source: trunk/server/libcli/auth/ntlm_check.c

Last change on this file was 752, checked in by Silvan Scherrer, 13 years ago

Samba Server: updated trunk to 3.6.9 2nd part
File size: 20.2 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 Password and authentication handling
4 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2004
5 Copyright (C) Gerald Carter 2003
6 Copyright (C) Luke Kenneth Casson Leighton 1996-2000
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
20*/
21
22#include "includes.h"
23#include "../lib/crypto/crypto.h"
24#include "librpc/gen_ndr/netlogon.h"
25#include "libcli/auth/libcli_auth.h"
26
27/****************************************************************************
28 Core of smb password checking routine.
29****************************************************************************/
30
31static bool smb_pwd_check_ntlmv1(TALLOC_CTX *mem_ctx,
32 const DATA_BLOB *nt_response,
33 const uint8_t *part_passwd,
34 const DATA_BLOB *sec_blob,
35 DATA_BLOB *user_sess_key)
36{
37 /* Finish the encryption of part_passwd. */
38 uint8_t p24[24];
39
40 if (part_passwd == NULL) {
41 DEBUG(10,("No password set - DISALLOWING access\n"));
42 /* No password set - always false ! */
43 return false;
44 }
45
46 if (sec_blob->length != 8) {
47 DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect challenge size (%lu)\n",
48 (unsigned long)sec_blob->length));
49 return false;
50 }
51
52 if (nt_response->length != 24) {
53 DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect password length (%lu)\n",
54 (unsigned long)nt_response->length));
55 return false;
56 }
57
58 SMBOWFencrypt(part_passwd, sec_blob->data, p24);
59
60#if DEBUG_PASSWORD
61 DEBUG(100,("Part password (P16) was |\n"));
62 dump_data(100, part_passwd, 16);
63 DEBUGADD(100,("Password from client was |\n"));
64 dump_data(100, nt_response->data, nt_response->length);
65 DEBUGADD(100,("Given challenge was |\n"));
66 dump_data(100, sec_blob->data, sec_blob->length);
67 DEBUGADD(100,("Value from encryption was |\n"));
68 dump_data(100, p24, 24);
69#endif
70 if (memcmp(p24, nt_response->data, 24) == 0) {
71 if (user_sess_key != NULL) {
72 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
73 SMBsesskeygen_ntv1(part_passwd, user_sess_key->data);
74 }
75 return true;
76 }
77 return false;
78}
79
80/****************************************************************************
81 Core of smb password checking routine. (NTLMv2, LMv2)
82 Note: The same code works with both NTLMv2 and LMv2.
83****************************************************************************/
84
85static bool smb_pwd_check_ntlmv2(TALLOC_CTX *mem_ctx,
86 const DATA_BLOB *ntv2_response,
87 const uint8_t *part_passwd,
88 const DATA_BLOB *sec_blob,
89 const char *user, const char *domain,
90 DATA_BLOB *user_sess_key)
91{
92 /* Finish the encryption of part_passwd. */
93 uint8_t kr[16];
94 uint8_t value_from_encryption[16];
95 DATA_BLOB client_key_data;
96
97 if (part_passwd == NULL) {
98 DEBUG(10,("No password set - DISALLOWING access\n"));
99 /* No password set - always false */
100 return false;
101 }
102
103 if (sec_blob->length != 8) {
104 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
105 (unsigned long)sec_blob->length));
106 return false;
107 }
108
109 if (ntv2_response->length < 24) {
110 /* We MUST have more than 16 bytes, or the stuff below will go
111 crazy. No known implementation sends less than the 24 bytes
112 for LMv2, let alone NTLMv2. */
113 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
114 (unsigned long)ntv2_response->length));
115 return false;
116 }
117
118 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
119 /*
120 todo: should we be checking this for anything? We can't for LMv2,
121 but for NTLMv2 it is meant to contain the current time etc.
122 */
123
124 if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
125 return false;
126 }
127
128 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
129
130#if DEBUG_PASSWORD
131 DEBUG(100,("Part password (P16) was |\n"));
132 dump_data(100, part_passwd, 16);
133 DEBUGADD(100,("Password from client was |\n"));
134 dump_data(100, ntv2_response->data, ntv2_response->length);
135 DEBUGADD(100,("Variable data from client was |\n"));
136 dump_data(100, client_key_data.data, client_key_data.length);
137 DEBUGADD(100,("Given challenge was |\n"));
138 dump_data(100, sec_blob->data, sec_blob->length);
139 DEBUGADD(100,("Value from encryption was |\n"));
140 dump_data(100, value_from_encryption, 16);
141#endif
142 data_blob_clear_free(&client_key_data);
143 if (memcmp(value_from_encryption, ntv2_response->data, 16) == 0) {
144 if (user_sess_key != NULL) {
145 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
146 SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
147 }
148 return true;
149 }
150 return false;
151}
152
153/****************************************************************************
154 Core of smb password checking routine. (NTLMv2, LMv2)
155 Note: The same code works with both NTLMv2 and LMv2.
156****************************************************************************/
157
158static bool smb_sess_key_ntlmv2(TALLOC_CTX *mem_ctx,
159 const DATA_BLOB *ntv2_response,
160 const uint8_t *part_passwd,
161 const DATA_BLOB *sec_blob,
162 const char *user, const char *domain,
163 DATA_BLOB *user_sess_key)
164{
165 /* Finish the encryption of part_passwd. */
166 uint8_t kr[16];
167 uint8_t value_from_encryption[16];
168 DATA_BLOB client_key_data;
169
170 if (part_passwd == NULL) {
171 DEBUG(10,("No password set - DISALLOWING access\n"));
172 /* No password set - always false */
173 return false;
174 }
175
176 if (sec_blob->length != 8) {
177 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect challenge size (%lu)\n",
178 (unsigned long)sec_blob->length));
179 return false;
180 }
181
182 if (ntv2_response->length < 24) {
183 /* We MUST have more than 16 bytes, or the stuff below will go
184 crazy. No known implementation sends less than the 24 bytes
185 for LMv2, let alone NTLMv2. */
186 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect password length (%lu)\n",
187 (unsigned long)ntv2_response->length));
188 return false;
189 }
190
191 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
192
193 if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
194 return false;
195 }
196
197 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
198 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
199 SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
200 return true;
201}
202
203/**
204 * Compare password hashes against those from the SAM
205 *
206 * @param mem_ctx talloc context
207 * @param client_lanman LANMAN password hash, as supplied by the client
208 * @param client_nt NT (MD4) password hash, as supplied by the client
209 * @param username internal Samba username, for log messages
210 * @param client_username username the client used
211 * @param client_domain domain name the client used (may be mapped)
212 * @param stored_lanman LANMAN password hash, as stored on the SAM
213 * @param stored_nt NT (MD4) password hash, as stored on the SAM
214 * @param user_sess_key User session key
215 * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
216 */
217
218NTSTATUS hash_password_check(TALLOC_CTX *mem_ctx,
219 bool lanman_auth,
220 const struct samr_Password *client_lanman,
221 const struct samr_Password *client_nt,
222 const char *username,
223 const struct samr_Password *stored_lanman,
224 const struct samr_Password *stored_nt)
225{
226 if (stored_nt == NULL) {
227 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
228 username));
229 }
230
231 if (client_nt && stored_nt) {
232 if (memcmp(client_nt->hash, stored_nt->hash, sizeof(stored_nt->hash)) == 0) {
233 return NT_STATUS_OK;
234 } else {
235 DEBUG(3,("ntlm_password_check: Interactive logon: NT password check failed for user %s\n",
236 username));
237 return NT_STATUS_WRONG_PASSWORD;
238 }
239
240 } else if (client_lanman && stored_lanman) {
241 if (!lanman_auth) {
242 DEBUG(3,("ntlm_password_check: Interactive logon: only LANMAN password supplied for user %s, and LM passwords are disabled!\n",
243 username));
244 return NT_STATUS_WRONG_PASSWORD;
245 }
246 if (strchr_m(username, '@')) {
247 return NT_STATUS_NOT_FOUND;
248 }
249
250 if (memcmp(client_lanman->hash, stored_lanman->hash, sizeof(stored_lanman->hash)) == 0) {
251 return NT_STATUS_OK;
252 } else {
253 DEBUG(3,("ntlm_password_check: Interactive logon: LANMAN password check failed for user %s\n",
254 username));
255 return NT_STATUS_WRONG_PASSWORD;
256 }
257 }
258 if (strchr_m(username, '@')) {
259 return NT_STATUS_NOT_FOUND;
260 }
261 return NT_STATUS_WRONG_PASSWORD;
262}
263
264/**
265 * Check a challenge-response password against the value of the NT or
266 * LM password hash.
267 *
268 * @param mem_ctx talloc context
269 * @param challenge 8-byte challenge. If all zero, forces plaintext comparison
270 * @param nt_response 'unicode' NT response to the challenge, or unicode password
271 * @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
272 * @param username internal Samba username, for log messages
273 * @param client_username username the client used
274 * @param client_domain domain name the client used (may be mapped)
275 * @param stored_lanman LANMAN ASCII password from our passdb or similar
276 * @param stored_nt MD4 unicode password from our passdb or similar
277 * @param user_sess_key User session key
278 * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
279 */
280
281NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
282 bool lanman_auth,
283 bool ntlm_auth,
284 uint32_t logon_parameters,
285 const DATA_BLOB *challenge,
286 const DATA_BLOB *lm_response,
287 const DATA_BLOB *nt_response,
288 const char *username,
289 const char *client_username,
290 const char *client_domain,
291 const struct samr_Password *stored_lanman,
292 const struct samr_Password *stored_nt,
293 DATA_BLOB *user_sess_key,
294 DATA_BLOB *lm_sess_key)
295{
296 const static uint8_t zeros[8];
297 DATA_BLOB tmp_sess_key;
298 const char *upper_client_domain = NULL;
299
300 if (client_domain != NULL) {
301 upper_client_domain = talloc_strdup_upper(mem_ctx, client_domain);
302 if (upper_client_domain == NULL) {
303 return NT_STATUS_NO_MEMORY;
304 }
305 }
306
307 if (stored_nt == NULL) {
308 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
309 username));
310 }
311
312 *lm_sess_key = data_blob(NULL, 0);
313 *user_sess_key = data_blob(NULL, 0);
314
315 /* Check for cleartext netlogon. Used by Exchange 5.5. */
316 if ((logon_parameters & MSV1_0_CLEARTEXT_PASSWORD_ALLOWED)
317 && challenge->length == sizeof(zeros)
318 && (memcmp(challenge->data, zeros, challenge->length) == 0 )) {
319 struct samr_Password client_nt;
320 struct samr_Password client_lm;
321 char *unix_pw = NULL;
322 bool lm_ok;
323
324 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
325 username));
326 mdfour(client_nt.hash, nt_response->data, nt_response->length);
327
328 if (lm_response->length &&
329 (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
330 lm_response->data, lm_response->length,
331 (void *)&unix_pw, NULL, false))) {
332 if (E_deshash(unix_pw, client_lm.hash)) {
333 lm_ok = true;
334 } else {
335 lm_ok = false;
336 }
337 } else {
338 lm_ok = false;
339 }
340 return hash_password_check(mem_ctx,
341 lanman_auth,
342 lm_ok ? &client_lm : NULL,
343 nt_response->length ? &client_nt : NULL,
344 username,
345 stored_lanman, stored_nt);
346 }
347
348 if (nt_response->length != 0 && nt_response->length < 24) {
349 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
350 (unsigned long)nt_response->length, username));
351 }
352
353 if (nt_response->length > 24 && stored_nt) {
354 /* We have the NT MD4 hash challenge available - see if we can
355 use it
356 */
357 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n",
358 client_domain ? client_domain : "<NULL>"));
359 if (smb_pwd_check_ntlmv2(mem_ctx,
360 nt_response,
361 stored_nt->hash, challenge,
362 client_username,
363 client_domain,
364 user_sess_key)) {
365 if (user_sess_key->length) {
366 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
367 }
368 return NT_STATUS_OK;
369 }
370
371 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n",
372 upper_client_domain ? upper_client_domain : "<NULL>"));
373 if (smb_pwd_check_ntlmv2(mem_ctx,
374 nt_response,
375 stored_nt->hash, challenge,
376 client_username,
377 upper_client_domain,
378 user_sess_key)) {
379 if (user_sess_key->length) {
380 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
381 }
382 return NT_STATUS_OK;
383 }
384
385 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
386 if (smb_pwd_check_ntlmv2(mem_ctx,
387 nt_response,
388 stored_nt->hash, challenge,
389 client_username,
390 "",
391 user_sess_key)) {
392 if (user_sess_key->length) {
393 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
394 }
395 return NT_STATUS_OK;
396 } else {
397 DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
398 }
399 } else if (nt_response->length == 24 && stored_nt) {
400 if (ntlm_auth) {
401 /* We have the NT MD4 hash challenge available - see if we can
402 use it (ie. does it exist in the smbpasswd file).
403 */
404 DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
405 if (smb_pwd_check_ntlmv1(mem_ctx,
406 nt_response,
407 stored_nt->hash, challenge,
408 user_sess_key)) {
409 /* The LM session key for this response is not very secure,
410 so use it only if we otherwise allow LM authentication */
411
412 if (lanman_auth && stored_lanman) {
413 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
414 }
415 return NT_STATUS_OK;
416 } else {
417 DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
418 username));
419 return NT_STATUS_WRONG_PASSWORD;
420 }
421 } else {
422 DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
423 username));
424 /* no return, because we might pick up LMv2 in the LM field */
425 }
426 }
427
428 if (lm_response->length == 0) {
429 DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
430 username));
431 return NT_STATUS_WRONG_PASSWORD;
432 }
433
434 if (lm_response->length < 24) {
435 DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
436 (unsigned long)nt_response->length, username));
437 return NT_STATUS_WRONG_PASSWORD;
438 }
439
440 if (!lanman_auth) {
441 DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
442 username));
443 } else if (!stored_lanman) {
444 DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
445 username));
446 } else if (strchr_m(username, '@')) {
447 DEBUG(3,("ntlm_password_check: NO LanMan password allowed for username@realm logins (user: %s)\n",
448 username));
449 } else {
450 DEBUG(4,("ntlm_password_check: Checking LM password\n"));
451 if (smb_pwd_check_ntlmv1(mem_ctx,
452 lm_response,
453 stored_lanman->hash, challenge,
454 NULL)) {
455 /* The session key for this response is still very odd.
456 It not very secure, so use it only if we otherwise
457 allow LM authentication */
458
459 if (lanman_auth && stored_lanman) {
460 uint8_t first_8_lm_hash[16];
461 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
462 memset(first_8_lm_hash + 8, '\0', 8);
463 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
464 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
465 }
466 return NT_STATUS_OK;
467 }
468 }
469
470 if (!stored_nt) {
471 DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
472 return NT_STATUS_WRONG_PASSWORD;
473 }
474
475 /* This is for 'LMv2' authentication. almost NTLMv2 but limited to 24 bytes.
476 - related to Win9X, legacy NAS pass-though authentication
477 */
478 DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n",
479 client_domain ? client_domain : "<NULL>"));
480 if (smb_pwd_check_ntlmv2(mem_ctx,
481 lm_response,
482 stored_nt->hash, challenge,
483 client_username,
484 client_domain,
485 &tmp_sess_key)) {
486 if (nt_response->length > 24) {
487 /* If NTLMv2 authentication has preceeded us
488 * (even if it failed), then use the session
489 * key from that. See the RPC-SAMLOGON
490 * torture test */
491 smb_sess_key_ntlmv2(mem_ctx,
492 nt_response,
493 stored_nt->hash, challenge,
494 client_username,
495 client_domain,
496 user_sess_key);
497 } else {
498 /* Otherwise, use the LMv2 session key */
499 *user_sess_key = tmp_sess_key;
500 }
501 if (user_sess_key->length) {
502 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
503 }
504 return NT_STATUS_OK;
505 }
506
507 DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n",
508 upper_client_domain ? upper_client_domain : "<NULL>"));
509 if (smb_pwd_check_ntlmv2(mem_ctx,
510 lm_response,
511 stored_nt->hash, challenge,
512 client_username,
513 upper_client_domain,
514 &tmp_sess_key)) {
515 if (nt_response->length > 24) {
516 /* If NTLMv2 authentication has preceeded us
517 * (even if it failed), then use the session
518 * key from that. See the RPC-SAMLOGON
519 * torture test */
520 smb_sess_key_ntlmv2(mem_ctx,
521 nt_response,
522 stored_nt->hash, challenge,
523 client_username,
524 upper_client_domain,
525 user_sess_key);
526 } else {
527 /* Otherwise, use the LMv2 session key */
528 *user_sess_key = tmp_sess_key;
529 }
530 if (user_sess_key->length) {
531 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
532 }
533 return NT_STATUS_OK;
534 }
535
536 DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
537 if (smb_pwd_check_ntlmv2(mem_ctx,
538 lm_response,
539 stored_nt->hash, challenge,
540 client_username,
541 "",
542 &tmp_sess_key)) {
543 if (nt_response->length > 24) {
544 /* If NTLMv2 authentication has preceeded us
545 * (even if it failed), then use the session
546 * key from that. See the RPC-SAMLOGON
547 * torture test */
548 smb_sess_key_ntlmv2(mem_ctx,
549 nt_response,
550 stored_nt->hash, challenge,
551 client_username,
552 "",
553 user_sess_key);
554 } else {
555 /* Otherwise, use the LMv2 session key */
556 *user_sess_key = tmp_sess_key;
557 }
558 if (user_sess_key->length) {
559 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
560 }
561 return NT_STATUS_OK;
562 }
563
564 /* Apparently NT accepts NT responses in the LM field
565 - I think this is related to Win9X pass-though authentication
566 */
567 DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
568 if (ntlm_auth) {
569 if (smb_pwd_check_ntlmv1(mem_ctx,
570 lm_response,
571 stored_nt->hash, challenge,
572 NULL)) {
573 /* The session key for this response is still very odd.
574 It not very secure, so use it only if we otherwise
575 allow LM authentication */
576
577 if (lanman_auth && stored_lanman) {
578 uint8_t first_8_lm_hash[16];
579 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
580 memset(first_8_lm_hash + 8, '\0', 8);
581 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
582 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
583 }
584 return NT_STATUS_OK;
585 }
586 DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
587 } else {
588 DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
589 }
590
591 /* Try and match error codes */
592 if (strchr_m(username, '@')) {
593 return NT_STATUS_NOT_FOUND;
594 }
595 return NT_STATUS_WRONG_PASSWORD;
596}
597
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