]> git.sur5r.net Git - openldap/blobdiff - servers/slapd/back-meta/conn.c
Merge remote-tracking branch 'origin/mdb.master' into OPENLDAP_REL_ENG_2_4
[openldap] / servers / slapd / back-meta / conn.c
index 58d727d44c55465942aec0f933b197d041d17bd4..7e63fae89604e8b031dd868addb8bf5378b96c71 100644 (file)
@@ -1,7 +1,7 @@
 /* $OpenLDAP$ */
 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
  *
- * Copyright 1999-2006 The OpenLDAP Foundation.
+ * Copyright 1999-2013 The OpenLDAP Foundation.
  * Portions Copyright 2001-2003 Pierangelo Masarati.
  * Portions Copyright 1999-2003 Howard Chu.
  * All rights reserved.
 #include "../back-ldap/back-ldap.h"
 #include "back-meta.h"
 
-/*
- * Set PRINT_CONNTREE larger than 0 to dump the connection tree (debug only)
- */
-#ifndef PRINT_CONNTREE
-#define PRINT_CONNTREE 0
-#endif /* !PRINT_CONNTREE */
-
 /*
  * meta_back_conndn_cmp
  *
@@ -145,48 +138,91 @@ meta_back_conndn_dup(
 /*
  * Debug stuff (got it from libavl)
  */
-#if PRINT_CONNTREE > 0
+#if META_BACK_PRINT_CONNTREE > 0
+static void
+meta_back_print( metaconn_t *mc, char *avlstr )
+{
+       int     i;
+
+       fputs( "targets=[", stderr );
+       for ( i = 0; i < mc->mc_info->mi_ntargets; i++ ) {
+               fputc( mc->mc_conns[ i ].msc_ld ? '*' : 'o', stderr);
+       }
+       fputc( ']', stderr );
+
+       fprintf( stderr, " mc=%p local=\"%s\" conn=%p refcnt=%d%s %s\n",
+               (void *)mc,
+               mc->mc_local_ndn.bv_val ? mc->mc_local_ndn.bv_val : "",
+               (void *)mc->mc_conn,
+               mc->mc_refcnt,
+               LDAP_BACK_CONN_TAINTED( mc ) ? " tainted" : "",
+               avlstr );
+}
+
 static void
-ravl_print( Avlnode *root, int depth )
+meta_back_ravl_print( Avlnode *root, int depth )
 {
        int             i;
-       metaconn_t      *mc;
-       
+
        if ( root == 0 ) {
                return;
        }
        
-       ravl_print( root->avl_right, depth + 1 );
+       meta_back_ravl_print( root->avl_right, depth + 1 );
        
        for ( i = 0; i < depth; i++ ) {
                fprintf( stderr, "-" );
        }
+       fputc( ' ', stderr );
 
-       mc = (metaconn_t *)root->avl_data;
-       fprintf( stderr, "mc=%p local=\"%s\" conn=%p %s refcnt=%d\n",
-               (void *)mc,
-               mc->mc_local_ndn.bv_val ? mc->mc_local_ndn.bv_val : "",
-               (void *)mc->mc_conn,
-               avl_bf2str( root->avl_bf ), mc->mc_refcnt );
-       
-       ravl_print( root->avl_left, depth + 1 );
+       meta_back_print( (metaconn_t *)root->avl_data,
+               avl_bf2str( root->avl_bf ) );
+
+       meta_back_ravl_print( root->avl_left, depth + 1 );
 }
 
-static void
-myprint( Avlnode *root, char *msg )
+/* NOTE: duplicate from back-ldap/bind.c */
+static char* priv2str[] = {
+       "privileged",
+       "privileged/TLS",
+       "anonymous",
+       "anonymous/TLS",
+       "bind",
+       "bind/TLS",
+       NULL
+};
+
+void
+meta_back_print_conntree( metainfo_t *mi, char *msg )
 {
+       int     c;
+
        fprintf( stderr, "========> %s\n", msg );
        
-       if ( root == 0 ) {
-               fprintf( stderr, "\tNULL\n" );
+       for ( c = LDAP_BACK_PCONN_FIRST; c < LDAP_BACK_PCONN_LAST; c++ ) {
+               int             i = 0;
+               metaconn_t      *mc;
+
+               fprintf( stderr, "  %s[%d]\n", priv2str[ c ], mi->mi_conn_priv[ c ].mic_num );
+
+               LDAP_TAILQ_FOREACH( mc, &mi->mi_conn_priv[ c ].mic_priv, mc_q )
+               {
+                       fprintf( stderr, "    [%d] ", i );
+                       meta_back_print( mc, "" );
+                       i++;
+               }
+       }
+       
+       if ( mi->mi_conninfo.lai_tree == NULL ) {
+               fprintf( stderr, "\t(empty)\n" );
 
        } else {
-               ravl_print( root, 0 );
+               meta_back_ravl_print( mi->mi_conninfo.lai_tree, 0 );
        }
        
        fprintf( stderr, "<======== %s\n", msg );
 }
-#endif /* PRINT_CONNTREE */
+#endif /* META_BACK_PRINT_CONNTREE */
 /*
  * End of debug stuff
  */
@@ -202,20 +238,18 @@ metaconn_alloc(
 {
        metainfo_t      *mi = ( metainfo_t * )op->o_bd->be_private;
        metaconn_t      *mc;
-       int             i, ntargets = mi->mi_ntargets;
+       int             ntargets = mi->mi_ntargets;
 
        assert( ntargets > 0 );
 
        /* malloc all in one */
        mc = ( metaconn_t * )ch_calloc( 1, sizeof( metaconn_t )
-                       + sizeof( metasingleconn_t ) * ntargets );
+               + sizeof( metasingleconn_t ) * ( ntargets - 1 ) );
        if ( mc == NULL ) {
                return NULL;
        }
 
-       for ( i = 0; i < ntargets; i++ ) {
-               mc->mc_conns[ i ].msc_info = mi;
-       }
+       mc->mc_info = mi;
 
        mc->mc_authz_target = META_BOUND_NONE;
        mc->mc_refcnt = 1;
@@ -235,7 +269,8 @@ meta_back_init_one_conn(
        metaconn_t              *mc,
        int                     candidate,
        int                     ispriv,
-       ldap_back_send_t        sendok )
+       ldap_back_send_t        sendok,
+       int                     dolock )
 {
        metainfo_t              *mi = ( metainfo_t * )op->o_bd->be_private;
        metatarget_t            *mt = mi->mi_targets[ candidate ];
@@ -243,8 +278,10 @@ meta_back_init_one_conn(
        int                     version;
        dncookie                dc;
        int                     isauthz = ( candidate == mc->mc_authz_target );
+       int                     do_return = 0;
 #ifdef HAVE_TLS
        int                     is_ldaps = 0;
+       int                     do_start_tls = 0;
 #endif /* HAVE_TLS */
 
        /* if the server is quarantined, and
@@ -253,44 +290,103 @@ meta_back_init_one_conn(
         * don't return the connection */
        if ( mt->mt_isquarantined ) {
                slap_retry_info_t       *ri = &mt->mt_quarantine;
-               int                     dont_retry = 1;
+               int                     dont_retry = 0;
+
+               if ( mt->mt_quarantine.ri_interval ) {
+                       ldap_pvt_thread_mutex_lock( &mt->mt_quarantine_mutex );
+                       dont_retry = ( mt->mt_isquarantined > LDAP_BACK_FQ_NO );
+                       if ( dont_retry ) {
+                               dont_retry = ( ri->ri_num[ ri->ri_idx ] == SLAP_RETRYNUM_TAIL
+                                       || slap_get_time() < ri->ri_last + ri->ri_interval[ ri->ri_idx ] );
+                               if ( !dont_retry ) {
+                                       if ( LogTest( LDAP_DEBUG_ANY ) ) {
+                                               char    buf[ SLAP_TEXT_BUFLEN ];
+
+                                               snprintf( buf, sizeof( buf ),
+                                                       "meta_back_init_one_conn[%d]: quarantine "
+                                                       "retry block #%d try #%d",
+                                                       candidate, ri->ri_idx, ri->ri_count );
+                                               Debug( LDAP_DEBUG_ANY, "%s %s.\n",
+                                                       op->o_log_prefix, buf, 0 );
+                                       }
 
-               if ( mt->mt_isquarantined == LDAP_BACK_FQ_YES ) {
-                       dont_retry = ( ri->ri_num[ ri->ri_idx ] == SLAP_RETRYNUM_TAIL
-                               || slap_get_time() < ri->ri_last + ri->ri_interval[ ri->ri_idx ] );
-                       if ( !dont_retry ) {
-                               if ( LogTest( LDAP_DEBUG_ANY ) ) {
-                                       char    buf[ SLAP_TEXT_BUFLEN ];
-
-                                       snprintf( buf, sizeof( buf ),
-                                               "meta_back_init_one_conn[%d]: quarantine "
-                                               "retry block #%d try #%d",
-                                               candidate, ri->ri_idx, ri->ri_count );
-                                       Debug( LDAP_DEBUG_ANY, "%s %s.\n",
-                                               op->o_log_prefix, buf, 0 );
+                                       mt->mt_isquarantined = LDAP_BACK_FQ_RETRYING;
                                }
 
-                               mt->mt_isquarantined = LDAP_BACK_FQ_RETRYING;
                        }
+                       ldap_pvt_thread_mutex_unlock( &mt->mt_quarantine_mutex );
                }
 
                if ( dont_retry ) {
                        rs->sr_err = LDAP_UNAVAILABLE;
                        if ( op->o_conn && ( sendok & LDAP_BACK_SENDERR ) ) {
+                               rs->sr_text = "Target is quarantined";
                                send_ldap_result( op, rs );
                        }
                        return rs->sr_err;
                }
        }
 
+retry_lock:;
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_lock( &mi->mi_conninfo.lai_mutex );
+       }
+
        /*
         * Already init'ed
         */
-       if ( msc->msc_ld != NULL ) {
-               return rs->sr_err = LDAP_SUCCESS;
+       if ( LDAP_BACK_CONN_ISBOUND( msc )
+               || LDAP_BACK_CONN_ISANON( msc ) )
+       {
+               assert( msc->msc_ld != NULL );
+               rs->sr_err = LDAP_SUCCESS;
+               do_return = 1;
+
+       } else if ( META_BACK_CONN_CREATING( msc )
+               || LDAP_BACK_CONN_BINDING( msc ) )
+       {
+               if ( !LDAP_BACK_USE_TEMPORARIES( mi ) ) {
+                       if ( dolock ) {
+                               ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
+                       }
+
+                       ldap_pvt_thread_yield();
+                       goto retry_lock;
+               }
+
+               /* sounds more appropriate */
+               rs->sr_err = LDAP_BUSY;
+               rs->sr_text = "No connections to target are available";
+               do_return = 1;
+
+       } else if ( META_BACK_CONN_INITED( msc ) ) {
+               assert( msc->msc_ld != NULL );
+               rs->sr_err = LDAP_SUCCESS;
+               do_return = 1;
+
+       } else {
+               /*
+                * creating...
+                */
+               META_BACK_CONN_CREATING_SET( msc );
+       }
+
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
+       }
+
+       if ( do_return ) {
+               if ( rs->sr_err != LDAP_SUCCESS
+                       && op->o_conn
+                       && ( sendok & LDAP_BACK_SENDERR ) )
+               {
+                       send_ldap_result( op, rs );
+               }
+
+               return rs->sr_err;
        }
 
-       msc->msc_mscflags = 0;
+       assert( msc->msc_ld == NULL );
        
        /*
         * Attempts to initialize the connection to the target ds
@@ -323,13 +419,38 @@ meta_back_init_one_conn(
 
        /* automatically chase referrals ("chase-referrals [{yes|no}]" statement) */
        ldap_set_option( msc->msc_ld, LDAP_OPT_REFERRALS,
-               LDAP_BACK_CHASE_REFERRALS( mi ) ? LDAP_OPT_ON : LDAP_OPT_OFF );
+               META_BACK_TGT_CHASE_REFERRALS( mt ) ? LDAP_OPT_ON : LDAP_OPT_OFF );
+
+       slap_client_keepalive(msc->msc_ld, &mt->mt_tls.sb_keepalive);
 
 #ifdef HAVE_TLS
+       if ( !is_ldaps ) {
+               slap_bindconf *sb = NULL;
+
+               if ( ispriv ) {
+                       sb = &mt->mt_idassert.si_bc;
+               } else {
+                       sb = &mt->mt_tls;
+               }
+
+               if ( sb->sb_tls_do_init ) {
+                       bindconf_tls_set( sb, msc->msc_ld );
+               } else if ( sb->sb_tls_ctx ) {
+                       ldap_set_option( msc->msc_ld, LDAP_OPT_X_TLS_CTX, sb->sb_tls_ctx );
+               }
+
+               if ( sb == &mt->mt_idassert.si_bc && sb->sb_tls_ctx ) {
+                       do_start_tls = 1;
+
+               } else if ( META_BACK_TGT_USE_TLS( mt )
+                       || ( op->o_conn->c_is_tls && META_BACK_TGT_PROPAGATE_TLS( mt ) ) )
+               {
+                       do_start_tls = 1;
+               }
+       }
+
        /* start TLS ("tls [try-]{start|propagate}" statement) */
-       if ( ( LDAP_BACK_USE_TLS( mi ) || ( op->o_conn->c_is_tls && LDAP_BACK_PROPAGATE_TLS( mi ) ) )
-                       && !is_ldaps )
-       {
+       if ( do_start_tls ) {
 #ifdef SLAP_STARTTLS_ASYNCHRONOUS
                /*
                 * use asynchronous StartTLS; in case, chase referral
@@ -347,10 +468,12 @@ meta_back_init_one_conn(
 
 retry:;
                        rc = ldap_result( msc->msc_ld, msgid, LDAP_MSG_ALL, &tv, &res );
-                       if ( rc < 0 ) {
+                       switch ( rc ) {
+                       case -1:
                                rs->sr_err = LDAP_OTHER;
+                               break;
 
-                       } else if ( rc == 0 ) {
+                       case 0:
                                if ( nretries != 0 ) {
                                        if ( nretries > 0 ) {
                                                nretries--;
@@ -359,23 +482,34 @@ retry:;
                                        goto retry;
                                }
                                rs->sr_err = LDAP_OTHER;
+                               break;
+
+                       default:
+                               /* only touch when activity actually took place... */
+                               if ( mi->mi_idle_timeout != 0 && msc->msc_time < op->o_time ) {
+                                       msc->msc_time = op->o_time;
+                               }
+                               break;
+                       }
 
-                       } else if ( rc == LDAP_RES_EXTENDED ) {
+                       if ( rc == LDAP_RES_EXTENDED ) {
                                struct berval   *data = NULL;
 
-                               rs->sr_err = ldap_parse_extended_result( msc->msc_ld, res,
-                                               NULL, &data, 0 );
+                               /* NOTE: right now, data is unused, so don't get it */
+                               rs->sr_err = ldap_parse_extended_result( msc->msc_ld,
+                                       res, NULL, NULL /* &data */ , 0 );
                                if ( rs->sr_err == LDAP_SUCCESS ) {
                                        int             err;
 
                                        /* FIXME: matched? referrals? response controls? */
-                                       rs->sr_err = ldap_parse_result( msc->msc_ld, res,
-                                               &err, NULL, NULL, NULL, NULL, 1 );
+                                       rs->sr_err = ldap_parse_result( msc->msc_ld,
+                                               res, &err, NULL, NULL, NULL, NULL, 1 );
                                        res = NULL;
 
                                        if ( rs->sr_err == LDAP_SUCCESS ) {
                                                rs->sr_err = err;
                                        }
+                                       rs->sr_err = slap_map_api2result( rs );
                                        
                                        /* FIXME: in case a referral 
                                         * is returned, should we try
@@ -385,15 +519,14 @@ retry:;
                                                ldap_install_tls( msc->msc_ld );
 
                                        } else if ( rs->sr_err == LDAP_REFERRAL ) {
+                                               /* FIXME: LDAP_OPERATIONS_ERROR? */
                                                rs->sr_err = LDAP_OTHER;
-                                               rs->sr_text = "unwilling to chase referral returned by Start TLS exop";
+                                               rs->sr_text = "Unwilling to chase referral "
+                                                       "returned by Start TLS exop";
                                        }
 
                                        if ( data ) {
-                                               if ( data->bv_val ) {
-                                                       ber_memfree( data->bv_val );
-                                               }
-                                               ber_memfree( data );
+                                               ber_bvfree( data );
                                        }
                                }
 
@@ -417,10 +550,20 @@ retry:;
                 * of misconfiguration, but also when used in the chain 
                 * overlay, where the "uri" can be parsed out of a referral */
                if ( rs->sr_err == LDAP_SERVER_DOWN
-                               || ( rs->sr_err != LDAP_SUCCESS && LDAP_BACK_TLS_CRITICAL( mi ) ) )
+                       || ( rs->sr_err != LDAP_SUCCESS
+                               && META_BACK_TGT_TLS_CRITICAL( mt ) ) )
                {
-                       ldap_unbind_ext( msc->msc_ld, NULL, NULL );
-                       msc->msc_ld = NULL;
+
+#ifdef DEBUG_205
+                       Debug( LDAP_DEBUG_ANY,
+                               "### %s meta_back_init_one_conn(TLS) "
+                               "ldap_unbind_ext[%d] ld=%p\n",
+                               op->o_log_prefix, candidate,
+                               (void *)msc->msc_ld );
+#endif /* DEBUG_205 */
+
+                       /* need to trash a failed Start TLS */
+                       meta_clear_one_candidate( op, mc, candidate );
                        goto error_return;
                }
        }
@@ -447,15 +590,18 @@ retry:;
                if ( !BER_BVISNULL( &mt->mt_idassert_authcDN ) ) {
                        ber_bvreplace( &msc->msc_bound_ndn, &mt->mt_idassert_authcDN );
                        if ( !BER_BVISNULL( &mt->mt_idassert_passwd ) ) {
+                               if ( !BER_BVISNULL( &msc->msc_cred ) ) {
+                                       memset( msc->msc_cred.bv_val, 0,
+                                               msc->msc_cred.bv_len );
+                               }
                                ber_bvreplace( &msc->msc_cred, &mt->mt_idassert_passwd );
                        }
+                       LDAP_BACK_CONN_ISIDASSERT_SET( msc );
 
                } else {
                        ber_bvreplace( &msc->msc_bound_ndn, &slap_empty_bv );
                }
 
-               LDAP_BACK_CONN_ISPRIV_SET( msc );
-
        } else {
                if ( !BER_BVISNULL( &msc->msc_cred ) ) {
                        memset( msc->msc_cred.bv_val, 0, msc->msc_cred.bv_len );
@@ -481,8 +627,17 @@ retry:;
                        if ( ldap_back_dn_massage( &dc, &op->o_conn->c_dn,
                                                &msc->msc_bound_ndn ) )
                        {
-                               ldap_unbind_ext( msc->msc_ld, NULL, NULL );
-                               msc->msc_ld = NULL;
+
+#ifdef DEBUG_205
+                               Debug( LDAP_DEBUG_ANY,
+                                       "### %s meta_back_init_one_conn(rewrite) "
+                                       "ldap_unbind_ext[%d] ld=%p\n",
+                                       op->o_log_prefix, candidate,
+                                       (void *)msc->msc_ld );
+#endif /* DEBUG_205 */
+
+                               /* need to trash a connection not fully established */
+                               meta_clear_one_candidate( op, mc, candidate );
                                goto error_return;
                        }
                        
@@ -491,6 +646,8 @@ retry:;
                                ber_dupbv( &msc->msc_bound_ndn, &op->o_conn->c_dn );
                        }
 
+                       assert( !BER_BVISNULL( &msc->msc_bound_ndn ) );
+
                } else {
                        ber_dupbv( &msc->msc_bound_ndn, (struct berval *)&slap_empty_bv );
                }
@@ -499,17 +656,25 @@ retry:;
        assert( !BER_BVISNULL( &msc->msc_bound_ndn ) );
 
 error_return:;
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_lock( &mi->mi_conninfo.lai_mutex );
+       }
+       META_BACK_CONN_CREATING_CLEAR( msc );
        if ( rs->sr_err == LDAP_SUCCESS ) {
                /*
                 * Sets a cookie for the rewrite session
                 */
                ( void )rewrite_session_init( mt->mt_rwmap.rwm_rw, op->o_conn );
+               META_BACK_CONN_INITED_SET( msc );
+       }
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
+       }
 
-       } else {
+       if ( rs->sr_err != LDAP_SUCCESS ) {
                rs->sr_err = slap_map_api2result( rs );
                if ( sendok & LDAP_BACK_SENDERR ) {
                        send_ldap_result( op, rs );
-                       rs->sr_text = NULL;
                }
        }
 
@@ -534,15 +699,24 @@ meta_back_retry(
        metaconn_t              *mc = *mcp;
        metasingleconn_t        *msc = &mc->mc_conns[ candidate ];
        int                     rc = LDAP_UNAVAILABLE,
-                               binding = LDAP_BACK_CONN_BINDING( msc );
+                               binding,
+                               quarantine = 1;
 
        ldap_pvt_thread_mutex_lock( &mi->mi_conninfo.lai_mutex );
 
+       assert( !META_BACK_CONN_CREATING( msc ) );
+       binding = LDAP_BACK_CONN_BINDING( msc );
+       LDAP_BACK_CONN_BINDING_CLEAR( msc );
+
        assert( mc->mc_refcnt > 0 );
        if ( mc->mc_refcnt == 1 ) {
+               struct berval save_cred;
+
                if ( LogTest( LDAP_DEBUG_ANY ) ) {
                        char    buf[ SLAP_TEXT_BUFLEN ];
 
+                       /* this lock is required; however,
+                        * it's invoked only when logging is on */
                        ldap_pvt_thread_mutex_lock( &mt->mt_uri_mutex );
                        snprintf( buf, sizeof( buf ),
                                "retrying URI=\"%s\" DN=\"%s\"",
@@ -556,19 +730,41 @@ meta_back_retry(
                                op->o_log_prefix, candidate, buf );
                }
 
-               meta_clear_one_candidate( msc );
+               /* save credentials, if any, for later use;
+                * meta_clear_one_candidate() would free them */
+               save_cred = msc->msc_cred;
+               BER_BVZERO( &msc->msc_cred );
+
+               meta_clear_one_candidate( op, mc, candidate );
                LDAP_BACK_CONN_ISBOUND_CLEAR( msc );
 
                ( void )rewrite_session_delete( mt->mt_rwmap.rwm_rw, op->o_conn );
 
                /* mc here must be the regular mc, reset and ready for init */
                rc = meta_back_init_one_conn( op, rs, mc, candidate,
-                       LDAP_BACK_CONN_ISPRIV( mc ), sendok );
+                       LDAP_BACK_CONN_ISPRIV( mc ), sendok, 0 );
+
+               /* restore credentials, if any and if needed;
+                * meta_back_init_one_conn() restores msc_bound_ndn, if any;
+                * if no msc_bound_ndn is restored, destroy credentials */
+               if ( !BER_BVISNULL( &msc->msc_bound_ndn )
+                       && BER_BVISNULL( &msc->msc_cred ) )
+               {
+                       msc->msc_cred = save_cred;
+
+               } else if ( !BER_BVISNULL( &save_cred ) ) {
+                       memset( save_cred.bv_val, 0, save_cred.bv_len );
+                       ber_memfree_x( save_cred.bv_val, NULL );
+               }
+
+               /* restore the "binding" flag, in case */
                if ( binding ) {
                        LDAP_BACK_CONN_BINDING_SET( msc );
                }
 
                if ( rc == LDAP_SUCCESS ) {
+                       quarantine = 0;
+                       LDAP_BACK_CONN_BINDING_SET( msc ); binding = 1;
                        rc = meta_back_single_dobind( op, rs, mcp, candidate,
                                sendok, mt->mt_nretries, 0 );
 
@@ -577,13 +773,24 @@ meta_back_retry(
                                "meta_back_single_dobind=%d\n",
                                op->o_log_prefix, candidate, rc );
                        if ( rc == LDAP_SUCCESS ) {
-                               if ( be_isroot( op )  ) {
+                               if ( !BER_BVISNULL( &msc->msc_bound_ndn ) &&
+                                       !BER_BVISEMPTY( &msc->msc_bound_ndn ) )
+                               {
                                        LDAP_BACK_CONN_ISBOUND_SET( msc );
+
                                } else {
                                        LDAP_BACK_CONN_ISANON_SET( msc );
                                }
+
+                               /* when bound, dispose of the "binding" flag */
+                               if ( binding ) {
+                                       LDAP_BACK_CONN_BINDING_CLEAR( msc );
+                               }
                        }
                }
+
+               /* don't send twice */
+               sendok &= ~LDAP_BACK_SENDERR;
        }
 
        if ( rc != LDAP_SUCCESS ) {
@@ -592,27 +799,61 @@ meta_back_retry(
                candidates[ candidate ].sr_err = rc;
 
                if ( *mcp != NULL ) {
-                       if ( binding ) {
-                               LDAP_BACK_CONN_BINDING_CLEAR( msc );
+                       if ( mc->mc_refcnt == 1 ) {
+                               if ( binding ) {
+                                       LDAP_BACK_CONN_BINDING_CLEAR( msc );
+                               }
+                               (void)meta_clear_one_candidate( op, mc, candidate );
                        }
+
                        LDAP_BACK_CONN_TAINTED_SET( mc );
                        /* only release if mandatory; otherwise
                         * let the caller do what's best before
                         * releasing */
                        if ( META_BACK_ONERR_STOP( mi ) ) {
-                               meta_back_release_conn_lock( op, mc, 0 );
+                               meta_back_release_conn_lock( mi, mc, 0 );
                                *mcp = NULL;
+
+                       } else {
+#if META_BACK_PRINT_CONNTREE > 0
+                               meta_back_print_conntree( mi, ">>> meta_back_retry" );
+#endif /* META_BACK_PRINT_CONNTREE */
+
+                               /* FIXME: could be done better, reworking meta_back_release_conn_lock() */
+                               if ( LDAP_BACK_PCONN_ISPRIV( mc ) ) {
+                                       if ( mc->mc_q.tqe_prev != NULL ) {
+                                               assert( LDAP_BACK_CONN_CACHED( mc ) );
+                                               assert( mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num > 0 );
+                                               LDAP_TAILQ_REMOVE( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv,
+                                                       mc, mc_q );
+                                               mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num--;
+                                               LDAP_TAILQ_ENTRY_INIT( mc, mc_q );
+
+                                       } else {
+                                               assert( !LDAP_BACK_CONN_CACHED( mc ) );
+                                       }
+
+                               } else {
+                                       /* FIXME: check if in tree, for consistency? */
+                                       (void)avl_delete( &mi->mi_conninfo.lai_tree,
+                                               ( caddr_t )mc, meta_back_conndnmc_cmp );
+                               }
+                               LDAP_BACK_CONN_CACHED_CLEAR( mc );
+
+#if META_BACK_PRINT_CONNTREE > 0
+                               meta_back_print_conntree( mi, "<<< meta_back_retry" );
+#endif /* META_BACK_PRINT_CONNTREE */
                        }
                }
 
-               if ( sendok ) {
+               if ( sendok & LDAP_BACK_SENDERR ) {
                        rs->sr_err = rc;
-                       rs->sr_text = NULL;
+                       rs->sr_text = "Unable to retry";
                        send_ldap_result( op, rs );
                }
        }
 
-       if ( META_BACK_TGT_QUARANTINE( mt ) ) {
+       if ( quarantine && META_BACK_TGT_QUARANTINE( mt ) ) {
                meta_back_quarantine( op, rs, candidate );
        }
 
@@ -666,12 +907,11 @@ meta_back_get_candidate(
         */
        if ( candidate == META_TARGET_NONE ) {
                rs->sr_err = LDAP_NO_SUCH_OBJECT;
-               rs->sr_text = "no suitable candidate target found";
+               rs->sr_text = "No suitable candidate target found";
 
        } else if ( candidate == META_TARGET_MULTIPLE ) {
-               Filter          f = { 0 };
                Operation       op2 = *op;
-               SlapReply       rs2 = { 0 };
+               SlapReply       rs2 = { REP_RESULT };
                slap_callback   cb2 = { 0 };
                int             rc;
 
@@ -688,10 +928,8 @@ meta_back_get_candidate(
                op2.ors_slimit = 1;
                op2.ors_tlimit = SLAP_NO_LIMIT;
 
-               f.f_choice = LDAP_FILTER_PRESENT;
-               f.f_desc = slap_schema.si_ad_objectClass;
-               op2.ors_filter = &f;
-               BER_BVSTR( &op2.ors_filterstr, "(objectClass=*)" );
+               op2.ors_filter = (Filter *)slap_filter_objectClass_pres;
+               op2.ors_filterstr = *slap_filterstr_objectClass_pres;
 
                op2.o_callback = &cb2;
                cb2.sc_response = meta_back_conn_cb;
@@ -719,7 +957,7 @@ meta_back_get_candidate(
 
                        } else {
                                rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
-                               rs->sr_text = "cannot select unique candidate target";
+                               rs->sr_text = "Unable to select unique candidate target";
                        }
                        break;
                }
@@ -771,7 +1009,8 @@ meta_back_candidates_get( Operation *op )
                        data = (void *)mc;
                        ldap_pvt_thread_pool_setkey( op->o_threadctx,
                                        &meta_back_candidates_dummy, data,
-                                       meta_back_candidates_keyfree );
+                                       meta_back_candidates_keyfree,
+                                       NULL, NULL );
 
                } else {
                        mi->mi_candidates = mc;
@@ -832,7 +1071,7 @@ meta_back_getconn(
 {
        metainfo_t      *mi = ( metainfo_t * )op->o_bd->be_private;
        metaconn_t      *mc = NULL,
-                       mc_curr = { 0 };
+                       mc_curr = {{ 0 }};
        int             cached = META_TARGET_NONE,
                        i = META_TARGET_NONE,
                        err = LDAP_SUCCESS,
@@ -845,59 +1084,150 @@ meta_back_getconn(
                META_DNTYPE_ENTRY,
                META_DNTYPE_PARENT,
                META_DNTYPE_NEWPARENT
-                       } dn_type = META_DNTYPE_ENTRY;
+       }               dn_type = META_DNTYPE_ENTRY;
        struct berval   ndn = op->o_req_ndn,
                        pndn;
 
        SlapReply       *candidates = meta_back_candidates_get( op );
 
        /* Internal searches are privileged and shared. So is root. */
-       /* FIXME: there seem to be concurrency issues */
-       if ( op->o_do_not_cache || be_isroot( op ) ) {
-               mc_curr.mc_local_ndn = op->o_bd->be_rootndn;
+       if ( ( !BER_BVISEMPTY( &op->o_ndn ) && META_BACK_PROXYAUTHZ_ALWAYS( mi ) )
+               || ( BER_BVISEMPTY( &op->o_ndn ) && META_BACK_PROXYAUTHZ_ANON( mi ) )
+               || op->o_do_not_cache || be_isroot( op ) )
+       {
                LDAP_BACK_CONN_ISPRIV_SET( &mc_curr );
-               mc_curr.mc_conn = LDAP_BACK_PCONN_SET( op );
+               mc_curr.mc_local_ndn = op->o_bd->be_rootndn;
+               LDAP_BACK_PCONN_ROOTDN_SET( &mc_curr, op );
+
+       } else if ( BER_BVISEMPTY( &op->o_ndn ) && META_BACK_PROXYAUTHZ_NOANON( mi ) )
+       {
+               LDAP_BACK_CONN_ISANON_SET( &mc_curr );
+               BER_BVSTR( &mc_curr.mc_local_ndn, "" );
+               LDAP_BACK_PCONN_ANON_SET( &mc_curr, op );
 
        } else {
                mc_curr.mc_local_ndn = op->o_ndn;
 
                /* Explicit binds must not be shared */
-               if ( op->o_tag == LDAP_REQ_BIND || SLAP_IS_AUTHZ_BACKEND( op ) ) {
+               if ( !BER_BVISEMPTY( &op->o_ndn )
+                       || op->o_tag == LDAP_REQ_BIND
+                       || SLAP_IS_AUTHZ_BACKEND( op ) )
+               {
                        mc_curr.mc_conn = op->o_conn;
        
                } else {
-                       mc_curr.mc_conn = LDAP_BACK_PCONN_SET( op );
+                       LDAP_BACK_CONN_ISANON_SET( &mc_curr );
+                       LDAP_BACK_PCONN_ANON_SET( &mc_curr, op );
                }
        }
 
        /* Explicit Bind requests always get their own conn */
-       if ( !( sendok & LDAP_BACK_BINDING ) ) {
+       if ( sendok & LDAP_BACK_BINDING ) {
+               mc_curr.mc_conn = op->o_conn;
+
+       } else {
                /* Searches for a metaconn in the avl tree */
 retry_lock:;
                ldap_pvt_thread_mutex_lock( &mi->mi_conninfo.lai_mutex );
-               mc = (metaconn_t *)avl_find( mi->mi_conninfo.lai_tree, 
-                       (caddr_t)&mc_curr, meta_back_conndn_cmp );
-               if ( mc ) {
-                       if ( ( mi->mi_conn_ttl != 0 && op->o_time > mc->mc_create_time + mi->mi_conn_ttl )
-                               || ( mi->mi_idle_timeout != 0 && op->o_time > mc->mc_time + mi->mi_idle_timeout ) )
+               if ( LDAP_BACK_PCONN_ISPRIV( &mc_curr ) ) {
+                       /* lookup a conn that's not binding */
+                       LDAP_TAILQ_FOREACH( mc,
+                               &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( &mc_curr ) ].mic_priv,
+                               mc_q )
                        {
-                               /* don't let anyone else use this expired connection */
-                               (void)avl_delete( &mi->mi_conninfo.lai_tree,
-                                       (caddr_t)mc, meta_back_conndnmc_cmp );
-                               LDAP_BACK_CONN_TAINTED_SET( mc );
+                               if ( !LDAP_BACK_CONN_BINDING( mc ) && mc->mc_refcnt == 0 ) {
+                                       break;
+                               }
+                       }
+
+                       if ( mc != NULL ) {
+                               /* move to tail of queue */
+                               if ( mc != LDAP_TAILQ_LAST( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv,
+                                       metaconn_t, mc_q ) )
+                               {
+                                       LDAP_TAILQ_REMOVE( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv,
+                                               mc, mc_q );
+                                       LDAP_TAILQ_ENTRY_INIT( mc, mc_q );
+                                       LDAP_TAILQ_INSERT_TAIL( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv,
+                                               mc, mc_q );
+                               }
 
-                               Debug( LDAP_DEBUG_TRACE, "%s meta_back_getconn: mc=%p conn=%ld expired.\n",
-                                       op->o_log_prefix, (void *)mc, LDAP_BACK_PCONN_ID( mc->mc_conn ) );
+                       } else if ( !LDAP_BACK_USE_TEMPORARIES( mi )
+                               && mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( &mc_curr ) ].mic_num == mi->mi_conn_priv_max )
+                       {
+                               mc = LDAP_TAILQ_FIRST( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( &mc_curr ) ].mic_priv );
                        }
+                       
+
+               } else {
+                       mc = (metaconn_t *)avl_find( mi->mi_conninfo.lai_tree, 
+                               (caddr_t)&mc_curr, meta_back_conndn_cmp );
+               }
+
+               if ( mc ) {
+                       /* catch taint errors */
+                       assert( !LDAP_BACK_CONN_TAINTED( mc ) );
 
-                       /* Don't reuse connections while they're still binding */
+                       /* Don't reuse connections while they're still binding
+                        * NOTE: only makes sense for binds */
                        if ( LDAP_BACK_CONN_BINDING( mc ) ) {
-                               ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
-                               ldap_pvt_thread_yield();
-                               goto retry_lock;
-                       }
+                               if ( !LDAP_BACK_USE_TEMPORARIES( mi ) ) {
+                                       ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
+
+                                       ldap_pvt_thread_yield();
+                                       goto retry_lock;
+                               }
+
+                               /* release conn, and create a temporary */
+                               mc = NULL;
+
+                       } else {
+                               if ( mc->mc_refcnt == 0 && (( mi->mi_conn_ttl != 0 && op->o_time > mc->mc_create_time + mi->mi_conn_ttl )
+                                       || ( mi->mi_idle_timeout != 0 && op->o_time > mc->mc_time + mi->mi_idle_timeout )) )
+                               {
+#if META_BACK_PRINT_CONNTREE > 0
+                                       meta_back_print_conntree( mi,
+                                               ">>> meta_back_getconn(expired)" );
+#endif /* META_BACK_PRINT_CONNTREE */
+
+                                       /* don't let anyone else use this expired connection */
+                                       if ( LDAP_BACK_PCONN_ISPRIV( mc ) ) {
+                                               if ( mc->mc_q.tqe_prev != NULL ) {
+                                                       assert( LDAP_BACK_CONN_CACHED( mc ) );
+                                                       assert( mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num > 0 );
+                                                       LDAP_TAILQ_REMOVE( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv,
+                                                               mc, mc_q );
+                                                       mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num--;
+                                                       LDAP_TAILQ_ENTRY_INIT( mc, mc_q );
+
+                                               } else {
+                                                       assert( !LDAP_BACK_CONN_CACHED( mc ) );
+                                               }
+
+                                       } else {
+                                               (void)avl_delete( &mi->mi_conninfo.lai_tree,
+                                                       (caddr_t)mc, meta_back_conndnmc_cmp );
+                                       }
+
+#if META_BACK_PRINT_CONNTREE > 0
+                                       meta_back_print_conntree( mi,
+                                               "<<< meta_back_getconn(expired)" );
+#endif /* META_BACK_PRINT_CONNTREE */
+                                       LDAP_BACK_CONN_TAINTED_SET( mc );
+                                       LDAP_BACK_CONN_CACHED_CLEAR( mc );
+
+                                       if ( LogTest( LDAP_DEBUG_TRACE ) ) {
+                                               char buf[STRLENOF("4294967295U") + 1] = { 0 };
+                                               mi->mi_ldap_extra->connid2str( &mc->mc_base, buf, sizeof(buf) );
+
+                                               Debug( LDAP_DEBUG_TRACE,
+                                                       "%s meta_back_getconn: mc=%p conn=%s expired (tainted).\n",
+                                                       op->o_log_prefix, (void *)mc, buf );
+                                       }
+                               }
 
-                       mc->mc_refcnt++;
+                               mc->mc_refcnt++;
+                       }
                }
                ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
        }
@@ -920,18 +1250,19 @@ retry_lock:;
 
        case LDAP_REQ_BIND:
                /* if bound as rootdn, the backend must bind to all targets
-                * with the administrative identity */
+                * with the administrative identity
+                * (unless pseoudoroot-bind-defer is TRUE) */
                if ( op->orb_method == LDAP_AUTH_SIMPLE && be_isroot_pw( op ) ) {
                        op_type = META_OP_REQUIRE_ALL;
                }
                break;
 
+       case LDAP_REQ_COMPARE:
        case LDAP_REQ_DELETE:
        case LDAP_REQ_MODIFY:
                /* just a unique candidate */
                break;
 
-       case LDAP_REQ_COMPARE:
        case LDAP_REQ_SEARCH:
                /* allow multiple candidates for the searchBase */
                op_type = META_OP_ALLOW_MULTIPLE;
@@ -957,6 +1288,16 @@ retry_lock:;
                        if ( sendok & LDAP_BACK_BINDING ) {
                                LDAP_BACK_CONN_BINDING_SET( mc );
                        }
+                       if ( LDAP_BACK_CONN_ISPRIV( &mc_curr ) ) {
+                               LDAP_BACK_CONN_ISPRIV_SET( mc );
+
+                       } else if ( LDAP_BACK_CONN_ISANON( &mc_curr ) ) {
+                               LDAP_BACK_CONN_ISANON_SET( mc );
+                       }
+
+               } else if ( 0 ) {
+                       /* TODO: if any of the connections is binding,
+                        * release mc and create a new one */
                }
 
                for ( i = 0; i < mi->mi_ntargets; i++ ) {
@@ -966,8 +1307,11 @@ retry_lock:;
                         */
                        candidates[ i ].sr_err = meta_back_init_one_conn( op,
                                rs, mc, i, LDAP_BACK_CONN_ISPRIV( &mc_curr ),
-                               sendok );
+                               LDAP_BACK_DONTSEND, !new_conn );
                        if ( candidates[ i ].sr_err == LDAP_SUCCESS ) {
+                               if ( new_conn && ( sendok & LDAP_BACK_BINDING ) ) {
+                                       LDAP_BACK_CONN_BINDING_SET( &mc->mc_conns[ i ] );
+                               }
                                META_CANDIDATE_SET( &candidates[ i ] );
                                ncandidates++;
        
@@ -990,7 +1334,7 @@ retry_lock:;
                                meta_back_conn_free( mc );
 
                        } else {
-                               meta_back_release_conn( op, mc );
+                               meta_back_release_conn( mi, mc );
                        }
 
                        rs->sr_err = LDAP_NO_SUCH_OBJECT;
@@ -1001,7 +1345,6 @@ retry_lock:;
                                        rs->sr_matched = op->o_bd->be_suffix[ 0 ].bv_val;
                                }
                                send_ldap_result( op, rs );
-                               rs->sr_text = NULL;
                                rs->sr_matched = NULL;
                        }
 
@@ -1041,7 +1384,7 @@ retry_lock:;
        
                        if ( i < 0 || rs->sr_err != LDAP_SUCCESS ) {
                                if ( mc != NULL ) {
-                                       meta_back_release_conn( op, mc );
+                                       meta_back_release_conn( mi, mc );
                                }
 
                                if ( sendok & LDAP_BACK_SENDERR ) {
@@ -1049,7 +1392,6 @@ retry_lock:;
                                                rs->sr_matched = op->o_bd->be_suffix[ 0 ].bv_val;
                                        }
                                        send_ldap_result( op, rs );
-                                       rs->sr_text = NULL;
                                        rs->sr_matched = NULL;
                                }
                        
@@ -1060,14 +1402,13 @@ retry_lock:;
                if ( dn_type == META_DNTYPE_NEWPARENT && meta_back_get_candidate( op, rs, op->orr_nnewSup ) != i )
                {
                        if ( mc != NULL ) {
-                               meta_back_release_conn( op, mc );
+                               meta_back_release_conn( mi, mc );
                        }
 
                        rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
-                       rs->sr_text = "cross-target rename not supported";
+                       rs->sr_text = "Cross-target rename not supported";
                        if ( sendok & LDAP_BACK_SENDERR ) {
                                send_ldap_result( op, rs );
-                               rs->sr_text = NULL;
                        }
 
                        return NULL;
@@ -1087,14 +1428,24 @@ retry_lock2:;
                                mc = (metaconn_t *)avl_find( mi->mi_conninfo.lai_tree, 
                                        (caddr_t)&mc_curr, meta_back_conndn_cmp );
                                if ( mc != NULL ) {
+                                       /* catch taint errors */
+                                       assert( !LDAP_BACK_CONN_TAINTED( mc ) );
+
                                        /* Don't reuse connections while they're still binding */
-                                       if ( LDAP_BACK_CONN_BINDING( mc ) ) {
-                                               ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
-                                               ldap_pvt_thread_yield();
-                                               goto retry_lock2;
-                                       }
+                                       if ( META_BACK_CONN_CREATING( &mc->mc_conns[ i ] )
+                                               || LDAP_BACK_CONN_BINDING( &mc->mc_conns[ i ] ) )
+                                       {
+                                               if ( !LDAP_BACK_USE_TEMPORARIES( mi ) ) {
+                                                       ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
+                                                       ldap_pvt_thread_yield();
+                                                       goto retry_lock2;
+                                               }
 
-                                       mc->mc_refcnt++;
+                                               mc = NULL;
+
+                                       } else {
+                                               mc->mc_refcnt++;
+                                       }
                                }
                                ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
                        }
@@ -1109,6 +1460,12 @@ retry_lock2:;
                                if ( sendok & LDAP_BACK_BINDING ) {
                                        LDAP_BACK_CONN_BINDING_SET( mc );
                                }
+                               if ( LDAP_BACK_CONN_ISPRIV( &mc_curr ) ) {
+                                       LDAP_BACK_CONN_ISPRIV_SET( mc );
+
+                               } else if ( LDAP_BACK_CONN_ISANON( &mc_curr ) ) {
+                                       LDAP_BACK_CONN_ISANON_SET( mc );
+                               }
                        }
                }
 
@@ -1126,7 +1483,7 @@ retry_lock2:;
                 * sends the appropriate result.
                 */
                err = meta_back_init_one_conn( op, rs, mc, i,
-                       LDAP_BACK_CONN_ISPRIV( &mc_curr ), sendok );
+                       LDAP_BACK_CONN_ISPRIV( &mc_curr ), sendok, !new_conn );
                if ( err != LDAP_SUCCESS ) {
                        /*
                         * FIXME: in case one target cannot
@@ -1139,11 +1496,15 @@ retry_lock2:;
                                meta_back_conn_free( mc );
 
                        } else {
-                               meta_back_release_conn( op, mc );
+                               meta_back_release_conn( mi, mc );
                        }
                        return NULL;
                }
 
+               if ( new_conn && ( sendok & LDAP_BACK_BINDING ) ) {
+                       LDAP_BACK_CONN_BINDING_SET( &mc->mc_conns[ i ] );
+               }
+
                candidates[ i ].sr_err = LDAP_SUCCESS;
                META_CANDIDATE_SET( &candidates[ i ] );
                ncandidates++;
@@ -1164,18 +1525,22 @@ retry_lock2:;
                        mc->mc_conn = mc_curr.mc_conn;
                        ber_dupbv( &mc->mc_local_ndn, &mc_curr.mc_local_ndn );
                        new_conn = 1;
-                       if ( sendok & LDAP_BACK_BINDING ) {
-                               LDAP_BACK_CONN_BINDING_SET( mc );
+                       if ( LDAP_BACK_CONN_ISPRIV( &mc_curr ) ) {
+                               LDAP_BACK_CONN_ISPRIV_SET( mc );
+
+                       } else if ( LDAP_BACK_CONN_ISANON( &mc_curr ) ) {
+                               LDAP_BACK_CONN_ISANON_SET( mc );
                        }
                }
 
                for ( i = 0; i < mi->mi_ntargets; i++ ) {
                        metatarget_t            *mt = mi->mi_targets[ i ];
-                       metasingleconn_t        *msc = &mc->mc_conns[ i ];
+
+                       META_CANDIDATE_RESET( &candidates[ i ] );
 
                        if ( i == cached 
                                || meta_back_is_candidate( mt, &op->o_req_ndn,
-                                       LDAP_SCOPE_SUBTREE ) )
+                                       op->o_tag == LDAP_REQ_SEARCH ? op->ors_scope : LDAP_SCOPE_SUBTREE ) )
                        {
 
                                /*
@@ -1183,10 +1548,11 @@ retry_lock2:;
                                 * also init'd
                                 */
                                int lerr = meta_back_init_one_conn( op, rs, mc, i,
-                                       LDAP_BACK_CONN_ISPRIV( &mc_curr ), LDAP_BACK_DONTSEND );
+                                       LDAP_BACK_CONN_ISPRIV( &mc_curr ),
+                                       LDAP_BACK_DONTSEND, !new_conn );
+                               candidates[ i ].sr_err = lerr;
                                if ( lerr == LDAP_SUCCESS ) {
                                        META_CANDIDATE_SET( &candidates[ i ] );
-                                       candidates[ i ].sr_err = LDAP_SUCCESS;
                                        ncandidates++;
 
                                        Debug( LDAP_DEBUG_TRACE, "%s: meta_back_getconn[%d]\n",
@@ -1194,7 +1560,6 @@ retry_lock2:;
 
                                } else if ( lerr == LDAP_UNAVAILABLE && !META_BACK_ONERR_STOP( mi ) ) {
                                        META_CANDIDATE_SET( &candidates[ i ] );
-                                       candidates[ i ].sr_err = LDAP_UNAVAILABLE;
 
                                        Debug( LDAP_DEBUG_TRACE, "%s: meta_back_getconn[%d] %s\n",
                                                op->o_log_prefix, i,
@@ -1208,46 +1573,42 @@ retry_lock2:;
                                         * be tried?
                                         */
                                        if ( new_conn ) {
-                                               ( void )meta_clear_one_candidate( msc );
+                                               ( void )meta_clear_one_candidate( op, mc, i );
                                        }
                                        /* leave the target candidate, but record the error for later use */
-                                       candidates[ i ].sr_err = lerr;
                                        err = lerr;
 
                                        if ( lerr == LDAP_UNAVAILABLE && mt->mt_isquarantined != LDAP_BACK_FQ_NO ) {
-                                               Debug( LDAP_DEBUG_TRACE, "%s: meta_back_getconn[%d] quarantined%d\n",
+                                               Debug( LDAP_DEBUG_TRACE, "%s: meta_back_getconn[%d] quarantined err=%d\n",
                                                        op->o_log_prefix, i, lerr );
 
                                        } else {
-                                               Debug( LDAP_DEBUG_ANY, "%s: meta_back_getconn[%d] failed%d\n",
+                                               Debug( LDAP_DEBUG_ANY, "%s: meta_back_getconn[%d] failed err=%d\n",
                                                        op->o_log_prefix, i, lerr );
                                        }
 
                                        if ( META_BACK_ONERR_STOP( mi ) ) {
                                                if ( sendok & LDAP_BACK_SENDERR ) {
                                                        send_ldap_result( op, rs );
-                                                       rs->sr_text = NULL;
                                                }
                                                if ( new_conn ) {
                                                        mc->mc_refcnt = 0;
                                                        meta_back_conn_free( mc );
 
                                                } else {
-                                                       meta_back_release_conn( op, mc );
+                                                       meta_back_release_conn( mi, mc );
                                                }
 
                                                return NULL;
                                        }
 
-                                       rs->sr_text = NULL;
                                        continue;
                                }
 
                        } else {
                                if ( new_conn ) {
-                                       ( void )meta_clear_one_candidate( msc );
+                                       ( void )meta_clear_one_candidate( op, mc, i );
                                }
-                               META_CANDIDATE_RESET( &candidates[ i ] );
                        }
                }
 
@@ -1257,18 +1618,19 @@ retry_lock2:;
                                meta_back_conn_free( mc );
 
                        } else {
-                               meta_back_release_conn( op, mc );
+                               meta_back_release_conn( mi, mc );
                        }
 
-                       rs->sr_err = LDAP_NO_SUCH_OBJECT;
-                       rs->sr_text = "Unable to select valid candidates";
+                       if ( rs->sr_err == LDAP_SUCCESS ) {
+                               rs->sr_err = LDAP_NO_SUCH_OBJECT;
+                               rs->sr_text = "Unable to select valid candidates";
+                       }
 
                        if ( sendok & LDAP_BACK_SENDERR ) {
                                if ( rs->sr_err == LDAP_NO_SUCH_OBJECT ) {
                                        rs->sr_matched = op->o_bd->be_suffix[ 0 ].bv_val;
                                }
                                send_ldap_result( op, rs );
-                               rs->sr_text = NULL;
                                rs->sr_matched = NULL;
                        }
 
@@ -1295,72 +1657,107 @@ done:;
                 * Inserts the newly created metaconn in the avl tree
                 */
                ldap_pvt_thread_mutex_lock( &mi->mi_conninfo.lai_mutex );
-               err = avl_insert( &mi->mi_conninfo.lai_tree, ( caddr_t )mc,
+#if META_BACK_PRINT_CONNTREE > 0
+               meta_back_print_conntree( mi, ">>> meta_back_getconn" );
+#endif /* META_BACK_PRINT_CONNTREE */
+
+               err = 0;
+               if ( LDAP_BACK_PCONN_ISPRIV( mc ) ) {
+                       if ( mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num < mi->mi_conn_priv_max ) {
+                               LDAP_TAILQ_INSERT_TAIL( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv, mc, mc_q );
+                               mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num++;
+                               LDAP_BACK_CONN_CACHED_SET( mc );
+
+                       } else {
+                               LDAP_BACK_CONN_TAINTED_SET( mc );
+                       }
+                       rs->sr_err = 0;
+
+               } else if ( !( sendok & LDAP_BACK_BINDING ) ) {
+                       err = avl_insert( &mi->mi_conninfo.lai_tree, ( caddr_t )mc,
                                meta_back_conndn_cmp, meta_back_conndn_dup );
+                       LDAP_BACK_CONN_CACHED_SET( mc );
+               }
 
-#if PRINT_CONNTREE > 0
-               myprint( mi->mi_conninfo.lai_tree, "meta_back_getconn" );
-#endif /* PRINT_CONNTREE */
-               
+#if META_BACK_PRINT_CONNTREE > 0
+               meta_back_print_conntree( mi, "<<< meta_back_getconn" );
+#endif /* META_BACK_PRINT_CONNTREE */
                ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
 
-               /*
-                * Err could be -1 in case a duplicate metaconn is inserted
-                */
-               switch ( err ) {
-               case 0:
-                       break;
+               if ( !LDAP_BACK_PCONN_ISPRIV( mc ) ) {
+                       /*
+                        * Err could be -1 in case a duplicate metaconn is inserted
+                        */
+                       switch ( err ) {
+                       case 0:
+                               break;
+
+                       case -1:
+                               LDAP_BACK_CONN_CACHED_CLEAR( mc );
+                               /* duplicate: free and try to get the newly created one */
+                               if ( !( sendok & LDAP_BACK_BINDING ) && !LDAP_BACK_USE_TEMPORARIES( mi ) ) {
+                                       mc->mc_refcnt = 0;      
+                                       meta_back_conn_free( mc );
+       
+                                       new_conn = 0;
+                                       goto retry_lock;
+                               }
 
-               case -1:
-                       /* duplicate: free and try to get the newly created one */
-                       if ( !( sendok & LDAP_BACK_BINDING ) ) {
-                               new_conn = 0;
-                               goto retry_lock;
-                       }
-                       LDAP_BACK_CONN_TAINTED_SET( mc );
-                       break;
+                               LDAP_BACK_CONN_TAINTED_SET( mc );
+                               break;
 
-               default:
-                       Debug( LDAP_DEBUG_ANY,
-                               "%s meta_back_getconn: candidates=%d conn=%ld insert failed\n",
-                               op->o_log_prefix, ncandidates,
-                               LDAP_BACK_PCONN_ID( mc->mc_conn ) );
+                       default:
+                               LDAP_BACK_CONN_CACHED_CLEAR( mc );
+                               if ( LogTest( LDAP_DEBUG_ANY ) ) {
+                                       char buf[STRLENOF("4294967295U") + 1] = { 0 };
+                                       mi->mi_ldap_extra->connid2str( &mc->mc_base, buf, sizeof(buf) );
+
+                                       Debug( LDAP_DEBUG_ANY,
+                                               "%s meta_back_getconn: candidates=%d conn=%s insert failed\n",
+                                               op->o_log_prefix, ncandidates, buf );
+                               }
        
-                       mc->mc_refcnt = 0;      
-                       meta_back_conn_free( mc );
+                               mc->mc_refcnt = 0;      
+                               meta_back_conn_free( mc );
 
-                       rs->sr_err = LDAP_OTHER;
-                       rs->sr_text = "proxy bind collision";
-                       if ( sendok & LDAP_BACK_SENDERR ) {
-                               send_ldap_result( op, rs );
-                               rs->sr_text = NULL;
+                               rs->sr_err = LDAP_OTHER;
+                               rs->sr_text = "Proxy bind collision";
+                               if ( sendok & LDAP_BACK_SENDERR ) {
+                                       send_ldap_result( op, rs );
+                               }
+                               return NULL;
                        }
-                       return NULL;
                }
 
-               Debug( LDAP_DEBUG_TRACE,
-                       "%s meta_back_getconn: candidates=%d conn=%ld inserted\n",
-                       op->o_log_prefix, ncandidates,
-                       LDAP_BACK_PCONN_ID( mc->mc_conn ) );
+               if ( LogTest( LDAP_DEBUG_TRACE ) ) {
+                       char buf[STRLENOF("4294967295U") + 1] = { 0 };
+                       mi->mi_ldap_extra->connid2str( &mc->mc_base, buf, sizeof(buf) );
+
+                       Debug( LDAP_DEBUG_TRACE,
+                               "%s meta_back_getconn: candidates=%d conn=%s inserted\n",
+                               op->o_log_prefix, ncandidates, buf );
+               }
 
        } else {
-               Debug( LDAP_DEBUG_TRACE,
-                       "%s meta_back_getconn: candidates=%d conn=%ld fetched\n",
-                       op->o_log_prefix, ncandidates,
-                       LDAP_BACK_PCONN_ID( mc->mc_conn ) );
+               if ( LogTest( LDAP_DEBUG_TRACE ) ) {
+                       char buf[STRLENOF("4294967295U") + 1] = { 0 };
+                       mi->mi_ldap_extra->connid2str( &mc->mc_base, buf, sizeof(buf) );
+
+                       Debug( LDAP_DEBUG_TRACE,
+                               "%s meta_back_getconn: candidates=%d conn=%s fetched\n",
+                               op->o_log_prefix, ncandidates, buf );
+               }
        }
-       
+
        return mc;
 }
 
 void
 meta_back_release_conn_lock(
-               Operation               *op,
+               metainfo_t              *mi,
        metaconn_t              *mc,
        int                     dolock )
 {
-       metainfo_t      *mi = ( metainfo_t * )op->o_bd->be_private;
-
        assert( mc != NULL );
 
        if ( dolock ) {
@@ -1368,16 +1765,55 @@ meta_back_release_conn_lock(
        }
        assert( mc->mc_refcnt > 0 );
        mc->mc_refcnt--;
-       LDAP_BACK_CONN_BINDING_CLEAR( mc );
-       if ( LDAP_BACK_CONN_TAINTED( mc ) ) {
-               Debug( LDAP_DEBUG_TRACE, "%s meta_back_release_conn: mc=%p conn=%ld tainted.\n",
-                       op->o_log_prefix, (void *)mc, LDAP_BACK_PCONN_ID( mc->mc_conn ) );
-               (void)avl_delete( &mi->mi_conninfo.lai_tree,
-                       ( caddr_t )mc, meta_back_conndnmc_cmp );
+       /* NOTE: the connection is removed if either it is tainted
+        * or if it is shared and no one else is using it.  This needs
+        * to occur because for intrinsic reasons cached connections
+        * that are not privileged would live forever and pollute
+        * the connection space (and eat up resources).  Maybe this
+        * should be configurable... */
+       if ( LDAP_BACK_CONN_TAINTED( mc ) || !LDAP_BACK_CONN_CACHED( mc ) ) {
+#if META_BACK_PRINT_CONNTREE > 0
+               meta_back_print_conntree( mi, ">>> meta_back_release_conn" );
+#endif /* META_BACK_PRINT_CONNTREE */
+
+               if ( LDAP_BACK_PCONN_ISPRIV( mc ) ) {
+                       if ( mc->mc_q.tqe_prev != NULL ) {
+                               assert( LDAP_BACK_CONN_CACHED( mc ) );
+                               assert( mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num > 0 );
+                               LDAP_TAILQ_REMOVE( &mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_priv, mc, mc_q );
+                               mi->mi_conn_priv[ LDAP_BACK_CONN2PRIV( mc ) ].mic_num--;
+                               LDAP_TAILQ_ENTRY_INIT( mc, mc_q );
+
+                       } else {
+                               assert( !LDAP_BACK_CONN_CACHED( mc ) );
+                       }
+
+               } else if ( LDAP_BACK_CONN_CACHED( mc ) ) {
+                       metaconn_t      *tmpmc;
+
+                       tmpmc = avl_delete( &mi->mi_conninfo.lai_tree,
+                               ( caddr_t )mc, meta_back_conndnmc_cmp );
+
+                       /* Overparanoid, but useful... */
+                       assert( tmpmc == NULL || tmpmc == mc );
+               }
+
+               LDAP_BACK_CONN_CACHED_CLEAR( mc );
+
+#if META_BACK_PRINT_CONNTREE > 0
+               meta_back_print_conntree( mi, "<<< meta_back_release_conn" );
+#endif /* META_BACK_PRINT_CONNTREE */
+
                if ( mc->mc_refcnt == 0 ) {
                        meta_back_conn_free( mc );
+                       mc = NULL;
                }
        }
+
+       if ( mc != NULL && LDAP_BACK_CONN_BINDING( mc ) ) {
+               LDAP_BACK_CONN_BINDING_CLEAR( mc );
+       }
+
        if ( dolock ) {
                ldap_pvt_thread_mutex_unlock( &mi->mi_conninfo.lai_mutex );
        }
@@ -1458,4 +1894,3 @@ meta_back_quarantine(
 done:;
        ldap_pvt_thread_mutex_unlock( &mt->mt_quarantine_mutex );
 }
-