source3/groupdb/mapping_tdb.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  RPC Pipe client / server routines
   4  *  Copyright (C) Andrew Tridgell              1992-2006,
   5  *  Copyright (C) Jean François Micouleau      1998-2001.
   6  *  Copyright (C) Volker Lendecke              2006.
   7  *  Copyright (C) Gerald Carter                2006.
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 3 of the License, or
  12  *  (at your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful,
  15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *  GNU General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License
  20  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 #include "includes.h"
  24 #include "groupdb/mapping.h"
  25
  26 static TDB_CONTEXT *tdb; /* used for driver files */
  27
  28 static bool enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
  29                                size_t *p_num_entries, bool unix_only);
  30 static bool group_map_remove(const DOM_SID *sid);
  31
  32 /****************************************************************************
  33  Open the group mapping tdb.
  34 ****************************************************************************/
  35 static bool init_group_mapping(void)
  36 {
  37         const char *vstring = "INFO/version";
  38         int32 vers_id;
  39         GROUP_MAP *map_table = NULL;
  40         size_t num_entries = 0;
  41
  42         if (tdb)
  43                 return True;
  44
  45         tdb = tdb_open_log(state_path("group_mapping.tdb"), 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
  46         if (!tdb) {
  47                 DEBUG(0,("Failed to open group mapping database\n"));
  48                 return False;
  49         }
  50
  51         /* handle a Samba upgrade */
  52         tdb_lock_bystring(tdb, vstring);
  53
  54         /* Cope with byte-reversed older versions of the db. */
  55         vers_id = tdb_fetch_int32(tdb, vstring);
  56         if ((vers_id == DATABASE_VERSION_V1) || (IREV(vers_id) == DATABASE_VERSION_V1)) {
  57                 /* Written on a bigendian machine with old fetch_int code. Save as le. */
  58                 tdb_store_int32(tdb, vstring, DATABASE_VERSION_V2);
  59                 vers_id = DATABASE_VERSION_V2;
  60         }
  61
  62         /* if its an unknown version we remove everthing in the db */
  63
  64         if (vers_id != DATABASE_VERSION_V2) {
  65                 tdb_traverse(tdb, tdb_traverse_delete_fn, NULL);
  66                 tdb_store_int32(tdb, vstring, DATABASE_VERSION_V2);
  67         }
  68
  69         tdb_unlock_bystring(tdb, vstring);
  70
  71         /* cleanup any map entries with a gid == -1 */
  72
  73         if ( enum_group_mapping( NULL, SID_NAME_UNKNOWN, &map_table, &num_entries, False ) ) {
  74                 int i;
  75
  76                 for ( i=0; i<num_entries; i++ ) {
  77                         if ( map_table[i].gid == -1 ) {
  78                                 group_map_remove( &map_table[i].sid );
  79                         }
  80                 }
  81
  82                 SAFE_FREE( map_table );
  83         }
  84
  85
  86         return True;
  87 }
  88
  89 /****************************************************************************
  90 ****************************************************************************/
  91 static bool add_mapping_entry(GROUP_MAP *map, int flag)
  92 {
  93         TDB_DATA dbuf;
  94         char *key = NULL;
  95         char *buf = NULL;
  96         fstring string_sid="";
  97         int len;
  98         bool ret;
  99
 100         sid_to_string(string_sid, &map->sid);
 101
 102         len = tdb_pack(NULL, sizeof(buf), "ddff",
 103                 map->gid, map->sid_name_use, map->nt_name, map->comment);
 104         if (len) {
 105                 buf = SMB_MALLOC_ARRAY(char, len);
 106                 if (!buf) {
 107                         return false;
 108                 }
 109                 len = tdb_pack((uint8 *)buf, sizeof(buf), "ddff", map->gid,
 110                                 map->sid_name_use, map->nt_name, map->comment);
 111         }
 112
 113         if (asprintf(&key, "%s%s", GROUP_PREFIX, string_sid) < 0) {
 114                 SAFE_FREE(buf);
 115                 return false;
 116         }
 117
 118         dbuf.dsize = len;
 119         dbuf.dptr = (uint8 *)buf;
 120
 121         ret = (tdb_store_bystring(tdb, key, dbuf, flag) == 0);
 122
 123         SAFE_FREE(key);
 124         SAFE_FREE(buf);
 125         return ret;
 126 }
 127
 128
 129 /****************************************************************************
 130  Return the sid and the type of the unix group.
 131 ****************************************************************************/
 132
 133 static bool get_group_map_from_sid(DOM_SID sid, GROUP_MAP *map)
 134 {
 135         TDB_DATA dbuf;
 136         char *key = NULL;
 137         fstring string_sid;
 138         int ret = 0;
 139
 140         /* the key is the SID, retrieving is direct */
 141
 142         sid_to_string(string_sid, &sid);
 143         if (asprintf(&key, "%s%s", GROUP_PREFIX, string_sid) < 0) {
 144                 return false;
 145         }
 146
 147         dbuf = tdb_fetch_bystring(tdb, key);
 148         if (!dbuf.dptr) {
 149                 SAFE_FREE(key);
 150                 return false;
 151         }
 152
 153         SAFE_FREE(key);
 154
 155         ret = tdb_unpack(dbuf.dptr, dbuf.dsize, "ddff",
 156                         &map->gid, &map->sid_name_use,
 157                         &map->nt_name, &map->comment);
 158
 159         SAFE_FREE(dbuf.dptr);
 160
 161         if ( ret == -1 ) {
 162                 DEBUG(3,("get_group_map_from_sid: tdb_unpack failure\n"));
 163                 return False;
 164         }
 165
 166         sid_copy(&map->sid, &sid);
 167
 168         return True;
 169 }
 170
 171 /****************************************************************************
 172  Return the sid and the type of the unix group.
 173 ****************************************************************************/
 174
 175 static bool get_group_map_from_gid(gid_t gid, GROUP_MAP *map)
 176 {
 177         TDB_DATA kbuf, dbuf, newkey;
 178         fstring string_sid;
 179         int ret;
 180
 181         /* we need to enumerate the TDB to find the GID */
 182
 183         for (kbuf = tdb_firstkey(tdb);
 184              kbuf.dptr;
 185              newkey = tdb_nextkey(tdb, kbuf), safe_free(kbuf.dptr), kbuf=newkey) {
 186
 187                 if (strncmp((const char *)kbuf.dptr, GROUP_PREFIX, strlen(GROUP_PREFIX)) != 0) continue;
 188
 189                 dbuf = tdb_fetch(tdb, kbuf);
 190                 if (!dbuf.dptr)
 191                         continue;
 192
 193                 fstrcpy(string_sid, (const char *)kbuf.dptr+strlen(GROUP_PREFIX));
 194
 195                 string_to_sid(&map->sid, string_sid);
 196
 197                 ret = tdb_unpack(dbuf.dptr, dbuf.dsize, "ddff",
 198                                  &map->gid, &map->sid_name_use, &map->nt_name, &map->comment);
 199
 200                 SAFE_FREE(dbuf.dptr);
 201
 202                 if ( ret == -1 ) {
 203                         DEBUG(3,("get_group_map_from_gid: tdb_unpack failure\n"));
 204                         return False;
 205                 }
 206
 207                 if (gid==map->gid) {
 208                         SAFE_FREE(kbuf.dptr);
 209                         return True;
 210                 }
 211         }
 212
 213         return False;
 214 }
 215
 216 /****************************************************************************
 217  Return the sid and the type of the unix group.
 218 ****************************************************************************/
 219
 220 static bool get_group_map_from_ntname(const char *name, GROUP_MAP *map)
 221 {
 222         TDB_DATA kbuf, dbuf, newkey;
 223         fstring string_sid;
 224         int ret;
 225
 226         /* we need to enumerate the TDB to find the name */
 227
 228         for (kbuf = tdb_firstkey(tdb);
 229              kbuf.dptr;
 230              newkey = tdb_nextkey(tdb, kbuf), safe_free(kbuf.dptr), kbuf=newkey) {
 231
 232                 if (strncmp((const char *)kbuf.dptr, GROUP_PREFIX, strlen(GROUP_PREFIX)) != 0) continue;
 233
 234                 dbuf = tdb_fetch(tdb, kbuf);
 235                 if (!dbuf.dptr)
 236                         continue;
 237
 238                 fstrcpy(string_sid, (const char *)kbuf.dptr+strlen(GROUP_PREFIX));
 239
 240                 string_to_sid(&map->sid, string_sid);
 241
 242                 ret = tdb_unpack(dbuf.dptr, dbuf.dsize, "ddff",
 243                                  &map->gid, &map->sid_name_use, &map->nt_name, &map->comment);
 244
 245                 SAFE_FREE(dbuf.dptr);
 246
 247                 if ( ret == -1 ) {
 248                         DEBUG(3,("get_group_map_from_ntname: tdb_unpack failure\n"));
 249                         return False;
 250                 }
 251
 252                 if ( strequal(name, map->nt_name) ) {
 253                         SAFE_FREE(kbuf.dptr);
 254                         return True;
 255                 }
 256         }
 257
 258         return False;
 259 }
 260
 261 /****************************************************************************
 262  Remove a group mapping entry.
 263 ****************************************************************************/
 264
 265 static bool group_map_remove(const DOM_SID *sid)
 266 {
 267         TDB_DATA dbuf;
 268         char *key = NULL;
 269         fstring string_sid;
 270         bool ret;
 271
 272         /* the key is the SID, retrieving is direct */
 273
 274         sid_to_string(string_sid, sid);
 275         if (asprintf(&key, "%s%s", GROUP_PREFIX, string_sid) < 0) {
 276                 return false;
 277         }
 278
 279         dbuf = tdb_fetch_bystring(tdb, key);
 280         if (!dbuf.dptr) {
 281                 SAFE_FREE(key);
 282                 return false;
 283         }
 284
 285         SAFE_FREE(dbuf.dptr);
 286
 287         ret = (tdb_delete_bystring(tdb, key) == TDB_SUCCESS);
 288         SAFE_FREE(key);
 289         return ret;
 290 }
 291
 292 /****************************************************************************
 293  Enumerate the group mapping.
 294 ****************************************************************************/
 295
 296 static bool enum_group_mapping(const DOM_SID *domsid, enum lsa_SidType sid_name_use, GROUP_MAP **pp_rmap,
 297                         size_t *p_num_entries, bool unix_only)
 298 {
 299         TDB_DATA kbuf, dbuf, newkey;
 300         fstring string_sid;
 301         GROUP_MAP map;
 302         GROUP_MAP *mapt;
 303         int ret;
 304         size_t entries=0;
 305         DOM_SID grpsid;
 306         uint32 rid;
 307
 308         *p_num_entries=0;
 309         *pp_rmap=NULL;
 310
 311         for (kbuf = tdb_firstkey(tdb);
 312              kbuf.dptr;
 313              newkey = tdb_nextkey(tdb, kbuf), safe_free(kbuf.dptr), kbuf=newkey) {
 314
 315                 if (strncmp((const char *)kbuf.dptr, GROUP_PREFIX, strlen(GROUP_PREFIX)) != 0)
 316                         continue;
 317
 318                 dbuf = tdb_fetch(tdb, kbuf);
 319                 if (!dbuf.dptr)
 320                         continue;
 321
 322                 fstrcpy(string_sid, (const char *)kbuf.dptr+strlen(GROUP_PREFIX));
 323
 324                 ret = tdb_unpack(dbuf.dptr, dbuf.dsize, "ddff",
 325                                  &map.gid, &map.sid_name_use, &map.nt_name, &map.comment);
 326
 327                 SAFE_FREE(dbuf.dptr);
 328
 329                 if ( ret == -1 ) {
 330                         DEBUG(3,("enum_group_mapping: tdb_unpack failure\n"));
 331                         continue;
 332                 }
 333
 334                 /* list only the type or everything if UNKNOWN */
 335                 if (sid_name_use!=SID_NAME_UNKNOWN  && sid_name_use!=map.sid_name_use) {
 336                         DEBUG(11,("enum_group_mapping: group %s is not of the requested type\n", map.nt_name));
 337                         continue;
 338                 }
 339
 340                 if (unix_only==ENUM_ONLY_MAPPED && map.gid==-1) {
 341                         DEBUG(11,("enum_group_mapping: group %s is non mapped\n", map.nt_name));
 342                         continue;
 343                 }
 344
 345                 string_to_sid(&grpsid, string_sid);
 346                 sid_copy( &map.sid, &grpsid );
 347
 348                 sid_split_rid( &grpsid, &rid );
 349
 350                 /* Only check the domain if we were given one */
 351
 352                 if ( domsid && !sid_equal( domsid, &grpsid ) ) {
 353                         DEBUG(11,("enum_group_mapping: group %s is not in domain %s\n",
 354                                 string_sid, sid_string_static(domsid)));
 355                         continue;
 356                 }
 357
 358                 DEBUG(11,("enum_group_mapping: returning group %s of "
 359                           "type %s\n", map.nt_name,
 360                           sid_type_lookup(map.sid_name_use)));
 361
 362                 (*pp_rmap) = SMB_REALLOC_ARRAY((*pp_rmap), GROUP_MAP, entries+1);
 363                 if (!(*pp_rmap)) {
 364                         DEBUG(0,("enum_group_mapping: Unable to enlarge group map!\n"));
 365                         return False;
 366                 }
 367
 368                 mapt = (*pp_rmap);
 369
 370                 mapt[entries].gid = map.gid;
 371                 sid_copy( &mapt[entries].sid, &map.sid);
 372                 mapt[entries].sid_name_use = map.sid_name_use;
 373                 fstrcpy(mapt[entries].nt_name, map.nt_name);
 374                 fstrcpy(mapt[entries].comment, map.comment);
 375
 376                 entries++;
 377
 378         }
 379
 380         *p_num_entries=entries;
 381
 382         return True;
 383 }
 384
 385 /* This operation happens on session setup, so it should better be fast. We
 386  * store a list of aliases a SID is member of hanging off MEMBEROF/SID. */
 387
 388 static NTSTATUS one_alias_membership(const DOM_SID *member,
 389                                DOM_SID **sids, size_t *num)
 390 {
 391         fstring key, string_sid;
 392         TDB_DATA dbuf;
 393         const char *p;
 394
 395         sid_to_string(string_sid, member);
 396         slprintf(key, sizeof(key), "%s%s", MEMBEROF_PREFIX, string_sid);
 397
 398         dbuf = tdb_fetch_bystring(tdb, key);
 399
 400         if (dbuf.dptr == NULL) {
 401                 return NT_STATUS_OK;
 402         }
 403
 404         p = (const char *)dbuf.dptr;
 405
 406         while (next_token(&p, string_sid, " ", sizeof(string_sid))) {
 407
 408                 DOM_SID alias;
 409
 410                 if (!string_to_sid(&alias, string_sid))
 411                         continue;
 412
 413                 if (!add_sid_to_array_unique(NULL, &alias, sids, num)) {
 414                         return NT_STATUS_NO_MEMORY;
 415                 }
 416         }
 417
 418         SAFE_FREE(dbuf.dptr);
 419         return NT_STATUS_OK;
 420 }
 421
 422 static NTSTATUS alias_memberships(const DOM_SID *members, size_t num_members,
 423                                   DOM_SID **sids, size_t *num)
 424 {
 425         size_t i;
 426
 427         *num = 0;
 428         *sids = NULL;
 429
 430         for (i=0; i<num_members; i++) {
 431                 NTSTATUS status = one_alias_membership(&members[i], sids, num);
 432                 if (!NT_STATUS_IS_OK(status))
 433                         return status;
 434         }
 435         return NT_STATUS_OK;
 436 }
 437
 438 static bool is_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 439 {
 440         DOM_SID *sids;
 441         size_t i, num;
 442
 443         /* This feels the wrong way round, but the on-disk data structure
 444          * dictates it this way. */
 445         if (!NT_STATUS_IS_OK(alias_memberships(member, 1, &sids, &num)))
 446                 return False;
 447
 448         for (i=0; i<num; i++) {
 449                 if (sid_compare(alias, &sids[i]) == 0) {
 450                         TALLOC_FREE(sids);
 451                         return True;
 452                 }
 453         }
 454         TALLOC_FREE(sids);
 455         return False;
 456 }
 457
 458
 459 static NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 460 {
 461         GROUP_MAP map;
 462         TDB_DATA dbuf;
 463         char *key = NULL;
 464         fstring string_sid;
 465         char *new_memberstring;
 466         int result;
 467
 468         if (!get_group_map_from_sid(*alias, &map))
 469                 return NT_STATUS_NO_SUCH_ALIAS;
 470
 471         if ( (map.sid_name_use != SID_NAME_ALIAS) &&
 472              (map.sid_name_use != SID_NAME_WKN_GRP) )
 473                 return NT_STATUS_NO_SUCH_ALIAS;
 474
 475         if (is_aliasmem(alias, member))
 476                 return NT_STATUS_MEMBER_IN_ALIAS;
 477
 478         sid_to_string(string_sid, member);
 479         if (asprintf(&key, "%s%s", MEMBEROF_PREFIX, string_sid) < 0) {
 480                 return NT_STATUS_NO_MEMORY;
 481         }
 482
 483         dbuf = tdb_fetch_bystring(tdb, key);
 484
 485         sid_to_string(string_sid, alias);
 486
 487         if (dbuf.dptr != NULL) {
 488                 asprintf(&new_memberstring, "%s %s", (char *)(dbuf.dptr),
 489                          string_sid);
 490         } else {
 491                 new_memberstring = SMB_STRDUP(string_sid);
 492         }
 493
 494         if (new_memberstring == NULL) {
 495                 SAFE_FREE(key);
 496                 return NT_STATUS_NO_MEMORY;
 497         }
 498
 499         SAFE_FREE(dbuf.dptr);
 500         dbuf = string_term_tdb_data(new_memberstring);
 501
 502         result = tdb_store_bystring(tdb, key, dbuf, 0);
 503
 504         SAFE_FREE(new_memberstring);
 505         SAFE_FREE(key);
 506
 507         return (result == 0 ? NT_STATUS_OK : NT_STATUS_ACCESS_DENIED);
 508 }
 509
 510 struct aliasmem_closure {
 511         const DOM_SID *alias;
 512         DOM_SID **sids;
 513         size_t *num;
 514 };
 515
 516 static int collect_aliasmem(TDB_CONTEXT *tdb_ctx, TDB_DATA key, TDB_DATA data,
 517                             void *state)
 518 {
 519         struct aliasmem_closure *closure = (struct aliasmem_closure *)state;
 520         const char *p;
 521         fstring alias_string;
 522
 523         if (strncmp((const char *)key.dptr, MEMBEROF_PREFIX,
 524                     strlen(MEMBEROF_PREFIX)) != 0)
 525                 return 0;
 526
 527         p = (const char *)data.dptr;
 528
 529         while (next_token(&p, alias_string, " ", sizeof(alias_string))) {
 530
 531                 DOM_SID alias, member;
 532                 const char *member_string;
 533
 534
 535                 if (!string_to_sid(&alias, alias_string))
 536                         continue;
 537
 538                 if (sid_compare(closure->alias, &alias) != 0)
 539                         continue;
 540
 541                 /* Ok, we found the alias we're looking for in the membership
 542                  * list currently scanned. The key represents the alias
 543                  * member. Add that. */
 544
 545                 member_string = strchr((const char *)key.dptr, '/');
 546
 547                 /* Above we tested for MEMBEROF_PREFIX which includes the
 548                  * slash. */
 549
 550                 SMB_ASSERT(member_string != NULL);
 551                 member_string += 1;
 552
 553                 if (!string_to_sid(&member, member_string))
 554                         continue;
 555
 556                 if (!add_sid_to_array(NULL, &member, closure->sids, closure->num)) {
 557                         /* talloc fail. */
 558                         break;
 559                 }
 560         }
 561
 562         return 0;
 563 }
 564
 565 static NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
 566 {
 567         GROUP_MAP map;
 568         struct aliasmem_closure closure;
 569
 570         if (!get_group_map_from_sid(*alias, &map))
 571                 return NT_STATUS_NO_SUCH_ALIAS;
 572
 573         if ( (map.sid_name_use != SID_NAME_ALIAS) &&
 574              (map.sid_name_use != SID_NAME_WKN_GRP) )
 575                 return NT_STATUS_NO_SUCH_ALIAS;
 576
 577         *sids = NULL;
 578         *num = 0;
 579
 580         closure.alias = alias;
 581         closure.sids = sids;
 582         closure.num = num;
 583
 584         tdb_traverse(tdb, collect_aliasmem, &closure);
 585         return NT_STATUS_OK;
 586 }
 587
 588 static NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 589 {
 590         NTSTATUS result;
 591         DOM_SID *sids;
 592         size_t i, num;
 593         bool found = False;
 594         char *member_string;
 595         TDB_DATA dbuf;
 596         char *key = NULL;
 597         fstring sid_string;
 598
 599         result = alias_memberships(member, 1, &sids, &num);
 600
 601         if (!NT_STATUS_IS_OK(result))
 602                 return result;
 603
 604         for (i=0; i<num; i++) {
 605                 if (sid_compare(&sids[i], alias) == 0) {
 606                         found = True;
 607                         break;
 608                 }
 609         }
 610
 611         if (!found) {
 612                 TALLOC_FREE(sids);
 613                 return NT_STATUS_MEMBER_NOT_IN_ALIAS;
 614         }
 615
 616         if (i < num)
 617                 sids[i] = sids[num-1];
 618
 619         num -= 1;
 620
 621         sid_to_string(sid_string, member);
 622         if (asprintf(&key, "%s%s", MEMBEROF_PREFIX, sid_string) < 0) {
 623                 TALLOC_FREE(sids);
 624                 return NT_STATUS_NO_MEMORY;
 625         }
 626
 627         if (num == 0) {
 628                 NTSTATUS ret = (tdb_delete_bystring(tdb, key) == 0 ?
 629                         NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL);
 630                 TALLOC_FREE(sids);
 631                 SAFE_FREE(key);
 632                 return ret;
 633         }
 634
 635         member_string = SMB_STRDUP("");
 636
 637         if (member_string == NULL) {
 638                 TALLOC_FREE(sids);
 639                 SAFE_FREE(key);
 640                 return NT_STATUS_NO_MEMORY;
 641         }
 642
 643         for (i=0; i<num; i++) {
 644                 char *s = member_string;
 645
 646                 sid_to_string(sid_string, &sids[i]);
 647                 asprintf(&member_string, "%s %s", s, sid_string);
 648
 649                 SAFE_FREE(s);
 650                 if (member_string == NULL) {
 651                         TALLOC_FREE(sids);
 652                         SAFE_FREE(key);
 653                         return NT_STATUS_NO_MEMORY;
 654                 }
 655         }
 656
 657         dbuf = string_term_tdb_data(member_string);
 658
 659         result = tdb_store_bystring(tdb, key, dbuf, 0) == 0 ?
 660                 NT_STATUS_OK : NT_STATUS_ACCESS_DENIED;
 661
 662         TALLOC_FREE(sids);
 663         SAFE_FREE(member_string);
 664         SAFE_FREE(key);
 665
 666         return result;
 667 }
 668
 669
 670 static const struct mapping_backend tdb_backend = {
 671         .add_mapping_entry         = add_mapping_entry,
 672         .get_group_map_from_sid    = get_group_map_from_sid,
 673         .get_group_map_from_gid    = get_group_map_from_gid,
 674         .get_group_map_from_ntname = get_group_map_from_ntname,
 675         .group_map_remove          = group_map_remove,
 676         .enum_group_mapping        = enum_group_mapping,
 677         .one_alias_membership      = one_alias_membership,
 678         .add_aliasmem              = add_aliasmem,
 679         .del_aliasmem              = del_aliasmem,
 680         .enum_aliasmem             = enum_aliasmem
 681 };
 682
 683 /*
 684   initialise the tdb mapping backend
 685  */
 686 const struct mapping_backend *groupdb_tdb_init(void)
 687 {
 688         if (!init_group_mapping()) {
 689                 DEBUG(0,("Failed to initialise tdb mapping backend\n"));
 690                 return NULL;
 691         }
 692
 693         return &tdb_backend;
 694 }