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18c8241a MM |
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 | /* | |
19 | * Adapted for BIRD by Martin Mares <mj@atrey.karlin.mff.cuni.cz> | |
20 | */ | |
21 | ||
18c8241a | 22 | #include "nest/bird.h" |
221135d6 | 23 | #include "lib/string.h" |
18c8241a MM |
24 | #include "md5.h" |
25 | ||
26 | #ifdef CPU_LITTLE_ENDIAN | |
27 | #define byteReverse(buf, len) /* Nothing */ | |
28 | #else | |
29 | void byteReverse(unsigned char *buf, unsigned longs); | |
30 | ||
31 | /* | |
32 | * Note: this code is harmless on little-endian machines. | |
33 | */ | |
34 | void byteReverse(unsigned char *buf, unsigned longs) | |
35 | { | |
36 | u32 t; | |
37 | do { | |
38 | t = (u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 | | |
39 | ((unsigned) buf[1] << 8 | buf[0]); | |
40 | *(u32 *) buf = t; | |
41 | buf += 4; | |
42 | } while (--longs); | |
43 | } | |
44 | #endif | |
45 | ||
46 | /* | |
47 | * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious | |
48 | * initialization constants. | |
49 | */ | |
50 | void MD5Init(struct MD5Context *ctx) | |
51 | { | |
52 | ctx->buf[0] = 0x67452301; | |
53 | ctx->buf[1] = 0xefcdab89; | |
54 | ctx->buf[2] = 0x98badcfe; | |
55 | ctx->buf[3] = 0x10325476; | |
56 | ||
57 | ctx->bits[0] = 0; | |
58 | ctx->bits[1] = 0; | |
59 | } | |
60 | ||
61 | /* | |
62 | * Update context to reflect the concatenation of another buffer full | |
63 | * of bytes. | |
64 | */ | |
65 | void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len) | |
66 | { | |
67 | u32 t; | |
68 | ||
69 | /* Update bitcount */ | |
70 | ||
71 | t = ctx->bits[0]; | |
72 | if ((ctx->bits[0] = t + ((u32) len << 3)) < t) | |
73 | ctx->bits[1]++; /* Carry from low to high */ | |
74 | ctx->bits[1] += len >> 29; | |
75 | ||
76 | t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */ | |
77 | ||
78 | /* Handle any leading odd-sized chunks */ | |
79 | ||
80 | if (t) { | |
81 | unsigned char *p = (unsigned char *) ctx->in + t; | |
82 | ||
83 | t = 64 - t; | |
84 | if (len < t) { | |
85 | memcpy(p, buf, len); | |
86 | return; | |
87 | } | |
88 | memcpy(p, buf, t); | |
89 | byteReverse(ctx->in, 16); | |
90 | MD5Transform(ctx->buf, (u32 *) ctx->in); | |
91 | buf += t; | |
92 | len -= t; | |
93 | } | |
94 | /* Process data in 64-byte chunks */ | |
95 | ||
96 | while (len >= 64) { | |
97 | memcpy(ctx->in, buf, 64); | |
98 | byteReverse(ctx->in, 16); | |
99 | MD5Transform(ctx->buf, (u32 *) ctx->in); | |
100 | buf += 64; | |
101 | len -= 64; | |
102 | } | |
103 | ||
104 | /* Handle any remaining bytes of data. */ | |
105 | ||
106 | memcpy(ctx->in, buf, len); | |
107 | } | |
108 | ||
109 | /* | |
110 | * Final wrapup - pad to 64-byte boundary with the bit pattern | |
111 | * 1 0* (64-bit count of bits processed, MSB-first) | |
112 | */ | |
113 | void MD5Final(unsigned char digest[16], struct MD5Context *ctx) | |
114 | { | |
115 | unsigned count; | |
116 | unsigned char *p; | |
117 | ||
118 | /* Compute number of bytes mod 64 */ | |
119 | count = (ctx->bits[0] >> 3) & 0x3F; | |
120 | ||
121 | /* Set the first char of padding to 0x80. This is safe since there is | |
122 | always at least one byte free */ | |
123 | p = ctx->in + count; | |
124 | *p++ = 0x80; | |
125 | ||
126 | /* Bytes of padding needed to make 64 bytes */ | |
127 | count = 64 - 1 - count; | |
128 | ||
129 | /* Pad out to 56 mod 64 */ | |
130 | if (count < 8) { | |
131 | /* Two lots of padding: Pad the first block to 64 bytes */ | |
132 | memset(p, 0, count); | |
133 | byteReverse(ctx->in, 16); | |
134 | MD5Transform(ctx->buf, (u32 *) ctx->in); | |
135 | ||
136 | /* Now fill the next block with 56 bytes */ | |
137 | memset(ctx->in, 0, 56); | |
138 | } else { | |
139 | /* Pad block to 56 bytes */ | |
140 | memset(p, 0, count - 8); | |
141 | } | |
142 | byteReverse(ctx->in, 14); | |
143 | ||
144 | /* Append length in bits and transform */ | |
145 | ((u32 *) ctx->in)[14] = ctx->bits[0]; | |
146 | ((u32 *) ctx->in)[15] = ctx->bits[1]; | |
147 | ||
148 | MD5Transform(ctx->buf, (u32 *) ctx->in); | |
149 | byteReverse((unsigned char *) ctx->buf, 4); | |
150 | memcpy(digest, ctx->buf, 16); | |
151 | memset((char *) ctx, 0, sizeof(ctx)); /* In case it's sensitive */ | |
152 | } | |
153 | ||
154 | /* The four core functions - F1 is optimized somewhat */ | |
155 | ||
156 | /* #define F1(x, y, z) (x & y | ~x & z) */ | |
157 | #define F1(x, y, z) (z ^ (x & (y ^ z))) | |
158 | #define F2(x, y, z) F1(z, x, y) | |
159 | #define F3(x, y, z) (x ^ y ^ z) | |
160 | #define F4(x, y, z) (y ^ (x | ~z)) | |
161 | ||
162 | /* This is the central step in the MD5 algorithm. */ | |
163 | #define MD5STEP(f, w, x, y, z, data, s) \ | |
164 | ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x ) | |
165 | ||
166 | /* | |
167 | * The core of the MD5 algorithm, this alters an existing MD5 hash to | |
168 | * reflect the addition of 16 longwords of new data. MD5Update blocks | |
169 | * the data and converts bytes into longwords for this routine. | |
170 | */ | |
171 | void MD5Transform(u32 buf[4], u32 const in[16]) | |
172 | { | |
173 | register u32 a, b, c, d; | |
174 | ||
175 | a = buf[0]; | |
176 | b = buf[1]; | |
177 | c = buf[2]; | |
178 | d = buf[3]; | |
179 | ||
180 | MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); | |
181 | MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); | |
182 | MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); | |
183 | MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); | |
184 | MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); | |
185 | MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); | |
186 | MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); | |
187 | MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); | |
188 | MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); | |
189 | MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); | |
190 | MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); | |
191 | MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); | |
192 | MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); | |
193 | MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); | |
194 | MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); | |
195 | MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); | |
196 | ||
197 | MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); | |
198 | MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); | |
199 | MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); | |
200 | MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); | |
201 | MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); | |
202 | MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); | |
203 | MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); | |
204 | MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); | |
205 | MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); | |
206 | MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); | |
207 | MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); | |
208 | MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); | |
209 | MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); | |
210 | MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); | |
211 | MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); | |
212 | MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); | |
213 | ||
214 | MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); | |
215 | MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); | |
216 | MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); | |
217 | MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); | |
218 | MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); | |
219 | MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); | |
220 | MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); | |
221 | MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); | |
222 | MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); | |
223 | MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); | |
224 | MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); | |
225 | MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); | |
226 | MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); | |
227 | MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); | |
228 | MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); | |
229 | MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); | |
230 | ||
231 | MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); | |
232 | MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); | |
233 | MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); | |
234 | MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); | |
235 | MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); | |
236 | MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); | |
237 | MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); | |
238 | MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); | |
239 | MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); | |
240 | MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); | |
241 | MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); | |
242 | MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); | |
243 | MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); | |
244 | MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); | |
245 | MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); | |
246 | MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); | |
247 | ||
248 | buf[0] += a; | |
249 | buf[1] += b; | |
250 | buf[2] += c; | |
251 | buf[3] += d; | |
252 | } |