Annotation of sys/crypto/md5.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: md5.c,v 1.1 2004/05/07 14:42:26 millert 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: MD5Init(MD5_CTX *ctx)
52: {
53: ctx->count = 0;
54: ctx->state[0] = 0x67452301;
55: ctx->state[1] = 0xefcdab89;
56: ctx->state[2] = 0x98badcfe;
57: ctx->state[3] = 0x10325476;
58: }
59:
60: /*
61: * Update context to reflect the concatenation of another buffer full
62: * of bytes.
63: */
64: void
65: MD5Update(MD5_CTX *ctx, const unsigned char *input, size_t len)
66: {
67: size_t have, need;
68:
69: /* Check how many bytes we already have and how many more we need. */
70: have = (size_t)((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
71: need = MD5_BLOCK_LENGTH - have;
72:
73: /* Update bitcount */
74: ctx->count += (u_int64_t)len << 3;
75:
76: if (len >= need) {
77: if (have != 0) {
78: bcopy(input, ctx->buffer + have, need);
79: MD5Transform(ctx->state, ctx->buffer);
80: input += need;
81: len -= need;
82: have = 0;
83: }
84:
85: /* Process data in MD5_BLOCK_LENGTH-byte chunks. */
86: while (len >= MD5_BLOCK_LENGTH) {
87: MD5Transform(ctx->state, input);
88: input += MD5_BLOCK_LENGTH;
89: len -= MD5_BLOCK_LENGTH;
90: }
91: }
92:
93: /* Handle any remaining bytes of data. */
94: if (len != 0)
95: bcopy(input, ctx->buffer + have, len);
96: }
97:
98: /*
99: * Final wrapup - pad to 64-byte boundary with the bit pattern
100: * 1 0* (64-bit count of bits processed, MSB-first)
101: */
102: void
103: MD5Final(unsigned char digest[MD5_DIGEST_LENGTH], MD5_CTX *ctx)
104: {
105: u_int8_t count[8];
106: size_t padlen;
107: int i;
108:
109: /* Convert count to 8 bytes in little endian order. */
110: PUT_64BIT_LE(count, ctx->count);
111:
112: /* Pad out to 56 mod 64. */
113: padlen = MD5_BLOCK_LENGTH -
114: ((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
115: if (padlen < 1 + 8)
116: padlen += MD5_BLOCK_LENGTH;
117: MD5Update(ctx, PADDING, padlen - 8); /* padlen - 8 <= 64 */
118: MD5Update(ctx, count, 8);
119:
120: if (digest != NULL) {
121: for (i = 0; i < 4; i++)
122: PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
123: }
124: bzero(ctx, sizeof(*ctx)); /* in case it's sensitive */
125: }
126:
127:
128: /* The four core functions - F1 is optimized somewhat */
129:
130: /* #define F1(x, y, z) (x & y | ~x & z) */
131: #define F1(x, y, z) (z ^ (x & (y ^ z)))
132: #define F2(x, y, z) F1(z, x, y)
133: #define F3(x, y, z) (x ^ y ^ z)
134: #define F4(x, y, z) (y ^ (x | ~z))
135:
136: /* This is the central step in the MD5 algorithm. */
137: #define MD5STEP(f, w, x, y, z, data, s) \
138: ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
139:
140: /*
141: * The core of the MD5 algorithm, this alters an existing MD5 hash to
142: * reflect the addition of 16 longwords of new data. MD5Update blocks
143: * the data and converts bytes into longwords for this routine.
144: */
145: void
146: MD5Transform(u_int32_t state[4], const u_int8_t block[MD5_BLOCK_LENGTH])
147: {
148: u_int32_t a, b, c, d, in[MD5_BLOCK_LENGTH / 4];
149:
150: #if BYTE_ORDER == LITTLE_ENDIAN
151: bcopy(block, in, sizeof(in));
152: #else
153: for (a = 0; a < MD5_BLOCK_LENGTH / 4; a++) {
154: in[a] = (u_int32_t)(
155: (u_int32_t)(block[a * 4 + 0]) |
156: (u_int32_t)(block[a * 4 + 1]) << 8 |
157: (u_int32_t)(block[a * 4 + 2]) << 16 |
158: (u_int32_t)(block[a * 4 + 3]) << 24);
159: }
160: #endif
161:
162: a = state[0];
163: b = state[1];
164: c = state[2];
165: d = state[3];
166:
167: MD5STEP(F1, a, b, c, d, in[ 0] + 0xd76aa478, 7);
168: MD5STEP(F1, d, a, b, c, in[ 1] + 0xe8c7b756, 12);
169: MD5STEP(F1, c, d, a, b, in[ 2] + 0x242070db, 17);
170: MD5STEP(F1, b, c, d, a, in[ 3] + 0xc1bdceee, 22);
171: MD5STEP(F1, a, b, c, d, in[ 4] + 0xf57c0faf, 7);
172: MD5STEP(F1, d, a, b, c, in[ 5] + 0x4787c62a, 12);
173: MD5STEP(F1, c, d, a, b, in[ 6] + 0xa8304613, 17);
174: MD5STEP(F1, b, c, d, a, in[ 7] + 0xfd469501, 22);
175: MD5STEP(F1, a, b, c, d, in[ 8] + 0x698098d8, 7);
176: MD5STEP(F1, d, a, b, c, in[ 9] + 0x8b44f7af, 12);
177: MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
178: MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
179: MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
180: MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
181: MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
182: MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
183:
184: MD5STEP(F2, a, b, c, d, in[ 1] + 0xf61e2562, 5);
185: MD5STEP(F2, d, a, b, c, in[ 6] + 0xc040b340, 9);
186: MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
187: MD5STEP(F2, b, c, d, a, in[ 0] + 0xe9b6c7aa, 20);
188: MD5STEP(F2, a, b, c, d, in[ 5] + 0xd62f105d, 5);
189: MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
190: MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
191: MD5STEP(F2, b, c, d, a, in[ 4] + 0xe7d3fbc8, 20);
192: MD5STEP(F2, a, b, c, d, in[ 9] + 0x21e1cde6, 5);
193: MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
194: MD5STEP(F2, c, d, a, b, in[ 3] + 0xf4d50d87, 14);
195: MD5STEP(F2, b, c, d, a, in[ 8] + 0x455a14ed, 20);
196: MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
197: MD5STEP(F2, d, a, b, c, in[ 2] + 0xfcefa3f8, 9);
198: MD5STEP(F2, c, d, a, b, in[ 7] + 0x676f02d9, 14);
199: MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
200:
201: MD5STEP(F3, a, b, c, d, in[ 5] + 0xfffa3942, 4);
202: MD5STEP(F3, d, a, b, c, in[ 8] + 0x8771f681, 11);
203: MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
204: MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
205: MD5STEP(F3, a, b, c, d, in[ 1] + 0xa4beea44, 4);
206: MD5STEP(F3, d, a, b, c, in[ 4] + 0x4bdecfa9, 11);
207: MD5STEP(F3, c, d, a, b, in[ 7] + 0xf6bb4b60, 16);
208: MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
209: MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
210: MD5STEP(F3, d, a, b, c, in[ 0] + 0xeaa127fa, 11);
211: MD5STEP(F3, c, d, a, b, in[ 3] + 0xd4ef3085, 16);
212: MD5STEP(F3, b, c, d, a, in[ 6] + 0x04881d05, 23);
213: MD5STEP(F3, a, b, c, d, in[ 9] + 0xd9d4d039, 4);
214: MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
215: MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
216: MD5STEP(F3, b, c, d, a, in[2 ] + 0xc4ac5665, 23);
217:
218: MD5STEP(F4, a, b, c, d, in[ 0] + 0xf4292244, 6);
219: MD5STEP(F4, d, a, b, c, in[7 ] + 0x432aff97, 10);
220: MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
221: MD5STEP(F4, b, c, d, a, in[5 ] + 0xfc93a039, 21);
222: MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
223: MD5STEP(F4, d, a, b, c, in[3 ] + 0x8f0ccc92, 10);
224: MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
225: MD5STEP(F4, b, c, d, a, in[1 ] + 0x85845dd1, 21);
226: MD5STEP(F4, a, b, c, d, in[8 ] + 0x6fa87e4f, 6);
227: MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
228: MD5STEP(F4, c, d, a, b, in[6 ] + 0xa3014314, 15);
229: MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
230: MD5STEP(F4, a, b, c, d, in[4 ] + 0xf7537e82, 6);
231: MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
232: MD5STEP(F4, c, d, a, b, in[2 ] + 0x2ad7d2bb, 15);
233: MD5STEP(F4, b, c, d, a, in[9 ] + 0xeb86d391, 21);
234:
235: state[0] += a;
236: state[1] += b;
237: state[2] += c;
238: state[3] += d;
239: }
CVSweb
![[BACK]](/icons/back.gif){kind=icon}
Return to md5.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / sys / crypto