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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 #include "config.h"
19
20 #if HAVE_STRING_H || STDC_HEADERS
21 #include <string.h> /* for memcpy() */
22 #endif
23
24 /* Add prototype support. */
25 #ifndef PROTO
26 #if defined (USE_PROTOTYPES) ? USE_PROTOTYPES : defined (__STDC__)
27 #define PROTO(ARGS) ARGS
28 #else
29 #define PROTO(ARGS) ()
30 #endif
31 #endif
32
33 #include "md5.h"
34
35 void byteReverse PROTO ((unsigned char *buf, unsigned longs));
36
37 #ifndef ASM_MD5
38 /*
39 * Note: this code is harmless on little-endian machines.
40 */
41 void byteReverse (buf, longs)
42 unsigned char *buf;
43 unsigned longs;
44 {
45 uint32 t;
46 do {
47 t = (uint32)((unsigned)buf[3]<<8 | buf[2]) << 16 |
48 ((unsigned)buf[1]<<8 | buf[0]);
49 *(uint32 *)buf = t;
50 buf += 4;
51 } while (--longs);
52 }
53 #endif
54
55 /*
56 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
57 * initialization constants.
58 */
59 void
60 MD5Init(ctx)
61 struct MD5Context *ctx;
62 {
63 ctx->buf[0] = 0x67452301;
64 ctx->buf[1] = 0xefcdab89;
65 ctx->buf[2] = 0x98badcfe;
66 ctx->buf[3] = 0x10325476;
67
68 ctx->bits[0] = 0;
69 ctx->bits[1] = 0;
70 }
71
72 /*
73 * Update context to reflect the concatenation of another buffer full
74 * of bytes.
75 */
76 void
77 MD5Update(ctx, buf, len)
78 struct MD5Context *ctx;
79 unsigned char const *buf;
80 unsigned len;
81 {
82 uint32 t;
83
84 /* Update bitcount */
85
86 t = ctx->bits[0];
87 if ((ctx->bits[0] = t + ((uint32)len << 3)) < t)
88 ctx->bits[1]++; /* Carry from low to high */
89 ctx->bits[1] += len >> 29;
90
91 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
92
93 /* Handle any leading odd-sized chunks */
94
95 if ( t ) {
96 unsigned char *p = (unsigned char *)ctx->in + t;
97
98 t = 64-t;
99 if (len < t) {
100 memcpy(p, buf, len);
101 return;
102 }
103 memcpy(p, buf, t);
104 byteReverse(ctx->in, 16);
105 MD5Transform(ctx->buf, (uint32 *)ctx->in);
106 buf += t;
107 len -= t;
108 }
109
110 /* Process data in 64-byte chunks */
111
112 while (len >= 64) {
113 memcpy(ctx->in, buf, 64);
114 byteReverse(ctx->in, 16);
115 MD5Transform(ctx->buf, (uint32 *)ctx->in);
116 buf += 64;
117 len -= 64;
118 }
119
120 /* Handle any remaining bytes of data. */
121
122 memcpy(ctx->in, buf, len);
123 }
124
125 /*
126 * Final wrapup - pad to 64-byte boundary with the bit pattern
127 * 1 0* (64-bit count of bits processed, MSB-first)
128 */
129 void
130 MD5Final(digest, ctx)
131 unsigned char digest[16];
132 struct MD5Context *ctx;
133 {
134 unsigned count;
135 unsigned char *p;
136
137 /* Compute number of bytes mod 64 */
138 count = (ctx->bits[0] >> 3) & 0x3F;
139
140 /* Set the first char of padding to 0x80. This is safe since there is
141 always at least one byte free */
142 p = ctx->in + count;
143 *p++ = 0x80;
144
145 /* Bytes of padding needed to make 64 bytes */
146 count = 64 - 1 - count;
147
148 /* Pad out to 56 mod 64 */
149 if (count < 8) {
150 /* Two lots of padding: Pad the first block to 64 bytes */
151 memset(p, 0, count);
152 byteReverse(ctx->in, 16);
153 MD5Transform(ctx->buf, (uint32 *)ctx->in);
154
155 /* Now fill the next block with 56 bytes */
156 memset(ctx->in, 0, 56);
157 } else {
158 /* Pad block to 56 bytes */
159 memset(p, 0, count-8);
160 }
161 byteReverse(ctx->in, 14);
162
163 /* Append length in bits and transform */
164 ((uint32 *)ctx->in)[ 14 ] = ctx->bits[0];
165 ((uint32 *)ctx->in)[ 15 ] = ctx->bits[1];
166
167 MD5Transform(ctx->buf, (uint32 *)ctx->in);
168 byteReverse((unsigned char *)ctx->buf, 4);
169 memcpy(digest, ctx->buf, 16);
170 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
171 }
172
173 #ifndef ASM_MD5
174
175 /* The four core functions - F1 is optimized somewhat */
176
177 /* #define F1(x, y, z) (x & y | ~x & z) */
178 #define F1(x, y, z) (z ^ (x & (y ^ z)))
179 #define F2(x, y, z) F1(z, x, y)
180 #define F3(x, y, z) (x ^ y ^ z)
181 #define F4(x, y, z) (y ^ (x | ~z))
182
183 /* This is the central step in the MD5 algorithm. */
184 #define MD5STEP(f, w, x, y, z, data, s) \
185 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
186
187 /*
188 * The core of the MD5 algorithm, this alters an existing MD5 hash to
189 * reflect the addition of 16 longwords of new data. MD5Update blocks
190 * the data and converts bytes into longwords for this routine.
191 */
192 void
193 MD5Transform(buf, in)
194 uint32 buf[4];
195 uint32 const in[16];
196 {
197 register uint32 a, b, c, d;
198
199 a = buf[0];
200 b = buf[1];
201 c = buf[2];
202 d = buf[3];
203
204 MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478, 7);
205 MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
206 MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
207 MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
208 MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf, 7);
209 MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
210 MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
211 MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
212 MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8, 7);
213 MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
214 MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
215 MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
216 MD5STEP(F1, a, b, c, d, in[12]+0x6b901122, 7);
217 MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
218 MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
219 MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);
220
221 MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562, 5);
222 MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340, 9);
223 MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
224 MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
225 MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d, 5);
226 MD5STEP(F2, d, a, b, c, in[10]+0x02441453, 9);
227 MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
228 MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
229 MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6, 5);
230 MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6, 9);
231 MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
232 MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
233 MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905, 5);
234 MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8, 9);
235 MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
236 MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);
237
238 MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942, 4);
239 MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
240 MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
241 MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
242 MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44, 4);
243 MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
244 MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
245 MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
246 MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6, 4);
247 MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
248 MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
249 MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
250 MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039, 4);
251 MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
252 MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
253 MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);
254
255 MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244, 6);
256 MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
257 MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
258 MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
259 MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3, 6);
260 MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
261 MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
262 MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
263 MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f, 6);
264 MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
265 MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
266 MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
267 MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82, 6);
268 MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
269 MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
270 MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);
271
272 buf[0] += a;
273 buf[1] += b;
274 buf[2] += c;
275 buf[3] += d;
276 }
277 #endif