GNU libmicrohttpd  0.9.59
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 /*
46  * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
47  * initialization constants.
48  */
49 void
50 MD5Init(struct MD5Context *ctx)
51 {
52  if (!ctx)
53  return;
54 
55  ctx->count = 0;
56  ctx->state[0] = 0x67452301;
57  ctx->state[1] = 0xefcdab89;
58  ctx->state[2] = 0x98badcfe;
59  ctx->state[3] = 0x10325476;
60 }
61 
62 /*
63  * Update context to reflect the concatenation of another buffer full
64  * of bytes.
65  */
66 void
67 MD5Update(struct MD5Context *ctx, const unsigned char *input, size_t len)
68 {
69  size_t have, need;
70 
71  if (!ctx || !input)
72  return;
73 
74  /* Check how many bytes we already have and how many more we need. */
75  have = (size_t)((ctx->count >> 3) & (MD5_BLOCK_SIZE - 1));
76  need = MD5_BLOCK_SIZE - have;
77 
78  /* Update bitcount */
79  ctx->count += (uint64_t)len << 3;
80 
81  if (len >= need)
82  {
83  if (have != 0)
84  {
85  memcpy(ctx->buffer + have, input, need);
86  MD5Transform(ctx->state, ctx->buffer);
87  input += need;
88  len -= need;
89  have = 0;
90  }
91 
92  /* Process data in MD5_BLOCK_SIZE-byte chunks. */
93  while (len >= MD5_BLOCK_SIZE)
94  {
95  MD5Transform(ctx->state, input);
96  input += MD5_BLOCK_SIZE;
97  len -= MD5_BLOCK_SIZE;
98  }
99  }
100 
101  /* Handle any remaining bytes of data. */
102  if (len != 0)
103  memcpy(ctx->buffer + have, input, len);
104 }
105 
106 /*
107  * Pad pad to 64-byte boundary with the bit pattern
108  * 1 0* (64-bit count of bits processed, MSB-first)
109  */
110 void
111 MD5Pad(struct MD5Context *ctx)
112 {
113  uint8_t count[8];
114  size_t padlen;
115 
116  if (!ctx)
117  return;
118 
119  /* Convert count to 8 bytes in little endian order. */
120  PUT_64BIT_LE(count, ctx->count);
121 
122  /* Pad out to 56 mod 64. */
123  padlen = MD5_BLOCK_SIZE -
124  ((ctx->count >> 3) & (MD5_BLOCK_SIZE - 1));
125  if (padlen < 1 + 8)
126  padlen += MD5_BLOCK_SIZE;
127  MD5Update(ctx, PADDING, padlen - 8); /* padlen - 8 <= 64 */
128  MD5Update(ctx, count, 8);
129 }
130 
131 /*
132  * Final wrapup--call MD5Pad, fill in digest and zero out ctx.
133  */
134 void
135 MD5Final(unsigned char digest[MD5_DIGEST_SIZE], struct MD5Context *ctx)
136 {
137  int i;
138 
139  if (!ctx || !digest)
140  return;
141 
142  MD5Pad(ctx);
143  for (i = 0; i < 4; i++)
144  PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
145 
146  memset(ctx, 0, sizeof(*ctx));
147 }
148 
149 
150 /* The four core functions - F1 is optimized somewhat */
151 
152 /* #define F1(x, y, z) (x & y | ~x & z) */
153 #define F1(x, y, z) (z ^ (x & (y ^ z)))
154 #define F2(x, y, z) F1(z, x, y)
155 #define F3(x, y, z) (x ^ y ^ z)
156 #define F4(x, y, z) (y ^ (x | ~z))
157 
158 /* This is the central step in the MD5 algorithm. */
159 #define MD5STEP(f, w, x, y, z, data, s) \
160  ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
161 
162 /*
163  * The core of the MD5 algorithm, this alters an existing MD5 hash to
164  * reflect the addition of 16 longwords of new data. MD5Update blocks
165  * the data and converts bytes into longwords for this routine.
166  */
167 void
168 MD5Transform(uint32_t state[4], const uint8_t block[MD5_BLOCK_SIZE])
169 {
170  uint32_t a, b, c, d, in[MD5_BLOCK_SIZE / 4];
171 
172 #if _MHD_BYTE_ORDER == _MHD_LITTLE_ENDIAN
173  memcpy(in, block, sizeof(in));
174 #else
175  for (a = 0; a < MD5_BLOCK_SIZE / 4; a++)
176  {
177  in[a] = (uint32_t)(
178  (uint32_t)(block[a * 4 + 0]) |
179  (uint32_t)(block[a * 4 + 1]) << 8 |
180  (uint32_t)(block[a * 4 + 2]) << 16 |
181  (uint32_t)(block[a * 4 + 3]) << 24);
182  }
183 #endif
184 
185  a = state[0];
186  b = state[1];
187  c = state[2];
188  d = state[3];
189 
190  MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
191  MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
192  MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
193  MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
194  MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
195  MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
196  MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
197  MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
198  MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
199  MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
200  MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
201  MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
202  MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
203  MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
204  MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
205  MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
206 
207  MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
208  MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
209  MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
210  MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
211  MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
212  MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
213  MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
214  MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
215  MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
216  MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
217  MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
218  MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
219  MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
220  MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
221  MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
222  MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
223 
224  MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
225  MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
226  MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
227  MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
228  MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
229  MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
230  MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
231  MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
232  MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
233  MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
234  MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
235  MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
236  MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
237  MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
238  MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
239  MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
240 
241  MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
242  MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
243  MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
244  MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
245  MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
246  MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
247  MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
248  MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
249  MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
250  MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
251  MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
252  MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
253  MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
254  MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
255  MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
256  MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
257 
258  state[0] += a;
259  state[1] += b;
260  state[2] += c;
261  state[3] += d;
262 }
263 
264 /* end of md5.c */
#define F2(x, y, z)
Definition: md5.c:154
enum MHD_CONNECTION_STATE state
Definition: internal.h:899
static uint8_t PADDING[MD5_BLOCK_SIZE]
Definition: md5.c:39
#define F1(x, y, z)
Definition: md5.c:153
uint8_t buffer[MD5_BLOCK_SIZE]
Definition: md5.h:31
uint64_t count
Definition: md5.h:30
macro definitions for host byte order
void MD5Update(struct MD5Context *ctx, const unsigned char *input, size_t len)
Definition: md5.c:67
#define MD5STEP(f, w, x, y, z, data, s)
Definition: md5.c:159
#define F3(x, y, z)
Definition: md5.c:155
void MD5Transform(uint32_t state[4], const uint8_t block[MD5_BLOCK_SIZE])
Definition: md5.c:168
#define F4(x, y, z)
Definition: md5.c:156
#define MD5_BLOCK_SIZE
Definition: md5.h:23
void MD5Final(unsigned char digest[MD5_DIGEST_SIZE], struct MD5Context *ctx)
Definition: md5.c:135
#define PUT_64BIT_LE(cp, value)
Definition: md5.c:23
void MD5Init(struct MD5Context *ctx)
Definition: md5.c:50
Definition: md5.h:27
#define PUT_32BIT_LE(cp, value)
Definition: md5.c:33
void MD5Pad(struct MD5Context *ctx)
Definition: md5.c:111
#define MD5_DIGEST_SIZE
Definition: md5.h:24
uint32_t state[4]
Definition: md5.h:29