source3/auth/check_samsec.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Password and authentication handling
   4    Copyright (C) Andrew Tridgell              1992-2000
   5    Copyright (C) Luke Kenneth Casson Leighton 1996-2000
   6    Copyright (C) Andrew Bartlett              2001-2003
   7    Copyright (C) Gerald Carter                2003
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "../libcli/auth/libcli_auth.h"
  25
  26 #undef DBGC_CLASS
  27 #define DBGC_CLASS DBGC_AUTH
  28
  29 /****************************************************************************
  30  Do a specific test for an smb password being correct, given a smb_password and
  31  the lanman and NT responses.
  32 ****************************************************************************/
  33
  34 static NTSTATUS sam_password_ok(TALLOC_CTX *mem_ctx,
  35                                 const char *username,
  36                                 uint32_t acct_ctrl,
  37                                 const DATA_BLOB *challenge,
  38                                 const uint8_t *lm_pw,
  39                                 const uint8_t *nt_pw,
  40                                 const struct auth_usersupplied_info *user_info,
  41                                 DATA_BLOB *user_sess_key,
  42                                 DATA_BLOB *lm_sess_key)
  43 {
  44         NTSTATUS status;
  45         struct samr_Password _lm_hash, _nt_hash;
  46         struct samr_Password *lm_hash = NULL;
  47         struct samr_Password *nt_hash = NULL;
  48
  49         *user_sess_key = data_blob_null;
  50         *lm_sess_key = data_blob_null;
  51
  52         if (acct_ctrl & ACB_PWNOTREQ) {
  53                 if (lp_null_passwords()) {
  54                         DEBUG(3,("Account for user '%s' has no password and null passwords are allowed.\n", username));
  55                         return NT_STATUS_OK;
  56                 } else {
  57                         DEBUG(3,("Account for user '%s' has no password and null passwords are NOT allowed.\n", username));
  58                         return NT_STATUS_LOGON_FAILURE;
  59                 }
  60         }
  61
  62         if (lm_pw) {
  63                 memcpy(_lm_hash.hash, lm_pw, sizeof(_lm_hash.hash));
  64                 lm_hash = &_lm_hash;
  65         }
  66         if (nt_pw) {
  67                 memcpy(_nt_hash.hash, nt_pw, sizeof(_nt_hash.hash));
  68                 nt_hash = &_nt_hash;
  69         }
  70         switch (user_info->password_state) {
  71         case AUTH_PASSWORD_HASH:
  72                 status = hash_password_check(mem_ctx, lp_lanman_auth(),
  73                                              user_info->password.hash.lanman,
  74                                              user_info->password.hash.nt,
  75                                              username,
  76                                              lm_hash,
  77                                              nt_hash);
  78                 if (NT_STATUS_IS_OK(status)) {
  79                         if (nt_pw) {
  80                                 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
  81                                 if (!user_sess_key->data) {
  82                                         return NT_STATUS_NO_MEMORY;
  83                                 }
  84                                 SMBsesskeygen_ntv1(nt_pw, user_sess_key->data);
  85                         }
  86                 }
  87                 return status;
  88
  89         /* Eventually we should test plaintext passwords in their own
  90          * function, not assuming the caller has done a
  91          * mapping */
  92         case AUTH_PASSWORD_PLAIN:
  93         case AUTH_PASSWORD_RESPONSE:
  94                 return ntlm_password_check(mem_ctx, lp_lanman_auth(),
  95                                            lp_ntlm_auth(),
  96                                            user_info->logon_parameters,
  97                                            challenge,
  98                                            &user_info->password.response.lanman, &user_info->password.response.nt,
  99                                            username,
 100                                            user_info->client.account_name,
 101                                            user_info->client.domain_name,
 102                                            lm_hash,
 103                                            nt_hash,
 104                                            user_sess_key, lm_sess_key);
 105         default:
 106                 DEBUG(0,("user_info constructed for user '%s' was invalid - password_state=%u invalid.\n", username, user_info->password_state));
 107                 return NT_STATUS_INTERNAL_ERROR;
 108         }
 109 }
 110
 111 /****************************************************************************
 112  Check if a user is allowed to logon at this time. Note this is the
 113  servers local time, as logon hours are just specified as a weekly
 114  bitmask.
 115 ****************************************************************************/
 116
 117 static bool logon_hours_ok(struct samu *sampass)
 118 {
 119         /* In logon hours first bit is Sunday from 12AM to 1AM */
 120         const uint8 *hours;
 121         struct tm *utctime;
 122         time_t lasttime;
 123         const char *asct;
 124         uint8 bitmask, bitpos;
 125
 126         hours = pdb_get_hours(sampass);
 127         if (!hours) {
 128                 DEBUG(5,("logon_hours_ok: No hours restrictions for user %s\n",pdb_get_username(sampass)));
 129                 return True;
 130         }
 131
 132         lasttime = time(NULL);
 133         utctime = gmtime(&lasttime);
 134         if (!utctime) {
 135                 DEBUG(1, ("logon_hours_ok: failed to get gmtime. Failing logon for user %s\n",
 136                         pdb_get_username(sampass) ));
 137                 return False;
 138         }
 139
 140         /* find the corresponding byte and bit */
 141         bitpos = (utctime->tm_wday * 24 + utctime->tm_hour) % 168;
 142         bitmask = 1 << (bitpos % 8);
 143
 144         if (! (hours[bitpos/8] & bitmask)) {
 145                 struct tm *t = localtime(&lasttime);
 146                 if (!t) {
 147                         asct = "INVALID TIME";
 148                 } else {
 149                         asct = asctime(t);
 150                         if (!asct) {
 151                                 asct = "INVALID TIME";
 152                         }
 153                 }
 154
 155                 DEBUG(1, ("logon_hours_ok: Account for user %s not allowed to "
 156                           "logon at this time (%s).\n",
 157                           pdb_get_username(sampass), asct ));
 158                 return False;
 159         }
 160
 161         asct = asctime(utctime);
 162         DEBUG(5,("logon_hours_ok: user %s allowed to logon at this time (%s)\n",
 163                 pdb_get_username(sampass), asct ? asct : "UNKNOWN TIME" ));
 164
 165         return True;
 166 }
 167
 168 /****************************************************************************
 169  Do a specific test for a struct samu being valid for this connection
 170  (ie not disabled, expired and the like).
 171 ****************************************************************************/
 172
 173 static NTSTATUS sam_account_ok(TALLOC_CTX *mem_ctx,
 174                                struct samu *sampass,
 175                                const struct auth_usersupplied_info *user_info)
 176 {
 177         uint32  acct_ctrl = pdb_get_acct_ctrl(sampass);
 178         char *workstation_list;
 179         time_t kickoff_time;
 180
 181         DEBUG(4,("sam_account_ok: Checking SMB password for user %s\n",pdb_get_username(sampass)));
 182
 183         /* Quit if the account was disabled. */
 184         if (acct_ctrl & ACB_DISABLED) {
 185                 DEBUG(1,("sam_account_ok: Account for user '%s' was disabled.\n", pdb_get_username(sampass)));
 186                 return NT_STATUS_ACCOUNT_DISABLED;
 187         }
 188
 189         /* Quit if the account was locked out. */
 190         if (acct_ctrl & ACB_AUTOLOCK) {
 191                 DEBUG(1,("sam_account_ok: Account for user %s was locked out.\n", pdb_get_username(sampass)));
 192                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 193         }
 194
 195         /* Quit if the account is not allowed to logon at this time. */
 196         if (! logon_hours_ok(sampass)) {
 197                 return NT_STATUS_INVALID_LOGON_HOURS;
 198         }
 199
 200         /* Test account expire time */
 201
 202         kickoff_time = pdb_get_kickoff_time(sampass);
 203         if (kickoff_time != 0 && time(NULL) > kickoff_time) {
 204                 DEBUG(1,("sam_account_ok: Account for user '%s' has expired.\n", pdb_get_username(sampass)));
 205                 DEBUG(3,("sam_account_ok: Account expired at '%ld' unix time.\n", (long)kickoff_time));
 206                 return NT_STATUS_ACCOUNT_EXPIRED;
 207         }
 208
 209         if (!(pdb_get_acct_ctrl(sampass) & ACB_PWNOEXP) && !(pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ)) {
 210                 time_t must_change_time = pdb_get_pass_must_change_time(sampass);
 211                 time_t last_set_time = pdb_get_pass_last_set_time(sampass);
 212
 213                 /* check for immediate expiry "must change at next logon"
 214                  * for a user account. */
 215                 if (((acct_ctrl & (ACB_WSTRUST|ACB_SVRTRUST)) == 0) && (last_set_time == 0)) {
 216                         DEBUG(1,("sam_account_ok: Account for user '%s' password must change!\n", pdb_get_username(sampass)));
 217                         return NT_STATUS_PASSWORD_MUST_CHANGE;
 218                 }
 219
 220                 /* check for expired password */
 221                 if (must_change_time < time(NULL) && must_change_time != 0) {
 222                         DEBUG(1,("sam_account_ok: Account for user '%s' password expired!\n", pdb_get_username(sampass)));
 223                         DEBUG(1,("sam_account_ok: Password expired at '%s' (%ld) unix time.\n", http_timestring(talloc_tos(), must_change_time), (long)must_change_time));
 224                         return NT_STATUS_PASSWORD_EXPIRED;
 225                 }
 226         }
 227
 228         /* Test workstation. Workstation list is comma separated. */
 229
 230         workstation_list = talloc_strdup(mem_ctx, pdb_get_workstations(sampass));
 231         if (!workstation_list)
 232                 return NT_STATUS_NO_MEMORY;
 233
 234         if (*workstation_list) {
 235                 bool invalid_ws = True;
 236                 char *tok = NULL;
 237                 const char *s = workstation_list;
 238                 char *machine_name = talloc_asprintf(mem_ctx, "%s$", user_info->workstation_name);
 239
 240                 if (machine_name == NULL)
 241                         return NT_STATUS_NO_MEMORY;
 242
 243                 while (next_token_talloc(mem_ctx, &s, &tok, ",")) {
 244                         DEBUG(10,("sam_account_ok: checking for workstation match %s and %s\n",
 245                                   tok, user_info->workstation_name));
 246                         if(strequal(tok, user_info->workstation_name)) {
 247                                 invalid_ws = False;
 248                                 break;
 249                         }
 250                         if (tok[0] == '+') {
 251                                 DEBUG(10,("sam_account_ok: checking for workstation %s in group: %s\n",
 252                                         machine_name, tok + 1));
 253                                 if (user_in_group(machine_name, tok + 1)) {
 254                                         invalid_ws = False;
 255                                         break;
 256                                 }
 257                         }
 258                         TALLOC_FREE(tok);
 259                 }
 260                 TALLOC_FREE(tok);
 261                 TALLOC_FREE(machine_name);
 262
 263                 if (invalid_ws)
 264                         return NT_STATUS_INVALID_WORKSTATION;
 265         }
 266
 267         if (acct_ctrl & ACB_DOMTRUST) {
 268                 DEBUG(2,("sam_account_ok: Domain trust account %s denied by server\n", pdb_get_username(sampass)));
 269                 return NT_STATUS_NOLOGON_INTERDOMAIN_TRUST_ACCOUNT;
 270         }
 271
 272         if (acct_ctrl & ACB_SVRTRUST) {
 273                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT)) {
 274                         DEBUG(2,("sam_account_ok: Server trust account %s denied by server\n", pdb_get_username(sampass)));
 275                         return NT_STATUS_NOLOGON_SERVER_TRUST_ACCOUNT;
 276                 }
 277         }
 278
 279         if (acct_ctrl & ACB_WSTRUST) {
 280                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT)) {
 281                         DEBUG(2,("sam_account_ok: Wksta trust account %s denied by server\n", pdb_get_username(sampass)));
 282                         return NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT;
 283                 }
 284         }
 285         return NT_STATUS_OK;
 286 }
 287
 288 /**
 289  * Check whether the given password is one of the last two
 290  * password history entries. If so, the bad pwcount should
 291  * not be incremented even thought the actual password check
 292  * failed.
 293  */
 294 static bool need_to_increment_bad_pw_count(
 295         const DATA_BLOB *challenge,
 296         struct samu* sampass,
 297         const struct auth_usersupplied_info *user_info)
 298 {
 299         uint8_t i;
 300         const uint8_t *pwhistory;
 301         uint32_t pwhistory_len;
 302         uint32_t policy_pwhistory_len;
 303         uint32_t acct_ctrl;
 304         const char *username;
 305         TALLOC_CTX *mem_ctx = talloc_stackframe();
 306         bool result = true;
 307
 308         pdb_get_account_policy(PDB_POLICY_PASSWORD_HISTORY,
 309                                &policy_pwhistory_len);
 310         if (policy_pwhistory_len == 0) {
 311                 goto done;
 312         }
 313
 314         pwhistory = pdb_get_pw_history(sampass, &pwhistory_len);
 315         if (!pwhistory || pwhistory_len == 0) {
 316                 goto done;
 317         }
 318
 319         acct_ctrl = pdb_get_acct_ctrl(sampass);
 320         username = pdb_get_username(sampass);
 321
 322         for (i=1; i < MIN(MIN(3, policy_pwhistory_len), pwhistory_len); i++) {
 323                 static const uint8_t zero16[SALTED_MD5_HASH_LEN];
 324                 const uint8_t *salt;
 325                 const uint8_t *nt_pw;
 326                 NTSTATUS status;
 327                 DATA_BLOB user_sess_key = data_blob_null;
 328                 DATA_BLOB lm_sess_key = data_blob_null;
 329
 330                 salt = &pwhistory[i*PW_HISTORY_ENTRY_LEN];
 331                 nt_pw = salt + PW_HISTORY_SALT_LEN;
 332
 333                 if (memcmp(zero16, nt_pw, NT_HASH_LEN) == 0) {
 334                         /* skip zero password hash */
 335                         continue;
 336                 }
 337
 338                 if (memcmp(zero16, salt, PW_HISTORY_SALT_LEN) != 0) {
 339                         /* skip nonzero salt (old format entry) */
 340                         continue;
 341                 }
 342
 343                 status = sam_password_ok(mem_ctx,
 344                                          username, acct_ctrl,
 345                                          challenge,
 346                                          NULL, nt_pw,
 347                                          user_info, &user_sess_key, &lm_sess_key);
 348                 if (NT_STATUS_IS_OK(status)) {
 349                         result = false;
 350                         break;
 351                 }
 352         }
 353
 354 done:
 355         TALLOC_FREE(mem_ctx);
 356         return result;
 357 }
 358
 359 /****************************************************************************
 360 check if a username/password is OK assuming the password is a 24 byte
 361 SMB hash supplied in the user_info structure
 362 return an NT_STATUS constant.
 363 ****************************************************************************/
 364
 365 NTSTATUS check_sam_security(const DATA_BLOB *challenge,
 366                             TALLOC_CTX *mem_ctx,
 367                             const struct auth_usersupplied_info *user_info,
 368                             struct auth_serversupplied_info **server_info)
 369 {
 370         struct samu *sampass=NULL;
 371         bool ret;
 372         NTSTATUS nt_status;
 373         NTSTATUS update_login_attempts_status;
 374         DATA_BLOB user_sess_key = data_blob_null;
 375         DATA_BLOB lm_sess_key = data_blob_null;
 376         bool updated_badpw = False;
 377         const char *username;
 378         const uint8_t *nt_pw;
 379         const uint8_t *lm_pw;
 380
 381         /* the returned struct gets kept on the server_info, by means
 382            of a steal further down */
 383
 384         sampass = samu_new(mem_ctx);
 385         if (sampass == NULL) {
 386                 return NT_STATUS_NO_MEMORY;
 387         }
 388
 389         /* get the account information */
 390
 391         become_root();
 392         ret = pdb_getsampwnam(sampass, user_info->mapped.account_name);
 393         unbecome_root();
 394
 395         if (ret == False) {
 396                 DEBUG(3,("check_sam_security: Couldn't find user '%s' in "
 397                          "passdb.\n", user_info->mapped.account_name));
 398                 TALLOC_FREE(sampass);
 399                 return NT_STATUS_NO_SUCH_USER;
 400         }
 401
 402         username = pdb_get_username(sampass);
 403         nt_pw = pdb_get_nt_passwd(sampass);
 404         lm_pw = pdb_get_lanman_passwd(sampass);
 405
 406         /* Quit if the account was locked out. */
 407         if (pdb_get_acct_ctrl(sampass) & ACB_AUTOLOCK) {
 408                 DEBUG(3,("check_sam_security: Account for user %s was locked out.\n", username));
 409                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 410         }
 411
 412         nt_status = sam_password_ok(mem_ctx,
 413                                     username, pdb_get_acct_ctrl(sampass),
 414                                     challenge, lm_pw, nt_pw,
 415                                     user_info, &user_sess_key, &lm_sess_key);
 416
 417         /* Notify passdb backend of login success/failure. If not
 418            NT_STATUS_OK the backend doesn't like the login */
 419
 420         update_login_attempts_status = pdb_update_login_attempts(sampass, NT_STATUS_IS_OK(nt_status));
 421
 422         if (!NT_STATUS_IS_OK(nt_status)) {
 423                 bool increment_bad_pw_count = false;
 424
 425                 if (NT_STATUS_EQUAL(nt_status,NT_STATUS_WRONG_PASSWORD) &&
 426                     pdb_get_acct_ctrl(sampass) & ACB_NORMAL &&
 427                     NT_STATUS_IS_OK(update_login_attempts_status))
 428                 {
 429                         increment_bad_pw_count =
 430                                 need_to_increment_bad_pw_count(
 431                                         challenge, sampass, user_info);
 432                 }
 433
 434                 if (increment_bad_pw_count) {
 435                         pdb_increment_bad_password_count(sampass);
 436                         updated_badpw = True;
 437                 } else {
 438                         pdb_update_bad_password_count(sampass,
 439                                                       &updated_badpw);
 440                 }
 441                 if (updated_badpw){
 442                         NTSTATUS status;
 443
 444                         become_root();
 445                         status = pdb_update_sam_account(sampass);
 446                         unbecome_root();
 447
 448                         if (!NT_STATUS_IS_OK(status)) {
 449                                 DEBUG(1, ("Failed to modify entry: %s\n",
 450                                           nt_errstr(status)));
 451                         }
 452                 }
 453                 goto done;
 454         }
 455
 456         if ((pdb_get_acct_ctrl(sampass) & ACB_NORMAL) &&
 457             (pdb_get_bad_password_count(sampass) > 0)){
 458                 pdb_set_bad_password_count(sampass, 0, PDB_CHANGED);
 459                 pdb_set_bad_password_time(sampass, 0, PDB_CHANGED);
 460                 updated_badpw = True;
 461         }
 462
 463         if (updated_badpw){
 464                 NTSTATUS status;
 465
 466                 become_root();
 467                 status = pdb_update_sam_account(sampass);
 468                 unbecome_root();
 469
 470                 if (!NT_STATUS_IS_OK(status)) {
 471                         DEBUG(1, ("Failed to modify entry: %s\n",
 472                                   nt_errstr(status)));
 473                 }
 474         }
 475
 476         nt_status = sam_account_ok(mem_ctx, sampass, user_info);
 477
 478         if (!NT_STATUS_IS_OK(nt_status)) {
 479                 goto done;
 480         }
 481
 482         become_root();
 483         nt_status = make_server_info_sam(server_info, sampass);
 484         unbecome_root();
 485
 486         TALLOC_FREE(sampass);
 487
 488         if (!NT_STATUS_IS_OK(nt_status)) {
 489                 DEBUG(0,("check_sam_security: make_server_info_sam() failed with '%s'\n", nt_errstr(nt_status)));
 490                 goto done;
 491         }
 492
 493         (*server_info)->user_session_key =
 494                 data_blob_talloc(*server_info, user_sess_key.data,
 495                                  user_sess_key.length);
 496         data_blob_free(&user_sess_key);
 497
 498         (*server_info)->lm_session_key =
 499                 data_blob_talloc(*server_info, lm_sess_key.data,
 500                                  lm_sess_key.length);
 501         data_blob_free(&lm_sess_key);
 502
 503         (*server_info)->nss_token |= user_info->was_mapped;
 504
 505 done:
 506         TALLOC_FREE(sampass);
 507         data_blob_free(&user_sess_key);
 508         data_blob_free(&lm_sess_key);
 509         return nt_status;
 510 }
 511
 512 /* This helper function for winbindd returns a very similar value to
 513  * what a NETLOGON call would give, without the indirection */
 514 NTSTATUS check_sam_security_info3(const DATA_BLOB *challenge,
 515                                   TALLOC_CTX *mem_ctx,
 516                                   const struct auth_usersupplied_info *user_info,
 517                                   struct netr_SamInfo3 **pinfo3)
 518 {
 519         struct auth_serversupplied_info *server_info = NULL;
 520         struct netr_SamInfo3 *info3;
 521         NTSTATUS status;
 522         TALLOC_CTX *frame = talloc_stackframe();
 523
 524         status = check_sam_security(challenge, talloc_tos(), user_info,
 525                                     &server_info);
 526         if (!NT_STATUS_IS_OK(status)) {
 527                 DEBUG(10, ("check_sam_security failed: %s\n",
 528                            nt_errstr(status)));
 529                 goto done;
 530         }
 531
 532         info3 = TALLOC_ZERO_P(mem_ctx, struct netr_SamInfo3);
 533         if (info3 == NULL) {
 534                 status = NT_STATUS_NO_MEMORY;
 535                 goto done;
 536         }
 537
 538         status = serverinfo_to_SamInfo3(server_info, NULL, 0, info3);
 539         if (!NT_STATUS_IS_OK(status)) {
 540                 DEBUG(10, ("serverinfo_to_SamInfo3 failed: %s\n",
 541                            nt_errstr(status)));
 542                 goto done;
 543         }
 544         *pinfo3 = info3;
 545         status =  NT_STATUS_OK;
 546 done:
 547         TALLOC_FREE(frame);
 548         return status;
 549 }