1/*-
2 * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
3 *
4 * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
5 * rights reserved.
6 *
7 * License to copy and use this software is granted provided that it
8 * is identified as the "RSA Data Security, Inc. MD5 Message-Digest
9 * Algorithm" in all material mentioning or referencing this software
10 * or this function.
11 *
12 * License is also granted to make and use derivative works provided
13 * that such works are identified as "derived from the RSA Data
14 * Security, Inc. MD5 Message-Digest Algorithm" in all material
15 * mentioning or referencing the derived work.
16 *
17 * RSA Data Security, Inc. makes no representations concerning either
18 * the merchantability of this software or the suitability of this
19 * software for any particular purpose. It is provided "as is"
20 * without express or implied warranty of any kind.
21 *
22 * These notices must be retained in any copies of any part of this
23 * documentation and/or software.
24 *
25 * This code is the same as the code published by RSA Inc.  It has been
26 * edited for clarity and style only.
27 */
28
29/*
30 * This file should be kept in sync with src/lib/libmd/md5c.c
31 */
32
33#include <sys/types.h>
34
35#ifdef _KERNEL
36#include <sys/systm.h>
37#else
38#include <string.h>
39#endif
40
41#include <machine/endian.h>
42#include <sys/endian.h>
43#include <sys/md5.h>
44
45static void MD5Transform(uint32_t [4], const unsigned char [64]);
46
47#if (BYTE_ORDER == LITTLE_ENDIAN)
48#define Encode memcpy
49#define Decode memcpy
50#else
51
52/*
53 * Encodes input (uint32_t) into output (unsigned char). Assumes len is
54 * a multiple of 4.
55 */
56
57static void
58Encode (unsigned char *output, uint32_t *input, unsigned int len)
59{
60	unsigned int i;
61	uint32_t ip;
62
63	for (i = 0; i < len / 4; i++) {
64		ip = input[i];
65		*output++ = ip;
66		*output++ = ip >> 8;
67		*output++ = ip >> 16;
68		*output++ = ip >> 24;
69	}
70}
71
72/*
73 * Decodes input (unsigned char) into output (uint32_t). Assumes len is
74 * a multiple of 4.
75 */
76
77static void
78Decode (uint32_t *output, const unsigned char *input, unsigned int len)
79{
80	unsigned int i;
81
82	for (i = 0; i < len; i += 4) {
83		*output++ = input[i] | (input[i+1] << 8) | (input[i+2] << 16) |
84		    (input[i+3] << 24);
85	}
86}
87#endif
88
89static unsigned char PADDING[64] = {
90  0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
91  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
92  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
93};
94
95/* F, G, H and I are basic MD5 functions. */
96#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
97#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
98#define H(x, y, z) ((x) ^ (y) ^ (z))
99#define I(x, y, z) ((y) ^ ((x) | (~z)))
100
101/* ROTATE_LEFT rotates x left n bits. */
102#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
103
104/*
105 * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
106 * Rotation is separate from addition to prevent recomputation.
107 */
108#define FF(a, b, c, d, x, s, ac) { \
109	(a) += F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
110	(a) = ROTATE_LEFT ((a), (s)); \
111	(a) += (b); \
112	}
113#define GG(a, b, c, d, x, s, ac) { \
114	(a) += G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
115	(a) = ROTATE_LEFT ((a), (s)); \
116	(a) += (b); \
117	}
118#define HH(a, b, c, d, x, s, ac) { \
119	(a) += H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
120	(a) = ROTATE_LEFT ((a), (s)); \
121	(a) += (b); \
122	}
123#define II(a, b, c, d, x, s, ac) { \
124	(a) += I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
125	(a) = ROTATE_LEFT ((a), (s)); \
126	(a) += (b); \
127	}
128
129/* MD5 initialization. Begins an MD5 operation, writing a new context. */
130
131void
132MD5Init(MD5_CTX *context)
133{
134
135	context->count[0] = context->count[1] = 0;
136
137	/* Load magic initialization constants.  */
138	context->state[0] = 0x67452301;
139	context->state[1] = 0xefcdab89;
140	context->state[2] = 0x98badcfe;
141	context->state[3] = 0x10325476;
142}
143
144/*
145 * MD5 block update operation. Continues an MD5 message-digest
146 * operation, processing another message block, and updating the
147 * context.
148 */
149
150void
151MD5Update(MD5_CTX *context, const void *in, unsigned int inputLen)
152{
153	unsigned int i, index, partLen;
154	const unsigned char *input = in;
155
156	/* Compute number of bytes mod 64 */
157	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
158
159	/* Update number of bits */
160	if ((context->count[0] += ((uint32_t)inputLen << 3))
161	    < ((uint32_t)inputLen << 3))
162		context->count[1]++;
163	context->count[1] += ((uint32_t)inputLen >> 29);
164
165	partLen = 64 - index;
166
167	/* Transform as many times as possible. */
168	if (inputLen >= partLen) {
169		memcpy((void *)&context->buffer[index], (const void *)input,
170		    partLen);
171		MD5Transform (context->state, context->buffer);
172
173		for (i = partLen; i + 63 < inputLen; i += 64)
174			MD5Transform (context->state, &input[i]);
175
176		index = 0;
177	}
178	else
179		i = 0;
180
181	/* Buffer remaining input */
182	memcpy ((void *)&context->buffer[index], (const void *)&input[i],
183	    inputLen-i);
184}
185
186/*
187 * MD5 padding. Adds padding followed by original length.
188 */
189
190static void
191MD5Pad(MD5_CTX *context)
192{
193	unsigned char bits[8];
194	unsigned int index, padLen;
195
196	/* Save number of bits */
197	Encode (bits, context->count, 8);
198
199	/* Pad out to 56 mod 64. */
200	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
201	padLen = (index < 56) ? (56 - index) : (120 - index);
202	MD5Update (context, PADDING, padLen);
203
204	/* Append length (before padding) */
205	MD5Update (context, bits, 8);
206}
207
208/*
209 * MD5 finalization. Ends an MD5 message-digest operation, writing the
210 * the message digest and zeroizing the context.
211 */
212
213void
214MD5Final(unsigned char digest[static MD5_DIGEST_LENGTH], MD5_CTX *context)
215{
216	/* Do padding. */
217	MD5Pad (context);
218
219	/* Store state in digest */
220	Encode (digest, context->state, MD5_DIGEST_LENGTH);
221
222	/* Zeroize sensitive information. */
223	memset (context, 0, sizeof (*context));
224}
225
226/* MD5 basic transformation. Transforms state based on block. */
227
228static void
229MD5Transform(uint32_t state[4], const unsigned char block[64])
230{
231	uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
232
233	Decode (x, block, 64);
234
235	/* Round 1 */
236#define S11 7
237#define S12 12
238#define S13 17
239#define S14 22
240	FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
241	FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
242	FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
243	FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
244	FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
245	FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
246	FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
247	FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
248	FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
249	FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
250	FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
251	FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
252	FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
253	FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
254	FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
255	FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
256
257	/* Round 2 */
258#define S21 5
259#define S22 9
260#define S23 14
261#define S24 20
262	GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
263	GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
264	GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
265	GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
266	GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
267	GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
268	GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
269	GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
270	GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
271	GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
272	GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
273	GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
274	GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
275	GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
276	GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
277	GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
278
279	/* Round 3 */
280#define S31 4
281#define S32 11
282#define S33 16
283#define S34 23
284	HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
285	HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
286	HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
287	HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
288	HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
289	HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
290	HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
291	HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
292	HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
293	HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
294	HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
295	HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
296	HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
297	HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
298	HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
299	HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
300
301	/* Round 4 */
302#define S41 6
303#define S42 10
304#define S43 15
305#define S44 21
306	II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
307	II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
308	II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
309	II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
310	II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
311	II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
312	II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
313	II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
314	II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
315	II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
316	II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
317	II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
318	II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
319	II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
320	II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
321	II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
322
323	state[0] += a;
324	state[1] += b;
325	state[2] += c;
326	state[3] += d;
327
328	/* Zeroize sensitive information. */
329	memset ((void *)x, 0, sizeof (x));
330}
331