xref: /dragonfly/sys/kern/md5c.c (revision 6bd457ed)
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  * $FreeBSD: src/sys/kern/md5c.c,v 1.17 1999/12/29 04:54:39 peter Exp $
26  * $DragonFly: src/sys/kern/md5c.c,v 1.4 2005/04/30 23:04:21 swildner Exp $
27  *
28  * This code is the same as the code published by RSA Inc.  It has been
29  * edited for clarity and style only.
30  */
31 
32 #include <sys/types.h>
33 
34 #ifdef _KERNEL
35 #include <sys/systm.h>
36 #else
37 #include <string.h>
38 #endif
39 
40 #include <sys/md5.h>
41 
42 
43 #ifdef _KERNEL
44 #define memset(x,y,z)	bzero(x,z);
45 #define memcpy(x,y,z)	bcopy(y, x, z)
46 #endif
47 
48 #if defined(__i386__)
49 #define Encode memcpy
50 #define Decode memcpy
51 #else /* __i386__ */
52 
53 /*
54  * Encodes input (u_int32_t) into output (unsigned char). Assumes len is
55  * a multiple of 4.
56  */
57 
58 /* XXX not prototyped, and not compatible with memcpy(). */
59 static void
60 Encode (unsigned char *output, u_int32_t *input, unsigned int len)
61 {
62 	unsigned int i, j;
63 
64 	for (i = 0, j = 0; j < len; i++, j += 4) {
65 		output[j] = (unsigned char)(input[i] & 0xff);
66 		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
67 		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
68 		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
69 	}
70 }
71 
72 /*
73  * Decodes input (unsigned char) into output (u_int32_t). Assumes len is
74  * a multiple of 4.
75  */
76 
77 static void
78 Decode (u_int32_t *output, const unsigned char *input, unsigned int len)
79 {
80 	unsigned int i, j;
81 
82 	for (i = 0, j = 0; j < len; i++, j += 4)
83 		output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
84 		    (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
85 }
86 #endif /* i386 */
87 
88 static unsigned char PADDING[64] = {
89   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
90   0, 0, 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
92 };
93 
94 /* F, G, H and I are basic MD5 functions. */
95 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
96 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
97 #define H(x, y, z) ((x) ^ (y) ^ (z))
98 #define I(x, y, z) ((y) ^ ((x) | (~z)))
99 
100 /* ROTATE_LEFT rotates x left n bits. */
101 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
102 
103 /*
104  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
105  * Rotation is separate from addition to prevent recomputation.
106  */
107 #define FF(a, b, c, d, x, s, ac) { \
108 	(a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
109 	(a) = ROTATE_LEFT ((a), (s)); \
110 	(a) += (b); \
111 	}
112 #define GG(a, b, c, d, x, s, ac) { \
113 	(a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
114 	(a) = ROTATE_LEFT ((a), (s)); \
115 	(a) += (b); \
116 	}
117 #define HH(a, b, c, d, x, s, ac) { \
118 	(a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
119 	(a) = ROTATE_LEFT ((a), (s)); \
120 	(a) += (b); \
121 	}
122 #define II(a, b, c, d, x, s, ac) { \
123 	(a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
124 	(a) = ROTATE_LEFT ((a), (s)); \
125 	(a) += (b); \
126 	}
127 
128 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
129 
130 void
131 MD5Init (MD5_CTX *context)
132 {
133 
134 	context->count[0] = context->count[1] = 0;
135 
136 	/* Load magic initialization constants.  */
137 	context->state[0] = 0x67452301;
138 	context->state[1] = 0xefcdab89;
139 	context->state[2] = 0x98badcfe;
140 	context->state[3] = 0x10325476;
141 }
142 
143 /*
144  * MD5 block update operation. Continues an MD5 message-digest
145  * operation, processing another message block, and updating the
146  * context.
147  */
148 
149 void
150 MD5Update (MD5_CTX *context, const unsigned char *input, unsigned int inputLen)
151 {
152 	unsigned int i, index, partLen;
153 
154 	/* Compute number of bytes mod 64 */
155 	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
156 
157 	/* Update number of bits */
158 	if ((context->count[0] += ((u_int32_t)inputLen << 3))
159 	    < ((u_int32_t)inputLen << 3))
160 		context->count[1]++;
161 	context->count[1] += ((u_int32_t)inputLen >> 29);
162 
163 	partLen = 64 - index;
164 
165 	/* Transform as many times as possible. */
166 	if (inputLen >= partLen) {
167 		memcpy((void *)&context->buffer[index], (const void *)input,
168 		    partLen);
169 		MD5Transform (context->state, context->buffer);
170 
171 		for (i = partLen; i + 63 < inputLen; i += 64)
172 			MD5Transform (context->state, &input[i]);
173 
174 		index = 0;
175 	}
176 	else
177 		i = 0;
178 
179 	/* Buffer remaining input */
180 	memcpy ((void *)&context->buffer[index], (const void *)&input[i],
181 	    inputLen-i);
182 }
183 
184 /*
185  * MD5 padding. Adds padding followed by original length.
186  */
187 
188 void
189 MD5Pad (MD5_CTX *context)
190 {
191 	unsigned char bits[8];
192 	unsigned int index, padLen;
193 
194 	/* Save number of bits */
195 	Encode (bits, context->count, 8);
196 
197 	/* Pad out to 56 mod 64. */
198 	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
199 	padLen = (index < 56) ? (56 - index) : (120 - index);
200 	MD5Update (context, PADDING, padLen);
201 
202 	/* Append length (before padding) */
203 	MD5Update (context, bits, 8);
204 }
205 
206 /*
207  * MD5 finalization. Ends an MD5 message-digest operation, writing the
208  * the message digest and zeroizing the context.
209  */
210 
211 void
212 MD5Final (unsigned char digest[16], MD5_CTX *context)
213 {
214 	/* Do padding. */
215 	MD5Pad (context);
216 
217 	/* Store state in digest */
218 	Encode (digest, context->state, 16);
219 
220 	/* Zeroize sensitive information. */
221 	memset ((void *)context, 0, sizeof (*context));
222 }
223 
224 /* MD5 basic transformation. Transforms state based on block. */
225 
226 void
227 MD5Transform (u_int32_t state[4], const unsigned char block[64])
228 {
229 	u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
230 
231 	Decode (x, block, 64);
232 
233 	/* Round 1 */
234 #define S11 7
235 #define S12 12
236 #define S13 17
237 #define S14 22
238 	FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
239 	FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
240 	FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
241 	FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
242 	FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
243 	FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
244 	FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
245 	FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
246 	FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
247 	FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
248 	FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
249 	FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
250 	FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
251 	FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
252 	FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
253 	FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
254 
255 	/* Round 2 */
256 #define S21 5
257 #define S22 9
258 #define S23 14
259 #define S24 20
260 	GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
261 	GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
262 	GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
263 	GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
264 	GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
265 	GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
266 	GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
267 	GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
268 	GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
269 	GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
270 	GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
271 	GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
272 	GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
273 	GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
274 	GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
275 	GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
276 
277 	/* Round 3 */
278 #define S31 4
279 #define S32 11
280 #define S33 16
281 #define S34 23
282 	HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
283 	HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
284 	HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
285 	HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
286 	HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
287 	HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
288 	HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
289 	HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
290 	HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
291 	HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
292 	HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
293 	HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
294 	HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
295 	HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
296 	HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
297 	HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
298 
299 	/* Round 4 */
300 #define S41 6
301 #define S42 10
302 #define S43 15
303 #define S44 21
304 	II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
305 	II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
306 	II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
307 	II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
308 	II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
309 	II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
310 	II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
311 	II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
312 	II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
313 	II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
314 	II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
315 	II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
316 	II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
317 	II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
318 	II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
319 	II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
320 
321 	state[0] += a;
322 	state[1] += b;
323 	state[2] += c;
324 	state[3] += d;
325 
326 	/* Zeroize sensitive information. */
327 	memset ((void *)x, 0, sizeof (x));
328 }
329