definition: bswap.h:33
void av_md5_init(AVMD5 *ctx)
Initialize MD5 hashing.
Definition: md5.c:147
uint64_t len
Definition: md5.c:41
#define av_le2ne64(x)
Definition: bswap.h:97
byte swapping routines
#define CORE(i, a, b, c, d)
Definition: md5.c:82
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
Finish hashing and output digest value.
Definition: md5.c:192
uint32_t ABCD[4]
Definition: md5.c:43
static double c[64]
int len
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:252
#define av_unused
Definition: attributes.h:126
#define AV_WL32(p, v)
Definition: intreadwrite.h:426