source/groupdb/mapping_ldb.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *
   4  *  group mapping code on top of ldb
   5  *
   6  *  Copyright (C) Andrew Tridgell              2006
   7  *
   8  * based on tdb group mapping code from groupdb/mapping.c
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or
  13  *  (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, write to the Free Software
  22  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25 #include "includes.h"
  26 #include "groupdb/mapping.h"
  27 #include "lib/ldb/include/includes.h"
  28 #include "lib/ldb/include/ldb_errors.h"
  29
  30 static struct ldb_context *ldb;
  31
  32 static BOOL mapping_upgrade(const char *tdb_path);
  33
  34 /*
  35   connect to the group mapping ldb
  36 */
  37  BOOL init_group_mapping(void)
  38 {
  39         BOOL existed;
  40         const char *init_ldif[] =
  41                 { "dn: @ATTRIBUTES\n" \
  42                   "ntName: CASE_INSENSITIVE\n" \
  43                   "\n",
  44                   "dn: @INDEXLIST\n" \
  45                   "@IDXATTR: gidNumber\n" \
  46                   "@IDXATTR: ntName\n" \
  47                   "@IDXATTR: member\n" };
  48         const char *db_path, *tdb_path;
  49         int ret;
  50         int flags = 0;
  51
  52         if (ldb != NULL) {
  53                 return True;
  54         }
  55
  56         /* this is needed as Samba3 doesn't have this globally yet */
  57         ldb_global_init();
  58
  59         db_path = lock_path("group_mapping.ldb");
  60
  61         ldb = ldb_init(NULL);
  62         if (ldb == NULL) goto failed;
  63
  64         existed = file_exist(db_path, NULL);
  65
  66         if (lp_parm_bool(-1, "groupmap", "nosync", False)) {
  67                 flags |= LDB_FLG_NOSYNC;
  68         }
  69
  70         ret = ldb_connect(ldb, db_path, flags, NULL);
  71         if (ret != LDB_SUCCESS) {
  72                 goto failed;
  73         }
  74
  75         if (!existed) {
  76                 /* initialise the ldb with an index */
  77                 struct ldb_ldif *ldif;
  78                 int i;
  79                 for (i=0;i<ARRAY_SIZE(init_ldif);i++) {
  80                         ldif = ldb_ldif_read_string(ldb, &init_ldif[i]);
  81                         if (ldif == NULL) goto failed;
  82                         ret = ldb_add(ldb, ldif->msg);
  83                         talloc_free(ldif);
  84                         if (ret == -1) goto failed;
  85                 }
  86         }
  87
  88         /* possibly upgrade */
  89         tdb_path = lock_path("group_mapping.tdb");
  90         if (file_exist(tdb_path, NULL) && !mapping_upgrade(tdb_path)) {
  91                 unlink(lock_path("group_mapping.ldb"));
  92                 goto failed;
  93         }
  94
  95         return True;
  96
  97 failed:
  98         DEBUG(0,("Failed to open group mapping ldb '%s' - '%s'\n",
  99                  db_path, ldb?ldb_errstring(ldb):strerror(errno)));
 100         talloc_free(ldb);
 101         ldb = NULL;
 102         return False;
 103 }
 104
 105
 106 /*
 107   form the DN for a mapping entry from a SID
 108  */
 109 static struct ldb_dn *mapping_dn(TALLOC_CTX *mem_ctx, const DOM_SID *sid)
 110 {
 111         fstring string_sid;
 112         uint32_t rid;
 113         DOM_SID domsid;
 114
 115         sid_copy(&domsid, sid);
 116         if (!sid_split_rid(&domsid, &rid)) {
 117                 return NULL;
 118         }
 119         if (!sid_to_string(string_sid, &domsid)) {
 120                 return NULL;
 121         }
 122         /* we split by domain and rid so we can do a subtree search
 123            when we only want one domain */
 124         return ldb_dn_string_compose(mem_ctx, NULL, "rid=%u,domain=%s",
 125                                      rid, string_sid);
 126 }
 127
 128 /*
 129   add a group mapping entry
 130  */
 131  BOOL add_mapping_entry(GROUP_MAP *map, int flag)
 132 {
 133         struct ldb_message *msg;
 134         int ret, i;
 135         fstring string_sid;
 136
 137         if (!init_group_mapping()) {
 138                 return False;
 139         }
 140
 141         msg = ldb_msg_new(ldb);
 142         if (msg == NULL) {
 143                 return False;
 144         }
 145
 146         msg->dn = mapping_dn(msg, &map->sid);
 147         if (msg->dn == NULL) {
 148                 goto failed;
 149         }
 150
 151         if (ldb_msg_add_string(msg, "objectClass", "groupMap") != LDB_SUCCESS ||
 152             ldb_msg_add_string(msg, "sid",
 153                                sid_to_string(string_sid, &map->sid)) != LDB_SUCCESS ||
 154             ldb_msg_add_fmt(msg, "gidNumber", "%u", (unsigned)map->gid) != LDB_SUCCESS ||
 155             ldb_msg_add_fmt(msg, "sidNameUse", "%u", (unsigned)map->sid_name_use) != LDB_SUCCESS ||
 156             ldb_msg_add_string(msg, "comment", map->comment) != LDB_SUCCESS ||
 157             ldb_msg_add_string(msg, "ntName", map->nt_name) != LDB_SUCCESS) {
 158                 goto failed;
 159         }
 160
 161         ret = ldb_add(ldb, msg);
 162
 163         /* if it exists we update it. This is a hangover from the semantics the
 164            tdb backend had */
 165         if (ret == LDB_ERR_ENTRY_ALREADY_EXISTS) {
 166                 for (i=0;i<msg->num_elements;i++) {
 167                         msg->elements[i].flags = LDB_FLAG_MOD_REPLACE;
 168                 }
 169                 ret = ldb_modify(ldb, msg);
 170         }
 171
 172         talloc_free(msg);
 173
 174         return ret == LDB_SUCCESS;
 175
 176 failed:
 177         talloc_free(msg);
 178         return False;
 179 }
 180
 181 /*
 182   unpack a ldb message into a GROUP_MAP structure
 183 */
 184 static BOOL msg_to_group_map(struct ldb_message *msg, GROUP_MAP *map)
 185 {
 186         const char *sidstr;
 187
 188         map->gid          = ldb_msg_find_attr_as_int(msg, "gidNumber", -1);
 189         map->sid_name_use = ldb_msg_find_attr_as_int(msg, "sidNameUse", -1);
 190         fstrcpy(map->nt_name, ldb_msg_find_attr_as_string(msg, "ntName", NULL));
 191         fstrcpy(map->comment, ldb_msg_find_attr_as_string(msg, "comment", NULL));
 192         sidstr = ldb_msg_find_attr_as_string(msg, "sid", NULL);
 193
 194         if (!string_to_sid(&map->sid, sidstr) ||
 195             map->gid == (gid_t)-1 ||
 196             map->sid_name_use == (enum lsa_SidType)-1) {
 197                 DEBUG(0,("Unable to unpack group mapping\n"));
 198                 return False;
 199         }
 200
 201         return True;
 202 }
 203
 204 /*
 205  return a group map entry for a given sid
 206 */
 207  BOOL get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
 208 {
 209         int ret;
 210         struct ldb_dn *dn;
 211         struct ldb_result *res=NULL;
 212
 213         if (!init_group_mapping()) {
 214                 return False;
 215         }
 216
 217         dn = mapping_dn(ldb, &sid);
 218         if (dn == NULL) goto failed;
 219
 220         ret = ldb_search(ldb, dn, LDB_SCOPE_BASE, NULL, NULL, &res);
 221         talloc_steal(dn, res);
 222         if (ret != LDB_SUCCESS || res->count != 1) {
 223                 goto failed;
 224         }
 225
 226         if (!msg_to_group_map(res->msgs[0], map)) goto failed;
 227
 228         talloc_free(dn);
 229         return True;
 230
 231 failed:
 232         talloc_free(dn);
 233         return False;
 234 }
 235
 236 /*
 237  return a group map entry for a given gid
 238 */
 239  BOOL get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
 240 {
 241         int ret;
 242         char *expr;
 243         struct ldb_result *res=NULL;
 244
 245         if (!init_group_mapping()) {
 246                 return False;
 247         }
 248
 249         expr = talloc_asprintf(ldb, "(&(gidNumber=%u)(objectClass=groupMap))",
 250                                (unsigned)gid);
 251         if (expr == NULL) goto failed;
 252
 253         ret = ldb_search(ldb, NULL, LDB_SCOPE_SUBTREE, expr, NULL, &res);
 254         talloc_steal(expr, res);
 255         if (ret != LDB_SUCCESS || res->count != 1) goto failed;
 256
 257         if (!msg_to_group_map(res->msgs[0], map)) goto failed;
 258
 259         talloc_free(expr);
 260         return True;
 261
 262 failed:
 263         talloc_free(expr);
 264         return False;
 265 }
 266
 267 /*
 268   Return the sid and the type of the unix group.
 269 */
 270  BOOL get_group_map_from_ntname(const char *name, GROUP_MAP *map)
 271 {
 272         int ret;
 273         char *expr;
 274         struct ldb_result *res=NULL;
 275
 276         if (!init_group_mapping()) {
 277                 return False;
 278         }
 279
 280         expr = talloc_asprintf(ldb, "(&(ntName=%s)(objectClass=groupMap))", name);
 281         if (expr == NULL) goto failed;
 282
 283         ret = ldb_search(ldb, NULL, LDB_SCOPE_SUBTREE, expr, NULL, &res);
 284         talloc_steal(expr, res);
 285         if (ret != LDB_SUCCESS || res->count != 1) goto failed;
 286
 287         if (!msg_to_group_map(res->msgs[0], map)) goto failed;
 288
 289         talloc_free(expr);
 290         return True;
 291
 292 failed:
 293         talloc_free(expr);
 294         return False;
 295 }
 296
 297 /*
 298  Remove a group mapping entry.
 299 */
 300  BOOL group_map_remove(const DOM_SID *sid)
 301 {
 302         struct ldb_dn *dn;
 303         int ret;
 304
 305         if (!init_group_mapping()) {
 306                 return False;
 307         }
 308
 309         dn = mapping_dn(ldb, sid);
 310         if (dn == NULL) {
 311                 return False;
 312         }
 313         ret = ldb_delete(ldb, dn);
 314         talloc_free(dn);
 315
 316         return ret == LDB_SUCCESS;
 317 }
 318
 319
 320 /*
 321   Enumerate the group mappings for a domain
 322 */
 323  BOOL enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use,
 324                          GROUP_MAP **pp_rmap,
 325                          size_t *p_num_entries, BOOL unix_only)
 326 {
 327         int i, ret;
 328         char *expr;
 329         fstring name;
 330         struct ldb_result *res;
 331         struct ldb_dn *basedn=NULL;
 332         TALLOC_CTX *tmp_ctx;
 333
 334         if (!init_group_mapping()) {
 335                 return False;
 336         }
 337
 338         tmp_ctx = talloc_new(ldb);
 339         if (tmp_ctx == NULL) goto failed;
 340
 341         if (sid_name_use == SID_NAME_UNKNOWN) {
 342                 expr = talloc_asprintf(tmp_ctx, "(&(objectClass=groupMap))");
 343         } else {
 344                 expr = talloc_asprintf(tmp_ctx, "(&(sidNameUse=%u)(objectClass=groupMap))",
 345                                        sid_name_use);
 346         }
 347         if (expr == NULL) goto failed;
 348
 349         /* we do a subtree search on the domain */
 350         if (domsid != NULL) {
 351                 sid_to_string(name, domsid);
 352                 basedn = ldb_dn_string_compose(tmp_ctx, NULL, "domain=%s", name);
 353                 if (basedn == NULL) goto failed;
 354         }
 355
 356         ret = ldb_search(ldb, basedn, LDB_SCOPE_SUBTREE, expr, NULL, &res);
 357         if (ret != LDB_SUCCESS) goto failed;
 358
 359         (*pp_rmap) = NULL;
 360         *p_num_entries = 0;
 361
 362         for (i=0;i<res->count;i++) {
 363                 (*pp_rmap) = SMB_REALLOC_ARRAY((*pp_rmap), GROUP_MAP,
 364                                                (*p_num_entries)+1);
 365                 if (!(*pp_rmap)) goto failed;
 366
 367                 if (!msg_to_group_map(res->msgs[i], &(*pp_rmap)[*p_num_entries])) {
 368                         goto failed;
 369                 }
 370
 371                 (*p_num_entries)++;
 372         }
 373
 374         talloc_free(tmp_ctx);
 375         return True;
 376
 377 failed:
 378         talloc_free(tmp_ctx);
 379         return False;
 380 }
 381
 382 /*
 383    This operation happens on session setup, so it should better be fast. We
 384    store a list of aliases a SID is member of hanging off MEMBEROF/SID.
 385 */
 386  NTSTATUS one_alias_membership(const DOM_SID *member,
 387                                DOM_SID **sids, size_t *num)
 388 {
 389         const char *attrs[] = {
 390                 "sid",
 391                 NULL
 392         };
 393         DOM_SID alias;
 394         char *expr;
 395         int ret, i;
 396         struct ldb_result *res=NULL;
 397         fstring string_sid;
 398         NTSTATUS status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 399
 400         if (!init_group_mapping()) {
 401                 return NT_STATUS_ACCESS_DENIED;
 402         }
 403
 404         if (!sid_to_string(string_sid, member)) {
 405                 return NT_STATUS_INVALID_PARAMETER;
 406         }
 407
 408         expr = talloc_asprintf(ldb, "(&(member=%s)(objectClass=groupMap))",
 409                                string_sid);
 410         if (expr == NULL) goto failed;
 411
 412         ret = ldb_search(ldb, NULL, LDB_SCOPE_SUBTREE, expr, attrs, &res);
 413         talloc_steal(expr, res);
 414         if (ret != LDB_SUCCESS) {
 415                 goto failed;
 416         }
 417
 418         for (i=0;i<res->count;i++) {
 419                 struct ldb_message_element *el;
 420                 el = ldb_msg_find_element(res->msgs[i], "sid");
 421                 if (el == NULL || el->num_values != 1) {
 422                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 423                         goto failed;
 424                 }
 425                 string_to_sid(&alias, (char *)el->values[0].data);
 426                 if (!add_sid_to_array_unique(NULL, &alias, sids, num)) {
 427                         status = NT_STATUS_NO_MEMORY;
 428                         goto failed;
 429                 }
 430         }
 431
 432         talloc_free(expr);
 433         return NT_STATUS_OK;
 434
 435 failed:
 436         talloc_free(expr);
 437         return status;
 438 }
 439
 440 /*
 441   add/remove a member field
 442 */
 443 static NTSTATUS modify_aliasmem(const DOM_SID *alias, const DOM_SID *member,
 444                                 int operation)
 445 {
 446         fstring string_sid;
 447         int ret;
 448         struct ldb_message msg;
 449         struct ldb_message_element el;
 450         struct ldb_val val;
 451         TALLOC_CTX *tmp_ctx;
 452         GROUP_MAP map;
 453
 454         if (!init_group_mapping()) {
 455                 return NT_STATUS_ACCESS_DENIED;
 456         }
 457
 458         if (!get_group_map_from_sid(*alias, &map)) {
 459                 sid_to_string(string_sid, alias);
 460                 return NT_STATUS_NO_SUCH_ALIAS;
 461         }
 462
 463         if ((map.sid_name_use != SID_NAME_ALIAS) &&
 464             (map.sid_name_use != SID_NAME_WKN_GRP)) {
 465                 DEBUG(0,("sid_name_use=%d\n", map.sid_name_use));
 466                 return NT_STATUS_NO_SUCH_ALIAS;
 467         }
 468
 469         tmp_ctx = talloc_new(NULL);
 470         if (tmp_ctx == NULL) {
 471                 return NT_STATUS_NO_MEMORY;
 472         }
 473
 474         msg.dn = mapping_dn(tmp_ctx, alias);
 475         if (msg.dn == NULL) {
 476                 return NT_STATUS_NO_MEMORY;
 477         }
 478         msg.num_elements = 1;
 479         msg.elements = &el;
 480         el.flags = operation;
 481         el.name = talloc_strdup(tmp_ctx, "member");
 482         el.num_values = 1;
 483         el.values = &val;
 484         sid_to_string(string_sid, member);
 485         val.data = (uint8_t *)string_sid;
 486         val.length = strlen(string_sid);
 487
 488         ret = ldb_modify(ldb, &msg);
 489         talloc_free(tmp_ctx);
 490
 491         if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 492                 return NT_STATUS_NO_SUCH_ALIAS;
 493         }
 494
 495         if (operation == LDB_FLAG_MOD_ADD &&
 496             ret == LDB_ERR_ATTRIBUTE_OR_VALUE_EXISTS) {
 497                 return NT_STATUS_MEMBER_IN_ALIAS;
 498         }
 499
 500         return (ret == LDB_SUCCESS ? NT_STATUS_OK : NT_STATUS_ACCESS_DENIED);
 501 }
 502
 503  NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 504 {
 505         return modify_aliasmem(alias, member, LDB_FLAG_MOD_ADD);
 506 }
 507
 508  NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 509 {
 510         return modify_aliasmem(alias, member, LDB_FLAG_MOD_DELETE);
 511 }
 512
 513
 514 /*
 515   enumerate sids that have the given alias set in member
 516 */
 517  NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
 518 {
 519         const char *attrs[] = {
 520                 "member",
 521                 NULL
 522         };
 523         int ret, i;
 524         struct ldb_result *res=NULL;
 525         struct ldb_dn *dn;
 526         struct ldb_message_element *el;
 527
 528         if (!init_group_mapping()) {
 529                 return NT_STATUS_ACCESS_DENIED;
 530         }
 531
 532         *sids = NULL;
 533         *num = 0;
 534
 535         dn = mapping_dn(ldb, alias);
 536         if (dn == NULL) {
 537                 return NT_STATUS_NO_MEMORY;
 538         }
 539
 540         ret = ldb_search(ldb, dn, LDB_SCOPE_BASE, NULL, attrs, &res);
 541         talloc_steal(dn, res);
 542         if (ret == LDB_SUCCESS && res->count == 0) {
 543                 talloc_free(dn);
 544                 return NT_STATUS_OK;
 545         }
 546         if (ret != LDB_SUCCESS) {
 547                 talloc_free(dn);
 548                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 549         }
 550
 551         el = ldb_msg_find_element(res->msgs[0], "member");
 552         if (el == NULL) {
 553                 talloc_free(dn);
 554                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 555         }
 556
 557         for (i=0;i<el->num_values;i++) {
 558                 DOM_SID sid;
 559                 string_to_sid(&sid, (const char *)el->values[i].data);
 560                 if (!add_sid_to_array_unique(NULL, &sid, sids, num)) {
 561                         talloc_free(dn);
 562                         return NT_STATUS_NO_MEMORY;
 563                 }
 564         }
 565         talloc_free(dn);
 566
 567         return NT_STATUS_OK;
 568 }
 569
 570 /*
 571   upgrade one group mapping record from the old tdb format
 572 */
 573 static int upgrade_map_record(TDB_CONTEXT *tdb_ctx, TDB_DATA key,
 574                               TDB_DATA data, void *state)
 575 {
 576         int ret;
 577         GROUP_MAP map;
 578
 579         if (strncmp(key.dptr, GROUP_PREFIX,
 580                     MIN(key.dsize, strlen(GROUP_PREFIX))) != 0) {
 581                 return 0;
 582         }
 583
 584         if (!string_to_sid(&map.sid, strlen(GROUP_PREFIX) + (const char *)key.dptr)) {
 585                 DEBUG(0,("Bad sid key '%s' during upgrade\n", (const char *)key.dptr));
 586                 *(int *)state = -1;
 587                 return -1;
 588         }
 589
 590         ret = tdb_unpack(data.dptr, data.dsize, "ddff",
 591                          &map.gid, &map.sid_name_use, &map.nt_name, &map.comment);
 592         if (ret == -1) {
 593                 DEBUG(0,("Failed to unpack group map record during upgrade\n"));
 594                 *(int *)state = -1;
 595                 return -1;
 596         }
 597
 598         if (!add_mapping_entry(&map, 0)) {
 599                 DEBUG(0,("Failed to add mapping entry during upgrade\n"));
 600                 *(int *)state = -1;
 601                 return -1;
 602         }
 603
 604         return 0;
 605 }
 606
 607 /*
 608   upgrade one alias record from the old tdb format
 609 */
 610 static int upgrade_alias_record(TDB_CONTEXT *tdb_ctx, TDB_DATA key,
 611                                 TDB_DATA data, void *state)
 612 {
 613         const char *p = data.dptr;
 614         fstring string_sid;
 615         DOM_SID member;
 616
 617         if (strncmp(key.dptr, MEMBEROF_PREFIX,
 618                     MIN(key.dsize, strlen(MEMBEROF_PREFIX))) != 0) {
 619                 return 0;
 620         }
 621
 622         if (!string_to_sid(&member, strlen(MEMBEROF_PREFIX) + (const char *)key.dptr)) {
 623                 DEBUG(0,("Bad alias key %s during upgrade\n",
 624                          (const char *)key.dptr));
 625                 *(int *)state = -1;
 626         }
 627
 628         while (next_token(&p, string_sid, " ", sizeof(string_sid))) {
 629                 DOM_SID alias;
 630                 NTSTATUS status;
 631                 string_to_sid(&alias, string_sid);
 632                 status = add_aliasmem(&alias, &member);
 633                 if (NT_STATUS_EQUAL(status, NT_STATUS_NO_SUCH_ALIAS)) {
 634                         DEBUG(0,("Ignoring orphaned alias record '%s'\n",
 635                                  string_sid));
 636                 } else if (!NT_STATUS_IS_OK(status)) {
 637                         DEBUG(0,("Failed to add alias member during upgrade - %s\n",
 638                                  nt_errstr(status)));
 639                         *(int *)state = -1;
 640                         return -1;
 641                 }
 642         }
 643
 644         return 0;
 645 }
 646
 647 /*
 648   upgrade from a old style tdb
 649 */
 650 static BOOL mapping_upgrade(const char *tdb_path)
 651 {
 652         static TDB_CONTEXT *tdb;
 653         int ret, status=0;
 654         pstring old_path;
 655         pstring new_path;
 656
 657         tdb = tdb_open_log(tdb_path, 0, TDB_DEFAULT, O_RDWR, 0600);
 658         if (tdb == NULL) goto failed;
 659
 660         /* we have to do the map records first, as alias records may
 661            reference them */
 662         ret = tdb_traverse(tdb, upgrade_map_record, &status);
 663         if (ret == -1 || status == -1) goto failed;
 664
 665         ret = tdb_traverse(tdb, upgrade_alias_record, &status);
 666         if (ret == -1 || status == -1) goto failed;
 667
 668         if (tdb) {
 669                 tdb_close(tdb);
 670                 tdb = NULL;
 671         }
 672
 673         pstrcpy(old_path, tdb_path);
 674         pstrcpy(new_path, lock_path("group_mapping.tdb.upgraded"));
 675
 676         if (rename(old_path, new_path) != 0) {
 677                 DEBUG(0,("Failed to rename old group mapping database\n"));
 678                 goto failed;
 679         }
 680         return True;
 681
 682 failed:
 683         DEBUG(0,("Failed to upgrade group mapping database\n"));
 684         if (tdb) tdb_close(tdb);
 685         return False;
 686 }