GNU libmicrohttpd  0.9.63
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 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.
16  */
17 
18 /* Based on OpenBSD modifications */
19 
20 #include "md5.h"
21 #include "mhd_byteorder.h"
22 
23 #define PUT_64BIT_LE(cp, value) do { \
24  (cp)[7] = (uint8_t)((value) >> 56); \
25  (cp)[6] = (uint8_t)((value) >> 48); \
26  (cp)[5] = (uint8_t)((value) >> 40); \
27  (cp)[4] = (uint8_t)((value) >> 32); \
28  (cp)[3] = (uint8_t)((value) >> 24); \
29  (cp)[2] = (uint8_t)((value) >> 16); \
30  (cp)[1] = (uint8_t)((value) >> 8); \
31  (cp)[0] = (uint8_t)((value)); } while (0)
32 
33 #define PUT_32BIT_LE(cp, value) do { \
34  (cp)[3] = (uint8_t)((value) >> 24); \
35  (cp)[2] = (uint8_t)((value) >> 16); \
36  (cp)[1] = (uint8_t)((value) >> 8); \
37  (cp)[0] = (uint8_t)((value)); } while (0)
38 
39 static uint8_t PADDING[MD5_BLOCK_SIZE] = {
40  0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
41  0, 0, 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
43 };
44 
45 
52 void
53 MD5Init (void *ctx_)
54 {
55  struct MD5Context *ctx = ctx_;
56 
57  if (!ctx)
58  return;
59  ctx->count = 0;
60  ctx->state[0] = 0x67452301;
61  ctx->state[1] = 0xefcdab89;
62  ctx->state[2] = 0x98badcfe;
63  ctx->state[3] = 0x10325476;
64 }
65 
66 
71 static void
72 MD5Pad (struct MD5Context *ctx)
73 {
74  uint8_t count[8];
75  size_t padlen;
76 
77  if (!ctx)
78  return;
79 
80  /* Convert count to 8 bytes in little endian order. */
81  PUT_64BIT_LE(count, ctx->count);
82 
83  /* Pad out to 56 mod 64. */
84  padlen = MD5_BLOCK_SIZE -
85  ((ctx->count >> 3) & (MD5_BLOCK_SIZE - 1));
86  if (padlen < 1 + 8)
87  padlen += MD5_BLOCK_SIZE;
88  MD5Update(ctx, PADDING, padlen - 8); /* padlen - 8 <= 64 */
89  MD5Update(ctx, count, 8);
90 }
91 
92 
98 void
99 MD5Final (void *ctx_,
100  unsigned char digest[MD5_DIGEST_SIZE])
101 {
102  struct MD5Context *ctx = ctx_;
103  int i;
104 
105  if (!ctx || !digest)
106  return;
107 
108  MD5Pad(ctx);
109  for (i = 0; i < 4; i++)
110  PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
111 
112  memset(ctx, 0, sizeof(*ctx));
113 }
114 
115 
116 /* The four core functions - F1 is optimized somewhat */
117 
118 /* #define F1(x, y, z) (x & y | ~x & z) */
119 #define F1(x, y, z) (z ^ (x & (y ^ z)))
120 #define F2(x, y, z) F1(z, x, y)
121 #define F3(x, y, z) (x ^ y ^ z)
122 #define F4(x, y, z) (y ^ (x | ~z))
123 
124 /* This is the central step in the MD5 algorithm. */
125 #define MD5STEP(f, w, x, y, z, data, s) \
126  ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
127 
133 static void
134 MD5Transform (uint32_t state[4],
135  const uint8_t block[MD5_BLOCK_SIZE])
136 {
137  uint32_t a, b, c, d, in[MD5_BLOCK_SIZE / 4];
138 
139 #if _MHD_BYTE_ORDER == _MHD_LITTLE_ENDIAN
140  memcpy(in, block, sizeof(in));
141 #else
142  for (a = 0; a < MD5_BLOCK_SIZE / 4; a++)
143  {
144  in[a] = (uint32_t)(
145  (uint32_t)(block[a * 4 + 0]) |
146  (uint32_t)(block[a * 4 + 1]) << 8 |
147  (uint32_t)(block[a * 4 + 2]) << 16 |
148  (uint32_t)(block[a * 4 + 3]) << 24);
149  }
150 #endif
151 
152  a = state[0];
153  b = state[1];
154  c = state[2];
155  d = state[3];
156 
157  MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
158  MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
159  MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
160  MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
161  MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
162  MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
163  MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
164  MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
165  MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
166  MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
167  MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
168  MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
169  MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
170  MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
171  MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
172  MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
173 
174  MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
175  MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
176  MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
177  MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
178  MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
179  MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
180  MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
181  MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
182  MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
183  MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
184  MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
185  MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
186  MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
187  MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
188  MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
189  MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
190 
191  MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
192  MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
193  MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
194  MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
195  MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
196  MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
197  MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
198  MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
199  MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
200  MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
201  MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
202  MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
203  MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
204  MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
205  MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
206  MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
207 
208  MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
209  MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
210  MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
211  MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
212  MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
213  MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
214  MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
215  MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
216  MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
217  MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
218  MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
219  MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
220  MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
221  MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
222  MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
223  MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
224 
225  state[0] += a;
226  state[1] += b;
227  state[2] += c;
228  state[3] += d;
229 }
230 
231 
236 void
237 MD5Update (void *ctx_,
238  const uint8_t *input,
239  size_t len)
240 {
241  struct MD5Context *ctx = ctx_;
242  size_t have, need;
243 
244  if (!ctx || !input)
245  return;
246 
247  /* Check how many bytes we already have and how many more we need. */
248  have = (size_t)((ctx->count >> 3) & (MD5_BLOCK_SIZE - 1));
249  need = MD5_BLOCK_SIZE - have;
250 
251  /* Update bitcount */
252  ctx->count += (uint64_t)len << 3;
253 
254  if (len >= need)
255  {
256  if (have != 0)
257  {
258  memcpy (ctx->buffer + have,
259  input,
260  need);
261  MD5Transform(ctx->state, ctx->buffer);
262  input += need;
263  len -= need;
264  have = 0;
265  }
266 
267  /* Process data in MD5_BLOCK_SIZE-byte chunks. */
268  while (len >= MD5_BLOCK_SIZE)
269  {
270  MD5Transform (ctx->state,
271  (const unsigned char *) input);
272  input += MD5_BLOCK_SIZE;
273  len -= MD5_BLOCK_SIZE;
274  }
275  }
276 
277  /* Handle any remaining bytes of data. */
278  if (0 != len)
279  memcpy (ctx->buffer + have,
280  input,
281  len);
282 }
283 
284 
285 
286 /* end of md5.c */
void MD5Final(void *ctx_, unsigned char digest[MD5_DIGEST_SIZE])
Definition: md5.c:99
#define F2(x, y, z)
Definition: md5.c:120
static uint8_t PADDING[MD5_BLOCK_SIZE]
Definition: md5.c:39
static void MD5Pad(struct MD5Context *ctx)
Definition: md5.c:72
#define F1(x, y, z)
Definition: md5.c:119
uint8_t buffer[MD5_BLOCK_SIZE]
Definition: md5.h:31
uint64_t count
Definition: md5.h:30
void MD5Init(void *ctx_)
Definition: md5.c:53
#define MD5STEP(f, w, x, y, z, data, s)
Definition: md5.c:125
#define F3(x, y, z)
Definition: md5.c:121
macro definitions for host byte order
#define F4(x, y, z)
Definition: md5.c:122
#define MD5_BLOCK_SIZE
Definition: md5.h:23
#define PUT_64BIT_LE(cp, value)
Definition: md5.c:23
Definition: md5.h:27
#define PUT_32BIT_LE(cp, value)
Definition: md5.c:33
#define MD5_DIGEST_SIZE
Definition: md5.h:24
void MD5Update(void *ctx_, const uint8_t *input, size_t len)
Definition: md5.c:237
static void MD5Transform(uint32_t state[4], const uint8_t block[MD5_BLOCK_SIZE])
Definition: md5.c:134
uint32_t state[4]
Definition: md5.h:29