xref: /freebsd/sys/kern/md5c.c (revision 7f3dea244c40159a41ab22da77a434d7c5b5e85a)
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  * $Id: md5c.c,v 1.14 1998/05/01 16:40:19 bde Exp $
26  *
27  * This code is the same as the code published by RSA Inc.  It has been
28  * edited for clarity and style only.
29  */
30 
31 #include <sys/types.h>
32 
33 #ifdef KERNEL
34 #include <sys/systm.h>
35 #else
36 #include <string.h>
37 #endif
38 
39 #include <sys/md5.h>
40 
41 
42 #ifdef KERNEL
43 #define memset(x,y,z)	bzero(x,z);
44 #define memcpy(x,y,z)	bcopy(y, x, z)
45 #endif
46 
47 #if defined(__i386__) || defined(__alpha__)
48 #define Encode memcpy
49 #define Decode memcpy
50 #else /* __i386__ */
51 
52 /*
53  * Encodes input (u_int32_t) into output (unsigned char). Assumes len is
54  * a multiple of 4.
55  */
56 
57 /* XXX not prototyped, and not compatible with memcpy(). */
58 static void
59 Encode (output, input, len)
60 	unsigned char *output;
61 	u_int32_t *input;
62 	unsigned int len;
63 {
64 	unsigned int i, j;
65 
66 	for (i = 0, j = 0; j < len; i++, j += 4) {
67 		output[j] = (unsigned char)(input[i] & 0xff);
68 		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
69 		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
70 		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
71 	}
72 }
73 
74 /*
75  * Decodes input (unsigned char) into output (u_int32_t). Assumes len is
76  * a multiple of 4.
77  */
78 
79 static void
80 Decode (output, input, len)
81 	u_int32_t *output;
82 	const unsigned char *input;
83 	unsigned int len;
84 {
85 	unsigned int i, j;
86 
87 	for (i = 0, j = 0; j < len; i++, j += 4)
88 		output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
89 		    (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
90 }
91 #endif /* i386 */
92 
93 static unsigned char PADDING[64] = {
94   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
95   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
96   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
97 };
98 
99 /* F, G, H and I are basic MD5 functions. */
100 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
101 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
102 #define H(x, y, z) ((x) ^ (y) ^ (z))
103 #define I(x, y, z) ((y) ^ ((x) | (~z)))
104 
105 /* ROTATE_LEFT rotates x left n bits. */
106 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
107 
108 /*
109  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
110  * Rotation is separate from addition to prevent recomputation.
111  */
112 #define FF(a, b, c, d, x, s, ac) { \
113 	(a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
114 	(a) = ROTATE_LEFT ((a), (s)); \
115 	(a) += (b); \
116 	}
117 #define GG(a, b, c, d, x, s, ac) { \
118 	(a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
119 	(a) = ROTATE_LEFT ((a), (s)); \
120 	(a) += (b); \
121 	}
122 #define HH(a, b, c, d, x, s, ac) { \
123 	(a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
124 	(a) = ROTATE_LEFT ((a), (s)); \
125 	(a) += (b); \
126 	}
127 #define II(a, b, c, d, x, s, ac) { \
128 	(a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
129 	(a) = ROTATE_LEFT ((a), (s)); \
130 	(a) += (b); \
131 	}
132 
133 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
134 
135 void
136 MD5Init (context)
137 	MD5_CTX *context;
138 {
139 
140 	context->count[0] = context->count[1] = 0;
141 
142 	/* Load magic initialization constants.  */
143 	context->state[0] = 0x67452301;
144 	context->state[1] = 0xefcdab89;
145 	context->state[2] = 0x98badcfe;
146 	context->state[3] = 0x10325476;
147 }
148 
149 /*
150  * MD5 block update operation. Continues an MD5 message-digest
151  * operation, processing another message block, and updating the
152  * context.
153  */
154 
155 void
156 MD5Update (context, input, inputLen)
157 	MD5_CTX *context;
158 	const unsigned char *input;
159 	unsigned int inputLen;
160 {
161 	unsigned int i, index, partLen;
162 
163 	/* Compute number of bytes mod 64 */
164 	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
165 
166 	/* Update number of bits */
167 	if ((context->count[0] += ((u_int32_t)inputLen << 3))
168 	    < ((u_int32_t)inputLen << 3))
169 		context->count[1]++;
170 	context->count[1] += ((u_int32_t)inputLen >> 29);
171 
172 	partLen = 64 - index;
173 
174 	/* Transform as many times as possible. */
175 	if (inputLen >= partLen) {
176 		memcpy((void *)&context->buffer[index], (const void *)input,
177 		    partLen);
178 		MD5Transform (context->state, context->buffer);
179 
180 		for (i = partLen; i + 63 < inputLen; i += 64)
181 			MD5Transform (context->state, &input[i]);
182 
183 		index = 0;
184 	}
185 	else
186 		i = 0;
187 
188 	/* Buffer remaining input */
189 	memcpy ((void *)&context->buffer[index], (const void *)&input[i],
190 	    inputLen-i);
191 }
192 
193 /*
194  * MD5 padding. Adds padding followed by original length.
195  */
196 
197 void
198 MD5Pad (context)
199 	MD5_CTX *context;
200 {
201 	unsigned char bits[8];
202 	unsigned int index, padLen;
203 
204 	/* Save number of bits */
205 	Encode (bits, context->count, 8);
206 
207 	/* Pad out to 56 mod 64. */
208 	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
209 	padLen = (index < 56) ? (56 - index) : (120 - index);
210 	MD5Update (context, PADDING, padLen);
211 
212 	/* Append length (before padding) */
213 	MD5Update (context, bits, 8);
214 }
215 
216 /*
217  * MD5 finalization. Ends an MD5 message-digest operation, writing the
218  * the message digest and zeroizing the context.
219  */
220 
221 void
222 MD5Final (digest, context)
223 	unsigned char digest[16];
224 	MD5_CTX *context;
225 {
226 	/* Do padding. */
227 	MD5Pad (context);
228 
229 	/* Store state in digest */
230 	Encode (digest, context->state, 16);
231 
232 	/* Zeroize sensitive information. */
233 	memset ((void *)context, 0, sizeof (*context));
234 }
235 
236 /* MD5 basic transformation. Transforms state based on block. */
237 
238 void
239 MD5Transform (state, block)
240 	u_int32_t state[4];
241 	const unsigned char block[64];
242 {
243 	u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
244 
245 	Decode (x, block, 64);
246 
247 	/* Round 1 */
248 #define S11 7
249 #define S12 12
250 #define S13 17
251 #define S14 22
252 	FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
253 	FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
254 	FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
255 	FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
256 	FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
257 	FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
258 	FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
259 	FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
260 	FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
261 	FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
262 	FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
263 	FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
264 	FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
265 	FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
266 	FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
267 	FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
268 
269 	/* Round 2 */
270 #define S21 5
271 #define S22 9
272 #define S23 14
273 #define S24 20
274 	GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
275 	GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
276 	GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
277 	GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
278 	GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
279 	GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
280 	GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
281 	GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
282 	GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
283 	GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
284 	GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
285 	GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
286 	GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
287 	GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
288 	GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
289 	GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
290 
291 	/* Round 3 */
292 #define S31 4
293 #define S32 11
294 #define S33 16
295 #define S34 23
296 	HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
297 	HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
298 	HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
299 	HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
300 	HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
301 	HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
302 	HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
303 	HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
304 	HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
305 	HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
306 	HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
307 	HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
308 	HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
309 	HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
310 	HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
311 	HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
312 
313 	/* Round 4 */
314 #define S41 6
315 #define S42 10
316 #define S43 15
317 #define S44 21
318 	II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
319 	II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
320 	II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
321 	II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
322 	II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
323 	II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
324 	II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
325 	II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
326 	II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
327 	II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
328 	II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
329 	II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
330 	II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
331 	II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
332 	II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
333 	II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
334 
335 	state[0] += a;
336 	state[1] += b;
337 	state[2] += c;
338 	state[3] += d;
339 
340 	/* Zeroize sensitive information. */
341 	memset ((void *)x, 0, sizeof (x));
342 }
343