source: vendor/3.5.0/libcli/auth/ntlm_check.c

Last change on this file was 414, checked in by Herwig Bauernfeind, 15 years ago

Samba 3.5.0: Initial import
File size: 19.6 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 bool upper_case_domain, /* should the domain be transformed into upper case? */
91 DATA_BLOB *user_sess_key)
92{
93 /* Finish the encryption of part_passwd. */
94 uint8_t kr[16];
95 uint8_t value_from_encryption[16];
96 DATA_BLOB client_key_data;
97
98 if (part_passwd == NULL) {
99 DEBUG(10,("No password set - DISALLOWING access\n"));
100 /* No password set - always false */
101 return false;
102 }
103
104 if (sec_blob->length != 8) {
105 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
106 (unsigned long)sec_blob->length));
107 return false;
108 }
109
110 if (ntv2_response->length < 24) {
111 /* We MUST have more than 16 bytes, or the stuff below will go
112 crazy. No known implementation sends less than the 24 bytes
113 for LMv2, let alone NTLMv2. */
114 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
115 (unsigned long)ntv2_response->length));
116 return false;
117 }
118
119 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
120 /*
121 todo: should we be checking this for anything? We can't for LMv2,
122 but for NTLMv2 it is meant to contain the current time etc.
123 */
124
125 if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
126 return false;
127 }
128
129 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
130
131#if DEBUG_PASSWORD
132 DEBUG(100,("Part password (P16) was |\n"));
133 dump_data(100, part_passwd, 16);
134 DEBUGADD(100,("Password from client was |\n"));
135 dump_data(100, ntv2_response->data, ntv2_response->length);
136 DEBUGADD(100,("Variable data from client was |\n"));
137 dump_data(100, client_key_data.data, client_key_data.length);
138 DEBUGADD(100,("Given challenge was |\n"));
139 dump_data(100, sec_blob->data, sec_blob->length);
140 DEBUGADD(100,("Value from encryption was |\n"));
141 dump_data(100, value_from_encryption, 16);
142#endif
143 data_blob_clear_free(&client_key_data);
144 if (memcmp(value_from_encryption, ntv2_response->data, 16) == 0) {
145 if (user_sess_key != NULL) {
146 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
147 SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
148 }
149 return true;
150 }
151 return false;
152}
153
154/****************************************************************************
155 Core of smb password checking routine. (NTLMv2, LMv2)
156 Note: The same code works with both NTLMv2 and LMv2.
157****************************************************************************/
158
159static bool smb_sess_key_ntlmv2(TALLOC_CTX *mem_ctx,
160 const DATA_BLOB *ntv2_response,
161 const uint8_t *part_passwd,
162 const DATA_BLOB *sec_blob,
163 const char *user, const char *domain,
164 bool upper_case_domain, /* should the domain be transformed into upper case? */
165 DATA_BLOB *user_sess_key)
166{
167 /* Finish the encryption of part_passwd. */
168 uint8_t kr[16];
169 uint8_t value_from_encryption[16];
170 DATA_BLOB client_key_data;
171
172 if (part_passwd == NULL) {
173 DEBUG(10,("No password set - DISALLOWING access\n"));
174 /* No password set - always false */
175 return false;
176 }
177
178 if (sec_blob->length != 8) {
179 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect challenge size (%lu)\n",
180 (unsigned long)sec_blob->length));
181 return false;
182 }
183
184 if (ntv2_response->length < 24) {
185 /* We MUST have more than 16 bytes, or the stuff below will go
186 crazy. No known implementation sends less than the 24 bytes
187 for LMv2, let alone NTLMv2. */
188 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect password length (%lu)\n",
189 (unsigned long)ntv2_response->length));
190 return false;
191 }
192
193 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
194
195 if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
196 return false;
197 }
198
199 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
200 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
201 SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
202 return true;
203}
204
205/**
206 * Compare password hashes against those from the SAM
207 *
208 * @param mem_ctx talloc context
209 * @param client_lanman LANMAN password hash, as supplied by the client
210 * @param client_nt NT (MD4) password hash, as supplied by the client
211 * @param username internal Samba username, for log messages
212 * @param client_username username the client used
213 * @param client_domain domain name the client used (may be mapped)
214 * @param stored_lanman LANMAN password hash, as stored on the SAM
215 * @param stored_nt NT (MD4) password hash, as stored on the SAM
216 * @param user_sess_key User session key
217 * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
218 */
219
220NTSTATUS hash_password_check(TALLOC_CTX *mem_ctx,
221 bool lanman_auth,
222 const struct samr_Password *client_lanman,
223 const struct samr_Password *client_nt,
224 const char *username,
225 const struct samr_Password *stored_lanman,
226 const struct samr_Password *stored_nt)
227{
228 if (stored_nt == NULL) {
229 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
230 username));
231 }
232
233 if (client_nt && stored_nt) {
234 if (memcmp(client_nt->hash, stored_nt->hash, sizeof(stored_nt->hash)) == 0) {
235 return NT_STATUS_OK;
236 } else {
237 DEBUG(3,("ntlm_password_check: Interactive logon: NT password check failed for user %s\n",
238 username));
239 return NT_STATUS_WRONG_PASSWORD;
240 }
241
242 } else if (client_lanman && stored_lanman) {
243 if (!lanman_auth) {
244 DEBUG(3,("ntlm_password_check: Interactive logon: only LANMAN password supplied for user %s, and LM passwords are disabled!\n",
245 username));
246 return NT_STATUS_WRONG_PASSWORD;
247 }
248 if (strchr_m(username, '@')) {
249 return NT_STATUS_NOT_FOUND;
250 }
251
252 if (memcmp(client_lanman->hash, stored_lanman->hash, sizeof(stored_lanman->hash)) == 0) {
253 return NT_STATUS_OK;
254 } else {
255 DEBUG(3,("ntlm_password_check: Interactive logon: LANMAN password check failed for user %s\n",
256 username));
257 return NT_STATUS_WRONG_PASSWORD;
258 }
259 }
260 if (strchr_m(username, '@')) {
261 return NT_STATUS_NOT_FOUND;
262 }
263 return NT_STATUS_WRONG_PASSWORD;
264}
265
266/**
267 * Check a challenge-response password against the value of the NT or
268 * LM password hash.
269 *
270 * @param mem_ctx talloc context
271 * @param challenge 8-byte challenge. If all zero, forces plaintext comparison
272 * @param nt_response 'unicode' NT response to the challenge, or unicode password
273 * @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
274 * @param username internal Samba username, for log messages
275 * @param client_username username the client used
276 * @param client_domain domain name the client used (may be mapped)
277 * @param stored_lanman LANMAN ASCII password from our passdb or similar
278 * @param stored_nt MD4 unicode password from our passdb or similar
279 * @param user_sess_key User session key
280 * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
281 */
282
283NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
284 bool lanman_auth,
285 bool ntlm_auth,
286 uint32_t logon_parameters,
287 const DATA_BLOB *challenge,
288 const DATA_BLOB *lm_response,
289 const DATA_BLOB *nt_response,
290 const char *username,
291 const char *client_username,
292 const char *client_domain,
293 const struct samr_Password *stored_lanman,
294 const struct samr_Password *stored_nt,
295 DATA_BLOB *user_sess_key,
296 DATA_BLOB *lm_sess_key)
297{
298 const static uint8_t zeros[8];
299 DATA_BLOB tmp_sess_key;
300
301 if (stored_nt == NULL) {
302 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
303 username));
304 }
305
306 *lm_sess_key = data_blob(NULL, 0);
307 *user_sess_key = data_blob(NULL, 0);
308
309 /* Check for cleartext netlogon. Used by Exchange 5.5. */
310 if ((logon_parameters & MSV1_0_CLEARTEXT_PASSWORD_ALLOWED)
311 && challenge->length == sizeof(zeros)
312 && (memcmp(challenge->data, zeros, challenge->length) == 0 )) {
313 struct samr_Password client_nt;
314 struct samr_Password client_lm;
315 char *unix_pw = NULL;
316 bool lm_ok;
317
318 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
319 username));
320 mdfour(client_nt.hash, nt_response->data, nt_response->length);
321
322 if (lm_response->length &&
323 (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
324 lm_response->data, lm_response->length,
325 (void *)&unix_pw, NULL, false))) {
326 if (E_deshash(unix_pw, client_lm.hash)) {
327 lm_ok = true;
328 } else {
329 lm_ok = false;
330 }
331 } else {
332 lm_ok = false;
333 }
334 return hash_password_check(mem_ctx,
335 lanman_auth,
336 lm_ok ? &client_lm : NULL,
337 nt_response->length ? &client_nt : NULL,
338 username,
339 stored_lanman, stored_nt);
340 }
341
342 if (nt_response->length != 0 && nt_response->length < 24) {
343 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
344 (unsigned long)nt_response->length, username));
345 }
346
347 if (nt_response->length > 24 && stored_nt) {
348 /* We have the NT MD4 hash challenge available - see if we can
349 use it
350 */
351 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n", client_domain));
352 if (smb_pwd_check_ntlmv2(mem_ctx,
353 nt_response,
354 stored_nt->hash, challenge,
355 client_username,
356 client_domain,
357 false,
358 user_sess_key)) {
359 if (user_sess_key->length) {
360 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
361 }
362 return NT_STATUS_OK;
363 }
364
365 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n", client_domain));
366 if (smb_pwd_check_ntlmv2(mem_ctx,
367 nt_response,
368 stored_nt->hash, challenge,
369 client_username,
370 client_domain,
371 true,
372 user_sess_key)) {
373 if (user_sess_key->length) {
374 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
375 }
376 return NT_STATUS_OK;
377 }
378
379 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
380 if (smb_pwd_check_ntlmv2(mem_ctx,
381 nt_response,
382 stored_nt->hash, challenge,
383 client_username,
384 "",
385 false,
386 user_sess_key)) {
387 if (user_sess_key->length) {
388 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
389 }
390 return NT_STATUS_OK;
391 } else {
392 DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
393 }
394 } else if (nt_response->length == 24 && stored_nt) {
395 if (ntlm_auth) {
396 /* We have the NT MD4 hash challenge available - see if we can
397 use it (ie. does it exist in the smbpasswd file).
398 */
399 DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
400 if (smb_pwd_check_ntlmv1(mem_ctx,
401 nt_response,
402 stored_nt->hash, challenge,
403 user_sess_key)) {
404 /* The LM session key for this response is not very secure,
405 so use it only if we otherwise allow LM authentication */
406
407 if (lanman_auth && stored_lanman) {
408 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
409 }
410 return NT_STATUS_OK;
411 } else {
412 DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
413 username));
414 return NT_STATUS_WRONG_PASSWORD;
415 }
416 } else {
417 DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
418 username));
419 /* no return, becouse we might pick up LMv2 in the LM field */
420 }
421 }
422
423 if (lm_response->length == 0) {
424 DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
425 username));
426 return NT_STATUS_WRONG_PASSWORD;
427 }
428
429 if (lm_response->length < 24) {
430 DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
431 (unsigned long)nt_response->length, username));
432 return NT_STATUS_WRONG_PASSWORD;
433 }
434
435 if (!lanman_auth) {
436 DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
437 username));
438 } else if (!stored_lanman) {
439 DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
440 username));
441 } else if (strchr_m(username, '@')) {
442 DEBUG(3,("ntlm_password_check: NO LanMan password allowed for username@realm logins (user: %s)\n",
443 username));
444 } else {
445 DEBUG(4,("ntlm_password_check: Checking LM password\n"));
446 if (smb_pwd_check_ntlmv1(mem_ctx,
447 lm_response,
448 stored_lanman->hash, challenge,
449 NULL)) {
450 /* The session key for this response is still very odd.
451 It not very secure, so use it only if we otherwise
452 allow LM authentication */
453
454 if (lanman_auth && stored_lanman) {
455 uint8_t first_8_lm_hash[16];
456 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
457 memset(first_8_lm_hash + 8, '\0', 8);
458 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
459 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
460 }
461 return NT_STATUS_OK;
462 }
463 }
464
465 if (!stored_nt) {
466 DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
467 return NT_STATUS_WRONG_PASSWORD;
468 }
469
470 /* This is for 'LMv2' authentication. almost NTLMv2 but limited to 24 bytes.
471 - related to Win9X, legacy NAS pass-though authentication
472 */
473 DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n", client_domain));
474 if (smb_pwd_check_ntlmv2(mem_ctx,
475 lm_response,
476 stored_nt->hash, challenge,
477 client_username,
478 client_domain,
479 false,
480 &tmp_sess_key)) {
481 if (nt_response->length > 24) {
482 /* If NTLMv2 authentication has preceeded us
483 * (even if it failed), then use the session
484 * key from that. See the RPC-SAMLOGON
485 * torture test */
486 smb_sess_key_ntlmv2(mem_ctx,
487 nt_response,
488 stored_nt->hash, challenge,
489 client_username,
490 client_domain,
491 false,
492 user_sess_key);
493 } else {
494 /* Otherwise, use the LMv2 session key */
495 *user_sess_key = tmp_sess_key;
496 }
497 if (user_sess_key->length) {
498 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
499 }
500 return NT_STATUS_OK;
501 }
502
503 DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n", client_domain));
504 if (smb_pwd_check_ntlmv2(mem_ctx,
505 lm_response,
506 stored_nt->hash, challenge,
507 client_username,
508 client_domain,
509 true,
510 &tmp_sess_key)) {
511 if (nt_response->length > 24) {
512 /* If NTLMv2 authentication has preceeded us
513 * (even if it failed), then use the session
514 * key from that. See the RPC-SAMLOGON
515 * torture test */
516 smb_sess_key_ntlmv2(mem_ctx,
517 nt_response,
518 stored_nt->hash, challenge,
519 client_username,
520 client_domain,
521 true,
522 user_sess_key);
523 } else {
524 /* Otherwise, use the LMv2 session key */
525 *user_sess_key = tmp_sess_key;
526 }
527 if (user_sess_key->length) {
528 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
529 }
530 return NT_STATUS_OK;
531 }
532
533 DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
534 if (smb_pwd_check_ntlmv2(mem_ctx,
535 lm_response,
536 stored_nt->hash, challenge,
537 client_username,
538 "",
539 false,
540 &tmp_sess_key)) {
541 if (nt_response->length > 24) {
542 /* If NTLMv2 authentication has preceeded us
543 * (even if it failed), then use the session
544 * key from that. See the RPC-SAMLOGON
545 * torture test */
546 smb_sess_key_ntlmv2(mem_ctx,
547 nt_response,
548 stored_nt->hash, challenge,
549 client_username,
550 "",
551 false,
552 user_sess_key);
553 } else {
554 /* Otherwise, use the LMv2 session key */
555 *user_sess_key = tmp_sess_key;
556 }
557 if (user_sess_key->length) {
558 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
559 }
560 return NT_STATUS_OK;
561 }
562
563 /* Apparently NT accepts NT responses in the LM field
564 - I think this is related to Win9X pass-though authentication
565 */
566 DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
567 if (ntlm_auth) {
568 if (smb_pwd_check_ntlmv1(mem_ctx,
569 lm_response,
570 stored_nt->hash, challenge,
571 NULL)) {
572 /* The session key for this response is still very odd.
573 It not very secure, so use it only if we otherwise
574 allow LM authentication */
575
576 if (lanman_auth && stored_lanman) {
577 uint8_t first_8_lm_hash[16];
578 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
579 memset(first_8_lm_hash + 8, '\0', 8);
580 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
581 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
582 }
583 return NT_STATUS_OK;
584 }
585 DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
586 } else {
587 DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
588 }
589
590 /* Try and match error codes */
591 if (strchr_m(username, '@')) {
592 return NT_STATUS_NOT_FOUND;
593 }
594 return NT_STATUS_WRONG_PASSWORD;
595}
596
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