1 /* -*- mode: c; c-basic-offset: 8; related-file-name: "../include/lcdf/md5.h" -*- */
2 /* md5.c - MD5 Message-Digest Algorithm
3 * Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
4 *
5 * according to the definition of MD5 in RFC 1321 from April 1992.
6 * NOTE: This is *not* the same file as the one from glibc.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2, or (at your option) any
11 * later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software Foundation,
20 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 */
22 /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. */
23 /* heavily modified for GnuPG by <werner.koch@guug.de> */
24 /* modified again for Sylpheed by <wk@gnupg.org> 2001-02-11 */
25 /* modified again for LCDF by Eddie Kohler <kohler@icir.org> */
26
27
28 /* Test values:
29 * "" D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E
30 * "a" 0C C1 75 B9 C0 F1 B6 A8 31 C3 99 E2 69 77 26 61
31 * "abc 90 01 50 98 3C D2 4F B0 D6 96 3F 7D 28 E1 7F 72
32 * "message digest" F9 6B 69 7D 7C B7 93 8D 52 5A 2F 31 AA F1 61 D0
33 */
34
35 #include <config.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <assert.h>
40 #include <lcdf/inttypes.h>
41 #include <lcdf/md5.h>
42
43 #ifdef __cplusplus
44 extern "C" {
45 #endif
46
47
48 /****************
49 * Rotate a 32 bit integer by n bits
50 */
51 #if defined(__GNUC__) && defined(__i386__)
52 static inline uint32_t
rol(uint32_t x,int n)53 rol( uint32_t x, int n)
54 {
55 __asm__("roll %%cl,%0"
56 :"=r" (x)
57 :"0" (x),"c" (n));
58 return x;
59 }
60 #else
61 #define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
62 #endif
63
64
65 void
md5_init(MD5_CONTEXT * ctx)66 md5_init(MD5_CONTEXT *ctx)
67 {
68 ctx->A = 0x67452301;
69 ctx->B = 0xefcdab89;
70 ctx->C = 0x98badcfe;
71 ctx->D = 0x10325476;
72
73 ctx->nblocks = 0;
74 ctx->count = 0;
75 ctx->finalized = 0;
76 }
77
78 /* These are the four functions used in the four steps of the MD5 algorithm
79 and defined in the RFC 1321. The first function is a little bit optimized
80 (as found in Colin Plumbs public domain implementation). */
81 /* #define FF(b, c, d) ((b & c) | (~b & d)) */
82 #define FF(b, c, d) (d ^ (b & (c ^ d)))
83 #define FG(b, c, d) FF (d, b, c)
84 #define FH(b, c, d) (b ^ c ^ d)
85 #define FI(b, c, d) (c ^ (b | ~d))
86
87
88 /****************
89 * transform n*64 bytes
90 */
91 static void
transform(MD5_CONTEXT * ctx,const unsigned char * data)92 transform(MD5_CONTEXT *ctx, const unsigned char *data)
93 {
94 uint32_t correct_words[16];
95 uint32_t A = ctx->A;
96 uint32_t B = ctx->B;
97 uint32_t C = ctx->C;
98 uint32_t D = ctx->D;
99 uint32_t *cwp = correct_words;
100
101 #if WORDS_BIGENDIAN
102 {
103 int i;
104 unsigned char *p2, *p1;
105
106 for (i = 0, p1 = data, p2 = (unsigned char*)correct_words;
107 i < 16; i++, p2 += 4) {
108 p2[3] = *p1++;
109 p2[2] = *p1++;
110 p2[1] = *p1++;
111 p2[0] = *p1++;
112 }
113 }
114 #elif WORDS_BIGENDIAN_SET
115 memcpy(correct_words, data, 64);
116 #else
117 # error "WORDS_BIGENDIAN has not been set!"
118 #endif
119
120
121 #define OP(a, b, c, d, s, T) \
122 do { \
123 a += FF (b, c, d) + (*cwp++) + T; \
124 a = rol(a, s); \
125 a += b; \
126 } while (0)
127
128 /* Before we start, one word about the strange constants.
129 They are defined in RFC 1321 as
130
131 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
132 */
133
134 /* Round 1. */
135 OP (A, B, C, D, 7, 0xd76aa478);
136 OP (D, A, B, C, 12, 0xe8c7b756);
137 OP (C, D, A, B, 17, 0x242070db);
138 OP (B, C, D, A, 22, 0xc1bdceee);
139 OP (A, B, C, D, 7, 0xf57c0faf);
140 OP (D, A, B, C, 12, 0x4787c62a);
141 OP (C, D, A, B, 17, 0xa8304613);
142 OP (B, C, D, A, 22, 0xfd469501);
143 OP (A, B, C, D, 7, 0x698098d8);
144 OP (D, A, B, C, 12, 0x8b44f7af);
145 OP (C, D, A, B, 17, 0xffff5bb1);
146 OP (B, C, D, A, 22, 0x895cd7be);
147 OP (A, B, C, D, 7, 0x6b901122);
148 OP (D, A, B, C, 12, 0xfd987193);
149 OP (C, D, A, B, 17, 0xa679438e);
150 OP (B, C, D, A, 22, 0x49b40821);
151
152 #undef OP
153 #define OP(f, a, b, c, d, k, s, T) \
154 do { \
155 a += f (b, c, d) + correct_words[k] + T; \
156 a = rol(a, s); \
157 a += b; \
158 } while (0)
159
160 /* Round 2. */
161 OP (FG, A, B, C, D, 1, 5, 0xf61e2562);
162 OP (FG, D, A, B, C, 6, 9, 0xc040b340);
163 OP (FG, C, D, A, B, 11, 14, 0x265e5a51);
164 OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
165 OP (FG, A, B, C, D, 5, 5, 0xd62f105d);
166 OP (FG, D, A, B, C, 10, 9, 0x02441453);
167 OP (FG, C, D, A, B, 15, 14, 0xd8a1e681);
168 OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
169 OP (FG, A, B, C, D, 9, 5, 0x21e1cde6);
170 OP (FG, D, A, B, C, 14, 9, 0xc33707d6);
171 OP (FG, C, D, A, B, 3, 14, 0xf4d50d87);
172 OP (FG, B, C, D, A, 8, 20, 0x455a14ed);
173 OP (FG, A, B, C, D, 13, 5, 0xa9e3e905);
174 OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8);
175 OP (FG, C, D, A, B, 7, 14, 0x676f02d9);
176 OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
177
178 /* Round 3. */
179 OP (FH, A, B, C, D, 5, 4, 0xfffa3942);
180 OP (FH, D, A, B, C, 8, 11, 0x8771f681);
181 OP (FH, C, D, A, B, 11, 16, 0x6d9d6122);
182 OP (FH, B, C, D, A, 14, 23, 0xfde5380c);
183 OP (FH, A, B, C, D, 1, 4, 0xa4beea44);
184 OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9);
185 OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60);
186 OP (FH, B, C, D, A, 10, 23, 0xbebfbc70);
187 OP (FH, A, B, C, D, 13, 4, 0x289b7ec6);
188 OP (FH, D, A, B, C, 0, 11, 0xeaa127fa);
189 OP (FH, C, D, A, B, 3, 16, 0xd4ef3085);
190 OP (FH, B, C, D, A, 6, 23, 0x04881d05);
191 OP (FH, A, B, C, D, 9, 4, 0xd9d4d039);
192 OP (FH, D, A, B, C, 12, 11, 0xe6db99e5);
193 OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8);
194 OP (FH, B, C, D, A, 2, 23, 0xc4ac5665);
195
196 /* Round 4. */
197 OP (FI, A, B, C, D, 0, 6, 0xf4292244);
198 OP (FI, D, A, B, C, 7, 10, 0x432aff97);
199 OP (FI, C, D, A, B, 14, 15, 0xab9423a7);
200 OP (FI, B, C, D, A, 5, 21, 0xfc93a039);
201 OP (FI, A, B, C, D, 12, 6, 0x655b59c3);
202 OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92);
203 OP (FI, C, D, A, B, 10, 15, 0xffeff47d);
204 OP (FI, B, C, D, A, 1, 21, 0x85845dd1);
205 OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f);
206 OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
207 OP (FI, C, D, A, B, 6, 15, 0xa3014314);
208 OP (FI, B, C, D, A, 13, 21, 0x4e0811a1);
209 OP (FI, A, B, C, D, 4, 6, 0xf7537e82);
210 OP (FI, D, A, B, C, 11, 10, 0xbd3af235);
211 OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
212 OP (FI, B, C, D, A, 9, 21, 0xeb86d391);
213
214 /* Put checksum in context given as argument. */
215 ctx->A += A;
216 ctx->B += B;
217 ctx->C += C;
218 ctx->D += D;
219 }
220
221
222
223 /* The routine updates the message-digest context to
224 * account for the presence of each of the characters inBuf[0..inLen-1]
225 * in the message whose digest is being computed.
226 */
227 void
md5_update(MD5_CONTEXT * hd,const unsigned char * inbuf,size_t inlen)228 md5_update(MD5_CONTEXT *hd, const unsigned char *inbuf, size_t inlen)
229 {
230 if (hd->count == 64) { /* flush the buffer */
231 transform( hd, hd->buf );
232 hd->count = 0;
233 hd->nblocks++;
234 }
235 if (!inbuf)
236 return;
237 if (hd->count) {
238 for (; inlen && hd->count < 64; inlen--)
239 hd->buf[hd->count++] = *inbuf++;
240 md5_update(hd, NULL, 0);
241 if (!inlen)
242 return;
243 }
244
245 while (inlen >= 64) {
246 transform(hd, inbuf);
247 hd->count = 0;
248 hd->nblocks++;
249 inlen -= 64;
250 inbuf += 64;
251 }
252
253 for (; inlen && hd->count < 64; inlen--)
254 hd->buf[hd->count++] = *inbuf++;
255 }
256
257
258
259 /* The routine final terminates the message-digest computation and
260 * ends with the desired message digest in mdContext->digest[0...15].
261 * The handle is prepared for a new MD5 cycle.
262 * Returns 16 bytes representing the digest.
263 */
264
265 static void
do_final(MD5_CONTEXT * hd)266 do_final(MD5_CONTEXT *hd)
267 {
268 uint32_t t, msb, lsb;
269 unsigned char *p;
270
271 md5_update(hd, NULL, 0); /* flush */
272
273 msb = 0;
274 t = hd->nblocks;
275 if ((lsb = t << 6) < t) /* multiply by 64 to make a byte count */
276 msb++;
277 msb += t >> 26;
278 t = lsb;
279 if ((lsb = t + hd->count) < t) /* add the count */
280 msb++;
281 t = lsb;
282 if ((lsb = t << 3) < t) /* multiply by 8 to make a bit count */
283 msb++;
284 msb += t >> 29;
285
286 if (hd->count < 56) { /* enough room */
287 hd->buf[hd->count++] = 0x80; /* pad */
288 while(hd->count < 56)
289 hd->buf[hd->count++] = 0; /* pad */
290 } else { /* need one extra block */
291 hd->buf[hd->count++] = 0x80; /* pad character */
292 while (hd->count < 64)
293 hd->buf[hd->count++] = 0;
294 md5_update(hd, NULL, 0); /* flush */
295 memset(hd->buf, 0, 56); /* fill next block with zeroes */
296 }
297
298 /* append the 64 bit count */
299 hd->buf[56] = lsb ;
300 hd->buf[57] = lsb >> 8;
301 hd->buf[58] = lsb >> 16;
302 hd->buf[59] = lsb >> 24;
303 hd->buf[60] = msb ;
304 hd->buf[61] = msb >> 8;
305 hd->buf[62] = msb >> 16;
306 hd->buf[63] = msb >> 24;
307 transform(hd, hd->buf);
308
309 p = hd->buf;
310 #if WORDS_BIGENDIAN
311 #define X(a) do { *p++ = hd->a ; *p++ = hd->a >> 8; \
312 *p++ = hd->a >> 16; *p++ = hd->a >> 24; } while(0)
313 #elif WORDS_BIGENDIAN_SET
314 /*#define X(a) do { *(uint32_t*)p = hd->##a ; p += 4; } while(0)*/
315 /* Unixware's cpp doesn't like the above construct so we do it his way:
316 * (reported by Allan Clark) */
317 #define X(a) do { *(uint32_t*)p = (*hd).a ; p += 4; } while(0)
318 #else
319 # error "WORDS_BIGENDIAN has not been set!"
320 #endif
321 X(A);
322 X(B);
323 X(C);
324 X(D);
325 #undef X
326 hd->finalized = 1;
327 }
328
329 void
md5_final(unsigned char * digest,MD5_CONTEXT * ctx)330 md5_final(unsigned char *digest, MD5_CONTEXT *ctx)
331 {
332 if (!ctx->finalized)
333 do_final(ctx);
334 memcpy(digest, ctx->buf, 16);
335 }
336
337 void
md5_final_text(char * buf,MD5_CONTEXT * ctx)338 md5_final_text(char *buf, MD5_CONTEXT *ctx)
339 {
340 static const char *chars = "abcdefghijklmnopqrstuvwxyz234567";
341 int bit;
342 if (!ctx->finalized)
343 do_final(ctx);
344 for (bit = 0; bit < 16*8; bit += 5) {
345 int first_char = bit / 8;
346 int val = ctx->buf[first_char] >> (bit % 8);
347 if (bit + 8 > (first_char + 1) * 8 && first_char < 15)
348 val += ctx->buf[first_char + 1] << (8 - (bit % 8));
349 *buf++ = chars[val & 0x1F];
350 }
351 *buf++ = 0;
352 }
353
354
355 #ifdef __cplusplus
356 }
357 #endif
358