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.
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
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.
18 typedef unsigned long word32;
19 typedef unsigned char byte;
27 void MD5Init(struct MD5Context *context);
28 void MD5Update(struct MD5Context *context, byte const *buf, int len);
29 void MD5Final(byte digest[16], struct MD5Context *context);
30 void MD5Transform(word32 buf[4], word32 const in[16]);
34 * Shuffle the bytes into little-endian order within words, as per the
35 * MD5 spec. Note: this code works regardless of the byte order.
38 byteSwap(word32 *buf, unsigned words)
40 byte *p = (byte *)buf;
43 *buf++ = (word32)((unsigned)p[3] << 8 | p[2]) << 16 |
44 ((unsigned)p[1] << 8 | p[0]);
50 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
51 * initialization constants.
54 MD5Init(struct MD5Context *ctx)
56 ctx->buf[0] = 0x67452301;
57 ctx->buf[1] = 0xefcdab89;
58 ctx->buf[2] = 0x98badcfe;
59 ctx->buf[3] = 0x10325476;
66 * Update context to reflect the concatenation of another buffer full
70 MD5Update(struct MD5Context *ctx, byte const *buf, int len)
74 /* Update byte count */
77 if ((ctx->bytes[0] = t + len) < t)
78 ctx->bytes[1]++; /* Carry from low to high */
80 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
81 if ((unsigned)t > len) {
82 bcopy(buf, (byte *)ctx->in + 64 - (unsigned)t, len);
85 /* First chunk is an odd size */
86 bcopy(buf,(byte *)ctx->in + 64 - (unsigned)t, (unsigned)t);
87 byteSwap(ctx->in, 16);
88 MD5Transform(ctx->buf, ctx->in);
92 /* Process data in 64-byte chunks */
94 bcopy(buf, ctx->in, 64);
95 byteSwap(ctx->in, 16);
96 MD5Transform(ctx->buf, ctx->in);
101 /* Handle any remaining bytes of data. */
102 bcopy(buf, ctx->in, len);
106 * Final wrapup - pad to 64-byte boundary with the bit pattern
107 * 1 0* (64-bit count of bits processed, MSB-first)
110 MD5Final(byte digest[16], struct MD5Context *ctx)
112 int count = (int)(ctx->bytes[0] & 0x3f); /* Bytes in ctx->in */
113 byte *p = (byte *)ctx->in + count; /* First unused byte */
115 /* Set the first char of padding to 0x80. There is always room. */
118 /* Bytes of padding needed to make 56 bytes (-8..55) */
119 count = 56 - 1 - count;
121 if (count < 0) { /* Padding forces an extra block */
123 byteSwap(ctx->in, 16);
124 MD5Transform(ctx->buf, ctx->in);
129 byteSwap(ctx->in, 14);
131 /* Append length in bits and transform */
132 ctx->in[14] = ctx->bytes[0] << 3;
133 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
134 MD5Transform(ctx->buf, ctx->in);
136 byteSwap(ctx->buf, 4);
137 bcopy(ctx->buf, digest, 16);
138 bzero(ctx,sizeof(ctx));
142 /* The four core functions - F1 is optimized somewhat */
144 /* #define F1(x, y, z) (x & y | ~x & z) */
145 #define F1(x, y, z) (z ^ (x & (y ^ z)))
146 #define F2(x, y, z) F1(z, x, y)
147 #define F3(x, y, z) (x ^ y ^ z)
148 #define F4(x, y, z) (y ^ (x | ~z))
150 /* This is the central step in the MD5 algorithm. */
151 #define MD5STEP(f,w,x,y,z,in,s) \
152 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
155 * The core of the MD5 algorithm, this alters an existing MD5 hash to
156 * reflect the addition of 16 longwords of new data. MD5Update blocks
157 * the data and converts bytes into longwords for this routine.
161 MD5Transform(word32 buf[4], word32 const in[16])
163 register word32 a, b, c, d;
170 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
171 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
172 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
173 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
174 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
175 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
176 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
177 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
178 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
179 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
180 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
181 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
182 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
183 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
184 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
185 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
187 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
188 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
189 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
190 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
191 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
192 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
193 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
194 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
195 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
196 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
197 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
198 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
199 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
200 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
201 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
202 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
204 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
205 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
206 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
207 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
208 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
209 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
210 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
211 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
212 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
213 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
214 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
215 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
216 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
217 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
218 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
219 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
221 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
222 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
223 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
224 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
225 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
226 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
227 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
228 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
229 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
230 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
231 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
232 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
233 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
234 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
235 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
236 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);