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 "auth.h"
  25 #include "../libcli/auth/libcli_auth.h"
  26 #include "passdb.h"
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_AUTH
  30
  31 /****************************************************************************
  32  Do a specific test for an smb password being correct, given a smb_password and
  33  the lanman and NT responses.
  34 ****************************************************************************/
  35
  36 static NTSTATUS sam_password_ok(TALLOC_CTX *mem_ctx,
  37                                 const char *username,
  38                                 uint32_t acct_ctrl,
  39                                 const DATA_BLOB *challenge,
  40                                 const uint8_t *lm_pw,
  41                                 const uint8_t *nt_pw,
  42                                 const struct auth_usersupplied_info *user_info,
  43                                 DATA_BLOB *user_sess_key,
  44                                 DATA_BLOB *lm_sess_key)
  45 {
  46         NTSTATUS status;
  47         struct samr_Password _lm_hash, _nt_hash;
  48         struct samr_Password *lm_hash = NULL;
  49         struct samr_Password *nt_hash = NULL;
  50
  51         *user_sess_key = data_blob_null;
  52         *lm_sess_key = data_blob_null;
  53
  54         if (acct_ctrl & ACB_PWNOTREQ) {
  55                 if (lp_null_passwords()) {
  56                         DEBUG(3,("Account for user '%s' has no password and null passwords are allowed.\n", username));
  57                         return NT_STATUS_OK;
  58                 } else {
  59                         DEBUG(3,("Account for user '%s' has no password and null passwords are NOT allowed.\n", username));
  60                         return NT_STATUS_LOGON_FAILURE;
  61                 }
  62         }
  63
  64         if (lm_pw) {
  65                 memcpy(_lm_hash.hash, lm_pw, sizeof(_lm_hash.hash));
  66                 lm_hash = &_lm_hash;
  67         }
  68         if (nt_pw) {
  69                 memcpy(_nt_hash.hash, nt_pw, sizeof(_nt_hash.hash));
  70                 nt_hash = &_nt_hash;
  71         }
  72         switch (user_info->password_state) {
  73         case AUTH_PASSWORD_HASH:
  74                 status = hash_password_check(mem_ctx, lp_lanman_auth(),
  75                                              user_info->password.hash.lanman,
  76                                              user_info->password.hash.nt,
  77                                              username,
  78                                              lm_hash,
  79                                              nt_hash);
  80                 if (NT_STATUS_IS_OK(status)) {
  81                         if (nt_pw) {
  82                                 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
  83                                 if (!user_sess_key->data) {
  84                                         return NT_STATUS_NO_MEMORY;
  85                                 }
  86                                 SMBsesskeygen_ntv1(nt_pw, user_sess_key->data);
  87                         }
  88                 }
  89                 return status;
  90
  91         /* Eventually we should test plaintext passwords in their own
  92          * function, not assuming the caller has done a
  93          * mapping */
  94         case AUTH_PASSWORD_PLAIN:
  95         case AUTH_PASSWORD_RESPONSE:
  96                 return ntlm_password_check(mem_ctx, lp_lanman_auth(),
  97                                            lp_ntlm_auth(),
  98                                            user_info->logon_parameters,
  99                                            challenge,
 100                                            &user_info->password.response.lanman, &user_info->password.response.nt,
 101                                            username,
 102                                            user_info->client.account_name,
 103                                            user_info->client.domain_name,
 104                                            lm_hash,
 105                                            nt_hash,
 106                                            user_sess_key, lm_sess_key);
 107         default:
 108                 DEBUG(0,("user_info constructed for user '%s' was invalid - password_state=%u invalid.\n", username, user_info->password_state));
 109                 return NT_STATUS_INTERNAL_ERROR;
 110         }
 111 }
 112
 113 /****************************************************************************
 114  Check if a user is allowed to logon at this time. Note this is the
 115  servers local time, as logon hours are just specified as a weekly
 116  bitmask.
 117 ****************************************************************************/
 118
 119 static bool logon_hours_ok(struct samu *sampass)
 120 {
 121         /* In logon hours first bit is Sunday from 12AM to 1AM */
 122         const uint8_t *hours;
 123         struct tm *utctime;
 124         time_t lasttime;
 125         const char *asct;
 126         uint8_t bitmask, bitpos;
 127
 128         hours = pdb_get_hours(sampass);
 129         if (!hours) {
 130                 DEBUG(5,("logon_hours_ok: No hours restrictions for user %s\n",pdb_get_username(sampass)));
 131                 return True;
 132         }
 133
 134         lasttime = time(NULL);
 135         utctime = gmtime(&lasttime);
 136         if (!utctime) {
 137                 DEBUG(1, ("logon_hours_ok: failed to get gmtime. Failing logon for user %s\n",
 138                         pdb_get_username(sampass) ));
 139                 return False;
 140         }
 141
 142         /* find the corresponding byte and bit */
 143         bitpos = (utctime->tm_wday * 24 + utctime->tm_hour) % 168;
 144         bitmask = 1 << (bitpos % 8);
 145
 146         if (! (hours[bitpos/8] & bitmask)) {
 147                 struct tm *t = localtime(&lasttime);
 148                 if (!t) {
 149                         asct = "INVALID TIME";
 150                 } else {
 151                         asct = asctime(t);
 152                         if (!asct) {
 153                                 asct = "INVALID TIME";
 154                         }
 155                 }
 156
 157                 DEBUG(1, ("logon_hours_ok: Account for user %s not allowed to "
 158                           "logon at this time (%s).\n",
 159                           pdb_get_username(sampass), asct ));
 160                 return False;
 161         }
 162
 163         asct = asctime(utctime);
 164         DEBUG(5,("logon_hours_ok: user %s allowed to logon at this time (%s)\n",
 165                 pdb_get_username(sampass), asct ? asct : "UNKNOWN TIME" ));
 166
 167         return True;
 168 }
 169
 170 /****************************************************************************
 171  Do a specific test for a struct samu being valid for this connection
 172  (ie not disabled, expired and the like).
 173 ****************************************************************************/
 174
 175 static NTSTATUS sam_account_ok(TALLOC_CTX *mem_ctx,
 176                                struct samu *sampass,
 177                                const struct auth_usersupplied_info *user_info)
 178 {
 179         uint32_t acct_ctrl = pdb_get_acct_ctrl(sampass);
 180         char *workstation_list;
 181         time_t kickoff_time;
 182
 183         DEBUG(4,("sam_account_ok: Checking SMB password for user %s\n",pdb_get_username(sampass)));
 184
 185         /* Quit if the account was disabled. */
 186         if (acct_ctrl & ACB_DISABLED) {
 187                 DEBUG(1,("sam_account_ok: Account for user '%s' was disabled.\n", pdb_get_username(sampass)));
 188                 return NT_STATUS_ACCOUNT_DISABLED;
 189         }
 190
 191         /* Quit if the account was locked out. */
 192         if (acct_ctrl & ACB_AUTOLOCK) {
 193                 DEBUG(1,("sam_account_ok: Account for user %s was locked out.\n", pdb_get_username(sampass)));
 194                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 195         }
 196
 197         /* Quit if the account is not allowed to logon at this time. */
 198         if (! logon_hours_ok(sampass)) {
 199                 return NT_STATUS_INVALID_LOGON_HOURS;
 200         }
 201
 202         /* Test account expire time */
 203
 204         kickoff_time = pdb_get_kickoff_time(sampass);
 205         if (kickoff_time != 0 && time(NULL) > kickoff_time) {
 206                 DEBUG(1,("sam_account_ok: Account for user '%s' has expired.\n", pdb_get_username(sampass)));
 207                 DEBUG(3,("sam_account_ok: Account expired at '%ld' unix time.\n", (long)kickoff_time));
 208                 return NT_STATUS_ACCOUNT_EXPIRED;
 209         }
 210
 211         if (!(pdb_get_acct_ctrl(sampass) & ACB_PWNOEXP) && !(pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ)) {
 212                 time_t must_change_time = pdb_get_pass_must_change_time(sampass);
 213                 time_t last_set_time = pdb_get_pass_last_set_time(sampass);
 214
 215                 /* check for immediate expiry "must change at next logon"
 216                  * for a user account. */
 217                 if (((acct_ctrl & (ACB_WSTRUST|ACB_SVRTRUST)) == 0) && (last_set_time == 0)) {
 218                         DEBUG(1,("sam_account_ok: Account for user '%s' password must change!\n", pdb_get_username(sampass)));
 219                         return NT_STATUS_PASSWORD_MUST_CHANGE;
 220                 }
 221
 222                 /* check for expired password */
 223                 if (must_change_time < time(NULL) && must_change_time != 0) {
 224                         DEBUG(1,("sam_account_ok: Account for user '%s' password expired!\n", pdb_get_username(sampass)));
 225                         DEBUG(1,("sam_account_ok: Password expired at '%s' (%ld) unix time.\n", http_timestring(talloc_tos(), must_change_time), (long)must_change_time));
 226                         return NT_STATUS_PASSWORD_EXPIRED;
 227                 }
 228         }
 229
 230         /* Test workstation. Workstation list is comma separated. */
 231
 232         workstation_list = talloc_strdup(mem_ctx, pdb_get_workstations(sampass));
 233         if (!workstation_list)
 234                 return NT_STATUS_NO_MEMORY;
 235
 236         if (*workstation_list) {
 237                 bool invalid_ws = True;
 238                 char *tok = NULL;
 239                 const char *s = workstation_list;
 240                 char *machine_name = talloc_asprintf(mem_ctx, "%s$", user_info->workstation_name);
 241
 242                 if (machine_name == NULL)
 243                         return NT_STATUS_NO_MEMORY;
 244
 245                 while (next_token_talloc(mem_ctx, &s, &tok, ",")) {
 246                         DEBUG(10,("sam_account_ok: checking for workstation match %s and %s\n",
 247                                   tok, user_info->workstation_name));
 248                         if(strequal(tok, user_info->workstation_name)) {
 249                                 invalid_ws = False;
 250                                 break;
 251                         }
 252                         if (tok[0] == '+') {
 253                                 DEBUG(10,("sam_account_ok: checking for workstation %s in group: %s\n",
 254                                         machine_name, tok + 1));
 255                                 if (user_in_group(machine_name, tok + 1)) {
 256                                         invalid_ws = False;
 257                                         break;
 258                                 }
 259                         }
 260                         TALLOC_FREE(tok);
 261                 }
 262                 TALLOC_FREE(tok);
 263                 TALLOC_FREE(machine_name);
 264
 265                 if (invalid_ws)
 266                         return NT_STATUS_INVALID_WORKSTATION;
 267         }
 268
 269         if (acct_ctrl & ACB_DOMTRUST) {
 270                 DEBUG(2,("sam_account_ok: Domain trust account %s denied by server\n", pdb_get_username(sampass)));
 271                 return NT_STATUS_NOLOGON_INTERDOMAIN_TRUST_ACCOUNT;
 272         }
 273
 274         if (acct_ctrl & ACB_SVRTRUST) {
 275                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT)) {
 276                         DEBUG(2,("sam_account_ok: Server trust account %s denied by server\n", pdb_get_username(sampass)));
 277                         return NT_STATUS_NOLOGON_SERVER_TRUST_ACCOUNT;
 278                 }
 279         }
 280
 281         if (acct_ctrl & ACB_WSTRUST) {
 282                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT)) {
 283                         DEBUG(2,("sam_account_ok: Wksta trust account %s denied by server\n", pdb_get_username(sampass)));
 284                         return NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT;
 285                 }
 286         }
 287         return NT_STATUS_OK;
 288 }
 289
 290 /**
 291  * Check whether the given password is one of the last two
 292  * password history entries. If so, the bad pwcount should
 293  * not be incremented even thought the actual password check
 294  * failed.
 295  */
 296 static bool need_to_increment_bad_pw_count(
 297         const DATA_BLOB *challenge,
 298         struct samu* sampass,
 299         const struct auth_usersupplied_info *user_info)
 300 {
 301         uint8_t i;
 302         const uint8_t *pwhistory;
 303         uint32_t pwhistory_len;
 304         uint32_t policy_pwhistory_len;
 305         uint32_t acct_ctrl;
 306         const char *username;
 307         TALLOC_CTX *mem_ctx = talloc_stackframe();
 308         bool result = true;
 309
 310         pdb_get_account_policy(PDB_POLICY_PASSWORD_HISTORY,
 311                                &policy_pwhistory_len);
 312         if (policy_pwhistory_len == 0) {
 313                 goto done;
 314         }
 315
 316         pwhistory = pdb_get_pw_history(sampass, &pwhistory_len);
 317         if (!pwhistory || pwhistory_len == 0) {
 318                 goto done;
 319         }
 320
 321         acct_ctrl = pdb_get_acct_ctrl(sampass);
 322         username = pdb_get_username(sampass);
 323
 324         for (i=1; i < MIN(MIN(3, policy_pwhistory_len), pwhistory_len); i++) {
 325                 static const uint8_t zero16[SALTED_MD5_HASH_LEN];
 326                 const uint8_t *salt;
 327                 const uint8_t *nt_pw;
 328                 NTSTATUS status;
 329                 DATA_BLOB user_sess_key = data_blob_null;
 330                 DATA_BLOB lm_sess_key = data_blob_null;
 331
 332                 salt = &pwhistory[i*PW_HISTORY_ENTRY_LEN];
 333                 nt_pw = salt + PW_HISTORY_SALT_LEN;
 334
 335                 if (memcmp(zero16, nt_pw, NT_HASH_LEN) == 0) {
 336                         /* skip zero password hash */
 337                         continue;
 338                 }
 339
 340                 if (memcmp(zero16, salt, PW_HISTORY_SALT_LEN) != 0) {
 341                         /* skip nonzero salt (old format entry) */
 342                         continue;
 343                 }
 344
 345                 status = sam_password_ok(mem_ctx,
 346                                          username, acct_ctrl,
 347                                          challenge,
 348                                          NULL, nt_pw,
 349                                          user_info, &user_sess_key, &lm_sess_key);
 350                 if (NT_STATUS_IS_OK(status)) {
 351                         result = false;
 352                         break;
 353                 }
 354         }
 355
 356 done:
 357         TALLOC_FREE(mem_ctx);
 358         return result;
 359 }
 360
 361 /****************************************************************************
 362 check if a username/password is OK assuming the password is a 24 byte
 363 SMB hash supplied in the user_info structure
 364 return an NT_STATUS constant.
 365 ****************************************************************************/
 366
 367 NTSTATUS check_sam_security(const DATA_BLOB *challenge,
 368                             TALLOC_CTX *mem_ctx,
 369                             const struct auth_usersupplied_info *user_info,
 370                             struct auth_serversupplied_info **server_info)
 371 {
 372         struct samu *sampass=NULL;
 373         bool ret;
 374         NTSTATUS nt_status;
 375         NTSTATUS update_login_attempts_status;
 376         DATA_BLOB user_sess_key = data_blob_null;
 377         DATA_BLOB lm_sess_key = data_blob_null;
 378         bool updated_badpw = False;
 379         const char *username;
 380         const uint8_t *nt_pw;
 381         const uint8_t *lm_pw;
 382         uint32_t acct_ctrl;
 383
 384         /* the returned struct gets kept on the server_info, by means
 385            of a steal further down */
 386
 387         sampass = samu_new(mem_ctx);
 388         if (sampass == NULL) {
 389                 return NT_STATUS_NO_MEMORY;
 390         }
 391
 392         /* get the account information */
 393
 394         become_root();
 395         ret = pdb_getsampwnam(sampass, user_info->mapped.account_name);
 396         unbecome_root();
 397
 398         if (ret == False) {
 399                 DEBUG(3,("check_sam_security: Couldn't find user '%s' in "
 400                          "passdb.\n", user_info->mapped.account_name));
 401                 TALLOC_FREE(sampass);
 402                 return NT_STATUS_NO_SUCH_USER;
 403         }
 404
 405         acct_ctrl = pdb_get_acct_ctrl(sampass);
 406         username = pdb_get_username(sampass);
 407         nt_pw = pdb_get_nt_passwd(sampass);
 408         lm_pw = pdb_get_lanman_passwd(sampass);
 409
 410         /* Quit if the account was locked out. */
 411         if (acct_ctrl & ACB_AUTOLOCK) {
 412                 DEBUG(3,("check_sam_security: Account for user %s was locked out.\n", username));
 413                 TALLOC_FREE(sampass);
 414                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 415         }
 416
 417         nt_status = sam_password_ok(mem_ctx,
 418                                     username, acct_ctrl,
 419                                     challenge, lm_pw, nt_pw,
 420                                     user_info, &user_sess_key, &lm_sess_key);
 421
 422         /* Notify passdb backend of login success/failure. If not
 423            NT_STATUS_OK the backend doesn't like the login */
 424
 425         update_login_attempts_status = pdb_update_login_attempts(sampass, NT_STATUS_IS_OK(nt_status));
 426
 427         if (!NT_STATUS_IS_OK(nt_status)) {
 428                 bool increment_bad_pw_count = false;
 429
 430                 if (NT_STATUS_EQUAL(nt_status,NT_STATUS_WRONG_PASSWORD) &&
 431                     (acct_ctrl & ACB_NORMAL) &&
 432                     NT_STATUS_IS_OK(update_login_attempts_status))
 433                 {
 434                         increment_bad_pw_count =
 435                                 need_to_increment_bad_pw_count(
 436                                         challenge, sampass, user_info);
 437                 }
 438
 439                 if (increment_bad_pw_count) {
 440                         pdb_increment_bad_password_count(sampass);
 441                         updated_badpw = True;
 442                 } else {
 443                         pdb_update_bad_password_count(sampass,
 444                                                       &updated_badpw);
 445                 }
 446                 if (updated_badpw){
 447                         NTSTATUS status;
 448
 449                         become_root();
 450                         status = pdb_update_sam_account(sampass);
 451                         unbecome_root();
 452
 453                         if (!NT_STATUS_IS_OK(status)) {
 454                                 DEBUG(1, ("Failed to modify entry: %s\n",
 455                                           nt_errstr(status)));
 456                         }
 457                 }
 458                 goto done;
 459         }
 460
 461         /*
 462          * We must only reset the bad password count if the login was
 463          * successful, including checking account policies
 464          */
 465         nt_status = sam_account_ok(mem_ctx, sampass, user_info);
 466         if (!NT_STATUS_IS_OK(nt_status)) {
 467                 goto done;
 468         }
 469
 470         if ((acct_ctrl & ACB_NORMAL) &&
 471             (pdb_get_bad_password_count(sampass) > 0)){
 472                 NTSTATUS status;
 473
 474                 pdb_set_bad_password_count(sampass, 0, PDB_CHANGED);
 475                 pdb_set_bad_password_time(sampass, 0, PDB_CHANGED);
 476
 477                 become_root();
 478                 status = pdb_update_sam_account(sampass);
 479                 unbecome_root();
 480
 481                 if (!NT_STATUS_IS_OK(status)) {
 482                         DEBUG(1, ("Failed to modify entry: %s\n",
 483                                   nt_errstr(status)));
 484                 }
 485         }
 486
 487         become_root();
 488         nt_status = make_server_info_sam(mem_ctx, sampass, server_info);
 489         unbecome_root();
 490
 491         TALLOC_FREE(sampass);
 492
 493         if (!NT_STATUS_IS_OK(nt_status)) {
 494                 DEBUG(0,("check_sam_security: make_server_info_sam() failed with '%s'\n", nt_errstr(nt_status)));
 495                 goto done;
 496         }
 497
 498         (*server_info)->session_key =
 499                 data_blob_talloc(*server_info, user_sess_key.data,
 500                                  user_sess_key.length);
 501         data_blob_free(&user_sess_key);
 502
 503         (*server_info)->lm_session_key =
 504                 data_blob_talloc(*server_info, lm_sess_key.data,
 505                                  lm_sess_key.length);
 506         data_blob_free(&lm_sess_key);
 507
 508         (*server_info)->nss_token |= user_info->was_mapped;
 509
 510 done:
 511         TALLOC_FREE(sampass);
 512         data_blob_free(&user_sess_key);
 513         data_blob_free(&lm_sess_key);
 514         return nt_status;
 515 }
 516
 517 /* This helper function for winbindd returns a very similar value to
 518  * what a NETLOGON call would give, without the indirection */
 519 NTSTATUS check_sam_security_info3(const DATA_BLOB *challenge,
 520                                   TALLOC_CTX *mem_ctx,
 521                                   const struct auth_usersupplied_info *user_info,
 522                                   struct netr_SamInfo3 **pinfo3)
 523 {
 524         struct auth_serversupplied_info *server_info = NULL;
 525         struct netr_SamInfo3 *info3;
 526         NTSTATUS status;
 527         TALLOC_CTX *frame = talloc_stackframe();
 528
 529         status = check_sam_security(challenge, talloc_tos(), user_info,
 530                                     &server_info);
 531         if (!NT_STATUS_IS_OK(status)) {
 532                 DEBUG(10, ("check_sam_security failed: %s\n",
 533                            nt_errstr(status)));
 534                 goto done;
 535         }
 536
 537         info3 = talloc_zero(mem_ctx, struct netr_SamInfo3);
 538         if (info3 == NULL) {
 539                 status = NT_STATUS_NO_MEMORY;
 540                 goto done;
 541         }
 542
 543         status = serverinfo_to_SamInfo3(server_info, info3);
 544         if (!NT_STATUS_IS_OK(status)) {
 545                 DEBUG(10, ("serverinfo_to_SamInfo3 failed: %s\n",
 546                            nt_errstr(status)));
 547                 goto done;
 548         }
 549         *pinfo3 = info3;
 550         status =  NT_STATUS_OK;
 551 done:
 552         TALLOC_FREE(frame);
 553         return status;
 554 }