d4dde3693a9a95125d8b0adf18dcd3048bc5831e
[strongswan.git] / src / libstrongswan / crypto / hashers / md5_hasher.c
1 /**
2 * @file md5_hasher.c
3 *
4 * @brief Implementation of md5_hasher_t.
5 *
6 */
7
8 /*
9 * Copyright (C) 2005-2006 Martin Willi
10 * Copyright (C) 2005 Jan Hutter
11 * Hochschule fuer Technik Rapperswil
12 * Copyright (C) 1991-1992, RSA Data Security, Inc. Created 1991.
13 * All rights reserved.
14 *
15 * Derived from the RSA Data Security, Inc. MD5 Message-Digest Algorithm.
16 * Ported to fulfill hasher_t interface.
17 *
18 * This program is free software; you can redistribute it and/or modify it
19 * under the terms of the GNU General Public License as published by the
20 * Free Software Foundation; either version 2 of the License, or (at your
21 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
22 *
23 * This program is distributed in the hope that it will be useful, but
24 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
25 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
26 * for more details.
27 */
28
29 #include <string.h>
30
31 #include "md5_hasher.h"
32
33
34 /* Constants for MD5Transform routine. */
35 #define S11 7
36 #define S12 12
37 #define S13 17
38 #define S14 22
39 #define S21 5
40 #define S22 9
41 #define S23 14
42 #define S24 20
43 #define S31 4
44 #define S32 11
45 #define S33 16
46 #define S34 23
47 #define S41 6
48 #define S42 10
49 #define S43 15
50 #define S44 21
51
52 static u_int8_t PADDING[64] = {
53 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
56 };
57
58 /*
59 * ugly macro stuff
60 */
61 /* F, G, H and I are basic MD5 functions.
62 */
63 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
64 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
65 #define H(x, y, z) ((x) ^ (y) ^ (z))
66 #define I(x, y, z) ((y) ^ ((x) | (~z)))
67
68 /* ROTATE_LEFT rotates x left n bits.
69 */
70 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
71
72 /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
73 Rotation is separate from addition to prevent recomputation.
74 */
75 #define FF(a, b, c, d, x, s, ac) { \
76 (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
77 (a) = ROTATE_LEFT ((a), (s)); \
78 (a) += (b); \
79 }
80 #define GG(a, b, c, d, x, s, ac) { \
81 (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
82 (a) = ROTATE_LEFT ((a), (s)); \
83 (a) += (b); \
84 }
85 #define HH(a, b, c, d, x, s, ac) { \
86 (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
87 (a) = ROTATE_LEFT ((a), (s)); \
88 (a) += (b); \
89 }
90 #define II(a, b, c, d, x, s, ac) { \
91 (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
92 (a) = ROTATE_LEFT ((a), (s)); \
93 (a) += (b); \
94 }
95
96
97
98 typedef struct private_md5_hasher_t private_md5_hasher_t;
99
100 /**
101 * Private data structure with hasing context.
102 */
103 struct private_md5_hasher_t {
104 /**
105 * Public interface for this hasher.
106 */
107 md5_hasher_t public;
108
109 /*
110 * State of the hasher.
111 */
112 u_int32_t state[5];
113 u_int32_t count[2];
114 u_int8_t buffer[64];
115 };
116
117
118 #if BYTE_ORDER != LITTLE_ENDIAN
119
120 /* Encodes input (u_int32_t) into output (u_int8_t). Assumes len is
121 * a multiple of 4.
122 */
123 static void Encode (u_int8_t *output, u_int32_t *input, size_t len)
124 {
125 size_t i, j;
126
127 for (i = 0, j = 0; j < len; i++, j += 4)
128 {
129 output[j] = (u_int8_t)(input[i] & 0xff);
130 output[j+1] = (u_int8_t)((input[i] >> 8) & 0xff);
131 output[j+2] = (u_int8_t)((input[i] >> 16) & 0xff);
132 output[j+3] = (u_int8_t)((input[i] >> 24) & 0xff);
133 }
134 }
135
136 /* Decodes input (u_int8_t) into output (u_int32_t). Assumes len is
137 * a multiple of 4.
138 */
139 static void Decode(u_int32_t *output, u_int8_t *input, size_t len)
140 {
141 size_t i, j;
142
143 for (i = 0, j = 0; j < len; i++, j += 4)
144 {
145 output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
146 (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
147 }
148 }
149
150 #elif BYTE_ORDER == LITTLE_ENDIAN
151 #define Encode memcpy
152 #define Decode memcpy
153 #endif
154
155 /* MD5 basic transformation. Transforms state based on block.
156 */
157 static void MD5Transform(u_int32_t state[4], u_int8_t block[64])
158 {
159 u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
160
161 Decode(x, block, 64);
162
163 /* Round 1 */
164 FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
165 FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
166 FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
167 FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
168 FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
169 FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
170 FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
171 FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
172 FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
173 FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
174 FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
175 FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
176 FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
177 FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
178 FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
179 FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
180
181 /* Round 2 */
182 GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
183 GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
184 GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
185 GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
186 GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
187 GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */
188 GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
189 GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
190 GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
191 GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
192 GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
193 GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
194 GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
195 GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
196 GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
197 GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
198
199 /* Round 3 */
200 HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
201 HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
202 HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
203 HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
204 HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
205 HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
206 HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
207 HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
208 HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
209 HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
210 HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
211 HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
212 HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
213 HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
214 HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
215 HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
216
217 /* Round 4 */
218 II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
219 II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
220 II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
221 II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
222 II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
223 II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
224 II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
225 II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
226 II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
227 II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
228 II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
229 II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
230 II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
231 II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
232 II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
233 II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
234
235 state[0] += a;
236 state[1] += b;
237 state[2] += c;
238 state[3] += d;
239 }
240
241 /* MD5 block update operation. Continues an MD5 message-digest
242 * operation, processing another message block, and updating the
243 * context.
244 */
245 static void MD5Update(private_md5_hasher_t *this, u_int8_t *input, size_t inputLen)
246 {
247 u_int32_t i;
248 size_t index, partLen;
249
250 /* Compute number of bytes mod 64 */
251 index = (u_int8_t)((this->count[0] >> 3) & 0x3F);
252
253 /* Update number of bits */
254 if ((this->count[0] += (inputLen << 3)) < (inputLen << 3))
255 {
256 this->count[1]++;
257 }
258 this->count[1] += (inputLen >> 29);
259
260 partLen = 64 - index;
261
262 /* Transform as many times as possible. */
263 if (inputLen >= partLen)
264 {
265 memcpy(&this->buffer[index], input, partLen);
266 MD5Transform (this->state, this->buffer);
267
268 for (i = partLen; i + 63 < inputLen; i += 64)
269 {
270 MD5Transform (this->state, &input[i]);
271 }
272 index = 0;
273 }
274 else
275 {
276 i = 0;
277 }
278
279 /* Buffer remaining input */
280 memcpy(&this->buffer[index], &input[i], inputLen-i);
281 }
282
283 /* MD5 finalization. Ends an MD5 message-digest operation, writing the
284 * the message digest and zeroizing the context.
285 */
286 static void MD5Final (private_md5_hasher_t *this, u_int8_t digest[16])
287 {
288 u_int8_t bits[8];
289 size_t index, padLen;
290
291 /* Save number of bits */
292 Encode (bits, this->count, 8);
293
294 /* Pad out to 56 mod 64. */
295 index = (size_t)((this->count[0] >> 3) & 0x3f);
296 padLen = (index < 56) ? (56 - index) : (120 - index);
297 MD5Update (this, PADDING, padLen);
298
299 /* Append length (before padding) */
300 MD5Update (this, bits, 8);
301
302 if (digest != NULL) /* Bill Simpson's padding */
303 {
304 /* store state in digest */
305 Encode (digest, this->state, 16);
306 }
307 }
308
309
310
311 /**
312 * Implementation of hasher_t.get_hash.
313 */
314 static void get_hash(private_md5_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
315 {
316 MD5Update(this, chunk.ptr, chunk.len);
317 if (buffer != NULL)
318 {
319 MD5Final(this, buffer);
320 this->public.hasher_interface.reset(&(this->public.hasher_interface));
321 }
322 }
323
324
325 /**
326 * Implementation of hasher_t.allocate_hash.
327 */
328 static void allocate_hash(private_md5_hasher_t *this, chunk_t chunk, chunk_t *hash)
329 {
330 chunk_t allocated_hash;
331
332 MD5Update(this, chunk.ptr, chunk.len);
333 if (hash != NULL)
334 {
335 allocated_hash.ptr = malloc(HASH_SIZE_MD5);
336 allocated_hash.len = HASH_SIZE_MD5;
337
338 MD5Final(this, allocated_hash.ptr);
339 this->public.hasher_interface.reset(&(this->public.hasher_interface));
340
341 *hash = allocated_hash;
342 }
343 }
344
345 /**
346 * Implementation of hasher_t.get_hash_size.
347 */
348 static size_t get_hash_size(private_md5_hasher_t *this)
349 {
350 return HASH_SIZE_MD5;
351 }
352
353 /**
354 * Implementation of hasher_t.reset.
355 */
356 static void reset(private_md5_hasher_t *this)
357 {
358 this->state[0] = 0x67452301;
359 this->state[1] = 0xefcdab89;
360 this->state[2] = 0x98badcfe;
361 this->state[3] = 0x10325476;
362 this->count[0] = 0;
363 this->count[1] = 0;
364 }
365
366 /**
367 * Implementation of hasher_t.get_state
368 */
369 static chunk_t get_state(private_md5_hasher_t *this)
370 {
371 chunk_t chunk;
372
373 chunk.ptr = (u_char*)&this->state[0];
374 chunk.len = sizeof(this->state);
375
376 return chunk;
377 }
378
379 /**
380 * Implementation of hasher_t.destroy.
381 */
382 static void destroy(private_md5_hasher_t *this)
383 {
384 free(this);
385 }
386
387 /*
388 * Described in header.
389 */
390 md5_hasher_t *md5_hasher_create(void)
391 {
392 private_md5_hasher_t *this = malloc_thing(private_md5_hasher_t);
393
394 this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
395 this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
396 this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
397 this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
398 this->public.hasher_interface.get_state = (chunk_t (*) (hasher_t*))get_state;
399 this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
400
401 /* initialize */
402 reset(this);
403
404 return &(this->public);
405 }