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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 #include <sys/types.h>
27
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31
32 #include "md5.h"
33
34 /* Little-endian byte-swapping routines. Note that these do not
35 depend on the size of datatypes such as uint32, nor do they require
36 us to detect the endianness of the machine we are running on. It
37 is possible they should be macros for speed, but I would be
38 surprised if they were a performance bottleneck for MD5. */
39
40 static uint32
41 getu32 (addr)
42 const unsigned char *addr;
43 {
44 return (((((unsigned long)addr[3] << 8) | addr[2]) << 8)
45 | addr[1]) << 8 | addr[0];
46 }
47
48 static void
49 putu32 (data, addr)
50 uint32 data;
51 unsigned char *addr;
52 {
53 addr[0] = (unsigned char)data;
54 addr[1] = (unsigned char)(data >> 8);
55 addr[2] = (unsigned char)(data >> 16);
56 addr[3] = (unsigned char)(data >> 24);
57 }
58
59 /*
60 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
61 * initialization constants.
62 */
63 void
64 MD5Init(ctx)
65 struct MD5Context *ctx;
66 {
67 ctx->buf[0] = 0x67452301;
68 ctx->buf[1] = 0xefcdab89;
69 ctx->buf[2] = 0x98badcfe;
70 ctx->buf[3] = 0x10325476;
71
72 ctx->bits[0] = 0;
73 ctx->bits[1] = 0;
74 }
75
76 /*
77 * Update context to reflect the concatenation of another buffer full
78 * of bytes.
79 */
80 void
81 MD5Update(ctx, buf, len)
82 struct MD5Context *ctx;
83 unsigned char const *buf;
84 unsigned len;
85 {
86 uint32 t;
87
88 /* Update bitcount */
89
90 t = ctx->bits[0];
91 if ((ctx->bits[0] = (t + ((uint32)len << 3)) & 0xffffffff) < t)
92 ctx->bits[1]++; /* Carry from low to high */
93 ctx->bits[1] += len >> 29;
94
95 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
96
97 /* Handle any leading odd-sized chunks */
98
99 if ( t ) {
100 unsigned char *p = ctx->in + t;
101
102 t = 64-t;
103 if (len < t) {
104 memcpy(p, buf, len);
105 return;
106 }
107 memcpy(p, buf, t);
108 MD5Transform(ctx->buf, ctx->in);
109 buf += t;
110 len -= t;
111 }
112
113 /* Process data in 64-byte chunks */
114
115 while (len >= 64) {
116 memcpy(ctx->in, buf, 64);
117 MD5Transform(ctx->buf, ctx->in);
118 buf += 64;
119 len -= 64;
120 }
121
122 /* Handle any remaining bytes of data. */
123
124 memcpy(ctx->in, buf, len);
125 }
126
127 /*
128 * Final wrapup - pad to 64-byte boundary with the bit pattern
129 * 1 0* (64-bit count of bits processed, MSB-first)
130 */
131 void
132 MD5Final(digest, ctx)
133 unsigned char digest[16];
134 struct MD5Context *ctx;
135 {
136 unsigned count;
137 unsigned char *p;
138
139 /* Compute number of bytes mod 64 */
140 count = (ctx->bits[0] >> 3) & 0x3F;
141
142 /* Set the first char of padding to 0x80. This is safe since there is
143 always at least one byte free */
144 p = ctx->in + count;
145 *p++ = 0x80;
146
147 /* Bytes of padding needed to make 64 bytes */
148 count = 64 - 1 - count;
149
150 /* Pad out to 56 mod 64 */
151 if (count < 8) {
152 /* Two lots of padding: Pad the first block to 64 bytes */
153 memset(p, 0, count);
154 MD5Transform(ctx->buf, ctx->in);
155
156 /* Now fill the next block with 56 bytes */
157 memset(ctx->in, 0, 56);
158 } else {
159 /* Pad block to 56 bytes */
160 memset(p, 0, count-8);
161 }
162
163 /* Append length in bits and transform */
164 putu32(ctx->bits[0], ctx->in + 56);
165 putu32(ctx->bits[1], ctx->in + 60);
166
167 MD5Transform(ctx->buf, ctx->in);
168 putu32(ctx->buf[0], digest);
169 putu32(ctx->buf[1], digest + 4);
170 putu32(ctx->buf[2], digest + 8);
171 putu32(ctx->buf[3], digest + 12);
172 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
173 }
174
175 #ifndef ASM_MD5
176
177 /* The four core functions - F1 is optimized somewhat */
178
179 /* #define F1(x, y, z) (x & y | ~x & z) */
180 #define F1(x, y, z) (z ^ (x & (y ^ z)))
181 #define F2(x, y, z) F1(z, x, y)
182 #define F3(x, y, z) (x ^ y ^ z)
183 #define F4(x, y, z) (y ^ (x | ~z))
184
185 /* This is the central step in the MD5 algorithm. */
186 #define MD5STEP(f, w, x, y, z, data, s) \
187 ( w += f(x, y, z) + data, w &= 0xffffffff, w = w<<s | w>>(32-s), w += x )
188
189 /*
190 * The core of the MD5 algorithm, this alters an existing MD5 hash to
191 * reflect the addition of 16 longwords of new data. MD5Update blocks
192 * the data and converts bytes into longwords for this routine.
193 */
194 void
195 MD5Transform(buf, inraw)
196 uint32 buf[4];
197 const unsigned char inraw[64];
198 {
199 register uint32 a, b, c, d;
200 uint32 in[16];
201 int i;
202
203 for (i = 0; i < 16; ++i)
204 in[i] = getu32 (inraw + 4 * i);
205
206 a = buf[0];
207 b = buf[1];
208 c = buf[2];
209 d = buf[3];
210
211 MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478, 7);
212 MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
213 MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
214 MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
215 MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf, 7);
216 MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
217 MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
218 MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
219 MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8, 7);
220 MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
221 MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
222 MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
223 MD5STEP(F1, a, b, c, d, in[12]+0x6b901122, 7);
224 MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
225 MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
226 MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);
227
228 MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562, 5);
229 MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340, 9);
230 MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
231 MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
232 MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d, 5);
233 MD5STEP(F2, d, a, b, c, in[10]+0x02441453, 9);
234 MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
235 MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
236 MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6, 5);
237 MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6, 9);
238 MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
239 MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
240 MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905, 5);
241 MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8, 9);
242 MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
243 MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);
244
245 MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942, 4);
246 MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
247 MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
248 MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
249 MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44, 4);
250 MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
251 MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
252 MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
253 MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6, 4);
254 MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
255 MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
256 MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
257 MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039, 4);
258 MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
259 MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
260 MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);
261
262 MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244, 6);
263 MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
264 MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
265 MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
266 MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3, 6);
267 MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
268 MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
269 MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
270 MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f, 6);
271 MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
272 MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
273 MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
274 MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82, 6);
275 MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
276 MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
277 MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);
278
279 buf[0] += a;
280 buf[1] += b;
281 buf[2] += c;
282 buf[3] += d;
283 }
284 #endif
285
286 #ifdef TEST
287 /* Simple test program. Can use it to manually run the tests from
288 RFC1321 for example. */
289 #include <stdio.h>
290
291 int
292 main (int argc, char **argv)
293 {
294 struct MD5Context context;
295 unsigned char checksum[16];
296 int i;
297 int j;
298
299 if (argc < 2)
300 {
301 fprintf (stderr, "usage: %s string-to-hash\n", argv[0]);
302 exit (1);
303 }
304 for (j = 1; j < argc; ++j)
305 {
306 printf ("MD5 (\"%s\") = ", argv[j]);
307 MD5Init (&context);
308 MD5Update (&context, argv[j], strlen (argv[j]));
309 MD5Final (checksum, &context);
310 for (i = 0; i < 16; i++)
311 {
312 printf ("%02x", (unsigned int) checksum[i]);
313 }
314 printf ("\n");
315 }
316 return 0;
317 }
318 #endif /* TEST */