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/crypto.h"
  24 #include "librpc/gen_ndr/netlogon.h"
  25 #include "libcli/auth/libcli_auth.h"
  26
  27 /****************************************************************************
  28  Core of smb password checking routine.
  29 ****************************************************************************/
  30
  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                                  bool upper_case_domain, /* should the domain be transformed into upper case? */
  91                                  DATA_BLOB *user_sess_key)
  92 {
  93         /* Finish the encryption of part_passwd. */
  94         uint8_t kr[16];
  95         uint8_t value_from_encryption[16];
  96         DATA_BLOB client_key_data;
  97
  98         if (part_passwd == NULL) {
  99                 DEBUG(10,("No password set - DISALLOWING access\n"));
 100                 /* No password set - always false */
 101                 return false;
 102         }
 103
 104         if (sec_blob->length != 8) {
 105                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n",
 106                           (unsigned long)sec_blob->length));
 107                 return false;
 108         }
 109
 110         if (ntv2_response->length < 24) {
 111                 /* We MUST have more than 16 bytes, or the stuff below will go
 112                    crazy.  No known implementation sends less than the 24 bytes
 113                    for LMv2, let alone NTLMv2. */
 114                 DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n",
 115                           (unsigned long)ntv2_response->length));
 116                 return false;
 117         }
 118
 119         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 120         /*
 121            todo:  should we be checking this for anything?  We can't for LMv2,
 122            but for NTLMv2 it is meant to contain the current time etc.
 123         */
 124
 125         if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
 126                 return false;
 127         }
 128
 129         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 130
 131 #if DEBUG_PASSWORD
 132         DEBUG(100,("Part password (P16) was |\n"));
 133         dump_data(100, part_passwd, 16);
 134         DEBUGADD(100,("Password from client was |\n"));
 135         dump_data(100, ntv2_response->data, ntv2_response->length);
 136         DEBUGADD(100,("Variable data from client was |\n"));
 137         dump_data(100, client_key_data.data, client_key_data.length);
 138         DEBUGADD(100,("Given challenge was |\n"));
 139         dump_data(100, sec_blob->data, sec_blob->length);
 140         DEBUGADD(100,("Value from encryption was |\n"));
 141         dump_data(100, value_from_encryption, 16);
 142 #endif
 143         data_blob_clear_free(&client_key_data);
 144         if (memcmp(value_from_encryption, ntv2_response->data, 16) == 0) {
 145                 if (user_sess_key != NULL) {
 146                         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 147                         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 148                 }
 149                 return true;
 150         }
 151         return false;
 152 }
 153
 154 /****************************************************************************
 155  Core of smb password checking routine. (NTLMv2, LMv2)
 156  Note:  The same code works with both NTLMv2 and LMv2.
 157 ****************************************************************************/
 158
 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)
 166 {
 167         /* Finish the encryption of part_passwd. */
 168         uint8_t kr[16];
 169         uint8_t value_from_encryption[16];
 170         DATA_BLOB client_key_data;
 171
 172         if (part_passwd == NULL) {
 173                 DEBUG(10,("No password set - DISALLOWING access\n"));
 174                 /* No password set - always false */
 175                 return false;
 176         }
 177
 178         if (sec_blob->length != 8) {
 179                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect challenge size (%lu)\n",
 180                           (unsigned long)sec_blob->length));
 181                 return false;
 182         }
 183
 184         if (ntv2_response->length < 24) {
 185                 /* We MUST have more than 16 bytes, or the stuff below will go
 186                    crazy.  No known implementation sends less than the 24 bytes
 187                    for LMv2, let alone NTLMv2. */
 188                 DEBUG(0, ("smb_sess_key_ntlmv2: incorrect password length (%lu)\n",
 189                           (unsigned long)ntv2_response->length));
 190                 return false;
 191         }
 192
 193         client_key_data = data_blob_talloc(mem_ctx, ntv2_response->data+16, ntv2_response->length-16);
 194
 195         if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
 196                 return false;
 197         }
 198
 199         SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
 200         *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
 201         SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
 202         return true;
 203 }
 204
 205 /**
 206  * Compare password hashes against those from the SAM
 207  *
 208  * @param mem_ctx talloc context
 209  * @param client_lanman LANMAN password hash, as supplied by the client
 210  * @param client_nt NT (MD4) password hash, as supplied by the client
 211  * @param username internal Samba username, for log messages
 212  * @param client_username username the client used
 213  * @param client_domain domain name the client used (may be mapped)
 214  * @param stored_lanman LANMAN password hash, as stored on the SAM
 215  * @param stored_nt NT (MD4) password hash, as stored on the SAM
 216  * @param user_sess_key User session key
 217  * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
 218  */
 219
 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)
 227 {
 228         if (stored_nt == NULL) {
 229                 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
 230                          username));
 231         }
 232
 233         if (client_nt && stored_nt) {
 234                 if (memcmp(client_nt->hash, stored_nt->hash, sizeof(stored_nt->hash)) == 0) {
 235                         return NT_STATUS_OK;
 236                 } else {
 237                         DEBUG(3,("ntlm_password_check: Interactive logon: NT password check failed for user %s\n",
 238                                  username));
 239                         return NT_STATUS_WRONG_PASSWORD;
 240                 }
 241
 242         } else if (client_lanman && stored_lanman) {
 243                 if (!lanman_auth) {
 244                         DEBUG(3,("ntlm_password_check: Interactive logon: only LANMAN password supplied for user %s, and LM passwords are disabled!\n",
 245                                  username));
 246                         return NT_STATUS_WRONG_PASSWORD;
 247                 }
 248                 if (strchr_m(username, '@')) {
 249                         return NT_STATUS_NOT_FOUND;
 250                 }
 251
 252                 if (memcmp(client_lanman->hash, stored_lanman->hash, sizeof(stored_lanman->hash)) == 0) {
 253                         return NT_STATUS_OK;
 254                 } else {
 255                         DEBUG(3,("ntlm_password_check: Interactive logon: LANMAN password check failed for user %s\n",
 256                                  username));
 257                         return NT_STATUS_WRONG_PASSWORD;
 258                 }
 259         }
 260         if (strchr_m(username, '@')) {
 261                 return NT_STATUS_NOT_FOUND;
 262         }
 263         return NT_STATUS_WRONG_PASSWORD;
 264 }
 265
 266 /**
 267  * Check a challenge-response password against the value of the NT or
 268  * LM password hash.
 269  *
 270  * @param mem_ctx talloc context
 271  * @param challenge 8-byte challenge.  If all zero, forces plaintext comparison
 272  * @param nt_response 'unicode' NT response to the challenge, or unicode password
 273  * @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
 274  * @param username internal Samba username, for log messages
 275  * @param client_username username the client used
 276  * @param client_domain domain name the client used (may be mapped)
 277  * @param stored_lanman LANMAN ASCII password from our passdb or similar
 278  * @param stored_nt MD4 unicode password from our passdb or similar
 279  * @param user_sess_key User session key
 280  * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
 281  */
 282
 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)
 297 {
 298         const static uint8_t zeros[8];
 299         DATA_BLOB tmp_sess_key;
 300         const char *upper_client_domain = NULL;
 301
 302         if (client_domain != NULL) {
 303                 upper_client_domain = talloc_strdup_upper(mem_ctx, client_domain);
 304                 if (upper_client_domain == NULL) {
 305                         return NT_STATUS_NO_MEMORY;
 306                 }
 307         }
 308
 309         if (stored_nt == NULL) {
 310                 DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n",
 311                          username));
 312         }
 313
 314         *lm_sess_key = data_blob(NULL, 0);
 315         *user_sess_key = data_blob(NULL, 0);
 316
 317         /* Check for cleartext netlogon. Used by Exchange 5.5. */
 318         if ((logon_parameters & MSV1_0_CLEARTEXT_PASSWORD_ALLOWED)
 319             && challenge->length == sizeof(zeros)
 320             && (memcmp(challenge->data, zeros, challenge->length) == 0 )) {
 321                 struct samr_Password client_nt;
 322                 struct samr_Password client_lm;
 323                 char *unix_pw = NULL;
 324                 bool lm_ok;
 325                 size_t converted_size = 0;
 326
 327                 DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
 328                          username));
 329                 mdfour(client_nt.hash, nt_response->data, nt_response->length);
 330
 331                 if (lm_response->length &&
 332                     (convert_string_talloc(mem_ctx, CH_DOS, CH_UNIX,
 333                                           lm_response->data, lm_response->length,
 334                                            (void *)&unix_pw, &converted_size))) {
 335                         if (E_deshash(unix_pw, client_lm.hash)) {
 336                                 lm_ok = true;
 337                         } else {
 338                                 lm_ok = false;
 339                         }
 340                 } else {
 341                         lm_ok = false;
 342                 }
 343                 return hash_password_check(mem_ctx,
 344                                            lanman_auth,
 345                                            lm_ok ? &client_lm : NULL,
 346                                            nt_response->length ? &client_nt : NULL,
 347                                            username,
 348                                            stored_lanman, stored_nt);
 349         }
 350
 351         if (nt_response->length != 0 && nt_response->length < 24) {
 352                 DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n",
 353                          (unsigned long)nt_response->length, username));
 354         }
 355
 356         if (nt_response->length > 24 && stored_nt) {
 357                 /* We have the NT MD4 hash challenge available - see if we can
 358                    use it
 359                 */
 360                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n",
 361                         client_domain ? client_domain : "<NULL>"));
 362                 if (smb_pwd_check_ntlmv2(mem_ctx,
 363                                          nt_response,
 364                                          stored_nt->hash, challenge,
 365                                          client_username,
 366                                          client_domain,
 367                                          false,
 368                                          user_sess_key)) {
 369                         if (user_sess_key->length) {
 370                                 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
 371                         }
 372                         return NT_STATUS_OK;
 373                 }
 374
 375                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n",
 376                         upper_client_domain ? upper_client_domain : "<NULL>"));
 377                 if (smb_pwd_check_ntlmv2(mem_ctx,
 378                                          nt_response,
 379                                          stored_nt->hash, challenge,
 380                                          client_username,
 381                                          upper_client_domain,
 382                                          false,
 383                                          user_sess_key)) {
 384                         if (user_sess_key->length) {
 385                                 *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
 386                         }
 387                         return NT_STATUS_OK;
 388                 }
 389
 390                 DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
 391                 if (smb_pwd_check_ntlmv2(mem_ctx,
 392                                          nt_response,
 393                                          stored_nt->hash, challenge,
 394                                          client_username,
 395                                          "",
 396                                          false,
 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) {
 407                         /* We have the NT MD4 hash challenge available - see if we can
 408                            use it (ie. does it exist in the smbpasswd file).
 409                         */
 410                         DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
 411                         if (smb_pwd_check_ntlmv1(mem_ctx,
 412                                                  nt_response,
 413                                                  stored_nt->hash, challenge,
 414                                                  user_sess_key)) {
 415                                 /* The LM session key for this response is not very secure,
 416                                    so use it only if we otherwise allow LM authentication */
 417
 418                                 if (lanman_auth && stored_lanman) {
 419                                         *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, MIN(8, user_sess_key->length));
 420                                 }
 421                                 return NT_STATUS_OK;
 422                         } else {
 423                                 DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
 424                                          username));
 425                                 return NT_STATUS_WRONG_PASSWORD;
 426                         }
 427                 } else {
 428                         DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
 429                                  username));
 430                         /* no return, because we might pick up LMv2 in the LM field */
 431                 }
 432         }
 433
 434         if (lm_response->length == 0) {
 435                 DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
 436                          username));
 437                 return NT_STATUS_WRONG_PASSWORD;
 438         }
 439
 440         if (lm_response->length < 24) {
 441                 DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n",
 442                          (unsigned long)nt_response->length, username));
 443                 return NT_STATUS_WRONG_PASSWORD;
 444         }
 445
 446         if (!lanman_auth) {
 447                 DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
 448                          username));
 449         } else if (!stored_lanman) {
 450                 DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
 451                          username));
 452         } else if (strchr_m(username, '@')) {
 453                 DEBUG(3,("ntlm_password_check: NO LanMan password allowed for username@realm logins (user: %s)\n",
 454                          username));
 455         } else {
 456                 DEBUG(4,("ntlm_password_check: Checking LM password\n"));
 457                 if (smb_pwd_check_ntlmv1(mem_ctx,
 458                                          lm_response,
 459                                          stored_lanman->hash, challenge,
 460                                          NULL)) {
 461                         /* The session key for this response is still very odd.
 462                            It not very secure, so use it only if we otherwise
 463                            allow LM authentication */
 464
 465                         if (lanman_auth && stored_lanman) {
 466                                 uint8_t first_8_lm_hash[16];
 467                                 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
 468                                 memset(first_8_lm_hash + 8, '\0', 8);
 469                                 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
 470                                 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
 471                         }
 472                         return NT_STATUS_OK;
 473                 }
 474         }
 475
 476         if (!stored_nt) {
 477                 DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
 478                 return NT_STATUS_WRONG_PASSWORD;
 479         }
 480
 481         /* This is for 'LMv2' authentication.  almost NTLMv2 but limited to 24 bytes.
 482            - related to Win9X, legacy NAS pass-though authentication
 483         */
 484         DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n",
 485                 client_domain ? client_domain : "<NULL>"));
 486         if (smb_pwd_check_ntlmv2(mem_ctx,
 487                                  lm_response,
 488                                  stored_nt->hash, challenge,
 489                                  client_username,
 490                                  client_domain,
 491                                  false,
 492                                  &tmp_sess_key)) {
 493                 if (nt_response->length > 24) {
 494                         /* If NTLMv2 authentication has preceeded 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                                             false,
 504                                             user_sess_key);
 505                 } else {
 506                         /* Otherwise, use the LMv2 session key */
 507                         *user_sess_key = tmp_sess_key;
 508                 }
 509                 if (user_sess_key->length) {
 510                         *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
 511                 }
 512                 return NT_STATUS_OK;
 513         }
 514
 515         DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n",
 516                 upper_client_domain ? upper_client_domain : "<NULL>"));
 517         if (smb_pwd_check_ntlmv2(mem_ctx,
 518                                  lm_response,
 519                                  stored_nt->hash, challenge,
 520                                  client_username,
 521                                  upper_client_domain,
 522                                  false,
 523                                  &tmp_sess_key)) {
 524                 if (nt_response->length > 24) {
 525                         /* If NTLMv2 authentication has preceeded us
 526                          * (even if it failed), then use the session
 527                          * key from that.  See the RPC-SAMLOGON
 528                          * torture test */
 529                         smb_sess_key_ntlmv2(mem_ctx,
 530                                             nt_response,
 531                                             stored_nt->hash, challenge,
 532                                             client_username,
 533                                             upper_client_domain,
 534                                             true,
 535                                             user_sess_key);
 536                 } else {
 537                         /* Otherwise, use the LMv2 session key */
 538                         *user_sess_key = tmp_sess_key;
 539                 }
 540                 if (user_sess_key->length) {
 541                         *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
 542                 }
 543                 return NT_STATUS_OK;
 544         }
 545
 546         DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
 547         if (smb_pwd_check_ntlmv2(mem_ctx,
 548                                  lm_response,
 549                                  stored_nt->hash, challenge,
 550                                  client_username,
 551                                  "",
 552                                  false,
 553                                  &tmp_sess_key)) {
 554                 if (nt_response->length > 24) {
 555                         /* If NTLMv2 authentication has preceeded us
 556                          * (even if it failed), then use the session
 557                          * key from that.  See the RPC-SAMLOGON
 558                          * torture test */
 559                         smb_sess_key_ntlmv2(mem_ctx,
 560                                             nt_response,
 561                                             stored_nt->hash, challenge,
 562                                             client_username,
 563                                             "",
 564                                             false,
 565                                             user_sess_key);
 566                 } else {
 567                         /* Otherwise, use the LMv2 session key */
 568                         *user_sess_key = tmp_sess_key;
 569                 }
 570                 if (user_sess_key->length) {
 571                         *lm_sess_key = data_blob_talloc(mem_ctx, user_sess_key->data, MIN(8, user_sess_key->length));
 572                 }
 573                 return NT_STATUS_OK;
 574         }
 575
 576         /* Apparently NT accepts NT responses in the LM field
 577            - I think this is related to Win9X pass-though authentication
 578         */
 579         DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
 580         if (ntlm_auth) {
 581                 if (smb_pwd_check_ntlmv1(mem_ctx,
 582                                          lm_response,
 583                                          stored_nt->hash, challenge,
 584                                          NULL)) {
 585                         /* The session key for this response is still very odd.
 586                            It not very secure, so use it only if we otherwise
 587                            allow LM authentication */
 588
 589                         if (lanman_auth && stored_lanman) {
 590                                 uint8_t first_8_lm_hash[16];
 591                                 memcpy(first_8_lm_hash, stored_lanman->hash, 8);
 592                                 memset(first_8_lm_hash + 8, '\0', 8);
 593                                 *user_sess_key = data_blob_talloc(mem_ctx, first_8_lm_hash, 16);
 594                                 *lm_sess_key = data_blob_talloc(mem_ctx, stored_lanman->hash, 8);
 595                         }
 596                         return NT_STATUS_OK;
 597                 }
 598                 DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
 599         } else {
 600                 DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
 601         }
 602
 603         /* Try and match error codes */
 604         if (strchr_m(username, '@')) {
 605                 return NT_STATUS_NOT_FOUND;
 606         }
 607         return NT_STATUS_WRONG_PASSWORD;
 608 }
 609