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md5.c
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1 /*
2  * md5.c
3  *
4  * Implements the MD5 Message-Digest Algorithm as specified in
5  * RFC 1321. This implementation is a simple one, in that it
6  * needs every input byte to be buffered before doing any
7  * calculations. I do not expect this file to be used for
8  * general purpose MD5'ing of large amounts of data, only for
9  * generating hashed passwords from limited input.
10  *
11  * Sverre H. Huseby <sverrehu@online.no>
12  *
13  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
14  * Portions Copyright (c) 1994, Regents of the University of California
15  *
16  * IDENTIFICATION
17  * src/common/md5.c
18  */
19 
20 #ifndef FRONTEND
21 #include "postgres.h"
22 #else
23 #include "postgres_fe.h"
24 #endif
25 
26 #include "common/md5.h"
27 
28 
29 /*
30  * PRIVATE FUNCTIONS
31  */
32 
33 
34 /*
35  * The returned array is allocated using malloc. the caller should free it
36  * when it is no longer needed.
37  */
38 static uint8 *
40 {
41  uint8 *ret;
42  uint32 q;
43  uint32 len,
44  newLen448;
45  uint32 len_high,
46  len_low; /* 64-bit value split into 32-bit sections */
47 
48  len = ((b == NULL) ? 0 : *l);
49  newLen448 = len + 64 - (len % 64) - 8;
50  if (newLen448 <= len)
51  newLen448 += 64;
52 
53  *l = newLen448 + 8;
54  if ((ret = (uint8 *) malloc(sizeof(uint8) * *l)) == NULL)
55  return NULL;
56 
57  if (b != NULL)
58  memcpy(ret, b, sizeof(uint8) * len);
59 
60  /* pad */
61  ret[len] = 0x80;
62  for (q = len + 1; q < newLen448; q++)
63  ret[q] = 0x00;
64 
65  /* append length as a 64 bit bitcount */
66  len_low = len;
67  /* split into two 32-bit values */
68  /* we only look at the bottom 32-bits */
69  len_high = len >> 29;
70  len_low <<= 3;
71  q = newLen448;
72  ret[q++] = (len_low & 0xff);
73  len_low >>= 8;
74  ret[q++] = (len_low & 0xff);
75  len_low >>= 8;
76  ret[q++] = (len_low & 0xff);
77  len_low >>= 8;
78  ret[q++] = (len_low & 0xff);
79  ret[q++] = (len_high & 0xff);
80  len_high >>= 8;
81  ret[q++] = (len_high & 0xff);
82  len_high >>= 8;
83  ret[q++] = (len_high & 0xff);
84  len_high >>= 8;
85  ret[q] = (len_high & 0xff);
86 
87  return ret;
88 }
89 
90 #define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
91 #define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
92 #define H(x, y, z) ((x) ^ (y) ^ (z))
93 #define I(x, y, z) ((y) ^ ((x) | ~(z)))
94 #define ROT_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
95 
96 static void
98 {
99  uint32 a,
100  b,
101  c,
102  d;
103 
104  a = state[0];
105  b = state[1];
106  c = state[2];
107  d = state[3];
108 
109  /* round 1 */
110  a = b + ROT_LEFT((a + F(b, c, d) + X[0] + 0xd76aa478), 7); /* 1 */
111  d = a + ROT_LEFT((d + F(a, b, c) + X[1] + 0xe8c7b756), 12); /* 2 */
112  c = d + ROT_LEFT((c + F(d, a, b) + X[2] + 0x242070db), 17); /* 3 */
113  b = c + ROT_LEFT((b + F(c, d, a) + X[3] + 0xc1bdceee), 22); /* 4 */
114  a = b + ROT_LEFT((a + F(b, c, d) + X[4] + 0xf57c0faf), 7); /* 5 */
115  d = a + ROT_LEFT((d + F(a, b, c) + X[5] + 0x4787c62a), 12); /* 6 */
116  c = d + ROT_LEFT((c + F(d, a, b) + X[6] + 0xa8304613), 17); /* 7 */
117  b = c + ROT_LEFT((b + F(c, d, a) + X[7] + 0xfd469501), 22); /* 8 */
118  a = b + ROT_LEFT((a + F(b, c, d) + X[8] + 0x698098d8), 7); /* 9 */
119  d = a + ROT_LEFT((d + F(a, b, c) + X[9] + 0x8b44f7af), 12); /* 10 */
120  c = d + ROT_LEFT((c + F(d, a, b) + X[10] + 0xffff5bb1), 17); /* 11 */
121  b = c + ROT_LEFT((b + F(c, d, a) + X[11] + 0x895cd7be), 22); /* 12 */
122  a = b + ROT_LEFT((a + F(b, c, d) + X[12] + 0x6b901122), 7); /* 13 */
123  d = a + ROT_LEFT((d + F(a, b, c) + X[13] + 0xfd987193), 12); /* 14 */
124  c = d + ROT_LEFT((c + F(d, a, b) + X[14] + 0xa679438e), 17); /* 15 */
125  b = c + ROT_LEFT((b + F(c, d, a) + X[15] + 0x49b40821), 22); /* 16 */
126 
127  /* round 2 */
128  a = b + ROT_LEFT((a + G(b, c, d) + X[1] + 0xf61e2562), 5); /* 17 */
129  d = a + ROT_LEFT((d + G(a, b, c) + X[6] + 0xc040b340), 9); /* 18 */
130  c = d + ROT_LEFT((c + G(d, a, b) + X[11] + 0x265e5a51), 14); /* 19 */
131  b = c + ROT_LEFT((b + G(c, d, a) + X[0] + 0xe9b6c7aa), 20); /* 20 */
132  a = b + ROT_LEFT((a + G(b, c, d) + X[5] + 0xd62f105d), 5); /* 21 */
133  d = a + ROT_LEFT((d + G(a, b, c) + X[10] + 0x02441453), 9); /* 22 */
134  c = d + ROT_LEFT((c + G(d, a, b) + X[15] + 0xd8a1e681), 14); /* 23 */
135  b = c + ROT_LEFT((b + G(c, d, a) + X[4] + 0xe7d3fbc8), 20); /* 24 */
136  a = b + ROT_LEFT((a + G(b, c, d) + X[9] + 0x21e1cde6), 5); /* 25 */
137  d = a + ROT_LEFT((d + G(a, b, c) + X[14] + 0xc33707d6), 9); /* 26 */
138  c = d + ROT_LEFT((c + G(d, a, b) + X[3] + 0xf4d50d87), 14); /* 27 */
139  b = c + ROT_LEFT((b + G(c, d, a) + X[8] + 0x455a14ed), 20); /* 28 */
140  a = b + ROT_LEFT((a + G(b, c, d) + X[13] + 0xa9e3e905), 5); /* 29 */
141  d = a + ROT_LEFT((d + G(a, b, c) + X[2] + 0xfcefa3f8), 9); /* 30 */
142  c = d + ROT_LEFT((c + G(d, a, b) + X[7] + 0x676f02d9), 14); /* 31 */
143  b = c + ROT_LEFT((b + G(c, d, a) + X[12] + 0x8d2a4c8a), 20); /* 32 */
144 
145  /* round 3 */
146  a = b + ROT_LEFT((a + H(b, c, d) + X[5] + 0xfffa3942), 4); /* 33 */
147  d = a + ROT_LEFT((d + H(a, b, c) + X[8] + 0x8771f681), 11); /* 34 */
148  c = d + ROT_LEFT((c + H(d, a, b) + X[11] + 0x6d9d6122), 16); /* 35 */
149  b = c + ROT_LEFT((b + H(c, d, a) + X[14] + 0xfde5380c), 23); /* 36 */
150  a = b + ROT_LEFT((a + H(b, c, d) + X[1] + 0xa4beea44), 4); /* 37 */
151  d = a + ROT_LEFT((d + H(a, b, c) + X[4] + 0x4bdecfa9), 11); /* 38 */
152  c = d + ROT_LEFT((c + H(d, a, b) + X[7] + 0xf6bb4b60), 16); /* 39 */
153  b = c + ROT_LEFT((b + H(c, d, a) + X[10] + 0xbebfbc70), 23); /* 40 */
154  a = b + ROT_LEFT((a + H(b, c, d) + X[13] + 0x289b7ec6), 4); /* 41 */
155  d = a + ROT_LEFT((d + H(a, b, c) + X[0] + 0xeaa127fa), 11); /* 42 */
156  c = d + ROT_LEFT((c + H(d, a, b) + X[3] + 0xd4ef3085), 16); /* 43 */
157  b = c + ROT_LEFT((b + H(c, d, a) + X[6] + 0x04881d05), 23); /* 44 */
158  a = b + ROT_LEFT((a + H(b, c, d) + X[9] + 0xd9d4d039), 4); /* 45 */
159  d = a + ROT_LEFT((d + H(a, b, c) + X[12] + 0xe6db99e5), 11); /* 46 */
160  c = d + ROT_LEFT((c + H(d, a, b) + X[15] + 0x1fa27cf8), 16); /* 47 */
161  b = c + ROT_LEFT((b + H(c, d, a) + X[2] + 0xc4ac5665), 23); /* 48 */
162 
163  /* round 4 */
164  a = b + ROT_LEFT((a + I(b, c, d) + X[0] + 0xf4292244), 6); /* 49 */
165  d = a + ROT_LEFT((d + I(a, b, c) + X[7] + 0x432aff97), 10); /* 50 */
166  c = d + ROT_LEFT((c + I(d, a, b) + X[14] + 0xab9423a7), 15); /* 51 */
167  b = c + ROT_LEFT((b + I(c, d, a) + X[5] + 0xfc93a039), 21); /* 52 */
168  a = b + ROT_LEFT((a + I(b, c, d) + X[12] + 0x655b59c3), 6); /* 53 */
169  d = a + ROT_LEFT((d + I(a, b, c) + X[3] + 0x8f0ccc92), 10); /* 54 */
170  c = d + ROT_LEFT((c + I(d, a, b) + X[10] + 0xffeff47d), 15); /* 55 */
171  b = c + ROT_LEFT((b + I(c, d, a) + X[1] + 0x85845dd1), 21); /* 56 */
172  a = b + ROT_LEFT((a + I(b, c, d) + X[8] + 0x6fa87e4f), 6); /* 57 */
173  d = a + ROT_LEFT((d + I(a, b, c) + X[15] + 0xfe2ce6e0), 10); /* 58 */
174  c = d + ROT_LEFT((c + I(d, a, b) + X[6] + 0xa3014314), 15); /* 59 */
175  b = c + ROT_LEFT((b + I(c, d, a) + X[13] + 0x4e0811a1), 21); /* 60 */
176  a = b + ROT_LEFT((a + I(b, c, d) + X[4] + 0xf7537e82), 6); /* 61 */
177  d = a + ROT_LEFT((d + I(a, b, c) + X[11] + 0xbd3af235), 10); /* 62 */
178  c = d + ROT_LEFT((c + I(d, a, b) + X[2] + 0x2ad7d2bb), 15); /* 63 */
179  b = c + ROT_LEFT((b + I(c, d, a) + X[9] + 0xeb86d391), 21); /* 64 */
180 
181  state[0] += a;
182  state[1] += b;
183  state[2] += c;
184  state[3] += d;
185 }
186 
187 static int
189 {
190  register uint32 i,
191  j,
192  k,
193  newI;
194  uint32 l;
195  uint8 *input;
196  register uint32 *wbp;
197  uint32 workBuff[16],
198  state[4];
199 
200  l = len;
201 
202  state[0] = 0x67452301;
203  state[1] = 0xEFCDAB89;
204  state[2] = 0x98BADCFE;
205  state[3] = 0x10325476;
206 
207  if ((input = createPaddedCopyWithLength(b, &l)) == NULL)
208  return 0;
209 
210  for (i = 0;;)
211  {
212  if ((newI = i + 16 * 4) > l)
213  break;
214  k = i + 3;
215  for (j = 0; j < 16; j++)
216  {
217  wbp = (workBuff + j);
218  *wbp = input[k--];
219  *wbp <<= 8;
220  *wbp |= input[k--];
221  *wbp <<= 8;
222  *wbp |= input[k--];
223  *wbp <<= 8;
224  *wbp |= input[k];
225  k += 7;
226  }
227  doTheRounds(workBuff, state);
228  i = newI;
229  }
230  free(input);
231 
232  j = 0;
233  for (i = 0; i < 4; i++)
234  {
235  k = state[i];
236  sum[j++] = (k & 0xff);
237  k >>= 8;
238  sum[j++] = (k & 0xff);
239  k >>= 8;
240  sum[j++] = (k & 0xff);
241  k >>= 8;
242  sum[j++] = (k & 0xff);
243  }
244  return 1;
245 }
246 
247 static void
248 bytesToHex(uint8 b[16], char *s)
249 {
250  static const char *hex = "0123456789abcdef";
251  int q,
252  w;
253 
254  for (q = 0, w = 0; q < 16; q++)
255  {
256  s[w++] = hex[(b[q] >> 4) & 0x0F];
257  s[w++] = hex[b[q] & 0x0F];
258  }
259  s[w] = '\0';
260 }
261 
262 /*
263  * PUBLIC FUNCTIONS
264  */
265 
266 /*
267  * pg_md5_hash
268  *
269  * Calculates the MD5 sum of the bytes in a buffer.
270  *
271  * SYNOPSIS #include "md5.h"
272  * int pg_md5_hash(const void *buff, size_t len, char *hexsum)
273  *
274  * INPUT buff the buffer containing the bytes that you want
275  * the MD5 sum of.
276  * len number of bytes in the buffer.
277  *
278  * OUTPUT hexsum the MD5 sum as a '\0'-terminated string of
279  * hexadecimal digits. an MD5 sum is 16 bytes long.
280  * each byte is represented by two heaxadecimal
281  * characters. you thus need to provide an array
282  * of 33 characters, including the trailing '\0'.
283  *
284  * RETURNS false on failure (out of memory for internal buffers) or
285  * true on success.
286  *
287  * STANDARDS MD5 is described in RFC 1321.
288  *
289  * AUTHOR Sverre H. Huseby <sverrehu@online.no>
290  *
291  */
292 bool
293 pg_md5_hash(const void *buff, size_t len, char *hexsum)
294 {
295  uint8 sum[16];
296 
297  if (!calculateDigestFromBuffer(buff, len, sum))
298  return false;
299 
300  bytesToHex(sum, hexsum);
301  return true;
302 }
303 
304 bool
305 pg_md5_binary(const void *buff, size_t len, void *outbuf)
306 {
307  if (!calculateDigestFromBuffer(buff, len, outbuf))
308  return false;
309  return true;
310 }
311 
312 
313 /*
314  * Computes MD5 checksum of "passwd" (a null-terminated string) followed
315  * by "salt" (which need not be null-terminated).
316  *
317  * Output format is "md5" followed by a 32-hex-digit MD5 checksum.
318  * Hence, the output buffer "buf" must be at least 36 bytes long.
319  *
320  * Returns TRUE if okay, FALSE on error (out of memory).
321  */
322 bool
323 pg_md5_encrypt(const char *passwd, const char *salt, size_t salt_len,
324  char *buf)
325 {
326  size_t passwd_len = strlen(passwd);
327 
328  /* +1 here is just to avoid risk of unportable malloc(0) */
329  char *crypt_buf = malloc(passwd_len + salt_len + 1);
330  bool ret;
331 
332  if (!crypt_buf)
333  return false;
334 
335  /*
336  * Place salt at the end because it may be known by users trying to crack
337  * the MD5 output.
338  */
339  memcpy(crypt_buf, passwd, passwd_len);
340  memcpy(crypt_buf + passwd_len, salt, salt_len);
341 
342  strcpy(buf, "md5");
343  ret = pg_md5_hash(crypt_buf, passwd_len + salt_len, buf + 3);
344 
345  free(crypt_buf);
346 
347  return ret;
348 }
#define ROT_LEFT(x, n)
Definition: md5.c:94
unsigned char uint8
Definition: c.h:263
static void doTheRounds(uint32 X[16], uint32 state[4])
Definition: md5.c:97
static int calculateDigestFromBuffer(const uint8 *b, uint32 len, uint8 sum[16])
Definition: md5.c:188
#define G(x, y, z)
Definition: md5.c:91
#define malloc(a)
Definition: header.h:45
bool pg_md5_encrypt(const char *passwd, const char *salt, size_t salt_len, char *buf)
Definition: md5.c:323
#define F(x, y, z)
Definition: md5.c:90
char * c
static char * buf
Definition: pg_test_fsync.c:65
#define H(x, y, z)
Definition: md5.c:92
static void bytesToHex(uint8 b[16], char *s)
Definition: md5.c:248
unsigned int uint32
Definition: c.h:265
#define I(x, y, z)
Definition: md5.c:93
static uint8 * createPaddedCopyWithLength(const uint8 *b, uint32 *l)
Definition: md5.c:39
#define free(a)
Definition: header.h:60
#define NULL
Definition: c.h:226
bool pg_md5_hash(const void *buff, size_t len, char *hexsum)
Definition: md5.c:293
Definition: regguts.h:298
int i
bool pg_md5_binary(const void *buff, size_t len, void *outbuf)
Definition: md5.c:305