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         if (!session_claim(vuser)) {
 329                 DEBUG(1, ("register_existing_vuid: Failed to claim session "
 330                         "for vuid=%d\n",
 331                         vuser->vuid));
 332                 goto fail;
 333         }
 334
 335         /* Register a home dir service for this user if
 336         (a) This is not a guest connection,
 337         (b) we have a home directory defined
 338         (c) there s not an existing static share by that name
 339         If a share exists by this name (autoloaded or not) reuse it . */
 340
 341         vuser->homes_snum = -1;
 342         if ( (!vuser->guest) && vuser->unix_homedir && *(vuser->unix_homedir)) {
 343                 int servicenumber = lp_servicenumber(vuser->user.unix_name);
 344                 if ( servicenumber == -1 ) {
 345                         DEBUG(3, ("Adding homes service for user '%s' using "
 346                                 "home directory: '%s'\n",
 347                                 vuser->user.unix_name, vuser->unix_homedir));
 348                         vuser->homes_snum =
 349                                 add_home_service(vuser->user.unix_name,
 350                                                 vuser->user.unix_name,
 351                                                 vuser->unix_homedir);
 352                 } else {
 353                         DEBUG(3, ("Using static (or previously created) "
 354                                 "service for user '%s'; path = '%s'\n",
 355                                 vuser->user.unix_name,
 356                                 lp_pathname(servicenumber) ));
 357                         vuser->homes_snum = servicenumber;
 358                 }
 359         }
 360
 361         if (srv_is_signing_negotiated() && !vuser->guest &&
 362                         !srv_signing_started()) {
 363                 /* Try and turn on server signing on the first non-guest
 364                  * sessionsetup. */
 365                 srv_set_signing(vuser->session_key, response_blob);
 366         }
 367
 368         /* fill in the current_user_info struct */
 369         set_current_user_info( &vuser->user );
 370         return vuser->vuid;
 371
 372   fail:
 373
 374         if (vuser) {
 375                 invalidate_vuid(vuid);
 376         }
 377         return UID_FIELD_INVALID;
 378 }
 379
 380 /****************************************************************************
 381  Add a name to the session users list.
 382 ****************************************************************************/
 383
 384 void add_session_user(const char *user)
 385 {
 386         struct passwd *pw;
 387         char *tmp;
 388
 389         pw = Get_Pwnam_alloc(talloc_tos(), user);
 390
 391         if (pw == NULL) {
 392                 return;
 393         }
 394
 395         if (session_userlist == NULL) {
 396                 session_userlist = SMB_STRDUP(pw->pw_name);
 397                 goto done;
 398         }
 399
 400         if (in_list(pw->pw_name,session_userlist,False) ) {
 401                 goto done;
 402         }
 403
 404         if (strlen(session_userlist) > 128 * 1024) {
 405                 DEBUG(3,("add_session_user: session userlist already "
 406                          "too large.\n"));
 407                 goto done;
 408         }
 409
 410         if (asprintf(&tmp, "%s %s", session_userlist, pw->pw_name) == -1) {
 411                 DEBUG(3, ("asprintf failed\n"));
 412                 goto done;
 413         }
 414
 415         SAFE_FREE(session_userlist);
 416         session_userlist = tmp;
 417  done:
 418         TALLOC_FREE(pw);
 419 }
 420
 421 /****************************************************************************
 422  In security=share mode we need to store the client workgroup, as that's
 423   what Vista uses for the NTLMv2 calculation.
 424 ****************************************************************************/
 425
 426 void add_session_workgroup(const char *workgroup)
 427 {
 428         if (session_workgroup) {
 429                 SAFE_FREE(session_workgroup);
 430         }
 431         session_workgroup = smb_xstrdup(workgroup);
 432 }
 433
 434 /****************************************************************************
 435  In security=share mode we need to return the client workgroup, as that's
 436   what Vista uses for the NTLMv2 calculation.
 437 ****************************************************************************/
 438
 439 const char *get_session_workgroup(void)
 440 {
 441         return session_workgroup;
 442 }
 443
 444 /****************************************************************************
 445  Check if a user is in a netgroup user list. If at first we don't succeed,
 446  try lower case.
 447 ****************************************************************************/
 448
 449 bool user_in_netgroup(const char *user, const char *ngname)
 450 {
 451 #ifdef HAVE_NETGROUP
 452         static char *mydomain = NULL;
 453         fstring lowercase_user;
 454
 455         if (mydomain == NULL)
 456                 yp_get_default_domain(&mydomain);
 457
 458         if(mydomain == NULL) {
 459                 DEBUG(5,("Unable to get default yp domain, "
 460                         "let's try without specifying it\n"));
 461         }
 462
 463         DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 464                 user, mydomain?mydomain:"(ANY)", ngname));
 465
 466         if (innetgr(ngname, NULL, user, mydomain)) {
 467                 DEBUG(5,("user_in_netgroup: Found\n"));
 468                 return (True);
 469         } else {
 470
 471                 /*
 472                  * Ok, innetgr is case sensitive. Try once more with lowercase
 473                  * just in case. Attempt to fix #703. JRA.
 474                  */
 475
 476                 fstrcpy(lowercase_user, user);
 477                 strlower_m(lowercase_user);
 478
 479                 DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 480                         lowercase_user, mydomain?mydomain:"(ANY)", ngname));
 481
 482                 if (innetgr(ngname, NULL, lowercase_user, mydomain)) {
 483                         DEBUG(5,("user_in_netgroup: Found\n"));
 484                         return (True);
 485                 }
 486         }
 487 #endif /* HAVE_NETGROUP */
 488         return False;
 489 }
 490
 491 /****************************************************************************
 492  Check if a user is in a user list - can check combinations of UNIX
 493  and netgroup lists.
 494 ****************************************************************************/
 495
 496 bool user_in_list(const char *user,const char **list)
 497 {
 498         if (!list || !*list)
 499                 return False;
 500
 501         DEBUG(10,("user_in_list: checking user %s in list\n", user));
 502
 503         while (*list) {
 504
 505                 DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
 506                           user, *list));
 507
 508                 /*
 509                  * Check raw username.
 510                  */
 511                 if (strequal(user, *list))
 512                         return(True);
 513
 514                 /*
 515                  * Now check to see if any combination
 516                  * of UNIX and netgroups has been specified.
 517                  */
 518
 519                 if(**list == '@') {
 520                         /*
 521                          * Old behaviour. Check netgroup list
 522                          * followed by UNIX list.
 523                          */
 524                         if(user_in_netgroup(user, *list +1))
 525                                 return True;
 526                         if(user_in_group(user, *list +1))
 527                                 return True;
 528                 } else if (**list == '+') {
 529
 530                         if((*(*list +1)) == '&') {
 531                                 /*
 532                                  * Search UNIX list followed by netgroup.
 533                                  */
 534                                 if(user_in_group(user, *list +2))
 535                                         return True;
 536                                 if(user_in_netgroup(user, *list +2))
 537                                         return True;
 538
 539                         } else {
 540
 541                                 /*
 542                                  * Just search UNIX list.
 543                                  */
 544
 545                                 if(user_in_group(user, *list +1))
 546                                         return True;
 547                         }
 548
 549                 } else if (**list == '&') {
 550
 551                         if(*(*list +1) == '+') {
 552                                 /*
 553                                  * Search netgroup list followed by UNIX list.
 554                                  */
 555                                 if(user_in_netgroup(user, *list +2))
 556                                         return True;
 557                                 if(user_in_group(user, *list +2))
 558                                         return True;
 559                         } else {
 560                                 /*
 561                                  * Just search netgroup list.
 562                                  */
 563                                 if(user_in_netgroup(user, *list +1))
 564                                         return True;
 565                         }
 566                 }
 567
 568                 list++;
 569         }
 570         return(False);
 571 }
 572
 573 /****************************************************************************
 574  Check if a username is valid.
 575 ****************************************************************************/
 576
 577 static bool user_ok(const char *user, int snum)
 578 {
 579         char **valid, **invalid;
 580         bool ret;
 581
 582         valid = invalid = NULL;
 583         ret = True;
 584
 585         if (lp_invalid_users(snum)) {
 586                 str_list_copy(talloc_tos(), &invalid, lp_invalid_users(snum));
 587                 if (invalid &&
 588                     str_list_substitute(invalid, "%S", lp_servicename(snum))) {
 589
 590                         /* This is used in sec=share only, so no current user
 591                          * around to pass to str_list_sub_basic() */
 592
 593                         if ( invalid && str_list_sub_basic(invalid, "", "") ) {
 594                                 ret = !user_in_list(user,
 595                                                     (const char **)invalid);
 596                         }
 597                 }
 598         }
 599         TALLOC_FREE(invalid);
 600
 601         if (ret && lp_valid_users(snum)) {
 602                 str_list_copy(talloc_tos(), &valid, lp_valid_users(snum));
 603                 if ( valid &&
 604                      str_list_substitute(valid, "%S", lp_servicename(snum)) ) {
 605
 606                         /* This is used in sec=share only, so no current user
 607                          * around to pass to str_list_sub_basic() */
 608
 609                         if ( valid && str_list_sub_basic(valid, "", "") ) {
 610                                 ret = user_in_list(user, (const char **)valid);
 611                         }
 612                 }
 613         }
 614         TALLOC_FREE(valid);
 615
 616         if (ret && lp_onlyuser(snum)) {
 617                 char **user_list = str_list_make(
 618                         talloc_tos(), lp_username(snum), NULL);
 619                 if (user_list &&
 620                     str_list_substitute(user_list, "%S",
 621                                         lp_servicename(snum))) {
 622                         ret = user_in_list(user, (const char **)user_list);
 623                 }
 624                 TALLOC_FREE(user_list);
 625         }
 626
 627         return(ret);
 628 }
 629
 630 /****************************************************************************
 631  Validate a group username entry. Return the username or NULL.
 632 ****************************************************************************/
 633
 634 static char *validate_group(char *group, DATA_BLOB password,int snum)
 635 {
 636 #ifdef HAVE_NETGROUP
 637         {
 638                 char *host, *user, *domain;
 639                 setnetgrent(group);
 640                 while (getnetgrent(&host, &user, &domain)) {
 641                         if (user) {
 642                                 if (user_ok(user, snum) &&
 643                                     password_ok(user,password)) {
 644                                         endnetgrent();
 645                                         return(user);
 646                                 }
 647                         }
 648                 }
 649                 endnetgrent();
 650         }
 651 #endif
 652
 653 #ifdef HAVE_GETGRENT
 654         {
 655                 struct group *gptr;
 656                 setgrent();
 657                 while ((gptr = (struct group *)getgrent())) {
 658                         if (strequal(gptr->gr_name,group))
 659                                 break;
 660                 }
 661
 662                 /*
 663                  * As user_ok can recurse doing a getgrent(), we must
 664                  * copy the member list onto the heap before
 665                  * use. Bug pointed out by leon@eatworms.swmed.edu.
 666                  */
 667
 668                 if (gptr) {
 669                         char *member_list = NULL;
 670                         size_t list_len = 0;
 671                         char *member;
 672                         int i;
 673
 674                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 675                                 list_len += strlen(gptr->gr_mem[i])+1;
 676                         }
 677                         list_len++;
 678
 679                         member_list = (char *)SMB_MALLOC(list_len);
 680                         if (!member_list) {
 681                                 endgrent();
 682                                 return NULL;
 683                         }
 684
 685                         *member_list = '\0';
 686                         member = member_list;
 687
 688                         for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) {
 689                                 size_t member_len = strlen(gptr->gr_mem[i])+1;
 690
 691                                 DEBUG(10,("validate_group: = gr_mem = "
 692                                           "%s\n", gptr->gr_mem[i]));
 693
 694                                 safe_strcpy(member, gptr->gr_mem[i],
 695                                         list_len - (member-member_list));
 696                                 member += member_len;
 697                         }
 698
 699                         endgrent();
 700
 701                         member = member_list;
 702                         while (*member) {
 703                                 if (user_ok(member,snum) &&
 704                                     password_ok(member,password)) {
 705                                         char *name = talloc_strdup(talloc_tos(),
 706                                                                 member);
 707                                         SAFE_FREE(member_list);
 708                                         return name;
 709                                 }
 710
 711                                 DEBUG(10,("validate_group = member = %s\n",
 712                                           member));
 713
 714                                 member += strlen(member) + 1;
 715                         }
 716
 717                         SAFE_FREE(member_list);
 718                 } else {
 719                         endgrent();
 720                         return NULL;
 721                 }
 722         }
 723 #endif
 724         return(NULL);
 725 }
 726
 727 /****************************************************************************
 728  Check for authority to login to a service with a given username/password.
 729  Note this is *NOT* used when logging on using sessionsetup_and_X.
 730 ****************************************************************************/
 731
 732 bool authorise_login(int snum, fstring user, DATA_BLOB password,
 733                      bool *guest)
 734 {
 735         bool ok = False;
 736
 737 #ifdef DEBUG_PASSWORD
 738         DEBUG(100,("authorise_login: checking authorisation on "
 739                    "user=%s pass=%s\n", user,password.data));
 740 #endif
 741
 742         *guest = False;
 743
 744         /* there are several possibilities:
 745                 1) login as the given user with given password
 746                 2) login as a previously registered username with the given
 747                    password
 748                 3) login as a session list username with the given password
 749                 4) login as a previously validated user/password pair
 750                 5) login as the "user =" user with given password
 751                 6) login as the "user =" user with no password
 752                    (guest connection)
 753                 7) login as guest user with no password
 754
 755                 if the service is guest_only then steps 1 to 5 are skipped
 756         */
 757
 758         /* now check the list of session users */
 759         if (!ok) {
 760                 char *auser;
 761                 char *user_list = NULL;
 762                 char *saveptr;
 763
 764                 if ( session_userlist )
 765                         user_list = SMB_STRDUP(session_userlist);
 766                 else
 767                         user_list = SMB_STRDUP("");
 768
 769                 if (!user_list)
 770                         return(False);
 771
 772                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 773                      !ok && auser;
 774                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 775                         fstring user2;
 776                         fstrcpy(user2,auser);
 777                         if (!user_ok(user2,snum))
 778                                 continue;
 779
 780                         if (password_ok(user2,password)) {
 781                                 ok = True;
 782                                 fstrcpy(user,user2);
 783                                 DEBUG(3,("authorise_login: ACCEPTED: session "
 784                                          "list username (%s) and given "
 785                                          "password ok\n", user));
 786                         }
 787                 }
 788
 789                 SAFE_FREE(user_list);
 790         }
 791
 792         /* check the user= fields and the given password */
 793         if (!ok && lp_username(snum)) {
 794                 TALLOC_CTX *ctx = talloc_tos();
 795                 char *auser;
 796                 char *user_list = talloc_strdup(ctx, lp_username(snum));
 797                 char *saveptr;
 798
 799                 if (!user_list) {
 800                         goto check_guest;
 801                 }
 802
 803                 user_list = talloc_string_sub(ctx,
 804                                 user_list,
 805                                 "%S",
 806                                 lp_servicename(snum));
 807
 808                 if (!user_list) {
 809                         goto check_guest;
 810                 }
 811
 812                 for (auser = strtok_r(user_list, LIST_SEP, &saveptr);
 813                      auser && !ok;
 814                      auser = strtok_r(NULL, LIST_SEP, &saveptr)) {
 815                         if (*auser == '@') {
 816                                 auser = validate_group(auser+1,password,snum);
 817                                 if (auser) {
 818                                         ok = True;
 819                                         fstrcpy(user,auser);
 820                                         DEBUG(3,("authorise_login: ACCEPTED: "
 821                                                  "group username and given "
 822                                                  "password ok (%s)\n", user));
 823                                 }
 824                         } else {
 825                                 fstring user2;
 826                                 fstrcpy(user2,auser);
 827                                 if (user_ok(user2,snum) &&
 828                                     password_ok(user2,password)) {
 829                                         ok = True;
 830                                         fstrcpy(user,user2);
 831                                         DEBUG(3,("authorise_login: ACCEPTED: "
 832                                                  "user list username and "
 833                                                  "given password ok (%s)\n",
 834                                                  user));
 835                                 }
 836                         }
 837                 }
 838         }
 839
 840   check_guest:
 841
 842         /* check for a normal guest connection */
 843         if (!ok && GUEST_OK(snum)) {
 844                 struct passwd *guest_pw;
 845                 fstring guestname;
 846                 fstrcpy(guestname,lp_guestaccount());
 847                 guest_pw = Get_Pwnam_alloc(talloc_tos(), guestname);
 848                 if (guest_pw != NULL) {
 849                         fstrcpy(user,guestname);
 850                         ok = True;
 851                         DEBUG(3,("authorise_login: ACCEPTED: guest account "
 852                                  "and guest ok (%s)\n", user));
 853                 } else {
 854                         DEBUG(0,("authorise_login: Invalid guest account "
 855                                  "%s??\n",guestname));
 856                 }
 857                 TALLOC_FREE(guest_pw);
 858                 *guest = True;
 859         }
 860
 861         if (ok && !user_ok(user, snum)) {
 862                 DEBUG(0,("authorise_login: rejected invalid user %s\n",user));
 863                 ok = False;
 864         }
 865
 866         return(ok);
 867 }