1 /*****************************************************************************
2 * md5.c: not so strong MD5 hashing
3 *****************************************************************************
4 * Copyright (C) 1995,1996,1998,1999,2001,2002,
5 * 2003 Free Software Foundation, Inc.
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU Lesser General Public License as published by
9 * the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this program; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
20 *****************************************************************************/
21
22 /* md5.c - MD5 Message-Digest Algorithm
23 *
24 * According to the definition of MD5 in RFC 1321 from April 1992.
25 * NOTE: This is *not* the same file as the one from glibc.
26 * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
27 * heavily modified for GnuPG by Werner Koch <wk@gnupg.org>
28 */
29
30 /* Test values:
31 * "" D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E
32 * "a" 0C C1 75 B9 C0 F1 B6 A8 31 C3 99 E2 69 77 26 61
33 * "abc 90 01 50 98 3C D2 4F B0 D6 96 3F 7D 28 E1 7F 72
34 * "message digest" F9 6B 69 7D 7C B7 93 8D 52 5A 2F 31 AA F1 61 D0
35 */
36
37 #ifdef HAVE_CONFIG_H
38 # include "config.h"
39 #endif
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43
44 #include <vlc_common.h>
45 #include <vlc_md5.h>
46
47 typedef uint32_t u32;
48 typedef uint8_t byte;
49 #define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
50
51 typedef struct md5_s MD5_CONTEXT;
52
53
54 static void
md5_init(void * context)55 md5_init( void *context )
56 {
57 MD5_CONTEXT *ctx = context;
58
59 ctx->A = 0x67452301;
60 ctx->B = 0xefcdab89;
61 ctx->C = 0x98badcfe;
62 ctx->D = 0x10325476;
63
64 ctx->nblocks = 0;
65 ctx->count = 0;
66 }
67
68
69 /* These are the four functions used in the four steps of the MD5 algorithm
70 and defined in the RFC 1321. The first function is a little bit optimized
71 (as found in Colin Plumbs public domain implementation). */
72 /* #define FF(b, c, d) ((b & c) | (~b & d)) */
73 #define FF(b, c, d) (d ^ (b & (c ^ d)))
74 #define FG(b, c, d) FF (d, b, c)
75 #define FH(b, c, d) (b ^ c ^ d)
76 #define FI(b, c, d) (c ^ (b | ~d))
77
78
79 /****************
80 * transform n*64 bytes
81 */
82 static void
transform(MD5_CONTEXT * ctx,const unsigned char * data)83 transform ( MD5_CONTEXT *ctx, const unsigned char *data )
84 {
85 u32 correct_words[16];
86 register u32 A = ctx->A;
87 register u32 B = ctx->B;
88 register u32 C = ctx->C;
89 register u32 D = ctx->D;
90 u32 *cwp = correct_words;
91
92 #ifdef WORDS_BIGENDIAN
93 {
94 int i;
95 byte *p2, *p1;
96 for(i=0, p1=data, p2=(byte*)correct_words; i < 16; i++, p2 += 4 )
97 {
98 p2[3] = *p1++;
99 p2[2] = *p1++;
100 p2[1] = *p1++;
101 p2[0] = *p1++;
102 }
103 }
104 #else
105 memcpy( correct_words, data, 64 );
106 #endif
107
108
109 #define OP(a, b, c, d, s, T) \
110 do \
111 { \
112 a += FF (b, c, d) + (*cwp++) + T; \
113 a = rol(a, s); \
114 a += b; \
115 } \
116 while (0)
117
118 /* Before we start, one word about the strange constants.
119 They are defined in RFC 1321 as
120
121 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
122 */
123
124 /* Round 1. */
125 OP (A, B, C, D, 7, 0xd76aa478);
126 OP (D, A, B, C, 12, 0xe8c7b756);
127 OP (C, D, A, B, 17, 0x242070db);
128 OP (B, C, D, A, 22, 0xc1bdceee);
129 OP (A, B, C, D, 7, 0xf57c0faf);
130 OP (D, A, B, C, 12, 0x4787c62a);
131 OP (C, D, A, B, 17, 0xa8304613);
132 OP (B, C, D, A, 22, 0xfd469501);
133 OP (A, B, C, D, 7, 0x698098d8);
134 OP (D, A, B, C, 12, 0x8b44f7af);
135 OP (C, D, A, B, 17, 0xffff5bb1);
136 OP (B, C, D, A, 22, 0x895cd7be);
137 OP (A, B, C, D, 7, 0x6b901122);
138 OP (D, A, B, C, 12, 0xfd987193);
139 OP (C, D, A, B, 17, 0xa679438e);
140 OP (B, C, D, A, 22, 0x49b40821);
141
142 #undef OP
143 #define OP(f, a, b, c, d, k, s, T) \
144 do \
145 { \
146 a += f (b, c, d) + correct_words[k] + T; \
147 a = rol(a, s); \
148 a += b; \
149 } \
150 while (0)
151
152 /* Round 2. */
153 OP (FG, A, B, C, D, 1, 5, 0xf61e2562);
154 OP (FG, D, A, B, C, 6, 9, 0xc040b340);
155 OP (FG, C, D, A, B, 11, 14, 0x265e5a51);
156 OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
157 OP (FG, A, B, C, D, 5, 5, 0xd62f105d);
158 OP (FG, D, A, B, C, 10, 9, 0x02441453);
159 OP (FG, C, D, A, B, 15, 14, 0xd8a1e681);
160 OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
161 OP (FG, A, B, C, D, 9, 5, 0x21e1cde6);
162 OP (FG, D, A, B, C, 14, 9, 0xc33707d6);
163 OP (FG, C, D, A, B, 3, 14, 0xf4d50d87);
164 OP (FG, B, C, D, A, 8, 20, 0x455a14ed);
165 OP (FG, A, B, C, D, 13, 5, 0xa9e3e905);
166 OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8);
167 OP (FG, C, D, A, B, 7, 14, 0x676f02d9);
168 OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
169
170 /* Round 3. */
171 OP (FH, A, B, C, D, 5, 4, 0xfffa3942);
172 OP (FH, D, A, B, C, 8, 11, 0x8771f681);
173 OP (FH, C, D, A, B, 11, 16, 0x6d9d6122);
174 OP (FH, B, C, D, A, 14, 23, 0xfde5380c);
175 OP (FH, A, B, C, D, 1, 4, 0xa4beea44);
176 OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9);
177 OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60);
178 OP (FH, B, C, D, A, 10, 23, 0xbebfbc70);
179 OP (FH, A, B, C, D, 13, 4, 0x289b7ec6);
180 OP (FH, D, A, B, C, 0, 11, 0xeaa127fa);
181 OP (FH, C, D, A, B, 3, 16, 0xd4ef3085);
182 OP (FH, B, C, D, A, 6, 23, 0x04881d05);
183 OP (FH, A, B, C, D, 9, 4, 0xd9d4d039);
184 OP (FH, D, A, B, C, 12, 11, 0xe6db99e5);
185 OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8);
186 OP (FH, B, C, D, A, 2, 23, 0xc4ac5665);
187
188 /* Round 4. */
189 OP (FI, A, B, C, D, 0, 6, 0xf4292244);
190 OP (FI, D, A, B, C, 7, 10, 0x432aff97);
191 OP (FI, C, D, A, B, 14, 15, 0xab9423a7);
192 OP (FI, B, C, D, A, 5, 21, 0xfc93a039);
193 OP (FI, A, B, C, D, 12, 6, 0x655b59c3);
194 OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92);
195 OP (FI, C, D, A, B, 10, 15, 0xffeff47d);
196 OP (FI, B, C, D, A, 1, 21, 0x85845dd1);
197 OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f);
198 OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
199 OP (FI, C, D, A, B, 6, 15, 0xa3014314);
200 OP (FI, B, C, D, A, 13, 21, 0x4e0811a1);
201 OP (FI, A, B, C, D, 4, 6, 0xf7537e82);
202 OP (FI, D, A, B, C, 11, 10, 0xbd3af235);
203 OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
204 OP (FI, B, C, D, A, 9, 21, 0xeb86d391);
205
206 /* Put checksum in context given as argument. */
207 ctx->A += A;
208 ctx->B += B;
209 ctx->C += C;
210 ctx->D += D;
211 }
212
213
214
215 /* The routine updates the message-digest context to
216 * account for the presence of each of the characters inBuf[0..inLen-1]
217 * in the message whose digest is being computed.
218 */
219 static void
md5_write(void * context,const void * inbuf_arg,size_t inlen)220 md5_write( void *context, const void *inbuf_arg , size_t inlen)
221 {
222 const unsigned char *inbuf = inbuf_arg;
223 MD5_CONTEXT *hd = context;
224
225 if( hd->count == 64 ) /* flush the buffer */
226 {
227 transform( hd, hd->buf );
228 hd->count = 0;
229 hd->nblocks++;
230 }
231 if( !inbuf )
232 return;
233
234 if( hd->count )
235 {
236 for( ; inlen && hd->count < 64; inlen-- )
237 hd->buf[hd->count++] = *inbuf++;
238 md5_write( hd, NULL, 0 );
239 if( !inlen )
240 return;
241 }
242
243 while( inlen >= 64 )
244 {
245 transform( hd, inbuf );
246 hd->count = 0;
247 hd->nblocks++;
248 inlen -= 64;
249 inbuf += 64;
250 }
251 for( ; inlen && hd->count < 64; inlen-- )
252 hd->buf[hd->count++] = *inbuf++;
253
254 }
255
256
257
258 /* The routine final terminates the message-digest computation and
259 * ends with the desired message digest in mdContext->digest[0...15].
260 * The handle is prepared for a new MD5 cycle.
261 * Returns 16 bytes representing the digest.
262 */
263
264 static void
md5_final(void * context)265 md5_final( void *context)
266 {
267 MD5_CONTEXT *hd = context;
268 u32 t, msb, lsb;
269 byte *p;
270
271 md5_write(hd, NULL, 0); /* flush */;
272
273 t = hd->nblocks;
274 /* multiply by 64 to make a byte count */
275 lsb = t << 6;
276 msb = t >> 26;
277 /* add the count */
278 t = lsb;
279 if( (lsb += hd->count) < t )
280 msb++;
281 /* multiply by 8 to make a bit count */
282 t = lsb;
283 lsb <<= 3;
284 msb <<= 3;
285 msb |= t >> 29;
286
287 if( hd->count < 56 ) /* enough room */
288 {
289 hd->buf[hd->count++] = 0x80; /* pad */
290 while( hd->count < 56 )
291 hd->buf[hd->count++] = 0; /* pad */
292 }
293 else /* need one extra block */
294 {
295 hd->buf[hd->count++] = 0x80; /* pad character */
296 while( hd->count < 64 )
297 hd->buf[hd->count++] = 0;
298 md5_write(hd, NULL, 0); /* flush */;
299 memset(hd->buf, 0, 56 ); /* fill next block with zeroes */
300 }
301 /* append the 64 bit count */
302 hd->buf[56] = lsb ;
303 hd->buf[57] = lsb >> 8;
304 hd->buf[58] = lsb >> 16;
305 hd->buf[59] = lsb >> 24;
306 hd->buf[60] = msb ;
307 hd->buf[61] = msb >> 8;
308 hd->buf[62] = msb >> 16;
309 hd->buf[63] = msb >> 24;
310 transform( hd, hd->buf );
311
312 p = hd->buf;
313 #ifdef WORDS_BIGENDIAN
314 #define X(a) do { *p++ = hd->a ; *p++ = hd->a >> 8; \
315 *p++ = hd->a >> 16; *p++ = hd->a >> 24; } while(0)
316 #else /* little endian */
317 #define X(a) do { *(u32*)p = (*hd).a ; p += 4; } while(0)
318 #endif
319 X(A);
320 X(B);
321 X(C);
322 X(D);
323 #undef X
324
325 }
326
327 #if 0
328 static byte *
329 md5_read( void *context )
330 {
331 MD5_CONTEXT *hd = (MD5_CONTEXT *) context;
332 return hd->buf;
333 }
334 #endif
335
InitMD5(struct md5_s * h)336 void InitMD5( struct md5_s *h )
337 {
338 md5_init( h );
339 }
340
AddMD5(struct md5_s * restrict h,const void * data,size_t len)341 void AddMD5( struct md5_s *restrict h, const void *data, size_t len )
342 {
343 md5_write( h, data, len );
344 }
345
EndMD5(struct md5_s * h)346 void EndMD5( struct md5_s *h )
347 {
348 md5_final( h );
349 }
350