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 #include "passdb.h"
  26
  27 #undef DBGC_CLASS
  28 #define DBGC_CLASS DBGC_AUTH
  29
  30 /****************************************************************************
  31  Do a specific test for an smb password being correct, given a smb_password and
  32  the lanman and NT responses.
  33 ****************************************************************************/
  34
  35 static NTSTATUS sam_password_ok(TALLOC_CTX *mem_ctx,
  36                                 const char *username,
  37                                 uint32_t acct_ctrl,
  38                                 const DATA_BLOB *challenge,
  39                                 const uint8_t *lm_pw,
  40                                 const uint8_t *nt_pw,
  41                                 const struct auth_usersupplied_info *user_info,
  42                                 DATA_BLOB *user_sess_key,
  43                                 DATA_BLOB *lm_sess_key)
  44 {
  45         NTSTATUS status;
  46         struct samr_Password _lm_hash, _nt_hash;
  47         struct samr_Password *lm_hash = NULL;
  48         struct samr_Password *nt_hash = NULL;
  49
  50         *user_sess_key = data_blob_null;
  51         *lm_sess_key = data_blob_null;
  52
  53         if (acct_ctrl & ACB_PWNOTREQ) {
  54                 if (lp_null_passwords()) {
  55                         DEBUG(3,("Account for user '%s' has no password and null passwords are allowed.\n", username));
  56                         return NT_STATUS_OK;
  57                 } else {
  58                         DEBUG(3,("Account for user '%s' has no password and null passwords are NOT allowed.\n", username));
  59                         return NT_STATUS_LOGON_FAILURE;
  60                 }
  61         }
  62
  63         if (lm_pw) {
  64                 memcpy(_lm_hash.hash, lm_pw, sizeof(_lm_hash.hash));
  65                 lm_hash = &_lm_hash;
  66         }
  67         if (nt_pw) {
  68                 memcpy(_nt_hash.hash, nt_pw, sizeof(_nt_hash.hash));
  69                 nt_hash = &_nt_hash;
  70         }
  71         switch (user_info->password_state) {
  72         case AUTH_PASSWORD_HASH:
  73                 status = hash_password_check(mem_ctx, lp_lanman_auth(),
  74                                              user_info->password.hash.lanman,
  75                                              user_info->password.hash.nt,
  76                                              username,
  77                                              lm_hash,
  78                                              nt_hash);
  79                 if (NT_STATUS_IS_OK(status)) {
  80                         if (nt_pw) {
  81                                 *user_sess_key = data_blob_talloc(mem_ctx, NULL, 16);
  82                                 if (!user_sess_key->data) {
  83                                         return NT_STATUS_NO_MEMORY;
  84                                 }
  85                                 SMBsesskeygen_ntv1(nt_pw, user_sess_key->data);
  86                         }
  87                 }
  88                 return status;
  89
  90         /* Eventually we should test plaintext passwords in their own
  91          * function, not assuming the caller has done a
  92          * mapping */
  93         case AUTH_PASSWORD_PLAIN:
  94         case AUTH_PASSWORD_RESPONSE:
  95                 return ntlm_password_check(mem_ctx, lp_lanman_auth(),
  96                                            lp_ntlm_auth(),
  97                                            user_info->logon_parameters,
  98                                            challenge,
  99                                            &user_info->password.response.lanman, &user_info->password.response.nt,
 100                                            username,
 101                                            user_info->client.account_name,
 102                                            user_info->client.domain_name,
 103                                            lm_hash,
 104                                            nt_hash,
 105                                            user_sess_key, lm_sess_key);
 106         default:
 107                 DEBUG(0,("user_info constructed for user '%s' was invalid - password_state=%u invalid.\n", username, user_info->password_state));
 108                 return NT_STATUS_INTERNAL_ERROR;
 109         }
 110 }
 111
 112 /****************************************************************************
 113  Check if a user is allowed to logon at this time. Note this is the
 114  servers local time, as logon hours are just specified as a weekly
 115  bitmask.
 116 ****************************************************************************/
 117
 118 static bool logon_hours_ok(struct samu *sampass)
 119 {
 120         /* In logon hours first bit is Sunday from 12AM to 1AM */
 121         const uint8 *hours;
 122         struct tm *utctime;
 123         time_t lasttime;
 124         const char *asct;
 125         uint8 bitmask, bitpos;
 126
 127         hours = pdb_get_hours(sampass);
 128         if (!hours) {
 129                 DEBUG(5,("logon_hours_ok: No hours restrictions for user %s\n",pdb_get_username(sampass)));
 130                 return True;
 131         }
 132
 133         lasttime = time(NULL);
 134         utctime = gmtime(&lasttime);
 135         if (!utctime) {
 136                 DEBUG(1, ("logon_hours_ok: failed to get gmtime. Failing logon for user %s\n",
 137                         pdb_get_username(sampass) ));
 138                 return False;
 139         }
 140
 141         /* find the corresponding byte and bit */
 142         bitpos = (utctime->tm_wday * 24 + utctime->tm_hour) % 168;
 143         bitmask = 1 << (bitpos % 8);
 144
 145         if (! (hours[bitpos/8] & bitmask)) {
 146                 struct tm *t = localtime(&lasttime);
 147                 if (!t) {
 148                         asct = "INVALID TIME";
 149                 } else {
 150                         asct = asctime(t);
 151                         if (!asct) {
 152                                 asct = "INVALID TIME";
 153                         }
 154                 }
 155
 156                 DEBUG(1, ("logon_hours_ok: Account for user %s not allowed to "
 157                           "logon at this time (%s).\n",
 158                           pdb_get_username(sampass), asct ));
 159                 return False;
 160         }
 161
 162         asct = asctime(utctime);
 163         DEBUG(5,("logon_hours_ok: user %s allowed to logon at this time (%s)\n",
 164                 pdb_get_username(sampass), asct ? asct : "UNKNOWN TIME" ));
 165
 166         return True;
 167 }
 168
 169 /****************************************************************************
 170  Do a specific test for a struct samu being valid for this connection
 171  (ie not disabled, expired and the like).
 172 ****************************************************************************/
 173
 174 static NTSTATUS sam_account_ok(TALLOC_CTX *mem_ctx,
 175                                struct samu *sampass,
 176                                const struct auth_usersupplied_info *user_info)
 177 {
 178         uint32  acct_ctrl = pdb_get_acct_ctrl(sampass);
 179         char *workstation_list;
 180         time_t kickoff_time;
 181
 182         DEBUG(4,("sam_account_ok: Checking SMB password for user %s\n",pdb_get_username(sampass)));
 183
 184         /* Quit if the account was disabled. */
 185         if (acct_ctrl & ACB_DISABLED) {
 186                 DEBUG(1,("sam_account_ok: Account for user '%s' was disabled.\n", pdb_get_username(sampass)));
 187                 return NT_STATUS_ACCOUNT_DISABLED;
 188         }
 189
 190         /* Quit if the account was locked out. */
 191         if (acct_ctrl & ACB_AUTOLOCK) {
 192                 DEBUG(1,("sam_account_ok: Account for user %s was locked out.\n", pdb_get_username(sampass)));
 193                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 194         }
 195
 196         /* Quit if the account is not allowed to logon at this time. */
 197         if (! logon_hours_ok(sampass)) {
 198                 return NT_STATUS_INVALID_LOGON_HOURS;
 199         }
 200
 201         /* Test account expire time */
 202
 203         kickoff_time = pdb_get_kickoff_time(sampass);
 204         if (kickoff_time != 0 && time(NULL) > kickoff_time) {
 205                 DEBUG(1,("sam_account_ok: Account for user '%s' has expired.\n", pdb_get_username(sampass)));
 206                 DEBUG(3,("sam_account_ok: Account expired at '%ld' unix time.\n", (long)kickoff_time));
 207                 return NT_STATUS_ACCOUNT_EXPIRED;
 208         }
 209
 210         if (!(pdb_get_acct_ctrl(sampass) & ACB_PWNOEXP) && !(pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ)) {
 211                 time_t must_change_time = pdb_get_pass_must_change_time(sampass);
 212                 time_t last_set_time = pdb_get_pass_last_set_time(sampass);
 213
 214                 /* check for immediate expiry "must change at next logon"
 215                  * for a user account. */
 216                 if (((acct_ctrl & (ACB_WSTRUST|ACB_SVRTRUST)) == 0) && (last_set_time == 0)) {
 217                         DEBUG(1,("sam_account_ok: Account for user '%s' password must change!\n", pdb_get_username(sampass)));
 218                         return NT_STATUS_PASSWORD_MUST_CHANGE;
 219                 }
 220
 221                 /* check for expired password */
 222                 if (must_change_time < time(NULL) && must_change_time != 0) {
 223                         DEBUG(1,("sam_account_ok: Account for user '%s' password expired!\n", pdb_get_username(sampass)));
 224                         DEBUG(1,("sam_account_ok: Password expired at '%s' (%ld) unix time.\n", http_timestring(talloc_tos(), must_change_time), (long)must_change_time));
 225                         return NT_STATUS_PASSWORD_EXPIRED;
 226                 }
 227         }
 228
 229         /* Test workstation. Workstation list is comma separated. */
 230
 231         workstation_list = talloc_strdup(mem_ctx, pdb_get_workstations(sampass));
 232         if (!workstation_list)
 233                 return NT_STATUS_NO_MEMORY;
 234
 235         if (*workstation_list) {
 236                 bool invalid_ws = True;
 237                 char *tok = NULL;
 238                 const char *s = workstation_list;
 239                 char *machine_name = talloc_asprintf(mem_ctx, "%s$", user_info->workstation_name);
 240
 241                 if (machine_name == NULL)
 242                         return NT_STATUS_NO_MEMORY;
 243
 244                 while (next_token_talloc(mem_ctx, &s, &tok, ",")) {
 245                         DEBUG(10,("sam_account_ok: checking for workstation match %s and %s\n",
 246                                   tok, user_info->workstation_name));
 247                         if(strequal(tok, user_info->workstation_name)) {
 248                                 invalid_ws = False;
 249                                 break;
 250                         }
 251                         if (tok[0] == '+') {
 252                                 DEBUG(10,("sam_account_ok: checking for workstation %s in group: %s\n",
 253                                         machine_name, tok + 1));
 254                                 if (user_in_group(machine_name, tok + 1)) {
 255                                         invalid_ws = False;
 256                                         break;
 257                                 }
 258                         }
 259                         TALLOC_FREE(tok);
 260                 }
 261                 TALLOC_FREE(tok);
 262                 TALLOC_FREE(machine_name);
 263
 264                 if (invalid_ws)
 265                         return NT_STATUS_INVALID_WORKSTATION;
 266         }
 267
 268         if (acct_ctrl & ACB_DOMTRUST) {
 269                 DEBUG(2,("sam_account_ok: Domain trust account %s denied by server\n", pdb_get_username(sampass)));
 270                 return NT_STATUS_NOLOGON_INTERDOMAIN_TRUST_ACCOUNT;
 271         }
 272
 273         if (acct_ctrl & ACB_SVRTRUST) {
 274                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT)) {
 275                         DEBUG(2,("sam_account_ok: Server trust account %s denied by server\n", pdb_get_username(sampass)));
 276                         return NT_STATUS_NOLOGON_SERVER_TRUST_ACCOUNT;
 277                 }
 278         }
 279
 280         if (acct_ctrl & ACB_WSTRUST) {
 281                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT)) {
 282                         DEBUG(2,("sam_account_ok: Wksta trust account %s denied by server\n", pdb_get_username(sampass)));
 283                         return NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT;
 284                 }
 285         }
 286         return NT_STATUS_OK;
 287 }
 288
 289 /**
 290  * Check whether the given password is one of the last two
 291  * password history entries. If so, the bad pwcount should
 292  * not be incremented even thought the actual password check
 293  * failed.
 294  */
 295 static bool need_to_increment_bad_pw_count(
 296         const DATA_BLOB *challenge,
 297         struct samu* sampass,
 298         const struct auth_usersupplied_info *user_info)
 299 {
 300         uint8_t i;
 301         const uint8_t *pwhistory;
 302         uint32_t pwhistory_len;
 303         uint32_t policy_pwhistory_len;
 304         uint32_t acct_ctrl;
 305         const char *username;
 306         TALLOC_CTX *mem_ctx = talloc_stackframe();
 307         bool result = true;
 308
 309         pdb_get_account_policy(PDB_POLICY_PASSWORD_HISTORY,
 310                                &policy_pwhistory_len);
 311         if (policy_pwhistory_len == 0) {
 312                 goto done;
 313         }
 314
 315         pwhistory = pdb_get_pw_history(sampass, &pwhistory_len);
 316         if (!pwhistory || pwhistory_len == 0) {
 317                 goto done;
 318         }
 319
 320         acct_ctrl = pdb_get_acct_ctrl(sampass);
 321         username = pdb_get_username(sampass);
 322
 323         for (i=1; i < MIN(MIN(3, policy_pwhistory_len), pwhistory_len); i++) {
 324                 static const uint8_t zero16[SALTED_MD5_HASH_LEN];
 325                 const uint8_t *salt;
 326                 const uint8_t *nt_pw;
 327                 NTSTATUS status;
 328                 DATA_BLOB user_sess_key = data_blob_null;
 329                 DATA_BLOB lm_sess_key = data_blob_null;
 330
 331                 salt = &pwhistory[i*PW_HISTORY_ENTRY_LEN];
 332                 nt_pw = salt + PW_HISTORY_SALT_LEN;
 333
 334                 if (memcmp(zero16, nt_pw, NT_HASH_LEN) == 0) {
 335                         /* skip zero password hash */
 336                         continue;
 337                 }
 338
 339                 if (memcmp(zero16, salt, PW_HISTORY_SALT_LEN) != 0) {
 340                         /* skip nonzero salt (old format entry) */
 341                         continue;
 342                 }
 343
 344                 status = sam_password_ok(mem_ctx,
 345                                          username, acct_ctrl,
 346                                          challenge,
 347                                          NULL, nt_pw,
 348                                          user_info, &user_sess_key, &lm_sess_key);
 349                 if (NT_STATUS_IS_OK(status)) {
 350                         result = false;
 351                         break;
 352                 }
 353         }
 354
 355 done:
 356         TALLOC_FREE(mem_ctx);
 357         return result;
 358 }
 359
 360 /****************************************************************************
 361 check if a username/password is OK assuming the password is a 24 byte
 362 SMB hash supplied in the user_info structure
 363 return an NT_STATUS constant.
 364 ****************************************************************************/
 365
 366 NTSTATUS check_sam_security(const DATA_BLOB *challenge,
 367                             TALLOC_CTX *mem_ctx,
 368                             const struct auth_usersupplied_info *user_info,
 369                             struct auth_serversupplied_info **server_info)
 370 {
 371         struct samu *sampass=NULL;
 372         bool ret;
 373         NTSTATUS nt_status;
 374         NTSTATUS update_login_attempts_status;
 375         DATA_BLOB user_sess_key = data_blob_null;
 376         DATA_BLOB lm_sess_key = data_blob_null;
 377         bool updated_badpw = False;
 378         const char *username;
 379         const uint8_t *nt_pw;
 380         const uint8_t *lm_pw;
 381
 382         /* the returned struct gets kept on the server_info, by means
 383            of a steal further down */
 384
 385         sampass = samu_new(mem_ctx);
 386         if (sampass == NULL) {
 387                 return NT_STATUS_NO_MEMORY;
 388         }
 389
 390         /* get the account information */
 391
 392         become_root();
 393         ret = pdb_getsampwnam(sampass, user_info->mapped.account_name);
 394         unbecome_root();
 395
 396         if (ret == False) {
 397                 DEBUG(3,("check_sam_security: Couldn't find user '%s' in "
 398                          "passdb.\n", user_info->mapped.account_name));
 399                 TALLOC_FREE(sampass);
 400                 return NT_STATUS_NO_SUCH_USER;
 401         }
 402
 403         username = pdb_get_username(sampass);
 404         nt_pw = pdb_get_nt_passwd(sampass);
 405         lm_pw = pdb_get_lanman_passwd(sampass);
 406
 407         /* Quit if the account was locked out. */
 408         if (pdb_get_acct_ctrl(sampass) & ACB_AUTOLOCK) {
 409                 DEBUG(3,("check_sam_security: Account for user %s was locked out.\n", username));
 410                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 411         }
 412
 413         nt_status = sam_password_ok(mem_ctx,
 414                                     username, pdb_get_acct_ctrl(sampass),
 415                                     challenge, lm_pw, nt_pw,
 416                                     user_info, &user_sess_key, &lm_sess_key);
 417
 418         /* Notify passdb backend of login success/failure. If not
 419            NT_STATUS_OK the backend doesn't like the login */
 420
 421         update_login_attempts_status = pdb_update_login_attempts(sampass, NT_STATUS_IS_OK(nt_status));
 422
 423         if (!NT_STATUS_IS_OK(nt_status)) {
 424                 bool increment_bad_pw_count = false;
 425
 426                 if (NT_STATUS_EQUAL(nt_status,NT_STATUS_WRONG_PASSWORD) &&
 427                     pdb_get_acct_ctrl(sampass) & ACB_NORMAL &&
 428                     NT_STATUS_IS_OK(update_login_attempts_status))
 429                 {
 430                         increment_bad_pw_count =
 431                                 need_to_increment_bad_pw_count(
 432                                         challenge, sampass, user_info);
 433                 }
 434
 435                 if (increment_bad_pw_count) {
 436                         pdb_increment_bad_password_count(sampass);
 437                         updated_badpw = True;
 438                 } else {
 439                         pdb_update_bad_password_count(sampass,
 440                                                       &updated_badpw);
 441                 }
 442                 if (updated_badpw){
 443                         NTSTATUS status;
 444
 445                         become_root();
 446                         status = pdb_update_sam_account(sampass);
 447                         unbecome_root();
 448
 449                         if (!NT_STATUS_IS_OK(status)) {
 450                                 DEBUG(1, ("Failed to modify entry: %s\n",
 451                                           nt_errstr(status)));
 452                         }
 453                 }
 454                 goto done;
 455         }
 456
 457         if ((pdb_get_acct_ctrl(sampass) & ACB_NORMAL) &&
 458             (pdb_get_bad_password_count(sampass) > 0)){
 459                 pdb_set_bad_password_count(sampass, 0, PDB_CHANGED);
 460                 pdb_set_bad_password_time(sampass, 0, PDB_CHANGED);
 461                 updated_badpw = True;
 462         }
 463
 464         if (updated_badpw){
 465                 NTSTATUS status;
 466
 467                 become_root();
 468                 status = pdb_update_sam_account(sampass);
 469                 unbecome_root();
 470
 471                 if (!NT_STATUS_IS_OK(status)) {
 472                         DEBUG(1, ("Failed to modify entry: %s\n",
 473                                   nt_errstr(status)));
 474                 }
 475         }
 476
 477         nt_status = sam_account_ok(mem_ctx, sampass, user_info);
 478
 479         if (!NT_STATUS_IS_OK(nt_status)) {
 480                 goto done;
 481         }
 482
 483         become_root();
 484         nt_status = make_server_info_sam(server_info, sampass);
 485         unbecome_root();
 486
 487         TALLOC_FREE(sampass);
 488
 489         if (!NT_STATUS_IS_OK(nt_status)) {
 490                 DEBUG(0,("check_sam_security: make_server_info_sam() failed with '%s'\n", nt_errstr(nt_status)));
 491                 goto done;
 492         }
 493
 494         (*server_info)->user_session_key =
 495                 data_blob_talloc(*server_info, user_sess_key.data,
 496                                  user_sess_key.length);
 497         data_blob_free(&user_sess_key);
 498
 499         (*server_info)->lm_session_key =
 500                 data_blob_talloc(*server_info, lm_sess_key.data,
 501                                  lm_sess_key.length);
 502         data_blob_free(&lm_sess_key);
 503
 504         (*server_info)->nss_token |= user_info->was_mapped;
 505
 506 done:
 507         TALLOC_FREE(sampass);
 508         data_blob_free(&user_sess_key);
 509         data_blob_free(&lm_sess_key);
 510         return nt_status;
 511 }
 512
 513 /* This helper function for winbindd returns a very similar value to
 514  * what a NETLOGON call would give, without the indirection */
 515 NTSTATUS check_sam_security_info3(const DATA_BLOB *challenge,
 516                                   TALLOC_CTX *mem_ctx,
 517                                   const struct auth_usersupplied_info *user_info,
 518                                   struct netr_SamInfo3 **pinfo3)
 519 {
 520         struct auth_serversupplied_info *server_info = NULL;
 521         struct netr_SamInfo3 *info3;
 522         NTSTATUS status;
 523         TALLOC_CTX *frame = talloc_stackframe();
 524
 525         status = check_sam_security(challenge, talloc_tos(), user_info,
 526                                     &server_info);
 527         if (!NT_STATUS_IS_OK(status)) {
 528                 DEBUG(10, ("check_sam_security failed: %s\n",
 529                            nt_errstr(status)));
 530                 goto done;
 531         }
 532
 533         info3 = TALLOC_ZERO_P(mem_ctx, struct netr_SamInfo3);
 534         if (info3 == NULL) {
 535                 status = NT_STATUS_NO_MEMORY;
 536                 goto done;
 537         }
 538
 539         status = serverinfo_to_SamInfo3(server_info, NULL, 0, info3);
 540         if (!NT_STATUS_IS_OK(status)) {
 541                 DEBUG(10, ("serverinfo_to_SamInfo3 failed: %s\n",
 542                            nt_errstr(status)));
 543                 goto done;
 544         }
 545         *pinfo3 = info3;
 546         status =  NT_STATUS_OK;
 547 done:
 548         TALLOC_FREE(frame);
 549         return status;
 550 }