git.sur5r.net Git - openldap/blob - servers/slapd/back-mdb/search.c

   1 /* search.c - search operation */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2000-2014 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  12  * A copy of this license is available in the file LICENSE in the
  13  * top-level directory of the distribution or, alternatively, at
  14  * <http://www.OpenLDAP.org/license.html>.
  15  */
  16
  17 #include "portable.h"
  18
  19 #include <stdio.h>
  20 #include <ac/string.h>
  21
  22 #include "back-mdb.h"
  23 #include "idl.h"
  24
  25 static int base_candidate(
  26         BackendDB       *be,
  27         Entry   *e,
  28         ID              *ids );
  29
  30 static int search_candidates(
  31         Operation *op,
  32         SlapReply *rs,
  33         Entry *e,
  34         IdScopes *isc,
  35         MDB_cursor *mci,
  36         ID      *ids,
  37         ID *stack );
  38
  39 static int parse_paged_cookie( Operation *op, SlapReply *rs );
  40
  41 static void send_paged_response(
  42         Operation *op,
  43         SlapReply *rs,
  44         ID  *lastid,
  45         int tentries );
  46
  47 /* Dereference aliases for a single alias entry. Return the final
  48  * dereferenced entry on success, NULL on any failure.
  49  */
  50 static Entry * deref_base (
  51         Operation *op,
  52         SlapReply *rs,
  53         Entry *e,
  54         Entry **matched,
  55         MDB_txn *txn,
  56         ID      *tmp,
  57         ID      *visited )
  58 {
  59         struct berval ndn;
  60
  61         rs->sr_err = LDAP_ALIAS_DEREF_PROBLEM;
  62         rs->sr_text = "maximum deref depth exceeded";
  63
  64         for (;;) {
  65                 /* Remember the last entry we looked at, so we can
  66                  * report broken links
  67                  */
  68                 *matched = e;
  69
  70                 if (MDB_IDL_N(tmp) >= op->o_bd->be_max_deref_depth) {
  71                         e = NULL;
  72                         break;
  73                 }
  74
  75                 /* If this is part of a subtree or onelevel search,
  76                  * have we seen this ID before? If so, quit.
  77                  */
  78                 if ( visited && mdb_idl_insert( visited, e->e_id ) ) {
  79                         e = NULL;
  80                         break;
  81                 }
  82
  83                 /* If we've seen this ID during this deref iteration,
  84                  * we've hit a loop.
  85                  */
  86                 if ( mdb_idl_insert( tmp, e->e_id ) ) {
  87                         rs->sr_err = LDAP_ALIAS_PROBLEM;
  88                         rs->sr_text = "circular alias";
  89                         e = NULL;
  90                         break;
  91                 }
  92
  93                 /* If there was a problem getting the aliasedObjectName,
  94                  * get_alias_dn will have set the error status.
  95                  */
  96                 if ( get_alias_dn(e, &ndn, &rs->sr_err, &rs->sr_text) ) {
  97                         e = NULL;
  98                         break;
  99                 }
 100
 101                 rs->sr_err = mdb_dn2entry( op, txn, NULL, &ndn, &e, NULL, 0 );
 102                 if (rs->sr_err) {
 103                         rs->sr_err = LDAP_ALIAS_PROBLEM;
 104                         rs->sr_text = "aliasedObject not found";
 105                         break;
 106                 }
 107
 108                 /* Free the previous entry, continue to work with the
 109                  * one we just retrieved.
 110                  */
 111                 mdb_entry_return( op, *matched );
 112
 113                 /* We found a regular entry. Return this to the caller.
 114                  */
 115                 if (!is_entry_alias(e)) {
 116                         rs->sr_err = LDAP_SUCCESS;
 117                         rs->sr_text = NULL;
 118                         break;
 119                 }
 120         }
 121         return e;
 122 }
 123
 124 /* Look for and dereference all aliases within the search scope.
 125  * Requires "stack" to be able to hold 6 levels of DB_SIZE IDLs.
 126  * Of course we're hardcoded to require a minimum of 8 UM_SIZE
 127  * IDLs so this is never a problem.
 128  */
 129 static int search_aliases(
 130         Operation *op,
 131         SlapReply *rs,
 132         ID e_id,
 133         IdScopes *isc,
 134         MDB_cursor *mci,
 135         ID *stack )
 136 {
 137         ID *aliases, *curscop, *visited, *newsubs, *oldsubs, *tmp;
 138         ID cursora, ida, cursoro, ido;
 139         Entry *matched, *a;
 140         struct berval bv_alias = BER_BVC( "alias" );
 141         AttributeAssertion aa_alias = ATTRIBUTEASSERTION_INIT;
 142         Filter  af;
 143         int first = 1;
 144
 145         aliases = stack;        /* IDL of all aliases in the database */
 146         curscop = aliases + MDB_IDL_DB_SIZE;    /* Aliases in the current scope */
 147         visited = curscop + MDB_IDL_DB_SIZE;    /* IDs we've seen in this search */
 148         newsubs = visited + MDB_IDL_DB_SIZE;    /* New subtrees we've added */
 149         oldsubs = newsubs + MDB_IDL_DB_SIZE;    /* Subtrees added previously */
 150         tmp = oldsubs + MDB_IDL_DB_SIZE;        /* Scratch space for deref_base() */
 151
 152         af.f_choice = LDAP_FILTER_EQUALITY;
 153         af.f_ava = &aa_alias;
 154         af.f_av_desc = slap_schema.si_ad_objectClass;
 155         af.f_av_value = bv_alias;
 156         af.f_next = NULL;
 157
 158         /* Find all aliases in database */
 159         MDB_IDL_ZERO( aliases );
 160         rs->sr_err = mdb_filter_candidates( op, isc->mt, &af, aliases,
 161                 curscop, visited );
 162         if (rs->sr_err != LDAP_SUCCESS || MDB_IDL_IS_ZERO( aliases )) {
 163                 return rs->sr_err;
 164         }
 165         oldsubs[0] = 1;
 166         oldsubs[1] = e_id;
 167
 168         MDB_IDL_ZERO( visited );
 169         MDB_IDL_ZERO( newsubs );
 170
 171         cursoro = 0;
 172         ido = mdb_idl_first( oldsubs, &cursoro );
 173
 174         for (;;) {
 175                 /* Set curscop to only the aliases in the current scope. Start with
 176                  * all the aliases, then get the intersection with the scope.
 177                  */
 178                 rs->sr_err = mdb_idscope( op, isc->mt, e_id, aliases, curscop );
 179
 180                 /* Dereference all of the aliases in the current scope. */
 181                 cursora = 0;
 182                 for (ida = mdb_idl_first(curscop, &cursora); ida != NOID;
 183                         ida = mdb_idl_next(curscop, &cursora))
 184                 {
 185                         rs->sr_err = mdb_id2entry(op, mci, ida, &a);
 186                         if (rs->sr_err != LDAP_SUCCESS) {
 187                                 continue;
 188                         }
 189
 190                         /* This should only happen if the curscop IDL has maxed out and
 191                          * turned into a range that spans IDs indiscriminately
 192                          */
 193                         if (!is_entry_alias(a)) {
 194                                 mdb_entry_return(op, a);
 195                                 continue;
 196                         }
 197
 198                         /* Actually dereference the alias */
 199                         MDB_IDL_ZERO(tmp);
 200                         a = deref_base( op, rs, a, &matched, isc->mt,
 201                                 tmp, visited );
 202                         if (a) {
 203                                 /* If the target was not already in our current scopes,
 204                                  * make note of it in the newsubs list.
 205                                  */
 206                                 ID2 mid;
 207                                 mid.mid = a->e_id;
 208                                 mid.mval.mv_data = NULL;
 209                                 if (op->ors_scope == LDAP_SCOPE_SUBTREE) {
 210                                         isc->id = a->e_id;
 211                                         /* if ID is a child of any of our current scopes,
 212                                          * ignore it, it's already included.
 213                                          */
 214                                         if (mdb_idscopechk(op, isc))
 215                                                 goto skip;
 216                                 }
 217                                 if (mdb_id2l_insert(isc->scopes, &mid) == 0) {
 218                                         mdb_idl_insert(newsubs, a->e_id);
 219                                 }
 220 skip:                   mdb_entry_return( op, a );
 221
 222                         } else if (matched) {
 223                                 /* Alias could not be dereferenced, or it deref'd to
 224                                  * an ID we've already seen. Ignore it.
 225                                  */
 226                                 mdb_entry_return( op, matched );
 227                                 rs->sr_text = NULL;
 228                                 rs->sr_err = 0;
 229                         }
 230                 }
 231                 /* If this is a OneLevel search, we're done; oldsubs only had one
 232                  * ID in it. For a Subtree search, oldsubs may be a list of scope IDs.
 233                  */
 234                 if ( op->ors_scope == LDAP_SCOPE_ONELEVEL ) break;
 235 nextido:
 236                 ido = mdb_idl_next( oldsubs, &cursoro );
 237
 238                 /* If we're done processing the old scopes, did we add any new
 239                  * scopes in this iteration? If so, go back and do those now.
 240                  */
 241                 if (ido == NOID) {
 242                         if (MDB_IDL_IS_ZERO(newsubs)) break;
 243                         MDB_IDL_CPY(oldsubs, newsubs);
 244                         MDB_IDL_ZERO(newsubs);
 245                         cursoro = 0;
 246                         ido = mdb_idl_first( oldsubs, &cursoro );
 247                 }
 248
 249                 /* Find the entry corresponding to the next scope. If it can't
 250                  * be found, ignore it and move on. This should never happen;
 251                  * we should never see the ID of an entry that doesn't exist.
 252                  */
 253                 {
 254                         MDB_val edata;
 255                         rs->sr_err = mdb_id2edata(op, mci, ido, &edata);
 256                         if ( rs->sr_err != MDB_SUCCESS ) {
 257                                 goto nextido;
 258                         }
 259                         e_id = ido;
 260                 }
 261         }
 262         return rs->sr_err;
 263 }
 264
 265 /* Get the next ID from the DB. Used if the candidate list is
 266  * a range and simple iteration hits missing entryIDs
 267  */
 268 static int
 269 mdb_get_nextid(MDB_cursor *mci, ID *cursor)
 270 {
 271         MDB_val key;
 272         ID id;
 273         int rc;
 274
 275         id = *cursor + 1;
 276         key.mv_data = &id;
 277         key.mv_size = sizeof(ID);
 278         rc = mdb_cursor_get( mci, &key, NULL, MDB_SET_RANGE );
 279         if ( rc )
 280                 return rc;
 281         memcpy( cursor, key.mv_data, sizeof(ID));
 282         return 0;
 283 }
 284
 285 static void scope_chunk_free( void *key, void *data )
 286 {
 287         ID2 *p1, *p2;
 288         for (p1 = data; p1; p1 = p2) {
 289                 p2 = p1[0].mval.mv_data;
 290                 ber_memfree_x(p1, NULL);
 291         }
 292 }
 293
 294 static ID2 *scope_chunk_get( Operation *op )
 295 {
 296         struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
 297         ID2 *ret = NULL;
 298
 299         ldap_pvt_thread_pool_getkey( op->o_threadctx, (void *)scope_chunk_get,
 300                         (void *)&ret, NULL );
 301         if ( !ret ) {
 302                 ret = ch_malloc( MDB_IDL_UM_SIZE * sizeof( ID2 ));
 303         } else {
 304                 void *r2 = ret[0].mval.mv_data;
 305                 ldap_pvt_thread_pool_setkey( op->o_threadctx, (void *)scope_chunk_get,
 306                         r2, scope_chunk_free, NULL, NULL );
 307         }
 308         return ret;
 309 }
 310
 311 static void scope_chunk_ret( Operation *op, ID2 *scopes )
 312 {
 313         struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
 314         void *ret = NULL;
 315
 316         ldap_pvt_thread_pool_getkey( op->o_threadctx, (void *)scope_chunk_get,
 317                         &ret, NULL );
 318         scopes[0].mval.mv_data = ret;
 319         ldap_pvt_thread_pool_setkey( op->o_threadctx, (void *)scope_chunk_get,
 320                         (void *)scopes, scope_chunk_free, NULL, NULL );
 321 }
 322
 323 static void *search_stack( Operation *op );
 324
 325 typedef struct ww_ctx {
 326         MDB_txn *txn;
 327         MDB_cursor *mcd;        /* if set, save cursor context */
 328         ID key;
 329         MDB_val data;
 330         int flag;
 331 } ww_ctx;
 332
 333 /* ITS#7904 if we get blocked while writing results to client,
 334  * release the current reader txn and reacquire it after we
 335  * unblock.
 336  * Slight problem - if we're doing a scope-based walk (mdb_dn2id_walk)
 337  * to return results, we need to remember the state of the mcd cursor.
 338  * If the node that cursor was pointing to gets deleted while we're
 339  * blocked, we may be unable to restore the cursor position. In that
 340  * case return an LDAP_BUSY error - let the client know this search
 341  * couldn't succeed, but might succeed on a retry.
 342  */
 343 static void
 344 mdb_writewait( Operation *op, slap_callback *sc )
 345 {
 346         ww_ctx *ww = sc->sc_private;
 347         if ( !ww->flag ) {
 348                 if ( ww->mcd ) {
 349                         MDB_val key, data;
 350                         mdb_cursor_get( ww->mcd, &key, &data, MDB_GET_CURRENT );
 351                         memcpy( &ww->key, key.mv_data, sizeof(ID) );
 352                         ww->data.mv_size = data.mv_size;
 353                         ww->data.mv_data = op->o_tmpalloc( data.mv_size, op->o_tmpmemctx );
 354                         memcpy(ww->data.mv_data, data.mv_data, data.mv_size);
 355                 }
 356                 mdb_txn_reset( ww->txn );
 357                 ww->flag = 1;
 358         }
 359 }
 360
 361 static int
 362 mdb_waitfixup( Operation *op, ww_ctx *ww, MDB_cursor *mci, MDB_cursor *mcd )
 363 {
 364         int rc = 0;
 365         ww->flag = 0;
 366         mdb_txn_renew( ww->txn );
 367         mdb_cursor_renew( ww->txn, mci );
 368         mdb_cursor_renew( ww->txn, mcd );
 369         if ( ww->mcd ) {
 370                 MDB_val key, data;
 371                 key.mv_size = sizeof(ID);
 372                 key.mv_data = &ww->key;
 373                 data = ww->data;
 374                 rc = mdb_cursor_get( mcd, &key, &data, MDB_GET_BOTH );
 375                 if ( rc == MDB_NOTFOUND ) {
 376                         data = ww->data;
 377                         rc = mdb_cursor_get( mcd, &key, &data, MDB_GET_BOTH_RANGE );
 378                         /* the loop will skip this node using NEXT_DUP but we want it
 379                          * sent, so go back one space first
 380                          */
 381                         if ( rc == MDB_SUCCESS )
 382                                 mdb_cursor_get( mcd, &key, &data, MDB_PREV_DUP );
 383                         else
 384                                 rc = LDAP_BUSY;
 385                 } else if ( rc ) {
 386                         rc = LDAP_OTHER;
 387                 }
 388                 op->o_tmpfree( ww->data.mv_data, op->o_tmpmemctx );
 389                 ww->data.mv_data = NULL;
 390         }
 391         return rc;
 392 }
 393
 394 int
 395 mdb_search( Operation *op, SlapReply *rs )
 396 {
 397         struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
 398         ID              id, cursor, nsubs, ncand, cscope;
 399         ID              lastid = NOID;
 400         ID              candidates[MDB_IDL_UM_SIZE];
 401         ID              iscopes[MDB_IDL_DB_SIZE];
 402         ID2             *scopes;
 403         void    *stack;
 404         Entry           *e = NULL, *base = NULL;
 405         Entry           *matched = NULL;
 406         AttributeName   *attrs;
 407         slap_mask_t     mask;
 408         time_t          stoptime;
 409         int             manageDSAit;
 410         int             tentries = 0;
 411         IdScopes        isc;
 412         MDB_cursor      *mci, *mcd;
 413         ww_ctx wwctx;
 414         slap_callback cb = { 0 };
 415
 416         mdb_op_info     opinfo = {{{0}}}, *moi = &opinfo;
 417         MDB_txn                 *ltid = NULL;
 418
 419         Debug( LDAP_DEBUG_TRACE, "=> " LDAP_XSTRING(mdb_search) "\n", 0, 0, 0);
 420         attrs = op->oq_search.rs_attrs;
 421
 422         manageDSAit = get_manageDSAit( op );
 423
 424         rs->sr_err = mdb_opinfo_get( op, mdb, 1, &moi );
 425         switch(rs->sr_err) {
 426         case 0:
 427                 break;
 428         default:
 429                 send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
 430                 return rs->sr_err;
 431         }
 432
 433         ltid = moi->moi_txn;
 434
 435         rs->sr_err = mdb_cursor_open( ltid, mdb->mi_id2entry, &mci );
 436         if ( rs->sr_err ) {
 437                 send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
 438                 return rs->sr_err;
 439         }
 440
 441         rs->sr_err = mdb_cursor_open( ltid, mdb->mi_dn2id, &mcd );
 442         if ( rs->sr_err ) {
 443                 mdb_cursor_close( mci );
 444                 send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
 445                 return rs->sr_err;
 446         }
 447
 448         scopes = scope_chunk_get( op );
 449         stack = search_stack( op );
 450         isc.mt = ltid;
 451         isc.mc = mcd;
 452         isc.scopes = scopes;
 453         isc.oscope = op->ors_scope;
 454         isc.sctmp = stack;
 455
 456         if ( op->ors_deref & LDAP_DEREF_FINDING ) {
 457                 MDB_IDL_ZERO(candidates);
 458         }
 459 dn2entry_retry:
 460         /* get entry with reader lock */
 461         rs->sr_err = mdb_dn2entry( op, ltid, mcd, &op->o_req_ndn, &e, &nsubs, 1 );
 462
 463         switch(rs->sr_err) {
 464         case MDB_NOTFOUND:
 465                 matched = e;
 466                 e = NULL;
 467                 break;
 468         case 0:
 469                 break;
 470         case LDAP_BUSY:
 471                 send_ldap_error( op, rs, LDAP_BUSY, "ldap server busy" );
 472                 goto done;
 473         default:
 474                 send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
 475                 goto done;
 476         }
 477
 478         if ( op->ors_deref & LDAP_DEREF_FINDING ) {
 479                 if ( matched && is_entry_alias( matched )) {
 480                         struct berval stub;
 481
 482                         stub.bv_val = op->o_req_ndn.bv_val;
 483                         stub.bv_len = op->o_req_ndn.bv_len - matched->e_nname.bv_len - 1;
 484                         e = deref_base( op, rs, matched, &matched, ltid,
 485                                 candidates, NULL );
 486                         if ( e ) {
 487                                 build_new_dn( &op->o_req_ndn, &e->e_nname, &stub,
 488                                         op->o_tmpmemctx );
 489                                 mdb_entry_return(op, e);
 490                                 matched = NULL;
 491                                 goto dn2entry_retry;
 492                         }
 493                 } else if ( e && is_entry_alias( e )) {
 494                         e = deref_base( op, rs, e, &matched, ltid,
 495                                 candidates, NULL );
 496                 }
 497         }
 498
 499         if ( e == NULL ) {
 500                 struct berval matched_dn = BER_BVNULL;
 501
 502                 if ( matched != NULL ) {
 503                         BerVarray erefs = NULL;
 504
 505                         /* return referral only if "disclose"
 506                          * is granted on the object */
 507                         if ( ! access_allowed( op, matched,
 508                                                 slap_schema.si_ad_entry,
 509                                                 NULL, ACL_DISCLOSE, NULL ) )
 510                         {
 511                                 rs->sr_err = LDAP_NO_SUCH_OBJECT;
 512
 513                         } else {
 514                                 ber_dupbv( &matched_dn, &matched->e_name );
 515
 516                                 erefs = is_entry_referral( matched )
 517                                         ? get_entry_referrals( op, matched )
 518                                         : NULL;
 519                                 if ( rs->sr_err == MDB_NOTFOUND )
 520                                         rs->sr_err = LDAP_REFERRAL;
 521                                 rs->sr_matched = matched_dn.bv_val;
 522                         }
 523
 524                         mdb_entry_return(op, matched);
 525                         matched = NULL;
 526
 527                         if ( erefs ) {
 528                                 rs->sr_ref = referral_rewrite( erefs, &matched_dn,
 529                                         &op->o_req_dn, op->oq_search.rs_scope );
 530                                 ber_bvarray_free( erefs );
 531                         }
 532
 533                 } else {
 534                         rs->sr_ref = referral_rewrite( default_referral,
 535                                 NULL, &op->o_req_dn, op->oq_search.rs_scope );
 536                         rs->sr_err = rs->sr_ref != NULL ? LDAP_REFERRAL : LDAP_NO_SUCH_OBJECT;
 537                 }
 538
 539                 send_ldap_result( op, rs );
 540
 541                 if ( rs->sr_ref ) {
 542                         ber_bvarray_free( rs->sr_ref );
 543                         rs->sr_ref = NULL;
 544                 }
 545                 if ( !BER_BVISNULL( &matched_dn ) ) {
 546                         ber_memfree( matched_dn.bv_val );
 547                         rs->sr_matched = NULL;
 548                 }
 549                 goto done;
 550         }
 551
 552         /* NOTE: __NEW__ "search" access is required
 553          * on searchBase object */
 554         if ( ! access_allowed_mask( op, e, slap_schema.si_ad_entry,
 555                                 NULL, ACL_SEARCH, NULL, &mask ) )
 556         {
 557                 if ( !ACL_GRANT( mask, ACL_DISCLOSE ) ) {
 558                         rs->sr_err = LDAP_NO_SUCH_OBJECT;
 559                 } else {
 560                         rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
 561                 }
 562
 563                 mdb_entry_return( op,e);
 564                 send_ldap_result( op, rs );
 565                 goto done;
 566         }
 567
 568         if ( !manageDSAit && is_entry_referral( e ) ) {
 569                 /* entry is a referral */
 570                 struct berval matched_dn = BER_BVNULL;
 571                 BerVarray erefs = NULL;
 572
 573                 ber_dupbv( &matched_dn, &e->e_name );
 574                 erefs = get_entry_referrals( op, e );
 575
 576                 rs->sr_err = LDAP_REFERRAL;
 577
 578                 mdb_entry_return( op, e );
 579                 e = NULL;
 580
 581                 if ( erefs ) {
 582                         rs->sr_ref = referral_rewrite( erefs, &matched_dn,
 583                                 &op->o_req_dn, op->oq_search.rs_scope );
 584                         ber_bvarray_free( erefs );
 585
 586                         if ( !rs->sr_ref ) {
 587                                 rs->sr_text = "bad_referral object";
 588                         }
 589                 }
 590
 591                 Debug( LDAP_DEBUG_TRACE,
 592                         LDAP_XSTRING(mdb_search) ": entry is referral\n",
 593                         0, 0, 0 );
 594
 595                 rs->sr_matched = matched_dn.bv_val;
 596                 send_ldap_result( op, rs );
 597
 598                 ber_bvarray_free( rs->sr_ref );
 599                 rs->sr_ref = NULL;
 600                 ber_memfree( matched_dn.bv_val );
 601                 rs->sr_matched = NULL;
 602                 goto done;
 603         }
 604
 605         if ( get_assert( op ) &&
 606                 ( test_filter( op, e, get_assertion( op )) != LDAP_COMPARE_TRUE ))
 607         {
 608                 rs->sr_err = LDAP_ASSERTION_FAILED;
 609                 mdb_entry_return( op,e);
 610                 send_ldap_result( op, rs );
 611                 goto done;
 612         }
 613
 614         /* compute it anyway; root does not use it */
 615         stoptime = op->o_time + op->ors_tlimit;
 616
 617         base = e;
 618
 619         e = NULL;
 620
 621         /* select candidates */
 622         if ( op->oq_search.rs_scope == LDAP_SCOPE_BASE ) {
 623                 rs->sr_err = base_candidate( op->o_bd, base, candidates );
 624                 scopes[0].mid = 0;
 625                 ncand = 1;
 626         } else {
 627                 if ( op->ors_scope == LDAP_SCOPE_ONELEVEL ) {
 628                         size_t nkids;
 629                         MDB_val key, data;
 630                         key.mv_data = &base->e_id;
 631                         key.mv_size = sizeof( ID );
 632                         mdb_cursor_get( mcd, &key, &data, MDB_SET );
 633                         mdb_cursor_count( mcd, &nkids );
 634                         nsubs = nkids - 1;
 635                 } else if ( !base->e_id ) {
 636                         /* we don't maintain nsubs for entryID 0.
 637                          * just grab entry count from id2entry stat
 638                          */
 639                         MDB_stat ms;
 640                         mdb_stat( ltid, mdb->mi_id2entry, &ms );
 641                         nsubs = ms.ms_entries;
 642                 }
 643                 MDB_IDL_ZERO( candidates );
 644                 scopes[0].mid = 1;
 645                 scopes[1].mid = base->e_id;
 646                 scopes[1].mval.mv_data = NULL;
 647                 rs->sr_err = search_candidates( op, rs, base,
 648                         &isc, mci, candidates, stack );
 649                 ncand = MDB_IDL_N( candidates );
 650                 if ( !base->e_id || ncand == NOID ) {
 651                         /* grab entry count from id2entry stat
 652                          */
 653                         MDB_stat ms;
 654                         mdb_stat( ltid, mdb->mi_id2entry, &ms );
 655                         if ( !base->e_id )
 656                                 nsubs = ms.ms_entries;
 657                         if ( ncand == NOID )
 658                                 ncand = ms.ms_entries;
 659                 }
 660         }
 661
 662         /* start cursor at beginning of candidates.
 663          */
 664         cursor = 0;
 665
 666         if ( candidates[0] == 0 ) {
 667                 Debug( LDAP_DEBUG_TRACE,
 668                         LDAP_XSTRING(mdb_search) ": no candidates\n",
 669                         0, 0, 0 );
 670
 671                 goto nochange;
 672         }
 673
 674         /* if not root and candidates exceed to-be-checked entries, abort */
 675         if ( op->ors_limit      /* isroot == FALSE */ &&
 676                 op->ors_limit->lms_s_unchecked != -1 &&
 677                 ncand > (unsigned) op->ors_limit->lms_s_unchecked )
 678         {
 679                 rs->sr_err = LDAP_ADMINLIMIT_EXCEEDED;
 680                 send_ldap_result( op, rs );
 681                 rs->sr_err = LDAP_SUCCESS;
 682                 goto done;
 683         }
 684
 685         if ( op->ors_limit == NULL      /* isroot == TRUE */ ||
 686                 !op->ors_limit->lms_s_pr_hide )
 687         {
 688                 tentries = ncand;
 689         }
 690
 691         wwctx.flag = 0;
 692         /* If we're running in our own read txn */
 693         if (  moi == &opinfo ) {
 694                 cb.sc_writewait = mdb_writewait;
 695                 cb.sc_private = &wwctx;
 696                 wwctx.txn = ltid;
 697                 wwctx.mcd = NULL;
 698                 cb.sc_next = op->o_callback;
 699                 op->o_callback = &cb;
 700         }
 701
 702         if ( get_pagedresults( op ) > SLAP_CONTROL_IGNORED ) {
 703                 PagedResultsState *ps = op->o_pagedresults_state;
 704                 /* deferred cookie parsing */
 705                 rs->sr_err = parse_paged_cookie( op, rs );
 706                 if ( rs->sr_err != LDAP_SUCCESS ) {
 707                         send_ldap_result( op, rs );
 708                         goto done;
 709                 }
 710
 711                 cursor = (ID) ps->ps_cookie;
 712                 if ( cursor && ps->ps_size == 0 ) {
 713                         rs->sr_err = LDAP_SUCCESS;
 714                         rs->sr_text = "search abandoned by pagedResult size=0";
 715                         send_ldap_result( op, rs );
 716                         goto done;
 717                 }
 718                 id = mdb_idl_first( candidates, &cursor );
 719                 if ( id == NOID ) {
 720                         Debug( LDAP_DEBUG_TRACE,
 721                                 LDAP_XSTRING(mdb_search)
 722                                 ": no paged results candidates\n",
 723                                 0, 0, 0 );
 724                         send_paged_response( op, rs, &lastid, 0 );
 725
 726                         rs->sr_err = LDAP_OTHER;
 727                         goto done;
 728                 }
 729                 if ( id == (ID)ps->ps_cookie )
 730                         id = mdb_idl_next( candidates, &cursor );
 731                 nsubs = ncand;  /* always bypass scope'd search */
 732                 goto loop_begin;
 733         }
 734         if ( nsubs < ncand ) {
 735                 int rc;
 736                 /* Do scope-based search */
 737
 738                 /* if any alias scopes were set, save them */
 739                 if (scopes[0].mid > 1) {
 740                         cursor = 1;
 741                         for (cscope = 1; cscope <= scopes[0].mid; cscope++) {
 742                                 /* Ignore the original base */
 743                                 if (scopes[cscope].mid == base->e_id)
 744                                         continue;
 745                                 iscopes[cursor++] = scopes[cscope].mid;
 746                         }
 747                         iscopes[0] = scopes[0].mid - 1;
 748                 } else {
 749                         iscopes[0] = 0;
 750                 }
 751
 752                 wwctx.mcd = mcd;
 753                 isc.id = base->e_id;
 754                 isc.numrdns = 0;
 755                 rc = mdb_dn2id_walk( op, &isc );
 756                 if ( rc )
 757                         id = NOID;
 758                 else
 759                         id = isc.id;
 760                 cscope = 0;
 761         } else {
 762                 id = mdb_idl_first( candidates, &cursor );
 763         }
 764
 765         while (id != NOID)
 766         {
 767                 int scopeok;
 768                 MDB_val edata;
 769
 770 loop_begin:
 771
 772                 /* check for abandon */
 773                 if ( op->o_abandon ) {
 774                         rs->sr_err = SLAPD_ABANDON;
 775                         send_ldap_result( op, rs );
 776                         goto done;
 777                 }
 778
 779                 /* mostly needed by internal searches,
 780                  * e.g. related to syncrepl, for whom
 781                  * abandon does not get set... */
 782                 if ( slapd_shutdown ) {
 783                         rs->sr_err = LDAP_UNAVAILABLE;
 784                         send_ldap_disconnect( op, rs );
 785                         goto done;
 786                 }
 787
 788                 /* check time limit */
 789                 if ( op->ors_tlimit != SLAP_NO_LIMIT
 790                                 && slap_get_time() > stoptime )
 791                 {
 792                         rs->sr_err = LDAP_TIMELIMIT_EXCEEDED;
 793                         rs->sr_ref = rs->sr_v2ref;
 794                         send_ldap_result( op, rs );
 795                         rs->sr_err = LDAP_SUCCESS;
 796                         goto done;
 797                 }
 798
 799
 800                 if ( nsubs < ncand ) {
 801                         unsigned i;
 802                         /* Is this entry in the candidate list? */
 803                         scopeok = 0;
 804                         if (MDB_IDL_IS_RANGE( candidates )) {
 805                                 if ( id >= MDB_IDL_RANGE_FIRST( candidates ) &&
 806                                         id <= MDB_IDL_RANGE_LAST( candidates ))
 807                                         scopeok = 1;
 808                         } else {
 809                                 i = mdb_idl_search( candidates, id );
 810                                 if ( candidates[i] == id )
 811                                         scopeok = 1;
 812                         }
 813                         if ( scopeok )
 814                                 goto scopeok;
 815                         goto loop_continue;
 816                 }
 817
 818                 /* Does this candidate actually satisfy the search scope?
 819                  */
 820                 scopeok = 0;
 821                 isc.numrdns = 0;
 822                 switch( op->ors_scope ) {
 823                 case LDAP_SCOPE_BASE:
 824                         /* This is always true, yes? */
 825                         if ( id == base->e_id ) scopeok = 1;
 826                         break;
 827
 828 #ifdef LDAP_SCOPE_CHILDREN
 829                 case LDAP_SCOPE_CHILDREN:
 830                         if ( id == base->e_id ) break;
 831                         /* Fall-thru */
 832 #endif
 833                 case LDAP_SCOPE_SUBTREE:
 834                         if ( id == base->e_id ) {
 835                                 scopeok = 1;
 836                                 break;
 837                         }
 838                         /* Fall-thru */
 839                 case LDAP_SCOPE_ONELEVEL:
 840                         isc.id = id;
 841                         isc.nscope = 0;
 842                         rs->sr_err = mdb_idscopes( op, &isc );
 843                         if ( rs->sr_err == MDB_SUCCESS ) {
 844                                 if ( isc.nscope )
 845                                         scopeok = 1;
 846                         } else {
 847                                 if ( rs->sr_err == MDB_NOTFOUND )
 848                                         goto notfound;
 849                         }
 850                         break;
 851                 }
 852
 853                 /* Not in scope, ignore it */
 854                 if ( !scopeok )
 855                 {
 856                         Debug( LDAP_DEBUG_TRACE,
 857                                 LDAP_XSTRING(mdb_search)
 858                                 ": %ld scope not okay\n",
 859                                 (long) id, 0, 0 );
 860                         goto loop_continue;
 861                 }
 862
 863 scopeok:
 864                 if ( id == base->e_id ) {
 865                         e = base;
 866                 } else {
 867
 868                         /* get the entry */
 869                         rs->sr_err = mdb_id2edata( op, mci, id, &edata );
 870                         if ( rs->sr_err == MDB_NOTFOUND ) {
 871 notfound:
 872                                 if( nsubs < ncand )
 873                                         goto loop_continue;
 874
 875                                 if( !MDB_IDL_IS_RANGE(candidates) ) {
 876                                         /* only complain for non-range IDLs */
 877                                         Debug( LDAP_DEBUG_TRACE,
 878                                                 LDAP_XSTRING(mdb_search)
 879                                                 ": candidate %ld not found\n",
 880                                                 (long) id, 0, 0 );
 881                                 } else {
 882                                         /* get the next ID from the DB */
 883                                         rs->sr_err = mdb_get_nextid( mci, &cursor );
 884                                         if ( rs->sr_err == MDB_NOTFOUND ) {
 885                                                 break;
 886                                         }
 887                                         if ( rs->sr_err ) {
 888                                                 rs->sr_err = LDAP_OTHER;
 889                                                 rs->sr_text = "internal error in get_nextid";
 890                                                 send_ldap_result( op, rs );
 891                                                 goto done;
 892                                         }
 893                                         cursor--;
 894                                 }
 895
 896                                 goto loop_continue;
 897                         } else if ( rs->sr_err ) {
 898                                 rs->sr_err = LDAP_OTHER;
 899                                 rs->sr_text = "internal error in mdb_id2edata";
 900                                 send_ldap_result( op, rs );
 901                                 goto done;
 902                         }
 903
 904                         rs->sr_err = mdb_entry_decode( op, ltid, &edata, &e );
 905                         if ( rs->sr_err ) {
 906                                 rs->sr_err = LDAP_OTHER;
 907                                 rs->sr_text = "internal error in mdb_entry_decode";
 908                                 send_ldap_result( op, rs );
 909                                 goto done;
 910                         }
 911                         e->e_id = id;
 912                         e->e_name.bv_val = NULL;
 913                         e->e_nname.bv_val = NULL;
 914                 }
 915
 916                 if ( is_entry_subentry( e ) ) {
 917                         if( op->oq_search.rs_scope != LDAP_SCOPE_BASE ) {
 918                                 if(!get_subentries_visibility( op )) {
 919                                         /* only subentries are visible */
 920                                         goto loop_continue;
 921                                 }
 922
 923                         } else if ( get_subentries( op ) &&
 924                                 !get_subentries_visibility( op ))
 925                         {
 926                                 /* only subentries are visible */
 927                                 goto loop_continue;
 928                         }
 929
 930                 } else if ( get_subentries_visibility( op )) {
 931                         /* only subentries are visible */
 932                         goto loop_continue;
 933                 }
 934
 935                 /* aliases were already dereferenced in candidate list */
 936                 if ( op->ors_deref & LDAP_DEREF_SEARCHING ) {
 937                         /* but if the search base is an alias, and we didn't
 938                          * deref it when finding, return it.
 939                          */
 940                         if ( is_entry_alias(e) &&
 941                                 ((op->ors_deref & LDAP_DEREF_FINDING) || e != base ))
 942                         {
 943                                 goto loop_continue;
 944                         }
 945                 }
 946
 947                 if ( !manageDSAit && is_entry_glue( e )) {
 948                         goto loop_continue;
 949                 }
 950
 951                 if (e != base) {
 952                         struct berval pdn, pndn;
 953                         char *d, *n;
 954                         int i;
 955
 956                         /* child of base, just append RDNs to base->e_name */
 957                         if ( nsubs < ncand || isc.scopes[isc.nscope].mid == base->e_id ) {
 958                                 pdn = base->e_name;
 959                                 pndn = base->e_nname;
 960                         } else {
 961                                 mdb_id2name( op, ltid, &isc.mc, scopes[isc.nscope].mid, &pdn, &pndn );
 962                         }
 963                         e->e_name.bv_len = pdn.bv_len;
 964                         e->e_nname.bv_len = pndn.bv_len;
 965                         for (i=0; i<isc.numrdns; i++) {
 966                                 e->e_name.bv_len += isc.rdns[i].bv_len + 1;
 967                                 e->e_nname.bv_len += isc.nrdns[i].bv_len + 1;
 968                         }
 969                         e->e_name.bv_val = op->o_tmpalloc(e->e_name.bv_len + 1, op->o_tmpmemctx);
 970                         e->e_nname.bv_val = op->o_tmpalloc(e->e_nname.bv_len + 1, op->o_tmpmemctx);
 971                         d = e->e_name.bv_val;
 972                         n = e->e_nname.bv_val;
 973                         if (nsubs < ncand) {
 974                                 /* RDNs are in top-down order */
 975                                 for (i=isc.numrdns-1; i>=0; i--) {
 976                                         memcpy(d, isc.rdns[i].bv_val, isc.rdns[i].bv_len);
 977                                         d += isc.rdns[i].bv_len;
 978                                         *d++ = ',';
 979                                         memcpy(n, isc.nrdns[i].bv_val, isc.nrdns[i].bv_len);
 980                                         n += isc.nrdns[i].bv_len;
 981                                         *n++ = ',';
 982                                 }
 983                         } else {
 984                                 /* RDNs are in bottom-up order */
 985                                 for (i=0; i<isc.numrdns; i++) {
 986                                         memcpy(d, isc.rdns[i].bv_val, isc.rdns[i].bv_len);
 987                                         d += isc.rdns[i].bv_len;
 988                                         *d++ = ',';
 989                                         memcpy(n, isc.nrdns[i].bv_val, isc.nrdns[i].bv_len);
 990                                         n += isc.nrdns[i].bv_len;
 991                                         *n++ = ',';
 992                                 }
 993                         }
 994
 995                         if (pdn.bv_len) {
 996                                 memcpy(d, pdn.bv_val, pdn.bv_len+1);
 997                                 memcpy(n, pndn.bv_val, pndn.bv_len+1);
 998                         } else {
 999                                 *--d = '\0';
1000                                 *--n = '\0';
1001                                 e->e_name.bv_len--;
1002                                 e->e_nname.bv_len--;
1003                         }
1004                         if (pndn.bv_val != base->e_nname.bv_val) {
1005                                 op->o_tmpfree(pndn.bv_val, op->o_tmpmemctx);
1006                                 op->o_tmpfree(pdn.bv_val, op->o_tmpmemctx);
1007                         }
1008                 }
1009
1010                 /*
1011                  * if it's a referral, add it to the list of referrals. only do
1012                  * this for non-base searches, and don't check the filter
1013                  * explicitly here since it's only a candidate anyway.
1014                  */
1015                 if ( !manageDSAit && op->oq_search.rs_scope != LDAP_SCOPE_BASE
1016                         && is_entry_referral( e ) )
1017                 {
1018                         BerVarray erefs = get_entry_referrals( op, e );
1019                         rs->sr_ref = referral_rewrite( erefs, &e->e_name, NULL,
1020                                 op->oq_search.rs_scope == LDAP_SCOPE_ONELEVEL
1021                                         ? LDAP_SCOPE_BASE : LDAP_SCOPE_SUBTREE );
1022
1023                         rs->sr_entry = e;
1024                         rs->sr_flags = 0;
1025
1026                         send_search_reference( op, rs );
1027
1028                         if (e != base)
1029                                 mdb_entry_return( op, e );
1030                         rs->sr_entry = NULL;
1031                         e = NULL;
1032
1033                         ber_bvarray_free( rs->sr_ref );
1034                         ber_bvarray_free( erefs );
1035                         rs->sr_ref = NULL;
1036
1037                         if ( wwctx.flag ) {
1038                                 rs->sr_err = mdb_waitfixup( op, &wwctx, mci, mcd );
1039                                 if ( rs->sr_err ) {
1040                                         send_ldap_result( op, rs );
1041                                         goto done;
1042                                 }
1043                         }
1044
1045                         goto loop_continue;
1046                 }
1047
1048                 /* if it matches the filter and scope, send it */
1049                 rs->sr_err = test_filter( op, e, op->oq_search.rs_filter );
1050
1051                 if ( rs->sr_err == LDAP_COMPARE_TRUE ) {
1052                         /* check size limit */
1053                         if ( get_pagedresults(op) > SLAP_CONTROL_IGNORED ) {
1054                                 if ( rs->sr_nentries >= ((PagedResultsState *)op->o_pagedresults_state)->ps_size ) {
1055                                         mdb_entry_return( op, e );
1056                                         e = NULL;
1057                                         send_paged_response( op, rs, &lastid, tentries );
1058                                         goto done;
1059                                 }
1060                                 lastid = id;
1061                         }
1062
1063                         if (e) {
1064                                 /* safe default */
1065                                 rs->sr_attrs = op->oq_search.rs_attrs;
1066                                 rs->sr_operational_attrs = NULL;
1067                                 rs->sr_ctrls = NULL;
1068                                 rs->sr_entry = e;
1069                                 RS_ASSERT( e->e_private != NULL );
1070                                 rs->sr_flags = 0;
1071                                 rs->sr_err = LDAP_SUCCESS;
1072                                 rs->sr_err = send_search_entry( op, rs );
1073                                 rs->sr_attrs = NULL;
1074                                 rs->sr_entry = NULL;
1075                                 if (e != base)
1076                                         mdb_entry_return( op, e );
1077                                 e = NULL;
1078
1079                                 switch ( rs->sr_err ) {
1080                                 case LDAP_SUCCESS:      /* entry sent ok */
1081                                         break;
1082                                 default:                /* entry not sent */
1083                                         break;
1084                                 case LDAP_BUSY:
1085                                         send_ldap_result( op, rs );
1086                                         goto done;
1087                                 case LDAP_UNAVAILABLE:
1088                                 case LDAP_SIZELIMIT_EXCEEDED:
1089                                         if ( rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ) {
1090                                                 rs->sr_ref = rs->sr_v2ref;
1091                                                 send_ldap_result( op, rs );
1092                                                 rs->sr_err = LDAP_SUCCESS;
1093
1094                                         } else {
1095                                                 rs->sr_err = LDAP_OTHER;
1096                                         }
1097                                         goto done;
1098                                 }
1099                                 if ( wwctx.flag ) {
1100                                         rs->sr_err = mdb_waitfixup( op, &wwctx, mci, mcd );
1101                                         if ( rs->sr_err ) {
1102                                                 send_ldap_result( op, rs );
1103                                                 goto done;
1104                                         }
1105                                 }
1106                         }
1107
1108                 } else {
1109                         Debug( LDAP_DEBUG_TRACE,
1110                                 LDAP_XSTRING(mdb_search)
1111                                 ": %ld does not match filter\n",
1112                                 (long) id, 0, 0 );
1113                 }
1114
1115 loop_continue:
1116                 if( e != NULL ) {
1117                         if ( e != base )
1118                                 mdb_entry_return( op, e );
1119                         RS_ASSERT( rs->sr_entry == NULL );
1120                         e = NULL;
1121                         rs->sr_entry = NULL;
1122                 }
1123
1124                 if ( nsubs < ncand ) {
1125                         int rc = mdb_dn2id_walk( op, &isc );
1126                         if (rc) {
1127                                 id = NOID;
1128                                 /* We got to the end of a subtree. If there are any
1129                                  * alias scopes left, search them too.
1130                                  */
1131                                 while (iscopes[0] && cscope < iscopes[0]) {
1132                                         cscope++;
1133                                         isc.id = iscopes[cscope];
1134                                         if ( base )
1135                                                 mdb_entry_return( op, base );
1136                                         rs->sr_err = mdb_id2entry(op, mci, isc.id, &base);
1137                                         if ( !rs->sr_err ) {
1138                                                 mdb_id2name( op, ltid, &isc.mc, isc.id, &base->e_name, &base->e_nname );
1139                                                 isc.numrdns = 0;
1140                                                 if (isc.oscope == LDAP_SCOPE_ONELEVEL)
1141                                                         isc.oscope = LDAP_SCOPE_BASE;
1142                                                 rc = mdb_dn2id_walk( op, &isc );
1143                                                 if ( !rc ) {
1144                                                         id = isc.id;
1145                                                         break;
1146                                                 }
1147                                         }
1148                                 }
1149                         } else
1150                                 id = isc.id;
1151                 } else {
1152                         id = mdb_idl_next( candidates, &cursor );
1153                 }
1154         }
1155
1156 nochange:
1157         rs->sr_ctrls = NULL;
1158         rs->sr_ref = rs->sr_v2ref;
1159         rs->sr_err = (rs->sr_v2ref == NULL) ? LDAP_SUCCESS : LDAP_REFERRAL;
1160         rs->sr_rspoid = NULL;
1161         if ( get_pagedresults(op) > SLAP_CONTROL_IGNORED ) {
1162                 send_paged_response( op, rs, NULL, 0 );
1163         } else {
1164                 send_ldap_result( op, rs );
1165         }
1166
1167         rs->sr_err = LDAP_SUCCESS;
1168
1169 done:
1170         if ( cb.sc_private ) {
1171                 /* remove our writewait callback */
1172                 slap_callback **scp = &op->o_callback;
1173                 while ( *scp ) {
1174                         if ( *scp == &cb ) {
1175                                 *scp = cb.sc_next;
1176                                 cb.sc_private = NULL;
1177                                 break;
1178                         }
1179                 }
1180         }
1181         mdb_cursor_close( mcd );
1182         mdb_cursor_close( mci );
1183         if ( moi == &opinfo ) {
1184                 mdb_txn_reset( moi->moi_txn );
1185                 LDAP_SLIST_REMOVE( &op->o_extra, &moi->moi_oe, OpExtra, oe_next );
1186         } else {
1187                 moi->moi_ref--;
1188         }
1189         if( rs->sr_v2ref ) {
1190                 ber_bvarray_free( rs->sr_v2ref );
1191                 rs->sr_v2ref = NULL;
1192         }
1193         if (base)
1194                 mdb_entry_return( op, base );
1195         scope_chunk_ret( op, scopes );
1196
1197         return rs->sr_err;
1198 }
1199
1200
1201 static int base_candidate(
1202         BackendDB       *be,
1203         Entry   *e,
1204         ID              *ids )
1205 {
1206         Debug(LDAP_DEBUG_ARGS, "base_candidates: base: \"%s\" (0x%08lx)\n",
1207                 e->e_nname.bv_val, (long) e->e_id, 0);
1208
1209         ids[0] = 1;
1210         ids[1] = e->e_id;
1211         return 0;
1212 }
1213
1214 /* Look for "objectClass Present" in this filter.
1215  * Also count depth of filter tree while we're at it.
1216  */
1217 static int oc_filter(
1218         Filter *f,
1219         int cur,
1220         int *max )
1221 {
1222         int rc = 0;
1223
1224         assert( f != NULL );
1225
1226         if( cur > *max ) *max = cur;
1227
1228         switch( f->f_choice ) {
1229         case LDAP_FILTER_PRESENT:
1230                 if (f->f_desc == slap_schema.si_ad_objectClass) {
1231                         rc = 1;
1232                 }
1233                 break;
1234
1235         case LDAP_FILTER_AND:
1236         case LDAP_FILTER_OR:
1237                 cur++;
1238                 for ( f=f->f_and; f; f=f->f_next ) {
1239                         (void) oc_filter(f, cur, max);
1240                 }
1241                 break;
1242
1243         default:
1244                 break;
1245         }
1246         return rc;
1247 }
1248
1249 static void search_stack_free( void *key, void *data )
1250 {
1251         ber_memfree_x(data, NULL);
1252 }
1253
1254 static void *search_stack( Operation *op )
1255 {
1256         struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
1257         void *ret = NULL;
1258
1259         if ( op->o_threadctx ) {
1260                 ldap_pvt_thread_pool_getkey( op->o_threadctx, (void *)search_stack,
1261                         &ret, NULL );
1262         } else {
1263                 ret = mdb->mi_search_stack;
1264         }
1265
1266         if ( !ret ) {
1267                 ret = ch_malloc( mdb->mi_search_stack_depth * MDB_IDL_UM_SIZE
1268                         * sizeof( ID ) );
1269                 if ( op->o_threadctx ) {
1270                         ldap_pvt_thread_pool_setkey( op->o_threadctx, (void *)search_stack,
1271                                 ret, search_stack_free, NULL, NULL );
1272                 } else {
1273                         mdb->mi_search_stack = ret;
1274                 }
1275         }
1276         return ret;
1277 }
1278
1279 static int search_candidates(
1280         Operation *op,
1281         SlapReply *rs,
1282         Entry *e,
1283         IdScopes *isc,
1284         MDB_cursor *mci,
1285         ID      *ids,
1286         ID *stack )
1287 {
1288         struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
1289         int rc, depth = 1;
1290         Filter          *f, rf, xf, nf, sf;
1291         AttributeAssertion aa_ref = ATTRIBUTEASSERTION_INIT;
1292         AttributeAssertion aa_subentry = ATTRIBUTEASSERTION_INIT;
1293
1294         /*
1295          * This routine takes as input a filter (user-filter)
1296          * and rewrites it as follows:
1297          *      (&(scope=DN)[(objectClass=subentry)]
1298          *              (|[(objectClass=referral)](user-filter))
1299          */
1300
1301         Debug(LDAP_DEBUG_TRACE,
1302                 "search_candidates: base=\"%s\" (0x%08lx) scope=%d\n",
1303                 e->e_nname.bv_val, (long) e->e_id, op->oq_search.rs_scope );
1304
1305         f = op->oq_search.rs_filter;
1306
1307         /* If the user's filter uses objectClass=*,
1308          * these clauses are redundant.
1309          */
1310         if (!oc_filter(op->oq_search.rs_filter, 1, &depth)
1311                 && !get_subentries_visibility(op)) {
1312                 if( !get_manageDSAit(op) && !get_domainScope(op) ) {
1313                         /* match referral objects */
1314                         struct berval bv_ref = BER_BVC( "referral" );
1315                         rf.f_choice = LDAP_FILTER_EQUALITY;
1316                         rf.f_ava = &aa_ref;
1317                         rf.f_av_desc = slap_schema.si_ad_objectClass;
1318                         rf.f_av_value = bv_ref;
1319                         rf.f_next = f;
1320                         xf.f_or = &rf;
1321                         xf.f_choice = LDAP_FILTER_OR;
1322                         xf.f_next = NULL;
1323                         f = &xf;
1324                         depth++;
1325                 }
1326         }
1327
1328         if( get_subentries_visibility( op ) ) {
1329                 struct berval bv_subentry = BER_BVC( "subentry" );
1330                 sf.f_choice = LDAP_FILTER_EQUALITY;
1331                 sf.f_ava = &aa_subentry;
1332                 sf.f_av_desc = slap_schema.si_ad_objectClass;
1333                 sf.f_av_value = bv_subentry;
1334                 sf.f_next = f;
1335                 nf.f_choice = LDAP_FILTER_AND;
1336                 nf.f_and = &sf;
1337                 nf.f_next = NULL;
1338                 f = &nf;
1339                 depth++;
1340         }
1341
1342         /* Allocate IDL stack, plus 1 more for former tmp */
1343         if ( depth+1 > mdb->mi_search_stack_depth ) {
1344                 stack = ch_malloc( (depth + 1) * MDB_IDL_UM_SIZE * sizeof( ID ) );
1345         }
1346
1347         if( op->ors_deref & LDAP_DEREF_SEARCHING ) {
1348                 rc = search_aliases( op, rs, e->e_id, isc, mci, stack );
1349         } else {
1350                 rc = LDAP_SUCCESS;
1351         }
1352
1353         if ( rc == LDAP_SUCCESS ) {
1354                 rc = mdb_filter_candidates( op, isc->mt, f, ids,
1355                         stack, stack+MDB_IDL_UM_SIZE );
1356         }
1357
1358         if ( depth+1 > mdb->mi_search_stack_depth ) {
1359                 ch_free( stack );
1360         }
1361
1362         if( rc ) {
1363                 Debug(LDAP_DEBUG_TRACE,
1364                         "mdb_search_candidates: failed (rc=%d)\n",
1365                         rc, NULL, NULL );
1366
1367         } else {
1368                 Debug(LDAP_DEBUG_TRACE,
1369                         "mdb_search_candidates: id=%ld first=%ld last=%ld\n",
1370                         (long) ids[0],
1371                         (long) MDB_IDL_FIRST(ids),
1372                         (long) MDB_IDL_LAST(ids) );
1373         }
1374
1375         return rc;
1376 }
1377
1378 static int
1379 parse_paged_cookie( Operation *op, SlapReply *rs )
1380 {
1381         int             rc = LDAP_SUCCESS;
1382         PagedResultsState *ps = op->o_pagedresults_state;
1383
1384         /* this function must be invoked only if the pagedResults
1385          * control has been detected, parsed and partially checked
1386          * by the frontend */
1387         assert( get_pagedresults( op ) > SLAP_CONTROL_IGNORED );
1388
1389         /* cookie decoding/checks deferred to backend... */
1390         if ( ps->ps_cookieval.bv_len ) {
1391                 PagedResultsCookie reqcookie;
1392                 if( ps->ps_cookieval.bv_len != sizeof( reqcookie ) ) {
1393                         /* bad cookie */
1394                         rs->sr_text = "paged results cookie is invalid";
1395                         rc = LDAP_PROTOCOL_ERROR;
1396                         goto done;
1397                 }
1398
1399                 AC_MEMCPY( &reqcookie, ps->ps_cookieval.bv_val, sizeof( reqcookie ));
1400
1401                 if ( reqcookie > ps->ps_cookie ) {
1402                         /* bad cookie */
1403                         rs->sr_text = "paged results cookie is invalid";
1404                         rc = LDAP_PROTOCOL_ERROR;
1405                         goto done;
1406
1407                 } else if ( reqcookie < ps->ps_cookie ) {
1408                         rs->sr_text = "paged results cookie is invalid or old";
1409                         rc = LDAP_UNWILLING_TO_PERFORM;
1410                         goto done;
1411                 }
1412
1413         } else {
1414                 /* we're going to use ps_cookie */
1415                 op->o_conn->c_pagedresults_state.ps_cookie = 0;
1416         }
1417
1418 done:;
1419
1420         return rc;
1421 }
1422
1423 static void
1424 send_paged_response(
1425         Operation       *op,
1426         SlapReply       *rs,
1427         ID              *lastid,
1428         int             tentries )
1429 {
1430         LDAPControl     *ctrls[2];
1431         BerElementBuffer berbuf;
1432         BerElement      *ber = (BerElement *)&berbuf;
1433         PagedResultsCookie respcookie;
1434         struct berval cookie;
1435
1436         Debug(LDAP_DEBUG_ARGS,
1437                 "send_paged_response: lastid=0x%08lx nentries=%d\n",
1438                 lastid ? *lastid : 0, rs->sr_nentries, NULL );
1439
1440         ctrls[1] = NULL;
1441
1442         ber_init2( ber, NULL, LBER_USE_DER );
1443
1444         if ( lastid ) {
1445                 respcookie = ( PagedResultsCookie )(*lastid);
1446                 cookie.bv_len = sizeof( respcookie );
1447                 cookie.bv_val = (char *)&respcookie;
1448
1449         } else {
1450                 respcookie = ( PagedResultsCookie )0;
1451                 BER_BVSTR( &cookie, "" );
1452         }
1453
1454         op->o_conn->c_pagedresults_state.ps_cookie = respcookie;
1455         op->o_conn->c_pagedresults_state.ps_count =
1456                 ((PagedResultsState *)op->o_pagedresults_state)->ps_count +
1457                 rs->sr_nentries;
1458
1459         /* return size of 0 -- no estimate */
1460         ber_printf( ber, "{iO}", 0, &cookie );
1461
1462         ctrls[0] = op->o_tmpalloc( sizeof(LDAPControl), op->o_tmpmemctx );
1463         if ( ber_flatten2( ber, &ctrls[0]->ldctl_value, 0 ) == -1 ) {
1464                 goto done;
1465         }
1466
1467         ctrls[0]->ldctl_oid = LDAP_CONTROL_PAGEDRESULTS;
1468         ctrls[0]->ldctl_iscritical = 0;
1469
1470         slap_add_ctrls( op, rs, ctrls );
1471         rs->sr_err = LDAP_SUCCESS;
1472         send_ldap_result( op, rs );
1473
1474 done:
1475         (void) ber_free_buf( ber );
1476 }