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