2 * $Id: md5.c,v 1.1.1.1 2000/06/20 22:12:03 agmorgan Exp $
3 * $FreeBSD: src/contrib/libpam/modules/pam_unix/md5.c,v 1.1.1.1.2.2 2001/06/11 15:28:30 markm Exp $
5 * This code implements the MD5 message-digest algorithm.
6 * The algorithm is due to Ron Rivest. This code was
7 * written by Colin Plumb in 1993, no copyright is claimed.
8 * This code is in the public domain; do with it what you wish.
10 * Equivalent code is available from RSA Data Security, Inc.
11 * This code has been tested against that, and is equivalent,
12 * except that you don't need to include two pages of legalese
15 * To compute the message digest of a chunk of bytes, declare an
16 * MD5Context structure, pass it to MD5Init, call MD5Update as
17 * needed on buffers full of bytes, and then call MD5Final, which
18 * will fill a supplied 16-byte array with the digest.
26 #define byteReverse(buf, len) /* Nothing */
28 static void byteReverse(unsigned char *buf, unsigned longs);
32 * Note: this code is harmless on little-endian machines.
34 static void byteReverse(unsigned char *buf, unsigned longs)
38 t = (uint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
39 ((unsigned) buf[1] << 8 | buf[0]);
48 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
49 * initialization constants.
51 void MD5Name(MD5Init)(struct MD5Context *ctx)
53 ctx->buf[0] = 0x67452301U;
54 ctx->buf[1] = 0xefcdab89U;
55 ctx->buf[2] = 0x98badcfeU;
56 ctx->buf[3] = 0x10325476U;
63 * Update context to reflect the concatenation of another buffer full
66 void MD5Name(MD5Update)(struct MD5Context *ctx, unsigned const char *buf, unsigned len)
73 if ((ctx->bits[0] = t + ((uint32) len << 3)) < t)
74 ctx->bits[1]++; /* Carry from low to high */
75 ctx->bits[1] += len >> 29;
77 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
79 /* Handle any leading odd-sized chunks */
82 unsigned char *p = (unsigned char *) ctx->in + t;
90 byteReverse(ctx->in, 16);
91 MD5Name(MD5Transform)(ctx->buf, (uint32 *) ctx->in);
95 /* Process data in 64-byte chunks */
98 memcpy(ctx->in, buf, 64);
99 byteReverse(ctx->in, 16);
100 MD5Name(MD5Transform)(ctx->buf, (uint32 *) ctx->in);
105 /* Handle any remaining bytes of data. */
107 memcpy(ctx->in, buf, len);
111 * Final wrapup - pad to 64-byte boundary with the bit pattern
112 * 1 0* (64-bit count of bits processed, MSB-first)
114 void MD5Name(MD5Final)(unsigned char digest[16], struct MD5Context *ctx)
119 /* Compute number of bytes mod 64 */
120 count = (ctx->bits[0] >> 3) & 0x3F;
122 /* Set the first char of padding to 0x80. This is safe since there is
123 always at least one byte free */
127 /* Bytes of padding needed to make 64 bytes */
128 count = 64 - 1 - count;
130 /* Pad out to 56 mod 64 */
132 /* Two lots of padding: Pad the first block to 64 bytes */
134 byteReverse(ctx->in, 16);
135 MD5Name(MD5Transform)(ctx->buf, (uint32 *) ctx->in);
137 /* Now fill the next block with 56 bytes */
138 memset(ctx->in, 0, 56);
140 /* Pad block to 56 bytes */
141 memset(p, 0, count - 8);
143 byteReverse(ctx->in, 14);
145 /* Append length in bits and transform */
146 ((uint32 *) ctx->in)[14] = ctx->bits[0];
147 ((uint32 *) ctx->in)[15] = ctx->bits[1];
149 MD5Name(MD5Transform)(ctx->buf, (uint32 *) ctx->in);
150 byteReverse((unsigned char *) ctx->buf, 4);
151 memcpy(digest, ctx->buf, 16);
152 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
157 /* The four core functions - F1 is optimized somewhat */
159 /* #define F1(x, y, z) (x & y | ~x & z) */
160 #define F1(x, y, z) (z ^ (x & (y ^ z)))
161 #define F2(x, y, z) F1(z, x, y)
162 #define F3(x, y, z) (x ^ y ^ z)
163 #define F4(x, y, z) (y ^ (x | ~z))
165 /* This is the central step in the MD5 algorithm. */
166 #define MD5STEP(f, w, x, y, z, data, s) \
167 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
170 * The core of the MD5 algorithm, this alters an existing MD5 hash to
171 * reflect the addition of 16 longwords of new data. MD5Update blocks
172 * the data and converts bytes into longwords for this routine.
174 void MD5Name(MD5Transform)(uint32 buf[4], uint32 const in[16])
176 register uint32 a, b, c, d;
183 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478U, 7);
184 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756U, 12);
185 MD5STEP(F1, c, d, a, b, in[2] + 0x242070dbU, 17);
186 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceeeU, 22);
187 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0fafU, 7);
188 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62aU, 12);
189 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613U, 17);
190 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501U, 22);
191 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8U, 7);
192 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7afU, 12);
193 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1U, 17);
194 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7beU, 22);
195 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122U, 7);
196 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193U, 12);
197 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438eU, 17);
198 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821U, 22);
200 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562U, 5);
201 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340U, 9);
202 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51U, 14);
203 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aaU, 20);
204 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105dU, 5);
205 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453U, 9);
206 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681U, 14);
207 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8U, 20);
208 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6U, 5);
209 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6U, 9);
210 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87U, 14);
211 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14edU, 20);
212 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905U, 5);
213 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8U, 9);
214 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9U, 14);
215 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8aU, 20);
217 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942U, 4);
218 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681U, 11);
219 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122U, 16);
220 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380cU, 23);
221 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44U, 4);
222 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9U, 11);
223 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60U, 16);
224 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70U, 23);
225 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6U, 4);
226 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127faU, 11);
227 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085U, 16);
228 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05U, 23);
229 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039U, 4);
230 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5U, 11);
231 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8U, 16);
232 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665U, 23);
234 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244U, 6);
235 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97U, 10);
236 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7U, 15);
237 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039U, 21);
238 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3U, 6);
239 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92U, 10);
240 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47dU, 15);
241 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1U, 21);
242 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4fU, 6);
243 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0U, 10);
244 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314U, 15);
245 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1U, 21);
246 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82U, 6);
247 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235U, 10);
248 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bbU, 15);
249 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391U, 21);