source3/auth/token_util.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Authentication utility functions
   4  *  Copyright (C) Andrew Tridgell 1992-1998
   5  *  Copyright (C) Andrew Bartlett 2001
   6  *  Copyright (C) Jeremy Allison 2000-2001
   7  *  Copyright (C) Rafal Szczesniak 2002
   8  *  Copyright (C) Volker Lendecke 2006
   9  *  Copyright (C) Michael Adam 2007
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 3 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License
  22  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25 /* functions moved from auth/auth_util.c to minimize linker deps */
  26
  27 #include "includes.h"
  28
  29 /****************************************************************************
  30  Check for a SID in an NT_USER_TOKEN
  31 ****************************************************************************/
  32
  33 bool nt_token_check_sid ( const struct dom_sid *sid, const NT_USER_TOKEN *token )
  34 {
  35         int i;
  36
  37         if ( !sid || !token )
  38                 return False;
  39
  40         for ( i=0; i<token->num_sids; i++ ) {
  41                 if ( sid_equal( sid, &token->user_sids[i] ) )
  42                         return True;
  43         }
  44
  45         return False;
  46 }
  47
  48 bool nt_token_check_domain_rid( NT_USER_TOKEN *token, uint32 rid )
  49 {
  50         struct dom_sid domain_sid;
  51
  52         /* if we are a domain member, the get the domain SID, else for
  53            a DC or standalone server, use our own SID */
  54
  55         if ( lp_server_role() == ROLE_DOMAIN_MEMBER ) {
  56                 if ( !secrets_fetch_domain_sid( lp_workgroup(),
  57                                                 &domain_sid ) ) {
  58                         DEBUG(1,("nt_token_check_domain_rid: Cannot lookup "
  59                                  "SID for domain [%s]\n", lp_workgroup()));
  60                         return False;
  61                 }
  62         }
  63         else
  64                 sid_copy( &domain_sid, get_global_sam_sid() );
  65
  66         sid_append_rid( &domain_sid, rid );
  67
  68         return nt_token_check_sid( &domain_sid, token );\
  69 }
  70
  71 /******************************************************************************
  72  Create a token for the root user to be used internally by smbd.
  73  This is similar to running under the context of the LOCAL_SYSTEM account
  74  in Windows.  This is a read-only token.  Do not modify it or free() it.
  75  Create a copy if your need to change it.
  76 ******************************************************************************/
  77
  78 NT_USER_TOKEN *get_root_nt_token( void )
  79 {
  80         struct nt_user_token *token, *for_cache;
  81         struct dom_sid u_sid, g_sid;
  82         struct passwd *pw;
  83         void *cache_data;
  84
  85         cache_data = memcache_lookup_talloc(
  86                 NULL, SINGLETON_CACHE_TALLOC,
  87                 data_blob_string_const_null("root_nt_token"));
  88
  89         if (cache_data != NULL) {
  90                 return talloc_get_type_abort(
  91                         cache_data, struct nt_user_token);
  92         }
  93
  94         if ( !(pw = sys_getpwuid(0)) ) {
  95                 if ( !(pw = sys_getpwnam("root")) ) {
  96                         DEBUG(0,("get_root_nt_token: both sys_getpwuid(0) "
  97                                 "and sys_getpwnam(\"root\") failed!\n"));
  98                         return NULL;
  99                 }
 100         }
 101
 102         /* get the user and primary group SIDs; although the
 103            BUILTIN\Administrators SId is really the one that matters here */
 104
 105         uid_to_sid(&u_sid, pw->pw_uid);
 106         gid_to_sid(&g_sid, pw->pw_gid);
 107
 108         token = create_local_nt_token(talloc_autofree_context(), &u_sid, False,
 109                                       1, &global_sid_Builtin_Administrators);
 110
 111         token->privileges = se_disk_operators;
 112
 113         for_cache = token;
 114
 115         memcache_add_talloc(
 116                 NULL, SINGLETON_CACHE_TALLOC,
 117                 data_blob_string_const_null("root_nt_token"), &for_cache);
 118
 119         return token;
 120 }
 121
 122
 123 /*
 124  * Add alias SIDs from memberships within the partially created token SID list
 125  */
 126
 127 NTSTATUS add_aliases(const struct dom_sid *domain_sid,
 128                      struct nt_user_token *token)
 129 {
 130         uint32 *aliases;
 131         size_t i, num_aliases;
 132         NTSTATUS status;
 133         TALLOC_CTX *tmp_ctx;
 134
 135         if (!(tmp_ctx = talloc_init("add_aliases"))) {
 136                 return NT_STATUS_NO_MEMORY;
 137         }
 138
 139         aliases = NULL;
 140         num_aliases = 0;
 141
 142         status = pdb_enum_alias_memberships(tmp_ctx, domain_sid,
 143                                             token->user_sids,
 144                                             token->num_sids,
 145                                             &aliases, &num_aliases);
 146
 147         if (!NT_STATUS_IS_OK(status)) {
 148                 DEBUG(10, ("pdb_enum_alias_memberships failed: %s\n",
 149                            nt_errstr(status)));
 150                 goto done;
 151         }
 152
 153         for (i=0; i<num_aliases; i++) {
 154                 struct dom_sid alias_sid;
 155                 sid_compose(&alias_sid, domain_sid, aliases[i]);
 156                 status = add_sid_to_array_unique(token, &alias_sid,
 157                                                  &token->user_sids,
 158                                                  &token->num_sids);
 159                 if (!NT_STATUS_IS_OK(status)) {
 160                         DEBUG(0, ("add_sid_to_array failed\n"));
 161                         goto done;
 162                 }
 163         }
 164
 165 done:
 166         TALLOC_FREE(tmp_ctx);
 167         return NT_STATUS_OK;
 168 }
 169
 170 /*******************************************************************
 171 *******************************************************************/
 172
 173 static NTSTATUS add_builtin_administrators(struct nt_user_token *token,
 174                                            const struct dom_sid *dom_sid)
 175 {
 176         struct dom_sid domadm;
 177         NTSTATUS status;
 178
 179         /* nothing to do if we aren't in a domain */
 180
 181         if ( !(IS_DC || lp_server_role()==ROLE_DOMAIN_MEMBER) ) {
 182                 return NT_STATUS_OK;
 183         }
 184
 185         /* Find the Domain Admins SID */
 186
 187         if ( IS_DC ) {
 188                 sid_copy( &domadm, get_global_sam_sid() );
 189         } else {
 190                 sid_copy(&domadm, dom_sid);
 191         }
 192         sid_append_rid( &domadm, DOMAIN_RID_ADMINS );
 193
 194         /* Add Administrators if the user beloongs to Domain Admins */
 195
 196         if ( nt_token_check_sid( &domadm, token ) ) {
 197                 status = add_sid_to_array(token,
 198                                           &global_sid_Builtin_Administrators,
 199                                           &token->user_sids, &token->num_sids);
 200         if (!NT_STATUS_IS_OK(status)) {
 201                         return status;
 202                 }
 203         }
 204
 205         return NT_STATUS_OK;
 206 }
 207
 208 /**
 209  * Create the requested BUILTIN if it doesn't already exist.  This requires
 210  * winbindd to be running.
 211  *
 212  * @param[in] rid BUILTIN rid to create
 213  * @return Normal NTSTATUS return.
 214  */
 215 static NTSTATUS create_builtin(uint32 rid)
 216 {
 217         NTSTATUS status = NT_STATUS_OK;
 218         struct dom_sid sid;
 219         gid_t gid;
 220
 221         if (!sid_compose(&sid, &global_sid_Builtin, rid)) {
 222                 return NT_STATUS_NO_SUCH_ALIAS;
 223         }
 224
 225         if (!sid_to_gid(&sid, &gid)) {
 226                 if (!lp_winbind_nested_groups() || !winbind_ping()) {
 227                         return NT_STATUS_PROTOCOL_UNREACHABLE;
 228                 }
 229                 status = pdb_create_builtin_alias(rid);
 230         }
 231         return status;
 232 }
 233
 234 /**
 235  * Add sid as a member of builtin_sid.
 236  *
 237  * @param[in] builtin_sid       An existing builtin group.
 238  * @param[in] dom_sid           sid to add as a member of builtin_sid.
 239  * @return Normal NTSTATUS return
 240  */
 241 static NTSTATUS add_sid_to_builtin(const struct dom_sid *builtin_sid,
 242                                    const struct dom_sid *dom_sid)
 243 {
 244         NTSTATUS status = NT_STATUS_OK;
 245
 246         if (!dom_sid || !builtin_sid) {
 247                 return NT_STATUS_INVALID_PARAMETER;
 248         }
 249
 250         status = pdb_add_aliasmem(builtin_sid, dom_sid);
 251
 252         if (NT_STATUS_EQUAL(status, NT_STATUS_MEMBER_IN_ALIAS)) {
 253                 DEBUG(5, ("add_sid_to_builtin %s is already a member of %s\n",
 254                           sid_string_dbg(dom_sid),
 255                           sid_string_dbg(builtin_sid)));
 256                 return NT_STATUS_OK;
 257         }
 258
 259         if (!NT_STATUS_IS_OK(status)) {
 260                 DEBUG(4, ("add_sid_to_builtin %s could not be added to %s: "
 261                           "%s\n", sid_string_dbg(dom_sid),
 262                           sid_string_dbg(builtin_sid), nt_errstr(status)));
 263         }
 264         return status;
 265 }
 266
 267 /*******************************************************************
 268 *******************************************************************/
 269
 270 NTSTATUS create_builtin_users(const struct dom_sid *dom_sid)
 271 {
 272         NTSTATUS status;
 273         struct dom_sid dom_users;
 274
 275         status = create_builtin(BUILTIN_RID_USERS);
 276         if ( !NT_STATUS_IS_OK(status) ) {
 277                 DEBUG(5,("create_builtin_users: Failed to create Users\n"));
 278                 return status;
 279         }
 280
 281         /* add domain users */
 282         if ((IS_DC || (lp_server_role() == ROLE_DOMAIN_MEMBER))
 283                 && sid_compose(&dom_users, dom_sid, DOMAIN_RID_USERS))
 284         {
 285                 status = add_sid_to_builtin(&global_sid_Builtin_Users,
 286                                             &dom_users);
 287         }
 288
 289         return status;
 290 }
 291
 292 /*******************************************************************
 293 *******************************************************************/
 294
 295 NTSTATUS create_builtin_administrators(const struct dom_sid *dom_sid)
 296 {
 297         NTSTATUS status;
 298         struct dom_sid dom_admins, root_sid;
 299         fstring root_name;
 300         enum lsa_SidType type;
 301         TALLOC_CTX *ctx;
 302         bool ret;
 303
 304         status = create_builtin(BUILTIN_RID_ADMINISTRATORS);
 305         if ( !NT_STATUS_IS_OK(status) ) {
 306                 DEBUG(5,("create_builtin_administrators: Failed to create Administrators\n"));
 307                 return status;
 308         }
 309
 310         /* add domain admins */
 311         if ((IS_DC || (lp_server_role() == ROLE_DOMAIN_MEMBER))
 312                 && sid_compose(&dom_admins, dom_sid, DOMAIN_RID_ADMINS))
 313         {
 314                 status = add_sid_to_builtin(&global_sid_Builtin_Administrators,
 315                                             &dom_admins);
 316                 if (!NT_STATUS_IS_OK(status)) {
 317                         return status;
 318                 }
 319         }
 320
 321         /* add root */
 322         if ( (ctx = talloc_init("create_builtin_administrators")) == NULL ) {
 323                 return NT_STATUS_NO_MEMORY;
 324         }
 325         fstr_sprintf( root_name, "%s\\root", get_global_sam_name() );
 326         ret = lookup_name(ctx, root_name, LOOKUP_NAME_DOMAIN, NULL, NULL,
 327                           &root_sid, &type);
 328         TALLOC_FREE( ctx );
 329
 330         if ( ret ) {
 331                 status = add_sid_to_builtin(&global_sid_Builtin_Administrators,
 332                                             &root_sid);
 333         }
 334
 335         return status;
 336 }
 337
 338 static NTSTATUS finalize_local_nt_token(struct nt_user_token *result,
 339                                         bool is_guest);
 340
 341 NTSTATUS create_local_nt_token_from_info3(TALLOC_CTX *mem_ctx,
 342                                           bool is_guest,
 343                                           struct netr_SamInfo3 *info3,
 344                                           struct extra_auth_info *extra,
 345                                           struct nt_user_token **ntok)
 346 {
 347         struct nt_user_token *usrtok = NULL;
 348         NTSTATUS status;
 349         int i;
 350
 351         DEBUG(10, ("Create local NT token for %s\n",
 352                    info3->base.account_name.string));
 353
 354         usrtok = talloc_zero(mem_ctx, struct nt_user_token);
 355         if (!usrtok) {
 356                 DEBUG(0, ("talloc failed\n"));
 357                 return NT_STATUS_NO_MEMORY;
 358         }
 359
 360         /* Add the user and primary group sid FIRST */
 361         /* check if the user rid is the special "Domain Guests" rid.
 362          * If so pick the first sid for the extra sids instead as it
 363          * is a local fake account */
 364         usrtok->user_sids = talloc_array(usrtok, struct dom_sid, 2);
 365         if (!usrtok->user_sids) {
 366                 TALLOC_FREE(usrtok);
 367                 return NT_STATUS_NO_MEMORY;
 368         }
 369         usrtok->num_sids = 2;
 370
 371         /* USER SID */
 372         if (info3->base.rid == (uint32_t)(-1)) {
 373                 /* this is a signal the user was fake and generated,
 374                  * the actual SID we want to use is stored in the extra
 375                  * sids */
 376                 if (is_null_sid(&extra->user_sid)) {
 377                         /* we couldn't find the user sid, bail out */
 378                         DEBUG(3, ("Invalid user SID\n"));
 379                         TALLOC_FREE(usrtok);
 380                         return NT_STATUS_UNSUCCESSFUL;
 381                 }
 382                 sid_copy(&usrtok->user_sids[0], &extra->user_sid);
 383         } else {
 384                 sid_copy(&usrtok->user_sids[0], info3->base.domain_sid);
 385                 sid_append_rid(&usrtok->user_sids[0], info3->base.rid);
 386         }
 387
 388         /* GROUP SID */
 389         if (info3->base.primary_gid == (uint32_t)(-1)) {
 390                 /* this is a signal the user was fake and generated,
 391                  * the actual SID we want to use is stored in the extra
 392                  * sids */
 393                 if (is_null_sid(&extra->pgid_sid)) {
 394                         /* we couldn't find the user sid, bail out */
 395                         DEBUG(3, ("Invalid group SID\n"));
 396                         TALLOC_FREE(usrtok);
 397                         return NT_STATUS_UNSUCCESSFUL;
 398                 }
 399                 sid_copy(&usrtok->user_sids[1], &extra->pgid_sid);
 400         } else {
 401                 sid_copy(&usrtok->user_sids[1], info3->base.domain_sid);
 402                 sid_append_rid(&usrtok->user_sids[1],
 403                                 info3->base.primary_gid);
 404         }
 405
 406         /* Now the SIDs we got from authentication. These are the ones from
 407          * the info3 struct or from the pdb_enum_group_memberships, depending
 408          * on who authenticated the user.
 409          * Note that we start the for loop at "1" here, we already added the
 410          * first group sid as primary above. */
 411
 412         for (i = 0; i < info3->base.groups.count; i++) {
 413                 struct dom_sid tmp_sid;
 414
 415                 sid_copy(&tmp_sid, info3->base.domain_sid);
 416                 sid_append_rid(&tmp_sid, info3->base.groups.rids[i].rid);
 417
 418                 status = add_sid_to_array_unique(usrtok, &tmp_sid,
 419                                                  &usrtok->user_sids,
 420                                                  &usrtok->num_sids);
 421                 if (!NT_STATUS_IS_OK(status)) {
 422                         DEBUG(3, ("Failed to add SID to nt token\n"));
 423                         TALLOC_FREE(usrtok);
 424                         return status;
 425                 }
 426         }
 427
 428         /* now also add extra sids if they are not the special user/group
 429          * sids */
 430         for (i = 0; i < info3->sidcount; i++) {
 431                 status = add_sid_to_array_unique(usrtok,
 432                                                  info3->sids[i].sid,
 433                                                  &usrtok->user_sids,
 434                                                  &usrtok->num_sids);
 435                 if (!NT_STATUS_IS_OK(status)) {
 436                         DEBUG(3, ("Failed to add SID to nt token\n"));
 437                         TALLOC_FREE(usrtok);
 438                         return status;
 439                 }
 440         }
 441
 442         status = finalize_local_nt_token(usrtok, is_guest);
 443         if (!NT_STATUS_IS_OK(status)) {
 444                 DEBUG(3, ("Failed to finalize nt token\n"));
 445                 TALLOC_FREE(usrtok);
 446                 return status;
 447         }
 448
 449         *ntok = usrtok;
 450         return NT_STATUS_OK;
 451 }
 452
 453 /*******************************************************************
 454  Create a NT token for the user, expanding local aliases
 455 *******************************************************************/
 456
 457 struct nt_user_token *create_local_nt_token(TALLOC_CTX *mem_ctx,
 458                                             const struct dom_sid *user_sid,
 459                                             bool is_guest,
 460                                             int num_groupsids,
 461                                             const struct dom_sid *groupsids)
 462 {
 463         struct nt_user_token *result = NULL;
 464         int i;
 465         NTSTATUS status;
 466
 467         DEBUG(10, ("Create local NT token for %s\n",
 468                    sid_string_dbg(user_sid)));
 469
 470         if (!(result = TALLOC_ZERO_P(mem_ctx, struct nt_user_token))) {
 471                 DEBUG(0, ("talloc failed\n"));
 472                 return NULL;
 473         }
 474
 475         /* Add the user and primary group sid */
 476
 477         status = add_sid_to_array(result, user_sid,
 478                                   &result->user_sids, &result->num_sids);
 479         if (!NT_STATUS_IS_OK(status)) {
 480                 TALLOC_FREE(result);
 481                 return NULL;
 482         }
 483
 484         /* For guest, num_groupsids may be zero. */
 485         if (num_groupsids) {
 486                 status = add_sid_to_array(result, &groupsids[0],
 487                                           &result->user_sids,
 488                                           &result->num_sids);
 489                 if (!NT_STATUS_IS_OK(status)) {
 490                         TALLOC_FREE(result);
 491                         return NULL;
 492                 }
 493         }
 494
 495         /* Now the SIDs we got from authentication. These are the ones from
 496          * the info3 struct or from the pdb_enum_group_memberships, depending
 497          * on who authenticated the user.
 498          * Note that we start the for loop at "1" here, we already added the
 499          * first group sid as primary above. */
 500
 501         for (i=1; i<num_groupsids; i++) {
 502                 status = add_sid_to_array_unique(result, &groupsids[i],
 503                                                  &result->user_sids,
 504                                                  &result->num_sids);
 505                 if (!NT_STATUS_IS_OK(status)) {
 506                         TALLOC_FREE(result);
 507                         return NULL;
 508                 }
 509         }
 510
 511         status = finalize_local_nt_token(result, is_guest);
 512         if (!NT_STATUS_IS_OK(status)) {
 513                 TALLOC_FREE(result);
 514                 return NULL;
 515         }
 516
 517         return result;
 518 }
 519
 520 static NTSTATUS finalize_local_nt_token(struct nt_user_token *result,
 521                                         bool is_guest)
 522 {
 523         struct dom_sid dom_sid;
 524         gid_t gid;
 525         NTSTATUS status;
 526
 527         /* Add in BUILTIN sids */
 528
 529         status = add_sid_to_array(result, &global_sid_World,
 530                                   &result->user_sids, &result->num_sids);
 531         if (!NT_STATUS_IS_OK(status)) {
 532                 return status;
 533         }
 534         status = add_sid_to_array(result, &global_sid_Network,
 535                                   &result->user_sids, &result->num_sids);
 536         if (!NT_STATUS_IS_OK(status)) {
 537                 return status;
 538         }
 539
 540         if (is_guest) {
 541                 status = add_sid_to_array(result, &global_sid_Builtin_Guests,
 542                                           &result->user_sids,
 543                                           &result->num_sids);
 544                 if (!NT_STATUS_IS_OK(status)) {
 545                         return status;
 546                 }
 547         } else {
 548                 status = add_sid_to_array(result,
 549                                           &global_sid_Authenticated_Users,
 550                                           &result->user_sids,
 551                                           &result->num_sids);
 552                 if (!NT_STATUS_IS_OK(status)) {
 553                         return status;
 554                 }
 555         }
 556
 557         /* Deal with the BUILTIN\Administrators group.  If the SID can
 558            be resolved then assume that the add_aliasmem( S-1-5-32 )
 559            handled it. */
 560
 561         if (!sid_to_gid(&global_sid_Builtin_Administrators, &gid)) {
 562
 563                 become_root();
 564                 if (!secrets_fetch_domain_sid(lp_workgroup(), &dom_sid)) {
 565                         status = NT_STATUS_OK;
 566                         DEBUG(3, ("Failed to fetch domain sid for %s\n",
 567                                   lp_workgroup()));
 568                 } else {
 569                         status = create_builtin_administrators(&dom_sid);
 570                 }
 571                 unbecome_root();
 572
 573                 if (NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE)) {
 574                         /* Add BUILTIN\Administrators directly to token. */
 575                         status = add_builtin_administrators(result, &dom_sid);
 576                         if ( !NT_STATUS_IS_OK(status) ) {
 577                                 DEBUG(3, ("Failed to check for local "
 578                                           "Administrators membership (%s)\n",
 579                                           nt_errstr(status)));
 580                         }
 581                 } else if (!NT_STATUS_IS_OK(status)) {
 582                         DEBUG(2, ("WARNING: Failed to create "
 583                                   "BUILTIN\\Administrators group!  Can "
 584                                   "Winbind allocate gids?\n"));
 585                 }
 586         }
 587
 588         /* Deal with the BUILTIN\Users group.  If the SID can
 589            be resolved then assume that the add_aliasmem( S-1-5-32 )
 590            handled it. */
 591
 592         if (!sid_to_gid(&global_sid_Builtin_Users, &gid)) {
 593
 594                 become_root();
 595                 if (!secrets_fetch_domain_sid(lp_workgroup(), &dom_sid)) {
 596                         status = NT_STATUS_OK;
 597                         DEBUG(3, ("Failed to fetch domain sid for %s\n",
 598                                   lp_workgroup()));
 599                 } else {
 600                         status = create_builtin_users(&dom_sid);
 601                 }
 602                 unbecome_root();
 603
 604                 if (!NT_STATUS_EQUAL(status, NT_STATUS_PROTOCOL_UNREACHABLE) &&
 605                     !NT_STATUS_IS_OK(status))
 606                 {
 607                         DEBUG(2, ("WARNING: Failed to create BUILTIN\\Users group! "
 608                                   "Can Winbind allocate gids?\n"));
 609                 }
 610         }
 611
 612         /* Deal with local groups */
 613
 614         if (lp_winbind_nested_groups()) {
 615
 616                 become_root();
 617
 618                 /* Now add the aliases. First the one from our local SAM */
 619
 620                 status = add_aliases(get_global_sam_sid(), result);
 621
 622                 if (!NT_STATUS_IS_OK(status)) {
 623                         unbecome_root();
 624                         return status;
 625                 }
 626
 627                 /* Finally the builtin ones */
 628
 629                 status = add_aliases(&global_sid_Builtin, result);
 630
 631                 if (!NT_STATUS_IS_OK(status)) {
 632                         unbecome_root();
 633                         return status;
 634                 }
 635
 636                 unbecome_root();
 637         }
 638
 639         /* Add privileges based on current user sids */
 640
 641         get_privileges_for_sids(&result->privileges, result->user_sids,
 642                                 result->num_sids);
 643
 644         return NT_STATUS_OK;
 645 }
 646
 647 /****************************************************************************
 648  prints a NT_USER_TOKEN to debug output.
 649 ****************************************************************************/
 650
 651 void debug_nt_user_token(int dbg_class, int dbg_lev, NT_USER_TOKEN *token)
 652 {
 653         size_t     i;
 654
 655         if (!token) {
 656                 DEBUGC(dbg_class, dbg_lev, ("NT user token: (NULL)\n"));
 657                 return;
 658         }
 659
 660         DEBUGC(dbg_class, dbg_lev,
 661                ("NT user token of user %s\n",
 662                 sid_string_dbg(&token->user_sids[0]) ));
 663         DEBUGADDC(dbg_class, dbg_lev,
 664                   ("contains %lu SIDs\n", (unsigned long)token->num_sids));
 665         for (i = 0; i < token->num_sids; i++)
 666                 DEBUGADDC(dbg_class, dbg_lev,
 667                           ("SID[%3lu]: %s\n", (unsigned long)i,
 668                            sid_string_dbg(&token->user_sids[i])));
 669
 670         dump_se_priv( dbg_class, dbg_lev, &token->privileges );
 671 }
 672
 673 /****************************************************************************
 674  prints a UNIX 'token' to debug output.
 675 ****************************************************************************/
 676
 677 void debug_unix_user_token(int dbg_class, int dbg_lev, uid_t uid, gid_t gid,
 678                            int n_groups, gid_t *groups)
 679 {
 680         int     i;
 681         DEBUGC(dbg_class, dbg_lev,
 682                ("UNIX token of user %ld\n", (long int)uid));
 683
 684         DEBUGADDC(dbg_class, dbg_lev,
 685                   ("Primary group is %ld and contains %i supplementary "
 686                    "groups\n", (long int)gid, n_groups));
 687         for (i = 0; i < n_groups; i++)
 688                 DEBUGADDC(dbg_class, dbg_lev, ("Group[%3i]: %ld\n", i,
 689                         (long int)groups[i]));
 690 }
 691
 692 /*
 693  * Create an artificial NT token given just a username. (Initially intended
 694  * for force user)
 695  *
 696  * We go through lookup_name() to avoid problems we had with 'winbind use
 697  * default domain'.
 698  *
 699  * We have 3 cases:
 700  *
 701  * unmapped unix users: Go directly to nss to find the user's group.
 702  *
 703  * A passdb user: The list of groups is provided by pdb_enum_group_memberships.
 704  *
 705  * If the user is provided by winbind, the primary gid is set to "domain
 706  * users" of the user's domain. For an explanation why this is necessary, see
 707  * the thread starting at
 708  * http://lists.samba.org/archive/samba-technical/2006-January/044803.html.
 709  */
 710
 711 NTSTATUS create_token_from_username(TALLOC_CTX *mem_ctx, const char *username,
 712                                     bool is_guest,
 713                                     uid_t *uid, gid_t *gid,
 714                                     char **found_username,
 715                                     struct nt_user_token **token)
 716 {
 717         NTSTATUS result = NT_STATUS_NO_SUCH_USER;
 718         TALLOC_CTX *tmp_ctx = talloc_stackframe();
 719         struct dom_sid user_sid;
 720         enum lsa_SidType type;
 721         gid_t *gids;
 722         struct dom_sid *group_sids;
 723         struct dom_sid unix_group_sid;
 724         size_t num_group_sids;
 725         size_t num_gids;
 726         size_t i;
 727
 728         if (!lookup_name_smbconf(tmp_ctx, username, LOOKUP_NAME_ALL,
 729                          NULL, NULL, &user_sid, &type)) {
 730                 DEBUG(1, ("lookup_name_smbconf for %s failed\n", username));
 731                 goto done;
 732         }
 733
 734         if (type != SID_NAME_USER) {
 735                 DEBUG(1, ("%s is a %s, not a user\n", username,
 736                           sid_type_lookup(type)));
 737                 goto done;
 738         }
 739
 740         if (sid_check_is_in_our_domain(&user_sid)) {
 741                 bool ret;
 742
 743                 /* This is a passdb user, so ask passdb */
 744
 745                 struct samu *sam_acct = NULL;
 746
 747                 if ( !(sam_acct = samu_new( tmp_ctx )) ) {
 748                         result = NT_STATUS_NO_MEMORY;
 749                         goto done;
 750                 }
 751
 752                 become_root();
 753                 ret = pdb_getsampwsid(sam_acct, &user_sid);
 754                 unbecome_root();
 755
 756                 if (!ret) {
 757                         DEBUG(1, ("pdb_getsampwsid(%s) for user %s failed\n",
 758                                   sid_string_dbg(&user_sid), username));
 759                         DEBUGADD(1, ("Fall back to unix user %s\n", username));
 760                         goto unix_user;
 761                 }
 762
 763                 result = pdb_enum_group_memberships(tmp_ctx, sam_acct,
 764                                                     &group_sids, &gids,
 765                                                     &num_group_sids);
 766                 if (!NT_STATUS_IS_OK(result)) {
 767                         DEBUG(1, ("enum_group_memberships failed for %s (%s): "
 768                                   "%s\n", username, sid_string_dbg(&user_sid),
 769                                   nt_errstr(result)));
 770                         DEBUGADD(1, ("Fall back to unix user %s\n", username));
 771                         goto unix_user;
 772                 }
 773
 774                 /* see the smb_panic() in pdb_default_enum_group_memberships */
 775                 SMB_ASSERT(num_group_sids > 0);
 776
 777                 *gid = gids[0];
 778
 779                 /* Ensure we're returning the found_username on the right context. */
 780                 *found_username = talloc_strdup(mem_ctx,
 781                                                 pdb_get_username(sam_acct));
 782
 783                 /*
 784                  * If the SID from lookup_name() was the guest sid, passdb knows
 785                  * about the mapping of guest sid to lp_guestaccount()
 786                  * username and will return the unix_pw info for a guest
 787                  * user. Use it if it's there, else lookup the *uid details
 788                  * using getpwnam_alloc(). See bug #6291 for details. JRA.
 789                  */
 790
 791                 /* We must always assign the *uid. */
 792                 if (sam_acct->unix_pw == NULL) {
 793                         struct passwd *pwd = getpwnam_alloc(sam_acct, *found_username );
 794                         if (!pwd) {
 795                                 DEBUG(10, ("getpwnam_alloc failed for %s\n",
 796                                         *found_username));
 797                                 result = NT_STATUS_NO_SUCH_USER;
 798                                 goto done;
 799                         }
 800                         result = samu_set_unix(sam_acct, pwd );
 801                         if (!NT_STATUS_IS_OK(result)) {
 802                                 DEBUG(10, ("samu_set_unix failed for %s\n",
 803                                         *found_username));
 804                                 result = NT_STATUS_NO_SUCH_USER;
 805                                 goto done;
 806                         }
 807                 }
 808                 *uid = sam_acct->unix_pw->pw_uid;
 809
 810         } else  if (sid_check_is_in_unix_users(&user_sid)) {
 811
 812                 /* This is a unix user not in passdb. We need to ask nss
 813                  * directly, without consulting passdb */
 814
 815                 struct passwd *pass;
 816
 817                 /*
 818                  * This goto target is used as a fallback for the passdb
 819                  * case. The concrete bug report is when passdb gave us an
 820                  * unmapped gid.
 821                  */
 822
 823         unix_user:
 824
 825                 if (!sid_to_uid(&user_sid, uid)) {
 826                         DEBUG(1, ("unix_user case, sid_to_uid for %s (%s) failed\n",
 827                                   username, sid_string_dbg(&user_sid)));
 828                         result = NT_STATUS_NO_SUCH_USER;
 829                         goto done;
 830                 }
 831
 832                 uid_to_unix_users_sid(*uid, &user_sid);
 833
 834                 pass = getpwuid_alloc(tmp_ctx, *uid);
 835                 if (pass == NULL) {
 836                         DEBUG(1, ("getpwuid(%u) for user %s failed\n",
 837                                   (unsigned int)*uid, username));
 838                         goto done;
 839                 }
 840
 841                 if (!getgroups_unix_user(tmp_ctx, username, pass->pw_gid,
 842                                          &gids, &num_group_sids)) {
 843                         DEBUG(1, ("getgroups_unix_user for user %s failed\n",
 844                                   username));
 845                         goto done;
 846                 }
 847
 848                 if (num_group_sids) {
 849                         group_sids = TALLOC_ARRAY(tmp_ctx, struct dom_sid, num_group_sids);
 850                         if (group_sids == NULL) {
 851                                 DEBUG(1, ("TALLOC_ARRAY failed\n"));
 852                                 result = NT_STATUS_NO_MEMORY;
 853                                 goto done;
 854                         }
 855                 } else {
 856                         group_sids = NULL;
 857                 }
 858
 859                 for (i=0; i<num_group_sids; i++) {
 860                         gid_to_sid(&group_sids[i], gids[i]);
 861                 }
 862
 863                 /* In getgroups_unix_user we always set the primary gid */
 864                 SMB_ASSERT(num_group_sids > 0);
 865
 866                 *gid = gids[0];
 867
 868                 /* Ensure we're returning the found_username on the right context. */
 869                 *found_username = talloc_strdup(mem_ctx, pass->pw_name);
 870         } else {
 871
 872                 /* This user is from winbind, force the primary gid to the
 873                  * user's "domain users" group. Under certain circumstances
 874                  * (user comes from NT4), this might be a loss of
 875                  * information. But we can not rely on winbind getting the
 876                  * correct info. AD might prohibit winbind looking up that
 877                  * information. */
 878
 879                 uint32 dummy;
 880
 881                 /* We must always assign the *uid. */
 882                 if (!sid_to_uid(&user_sid, uid)) {
 883                         DEBUG(1, ("winbindd case, sid_to_uid for %s (%s) failed\n",
 884                                   username, sid_string_dbg(&user_sid)));
 885                         result = NT_STATUS_NO_SUCH_USER;
 886                         goto done;
 887                 }
 888
 889                 num_group_sids = 1;
 890                 group_sids = TALLOC_ARRAY(tmp_ctx, struct dom_sid, num_group_sids);
 891                 if (group_sids == NULL) {
 892                         DEBUG(1, ("TALLOC_ARRAY failed\n"));
 893                         result = NT_STATUS_NO_MEMORY;
 894                         goto done;
 895                 }
 896
 897                 sid_copy(&group_sids[0], &user_sid);
 898                 sid_split_rid(&group_sids[0], &dummy);
 899                 sid_append_rid(&group_sids[0], DOMAIN_RID_USERS);
 900
 901                 if (!sid_to_gid(&group_sids[0], gid)) {
 902                         DEBUG(1, ("sid_to_gid(%s) failed\n",
 903                                   sid_string_dbg(&group_sids[0])));
 904                         goto done;
 905                 }
 906
 907                 gids = gid;
 908
 909                 /* Ensure we're returning the found_username on the right context. */
 910                 *found_username = talloc_strdup(mem_ctx, username);
 911         }
 912
 913         /* Add the "Unix Group" SID for each gid to catch mapped groups
 914            and their Unix equivalent.  This is to solve the backwards
 915            compatibility problem of 'valid users = +ntadmin' where
 916            ntadmin has been paired with "Domain Admins" in the group
 917            mapping table.  Otherwise smb.conf would need to be changed
 918            to 'valid user = "Domain Admins"'.  --jerry */
 919
 920         num_gids = num_group_sids;
 921         for ( i=0; i<num_gids; i++ ) {
 922                 gid_t high, low;
 923
 924                 /* don't pickup anything managed by Winbind */
 925
 926                 if ( lp_idmap_gid(&low, &high) && (gids[i] >= low) && (gids[i] <= high) )
 927                         continue;
 928
 929                 if ( !gid_to_unix_groups_sid( gids[i], &unix_group_sid ) ) {
 930                         DEBUG(1,("create_token_from_username: Failed to create SID "
 931                                 "for gid %u!\n", (unsigned int)gids[i]));
 932                         continue;
 933                 }
 934                 result = add_sid_to_array_unique(tmp_ctx, &unix_group_sid,
 935                                                  &group_sids, &num_group_sids);
 936                 if (!NT_STATUS_IS_OK(result)) {
 937                         goto done;
 938                 }
 939         }
 940
 941         /* Ensure we're creating the nt_token on the right context. */
 942         *token = create_local_nt_token(mem_ctx, &user_sid,
 943                                        is_guest, num_group_sids, group_sids);
 944
 945         if ((*token == NULL) || (*found_username == NULL)) {
 946                 result = NT_STATUS_NO_MEMORY;
 947                 goto done;
 948         }
 949
 950         result = NT_STATUS_OK;
 951  done:
 952         TALLOC_FREE(tmp_ctx);
 953         return result;
 954 }
 955
 956 /***************************************************************************
 957  Build upon create_token_from_username:
 958
 959  Expensive helper function to figure out whether a user given its name is
 960  member of a particular group.
 961 ***************************************************************************/
 962
 963 bool user_in_group_sid(const char *username, const struct dom_sid *group_sid)
 964 {
 965         NTSTATUS status;
 966         uid_t uid;
 967         gid_t gid;
 968         char *found_username;
 969         struct nt_user_token *token;
 970         bool result;
 971         TALLOC_CTX *mem_ctx = talloc_stackframe();
 972
 973         status = create_token_from_username(mem_ctx, username, False,
 974                                             &uid, &gid, &found_username,
 975                                             &token);
 976
 977         if (!NT_STATUS_IS_OK(status)) {
 978                 DEBUG(10, ("could not create token for %s\n", username));
 979                 TALLOC_FREE(mem_ctx);
 980                 return False;
 981         }
 982
 983         result = nt_token_check_sid(group_sid, token);
 984
 985         TALLOC_FREE(mem_ctx);
 986         return result;
 987 }
 988
 989 bool user_in_group(const char *username, const char *groupname)
 990 {
 991         TALLOC_CTX *mem_ctx = talloc_stackframe();
 992         struct dom_sid group_sid;
 993         bool ret;
 994
 995         ret = lookup_name(mem_ctx, groupname, LOOKUP_NAME_ALL,
 996                           NULL, NULL, &group_sid, NULL);
 997         TALLOC_FREE(mem_ctx);
 998
 999         if (!ret) {
1000                 DEBUG(10, ("lookup_name for (%s) failed.\n", groupname));
1001                 return False;
1002         }
1003
1004         return user_in_group_sid(username, &group_sid);
1005 }
1006
1007 /* END */