source3/smbd/password.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Password and authentication handling
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 2007.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22
  23 /* users from session setup */
  24 static char *session_userlist = NULL;
  25 /* workgroup from session setup. */
  26 static char *session_workgroup = NULL;
  27
  28 /* this holds info on user ids that are already validated for this VC */
  29 static user_struct *validated_users;
  30 static int next_vuid = VUID_OFFSET;
  31 static int num_validated_vuids;
  32
  33 enum server_allocated_state { SERVER_ALLOCATED_REQUIRED_YES,
  34                                 SERVER_ALLOCATED_REQUIRED_NO,
  35                                 SERVER_ALLOCATED_REQUIRED_ANY};
  36
  37 static user_struct *get_valid_user_struct_internal(uint16 vuid,
  38                         enum server_allocated_state server_allocated)
  39 {
  40         user_struct *usp;
  41         int count=0;
  42
  43         if (vuid == UID_FIELD_INVALID)
  44                 return NULL;
  45
  46         for (usp=validated_users;usp;usp=usp->next,count++) {
  47                 if (vuid == usp->vuid) {
  48                         switch (server_allocated) {
  49                                 case SERVER_ALLOCATED_REQUIRED_YES:
  50                                         if (usp->server_info == NULL) {
  51                                                 continue;
  52                                         }
  53                                         break;
  54                                 case SERVER_ALLOCATED_REQUIRED_NO:
  55                                         if (usp->server_info != NULL) {
  56                                                 continue;
  57                                         }
  58                                 case SERVER_ALLOCATED_REQUIRED_ANY:
  59                                         break;
  60                         }
  61                         if (count > 10) {
  62                                 DLIST_PROMOTE(validated_users, usp);
  63                         }
  64                         return usp;
  65                 }
  66         }
  67
  68         return NULL;
  69 }
  70
  71 /****************************************************************************
  72  Check if a uid has been validated, and return an pointer to the user_struct
  73  if it has. NULL if not. vuid is biased by an offset. This allows us to
  74  tell random client vuid's (normally zero) from valid vuids.
  75 ****************************************************************************/
  76
  77 user_struct *get_valid_user_struct(uint16 vuid)
  78 {
  79         return get_valid_user_struct_internal(vuid,
  80                         SERVER_ALLOCATED_REQUIRED_YES);
  81 }
  82
  83 bool is_partial_auth_vuid(uint16 vuid)
  84 {
  85         if (vuid == UID_FIELD_INVALID) {
  86                 return False;
  87         }
  88         return get_valid_user_struct_internal(vuid,
  89                         SERVER_ALLOCATED_REQUIRED_NO) ? True : False;
  90 }
  91
  92 /****************************************************************************
  93  Get the user struct of a partial NTLMSSP login
  94 ****************************************************************************/
  95
  96 user_struct *get_partial_auth_user_struct(uint16 vuid)
  97 {
  98         return get_valid_user_struct_internal(vuid,
  99                         SERVER_ALLOCATED_REQUIRED_NO);
 100 }
 101
 102 /****************************************************************************
 103  Invalidate a uid.
 104 ****************************************************************************/
 105
 106 void invalidate_vuid(uint16 vuid)
 107 {
 108         user_struct *vuser = NULL;
 109
 110         if (vuid == UID_FIELD_INVALID) {
 111                 return;
 112         }
 113
 114         vuser = get_valid_user_struct_internal(vuid,
 115                         SERVER_ALLOCATED_REQUIRED_ANY);
 116         if (vuser == NULL) {
 117                 return;
 118         }
 119
 120         session_yield(vuser);
 121
 122         if (vuser->auth_ntlmssp_state) {
 123                 auth_ntlmssp_end(&vuser->auth_ntlmssp_state);
 124         }
 125
 126         DLIST_REMOVE(validated_users, vuser);
 127
 128         /* clear the vuid from the 'cache' on each connection, and
 129            from the vuid 'owner' of connections */
 130         conn_clear_vuid_caches(vuid);
 131
 132         TALLOC_FREE(vuser);
 133         num_validated_vuids--;
 134 }
 135
 136 /****************************************************************************
 137  Invalidate all vuid entries for this process.
 138 ****************************************************************************/
 139
 140 void invalidate_all_vuids(void)
 141 {
 142         while (validated_users != NULL) {
 143                 invalidate_vuid(validated_users->vuid);
 144         }
 145 }
 146
 147 /****************************************************
 148  Create a new partial auth user struct.
 149 *****************************************************/
 150
 151 int register_initial_vuid(void)
 152 {
 153         user_struct *vuser;
 154
 155         /* Paranoia check. */
 156         if(lp_security() == SEC_SHARE) {
 157                 smb_panic("register_initial_vuid: "
 158                         "Tried to register uid in security=share");
 159         }
 160
 161         /* Limit allowed vuids to 16bits - VUID_OFFSET. */
 162         if (num_validated_vuids >= 0xFFFF-VUID_OFFSET) {
 163                 return UID_FIELD_INVALID;
 164         }
 165
 166         if((vuser = talloc_zero(NULL, user_struct)) == NULL) {
 167                 DEBUG(0,("register_initial_vuid: "
 168                                 "Failed to talloc users struct!\n"));
 169                 return UID_FIELD_INVALID;
 170         }
 171
 172         /* Allocate a free vuid. Yes this is a linear search... */
 173         while( get_valid_user_struct_internal(next_vuid,
 174                         SERVER_ALLOCATED_REQUIRED_ANY) != NULL ) {
 175                 next_vuid++;
 176                 /* Check for vuid wrap. */
 177                 if (next_vuid == UID_FIELD_INVALID) {
 178                         next_vuid = VUID_OFFSET;
 179                 }
 180         }
 181
 182         DEBUG(10,("register_initial_vuid: allocated vuid = %u\n",
 183                 (unsigned int)next_vuid ));
 184
 185         vuser->vuid = next_vuid;
 186
 187         /*
 188          * This happens in an unfinished NTLMSSP session setup. We
 189          * need to allocate a vuid between the first and second calls
 190          * to NTLMSSP.
 191          */
 192         next_vuid++;
 193         num_validated_vuids++;
 194
 195         DLIST_ADD(validated_users, vuser);
 196         return vuser->vuid;
 197 }
 198
 199 static int register_homes_share(const char *username)
 200 {
 201         int result;
 202         struct passwd *pwd;
 203
 204         result = lp_servicenumber(username);
 205         if (result != -1) {
 206                 DEBUG(3, ("Using static (or previously created) service for "
 207                           "user '%s'; path = '%s'\n", username,
 208                           lp_pathname(result)));
 209                 return result;
 210         }
 211
 212         pwd = getpwnam_alloc(talloc_tos(), username);
 213
 214         if ((pwd == NULL) || (pwd->pw_dir[0] == '\0')) {
 215                 DEBUG(3, ("No home directory defined for user '%s'\n",
 216                           username));
 217                 TALLOC_FREE(pwd);
 218                 return -1;
 219         }
 220
 221         DEBUG(3, ("Adding homes service for user '%s' using home directory: "
 222                   "'%s'\n", username, pwd->pw_dir));
 223
 224         result = add_home_service(username, username, pwd->pw_dir);
 225
 226         TALLOC_FREE(pwd);
 227         return result;
 228 }
 229
 230 /**
 231  *  register that a valid login has been performed, establish 'session'.
 232  *  @param server_info The token returned from the authentication process.
 233  *   (now 'owned' by register_existing_vuid)
 234  *
 235  *  @param session_key The User session key for the login session (now also
 236  *  'owned' by register_existing_vuid)
 237  *
 238  *  @param respose_blob The NT challenge-response, if available.  (May be
 239  *  freed after this call)
 240  *
 241  *  @param smb_name The untranslated name of the user
 242  *
 243  *  @return Newly allocated vuid, biased by an offset. (This allows us to
 244  *   tell random client vuid's (normally zero) from valid vuids.)
 245  *
 246  */
 247
 248 int register_existing_vuid(uint16 vuid,
 249                         auth_serversupplied_info *server_info,
 250                         DATA_BLOB response_blob,
 251                         const char *smb_name)
 252 {
 253         fstring tmp;
 254         user_struct *vuser;
 255
 256         vuser = get_partial_auth_user_struct(vuid);
 257         if (!vuser) {
 258                 goto fail;
 259         }
 260
 261         /* Use this to keep tabs on all our info from the authentication */
 262         vuser->server_info = talloc_move(vuser, &server_info);
 263
 264         /* This is a potentially untrusted username */
 265         alpha_strcpy(tmp, smb_name, ". _-$", sizeof(tmp));
 266
 267         vuser->server_info->sanitized_username = talloc_strdup(
 268                 vuser->server_info, tmp);
 269
 270         DEBUG(10,("register_existing_vuid: (%u,%u) %s %s %s guest=%d\n",
 271                   (unsigned int)vuser->server_info->utok.uid,
 272                   (unsigned int)vuser->server_info->utok.gid,
 273                   vuser->server_info->unix_name,
 274                   vuser->server_info->sanitized_username,
 275                   pdb_get_domain(vuser->server_info->sam_account),
 276                   vuser->server_info->guest ));
 277
 278         DEBUG(3, ("register_existing_vuid: User name: %s\t"
 279                   "Real name: %s\n", vuser->server_info->unix_name,
 280                   pdb_get_fullname(vuser->server_info->sam_account)));
 281
 282         if (!vuser->server_info->ptok) {
 283                 DEBUG(1, ("register_existing_vuid: server_info does not "
 284                         "contain a user_token - cannot continue\n"));
 285                 goto fail;
 286         }
 287
 288         DEBUG(3,("register_existing_vuid: UNIX uid %d is UNIX user %s, "
 289                 "and will be vuid %u\n", (int)vuser->server_info->utok.uid,
 290                  vuser->server_info->unix_name, vuser->vuid));
 291
 292         next_vuid++;
 293         num_validated_vuids++;
 294
 295         if (!session_claim(vuser)) {
 296                 DEBUG(1, ("register_existing_vuid: Failed to claim session "
 297                         "for vuid=%d\n",
 298                         vuser->vuid));
 299                 goto fail;
 300         }
 301
 302         /* Register a home dir service for this user if
 303         (a) This is not a guest connection,
 304         (b) we have a home directory defined
 305         (c) there s not an existing static share by that name
 306         If a share exists by this name (autoloaded or not) reuse it . */
 307
 308         vuser->homes_snum = -1;
 309
 310         if (!vuser->server_info->guest) {
 311                 vuser->homes_snum = register_homes_share(
 312                         vuser->server_info->unix_name);
 313         }
 314
 315         if (srv_is_signing_negotiated() && !vuser->server_info->guest &&
 316                         !srv_signing_started()) {
 317                 /* Try and turn on server signing on the first non-guest
 318                  * sessionsetup. */
 319                 srv_set_signing(vuser->server_info->user_session_key, response_blob);
 320         }
 321
 322         /* fill in the current_user_info struct */
 323         set_current_user_info(
 324                 vuser->server_info->sanitized_username,
 325                 vuser->server_info->unix_name,
 326                 pdb_get_fullname(vuser->server_info->sam_account),
 327                 pdb_get_domain(vuser->server_info->sam_account));
 328
 329         return vuser->vuid;
 330
 331   fail:
 332
 333         if (vuser) {
 334                 invalidate_vuid(vuid);
 335         }
 336         return UID_FIELD_INVALID;
 337 }
 338
 339 /****************************************************************************
 340  Add a name to the session users list.
 341 ****************************************************************************/
 342
 343 void add_session_user(const char *user)
 344 {
 345         struct passwd *pw;
 346         char *tmp;
 347
 348         pw = Get_Pwnam_alloc(talloc_tos(), user);
 349
 350         if (pw == NULL) {
 351                 return;
 352         }
 353
 354         if (session_userlist == NULL) {
 355                 session_userlist = SMB_STRDUP(pw->pw_name);
 356                 goto done;
 357         }
 358
 359         if (in_list(pw->pw_name,session_userlist,False) ) {
 360                 goto done;
 361         }
 362
 363         if (strlen(session_userlist) > 128 * 1024) {
 364                 DEBUG(3,("add_session_user: session userlist already "
 365                          "too large.\n"));
 366                 goto done;
 367         }
 368
 369         if (asprintf(&tmp, "%s %s", session_userlist, pw->pw_name) == -1) {
 370                 DEBUG(3, ("asprintf failed\n"));
 371                 goto done;
 372         }
 373
 374         SAFE_FREE(session_userlist);
 375         session_userlist = tmp;
 376  done:
 377         TALLOC_FREE(pw);
 378 }
 379
 380 /****************************************************************************
 381  In security=share mode we need to store the client workgroup, as that's
 382   what Vista uses for the NTLMv2 calculation.
 383 ****************************************************************************/
 384
 385 void add_session_workgroup(const char *workgroup)
 386 {
 387         if (session_workgroup) {
 388                 SAFE_FREE(session_workgroup);
 389         }
 390         session_workgroup = smb_xstrdup(workgroup);
 391 }
 392
 393 /****************************************************************************
 394  In security=share mode we need to return the client workgroup, as that's
 395   what Vista uses for the NTLMv2 calculation.
 396 ****************************************************************************/
 397
 398 const char *get_session_workgroup(void)
 399 {
 400         return session_workgroup;
 401 }
 402
 403 /****************************************************************************
 404  Check if a user is in a netgroup user list. If at first we don't succeed,
 405  try lower case.
 406 ****************************************************************************/
 407
 408 bool user_in_netgroup(const char *user, const char *ngname)
 409 {
 410 #ifdef HAVE_NETGROUP
 411         static char *mydomain = NULL;
 412         fstring lowercase_user;
 413
 414         if (mydomain == NULL)
 415                 yp_get_default_domain(&mydomain);
 416
 417         if(mydomain == NULL) {
 418                 DEBUG(5,("Unable to get default yp domain, "
 419                         "let's try without specifying it\n"));
 420         }
 421
 422         DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 423                 user, mydomain?mydomain:"(ANY)", ngname));
 424
 425         if (innetgr(ngname, NULL, user, mydomain)) {
 426                 DEBUG(5,("user_in_netgroup: Found\n"));
 427                 return (True);
 428         } else {
 429
 430                 /*
 431                  * Ok, innetgr is case sensitive. Try once more with lowercase
 432                  * just in case. Attempt to fix #703. JRA.
 433                  */
 434
 435                 fstrcpy(lowercase_user, user);
 436                 strlower_m(lowercase_user);
 437
 438                 DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 439                         lowercase_user, mydomain?mydomain:"(ANY)", ngname));
 440
 441                 if (innetgr(ngname, NULL, lowercase_user, mydomain)) {
 442                         DEBUG(5,("user_in_netgroup: Found\n"));
 443                         return (True);
 444                 }
 445         }
 446 #endif /* HAVE_NETGROUP */
 447         return False;
 448 }
 449
 450 /****************************************************************************
 451  Check if a user is in a user list - can check combinations of UNIX
 452  and netgroup lists.
 453 ****************************************************************************/
 454
 455 bool user_in_list(const char *user,const char **list)
 456 {
 457         if (!list || !*list)
 458                 return False;
 459
 460         DEBUG(10,("user_in_list: checking user %s in list\n", user));
 461
 462         while (*list) {
 463
 464                 DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
 465                           user, *list));
 466
 467                 /*
 468                  * Check raw username.
 469                  */
 470                 if (strequal(user, *list))
 471                         return(True);
 472
 473                 /*
 474                  * Now check to see if any combination
 475                  * of UNIX and netgroups has been specified.
 476                  */
 477
 478                 if(**list == '@') {
 479                         /*
 480                          * Old behaviour. Check netgroup list
 481                          * followed by UNIX list.
 482                          */
 483                         if(user_in_netgroup(user, *list +1))
 484                                 return True;
 485                         if(user_in_group(user, *list +1))
 486                                 return True;
 487                 } else if (**list == '+') {
 488
 489                         if((*(*list +1)) == '&') {
 490                                 /*
 491                                  * Search UNIX list followed by netgroup.
 492                                  */
 493                                 if(user_in_group(user, *list +2))
 494                                         return True;
 495                                 if(user_in_netgroup(user, *list +2))
 496                                         return True;
 497
 498                         } else {
 499
 500                                 /*
 501                                  * Just search UNIX list.
 502                                  */
 503
 504                                 if(user_in_group(user, *list +1))
 505                                         return True;
 506                         }
 507
 508                 } else if (**list == '&') {
 509
 510                         if(*(*list +1) == '+') {
 511                                 /*
 512                                  * Search netgroup list followed by UNIX list.
 513                                  */
 514                                 if(user_in_netgroup(user, *list +2))
 515                                         return True;
 516                                 if(user_in_group(user, *list +2))
 517                                         return True;
 518                         } else {
 519                                 /*
 520                                  * Just search netgroup list.
 521                                  */
 522                                 if(user_in_netgroup(user, *list +1))
 523                                         return True;
 524                         }
 525                 }
 526
 527                 list++;
 528         }
 529         return(False);
 530 }
 531
 532 /****************************************************************************
 533  Check if a username is valid.
 534 ****************************************************************************/
 535
 536 static bool user_ok(const char *user, int snum)
 537 {
 538         char **valid, **invalid;
 539         bool ret;
 540
 541         valid = invalid = NULL;
 542         ret = True;
 543
 544         if (lp_invalid_users(snum)) {
 545                 invalid = str_list_copy(talloc_tos(), lp_invalid_users(snum));
 546                 if (invalid &&
 547                     str_list_substitute(invalid, "%S", lp_servicename(snum))) {
 548
 549                         /* This is used in sec=share only, so no current user
 550                          * around to pass to str_list_sub_basic() */
 551
 552                         if ( invalid && str_list_sub_basic(invalid, "", "") ) {
 553                                 ret = !user_in_list(user,
 554                                                     (const char **)invalid);
 555                         }
 556                 }
 557         }
 558         TALLOC_FREE(invalid);
 559
 560         if (ret && lp_valid_users(snum)) {
 561                 valid = str_list_copy(talloc_tos(), lp_valid_users(snum));
 562                 if ( valid &&
 563                      str_list_substitute(valid, "%S", lp_servicename(snum)) ) {
 564
 565                         /* This is used in sec=share only, so no current user
 566                          * around to pass to str_list_sub_basic() */
 567
 568                         if ( valid && str_list_sub_basic(valid, "", "") ) {
 569                                 ret = user_in_list(user, (const char **)valid);
 570                         }
 571                 }
 572         }
 573         TALLOC_FREE(valid);
 574
 575         if (ret && lp_onlyuser(snum)) {
 576                 char **user_list = str_list_make_v3(
 577                         talloc_tos(), lp_username(snum), NULL);
 578                 if (user_list &&
 579                     str_list_substitute(user_list, "%S",
 580                                         lp_servicename(snum))) {
 581                         ret = user_in_list(user, (const char **)user_list);
 582                 }
 583                 TALLOC_FREE(user_list);
 584         }
 585
 586         return(ret);
 587 }
 588
 589 /****************************************************************************
 590  Validate a group username entry. Return the username or NULL.
 591 ****************************************************************************/
 592
 593 static char *validate_group(char *group, DATA_BLOB password,int snum)
 594 {
 595 #ifdef HAVE_NETGROUP
 596         {
 597                 char *host, *user, *domain;
 598                 setnetgrent(group);
 599                 while (getnetgrent(&host, &user, &domain)) {
 600                         if (user) {
 601                                 if (user_ok(user, snum) &&
 602                                     password_ok(user,password)) {
 603                                         endnetgrent();
 604                                         return(user);
 605                                 }
 606                         }
 607                 }
 608                 endnetgrent();
 609         }
 610 #endif
 611
 612 #ifdef HAVE_GETGRENT
 613         {
 614                 struct group *gptr;
 615                 setgrent();
 616                 while ((gptr = (struct group *)getgrent())) {
 617                         if (strequal(gptr->gr_name,group))
 618                                 break;
 619                 }
 620
 621                 /*
 622                  * As user_ok can recurse doing a getgrent(), we must
 623                  * copy the member list onto the heap before
 624                  * use. Bug pointed out by leon@eatworms.swmed.edu.
 625                  */
 626
 627                 if (gptr) {
 628                         char *member_list = NULL;
 629                         size_t list_len = 0;
 630                         char *member;
 631                         int i;
 632
 633                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 634                                 list_len += strlen(gptr->gr_mem[i])+1;
 635                         }
 636                         list_len++;
 637
 638                         member_list = (char *)SMB_MALLOC(list_len);
 639                         if (!member_list) {
 640                                 endgrent();
 641                                 return NULL;
 642                         }
 643
 644                         *member_list = '\0';
 645                         member = member_list;
 646
 647                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 648                                 size_t member_len = strlen(gptr->gr_mem[i])+1;
 649
 650                                 DEBUG(10,("validate_group: = gr_mem = "
 651                                           "%s\n", gptr->gr_mem[i]));
 652
 653                                 safe_strcpy(member, gptr->gr_mem[i],
 654                                         list_len - (member-member_list));
 655                                 member += member_len;
 656                         }
 657
 658                         endgrent();
 659
 660                         member = member_list;
 661                         while (*member) {
 662                                 if (user_ok(member,snum) &&
 663                                     password_ok(member,password)) {
 664                                         char *name = talloc_strdup(talloc_tos(),
 665                                                                 member);
 666                                         SAFE_FREE(member_list);
 667                                         return name;
 668                                 }
 669
 670                                 DEBUG(10,("validate_group = member = %s\n",
 671                                           member));
 672
 673                                 member += strlen(member) + 1;
 674                         }
 675
 676                         SAFE_FREE(member_list);
 677                 } else {
 678                         endgrent();
 679                         return NULL;
 680                 }
 681         }
 682 #endif
 683         return(NULL);
 684 }
 685
 686 /****************************************************************************
 687  Check for authority to login to a service with a given username/password.
 688  Note this is *NOT* used when logging on using sessionsetup_and_X.
 689 ****************************************************************************/
 690
 691 bool authorise_login(int snum, fstring user, DATA_BLOB password,
 692                      bool *guest)
 693 {
 694         bool ok = False;
 695
 696 #ifdef DEBUG_PASSWORD
 697         DEBUG(100,("authorise_login: checking authorisation on "
 698                    "user=%s pass=%s\n", user,password.data));
 699 #endif
 700
 701         *guest = False;
 702
 703         /* there are several possibilities:
 704                 1) login as the given user with given password
 705                 2) login as a previously registered username with the given
 706                    password
 707                 3) login as a session list username with the given password
 708                 4) login as a previously validated user/password pair
 709                 5) login as the "user =" user with given password
 710                 6) login as the "user =" user with no password
 711                    (guest connection)
 712                 7) login as guest user with no password
 713
 714                 if the service is guest_only then steps 1 to 5 are skipped
 715         */
 716
 717         /* now check the list of session users */
 718         if (!ok) {
 719                 char *auser;
 720                 char *user_list = NULL;
 721                 char *saveptr;
 722
 723                 if ( session_userlist )
 724                         user_list = SMB_STRDUP(session_userlist);
 725                 else
 726                         user_list = SMB_STRDUP("");
 727
 728                 if (!user_list)
 729                         return(False);
 730
 731                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 732                      !ok && auser;
 733                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 734                         fstring user2;
 735                         fstrcpy(user2,auser);
 736                         if (!user_ok(user2,snum))
 737                                 continue;
 738
 739                         if (password_ok(user2,password)) {
 740                                 ok = True;
 741                                 fstrcpy(user,user2);
 742                                 DEBUG(3,("authorise_login: ACCEPTED: session "
 743                                          "list username (%s) and given "
 744                                          "password ok\n", user));
 745                         }
 746                 }
 747
 748                 SAFE_FREE(user_list);
 749         }
 750
 751         /* check the user= fields and the given password */
 752         if (!ok && lp_username(snum)) {
 753                 TALLOC_CTX *ctx = talloc_tos();
 754                 char *auser;
 755                 char *user_list = talloc_strdup(ctx, lp_username(snum));
 756                 char *saveptr;
 757
 758                 if (!user_list) {
 759                         goto check_guest;
 760                 }
 761
 762                 user_list = talloc_string_sub(ctx,
 763                                 user_list,
 764                                 "%S",
 765                                 lp_servicename(snum));
 766
 767                 if (!user_list) {
 768                         goto check_guest;
 769                 }
 770
 771                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 772                      auser && !ok;
 773                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 774                         if (*auser == '@') {
 775                                 auser = validate_group(auser+1,password,snum);
 776                                 if (auser) {
 777                                         ok = True;
 778                                         fstrcpy(user,auser);
 779                                         DEBUG(3,("authorise_login: ACCEPTED: "
 780                                                  "group username and given "
 781                                                  "password ok (%s)\n", user));
 782                                 }
 783                         } else {
 784                                 fstring user2;
 785                                 fstrcpy(user2,auser);
 786                                 if (user_ok(user2,snum) &&
 787                                     password_ok(user2,password)) {
 788                                         ok = True;
 789                                         fstrcpy(user,user2);
 790                                         DEBUG(3,("authorise_login: ACCEPTED: "
 791                                                  "user list username and "
 792                                                  "given password ok (%s)\n",
 793                                                  user));
 794                                 }
 795                         }
 796                 }
 797         }
 798
 799   check_guest:
 800
 801         /* check for a normal guest connection */
 802         if (!ok && GUEST_OK(snum)) {
 803                 struct passwd *guest_pw;
 804                 fstring guestname;
 805                 fstrcpy(guestname,lp_guestaccount());
 806                 guest_pw = Get_Pwnam_alloc(talloc_tos(), guestname);
 807                 if (guest_pw != NULL) {
 808                         fstrcpy(user,guestname);
 809                         ok = True;
 810                         DEBUG(3,("authorise_login: ACCEPTED: guest account "
 811                                  "and guest ok (%s)\n", user));
 812                 } else {
 813                         DEBUG(0,("authorise_login: Invalid guest account "
 814                                  "%s??\n",guestname));
 815                 }
 816                 TALLOC_FREE(guest_pw);
 817                 *guest = True;
 818         }
 819
 820         if (ok && !user_ok(user, snum)) {
 821                 DEBUG(0,("authorise_login: rejected invalid user %s\n",user));
 822                 ok = False;
 823         }
 824
 825         return(ok);
 826 }