source/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 uint16_t 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         user_struct *usp, *next=NULL;
 143
 144         for (usp=validated_users;usp;usp=next) {
 145                 next = usp->next;
 146                 invalidate_vuid(usp->vuid);
 147         }
 148 }
 149
 150 static void increment_next_vuid(uint16_t *vuid)
 151 {
 152         *vuid += 1;
 153
 154         /* Check for vuid wrap. */
 155         if (*vuid == UID_FIELD_INVALID) {
 156                 *vuid = VUID_OFFSET;
 157         }
 158 }
 159
 160 /****************************************************
 161  Create a new partial auth user struct.
 162 *****************************************************/
 163
 164 int register_initial_vuid(void)
 165 {
 166         user_struct *vuser;
 167
 168         /* Paranoia check. */
 169         if(lp_security() == SEC_SHARE) {
 170                 smb_panic("register_initial_vuid: "
 171                         "Tried to register uid in security=share");
 172         }
 173
 174         /* Limit allowed vuids to 16bits - VUID_OFFSET. */
 175         if (num_validated_vuids >= 0xFFFF-VUID_OFFSET) {
 176                 return UID_FIELD_INVALID;
 177         }
 178
 179         if((vuser = talloc_zero(NULL, user_struct)) == NULL) {
 180                 DEBUG(0,("register_initial_vuid: "
 181                                 "Failed to talloc users struct!\n"));
 182                 return UID_FIELD_INVALID;
 183         }
 184
 185         /* Allocate a free vuid. Yes this is a linear search... */
 186         while( get_valid_user_struct_internal(next_vuid,
 187                         SERVER_ALLOCATED_REQUIRED_ANY) != NULL ) {
 188                 increment_next_vuid(&next_vuid);
 189         }
 190
 191         DEBUG(10,("register_initial_vuid: allocated vuid = %u\n",
 192                 (unsigned int)next_vuid ));
 193
 194         vuser->vuid = next_vuid;
 195
 196         /*
 197          * This happens in an unfinished NTLMSSP session setup. We
 198          * need to allocate a vuid between the first and second calls
 199          * to NTLMSSP.
 200          */
 201         increment_next_vuid(&next_vuid);
 202         num_validated_vuids++;
 203
 204         DLIST_ADD(validated_users, vuser);
 205         return vuser->vuid;
 206 }
 207
 208 static int register_homes_share(const char *username)
 209 {
 210         int result;
 211         struct passwd *pwd;
 212
 213         result = lp_servicenumber(username);
 214         if (result != -1) {
 215                 DEBUG(3, ("Using static (or previously created) service for "
 216                           "user '%s'; path = '%s'\n", username,
 217                           lp_pathname(result)));
 218                 return result;
 219         }
 220
 221         pwd = getpwnam_alloc(talloc_tos(), username);
 222
 223         if ((pwd == NULL) || (pwd->pw_dir[0] == '\0')) {
 224                 DEBUG(3, ("No home directory defined for user '%s'\n",
 225                           username));
 226                 TALLOC_FREE(pwd);
 227                 return -1;
 228         }
 229
 230         DEBUG(3, ("Adding homes service for user '%s' using home directory: "
 231                   "'%s'\n", username, pwd->pw_dir));
 232
 233         result = add_home_service(username, username, pwd->pw_dir);
 234
 235         TALLOC_FREE(pwd);
 236         return result;
 237 }
 238
 239 /**
 240  *  register that a valid login has been performed, establish 'session'.
 241  *  @param server_info The token returned from the authentication process.
 242  *   (now 'owned' by register_existing_vuid)
 243  *
 244  *  @param session_key The User session key for the login session (now also
 245  *  'owned' by register_existing_vuid)
 246  *
 247  *  @param respose_blob The NT challenge-response, if available.  (May be
 248  *  freed after this call)
 249  *
 250  *  @param smb_name The untranslated name of the user
 251  *
 252  *  @return Newly allocated vuid, biased by an offset. (This allows us to
 253  *   tell random client vuid's (normally zero) from valid vuids.)
 254  *
 255  */
 256
 257 int register_existing_vuid(uint16 vuid,
 258                         auth_serversupplied_info *server_info,
 259                         DATA_BLOB response_blob,
 260                         const char *smb_name)
 261 {
 262         fstring tmp;
 263         user_struct *vuser;
 264
 265         vuser = get_partial_auth_user_struct(vuid);
 266         if (!vuser) {
 267                 goto fail;
 268         }
 269
 270         /* Use this to keep tabs on all our info from the authentication */
 271         vuser->server_info = talloc_move(vuser, &server_info);
 272
 273         /* This is a potentially untrusted username */
 274         alpha_strcpy(tmp, smb_name, ". _-$", sizeof(tmp));
 275
 276         vuser->server_info->sanitized_username = talloc_strdup(
 277                 vuser->server_info, tmp);
 278
 279         DEBUG(10,("register_existing_vuid: (%u,%u) %s %s %s guest=%d\n",
 280                   (unsigned int)vuser->server_info->utok.uid,
 281                   (unsigned int)vuser->server_info->utok.gid,
 282                   vuser->server_info->unix_name,
 283                   vuser->server_info->sanitized_username,
 284                   pdb_get_domain(vuser->server_info->sam_account),
 285                   vuser->server_info->guest ));
 286
 287         DEBUG(3, ("register_existing_vuid: User name: %s\t"
 288                   "Real name: %s\n", vuser->server_info->unix_name,
 289                   pdb_get_fullname(vuser->server_info->sam_account)));
 290
 291         if (!vuser->server_info->ptok) {
 292                 DEBUG(1, ("register_existing_vuid: server_info does not "
 293                         "contain a user_token - cannot continue\n"));
 294                 goto fail;
 295         }
 296
 297         DEBUG(3,("register_existing_vuid: UNIX uid %d is UNIX user %s, "
 298                 "and will be vuid %u\n", (int)vuser->server_info->utok.uid,
 299                  vuser->server_info->unix_name, vuser->vuid));
 300
 301         if (!session_claim(vuser)) {
 302                 DEBUG(1, ("register_existing_vuid: Failed to claim session "
 303                         "for vuid=%d\n",
 304                         vuser->vuid));
 305                 goto fail;
 306         }
 307
 308         /* Register a home dir service for this user if
 309         (a) This is not a guest connection,
 310         (b) we have a home directory defined
 311         (c) there s not an existing static share by that name
 312         If a share exists by this name (autoloaded or not) reuse it . */
 313
 314         vuser->homes_snum = -1;
 315
 316         if (!vuser->server_info->guest) {
 317                 vuser->homes_snum = register_homes_share(
 318                         vuser->server_info->unix_name);
 319         }
 320
 321         if (srv_is_signing_negotiated() && !vuser->server_info->guest &&
 322                         !srv_signing_started()) {
 323                 /* Try and turn on server signing on the first non-guest
 324                  * sessionsetup. */
 325                 srv_set_signing(vuser->server_info->user_session_key, response_blob);
 326         }
 327
 328         /* fill in the current_user_info struct */
 329         set_current_user_info(
 330                 vuser->server_info->sanitized_username,
 331                 vuser->server_info->unix_name,
 332                 pdb_get_fullname(vuser->server_info->sam_account),
 333                 pdb_get_domain(vuser->server_info->sam_account));
 334
 335         return vuser->vuid;
 336
 337   fail:
 338
 339         if (vuser) {
 340                 invalidate_vuid(vuid);
 341         }
 342         return UID_FIELD_INVALID;
 343 }
 344
 345 /****************************************************************************
 346  Add a name to the session users list.
 347 ****************************************************************************/
 348
 349 void add_session_user(const char *user)
 350 {
 351         struct passwd *pw;
 352         char *tmp;
 353
 354         pw = Get_Pwnam_alloc(talloc_tos(), user);
 355
 356         if (pw == NULL) {
 357                 return;
 358         }
 359
 360         if (session_userlist == NULL) {
 361                 session_userlist = SMB_STRDUP(pw->pw_name);
 362                 goto done;
 363         }
 364
 365         if (in_list(pw->pw_name,session_userlist,False) ) {
 366                 goto done;
 367         }
 368
 369         if (strlen(session_userlist) > 128 * 1024) {
 370                 DEBUG(3,("add_session_user: session userlist already "
 371                          "too large.\n"));
 372                 goto done;
 373         }
 374
 375         if (asprintf(&tmp, "%s %s", session_userlist, pw->pw_name) == -1) {
 376                 DEBUG(3, ("asprintf failed\n"));
 377                 goto done;
 378         }
 379
 380         SAFE_FREE(session_userlist);
 381         session_userlist = tmp;
 382  done:
 383         TALLOC_FREE(pw);
 384 }
 385
 386 /****************************************************************************
 387  In security=share mode we need to store the client workgroup, as that's
 388   what Vista uses for the NTLMv2 calculation.
 389 ****************************************************************************/
 390
 391 void add_session_workgroup(const char *workgroup)
 392 {
 393         if (session_workgroup) {
 394                 SAFE_FREE(session_workgroup);
 395         }
 396         session_workgroup = smb_xstrdup(workgroup);
 397 }
 398
 399 /****************************************************************************
 400  In security=share mode we need to return the client workgroup, as that's
 401   what Vista uses for the NTLMv2 calculation.
 402 ****************************************************************************/
 403
 404 const char *get_session_workgroup(void)
 405 {
 406         return session_workgroup;
 407 }
 408
 409 /****************************************************************************
 410  Check if a user is in a netgroup user list. If at first we don't succeed,
 411  try lower case.
 412 ****************************************************************************/
 413
 414 bool user_in_netgroup(const char *user, const char *ngname)
 415 {
 416 #ifdef HAVE_NETGROUP
 417         static char *mydomain = NULL;
 418         fstring lowercase_user;
 419
 420         if (mydomain == NULL)
 421                 yp_get_default_domain(&mydomain);
 422
 423         if(mydomain == NULL) {
 424                 DEBUG(5,("Unable to get default yp domain, "
 425                         "let's try without specifying it\n"));
 426         }
 427
 428         DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 429                 user, mydomain?mydomain:"(ANY)", ngname));
 430
 431         if (innetgr(ngname, NULL, user, mydomain)) {
 432                 DEBUG(5,("user_in_netgroup: Found\n"));
 433                 return (True);
 434         } else {
 435
 436                 /*
 437                  * Ok, innetgr is case sensitive. Try once more with lowercase
 438                  * just in case. Attempt to fix #703. JRA.
 439                  */
 440
 441                 fstrcpy(lowercase_user, user);
 442                 strlower_m(lowercase_user);
 443
 444                 DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 445                         lowercase_user, mydomain?mydomain:"(ANY)", ngname));
 446
 447                 if (innetgr(ngname, NULL, lowercase_user, mydomain)) {
 448                         DEBUG(5,("user_in_netgroup: Found\n"));
 449                         return (True);
 450                 }
 451         }
 452 #endif /* HAVE_NETGROUP */
 453         return False;
 454 }
 455
 456 /****************************************************************************
 457  Check if a user is in a user list - can check combinations of UNIX
 458  and netgroup lists.
 459 ****************************************************************************/
 460
 461 bool user_in_list(const char *user,const char **list)
 462 {
 463         if (!list || !*list)
 464                 return False;
 465
 466         DEBUG(10,("user_in_list: checking user %s in list\n", user));
 467
 468         while (*list) {
 469
 470                 DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
 471                           user, *list));
 472
 473                 /*
 474                  * Check raw username.
 475                  */
 476                 if (strequal(user, *list))
 477                         return(True);
 478
 479                 /*
 480                  * Now check to see if any combination
 481                  * of UNIX and netgroups has been specified.
 482                  */
 483
 484                 if(**list == '@') {
 485                         /*
 486                          * Old behaviour. Check netgroup list
 487                          * followed by UNIX list.
 488                          */
 489                         if(user_in_netgroup(user, *list +1))
 490                                 return True;
 491                         if(user_in_group(user, *list +1))
 492                                 return True;
 493                 } else if (**list == '+') {
 494
 495                         if((*(*list +1)) == '&') {
 496                                 /*
 497                                  * Search UNIX list followed by netgroup.
 498                                  */
 499                                 if(user_in_group(user, *list +2))
 500                                         return True;
 501                                 if(user_in_netgroup(user, *list +2))
 502                                         return True;
 503
 504                         } else {
 505
 506                                 /*
 507                                  * Just search UNIX list.
 508                                  */
 509
 510                                 if(user_in_group(user, *list +1))
 511                                         return True;
 512                         }
 513
 514                 } else if (**list == '&') {
 515
 516                         if(*(*list +1) == '+') {
 517                                 /*
 518                                  * Search netgroup list followed by UNIX list.
 519                                  */
 520                                 if(user_in_netgroup(user, *list +2))
 521                                         return True;
 522                                 if(user_in_group(user, *list +2))
 523                                         return True;
 524                         } else {
 525                                 /*
 526                                  * Just search netgroup list.
 527                                  */
 528                                 if(user_in_netgroup(user, *list +1))
 529                                         return True;
 530                         }
 531                 }
 532
 533                 list++;
 534         }
 535         return(False);
 536 }
 537
 538 /****************************************************************************
 539  Check if a username is valid.
 540 ****************************************************************************/
 541
 542 static bool user_ok(const char *user, int snum)
 543 {
 544         char **valid, **invalid;
 545         bool ret;
 546
 547         valid = invalid = NULL;
 548         ret = True;
 549
 550         if (lp_invalid_users(snum)) {
 551                 str_list_copy(talloc_tos(), &invalid, lp_invalid_users(snum));
 552                 if (invalid &&
 553                     str_list_substitute(invalid, "%S", lp_servicename(snum))) {
 554
 555                         /* This is used in sec=share only, so no current user
 556                          * around to pass to str_list_sub_basic() */
 557
 558                         if ( invalid && str_list_sub_basic(invalid, "", "") ) {
 559                                 ret = !user_in_list(user,
 560                                                     (const char **)invalid);
 561                         }
 562                 }
 563         }
 564         TALLOC_FREE(invalid);
 565
 566         if (ret && lp_valid_users(snum)) {
 567                 str_list_copy(talloc_tos(), &valid, lp_valid_users(snum));
 568                 if ( valid &&
 569                      str_list_substitute(valid, "%S", lp_servicename(snum)) ) {
 570
 571                         /* This is used in sec=share only, so no current user
 572                          * around to pass to str_list_sub_basic() */
 573
 574                         if ( valid && str_list_sub_basic(valid, "", "") ) {
 575                                 ret = user_in_list(user, (const char **)valid);
 576                         }
 577                 }
 578         }
 579         TALLOC_FREE(valid);
 580
 581         if (ret && lp_onlyuser(snum)) {
 582                 char **user_list = str_list_make(
 583                         talloc_tos(), lp_username(snum), NULL);
 584                 if (user_list &&
 585                     str_list_substitute(user_list, "%S",
 586                                         lp_servicename(snum))) {
 587                         ret = user_in_list(user, (const char **)user_list);
 588                 }
 589                 TALLOC_FREE(user_list);
 590         }
 591
 592         return(ret);
 593 }
 594
 595 /****************************************************************************
 596  Validate a group username entry. Return the username or NULL.
 597 ****************************************************************************/
 598
 599 static char *validate_group(char *group, DATA_BLOB password,int snum)
 600 {
 601 #ifdef HAVE_NETGROUP
 602         {
 603                 char *host, *user, *domain;
 604                 setnetgrent(group);
 605                 while (getnetgrent(&host, &user, &domain)) {
 606                         if (user) {
 607                                 if (user_ok(user, snum) &&
 608                                     password_ok(user,password)) {
 609                                         endnetgrent();
 610                                         return(user);
 611                                 }
 612                         }
 613                 }
 614                 endnetgrent();
 615         }
 616 #endif
 617
 618 #ifdef HAVE_GETGRENT
 619         {
 620                 struct group *gptr;
 621                 setgrent();
 622                 while ((gptr = (struct group *)getgrent())) {
 623                         if (strequal(gptr->gr_name,group))
 624                                 break;
 625                 }
 626
 627                 /*
 628                  * As user_ok can recurse doing a getgrent(), we must
 629                  * copy the member list onto the heap before
 630                  * use. Bug pointed out by leon@eatworms.swmed.edu.
 631                  */
 632
 633                 if (gptr) {
 634                         char *member_list = NULL;
 635                         size_t list_len = 0;
 636                         char *member;
 637                         int i;
 638
 639                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 640                                 list_len += strlen(gptr->gr_mem[i])+1;
 641                         }
 642                         list_len++;
 643
 644                         member_list = (char *)SMB_MALLOC(list_len);
 645                         if (!member_list) {
 646                                 endgrent();
 647                                 return NULL;
 648                         }
 649
 650                         *member_list = '\0';
 651                         member = member_list;
 652
 653                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 654                                 size_t member_len = strlen(gptr->gr_mem[i])+1;
 655
 656                                 DEBUG(10,("validate_group: = gr_mem = "
 657                                           "%s\n", gptr->gr_mem[i]));
 658
 659                                 safe_strcpy(member, gptr->gr_mem[i],
 660                                         list_len - (member-member_list));
 661                                 member += member_len;
 662                         }
 663
 664                         endgrent();
 665
 666                         member = member_list;
 667                         while (*member) {
 668                                 if (user_ok(member,snum) &&
 669                                     password_ok(member,password)) {
 670                                         char *name = talloc_strdup(talloc_tos(),
 671                                                                 member);
 672                                         SAFE_FREE(member_list);
 673                                         return name;
 674                                 }
 675
 676                                 DEBUG(10,("validate_group = member = %s\n",
 677                                           member));
 678
 679                                 member += strlen(member) + 1;
 680                         }
 681
 682                         SAFE_FREE(member_list);
 683                 } else {
 684                         endgrent();
 685                         return NULL;
 686                 }
 687         }
 688 #endif
 689         return(NULL);
 690 }
 691
 692 /****************************************************************************
 693  Check for authority to login to a service with a given username/password.
 694  Note this is *NOT* used when logging on using sessionsetup_and_X.
 695 ****************************************************************************/
 696
 697 bool authorise_login(int snum, fstring user, DATA_BLOB password,
 698                      bool *guest)
 699 {
 700         bool ok = False;
 701
 702 #ifdef DEBUG_PASSWORD
 703         DEBUG(100,("authorise_login: checking authorisation on "
 704                    "user=%s pass=%s\n", user,password.data));
 705 #endif
 706
 707         *guest = False;
 708
 709         /* there are several possibilities:
 710                 1) login as the given user with given password
 711                 2) login as a previously registered username with the given
 712                    password
 713                 3) login as a session list username with the given password
 714                 4) login as a previously validated user/password pair
 715                 5) login as the "user =" user with given password
 716                 6) login as the "user =" user with no password
 717                    (guest connection)
 718                 7) login as guest user with no password
 719
 720                 if the service is guest_only then steps 1 to 5 are skipped
 721         */
 722
 723         /* now check the list of session users */
 724         if (!ok) {
 725                 char *auser;
 726                 char *user_list = NULL;
 727                 char *saveptr;
 728
 729                 if ( session_userlist )
 730                         user_list = SMB_STRDUP(session_userlist);
 731                 else
 732                         user_list = SMB_STRDUP("");
 733
 734                 if (!user_list)
 735                         return(False);
 736
 737                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 738                      !ok && auser;
 739                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 740                         fstring user2;
 741                         fstrcpy(user2,auser);
 742                         if (!user_ok(user2,snum))
 743                                 continue;
 744
 745                         if (password_ok(user2,password)) {
 746                                 ok = True;
 747                                 fstrcpy(user,user2);
 748                                 DEBUG(3,("authorise_login: ACCEPTED: session "
 749                                          "list username (%s) and given "
 750                                          "password ok\n", user));
 751                         }
 752                 }
 753
 754                 SAFE_FREE(user_list);
 755         }
 756
 757         /* check the user= fields and the given password */
 758         if (!ok && lp_username(snum)) {
 759                 TALLOC_CTX *ctx = talloc_tos();
 760                 char *auser;
 761                 char *user_list = talloc_strdup(ctx, lp_username(snum));
 762                 char *saveptr;
 763
 764                 if (!user_list) {
 765                         goto check_guest;
 766                 }
 767
 768                 user_list = talloc_string_sub(ctx,
 769                                 user_list,
 770                                 "%S",
 771                                 lp_servicename(snum));
 772
 773                 if (!user_list) {
 774                         goto check_guest;
 775                 }
 776
 777                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 778                      auser && !ok;
 779                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 780                         if (*auser == '@') {
 781                                 auser = validate_group(auser+1,password,snum);
 782                                 if (auser) {
 783                                         ok = True;
 784                                         fstrcpy(user,auser);
 785                                         DEBUG(3,("authorise_login: ACCEPTED: "
 786                                                  "group username and given "
 787                                                  "password ok (%s)\n", user));
 788                                 }
 789                         } else {
 790                                 fstring user2;
 791                                 fstrcpy(user2,auser);
 792                                 if (user_ok(user2,snum) &&
 793                                     password_ok(user2,password)) {
 794                                         ok = True;
 795                                         fstrcpy(user,user2);
 796                                         DEBUG(3,("authorise_login: ACCEPTED: "
 797                                                  "user list username and "
 798                                                  "given password ok (%s)\n",
 799                                                  user));
 800                                 }
 801                         }
 802                 }
 803         }
 804
 805   check_guest:
 806
 807         /* check for a normal guest connection */
 808         if (!ok && GUEST_OK(snum)) {
 809                 struct passwd *guest_pw;
 810                 fstring guestname;
 811                 fstrcpy(guestname,lp_guestaccount());
 812                 guest_pw = Get_Pwnam_alloc(talloc_tos(), guestname);
 813                 if (guest_pw != NULL) {
 814                         fstrcpy(user,guestname);
 815                         ok = True;
 816                         DEBUG(3,("authorise_login: ACCEPTED: guest account "
 817                                  "and guest ok (%s)\n", user));
 818                 } else {
 819                         DEBUG(0,("authorise_login: Invalid guest account "
 820                                  "%s??\n",guestname));
 821                 }
 822                 TALLOC_FREE(guest_pw);
 823                 *guest = True;
 824         }
 825
 826         if (ok && !user_ok(user, snum)) {
 827                 DEBUG(0,("authorise_login: rejected invalid user %s\n",user));
 828                 ok = False;
 829         }
 830
 831         return(ok);
 832 }