1/*
2 * MD5 hash implementation and interface functions
3 * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10
11#include "common.h"
12#include "md5.h"
13#include "md5_i.h"
14#include "crypto.h"
15
16
17static void MD5Transform(u32 buf[4], u32 const in[16]);
18
19
20typedef struct MD5Context MD5_CTX;
21
22
23/**
24 * md5_vector - MD5 hash for data vector
25 * @num_elem: Number of elements in the data vector
26 * @addr: Pointers to the data areas
27 * @len: Lengths of the data blocks
28 * @mac: Buffer for the hash
29 * Returns: 0 on success, -1 of failure
30 */
31int md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
32{
33	MD5_CTX ctx;
34	size_t i;
35
36	MD5Init(&ctx);
37	for (i = 0; i < num_elem; i++)
38		MD5Update(&ctx, addr[i], len[i]);
39	MD5Final(mac, &ctx);
40	return 0;
41}
42
43
44/* ===== start - public domain MD5 implementation ===== */
45/*
46 * This code implements the MD5 message-digest algorithm.
47 * The algorithm is due to Ron Rivest.  This code was
48 * written by Colin Plumb in 1993, no copyright is claimed.
49 * This code is in the public domain; do with it what you wish.
50 *
51 * Equivalent code is available from RSA Data Security, Inc.
52 * This code has been tested against that, and is equivalent,
53 * except that you don't need to include two pages of legalese
54 * with every copy.
55 *
56 * To compute the message digest of a chunk of bytes, declare an
57 * MD5Context structure, pass it to MD5Init, call MD5Update as
58 * needed on buffers full of bytes, and then call MD5Final, which
59 * will fill a supplied 16-byte array with the digest.
60 */
61
62#ifndef WORDS_BIGENDIAN
63#define byteReverse(buf, len)	/* Nothing */
64#else
65/*
66 * Note: this code is harmless on little-endian machines.
67 */
68static void byteReverse(unsigned char *buf, unsigned longs)
69{
70    u32 t;
71    do {
72	t = (u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
73	    ((unsigned) buf[1] << 8 | buf[0]);
74	*(u32 *) buf = t;
75	buf += 4;
76    } while (--longs);
77}
78#endif
79
80/*
81 * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
82 * initialization constants.
83 */
84void MD5Init(struct MD5Context *ctx)
85{
86    ctx->buf[0] = 0x67452301;
87    ctx->buf[1] = 0xefcdab89;
88    ctx->buf[2] = 0x98badcfe;
89    ctx->buf[3] = 0x10325476;
90
91    ctx->bits[0] = 0;
92    ctx->bits[1] = 0;
93}
94
95/*
96 * Update context to reflect the concatenation of another buffer full
97 * of bytes.
98 */
99void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
100{
101    u32 t;
102
103    /* Update bitcount */
104
105    t = ctx->bits[0];
106    if ((ctx->bits[0] = t + ((u32) len << 3)) < t)
107	ctx->bits[1]++;		/* Carry from low to high */
108    ctx->bits[1] += len >> 29;
109
110    t = (t >> 3) & 0x3f;	/* Bytes already in shsInfo->data */
111
112    /* Handle any leading odd-sized chunks */
113
114    if (t) {
115	unsigned char *p = (unsigned char *) ctx->in + t;
116
117	t = 64 - t;
118	if (len < t) {
119	    os_memcpy(p, buf, len);
120	    return;
121	}
122	os_memcpy(p, buf, t);
123	byteReverse(ctx->in, 16);
124	MD5Transform(ctx->buf, (u32 *) ctx->in);
125	buf += t;
126	len -= t;
127    }
128    /* Process data in 64-byte chunks */
129
130    while (len >= 64) {
131	os_memcpy(ctx->in, buf, 64);
132	byteReverse(ctx->in, 16);
133	MD5Transform(ctx->buf, (u32 *) ctx->in);
134	buf += 64;
135	len -= 64;
136    }
137
138    /* Handle any remaining bytes of data. */
139
140    os_memcpy(ctx->in, buf, len);
141}
142
143/*
144 * Final wrapup - pad to 64-byte boundary with the bit pattern
145 * 1 0* (64-bit count of bits processed, MSB-first)
146 */
147void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
148{
149    unsigned count;
150    unsigned char *p;
151
152    /* Compute number of bytes mod 64 */
153    count = (ctx->bits[0] >> 3) & 0x3F;
154
155    /* Set the first char of padding to 0x80.  This is safe since there is
156       always at least one byte free */
157    p = ctx->in + count;
158    *p++ = 0x80;
159
160    /* Bytes of padding needed to make 64 bytes */
161    count = 64 - 1 - count;
162
163    /* Pad out to 56 mod 64 */
164    if (count < 8) {
165	/* Two lots of padding:  Pad the first block to 64 bytes */
166	os_memset(p, 0, count);
167	byteReverse(ctx->in, 16);
168	MD5Transform(ctx->buf, (u32 *) ctx->in);
169
170	/* Now fill the next block with 56 bytes */
171	os_memset(ctx->in, 0, 56);
172    } else {
173	/* Pad block to 56 bytes */
174	os_memset(p, 0, count - 8);
175    }
176    byteReverse(ctx->in, 14);
177
178    /* Append length in bits and transform */
179    ((u32 *) aliasing_hide_typecast(ctx->in, u32))[14] = ctx->bits[0];
180    ((u32 *) aliasing_hide_typecast(ctx->in, u32))[15] = ctx->bits[1];
181
182    MD5Transform(ctx->buf, (u32 *) ctx->in);
183    byteReverse((unsigned char *) ctx->buf, 4);
184    os_memcpy(digest, ctx->buf, 16);
185    os_memset(ctx, 0, sizeof(*ctx));	/* In case it's sensitive */
186}
187
188/* The four core functions - F1 is optimized somewhat */
189
190/* #define F1(x, y, z) (x & y | ~x & z) */
191#define F1(x, y, z) (z ^ (x & (y ^ z)))
192#define F2(x, y, z) F1(z, x, y)
193#define F3(x, y, z) (x ^ y ^ z)
194#define F4(x, y, z) (y ^ (x | ~z))
195
196/* This is the central step in the MD5 algorithm. */
197#define MD5STEP(f, w, x, y, z, data, s) \
198	( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
199
200/*
201 * The core of the MD5 algorithm, this alters an existing MD5 hash to
202 * reflect the addition of 16 longwords of new data.  MD5Update blocks
203 * the data and converts bytes into longwords for this routine.
204 */
205static void MD5Transform(u32 buf[4], u32 const in[16])
206{
207    register u32 a, b, c, d;
208
209    a = buf[0];
210    b = buf[1];
211    c = buf[2];
212    d = buf[3];
213
214    MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
215    MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
216    MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
217    MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
218    MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
219    MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
220    MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
221    MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
222    MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
223    MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
224    MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
225    MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
226    MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
227    MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
228    MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
229    MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
230
231    MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
232    MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
233    MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
234    MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
235    MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
236    MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
237    MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
238    MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
239    MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
240    MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
241    MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
242    MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
243    MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
244    MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
245    MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
246    MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
247
248    MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
249    MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
250    MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
251    MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
252    MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
253    MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
254    MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
255    MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
256    MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
257    MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
258    MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
259    MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
260    MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
261    MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
262    MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
263    MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
264
265    MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
266    MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
267    MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
268    MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
269    MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
270    MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
271    MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
272    MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
273    MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
274    MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
275    MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
276    MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
277    MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
278    MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
279    MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
280    MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
281
282    buf[0] += a;
283    buf[1] += b;
284    buf[2] += c;
285    buf[3] += d;
286}
287/* ===== end - public domain MD5 implementation ===== */
288