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add a giant mutex around the ldapinfo structure to serialize chaining (need to check...
[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                 LDAP_BACK_TV_SET( &tv );
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                         LDAP_BACK_TV_SET( &tv );
267                         ldap_pvt_thread_yield();
268
269                         /* check time limit */
270                         if ( op->ors_tlimit != SLAP_NO_LIMIT
271                                         && slap_get_time() > stoptime )
272                         {
273                                 ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
274                                 rc = rs->sr_err = LDAP_TIMELIMIT_EXCEEDED;
275                                 goto finish;
276                         }
277
278                 } else if ( rc == LDAP_RES_SEARCH_ENTRY ) {
279                         Entry           ent = { 0 };
280                         struct berval   bdn = BER_BVNULL;
281                         int             abort = 0;
282
283                         do_retry = 0;
284
285                         e = ldap_first_entry( lc->lc_ld, res );
286                         rc = ldap_build_entry( op, e, &ent, &bdn );
287                         if ( rc == LDAP_SUCCESS ) {
288                                 rs->sr_entry = &ent;
289                                 rs->sr_attrs = op->ors_attrs;
290                                 rs->sr_operational_attrs = NULL;
291                                 rs->sr_flags = 0;
292                                 abort = send_search_entry( op, rs );
293                                 if ( !BER_BVISNULL( &ent.e_name ) ) {
294                                         assert( ent.e_name.bv_val != bdn.bv_val );
295                                         free( ent.e_name.bv_val );
296                                         BER_BVZERO( &ent.e_name );
297                                 }
298                                 if ( !BER_BVISNULL( &ent.e_nname ) ) {
299                                         free( ent.e_nname.bv_val );
300                                         BER_BVZERO( &ent.e_nname );
301                                 }
302                                 entry_clean( &ent );
303                         }
304                         ldap_msgfree( res );
305                         if ( abort ) {
306                                 ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
307                                 goto finish;
308                         }
309
310                 } else if ( rc == LDAP_RES_SEARCH_REFERENCE ) {
311                         char            **references = NULL;
312
313                         do_retry = 0;
314                         rc = ldap_parse_reference( lc->lc_ld, res,
315                                         &references, &rs->sr_ctrls, 1 );
316
317                         if ( rc != LDAP_SUCCESS ) {
318                                 continue;
319                         }
320
321                         /* FIXME: there MUST be at least one */
322                         if ( references && references[ 0 ] && references[ 0 ][ 0 ] ) {
323                                 int             cnt;
324
325                                 for ( cnt = 0; references[ cnt ]; cnt++ )
326                                         /* NO OP */ ;
327
328                                 /* FIXME: there MUST be at least one */
329                                 rs->sr_ref = ch_malloc( ( cnt + 1 ) * sizeof( struct berval ) );
330
331                                 for ( cnt = 0; references[ cnt ]; cnt++ ) {
332                                         ber_str2bv( references[ cnt ], 0, 0, &rs->sr_ref[ cnt ] );
333                                 }
334                                 BER_BVZERO( &rs->sr_ref[ cnt ] );
335
336                                 /* ignore return value by now */
337                                 ( void )send_search_reference( op, rs );
338
339                         } else {
340                                 Debug( LDAP_DEBUG_ANY,
341                                         "%s ldap_back_search: "
342                                         "got SEARCH_REFERENCE "
343                                         "with no referrals\n",
344                                         op->o_log_prefix, 0, 0 );
345                         }
346
347                         /* cleanup */
348                         if ( references ) {
349                                 ldap_value_free( references );
350                                 ch_free( rs->sr_ref );
351                                 rs->sr_ref = NULL;
352                         }
353
354                         if ( rs->sr_ctrls ) {
355                                 ldap_controls_free( rs->sr_ctrls );
356                                 rs->sr_ctrls = NULL;
357                         }
358
359                 } else {
360                         char            **references = NULL;
361
362                         rc = ldap_parse_result( lc->lc_ld, res, &rs->sr_err,
363                                         &match.bv_val, (char **)&rs->sr_text,
364                                         &references, &rs->sr_ctrls, 1 );
365                         freetext = 1;
366                         if ( rc != LDAP_SUCCESS ) {
367                                 rs->sr_err = rc;
368                         }
369                         rs->sr_err = slap_map_api2result( rs );
370
371                         if ( references && references[ 0 ] && references[ 0 ][ 0 ] ) {
372                                 int     cnt;
373
374                                 if ( rs->sr_err != LDAP_REFERRAL ) {
375                                         /* FIXME: error */
376                                         Debug( LDAP_DEBUG_ANY,
377                                                 "%s ldap_back_search: "
378                                                 "got referrals with %d\n",
379                                                 op->o_log_prefix,
380                                                 rs->sr_err, 0 );
381                                         rs->sr_err = LDAP_REFERRAL;
382                                 }
383
384                                 for ( cnt = 0; references[ cnt ]; cnt++ )
385                                         /* NO OP */ ;
386                                 
387                                 rs->sr_ref = ch_malloc( ( cnt + 1 ) * sizeof( struct berval ) );
388
389                                 for ( cnt = 0; references[ cnt ]; cnt++ ) {
390                                         /* duplicating ...*/
391                                         ber_str2bv( references[ cnt ], 0, 1, &rs->sr_ref[ cnt ] );
392                                 }
393                                 BER_BVZERO( &rs->sr_ref[ cnt ] );
394                         }
395
396                         if ( match.bv_val != NULL ) {
397                                 if ( match.bv_val[ 0 ] == '\0' ) {
398                                         LDAP_FREE( match.bv_val );
399                                         BER_BVZERO( &match );
400                                 } else {
401                                         match.bv_len = strlen( match.bv_val );
402                                 }
403                         }
404
405                         /* cleanup */
406                         if ( references ) {
407                                 ldap_value_free( references );
408                         }
409
410                         rc = 0;
411                         break;
412                 }
413         }
414
415         if ( rc == -1 ) {
416                 if ( do_retry ) {
417                         do_retry = 0;
418                         if ( ldap_back_retry( lc, op, rs, LDAP_BACK_SENDERR ) ) {
419                                 goto retry;
420                         }
421                 }
422                 rs->sr_err = LDAP_SERVER_DOWN;
423                 goto fail;
424         }
425
426         /*
427          * Rewrite the matched portion of the search base, if required
428          */
429         if ( !BER_BVISNULL( &match ) && !BER_BVISEMPTY( &match ) ) {
430                 struct berval   pmatch;
431
432                 if ( dnPretty( NULL, &match, &pmatch, op->o_tmpmemctx ) == LDAP_SUCCESS ) {
433                         rs->sr_matched = pmatch.bv_val;
434                         LDAP_FREE( match.bv_val );
435
436                 } else {
437                         rs->sr_matched = match.bv_val;
438                 }
439         }
440
441         if ( rs->sr_v2ref ) {
442                 rs->sr_err = LDAP_REFERRAL;
443         }
444
445 finish:;
446         if ( rc != SLAPD_ABANDON ) {
447                 send_ldap_result( op, rs );
448         }
449
450         (void)ldap_back_proxy_authz_ctrl_free( op, &ctrls );
451
452         if ( rs->sr_ctrls ) {
453                 ldap_controls_free( rs->sr_ctrls );
454                 rs->sr_ctrls = NULL;
455         }
456
457         if ( rs->sr_matched != NULL ) {
458                 if ( rs->sr_matched != match.bv_val ) {
459                         ber_memfree_x( (char *)rs->sr_matched, op->o_tmpmemctx );
460
461                 } else {
462                         LDAP_FREE( match.bv_val );
463                 }
464                 rs->sr_matched = NULL;
465         }
466
467         if ( !BER_BVISNULL( &filter ) && filter.bv_val != op->ors_filterstr.bv_val ) {
468                 op->o_tmpfree( filter.bv_val, op->o_tmpmemctx );
469         }
470
471         if ( rs->sr_text ) {
472                 if ( freetext ) {
473                         LDAP_FREE( (char *)rs->sr_text );
474                 }
475                 rs->sr_text = NULL;
476         }
477
478         if ( rs->sr_ref ) {
479                 ber_bvarray_free( rs->sr_ref );
480                 rs->sr_ref = NULL;
481         }
482
483         if ( attrs ) {
484                 ch_free( attrs );
485         }
486
487         if ( lc != NULL ) {
488                 ldap_back_release_conn( op, rs, lc );
489         }
490
491         return rs->sr_err;
492 }
493
494 static int
495 ldap_build_entry(
496                 Operation       *op,
497                 LDAPMessage     *e,
498                 Entry           *ent,
499                 struct berval   *bdn )
500 {
501         struct berval   a;
502         BerElement      ber = *e->lm_ber;
503         Attribute       *attr, **attrp;
504         const char      *text;
505         int             last;
506
507         /* safe assumptions ... */
508         assert( ent != NULL );
509         BER_BVZERO( &ent->e_bv );
510
511         if ( ber_scanf( &ber, "{m{", bdn ) == LBER_ERROR ) {
512                 return LDAP_DECODING_ERROR;
513         }
514
515         /*
516          * Note: this may fail if the target host(s) schema differs
517          * from the one known to the meta, and a DN with unknown
518          * attributes is returned.
519          * 
520          * FIXME: should we log anything, or delegate to dnNormalize?
521          */
522         /* Note: if the distinguished values or the naming attributes
523          * change, should we massage them as well?
524          */
525         if ( dnPrettyNormal( NULL, bdn, &ent->e_name, &ent->e_nname,
526                 op->o_tmpmemctx ) != LDAP_SUCCESS )
527         {
528                 return LDAP_INVALID_DN_SYNTAX;
529         }
530
531         attrp = &ent->e_attrs;
532
533         while ( ber_scanf( &ber, "{m", &a ) != LBER_ERROR ) {
534                 int                             i;
535                 slap_syntax_validate_func       *validate;
536                 slap_syntax_transform_func      *pretty;
537
538                 attr = (Attribute *)ch_malloc( sizeof( Attribute ) );
539                 if ( attr == NULL ) {
540                         continue;
541                 }
542                 attr->a_flags = 0;
543                 attr->a_next = 0;
544                 attr->a_desc = NULL;
545                 if ( slap_bv2ad( &a, &attr->a_desc, &text ) 
546                                 != LDAP_SUCCESS )
547                 {
548                         if ( slap_bv2undef_ad( &a, &attr->a_desc, &text,
549                                 SLAP_AD_PROXIED ) != LDAP_SUCCESS )
550                         {
551                                 Debug( LDAP_DEBUG_ANY, 
552                                         "%s ldap_build_entry: "
553                                         "slap_bv2undef_ad(%s): %s\n",
554                                         op->o_log_prefix, a.bv_val, text );
555                                 ch_free( attr );
556                                 continue;
557                         }
558                 }
559
560                 /* no subschemaSubentry */
561                 if ( attr->a_desc == slap_schema.si_ad_subschemaSubentry
562                         || attr->a_desc == slap_schema.si_ad_entryDN )
563                 {
564
565                         /* 
566                          * We eat target's subschemaSubentry because
567                          * a search for this value is likely not
568                          * to resolve to the appropriate backend;
569                          * later, the local subschemaSubentry is
570                          * added.
571                          *
572                          * We also eat entryDN because the frontend
573                          * will reattach it without checking if already
574                          * present...
575                          */
576                         ( void )ber_scanf( &ber, "x" /* [W] */ );
577
578                         ch_free( attr );
579                         continue;
580                 }
581                 
582                 if ( ber_scanf( &ber, "[W]", &attr->a_vals ) == LBER_ERROR
583                                 || attr->a_vals == NULL )
584                 {
585                         /*
586                          * Note: attr->a_vals can be null when using
587                          * values result filter
588                          */
589                         attr->a_vals = (struct berval *)&slap_dummy_bv;
590                         last = 0;
591
592                 } else {
593                         for ( last = 0; !BER_BVISNULL( &attr->a_vals[ last ] ); last++ )
594                                 /* just count vals */ ;
595                 }
596
597                 validate = attr->a_desc->ad_type->sat_syntax->ssyn_validate;
598                 pretty = attr->a_desc->ad_type->sat_syntax->ssyn_pretty;
599
600                 if ( !validate && !pretty ) {
601                         attr->a_nvals = NULL;
602                         attr_free( attr );
603                         goto next_attr;
604                 }
605
606                 for ( i = 0; i < last; i++ ) {
607                         struct berval   pval;
608                         int             rc;
609
610                         if ( pretty ) {
611                                 rc = pretty( attr->a_desc->ad_type->sat_syntax,
612                                         &attr->a_vals[i], &pval, NULL );
613
614                         } else {
615                                 rc = validate( attr->a_desc->ad_type->sat_syntax,
616                                         &attr->a_vals[i] );
617                         }
618
619                         if ( rc != LDAP_SUCCESS ) {
620                                 /* check if, by chance, it's an undefined objectClass */
621                                 if ( attr->a_desc == slap_schema.si_ad_objectClass &&
622                                                 oc_bvfind_undef( &attr->a_vals[i] ) != NULL )
623                                 {
624                                         ber_dupbv( &pval, &attr->a_vals[i] );
625
626                                 } else {
627                                         attr->a_nvals = NULL;
628                                         attr_free( attr );
629                                         goto next_attr;
630                                 }
631                         }
632
633                         if ( pretty ) {
634                                 LBER_FREE( attr->a_vals[i].bv_val );
635                                 attr->a_vals[i] = pval;
636                         }
637                 }
638
639                 if ( last && attr->a_desc->ad_type->sat_equality &&
640                                 attr->a_desc->ad_type->sat_equality->smr_normalize )
641                 {
642                         attr->a_nvals = ch_malloc( ( last + 1 )*sizeof( struct berval ) );
643                         for ( i = 0; i < last; i++ ) {
644                                 int             rc;
645
646                                 /*
647                                  * check that each value is valid per syntax
648                                  * and pretty if appropriate
649                                  */
650                                 rc = attr->a_desc->ad_type->sat_equality->smr_normalize(
651                                         SLAP_MR_VALUE_OF_ATTRIBUTE_SYNTAX,
652                                         attr->a_desc->ad_type->sat_syntax,
653                                         attr->a_desc->ad_type->sat_equality,
654                                         &attr->a_vals[i], &attr->a_nvals[i],
655                                         NULL );
656
657                                 if ( rc != LDAP_SUCCESS ) {
658                                         BER_BVZERO( &attr->a_nvals[i] );
659                                         ch_free( attr );
660                                         goto next_attr;
661                                 }
662                         }
663                         BER_BVZERO( &attr->a_nvals[i] );
664
665                 } else {
666                         attr->a_nvals = attr->a_vals;
667                 }
668                 *attrp = attr;
669                 attrp = &attr->a_next;
670
671 next_attr:;
672         }
673
674         return LDAP_SUCCESS;
675 }
676
677 /* return 0 IFF we can retrieve the entry with ndn
678  */
679 int
680 ldap_back_entry_get(
681                 Operation               *op,
682                 struct berval           *ndn,
683                 ObjectClass             *oc,
684                 AttributeDescription    *at,
685                 int                     rw,
686                 Entry                   **ent
687 )
688 {
689         struct ldapconn *lc;
690         int             rc = 1,
691                         do_not_cache;
692         struct berval   bdn;
693         LDAPMessage     *result = NULL,
694                         *e = NULL;
695         char            *gattr[3];
696         char            *filter = NULL;
697         SlapReply       rs;
698         int             do_retry = 1;
699         LDAPControl     **ctrls = NULL;
700
701         /* Tell getconn this is a privileged op */
702         do_not_cache = op->o_do_not_cache;
703         op->o_do_not_cache = 1;
704         lc = ldap_back_getconn( op, &rs, LDAP_BACK_DONTSEND );
705         if ( !lc || !ldap_back_dobind( lc, op, &rs, LDAP_BACK_DONTSEND ) ) {
706                 op->o_do_not_cache = do_not_cache;
707                 return rs.sr_err;
708         }
709         op->o_do_not_cache = do_not_cache;
710
711         if ( at ) {
712                 if ( oc && at != slap_schema.si_ad_objectClass ) {
713                         gattr[0] = slap_schema.si_ad_objectClass->ad_cname.bv_val;
714                         gattr[1] = at->ad_cname.bv_val;
715                         gattr[2] = NULL;
716
717                 } else {
718                         gattr[0] = at->ad_cname.bv_val;
719                         gattr[1] = NULL;
720                 }
721         }
722
723         if ( oc ) {
724                 char    *ptr;
725
726                 filter = ch_malloc( STRLENOF( "(objectclass=)" ) 
727                                 + oc->soc_cname.bv_len + 1 );
728                 ptr = lutil_strcopy( filter, "(objectclass=" );
729                 ptr = lutil_strcopy( ptr, oc->soc_cname.bv_val );
730                 *ptr++ = ')';
731                 *ptr++ = '\0';
732         }
733
734         ctrls = op->o_ctrls;
735         rc = ldap_back_proxy_authz_ctrl( lc, op, &rs, &ctrls );
736         if ( rc != LDAP_SUCCESS ) {
737                 goto cleanup;
738         }
739         
740 retry:
741         rc = ldap_search_ext_s( lc->lc_ld, ndn->bv_val, LDAP_SCOPE_BASE, filter,
742                                 at ? gattr : NULL, 0, ctrls, NULL,
743                                 LDAP_NO_LIMIT, LDAP_NO_LIMIT, &result );
744         if ( rc != LDAP_SUCCESS ) {
745                 if ( rc == LDAP_SERVER_DOWN && do_retry ) {
746                         do_retry = 0;
747                         if ( ldap_back_retry( lc, op, &rs, LDAP_BACK_DONTSEND ) ) {
748                                 goto retry;
749                         }
750                 }
751                 goto cleanup;
752         }
753
754         e = ldap_first_entry( lc->lc_ld, result );
755         if ( e == NULL ) {
756                 goto cleanup;
757         }
758
759         *ent = ch_calloc( 1, sizeof( Entry ) );
760
761         rc = ldap_build_entry( op, e, *ent, &bdn );
762
763         if ( rc != LDAP_SUCCESS ) {
764                 ch_free( *ent );
765                 *ent = NULL;
766         }
767
768 cleanup:
769         (void)ldap_back_proxy_authz_ctrl_free( op, &ctrls );
770
771         if ( result ) {
772                 ldap_msgfree( result );
773         }
774
775         if ( filter ) {
776                 ch_free( filter );
777         }
778
779         if ( lc != NULL ) {
780                 ldap_back_release_conn( op, &rs, lc );
781         }
782
783         return rc;
784 }
785