Add a return value to hasher_t.get_hash()
[strongswan.git] / src / libstrongswan / plugins / md4 / md4_hasher.c
1 /*
2 * Copyright (C) 2005-2006 Martin Willi
3 * Copyright (C) 2005 Jan Hutter
4 * Hochschule fuer Technik Rapperswil
5 * Copyright (C) 1990-1992, RSA Data Security, Inc. Created 1990.
6 * All rights reserved.
7 *
8 * Derived from the RSA Data Security, Inc. MD4 Message-Digest Algorithm.
9 * Ported to fulfill hasher_t interface.
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
18 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 * for more details.
20 */
21
22 #include <string.h>
23
24 #include "md4_hasher.h"
25
26 /*
27 * Constants for MD4Transform routine.
28 */
29 #define S11 3
30 #define S12 7
31 #define S13 11
32 #define S14 19
33 #define S21 3
34 #define S22 5
35 #define S23 9
36 #define S24 13
37 #define S31 3
38 #define S32 9
39 #define S33 11
40 #define S34 15
41
42 static u_int8_t PADDING[64] = {
43 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
44 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
45 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
46 };
47
48 /*
49 * F, G, H and I are basic MD4 functions.
50 */
51 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
52 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
53 #define H(x, y, z) ((x) ^ (y) ^ (z))
54
55 /*
56 * ROTATE_LEFT rotates x left n bits.
57 */
58 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
59
60 /* FF, GG and HH are transformations for rounds 1, 2 and 3
61 * Rotation is separate from addition to prevent recomputation
62 */
63 #define FF(a, b, c, d, x, s) { \
64 (a) += F ((b), (c), (d)) + (x); \
65 (a) = ROTATE_LEFT ((a), (s)); \
66 }
67 #define GG(a, b, c, d, x, s) { \
68 (a) += G ((b), (c), (d)) + (x) + (u_int32_t)0x5a827999; \
69 (a) = ROTATE_LEFT ((a), (s)); \
70 }
71 #define HH(a, b, c, d, x, s) { \
72 (a) += H ((b), (c), (d)) + (x) + (u_int32_t)0x6ed9eba1; \
73 (a) = ROTATE_LEFT ((a), (s)); \
74 }
75
76 typedef struct private_md4_hasher_t private_md4_hasher_t;
77
78 /**
79 * Private data structure with hasing context.
80 */
81 struct private_md4_hasher_t {
82 /**
83 * Public interface for this hasher.
84 */
85 md4_hasher_t public;
86
87 /*
88 * State of the hasher.
89 */
90 u_int32_t state[4];
91 u_int32_t count[2];
92 u_int8_t buffer[64];
93 };
94
95 #if BYTE_ORDER != LITTLE_ENDIAN
96
97 /* Encodes input (u_int32_t) into output (u_int8_t). Assumes len is
98 * a multiple of 4.
99 */
100 static void Encode (u_int8_t *output, u_int32_t *input, size_t len)
101 {
102 size_t i, j;
103
104 for (i = 0, j = 0; j < len; i++, j += 4)
105 {
106 output[j] = (u_int8_t)(input[i] & 0xff);
107 output[j+1] = (u_int8_t)((input[i] >> 8) & 0xff);
108 output[j+2] = (u_int8_t)((input[i] >> 16) & 0xff);
109 output[j+3] = (u_int8_t)((input[i] >> 24) & 0xff);
110 }
111 }
112
113 /* Decodes input (u_int8_t) into output (u_int32_t). Assumes len is
114 * a multiple of 4.
115 */
116 static void Decode(u_int32_t *output, u_int8_t *input, size_t len)
117 {
118 size_t i, j;
119
120 for (i = 0, j = 0; j < len; i++, j += 4)
121 {
122 output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
123 (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
124 }
125 }
126
127 #elif BYTE_ORDER == LITTLE_ENDIAN
128 #define Encode memcpy
129 #define Decode memcpy
130 #endif
131
132 /*
133 * MD4 basic transformation. Transforms state based on block.
134 */
135 static void MD4Transform(u_int32_t state[4], u_int8_t block[64])
136 {
137 u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
138
139 Decode(x, block, 64);
140
141 /* Round 1 */
142 FF (a, b, c, d, x[ 0], S11); /* 1 */
143 FF (d, a, b, c, x[ 1], S12); /* 2 */
144 FF (c, d, a, b, x[ 2], S13); /* 3 */
145 FF (b, c, d, a, x[ 3], S14); /* 4 */
146 FF (a, b, c, d, x[ 4], S11); /* 5 */
147 FF (d, a, b, c, x[ 5], S12); /* 6 */
148 FF (c, d, a, b, x[ 6], S13); /* 7 */
149 FF (b, c, d, a, x[ 7], S14); /* 8 */
150 FF (a, b, c, d, x[ 8], S11); /* 9 */
151 FF (d, a, b, c, x[ 9], S12); /* 10 */
152 FF (c, d, a, b, x[10], S13); /* 11 */
153 FF (b, c, d, a, x[11], S14); /* 12 */
154 FF (a, b, c, d, x[12], S11); /* 13 */
155 FF (d, a, b, c, x[13], S12); /* 14 */
156 FF (c, d, a, b, x[14], S13); /* 15 */
157 FF (b, c, d, a, x[15], S14); /* 16 */
158
159 /* Round 2 */
160 GG (a, b, c, d, x[ 0], S21); /* 17 */
161 GG (d, a, b, c, x[ 4], S22); /* 18 */
162 GG (c, d, a, b, x[ 8], S23); /* 19 */
163 GG (b, c, d, a, x[12], S24); /* 20 */
164 GG (a, b, c, d, x[ 1], S21); /* 21 */
165 GG (d, a, b, c, x[ 5], S22); /* 22 */
166 GG (c, d, a, b, x[ 9], S23); /* 23 */
167 GG (b, c, d, a, x[13], S24); /* 24 */
168 GG (a, b, c, d, x[ 2], S21); /* 25 */
169 GG (d, a, b, c, x[ 6], S22); /* 26 */
170 GG (c, d, a, b, x[10], S23); /* 27 */
171 GG (b, c, d, a, x[14], S24); /* 28 */
172 GG (a, b, c, d, x[ 3], S21); /* 29 */
173 GG (d, a, b, c, x[ 7], S22); /* 30 */
174 GG (c, d, a, b, x[11], S23); /* 31 */
175 GG (b, c, d, a, x[15], S24); /* 32 */
176
177 /* Round 3 */
178 HH (a, b, c, d, x[ 0], S31); /* 33 */
179 HH (d, a, b, c, x[ 8], S32); /* 34 */
180 HH (c, d, a, b, x[ 4], S33); /* 35 */
181 HH (b, c, d, a, x[12], S34); /* 36 */
182 HH (a, b, c, d, x[ 2], S31); /* 37 */
183 HH (d, a, b, c, x[10], S32); /* 38 */
184 HH (c, d, a, b, x[ 6], S33); /* 39 */
185 HH (b, c, d, a, x[14], S34); /* 40 */
186 HH (a, b, c, d, x[ 1], S31); /* 41 */
187 HH (d, a, b, c, x[ 9], S32); /* 42 */
188 HH (c, d, a, b, x[ 5], S33); /* 43 */
189 HH (b, c, d, a, x[13], S34); /* 44 */
190 HH (a, b, c, d, x[ 3], S31); /* 45 */
191 HH (d, a, b, c, x[11], S32); /* 46 */
192 HH (c, d, a, b, x[ 7], S33); /* 47 */
193 HH (b, c, d, a, x[15], S34); /* 48 */
194
195 state[0] += a;
196 state[1] += b;
197 state[2] += c;
198 state[3] += d;
199 }
200
201 /* MD4 block update operation. Continues an MD4 message-digest
202 * operation, processing another message block, and updating the
203 * context.
204 */
205 static void MD4Update(private_md4_hasher_t *this, u_int8_t *input, size_t inputLen)
206 {
207 u_int32_t i;
208 size_t index, partLen;
209
210 /* Compute number of bytes mod 64 */
211 index = (u_int8_t)((this->count[0] >> 3) & 0x3F);
212
213 /* Update number of bits */
214 if ((this->count[0] += (inputLen << 3)) < (inputLen << 3))
215 {
216 this->count[1]++;
217 }
218 this->count[1] += (inputLen >> 29);
219
220 partLen = 64 - index;
221
222 /* Transform as many times as possible. */
223 if (inputLen >= partLen)
224 {
225 memcpy(&this->buffer[index], input, partLen);
226 MD4Transform (this->state, this->buffer);
227
228 for (i = partLen; i + 63 < inputLen; i += 64)
229 {
230 MD4Transform (this->state, &input[i]);
231 }
232 index = 0;
233 }
234 else
235 {
236 i = 0;
237 }
238
239 /* Buffer remaining input */
240 memcpy(&this->buffer[index], &input[i], inputLen-i);
241 }
242
243 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
244 * the message digest and zeroizing the context.
245 */
246 static void MD4Final (private_md4_hasher_t *this, u_int8_t digest[16])
247 {
248 u_int8_t bits[8];
249 size_t index, padLen;
250
251 /* Save number of bits */
252 Encode (bits, this->count, 8);
253
254 /* Pad out to 56 mod 64. */
255 index = (size_t)((this->count[0] >> 3) & 0x3f);
256 padLen = (index < 56) ? (56 - index) : (120 - index);
257 MD4Update (this, PADDING, padLen);
258
259 /* Append length (before padding) */
260 MD4Update (this, bits, 8);
261
262 if (digest != NULL) /* Bill Simpson's padding */
263 {
264 /* store state in digest */
265 Encode (digest, this->state, 16);
266 }
267 }
268
269
270
271 METHOD(hasher_t, get_hash, bool,
272 private_md4_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
273 {
274 MD4Update(this, chunk.ptr, chunk.len);
275 if (buffer != NULL)
276 {
277 MD4Final(this, buffer);
278 this->public.hasher_interface.reset(&(this->public.hasher_interface));
279 }
280 return TRUE;
281 }
282
283 METHOD(hasher_t, allocate_hash, void,
284 private_md4_hasher_t *this, chunk_t chunk, chunk_t *hash)
285 {
286 chunk_t allocated_hash;
287
288 MD4Update(this, chunk.ptr, chunk.len);
289 if (hash != NULL)
290 {
291 allocated_hash.ptr = malloc(HASH_SIZE_MD4);
292 allocated_hash.len = HASH_SIZE_MD4;
293
294 MD4Final(this, allocated_hash.ptr);
295 this->public.hasher_interface.reset(&(this->public.hasher_interface));
296
297 *hash = allocated_hash;
298 }
299 }
300
301 METHOD(hasher_t, get_hash_size, size_t,
302 private_md4_hasher_t *this)
303 {
304 return HASH_SIZE_MD4;
305 }
306
307 METHOD(hasher_t, reset, void,
308 private_md4_hasher_t *this)
309 {
310 this->state[0] = 0x67452301;
311 this->state[1] = 0xefcdab89;
312 this->state[2] = 0x98badcfe;
313 this->state[3] = 0x10325476;
314 this->count[0] = 0;
315 this->count[1] = 0;
316 }
317
318 METHOD(hasher_t, destroy, void,
319 private_md4_hasher_t *this)
320 {
321 free(this);
322 }
323
324 /*
325 * Described in header.
326 */
327 md4_hasher_t *md4_hasher_create(hash_algorithm_t algo)
328 {
329 private_md4_hasher_t *this;
330
331 if (algo != HASH_MD4)
332 {
333 return NULL;
334 }
335
336 INIT(this,
337 .public = {
338 .hasher_interface = {
339 .get_hash = _get_hash,
340 .allocate_hash = _allocate_hash,
341 .get_hash_size = _get_hash_size,
342 .reset = _reset,
343 .destroy = _destroy,
344 },
345 },
346 );
347
348 /* initialize */
349 reset(this);
350
351 return &(this->public);
352 }