GNU libmicrohttpd 0.9.71
md5.c
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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 MHD_MD5Init, call MHD_MD5Update as
14 * needed on buffers full of bytes, and then call MHD_MD5Final, which
15 * will fill a supplied 16-byte array with the digest.
16 */
17
18/* Based on OpenBSD modifications.
19 * Optimized by Karlson2k (Evgeny Grin). */
20
21#include "md5.h"
22#include <string.h>
23#ifdef HAVE_MEMORY_H
24#include <memory.h>
25#endif /* HAVE_MEMORY_H */
26#include "mhd_bithelpers.h"
27#include "mhd_assert.h"
28
29
36void
37MHD_MD5Init (void *ctx_)
38{
39 struct MD5Context *ctx = ctx_;
40
41 mhd_assert (ctx != NULL);
42 ctx->count = 0;
43 ctx->state[0] = 0x67452301;
44 ctx->state[1] = 0xefcdab89;
45 ctx->state[2] = 0x98badcfe;
46 ctx->state[3] = 0x10325476;
47}
48
49
50static void
51MD5Transform (uint32_t state[4],
52 const uint8_t block[MD5_BLOCK_SIZE]);
53
54
60void
61MHD_MD5Final (void *ctx_,
62 uint8_t digest[MD5_DIGEST_SIZE])
63{
64 struct MD5Context *ctx = ctx_;
65 uint64_t count_bits;
66 size_t have_bytes;
67
68 mhd_assert (ctx != NULL);
69 mhd_assert (digest != NULL);
70
71 /* Convert count to 8 bytes in little endian order. */
72 have_bytes = (ctx->count) & (MD5_BLOCK_SIZE - 1);
73
74 /* Pad data */
75 /* Buffer always have space for one byte or more. */
76 ctx->buffer[have_bytes++] = 0x80; /* First padding byte is 0x80 */
77
78 if (MD5_BLOCK_SIZE - have_bytes < 8)
79 { /* Not enough space to put number of bits */
80 while (have_bytes < MD5_BLOCK_SIZE)
81 ctx->buffer[have_bytes++] = 0;
82 MD5Transform (ctx->state, ctx->buffer);
83 have_bytes = 0; /* Additional block */
84 }
85 /* Pad out to 56 */
86 memset (ctx->buffer + have_bytes, 0, MD5_BLOCK_SIZE - have_bytes - 8);
87
88 /* Put number of bits */
89 count_bits = ctx->count << 3;
90 _MHD_PUT_64BIT_LE (ctx->buffer + 56, count_bits);
91 MD5Transform (ctx->state, ctx->buffer);
92
93 /* Put digest in LE mode */
94 _MHD_PUT_32BIT_LE (digest, ctx->state[0]);
95 _MHD_PUT_32BIT_LE (digest + 4, ctx->state[1]);
96 _MHD_PUT_32BIT_LE (digest + 8, ctx->state[2]);
97 _MHD_PUT_32BIT_LE (digest + 12, ctx->state[3]);
98
99 /* Erase buffer */
100 memset (ctx, 0, sizeof(*ctx));
101}
102
103
108#define MD5_BYTES_IN_WORD (32 / 8)
109
110/* The four core functions - F1 is optimized somewhat */
111
112/* #define F1(x, y, z) (x & y | ~x & z) */
113#define F1(x, y, z) (z ^ (x & (y ^ z)))
114#define F2(x, y, z) F1 (z, x, y)
115#define F3(x, y, z) (x ^ y ^ z)
116#define F4(x, y, z) (y ^ (x | ~z))
117
118/* This is the central step in the MD5 algorithm. */
119#define MD5STEP(f, w, x, y, z, data, s) \
120 (w += f (x, y, z) + data, w = w << s | w >> (32 - s), w += x)
121
127static void
128MD5Transform (uint32_t state[4],
129 const uint8_t block[MD5_BLOCK_SIZE])
130{
131 uint32_t a, b, c, d;
132
133#if _MHD_BYTE_ORDER == _MHD_LITTLE_ENDIAN
134 const uint32_t *in = (const uint32_t *) block;
135#else
136 uint32_t in[MD5_BLOCK_SIZE / MD5_BYTES_IN_WORD];
137 int i;
138
139 for (i = 0; i < MD5_BLOCK_SIZE / MD5_BYTES_IN_WORD; i++)
140 {
141 in[i] = _MHD_GET_32BIT_LE (block + i * MD5_BYTES_IN_WORD);
142 }
143#endif
144
145 a = state[0];
146 b = state[1];
147 c = state[2];
148 d = state[3];
149
150 MD5STEP (F1, a, b, c, d, in[0] + 0xd76aa478, 7);
151 MD5STEP (F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
152 MD5STEP (F1, c, d, a, b, in[2] + 0x242070db, 17);
153 MD5STEP (F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
154 MD5STEP (F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
155 MD5STEP (F1, d, a, b, c, in[5] + 0x4787c62a, 12);
156 MD5STEP (F1, c, d, a, b, in[6] + 0xa8304613, 17);
157 MD5STEP (F1, b, c, d, a, in[7] + 0xfd469501, 22);
158 MD5STEP (F1, a, b, c, d, in[8] + 0x698098d8, 7);
159 MD5STEP (F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
160 MD5STEP (F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
161 MD5STEP (F1, b, c, d, a, in[11] + 0x895cd7be, 22);
162 MD5STEP (F1, a, b, c, d, in[12] + 0x6b901122, 7);
163 MD5STEP (F1, d, a, b, c, in[13] + 0xfd987193, 12);
164 MD5STEP (F1, c, d, a, b, in[14] + 0xa679438e, 17);
165 MD5STEP (F1, b, c, d, a, in[15] + 0x49b40821, 22);
166
167 MD5STEP (F2, a, b, c, d, in[1] + 0xf61e2562, 5);
168 MD5STEP (F2, d, a, b, c, in[6] + 0xc040b340, 9);
169 MD5STEP (F2, c, d, a, b, in[11] + 0x265e5a51, 14);
170 MD5STEP (F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
171 MD5STEP (F2, a, b, c, d, in[5] + 0xd62f105d, 5);
172 MD5STEP (F2, d, a, b, c, in[10] + 0x02441453, 9);
173 MD5STEP (F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
174 MD5STEP (F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
175 MD5STEP (F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
176 MD5STEP (F2, d, a, b, c, in[14] + 0xc33707d6, 9);
177 MD5STEP (F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
178 MD5STEP (F2, b, c, d, a, in[8] + 0x455a14ed, 20);
179 MD5STEP (F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
180 MD5STEP (F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
181 MD5STEP (F2, c, d, a, b, in[7] + 0x676f02d9, 14);
182 MD5STEP (F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
183
184 MD5STEP (F3, a, b, c, d, in[5] + 0xfffa3942, 4);
185 MD5STEP (F3, d, a, b, c, in[8] + 0x8771f681, 11);
186 MD5STEP (F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
187 MD5STEP (F3, b, c, d, a, in[14] + 0xfde5380c, 23);
188 MD5STEP (F3, a, b, c, d, in[1] + 0xa4beea44, 4);
189 MD5STEP (F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
190 MD5STEP (F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
191 MD5STEP (F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
192 MD5STEP (F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
193 MD5STEP (F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
194 MD5STEP (F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
195 MD5STEP (F3, b, c, d, a, in[6] + 0x04881d05, 23);
196 MD5STEP (F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
197 MD5STEP (F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
198 MD5STEP (F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
199 MD5STEP (F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
200
201 MD5STEP (F4, a, b, c, d, in[0] + 0xf4292244, 6);
202 MD5STEP (F4, d, a, b, c, in[7] + 0x432aff97, 10);
203 MD5STEP (F4, c, d, a, b, in[14] + 0xab9423a7, 15);
204 MD5STEP (F4, b, c, d, a, in[5] + 0xfc93a039, 21);
205 MD5STEP (F4, a, b, c, d, in[12] + 0x655b59c3, 6);
206 MD5STEP (F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
207 MD5STEP (F4, c, d, a, b, in[10] + 0xffeff47d, 15);
208 MD5STEP (F4, b, c, d, a, in[1] + 0x85845dd1, 21);
209 MD5STEP (F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
210 MD5STEP (F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
211 MD5STEP (F4, c, d, a, b, in[6] + 0xa3014314, 15);
212 MD5STEP (F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
213 MD5STEP (F4, a, b, c, d, in[4] + 0xf7537e82, 6);
214 MD5STEP (F4, d, a, b, c, in[11] + 0xbd3af235, 10);
215 MD5STEP (F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
216 MD5STEP (F4, b, c, d, a, in[9] + 0xeb86d391, 21);
217
218 state[0] += a;
219 state[1] += b;
220 state[2] += c;
221 state[3] += d;
222}
223
224
229void
230MHD_MD5Update (void *ctx_,
231 const uint8_t *input,
232 size_t len)
233{
234 struct MD5Context *ctx = ctx_;
235 size_t have, need;
236
237 mhd_assert (ctx != NULL);
238 mhd_assert ((ctx != NULL) || (len == 0));
239
240 /* Check how many bytes we already have and how many more we need. */
241 have = (size_t) ((ctx->count) & (MD5_BLOCK_SIZE - 1));
242 need = MD5_BLOCK_SIZE - have;
243
244 /* Update bytecount */
245 ctx->count += (uint64_t) len;
246
247 if (len >= need)
248 {
249 if (have != 0)
250 {
251 memcpy (ctx->buffer + have,
252 input,
253 need);
254 MD5Transform (ctx->state, ctx->buffer);
255 input += need;
256 len -= need;
257 have = 0;
258 }
259
260 /* Process data in MD5_BLOCK_SIZE-byte chunks. */
261 while (len >= MD5_BLOCK_SIZE)
262 {
263 MD5Transform (ctx->state,
264 (const unsigned char *) input);
265 input += MD5_BLOCK_SIZE;
266 len -= MD5_BLOCK_SIZE;
267 }
268 }
269
270 /* Handle any remaining bytes of data. */
271 if (0 != len)
272 memcpy (ctx->buffer + have,
273 input,
274 len);
275}
276
277
278/* end of md5.c */
#define mhd_assert(CHK)
Definition: mhd_assert.h:39
#define NULL
Definition: reason_phrase.c:30
#define MD5STEP(f, w, x, y, z, data, s)
Definition: md5.c:119
void MHD_MD5Update(void *ctx_, const uint8_t *input, size_t len)
Definition: md5.c:230
void MHD_MD5Final(void *ctx_, uint8_t digest[MD5_DIGEST_SIZE])
Definition: md5.c:61
#define F1(x, y, z)
Definition: md5.c:113
#define F4(x, y, z)
Definition: md5.c:116
void MHD_MD5Init(void *ctx_)
Definition: md5.c:37
#define F3(x, y, z)
Definition: md5.c:115
static void MD5Transform(uint32_t state[4], const uint8_t block[MD5_BLOCK_SIZE])
Definition: md5.c:128
#define F2(x, y, z)
Definition: md5.c:114
#define MD5_BYTES_IN_WORD
Definition: md5.c:108
#define MD5_BLOCK_SIZE
Definition: md5.h:25
#define MD5_DIGEST_SIZE
Definition: md5.h:26
macros for bits manipulations
#define _MHD_PUT_64BIT_LE(addr, value64)
#define _MHD_GET_32BIT_LE(addr)
#define _MHD_PUT_32BIT_LE(addr, value32)
macros for mhd_assert()
Definition: md5.h:30
uint32_t state[4]
Definition: md5.h:31
uint64_t count
Definition: md5.h:32
uint8_t buffer[MD5_BLOCK_SIZE]
Definition: md5.h:33