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#ifndef HAVE_OPENSSL
39
40#include <string.h>
41
42#include "md5.h"
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 H2(x, y, z)			((x) ^ ((y) ^ (z)))
55#define I(x, y, z)			((y) ^ ((x) | ~(z)))
56
57/*
58 * The MD5 transformation for all four rounds.
59 */
60#define STEP(f, a, b, c, d, x, t, s) \
61	(a) += f((b), (c), (d)) + (x) + (t); \
62	(a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
63	(a) += (b);
64
65/*
66 * SET reads 4 input bytes in little-endian byte order and stores them
67 * in a properly aligned word in host byte order.
68 *
69 * The check for little-endian architectures that tolerate unaligned
70 * memory accesses is just an optimization.  Nothing will break if it
71 * doesn't work.
72 */
73#if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
74#define SET(n) \
75	(*(MD5_u32plus *)&ptr[(n) * 4])
76#define GET(n) \
77	SET(n)
78#else
79#define SET(n) \
80	(ctx->block[(n)] = \
81	(MD5_u32plus)ptr[(n) * 4] | \
82	((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \
83	((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \
84	((MD5_u32plus)ptr[(n) * 4 + 3] << 24))
85#define GET(n) \
86	(ctx->block[(n)])
87#endif
88
89/*
90 * This processes one or more 64-byte data blocks, but does NOT update
91 * the bit counters.  There are no alignment requirements.
92 */
93static const void *body(MD5_CTX *ctx, const void *data, unsigned long size)
94{
95	const unsigned char *ptr;
96	MD5_u32plus a, b, c, d;
97	MD5_u32plus saved_a, saved_b, saved_c, saved_d;
98
99	ptr = (const unsigned char *)data;
100
101	a = ctx->a;
102	b = ctx->b;
103	c = ctx->c;
104	d = ctx->d;
105
106	do {
107		saved_a = a;
108		saved_b = b;
109		saved_c = c;
110		saved_d = d;
111
112/* Round 1 */
113		STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
114		STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
115		STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
116		STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
117		STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
118		STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
119		STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
120		STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
121		STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
122		STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
123		STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
124		STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
125		STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
126		STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
127		STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
128		STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
129
130/* Round 2 */
131		STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
132		STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
133		STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
134		STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
135		STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
136		STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
137		STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
138		STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
139		STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
140		STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
141		STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
142		STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
143		STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
144		STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
145		STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
146		STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
147
148/* Round 3 */
149		STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
150		STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11)
151		STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
152		STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23)
153		STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
154		STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11)
155		STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
156		STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23)
157		STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
158		STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11)
159		STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
160		STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23)
161		STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
162		STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11)
163		STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
164		STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23)
165
166/* Round 4 */
167		STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
168		STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
169		STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
170		STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
171		STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
172		STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
173		STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
174		STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
175		STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
176		STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
177		STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
178		STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
179		STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
180		STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
181		STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
182		STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
183
184		a += saved_a;
185		b += saved_b;
186		c += saved_c;
187		d += saved_d;
188
189		ptr += 64;
190	} while (size -= 64);
191
192	ctx->a = a;
193	ctx->b = b;
194	ctx->c = c;
195	ctx->d = d;
196
197	return ptr;
198}
199
200void MD5_Init(MD5_CTX *ctx)
201{
202	ctx->a = 0x67452301;
203	ctx->b = 0xefcdab89;
204	ctx->c = 0x98badcfe;
205	ctx->d = 0x10325476;
206
207	ctx->lo = 0;
208	ctx->hi = 0;
209}
210
211void MD5_Update(MD5_CTX *ctx, const void *data, unsigned long size)
212{
213	MD5_u32plus saved_lo;
214	unsigned long used, available;
215
216	saved_lo = ctx->lo;
217	if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
218		ctx->hi++;
219	ctx->hi += size >> 29;
220
221	used = saved_lo & 0x3f;
222
223	if (used) {
224		available = 64 - used;
225
226		if (size < available) {
227			memcpy(&ctx->buffer[used], data, size);
228			return;
229		}
230
231		memcpy(&ctx->buffer[used], data, available);
232		data = (const unsigned char *)data + available;
233		size -= available;
234		body(ctx, ctx->buffer, 64);
235	}
236
237	if (size >= 64) {
238		data = body(ctx, data, size & ~(unsigned long)0x3f);
239		size &= 0x3f;
240	}
241
242	memcpy(ctx->buffer, data, size);
243}
244
245void MD5_Final(unsigned char *result, MD5_CTX *ctx)
246{
247	unsigned long used, available;
248
249	used = ctx->lo & 0x3f;
250
251	ctx->buffer[used++] = 0x80;
252
253	available = 64 - used;
254
255	if (available < 8) {
256		memset(&ctx->buffer[used], 0, available);
257		body(ctx, ctx->buffer, 64);
258		used = 0;
259		available = 64;
260	}
261
262	memset(&ctx->buffer[used], 0, available - 8);
263
264	ctx->lo <<= 3;
265	ctx->buffer[56] = ctx->lo;
266	ctx->buffer[57] = ctx->lo >> 8;
267	ctx->buffer[58] = ctx->lo >> 16;
268	ctx->buffer[59] = ctx->lo >> 24;
269	ctx->buffer[60] = ctx->hi;
270	ctx->buffer[61] = ctx->hi >> 8;
271	ctx->buffer[62] = ctx->hi >> 16;
272	ctx->buffer[63] = ctx->hi >> 24;
273
274	body(ctx, ctx->buffer, 64);
275
276	result[0] = ctx->a;
277	result[1] = ctx->a >> 8;
278	result[2] = ctx->a >> 16;
279	result[3] = ctx->a >> 24;
280	result[4] = ctx->b;
281	result[5] = ctx->b >> 8;
282	result[6] = ctx->b >> 16;
283	result[7] = ctx->b >> 24;
284	result[8] = ctx->c;
285	result[9] = ctx->c >> 8;
286	result[10] = ctx->c >> 16;
287	result[11] = ctx->c >> 24;
288	result[12] = ctx->d;
289	result[13] = ctx->d >> 8;
290	result[14] = ctx->d >> 16;
291	result[15] = ctx->d >> 24;
292
293	memset(ctx, 0, sizeof(*ctx));
294}
295
296#endif
297