xref: /minix/common/lib/libc/md/md4c.c (revision ebfedea0)
1 /*	$NetBSD: md4c.c,v 1.5 2012/03/20 16:21:41 matt Exp $	*/
2 
3 /*
4  * This file is derived from the RSA Data Security, Inc. MD4 Message-Digest
5  * Algorithm and has been modified by Jason R. Thorpe <thorpej@NetBSD.org>
6  * for portability and formatting.
7  */
8 
9 /*
10  * Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
11  *
12  * License to copy and use this software is granted provided that it
13  * is identified as the "RSA Data Security, Inc. MD4 Message-Digest
14  * Algorithm" in all material mentioning or referencing this software
15  * or this function.
16  *
17  * License is also granted to make and use derivative works provided
18  * that such works are identified as "derived from the RSA Data
19  * Security, Inc. MD4 Message-Digest Algorithm" in all material
20  * mentioning or referencing the derived work.
21  *
22  * RSA Data Security, Inc. makes no representations concerning either
23  * the merchantability of this software or the suitability of this
24  * software for any particular purpose. It is provided "as is"
25  * without express or implied warranty of any kind.
26  *
27  * These notices must be retained in any copies of any part of this
28  * documentation and/or software.
29  */
30 
31 #if !defined(_KERNEL) && !defined(_STANDALONE)
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 __RCSID("$NetBSD: md4c.c,v 1.5 2012/03/20 16:21:41 matt Exp $");
35 #endif /* LIBC_SCCS and not lint */
36 
37 #include "namespace.h"
38 
39 #include <sys/types.h>
40 
41 #include <assert.h>
42 #include <md4.h>
43 #include <string.h>
44 
45 #if HAVE_NBTOOL_CONFIG_H
46 #include "nbtool_config.h"
47 #endif
48 
49 #else
50 
51 #include <sys/param.h>
52 #include <sys/md4.h>
53 #include <lib/libkern/libkern.h>
54 
55 #endif /* !_KERNEL && !_STANDALONE */
56 
57 #if !HAVE_MD4_H
58 
59 typedef unsigned char *POINTER;
60 typedef uint16_t UINT2;
61 typedef uint32_t UINT4;
62 
63 /*
64  * Constants for MD4Transform routine.
65  */
66 #define S11 3
67 #define S12 7
68 #define S13 11
69 #define S14 19
70 #define S21 3
71 #define S22 5
72 #define S23 9
73 #define S24 13
74 #define S31 3
75 #define S32 9
76 #define S33 11
77 #define S34 15
78 
79 static void MD4Transform(UINT4 [4], const unsigned char [64]);
80 
81 static void Encode(unsigned char *, UINT4 *, unsigned int);
82 static void Decode(UINT4 *, const unsigned char *, unsigned int);
83 
84 static const unsigned char PADDING[64] = {
85 	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
86 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
87 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
88 };
89 
90 /*
91  * F, G and H are basic MD4 functions.
92  */
93 #define F(x, y, z)	(((x) & (y)) | ((~x) & (z)))
94 #define G(x, y, z)	(((x) & (y)) | ((x) & (z)) | ((y) & (z)))
95 #define H(x, y, z)	((x) ^ (y) ^ (z))
96 
97 /*
98  * ROTATE_LEFT rotates x left n bits.
99  */
100 #define ROTATE_LEFT(x, n)	(((x) << (n)) | ((x) >> (32-(n))))
101 
102 /*
103  * FF, GG and HH are transformations for rounds 1, 2 and 3.
104  * Rotation is separate from addition to prevent recomputation.
105  */
106 #define FF(a, b, c, d, x, s) { \
107 	(a) += F ((b), (c), (d)) + (x); \
108 	(a) = ROTATE_LEFT ((a), (s)); \
109 }
110 
111 #define GG(a, b, c, d, x, s) { \
112 	(a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
113 	(a) = ROTATE_LEFT ((a), (s)); \
114 }
115 
116 #define HH(a, b, c, d, x, s) { \
117 	(a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
118 	(a) = ROTATE_LEFT ((a), (s)); \
119 }
120 
121 #if !defined(_KERNEL) && !defined(_STANDALONE) && defined(__weak_alias)
122 __weak_alias(MD4Init,_MD4Init)
123 __weak_alias(MD4Update,_MD4Update)
124 __weak_alias(MD4Final,_MD4Final)
125 __weak_alias(MD4Transform,_MD4Transform)
126 #endif
127 
128 /*
129  * MD4 initialization. Begins an MD4 operation, writing a new context.
130  */
131 void
132 MD4Init(MD4_CTX *context)		/* context */
133 {
134 
135 	_DIAGASSERT(context != 0);
136 
137 	context->count[0] = context->count[1] = 0;
138 
139 	/* Load magic initialization constants. */
140 	context->state[0] = 0x67452301;
141 	context->state[1] = 0xefcdab89;
142 	context->state[2] = 0x98badcfe;
143 	context->state[3] = 0x10325476;
144 }
145 
146 /*
147  * MD4 block update operation.  Continues an MD4 message-digest
148  * operation, processing another message block, and updating the
149  * context.
150  */
151 void
152 MD4Update (MD4_CTX *context,		/* context */
153 	const unsigned char *input,	/* input block */
154 	unsigned int inputLen)		/* length of input block */
155 {
156 	unsigned int i, idx, partLen;
157 
158 	_DIAGASSERT(context != 0);
159 	_DIAGASSERT(input != 0);
160 
161 	/* Compute number of bytes mod 64 */
162 	idx = (unsigned int)((context->count[0] >> 3) & 0x3F);
163 
164 	/* Update number of bits */
165 	if ((context->count[0] += ((UINT4)inputLen << 3))
166 	    < ((UINT4)inputLen << 3))
167 		context->count[1]++;
168 	context->count[1] += ((UINT4)inputLen >> 29);
169 
170 	partLen = 64 - idx;
171 
172 	/* Transform as many times as possible. */
173 	if (inputLen >= partLen) {
174 		memcpy(&context->buffer[idx], input, partLen);
175 		MD4Transform(context->state, context->buffer);
176 
177 		for (i = partLen; i + 63 < inputLen; i += 64)
178 			MD4Transform(context->state, &input[i]);
179 
180 		idx = 0;
181 	} else
182 		i = 0;
183 
184 	/* Buffer remaining input */
185 	memcpy(&context->buffer[idx], &input[i], inputLen - i);
186 }
187 
188 /*
189  * MD4 finalization.  Ends an MD4 message-digest operation, writing the
190  * message digest and zeroing the context.
191  */
192 void
193 MD4Final (unsigned char digest[16],	/* message digest */
194 	MD4_CTX *context)		/* context */
195 {
196 	unsigned char bits[8];
197 	unsigned int idx, padLen;
198 
199 	_DIAGASSERT(digest != 0);
200 	_DIAGASSERT(context != 0);
201 
202 	/* Save number of bits */
203 	Encode(bits, context->count, 8);
204 
205 	/* Pad out to 56 mod 64. */
206 	idx = (unsigned int)((context->count[0] >> 3) & 0x3f);
207 	padLen = (idx < 56) ? (56 - idx) : (120 - idx);
208 	MD4Update(context, PADDING, padLen);
209 
210 	/* Append length (before padding) */
211 	MD4Update(context, bits, 8);
212 
213 	/* Store state in digest */
214 	Encode(digest, context->state, 16);
215 
216 	/* Zeroize sensitive information. */
217 	memset(context, 0, sizeof(*context));
218 }
219 
220 /*
221  * MD4 basic transformation.  Transforms state based on block.
222  */
223 static void
224 MD4Transform (UINT4 state[4], const unsigned char block[64])
225 {
226 	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
227 
228 	Decode(x, block, 64);
229 
230 	/* Round 1 */
231 	FF (a, b, c, d, x[ 0], S11); /* 1 */
232 	FF (d, a, b, c, x[ 1], S12); /* 2 */
233 	FF (c, d, a, b, x[ 2], S13); /* 3 */
234 	FF (b, c, d, a, x[ 3], S14); /* 4 */
235 	FF (a, b, c, d, x[ 4], S11); /* 5 */
236 	FF (d, a, b, c, x[ 5], S12); /* 6 */
237 	FF (c, d, a, b, x[ 6], S13); /* 7 */
238 	FF (b, c, d, a, x[ 7], S14); /* 8 */
239 	FF (a, b, c, d, x[ 8], S11); /* 9 */
240 	FF (d, a, b, c, x[ 9], S12); /* 10 */
241 	FF (c, d, a, b, x[10], S13); /* 11 */
242 	FF (b, c, d, a, x[11], S14); /* 12 */
243 	FF (a, b, c, d, x[12], S11); /* 13 */
244 	FF (d, a, b, c, x[13], S12); /* 14 */
245 	FF (c, d, a, b, x[14], S13); /* 15 */
246 	FF (b, c, d, a, x[15], S14); /* 16 */
247 
248 	/* Round 2 */
249 	GG (a, b, c, d, x[ 0], S21); /* 17 */
250 	GG (d, a, b, c, x[ 4], S22); /* 18 */
251 	GG (c, d, a, b, x[ 8], S23); /* 19 */
252 	GG (b, c, d, a, x[12], S24); /* 20 */
253 	GG (a, b, c, d, x[ 1], S21); /* 21 */
254 	GG (d, a, b, c, x[ 5], S22); /* 22 */
255 	GG (c, d, a, b, x[ 9], S23); /* 23 */
256 	GG (b, c, d, a, x[13], S24); /* 24 */
257 	GG (a, b, c, d, x[ 2], S21); /* 25 */
258 	GG (d, a, b, c, x[ 6], S22); /* 26 */
259 	GG (c, d, a, b, x[10], S23); /* 27 */
260 	GG (b, c, d, a, x[14], S24); /* 28 */
261 	GG (a, b, c, d, x[ 3], S21); /* 29 */
262 	GG (d, a, b, c, x[ 7], S22); /* 30 */
263 	GG (c, d, a, b, x[11], S23); /* 31 */
264 	GG (b, c, d, a, x[15], S24); /* 32 */
265 
266 	/* Round 3 */
267 	HH (a, b, c, d, x[ 0], S31); /* 33 */
268 	HH (d, a, b, c, x[ 8], S32); /* 34 */
269 	HH (c, d, a, b, x[ 4], S33); /* 35 */
270 	HH (b, c, d, a, x[12], S34); /* 36 */
271 	HH (a, b, c, d, x[ 2], S31); /* 37 */
272 	HH (d, a, b, c, x[10], S32); /* 38 */
273 	HH (c, d, a, b, x[ 6], S33); /* 39 */
274 	HH (b, c, d, a, x[14], S34); /* 40 */
275 	HH (a, b, c, d, x[ 1], S31); /* 41 */
276 	HH (d, a, b, c, x[ 9], S32); /* 42 */
277 	HH (c, d, a, b, x[ 5], S33); /* 43 */
278 	HH (b, c, d, a, x[13], S34); /* 44 */
279 	HH (a, b, c, d, x[ 3], S31); /* 45 */
280 	HH (d, a, b, c, x[11], S32); /* 46 */
281 	HH (c, d, a, b, x[ 7], S33); /* 47 */
282 	HH (b, c, d, a, x[15], S34); /* 48 */
283 
284 	state[0] += a;
285 	state[1] += b;
286 	state[2] += c;
287 	state[3] += d;
288 
289 	/* Zeroize sensitive information. */
290 	memset(x, 0, sizeof (x));
291 }
292 
293 /*
294  * Encodes input (UINT4) into output (unsigned char). Assumes len is
295  * a multiple of 4.
296  */
297 static void
298 Encode(unsigned char *output, UINT4 *input, unsigned int len)
299 {
300 	unsigned int i, j;
301 
302 	for (i = 0, j = 0; j < len; i++, j += 4) {
303 		output[j] = (unsigned char)(input[i] & 0xff);
304 		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
305 		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
306 		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
307 	}
308 }
309 
310 /*
311  * Decodes input (unsigned char) into output (UINT4). Assumes len is
312  * a multiple of 4.
313  */
314 static void
315 Decode(UINT4 *output, const unsigned char *input, unsigned int len)
316 {
317 	unsigned int i, j;
318 
319 	for (i = 0, j = 0; j < len; i++, j += 4)
320 		output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
321 		    (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
322 }
323 
324 #endif /* HAVE_MD4_H */
325