1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-md5.c md5 implementation (based on L Peter Deutsch implementation)
3 *
4 * Copyright (C) 2003 Red Hat Inc.
5 * Copyright (C) 1999, 2000 Aladdin Enterprises. All rights reserved.
6 *
7 * This software is provided 'as-is', without any express or implied
8 * warranty. In no event will the authors be held liable for any damages
9 * arising from the use of this software.
10 *
11 * Permission is granted to anyone to use this software for any purpose,
12 * including commercial applications, and to alter it and redistribute it
13 * freely, subject to the following restrictions:
14 *
15 * 1. The origin of this software must not be misrepresented; you must not
16 * claim that you wrote the original software. If you use this software
17 * in a product, an acknowledgment in the product documentation would be
18 * appreciated but is not required.
19 * 2. Altered source versions must be plainly marked as such, and must not be
20 * misrepresented as being the original software.
21 * 3. This notice may not be removed or altered from any source distribution.
22 *
23 * L. Peter Deutsch
24 * ghost@aladdin.com
25 */
26 /*
27 * Independent implementation of MD5 (RFC 1321).
28 *
29 * This code implements the MD5 Algorithm defined in RFC 1321.
30 * It is derived directly from the text of the RFC and not from the
31 * reference implementation.
32 *
33 * The original and principal author of md5.c is L. Peter Deutsch
34 * <ghost@aladdin.com>.
35 */
36
37 #include <config.h>
38 #include "dbus-internals.h"
39 #include "dbus-md5.h"
40 #include <string.h>
41
42 /**
43 * @defgroup DBusMD5 MD5 implementation
44 * @ingroup DBusInternals
45 * @brief MD5 hash
46 *
47 * Types and functions related to computing MD5 sums.
48 */
49
50 /**
51 * @defgroup DBusMD5Internals MD5 implementation details
52 * @ingroup DBusInternals
53 * @brief Internals of MD5 implementation.
54 *
55 * The implementation of MD5 (see http://www.ietf.org/rfc/rfc1321.txt).
56 * This MD5 implementation was written by L. Peter Deutsch and
57 * is not derived from the RSA reference implementation in the
58 * RFC. The version included in D-Bus comes from the Ghostscript
59 * 7.05 distribution.
60 *
61 * @{
62 */
63 #ifndef DOXYGEN_SHOULD_SKIP_THIS
64 /*
65 * For reference, here is the program that computed the T values.
66 */
67 #ifdef COMPUTE_T_VALUES
68 #include <math.h>
69 int
main(int argc,char ** argv)70 main(int argc, char **argv)
71 {
72 int i;
73 for (i = 1; i <= 64; ++i)
74 {
75 unsigned long v = (unsigned long)(4294967296.0 * fabs(sin((double)i)));
76
77 /*
78 * The following nonsense is only to avoid compiler warnings about
79 * "integer constant is unsigned in ANSI C, signed with -traditional".
80 */
81 if (v >> 31)
82 {
83 printf("#define T%d /* 0x%08lx */ (T_MASK ^ 0x%08lx)\n", i,
84 v, (unsigned long)(unsigned int)(~v));
85 } else {
86 printf("#define T%d 0x%08lx\n", i, v);
87 }
88 }
89 return 0;
90 }
91 #endif /* COMPUTE_T_VALUES */
92 /*
93 * End of T computation program.
94 */
95
96 #define T_MASK ((dbus_uint32_t)~0)
97 #define T1 /* 0xd76aa478 */ (T_MASK ^ 0x28955b87)
98 #define T2 /* 0xe8c7b756 */ (T_MASK ^ 0x173848a9)
99 #define T3 0x242070db
100 #define T4 /* 0xc1bdceee */ (T_MASK ^ 0x3e423111)
101 #define T5 /* 0xf57c0faf */ (T_MASK ^ 0x0a83f050)
102 #define T6 0x4787c62a
103 #define T7 /* 0xa8304613 */ (T_MASK ^ 0x57cfb9ec)
104 #define T8 /* 0xfd469501 */ (T_MASK ^ 0x02b96afe)
105 #define T9 0x698098d8
106 #define T10 /* 0x8b44f7af */ (T_MASK ^ 0x74bb0850)
107 #define T11 /* 0xffff5bb1 */ (T_MASK ^ 0x0000a44e)
108 #define T12 /* 0x895cd7be */ (T_MASK ^ 0x76a32841)
109 #define T13 0x6b901122
110 #define T14 /* 0xfd987193 */ (T_MASK ^ 0x02678e6c)
111 #define T15 /* 0xa679438e */ (T_MASK ^ 0x5986bc71)
112 #define T16 0x49b40821
113 #define T17 /* 0xf61e2562 */ (T_MASK ^ 0x09e1da9d)
114 #define T18 /* 0xc040b340 */ (T_MASK ^ 0x3fbf4cbf)
115 #define T19 0x265e5a51
116 #define T20 /* 0xe9b6c7aa */ (T_MASK ^ 0x16493855)
117 #define T21 /* 0xd62f105d */ (T_MASK ^ 0x29d0efa2)
118 #define T22 0x02441453
119 #define T23 /* 0xd8a1e681 */ (T_MASK ^ 0x275e197e)
120 #define T24 /* 0xe7d3fbc8 */ (T_MASK ^ 0x182c0437)
121 #define T25 0x21e1cde6
122 #define T26 /* 0xc33707d6 */ (T_MASK ^ 0x3cc8f829)
123 #define T27 /* 0xf4d50d87 */ (T_MASK ^ 0x0b2af278)
124 #define T28 0x455a14ed
125 #define T29 /* 0xa9e3e905 */ (T_MASK ^ 0x561c16fa)
126 #define T30 /* 0xfcefa3f8 */ (T_MASK ^ 0x03105c07)
127 #define T31 0x676f02d9
128 #define T32 /* 0x8d2a4c8a */ (T_MASK ^ 0x72d5b375)
129 #define T33 /* 0xfffa3942 */ (T_MASK ^ 0x0005c6bd)
130 #define T34 /* 0x8771f681 */ (T_MASK ^ 0x788e097e)
131 #define T35 0x6d9d6122
132 #define T36 /* 0xfde5380c */ (T_MASK ^ 0x021ac7f3)
133 #define T37 /* 0xa4beea44 */ (T_MASK ^ 0x5b4115bb)
134 #define T38 0x4bdecfa9
135 #define T39 /* 0xf6bb4b60 */ (T_MASK ^ 0x0944b49f)
136 #define T40 /* 0xbebfbc70 */ (T_MASK ^ 0x4140438f)
137 #define T41 0x289b7ec6
138 #define T42 /* 0xeaa127fa */ (T_MASK ^ 0x155ed805)
139 #define T43 /* 0xd4ef3085 */ (T_MASK ^ 0x2b10cf7a)
140 #define T44 0x04881d05
141 #define T45 /* 0xd9d4d039 */ (T_MASK ^ 0x262b2fc6)
142 #define T46 /* 0xe6db99e5 */ (T_MASK ^ 0x1924661a)
143 #define T47 0x1fa27cf8
144 #define T48 /* 0xc4ac5665 */ (T_MASK ^ 0x3b53a99a)
145 #define T49 /* 0xf4292244 */ (T_MASK ^ 0x0bd6ddbb)
146 #define T50 0x432aff97
147 #define T51 /* 0xab9423a7 */ (T_MASK ^ 0x546bdc58)
148 #define T52 /* 0xfc93a039 */ (T_MASK ^ 0x036c5fc6)
149 #define T53 0x655b59c3
150 #define T54 /* 0x8f0ccc92 */ (T_MASK ^ 0x70f3336d)
151 #define T55 /* 0xffeff47d */ (T_MASK ^ 0x00100b82)
152 #define T56 /* 0x85845dd1 */ (T_MASK ^ 0x7a7ba22e)
153 #define T57 0x6fa87e4f
154 #define T58 /* 0xfe2ce6e0 */ (T_MASK ^ 0x01d3191f)
155 #define T59 /* 0xa3014314 */ (T_MASK ^ 0x5cfebceb)
156 #define T60 0x4e0811a1
157 #define T61 /* 0xf7537e82 */ (T_MASK ^ 0x08ac817d)
158 #define T62 /* 0xbd3af235 */ (T_MASK ^ 0x42c50dca)
159 #define T63 0x2ad7d2bb
160 #define T64 /* 0xeb86d391 */ (T_MASK ^ 0x14792c6e)
161 #endif /* !DOXYGEN_SHOULD_SKIP_THIS */
162
163 static void
md5_process(DBusMD5Context * context,const unsigned char * data)164 md5_process(DBusMD5Context *context, const unsigned char *data /*[64]*/)
165 {
166 dbus_uint32_t
167 a = context->abcd[0], b = context->abcd[1],
168 c = context->abcd[2], d = context->abcd[3];
169 dbus_uint32_t t;
170
171 #ifdef WORDS_BIGENDIAN
172 /*
173 * On big-endian machines, we must arrange the bytes in the right
174 * order. (This also works on machines of unknown byte order.)
175 */
176 dbus_uint32_t X[16];
177 const unsigned char *xp = data;
178 int i;
179
180 for (i = 0; i < 16; ++i, xp += 4)
181 X[i] = xp[0] + (xp[1] << 8) + (xp[2] << 16) + (xp[3] << 24);
182
183 #else /* !WORDS_BIGENDIAN */
184 /*
185 * On little-endian machines, we can process properly aligned data
186 * without copying it.
187 */
188 dbus_uint32_t xbuf[16];
189 const dbus_uint32_t *X;
190
191 if (!((data - (const unsigned char *)0) & 3))
192 {
193 /* data are properly aligned */
194 X = (const dbus_uint32_t *)data;
195 }
196 else
197 {
198 /* not aligned */
199 memcpy(xbuf, data, 64);
200 X = xbuf;
201 }
202 #endif
203
204 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
205
206 /* Round 1. */
207 /* Let [abcd k s i] denote the operation
208 a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
209 #define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
210 #define SET(a, b, c, d, k, s, Ti) \
211 t = a + F(b,c,d) + X[k] + Ti; \
212 a = ROTATE_LEFT(t, s) + b
213 /* Do the following 16 operations. */
214 SET(a, b, c, d, 0, 7, T1);
215 SET(d, a, b, c, 1, 12, T2);
216 SET(c, d, a, b, 2, 17, T3);
217 SET(b, c, d, a, 3, 22, T4);
218 SET(a, b, c, d, 4, 7, T5);
219 SET(d, a, b, c, 5, 12, T6);
220 SET(c, d, a, b, 6, 17, T7);
221 SET(b, c, d, a, 7, 22, T8);
222 SET(a, b, c, d, 8, 7, T9);
223 SET(d, a, b, c, 9, 12, T10);
224 SET(c, d, a, b, 10, 17, T11);
225 SET(b, c, d, a, 11, 22, T12);
226 SET(a, b, c, d, 12, 7, T13);
227 SET(d, a, b, c, 13, 12, T14);
228 SET(c, d, a, b, 14, 17, T15);
229 SET(b, c, d, a, 15, 22, T16);
230 #undef SET
231
232 /* Round 2. */
233 /* Let [abcd k s i] denote the operation
234 a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */
235 #define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
236 #define SET(a, b, c, d, k, s, Ti) \
237 t = a + G(b,c,d) + X[k] + Ti; \
238 a = ROTATE_LEFT(t, s) + b
239 /* Do the following 16 operations. */
240 SET(a, b, c, d, 1, 5, T17);
241 SET(d, a, b, c, 6, 9, T18);
242 SET(c, d, a, b, 11, 14, T19);
243 SET(b, c, d, a, 0, 20, T20);
244 SET(a, b, c, d, 5, 5, T21);
245 SET(d, a, b, c, 10, 9, T22);
246 SET(c, d, a, b, 15, 14, T23);
247 SET(b, c, d, a, 4, 20, T24);
248 SET(a, b, c, d, 9, 5, T25);
249 SET(d, a, b, c, 14, 9, T26);
250 SET(c, d, a, b, 3, 14, T27);
251 SET(b, c, d, a, 8, 20, T28);
252 SET(a, b, c, d, 13, 5, T29);
253 SET(d, a, b, c, 2, 9, T30);
254 SET(c, d, a, b, 7, 14, T31);
255 SET(b, c, d, a, 12, 20, T32);
256 #undef SET
257
258 /* Round 3. */
259 /* Let [abcd k s t] denote the operation
260 a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */
261 #define H(x, y, z) ((x) ^ (y) ^ (z))
262 #define SET(a, b, c, d, k, s, Ti) \
263 t = a + H(b,c,d) + X[k] + Ti; \
264 a = ROTATE_LEFT(t, s) + b
265 /* Do the following 16 operations. */
266 SET(a, b, c, d, 5, 4, T33);
267 SET(d, a, b, c, 8, 11, T34);
268 SET(c, d, a, b, 11, 16, T35);
269 SET(b, c, d, a, 14, 23, T36);
270 SET(a, b, c, d, 1, 4, T37);
271 SET(d, a, b, c, 4, 11, T38);
272 SET(c, d, a, b, 7, 16, T39);
273 SET(b, c, d, a, 10, 23, T40);
274 SET(a, b, c, d, 13, 4, T41);
275 SET(d, a, b, c, 0, 11, T42);
276 SET(c, d, a, b, 3, 16, T43);
277 SET(b, c, d, a, 6, 23, T44);
278 SET(a, b, c, d, 9, 4, T45);
279 SET(d, a, b, c, 12, 11, T46);
280 SET(c, d, a, b, 15, 16, T47);
281 SET(b, c, d, a, 2, 23, T48);
282 #undef SET
283
284 /* Round 4. */
285 /* Let [abcd k s t] denote the operation
286 a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */
287 #define I(x, y, z) ((y) ^ ((x) | ~(z)))
288 #define SET(a, b, c, d, k, s, Ti) \
289 t = a + I(b,c,d) + X[k] + Ti; \
290 a = ROTATE_LEFT(t, s) + b
291 /* Do the following 16 operations. */
292 SET(a, b, c, d, 0, 6, T49);
293 SET(d, a, b, c, 7, 10, T50);
294 SET(c, d, a, b, 14, 15, T51);
295 SET(b, c, d, a, 5, 21, T52);
296 SET(a, b, c, d, 12, 6, T53);
297 SET(d, a, b, c, 3, 10, T54);
298 SET(c, d, a, b, 10, 15, T55);
299 SET(b, c, d, a, 1, 21, T56);
300 SET(a, b, c, d, 8, 6, T57);
301 SET(d, a, b, c, 15, 10, T58);
302 SET(c, d, a, b, 6, 15, T59);
303 SET(b, c, d, a, 13, 21, T60);
304 SET(a, b, c, d, 4, 6, T61);
305 SET(d, a, b, c, 11, 10, T62);
306 SET(c, d, a, b, 2, 15, T63);
307 SET(b, c, d, a, 9, 21, T64);
308 #undef SET
309
310 /* Then perform the following additions. (That is increment each
311 of the four registers by the value it had before this block
312 was started.) */
313 context->abcd[0] += a;
314 context->abcd[1] += b;
315 context->abcd[2] += c;
316 context->abcd[3] += d;
317 }
318
319 static void
md5_init(DBusMD5Context * context)320 md5_init (DBusMD5Context *context)
321 {
322 context->count[0] = context->count[1] = 0;
323 context->abcd[0] = 0x67452301;
324 context->abcd[1] = /*0xefcdab89*/ T_MASK ^ 0x10325476;
325 context->abcd[2] = /*0x98badcfe*/ T_MASK ^ 0x67452301;
326 context->abcd[3] = 0x10325476;
327 }
328
329 static void
md5_append(DBusMD5Context * context,const unsigned char * data,int nbytes)330 md5_append (DBusMD5Context *context, const unsigned char *data, int nbytes)
331 {
332 const unsigned char *p = data;
333 int left = nbytes;
334 int offset = (context->count[0] >> 3) & 63;
335 dbus_uint32_t nbits = (dbus_uint32_t)(nbytes << 3);
336
337 if (nbytes <= 0)
338 return;
339
340 /* Update the message length. */
341 context->count[1] += nbytes >> 29;
342 context->count[0] += nbits;
343 if (context->count[0] < nbits)
344 context->count[1]++;
345
346 /* Process an initial partial block. */
347 if (offset)
348 {
349 int copy = (offset + nbytes > 64 ? 64 - offset : nbytes);
350
351 memcpy(context->buf + offset, p, copy);
352 if (offset + copy < 64)
353 return;
354 p += copy;
355 left -= copy;
356 md5_process(context, context->buf);
357 }
358
359 /* Process full blocks. */
360 for (; left >= 64; p += 64, left -= 64)
361 md5_process(context, p);
362
363 /* Process a final partial block. */
364 if (left)
365 memcpy(context->buf, p, left);
366 }
367
368 static void
md5_finish(DBusMD5Context * context,unsigned char digest[16])369 md5_finish (DBusMD5Context *context, unsigned char digest[16])
370 {
371 static const unsigned char pad[64] = {
372 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
373 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
374 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
375 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
376 };
377 unsigned char data[8];
378 int i;
379
380 /* Save the length before padding. */
381 for (i = 0; i < 8; ++i)
382 data[i] = (unsigned char)(context->count[i >> 2] >> ((i & 3) << 3));
383 /* Pad to 56 bytes mod 64. */
384 md5_append(context, pad, ((55 - (context->count[0] >> 3)) & 63) + 1);
385 /* Append the length. */
386 md5_append(context, data, 8);
387 for (i = 0; i < 16; ++i)
388 digest[i] = (unsigned char)(context->abcd[i >> 2] >> ((i & 3) << 3));
389 }
390
391 /** @} */ /* End of internals */
392
393 /**
394 * @addtogroup DBusMD5
395 *
396 * @{
397 */
398
399 /**
400 * Initializes the MD5 context.
401 *
402 * @param context an uninitialized context, typically on the stack.
403 */
404 void
_dbus_md5_init(DBusMD5Context * context)405 _dbus_md5_init (DBusMD5Context *context)
406 {
407 md5_init (context);
408 }
409
410
411 /**
412 * Feeds more data into an existing md5sum computation.
413 *
414 * @param context the MD5 context
415 * @param data the additional data to hash
416 */
417 void
_dbus_md5_update(DBusMD5Context * context,const DBusString * data)418 _dbus_md5_update (DBusMD5Context *context,
419 const DBusString *data)
420 {
421 unsigned int inputLen;
422 unsigned char *input;
423
424 _dbus_string_get_const_data (data, (const char**) &input);
425 inputLen = _dbus_string_get_length (data);
426
427 md5_append (context, input, inputLen);
428 }
429
430 /**
431 * MD5 finalization. Ends an MD5 message-digest operation, writing the
432 * the message digest and zeroing the context. The results are
433 * returned as a raw 16-byte digest, not as the ascii-hex-digits
434 * string form of the digest.
435 *
436 * @param context the MD5 context
437 * @param results string to append the 16-byte MD5 digest to
438 * @returns #FALSE if not enough memory to append the digest
439 *
440 */
441 dbus_bool_t
_dbus_md5_final(DBusMD5Context * context,DBusString * results)442 _dbus_md5_final (DBusMD5Context *context,
443 DBusString *results)
444 {
445 unsigned char digest[16];
446
447 md5_finish (context, digest);
448
449 if (!_dbus_string_append_len (results, digest, 16))
450 return FALSE;
451
452 /* some kind of security paranoia, though it seems pointless
453 * to me given the nonzeroed stuff flying around
454 */
455 _DBUS_ZERO(*context);
456
457 return TRUE;
458 }
459
460 /**
461 * Computes the ASCII hex-encoded md5sum of the given data and
462 * appends it to the output string.
463 *
464 * @param data input data to be hashed
465 * @param ascii_output string to append ASCII md5sum to
466 * @returns #FALSE if not enough memory
467 */
468 dbus_bool_t
_dbus_md5_compute(const DBusString * data,DBusString * ascii_output)469 _dbus_md5_compute (const DBusString *data,
470 DBusString *ascii_output)
471 {
472 DBusMD5Context context;
473 DBusString digest;
474
475 _dbus_md5_init (&context);
476
477 _dbus_md5_update (&context, data);
478
479 if (!_dbus_string_init (&digest))
480 return FALSE;
481
482 if (!_dbus_md5_final (&context, &digest))
483 goto error;
484
485 if (!_dbus_string_hex_encode (&digest, 0, ascii_output,
486 _dbus_string_get_length (ascii_output)))
487 goto error;
488
489 _dbus_string_free (&digest);
490
491 return TRUE;
492
493 error:
494 _dbus_string_free (&digest);
495 return FALSE;
496 }
497
498 /** @} */ /* end of exported functions */
499
500 #ifdef DBUS_BUILD_TESTS
501 #include "dbus-test.h"
502 #include <stdio.h>
503
504 static dbus_bool_t
check_md5_binary(const unsigned char * input,int input_len,const char * expected)505 check_md5_binary (const unsigned char *input,
506 int input_len,
507 const char *expected)
508 {
509 DBusString input_str;
510 DBusString expected_str;
511 DBusString results;
512
513 _dbus_string_init_const_len (&input_str, input, input_len);
514 _dbus_string_init_const (&expected_str, expected);
515
516 if (!_dbus_string_init (&results))
517 _dbus_assert_not_reached ("no memory for md5 results");
518
519 if (!_dbus_md5_compute (&input_str, &results))
520 _dbus_assert_not_reached ("no memory for md5 results");
521
522 if (!_dbus_string_equal (&expected_str, &results))
523 {
524 const char *s;
525 _dbus_string_get_const_data (&results, &s);
526 _dbus_warn ("Expected hash %s got %s for md5 sum\n",
527 expected, s);
528 _dbus_string_free (&results);
529 return FALSE;
530 }
531
532 _dbus_string_free (&results);
533 return TRUE;
534 }
535
536 static dbus_bool_t
check_md5_str(const char * input,const char * expected)537 check_md5_str (const char *input,
538 const char *expected)
539 {
540 return check_md5_binary (input, strlen (input), expected);
541 }
542
543 /**
544 * @ingroup DBusMD5Internals
545 * Unit test for MD5 computation.
546 *
547 * @returns #TRUE on success.
548 */
549 dbus_bool_t
_dbus_md5_test(void)550 _dbus_md5_test (void)
551 {
552 unsigned char all_bytes[256];
553 int i;
554
555 i = 0;
556 while (i < 256)
557 {
558 all_bytes[i] = i;
559 ++i;
560 }
561
562 if (!check_md5_binary (all_bytes, 256,
563 "e2c865db4162bed963bfaa9ef6ac18f0"))
564 return FALSE;
565
566 #define CHECK(input,expected) if (!check_md5_str (input, expected)) return FALSE
567
568 CHECK ("", "d41d8cd98f00b204e9800998ecf8427e");
569 CHECK ("a", "0cc175b9c0f1b6a831c399e269772661");
570 CHECK ("abc", "900150983cd24fb0d6963f7d28e17f72");
571 CHECK ("message digest", "f96b697d7cb7938d525a2f31aaf161d0");
572 CHECK ("abcdefghijklmnopqrstuvwxyz", "c3fcd3d76192e4007dfb496cca67e13b");
573 CHECK ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
574 "d174ab98d277d9f5a5611c2c9f419d9f");
575 CHECK ("12345678901234567890123456789012345678901234567890123456789012345678901234567890",
576 "57edf4a22be3c955ac49da2e2107b67a");
577
578 return TRUE;
579 }
580
581 #endif /* DBUS_BUILD_TESTS */
582