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 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         data_blob_free(&vuser->session_key);
 123
 124         if (vuser->auth_ntlmssp_state) {
 125                 auth_ntlmssp_end(&vuser->auth_ntlmssp_state);
 126         }
 127
 128         DLIST_REMOVE(validated_users, vuser);
 129
 130         /* clear the vuid from the 'cache' on each connection, and
 131            from the vuid 'owner' of connections */
 132         conn_clear_vuid_cache(vuid);
 133
 134         TALLOC_FREE(vuser);
 135         num_validated_vuids--;
 136 }
 137
 138 /****************************************************************************
 139  Invalidate all vuid entries for this process.
 140 ****************************************************************************/
 141
 142 void invalidate_all_vuids(void)
 143 {
 144         user_struct *usp, *next=NULL;
 145
 146         for (usp=validated_users;usp;usp=next) {
 147                 next = usp->next;
 148                 invalidate_vuid(usp->vuid);
 149         }
 150 }
 151
 152 /****************************************************
 153  Create a new partial auth user struct.
 154 *****************************************************/
 155
 156 int register_initial_vuid(void)
 157 {
 158         user_struct *vuser;
 159
 160         /* Paranoia check. */
 161         if(lp_security() == SEC_SHARE) {
 162                 smb_panic("register_initial_vuid: "
 163                         "Tried to register uid in security=share");
 164         }
 165
 166         /* Limit allowed vuids to 16bits - VUID_OFFSET. */
 167         if (num_validated_vuids >= 0xFFFF-VUID_OFFSET) {
 168                 return UID_FIELD_INVALID;
 169         }
 170
 171         if((vuser = talloc_zero(NULL, user_struct)) == NULL) {
 172                 DEBUG(0,("register_initial_vuid: "
 173                                 "Failed to talloc users struct!\n"));
 174                 return UID_FIELD_INVALID;
 175         }
 176
 177         /* Allocate a free vuid. Yes this is a linear search... */
 178         while( get_valid_user_struct_internal(next_vuid,
 179                         SERVER_ALLOCATED_REQUIRED_ANY) != NULL ) {
 180                 next_vuid++;
 181                 /* Check for vuid wrap. */
 182                 if (next_vuid == UID_FIELD_INVALID) {
 183                         next_vuid = VUID_OFFSET;
 184                 }
 185         }
 186
 187         DEBUG(10,("register_initial_vuid: allocated vuid = %u\n",
 188                 (unsigned int)next_vuid ));
 189
 190         vuser->vuid = next_vuid;
 191
 192         /*
 193          * This happens in an unfinished NTLMSSP session setup. We
 194          * need to allocate a vuid between the first and second calls
 195          * to NTLMSSP.
 196          */
 197         next_vuid++;
 198         num_validated_vuids++;
 199
 200         DLIST_ADD(validated_users, vuser);
 201         return vuser->vuid;
 202 }
 203
 204 /**
 205  *  register that a valid login has been performed, establish 'session'.
 206  *  @param server_info The token returned from the authentication process.
 207  *   (now 'owned' by register_existing_vuid)
 208  *
 209  *  @param session_key The User session key for the login session (now also
 210  *  'owned' by register_existing_vuid)
 211  *
 212  *  @param respose_blob The NT challenge-response, if available.  (May be
 213  *  freed after this call)
 214  *
 215  *  @param smb_name The untranslated name of the user
 216  *
 217  *  @return Newly allocated vuid, biased by an offset. (This allows us to
 218  *   tell random client vuid's (normally zero) from valid vuids.)
 219  *
 220  */
 221
 222 int register_existing_vuid(uint16 vuid,
 223                         auth_serversupplied_info *server_info,
 224                         DATA_BLOB session_key,
 225                         DATA_BLOB response_blob,
 226                         const char *smb_name)
 227 {
 228         user_struct *vuser = get_partial_auth_user_struct(vuid);
 229         if (!vuser) {
 230                 goto fail;
 231         }
 232
 233         /* Use this to keep tabs on all our info from the authentication */
 234         vuser->server_info = server_info;
 235
 236         /* Ensure that the server_info will disappear with
 237          * the vuser it is now attached to */
 238
 239         talloc_steal(vuser, vuser->server_info);
 240
 241         /* the next functions should be done by a SID mapping system (SMS) as
 242          * the new real sam db won't have reference to unix uids or gids
 243          */
 244
 245         vuser->uid = server_info->uid;
 246         vuser->gid = server_info->gid;
 247
 248         vuser->n_groups = server_info->n_groups;
 249         if (vuser->n_groups) {
 250                 if (!(vuser->groups = (gid_t *)talloc_memdup(vuser,
 251                                         server_info->groups,
 252                                         sizeof(gid_t)*vuser->n_groups))) {
 253                         DEBUG(0,("register_existing_vuid: "
 254                                 "failed to talloc_memdup vuser->groups\n"));
 255                         goto fail;
 256                 }
 257         }
 258
 259         vuser->guest = server_info->guest;
 260         fstrcpy(vuser->user.unix_name, server_info->unix_name);
 261
 262         /* This is a potentially untrusted username */
 263         alpha_strcpy(vuser->user.smb_name, smb_name, ". _-$",
 264                 sizeof(vuser->user.smb_name));
 265
 266         fstrcpy(vuser->user.domain, pdb_get_domain(server_info->sam_account));
 267         fstrcpy(vuser->user.full_name,
 268         pdb_get_fullname(server_info->sam_account));
 269
 270         {
 271                 /* Keep the homedir handy */
 272                 const char *homedir =
 273                         pdb_get_homedir(server_info->sam_account);
 274                 const char *logon_script =
 275                         pdb_get_logon_script(server_info->sam_account);
 276
 277                 if (!IS_SAM_DEFAULT(server_info->sam_account,
 278                                         PDB_UNIXHOMEDIR)) {
 279                         const char *unix_homedir =
 280                                 pdb_get_unix_homedir(server_info->sam_account);
 281                         if (unix_homedir) {
 282                                 vuser->unix_homedir = unix_homedir;
 283                         }
 284                 } else {
 285                         struct passwd *passwd =
 286                                 getpwnam_alloc(vuser, vuser->user.unix_name);
 287                         if (passwd) {
 288                                 vuser->unix_homedir = passwd->pw_dir;
 289                                 /* Ensure that the unix_homedir now
 290                                  * belongs to vuser, so it goes away
 291                                  * with it, not with passwd below: */
 292                                 talloc_steal(vuser, vuser->unix_homedir);
 293                                 TALLOC_FREE(passwd);
 294                         }
 295                 }
 296
 297                 if (homedir) {
 298                         vuser->homedir = homedir;
 299                 }
 300                 if (logon_script) {
 301                         vuser->logon_script = logon_script;
 302                 }
 303         }
 304         vuser->session_key = session_key;
 305
 306         DEBUG(10,("register_existing_vuid: (%u,%u) %s %s %s guest=%d\n",
 307                         (unsigned int)vuser->uid,
 308                         (unsigned int)vuser->gid,
 309                         vuser->user.unix_name, vuser->user.smb_name,
 310                         vuser->user.domain, vuser->guest ));
 311
 312         DEBUG(3, ("register_existing_vuid: User name: %s\t"
 313                 "Real name: %s\n", vuser->user.unix_name,
 314                 vuser->user.full_name));
 315
 316         if (server_info->ptok) {
 317                 vuser->nt_user_token = dup_nt_token(vuser, server_info->ptok);
 318         } else {
 319                 DEBUG(1, ("register_existing_vuid: server_info does not "
 320                         "contain a user_token - cannot continue\n"));
 321                 goto fail;
 322         }
 323
 324         DEBUG(3,("register_existing_vuid: UNIX uid %d is UNIX user %s, "
 325                 "and will be vuid %u\n",
 326                 (int)vuser->uid,vuser->user.unix_name, vuser->vuid));
 327
 328         next_vuid++;
 329         num_validated_vuids++;
 330
 331         if (!session_claim(vuser)) {
 332                 DEBUG(1, ("register_existing_vuid: Failed to claim session "
 333                         "for vuid=%d\n",
 334                         vuser->vuid));
 335                 goto fail;
 336         }
 337
 338         /* Register a home dir service for this user if
 339         (a) This is not a guest connection,
 340         (b) we have a home directory defined
 341         (c) there s not an existing static share by that name
 342         If a share exists by this name (autoloaded or not) reuse it . */
 343
 344         vuser->homes_snum = -1;
 345         if ( (!vuser->guest) && vuser->unix_homedir && *(vuser->unix_homedir)) {
 346                 int servicenumber = lp_servicenumber(vuser->user.unix_name);
 347                 if ( servicenumber == -1 ) {
 348                         DEBUG(3, ("Adding homes service for user '%s' using "
 349                                 "home directory: '%s'\n",
 350                                 vuser->user.unix_name, vuser->unix_homedir));
 351                         vuser->homes_snum =
 352                                 add_home_service(vuser->user.unix_name,
 353                                                 vuser->user.unix_name,
 354                                                 vuser->unix_homedir);
 355                 } else {
 356                         DEBUG(3, ("Using static (or previously created) "
 357                                 "service for user '%s'; path = '%s'\n",
 358                                 vuser->user.unix_name,
 359                                 lp_pathname(servicenumber) ));
 360                         vuser->homes_snum = servicenumber;
 361                 }
 362         }
 363
 364         if (srv_is_signing_negotiated() && !vuser->guest &&
 365                         !srv_signing_started()) {
 366                 /* Try and turn on server signing on the first non-guest
 367                  * sessionsetup. */
 368                 srv_set_signing(vuser->session_key, response_blob);
 369         }
 370
 371         /* fill in the current_user_info struct */
 372         set_current_user_info( &vuser->user );
 373         return vuser->vuid;
 374
 375   fail:
 376
 377         if (vuser) {
 378                 invalidate_vuid(vuid);
 379         }
 380         return UID_FIELD_INVALID;
 381 }
 382
 383 /****************************************************************************
 384  Add a name to the session users list.
 385 ****************************************************************************/
 386
 387 void add_session_user(const char *user)
 388 {
 389         struct passwd *pw;
 390         char *tmp;
 391
 392         pw = Get_Pwnam_alloc(talloc_tos(), user);
 393
 394         if (pw == NULL) {
 395                 return;
 396         }
 397
 398         if (session_userlist == NULL) {
 399                 session_userlist = SMB_STRDUP(pw->pw_name);
 400                 goto done;
 401         }
 402
 403         if (in_list(pw->pw_name,session_userlist,False) ) {
 404                 goto done;
 405         }
 406
 407         if (strlen(session_userlist) > 128 * 1024) {
 408                 DEBUG(3,("add_session_user: session userlist already "
 409                          "too large.\n"));
 410                 goto done;
 411         }
 412
 413         if (asprintf(&tmp, "%s %s", session_userlist, pw->pw_name) == -1) {
 414                 DEBUG(3, ("asprintf failed\n"));
 415                 goto done;
 416         }
 417
 418         SAFE_FREE(session_userlist);
 419         session_userlist = tmp;
 420  done:
 421         TALLOC_FREE(pw);
 422 }
 423
 424 /****************************************************************************
 425  In security=share mode we need to store the client workgroup, as that's
 426   what Vista uses for the NTLMv2 calculation.
 427 ****************************************************************************/
 428
 429 void add_session_workgroup(const char *workgroup)
 430 {
 431         if (session_workgroup) {
 432                 SAFE_FREE(session_workgroup);
 433         }
 434         session_workgroup = smb_xstrdup(workgroup);
 435 }
 436
 437 /****************************************************************************
 438  In security=share mode we need to return the client workgroup, as that's
 439   what Vista uses for the NTLMv2 calculation.
 440 ****************************************************************************/
 441
 442 const char *get_session_workgroup(void)
 443 {
 444         return session_workgroup;
 445 }
 446
 447 /****************************************************************************
 448  Check if a user is in a netgroup user list. If at first we don't succeed,
 449  try lower case.
 450 ****************************************************************************/
 451
 452 bool user_in_netgroup(const char *user, const char *ngname)
 453 {
 454 #ifdef HAVE_NETGROUP
 455         static char *mydomain = NULL;
 456         fstring lowercase_user;
 457
 458         if (mydomain == NULL)
 459                 yp_get_default_domain(&mydomain);
 460
 461         if(mydomain == NULL) {
 462                 DEBUG(5,("Unable to get default yp domain, "
 463                         "let's try without specifying it\n"));
 464         }
 465
 466         DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 467                 user, mydomain?mydomain:"(ANY)", ngname));
 468
 469         if (innetgr(ngname, NULL, user, mydomain)) {
 470                 DEBUG(5,("user_in_netgroup: Found\n"));
 471                 return (True);
 472         } else {
 473
 474                 /*
 475                  * Ok, innetgr is case sensitive. Try once more with lowercase
 476                  * just in case. Attempt to fix #703. JRA.
 477                  */
 478
 479                 fstrcpy(lowercase_user, user);
 480                 strlower_m(lowercase_user);
 481
 482                 DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 483                         lowercase_user, mydomain?mydomain:"(ANY)", ngname));
 484
 485                 if (innetgr(ngname, NULL, lowercase_user, mydomain)) {
 486                         DEBUG(5,("user_in_netgroup: Found\n"));
 487                         return (True);
 488                 }
 489         }
 490 #endif /* HAVE_NETGROUP */
 491         return False;
 492 }
 493
 494 /****************************************************************************
 495  Check if a user is in a user list - can check combinations of UNIX
 496  and netgroup lists.
 497 ****************************************************************************/
 498
 499 bool user_in_list(const char *user,const char **list)
 500 {
 501         if (!list || !*list)
 502                 return False;
 503
 504         DEBUG(10,("user_in_list: checking user %s in list\n", user));
 505
 506         while (*list) {
 507
 508                 DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
 509                           user, *list));
 510
 511                 /*
 512                  * Check raw username.
 513                  */
 514                 if (strequal(user, *list))
 515                         return(True);
 516
 517                 /*
 518                  * Now check to see if any combination
 519                  * of UNIX and netgroups has been specified.
 520                  */
 521
 522                 if(**list == '@') {
 523                         /*
 524                          * Old behaviour. Check netgroup list
 525                          * followed by UNIX list.
 526                          */
 527                         if(user_in_netgroup(user, *list +1))
 528                                 return True;
 529                         if(user_in_group(user, *list +1))
 530                                 return True;
 531                 } else if (**list == '+') {
 532
 533                         if((*(*list +1)) == '&') {
 534                                 /*
 535                                  * Search UNIX list followed by netgroup.
 536                                  */
 537                                 if(user_in_group(user, *list +2))
 538                                         return True;
 539                                 if(user_in_netgroup(user, *list +2))
 540                                         return True;
 541
 542                         } else {
 543
 544                                 /*
 545                                  * Just search UNIX list.
 546                                  */
 547
 548                                 if(user_in_group(user, *list +1))
 549                                         return True;
 550                         }
 551
 552                 } else if (**list == '&') {
 553
 554                         if(*(*list +1) == '+') {
 555                                 /*
 556                                  * Search netgroup list followed by UNIX list.
 557                                  */
 558                                 if(user_in_netgroup(user, *list +2))
 559                                         return True;
 560                                 if(user_in_group(user, *list +2))
 561                                         return True;
 562                         } else {
 563                                 /*
 564                                  * Just search netgroup list.
 565                                  */
 566                                 if(user_in_netgroup(user, *list +1))
 567                                         return True;
 568                         }
 569                 }
 570
 571                 list++;
 572         }
 573         return(False);
 574 }
 575
 576 /****************************************************************************
 577  Check if a username is valid.
 578 ****************************************************************************/
 579
 580 static bool user_ok(const char *user, int snum)
 581 {
 582         char **valid, **invalid;
 583         bool ret;
 584
 585         valid = invalid = NULL;
 586         ret = True;
 587
 588         if (lp_invalid_users(snum)) {
 589                 str_list_copy(talloc_tos(), &invalid, lp_invalid_users(snum));
 590                 if (invalid &&
 591                     str_list_substitute(invalid, "%S", lp_servicename(snum))) {
 592
 593                         /* This is used in sec=share only, so no current user
 594                          * around to pass to str_list_sub_basic() */
 595
 596                         if ( invalid && str_list_sub_basic(invalid, "", "") ) {
 597                                 ret = !user_in_list(user,
 598                                                     (const char **)invalid);
 599                         }
 600                 }
 601         }
 602         TALLOC_FREE(invalid);
 603
 604         if (ret && lp_valid_users(snum)) {
 605                 str_list_copy(talloc_tos(), &valid, lp_valid_users(snum));
 606                 if ( valid &&
 607                      str_list_substitute(valid, "%S", lp_servicename(snum)) ) {
 608
 609                         /* This is used in sec=share only, so no current user
 610                          * around to pass to str_list_sub_basic() */
 611
 612                         if ( valid && str_list_sub_basic(valid, "", "") ) {
 613                                 ret = user_in_list(user, (const char **)valid);
 614                         }
 615                 }
 616         }
 617         TALLOC_FREE(valid);
 618
 619         if (ret && lp_onlyuser(snum)) {
 620                 char **user_list = str_list_make(
 621                         talloc_tos(), lp_username(snum), NULL);
 622                 if (user_list &&
 623                     str_list_substitute(user_list, "%S",
 624                                         lp_servicename(snum))) {
 625                         ret = user_in_list(user, (const char **)user_list);
 626                 }
 627                 TALLOC_FREE(user_list);
 628         }
 629
 630         return(ret);
 631 }
 632
 633 /****************************************************************************
 634  Validate a group username entry. Return the username or NULL.
 635 ****************************************************************************/
 636
 637 static char *validate_group(char *group, DATA_BLOB password,int snum)
 638 {
 639 #ifdef HAVE_NETGROUP
 640         {
 641                 char *host, *user, *domain;
 642                 setnetgrent(group);
 643                 while (getnetgrent(&host, &user, &domain)) {
 644                         if (user) {
 645                                 if (user_ok(user, snum) &&
 646                                     password_ok(user,password)) {
 647                                         endnetgrent();
 648                                         return(user);
 649                                 }
 650                         }
 651                 }
 652                 endnetgrent();
 653         }
 654 #endif
 655
 656 #ifdef HAVE_GETGRENT
 657         {
 658                 struct group *gptr;
 659                 setgrent();
 660                 while ((gptr = (struct group *)getgrent())) {
 661                         if (strequal(gptr->gr_name,group))
 662                                 break;
 663                 }
 664
 665                 /*
 666                  * As user_ok can recurse doing a getgrent(), we must
 667                  * copy the member list onto the heap before
 668                  * use. Bug pointed out by leon@eatworms.swmed.edu.
 669                  */
 670
 671                 if (gptr) {
 672                         char *member_list = NULL;
 673                         size_t list_len = 0;
 674                         char *member;
 675                         int i;
 676
 677                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 678                                 list_len += strlen(gptr->gr_mem[i])+1;
 679                         }
 680                         list_len++;
 681
 682                         member_list = (char *)SMB_MALLOC(list_len);
 683                         if (!member_list) {
 684                                 endgrent();
 685                                 return NULL;
 686                         }
 687
 688                         *member_list = '\0';
 689                         member = member_list;
 690
 691                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 692                                 size_t member_len = strlen(gptr->gr_mem[i])+1;
 693
 694                                 DEBUG(10,("validate_group: = gr_mem = "
 695                                           "%s\n", gptr->gr_mem[i]));
 696
 697                                 safe_strcpy(member, gptr->gr_mem[i],
 698                                         list_len - (member-member_list));
 699                                 member += member_len;
 700                         }
 701
 702                         endgrent();
 703
 704                         member = member_list;
 705                         while (*member) {
 706                                 if (user_ok(member,snum) &&
 707                                     password_ok(member,password)) {
 708                                         char *name = talloc_strdup(talloc_tos(),
 709                                                                 member);
 710                                         SAFE_FREE(member_list);
 711                                         return name;
 712                                 }
 713
 714                                 DEBUG(10,("validate_group = member = %s\n",
 715                                           member));
 716
 717                                 member += strlen(member) + 1;
 718                         }
 719
 720                         SAFE_FREE(member_list);
 721                 } else {
 722                         endgrent();
 723                         return NULL;
 724                 }
 725         }
 726 #endif
 727         return(NULL);
 728 }
 729
 730 /****************************************************************************
 731  Check for authority to login to a service with a given username/password.
 732  Note this is *NOT* used when logging on using sessionsetup_and_X.
 733 ****************************************************************************/
 734
 735 bool authorise_login(int snum, fstring user, DATA_BLOB password,
 736                      bool *guest)
 737 {
 738         bool ok = False;
 739
 740 #ifdef DEBUG_PASSWORD
 741         DEBUG(100,("authorise_login: checking authorisation on "
 742                    "user=%s pass=%s\n", user,password.data));
 743 #endif
 744
 745         *guest = False;
 746
 747         /* there are several possibilities:
 748                 1) login as the given user with given password
 749                 2) login as a previously registered username with the given
 750                    password
 751                 3) login as a session list username with the given password
 752                 4) login as a previously validated user/password pair
 753                 5) login as the "user =" user with given password
 754                 6) login as the "user =" user with no password
 755                    (guest connection)
 756                 7) login as guest user with no password
 757
 758                 if the service is guest_only then steps 1 to 5 are skipped
 759         */
 760
 761         /* now check the list of session users */
 762         if (!ok) {
 763                 char *auser;
 764                 char *user_list = NULL;
 765                 char *saveptr;
 766
 767                 if ( session_userlist )
 768                         user_list = SMB_STRDUP(session_userlist);
 769                 else
 770                         user_list = SMB_STRDUP("");
 771
 772                 if (!user_list)
 773                         return(False);
 774
 775                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 776                      !ok && auser;
 777                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 778                         fstring user2;
 779                         fstrcpy(user2,auser);
 780                         if (!user_ok(user2,snum))
 781                                 continue;
 782
 783                         if (password_ok(user2,password)) {
 784                                 ok = True;
 785                                 fstrcpy(user,user2);
 786                                 DEBUG(3,("authorise_login: ACCEPTED: session "
 787                                          "list username (%s) and given "
 788                                          "password ok\n", user));
 789                         }
 790                 }
 791
 792                 SAFE_FREE(user_list);
 793         }
 794
 795         /* check the user= fields and the given password */
 796         if (!ok && lp_username(snum)) {
 797                 TALLOC_CTX *ctx = talloc_tos();
 798                 char *auser;
 799                 char *user_list = talloc_strdup(ctx, lp_username(snum));
 800                 char *saveptr;
 801
 802                 if (!user_list) {
 803                         goto check_guest;
 804                 }
 805
 806                 user_list = talloc_string_sub(ctx,
 807                                 user_list,
 808                                 "%S",
 809                                 lp_servicename(snum));
 810
 811                 if (!user_list) {
 812                         goto check_guest;
 813                 }
 814
 815                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 816                      auser && !ok;
 817                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 818                         if (*auser == '@') {
 819                                 auser = validate_group(auser+1,password,snum);
 820                                 if (auser) {
 821                                         ok = True;
 822                                         fstrcpy(user,auser);
 823                                         DEBUG(3,("authorise_login: ACCEPTED: "
 824                                                  "group username and given "
 825                                                  "password ok (%s)\n", user));
 826                                 }
 827                         } else {
 828                                 fstring user2;
 829                                 fstrcpy(user2,auser);
 830                                 if (user_ok(user2,snum) &&
 831                                     password_ok(user2,password)) {
 832                                         ok = True;
 833                                         fstrcpy(user,user2);
 834                                         DEBUG(3,("authorise_login: ACCEPTED: "
 835                                                  "user list username and "
 836                                                  "given password ok (%s)\n",
 837                                                  user));
 838                                 }
 839                         }
 840                 }
 841         }
 842
 843   check_guest:
 844
 845         /* check for a normal guest connection */
 846         if (!ok && GUEST_OK(snum)) {
 847                 struct passwd *guest_pw;
 848                 fstring guestname;
 849                 fstrcpy(guestname,lp_guestaccount());
 850                 guest_pw = Get_Pwnam_alloc(talloc_tos(), guestname);
 851                 if (guest_pw != NULL) {
 852                         fstrcpy(user,guestname);
 853                         ok = True;
 854                         DEBUG(3,("authorise_login: ACCEPTED: guest account "
 855                                  "and guest ok (%s)\n", user));
 856                 } else {
 857                         DEBUG(0,("authorise_login: Invalid guest account "
 858                                  "%s??\n",guestname));
 859                 }
 860                 TALLOC_FREE(guest_pw);
 861                 *guest = True;
 862         }
 863
 864         if (ok && !user_ok(user, snum)) {
 865                 DEBUG(0,("authorise_login: rejected invalid user %s\n",user));
 866                 ok = False;
 867         }
 868
 869         return(ok);
 870 }