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
21#ifdef INTERNAL_MD4
22
23#define	MD4_BLOCK_LENGTH		64
24#define	MD4_DIGEST_LENGTH		16
25
26typedef struct MD4Context {
27	u32 state[4];			/* state */
28	u64 count;			/* number of bits, mod 2^64 */
29	u8 buffer[MD4_BLOCK_LENGTH];	/* input buffer */
30} MD4_CTX;
31
32
33static void MD4Init(MD4_CTX *ctx);
34static void MD4Update(MD4_CTX *ctx, const unsigned char *input, size_t len);
35static void MD4Final(unsigned char digest[MD4_DIGEST_LENGTH], MD4_CTX *ctx);
36
37
38void md4_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
39{
40	MD4_CTX ctx;
41	size_t i;
42
43	MD4Init(&ctx);
44	for (i = 0; i < num_elem; i++)
45		MD4Update(&ctx, addr[i], len[i]);
46	MD4Final(mac, &ctx);
47}
48
49
50/* ===== start - public domain MD4 implementation ===== */
51/*	$OpenBSD: md4.c,v 1.7 2005/08/08 08:05:35 espie Exp $	*/
52
53/*
54 * This code implements the MD4 message-digest algorithm.
55 * The algorithm is due to Ron Rivest.	This code was
56 * written by Colin Plumb in 1993, no copyright is claimed.
57 * This code is in the public domain; do with it what you wish.
58 * Todd C. Miller modified the MD5 code to do MD4 based on RFC 1186.
59 *
60 * Equivalent code is available from RSA Data Security, Inc.
61 * This code has been tested against that, and is equivalent,
62 * except that you don't need to include two pages of legalese
63 * with every copy.
64 *
65 * To compute the message digest of a chunk of bytes, declare an
66 * MD4Context structure, pass it to MD4Init, call MD4Update as
67 * needed on buffers full of bytes, and then call MD4Final, which
68 * will fill a supplied 16-byte array with the digest.
69 */
70
71#define	MD4_DIGEST_STRING_LENGTH	(MD4_DIGEST_LENGTH * 2 + 1)
72
73
74static void
75MD4Transform(u32 state[4], const u8 block[MD4_BLOCK_LENGTH]);
76
77#define PUT_64BIT_LE(cp, value) do {					\
78	(cp)[7] = (value) >> 56;					\
79	(cp)[6] = (value) >> 48;					\
80	(cp)[5] = (value) >> 40;					\
81	(cp)[4] = (value) >> 32;					\
82	(cp)[3] = (value) >> 24;					\
83	(cp)[2] = (value) >> 16;					\
84	(cp)[1] = (value) >> 8;						\
85	(cp)[0] = (value); } while (0)
86
87#define PUT_32BIT_LE(cp, value) do {					\
88	(cp)[3] = (value) >> 24;					\
89	(cp)[2] = (value) >> 16;					\
90	(cp)[1] = (value) >> 8;						\
91	(cp)[0] = (value); } while (0)
92
93static u8 PADDING[MD4_BLOCK_LENGTH] = {
94	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
95	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
96	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
97};
98
99/*
100 * Start MD4 accumulation.
101 * Set bit count to 0 and buffer to mysterious initialization constants.
102 */
103static void MD4Init(MD4_CTX *ctx)
104{
105	ctx->count = 0;
106	ctx->state[0] = 0x67452301;
107	ctx->state[1] = 0xefcdab89;
108	ctx->state[2] = 0x98badcfe;
109	ctx->state[3] = 0x10325476;
110}
111
112/*
113 * Update context to reflect the concatenation of another buffer full
114 * of bytes.
115 */
116static void MD4Update(MD4_CTX *ctx, const unsigned char *input, size_t len)
117{
118	size_t have, need;
119
120	/* Check how many bytes we already have and how many more we need. */
121	have = (size_t)((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1));
122	need = MD4_BLOCK_LENGTH - have;
123
124	/* Update bitcount */
125	ctx->count += (u64)len << 3;
126
127	if (len >= need) {
128		if (have != 0) {
129			os_memcpy(ctx->buffer + have, input, need);
130			MD4Transform(ctx->state, ctx->buffer);
131			input += need;
132			len -= need;
133			have = 0;
134		}
135
136		/* Process data in MD4_BLOCK_LENGTH-byte chunks. */
137		while (len >= MD4_BLOCK_LENGTH) {
138			MD4Transform(ctx->state, input);
139			input += MD4_BLOCK_LENGTH;
140			len -= MD4_BLOCK_LENGTH;
141		}
142	}
143
144	/* Handle any remaining bytes of data. */
145	if (len != 0)
146		os_memcpy(ctx->buffer + have, input, len);
147}
148
149/*
150 * Pad pad to 64-byte boundary with the bit pattern
151 * 1 0* (64-bit count of bits processed, MSB-first)
152 */
153static void MD4Pad(MD4_CTX *ctx)
154{
155	u8 count[8];
156	size_t padlen;
157
158	/* Convert count to 8 bytes in little endian order. */
159	PUT_64BIT_LE(count, ctx->count);
160
161	/* Pad out to 56 mod 64. */
162	padlen = MD4_BLOCK_LENGTH -
163	    ((ctx->count >> 3) & (MD4_BLOCK_LENGTH - 1));
164	if (padlen < 1 + 8)
165		padlen += MD4_BLOCK_LENGTH;
166	MD4Update(ctx, PADDING, padlen - 8);		/* padlen - 8 <= 64 */
167	MD4Update(ctx, count, 8);
168}
169
170/*
171 * Final wrapup--call MD4Pad, fill in digest and zero out ctx.
172 */
173static void MD4Final(unsigned char digest[MD4_DIGEST_LENGTH], MD4_CTX *ctx)
174{
175	int i;
176
177	MD4Pad(ctx);
178	if (digest != NULL) {
179		for (i = 0; i < 4; i++)
180			PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
181		os_memset(ctx, 0, sizeof(*ctx));
182	}
183}
184
185
186/* The three core functions - F1 is optimized somewhat */
187
188/* #define F1(x, y, z) (x & y | ~x & z) */
189#define F1(x, y, z) (z ^ (x & (y ^ z)))
190#define F2(x, y, z) ((x & y) | (x & z) | (y & z))
191#define F3(x, y, z) (x ^ y ^ z)
192
193/* This is the central step in the MD4 algorithm. */
194#define MD4STEP(f, w, x, y, z, data, s) \
195	( w += f(x, y, z) + data,  w = w<<s | w>>(32-s) )
196
197/*
198 * The core of the MD4 algorithm, this alters an existing MD4 hash to
199 * reflect the addition of 16 longwords of new data.  MD4Update blocks
200 * the data and converts bytes into longwords for this routine.
201 */
202static void
203MD4Transform(u32 state[4], const u8 block[MD4_BLOCK_LENGTH])
204{
205	u32 a, b, c, d, in[MD4_BLOCK_LENGTH / 4];
206
207#if BYTE_ORDER == LITTLE_ENDIAN
208	os_memcpy(in, block, sizeof(in));
209#else
210	for (a = 0; a < MD4_BLOCK_LENGTH / 4; a++) {
211		in[a] = (u32)(
212		    (u32)(block[a * 4 + 0]) |
213		    (u32)(block[a * 4 + 1]) <<  8 |
214		    (u32)(block[a * 4 + 2]) << 16 |
215		    (u32)(block[a * 4 + 3]) << 24);
216	}
217#endif
218
219	a = state[0];
220	b = state[1];
221	c = state[2];
222	d = state[3];
223
224	MD4STEP(F1, a, b, c, d, in[ 0],  3);
225	MD4STEP(F1, d, a, b, c, in[ 1],  7);
226	MD4STEP(F1, c, d, a, b, in[ 2], 11);
227	MD4STEP(F1, b, c, d, a, in[ 3], 19);
228	MD4STEP(F1, a, b, c, d, in[ 4],  3);
229	MD4STEP(F1, d, a, b, c, in[ 5],  7);
230	MD4STEP(F1, c, d, a, b, in[ 6], 11);
231	MD4STEP(F1, b, c, d, a, in[ 7], 19);
232	MD4STEP(F1, a, b, c, d, in[ 8],  3);
233	MD4STEP(F1, d, a, b, c, in[ 9],  7);
234	MD4STEP(F1, c, d, a, b, in[10], 11);
235	MD4STEP(F1, b, c, d, a, in[11], 19);
236	MD4STEP(F1, a, b, c, d, in[12],  3);
237	MD4STEP(F1, d, a, b, c, in[13],  7);
238	MD4STEP(F1, c, d, a, b, in[14], 11);
239	MD4STEP(F1, b, c, d, a, in[15], 19);
240
241	MD4STEP(F2, a, b, c, d, in[ 0] + 0x5a827999,  3);
242	MD4STEP(F2, d, a, b, c, in[ 4] + 0x5a827999,  5);
243	MD4STEP(F2, c, d, a, b, in[ 8] + 0x5a827999,  9);
244	MD4STEP(F2, b, c, d, a, in[12] + 0x5a827999, 13);
245	MD4STEP(F2, a, b, c, d, in[ 1] + 0x5a827999,  3);
246	MD4STEP(F2, d, a, b, c, in[ 5] + 0x5a827999,  5);
247	MD4STEP(F2, c, d, a, b, in[ 9] + 0x5a827999,  9);
248	MD4STEP(F2, b, c, d, a, in[13] + 0x5a827999, 13);
249	MD4STEP(F2, a, b, c, d, in[ 2] + 0x5a827999,  3);
250	MD4STEP(F2, d, a, b, c, in[ 6] + 0x5a827999,  5);
251	MD4STEP(F2, c, d, a, b, in[10] + 0x5a827999,  9);
252	MD4STEP(F2, b, c, d, a, in[14] + 0x5a827999, 13);
253	MD4STEP(F2, a, b, c, d, in[ 3] + 0x5a827999,  3);
254	MD4STEP(F2, d, a, b, c, in[ 7] + 0x5a827999,  5);
255	MD4STEP(F2, c, d, a, b, in[11] + 0x5a827999,  9);
256	MD4STEP(F2, b, c, d, a, in[15] + 0x5a827999, 13);
257
258	MD4STEP(F3, a, b, c, d, in[ 0] + 0x6ed9eba1,  3);
259	MD4STEP(F3, d, a, b, c, in[ 8] + 0x6ed9eba1,  9);
260	MD4STEP(F3, c, d, a, b, in[ 4] + 0x6ed9eba1, 11);
261	MD4STEP(F3, b, c, d, a, in[12] + 0x6ed9eba1, 15);
262	MD4STEP(F3, a, b, c, d, in[ 2] + 0x6ed9eba1,  3);
263	MD4STEP(F3, d, a, b, c, in[10] + 0x6ed9eba1,  9);
264	MD4STEP(F3, c, d, a, b, in[ 6] + 0x6ed9eba1, 11);
265	MD4STEP(F3, b, c, d, a, in[14] + 0x6ed9eba1, 15);
266	MD4STEP(F3, a, b, c, d, in[ 1] + 0x6ed9eba1,  3);
267	MD4STEP(F3, d, a, b, c, in[ 9] + 0x6ed9eba1,  9);
268	MD4STEP(F3, c, d, a, b, in[ 5] + 0x6ed9eba1, 11);
269	MD4STEP(F3, b, c, d, a, in[13] + 0x6ed9eba1, 15);
270	MD4STEP(F3, a, b, c, d, in[ 3] + 0x6ed9eba1,  3);
271	MD4STEP(F3, d, a, b, c, in[11] + 0x6ed9eba1,  9);
272	MD4STEP(F3, c, d, a, b, in[ 7] + 0x6ed9eba1, 11);
273	MD4STEP(F3, b, c, d, a, in[15] + 0x6ed9eba1, 15);
274
275	state[0] += a;
276	state[1] += b;
277	state[2] += c;
278	state[3] += d;
279}
280/* ===== end - public domain MD4 implementation ===== */
281
282#endif /* INTERNAL_MD4 */
283