libcli/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 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/md4.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
  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)
  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
  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)
  91 {
  92         /* Finish the encryption of part_passwd. */
  93         uint8_t kr[16];
  94         uint8_t value_from_encryption[16];
  95         DATA_BLOB client_key_data;
  96
  97         if (part_passwd == NULL) {
  98                 DEBUG(10,("No password set - DISALLOWING access\n"));
  99                 /* No password set - always false */
 100                 return false;
 101         }
 102
 103         if (sec_blob->length != 8) {
 104                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
 105                           (unsigned long)sec_blob->length));
 106                 return false;
 107         }
 108
 109         if (ntv2_response->length < 24) {
 110                 /* We MUST have more than 16 bytes, or the stuff below will go
 111                    crazy.  No known implementation sends less than the 24 bytes
 112                    for LMv2, let alone NTLMv2. */
 113                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
 114                           (unsigned long)ntv2_response->length));
 115                 return false;
 116         }
 117
 118         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 119         /*
 120            todo:  should we be checking this for anything?  We can't for LMv2,
 121            but for NTLMv2 it is meant to contain the current time etc.
 122         */
 123
 124         if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
 125                 return false;
 126         }
 127
 128         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 129
 130 #if DEBUG_PASSWORD
 131         DEBUG(100,("Part password (P16) was |\n"));
 132         dump_data(100, part_passwd, 16);
 133         DEBUGADD(100,("Password from client was |\n"));
 134         dump_data(100, ntv2_response->data, ntv2_response->length);
 135         DEBUGADD(100,("Variable data from client was |\n"));
 136         dump_data(100, client_key_data.data, client_key_data.length);
 137         DEBUGADD(100,("Given challenge was |\n"));
 138         dump_data(100, sec_blob->data, sec_blob->length);
 139         DEBUGADD(100,("Value from encryption was |\n"));
 140         dump_data(100, value_from_encryption, 16);
 141 #endif
 142         data_blob_clear_free(&client_key_data);
 143         if (memcmp(value_from_encryption, ntv2_response->data, 16) == 0) {
 144                 if (user_sess_key != NULL) {
 145                         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 146                         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 147                 }
 148                 return true;
 149         }
 150         return false;
 151 }
 152
 153 /****************************************************************************
 154  Core of smb password checking routine. (NTLMv2, LMv2)
 155  Note:  The same code works with both NTLMv2 and LMv2.
 156 ****************************************************************************/
 157
 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)
 164 {
 165         /* Finish the encryption of part_passwd. */
 166         uint8_t kr[16];
 167         uint8_t value_from_encryption[16];
 168         DATA_BLOB client_key_data;
 169
 170         if (part_passwd == NULL) {
 171                 DEBUG(10,("No password set - DISALLOWING access\n"));
 172                 /* No password set - always false */
 173                 return false;
 174         }
 175
 176         if (sec_blob->length != 8) {
 177                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect challenge size (%lu)\n",
 178                           (unsigned long)sec_blob->length));
 179                 return false;
 180         }
 181
 182         if (ntv2_response->length < 24) {
 183                 /* We MUST have more than 16 bytes, or the stuff below will go
 184                    crazy.  No known implementation sends less than the 24 bytes
 185                    for LMv2, let alone NTLMv2. */
 186                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect password length (%lu)\n",
 187                           (unsigned long)ntv2_response->length));
 188                 return false;
 189         }
 190
 191         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 192
 193         if (!ntv2_owf_gen(part_passwd, user, domain, kr)) {
 194                 return false;
 195         }
 196
 197         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 198         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 199         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 200         return true;
 201 }
 202
 203 /**
 204  * Compare password hashes against those from the SAM
 205  *
 206  * @param mem_ctx talloc context
 207  * @param client_lanman LANMAN password hash, as supplied by the client
 208  * @param client_nt NT (MD4) password hash, as supplied by the client
 209  * @param username internal Samba username, for log messages
 210  * @param client_username username the client used
 211  * @param client_domain domain name the client used (may be mapped)
 212  * @param stored_lanman LANMAN password hash, as stored on the SAM
 213  * @param stored_nt NT (MD4) password hash, as stored on the SAM
 214  * @param user_sess_key User session key
 215  * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
 216  */
 217
 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)
 225 {
 226         if (stored_nt == NULL) {
 227                 DEBUG(3,("hash_password_check: NO NT password stored for user %s.\n",
 228                          username));
 229         }
 230
 231         if (client_nt && stored_nt) {
 232                 if (memcmp(client_nt->hash, stored_nt->hash, sizeof(stored_nt->hash)) == 0) {
 233                         return NT_STATUS_OK;
 234                 } else {
 235                         DEBUG(3,("hash_password_check: Interactive logon: NT password check failed for user %s\n",
 236                                  username));
 237                         return NT_STATUS_WRONG_PASSWORD;
 238                 }
 239
 240         } else if (client_lanman && stored_lanman) {
 241                 if (!lanman_auth) {
 242                         DEBUG(3,("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;
 245                 }
 246                 if (strchr_m(username, '@')) {
 247                         return NT_STATUS_NOT_FOUND;
 248                 }
 249
 250                 if (memcmp(client_lanman->hash, stored_lanman->hash, sizeof(stored_lanman->hash)) == 0) {
 251                         return NT_STATUS_OK;
 252                 } else {
 253                         DEBUG(3,("hash_password_check: Interactive logon: LANMAN password check failed for user %s\n",
 254                                  username));
 255                         return NT_STATUS_WRONG_PASSWORD;
 256                 }
 257         }
 258         if (strchr_m(username, '@')) {
 259                 return NT_STATUS_NOT_FOUND;
 260         }
 261         return NT_STATUS_WRONG_PASSWORD;
 262 }
 263
 264 /**
 265  * Check a challenge-response password against the value of the NT or
 266  * LM password hash.
 267  *
 268  * @param mem_ctx talloc context
 269  * @param challenge 8-byte challenge.  If all zero, forces plaintext comparison
 270  * @param nt_response 'unicode' NT response to the challenge, or unicode password
 271  * @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
 272  * @param username internal Samba username, for log messages
 273  * @param client_username username the client used
 274  * @param client_domain domain name the client used (may be mapped)
 275  * @param stored_lanman LANMAN ASCII password from our passdb or similar
 276  * @param stored_nt MD4 unicode password from our passdb or similar
 277  * @param user_sess_key User session key
 278  * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
 279  */
 280
 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)
 295 {
 296         DATA_BLOB tmp_sess_key;
 297         const char *upper_client_domain = NULL;
 298
 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;
 303         }
 304
 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;
 309                 }
 310         }
 311
 312         if (stored_nt == NULL) {
 313                 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
 314                          username));
 315         }
 316
 317         *lm_sess_key = data_blob(NULL, 0);
 318         *user_sess_key = data_blob(NULL, 0);
 319
 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;
 329
 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);
 333
 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;
 342                         }
 343                 } else {
 344                         lm_ok = false;
 345                 }
 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);
 352         }
 353
 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));
 357         }
 358
 359         if (nt_response->length > 24 && stored_nt) {
 360                 /* We have the NT MD4 hash challenge available - see if we can
 361                    use it
 362                 */
 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));
 373                         }
 374                         return NT_STATUS_OK;
 375                 }
 376
 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));
 387                         }
 388                         return NT_STATUS_OK;
 389                 }
 390
 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,
 396                                          "",
 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));
 400                         }
 401                         return NT_STATUS_OK;
 402                 } else {
 403                         DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
 404                 }
 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).
 410                         */
 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 */
 418
 419                                 if (lanman_auth && stored_lanman) {
 420                                         *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
 421                                 }
 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;
 427                         }
 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 */
 432                 }
 433         }
 434
 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;
 439         }
 440
 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;
 445         }
 446
 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 */
 465
 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);
 472                         }
 473                         return NT_STATUS_OK;
 474                 }
 475         }
 476
 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;
 480         }
 481
 482         /* This is for 'LMv2' authentication.  almost NTLMv2 but limited to 24 bytes.
 483            - related to Win9X, legacy NAS pass-though authentication
 484         */
 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;
 507                 }
 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));
 510                 }
 511                 return NT_STATUS_OK;
 512         }
 513
 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;
 536                 }
 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));
 539                 }
 540                 return NT_STATUS_OK;
 541         }
 542
 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,
 548                                  "",
 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,
 559                                             "",
 560                                             user_sess_key);
 561                 } else {
 562                         /* Otherwise, use the LMv2 session key */
 563                         *user_sess_key = tmp_sess_key;
 564                 }
 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));
 567                 }
 568                 return NT_STATUS_OK;
 569         }
 570
 571         /* Apparently NT accepts NT responses in the LM field
 572            - I think this is related to Win9X pass-though authentication
 573         */
 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 */
 583
 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);
 590                         }
 591                         return NT_STATUS_OK;
 592                 }
 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));
 596         }
 597
 598         /* Try and match error codes */
 599         if (strchr_m(username, '@')) {
 600                 return NT_STATUS_NOT_FOUND;
 601         }
 602         return NT_STATUS_WRONG_PASSWORD;
 603 }
 604