libcli:auth: Only use the required md4 header
[Samba.git] / libcli / auth / ntlm_check.c
blob3844abde5282df8db34c0bd498534e38469ed515
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/md4.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 DATA_BLOB *user_sess_key)
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;
97 if (part_passwd == NULL) {
98 DEBUG(10,("No password set - DISALLOWING access\n"));
99 /* No password set - always false */
100 return false;
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;
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;
118 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
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.
124 if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
125 return false;
128 SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
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);
148 return true;
150 return false;
153 /****************************************************************************
154 Core of smb password checking routine. (NTLMv2, LMv2)
155 Note: The same code works with both NTLMv2 and LMv2.
156 ****************************************************************************/
158 static 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)
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;
170 if (part_passwd == NULL) {
171 DEBUG(10,("No password set - DISALLOWING access\n"));
172 /* No password set - always false */
173 return false;
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;
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;
191 client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
193 if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
194 return false;
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;
204 * Compare password hashes against those from the SAM
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)
218 NTSTATUS 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)
226 if (stored_nt == NULL) {
227 DEBUG(3,("hash_password_check: NO NT password stored for user %s.\n",
228 username));
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,("hash_password_check: Interactive logon: NT password check failed for user %s\n",
236 username));
237 return NT_STATUS_WRONG_PASSWORD;
240 } else if (client_lanman && stored_lanman) {
241 if (!lanman_auth) {
242 DEBUG(3,("hash_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;
246 if (strchr_m(username, '@')) {
247 return NT_STATUS_NOT_FOUND;
250 if (memcmp(client_lanman->hash, stored_lanman->hash, sizeof(stored_lanman->hash)) == 0) {
251 return NT_STATUS_OK;
252 } else {
253 DEBUG(3,("hash_password_check: Interactive logon: LANMAN password check failed for user %s\n",
254 username));
255 return NT_STATUS_WRONG_PASSWORD;
258 if (strchr_m(username, '@')) {
259 return NT_STATUS_NOT_FOUND;
261 return NT_STATUS_WRONG_PASSWORD;
265 * Check a challenge-response password against the value of the NT or
266 * LM password hash.
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)
281 NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
282 bool lanman_auth,
283 enum ntlm_auth_level 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)
296 DATA_BLOB tmp_sess_key;
297 const char *upper_client_domain = NULL;
299 if (ntlm_auth == NTLM_AUTH_DISABLED) {
300 DBG_WARNING("ntlm_password_check: NTLM authentication not "
301 "permitted by configuration.\n");
302 return NT_STATUS_NTLM_BLOCKED;
305 if (client_domain != NULL) {
306 upper_client_domain = talloc_strdup_upper(mem_ctx, client_domain);
307 if (upper_client_domain == NULL) {
308 return NT_STATUS_NO_MEMORY;
312 if (stored_nt == NULL) {
313 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
314 username));
317 *lm_sess_key = data_blob(NULL, 0);
318 *user_sess_key = data_blob(NULL, 0);
320 /* Check for cleartext netlogon. Used by Exchange 5.5. */
321 if ((logon_parameters & MSV1_0_CLEARTEXT_PASSWORD_ALLOWED)
322 && challenge->length == 8
323 && (all_zero(challenge->data, challenge->length))) {
324 struct samr_Password client_nt;
325 struct samr_Password client_lm;
326 char *unix_pw = NULL;
327 bool lm_ok;
328 size_t converted_size = 0;
330 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
331 username));
332 mdfour(client_nt.hash, nt_response->data, nt_response->length);
334 if (lm_response->length &&
335 (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
336 lm_response->data, lm_response->length,
337 (void *)&unix_pw, &converted_size))) {
338 if (E_deshash(unix_pw, client_lm.hash)) {
339 lm_ok = true;
340 } else {
341 lm_ok = false;
343 } else {
344 lm_ok = false;
346 return hash_password_check(mem_ctx,
347 lanman_auth,
348 lm_ok ? &client_lm : NULL,
349 nt_response->length ? &client_nt : NULL,
350 username,
351 stored_lanman, stored_nt);
354 if (nt_response->length != 0 && nt_response->length < 24) {
355 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
356 (unsigned long)nt_response->length, username));
359 if (nt_response->length > 24 && stored_nt) {
360 /* We have the NT MD4 hash challenge available - see if we can
361 use it
363 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n",
364 client_domain ? client_domain : "<NULL>"));
365 if (smb_pwd_check_ntlmv2(mem_ctx,
366 nt_response,
367 stored_nt->hash, challenge,
368 client_username,
369 client_domain,
370 user_sess_key)) {
371 if (user_sess_key->length) {
372 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
374 return NT_STATUS_OK;
377 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n",
378 upper_client_domain ? upper_client_domain : "<NULL>"));
379 if (smb_pwd_check_ntlmv2(mem_ctx,
380 nt_response,
381 stored_nt->hash, challenge,
382 client_username,
383 upper_client_domain,
384 user_sess_key)) {
385 if (user_sess_key->length) {
386 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
388 return NT_STATUS_OK;
391 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
392 if (smb_pwd_check_ntlmv2(mem_ctx,
393 nt_response,
394 stored_nt->hash, challenge,
395 client_username,
397 user_sess_key)) {
398 if (user_sess_key->length) {
399 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
401 return NT_STATUS_OK;
402 } else {
403 DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
405 } else if (nt_response->length == 24 && stored_nt) {
406 if (ntlm_auth == NTLM_AUTH_ON
407 || (ntlm_auth == NTLM_AUTH_MSCHAPv2_NTLMV2_ONLY && (logon_parameters & MSV1_0_ALLOW_MSVCHAPV2))) {
408 /* We have the NT MD4 hash challenge available - see if we can
409 use it (ie. does it exist in the smbpasswd file).
411 DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
412 if (smb_pwd_check_ntlmv1(mem_ctx,
413 nt_response,
414 stored_nt->hash, challenge,
415 user_sess_key)) {
416 /* The LM session key for this response is not very secure,
417 so use it only if we otherwise allow LM authentication */
419 if (lanman_auth && stored_lanman) {
420 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
422 return NT_STATUS_OK;
423 } else {
424 DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
425 username));
426 return NT_STATUS_WRONG_PASSWORD;
428 } else {
429 DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
430 username));
431 /* no return, because we might pick up LMv2 in the LM field */
435 if (lm_response->length == 0) {
436 DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
437 username));
438 return NT_STATUS_WRONG_PASSWORD;
441 if (lm_response->length < 24) {
442 DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
443 (unsigned long)nt_response->length, username));
444 return NT_STATUS_WRONG_PASSWORD;
447 if (!lanman_auth) {
448 DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
449 username));
450 } else if (!stored_lanman) {
451 DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
452 username));
453 } else if (strchr_m(username, '@')) {
454 DEBUG(3,("ntlm_password_check: NO LanMan password allowed for username@realm logins (user: %s)\n",
455 username));
456 } else {
457 DEBUG(4,("ntlm_password_check: Checking LM password\n"));
458 if (smb_pwd_check_ntlmv1(mem_ctx,
459 lm_response,
460 stored_lanman->hash, challenge,
461 NULL)) {
462 /* The session key for this response is still very odd.
463 It not very secure, so use it only if we otherwise
464 allow LM authentication */
466 if (lanman_auth && stored_lanman) {
467 uint8_t first_8_lm_hash[16];
468 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
469 memset(first_8_lm_hash + 8, '\0', 8);
470 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
471 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
473 return NT_STATUS_OK;
477 if (!stored_nt) {
478 DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
479 return NT_STATUS_WRONG_PASSWORD;
482 /* This is for 'LMv2' authentication. almost NTLMv2 but limited to 24 bytes.
483 - related to Win9X, legacy NAS pass-though authentication
485 DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n",
486 client_domain ? client_domain : "<NULL>"));
487 if (smb_pwd_check_ntlmv2(mem_ctx,
488 lm_response,
489 stored_nt->hash, challenge,
490 client_username,
491 client_domain,
492 &tmp_sess_key)) {
493 if (nt_response->length > 24) {
494 /* If NTLMv2 authentication has preceded us
495 * (even if it failed), then use the session
496 * key from that. See the RPC-SAMLOGON
497 * torture test */
498 smb_sess_key_ntlmv2(mem_ctx,
499 nt_response,
500 stored_nt->hash, challenge,
501 client_username,
502 client_domain,
503 user_sess_key);
504 } else {
505 /* Otherwise, use the LMv2 session key */
506 *user_sess_key = tmp_sess_key;
508 if (user_sess_key->length) {
509 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
511 return NT_STATUS_OK;
514 DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n",
515 upper_client_domain ? upper_client_domain : "<NULL>"));
516 if (smb_pwd_check_ntlmv2(mem_ctx,
517 lm_response,
518 stored_nt->hash, challenge,
519 client_username,
520 upper_client_domain,
521 &tmp_sess_key)) {
522 if (nt_response->length > 24) {
523 /* If NTLMv2 authentication has preceded us
524 * (even if it failed), then use the session
525 * key from that. See the RPC-SAMLOGON
526 * torture test */
527 smb_sess_key_ntlmv2(mem_ctx,
528 nt_response,
529 stored_nt->hash, challenge,
530 client_username,
531 upper_client_domain,
532 user_sess_key);
533 } else {
534 /* Otherwise, use the LMv2 session key */
535 *user_sess_key = tmp_sess_key;
537 if (user_sess_key->length) {
538 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
540 return NT_STATUS_OK;
543 DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
544 if (smb_pwd_check_ntlmv2(mem_ctx,
545 lm_response,
546 stored_nt->hash, challenge,
547 client_username,
549 &tmp_sess_key)) {
550 if (nt_response->length > 24) {
551 /* If NTLMv2 authentication has preceded us
552 * (even if it failed), then use the session
553 * key from that. See the RPC-SAMLOGON
554 * torture test */
555 smb_sess_key_ntlmv2(mem_ctx,
556 nt_response,
557 stored_nt->hash, challenge,
558 client_username,
560 user_sess_key);
561 } else {
562 /* Otherwise, use the LMv2 session key */
563 *user_sess_key = tmp_sess_key;
565 if (user_sess_key->length) {
566 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
568 return NT_STATUS_OK;
571 /* Apparently NT accepts NT responses in the LM field
572 - I think this is related to Win9X pass-though authentication
574 DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
575 if (ntlm_auth == NTLM_AUTH_ON) {
576 if (smb_pwd_check_ntlmv1(mem_ctx,
577 lm_response,
578 stored_nt->hash, challenge,
579 NULL)) {
580 /* The session key for this response is still very odd.
581 It not very secure, so use it only if we otherwise
582 allow LM authentication */
584 if (lanman_auth && stored_lanman) {
585 uint8_t first_8_lm_hash[16];
586 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
587 memset(first_8_lm_hash + 8, '\0', 8);
588 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
589 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
591 return NT_STATUS_OK;
593 DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
594 } else {
595 DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
598 /* Try and match error codes */
599 if (strchr_m(username, '@')) {
600 return NT_STATUS_NOT_FOUND;
602 return NT_STATUS_WRONG_PASSWORD;