1 /*
2 * This code implements the MD5 message-digest algorithm.
3 * The algorithm is due to Ron Rivest. This code was
4 * written by Colin Plumb in 1993, no copyright is claimed.
5 * This code is in the public domain; do with it what you wish.
6 *
7 * Equivalent code is available from RSA Data Security, Inc.
8 * This code has been tested against that, and is equivalent,
9 * except that you don't need to include two pages of legalese
10 * with every copy.
11 *
12 * To compute the message digest of a chunk of bytes, declare an
13 * MD5Context structure, pass it to MD5Init, call MD5Update as
14 * needed on buffers full of bytes, and then call MD5Final, which
15 * will fill a supplied 16-byte array with the digest.
16 */
17
18 /* This code was modified in 1997 by Jim Kingdon of Cyclic Software to
19 not require an integer type which is exactly 32 bits. This work
20 draws on the changes for the same purpose by Tatu Ylonen
21 <ylo@cs.hut.fi> as part of SSH, but since I didn't actually use
22 that code, there is no copyright issue. I hereby disclaim
23 copyright in any changes I have made; this code remains in the
24 public domain. */
25
26 /* Note regarding cvs_* namespace: this avoids potential conflicts
27 with libraries such as some versions of Kerberos. No particular
28 need to worry about whether the system supplies an MD5 library, as
29 this file is only about 3k of object code. */
30
31 #ifdef HAVE_CONFIG_H
32 #include "config.h"
33 #endif
34
35 #include <string.h> /* for memcpy() and memset() */
36
37 /* Add prototype support. */
38 #ifndef PROTO
39 #if defined (USE_PROTOTYPES) ? USE_PROTOTYPES : defined (__STDC__)
40 #define PROTO(ARGS) ARGS
41 #else
42 #define PROTO(ARGS) ()
43 #endif
44 #endif
45
46 #include "md5.h"
47
48 /* Little-endian byte-swapping routines. Note that these do not
49 depend on the size of datatypes such as cvs_uint32, nor do they require
50 us to detect the endianness of the machine we are running on. It
51 is possible they should be macros for speed, but I would be
52 surprised if they were a performance bottleneck for MD5. */
53
54 static cvs_uint32
getu32(addr)55 getu32 (addr)
56 const unsigned char *addr;
57 {
58 return (((((unsigned long)addr[3] << 8) | addr[2]) << 8)
59 | addr[1]) << 8 | addr[0];
60 }
61
62 static void
putu32(data,addr)63 putu32 (data, addr)
64 cvs_uint32 data;
65 unsigned char *addr;
66 {
67 addr[0] = (unsigned char)data;
68 addr[1] = (unsigned char)(data >> 8);
69 addr[2] = (unsigned char)(data >> 16);
70 addr[3] = (unsigned char)(data >> 24);
71 }
72
73 /*
74 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
75 * initialization constants.
76 */
77 void
cvs_MD5Init(ctx)78 cvs_MD5Init (ctx)
79 struct cvs_MD5Context *ctx;
80 {
81 ctx->buf[0] = 0x67452301;
82 ctx->buf[1] = 0xefcdab89;
83 ctx->buf[2] = 0x98badcfe;
84 ctx->buf[3] = 0x10325476;
85
86 ctx->bits[0] = 0;
87 ctx->bits[1] = 0;
88 }
89
90 /*
91 * Update context to reflect the concatenation of another buffer full
92 * of bytes.
93 */
94 void
cvs_MD5Update(ctx,buf,len)95 cvs_MD5Update (ctx, buf, len)
96 struct cvs_MD5Context *ctx;
97 unsigned char const *buf;
98 unsigned len;
99 {
100 cvs_uint32 t;
101
102 /* Update bitcount */
103
104 t = ctx->bits[0];
105 if ((ctx->bits[0] = (t + ((cvs_uint32)len << 3)) & 0xffffffff) < t)
106 ctx->bits[1]++; /* Carry from low to high */
107 ctx->bits[1] += len >> 29;
108
109 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
110
111 /* Handle any leading odd-sized chunks */
112
113 if ( t ) {
114 unsigned char *p = ctx->in + t;
115
116 t = 64-t;
117 if (len < t) {
118 memcpy(p, buf, len);
119 return;
120 }
121 memcpy(p, buf, t);
122 cvs_MD5Transform (ctx->buf, ctx->in);
123 buf += t;
124 len -= t;
125 }
126
127 /* Process data in 64-byte chunks */
128
129 while (len >= 64) {
130 memcpy(ctx->in, buf, 64);
131 cvs_MD5Transform (ctx->buf, ctx->in);
132 buf += 64;
133 len -= 64;
134 }
135
136 /* Handle any remaining bytes of data. */
137
138 memcpy(ctx->in, buf, len);
139 }
140
141 /*
142 * Final wrapup - pad to 64-byte boundary with the bit pattern
143 * 1 0* (64-bit count of bits processed, MSB-first)
144 */
145 void
cvs_MD5Final(digest,ctx)146 cvs_MD5Final (digest, ctx)
147 unsigned char digest[16];
148 struct cvs_MD5Context *ctx;
149 {
150 unsigned count;
151 unsigned char *p;
152
153 /* Compute number of bytes mod 64 */
154 count = (ctx->bits[0] >> 3) & 0x3F;
155
156 /* Set the first char of padding to 0x80. This is safe since there is
157 always at least one byte free */
158 p = ctx->in + count;
159 *p++ = 0x80;
160
161 /* Bytes of padding needed to make 64 bytes */
162 count = 64 - 1 - count;
163
164 /* Pad out to 56 mod 64 */
165 if (count < 8) {
166 /* Two lots of padding: Pad the first block to 64 bytes */
167 memset(p, 0, count);
168 cvs_MD5Transform (ctx->buf, ctx->in);
169
170 /* Now fill the next block with 56 bytes */
171 memset(ctx->in, 0, 56);
172 } else {
173 /* Pad block to 56 bytes */
174 memset(p, 0, count-8);
175 }
176
177 /* Append length in bits and transform */
178 putu32(ctx->bits[0], ctx->in + 56);
179 putu32(ctx->bits[1], ctx->in + 60);
180
181 cvs_MD5Transform (ctx->buf, ctx->in);
182 putu32(ctx->buf[0], digest);
183 putu32(ctx->buf[1], digest + 4);
184 putu32(ctx->buf[2], digest + 8);
185 putu32(ctx->buf[3], digest + 12);
186 memset(ctx, 0, sizeof(*ctx)); /* In case it's sensitive */
187 }
188
189 #ifndef ASM_MD5
190
191 /* The four core functions - F1 is optimized somewhat */
192
193 /* #define F1(x, y, z) (x & y | ~x & z) */
194 #define F1(x, y, z) (z ^ (x & (y ^ z)))
195 #define F2(x, y, z) F1(z, x, y)
196 #define F3(x, y, z) (x ^ y ^ z)
197 #define F4(x, y, z) (y ^ (x | ~z))
198
199 /* This is the central step in the MD5 algorithm. */
200 #define MD5STEP(f, w, x, y, z, data, s) \
201 ( w += f(x, y, z) + data, w &= 0xffffffff, w = w<<s | w>>(32-s), w += x )
202
203 /*
204 * The core of the MD5 algorithm, this alters an existing MD5 hash to
205 * reflect the addition of 16 longwords of new data. MD5Update blocks
206 * the data and converts bytes into longwords for this routine.
207 */
208 void
cvs_MD5Transform(buf,inraw)209 cvs_MD5Transform (buf, inraw)
210 cvs_uint32 buf[4];
211 const unsigned char inraw[64];
212 {
213 register cvs_uint32 a, b, c, d;
214 cvs_uint32 in[16];
215 int i;
216
217 for (i = 0; i < 16; ++i)
218 in[i] = getu32 (inraw + 4 * i);
219
220 a = buf[0];
221 b = buf[1];
222 c = buf[2];
223 d = buf[3];
224
225 MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478, 7);
226 MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
227 MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
228 MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
229 MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf, 7);
230 MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
231 MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
232 MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
233 MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8, 7);
234 MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
235 MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
236 MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
237 MD5STEP(F1, a, b, c, d, in[12]+0x6b901122, 7);
238 MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
239 MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
240 MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);
241
242 MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562, 5);
243 MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340, 9);
244 MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
245 MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
246 MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d, 5);
247 MD5STEP(F2, d, a, b, c, in[10]+0x02441453, 9);
248 MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
249 MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
250 MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6, 5);
251 MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6, 9);
252 MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
253 MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
254 MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905, 5);
255 MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8, 9);
256 MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
257 MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);
258
259 MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942, 4);
260 MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
261 MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
262 MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
263 MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44, 4);
264 MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
265 MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
266 MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
267 MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6, 4);
268 MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
269 MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
270 MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
271 MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039, 4);
272 MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
273 MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
274 MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);
275
276 MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244, 6);
277 MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
278 MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
279 MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
280 MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3, 6);
281 MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
282 MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
283 MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
284 MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f, 6);
285 MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
286 MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
287 MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
288 MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82, 6);
289 MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
290 MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
291 MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);
292
293 buf[0] += a;
294 buf[1] += b;
295 buf[2] += c;
296 buf[3] += d;
297 }
298 #endif
299
300 #ifdef TEST
301 /* Simple test program. Can use it to manually run the tests from
302 RFC1321 for example. */
303 #include <stdio.h>
304
305 int
main(int argc,char ** argv)306 main (int argc, char **argv)
307 {
308 struct cvs_MD5Context context;
309 unsigned char checksum[16];
310 int i;
311 int j;
312
313 if (argc < 2)
314 {
315 fprintf (stderr, "usage: %s string-to-hash\n", argv[0]);
316 exit (1);
317 }
318 for (j = 1; j < argc; ++j)
319 {
320 printf ("MD5 (\"%s\") = ", argv[j]);
321 cvs_MD5Init (&context);
322 cvs_MD5Update (&context, argv[j], strlen (argv[j]));
323 cvs_MD5Final (checksum, &context);
324 for (i = 0; i < 16; i++)
325 {
326 printf ("%02x", (unsigned int) checksum[i]);
327 }
328 printf ("\n");
329 }
330 return 0;
331 }
332 #endif /* TEST */
333