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[openldap] / servers / slapd / back-ldap / search.c
1 /* search.c - ldap backend search function */
2 /* $OpenLDAP$ */
3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
4  *
5  * Copyright 1999-2005 The OpenLDAP Foundation.
6  * Portions Copyright 1999-2003 Howard Chu.
7  * Portions Copyright 2000-2003 Pierangelo Masarati.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted only as authorized by the OpenLDAP
12  * Public License.
13  *
14  * A copy of this license is available in the file LICENSE in the
15  * top-level directory of the distribution or, alternatively, at
16  * <http://www.OpenLDAP.org/license.html>.
17  */
18 /* ACKNOWLEDGEMENTS:
19  * This work was initially developed by the Howard Chu for inclusion
20  * in OpenLDAP Software and subsequently enhanced by Pierangelo
21  * Masarati.
22  */
23
24 #include "portable.h"
25
26 #include <stdio.h>
27
28 #include <ac/socket.h>
29 #include <ac/string.h>
30 #include <ac/time.h>
31
32 #include "slap.h"
33 #include "back-ldap.h"
34 #undef ldap_debug       /* silence a warning in ldap-int.h */
35 #include "../../../libraries/libldap/ldap-int.h"
36
37 #include "lutil.h"
38
39 static int
40 ldap_build_entry( Operation *op, LDAPMessage *e, Entry *ent,
41          struct berval *bdn );
42
43 /*
44  * Quick'n'dirty rewrite of filter in case of error, to deal with
45  * <draft-zeilenga-ldap-t-f>.
46  */
47 static int
48 ldap_back_munge_filter(
49         Operation       *op,
50         struct berval   *filter )
51 {
52         struct ldapinfo *li = (struct ldapinfo *) op->o_bd->be_private;
53
54         char            *ptr;
55         int             gotit = 0;
56
57         Debug( LDAP_DEBUG_ARGS, "=> ldap_back_munge_filter \"%s\"\n",
58                         filter->bv_val, 0, 0 );
59
60         for ( ptr = strstr( filter->bv_val, "(?=" ); 
61                         ptr;
62                         ptr = strstr( ptr, "(?=" ) )
63         {
64                 static struct berval
65                         bv_true = BER_BVC( "(?=true)" ),
66                         bv_false = BER_BVC( "(?=false)" ),
67                         bv_undefined = BER_BVC( "(?=undefined)" ),
68                         bv_t = BER_BVC( "(&)" ),
69                         bv_f = BER_BVC( "(|)" ),
70                         bv_T = BER_BVC( "(objectClass=*)" ),
71                         bv_F = BER_BVC( "(!(objectClass=*))" );
72                 struct berval   *oldbv = NULL,
73                                 *newbv = NULL,
74                                 oldfilter = BER_BVNULL;
75
76                 if ( strncmp( ptr, bv_true.bv_val, bv_true.bv_len ) == 0 ) {
77                         oldbv = &bv_true;
78                         if ( li->flags & LDAP_BACK_F_SUPPORT_T_F ) {
79                                 newbv = &bv_t;
80
81                         } else {
82                                 newbv = &bv_T;
83                         }
84
85                 } else if ( strncmp( ptr, bv_false.bv_val, bv_false.bv_len ) == 0 )
86                 {
87                         oldbv = &bv_false;
88                         if ( li->flags & LDAP_BACK_F_SUPPORT_T_F ) {
89                                 newbv = &bv_f;
90
91                         } else {
92                                 newbv = &bv_F;
93                         }
94
95                 } else if ( strncmp( ptr, bv_undefined.bv_val, bv_undefined.bv_len ) == 0 )
96                 {
97                         oldbv = &bv_undefined;
98                         newbv = &bv_F;
99
100                 } else {
101                         gotit = 0;
102                         goto done;
103                 }
104
105                 oldfilter = *filter;
106                 if ( newbv->bv_len > oldbv->bv_len ) {
107                         filter->bv_len += newbv->bv_len - oldbv->bv_len;
108                         if ( filter->bv_val == op->ors_filterstr.bv_val ) {
109                                 filter->bv_val = op->o_tmpalloc( filter->bv_len + 1,
110                                                 op->o_tmpmemctx );
111
112                                 AC_MEMCPY( filter->bv_val, op->ors_filterstr.bv_val,
113                                                 op->ors_filterstr.bv_len + 1 );
114
115                         } else {
116                                 filter->bv_val = op->o_tmprealloc( filter->bv_val,
117                                                 filter->bv_len + 1, op->o_tmpmemctx );
118                         }
119
120                         ptr = filter->bv_val + ( ptr - oldfilter.bv_val );
121                 }
122
123                 AC_MEMCPY( &ptr[ newbv->bv_len ],
124                                 &ptr[ oldbv->bv_len ], 
125                                 oldfilter.bv_len - ( ptr - filter->bv_val ) - oldbv->bv_len + 1 );
126                 AC_MEMCPY( ptr, newbv->bv_val, newbv->bv_len );
127
128                 ptr += newbv->bv_len;
129                 gotit = 1;
130         }
131
132 done:;
133         Debug( LDAP_DEBUG_ARGS, "<= ldap_back_munge_filter \"%s\" (%d)\n",
134                         filter->bv_val, gotit, 0 );
135
136         return gotit;
137 }
138
139 int
140 ldap_back_search(
141                 Operation       *op,
142                 SlapReply       *rs )
143 {
144         struct ldapconn *lc;
145         struct timeval  tv;
146         time_t          stoptime;
147         LDAPMessage     *res,
148                         *e;
149         int             rc = 0,
150                         msgid; 
151         struct berval   match = BER_BVNULL,
152                         filter = BER_BVNULL;
153         int             i;
154         char            **attrs = NULL;
155         int             freetext = 0;
156         int             do_retry = 1;
157         LDAPControl     **ctrls = NULL;
158
159         lc = ldap_back_getconn( op, rs, LDAP_BACK_SENDERR );
160         if ( !lc || !ldap_back_dobind( lc, op, rs, LDAP_BACK_SENDERR ) ) {
161                 return rs->sr_err;
162         }
163
164         /*
165          * FIXME: in case of values return filter, we might want
166          * to map attrs and maybe rewrite value
167          */
168
169         /* should we check return values? */
170         if ( op->ors_deref != -1 ) {
171                 ldap_set_option( lc->lc_ld, LDAP_OPT_DEREF,
172                                 (void *)&op->ors_deref );
173         }
174
175         if ( op->ors_tlimit != SLAP_NO_LIMIT ) {
176                 tv.tv_sec = op->ors_tlimit;
177                 tv.tv_usec = 0;
178                 stoptime = op->o_time + op->ors_tlimit;
179
180         } else {
181                 tv.tv_sec = 0;
182         }
183
184         if ( op->ors_attrs ) {
185                 for ( i = 0; !BER_BVISNULL( &op->ors_attrs[i].an_name ); i++ )
186                         /* just count attrs */ ;
187
188                 attrs = ch_malloc( ( i + 1 )*sizeof( char * ) );
189                 if ( attrs == NULL ) {
190                         rs->sr_err = LDAP_NO_MEMORY;
191                         rc = -1;
192                         goto finish;
193                 }
194         
195                 for ( i = 0; !BER_BVISNULL( &op->ors_attrs[i].an_name ); i++ ) {
196                         attrs[ i ] = op->ors_attrs[i].an_name.bv_val;
197                 }
198                 attrs[ i ] = NULL;
199         }
200
201         ctrls = op->o_ctrls;
202         rc = ldap_back_proxy_authz_ctrl( lc, op, rs, &ctrls );
203         if ( rc != LDAP_SUCCESS ) {
204                 goto finish;
205         }
206
207         /* deal with <draft-zeilenga-ldap-t-f> filters */
208         filter = op->ors_filterstr;
209 retry:
210         rs->sr_err = ldap_search_ext( lc->lc_ld, op->o_req_ndn.bv_val,
211                         op->ors_scope, filter.bv_val,
212                         attrs, op->ors_attrsonly, ctrls, NULL,
213                         tv.tv_sec ? &tv : NULL,
214                         op->ors_slimit, &msgid );
215
216         if ( rs->sr_err != LDAP_SUCCESS ) {
217 fail:;
218                 switch ( rs->sr_err ) {
219                 case LDAP_SERVER_DOWN:
220                         if ( do_retry ) {
221                                 do_retry = 0;
222                                 if ( ldap_back_retry( lc, op, rs, LDAP_BACK_DONTSEND ) ) {
223                                         goto retry;
224                                 }
225                         }
226                         rc = ldap_back_op_result( lc, op, rs, msgid, LDAP_BACK_DONTSEND );
227                         ldap_back_freeconn( op, lc );
228                         lc = NULL;
229                         goto finish;
230
231                 case LDAP_FILTER_ERROR:
232                         if ( ldap_back_munge_filter( op, &filter ) ) {
233                                 goto retry;
234                         }
235
236                         /* invalid filters return success with no data */
237                         rs->sr_err = LDAP_SUCCESS;
238                         rs->sr_text = NULL;
239                         goto finish;
240                 
241                 default:
242                         rs->sr_err = slap_map_api2result( rs );
243                         rs->sr_text = NULL;
244                         goto finish;
245                 }
246         }
247
248         /* We pull apart the ber result, stuff it into a slapd entry, and
249          * let send_search_entry stuff it back into ber format. Slow & ugly,
250          * but this is necessary for version matching, and for ACL processing.
251          */
252
253         for ( rc = 0; rc != -1; rc = ldap_result( lc->lc_ld, msgid, 0, &tv, &res ) )
254         {
255                 /* check for abandon */
256                 if ( op->o_abandon ) {
257                         if ( rc > 0 ) {
258                                 ldap_msgfree( res );
259                         }
260                         ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
261                         rc = SLAPD_ABANDON;
262                         goto finish;
263                 }
264
265                 if ( rc == 0 ) {
266                         tv.tv_sec = 0;
267                         tv.tv_usec = 100000;
268                         ldap_pvt_thread_yield();
269
270                         /* check time limit */
271                         if ( op->ors_tlimit != SLAP_NO_LIMIT
272                                         && slap_get_time() > stoptime )
273                         {
274                                 ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
275                                 rc = rs->sr_err = LDAP_TIMELIMIT_EXCEEDED;
276                                 goto finish;
277                         }
278
279                 } else if ( rc == LDAP_RES_SEARCH_ENTRY ) {
280                         Entry           ent = { 0 };
281                         struct berval   bdn = BER_BVNULL;
282                         int             abort = 0;
283
284                         do_retry = 0;
285
286                         e = ldap_first_entry( lc->lc_ld, res );
287                         rc = ldap_build_entry( op, e, &ent, &bdn );
288                         if ( rc == LDAP_SUCCESS ) {
289                                 rs->sr_entry = &ent;
290                                 rs->sr_attrs = op->ors_attrs;
291                                 rs->sr_operational_attrs = NULL;
292                                 rs->sr_flags = 0;
293                                 abort = send_search_entry( op, rs );
294                                 if ( !BER_BVISNULL( &ent.e_name ) ) {
295                                         assert( ent.e_name.bv_val != bdn.bv_val );
296                                         free( ent.e_name.bv_val );
297                                         BER_BVZERO( &ent.e_name );
298                                 }
299                                 if ( !BER_BVISNULL( &ent.e_nname ) ) {
300                                         free( ent.e_nname.bv_val );
301                                         BER_BVZERO( &ent.e_nname );
302                                 }
303                                 entry_clean( &ent );
304                         }
305                         ldap_msgfree( res );
306                         if ( abort ) {
307                                 ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
308                                 goto finish;
309                         }
310
311                 } else if ( rc == LDAP_RES_SEARCH_REFERENCE ) {
312                         char            **references = NULL;
313
314                         do_retry = 0;
315                         rc = ldap_parse_reference( lc->lc_ld, res,
316                                         &references, &rs->sr_ctrls, 1 );
317
318                         if ( rc != LDAP_SUCCESS ) {
319                                 continue;
320                         }
321
322                         /* FIXME: there MUST be at least one */
323                         if ( references && references[ 0 ] && references[ 0 ][ 0 ] ) {
324                                 int             cnt;
325
326                                 for ( cnt = 0; references[ cnt ]; cnt++ )
327                                         /* NO OP */ ;
328
329                                 /* FIXME: there MUST be at least one */
330                                 rs->sr_ref = ch_malloc( ( cnt + 1 ) * sizeof( struct berval ) );
331
332                                 for ( cnt = 0; references[ cnt ]; cnt++ ) {
333                                         ber_str2bv( references[ cnt ], 0, 0, &rs->sr_ref[ cnt ] );
334                                 }
335                                 BER_BVZERO( &rs->sr_ref[ cnt ] );
336
337                                 /* ignore return value by now */
338                                 ( void )send_search_reference( op, rs );
339
340                         } else {
341                                 Debug( LDAP_DEBUG_ANY,
342                                         "%s ldap_back_search: "
343                                         "got SEARCH_REFERENCE "
344                                         "with no referrals\n",
345                                         op->o_log_prefix, 0, 0 );
346                         }
347
348                         /* cleanup */
349                         if ( references ) {
350                                 ldap_value_free( references );
351                                 ch_free( rs->sr_ref );
352                                 rs->sr_ref = NULL;
353                         }
354
355                         if ( rs->sr_ctrls ) {
356                                 ldap_controls_free( rs->sr_ctrls );
357                                 rs->sr_ctrls = NULL;
358                         }
359
360                 } else {
361                         char            **references = NULL;
362
363                         rc = ldap_parse_result( lc->lc_ld, res, &rs->sr_err,
364                                         &match.bv_val, (char **)&rs->sr_text,
365                                         &references, &rs->sr_ctrls, 1 );
366                         freetext = 1;
367                         if ( rc != LDAP_SUCCESS ) {
368                                 rs->sr_err = rc;
369                         }
370                         rs->sr_err = slap_map_api2result( rs );
371
372                         if ( references && references[ 0 ] && references[ 0 ][ 0 ] ) {
373                                 int     cnt;
374
375                                 if ( rs->sr_err != LDAP_REFERRAL ) {
376                                         /* FIXME: error */
377                                         Debug( LDAP_DEBUG_ANY,
378                                                 "%s ldap_back_search: "
379                                                 "got referrals with %d\n",
380                                                 op->o_log_prefix,
381                                                 rs->sr_err, 0 );
382                                         rs->sr_err = LDAP_REFERRAL;
383                                 }
384
385                                 for ( cnt = 0; references[ cnt ]; cnt++ )
386                                         /* NO OP */ ;
387                                 
388                                 rs->sr_ref = ch_malloc( ( cnt + 1 ) * sizeof( struct berval ) );
389
390                                 for ( cnt = 0; references[ cnt ]; cnt++ ) {
391                                         /* duplicating ...*/
392                                         ber_str2bv( references[ cnt ], 0, 1, &rs->sr_ref[ cnt ] );
393                                 }
394                                 BER_BVZERO( &rs->sr_ref[ cnt ] );
395                         }
396
397                         /* cleanup */
398                         if ( references ) {
399                                 ldap_value_free( references );
400                         }
401
402                         rc = 0;
403                         break;
404                 }
405         }
406
407         if ( rc == -1 ) {
408                 if ( do_retry ) {
409                         do_retry = 0;
410                         if ( ldap_back_retry( lc, op, rs, LDAP_BACK_SENDERR ) ) {
411                                 goto retry;
412                         }
413                 }
414                 rs->sr_err = LDAP_SERVER_DOWN;
415                 goto fail;
416         }
417
418         /*
419          * Rewrite the matched portion of the search base, if required
420          */
421         if ( !BER_BVISNULL( &match ) && !BER_BVISEMPTY( &match ) ) {
422                 rs->sr_matched = match.bv_val;
423         }
424
425         if ( rs->sr_v2ref ) {
426                 rs->sr_err = LDAP_REFERRAL;
427         }
428
429 finish:;
430         if ( rc != SLAPD_ABANDON ) {
431                 send_ldap_result( op, rs );
432         }
433
434         (void)ldap_back_proxy_authz_ctrl_free( op, &ctrls );
435
436         if ( rs->sr_ctrls ) {
437                 ldap_controls_free( rs->sr_ctrls );
438                 rs->sr_ctrls = NULL;
439         }
440
441         if ( match.bv_val ) {
442                 rs->sr_matched = NULL;
443                 LDAP_FREE( match.bv_val );
444         }
445
446         if ( !BER_BVISNULL( &filter ) && filter.bv_val != op->ors_filterstr.bv_val ) {
447                 op->o_tmpfree( filter.bv_val, op->o_tmpmemctx );
448         }
449
450         if ( rs->sr_text ) {
451                 if ( freetext ) {
452                         LDAP_FREE( (char *)rs->sr_text );
453                 }
454                 rs->sr_text = NULL;
455         }
456
457         if ( rs->sr_ref ) {
458                 ber_bvarray_free( rs->sr_ref );
459                 rs->sr_ref = NULL;
460         }
461
462         if ( attrs ) {
463                 ch_free( attrs );
464         }
465
466         if ( lc != NULL ) {
467                 ldap_back_release_conn( op, rs, lc );
468         }
469
470         return rc;
471 }
472
473 static int
474 ldap_build_entry(
475                 Operation       *op,
476                 LDAPMessage     *e,
477                 Entry           *ent,
478                 struct berval   *bdn )
479 {
480         struct berval   a;
481         BerElement      ber = *e->lm_ber;
482         Attribute       *attr, **attrp;
483         const char      *text;
484         int             last;
485
486         /* safe assumptions ... */
487         assert( ent != NULL );
488         BER_BVZERO( &ent->e_bv );
489
490         if ( ber_scanf( &ber, "{m{", bdn ) == LBER_ERROR ) {
491                 return LDAP_DECODING_ERROR;
492         }
493
494         /*
495          * Note: this may fail if the target host(s) schema differs
496          * from the one known to the meta, and a DN with unknown
497          * attributes is returned.
498          * 
499          * FIXME: should we log anything, or delegate to dnNormalize?
500          */
501         /* Note: if the distinguished values or the naming attributes
502          * change, should we massage them as well?
503          */
504         if ( dnPrettyNormal( NULL, bdn, &ent->e_name, &ent->e_nname,
505                 op->o_tmpmemctx ) != LDAP_SUCCESS )
506         {
507                 return LDAP_INVALID_DN_SYNTAX;
508         }
509
510         attrp = &ent->e_attrs;
511
512         while ( ber_scanf( &ber, "{m", &a ) != LBER_ERROR ) {
513                 int                             i;
514                 slap_syntax_validate_func       *validate;
515                 slap_syntax_transform_func      *pretty;
516
517                 attr = (Attribute *)ch_malloc( sizeof( Attribute ) );
518                 if ( attr == NULL ) {
519                         continue;
520                 }
521                 attr->a_flags = 0;
522                 attr->a_next = 0;
523                 attr->a_desc = NULL;
524                 if ( slap_bv2ad( &a, &attr->a_desc, &text ) 
525                                 != LDAP_SUCCESS )
526                 {
527                         if ( slap_bv2undef_ad( &a, &attr->a_desc, &text ) 
528                                         != LDAP_SUCCESS )
529                         {
530                                 Debug( LDAP_DEBUG_ANY, 
531                                         "slap_bv2undef_ad(%s):  %s\n",
532                                         a.bv_val, text, 0 );
533                                 ch_free( attr );
534                                 continue;
535                         }
536                 }
537
538                 /* no subschemaSubentry */
539                 if ( attr->a_desc == slap_schema.si_ad_subschemaSubentry ) {
540
541                         /* 
542                          * We eat target's subschemaSubentry because
543                          * a search for this value is likely not
544                          * to resolve to the appropriate backend;
545                          * later, the local subschemaSubentry is
546                          * added.
547                          */
548                         ( void )ber_scanf( &ber, "x" /* [W] */ );
549
550                         ch_free( attr );
551                         continue;
552                 }
553                 
554                 if ( ber_scanf( &ber, "[W]", &attr->a_vals ) == LBER_ERROR
555                                 || attr->a_vals == NULL )
556                 {
557                         /*
558                          * Note: attr->a_vals can be null when using
559                          * values result filter
560                          */
561                         attr->a_vals = (struct berval *)&slap_dummy_bv;
562                         last = 0;
563
564                 } else {
565                         for ( last = 0; !BER_BVISNULL( &attr->a_vals[ last ] ); last++ )
566                                 /* just count vals */ ;
567                 }
568
569                 validate = attr->a_desc->ad_type->sat_syntax->ssyn_validate;
570                 pretty = attr->a_desc->ad_type->sat_syntax->ssyn_pretty;
571
572                 if ( !validate && !pretty ) {
573                         attr->a_nvals = NULL;
574                         attr_free( attr );
575                         goto next_attr;
576                 }
577
578                 for ( i = 0; i < last; i++ ) {
579                         struct berval   pval;
580                         int             rc;
581
582                         if ( pretty ) {
583                                 rc = pretty( attr->a_desc->ad_type->sat_syntax,
584                                         &attr->a_vals[i], &pval, NULL );
585
586                         } else {
587                                 rc = validate( attr->a_desc->ad_type->sat_syntax,
588                                         &attr->a_vals[i] );
589                         }
590
591                         if ( rc != LDAP_SUCCESS ) {
592                                 /* check if, by chance, it's an undefined objectClass */
593                                 if ( attr->a_desc == slap_schema.si_ad_objectClass &&
594                                                 oc_bvfind_undef( &attr->a_vals[i] ) != NULL )
595                                 {
596                                         ber_dupbv( &pval, &attr->a_vals[i] );
597
598                                 } else {
599                                         attr->a_nvals = NULL;
600                                         attr_free( attr );
601                                         goto next_attr;
602                                 }
603                         }
604
605                         if ( pretty ) {
606                                 LBER_FREE( attr->a_vals[i].bv_val );
607                                 attr->a_vals[i] = pval;
608                         }
609                 }
610
611                 if ( last && attr->a_desc->ad_type->sat_equality &&
612                                 attr->a_desc->ad_type->sat_equality->smr_normalize )
613                 {
614                         attr->a_nvals = ch_malloc( ( last + 1 )*sizeof( struct berval ) );
615                         for ( i = 0; i < last; i++ ) {
616                                 int             rc;
617
618                                 /*
619                                  * check that each value is valid per syntax
620                                  * and pretty if appropriate
621                                  */
622                                 rc = attr->a_desc->ad_type->sat_equality->smr_normalize(
623                                         SLAP_MR_VALUE_OF_ATTRIBUTE_SYNTAX,
624                                         attr->a_desc->ad_type->sat_syntax,
625                                         attr->a_desc->ad_type->sat_equality,
626                                         &attr->a_vals[i], &attr->a_nvals[i],
627                                         NULL );
628
629                                 if ( rc != LDAP_SUCCESS ) {
630                                         BER_BVZERO( &attr->a_nvals[i] );
631                                         ch_free( attr );
632                                         goto next_attr;
633                                 }
634                         }
635                         BER_BVZERO( &attr->a_nvals[i] );
636
637                 } else {
638                         attr->a_nvals = attr->a_vals;
639                 }
640                 *attrp = attr;
641                 attrp = &attr->a_next;
642
643 next_attr:;
644         }
645
646         return LDAP_SUCCESS;
647 }
648
649 /* return 0 IFF we can retrieve the entry with ndn
650  */
651 int
652 ldap_back_entry_get(
653                 Operation               *op,
654                 struct berval           *ndn,
655                 ObjectClass             *oc,
656                 AttributeDescription    *at,
657                 int                     rw,
658                 Entry                   **ent
659 )
660 {
661         struct ldapconn *lc;
662         int             rc = 1,
663                         do_not_cache;
664         struct berval   bdn;
665         LDAPMessage     *result = NULL,
666                         *e = NULL;
667         char            *gattr[3];
668         char            *filter = NULL;
669         SlapReply       rs;
670         int             do_retry = 1;
671         LDAPControl     **ctrls = NULL;
672
673         /* Tell getconn this is a privileged op */
674         do_not_cache = op->o_do_not_cache;
675         op->o_do_not_cache = 1;
676         lc = ldap_back_getconn( op, &rs, LDAP_BACK_DONTSEND );
677         if ( !lc || !ldap_back_dobind( lc, op, &rs, LDAP_BACK_DONTSEND ) ) {
678                 op->o_do_not_cache = do_not_cache;
679                 return rs.sr_err;
680         }
681         op->o_do_not_cache = do_not_cache;
682
683         if ( at ) {
684                 if ( oc && at != slap_schema.si_ad_objectClass ) {
685                         gattr[0] = slap_schema.si_ad_objectClass->ad_cname.bv_val;
686                         gattr[1] = at->ad_cname.bv_val;
687                         gattr[2] = NULL;
688
689                 } else {
690                         gattr[0] = at->ad_cname.bv_val;
691                         gattr[1] = NULL;
692                 }
693         }
694
695         if ( oc ) {
696                 char    *ptr;
697
698                 filter = ch_malloc( STRLENOF( "(objectclass=)" ) 
699                                 + oc->soc_cname.bv_len + 1 );
700                 ptr = lutil_strcopy( filter, "(objectclass=" );
701                 ptr = lutil_strcopy( ptr, oc->soc_cname.bv_val );
702                 *ptr++ = ')';
703                 *ptr++ = '\0';
704         }
705
706         ctrls = op->o_ctrls;
707         rc = ldap_back_proxy_authz_ctrl( lc, op, &rs, &ctrls );
708         if ( rc != LDAP_SUCCESS ) {
709                 goto cleanup;
710         }
711         
712 retry:
713         rc = ldap_search_ext_s( lc->lc_ld, ndn->bv_val, LDAP_SCOPE_BASE, filter,
714                                 at ? gattr : NULL, 0, ctrls, NULL,
715                                 LDAP_NO_LIMIT, LDAP_NO_LIMIT, &result );
716         if ( rc != LDAP_SUCCESS ) {
717                 if ( rc == LDAP_SERVER_DOWN && do_retry ) {
718                         do_retry = 0;
719                         if ( ldap_back_retry( lc, op, &rs, LDAP_BACK_DONTSEND ) ) {
720                                 goto retry;
721                         }
722                 }
723                 goto cleanup;
724         }
725
726         e = ldap_first_entry( lc->lc_ld, result );
727         if ( e == NULL ) {
728                 goto cleanup;
729         }
730
731         *ent = ch_calloc( 1, sizeof( Entry ) );
732
733         rc = ldap_build_entry( op, e, *ent, &bdn );
734
735         if ( rc != LDAP_SUCCESS ) {
736                 ch_free( *ent );
737                 *ent = NULL;
738         }
739
740 cleanup:
741         (void)ldap_back_proxy_authz_ctrl_free( op, &ctrls );
742
743         if ( result ) {
744                 ldap_msgfree( result );
745         }
746
747         if ( filter ) {
748                 ch_free( filter );
749         }
750
751         if ( lc != NULL ) {
752                 ldap_back_release_conn( op, &rs, lc );
753         }
754
755         return rc;
756 }
757