source/auth/ntlm_check.c

   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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24 #include "lib/crypto/crypto.h"
  25 #include "librpc/gen_ndr/netlogon.h"
  26 #include "libcli/auth/libcli_auth.h"
  27
  28 /****************************************************************************
  29  Core of smb password checking routine.
  30 ****************************************************************************/
  31
  32 static BOOL smb_pwd_check_ntlmv1(TALLOC_CTX *mem_ctx,
  33                                  const DATA_BLOB *nt_response,
  34                                  const uint8_t *part_passwd,
  35                                  const DATA_BLOB *sec_blob,
  36                                  DATA_BLOB *user_sess_key)
  37 {
  38         /* Finish the encryption of part_passwd. */
  39         uint8_t p24[24];
  40
  41         if (part_passwd == NULL) {
  42                 DEBUG(10,("No password set - DISALLOWING access\n"));
  43                 /* No password set - always false ! */
  44                 return False;
  45         }
  46
  47         if (sec_blob->length != 8) {
  48                 DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect challenge size (%lu)\n",
  49                           (unsigned long)sec_blob->length));
  50                 return False;
  51         }
  52
  53         if (nt_response->length != 24) {
  54                 DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect password length (%lu)\n",
  55                           (unsigned long)nt_response->length));
  56                 return False;
  57         }
  58
  59         SMBOWFencrypt(part_passwd, sec_blob->data, p24);
  60
  61 #if DEBUG_PASSWORD
  62         DEBUG(100,("Part password (P16) was |\n"));
  63         dump_data(100, part_passwd, 16);
  64         DEBUGADD(100,("Password from client was |\n"));
  65         dump_data(100, nt_response->data, nt_response->length);
  66         DEBUGADD(100,("Given challenge was |\n"));
  67         dump_data(100, sec_blob->data, sec_blob->length);
  68         DEBUGADD(100,("Value from encryption was |\n"));
  69         dump_data(100, p24, 24);
  70 #endif
  71         if (memcmp(p24, nt_response->data, 24) == 0) {
  72                 if (user_sess_key != NULL) {
  73                         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
  74                         SMBsesskeygen_ntv1(part_passwd, user_sess_key->data);
  75                 }
  76                 return True;
  77         }
  78         return False;
  79 }
  80
  81 /****************************************************************************
  82  Core of smb password checking routine. (NTLMv2, LMv2)
  83  Note:  The same code works with both NTLMv2 and LMv2.
  84 ****************************************************************************/
  85
  86 static BOOL smb_pwd_check_ntlmv2(TALLOC_CTX *mem_ctx,
  87                                  const DATA_BLOB *ntv2_response,
  88                                  const uint8_t *part_passwd,
  89                                  const DATA_BLOB *sec_blob,
  90                                  const char *user, const char *domain,
  91                                  BOOL upper_case_domain, /* should the domain be transformed into upper case? */
  92                                  DATA_BLOB *user_sess_key)
  93 {
  94         /* Finish the encryption of part_passwd. */
  95         uint8_t kr[16];
  96         uint8_t value_from_encryption[16];
  97         DATA_BLOB client_key_data;
  98
  99         if (part_passwd == NULL) {
 100                 DEBUG(10,("No password set - DISALLOWING access\n"));
 101                 /* No password set - always False */
 102                 return False;
 103         }
 104
 105         if (sec_blob->length != 8) {
 106                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
 107                           (unsigned long)sec_blob->length));
 108                 return False;
 109         }
 110
 111         if (ntv2_response->length < 24) {
 112                 /* We MUST have more than 16 bytes, or the stuff below will go
 113                    crazy.  No known implementation sends less than the 24 bytes
 114                    for LMv2, let alone NTLMv2. */
 115                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
 116                           (unsigned long)ntv2_response->length));
 117                 return False;
 118         }
 119
 120         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 121         /*
 122            todo:  should we be checking this for anything?  We can't for LMv2,
 123            but for NTLMv2 it is meant to contain the current time etc.
 124         */
 125
 126         if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
 127                 return False;
 128         }
 129
 130         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 131
 132 #if DEBUG_PASSWORD
 133         DEBUG(100,("Part password (P16) was |\n"));
 134         dump_data(100, part_passwd, 16);
 135         DEBUGADD(100,("Password from client was |\n"));
 136         dump_data(100, ntv2_response->data, ntv2_response->length);
 137         DEBUGADD(100,("Variable data from client was |\n"));
 138         dump_data(100, client_key_data.data, client_key_data.length);
 139         DEBUGADD(100,("Given challenge was |\n"));
 140         dump_data(100, sec_blob->data, sec_blob->length);
 141         DEBUGADD(100,("Value from encryption was |\n"));
 142         dump_data(100, value_from_encryption, 16);
 143 #endif
 144         data_blob_clear_free(&client_key_data);
 145         if (memcmp(value_from_encryption, ntv2_response->data, 16) == 0) {
 146                 if (user_sess_key != NULL) {
 147                         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 148                         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 149                 }
 150                 return True;
 151         }
 152         return False;
 153 }
 154
 155 /****************************************************************************
 156  Core of smb password checking routine. (NTLMv2, LMv2)
 157  Note:  The same code works with both NTLMv2 and LMv2.
 158 ****************************************************************************/
 159
 160 static BOOL smb_sess_key_ntlmv2(TALLOC_CTX *mem_ctx,
 161                                 const DATA_BLOB *ntv2_response,
 162                                 const uint8_t *part_passwd,
 163                                 const DATA_BLOB *sec_blob,
 164                                 const char *user, const char *domain,
 165                                 BOOL upper_case_domain, /* should the domain be transformed into upper case? */
 166                                 DATA_BLOB *user_sess_key)
 167 {
 168         /* Finish the encryption of part_passwd. */
 169         uint8_t kr[16];
 170         uint8_t value_from_encryption[16];
 171         DATA_BLOB client_key_data;
 172
 173         if (part_passwd == NULL) {
 174                 DEBUG(10,("No password set - DISALLOWING access\n"));
 175                 /* No password set - always False */
 176                 return False;
 177         }
 178
 179         if (sec_blob->length != 8) {
 180                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect challenge size (%lu)\n",
 181                           (unsigned long)sec_blob->length));
 182                 return False;
 183         }
 184
 185         if (ntv2_response->length < 24) {
 186                 /* We MUST have more than 16 bytes, or the stuff below will go
 187                    crazy.  No known implementation sends less than the 24 bytes
 188                    for LMv2, let alone NTLMv2. */
 189                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect password length (%lu)\n",
 190                           (unsigned long)ntv2_response->length));
 191                 return False;
 192         }
 193
 194         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 195
 196         if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
 197                 return False;
 198         }
 199
 200         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 201         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 202         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 203         return True;
 204 }
 205
 206 /**
 207  * Compare password hashes against those from the SAM
 208  *
 209  * @param mem_ctx talloc context
 210  * @param client_lanman LANMAN password hash, as supplied by the client
 211  * @param client_nt NT (MD4) password hash, as supplied by the client
 212  * @param username internal Samba username, for log messages
 213  * @param client_username username the client used
 214  * @param client_domain domain name the client used (may be mapped)
 215  * @param stored_lanman LANMAN password hash, as stored on the SAM
 216  * @param stored_nt NT (MD4) password hash, as stored on the SAM
 217  * @param user_sess_key User session key
 218  * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
 219  */
 220
 221 NTSTATUS hash_password_check(TALLOC_CTX *mem_ctx,
 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 (!lp_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
 283 NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
 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         static const uint8_t zeros[8];
 297         DATA_BLOB tmp_sess_key;
 298
 299         if (stored_nt == NULL) {
 300                 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
 301                          username));
 302         }
 303
 304         *lm_sess_key = data_blob(NULL, 0);
 305         *user_sess_key = data_blob(NULL, 0);
 306
 307         /* Check for cleartext netlogon. Used by Exchange 5.5. */
 308         if ((logon_parameters & MSV1_0_CLEARTEXT_PASSWORD_ALLOWED)
 309             && challenge->length == sizeof(zeros)
 310             && (memcmp(challenge->data, zeros, challenge->length) == 0 )) {
 311                 struct samr_Password client_nt;
 312                 struct samr_Password client_lm;
 313                 char *unix_pw = NULL;
 314                 BOOL lm_ok;
 315
 316                 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
 317                          username));
 318                 mdfour(client_nt.hash, nt_response->data, nt_response->length);
 319
 320                 if (lm_response->length &&
 321                     (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
 322                                           lm_response->data, lm_response->length,
 323                                            (void **)&unix_pw) != -1)) {
 324                         if (E_deshash(unix_pw, client_lm.hash)) {
 325                                 lm_ok = True;
 326                         } else {
 327                                 lm_ok = False;
 328                         }
 329                 } else {
 330                         lm_ok = False;
 331                 }
 332                 return hash_password_check(mem_ctx,
 333                                            lm_ok ? &client_lm : NULL,
 334                                            nt_response->length ? &client_nt : NULL,
 335                                            username,
 336                                            stored_lanman, stored_nt);
 337         }
 338
 339         if (nt_response->length != 0 && nt_response->length < 24) {
 340                 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
 341                          (unsigned long)nt_response->length, username));
 342         }
 343
 344         if (nt_response->length > 24 && stored_nt) {
 345                 /* We have the NT MD4 hash challenge available - see if we can
 346                    use it
 347                 */
 348                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n", client_domain));
 349                 if (smb_pwd_check_ntlmv2(mem_ctx,
 350                                          nt_response,
 351                                          stored_nt->hash, challenge,
 352                                          client_username,
 353                                          client_domain,
 354                                          False,
 355                                          user_sess_key)) {
 356                         *lm_sess_key = *user_sess_key;
 357                         if (user_sess_key->length) {
 358                                 lm_sess_key->length = 8;
 359                         }
 360                         return NT_STATUS_OK;
 361                 }
 362
 363                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n", client_domain));
 364                 if (smb_pwd_check_ntlmv2(mem_ctx,
 365                                          nt_response,
 366                                          stored_nt->hash, challenge,
 367                                          client_username,
 368                                          client_domain,
 369                                          True,
 370                                          user_sess_key)) {
 371                         *lm_sess_key = *user_sess_key;
 372                         if (user_sess_key->length) {
 373                                 lm_sess_key->length = 8;
 374                         }
 375                         return NT_STATUS_OK;
 376                 }
 377
 378                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
 379                 if (smb_pwd_check_ntlmv2(mem_ctx,
 380                                          nt_response,
 381                                          stored_nt->hash, challenge,
 382                                          client_username,
 383                                          "",
 384                                          False,
 385                                          user_sess_key)) {
 386                         *lm_sess_key = *user_sess_key;
 387                         if (user_sess_key->length) {
 388                                 lm_sess_key->length = 8;
 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 (lp_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 (lp_lanman_auth() && stored_lanman) {
 408                                         *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
 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 (!lp_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 (lp_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                 *lm_sess_key = *user_sess_key;
 498                 if (user_sess_key->length) {
 499                         lm_sess_key->length = 8;
 500                 }
 501                 return NT_STATUS_OK;
 502         }
 503
 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;
 527                 }
 528                 *lm_sess_key = *user_sess_key;
 529                 if (user_sess_key->length) {
 530                         lm_sess_key->length = 8;
 531                 }
 532                 return NT_STATUS_OK;
 533         }
 534
 535         DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
 536         if (smb_pwd_check_ntlmv2(mem_ctx,
 537                                  lm_response,
 538                                  stored_nt->hash, challenge,
 539                                  client_username,
 540                                  "",
 541                                  False,
 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                                             False,
 554                                             user_sess_key);
 555                 } else {
 556                         /* Otherwise, use the LMv2 session key */
 557                         *user_sess_key = tmp_sess_key;
 558                 }
 559                 *lm_sess_key = *user_sess_key;
 560                 if (user_sess_key->length) {
 561                         lm_sess_key->length = 8;
 562                 }
 563                 return NT_STATUS_OK;
 564         }
 565
 566         /* Apparently NT accepts NT responses in the LM field
 567            - I think this is related to Win9X pass-though authentication
 568         */
 569         DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
 570         if (lp_ntlm_auth()) {
 571                 if (smb_pwd_check_ntlmv1(mem_ctx,
 572                                          lm_response,
 573                                          stored_nt->hash, challenge,
 574                                          NULL)) {
 575                         /* The session key for this response is still very odd.
 576                            It not very secure, so use it only if we otherwise
 577                            allow LM authentication */
 578
 579                         if (lp_lanman_auth() && stored_lanman) {
 580                                 uint8_t first_8_lm_hash[16];
 581                                 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
 582                                 memset(first_8_lm_hash + 8, '\0', 8);
 583                                 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
 584                                 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
 585                         }
 586                         return NT_STATUS_OK;
 587                 }
 588                 DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
 589         } else {
 590                 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         }
 592
 593         /* Try and match error codes */
 594         if (strchr_m(username, '@')) {
 595                 return NT_STATUS_NOT_FOUND;
 596         }
 597         return NT_STATUS_WRONG_PASSWORD;
 598 }
 599