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;
 392         char *string_sid;
 393         TDB_DATA dbuf;
 394         const char *p;
 395         TALLOC_CTX *frame;
 396
 397         slprintf(key, sizeof(key), "%s%s", MEMBEROF_PREFIX,
 398                  sid_string_static(member));
 399
 400         dbuf = tdb_fetch_bystring(tdb, key);
 401
 402         if (dbuf.dptr == NULL) {
 403                 return NT_STATUS_OK;
 404         }
 405
 406         p = (const char *)dbuf.dptr;
 407         frame = talloc_stackframe();
 408         while (next_token_talloc(frame, &p, &string_sid, " ")) {
 409                 DOM_SID alias;
 410
 411                 if (!string_to_sid(&alias, string_sid))
 412                         continue;
 413
 414                 if (!add_sid_to_array_unique(NULL, &alias, sids, num)) {
 415                         TALLOC_FREE(frame);
 416                         return NT_STATUS_NO_MEMORY;
 417                 }
 418         }
 419
 420         TALLOC_FREE(frame);
 421         SAFE_FREE(dbuf.dptr);
 422         return NT_STATUS_OK;
 423 }
 424
 425 static NTSTATUS alias_memberships(const DOM_SID *members, size_t num_members,
 426                                   DOM_SID **sids, size_t *num)
 427 {
 428         size_t i;
 429
 430         *num = 0;
 431         *sids = NULL;
 432
 433         for (i=0; i<num_members; i++) {
 434                 NTSTATUS status = one_alias_membership(&members[i], sids, num);
 435                 if (!NT_STATUS_IS_OK(status))
 436                         return status;
 437         }
 438         return NT_STATUS_OK;
 439 }
 440
 441 static bool is_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 442 {
 443         DOM_SID *sids;
 444         size_t i, num;
 445
 446         /* This feels the wrong way round, but the on-disk data structure
 447          * dictates it this way. */
 448         if (!NT_STATUS_IS_OK(alias_memberships(member, 1, &sids, &num)))
 449                 return False;
 450
 451         for (i=0; i<num; i++) {
 452                 if (sid_compare(alias, &sids[i]) == 0) {
 453                         TALLOC_FREE(sids);
 454                         return True;
 455                 }
 456         }
 457         TALLOC_FREE(sids);
 458         return False;
 459 }
 460
 461
 462 static NTSTATUS add_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 463 {
 464         GROUP_MAP map;
 465         TDB_DATA dbuf;
 466         char *key = NULL;
 467         fstring string_sid;
 468         char *new_memberstring;
 469         int result;
 470
 471         if (!get_group_map_from_sid(*alias, &map))
 472                 return NT_STATUS_NO_SUCH_ALIAS;
 473
 474         if ( (map.sid_name_use != SID_NAME_ALIAS) &&
 475              (map.sid_name_use != SID_NAME_WKN_GRP) )
 476                 return NT_STATUS_NO_SUCH_ALIAS;
 477
 478         if (is_aliasmem(alias, member))
 479                 return NT_STATUS_MEMBER_IN_ALIAS;
 480
 481         sid_to_string(string_sid, member);
 482         if (asprintf(&key, "%s%s", MEMBEROF_PREFIX, string_sid) < 0) {
 483                 return NT_STATUS_NO_MEMORY;
 484         }
 485
 486         dbuf = tdb_fetch_bystring(tdb, key);
 487
 488         sid_to_string(string_sid, alias);
 489
 490         if (dbuf.dptr != NULL) {
 491                 asprintf(&new_memberstring, "%s %s", (char *)(dbuf.dptr),
 492                          string_sid);
 493         } else {
 494                 new_memberstring = SMB_STRDUP(string_sid);
 495         }
 496
 497         if (new_memberstring == NULL) {
 498                 SAFE_FREE(key);
 499                 return NT_STATUS_NO_MEMORY;
 500         }
 501
 502         SAFE_FREE(dbuf.dptr);
 503         dbuf = string_term_tdb_data(new_memberstring);
 504
 505         result = tdb_store_bystring(tdb, key, dbuf, 0);
 506
 507         SAFE_FREE(new_memberstring);
 508         SAFE_FREE(key);
 509
 510         return (result == 0 ? NT_STATUS_OK : NT_STATUS_ACCESS_DENIED);
 511 }
 512
 513 struct aliasmem_closure {
 514         const DOM_SID *alias;
 515         DOM_SID **sids;
 516         size_t *num;
 517 };
 518
 519 static int collect_aliasmem(TDB_CONTEXT *tdb_ctx, TDB_DATA key, TDB_DATA data,
 520                             void *state)
 521 {
 522         struct aliasmem_closure *closure = (struct aliasmem_closure *)state;
 523         const char *p;
 524         char *alias_string;
 525         TALLOC_CTX *frame;
 526
 527         if (strncmp((const char *)key.dptr, MEMBEROF_PREFIX,
 528                     strlen(MEMBEROF_PREFIX)) != 0)
 529                 return 0;
 530
 531         p = (const char *)data.dptr;
 532
 533         frame = talloc_stackframe();
 534         while (next_token_talloc(frame, &p, &alias_string, " ")) {
 535                 DOM_SID alias, member;
 536                 const char *member_string;
 537
 538                 if (!string_to_sid(&alias, alias_string))
 539                         continue;
 540
 541                 if (sid_compare(closure->alias, &alias) != 0)
 542                         continue;
 543
 544                 /* Ok, we found the alias we're looking for in the membership
 545                  * list currently scanned. The key represents the alias
 546                  * member. Add that. */
 547
 548                 member_string = strchr((const char *)key.dptr, '/');
 549
 550                 /* Above we tested for MEMBEROF_PREFIX which includes the
 551                  * slash. */
 552
 553                 SMB_ASSERT(member_string != NULL);
 554                 member_string += 1;
 555
 556                 if (!string_to_sid(&member, member_string))
 557                         continue;
 558
 559                 if (!add_sid_to_array(NULL, &member, closure->sids, closure->num)) {
 560                         /* talloc fail. */
 561                         break;
 562                 }
 563         }
 564
 565         TALLOC_FREE(frame);
 566         return 0;
 567 }
 568
 569 static NTSTATUS enum_aliasmem(const DOM_SID *alias, DOM_SID **sids, size_t *num)
 570 {
 571         GROUP_MAP map;
 572         struct aliasmem_closure closure;
 573
 574         if (!get_group_map_from_sid(*alias, &map))
 575                 return NT_STATUS_NO_SUCH_ALIAS;
 576
 577         if ( (map.sid_name_use != SID_NAME_ALIAS) &&
 578              (map.sid_name_use != SID_NAME_WKN_GRP) )
 579                 return NT_STATUS_NO_SUCH_ALIAS;
 580
 581         *sids = NULL;
 582         *num = 0;
 583
 584         closure.alias = alias;
 585         closure.sids = sids;
 586         closure.num = num;
 587
 588         tdb_traverse(tdb, collect_aliasmem, &closure);
 589         return NT_STATUS_OK;
 590 }
 591
 592 static NTSTATUS del_aliasmem(const DOM_SID *alias, const DOM_SID *member)
 593 {
 594         NTSTATUS result;
 595         DOM_SID *sids;
 596         size_t i, num;
 597         bool found = False;
 598         char *member_string;
 599         TDB_DATA dbuf;
 600         char *key = NULL;
 601         fstring sid_string;
 602
 603         result = alias_memberships(member, 1, &sids, &num);
 604
 605         if (!NT_STATUS_IS_OK(result))
 606                 return result;
 607
 608         for (i=0; i<num; i++) {
 609                 if (sid_compare(&sids[i], alias) == 0) {
 610                         found = True;
 611                         break;
 612                 }
 613         }
 614
 615         if (!found) {
 616                 TALLOC_FREE(sids);
 617                 return NT_STATUS_MEMBER_NOT_IN_ALIAS;
 618         }
 619
 620         if (i < num)
 621                 sids[i] = sids[num-1];
 622
 623         num -= 1;
 624
 625         sid_to_string(sid_string, member);
 626         if (asprintf(&key, "%s%s", MEMBEROF_PREFIX, sid_string) < 0) {
 627                 TALLOC_FREE(sids);
 628                 return NT_STATUS_NO_MEMORY;
 629         }
 630
 631         if (num == 0) {
 632                 NTSTATUS ret = (tdb_delete_bystring(tdb, key) == 0 ?
 633                         NT_STATUS_OK : NT_STATUS_UNSUCCESSFUL);
 634                 TALLOC_FREE(sids);
 635                 SAFE_FREE(key);
 636                 return ret;
 637         }
 638
 639         member_string = SMB_STRDUP("");
 640
 641         if (member_string == NULL) {
 642                 TALLOC_FREE(sids);
 643                 SAFE_FREE(key);
 644                 return NT_STATUS_NO_MEMORY;
 645         }
 646
 647         for (i=0; i<num; i++) {
 648                 char *s = member_string;
 649
 650                 sid_to_string(sid_string, &sids[i]);
 651                 asprintf(&member_string, "%s %s", s, sid_string);
 652
 653                 SAFE_FREE(s);
 654                 if (member_string == NULL) {
 655                         TALLOC_FREE(sids);
 656                         SAFE_FREE(key);
 657                         return NT_STATUS_NO_MEMORY;
 658                 }
 659         }
 660
 661         dbuf = string_term_tdb_data(member_string);
 662
 663         result = tdb_store_bystring(tdb, key, dbuf, 0) == 0 ?
 664                 NT_STATUS_OK : NT_STATUS_ACCESS_DENIED;
 665
 666         TALLOC_FREE(sids);
 667         SAFE_FREE(member_string);
 668         SAFE_FREE(key);
 669
 670         return result;
 671 }
 672
 673
 674 static const struct mapping_backend tdb_backend = {
 675         .add_mapping_entry         = add_mapping_entry,
 676         .get_group_map_from_sid    = get_group_map_from_sid,
 677         .get_group_map_from_gid    = get_group_map_from_gid,
 678         .get_group_map_from_ntname = get_group_map_from_ntname,
 679         .group_map_remove          = group_map_remove,
 680         .enum_group_mapping        = enum_group_mapping,
 681         .one_alias_membership      = one_alias_membership,
 682         .add_aliasmem              = add_aliasmem,
 683         .del_aliasmem              = del_aliasmem,
 684         .enum_aliasmem             = enum_aliasmem
 685 };
 686
 687 /*
 688   initialise the tdb mapping backend
 689  */
 690 const struct mapping_backend *groupdb_tdb_init(void)
 691 {
 692         if (!init_group_mapping()) {
 693                 DEBUG(0,("Failed to initialise tdb mapping backend\n"));
 694                 return NULL;
 695         }
 696
 697         return &tdb_backend;
 698 }