1 /*
2 Copyright (C) 1999 Aladdin Enterprises. All rights reserved.
3
4 This software is provided 'as-is', without any express or implied
5 warranty. In no event will the authors be held liable for any damages
6 arising from the use of this software.
7
8 Permission is granted to anyone to use this software for any purpose,
9 including commercial applications, and to alter it and redistribute it
10 freely, subject to the following restrictions:
11
12 1. The origin of this software must not be misrepresented; you must not
13 claim that you wrote the original software. If you use this software
14 in a product, an acknowledgment in the product documentation would be
15 appreciated but is not required.
16 2. Altered source versions must be plainly marked as such, and must not be
17 misrepresented as being the original software.
18 3. This notice may not be removed or altered from any source distribution.
19
20 L. Peter Deutsch
21 ghost@aladdin.com
22
23 */
24 /*
25 Independent implementation of MD5 (RFC 1321).
26
27 This code implements the MD5 Algorithm defined in RFC 1321.
28 It is derived directly from the text of the RFC and not from the
29 reference implementation.
30
31 The original and principal author of md5.c is L. Peter Deutsch
32 <ghost@aladdin.com>. Other authors are noted in the change history
33 that follows (in reverse chronological order):
34
35 1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
36 1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5).
37 1999-05-03 lpd Original version.
38 */
39
40 #include "md5.h"
41 #include <string.h>
42
43 #define T1 0xd76aa478
44 #define T2 0xe8c7b756
45 #define T3 0x242070db
46 #define T4 0xc1bdceee
47 #define T5 0xf57c0faf
48 #define T6 0x4787c62a
49 #define T7 0xa8304613
50 #define T8 0xfd469501
51 #define T9 0x698098d8
52 #define T10 0x8b44f7af
53 #define T11 0xffff5bb1
54 #define T12 0x895cd7be
55 #define T13 0x6b901122
56 #define T14 0xfd987193
57 #define T15 0xa679438e
58 #define T16 0x49b40821
59 #define T17 0xf61e2562
60 #define T18 0xc040b340
61 #define T19 0x265e5a51
62 #define T20 0xe9b6c7aa
63 #define T21 0xd62f105d
64 #define T22 0x02441453
65 #define T23 0xd8a1e681
66 #define T24 0xe7d3fbc8
67 #define T25 0x21e1cde6
68 #define T26 0xc33707d6
69 #define T27 0xf4d50d87
70 #define T28 0x455a14ed
71 #define T29 0xa9e3e905
72 #define T30 0xfcefa3f8
73 #define T31 0x676f02d9
74 #define T32 0x8d2a4c8a
75 #define T33 0xfffa3942
76 #define T34 0x8771f681
77 #define T35 0x6d9d6122
78 #define T36 0xfde5380c
79 #define T37 0xa4beea44
80 #define T38 0x4bdecfa9
81 #define T39 0xf6bb4b60
82 #define T40 0xbebfbc70
83 #define T41 0x289b7ec6
84 #define T42 0xeaa127fa
85 #define T43 0xd4ef3085
86 #define T44 0x04881d05
87 #define T45 0xd9d4d039
88 #define T46 0xe6db99e5
89 #define T47 0x1fa27cf8
90 #define T48 0xc4ac5665
91 #define T49 0xf4292244
92 #define T50 0x432aff97
93 #define T51 0xab9423a7
94 #define T52 0xfc93a039
95 #define T53 0x655b59c3
96 #define T54 0x8f0ccc92
97 #define T55 0xffeff47d
98 #define T56 0x85845dd1
99 #define T57 0x6fa87e4f
100 #define T58 0xfe2ce6e0
101 #define T59 0xa3014314
102 #define T60 0x4e0811a1
103 #define T61 0xf7537e82
104 #define T62 0xbd3af235
105 #define T63 0x2ad7d2bb
106 #define T64 0xeb86d391
107
108 static void
md5_process(md5_state_t * pms,const md5_byte_t * data)109 md5_process(md5_state_t *pms, const md5_byte_t *data /*[64]*/)
110 {
111 md5_word_t
112 a = pms->abcd[0], b = pms->abcd[1],
113 c = pms->abcd[2], d = pms->abcd[3];
114 md5_word_t t;
115
116 /*
117 * On big-endian machines, we must arrange the bytes in the right
118 * order. (This also works on machines of unknown byte order.)
119 */
120 md5_word_t X[16];
121 const md5_byte_t *xp = data;
122 int i;
123
124 for (i = 0; i < 16; ++i, xp += 4)
125 X[i] = xp[0] + (xp[1] << 8) + (xp[2] << 16) + (xp[3] << 24);
126
127 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
128
129 /* Round 1. */
130 /* Let [abcd k s i] denote the operation
131 a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
132 #define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
133 #define SET(a, b, c, d, k, s, Ti)\
134 t = a + F(b,c,d) + X[k] + Ti;\
135 a = ROTATE_LEFT(t, s) + b
136 /* Do the following 16 operations. */
137 SET(a, b, c, d, 0, 7, T1);
138 SET(d, a, b, c, 1, 12, T2);
139 SET(c, d, a, b, 2, 17, T3);
140 SET(b, c, d, a, 3, 22, T4);
141 SET(a, b, c, d, 4, 7, T5);
142 SET(d, a, b, c, 5, 12, T6);
143 SET(c, d, a, b, 6, 17, T7);
144 SET(b, c, d, a, 7, 22, T8);
145 SET(a, b, c, d, 8, 7, T9);
146 SET(d, a, b, c, 9, 12, T10);
147 SET(c, d, a, b, 10, 17, T11);
148 SET(b, c, d, a, 11, 22, T12);
149 SET(a, b, c, d, 12, 7, T13);
150 SET(d, a, b, c, 13, 12, T14);
151 SET(c, d, a, b, 14, 17, T15);
152 SET(b, c, d, a, 15, 22, T16);
153 #undef SET
154
155 /* Round 2. */
156 /* Let [abcd k s i] denote the operation
157 a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */
158 #define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
159 #define SET(a, b, c, d, k, s, Ti)\
160 t = a + G(b,c,d) + X[k] + Ti;\
161 a = ROTATE_LEFT(t, s) + b
162 /* Do the following 16 operations. */
163 SET(a, b, c, d, 1, 5, T17);
164 SET(d, a, b, c, 6, 9, T18);
165 SET(c, d, a, b, 11, 14, T19);
166 SET(b, c, d, a, 0, 20, T20);
167 SET(a, b, c, d, 5, 5, T21);
168 SET(d, a, b, c, 10, 9, T22);
169 SET(c, d, a, b, 15, 14, T23);
170 SET(b, c, d, a, 4, 20, T24);
171 SET(a, b, c, d, 9, 5, T25);
172 SET(d, a, b, c, 14, 9, T26);
173 SET(c, d, a, b, 3, 14, T27);
174 SET(b, c, d, a, 8, 20, T28);
175 SET(a, b, c, d, 13, 5, T29);
176 SET(d, a, b, c, 2, 9, T30);
177 SET(c, d, a, b, 7, 14, T31);
178 SET(b, c, d, a, 12, 20, T32);
179 #undef SET
180
181 /* Round 3. */
182 /* Let [abcd k s t] denote the operation
183 a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */
184 #define H(x, y, z) ((x) ^ (y) ^ (z))
185 #define SET(a, b, c, d, k, s, Ti)\
186 t = a + H(b,c,d) + X[k] + Ti;\
187 a = ROTATE_LEFT(t, s) + b
188 /* Do the following 16 operations. */
189 SET(a, b, c, d, 5, 4, T33);
190 SET(d, a, b, c, 8, 11, T34);
191 SET(c, d, a, b, 11, 16, T35);
192 SET(b, c, d, a, 14, 23, T36);
193 SET(a, b, c, d, 1, 4, T37);
194 SET(d, a, b, c, 4, 11, T38);
195 SET(c, d, a, b, 7, 16, T39);
196 SET(b, c, d, a, 10, 23, T40);
197 SET(a, b, c, d, 13, 4, T41);
198 SET(d, a, b, c, 0, 11, T42);
199 SET(c, d, a, b, 3, 16, T43);
200 SET(b, c, d, a, 6, 23, T44);
201 SET(a, b, c, d, 9, 4, T45);
202 SET(d, a, b, c, 12, 11, T46);
203 SET(c, d, a, b, 15, 16, T47);
204 SET(b, c, d, a, 2, 23, T48);
205 #undef SET
206
207 /* Round 4. */
208 /* Let [abcd k s t] denote the operation
209 a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */
210 #define I(x, y, z) ((y) ^ ((x) | ~(z)))
211 #define SET(a, b, c, d, k, s, Ti)\
212 t = a + I(b,c,d) + X[k] + Ti;\
213 a = ROTATE_LEFT(t, s) + b
214 /* Do the following 16 operations. */
215 SET(a, b, c, d, 0, 6, T49);
216 SET(d, a, b, c, 7, 10, T50);
217 SET(c, d, a, b, 14, 15, T51);
218 SET(b, c, d, a, 5, 21, T52);
219 SET(a, b, c, d, 12, 6, T53);
220 SET(d, a, b, c, 3, 10, T54);
221 SET(c, d, a, b, 10, 15, T55);
222 SET(b, c, d, a, 1, 21, T56);
223 SET(a, b, c, d, 8, 6, T57);
224 SET(d, a, b, c, 15, 10, T58);
225 SET(c, d, a, b, 6, 15, T59);
226 SET(b, c, d, a, 13, 21, T60);
227 SET(a, b, c, d, 4, 6, T61);
228 SET(d, a, b, c, 11, 10, T62);
229 SET(c, d, a, b, 2, 15, T63);
230 SET(b, c, d, a, 9, 21, T64);
231 #undef SET
232
233 /* Then perform the following additions. (That is increment each
234 of the four registers by the value it had before this block
235 was started.) */
236 pms->abcd[0] += a;
237 pms->abcd[1] += b;
238 pms->abcd[2] += c;
239 pms->abcd[3] += d;
240 }
241
242 void
md5_init(md5_state_t * pms)243 md5_init(md5_state_t *pms)
244 {
245 pms->count[0] = pms->count[1] = 0;
246 pms->abcd[0] = 0x67452301;
247 pms->abcd[1] = 0xefcdab89;
248 pms->abcd[2] = 0x98badcfe;
249 pms->abcd[3] = 0x10325476;
250 }
251
252 void
md5_append(md5_state_t * pms,const md5_byte_t * data,int nbytes)253 md5_append(md5_state_t *pms, const md5_byte_t *data, int nbytes)
254 {
255 const md5_byte_t *p = data;
256 int left = nbytes;
257 int offset = (pms->count[0] >> 3) & 63;
258 md5_word_t nbits = (md5_word_t)(nbytes << 3);
259
260 if (nbytes <= 0)
261 return;
262
263 /* Update the message length. */
264 pms->count[1] += nbytes >> 29;
265 pms->count[0] += nbits;
266 if (pms->count[0] < nbits)
267 pms->count[1]++;
268
269 /* Process an initial partial block. */
270 if (offset) {
271 int copy = (offset + nbytes > 64 ? 64 - offset : nbytes);
272
273 memcpy(pms->buf + offset, p, copy);
274 if (offset + copy < 64)
275 return;
276 p += copy;
277 left -= copy;
278 md5_process(pms, pms->buf);
279 }
280
281 /* Process full blocks. */
282 for (; left >= 64; p += 64, left -= 64)
283 md5_process(pms, p);
284
285 /* Process a final partial block. */
286 if (left)
287 memcpy(pms->buf, p, left);
288 }
289
290 void
md5_finish(md5_state_t * pms,md5_byte_t digest[16])291 md5_finish(md5_state_t *pms, md5_byte_t digest[16])
292 {
293 static const md5_byte_t pad[64] = {
294 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
295 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
296 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
297 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
298 };
299 md5_byte_t data[8];
300 int i;
301
302 /* Save the length before padding. */
303 for (i = 0; i < 8; ++i)
304 data[i] = (md5_byte_t)(pms->count[i >> 2] >> ((i & 3) << 3));
305 /* Pad to 56 bytes mod 64. */
306 md5_append(pms, pad, ((55 - (pms->count[0] >> 3)) & 63) + 1);
307 /* Append the length. */
308 md5_append(pms, data, 8);
309 for (i = 0; i < 16; ++i)
310 digest[i] = (md5_byte_t)(pms->abcd[i >> 2] >> ((i & 3) << 3));
311 }
312