1/*
2 * This is an OpenSSL-compatible implementation of the RSA Data Security, Inc.
3 * MD5 Message-Digest Algorithm (RFC 1321).
4 *
5 * Homepage:
6 * http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5
7 *
8 * Author:
9 * Alexander Peslyak, better known as Solar Designer <solar at openwall.com>
10 *
11 * This software was written by Alexander Peslyak in 2001.  No copyright is
12 * claimed, and the software is hereby placed in the public domain.
13 * In case this attempt to disclaim copyright and place the software in the
14 * public domain is deemed null and void, then the software is
15 * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the
16 * general public under the following terms:
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted.
20 *
21 * There's ABSOLUTELY NO WARRANTY, express or implied.
22 *
23 * (This is a heavily cut-down "BSD license".)
24 *
25 * This differs from Colin Plumb's older public domain implementation in that
26 * no exactly 32-bit integer data type is required (any 32-bit or wider
27 * unsigned integer data type will do), there's no compile-time endianness
28 * configuration, and the function prototypes match OpenSSL's.  No code from
29 * Colin Plumb's implementation has been reused; this comment merely compares
30 * the properties of the two independent implementations.
31 *
32 * The primary goals of this implementation are portability and ease of use.
33 * It is meant to be fast, but not as fast as possible.  Some known
34 * optimizations are not included to reduce source code size and avoid
35 * compile-time configuration.
36 */
37
38
39#include "md5.h"
40
41#include <string.h>
42
43
44/*
45 * The basic MD5 functions.
46 *
47 * F and G are optimized compared to their RFC 1321 definitions for
48 * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
49 * implementation.
50 */
51#define F(x, y, z)			((z) ^ ((x) & ((y) ^ (z))))
52#define G(x, y, z)			((y) ^ ((z) & ((x) ^ (y))))
53#define H(x, y, z)			((x) ^ (y) ^ (z))
54#define I(x, y, z)			((y) ^ ((x) | ~(z)))
55
56/*
57 * The MD5 transformation for all four rounds.
58 */
59#define STEP(f, a, b, c, d, x, t, s) \
60	(a) += f((b), (c), (d)) + (x) + (t); \
61	(a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
62	(a) += (b);
63
64/*
65 * SET reads 4 input bytes in little-endian byte order and stores them
66 * in a properly aligned word in host byte order.
67 *
68 * The check for little-endian architectures that tolerate unaligned
69 * memory accesses is just an optimization.  Nothing will break if it
70 * doesn't work.
71 */
72#if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
73#define SET(n) \
74	(*(MD5_u32plus *)&ptr[(n) * 4])
75#define GET(n) \
76	SET(n)
77#else
78#define SET(n) \
79	(ctx->block[(n)] = \
80	(MD5_u32plus)ptr[(n) * 4] | \
81	((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \
82	((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \
83	((MD5_u32plus)ptr[(n) * 4 + 3] << 24))
84#define GET(n) \
85	(ctx->block[(n)])
86#endif
87
88
89namespace BPrivate {
90
91/*
92 * This processes one or more 64-byte data blocks, but does NOT update
93 * the bit counters.  There are no alignment requirements.
94 */
95static const void *body(MD5_CTX *ctx, const void *data, unsigned long size)
96{
97	const unsigned char *ptr;
98	MD5_u32plus a, b, c, d;
99	MD5_u32plus saved_a, saved_b, saved_c, saved_d;
100
101	ptr = (const unsigned char*)data;
102
103	a = ctx->a;
104	b = ctx->b;
105	c = ctx->c;
106	d = ctx->d;
107
108	do {
109		saved_a = a;
110		saved_b = b;
111		saved_c = c;
112		saved_d = d;
113
114/* Round 1 */
115		STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
116		STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
117		STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
118		STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
119		STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
120		STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
121		STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
122		STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
123		STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
124		STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
125		STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
126		STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
127		STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
128		STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
129		STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
130		STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
131
132/* Round 2 */
133		STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
134		STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
135		STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
136		STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
137		STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
138		STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
139		STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
140		STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
141		STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
142		STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
143		STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
144		STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
145		STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
146		STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
147		STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
148		STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
149
150/* Round 3 */
151		STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
152		STEP(H, d, a, b, c, GET(8), 0x8771f681, 11)
153		STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
154		STEP(H, b, c, d, a, GET(14), 0xfde5380c, 23)
155		STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
156		STEP(H, d, a, b, c, GET(4), 0x4bdecfa9, 11)
157		STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
158		STEP(H, b, c, d, a, GET(10), 0xbebfbc70, 23)
159		STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
160		STEP(H, d, a, b, c, GET(0), 0xeaa127fa, 11)
161		STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
162		STEP(H, b, c, d, a, GET(6), 0x04881d05, 23)
163		STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
164		STEP(H, d, a, b, c, GET(12), 0xe6db99e5, 11)
165		STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
166		STEP(H, b, c, d, a, GET(2), 0xc4ac5665, 23)
167
168/* Round 4 */
169		STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
170		STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
171		STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
172		STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
173		STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
174		STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
175		STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
176		STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
177		STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
178		STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
179		STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
180		STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
181		STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
182		STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
183		STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
184		STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
185
186		a += saved_a;
187		b += saved_b;
188		c += saved_c;
189		d += saved_d;
190
191		ptr += 64;
192	} while (size -= 64);
193
194	ctx->a = a;
195	ctx->b = b;
196	ctx->c = c;
197	ctx->d = d;
198
199	return ptr;
200}
201
202void MD5_Init(MD5_CTX *ctx)
203{
204	ctx->a = 0x67452301;
205	ctx->b = 0xefcdab89;
206	ctx->c = 0x98badcfe;
207	ctx->d = 0x10325476;
208
209	ctx->lo = 0;
210	ctx->hi = 0;
211}
212
213void MD5_Update(MD5_CTX *ctx, const void *data, unsigned long size)
214{
215	MD5_u32plus saved_lo;
216	unsigned long used, free;
217
218	saved_lo = ctx->lo;
219	if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
220		ctx->hi++;
221	ctx->hi += size >> 29;
222
223	used = saved_lo & 0x3f;
224
225	if (used) {
226		free = 64 - used;
227
228		if (size < free) {
229			memcpy(&ctx->buffer[used], data, size);
230			return;
231		}
232
233		memcpy(&ctx->buffer[used], data, free);
234		data = (unsigned char *)data + free;
235		size -= free;
236		body(ctx, ctx->buffer, 64);
237	}
238
239	if (size >= 64) {
240		data = body(ctx, data, size & ~(unsigned long)0x3f);
241		size &= 0x3f;
242	}
243
244	memcpy(ctx->buffer, data, size);
245}
246
247void MD5_Final(unsigned char *result, MD5_CTX *ctx)
248{
249	unsigned long used, free;
250
251	used = ctx->lo & 0x3f;
252
253	ctx->buffer[used++] = 0x80;
254
255	free = 64 - used;
256
257	if (free < 8) {
258		memset(&ctx->buffer[used], 0, free);
259		body(ctx, ctx->buffer, 64);
260		used = 0;
261		free = 64;
262	}
263
264	memset(&ctx->buffer[used], 0, free - 8);
265
266	ctx->lo <<= 3;
267	ctx->buffer[56] = ctx->lo;
268	ctx->buffer[57] = ctx->lo >> 8;
269	ctx->buffer[58] = ctx->lo >> 16;
270	ctx->buffer[59] = ctx->lo >> 24;
271	ctx->buffer[60] = ctx->hi;
272	ctx->buffer[61] = ctx->hi >> 8;
273	ctx->buffer[62] = ctx->hi >> 16;
274	ctx->buffer[63] = ctx->hi >> 24;
275
276	body(ctx, ctx->buffer, 64);
277
278	result[0] = ctx->a;
279	result[1] = ctx->a >> 8;
280	result[2] = ctx->a >> 16;
281	result[3] = ctx->a >> 24;
282	result[4] = ctx->b;
283	result[5] = ctx->b >> 8;
284	result[6] = ctx->b >> 16;
285	result[7] = ctx->b >> 24;
286	result[8] = ctx->c;
287	result[9] = ctx->c >> 8;
288	result[10] = ctx->c >> 16;
289	result[11] = ctx->c >> 24;
290	result[12] = ctx->d;
291	result[13] = ctx->d >> 8;
292	result[14] = ctx->d >> 16;
293	result[15] = ctx->d >> 24;
294
295	memset(ctx, 0, sizeof(*ctx));
296}
297
298};
299