1 /* md5.c - MD5 Message-Digest Algorithm
2 * Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
4 * according to the definition of MD5 in RFC 1321 from April 1992.
5 * NOTE: This is *not* the same file as the one from glibc.
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2, or (at your option) any
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 General Public License for more details.
17 * You should have received a copy of the GNU 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.
21 /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. */
22 /* heavily modified for GnuPG by <werner.koch@guug.de> */
23 /* modified again for Sylpheed by <wk@gnupg.org> 2001-02-11 */
27 * "" D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E
28 * "a" 0C C1 75 B9 C0 F1 B6 A8 31 C3 99 E2 69 77 26 61
29 * "abc 90 01 50 98 3C D2 4F B0 D6 96 3F 7D 28 E1 7F 72
30 * "message digest" F9 6B 69 7D 7C B7 93 8D 52 5A 2F 31 AA F1 61 D0
42 * Rotate a 32 bit integer by n bytes
44 #if defined(__GNUC__) && defined(__i386__)
48 __asm__("roll %%cl,%0"
54 #define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
59 md5_init(MD5_CONTEXT *ctx)
71 /* These are the four functions used in the four steps of the MD5 algorithm
72 and defined in the RFC 1321. The first function is a little bit optimized
73 (as found in Colin Plumbs public domain implementation). */
74 /* #define FF(b, c, d) ((b & c) | (~b & d)) */
75 #define FF(b, c, d) (d ^ (b & (c ^ d)))
76 #define FG(b, c, d) FF (d, b, c)
77 #define FH(b, c, d) (b ^ c ^ d)
78 #define FI(b, c, d) (c ^ (b | ~d))
82 * transform n*64 bytes
85 transform(MD5_CONTEXT *ctx, const unsigned char *data)
87 u32 correct_words[16];
92 u32 *cwp = correct_words;
94 #ifdef BIG_ENDIAN_HOST
98 const unsigned char *p1;
100 for (i = 0, p1 = data, p2 = (unsigned char*)correct_words;
101 i < 16; i++, p2 += 4) {
109 memcpy(correct_words, data, 64);
113 #define OP(a, b, c, d, s, T) \
115 a += FF (b, c, d) + (*cwp++) + T; \
120 /* Before we start, one word about the strange constants.
121 They are defined in RFC 1321 as
123 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
127 OP (A, B, C, D, 7, 0xd76aa478);
128 OP (D, A, B, C, 12, 0xe8c7b756);
129 OP (C, D, A, B, 17, 0x242070db);
130 OP (B, C, D, A, 22, 0xc1bdceee);
131 OP (A, B, C, D, 7, 0xf57c0faf);
132 OP (D, A, B, C, 12, 0x4787c62a);
133 OP (C, D, A, B, 17, 0xa8304613);
134 OP (B, C, D, A, 22, 0xfd469501);
135 OP (A, B, C, D, 7, 0x698098d8);
136 OP (D, A, B, C, 12, 0x8b44f7af);
137 OP (C, D, A, B, 17, 0xffff5bb1);
138 OP (B, C, D, A, 22, 0x895cd7be);
139 OP (A, B, C, D, 7, 0x6b901122);
140 OP (D, A, B, C, 12, 0xfd987193);
141 OP (C, D, A, B, 17, 0xa679438e);
142 OP (B, C, D, A, 22, 0x49b40821);
145 #define OP(f, a, b, c, d, k, s, T) \
147 a += f (b, c, d) + correct_words[k] + T; \
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);
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);
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);
206 /* Put checksum in context given as argument. */
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.
220 md5_update(MD5_CONTEXT *hd, const unsigned char *inbuf, size_t inlen)
222 if (hd->count == 64) { /* flush the buffer */
223 transform( hd, hd->buf );
230 for (; inlen && hd->count < 64; inlen--)
231 hd->buf[hd->count++] = *inbuf++;
232 md5_update(hd, NULL, 0);
237 while (inlen >= 64) {
238 transform(hd, inbuf);
245 for (; inlen && hd->count < 64; inlen--)
246 hd->buf[hd->count++] = *inbuf++;
251 /* The routine final terminates the message-digest computation and
252 * ends with the desired message digest in mdContext->digest[0...15].
253 * The handle is prepared for a new MD5 cycle.
254 * Returns 16 bytes representing the digest.
258 do_final(MD5_CONTEXT *hd)
263 md5_update(hd, NULL, 0); /* flush */
267 if ((lsb = t << 6) < t) /* multiply by 64 to make a byte count */
271 if ((lsb = t + hd->count) < t) /* add the count */
274 if ((lsb = t << 3) < t) /* multiply by 8 to make a bit count */
278 if (hd->count < 56) { /* enough room */
279 hd->buf[hd->count++] = 0x80; /* pad */
280 while(hd->count < 56)
281 hd->buf[hd->count++] = 0; /* pad */
282 } else { /* need one extra block */
283 hd->buf[hd->count++] = 0x80; /* pad character */
284 while (hd->count < 64)
285 hd->buf[hd->count++] = 0;
286 md5_update(hd, NULL, 0); /* flush */
287 memset(hd->buf, 0, 56); /* fill next block with zeroes */
290 /* append the 64 bit count */
292 hd->buf[57] = lsb >> 8;
293 hd->buf[58] = lsb >> 16;
294 hd->buf[59] = lsb >> 24;
296 hd->buf[61] = msb >> 8;
297 hd->buf[62] = msb >> 16;
298 hd->buf[63] = msb >> 24;
299 transform(hd, hd->buf);
302 #ifdef BIG_ENDIAN_HOST
303 #define X(a) do { *p++ = hd->a ; *p++ = hd->a >> 8; \
304 *p++ = hd->a >> 16; *p++ = hd->a >> 24; } while(0)
305 #else /* little endian */
306 /*#define X(a) do { *(u32*)p = hd->##a ; p += 4; } while(0)*/
307 /* Unixware's cpp doesn't like the above construct so we do it his way:
308 * (reported by Allan Clark) */
309 #define X(a) do { *(u32*)p = (*hd).a ; p += 4; } while(0)
320 md5_final(unsigned char *digest, MD5_CONTEXT *ctx)
324 memcpy(digest, ctx->buf, 16);
328 * Creates a MD5 digest in hex fomrat (lowercase letters) from the
329 * string S. hextdigest but be buffer of at lease 33 bytes!
332 md5_hex_digest(char *hexdigest, const unsigned char *s)
336 unsigned char digest[16];
339 md5_update(&context, s, strlen(s));
340 md5_final(digest, &context);
342 for (i = 0; i < 16; i++)
343 sprintf(hexdigest + 2 * i, "%02x", digest[i]);
348 ** Function: md5_hmac
349 ** taken from the file rfc2104.txt
350 ** written by Martin Schaaf <mascha@ma-scha.de>
353 md5_hmac(unsigned char *digest,
354 const unsigned char* text, int text_len,
355 const unsigned char* key, int key_len)
358 unsigned char k_ipad[64]; /* inner padding -
361 unsigned char k_opad[64]; /* outer padding -
364 /* unsigned char tk[16]; */
367 /* start out by storing key in pads */
368 memset(k_ipad, 0, sizeof k_ipad);
369 memset(k_opad, 0, sizeof k_opad);
371 /* if key is longer than 64 bytes reset it to key=MD5(key) */
375 md5_update(&tctx, key, key_len);
376 md5_final(k_ipad, &tctx);
377 md5_final(k_opad, &tctx);
379 memcpy(k_ipad, key, key_len);
380 memcpy(k_opad, key, key_len);
384 * the HMAC_MD5 transform looks like:
386 * MD5(K XOR opad, MD5(K XOR ipad, text))
388 * where K is an n byte key
389 * ipad is the byte 0x36 repeated 64 times
390 * opad is the byte 0x5c repeated 64 times
391 * and text is the data being protected
395 /* XOR key with ipad and opad values */
396 for (i = 0; i < 64; i++) {
404 md5_init(&context); /* init context for 1st
406 md5_update(&context, k_ipad, 64); /* start with inner pad */
407 md5_update(&context, text, text_len); /* then text of datagram */
408 md5_final(digest, &context); /* finish up 1st pass */
412 md5_init(&context); /* init context for 2nd
414 md5_update(&context, k_opad, 64); /* start with outer pad */
415 md5_update(&context, digest, 16); /* then results of 1st
417 md5_final(digest, &context); /* finish up 2nd pass */
422 md5_hex_hmac(char *hexdigest,
423 const unsigned char* text, int text_len,
424 const unsigned char* key, int key_len)
426 unsigned char digest[16];
429 md5_hmac(digest, text, text_len, key, key_len);
430 for (i = 0; i < 16; i++)
431 sprintf(hexdigest + 2 * i, "%02x", digest[i]);