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         }
 106         return NT_STATUS_INVALID_PARAMETER;
 107 }
 108
 109 /****************************************************************************
 110  Check if a user is allowed to logon at this time. Note this is the
 111  servers local time, as logon hours are just specified as a weekly
 112  bitmask.
 113 ****************************************************************************/
 114
 115 static bool logon_hours_ok(struct samu *sampass)
 116 {
 117         /* In logon hours first bit is Sunday from 12AM to 1AM */
 118         const uint8 *hours;
 119         struct tm *utctime;
 120         time_t lasttime;
 121         const char *asct;
 122         uint8 bitmask, bitpos;
 123
 124         hours = pdb_get_hours(sampass);
 125         if (!hours) {
 126                 DEBUG(5,("logon_hours_ok: No hours restrictions for user %s\n",pdb_get_username(sampass)));
 127                 return True;
 128         }
 129
 130         lasttime = time(NULL);
 131         utctime = gmtime(&lasttime);
 132         if (!utctime) {
 133                 DEBUG(1, ("logon_hours_ok: failed to get gmtime. Failing logon for user %s\n",
 134                         pdb_get_username(sampass) ));
 135                 return False;
 136         }
 137
 138         /* find the corresponding byte and bit */
 139         bitpos = (utctime->tm_wday * 24 + utctime->tm_hour) % 168;
 140         bitmask = 1 << (bitpos % 8);
 141
 142         if (! (hours[bitpos/8] & bitmask)) {
 143                 struct tm *t = localtime(&lasttime);
 144                 if (!t) {
 145                         asct = "INVALID TIME";
 146                 } else {
 147                         asct = asctime(t);
 148                         if (!asct) {
 149                                 asct = "INVALID TIME";
 150                         }
 151                 }
 152
 153                 DEBUG(1, ("logon_hours_ok: Account for user %s not allowed to "
 154                           "logon at this time (%s).\n",
 155                           pdb_get_username(sampass), asct ));
 156                 return False;
 157         }
 158
 159         asct = asctime(utctime);
 160         DEBUG(5,("logon_hours_ok: user %s allowed to logon at this time (%s)\n",
 161                 pdb_get_username(sampass), asct ? asct : "UNKNOWN TIME" ));
 162
 163         return True;
 164 }
 165
 166 /****************************************************************************
 167  Do a specific test for a struct samu being valid for this connection
 168  (ie not disabled, expired and the like).
 169 ****************************************************************************/
 170
 171 static NTSTATUS sam_account_ok(TALLOC_CTX *mem_ctx,
 172                                struct samu *sampass,
 173                                const struct auth_usersupplied_info *user_info)
 174 {
 175         uint32  acct_ctrl = pdb_get_acct_ctrl(sampass);
 176         char *workstation_list;
 177         time_t kickoff_time;
 178
 179         DEBUG(4,("sam_account_ok: Checking SMB password for user %s\n",pdb_get_username(sampass)));
 180
 181         /* Quit if the account was disabled. */
 182         if (acct_ctrl & ACB_DISABLED) {
 183                 DEBUG(1,("sam_account_ok: Account for user '%s' was disabled.\n", pdb_get_username(sampass)));
 184                 return NT_STATUS_ACCOUNT_DISABLED;
 185         }
 186
 187         /* Quit if the account was locked out. */
 188         if (acct_ctrl & ACB_AUTOLOCK) {
 189                 DEBUG(1,("sam_account_ok: Account for user %s was locked out.\n", pdb_get_username(sampass)));
 190                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 191         }
 192
 193         /* Quit if the account is not allowed to logon at this time. */
 194         if (! logon_hours_ok(sampass)) {
 195                 return NT_STATUS_INVALID_LOGON_HOURS;
 196         }
 197
 198         /* Test account expire time */
 199
 200         kickoff_time = pdb_get_kickoff_time(sampass);
 201         if (kickoff_time != 0 && time(NULL) > kickoff_time) {
 202                 DEBUG(1,("sam_account_ok: Account for user '%s' has expired.\n", pdb_get_username(sampass)));
 203                 DEBUG(3,("sam_account_ok: Account expired at '%ld' unix time.\n", (long)kickoff_time));
 204                 return NT_STATUS_ACCOUNT_EXPIRED;
 205         }
 206
 207         if (!(pdb_get_acct_ctrl(sampass) & ACB_PWNOEXP) && !(pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ)) {
 208                 time_t must_change_time = pdb_get_pass_must_change_time(sampass);
 209                 time_t last_set_time = pdb_get_pass_last_set_time(sampass);
 210
 211                 /* check for immediate expiry "must change at next logon"
 212                  * for a user account. */
 213                 if (((acct_ctrl & (ACB_WSTRUST|ACB_SVRTRUST)) == 0) && (last_set_time == 0)) {
 214                         DEBUG(1,("sam_account_ok: Account for user '%s' password must change!\n", pdb_get_username(sampass)));
 215                         return NT_STATUS_PASSWORD_MUST_CHANGE;
 216                 }
 217
 218                 /* check for expired password */
 219                 if (must_change_time < time(NULL) && must_change_time != 0) {
 220                         DEBUG(1,("sam_account_ok: Account for user '%s' password expired!\n", pdb_get_username(sampass)));
 221                         DEBUG(1,("sam_account_ok: Password expired at '%s' (%ld) unix time.\n", http_timestring(talloc_tos(), must_change_time), (long)must_change_time));
 222                         return NT_STATUS_PASSWORD_EXPIRED;
 223                 }
 224         }
 225
 226         /* Test workstation. Workstation list is comma separated. */
 227
 228         workstation_list = talloc_strdup(mem_ctx, pdb_get_workstations(sampass));
 229         if (!workstation_list)
 230                 return NT_STATUS_NO_MEMORY;
 231
 232         if (*workstation_list) {
 233                 bool invalid_ws = True;
 234                 char *tok = NULL;
 235                 const char *s = workstation_list;
 236                 char *machine_name = talloc_asprintf(mem_ctx, "%s$", user_info->workstation_name);
 237
 238                 if (machine_name == NULL)
 239                         return NT_STATUS_NO_MEMORY;
 240
 241                 while (next_token_talloc(mem_ctx, &s, &tok, ",")) {
 242                         DEBUG(10,("sam_account_ok: checking for workstation match %s and %s\n",
 243                                   tok, user_info->workstation_name));
 244                         if(strequal(tok, user_info->workstation_name)) {
 245                                 invalid_ws = False;
 246                                 break;
 247                         }
 248                         if (tok[0] == '+') {
 249                                 DEBUG(10,("sam_account_ok: checking for workstation %s in group: %s\n",
 250                                         machine_name, tok + 1));
 251                                 if (user_in_group(machine_name, tok + 1)) {
 252                                         invalid_ws = False;
 253                                         break;
 254                                 }
 255                         }
 256                         TALLOC_FREE(tok);
 257                 }
 258                 TALLOC_FREE(tok);
 259                 TALLOC_FREE(machine_name);
 260
 261                 if (invalid_ws)
 262                         return NT_STATUS_INVALID_WORKSTATION;
 263         }
 264
 265         if (acct_ctrl & ACB_DOMTRUST) {
 266                 DEBUG(2,("sam_account_ok: Domain trust account %s denied by server\n", pdb_get_username(sampass)));
 267                 return NT_STATUS_NOLOGON_INTERDOMAIN_TRUST_ACCOUNT;
 268         }
 269
 270         if (acct_ctrl & ACB_SVRTRUST) {
 271                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT)) {
 272                         DEBUG(2,("sam_account_ok: Server trust account %s denied by server\n", pdb_get_username(sampass)));
 273                         return NT_STATUS_NOLOGON_SERVER_TRUST_ACCOUNT;
 274                 }
 275         }
 276
 277         if (acct_ctrl & ACB_WSTRUST) {
 278                 if (!(user_info->logon_parameters & MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT)) {
 279                         DEBUG(2,("sam_account_ok: Wksta trust account %s denied by server\n", pdb_get_username(sampass)));
 280                         return NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT;
 281                 }
 282         }
 283         return NT_STATUS_OK;
 284 }
 285
 286 /**
 287  * Check whether the given password is one of the last two
 288  * password history entries. If so, the bad pwcount should
 289  * not be incremented even thought the actual password check
 290  * failed.
 291  */
 292 static bool need_to_increment_bad_pw_count(
 293         const DATA_BLOB *challenge,
 294         struct samu* sampass,
 295         const struct auth_usersupplied_info *user_info)
 296 {
 297         uint8_t i;
 298         const uint8_t *pwhistory;
 299         uint32_t pwhistory_len;
 300         uint32_t policy_pwhistory_len;
 301         uint32_t acct_ctrl;
 302         const char *username;
 303         TALLOC_CTX *mem_ctx = talloc_stackframe();
 304         bool result = true;
 305
 306         pdb_get_account_policy(PDB_POLICY_PASSWORD_HISTORY,
 307                                &policy_pwhistory_len);
 308         if (policy_pwhistory_len == 0) {
 309                 goto done;
 310         }
 311
 312         pwhistory = pdb_get_pw_history(sampass, &pwhistory_len);
 313         if (!pwhistory || pwhistory_len == 0) {
 314                 goto done;
 315         }
 316
 317         acct_ctrl = pdb_get_acct_ctrl(sampass);
 318         username = pdb_get_username(sampass);
 319
 320         for (i=1; i < MIN(MIN(3, policy_pwhistory_len), pwhistory_len); i++) {
 321                 static const uint8_t zero16[SALTED_MD5_HASH_LEN];
 322                 const uint8_t *salt;
 323                 const uint8_t *nt_pw;
 324                 NTSTATUS status;
 325                 DATA_BLOB user_sess_key = data_blob_null;
 326                 DATA_BLOB lm_sess_key = data_blob_null;
 327
 328                 salt = &pwhistory[i*PW_HISTORY_ENTRY_LEN];
 329                 nt_pw = salt + PW_HISTORY_SALT_LEN;
 330
 331                 if (memcmp(zero16, nt_pw, NT_HASH_LEN) == 0) {
 332                         /* skip zero password hash */
 333                         continue;
 334                 }
 335
 336                 if (memcmp(zero16, salt, PW_HISTORY_SALT_LEN) != 0) {
 337                         /* skip nonzero salt (old format entry) */
 338                         continue;
 339                 }
 340
 341                 status = sam_password_ok(mem_ctx,
 342                                          username, acct_ctrl,
 343                                          challenge,
 344                                          NULL, nt_pw,
 345                                          user_info, &user_sess_key, &lm_sess_key);
 346                 if (NT_STATUS_IS_OK(status)) {
 347                         result = false;
 348                         break;
 349                 }
 350         }
 351
 352 done:
 353         TALLOC_FREE(mem_ctx);
 354         return result;
 355 }
 356
 357 /****************************************************************************
 358 check if a username/password is OK assuming the password is a 24 byte
 359 SMB hash supplied in the user_info structure
 360 return an NT_STATUS constant.
 361 ****************************************************************************/
 362
 363 NTSTATUS check_sam_security(const DATA_BLOB *challenge,
 364                             TALLOC_CTX *mem_ctx,
 365                             const struct auth_usersupplied_info *user_info,
 366                             struct auth_serversupplied_info **server_info)
 367 {
 368         struct samu *sampass=NULL;
 369         bool ret;
 370         NTSTATUS nt_status;
 371         NTSTATUS update_login_attempts_status;
 372         DATA_BLOB user_sess_key = data_blob_null;
 373         DATA_BLOB lm_sess_key = data_blob_null;
 374         bool updated_autolock = False, updated_badpw = False;
 375         const char *username;
 376         const uint8_t *nt_pw;
 377         const uint8_t *lm_pw;
 378
 379         /* the returned struct gets kept on the server_info, by means
 380            of a steal further down */
 381
 382         sampass = samu_new(mem_ctx);
 383         if (sampass == NULL) {
 384                 return NT_STATUS_NO_MEMORY;
 385         }
 386
 387         /* get the account information */
 388
 389         become_root();
 390         ret = pdb_getsampwnam(sampass, user_info->mapped.account_name);
 391         unbecome_root();
 392
 393         if (ret == False) {
 394                 DEBUG(3,("check_sam_security: Couldn't find user '%s' in "
 395                          "passdb.\n", user_info->mapped.account_name));
 396                 TALLOC_FREE(sampass);
 397                 return NT_STATUS_NO_SUCH_USER;
 398         }
 399
 400         username = pdb_get_username(sampass);
 401         nt_pw = pdb_get_nt_passwd(sampass);
 402         lm_pw = pdb_get_lanman_passwd(sampass);
 403
 404         /* see if autolock flag needs to be updated */
 405         if (pdb_get_acct_ctrl(sampass) & ACB_NORMAL)
 406                 pdb_update_autolock_flag(sampass, &updated_autolock);
 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_autolock || 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_autolock || 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 }