GNU libmicrohttpd  0.9.72
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 
36 void
37 MHD_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 
50 static void
51 MD5Transform (uint32_t state[4],
52  const uint8_t block[MD5_BLOCK_SIZE]);
53 
54 
60 void
61 MHD_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 
127 static void
128 MD5Transform (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 
229 void
230 MHD_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