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bfa4b218 | 1 | /** |
b2410480 | 2 | * @file md5_hasher.c |
bfa4b218 | 3 | * |
b2410480 | 4 | * @brief Implementation of md5_hasher_t. |
bfa4b218 MW |
5 | * |
6 | */ | |
7 | ||
8 | /* | |
9 | * Copyright (C) 2005 Jan Hutter, Martin Willi | |
10 | * Hochschule fuer Technik Rapperswil | |
11 | * Copyright (C) 1991-1992, RSA Data Security, Inc. Created 1991. | |
12 | * All rights reserved. | |
13 | * | |
14 | * Derived from the RSA Data Security, Inc. MD5 Message-Digest Algorithm. | |
15 | * Ported to fulfill hasher_t interface. | |
16 | * | |
17 | * This program is free software; you can redistribute it and/or modify it | |
18 | * under the terms of the GNU General Public License as published by the | |
19 | * Free Software Foundation; either version 2 of the License, or (at your | |
20 | * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. | |
21 | * | |
22 | * This program is distributed in the hope that it will be useful, but | |
23 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
24 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
25 | * for more details. | |
26 | */ | |
27 | ||
5113680f MW |
28 | #include <string.h> |
29 | ||
b2410480 | 30 | #include "md5_hasher.h" |
bfa4b218 | 31 | |
021c2322 | 32 | #include <definitions.h> |
bfa4b218 MW |
33 | |
34 | #define BLOCK_SIZE_MD5 16 | |
35 | ||
36 | ||
37 | /* Constants for MD5Transform routine. */ | |
38 | #define S11 7 | |
39 | #define S12 12 | |
40 | #define S13 17 | |
41 | #define S14 22 | |
42 | #define S21 5 | |
43 | #define S22 9 | |
44 | #define S23 14 | |
45 | #define S24 20 | |
46 | #define S31 4 | |
47 | #define S32 11 | |
48 | #define S33 16 | |
49 | #define S34 23 | |
50 | #define S41 6 | |
51 | #define S42 10 | |
52 | #define S43 15 | |
53 | #define S44 21 | |
54 | ||
55 | static u_int8_t PADDING[64] = { | |
56 | 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
57 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | |
58 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 | |
59 | }; | |
60 | ||
61 | /* | |
62 | * ugly macro stuff | |
63 | */ | |
64 | /* F, G, H and I are basic MD5 functions. | |
65 | */ | |
66 | #define F(x, y, z) (((x) & (y)) | ((~x) & (z))) | |
67 | #define G(x, y, z) (((x) & (z)) | ((y) & (~z))) | |
68 | #define H(x, y, z) ((x) ^ (y) ^ (z)) | |
69 | #define I(x, y, z) ((y) ^ ((x) | (~z))) | |
70 | ||
71 | /* ROTATE_LEFT rotates x left n bits. | |
72 | */ | |
73 | #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n)))) | |
74 | ||
75 | /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. | |
76 | Rotation is separate from addition to prevent recomputation. | |
77 | */ | |
78 | #define FF(a, b, c, d, x, s, ac) { \ | |
79 | (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \ | |
80 | (a) = ROTATE_LEFT ((a), (s)); \ | |
81 | (a) += (b); \ | |
82 | } | |
83 | #define GG(a, b, c, d, x, s, ac) { \ | |
84 | (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \ | |
85 | (a) = ROTATE_LEFT ((a), (s)); \ | |
86 | (a) += (b); \ | |
87 | } | |
88 | #define HH(a, b, c, d, x, s, ac) { \ | |
89 | (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \ | |
90 | (a) = ROTATE_LEFT ((a), (s)); \ | |
91 | (a) += (b); \ | |
92 | } | |
93 | #define II(a, b, c, d, x, s, ac) { \ | |
94 | (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \ | |
95 | (a) = ROTATE_LEFT ((a), (s)); \ | |
96 | (a) += (b); \ | |
97 | } | |
98 | ||
99 | ||
100 | ||
b2410480 | 101 | typedef struct private_md5_hasher_t private_md5_hasher_t; |
5796aa16 | 102 | |
bfa4b218 | 103 | /** |
6f367178 | 104 | * Private data structure with hasing context. |
bfa4b218 | 105 | */ |
b2410480 | 106 | struct private_md5_hasher_t { |
bfa4b218 | 107 | /** |
6f367178 | 108 | * Public interface for this hasher. |
bfa4b218 | 109 | */ |
b2410480 | 110 | md5_hasher_t public; |
bfa4b218 MW |
111 | |
112 | /* | |
6f367178 | 113 | * State of the hasher. |
bfa4b218 MW |
114 | */ |
115 | u_int32_t state[5]; | |
116 | u_int32_t count[2]; | |
117 | u_int8_t buffer[64]; | |
118 | }; | |
119 | ||
120 | ||
121 | #if BYTE_ORDER != LITTLE_ENDIAN | |
122 | ||
123 | /* Encodes input (u_int32_t) into output (u_int8_t). Assumes len is | |
124 | * a multiple of 4. | |
125 | */ | |
126 | static void Encode (u_int8_t *output, u_int32_t *input, size_t *len) | |
127 | { | |
128 | size_t i, j; | |
129 | ||
130 | for (i = 0, j = 0; j < len; i++, j += 4) | |
131 | { | |
132 | output[j] = (u_int8_t)(input[i] & 0xff); | |
133 | output[j+1] = (u_int8_t)((input[i] >> 8) & 0xff); | |
134 | output[j+2] = (u_int8_t)((input[i] >> 16) & 0xff); | |
135 | output[j+3] = (u_int8_t)((input[i] >> 24) & 0xff); | |
136 | } | |
137 | } | |
138 | ||
139 | /* Decodes input (u_int8_t) into output (u_int32_t). Assumes len is | |
140 | * a multiple of 4. | |
141 | */ | |
142 | static void Decode(u_int32_t *output, u_int8_t *input, size_t len) | |
143 | { | |
144 | size_t i, j; | |
145 | ||
146 | for (i = 0, j = 0; j < len; i++, j += 4) | |
147 | { | |
148 | output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) | | |
149 | (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24); | |
150 | } | |
151 | } | |
152 | ||
153 | #elif BYTE_ORDER == LITTLE_ENDIAN | |
154 | #define Encode memcpy | |
155 | #define Decode memcpy | |
156 | #endif | |
157 | ||
158 | /* MD5 basic transformation. Transforms state based on block. | |
159 | */ | |
160 | static void MD5Transform(u_int32_t state[4], u_int8_t block[64]) | |
161 | { | |
162 | u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16]; | |
163 | ||
164 | Decode(x, block, 64); | |
165 | ||
166 | /* Round 1 */ | |
167 | FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */ | |
168 | FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */ | |
169 | FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */ | |
170 | FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */ | |
171 | FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */ | |
172 | FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */ | |
173 | FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */ | |
174 | FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */ | |
175 | FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */ | |
176 | FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */ | |
177 | FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */ | |
178 | FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */ | |
179 | FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */ | |
180 | FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */ | |
181 | FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */ | |
182 | FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */ | |
183 | ||
184 | /* Round 2 */ | |
185 | GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */ | |
186 | GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */ | |
187 | GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */ | |
188 | GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */ | |
189 | GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */ | |
190 | GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */ | |
191 | GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */ | |
192 | GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */ | |
193 | GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */ | |
194 | GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */ | |
195 | GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */ | |
196 | GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */ | |
197 | GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */ | |
198 | GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */ | |
199 | GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */ | |
200 | GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */ | |
201 | ||
202 | /* Round 3 */ | |
203 | HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */ | |
204 | HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */ | |
205 | HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */ | |
206 | HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */ | |
207 | HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */ | |
208 | HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */ | |
209 | HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */ | |
210 | HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */ | |
211 | HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */ | |
212 | HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */ | |
213 | HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */ | |
214 | HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */ | |
215 | HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */ | |
216 | HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */ | |
217 | HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */ | |
218 | HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */ | |
219 | ||
220 | /* Round 4 */ | |
221 | II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */ | |
222 | II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */ | |
223 | II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */ | |
224 | II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */ | |
225 | II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */ | |
226 | II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */ | |
227 | II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */ | |
228 | II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */ | |
229 | II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */ | |
230 | II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */ | |
231 | II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */ | |
232 | II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */ | |
233 | II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */ | |
234 | II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */ | |
235 | II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */ | |
236 | II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */ | |
237 | ||
238 | state[0] += a; | |
239 | state[1] += b; | |
240 | state[2] += c; | |
241 | state[3] += d; | |
242 | } | |
243 | ||
244 | /* MD5 block update operation. Continues an MD5 message-digest | |
245 | * operation, processing another message block, and updating the | |
246 | * context. | |
247 | */ | |
d048df5c | 248 | static void MD5Update(private_md5_hasher_t *this, u_int8_t *input, size_t inputLen) |
bfa4b218 MW |
249 | { |
250 | u_int32_t i; | |
251 | size_t index, partLen; | |
252 | ||
253 | /* Compute number of bytes mod 64 */ | |
254 | index = (u_int8_t)((this->count[0] >> 3) & 0x3F); | |
255 | ||
256 | /* Update number of bits */ | |
257 | if ((this->count[0] += (inputLen << 3)) < (inputLen << 3)) | |
258 | { | |
259 | this->count[1]++; | |
260 | } | |
261 | this->count[1] += (inputLen >> 29); | |
262 | ||
263 | partLen = 64 - index; | |
264 | ||
265 | /* Transform as many times as possible. */ | |
266 | if (inputLen >= partLen) | |
267 | { | |
268 | memcpy(&this->buffer[index], input, partLen); | |
269 | MD5Transform (this->state, this->buffer); | |
270 | ||
271 | for (i = partLen; i + 63 < inputLen; i += 64) | |
272 | { | |
273 | MD5Transform (this->state, &input[i]); | |
274 | } | |
275 | index = 0; | |
276 | } | |
277 | else | |
278 | { | |
279 | i = 0; | |
280 | } | |
281 | ||
282 | /* Buffer remaining input */ | |
283 | memcpy(&this->buffer[index], &input[i], inputLen-i); | |
284 | } | |
285 | ||
286 | /* MD5 finalization. Ends an MD5 message-digest operation, writing the | |
287 | * the message digest and zeroizing the context. | |
288 | */ | |
d048df5c | 289 | static void MD5Final (private_md5_hasher_t *this, u_int8_t digest[16]) |
bfa4b218 MW |
290 | { |
291 | u_int8_t bits[8]; | |
292 | size_t index, padLen; | |
293 | ||
294 | /* Save number of bits */ | |
295 | Encode (bits, this->count, 8); | |
296 | ||
297 | /* Pad out to 56 mod 64. */ | |
298 | index = (size_t)((this->count[0] >> 3) & 0x3f); | |
299 | padLen = (index < 56) ? (56 - index) : (120 - index); | |
300 | MD5Update (this, PADDING, padLen); | |
301 | ||
302 | /* Append length (before padding) */ | |
303 | MD5Update (this, bits, 8); | |
304 | ||
305 | if (digest != NULL) /* Bill Simpson's padding */ | |
306 | { | |
307 | /* store state in digest */ | |
308 | Encode (digest, this->state, 16); | |
309 | } | |
310 | } | |
311 | ||
312 | ||
313 | ||
314 | /** | |
6f367178 | 315 | * Implementation of hasher_t.get_hash. |
bfa4b218 | 316 | */ |
d048df5c | 317 | static void get_hash(private_md5_hasher_t *this, chunk_t chunk, u_int8_t *buffer) |
bfa4b218 MW |
318 | { |
319 | MD5Update(this, chunk.ptr, chunk.len); | |
320 | if (buffer != NULL) | |
321 | { | |
322 | MD5Final(this, buffer); | |
323 | this->public.hasher_interface.reset(&(this->public.hasher_interface)); | |
324 | } | |
bfa4b218 MW |
325 | } |
326 | ||
327 | ||
328 | /** | |
6f367178 | 329 | * Implementation of hasher_t.allocate_hash. |
bfa4b218 | 330 | */ |
d048df5c | 331 | static void allocate_hash(private_md5_hasher_t *this, chunk_t chunk, chunk_t *hash) |
bfa4b218 MW |
332 | { |
333 | chunk_t allocated_hash; | |
334 | ||
335 | MD5Update(this, chunk.ptr, chunk.len); | |
336 | if (hash != NULL) | |
337 | { | |
5113680f | 338 | allocated_hash.ptr = malloc(BLOCK_SIZE_MD5); |
bfa4b218 | 339 | allocated_hash.len = BLOCK_SIZE_MD5; |
d048df5c | 340 | |
bfa4b218 MW |
341 | MD5Final(this, allocated_hash.ptr); |
342 | this->public.hasher_interface.reset(&(this->public.hasher_interface)); | |
343 | ||
344 | *hash = allocated_hash; | |
345 | } | |
bfa4b218 MW |
346 | } |
347 | ||
348 | /** | |
52923c9a | 349 | * Implementation of hasher_t.get_hash_size. |
bfa4b218 | 350 | */ |
52923c9a | 351 | static size_t get_hash_size(private_md5_hasher_t *this) |
bfa4b218 MW |
352 | { |
353 | return BLOCK_SIZE_MD5; | |
354 | } | |
d048df5c | 355 | |
bfa4b218 | 356 | /** |
6f367178 | 357 | * Implementation of hasher_t.reset. |
bfa4b218 | 358 | */ |
d048df5c | 359 | static void reset(private_md5_hasher_t *this) |
bfa4b218 MW |
360 | { |
361 | this->state[0] = 0x67452301; | |
362 | this->state[1] = 0xefcdab89; | |
363 | this->state[2] = 0x98badcfe; | |
364 | this->state[3] = 0x10325476; | |
365 | this->count[0] = 0; | |
366 | this->count[1] = 0; | |
bfa4b218 | 367 | } |
d048df5c | 368 | |
bfa4b218 | 369 | /** |
6f367178 | 370 | * Implementation of hasher_t.destroy. |
bfa4b218 | 371 | */ |
d048df5c | 372 | static void destroy(private_md5_hasher_t *this) |
bfa4b218 | 373 | { |
5113680f | 374 | free(this); |
bfa4b218 MW |
375 | } |
376 | ||
bfa4b218 | 377 | /* |
6f367178 | 378 | * Described in header. |
bfa4b218 | 379 | */ |
b2410480 | 380 | md5_hasher_t *md5_hasher_create() |
bfa4b218 | 381 | { |
5113680f | 382 | private_md5_hasher_t *this = malloc_thing(private_md5_hasher_t); |
d048df5c MW |
383 | |
384 | this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash; | |
385 | this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash; | |
52923c9a | 386 | this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size; |
d048df5c MW |
387 | this->public.hasher_interface.reset = (void (*) (hasher_t*))reset; |
388 | this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy; | |
bfa4b218 MW |
389 | |
390 | /* initialize */ | |
391 | this->public.hasher_interface.reset(&(this->public.hasher_interface)); | |
392 | ||
393 | return &(this->public); | |
394 | } |