Make reinit_after_fork_pipe_handler code with reads being interrupted by a signal.
[Samba/vl.git] / libcli / auth / ntlm_check.c
blob9520d32a1e8afa5930aac90c512d52dc628245d4
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
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.
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.
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/>.
22 #include "includes.h"
23 #include "../lib/crypto/crypto.h"
24 #include "librpc/gen_ndr/netlogon.h"
25 #include "libcli/auth/libcli_auth.h"
27 /****************************************************************************
28 Core of smb password checking routine.
29 ****************************************************************************/
31 static 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)
37 /* Finish the encryption of part_passwd. */
38 uint8_t p24[24];
40 if (part_passwd == NULL) {
41 DEBUG(10,("No password set - DISALLOWING access\n"));
42 /* No password set - always false ! */
43 return false;
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;
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;
58 SMBOWFencrypt(part_passwd, sec_blob->data, p24);
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);
75 return true;
77 return false;
80 /****************************************************************************
81 Core of smb password checking routine. (NTLMv2, LMv2)
82 Note: The same code works with both NTLMv2 and LMv2.
83 ****************************************************************************/
85 static 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)
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;
98 if (part_passwd == NULL) {
99 DEBUG(10,("No password set - DISALLOWING access\n"));
100 /* No password set - always false */
101 return false;
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;
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;
119 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
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.
125 if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
126 return false;
129 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
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);
149 return true;
151 return false;
154 /****************************************************************************
155 Core of smb password checking routine. (NTLMv2, LMv2)
156 Note: The same code works with both NTLMv2 and LMv2.
157 ****************************************************************************/
159 static 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)
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;
172 if (part_passwd == NULL) {
173 DEBUG(10,("No password set - DISALLOWING access\n"));
174 /* No password set - always false */
175 return false;
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;
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;
193 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
195 if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
196 return false;
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;
206 * Compare password hashes against those from the SAM
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)
220 NTSTATUS 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)
228 if (stored_nt == NULL) {
229 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
230 username));
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;
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;
248 if (strchr_m(username, '@')) {
249 return NT_STATUS_NOT_FOUND;
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;
260 if (strchr_m(username, '@')) {
261 return NT_STATUS_NOT_FOUND;
263 return NT_STATUS_WRONG_PASSWORD;
267 * Check a challenge-response password against the value of the NT or
268 * LM password hash.
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)
283 NTSTATUS 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)
298 const static uint8_t zeros[8];
299 DATA_BLOB tmp_sess_key;
301 if (stored_nt == NULL) {
302 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
303 username));
306 *lm_sess_key = data_blob(NULL, 0);
307 *user_sess_key = data_blob(NULL, 0);
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 size_t converted_size = 0;
319 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
320 username));
321 mdfour(client_nt.hash, nt_response->data, nt_response->length);
323 if (lm_response->length &&
324 (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
325 lm_response->data, lm_response->length,
326 (void *)&unix_pw, &converted_size))) {
327 if (E_deshash(unix_pw, client_lm.hash)) {
328 lm_ok = true;
329 } else {
330 lm_ok = false;
332 } else {
333 lm_ok = false;
335 return hash_password_check(mem_ctx,
336 lanman_auth,
337 lm_ok ? &client_lm : NULL,
338 nt_response->length ? &client_nt : NULL,
339 username,
340 stored_lanman, stored_nt);
343 if (nt_response->length != 0 && nt_response->length < 24) {
344 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
345 (unsigned long)nt_response->length, username));
348 if (nt_response->length > 24 && stored_nt) {
349 /* We have the NT MD4 hash challenge available - see if we can
350 use it
352 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n", client_domain));
353 if (smb_pwd_check_ntlmv2(mem_ctx,
354 nt_response,
355 stored_nt->hash, challenge,
356 client_username,
357 client_domain,
358 false,
359 user_sess_key)) {
360 if (user_sess_key->length) {
361 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
363 return NT_STATUS_OK;
366 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n", client_domain));
367 if (smb_pwd_check_ntlmv2(mem_ctx,
368 nt_response,
369 stored_nt->hash, challenge,
370 client_username,
371 client_domain,
372 true,
373 user_sess_key)) {
374 if (user_sess_key->length) {
375 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
377 return NT_STATUS_OK;
380 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
381 if (smb_pwd_check_ntlmv2(mem_ctx,
382 nt_response,
383 stored_nt->hash, challenge,
384 client_username,
386 false,
387 user_sess_key)) {
388 if (user_sess_key->length) {
389 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
391 return NT_STATUS_OK;
392 } else {
393 DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
395 } else if (nt_response->length == 24 && stored_nt) {
396 if (ntlm_auth) {
397 /* We have the NT MD4 hash challenge available - see if we can
398 use it (ie. does it exist in the smbpasswd file).
400 DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
401 if (smb_pwd_check_ntlmv1(mem_ctx,
402 nt_response,
403 stored_nt->hash, challenge,
404 user_sess_key)) {
405 /* The LM session key for this response is not very secure,
406 so use it only if we otherwise allow LM authentication */
408 if (lanman_auth && stored_lanman) {
409 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
411 return NT_STATUS_OK;
412 } else {
413 DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
414 username));
415 return NT_STATUS_WRONG_PASSWORD;
417 } else {
418 DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
419 username));
420 /* no return, because we might pick up LMv2 in the LM field */
424 if (lm_response->length == 0) {
425 DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
426 username));
427 return NT_STATUS_WRONG_PASSWORD;
430 if (lm_response->length < 24) {
431 DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
432 (unsigned long)nt_response->length, username));
433 return NT_STATUS_WRONG_PASSWORD;
436 if (!lanman_auth) {
437 DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
438 username));
439 } else if (!stored_lanman) {
440 DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
441 username));
442 } else if (strchr_m(username, '@')) {
443 DEBUG(3,("ntlm_password_check: NO LanMan password allowed for username@realm logins (user: %s)\n",
444 username));
445 } else {
446 DEBUG(4,("ntlm_password_check: Checking LM password\n"));
447 if (smb_pwd_check_ntlmv1(mem_ctx,
448 lm_response,
449 stored_lanman->hash, challenge,
450 NULL)) {
451 /* The session key for this response is still very odd.
452 It not very secure, so use it only if we otherwise
453 allow LM authentication */
455 if (lanman_auth && stored_lanman) {
456 uint8_t first_8_lm_hash[16];
457 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
458 memset(first_8_lm_hash + 8, '\0', 8);
459 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
460 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
462 return NT_STATUS_OK;
466 if (!stored_nt) {
467 DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
468 return NT_STATUS_WRONG_PASSWORD;
471 /* This is for 'LMv2' authentication. almost NTLMv2 but limited to 24 bytes.
472 - related to Win9X, legacy NAS pass-though authentication
474 DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n", client_domain));
475 if (smb_pwd_check_ntlmv2(mem_ctx,
476 lm_response,
477 stored_nt->hash, challenge,
478 client_username,
479 client_domain,
480 false,
481 &tmp_sess_key)) {
482 if (nt_response->length > 24) {
483 /* If NTLMv2 authentication has preceeded us
484 * (even if it failed), then use the session
485 * key from that. See the RPC-SAMLOGON
486 * torture test */
487 smb_sess_key_ntlmv2(mem_ctx,
488 nt_response,
489 stored_nt->hash, challenge,
490 client_username,
491 client_domain,
492 false,
493 user_sess_key);
494 } else {
495 /* Otherwise, use the LMv2 session key */
496 *user_sess_key = tmp_sess_key;
498 if (user_sess_key->length) {
499 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
501 return NT_STATUS_OK;
504 DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n", client_domain));
505 if (smb_pwd_check_ntlmv2(mem_ctx,
506 lm_response,
507 stored_nt->hash, challenge,
508 client_username,
509 client_domain,
510 true,
511 &tmp_sess_key)) {
512 if (nt_response->length > 24) {
513 /* If NTLMv2 authentication has preceeded us
514 * (even if it failed), then use the session
515 * key from that. See the RPC-SAMLOGON
516 * torture test */
517 smb_sess_key_ntlmv2(mem_ctx,
518 nt_response,
519 stored_nt->hash, challenge,
520 client_username,
521 client_domain,
522 true,
523 user_sess_key);
524 } else {
525 /* Otherwise, use the LMv2 session key */
526 *user_sess_key = tmp_sess_key;
528 if (user_sess_key->length) {
529 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
531 return NT_STATUS_OK;
534 DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
535 if (smb_pwd_check_ntlmv2(mem_ctx,
536 lm_response,
537 stored_nt->hash, challenge,
538 client_username,
540 false,
541 &tmp_sess_key)) {
542 if (nt_response->length > 24) {
543 /* If NTLMv2 authentication has preceeded us
544 * (even if it failed), then use the session
545 * key from that. See the RPC-SAMLOGON
546 * torture test */
547 smb_sess_key_ntlmv2(mem_ctx,
548 nt_response,
549 stored_nt->hash, challenge,
550 client_username,
552 false,
553 user_sess_key);
554 } else {
555 /* Otherwise, use the LMv2 session key */
556 *user_sess_key = tmp_sess_key;
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));
561 return NT_STATUS_OK;
564 /* Apparently NT accepts NT responses in the LM field
565 - I think this is related to Win9X pass-though authentication
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 */
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);
584 return NT_STATUS_OK;
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));
591 /* Try and match error codes */
592 if (strchr_m(username, '@')) {
593 return NT_STATUS_NOT_FOUND;
595 return NT_STATUS_WRONG_PASSWORD;