]> git.sur5r.net Git - openldap/blobdiff - servers/slapd/back-bdb/search.c
import fix to ITS#5172
[openldap] / servers / slapd / back-bdb / search.c
index ec841d7597dbff92908b21a3e5af6e0eddc6748a..520d44a5c4e0cf3f0fcd6089442aedf4db301456 100644 (file)
@@ -1,8 +1,17 @@
 /* search.c - search operation */
 /* $OpenLDAP$ */
-/*
- * Copyright 1998-2002 The OpenLDAP Foundation, All Rights Reserved.
- * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2000-2007 The OpenLDAP Foundation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
  */
 
 #include "portable.h"
 
 #include "back-bdb.h"
 #include "idl.h"
-#include "external.h"
 
 static int base_candidate(
        BackendDB       *be,
        Entry   *e,
        ID              *ids );
+
 static int search_candidates(
-       BackendDB *be,
        Operation *op,
+       SlapReply *rs,
+       Entry *e,
+       u_int32_t locker,
+       ID      *ids,
+       ID      *scopes );
+
+static int parse_paged_cookie( Operation *op, SlapReply *rs );
+
+static void send_paged_response( 
+       Operation *op,
+       SlapReply *rs,
+       ID  *lastid,
+       int tentries );
+
+/* Dereference aliases for a single alias entry. Return the final
+ * dereferenced entry on success, NULL on any failure.
+ */
+static Entry * deref_base (
+       Operation *op,
+       SlapReply *rs,
        Entry *e,
-       Filter *filter,
-       int scope,
-       int deref,
-       ID      *ids );
+       Entry **matched,
+       u_int32_t locker,
+       DB_LOCK *lock,
+       ID      *tmp,
+       ID      *visited )
+{
+       struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
+       struct berval ndn;
+       EntryInfo *ei;
+       DB_LOCK lockr;
+
+       rs->sr_err = LDAP_ALIAS_DEREF_PROBLEM;
+       rs->sr_text = "maximum deref depth exceeded";
+
+       for (;;) {
+               /* Remember the last entry we looked at, so we can
+                * report broken links
+                */
+               *matched = e;
+
+               if (BDB_IDL_N(tmp) >= op->o_bd->be_max_deref_depth) {
+                       e = NULL;
+                       break;
+               }
+
+               /* If this is part of a subtree or onelevel search,
+                * have we seen this ID before? If so, quit.
+                */
+               if ( visited && bdb_idl_insert( visited, e->e_id ) ) {
+                       e = NULL;
+                       break;
+               }
+
+               /* If we've seen this ID during this deref iteration,
+                * we've hit a loop.
+                */
+               if ( bdb_idl_insert( tmp, e->e_id ) ) {
+                       rs->sr_err = LDAP_ALIAS_PROBLEM;
+                       rs->sr_text = "circular alias";
+                       e = NULL;
+                       break;
+               }
+
+               /* If there was a problem getting the aliasedObjectName,
+                * get_alias_dn will have set the error status.
+                */
+               if ( get_alias_dn(e, &ndn, &rs->sr_err, &rs->sr_text) ) {
+                       e = NULL;
+                       break;
+               }
+
+               rs->sr_err = bdb_dn2entry( op, NULL, &ndn, &ei,
+                       0, locker, &lockr );
+
+               if ( ei ) {
+                       e = ei->bei_e;
+               } else {
+                       e = NULL;
+               }
+
+               if (!e) {
+                       rs->sr_err = LDAP_ALIAS_PROBLEM;
+                       rs->sr_text = "aliasedObject not found";
+                       break;
+               }
+
+               /* Free the previous entry, continue to work with the
+                * one we just retrieved.
+                */
+               bdb_cache_return_entry_r( bdb->bi_dbenv, &bdb->bi_cache,
+                       *matched, lock);
+               *lock = lockr;
+
+               /* We found a regular entry. Return this to the caller. The
+                * entry is still locked for Read.
+                */
+               if (!is_entry_alias(e)) {
+                       rs->sr_err = LDAP_SUCCESS;
+                       rs->sr_text = NULL;
+                       break;
+               }
+       }
+       return e;
+}
+
+/* Look for and dereference all aliases within the search scope. Adds
+ * the dereferenced entries to the "ids" list. Requires "stack" to be
+ * able to hold 8 levels of DB_SIZE IDLs. Of course we're hardcoded to
+ * require a minimum of 8 UM_SIZE IDLs so this is never a problem.
+ */
+static int search_aliases(
+       Operation *op,
+       SlapReply *rs,
+       Entry *e,
+       u_int32_t locker,
+       ID *ids,
+       ID *scopes,
+       ID *stack )
+{
+       struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
+       ID *aliases, *curscop, *subscop, *visited, *newsubs, *oldsubs, *tmp;
+       ID cursora, ida, cursoro, ido, *subscop2;
+       Entry *matched, *a;
+       EntryInfo *ei;
+       struct berval bv_alias = BER_BVC( "alias" );
+#ifdef LDAP_COMP_MATCH
+       AttributeAssertion aa_alias = { NULL, BER_BVNULL, NULL };
+#else
+       AttributeAssertion aa_alias = { NULL, BER_BVNULL };
+#endif
+       Filter  af;
+       DB_LOCK locka, lockr;
+       int first = 1;
+
+       aliases = stack;        /* IDL of all aliases in the database */
+       curscop = aliases + BDB_IDL_DB_SIZE;    /* Aliases in the current scope */
+       subscop = curscop + BDB_IDL_DB_SIZE;    /* The current scope */
+       visited = subscop + BDB_IDL_DB_SIZE;    /* IDs we've seen in this search */
+       newsubs = visited + BDB_IDL_DB_SIZE;    /* New subtrees we've added */
+       oldsubs = newsubs + BDB_IDL_DB_SIZE;    /* Subtrees added previously */
+       tmp = oldsubs + BDB_IDL_DB_SIZE;        /* Scratch space for deref_base() */
+
+       /* A copy of subscop, because subscop gets clobbered by
+        * the bdb_idl_union/intersection routines
+        */
+       subscop2 = tmp + BDB_IDL_DB_SIZE;
+
+       af.f_choice = LDAP_FILTER_EQUALITY;
+       af.f_ava = &aa_alias;
+       af.f_av_desc = slap_schema.si_ad_objectClass;
+       af.f_av_value = bv_alias;
+       af.f_next = NULL;
+
+       /* Find all aliases in database */
+       BDB_IDL_ZERO( aliases );
+       rs->sr_err = bdb_filter_candidates( op, &af, aliases,
+               curscop, visited );
+       if (rs->sr_err != LDAP_SUCCESS) {
+               return rs->sr_err;
+       }
+       oldsubs[0] = 1;
+       oldsubs[1] = e->e_id;
+
+       BDB_IDL_ZERO( ids );
+       BDB_IDL_ZERO( visited );
+       BDB_IDL_ZERO( newsubs );
+
+       cursoro = 0;
+       ido = bdb_idl_first( oldsubs, &cursoro );
+
+       for (;;) {
+               /* Set curscop to only the aliases in the current scope. Start with
+                * all the aliases, obtain the IDL for the current scope, and then
+                * get the intersection of these two IDLs. Add the current scope
+                * to the cumulative list of candidates.
+                */
+               BDB_IDL_CPY( curscop, aliases );
+               rs->sr_err = bdb_dn2idl( op, e, subscop,
+                       subscop2+BDB_IDL_DB_SIZE );
+               if (first) {
+                       first = 0;
+               } else {
+                       bdb_cache_return_entry_r (bdb->bi_dbenv, &bdb->bi_cache, e, &locka);
+               }
+               BDB_IDL_CPY(subscop2, subscop);
+               rs->sr_err = bdb_idl_intersection(curscop, subscop);
+               bdb_idl_union( ids, subscop2 );
+
+               /* Dereference all of the aliases in the current scope. */
+               cursora = 0;
+               for (ida = bdb_idl_first(curscop, &cursora); ida != NOID;
+                       ida = bdb_idl_next(curscop, &cursora))
+               {
+                       ei = NULL;
+retry1:
+                       rs->sr_err = bdb_cache_find_id(op, NULL,
+                               ida, &ei, 0, locker, &lockr );
+                       if (rs->sr_err != LDAP_SUCCESS) {
+                               if ( rs->sr_err == DB_LOCK_DEADLOCK ||
+                                       rs->sr_err == DB_LOCK_NOTGRANTED ) goto retry1;
+                               continue;
+                       }
+                       a = ei->bei_e;
+
+                       /* This should only happen if the curscop IDL has maxed out and
+                        * turned into a range that spans IDs indiscriminately
+                        */
+                       if (!is_entry_alias(a)) {
+                               bdb_cache_return_entry_r (bdb->bi_dbenv, &bdb->bi_cache,
+                                       a, &lockr);
+                               continue;
+                       }
+
+                       /* Actually dereference the alias */
+                       BDB_IDL_ZERO(tmp);
+                       a = deref_base( op, rs, a, &matched, locker, &lockr,
+                               tmp, visited );
+                       if (a) {
+                               /* If the target was not already in our current candidates,
+                                * make note of it in the newsubs list. Also
+                                * set it in the scopes list so that bdb_search
+                                * can check it.
+                                */
+                               if (bdb_idl_insert(ids, a->e_id) == 0) {
+                                       bdb_idl_insert(newsubs, a->e_id);
+                                       bdb_idl_insert(scopes, a->e_id);
+                               }
+                               bdb_cache_return_entry_r( bdb->bi_dbenv, &bdb->bi_cache,
+                                       a, &lockr);
+
+                       } else if (matched) {
+                               /* Alias could not be dereferenced, or it deref'd to
+                                * an ID we've already seen. Ignore it.
+                                */
+                               bdb_cache_return_entry_r( bdb->bi_dbenv, &bdb->bi_cache,
+                                       matched, &lockr );
+                               rs->sr_text = NULL;
+                       }
+               }
+               /* If this is a OneLevel search, we're done; oldsubs only had one
+                * ID in it. For a Subtree search, oldsubs may be a list of scope IDs.
+                */
+               if ( op->ors_scope == LDAP_SCOPE_ONELEVEL ) break;
+nextido:
+               ido = bdb_idl_next( oldsubs, &cursoro );
+               
+               /* If we're done processing the old scopes, did we add any new
+                * scopes in this iteration? If so, go back and do those now.
+                */
+               if (ido == NOID) {
+                       if (BDB_IDL_IS_ZERO(newsubs)) break;
+                       BDB_IDL_CPY(oldsubs, newsubs);
+                       BDB_IDL_ZERO(newsubs);
+                       cursoro = 0;
+                       ido = bdb_idl_first( oldsubs, &cursoro );
+               }
+
+               /* Find the entry corresponding to the next scope. If it can't
+                * be found, ignore it and move on. This should never happen;
+                * we should never see the ID of an entry that doesn't exist.
+                * Set the name so that the scope's IDL can be retrieved.
+                */
+               ei = NULL;
+sameido:
+               rs->sr_err = bdb_cache_find_id(op, NULL, ido, &ei,
+                       0, locker, &locka );
+               if ( rs->sr_err != LDAP_SUCCESS ) {
+                       if ( rs->sr_err == DB_LOCK_DEADLOCK ||
+                               rs->sr_err == DB_LOCK_NOTGRANTED )
+                               goto sameido;
+                       goto nextido;
+               }
+               e = ei->bei_e;
+       }
+       return rs->sr_err;
+}
 
 int
-bdb_search(
-       BackendDB       *be,
-       Connection      *conn,
-       Operation       *op,
-       struct berval   *base,
-       struct berval   *nbase,
-       int             scope,
-       int             deref,
-       int             slimit,
-       int             tlimit,
-       Filter  *filter,
-       struct berval   *filterstr,
-       AttributeName   *attrs,
-       int             attrsonly )
+bdb_search( Operation *op, SlapReply *rs )
 {
-       struct bdb_info *bdb = (struct bdb_info *) be->be_private;
-       int              abandon;
-       int             rc;
-       const char *text = NULL;
+       struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
        time_t          stoptime;
        ID              id, cursor;
        ID              candidates[BDB_IDL_UM_SIZE];
-       Entry           *e = NULL;
-       BerVarray v2refs = NULL;
-       Entry   *matched = NULL;
-       struct berval   realbase = { 0, NULL };
-       int             nentries = 0;
+       ID              scopes[BDB_IDL_DB_SIZE];
+       Entry           *e = NULL, base, e_root = {0};
+       Entry           *matched = NULL;
+       EntryInfo       *ei, ei_root = {0};
+       struct berval   realbase = BER_BVNULL;
+#ifdef SLAP_ACL_HONOR_DISCLOSE
+       slap_mask_t     mask;
+#endif
        int             manageDSAit;
+       int             tentries = 0;
+       ID              lastid = NOID;
+       AttributeName   *attrs;
 
-       struct slap_limits_set *limit = NULL;
-       int isroot = 0;
+       u_int32_t       locker = 0;
+       DB_LOCK         lock;
+       struct  bdb_op_info     *opinfo = NULL;
+       DB_TXN                  *ltid = NULL;
 
-       Debug( LDAP_DEBUG_TRACE, "=> bdb_back_search\n",
-               0, 0, 0);
+       Debug( LDAP_DEBUG_TRACE, "=> " LDAP_XSTRING(bdb_search) "\n", 0, 0, 0);
+       attrs = op->oq_search.rs_attrs;
+
+       opinfo = (struct bdb_op_info *) op->o_private;
 
        manageDSAit = get_manageDSAit( op );
 
-       if ( nbase->bv_len == 0 ) {
+       if ( opinfo && opinfo->boi_txn ) {
+               ltid = opinfo->boi_txn;
+               locker = TXN_ID( ltid );
+       } else {
+               rs->sr_err = LOCK_ID( bdb->bi_dbenv, &locker );
+
+               switch(rs->sr_err) {
+               case 0:
+                       break;
+               default:
+                       send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
+                       return rs->sr_err;
+               }
+       }
+
+       if ( op->o_req_ndn.bv_len == 0 ) {
                /* DIT root special case */
-               e = (Entry *) &slap_entry_root;
-               rc = 0;
-       } else                                          
-#ifdef BDB_ALIASES
-       /* get entry with reader lock */
-       if ( deref & LDAP_DEREF_FINDING ) {
-               e = deref_dn_r( be, nbase-, &err, &matched, &text );
-
-       } else
-#endif
-       {
-               rc = bdb_dn2entry( be, NULL, nbase, &e, &matched, 0 );
+               ei_root.bei_e = &e_root;
+               ei_root.bei_parent = &ei_root;
+               e_root.e_private = &ei_root;
+               e_root.e_id = 0;
+               e_root.e_ocflags = SLAP_OC_GLUE | SLAP_OC__END;
+               BER_BVSTR( &e_root.e_nname, "" );
+               BER_BVSTR( &e_root.e_name, "" );
+               ei = &ei_root;
+               rs->sr_err = LDAP_SUCCESS;
+       } else {
+               if ( op->ors_deref & LDAP_DEREF_FINDING ) {
+                       BDB_IDL_ZERO(candidates);
+               }
+dn2entry_retry:
+               /* get entry with reader lock */
+               rs->sr_err = bdb_dn2entry( op, ltid, &op->o_req_ndn, &ei,
+                       1, locker, &lock );
        }
 
-       switch(rc) {
+       switch(rs->sr_err) {
        case DB_NOTFOUND:
+               matched = ei->bei_e;
+               break;
        case 0:
+               e = ei->bei_e;
                break;
+       case LDAP_BUSY:
+               send_ldap_error( op, rs, LDAP_BUSY, "ldap server busy" );
+               if ( !opinfo )
+                       LOCK_ID_FREE (bdb->bi_dbenv, locker );
+               return LDAP_BUSY;
+       case DB_LOCK_DEADLOCK:
+       case DB_LOCK_NOTGRANTED:
+               goto dn2entry_retry;
        default:
-               send_ldap_result( conn, op, rc=LDAP_OTHER,
-                       NULL, "internal error", NULL, NULL );
-               return rc;
+               send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
+               if ( !opinfo )
+                       LOCK_ID_FREE (bdb->bi_dbenv, locker );
+               return rs->sr_err;
+       }
+
+       if ( op->ors_deref & LDAP_DEREF_FINDING ) {
+               if ( matched && is_entry_alias( matched )) {
+                       struct berval stub;
+
+                       stub.bv_val = op->o_req_ndn.bv_val;
+                       stub.bv_len = op->o_req_ndn.bv_len - matched->e_nname.bv_len - 1;
+                       e = deref_base( op, rs, matched, &matched, locker, &lock,
+                               candidates, NULL );
+                       if ( e ) {
+                               build_new_dn( &op->o_req_ndn, &e->e_nname, &stub,
+                                       op->o_tmpmemctx );
+                               bdb_cache_return_entry_r (bdb->bi_dbenv, &bdb->bi_cache,
+                                       e, &lock);
+                               matched = NULL;
+                               goto dn2entry_retry;
+                       }
+               } else if ( e && is_entry_alias( e )) {
+                       e = deref_base( op, rs, e, &matched, locker, &lock,
+                               candidates, NULL );
+               }
        }
 
        if ( e == NULL ) {
-               struct berval matched_dn = { 0, NULL };
-               BerVarray refs = NULL;
+               struct berval matched_dn = BER_BVNULL;
 
                if ( matched != NULL ) {
-                       BerVarray erefs;
-
-                       ber_dupbv( &matched_dn, &matched->e_name );
+                       BerVarray erefs = NULL;
+
+#ifdef SLAP_ACL_HONOR_DISCLOSE
+                       /* return referral only if "disclose"
+                        * is granted on the object */
+                       if ( ! access_allowed( op, matched,
+                                               slap_schema.si_ad_entry,
+                                               NULL, ACL_DISCLOSE, NULL ) )
+                       {
+                               rs->sr_err = LDAP_NO_SUCH_OBJECT;
 
-                       erefs = is_entry_referral( matched )
-                               ? get_entry_referrals( be, conn, op, matched )
-                               : NULL;
+                       } else
+#endif /* SLAP_ACL_HONOR_DISCLOSE */
+                       {
+                               ber_dupbv( &matched_dn, &matched->e_name );
+
+                               erefs = is_entry_referral( matched )
+                                       ? get_entry_referrals( op, matched )
+                                       : NULL;
+                               if ( rs->sr_err == DB_NOTFOUND )
+                                       rs->sr_err = LDAP_REFERRAL;
+                               rs->sr_matched = matched_dn.bv_val;
+                       }
 
-                       bdb_entry_return( be, matched );
+#ifdef SLAP_ZONE_ALLOC
+                       slap_zn_runlock(bdb->bi_cache.c_zctx, matched);
+#endif
+                       bdb_cache_return_entry_r (bdb->bi_dbenv, &bdb->bi_cache,
+                               matched, &lock);
                        matched = NULL;
 
-                       if( erefs ) {
-                               refs = referral_rewrite( erefs, &matched_dn,
-                                       base, scope );
+                       if ( erefs ) {
+                               rs->sr_ref = referral_rewrite( erefs, &matched_dn,
+                                       &op->o_req_dn, op->oq_search.rs_scope );
                                ber_bvarray_free( erefs );
                        }
 
                } else {
-                       refs = referral_rewrite( default_referral,
-                               NULL, base, scope );
+#ifdef SLAP_ZONE_ALLOC
+                       slap_zn_runlock(bdb->bi_cache.c_zctx, matched);
+#endif
+                       rs->sr_ref = referral_rewrite( default_referral,
+                               NULL, &op->o_req_dn, op->oq_search.rs_scope );
+                       rs->sr_err = rs->sr_ref != NULL ? LDAP_REFERRAL : LDAP_NO_SUCH_OBJECT;
                }
 
-               send_ldap_result( conn, op,     rc=LDAP_REFERRAL ,
-                       matched_dn.bv_val, text, refs, NULL );
+               send_ldap_result( op, rs );
 
-               if ( refs ) ber_bvarray_free( refs );
-               if ( matched_dn.bv_val ) ber_memfree( matched_dn.bv_val );
-               return rc;
+               if ( !opinfo )
+                       LOCK_ID_FREE (bdb->bi_dbenv, locker );
+               if ( rs->sr_ref ) {
+                       ber_bvarray_free( rs->sr_ref );
+                       rs->sr_ref = NULL;
+               }
+               if ( !BER_BVISNULL( &matched_dn ) ) {
+                       ber_memfree( matched_dn.bv_val );
+                       rs->sr_matched = NULL;
+               }
+               return rs->sr_err;
        }
 
-       if (!manageDSAit && e != &slap_entry_root && is_entry_referral( e ) ) {
+#ifdef SLAP_ACL_HONOR_DISCLOSE
+       /* NOTE: __NEW__ "search" access is required
+        * on searchBase object */
+       if ( ! access_allowed_mask( op, e, slap_schema.si_ad_entry,
+                               NULL, ACL_SEARCH, NULL, &mask ) )
+       {
+               if ( !ACL_GRANT( mask, ACL_DISCLOSE ) ) {
+                       rs->sr_err = LDAP_NO_SUCH_OBJECT;
+               } else {
+                       rs->sr_err = LDAP_INSUFFICIENT_ACCESS;
+               }
+
+#ifdef SLAP_ZONE_ALLOC
+               slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+               if ( e != &e_root ) {
+                       bdb_cache_return_entry_r(bdb->bi_dbenv, &bdb->bi_cache, e, &lock);
+               }
+               send_ldap_result( op, rs );
+               return rs->sr_err;
+       }
+#endif /* SLAP_ACL_HONOR_DISCLOSE */
+
+       if ( !manageDSAit && e != &e_root && is_entry_referral( e ) ) {
                /* entry is a referral, don't allow add */
-               struct berval matched_dn;
-               BerVarray erefs, refs;
+               struct berval matched_dn = BER_BVNULL;
+               BerVarray erefs = NULL;
                
                ber_dupbv( &matched_dn, &e->e_name );
-               erefs = get_entry_referrals( be, conn, op, e );
-               refs = NULL;
+               erefs = get_entry_referrals( op, e );
+
+               rs->sr_err = LDAP_REFERRAL;
 
-               bdb_entry_return( be, e );
+#ifdef SLAP_ZONE_ALLOC
+               slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+               bdb_cache_return_entry_r( bdb->bi_dbenv, &bdb->bi_cache, e, &lock );
                e = NULL;
 
-               if( erefs ) {
-                       refs = referral_rewrite( erefs, &matched_dn,
-                               base, scope );
+               if ( erefs ) {
+                       rs->sr_ref = referral_rewrite( erefs, &matched_dn,
+                               &op->o_req_dn, op->oq_search.rs_scope );
                        ber_bvarray_free( erefs );
+
+                       if ( !rs->sr_ref ) {
+                               rs->sr_text = "bad_referral object";
+                       }
                }
 
-               Debug( LDAP_DEBUG_TRACE, "bdb_search: entry is referral\n",
+               Debug( LDAP_DEBUG_TRACE,
+                       LDAP_XSTRING(bdb_search) ": entry is referral\n",
                        0, 0, 0 );
 
-               send_ldap_result( conn, op, LDAP_REFERRAL,
-                       matched_dn.bv_val,
-                       refs ? NULL : "bad referral object",
-                       refs, NULL );
+               rs->sr_matched = matched_dn.bv_val;
+               send_ldap_result( op, rs );
 
-               ber_bvarray_free( refs );
+               if ( !opinfo ) {
+                       LOCK_ID_FREE (bdb->bi_dbenv, locker );
+               }
+               ber_bvarray_free( rs->sr_ref );
+               rs->sr_ref = NULL;
                ber_memfree( matched_dn.bv_val );
+               rs->sr_matched = NULL;
                return 1;
        }
 
-       /* if not root, get appropriate limits */
-       if ( be_isroot( be, &op->o_ndn ) ) {
-               isroot = 1;
-       } else {
-               ( void ) get_limits( be, &op->o_ndn, &limit );
+       if ( get_assert( op ) &&
+               ( test_filter( op, e, get_assertion( op )) != LDAP_COMPARE_TRUE ))
+       {
+               rs->sr_err = LDAP_ASSERTION_FAILED;
+#ifdef SLAP_ZONE_ALLOC
+               slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+               if ( e != &e_root ) {
+                       bdb_cache_return_entry_r(bdb->bi_dbenv, &bdb->bi_cache, e, &lock);
+               }
+               send_ldap_result( op, rs );
+               return 1;
        }
 
-       /* The time/size limits come first because they require very little
-        * effort, so there's no chance the candidates are selected and then 
-        * the request is not honored only because of time/size constraints */
+       /* compute it anyway; root does not use it */
+       stoptime = op->o_time + op->ors_tlimit;
 
-       /* if no time limit requested, use soft limit (unless root!) */
-       if ( isroot ) {
-               if ( tlimit == 0 ) {
-                       tlimit = -1;    /* allow root to set no limit */
-               }
+       /* need normalized dn below */
+       ber_dupbv( &realbase, &e->e_nname );
 
-               if ( slimit == 0 ) {
-                       slimit = -1;
-               }
+       /* Copy info to base, must free entry before accessing the database
+        * in search_candidates, to avoid deadlocks.
+        */
+       base.e_private = e->e_private;
+       base.e_nname = realbase;
+       base.e_id = e->e_id;
 
-       } else {
-               /* if no limit is required, use soft limit */
-               if ( tlimit <= 0 ) {
-                       tlimit = limit->lms_t_soft;
-
-               /* if requested limit higher than hard limit, abort */
-               } else if ( tlimit > limit->lms_t_hard ) {
-                       /* no hard limit means use soft instead */
-                       if ( limit->lms_t_hard == 0 ) {
-                               tlimit = limit->lms_t_soft;
-
-                       /* positive hard limit means abort */
-                       } else if ( limit->lms_t_hard > 0 ) {
-                               send_search_result( conn, op, 
-                                               LDAP_UNWILLING_TO_PERFORM,
-                                               NULL, NULL, NULL, NULL, 0 );
-                               rc = 0;
-                               goto done;
-                       }
-               
-                       /* negative hard limit means no limit */
-               }
-               
-               /* if no limit is required, use soft limit */
-               if ( slimit <= 0 ) {
-                       slimit = limit->lms_s_soft;
-
-               /* if requested limit higher than hard limit, abort */
-               } else if ( slimit > limit->lms_s_hard ) {
-                       /* no hard limit means use soft instead */
-                       if ( limit->lms_s_hard == 0 ) {
-                               slimit = limit->lms_s_soft;
-
-                       /* positive hard limit means abort */
-                       } else if ( limit->lms_s_hard > 0 ) {
-                               send_search_result( conn, op, 
-                                               LDAP_UNWILLING_TO_PERFORM,
-                                               NULL, NULL, NULL, NULL, 0 );
-                               rc = 0; 
-                               goto done;
-                       }
-                       
-                       /* negative hard limit means no limit */
-               }
+#ifdef SLAP_ZONE_ALLOC
+       slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+       if ( e != &e_root ) {
+               bdb_cache_return_entry_r(bdb->bi_dbenv, &bdb->bi_cache, e, &lock);
        }
-
-       /* compute it anyway; root does not use it */
-       stoptime = op->o_time + tlimit;
+       e = NULL;
 
        /* select candidates */
-       if ( scope == LDAP_SCOPE_BASE ) {
-               rc = base_candidate( be, e, candidates );
+       if ( op->oq_search.rs_scope == LDAP_SCOPE_BASE ) {
+               rs->sr_err = base_candidate( op->o_bd, &base, candidates );
 
        } else {
-               BDB_IDL_ALL( bdb, candidates );
-               rc = search_candidates( be, op, e, filter,
-                       scope, deref, candidates );
+               BDB_IDL_ZERO( candidates );
+               BDB_IDL_ZERO( scopes );
+               rs->sr_err = search_candidates( op, rs, &base,
+                       locker, candidates, scopes );
        }
 
-       /* need normalized dn below */
-       ber_dupbv( &realbase, &e->e_nname );
-
-       /* start cursor at base entry's id 
-        * FIXME: hack to make "" base work */
-       cursor = e->e_id == NOID ? 1 : e->e_id;
-
-       if ( e != &slap_entry_root ) {
-               bdb_entry_return( be, e );
-       }
-       e = NULL;
+       /* start cursor at beginning of candidates.
+        */
+       cursor = 0;
 
        if ( candidates[0] == 0 ) {
-               Debug( LDAP_DEBUG_TRACE, "bdb_search: no candidates\n",
+               Debug( LDAP_DEBUG_TRACE,
+                       LDAP_XSTRING(bdb_search) ": no candidates\n",
                        0, 0, 0 );
 
-               send_search_result( conn, op,
-                       LDAP_SUCCESS,
-                       NULL, NULL, NULL, NULL, 0 );
+               goto nochange;
+       }
 
-               rc = 1;
+       /* if not root and candidates exceed to-be-checked entries, abort */
+       if ( op->ors_limit      /* isroot == FALSE */ &&
+               op->ors_limit->lms_s_unchecked != -1 &&
+               BDB_IDL_N(candidates) > (unsigned) op->ors_limit->lms_s_unchecked )
+       {
+               rs->sr_err = LDAP_ADMINLIMIT_EXCEEDED;
+               send_ldap_result( op, rs );
+               rs->sr_err = LDAP_SUCCESS;
                goto done;
        }
 
-       /* if not root and candidates exceed to-be-checked entries, abort */
-       if ( !isroot && limit->lms_s_unchecked != -1 ) {
-               if ( BDB_IDL_N(candidates) > (unsigned) limit->lms_s_unchecked ) {
-                       send_search_result( conn, op, 
-                                       LDAP_UNWILLING_TO_PERFORM,
-                                       NULL, NULL, NULL, NULL, 0 );
-                       rc = 1;
+       if ( op->ors_limit == NULL      /* isroot == TRUE */ ||
+               !op->ors_limit->lms_s_pr_hide )
+       {
+               tentries = BDB_IDL_N(candidates);
+       }
+
+       if ( get_pagedresults( op ) > SLAP_CONTROL_IGNORED ) {
+               PagedResultsState *ps = op->o_pagedresults_state;
+               /* deferred cookie parsing */
+               rs->sr_err = parse_paged_cookie( op, rs );
+               if ( rs->sr_err != LDAP_SUCCESS ) {
+                       send_ldap_result( op, rs );
                        goto done;
                }
+
+               if ( (ID)( ps->ps_cookie ) == 0 ) {
+                       id = bdb_idl_first( candidates, &cursor );
+
+               } else {
+                       if ( ps->ps_size == 0 ) {
+                               rs->sr_err = LDAP_SUCCESS;
+                               rs->sr_text = "search abandoned by pagedResult size=0";
+                               send_ldap_result( op, rs );
+                               goto done;
+                       }
+                       for ( id = bdb_idl_first( candidates, &cursor );
+                               id != NOID &&
+                                       id <= (ID)( ps->ps_cookie );
+                               id = bdb_idl_next( candidates, &cursor ) )
+                       {
+                               /* empty */;
+                       }
+               }
+
+               if ( cursor == NOID ) {
+                       Debug( LDAP_DEBUG_TRACE, 
+                               LDAP_XSTRING(bdb_search)
+                               ": no paged results candidates\n",
+                               0, 0, 0 );
+                       send_paged_response( op, rs, &lastid, 0 );
+
+                       rs->sr_err = LDAP_OTHER;
+                       goto done;
+               }
+               goto loop_begin;
        }
 
        for ( id = bdb_idl_first( candidates, &cursor );
-               id != NOID;
-               id = bdb_idl_next( candidates, &cursor ) )
+                 id != NOID ; id = bdb_idl_next( candidates, &cursor ) )
        {
-               int             scopeok = 0;
+               int scopeok;
 
-               /* check for abandon */
-               ldap_pvt_thread_mutex_lock( &op->o_abandonmutex );
-               abandon = op->o_abandon;
-               ldap_pvt_thread_mutex_unlock( &op->o_abandonmutex );
+loop_begin:
 
-               if ( abandon ) {
-                       rc = 0;
+               /* check for abandon */
+               if ( op->o_abandon ) {
+                       rs->sr_err = SLAPD_ABANDON;
                        goto done;
                }
 
                /* check time limit */
-               if ( tlimit != -1 && slap_get_time() > stoptime ) {
-                       send_search_result( conn, op, rc = LDAP_TIMELIMIT_EXCEEDED,
-                               NULL, NULL, v2refs, NULL, nentries );
+               if ( op->ors_tlimit != SLAP_NO_LIMIT
+                               && slap_get_time() > stoptime )
+               {
+                       rs->sr_err = LDAP_TIMELIMIT_EXCEEDED;
+                       rs->sr_ref = rs->sr_v2ref;
+                       send_ldap_result( op, rs );
+                       rs->sr_err = LDAP_SUCCESS;
                        goto done;
                }
 
-               /* get the entry with reader lock */
-               rc = bdb_id2entry( be, NULL, id, &e );
+fetch_entry_retry:
+                       /* get the entry with reader lock */
+                       ei = NULL;
+                       rs->sr_err = bdb_cache_find_id( op, ltid,
+                               id, &ei, 0, locker, &lock );
+
+                       if (rs->sr_err == LDAP_BUSY) {
+                               rs->sr_text = "ldap server busy";
+                               send_ldap_result( op, rs );
+                               goto done;
 
-               if ( e == NULL ) {
-                       if( !BDB_IDL_IS_RANGE(candidates) ) {
-                               /* only complain for non-range IDLs */
-                               Debug( LDAP_DEBUG_TRACE,
-                                       "bdb_search: candidate %ld not found\n",
-                                       (long) id, 0, 0 );
+                       } else if ( rs->sr_err == DB_LOCK_DEADLOCK
+                               || rs->sr_err == DB_LOCK_NOTGRANTED )
+                       {
+                               goto fetch_entry_retry;
                        }
 
-                       goto loop_continue;
-               }
+                       if ( ei && rs->sr_err == LDAP_SUCCESS ) {
+                               e = ei->bei_e;
+                       } else {
+                               e = NULL;
+                       }
+
+                       if ( e == NULL ) {
+                               if( !BDB_IDL_IS_RANGE(candidates) ) {
+                                       /* only complain for non-range IDLs */
+                                       Debug( LDAP_DEBUG_TRACE,
+                                               LDAP_XSTRING(bdb_search)
+                                               ": candidate %ld not found\n",
+                                               (long) id, 0, 0 );
+                               }
+
+                               goto loop_continue;
+                       }
+
+               rs->sr_entry = e;
 
                if ( is_entry_subentry( e ) ) {
-                       if( scope != LDAP_SCOPE_BASE ) {
+                       if( op->oq_search.rs_scope != LDAP_SCOPE_BASE ) {
                                if(!get_subentries_visibility( op )) {
                                        /* only subentries are visible */
                                        goto loop_continue;
                                }
+
                        } else if ( get_subentries( op ) &&
                                !get_subentries_visibility( op ))
                        {
                                /* only subentries are visible */
                                goto loop_continue;
                        }
+
                } else if ( get_subentries_visibility( op )) {
                        /* only subentries are visible */
                        goto loop_continue;
                }
 
-#ifdef BDB_ALIASES
-               if ( deref & LDAP_DEREF_SEARCHING && is_entry_alias( e ) ) {
-                       Entry *matched;
-                       int err;
-                       const char *text;
-                       
-                       e = deref_entry_r( be, e, &err, &matched, &text );
-
-                       if( e == NULL ) {
-                               e = matched;
-                               goto loop_continue;
+               /* Does this candidate actually satisfy the search scope?
+                *
+                * Note that we don't lock access to the bei_parent pointer.
+                * Since only leaf nodes can be deleted, the parent of any
+                * node will always be a valid node. Also since we have
+                * a Read lock on the data, it cannot be renamed out of the
+                * scope while we are looking at it, and unless we're using
+                * BDB_HIER, its parents cannot be moved either.
+                */
+               scopeok = 0;
+               switch( op->ors_scope ) {
+               case LDAP_SCOPE_BASE:
+                       /* This is always true, yes? */
+                       if ( id == base.e_id ) scopeok = 1;
+                       break;
+
+               case LDAP_SCOPE_ONELEVEL:
+                       if ( ei->bei_parent->bei_id == base.e_id ) scopeok = 1;
+                       break;
+
+#ifdef LDAP_SCOPE_CHILDREN
+               case LDAP_SCOPE_CHILDREN:
+                       if ( id == base.e_id ) break;
+                       /* Fall-thru */
+#endif
+               case LDAP_SCOPE_SUBTREE: {
+                       EntryInfo *tmp;
+                       for ( tmp = BEI(e); tmp; tmp = tmp->bei_parent ) {
+                               if ( tmp->bei_id == base.e_id ) {
+                                       scopeok = 1;
+                                       break;
+                               }
                        }
+                       } break;
+               }
 
-                       if( e->e_id == id ) {
-                               /* circular loop */
+               /* aliases were already dereferenced in candidate list */
+               if ( op->ors_deref & LDAP_DEREF_SEARCHING ) {
+                       /* but if the search base is an alias, and we didn't
+                        * deref it when finding, return it.
+                        */
+                       if ( is_entry_alias(e) &&
+                               ((op->ors_deref & LDAP_DEREF_FINDING) ||
+                                       !bvmatch(&e->e_nname, &op->o_req_ndn)))
+                       {
                                goto loop_continue;
                        }
 
-                       /* need to skip alias which deref into scope */
-                       if( scope & LDAP_SCOPE_ONELEVEL ) {
-                               char *pdn = dn_parent( NULL, e->e_ndn );
-                               if ( pdn != NULL ) {
-                                       if( strcmp( pdn, realbase.bv_val ) ) {
-                                               goto loop_continue;
+                       /* scopes is only non-empty for onelevel or subtree */
+                       if ( !scopeok && BDB_IDL_N(scopes) ) {
+                               unsigned x;
+                               if ( op->ors_scope == LDAP_SCOPE_ONELEVEL ) {
+                                       x = bdb_idl_search( scopes, e->e_id );
+                                       if ( scopes[x] == e->e_id ) scopeok = 1;
+                               } else {
+                                       /* subtree, walk up the tree */
+                                       EntryInfo *tmp = BEI(e);
+                                       for (;tmp->bei_parent; tmp=tmp->bei_parent) {
+                                               x = bdb_idl_search( scopes, tmp->bei_id );
+                                               if ( scopes[x] == tmp->bei_id ) {
+                                                       scopeok = 1;
+                                                       break;
+                                               }
                                        }
                                }
-
-                       } else if ( dnIsSuffix( &e->e_nname, &realbase ) ) {
-                               /* alias is within scope */
-                               Debug( LDAP_DEBUG_TRACE,
-                                       "bdb_search: \"%s\" in subtree\n",
-                                       e->e_dn, 0, 0 );
-                               goto loop_continue;
                        }
+               }
 
-                       scopeok = 1;
+               /* Not in scope, ignore it */
+               if ( !scopeok )
+               {
+                       Debug( LDAP_DEBUG_TRACE,
+                               LDAP_XSTRING(bdb_search)
+                               ": %ld scope not okay\n",
+                               (long) id, 0, 0 );
+                       goto loop_continue;
                }
-#endif
 
                /*
                 * if it's a referral, add it to the list of referrals. only do
                 * this for non-base searches, and don't check the filter
                 * explicitly here since it's only a candidate anyway.
                 */
-               if ( !manageDSAit && scope != LDAP_SCOPE_BASE &&
-                       is_entry_referral( e ) )
+               if ( !manageDSAit && op->oq_search.rs_scope != LDAP_SCOPE_BASE
+                       && is_entry_referral( e ) )
                {
-                       BerVarray erefs = get_entry_referrals(
-                               be, conn, op, e );
-                       BerVarray refs = referral_rewrite( erefs,
-                               &e->e_name, NULL,
-                               scope == LDAP_SCOPE_SUBTREE 
-                                       ? LDAP_SCOPE_SUBTREE
-                                       : LDAP_SCOPE_BASE );
+                       BerVarray erefs = get_entry_referrals( op, e );
+                       rs->sr_ref = referral_rewrite( erefs, &e->e_name, NULL,
+                               op->oq_search.rs_scope == LDAP_SCOPE_ONELEVEL
+                                       ? LDAP_SCOPE_BASE : LDAP_SCOPE_SUBTREE );
 
-                       send_search_reference( be, conn, op,
-                               e, refs, NULL, &v2refs );
+                       send_search_reference( op, rs );
 
-                       ber_bvarray_free( refs );
+                       ber_bvarray_free( rs->sr_ref );
+                       ber_bvarray_free( erefs );
+                       rs->sr_ref = NULL;
 
                        goto loop_continue;
                }
 
-               /* if it matches the filter and scope, send it */
-               rc = test_filter( be, conn, op, e, filter );
-               if ( rc == LDAP_COMPARE_TRUE ) {
-                       char    *dn;
-
-                       /* check scope */
-                       if ( !scopeok && scope == LDAP_SCOPE_ONELEVEL ) {
-                               if ( (dn = dn_parent( be, e->e_ndn )) != NULL ) {
-                                       scopeok = (dn == realbase.bv_val)
-                                               ? 1
-                                               : (strcmp( dn, realbase.bv_val ) ? 0 : 1 );
-                               } else {
-                                       scopeok = (realbase.bv_len == 0);
-                               }
-
-                       } else if ( !scopeok && scope == LDAP_SCOPE_SUBTREE ) {
-                               scopeok = dnIsSuffix( &e->e_nname, &realbase );
-
-                       } else {
-                               scopeok = 1;
-                       }
+               if ( !manageDSAit && is_entry_glue( e )) {
+                       goto loop_continue;
+               }
 
-                       if ( scopeok ) {
-                               /* check size limit */
-                               if ( --slimit == -1 ) {
-                                       bdb_entry_return( be, e );
+               /* if it matches the filter and scope, send it */
+               rs->sr_err = test_filter( op, rs->sr_entry, op->oq_search.rs_filter );
+
+               if ( rs->sr_err == LDAP_COMPARE_TRUE ) {
+                       /* check size limit */
+                       if ( get_pagedresults(op) > SLAP_CONTROL_IGNORED ) {
+                               if ( rs->sr_nentries >= ((PagedResultsState *)op->o_pagedresults_state)->ps_size ) {
+#ifdef SLAP_ZONE_ALLOC
+                                       slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+                                       bdb_cache_return_entry_r( bdb->bi_dbenv,
+                                                       &bdb->bi_cache, e, &lock );
                                        e = NULL;
-                                       send_search_result( conn, op,
-                                               rc = LDAP_SIZELIMIT_EXCEEDED, NULL, NULL,
-                                               v2refs, NULL, nentries );
+                                       send_paged_response( op, rs, &lastid, tentries );
                                        goto done;
                                }
+                               lastid = id;
+                       }
 
-                               if (e) {
-                                       int result = send_search_entry( be, conn, op,
-                                               e, attrs, attrsonly, NULL);
-
-                                       switch (result) {
-                                       case 0:         /* entry sent ok */
-                                               nentries++;
-                                               break;
-                                       case 1:         /* entry not sent */
-                                               break;
-                                       case -1:        /* connection closed */
-                                               bdb_entry_return( be, e );
-                                               e = NULL;
-                                               rc = LDAP_OTHER;
-                                               goto done;
+                       if (e) {
+                               /* safe default */
+                               rs->sr_attrs = op->oq_search.rs_attrs;
+                               rs->sr_operational_attrs = NULL;
+                               rs->sr_ctrls = NULL;
+                               rs->sr_flags = 0;
+                               rs->sr_err = LDAP_SUCCESS;
+                               rs->sr_err = send_search_entry( op, rs );
+
+                               switch ( rs->sr_err ) {
+                               case LDAP_SUCCESS:      /* entry sent ok */
+                                       break;
+                               default:                /* entry not sent */
+                                       break;
+                               case LDAP_UNAVAILABLE:
+                               case LDAP_SIZELIMIT_EXCEEDED:
+#ifdef SLAP_ZONE_ALLOC
+                                       slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+                                       bdb_cache_return_entry_r(bdb->bi_dbenv,
+                                               &bdb->bi_cache, e, &lock);
+                                       e = NULL;
+                                       rs->sr_entry = NULL;
+                                       if ( rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ) {
+                                               rs->sr_ref = rs->sr_v2ref;
+                                               send_ldap_result( op, rs );
+                                               rs->sr_err = LDAP_SUCCESS;
+
+                                       } else {
+                                               rs->sr_err = LDAP_OTHER;
                                        }
+                                       goto done;
                                }
-                       } else {
-                               Debug( LDAP_DEBUG_TRACE,
-                                       "bdb_search: %ld scope not okay\n",
-                                       (long) id, 0, 0 );
                        }
+
                } else {
                        Debug( LDAP_DEBUG_TRACE,
-                               "bdb_search: %ld does match filter\n",
+                               LDAP_XSTRING(bdb_search)
+                               ": %ld does not match filter\n",
                                (long) id, 0, 0 );
                }
 
 loop_continue:
                if( e != NULL ) {
                        /* free reader lock */
-                       bdb_entry_return( be, e );
+#ifdef SLAP_ZONE_ALLOC
+                       slap_zn_runlock(bdb->bi_cache.c_zctx, e);
+#endif
+                       bdb_cache_return_entry_r( bdb->bi_dbenv,
+                               &bdb->bi_cache, e , &lock );
+                       e = NULL;
+                       rs->sr_entry = NULL;
                }
+       }
 
-               ldap_pvt_thread_yield();
+nochange:
+       rs->sr_ctrls = NULL;
+       rs->sr_ref = rs->sr_v2ref;
+       rs->sr_err = (rs->sr_v2ref == NULL) ? LDAP_SUCCESS : LDAP_REFERRAL;
+       rs->sr_rspoid = NULL;
+       if ( get_pagedresults(op) > SLAP_CONTROL_IGNORED ) {
+               send_paged_response( op, rs, NULL, 0 );
+       } else {
+               send_ldap_result( op, rs );
        }
-       send_search_result( conn, op,
-               v2refs == NULL ? LDAP_SUCCESS : LDAP_REFERRAL,
-               NULL, NULL, v2refs, NULL, nentries );
 
-       rc = 0;
+       rs->sr_err = LDAP_SUCCESS;
 
 done:
-       if( v2refs ) ber_bvarray_free( v2refs );
+       if ( !opinfo )
+               LOCK_ID_FREE( bdb->bi_dbenv, locker );
+
+       if( rs->sr_v2ref ) {
+               ber_bvarray_free( rs->sr_v2ref );
+               rs->sr_v2ref = NULL;
+       }
        if( realbase.bv_val ) ch_free( realbase.bv_val );
 
-       return rc;
+       return rs->sr_err;
 }
 
 
@@ -478,64 +957,100 @@ static int base_candidate(
        ID              *ids )
 {
        Debug(LDAP_DEBUG_ARGS, "base_candidates: base: \"%s\" (0x%08lx)\n",
-               e->e_dn, (long) e->e_id, 0);
+               e->e_nname.bv_val, (long) e->e_id, 0);
 
        ids[0] = 1;
        ids[1] = e->e_id;
        return 0;
 }
 
-/* Is "objectClass=xx" mentioned anywhere in this filter? Presence
- * doesn't count, we're looking for explicit values.
+/* Look for "objectClass Present" in this filter.
+ * Also count depth of filter tree while we're at it.
  */
 static int oc_filter(
-       Filter *f
-)
+       Filter *f,
+       int cur,
+       int *max )
 {
        int rc = 0;
 
-       switch(f->f_choice) {
-       case LDAP_FILTER_EQUALITY:
-       case LDAP_FILTER_APPROX:
-               if (f->f_av_desc == slap_schema.si_ad_objectClass)
-                       rc = 1;
-               break;
+       assert( f != NULL );
 
-       case LDAP_FILTER_SUBSTRINGS:
-               if (f->f_sub_desc == slap_schema.si_ad_objectClass)
+       if( cur > *max ) *max = cur;
+
+       switch( f->f_choice ) {
+       case LDAP_FILTER_PRESENT:
+               if (f->f_desc == slap_schema.si_ad_objectClass) {
                        rc = 1;
+               }
                break;
 
        case LDAP_FILTER_AND:
        case LDAP_FILTER_OR:
-               for (f=f->f_and; f; f=f->f_next)
-                       if ((rc = oc_filter(f)))
-                               break;
+               cur++;
+               for ( f=f->f_and; f; f=f->f_next ) {
+                       (void) oc_filter(f, cur, max);
+               }
                break;
+
        default:
                break;
        }
        return rc;
 }
 
+static void search_stack_free( void *key, void *data )
+{
+       ber_memfree_x(data, NULL);
+}
+
+static void *search_stack( Operation *op )
+{
+       struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
+       void *ret = NULL;
+
+       if ( op->o_threadctx ) {
+               ldap_pvt_thread_pool_getkey( op->o_threadctx, search_stack,
+                       &ret, NULL );
+       } else {
+               ret = bdb->bi_search_stack;
+       }
+
+       if ( !ret ) {
+               ret = ch_malloc( bdb->bi_search_stack_depth * BDB_IDL_UM_SIZE
+                       * sizeof( ID ) );
+               if ( op->o_threadctx ) {
+                       ldap_pvt_thread_pool_setkey( op->o_threadctx, search_stack,
+                               ret, search_stack_free );
+               } else {
+                       bdb->bi_search_stack = ret;
+               }
+       }
+       return ret;
+}
+
 static int search_candidates(
-       BackendDB *be,
        Operation *op,
+       SlapReply *rs,
        Entry *e,
-       Filter *filter,
-       int scope,
-       int deref,
-       ID      *ids )
+       u_int32_t locker,
+       ID      *ids,
+       ID      *scopes )
 {
-       int rc;
-       Filter          f, scopef, sf, rf, xf;
-       ID              tmp[BDB_IDL_UM_SIZE];
-       AttributeAssertion aa_ref;
-       AttributeAssertion aa_subentry;
-       struct bdb_info *bdb = (struct bdb_info *) be->be_private;
-#ifdef BDB_ALIASES
-       Filter  af;
-       AttributeAssertion aa_alias;
+       struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
+       int rc, depth = 1;
+       Filter          f, rf, xf, nf;
+       ID              *stack;
+#ifdef LDAP_COMP_MATCH
+       AttributeAssertion aa_ref = { NULL, BER_BVNULL, NULL };
+#else
+       AttributeAssertion aa_ref = { NULL, BER_BVNULL };
+#endif
+       Filter  sf;
+#ifdef LDAP_COMP_MATCH
+       AttributeAssertion aa_subentry = { NULL, BER_BVNULL, NULL };
+#else
+       AttributeAssertion aa_subentry = { NULL, BER_BVNULL };
 #endif
 
        /*
@@ -547,74 +1062,241 @@ static int search_candidates(
 
        Debug(LDAP_DEBUG_TRACE,
                "search_candidates: base=\"%s\" (0x%08lx) scope=%d\n",
-               e->e_dn, (long) e->e_id, scope );
+               e->e_nname.bv_val, (long) e->e_id, op->oq_search.rs_scope );
 
-       xf.f_or = filter;
+       xf.f_or = op->oq_search.rs_filter;
        xf.f_choice = LDAP_FILTER_OR;
        xf.f_next = NULL;
 
-       /* If the user's filter doesn't mention objectClass, or if
-        * it just uses objectClass=*, these clauses are redundant.
+       /* If the user's filter uses objectClass=*,
+        * these clauses are redundant.
         */
-       if (oc_filter(filter) && !get_subentries_visibility(op) ) {
-               if( !get_manageDSAit(op) ) { /* match referrals */
-                       struct berval bv_ref = { sizeof("REFERRAL")-1, "REFERRAL" };
+       if (!oc_filter(op->oq_search.rs_filter, 1, &depth)
+               && !get_subentries_visibility(op)) {
+               if( !get_manageDSAit(op) && !get_domainScope(op) ) {
+                       /* match referral objects */
+                       struct berval bv_ref = BER_BVC( "referral" );
                        rf.f_choice = LDAP_FILTER_EQUALITY;
                        rf.f_ava = &aa_ref;
                        rf.f_av_desc = slap_schema.si_ad_objectClass;
                        rf.f_av_value = bv_ref;
                        rf.f_next = xf.f_or;
                        xf.f_or = &rf;
+                       depth++;
                }
-
-#ifdef BDB_ALIASES
-               if( deref & LDAP_DEREF_SEARCHING ) { /* match aliases */
-                       struct berval bv_alias = { sizeof("ALIAS")-1, "ALIAS" };
-                       af.f_choice = LDAP_FILTER_EQUALITY;
-                       af.f_ava = &aa_alias;
-                       af.f_av_desc = slap_schema.si_ad_objectClass;
-                       af.f_av_value = bv_alias;
-                       af.f_next = xf.f_or;
-                       xf.f_or = &af;
-               }
-#endif
        }
 
        f.f_next = NULL;
        f.f_choice = LDAP_FILTER_AND;
-       f.f_and = &scopef;
-       scopef.f_choice = scope == LDAP_SCOPE_SUBTREE
-               ? SLAPD_FILTER_DN_SUBTREE
-               : SLAPD_FILTER_DN_ONE;
-       scopef.f_dn = &e->e_nname;
-       scopef.f_next = xf.f_or == filter ? filter : &xf ;
+       f.f_and = &nf;
+       /* Dummy; we compute scope separately now */
+       nf.f_choice = SLAPD_FILTER_COMPUTED;
+       nf.f_result = LDAP_SUCCESS;
+       nf.f_next = ( xf.f_or == op->oq_search.rs_filter )
+               ? op->oq_search.rs_filter : &xf ;
+       /* Filter depth increased again, adding dummy clause */
+       depth++;
 
        if( get_subentries_visibility( op ) ) {
-               struct berval bv_subentry = { sizeof("SUBENTRY")-1, "SUBENTRY" };
+               struct berval bv_subentry = BER_BVC( "subentry" );
                sf.f_choice = LDAP_FILTER_EQUALITY;
                sf.f_ava = &aa_subentry;
                sf.f_av_desc = slap_schema.si_ad_objectClass;
                sf.f_av_value = bv_subentry;
-               sf.f_next = scopef.f_next;
-               scopef.f_next = &sf;
+               sf.f_next = nf.f_next;
+               nf.f_next = &sf;
        }
 
-#ifdef BDB_FILTER_INDICES
-       rc = bdb_filter_candidates( be, &f, ids, tmp );
-#else
-       /* FIXME: Original code:
-       BDB_IDL_ID( bdb, ids, e->e_id );
-       * this is a hack to make "" base work; when bdb_filter_candidates
-       * is used this should not be needed any more */
-       BDB_IDL_ID( bdb, ids, (e->e_id == NOID ? 1 : e->e_id) );
-       rc = 0;
+       /* Allocate IDL stack, plus 1 more for former tmp */
+       if ( depth+1 > bdb->bi_search_stack_depth ) {
+               stack = ch_malloc( (depth + 1) * BDB_IDL_UM_SIZE * sizeof( ID ) );
+       } else {
+               stack = search_stack( op );
+       }
+
+       if( op->ors_deref & LDAP_DEREF_SEARCHING ) {
+               rc = search_aliases( op, rs, e, locker, ids, scopes, stack );
+       } else {
+               rc = bdb_dn2idl( op, e, ids, stack );
+       }
+
+       if ( rc == LDAP_SUCCESS ) {
+               rc = bdb_filter_candidates( op, &f, ids,
+                       stack, stack+BDB_IDL_UM_SIZE );
+       }
+
+       if ( depth+1 > bdb->bi_search_stack_depth ) {
+               ch_free( stack );
+       }
+
+       if( rc ) {
+               Debug(LDAP_DEBUG_TRACE,
+                       "bdb_search_candidates: failed (rc=%d)\n",
+                       rc, NULL, NULL );
+
+       } else {
+               Debug(LDAP_DEBUG_TRACE,
+                       "bdb_search_candidates: id=%ld first=%ld last=%ld\n",
+                       (long) ids[0],
+                       (long) BDB_IDL_FIRST(ids),
+                       (long) BDB_IDL_LAST(ids) );
+       }
+
+       return rc;
+}
+
+static int
+parse_paged_cookie( Operation *op, SlapReply *rs )
+{
+       LDAPControl     **c;
+       int             rc = LDAP_SUCCESS;
+       ber_tag_t       tag;
+       ber_int_t       size;
+       BerElement      *ber;
+       struct berval   cookie = BER_BVNULL;
+       PagedResultsState *ps = op->o_pagedresults_state;
+
+       /* this function must be invoked only if the pagedResults
+        * control has been detected, parsed and partially checked
+        * by the frontend */
+       assert( get_pagedresults( op ) > SLAP_CONTROL_IGNORED );
+
+       /* look for the appropriate ctrl structure */
+       for ( c = op->o_ctrls; c[0] != NULL; c++ ) {
+               if ( strcmp( c[0]->ldctl_oid, LDAP_CONTROL_PAGEDRESULTS ) == 0 )
+               {
+                       break;
+               }
+       }
+
+       if ( c[0] == NULL ) {
+               rs->sr_text = "missing pagedResults control";
+               return LDAP_PROTOCOL_ERROR;
+       }
+
+       /* Tested by frontend */
+       assert( c[0]->ldctl_value.bv_len > 0 );
+
+       /* Parse the control value
+        *      realSearchControlValue ::= SEQUENCE {
+        *              size    INTEGER (0..maxInt),
+        *                              -- requested page size from client
+        *                              -- result set size estimate from server
+        *              cookie  OCTET STRING
+        * }
+        */
+       ber = ber_init( &c[0]->ldctl_value );
+       if ( ber == NULL ) {
+               rs->sr_text = "internal error";
+               return LDAP_OTHER;
+       }
+
+       tag = ber_scanf( ber, "{im}", &size, &cookie );
+
+       /* Tested by frontend */
+       assert( tag != LBER_ERROR );
+       assert( size >= 0 );
+
+       /* cookie decoding/checks deferred to backend... */
+       if ( cookie.bv_len ) {
+               PagedResultsCookie reqcookie;
+               if( cookie.bv_len != sizeof( reqcookie ) ) {
+                       /* bad cookie */
+                       rs->sr_text = "paged results cookie is invalid";
+                       rc = LDAP_PROTOCOL_ERROR;
+                       goto done;
+               }
+
+               AC_MEMCPY( &reqcookie, cookie.bv_val, sizeof( reqcookie ));
+
+               if ( reqcookie > ps->ps_cookie ) {
+                       /* bad cookie */
+                       rs->sr_text = "paged results cookie is invalid";
+                       rc = LDAP_PROTOCOL_ERROR;
+                       goto done;
+
+               } else if ( reqcookie < ps->ps_cookie ) {
+                       rs->sr_text = "paged results cookie is invalid or old";
+                       rc = LDAP_UNWILLING_TO_PERFORM;
+                       goto done;
+               }
+
+       } else {
+               /* Initial request.  Initialize state. */
+#if 0
+               if ( op->o_conn->c_pagedresults_state.ps_cookie != 0 ) {
+                       /* There's another pagedResults control on the
+                        * same connection; reject new pagedResults controls 
+                        * (allowed by RFC2696) */
+                       rs->sr_text = "paged results cookie unavailable; try later";
+                       rc = LDAP_UNWILLING_TO_PERFORM;
+                       goto done;
+               }
 #endif
+               ps->ps_cookie = 0;
+               ps->ps_count = 0;
+       }
 
-       Debug(LDAP_DEBUG_TRACE,
-               "bdb_search_candidates: id=%ld first=%ld last=%ld\n",
-               (long) ids[0],
-               (long) BDB_IDL_FIRST(ids),
-               (long) BDB_IDL_LAST(ids) );
+done:;
+       (void)ber_free( ber, 1 );
 
        return rc;
 }
+
+static void
+send_paged_response( 
+       Operation       *op,
+       SlapReply       *rs,
+       ID              *lastid,
+       int             tentries )
+{
+       LDAPControl     ctrl, *ctrls[2];
+       BerElementBuffer berbuf;
+       BerElement      *ber = (BerElement *)&berbuf;
+       PagedResultsCookie respcookie;
+       struct berval cookie;
+
+       Debug(LDAP_DEBUG_ARGS,
+               "send_paged_response: lastid=0x%08lx nentries=%d\n", 
+               lastid ? *lastid : 0, rs->sr_nentries, NULL );
+
+       BER_BVZERO( &ctrl.ldctl_value );
+       ctrls[0] = &ctrl;
+       ctrls[1] = NULL;
+
+       ber_init2( ber, NULL, LBER_USE_DER );
+
+       if ( lastid ) {
+               respcookie = ( PagedResultsCookie )(*lastid);
+               cookie.bv_len = sizeof( respcookie );
+               cookie.bv_val = (char *)&respcookie;
+
+       } else {
+               respcookie = ( PagedResultsCookie )0;
+               BER_BVSTR( &cookie, "" );
+       }
+
+       op->o_conn->c_pagedresults_state.ps_cookie = respcookie;
+       op->o_conn->c_pagedresults_state.ps_count =
+               ((PagedResultsState *)op->o_pagedresults_state)->ps_count +
+               rs->sr_nentries;
+
+       /* return size of 0 -- no estimate */
+       ber_printf( ber, "{iO}", 0, &cookie ); 
+
+       if ( ber_flatten2( ber, &ctrls[0]->ldctl_value, 0 ) == -1 ) {
+               goto done;
+       }
+
+       ctrls[0]->ldctl_oid = LDAP_CONTROL_PAGEDRESULTS;
+       ctrls[0]->ldctl_iscritical = 0;
+
+       rs->sr_ctrls = ctrls;
+       rs->sr_err = LDAP_SUCCESS;
+       send_ldap_result( op, rs );
+       rs->sr_ctrls = NULL;
+
+done:
+       (void) ber_free_buf( ber );
+}
+