Line data Source code
1 : /* $OpenBSD: md5.c,v 1.4 2014/12/28 10:04:35 tedu Exp $ */
2 :
3 : /*
4 : * This code implements the MD5 message-digest algorithm.
5 : * The algorithm is due to Ron Rivest. This code was
6 : * written by Colin Plumb in 1993, no copyright is claimed.
7 : * This code is in the public domain; do with it what you wish.
8 : *
9 : * Equivalent code is available from RSA Data Security, Inc.
10 : * This code has been tested against that, and is equivalent,
11 : * except that you don't need to include two pages of legalese
12 : * with every copy.
13 : *
14 : * To compute the message digest of a chunk of bytes, declare an
15 : * MD5Context structure, pass it to MD5Init, call MD5Update as
16 : * needed on buffers full of bytes, and then call MD5Final, which
17 : * will fill a supplied 16-byte array with the digest.
18 : */
19 :
20 : #include <sys/param.h>
21 : #include <sys/systm.h>
22 : #include <crypto/md5.h>
23 :
24 : #define PUT_64BIT_LE(cp, value) do { \
25 : (cp)[7] = (value) >> 56; \
26 : (cp)[6] = (value) >> 48; \
27 : (cp)[5] = (value) >> 40; \
28 : (cp)[4] = (value) >> 32; \
29 : (cp)[3] = (value) >> 24; \
30 : (cp)[2] = (value) >> 16; \
31 : (cp)[1] = (value) >> 8; \
32 : (cp)[0] = (value); } while (0)
33 :
34 : #define PUT_32BIT_LE(cp, value) do { \
35 : (cp)[3] = (value) >> 24; \
36 : (cp)[2] = (value) >> 16; \
37 : (cp)[1] = (value) >> 8; \
38 : (cp)[0] = (value); } while (0)
39 :
40 : static u_int8_t PADDING[MD5_BLOCK_LENGTH] = {
41 : 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
42 : 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
43 : 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
44 : };
45 :
46 : /*
47 : * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
48 : * initialization constants.
49 : */
50 : void
51 0 : MD5Init(MD5_CTX *ctx)
52 : {
53 0 : ctx->count = 0;
54 0 : ctx->state[0] = 0x67452301;
55 0 : ctx->state[1] = 0xefcdab89;
56 0 : ctx->state[2] = 0x98badcfe;
57 0 : ctx->state[3] = 0x10325476;
58 0 : }
59 :
60 : /*
61 : * Update context to reflect the concatenation of another buffer full
62 : * of bytes.
63 : */
64 : void
65 0 : MD5Update(MD5_CTX *ctx, const void *inputptr, size_t len)
66 : {
67 : const uint8_t *input = inputptr;
68 : size_t have, need;
69 :
70 : /* Check how many bytes we already have and how many more we need. */
71 0 : have = (size_t)((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
72 0 : need = MD5_BLOCK_LENGTH - have;
73 :
74 : /* Update bitcount */
75 0 : ctx->count += (u_int64_t)len << 3;
76 :
77 0 : if (len >= need) {
78 0 : if (have != 0) {
79 0 : memcpy(ctx->buffer + have, input, need);
80 0 : MD5Transform(ctx->state, ctx->buffer);
81 0 : input += need;
82 0 : len -= need;
83 : have = 0;
84 0 : }
85 :
86 : /* Process data in MD5_BLOCK_LENGTH-byte chunks. */
87 0 : while (len >= MD5_BLOCK_LENGTH) {
88 0 : MD5Transform(ctx->state, input);
89 0 : input += MD5_BLOCK_LENGTH;
90 0 : len -= MD5_BLOCK_LENGTH;
91 : }
92 : }
93 :
94 : /* Handle any remaining bytes of data. */
95 0 : if (len != 0)
96 0 : memcpy(ctx->buffer + have, input, len);
97 0 : }
98 :
99 : /*
100 : * Final wrapup - pad to 64-byte boundary with the bit pattern
101 : * 1 0* (64-bit count of bits processed, MSB-first)
102 : */
103 : void
104 0 : MD5Final(unsigned char digest[MD5_DIGEST_LENGTH], MD5_CTX *ctx)
105 : {
106 0 : u_int8_t count[8];
107 : size_t padlen;
108 : int i;
109 :
110 : /* Convert count to 8 bytes in little endian order. */
111 0 : PUT_64BIT_LE(count, ctx->count);
112 :
113 : /* Pad out to 56 mod 64. */
114 0 : padlen = MD5_BLOCK_LENGTH -
115 0 : ((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
116 0 : if (padlen < 1 + 8)
117 0 : padlen += MD5_BLOCK_LENGTH;
118 0 : MD5Update(ctx, PADDING, padlen - 8); /* padlen - 8 <= 64 */
119 0 : MD5Update(ctx, count, 8);
120 :
121 0 : for (i = 0; i < 4; i++)
122 0 : PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
123 0 : explicit_bzero(ctx, sizeof(*ctx)); /* in case it's sensitive */
124 0 : }
125 :
126 :
127 : /* The four core functions - F1 is optimized somewhat */
128 :
129 : /* #define F1(x, y, z) (x & y | ~x & z) */
130 : #define F1(x, y, z) (z ^ (x & (y ^ z)))
131 : #define F2(x, y, z) F1(z, x, y)
132 : #define F3(x, y, z) (x ^ y ^ z)
133 : #define F4(x, y, z) (y ^ (x | ~z))
134 :
135 : /* This is the central step in the MD5 algorithm. */
136 : #define MD5STEP(f, w, x, y, z, data, s) \
137 : ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
138 :
139 : /*
140 : * The core of the MD5 algorithm, this alters an existing MD5 hash to
141 : * reflect the addition of 16 longwords of new data. MD5Update blocks
142 : * the data and converts bytes into longwords for this routine.
143 : */
144 : void
145 0 : MD5Transform(u_int32_t state[4], const u_int8_t block[MD5_BLOCK_LENGTH])
146 : {
147 : u_int32_t a, b, c, d, in[MD5_BLOCK_LENGTH / 4];
148 :
149 : #if BYTE_ORDER == LITTLE_ENDIAN
150 0 : memcpy(in, block, sizeof(in));
151 : #else
152 : for (a = 0; a < MD5_BLOCK_LENGTH / 4; a++) {
153 : in[a] = (u_int32_t)(
154 : (u_int32_t)(block[a * 4 + 0]) |
155 : (u_int32_t)(block[a * 4 + 1]) << 8 |
156 : (u_int32_t)(block[a * 4 + 2]) << 16 |
157 : (u_int32_t)(block[a * 4 + 3]) << 24);
158 : }
159 : #endif
160 :
161 0 : a = state[0];
162 0 : b = state[1];
163 0 : c = state[2];
164 0 : d = state[3];
165 :
166 0 : MD5STEP(F1, a, b, c, d, in[ 0] + 0xd76aa478, 7);
167 0 : MD5STEP(F1, d, a, b, c, in[ 1] + 0xe8c7b756, 12);
168 0 : MD5STEP(F1, c, d, a, b, in[ 2] + 0x242070db, 17);
169 0 : MD5STEP(F1, b, c, d, a, in[ 3] + 0xc1bdceee, 22);
170 0 : MD5STEP(F1, a, b, c, d, in[ 4] + 0xf57c0faf, 7);
171 0 : MD5STEP(F1, d, a, b, c, in[ 5] + 0x4787c62a, 12);
172 0 : MD5STEP(F1, c, d, a, b, in[ 6] + 0xa8304613, 17);
173 0 : MD5STEP(F1, b, c, d, a, in[ 7] + 0xfd469501, 22);
174 0 : MD5STEP(F1, a, b, c, d, in[ 8] + 0x698098d8, 7);
175 0 : MD5STEP(F1, d, a, b, c, in[ 9] + 0x8b44f7af, 12);
176 0 : MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
177 0 : MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
178 0 : MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
179 0 : MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
180 0 : MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
181 0 : MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
182 :
183 0 : MD5STEP(F2, a, b, c, d, in[ 1] + 0xf61e2562, 5);
184 0 : MD5STEP(F2, d, a, b, c, in[ 6] + 0xc040b340, 9);
185 0 : MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
186 0 : MD5STEP(F2, b, c, d, a, in[ 0] + 0xe9b6c7aa, 20);
187 0 : MD5STEP(F2, a, b, c, d, in[ 5] + 0xd62f105d, 5);
188 0 : MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
189 0 : MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
190 0 : MD5STEP(F2, b, c, d, a, in[ 4] + 0xe7d3fbc8, 20);
191 0 : MD5STEP(F2, a, b, c, d, in[ 9] + 0x21e1cde6, 5);
192 0 : MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
193 0 : MD5STEP(F2, c, d, a, b, in[ 3] + 0xf4d50d87, 14);
194 0 : MD5STEP(F2, b, c, d, a, in[ 8] + 0x455a14ed, 20);
195 0 : MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
196 0 : MD5STEP(F2, d, a, b, c, in[ 2] + 0xfcefa3f8, 9);
197 0 : MD5STEP(F2, c, d, a, b, in[ 7] + 0x676f02d9, 14);
198 0 : MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
199 :
200 0 : MD5STEP(F3, a, b, c, d, in[ 5] + 0xfffa3942, 4);
201 0 : MD5STEP(F3, d, a, b, c, in[ 8] + 0x8771f681, 11);
202 0 : MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
203 0 : MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
204 0 : MD5STEP(F3, a, b, c, d, in[ 1] + 0xa4beea44, 4);
205 0 : MD5STEP(F3, d, a, b, c, in[ 4] + 0x4bdecfa9, 11);
206 0 : MD5STEP(F3, c, d, a, b, in[ 7] + 0xf6bb4b60, 16);
207 0 : MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
208 0 : MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
209 0 : MD5STEP(F3, d, a, b, c, in[ 0] + 0xeaa127fa, 11);
210 0 : MD5STEP(F3, c, d, a, b, in[ 3] + 0xd4ef3085, 16);
211 0 : MD5STEP(F3, b, c, d, a, in[ 6] + 0x04881d05, 23);
212 0 : MD5STEP(F3, a, b, c, d, in[ 9] + 0xd9d4d039, 4);
213 0 : MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
214 0 : MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
215 0 : MD5STEP(F3, b, c, d, a, in[2 ] + 0xc4ac5665, 23);
216 :
217 0 : MD5STEP(F4, a, b, c, d, in[ 0] + 0xf4292244, 6);
218 0 : MD5STEP(F4, d, a, b, c, in[7 ] + 0x432aff97, 10);
219 0 : MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
220 0 : MD5STEP(F4, b, c, d, a, in[5 ] + 0xfc93a039, 21);
221 0 : MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
222 0 : MD5STEP(F4, d, a, b, c, in[3 ] + 0x8f0ccc92, 10);
223 0 : MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
224 0 : MD5STEP(F4, b, c, d, a, in[1 ] + 0x85845dd1, 21);
225 0 : MD5STEP(F4, a, b, c, d, in[8 ] + 0x6fa87e4f, 6);
226 0 : MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
227 0 : MD5STEP(F4, c, d, a, b, in[6 ] + 0xa3014314, 15);
228 0 : MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
229 0 : MD5STEP(F4, a, b, c, d, in[4 ] + 0xf7537e82, 6);
230 0 : MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
231 0 : MD5STEP(F4, c, d, a, b, in[2 ] + 0x2ad7d2bb, 15);
232 0 : MD5STEP(F4, b, c, d, a, in[9 ] + 0xeb86d391, 21);
233 :
234 0 : state[0] += a;
235 0 : state[1] += b;
236 0 : state[2] += c;
237 0 : state[3] += d;
238 0 : }
|
