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) 1996-2019, 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 */
38static uint8 *
39createPaddedCopyWithLength(const uint8 *b, uint32 *l)
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
96static void
97doTheRounds(uint32 X[16], uint32 state[4])
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
187static int
188calculateDigestFromBuffer(const uint8 *b, uint32 len, uint8 sum[16])
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
247static void
248bytesToHex(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 */
292bool
293pg_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
304bool
305pg_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 */
322bool
323pg_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}
349