xref: /freebsd/contrib/ntp/libntp/lib/isc/md5.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*
2  * Copyright (C) 2004, 2005, 2007, 2009  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2000, 2001  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id: md5.c,v 1.16 2009/02/06 23:47:42 tbox Exp $ */
19 
20 /*! \file
21  * This code implements the MD5 message-digest algorithm.
22  * The algorithm is due to Ron Rivest.  This code was
23  * written by Colin Plumb in 1993, no copyright is claimed.
24  * This code is in the public domain; do with it what you wish.
25  *
26  * Equivalent code is available from RSA Data Security, Inc.
27  * This code has been tested against that, and is equivalent,
28  * except that you don't need to include two pages of legalese
29  * with every copy.
30  *
31  * To compute the message digest of a chunk of bytes, declare an
32  * MD5Context structure, pass it to MD5Init, call MD5Update as
33  * needed on buffers full of bytes, and then call MD5Final, which
34  * will fill a supplied 16-byte array with the digest.
35  */
36 
37 #include "config.h"
38 
39 #include <isc/assertions.h>
40 #include <isc/md5.h>
41 #include <isc/platform.h>
42 #include <isc/string.h>
43 #include <isc/types.h>
44 #include <isc/util.h>
45 
46 #ifdef ISC_PLATFORM_OPENSSLHASH
47 
48 void
49 isc_md5_init(isc_md5_t *ctx) {
50 	EVP_DigestInit(ctx, EVP_md5());
51 }
52 
53 void
54 isc_md5_invalidate(isc_md5_t *ctx) {
55 	EVP_MD_CTX_cleanup(ctx);
56 }
57 
58 void
59 isc_md5_update(isc_md5_t *ctx, const unsigned char *buf, unsigned int len) {
60 	EVP_DigestUpdate(ctx, (const void *) buf, (size_t) len);
61 }
62 
63 void
64 isc_md5_final(isc_md5_t *ctx, unsigned char *digest) {
65 	EVP_DigestFinal(ctx, digest, NULL);
66 }
67 
68 #else
69 
70 static void
71 byteSwap(isc_uint32_t *buf, unsigned words)
72 {
73 	unsigned char *p = (unsigned char *)buf;
74 
75 	do {
76 		*buf++ = (isc_uint32_t)((unsigned)p[3] << 8 | p[2]) << 16 |
77 			((unsigned)p[1] << 8 | p[0]);
78 		p += 4;
79 	} while (--words);
80 }
81 
82 /*!
83  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
84  * initialization constants.
85  */
86 void
87 isc_md5_init(isc_md5_t *ctx) {
88 	ctx->buf[0] = 0x67452301;
89 	ctx->buf[1] = 0xefcdab89;
90 	ctx->buf[2] = 0x98badcfe;
91 	ctx->buf[3] = 0x10325476;
92 
93 	ctx->bytes[0] = 0;
94 	ctx->bytes[1] = 0;
95 }
96 
97 void
98 isc_md5_invalidate(isc_md5_t *ctx) {
99 	memset(ctx, 0, sizeof(isc_md5_t));
100 }
101 
102 /*@{*/
103 /*! The four core functions - F1 is optimized somewhat */
104 
105 /* #define F1(x, y, z) (x & y | ~x & z) */
106 #define F1(x, y, z) (z ^ (x & (y ^ z)))
107 #define F2(x, y, z) F1(z, x, y)
108 #define F3(x, y, z) (x ^ y ^ z)
109 #define F4(x, y, z) (y ^ (x | ~z))
110 /*@}*/
111 
112 /*! This is the central step in the MD5 algorithm. */
113 #define MD5STEP(f,w,x,y,z,in,s) \
114 	 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
115 
116 /*!
117  * The core of the MD5 algorithm, this alters an existing MD5 hash to
118  * reflect the addition of 16 longwords of new data.  MD5Update blocks
119  * the data and converts bytes into longwords for this routine.
120  */
121 static void
122 transform(isc_uint32_t buf[4], isc_uint32_t const in[16]) {
123 	register isc_uint32_t a, b, c, d;
124 
125 	a = buf[0];
126 	b = buf[1];
127 	c = buf[2];
128 	d = buf[3];
129 
130 	MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
131 	MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
132 	MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
133 	MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
134 	MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
135 	MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
136 	MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
137 	MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
138 	MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
139 	MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
140 	MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
141 	MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
142 	MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
143 	MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
144 	MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
145 	MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
146 
147 	MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
148 	MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
149 	MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
150 	MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
151 	MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
152 	MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
153 	MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
154 	MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
155 	MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
156 	MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
157 	MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
158 	MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
159 	MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
160 	MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
161 	MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
162 	MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
163 
164 	MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
165 	MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
166 	MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
167 	MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
168 	MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
169 	MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
170 	MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
171 	MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
172 	MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
173 	MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
174 	MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
175 	MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
176 	MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
177 	MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
178 	MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
179 	MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
180 
181 	MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
182 	MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
183 	MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
184 	MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
185 	MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
186 	MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
187 	MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
188 	MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
189 	MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
190 	MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
191 	MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
192 	MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
193 	MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
194 	MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
195 	MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
196 	MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
197 
198 	buf[0] += a;
199 	buf[1] += b;
200 	buf[2] += c;
201 	buf[3] += d;
202 }
203 
204 /*!
205  * Update context to reflect the concatenation of another buffer full
206  * of bytes.
207  */
208 void
209 isc_md5_update(isc_md5_t *ctx, const unsigned char *buf, unsigned int len) {
210 	isc_uint32_t t;
211 
212 	/* Update byte count */
213 
214 	t = ctx->bytes[0];
215 	if ((ctx->bytes[0] = t + len) < t)
216 		ctx->bytes[1]++;	/* Carry from low to high */
217 
218 	t = 64 - (t & 0x3f);	/* Space available in ctx->in (at least 1) */
219 	if (t > len) {
220 		memcpy((unsigned char *)ctx->in + 64 - t, buf, len);
221 		return;
222 	}
223 	/* First chunk is an odd size */
224 	memcpy((unsigned char *)ctx->in + 64 - t, buf, t);
225 	byteSwap(ctx->in, 16);
226 	transform(ctx->buf, ctx->in);
227 	buf += t;
228 	len -= t;
229 
230 	/* Process data in 64-byte chunks */
231 	while (len >= 64) {
232 		memcpy(ctx->in, buf, 64);
233 		byteSwap(ctx->in, 16);
234 		transform(ctx->buf, ctx->in);
235 		buf += 64;
236 		len -= 64;
237 	}
238 
239 	/* Handle any remaining bytes of data. */
240 	memcpy(ctx->in, buf, len);
241 }
242 
243 /*!
244  * Final wrapup - pad to 64-byte boundary with the bit pattern
245  * 1 0* (64-bit count of bits processed, MSB-first)
246  */
247 void
248 isc_md5_final(isc_md5_t *ctx, unsigned char *digest) {
249 	int count = ctx->bytes[0] & 0x3f;    /* Number of bytes in ctx->in */
250 	unsigned char *p = (unsigned char *)ctx->in + count;
251 
252 	/* Set the first char of padding to 0x80.  There is always room. */
253 	*p++ = 0x80;
254 
255 	/* Bytes of padding needed to make 56 bytes (-8..55) */
256 	count = 56 - 1 - count;
257 
258 	if (count < 0) {	/* Padding forces an extra block */
259 		memset(p, 0, count + 8);
260 		byteSwap(ctx->in, 16);
261 		transform(ctx->buf, ctx->in);
262 		p = (unsigned char *)ctx->in;
263 		count = 56;
264 	}
265 	memset(p, 0, count);
266 	byteSwap(ctx->in, 14);
267 
268 	/* Append length in bits and transform */
269 	ctx->in[14] = ctx->bytes[0] << 3;
270 	ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
271 	transform(ctx->buf, ctx->in);
272 
273 	byteSwap(ctx->buf, 4);
274 	memcpy(digest, ctx->buf, 16);
275 	memset(ctx, 0, sizeof(isc_md5_t));	/* In case it's sensitive */
276 }
277 #endif
278