aboutsummaryrefslogtreecommitdiffstats
path: root/libavutil/md5.c
blob: 21a6e57098da7c5aacf018cb297d91e55314c7af (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
/*
 * Copyright (C) 2006 Michael Niedermayer (michaelni@gmx.at)
 * Copyright (C) 2003-2005 by Christopher R. Hertel (crh@ubiqx.mn.org)
 *
 * References:
 *  IETF RFC 1321: The MD5 Message-Digest Algorithm
 *       Ron Rivest. IETF, April, 1992
 *
 * based on http://ubiqx.org/libcifs/source/Auth/MD5.c
 *          from Christopher R. Hertel (crh@ubiqx.mn.org)
 * Simplified, cleaned and IMO redundant comments removed by michael.
 *
 * If you use gcc, then version 4.1 or later and -fomit-frame-pointer is
 * strongly recommended.
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdint.h>
#include "bswap.h"
#include "intreadwrite.h"
#include "md5.h"
#include "mem.h"

typedef struct AVMD5{
    uint64_t len;
    uint8_t  block[64];
    uint32_t ABCD[4];
} AVMD5;

const int av_md5_size = sizeof(AVMD5);

struct AVMD5 *av_md5_alloc(void)
{
    return av_mallocz(sizeof(struct AVMD5));
}

static const uint8_t S[4][4] = {
    { 7, 12, 17, 22 },  /* round 1 */
    { 5,  9, 14, 20 },  /* round 2 */
    { 4, 11, 16, 23 },  /* round 3 */
    { 6, 10, 15, 21 }   /* round 4 */
};

static const uint32_t T[64] = { // T[i]= fabs(sin(i+1)<<32)
    0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,   /* round 1 */
    0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
    0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
    0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,

    0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,   /* round 2 */
    0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
    0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
    0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,

    0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,   /* round 3 */
    0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
    0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
    0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,

    0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,   /* round 4 */
    0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
    0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
    0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391,
};

#define CORE(i, a, b, c, d) do {                                        \
        t = S[i >> 4][i & 3];                                           \
        a += T[i];                                                      \
                                                                        \
        if (i < 32) {                                                   \
            if (i < 16) a += (d ^ (b & (c ^ d))) + X[       i  & 15];   \
            else        a += ((d & b) | (~d & c))+ X[(1 + 5*i) & 15];   \
        } else {                                                        \
            if (i < 48) a += (b ^ c ^ d)         + X[(5 + 3*i) & 15];   \
            else        a += (c ^ (b | ~d))      + X[(    7*i) & 15];   \
        }                                                               \
        a = b + (a << t | a >> (32 - t));                               \
    } while (0)

static void body(uint32_t ABCD[4], uint32_t *src, int nblocks)
{
    int i av_unused;
    int n;
    uint32_t a, b, c, d, t, *X;

    for (n = 0; n < nblocks; n++) {
        a = ABCD[3];
        b = ABCD[2];
        c = ABCD[1];
        d = ABCD[0];

        X = src + n * 16;

#if HAVE_BIGENDIAN
    for (i = 0; i < 16; i++)
        X[i] = av_bswap32(X[i]);
#endif

#if CONFIG_SMALL
    for (i = 0; i < 64; i++) {
        CORE(i, a, b, c, d);
        t = d;
        d = c;
        c = b;
        b = a;
        a = t;
    }
#else
#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)
#define CORE4(i) CORE2(i); CORE2((i+4)); CORE2((i+8)); CORE2((i+12))
    CORE4(0); CORE4(16); CORE4(32); CORE4(48);
#endif

    ABCD[0] += d;
    ABCD[1] += c;
    ABCD[2] += b;
    ABCD[3] += a;
    }
}

void av_md5_init(AVMD5 *ctx)
{
    ctx->len     = 0;

    ctx->ABCD[0] = 0x10325476;
    ctx->ABCD[1] = 0x98badcfe;
    ctx->ABCD[2] = 0xefcdab89;
    ctx->ABCD[3] = 0x67452301;
}

void av_md5_update(AVMD5 *ctx, const uint8_t *src, int len)
{
    const uint8_t *end;
    int j;

    j = ctx->len & 63;
    ctx->len += len;

    if (j) {
        int cnt = FFMIN(len, 64 - j);
        memcpy(ctx->block + j, src, cnt);
        src += cnt;
        len -= cnt;
        if (j + cnt < 64)
            return;
        body(ctx->ABCD, (uint32_t *)ctx->block, 1);
    }

    end = src + (len & ~63);
    if (HAVE_BIGENDIAN || (!HAVE_FAST_UNALIGNED && ((intptr_t)src & 3))) {
       while (src < end) {
           memcpy(ctx->block, src, 64);
           body(ctx->ABCD, (uint32_t *) ctx->block, 1);
           src += 64;
        }
    } else {
        int nblocks = len / 64;
        body(ctx->ABCD, (uint32_t *)src, nblocks);
        src = end;
    }
    len &= 63;
    if (len > 0)
        memcpy(ctx->block, src, len);
}

void av_md5_final(AVMD5 *ctx, uint8_t *dst)
{
    int i;
    uint64_t finalcount = av_le2ne64(ctx->len << 3);

    av_md5_update(ctx, "\200", 1);
    while ((ctx->len & 63) != 56)
        av_md5_update(ctx, "", 1);

    av_md5_update(ctx, (uint8_t *)&finalcount, 8);

    for (i = 0; i < 4; i++)
        AV_WL32(dst + 4*i, ctx->ABCD[3 - i]);
}

void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
{
    AVMD5 ctx;

    av_md5_init(&ctx);
    av_md5_update(&ctx, src, len);
    av_md5_final(&ctx, dst);
}

#ifdef TEST
#include <stdio.h>

static void print_md5(uint8_t *md5)
{
    int i;
    for (i = 0; i < 16; i++)
        printf("%02x", md5[i]);
    printf("\n");
}

int main(void){
    uint8_t md5val[16];
    int i;
    uint8_t in[1000];

    for (i = 0; i < 1000; i++)
        in[i] = i * i;
    av_md5_sum(md5val, in, 1000); print_md5(md5val);
    av_md5_sum(md5val, in,   63); print_md5(md5val);
    av_md5_sum(md5val, in,   64); print_md5(md5val);
    av_md5_sum(md5val, in,   65); print_md5(md5val);
    for (i = 0; i < 1000; i++)
        in[i] = i % 127;
    av_md5_sum(md5val, in,  999); print_md5(md5val);

    return 0;
}
#endif