md4-internal.c revision 8d520ff1dc2da35cdca849e982051b86468016d8 
1/*
2 * MD4 hash implementation
3 * Copyright (c) 2006, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "crypto.h"
19
20#define	MD4_BLOCK_LENGTH		64
21#define	MD4_DIGEST_LENGTH		16
22
23typedef struct MD4Context {
24	u32 state[4];			/* state */
25	u64 count;			/* number of bits, mod 2^64 */
26	u8 buffer[MD4_BLOCK_LENGTH];	/* input buffer */
27} MD4_CTX;
28
29
30static void MD4Init(MD4_CTX *ctx);
31static void MD4Update(MD4_CTX *ctx, const unsigned char *input, size_t len);
32static void MD4Final(unsigned char digest[MD4_DIGEST_LENGTH], MD4_CTX *ctx);
33
34
35int md4_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
36{
37	MD4_CTX ctx;
38	size_t i;
39
40	MD4Init(&ctx);
41	for (i = 0; i < num_elem; i++)
42		MD4Update(&ctx, addr[i], len[i]);
43	MD4Final(mac, &ctx);
44	return 0;
45}
46
47
48/* ===== start - public domain MD4 implementation ===== */
49/*	$OpenBSD: md4.c,v 1.7 2005/08/08 08:05:35 espie Exp $	*/
50
51/*
52 * This code implements the MD4 message-digest algorithm.
53 * The algorithm is due to Ron Rivest.	This code was
54 * written by Colin Plumb in 1993, no copyright is claimed.
55 * This code is in the public domain; do with it what you wish.
56 * Todd C. Miller modified the MD5 code to do MD4 based on RFC 1186.
57 *
58 * Equivalent code is available from RSA Data Security, Inc.
59 * This code has been tested against that, and is equivalent,
60 * except that you don't need to include two pages of legalese
61 * with every copy.
62 *
63 * To compute the message digest of a chunk of bytes, declare an
64 * MD4Context structure, pass it to MD4Init, call MD4Update as
65 * needed on buffers full of bytes, and then call MD4Final, which
66 * will fill a supplied 16-byte array with the digest.
67 */
68
69#define	MD4_DIGEST_STRING_LENGTH	(MD4_DIGEST_LENGTH * 2 + 1)
70
71
72static void
73MD4Transform(u32 state[4], const u8 block[MD4_BLOCK_LENGTH]);
74
75#define PUT_64BIT_LE(cp, value) do {					\
76	(cp)[7] = (value) >> 56;					\
77	(cp)[6] = (value) >> 48;					\
78	(cp)[5] = (value) >> 40;					\
79	(cp)[4] = (value) >> 32;					\
80	(cp)[3] = (value) >> 24;					\
81	(cp)[2] = (value) >> 16;					\
82	(cp)[1] = (value) >> 8;						\
83	(cp)[0] = (value); } while (0)
84
85#define PUT_32BIT_LE(cp, value) do {					\
86	(cp)[3] = (value) >> 24;					\
87	(cp)[2] = (value) >> 16;					\
88	(cp)[1] = (value) >> 8;						\
89	(cp)[0] = (value); } while (0)
90
91static u8 PADDING[MD4_BLOCK_LENGTH] = {
92	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
93	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
94	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
95};
96
97/*
98 * Start MD4 accumulation.
99 * Set bit count to 0 and buffer to mysterious initialization constants.
100 */
101static void MD4Init(MD4_CTX *ctx)
102{
103	ctx->count = 0;
104	ctx->state[0] = 0x67452301;
105	ctx->state[1] = 0xefcdab89;
106	ctx->state[2] = 0x98badcfe;
107	ctx->state[3] = 0x10325476;
108}
109
110/*
111 * Update context to reflect the concatenation of another buffer full
112 * of bytes.
113 */
114static void MD4Update(MD4_CTX *ctx, const unsigned char *input, size_t len)
115{
116	size_t have, need;
117
118	/* Check how many bytes we already have and how many more we need. */
119	have = (size_t)((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1));
120	need = MD4_BLOCK_LENGTH - have;
121
122	/* Update bitcount */
123	ctx->count += (u64)len << 3;
124
125	if (len >= need) {
126		if (have != 0) {
127			os_memcpy(ctx->buffer + have, input, need);
128			MD4Transform(ctx->state, ctx->buffer);
129			input += need;
130			len -= need;
131			have = 0;
132		}
133
134		/* Process data in MD4_BLOCK_LENGTH-byte chunks. */
135		while (len >= MD4_BLOCK_LENGTH) {
136			MD4Transform(ctx->state, input);
137			input += MD4_BLOCK_LENGTH;
138			len -= MD4_BLOCK_LENGTH;
139		}
140	}
141
142	/* Handle any remaining bytes of data. */
143	if (len != 0)
144		os_memcpy(ctx->buffer + have, input, len);
145}
146
147/*
148 * Pad pad to 64-byte boundary with the bit pattern
149 * 1 0* (64-bit count of bits processed, MSB-first)
150 */
151static void MD4Pad(MD4_CTX *ctx)
152{
153	u8 count[8];
154	size_t padlen;
155
156	/* Convert count to 8 bytes in little endian order. */
157	PUT_64BIT_LE(count, ctx->count);
158
159	/* Pad out to 56 mod 64. */
160	padlen = MD4_BLOCK_LENGTH -
161	    ((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1));
162	if (padlen < 1 + 8)
163		padlen += MD4_BLOCK_LENGTH;
164	MD4Update(ctx, PADDING, padlen - 8);		/* padlen - 8 <= 64 */
165	MD4Update(ctx, count, 8);
166}
167
168/*
169 * Final wrapup--call MD4Pad, fill in digest and zero out ctx.
170 */
171static void MD4Final(unsigned char digest[MD4_DIGEST_LENGTH], MD4_CTX *ctx)
172{
173	int i;
174
175	MD4Pad(ctx);
176	if (digest != NULL) {
177		for (i = 0; i < 4; i++)
178			PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
179		os_memset(ctx, 0, sizeof(*ctx));
180	}
181}
182
183
184/* The three core functions - F1 is optimized somewhat */
185
186/* #define F1(x, y, z) (x & y | ~x & z) */
187#define F1(x, y, z) (z ^ (x & (y ^ z)))
188#define F2(x, y, z) ((x & y) | (x & z) | (y & z))
189#define F3(x, y, z) (x ^ y ^ z)
190
191/* This is the central step in the MD4 algorithm. */
192#define MD4STEP(f, w, x, y, z, data, s) \
193	( w += f(x, y, z) + data,  w = w<<s | w>>(32-s) )
194
195/*
196 * The core of the MD4 algorithm, this alters an existing MD4 hash to
197 * reflect the addition of 16 longwords of new data.  MD4Update blocks
198 * the data and converts bytes into longwords for this routine.
199 */
200static void
201MD4Transform(u32 state[4], const u8 block[MD4_BLOCK_LENGTH])
202{
203	u32 a, b, c, d, in[MD4_BLOCK_LENGTH / 4];
204
205#if BYTE_ORDER == LITTLE_ENDIAN
206	os_memcpy(in, block, sizeof(in));
207#else
208	for (a = 0; a < MD4_BLOCK_LENGTH / 4; a++) {
209		in[a] = (u32)(
210		    (u32)(block[a * 4 + 0]) |
211		    (u32)(block[a * 4 + 1]) <<  8 |
212		    (u32)(block[a * 4 + 2]) << 16 |
213		    (u32)(block[a * 4 + 3]) << 24);
214	}
215#endif
216
217	a = state[0];
218	b = state[1];
219	c = state[2];
220	d = state[3];
221
222	MD4STEP(F1, a, b, c, d, in[ 0],  3);
223	MD4STEP(F1, d, a, b, c, in[ 1],  7);
224	MD4STEP(F1, c, d, a, b, in[ 2], 11);
225	MD4STEP(F1, b, c, d, a, in[ 3], 19);
226	MD4STEP(F1, a, b, c, d, in[ 4],  3);
227	MD4STEP(F1, d, a, b, c, in[ 5],  7);
228	MD4STEP(F1, c, d, a, b, in[ 6], 11);
229	MD4STEP(F1, b, c, d, a, in[ 7], 19);
230	MD4STEP(F1, a, b, c, d, in[ 8],  3);
231	MD4STEP(F1, d, a, b, c, in[ 9],  7);
232	MD4STEP(F1, c, d, a, b, in[10], 11);
233	MD4STEP(F1, b, c, d, a, in[11], 19);
234	MD4STEP(F1, a, b, c, d, in[12],  3);
235	MD4STEP(F1, d, a, b, c, in[13],  7);
236	MD4STEP(F1, c, d, a, b, in[14], 11);
237	MD4STEP(F1, b, c, d, a, in[15], 19);
238
239	MD4STEP(F2, a, b, c, d, in[ 0] + 0x5a827999,  3);
240	MD4STEP(F2, d, a, b, c, in[ 4] + 0x5a827999,  5);
241	MD4STEP(F2, c, d, a, b, in[ 8] + 0x5a827999,  9);
242	MD4STEP(F2, b, c, d, a, in[12] + 0x5a827999, 13);
243	MD4STEP(F2, a, b, c, d, in[ 1] + 0x5a827999,  3);
244	MD4STEP(F2, d, a, b, c, in[ 5] + 0x5a827999,  5);
245	MD4STEP(F2, c, d, a, b, in[ 9] + 0x5a827999,  9);
246	MD4STEP(F2, b, c, d, a, in[13] + 0x5a827999, 13);
247	MD4STEP(F2, a, b, c, d, in[ 2] + 0x5a827999,  3);
248	MD4STEP(F2, d, a, b, c, in[ 6] + 0x5a827999,  5);
249	MD4STEP(F2, c, d, a, b, in[10] + 0x5a827999,  9);
250	MD4STEP(F2, b, c, d, a, in[14] + 0x5a827999, 13);
251	MD4STEP(F2, a, b, c, d, in[ 3] + 0x5a827999,  3);
252	MD4STEP(F2, d, a, b, c, in[ 7] + 0x5a827999,  5);
253	MD4STEP(F2, c, d, a, b, in[11] + 0x5a827999,  9);
254	MD4STEP(F2, b, c, d, a, in[15] + 0x5a827999, 13);
255
256	MD4STEP(F3, a, b, c, d, in[ 0] + 0x6ed9eba1,  3);
257	MD4STEP(F3, d, a, b, c, in[ 8] + 0x6ed9eba1,  9);
258	MD4STEP(F3, c, d, a, b, in[ 4] + 0x6ed9eba1, 11);
259	MD4STEP(F3, b, c, d, a, in[12] + 0x6ed9eba1, 15);
260	MD4STEP(F3, a, b, c, d, in[ 2] + 0x6ed9eba1,  3);
261	MD4STEP(F3, d, a, b, c, in[10] + 0x6ed9eba1,  9);
262	MD4STEP(F3, c, d, a, b, in[ 6] + 0x6ed9eba1, 11);
263	MD4STEP(F3, b, c, d, a, in[14] + 0x6ed9eba1, 15);
264	MD4STEP(F3, a, b, c, d, in[ 1] + 0x6ed9eba1,  3);
265	MD4STEP(F3, d, a, b, c, in[ 9] + 0x6ed9eba1,  9);
266	MD4STEP(F3, c, d, a, b, in[ 5] + 0x6ed9eba1, 11);
267	MD4STEP(F3, b, c, d, a, in[13] + 0x6ed9eba1, 15);
268	MD4STEP(F3, a, b, c, d, in[ 3] + 0x6ed9eba1,  3);
269	MD4STEP(F3, d, a, b, c, in[11] + 0x6ed9eba1,  9);
270	MD4STEP(F3, c, d, a, b, in[ 7] + 0x6ed9eba1, 11);
271	MD4STEP(F3, b, c, d, a, in[15] + 0x6ed9eba1, 15);
272
273	state[0] += a;
274	state[1] += b;
275	state[2] += c;
276	state[3] += d;
277}
278/* ===== end - public domain MD4 implementation ===== */
279