text: /* bind.c - ldap backend bind function */
  /* $OpenLDAP$ */
  /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   *
   * Copyright 1999-2012 The OpenLDAP Foundation.
   * Portions Copyright 2000-2003 Pierangelo Masarati.
   * Portions Copyright 1999-2003 Howard Chu.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted only as authorized by the OpenLDAP
   * Public License.
   *
   * A copy of this license is available in the file LICENSE in the
   * top-level directory of the distribution or, alternatively, at
   * <http://www.OpenLDAP.org/license.html>.
   */
  /* ACKNOWLEDGEMENTS:
   * This work was initially developed by Howard Chu for inclusion
   * in OpenLDAP Software and subsequently enhanced by Pierangelo
   * Masarati.
   */
  
  #include "portable.h"
  
  #include <stdio.h>
  
  #include <ac/errno.h>
  #include <ac/socket.h>
  #include <ac/string.h>
  
  #define AVL_INTERNAL
  #include "slap.h"
  #include "back-ldap.h"
  #include "lutil.h"
  #include "lutil_ldap.h"
  
  #define LDAP_CONTROL_OBSOLETE_PROXY_AUTHZ	"2.16.840.1.113730.3.4.12"
  
  #ifdef LDAP_DEVEL
  #define SLAP_AUTH_DN 1
  #endif
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  
  static const struct {
  	slap_mask_t	f;
  	char		c;
  } flagsmap[] = {
  	{ LDAP_BACK_FCONN_ISBOUND,	'B' },
  	{ LDAP_BACK_FCONN_ISANON,	'A' },
  	{ LDAP_BACK_FCONN_ISPRIV,	'P' },
  	{ LDAP_BACK_FCONN_ISTLS,	'T' },
  	{ LDAP_BACK_FCONN_BINDING,	'X' },
  	{ LDAP_BACK_FCONN_TAINTED,	'E' },
  	{ LDAP_BACK_FCONN_ABANDON,	'N' },
  	{ LDAP_BACK_FCONN_ISIDASR,	'S' },
  	{ LDAP_BACK_FCONN_CACHED,	'C' },
  	{ 0,				'\0' }
  };
  
  static void
  ldap_back_conn_print( ldapconn_t *lc, const char *avlstr )
  {
  	char buf[ SLAP_TEXT_BUFLEN ];
  	char fbuf[ sizeof("BAPTIENSC") ];
  	int i;
  
  	ldap_back_conn2str( &lc->lc_base, buf, sizeof( buf ) );
  	for ( i = 0; flagsmap[ i ].c != '\0'; i++ ) {
  		if ( lc->lc_lcflags & flagsmap[i].f ) {
  			fbuf[i] = flagsmap[i].c;
  
  		} else {
  			fbuf[i] = '.';
  		}
  	}
  	fbuf[i] = '\0';
  	
  	fprintf( stderr, "lc=%p %s %s flags=0x%08x (%s)\n",
  		(void *)lc, buf, avlstr, lc->lc_lcflags, fbuf );
  }
  
  static void
  ldap_back_ravl_print( Avlnode *root, int depth )
  {
  	int		i;
  	ldapconn_t	*lc;
  	
  	if ( root == 0 ) {
  		return;
  	}
  	
  	ldap_back_ravl_print( root->avl_right, depth+1 );
  	
  	for ( i = 0; i < depth; i++ ) {
  		fprintf( stderr, "-" );
  	}
  
  	lc = root->avl_data;
  	ldap_back_conn_print( lc, avl_bf2str( root->avl_bf ) );
  
  	ldap_back_ravl_print( root->avl_left, depth + 1 );
  }
  
  static char* priv2str[] = {
  	"privileged",
  	"privileged/TLS",
  	"anonymous",
  	"anonymous/TLS",
  	"bind",
  	"bind/TLS",
  	NULL
  };
  
  void
  ldap_back_print_conntree( ldapinfo_t *li, char *msg )
  {
  	int	c;
  
  	fprintf( stderr, "========> %s\n", msg );
  
  	for ( c = LDAP_BACK_PCONN_FIRST; c < LDAP_BACK_PCONN_LAST; c++ ) {
  		int		i = 0;
  		ldapconn_t	*lc;
  
  		fprintf( stderr, "  %s[%d]\n", priv2str[ c ], li->li_conn_priv[ c ].lic_num );
  
  		LDAP_TAILQ_FOREACH( lc, &li->li_conn_priv[ c ].lic_priv, lc_q )
  		{
  			fprintf( stderr, "    [%d] ", i );
  			ldap_back_conn_print( lc, "" );
  			i++;
  		}
  	}
  	
  	if ( li->li_conninfo.lai_tree == 0 ) {
  		fprintf( stderr, "\t(empty)\n" );
  
  	} else {
  		ldap_back_ravl_print( li->li_conninfo.lai_tree, 0 );
  	}
  	
  	fprintf( stderr, "<======== %s\n", msg );
  }
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  static int
  ldap_back_freeconn( ldapinfo_t *li, ldapconn_t *lc, int dolock );
  
  static ldapconn_t *
  ldap_back_getconn( Operation *op, SlapReply *rs, ldap_back_send_t sendok,
  	struct berval *binddn, struct berval *bindcred );
  
  static int
  ldap_back_is_proxy_authz( Operation *op, SlapReply *rs, ldap_back_send_t sendok,
  	struct berval *binddn, struct berval *bindcred );
  
  static int
  ldap_back_proxy_authz_bind( ldapconn_t *lc, Operation *op, SlapReply *rs,
  	ldap_back_send_t sendok, struct berval *binddn, struct berval *bindcred );
  
  static int
  ldap_back_prepare_conn( ldapconn_t *lc, Operation *op, SlapReply *rs,
  	ldap_back_send_t sendok );
  
  static int
  ldap_back_conndnlc_cmp( const void *c1, const void *c2 );
  
  ldapconn_t *
  ldap_back_conn_delete( ldapinfo_t *li, ldapconn_t *lc )
  {
  	if ( LDAP_BACK_PCONN_ISPRIV( lc ) ) {
  		if ( LDAP_BACK_CONN_CACHED( lc ) ) {
  			assert( lc->lc_q.tqe_prev != NULL );
  			assert( li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_num > 0 );
  			li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_num--;
  			LDAP_TAILQ_REMOVE( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_priv, lc, lc_q );
  			LDAP_TAILQ_ENTRY_INIT( lc, lc_q );
  			LDAP_BACK_CONN_CACHED_CLEAR( lc );
  
  		} else {
  			assert( LDAP_BACK_CONN_TAINTED( lc ) );
  			assert( lc->lc_q.tqe_prev == NULL );
  		}
  
  	} else {
  		ldapconn_t	*tmplc = NULL;
  
  		if ( LDAP_BACK_CONN_CACHED( lc ) ) {
  			assert( !LDAP_BACK_CONN_TAINTED( lc ) );
  			tmplc = avl_delete( &li->li_conninfo.lai_tree, (caddr_t)lc,
  				ldap_back_conndnlc_cmp );
  			assert( tmplc == lc );
  			LDAP_BACK_CONN_CACHED_CLEAR( lc );
  		}
  
  		assert( LDAP_BACK_CONN_TAINTED( lc ) || tmplc == lc );
  	}
  
  	return lc;
  }
  
  int
  ldap_back_bind( Operation *op, SlapReply *rs )
  {
  	ldapinfo_t		*li = (ldapinfo_t *) op->o_bd->be_private;
  	ldapconn_t		*lc;
  
  	LDAPControl		**ctrls = NULL;
  	struct berval		save_o_dn;
  	int			save_o_do_not_cache,
  				rc = 0;
  	ber_int_t		msgid;
  	ldap_back_send_t	retrying = LDAP_BACK_RETRYING;
  
  	/* allow rootdn as a means to auth without the need to actually
   	 * contact the proxied DSA */
  	switch ( be_rootdn_bind( op, rs ) ) {
  	case SLAP_CB_CONTINUE:
  		break;
  
  	default:
  		return rs->sr_err;
  	}
  
  	lc = ldap_back_getconn( op, rs, LDAP_BACK_BIND_SERR, NULL, NULL );
  	if ( !lc ) {
  		return rs->sr_err;
  	}
  
  	/* we can do (almost) whatever we want with this conn,
  	 * because either it's temporary, or it's marked as binding */
  	if ( !BER_BVISNULL( &lc->lc_bound_ndn ) ) {
  		ch_free( lc->lc_bound_ndn.bv_val );
  		BER_BVZERO( &lc->lc_bound_ndn );
  	}
  	if ( !BER_BVISNULL( &lc->lc_cred ) ) {
  		memset( lc->lc_cred.bv_val, 0, lc->lc_cred.bv_len );
  		ch_free( lc->lc_cred.bv_val );
  		BER_BVZERO( &lc->lc_cred );
  	}
  	LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  
  	/* don't add proxyAuthz; set the bindDN */
  	save_o_dn = op->o_dn;
  	save_o_do_not_cache = op->o_do_not_cache;
  	op->o_dn = op->o_req_dn;
  	op->o_do_not_cache = 1;
  
  	ctrls = op->o_ctrls;
  	rc = ldap_back_controls_add( op, rs, lc, &ctrls );
  	op->o_dn = save_o_dn;
  	op->o_do_not_cache = save_o_do_not_cache;
  	if ( rc != LDAP_SUCCESS ) {
  		send_ldap_result( op, rs );
  		ldap_back_release_conn( li, lc );
  		return( rc );
  	}
  
  retry:;
  	/* method is always LDAP_AUTH_SIMPLE if we got here */
  	rs->sr_err = ldap_sasl_bind( lc->lc_ld, op->o_req_dn.bv_val,
  			LDAP_SASL_SIMPLE,
  			&op->orb_cred, ctrls, NULL, &msgid );
  	/* FIXME: should we always retry, or only when piping the bind
  	 * in the "override" connection pool? */
  	rc = ldap_back_op_result( lc, op, rs, msgid,
  		li->li_timeout[ SLAP_OP_BIND ],
  		LDAP_BACK_BIND_SERR | retrying );
  	if ( rc == LDAP_UNAVAILABLE && retrying ) {
  		retrying &= ~LDAP_BACK_RETRYING;
  		if ( ldap_back_retry( &lc, op, rs, LDAP_BACK_BIND_SERR ) ) {
  			goto retry;
  		}
  	}
  
  	ldap_pvt_thread_mutex_lock( &li->li_counter_mutex );
  	ldap_pvt_mp_add( li->li_ops_completed[ SLAP_OP_BIND ], 1 );
  	ldap_pvt_thread_mutex_unlock( &li->li_counter_mutex );
  
  	ldap_back_controls_free( op, rs, &ctrls );
  
  	if ( rc == LDAP_SUCCESS ) {
  		op->o_conn->c_authz_cookie = op->o_bd->be_private;
  
  		/* If defined, proxyAuthz will be used also when
  		 * back-ldap is the authorizing backend; for this
  		 * purpose, after a successful bind the connection
  		 * is left for further binds, and further operations 
  		 * on this client connection will use a default
  		 * connection with identity assertion */
  		/* NOTE: use with care */
  		if ( li->li_idassert_flags & LDAP_BACK_AUTH_OVERRIDE ) {
  			ldap_back_release_conn( li, lc );
  			return( rc );
  		}
  
  		/* rebind is now done inside ldap_back_proxy_authz_bind()
  		 * in case of success */
  		LDAP_BACK_CONN_ISBOUND_SET( lc );
  		ber_dupbv( &lc->lc_bound_ndn, &op->o_req_ndn );
  
  		if ( !BER_BVISNULL( &lc->lc_cred ) ) {
  			memset( lc->lc_cred.bv_val, 0,
  					lc->lc_cred.bv_len );
  		}
  
  		if ( LDAP_BACK_SAVECRED( li ) ) {
  			ber_bvreplace( &lc->lc_cred, &op->orb_cred );
  			ldap_set_rebind_proc( lc->lc_ld, li->li_rebind_f, lc );
  
  		} else {
  			lc->lc_cred.bv_len = 0;
  		}
  	}
  
  	/* must re-insert if local DN changed as result of bind */
  	if ( !LDAP_BACK_CONN_ISBOUND( lc )
  		|| ( !dn_match( &op->o_req_ndn, &lc->lc_local_ndn )
  			&& !LDAP_BACK_PCONN_ISPRIV( lc ) ) )
  	{
  		int		lerr = -1;
  		ldapconn_t	*tmplc;
  
  		/* wait for all other ops to release the connection */
  retry_lock:;
  		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  		if ( lc->lc_refcnt > 1 ) {
  			ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  			ldap_pvt_thread_yield();
  			goto retry_lock;
  		}
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  		ldap_back_print_conntree( li, ">>> ldap_back_bind" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  		assert( lc->lc_refcnt == 1 );
  		ldap_back_conn_delete( li, lc );
  
  		/* delete all cached connections with the current connection */
  		if ( LDAP_BACK_SINGLECONN( li ) ) {
  			while ( ( tmplc = avl_delete( &li->li_conninfo.lai_tree, (caddr_t)lc, ldap_back_conn_cmp ) ) != NULL )
  			{
  				assert( !LDAP_BACK_PCONN_ISPRIV( lc ) );
  				Debug( LDAP_DEBUG_TRACE,
  					"=>ldap_back_bind: destroying conn %lu (refcnt=%u)\n",
  					lc->lc_conn->c_connid, lc->lc_refcnt, 0 );
  
  				if ( tmplc->lc_refcnt != 0 ) {
  					/* taint it */
  					LDAP_BACK_CONN_TAINTED_SET( tmplc );
  					LDAP_BACK_CONN_CACHED_CLEAR( tmplc );
  
  				} else {
  					/*
  					 * Needs a test because the handler may be corrupted,
  					 * and calling ldap_unbind on a corrupted header results
  					 * in a segmentation fault
  					 */
  					ldap_back_conn_free( tmplc );
  				}
  			}
  		}
  
  		if ( LDAP_BACK_CONN_ISBOUND( lc ) ) {
  			ber_bvreplace( &lc->lc_local_ndn, &op->o_req_ndn );
  			if ( be_isroot_dn( op->o_bd, &op->o_req_ndn ) ) {
  				LDAP_BACK_PCONN_ROOTDN_SET( lc, op );
  			}
  			lerr = avl_insert( &li->li_conninfo.lai_tree, (caddr_t)lc,
  				ldap_back_conndn_cmp, ldap_back_conndn_dup );
  		}
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  		ldap_back_print_conntree( li, "<<< ldap_back_bind" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  	
  		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  		switch ( lerr ) {
  		case 0:
  			LDAP_BACK_CONN_CACHED_SET( lc );
  			break;
  
  		case -1:
  			/* duplicate; someone else successfully bound
  			 * on the same connection with the same identity;
  			 * we can do this because lc_refcnt == 1 */
  			ldap_back_conn_free( lc );
  			lc = NULL;
  		}
  	}
  
  	if ( lc != NULL ) {
  		ldap_back_release_conn( li, lc );
  	}
  
  	return( rc );
  }
  
  /*
   * ldap_back_conndn_cmp
   *
   * compares two ldapconn_t based on the value of the conn pointer
   * and of the local DN; used by avl stuff for insert, lookup
   * and direct delete
   */
  int
  ldap_back_conndn_cmp( const void *c1, const void *c2 )
  {
  	const ldapconn_t	*lc1 = (const ldapconn_t *)c1;
  	const ldapconn_t	*lc2 = (const ldapconn_t *)c2;
  	int rc;
  
  	/* If local DNs don't match, it is definitely not a match */
  	/* For shared sessions, conn is NULL. Only explicitly
  	 * bound sessions will have non-NULL conn.
  	 */
  	rc = SLAP_PTRCMP( lc1->lc_conn, lc2->lc_conn );
  	if ( rc == 0 ) {
  		rc = ber_bvcmp( &lc1->lc_local_ndn, &lc2->lc_local_ndn );
  	}
  
  	return rc;
  }
  
  /*
   * ldap_back_conndnlc_cmp
   *
   * compares two ldapconn_t based on the value of the conn pointer,
   * the local DN and the lc pointer; used by avl stuff for insert, lookup
   * and direct delete
   */
  static int
  ldap_back_conndnlc_cmp( const void *c1, const void *c2 )
  {
  	const ldapconn_t	*lc1 = (const ldapconn_t *)c1;
  	const ldapconn_t	*lc2 = (const ldapconn_t *)c2;
  	int rc;
  
  	/* If local DNs don't match, it is definitely not a match */
  	/* For shared sessions, conn is NULL. Only explicitly
  	 * bound sessions will have non-NULL conn.
  	 */
  	rc = SLAP_PTRCMP( lc1->lc_conn, lc2->lc_conn );
  	if ( rc == 0 ) {
  		rc = ber_bvcmp( &lc1->lc_local_ndn, &lc2->lc_local_ndn );
  		if ( rc == 0 ) {
  			rc = SLAP_PTRCMP( lc1, lc2 );
  		}
  	}
  
  	return rc;
  }
  
  /*
   * ldap_back_conn_cmp
   *
   * compares two ldapconn_t based on the value of the conn pointer;
   * used by avl stuff for delete of all conns with the same connid
   */
  int
  ldap_back_conn_cmp( const void *c1, const void *c2 )
  {
  	const ldapconn_t	*lc1 = (const ldapconn_t *)c1;
  	const ldapconn_t	*lc2 = (const ldapconn_t *)c2;
  
  	/* For shared sessions, conn is NULL. Only explicitly
  	 * bound sessions will have non-NULL conn.
  	 */
  	return SLAP_PTRCMP( lc1->lc_conn, lc2->lc_conn );
  }
  
  /*
   * ldap_back_conndn_dup
   *
   * returns -1 in case a duplicate ldapconn_t has been inserted;
   * used by avl stuff
   */
  int
  ldap_back_conndn_dup( void *c1, void *c2 )
  {
  	ldapconn_t	*lc1 = (ldapconn_t *)c1;
  	ldapconn_t	*lc2 = (ldapconn_t *)c2;
  
  	/* Cannot have more than one shared session with same DN */
  	if ( lc1->lc_conn == lc2->lc_conn &&
  		dn_match( &lc1->lc_local_ndn, &lc2->lc_local_ndn ) )
  	{
  		return -1;
  	}
  		
  	return 0;
  }
  
  static int
  ldap_back_freeconn( ldapinfo_t *li, ldapconn_t *lc, int dolock )
  {
  	if ( dolock ) {
  		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  	}
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  	ldap_back_print_conntree( li, ">>> ldap_back_freeconn" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  	(void)ldap_back_conn_delete( li, lc );
  
  	if ( lc->lc_refcnt == 0 ) {
  		ldap_back_conn_free( (void *)lc );
  	}
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  	ldap_back_print_conntree( li, "<<< ldap_back_freeconn" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  	if ( dolock ) {
  		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  	}
  
  	return 0;
  }
  
  #ifdef HAVE_TLS
  static int
  ldap_back_start_tls(
  	LDAP		*ld,
  	int		protocol,
  	int		*is_tls,
  	const char	*url,
  	unsigned	flags,
  	int		retries,
  	const char	**text )
  {
  	int		rc = LDAP_SUCCESS;
  
  	/* start TLS ("tls-[try-]{start,propagate}" statements) */
  	if ( ( LDAP_BACK_USE_TLS_F( flags ) || ( *is_tls && LDAP_BACK_PROPAGATE_TLS_F( flags ) ) )
  				&& !ldap_is_ldaps_url( url ) )
  	{
  #ifdef SLAP_STARTTLS_ASYNCHRONOUS
  		/*
  		 * use asynchronous StartTLS
  		 * in case, chase referral (not implemented yet)
  		 */
  		int		msgid;
  
  		if ( protocol == 0 ) {
  			ldap_get_option( ld, LDAP_OPT_PROTOCOL_VERSION,
  					(void *)&protocol );
  		}
  
  		if ( protocol < LDAP_VERSION3 ) {
  			/* we should rather bail out... */
  			rc = LDAP_UNWILLING_TO_PERFORM;
  			*text = "invalid protocol version";
  		}
  
  		if ( rc == LDAP_SUCCESS ) {
  			rc = ldap_start_tls( ld, NULL, NULL, &msgid );
  		}
  
  		if ( rc == LDAP_SUCCESS ) {
  			LDAPMessage	*res = NULL;
  			struct timeval	tv;
  
  			LDAP_BACK_TV_SET( &tv );
  
  retry:;
  			rc = ldap_result( ld, msgid, LDAP_MSG_ALL, &tv, &res );
  			if ( rc < 0 ) {
  				rc = LDAP_UNAVAILABLE;
  
  			} else if ( rc == 0 ) {
  				if ( retries != LDAP_BACK_RETRY_NEVER ) {
  					ldap_pvt_thread_yield();
  					if ( retries > 0 ) {
  						retries--;
  					}
  					LDAP_BACK_TV_SET( &tv );
  					goto retry;
  				}
  				rc = LDAP_UNAVAILABLE;
  
  			} else if ( rc == LDAP_RES_EXTENDED ) {
  				struct berval	*data = NULL;
  
  				rc = ldap_parse_extended_result( ld, res,
  						NULL, &data, 0 );
  				if ( rc == LDAP_SUCCESS ) {
  					SlapReply rs;
  					rc = ldap_parse_result( ld, res, &rs.sr_err,
  						NULL, NULL, NULL, NULL, 1 );
  					if ( rc != LDAP_SUCCESS ) {
  						rs.sr_err = rc;
  					}
  					rc = slap_map_api2result( &rs );
  					res = NULL;
  					
  					/* FIXME: in case a referral 
  					 * is returned, should we try
  					 * using it instead of the 
  					 * configured URI? */
  					if ( rc == LDAP_SUCCESS ) {
  						rc = ldap_install_tls( ld );
  
  					} else if ( rc == LDAP_REFERRAL ) {
  						rc = LDAP_UNWILLING_TO_PERFORM;
  						*text = "unwilling to chase referral returned by Start TLS exop";
  					}
  
  					if ( data ) {
  						if ( data->bv_val ) {
  							ber_memfree( data->bv_val );
  						}
  						ber_memfree( data );
  					}
  				}
  
  			} else {
  				rc = LDAP_OTHER;
  			}
  
  			if ( res != NULL ) {
  				ldap_msgfree( res );
  			}
  		}
  #else /* ! SLAP_STARTTLS_ASYNCHRONOUS */
  		/*
  		 * use synchronous StartTLS
  		 */
  		rc = ldap_start_tls_s( ld, NULL, NULL );
  #endif /* ! SLAP_STARTTLS_ASYNCHRONOUS */
  
  		/* if StartTLS is requested, only attempt it if the URL
  		 * is not "ldaps://"; this may occur not only in case
  		 * of misconfiguration, but also when used in the chain 
  		 * overlay, where the "uri" can be parsed out of a referral */
  		switch ( rc ) {
  		case LDAP_SUCCESS:
  			*is_tls = 1;
  			break;
  
  		case LDAP_SERVER_DOWN:
  			break;
  
  		default:
  			if ( LDAP_BACK_TLS_CRITICAL_F( flags ) ) {
  				*text = "could not start TLS";
  				break;
  			}
  
  			/* in case Start TLS is not critical */
  			*is_tls = 0;
  			rc = LDAP_SUCCESS;
  			break;
  		}
  
  	} else {
  		*is_tls = 0;
  	}
  
  	return rc;
  }
  #endif /* HAVE_TLS */
  
  static int
  ldap_back_prepare_conn( ldapconn_t *lc, Operation *op, SlapReply *rs, ldap_back_send_t sendok )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  	int		version;
  	LDAP		*ld = NULL;
  #ifdef HAVE_TLS
  	int		is_tls = op->o_conn->c_is_tls;
  	int		flags = li->li_flags;
  	time_t		lctime = (time_t)(-1);
  	slap_bindconf *sb;
  #endif /* HAVE_TLS */
  
  	ldap_pvt_thread_mutex_lock( &li->li_uri_mutex );
  	rs->sr_err = ldap_initialize( &ld, li->li_uri );
  	ldap_pvt_thread_mutex_unlock( &li->li_uri_mutex );
  	if ( rs->sr_err != LDAP_SUCCESS ) {
  		goto error_return;
  	}
  
  	if ( li->li_urllist_f ) {
  		ldap_set_urllist_proc( ld, li->li_urllist_f, li->li_urllist_p );
  	}
  
  	/* Set LDAP version. This will always succeed: If the client
  	 * bound with a particular version, then so can we.
  	 */
  	if ( li->li_version != 0 ) {
  		version = li->li_version;
  
  	} else if ( op->o_protocol != 0 ) {
  		version = op->o_protocol;
  
  	} else {
  		/* assume it's an internal op; set to LDAPv3 */
  		version = LDAP_VERSION3;
  	}
  	ldap_set_option( ld, LDAP_OPT_PROTOCOL_VERSION, (const void *)&version );
  
  	/* automatically chase referrals ("chase-referrals [{yes|no}]" statement) */
  	ldap_set_option( ld, LDAP_OPT_REFERRALS,
  		LDAP_BACK_CHASE_REFERRALS( li ) ? LDAP_OPT_ON : LDAP_OPT_OFF );
  
  	if ( li->li_network_timeout > 0 ) {
  		struct timeval		tv;
  
  		tv.tv_sec = li->li_network_timeout;
  		tv.tv_usec = 0;
  		ldap_set_option( ld, LDAP_OPT_NETWORK_TIMEOUT, (const void *)&tv );
  	}
  
  #ifdef HAVE_TLS
  	if ( LDAP_BACK_CONN_ISPRIV( lc ) ) {
  		/* See "rationale" comment in ldap_back_getconn() */
  		if ( li->li_acl_authmethod == LDAP_AUTH_NONE &&
  			 li->li_idassert_authmethod != LDAP_AUTH_NONE )
  			sb = &li->li_idassert.si_bc;
  		else
  			sb = &li->li_acl;
  
  	} else if ( LDAP_BACK_CONN_ISIDASSERT( lc ) ) {
  		sb = &li->li_idassert.si_bc;
  
  	} else {
  		sb = &li->li_tls;
  	}
  
  	if ( sb->sb_tls_do_init ) {
  		bindconf_tls_set( sb, ld );
  	} else if ( sb->sb_tls_ctx ) {
  		ldap_set_option( ld, LDAP_OPT_X_TLS_CTX, sb->sb_tls_ctx );
  	}
  
  	/* if required by the bindconf configuration, force TLS */
  	if ( ( sb == &li->li_acl || sb == &li->li_idassert.si_bc ) &&
  		sb->sb_tls_ctx )
  	{
  		flags |= LDAP_BACK_F_USE_TLS;
  	}
  
  	ldap_pvt_thread_mutex_lock( &li->li_uri_mutex );
  	assert( li->li_uri_mutex_do_not_lock == 0 );
  	li->li_uri_mutex_do_not_lock = 1;
  	rs->sr_err = ldap_back_start_tls( ld, op->o_protocol, &is_tls,
  			li->li_uri, flags, li->li_nretries, &rs->sr_text );
  	li->li_uri_mutex_do_not_lock = 0;
  	ldap_pvt_thread_mutex_unlock( &li->li_uri_mutex );
  	if ( rs->sr_err != LDAP_SUCCESS ) {
  		ldap_unbind_ext( ld, NULL, NULL );
  		rs->sr_text = "Start TLS failed";
  		goto error_return;
  
  	} else if ( li->li_idle_timeout ) {
  		/* only touch when activity actually took place... */
  		lctime = op->o_time;
  	}
  #endif /* HAVE_TLS */
  
  	lc->lc_ld = ld;
  	lc->lc_refcnt = 1;
  #ifdef HAVE_TLS
  	if ( is_tls ) {
  		LDAP_BACK_CONN_ISTLS_SET( lc );
  	} else {
  		LDAP_BACK_CONN_ISTLS_CLEAR( lc );
  	}
  	if ( lctime != (time_t)(-1) ) {
  		lc->lc_time = lctime;
  	}
  #endif /* HAVE_TLS */
  
  error_return:;
  	if ( rs->sr_err != LDAP_SUCCESS ) {
  		rs->sr_err = slap_map_api2result( rs );
  		if ( sendok & LDAP_BACK_SENDERR ) {
  			if ( rs->sr_text == NULL ) {
  				rs->sr_text = "Proxy connection initialization failed";
  			}
  			send_ldap_result( op, rs );
  		}
  
  	} else {
  		if ( li->li_conn_ttl > 0 ) {
  			lc->lc_create_time = op->o_time;
  		}
  	}
  
  	return rs->sr_err;
  }
  
  static ldapconn_t *
  ldap_back_getconn(
  	Operation		*op,
  	SlapReply		*rs,
  	ldap_back_send_t	sendok,
  	struct berval		*binddn,
  	struct berval		*bindcred )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  	ldapconn_t	*lc = NULL,
  			lc_curr = {{ 0 }};
  	int		refcnt = 1,
  			lookupconn = !( sendok & LDAP_BACK_BINDING );
  
  	/* if the server is quarantined, and
  	 * - the current interval did not expire yet, or
  	 * - no more retries should occur,
  	 * don't return the connection */
  	if ( li->li_isquarantined ) {
  		slap_retry_info_t	*ri = &li->li_quarantine;
  		int			dont_retry = 1;
  
  		if ( li->li_quarantine.ri_interval ) {
  			ldap_pvt_thread_mutex_lock( &li->li_quarantine_mutex );
  			if ( li->li_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 ) {
  					Debug( LDAP_DEBUG_ANY,
  						"%s: ldap_back_getconn quarantine "
  						"retry block #%d try #%d.\n",
  						op->o_log_prefix, ri->ri_idx, ri->ri_count );
  					li->li_isquarantined = LDAP_BACK_FQ_RETRYING;
  				}
  			}
  			ldap_pvt_thread_mutex_unlock( &li->li_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 NULL;
  		}
  	}
  
  	/* Internal searches are privileged and shared. So is root. */
  	if ( op->o_do_not_cache || be_isroot( op ) ) {
  		LDAP_BACK_CONN_ISPRIV_SET( &lc_curr );
  		lc_curr.lc_local_ndn = op->o_bd->be_rootndn;
  		LDAP_BACK_PCONN_ROOTDN_SET( &lc_curr, op );
  
  	} else {
  		struct berval	tmpbinddn,
  				tmpbindcred,
  				save_o_dn,
  				save_o_ndn;
  		int		isproxyauthz;
  
  		/* need cleanup */
  		if ( binddn == NULL ) {
  			binddn = &tmpbinddn;
  		}	
  		if ( bindcred == NULL ) {
  			bindcred = &tmpbindcred;
  		}
  		if ( op->o_tag == LDAP_REQ_BIND ) {
  			save_o_dn = op->o_dn;
  			save_o_ndn = op->o_ndn;
  			op->o_dn = op->o_req_dn;
  			op->o_ndn = op->o_req_ndn;
  		}
  		isproxyauthz = ldap_back_is_proxy_authz( op, rs, sendok, binddn, bindcred );
  		if ( op->o_tag == LDAP_REQ_BIND ) {
  			op->o_dn = save_o_dn;
  			op->o_ndn = save_o_ndn;
  		}
  		if ( isproxyauthz == -1 ) {
  			return NULL;
  		}
  
  		lc_curr.lc_local_ndn = op->o_ndn;
  		/* Explicit binds must not be shared;
  		 * however, explicit binds are piped in a special connection
  		 * when idassert is to occur with "override" set */
  		if ( op->o_tag == LDAP_REQ_BIND && !isproxyauthz ) {
  			lc_curr.lc_conn = op->o_conn;
  
  		} else {
  			if ( isproxyauthz && !( sendok & LDAP_BACK_BINDING ) ) {
  				lc_curr.lc_local_ndn = *binddn;
  				LDAP_BACK_PCONN_ROOTDN_SET( &lc_curr, op );
  				LDAP_BACK_CONN_ISIDASSERT_SET( &lc_curr );
  
  			} else if ( isproxyauthz && ( li->li_idassert_flags & LDAP_BACK_AUTH_OVERRIDE ) ) {
  				lc_curr.lc_local_ndn = slap_empty_bv;
  				LDAP_BACK_PCONN_BIND_SET( &lc_curr, op );
  				LDAP_BACK_CONN_ISIDASSERT_SET( &lc_curr );
  				lookupconn = 1;
  
  			} else if ( SLAP_IS_AUTHZ_BACKEND( op ) ) {
  				lc_curr.lc_conn = op->o_conn;
  
  			} else {
  				LDAP_BACK_PCONN_ANON_SET( &lc_curr, op );
  			}
  		}
  	}
  
  	/* Explicit Bind requests always get their own conn */
  	if ( lookupconn ) {
  retry_lock:
  		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  		if ( LDAP_BACK_PCONN_ISPRIV( &lc_curr ) ) {
  			/* lookup a conn that's not binding */
  			LDAP_TAILQ_FOREACH( lc,
  				&li->li_conn_priv[ LDAP_BACK_CONN2PRIV( &lc_curr ) ].lic_priv,
  				lc_q )
  			{
  				if ( !LDAP_BACK_CONN_BINDING( lc ) && lc->lc_refcnt == 0 ) {
  					break;
  				}
  			}
  
  			if ( lc != NULL ) {
  				if ( lc != LDAP_TAILQ_LAST( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_priv,
  					ldapconn_t, lc_q ) )
  				{
  					LDAP_TAILQ_REMOVE( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_priv,
  						lc, lc_q );
  					LDAP_TAILQ_ENTRY_INIT( lc, lc_q );
  					LDAP_TAILQ_INSERT_TAIL( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_priv,
  						lc, lc_q );
  				}
  
  			} else if ( !LDAP_BACK_USE_TEMPORARIES( li )
  				&& li->li_conn_priv[ LDAP_BACK_CONN2PRIV( &lc_curr ) ].lic_num == li->li_conn_priv_max )
  			{
  				lc = LDAP_TAILQ_FIRST( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( &lc_curr ) ].lic_priv );
  			}
  			
  		} else {
  
  			/* Searches for a ldapconn in the avl tree */
  			lc = (ldapconn_t *)avl_find( li->li_conninfo.lai_tree, 
  					(caddr_t)&lc_curr, ldap_back_conndn_cmp );
  		}
  
  		if ( lc != NULL ) {
  			/* Don't reuse connections while they're still binding */
  			if ( LDAP_BACK_CONN_BINDING( lc ) ) {
  				if ( !LDAP_BACK_USE_TEMPORARIES( li ) ) {
  					ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  
  					ldap_pvt_thread_yield();
  					goto retry_lock;
  				}
  				lc = NULL;
  			}
  
  			if ( lc != NULL ) {
  				if ( op->o_tag == LDAP_REQ_BIND ) {
  					/* right now, this is the only possible case */
  					assert( ( li->li_idassert_flags & LDAP_BACK_AUTH_OVERRIDE ) );
  					LDAP_BACK_CONN_BINDING_SET( lc );
  				}
  
  				refcnt = ++lc->lc_refcnt;
  			}
  		}
  		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  	}
  
  	/* Looks like we didn't get a bind. Open a new session... */
  	if ( lc == NULL ) {
  		lc = (ldapconn_t *)ch_calloc( 1, sizeof( ldapconn_t ) );
  		lc->lc_flags = li->li_flags;
  		lc->lc_lcflags = lc_curr.lc_lcflags;
  		if ( ldap_back_prepare_conn( lc, op, rs, sendok ) != LDAP_SUCCESS ) {
  			ch_free( lc );
  			return NULL;
  		}
  
  		if ( sendok & LDAP_BACK_BINDING ) {
  			LDAP_BACK_CONN_BINDING_SET( lc );
  		}
  
  		lc->lc_conn = lc_curr.lc_conn;
  		ber_dupbv( &lc->lc_local_ndn, &lc_curr.lc_local_ndn );
  
  		/*
  		 * the rationale is: connections as the rootdn are privileged,
  		 * so li_acl is to be used; however, in some cases
  		 * one already configured identity assertion with a highly
  		 * privileged idassert_authcDN, so if li_acl is not configured
  		 * and idassert is, use idassert instead.
  		 *
  		 * might change in the future, because it's preferable
  		 * to make clear what identity is being used, since
  		 * the only drawback is that one risks to configure
  		 * the same identity twice...
  		 */
  		if ( LDAP_BACK_CONN_ISPRIV( &lc_curr ) ) {
  			if ( li->li_acl_authmethod == LDAP_AUTH_NONE &&
  				 li->li_idassert_authmethod != LDAP_AUTH_NONE ) {
  				ber_dupbv( &lc->lc_bound_ndn, &li->li_idassert_authcDN );
  				ber_dupbv( &lc->lc_cred, &li->li_idassert_passwd );
  
  			} else {
  				ber_dupbv( &lc->lc_bound_ndn, &li->li_acl_authcDN );
  				ber_dupbv( &lc->lc_cred, &li->li_acl_passwd );
  			}
  			LDAP_BACK_CONN_ISPRIV_SET( lc );
  
  		} else if ( LDAP_BACK_CONN_ISIDASSERT( &lc_curr ) ) {
  			if ( !LDAP_BACK_PCONN_ISBIND( &lc_curr ) ) {
  				ber_dupbv( &lc->lc_bound_ndn, &li->li_idassert_authcDN );
  				ber_dupbv( &lc->lc_cred, &li->li_idassert_passwd );
  			}
  			LDAP_BACK_CONN_ISIDASSERT_SET( lc );
  
  		} else {
  			BER_BVZERO( &lc->lc_cred );
  			BER_BVZERO( &lc->lc_bound_ndn );
  			if ( !BER_BVISEMPTY( &op->o_ndn )
  				&& SLAP_IS_AUTHZ_BACKEND( op ) )
  			{
  				ber_dupbv( &lc->lc_bound_ndn, &op->o_ndn );
  			}
  		}
  
  #ifdef HAVE_TLS
  		/* if start TLS failed but it was not mandatory,
  		 * check if the non-TLS connection was already
  		 * in cache; in case, destroy the newly created
  		 * connection and use the existing one */
  		if ( LDAP_BACK_PCONN_ISTLS( lc ) 
  				&& !ldap_tls_inplace( lc->lc_ld ) )
  		{
  			ldapconn_t	*tmplc = NULL;
  			int		idx = LDAP_BACK_CONN2PRIV( &lc_curr ) - 1;
  			
  			ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  			LDAP_TAILQ_FOREACH( tmplc,
  				&li->li_conn_priv[ idx ].lic_priv,
  				lc_q )
  			{
  				if ( !LDAP_BACK_CONN_BINDING( tmplc ) ) {
  					break;
  				}
  			}
  
  			if ( tmplc != NULL ) {
  				refcnt = ++tmplc->lc_refcnt;
  				ldap_back_conn_free( lc );
  				lc = tmplc;
  			}
  			ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  
  			if ( tmplc != NULL ) {
  				goto done;
  			}
  		}
  #endif /* HAVE_TLS */
  
  		/* Inserts the newly created ldapconn in the avl tree */
  		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  
  		LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  		lc->lc_connid = li->li_conn_nextid++;
  
  		assert( lc->lc_refcnt == 1 );
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  		ldap_back_print_conntree( li, ">>> ldap_back_getconn(insert)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  	
  		if ( LDAP_BACK_PCONN_ISPRIV( lc ) ) {
  			if ( li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_num < li->li_conn_priv_max ) {
  				LDAP_TAILQ_INSERT_TAIL( &li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_priv, lc, lc_q );
  				li->li_conn_priv[ LDAP_BACK_CONN2PRIV( lc ) ].lic_num++;
  				LDAP_BACK_CONN_CACHED_SET( lc );
  
  			} else {
  				LDAP_BACK_CONN_TAINTED_SET( lc );
  			}
  			rs->sr_err = 0;
  
  		} else {
  			rs->sr_err = avl_insert( &li->li_conninfo.lai_tree, (caddr_t)lc,
  				ldap_back_conndn_cmp, ldap_back_conndn_dup );
  			LDAP_BACK_CONN_CACHED_SET( lc );
  		}
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  		ldap_back_print_conntree( li, "<<< ldap_back_getconn(insert)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  	
  		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  
  		if ( LogTest( LDAP_DEBUG_TRACE ) ) {
  			char	buf[ SLAP_TEXT_BUFLEN ];
  
  			snprintf( buf, sizeof( buf ),
  				"lc=%p inserted refcnt=%u rc=%d",
  				(void *)lc, refcnt, rs->sr_err );
  				
  			Debug( LDAP_DEBUG_TRACE,
  				"=>ldap_back_getconn: %s: %s\n",
  				op->o_log_prefix, buf, 0 );
  		}
  	
  		if ( !LDAP_BACK_PCONN_ISPRIV( lc ) ) {
  			/* Err could be -1 in case a duplicate ldapconn is inserted */
  			switch ( rs->sr_err ) {
  			case 0:
  				break;
  
  			case -1:
  				LDAP_BACK_CONN_CACHED_CLEAR( lc );
  				if ( !( sendok & LDAP_BACK_BINDING ) && !LDAP_BACK_USE_TEMPORARIES( li ) ) {
  					/* duplicate: free and try to get the newly created one */
  					ldap_back_conn_free( lc );
  					lc = NULL;
  					goto retry_lock;
  				}
  
  				/* taint connection, so that it'll be freed when released */
  				LDAP_BACK_CONN_TAINTED_SET( lc );
  				break;
  
  			default:
  				LDAP_BACK_CONN_CACHED_CLEAR( lc );
  				ldap_back_conn_free( lc );
  				rs->sr_err = LDAP_OTHER;
  				rs->sr_text = "Proxy bind collision";
  				if ( op->o_conn && ( sendok & LDAP_BACK_SENDERR ) ) {
  					send_ldap_result( op, rs );
  				}
  				return NULL;
  			}
  		}
  
  	} else {
  		int	expiring = 0;
  
  		if ( ( li->li_idle_timeout != 0 && op->o_time > lc->lc_time + li->li_idle_timeout )
  			|| ( li->li_conn_ttl != 0 && op->o_time > lc->lc_create_time + li->li_conn_ttl ) )
  		{
  			expiring = 1;
  
  			/* let it be used, but taint/delete it so that 
  			 * no-one else can look it up any further */
  			ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  			ldap_back_print_conntree( li, ">>> ldap_back_getconn(timeout)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  			(void)ldap_back_conn_delete( li, lc );
  			LDAP_BACK_CONN_TAINTED_SET( lc );
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  			ldap_back_print_conntree( li, "<<< ldap_back_getconn(timeout)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  			ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  		}
  
  		if ( LogTest( LDAP_DEBUG_TRACE ) ) {
  			char	buf[ SLAP_TEXT_BUFLEN ];
  
  			snprintf( buf, sizeof( buf ),
  				"conn %p fetched refcnt=%u%s",
  				(void *)lc, refcnt,
  				expiring ? " expiring" : "" );
  			Debug( LDAP_DEBUG_TRACE,
  				"=>ldap_back_getconn: %s.\n", buf, 0, 0 );
  		}
  	}
  
  #ifdef HAVE_TLS
  done:;
  #endif /* HAVE_TLS */
  
  	return lc;
  }
  
  void
  ldap_back_release_conn_lock(
  	ldapinfo_t		*li,
  	ldapconn_t		**lcp,
  	int			dolock )
  {
  
  	ldapconn_t	*lc = *lcp;
  
  	if ( dolock ) {
  		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  	}
  	assert( lc->lc_refcnt > 0 );
  	LDAP_BACK_CONN_BINDING_CLEAR( lc );
  	lc->lc_refcnt--;
  	if ( LDAP_BACK_CONN_TAINTED( lc ) ) {
  		ldap_back_freeconn( li, lc, 0 );
  		*lcp = NULL;
  	}
  	if ( dolock ) {
  		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  	}
  }
  
  void
  ldap_back_quarantine(
  	Operation	*op,
  	SlapReply	*rs )
  {
  	ldapinfo_t		*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	slap_retry_info_t	*ri = &li->li_quarantine;
  
  	ldap_pvt_thread_mutex_lock( &li->li_quarantine_mutex );
  
  	if ( rs->sr_err == LDAP_UNAVAILABLE ) {
  		time_t		new_last = slap_get_time();
  
  		switch ( li->li_isquarantined ) {
  		case LDAP_BACK_FQ_NO:
  			if ( ri->ri_last == new_last ) {
  				goto done;
  			}
  
  			Debug( LDAP_DEBUG_ANY,
  				"%s: ldap_back_quarantine enter.\n",
  				op->o_log_prefix, 0, 0 );
  
  			ri->ri_idx = 0;
  			ri->ri_count = 0;
  			break;
  
  		case LDAP_BACK_FQ_RETRYING:
  			Debug( LDAP_DEBUG_ANY,
  				"%s: ldap_back_quarantine block #%d try #%d failed.\n",
  				op->o_log_prefix, ri->ri_idx, ri->ri_count );
  
  			++ri->ri_count;
  			if ( ri->ri_num[ ri->ri_idx ] != SLAP_RETRYNUM_FOREVER
  				&& ri->ri_count == ri->ri_num[ ri->ri_idx ] )
  			{
  				ri->ri_count = 0;
  				++ri->ri_idx;
  			}
  			break;
  
  		default:
  			break;
  		}
  
  		li->li_isquarantined = LDAP_BACK_FQ_YES;
  		ri->ri_last = new_last;
  
  	} else if ( li->li_isquarantined != LDAP_BACK_FQ_NO ) {
  		if ( ri->ri_last == slap_get_time() ) {
  			goto done;
  		}
  
  		Debug( LDAP_DEBUG_ANY,
  			"%s: ldap_back_quarantine exit (%d) err=%d.\n",
  			op->o_log_prefix, li->li_isquarantined, rs->sr_err );
  
  		if ( li->li_quarantine_f ) {
  			(void)li->li_quarantine_f( li, li->li_quarantine_p );
  		}
  
  		ri->ri_count = 0;
  		ri->ri_idx = 0;
  		li->li_isquarantined = LDAP_BACK_FQ_NO;
  	}
  
  done:;
  	ldap_pvt_thread_mutex_unlock( &li->li_quarantine_mutex );
  }
  
  static int
  ldap_back_dobind_cb(
  	Operation *op,
  	SlapReply *rs
  )
  {
  	ber_tag_t *tptr = op->o_callback->sc_private;
  	op->o_tag = *tptr;
  	rs->sr_tag = slap_req2res( op->o_tag );
  
  	return SLAP_CB_CONTINUE;
  }
  
  /*
   * ldap_back_dobind_int
   *
   * Note: dolock indicates whether li->li_conninfo.lai_mutex must be locked or not
   */
  static int
  ldap_back_dobind_int(
  	ldapconn_t		**lcp,
  	Operation		*op,
  	SlapReply		*rs,
  	ldap_back_send_t	sendok,
  	int			retries,
  	int			dolock )
  {	
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	ldapconn_t	*lc;
  	struct berval	binddn = slap_empty_bv,
  			bindcred = slap_empty_bv;
  
  	int		rc = 0,
  			isbound,
  			binding = 0;
  	ber_int_t	msgid;
  	ber_tag_t	o_tag = op->o_tag;
  	slap_callback cb = {0};
  	char		*tmp_dn;
  
  	assert( lcp != NULL );
  	assert( retries >= 0 );
  
  	if ( sendok & LDAP_BACK_GETCONN ) {
  		assert( *lcp == NULL );
  
  		lc = ldap_back_getconn( op, rs, sendok, &binddn, &bindcred );
  		if ( lc == NULL ) {
  			return 0;
  		}
  		*lcp = lc;
  
  	} else {
  		lc = *lcp;
  	}
  
  	assert( lc != NULL );
  
  retry_lock:;
   	if ( dolock ) {
   		ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
   	}
  
   	if ( binding == 0 ) {
  		/* check if already bound */
  		rc = isbound = LDAP_BACK_CONN_ISBOUND( lc );
  		if ( isbound ) {
   			if ( dolock ) {
   				ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
   			}
  			return rc;
  		}
  
  		if ( LDAP_BACK_CONN_BINDING( lc ) ) {
  			/* if someone else is about to bind it, give up and retry */
   			if ( dolock ) {
   				ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
   			}
  			ldap_pvt_thread_yield();
  			goto retry_lock;
  
  		} else {
  			/* otherwise this thread will bind it */
   			LDAP_BACK_CONN_BINDING_SET( lc );
  			binding = 1;
  		}
  	}
  
   	if ( dolock ) {
   		ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
   	}
  
  	/*
  	 * FIXME: we need to let clients use proxyAuthz
  	 * otherwise we cannot do symmetric pools of servers;
  	 * we have to live with the fact that a user can
  	 * authorize itself as any ID that is allowed
  	 * by the authzTo directive of the "proxyauthzdn".
  	 */
  	/*
  	 * NOTE: current Proxy Authorization specification
  	 * and implementation do not allow proxy authorization
  	 * control to be provided with Bind requests
  	 */
  	/*
  	 * if no bind took place yet, but the connection is bound
  	 * and the "idassert-authcDN" (or other ID) is set, 
  	 * then bind as the asserting identity and explicitly 
  	 * add the proxyAuthz control to every operation with the
  	 * dn bound to the connection as control value.
  	 * This is done also if this is the authorizing backend,
  	 * but the "override" flag is given to idassert.
  	 * It allows to use SASL bind and yet proxyAuthz users
  	 */
  	op->o_tag = LDAP_REQ_BIND;
  	cb.sc_next = op->o_callback;
  	cb.sc_private = &o_tag;
  	cb.sc_response = ldap_back_dobind_cb;
  	op->o_callback = &cb;
  
  	if ( LDAP_BACK_CONN_ISIDASSERT( lc ) ) {
  		if ( BER_BVISEMPTY( &binddn ) && BER_BVISEMPTY( &bindcred ) ) {
  			/* if we got here, it shouldn't return result */
  			rc = ldap_back_is_proxy_authz( op, rs,
  				LDAP_BACK_DONTSEND, &binddn, &bindcred );
  			if ( rc != 1 ) {
  				Debug( LDAP_DEBUG_ANY, "Error: ldap_back_is_proxy_authz "
  					"returned %d, misconfigured URI?\n", rc, 0, 0 );
  				rs->sr_err = LDAP_OTHER;
  				rs->sr_text = "misconfigured URI?";
  				LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  				if ( sendok & LDAP_BACK_SENDERR ) {
  					send_ldap_result( op, rs );
  				}
  				goto done;
  			}
  		}
  		rc = ldap_back_proxy_authz_bind( lc, op, rs, sendok, &binddn, &bindcred );
  		goto done;
  	}
  
  #ifdef HAVE_CYRUS_SASL
  	if ( LDAP_BACK_CONN_ISPRIV( lc )) {
  	slap_bindconf *sb;
  	if ( li->li_acl_authmethod != LDAP_AUTH_NONE )
  		sb = &li->li_acl;
  	else
  		sb = &li->li_idassert.si_bc;
  
  	if ( sb->sb_method == LDAP_AUTH_SASL ) {
  		void		*defaults = NULL;
  
  		if ( sb->sb_secprops != NULL ) {
  			rc = ldap_set_option( lc->lc_ld,
  				LDAP_OPT_X_SASL_SECPROPS, sb->sb_secprops );
  
  			if ( rc != LDAP_OPT_SUCCESS ) {
  				Debug( LDAP_DEBUG_ANY, "Error: ldap_set_option "
  					"(SECPROPS,\"%s\") failed!\n",
  					sb->sb_secprops, 0, 0 );
  				goto done;
  			}
  		}
  
  		defaults = lutil_sasl_defaults( lc->lc_ld,
  				sb->sb_saslmech.bv_val,
  				sb->sb_realm.bv_val,
  				sb->sb_authcId.bv_val,
  				sb->sb_cred.bv_val,
  				NULL );
  		if ( defaults == NULL ) {
  			rs->sr_err = LDAP_OTHER;
  			LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  			if ( sendok & LDAP_BACK_SENDERR ) {
  				send_ldap_result( op, rs );
  			}
  			goto done;
  		}
  
  		rs->sr_err = ldap_sasl_interactive_bind_s( lc->lc_ld,
  				sb->sb_binddn.bv_val,
  				sb->sb_saslmech.bv_val, NULL, NULL,
  				LDAP_SASL_QUIET, lutil_sasl_interact,
  				defaults );
  
  		ldap_pvt_thread_mutex_lock( &li->li_counter_mutex );
  		ldap_pvt_mp_add( li->li_ops_completed[ SLAP_OP_BIND ], 1 );
  		ldap_pvt_thread_mutex_unlock( &li->li_counter_mutex );
  
  		lutil_sasl_freedefs( defaults );
  
  		switch ( rs->sr_err ) {
  		case LDAP_SUCCESS:
  			LDAP_BACK_CONN_ISBOUND_SET( lc );
  			break;
  
  		case LDAP_LOCAL_ERROR:
  			/* list client API error codes that require
  			 * to taint the connection */
  			/* FIXME: should actually retry? */
  			LDAP_BACK_CONN_TAINTED_SET( lc );
  
  			/* fallthru */
  
  		default:
  			LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  			rs->sr_err = slap_map_api2result( rs );
  			if ( sendok & LDAP_BACK_SENDERR ) {
  				send_ldap_result( op, rs );
  			}
  			break;
  		}
  
  		if ( LDAP_BACK_QUARANTINE( li ) ) {
  			ldap_back_quarantine( op, rs );
  		}
  
  		goto done;
  	}
  	}
  #endif /* HAVE_CYRUS_SASL */
  
  retry:;
  	if ( BER_BVISNULL( &lc->lc_cred ) ) {
  		tmp_dn = "";
  		if ( !BER_BVISNULL( &lc->lc_bound_ndn ) && !BER_BVISEMPTY( &lc->lc_bound_ndn ) ) {
  			Debug( LDAP_DEBUG_ANY, "%s ldap_back_dobind_int: DN=\"%s\" without creds, binding anonymously",
  				op->o_log_prefix, lc->lc_bound_ndn.bv_val, 0 );
  		}
  
  	} else {
  		tmp_dn = lc->lc_bound_ndn.bv_val;
  	}
  	rs->sr_err = ldap_sasl_bind( lc->lc_ld,
  			tmp_dn,
  			LDAP_SASL_SIMPLE, &lc->lc_cred,
  			NULL, NULL, &msgid );
  
  	ldap_pvt_thread_mutex_lock( &li->li_counter_mutex );
  	ldap_pvt_mp_add( li->li_ops_completed[ SLAP_OP_BIND ], 1 );
  	ldap_pvt_thread_mutex_unlock( &li->li_counter_mutex );
  
  	if ( rs->sr_err == LDAP_SERVER_DOWN ) {
  		if ( retries != LDAP_BACK_RETRY_NEVER ) {
  			if ( dolock ) {
  				ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  			}
  
  			assert( lc->lc_refcnt > 0 );
  			if ( lc->lc_refcnt == 1 ) {
  				ldap_unbind_ext( lc->lc_ld, NULL, NULL );
  				lc->lc_ld = NULL;
  
  				/* lc here must be the regular lc, reset and ready for init */
  				rs->sr_err = ldap_back_prepare_conn( lc, op, rs, sendok );
  				if ( rs->sr_err != LDAP_SUCCESS ) {
  					sendok &= ~LDAP_BACK_SENDERR;
  					lc->lc_refcnt = 0;
  				}
  			}
  
  			if ( dolock ) {
  				ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  			}
  
  			if ( rs->sr_err == LDAP_SUCCESS ) {
  				if ( retries > 0 ) {
  					retries--;
  				}
  				goto retry;
  			}
  		}
  
  		assert( lc->lc_refcnt == 1 );
  		lc->lc_refcnt = 0;
  		ldap_back_freeconn( li, lc, dolock );
  		*lcp = NULL;
  		rs->sr_err = slap_map_api2result( rs );
  
  		if ( LDAP_BACK_QUARANTINE( li ) ) {
  			ldap_back_quarantine( op, rs );
  		}
  
  		if ( rs->sr_err != LDAP_SUCCESS &&
  			( sendok & LDAP_BACK_SENDERR ) )
  		{
  			if ( op->o_callback == &cb )
  				op->o_callback = cb.sc_next;
  			op->o_tag = o_tag;
  			rs->sr_text = "Proxy can't contact remote server";
  			send_ldap_result( op, rs );
  		}
  
  		rc = 0;
  		goto func_leave;
  	}
  
  	rc = ldap_back_op_result( lc, op, rs, msgid,
  		-1, ( sendok | LDAP_BACK_BINDING ) );
  	if ( rc == LDAP_SUCCESS ) {
  		LDAP_BACK_CONN_ISBOUND_SET( lc );
  	}
  
  done:;
  	LDAP_BACK_CONN_BINDING_CLEAR( lc );
  	rc = LDAP_BACK_CONN_ISBOUND( lc );
  	if ( !rc ) {
  		ldap_back_release_conn_lock( li, lcp, dolock );
  
  	} else if ( LDAP_BACK_SAVECRED( li ) ) {
  		ldap_set_rebind_proc( lc->lc_ld, li->li_rebind_f, lc );
  	}
  
  func_leave:;
  	if ( op->o_callback == &cb )
  		op->o_callback = cb.sc_next;
  	op->o_tag = o_tag;
  
  	return rc;
  }
  
  /*
   * ldap_back_dobind
   *
   * Note: dolock indicates whether li->li_conninfo.lai_mutex must be locked or not
   */
  int
  ldap_back_dobind( ldapconn_t **lcp, Operation *op, SlapReply *rs, ldap_back_send_t sendok )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	return ldap_back_dobind_int( lcp, op, rs,
  		( sendok | LDAP_BACK_GETCONN ), li->li_nretries, 1 );
  }
  
  /*
   * ldap_back_default_rebind
   *
   * This is a callback used for chasing referrals using the same
   * credentials as the original user on this session.
   */
  int 
  ldap_back_default_rebind( LDAP *ld, LDAP_CONST char *url, ber_tag_t request,
  	ber_int_t msgid, void *params )
  {
  	ldapconn_t	*lc = (ldapconn_t *)params;
  
  #ifdef HAVE_TLS
  	/* ... otherwise we couldn't get here */
  	assert( lc != NULL );
  
  	if ( !ldap_tls_inplace( ld ) ) {
  		int		is_tls = LDAP_BACK_CONN_ISTLS( lc ),
  				rc;
  		const char	*text = NULL;
  
  		rc = ldap_back_start_tls( ld, 0, &is_tls, url, lc->lc_flags,
  			LDAP_BACK_RETRY_DEFAULT, &text );
  		if ( rc != LDAP_SUCCESS ) {
  			return rc;
  		}
  	}
  #endif /* HAVE_TLS */
  
  	/* FIXME: add checks on the URL/identity? */
  	/* TODO: would like to count this bind operation for monitoring
  	 * too, but where do we get the ldapinfo_t? */
  
  	return ldap_sasl_bind_s( ld,
  			BER_BVISNULL( &lc->lc_cred ) ? "" : lc->lc_bound_ndn.bv_val,
  			LDAP_SASL_SIMPLE, &lc->lc_cred, NULL, NULL, NULL );
  }
  
  /*
   * ldap_back_default_urllist
   */
  int 
  ldap_back_default_urllist(
  	LDAP		*ld,
  	LDAPURLDesc	**urllist,
  	LDAPURLDesc	**url,
  	void		*params )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)params;
  	LDAPURLDesc	**urltail;
  
  	if ( urllist == url ) {
  		return LDAP_SUCCESS;
  	}
  
  	for ( urltail = &(*url)->lud_next; *urltail; urltail = &(*urltail)->lud_next )
  		/* count */ ;
  
  	*urltail = *urllist;
  	*urllist = *url;
  	*url = NULL;
  
  	if ( !li->li_uri_mutex_do_not_lock ) {
  		ldap_pvt_thread_mutex_lock( &li->li_uri_mutex );
  	}
  
  	if ( li->li_uri ) {
  		ch_free( li->li_uri );
  	}
  
  	ldap_get_option( ld, LDAP_OPT_URI, (void *)&li->li_uri );
  
  	if ( !li->li_uri_mutex_do_not_lock ) {
  		ldap_pvt_thread_mutex_unlock( &li->li_uri_mutex );
  	}
  
  	return LDAP_SUCCESS;
  }
  
  int
  ldap_back_cancel(
  		ldapconn_t		*lc,
  		Operation		*op,
  		SlapReply		*rs,
  		ber_int_t		msgid,
  		ldap_back_send_t	sendok )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	/* default behavior */
  	if ( LDAP_BACK_ABANDON( li ) ) {
  		return ldap_abandon_ext( lc->lc_ld, msgid, NULL, NULL );
  	}
  
  	if ( LDAP_BACK_IGNORE( li ) ) {
  		return ldap_pvt_discard( lc->lc_ld, msgid );
  	}
  
  	if ( LDAP_BACK_CANCEL( li ) ) {
  		/* FIXME: asynchronous? */
  		return ldap_cancel_s( lc->lc_ld, msgid, NULL, NULL );
  	}
  
  	assert( 0 );
  
  	return LDAP_OTHER;
  }
  
  int
  ldap_back_op_result(
  		ldapconn_t		*lc,
  		Operation		*op,
  		SlapReply		*rs,
  		ber_int_t		msgid,
  		time_t			timeout,
  		ldap_back_send_t	sendok )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	char		*match = NULL;
  	char		*text = NULL;
  	char		**refs = NULL;
  	LDAPControl	**ctrls = NULL;
  
  	rs->sr_text = NULL;
  	rs->sr_matched = NULL;
  	rs->sr_ref = NULL;
  	rs->sr_ctrls = NULL;
  
  	/* if the error recorded in the reply corresponds
  	 * to a successful state, get the error from the
  	 * remote server response */
  	if ( LDAP_ERR_OK( rs->sr_err ) ) {
  		int		rc;
  		struct timeval	tv;
  		LDAPMessage	*res = NULL;
  		time_t		stoptime = (time_t)(-1);
  		int		timeout_err = op->o_protocol >= LDAP_VERSION3 ?
  					LDAP_ADMINLIMIT_EXCEEDED : LDAP_OTHER;
  		const char	*timeout_text = "Operation timed out";
  
  		/* if timeout is not specified, compute and use
  		 * the one specific to the ongoing operation */
  		if ( timeout == (time_t)(-1) ) {
  			slap_op_t	opidx = slap_req2op( op->o_tag );
  
  			if ( opidx == SLAP_OP_SEARCH ) {
  				if ( op->ors_tlimit <= 0 ) {
  					timeout = 0;
  
  				} else {
  					timeout = op->ors_tlimit;
  					timeout_err = LDAP_TIMELIMIT_EXCEEDED;
  					timeout_text = NULL;
  				}
  
  			} else {
  				timeout = li->li_timeout[ opidx ];
  			}
  		}
  
  		/* better than nothing :) */
  		if ( timeout == 0 ) {
  			if ( li->li_idle_timeout ) {
  				timeout = li->li_idle_timeout;
  
  			} else if ( li->li_conn_ttl ) {
  				timeout = li->li_conn_ttl;
  			}
  		}
  
  		if ( timeout ) {
  			stoptime = op->o_time + timeout;
  		}
  
  		LDAP_BACK_TV_SET( &tv );
  
  retry:;
  		/* if result parsing fails, note the failure reason */
  		rc = ldap_result( lc->lc_ld, msgid, LDAP_MSG_ALL, &tv, &res );
  		switch ( rc ) {
  		case 0:
  			if ( timeout && slap_get_time() > stoptime ) {
  				if ( sendok & LDAP_BACK_BINDING ) {
  					ldap_unbind_ext( lc->lc_ld, NULL, NULL );
  					lc->lc_ld = NULL;
  
  					/* let it be used, but taint/delete it so that 
  					 * no-one else can look it up any further */
  					ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  					ldap_back_print_conntree( li, ">>> ldap_back_getconn(timeout)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  
  					(void)ldap_back_conn_delete( li, lc );
  					LDAP_BACK_CONN_TAINTED_SET( lc );
  
  #if LDAP_BACK_PRINT_CONNTREE > 0
  					ldap_back_print_conntree( li, "<<< ldap_back_getconn(timeout)" );
  #endif /* LDAP_BACK_PRINT_CONNTREE */
  					ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  
  				} else {
  					(void)ldap_back_cancel( lc, op, rs, msgid, sendok );
  				}
  				rs->sr_err = timeout_err;
  				rs->sr_text = timeout_text;
  				break;
  			}
  
  			/* timeout == 0 */
  			LDAP_BACK_TV_SET( &tv );
  			ldap_pvt_thread_yield();
  			goto retry;
  
  		case -1:
  			ldap_get_option( lc->lc_ld, LDAP_OPT_ERROR_NUMBER,
  					&rs->sr_err );
  			break;
  
  
  		/* otherwise get the result; if it is not
  		 * LDAP_SUCCESS, record it in the reply
  		 * structure (this includes 
  		 * LDAP_COMPARE_{TRUE|FALSE}) */
  		default:
  			/* only touch when activity actually took place... */
  			if ( li->li_idle_timeout && lc ) {
  				lc->lc_time = op->o_time;
  			}
  
  			rc = ldap_parse_result( lc->lc_ld, res, &rs->sr_err,
  					&match, &text, &refs, &ctrls, 1 );
  			if ( rc == LDAP_SUCCESS ) {
  				rs->sr_text = text;
  			} else {
  				rs->sr_err = rc;
  			}
  			rs->sr_err = slap_map_api2result( rs );
  
  			/* RFC 4511: referrals can only appear
  			 * if result code is LDAP_REFERRAL */
  			if ( refs != NULL
  				&& refs[ 0 ] != NULL
  				&& refs[ 0 ][ 0 ] != '\0' )
  			{
  				if ( rs->sr_err != LDAP_REFERRAL ) {
  					Debug( LDAP_DEBUG_ANY,
  						"%s ldap_back_op_result: "
  						"got referrals with err=%d\n",
  						op->o_log_prefix,
  						rs->sr_err, 0 );
  
  				} else {
  					int	i;
  
  					for ( i = 0; refs[ i ] != NULL; i++ )
  						/* count */ ;
  					rs->sr_ref = op->o_tmpalloc( sizeof( struct berval ) * ( i + 1 ),
  						op->o_tmpmemctx );
  					for ( i = 0; refs[ i ] != NULL; i++ ) {
  						ber_str2bv( refs[ i ], 0, 0, &rs->sr_ref[ i ] );
  					}
  					BER_BVZERO( &rs->sr_ref[ i ] );
  				}
  
  			} else if ( rs->sr_err == LDAP_REFERRAL ) {
  				Debug( LDAP_DEBUG_ANY,
  					"%s ldap_back_op_result: "
  					"got err=%d with null "
  					"or empty referrals\n",
  					op->o_log_prefix,
  					rs->sr_err, 0 );
  
  				rs->sr_err = LDAP_NO_SUCH_OBJECT;
  			}
  
  			if ( ctrls != NULL ) {
  				rs->sr_ctrls = ctrls;
  			}
  		}
  	}
  
  	/* if the error in the reply structure is not
  	 * LDAP_SUCCESS, try to map it from client 
  	 * to server error */
  	if ( !LDAP_ERR_OK( rs->sr_err ) ) {
  		rs->sr_err = slap_map_api2result( rs );
  
  		/* internal ops ( op->o_conn == NULL ) 
  		 * must not reply to client */
  		if ( op->o_conn && !op->o_do_not_cache && match ) {
  
  			/* record the (massaged) matched
  			 * DN into the reply structure */
  			rs->sr_matched = match;
  		}
  	}
  
  	if ( rs->sr_err == LDAP_UNAVAILABLE ) {
  		if ( !( sendok & LDAP_BACK_RETRYING ) ) {
  			if ( LDAP_BACK_QUARANTINE( li ) ) {
  				ldap_back_quarantine( op, rs );
  			}
  			if ( op->o_conn && ( sendok & LDAP_BACK_SENDERR ) ) {
  				if ( rs->sr_text == NULL ) rs->sr_text = "Proxy operation retry failed";
  				send_ldap_result( op, rs );
  			}
  		}
  
  	} else if ( op->o_conn &&
  		( ( ( sendok & LDAP_BACK_SENDOK ) && LDAP_ERR_OK( rs->sr_err ) )
  			|| ( ( sendok & LDAP_BACK_SENDERR ) && !LDAP_ERR_OK( rs->sr_err ) ) ) )
  	{
  		send_ldap_result( op, rs );
  	}
  
  	if ( text ) {
  		ldap_memfree( text );
  	}
  	rs->sr_text = NULL;
  
  	/* there can't be refs with a (successful) bind */
  	if ( rs->sr_ref ) {
  		op->o_tmpfree( rs->sr_ref, op->o_tmpmemctx );
  		rs->sr_ref = NULL;
  	}
  
  	if ( refs ) {
  		ber_memvfree( (void **)refs );
  	}
  
  	/* match should not be possible with a successful bind */
  	if ( match ) {
  		if ( rs->sr_matched != match ) {
  			free( (char *)rs->sr_matched );
  		}
  		rs->sr_matched = NULL;
  		ldap_memfree( match );
  	}
  
  	if ( ctrls != NULL ) {
  		if ( op->o_tag == LDAP_REQ_BIND && rs->sr_err == LDAP_SUCCESS ) {
  			int i;
  
  			for ( i = 0; ctrls[i] != NULL; i++ );
  
  			rs->sr_ctrls = op->o_tmpalloc( sizeof( LDAPControl * )*( i + 1 ),
  				op->o_tmpmemctx );
  			for ( i = 0; ctrls[ i ] != NULL; i++ ) {
  				char *ptr;
  				ber_len_t oidlen = strlen( ctrls[i]->ldctl_oid );
  				ber_len_t size = sizeof( LDAPControl )
  					+ oidlen + 1
  					+ ctrls[i]->ldctl_value.bv_len + 1;
  	
  				rs->sr_ctrls[ i ] = op->o_tmpalloc( size, op->o_tmpmemctx );
  				rs->sr_ctrls[ i ]->ldctl_oid = (char *)&rs->sr_ctrls[ i ][ 1 ];
  				lutil_strcopy( rs->sr_ctrls[ i ]->ldctl_oid, ctrls[i]->ldctl_oid );
  				rs->sr_ctrls[ i ]->ldctl_value.bv_val
  						= (char *)&rs->sr_ctrls[ i ]->ldctl_oid[oidlen + 1];
  				rs->sr_ctrls[ i ]->ldctl_value.bv_len
  					= ctrls[i]->ldctl_value.bv_len;
  				ptr = lutil_memcopy( rs->sr_ctrls[ i ]->ldctl_value.bv_val,
  					ctrls[i]->ldctl_value.bv_val, ctrls[i]->ldctl_value.bv_len );
  				*ptr = '\0';
  			}
  			rs->sr_ctrls[ i ] = NULL;
  			rs->sr_flags |= REP_CTRLS_MUSTBEFREED;
  
  		} else {
  			assert( rs->sr_ctrls != NULL );
  			rs->sr_ctrls = NULL;
  		}
  
  		ldap_controls_free( ctrls );
  	}
  
  	return( LDAP_ERR_OK( rs->sr_err ) ? LDAP_SUCCESS : rs->sr_err );
  }
  
  /* return true if bound, false if failed */
  int
  ldap_back_retry( ldapconn_t **lcp, Operation *op, SlapReply *rs, ldap_back_send_t sendok )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  	int		rc = 0;
  
  	assert( lcp != NULL );
  	assert( *lcp != NULL );
  
  	ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
  
  	if ( (*lcp)->lc_refcnt == 1 ) {
  		int binding = LDAP_BACK_CONN_BINDING( *lcp );
  
  		ldap_pvt_thread_mutex_lock( &li->li_uri_mutex );
  		Debug( LDAP_DEBUG_ANY,
  			"%s ldap_back_retry: retrying URI=\"%s\" DN=\"%s\"\n",
  			op->o_log_prefix, li->li_uri,
  			BER_BVISNULL( &(*lcp)->lc_bound_ndn ) ?
  				"" : (*lcp)->lc_bound_ndn.bv_val );
  		ldap_pvt_thread_mutex_unlock( &li->li_uri_mutex );
  
  		ldap_unbind_ext( (*lcp)->lc_ld, NULL, NULL );
  		(*lcp)->lc_ld = NULL;
  		LDAP_BACK_CONN_ISBOUND_CLEAR( (*lcp) );
  
  		/* lc here must be the regular lc, reset and ready for init */
  		rc = ldap_back_prepare_conn( *lcp, op, rs, sendok );
  		if ( rc != LDAP_SUCCESS ) {
  			/* freeit, because lc_refcnt == 1 */
  			(*lcp)->lc_refcnt = 0;
  			(void)ldap_back_freeconn( li, *lcp, 0 );
  			*lcp = NULL;
  			rc = 0;
  
  		} else if ( ( sendok & LDAP_BACK_BINDING ) ) {
  			if ( binding ) {
  				LDAP_BACK_CONN_BINDING_SET( *lcp );
  			}
  			rc = 1;
  
  		} else {
  			rc = ldap_back_dobind_int( lcp, op, rs, sendok, 0, 0 );
  			if ( rc == 0 && *lcp != NULL ) {
  				/* freeit, because lc_refcnt == 1 */
  				(*lcp)->lc_refcnt = 0;
  				LDAP_BACK_CONN_TAINTED_SET( *lcp );
  				(void)ldap_back_freeconn( li, *lcp, 0 );
  				*lcp = NULL;
  			}
  		}
  
  	} else {
  		Debug( LDAP_DEBUG_TRACE,
  			"ldap_back_retry: conn %p refcnt=%u unable to retry.\n",
  			(void *)(*lcp), (*lcp)->lc_refcnt, 0 );
  
  		LDAP_BACK_CONN_TAINTED_SET( *lcp );
  		ldap_back_release_conn_lock( li, lcp, 0 );
  		assert( *lcp == NULL );
  
  		if ( sendok & LDAP_BACK_SENDERR ) {
  			rs->sr_err = LDAP_UNAVAILABLE;
  			rs->sr_text = "Unable to retry";
  			send_ldap_result( op, rs );
  		}
  	}
  
  	ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
  
  	return rc;
  }
  
  static int
  ldap_back_is_proxy_authz( Operation *op, SlapReply *rs, ldap_back_send_t sendok,
  	struct berval *binddn, struct berval *bindcred )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  	struct berval	ndn;
  	int		dobind = 0;
  
  	if ( op->o_conn == NULL || op->o_do_not_cache ) {
  		goto done;
  	}
  
  	/* don't proxyAuthz if protocol is not LDAPv3 */
  	switch ( li->li_version ) {
  	case LDAP_VERSION3:
  		break;
  
  	case 0:
  		if ( op->o_protocol == 0 || op->o_protocol == LDAP_VERSION3 ) {
  			break;
  		}
  		/* fall thru */
  
  	default:
  		rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
  		if ( sendok & LDAP_BACK_SENDERR ) {
  			send_ldap_result( op, rs );
  			dobind = -1;
  		}
  		goto done;
  	}
  
  	/* safe default */
  	*binddn = slap_empty_bv;
  	*bindcred = slap_empty_bv;
  
  	if ( !BER_BVISNULL( &op->o_conn->c_ndn ) ) {
  		ndn = op->o_conn->c_ndn;
  
  	} else {
  		ndn = op->o_ndn;
  	}
  
  	if ( !( li->li_idassert_flags & LDAP_BACK_AUTH_OVERRIDE )) {
  		if ( op->o_tag == LDAP_REQ_BIND ) {
  			if ( !BER_BVISEMPTY( &ndn )) {
  				dobind = 0;
  				goto done;
  			}
  		} else if ( SLAP_IS_AUTHZ_BACKEND( op )) {
  			dobind = 0;
  			goto done;
  		}
  	}
  
  	switch ( li->li_idassert_mode ) {
  	case LDAP_BACK_IDASSERT_LEGACY:
  		if ( !BER_BVISNULL( &ndn ) && !BER_BVISEMPTY( &ndn ) ) {
  			if ( !BER_BVISNULL( &li->li_idassert_authcDN ) && !BER_BVISEMPTY( &li->li_idassert_authcDN ) )
  			{
  				*binddn = li->li_idassert_authcDN;
  				*bindcred = li->li_idassert_passwd;
  				dobind = 1;
  			}
  		}
  		break;
  
  	default:
  		/* NOTE: rootdn can always idassert */
  		if ( BER_BVISNULL( &ndn )
  			&& li->li_idassert_authz == NULL
  			&& !( li->li_idassert_flags & LDAP_BACK_AUTH_AUTHZ_ALL ) )
  		{
  			if ( li->li_idassert_flags & LDAP_BACK_AUTH_PRESCRIPTIVE ) {
  				rs->sr_err = LDAP_INAPPROPRIATE_AUTH;
  				if ( sendok & LDAP_BACK_SENDERR ) {
  					send_ldap_result( op, rs );
  					dobind = -1;
  				}
  
  			} else {
  				rs->sr_err = LDAP_SUCCESS;
  				*binddn = slap_empty_bv;
  				*bindcred = slap_empty_bv;
  				break;
  			}
  
  			goto done;
  
  		} else if ( !be_isroot( op ) ) {
  			if ( li->li_idassert_passthru ) {
  				struct berval authcDN;
  
  				if ( BER_BVISNULL( &ndn ) ) {
  					authcDN = slap_empty_bv;
  
  				} else {
  					authcDN = ndn;
  				}	
  				rs->sr_err = slap_sasl_matches( op, li->li_idassert_passthru,
  						&authcDN, &authcDN );
  				if ( rs->sr_err == LDAP_SUCCESS ) {
  					dobind = 0;
  					break;
  				}
  			}
  
  			if ( li->li_idassert_authz ) {
  				struct berval authcDN;
  
  				if ( BER_BVISNULL( &ndn ) ) {
  					authcDN = slap_empty_bv;
  
  				} else {
  					authcDN = ndn;
  				}	
  				rs->sr_err = slap_sasl_matches( op, li->li_idassert_authz,
  						&authcDN, &authcDN );
  				if ( rs->sr_err != LDAP_SUCCESS ) {
  					if ( li->li_idassert_flags & LDAP_BACK_AUTH_PRESCRIPTIVE ) {
  						if ( sendok & LDAP_BACK_SENDERR ) {
  							send_ldap_result( op, rs );
  							dobind = -1;
  						}
  
  					} else {
  						rs->sr_err = LDAP_SUCCESS;
  						*binddn = slap_empty_bv;
  						*bindcred = slap_empty_bv;
  						break;
  					}
  
  					goto done;
  				}
  			}
  		}
  
  		*binddn = li->li_idassert_authcDN;
  		*bindcred = li->li_idassert_passwd;
  		dobind = 1;
  		break;
  	}
  
  done:;
  	return dobind;
  }
  
  static int
  ldap_back_proxy_authz_bind(
  	ldapconn_t		*lc,
  	Operation		*op,
  	SlapReply		*rs,
  	ldap_back_send_t	sendok,
  	struct berval		*binddn,
  	struct berval		*bindcred )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  	struct berval	ndn;
  	int		msgid;
  	int		rc;
  
  	if ( !BER_BVISNULL( &op->o_conn->c_ndn ) ) {
  		ndn = op->o_conn->c_ndn;
  
  	} else {
  		ndn = op->o_ndn;
  	}
  
  	if ( li->li_idassert_authmethod == LDAP_AUTH_SASL ) {
  #ifdef HAVE_CYRUS_SASL
  		void		*defaults = NULL;
  		struct berval	authzID = BER_BVNULL;
  		int		freeauthz = 0;
  		LDAPControl **ctrlsp = NULL;
  		LDAPMessage *result = NULL;
  		const char *rmech = NULL;
  		const char *save_text = rs->sr_text;
  
  #ifdef SLAP_AUTH_DN
  		LDAPControl ctrl, *ctrls[2];
  		int msgid;
  #endif /* SLAP_AUTH_DN */
  
  		/* if SASL supports native authz, prepare for it */
  		if ( ( !op->o_do_not_cache || !op->o_is_auth_check ) &&
  				( li->li_idassert_flags & LDAP_BACK_AUTH_NATIVE_AUTHZ ) )
  		{
  			switch ( li->li_idassert_mode ) {
  			case LDAP_BACK_IDASSERT_OTHERID:
  			case LDAP_BACK_IDASSERT_OTHERDN:
  				authzID = li->li_idassert_authzID;
  				break;
  
  			case LDAP_BACK_IDASSERT_ANONYMOUS:
  				BER_BVSTR( &authzID, "dn:" );
  				break;
  
  			case LDAP_BACK_IDASSERT_SELF:
  				if ( BER_BVISNULL( &ndn ) ) {
  					/* connection is not authc'd, so don't idassert */
  					BER_BVSTR( &authzID, "dn:" );
  					break;
  				}
  				authzID.bv_len = STRLENOF( "dn:" ) + ndn.bv_len;
  				authzID.bv_val = slap_sl_malloc( authzID.bv_len + 1, op->o_tmpmemctx );
  				AC_MEMCPY( authzID.bv_val, "dn:", STRLENOF( "dn:" ) );
  				AC_MEMCPY( authzID.bv_val + STRLENOF( "dn:" ),
  						ndn.bv_val, ndn.bv_len + 1 );
  				freeauthz = 1;
  				break;
  
  			default:
  				break;
  			}
  		}
  
  		if ( li->li_idassert_secprops != NULL ) {
  			rs->sr_err = ldap_set_option( lc->lc_ld,
  				LDAP_OPT_X_SASL_SECPROPS,
  				(void *)li->li_idassert_secprops );
  
  			if ( rs->sr_err != LDAP_OPT_SUCCESS ) {
  				rs->sr_err = LDAP_OTHER;
  				if ( sendok & LDAP_BACK_SENDERR ) {
  					send_ldap_result( op, rs );
  				}
  				LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  				goto done;
  			}
  		}
  
  		defaults = lutil_sasl_defaults( lc->lc_ld,
  				li->li_idassert_sasl_mech.bv_val,
  				li->li_idassert_sasl_realm.bv_val,
  				li->li_idassert_authcID.bv_val,
  				li->li_idassert_passwd.bv_val,
  				authzID.bv_val );
  		if ( defaults == NULL ) {
  			rs->sr_err = LDAP_OTHER;
  			LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  			if ( sendok & LDAP_BACK_SENDERR ) {
  				send_ldap_result( op, rs );
  			}
  			goto done;
  		}
  
  #ifdef SLAP_AUTH_DN
  		if ( li->li_idassert_flags & LDAP_BACK_AUTH_DN_AUTHZID ) {
  			assert( BER_BVISNULL( binddn ) );
  
  			ctrl.ldctl_oid = LDAP_CONTROL_AUTHZID_REQUEST;
  			ctrl.ldctl_iscritical = 0;
  			BER_BVZERO( &ctrl.ldctl_value );
  			ctrls[0] = &ctrl;
  			ctrls[1] = NULL;
  			ctrlsp = ctrls;
  		}
  #endif /* SLAP_AUTH_DN */
  
  		do {
  			rs->sr_err = ldap_sasl_interactive_bind( lc->lc_ld, binddn->bv_val,
  				li->li_idassert_sasl_mech.bv_val, 
  				ctrlsp, NULL, LDAP_SASL_QUIET, lutil_sasl_interact, defaults,
  				result, &rmech, &msgid );
  
  			if ( rs->sr_err != LDAP_SASL_BIND_IN_PROGRESS )
  				break;
  
  			ldap_msgfree( result );
  
  			if ( ldap_result( lc->lc_ld, msgid, LDAP_MSG_ALL, NULL, &result ) == -1 || !result ) {
  				ldap_get_option( lc->lc_ld, LDAP_OPT_RESULT_CODE, (void*)&rs->sr_err );
  				ldap_get_option( lc->lc_ld, LDAP_OPT_DIAGNOSTIC_MESSAGE, (void*)&rs->sr_text );
  				break;
  			}
  		} while ( rs->sr_err == LDAP_SASL_BIND_IN_PROGRESS );
  
  		ldap_pvt_thread_mutex_lock( &li->li_counter_mutex );
  		ldap_pvt_mp_add( li->li_ops_completed[ SLAP_OP_BIND ], 1 );
  		ldap_pvt_thread_mutex_unlock( &li->li_counter_mutex );
  
  		switch ( rs->sr_err ) {
  		case LDAP_SUCCESS:
  #ifdef SLAP_AUTH_DN
  			/* FIXME: right now, the only reason to check
  			 * response controls is RFC 3829 authzid */
  			if ( li->li_idassert_flags & LDAP_BACK_AUTH_DN_AUTHZID ) {
  				ctrlsp = NULL;
  				rc = ldap_parse_result( lc->lc_ld, result, NULL, NULL, NULL, NULL,
  					&ctrlsp, 0 );
  				if ( rc == LDAP_SUCCESS && ctrlsp ) {
  					LDAPControl *ctrl;
  		
  					ctrl = ldap_control_find( LDAP_CONTROL_AUTHZID_RESPONSE,
  						ctrlsp, NULL );
  					if ( ctrl ) {
  						Debug( LDAP_DEBUG_TRACE, "%s: ldap_back_proxy_authz_bind: authzID=\"%s\" (authzid)\n",
  							op->o_log_prefix, ctrl->ldctl_value.bv_val, 0 );
  						if ( ctrl->ldctl_value.bv_len > STRLENOF("dn:") &&
  							strncasecmp( ctrl->ldctl_value.bv_val, "dn:", STRLENOF("dn:") ) == 0 )
  						{
  							struct berval bv;
  							bv.bv_val = &ctrl->ldctl_value.bv_val[STRLENOF("dn:")];
  							bv.bv_len = ctrl->ldctl_value.bv_len - STRLENOF("dn:");
  							ber_bvreplace( &lc->lc_bound_ndn, &bv );
  						}
  					}
  				}
  
  				ldap_controls_free( ctrlsp );
  
  			} else if ( li->li_idassert_flags & LDAP_BACK_AUTH_DN_WHOAMI ) {
  				struct berval *val = NULL;
  				rc = ldap_whoami_s( lc->lc_ld, &val, NULL, NULL );
  				if ( rc == LDAP_SUCCESS && val != NULL ) {
  					Debug( LDAP_DEBUG_TRACE, "%s: ldap_back_proxy_authz_bind: authzID=\"%s\" (whoami)\n",
  						op->o_log_prefix, val->bv_val, 0 );
  					if ( val->bv_len > STRLENOF("dn:") &&
  						strncasecmp( val->bv_val, "dn:", STRLENOF("dn:") ) == 0 )
  					{
  						struct berval bv;
  						bv.bv_val = &val->bv_val[STRLENOF("dn:")];
  						bv.bv_len = val->bv_len - STRLENOF("dn:");
  						ber_bvreplace( &lc->lc_bound_ndn, &bv );
  					}
  					ber_bvfree( val );
  				}
  			}
  
  			if ( ( li->li_idassert_flags & LDAP_BACK_AUTH_DN_MASK ) &&
  				BER_BVISNULL( &lc->lc_bound_ndn ) )
  			{
  				/* all in all, we only need it to be non-null */
  				/* FIXME: should this be configurable? */
  				static struct berval bv = BER_BVC("cn=authzdn");
  				ber_bvreplace( &lc->lc_bound_ndn, &bv );
  			}
  #endif /* SLAP_AUTH_DN */
  			LDAP_BACK_CONN_ISBOUND_SET( lc );
  			break;
  
  		case LDAP_LOCAL_ERROR:
  			/* list client API error codes that require
  			 * to taint the connection */
  			/* FIXME: should actually retry? */
  			LDAP_BACK_CONN_TAINTED_SET( lc );
  
  			/* fallthru */
  
  		default:
  			LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  			rs->sr_err = slap_map_api2result( rs );
  			if ( sendok & LDAP_BACK_SENDERR ) {
  				send_ldap_result( op, rs );
  			}
  			break;
  		}
  
  		if ( save_text != rs->sr_text ) {
  			ldap_memfree( (char *)rs->sr_text );
  			rs->sr_text = save_text;
  		}
  
  		ldap_msgfree( result );
  
  		lutil_sasl_freedefs( defaults );
  		if ( freeauthz ) {
  			slap_sl_free( authzID.bv_val, op->o_tmpmemctx );
  		}
  
  		goto done;
  #endif /* HAVE_CYRUS_SASL */
  	}
  
  	switch ( li->li_idassert_authmethod ) {
  	case LDAP_AUTH_NONE:
  		/* FIXME: do we really need this? */
  		BER_BVSTR( binddn, "" );
  		BER_BVSTR( bindcred, "" );
  		/* fallthru */
  
  	case LDAP_AUTH_SIMPLE:
  		rs->sr_err = ldap_sasl_bind( lc->lc_ld,
  				binddn->bv_val, LDAP_SASL_SIMPLE,
  				bindcred, NULL, NULL, &msgid );
  		rc = ldap_back_op_result( lc, op, rs, msgid,
  			-1, ( sendok | LDAP_BACK_BINDING ) );
  
  		ldap_pvt_thread_mutex_lock( &li->li_counter_mutex );
  		ldap_pvt_mp_add( li->li_ops_completed[ SLAP_OP_BIND ], 1 );
  		ldap_pvt_thread_mutex_unlock( &li->li_counter_mutex );
  		break;
  
  	default:
  		/* unsupported! */
  		LDAP_BACK_CONN_ISBOUND_CLEAR( lc );
  		rs->sr_err = LDAP_AUTH_METHOD_NOT_SUPPORTED;
  		if ( sendok & LDAP_BACK_SENDERR ) {
  			send_ldap_result( op, rs );
  		}
  		goto done;
  	}
  
  	if ( rc == LDAP_SUCCESS ) {
  		/* set rebind stuff in case of successful proxyAuthz bind,
  		 * so that referral chasing is attempted using the right
  		 * identity */
  		LDAP_BACK_CONN_ISBOUND_SET( lc );
  		if ( !BER_BVISNULL( binddn ) ) {
  			ber_bvreplace( &lc->lc_bound_ndn, binddn );
  		}
  
  		if ( !BER_BVISNULL( &lc->lc_cred ) ) {
  			memset( lc->lc_cred.bv_val, 0,
  					lc->lc_cred.bv_len );
  		}
  
  		if ( LDAP_BACK_SAVECRED( li ) ) {
  			if ( !BER_BVISNULL( bindcred ) ) {
  				ber_bvreplace( &lc->lc_cred, bindcred );
  				ldap_set_rebind_proc( lc->lc_ld, li->li_rebind_f, lc );
  			}
  
  		} else {
  			lc->lc_cred.bv_len = 0;
  		}
  	}
  
  done:;
  	return LDAP_BACK_CONN_ISBOUND( lc );
  }
  
  /*
   * ldap_back_proxy_authz_ctrl() prepends a proxyAuthz control
   * to existing server-side controls if required; if not,
   * the existing server-side controls are placed in *pctrls.
   * The caller, after using the controls in client API 
   * operations, if ( *pctrls != op->o_ctrls ), should
   * free( (*pctrls)[ 0 ] ) and free( *pctrls ).
   * The function returns success if the control could
   * be added if required, or if it did nothing; in the future,
   * it might return some error if it failed.
   * 
   * if no bind took place yet, but the connection is bound
   * and the "proxyauthzdn" is set, then bind as "proxyauthzdn" 
   * and explicitly add proxyAuthz the control to every operation
   * with the dn bound to the connection as control value.
   *
   * If no server-side controls are defined for the operation,
   * simply add the proxyAuthz control; otherwise, if the
   * proxyAuthz control is not already set, add it as
   * the first one
   *
   * FIXME: is controls order significant for security?
   * ANSWER: controls ordering and interoperability
   * must be indicated by the specs of each control; if none
   * is specified, the order is irrelevant.
   */
  int
  ldap_back_proxy_authz_ctrl(
  		Operation	*op,
  		SlapReply	*rs,
  		struct berval	*bound_ndn,
  		int		version,
  		slap_idassert_t	*si,
  		LDAPControl	*ctrl )
  {
  	slap_idassert_mode_t	mode;
  	struct berval		assertedID,
  				ndn;
  	int			isroot = 0;
  
  	rs->sr_err = SLAP_CB_CONTINUE;
  
  	/* FIXME: SASL/EXTERNAL over ldapi:// doesn't honor the authcID,
  	 * but if it is not set this test fails.  We need a different
  	 * means to detect if idassert is enabled */
  	if ( ( BER_BVISNULL( &si->si_bc.sb_authcId ) || BER_BVISEMPTY( &si->si_bc.sb_authcId ) )
  		&& ( BER_BVISNULL( &si->si_bc.sb_binddn ) || BER_BVISEMPTY( &si->si_bc.sb_binddn ) )
  		&& BER_BVISNULL( &si->si_bc.sb_saslmech ) )
  	{
  		goto done;
  	}
  
  	if ( !op->o_conn || op->o_do_not_cache || ( isroot = be_isroot( op ) ) ) {
  		goto done;
  	}
  
  	if ( op->o_tag == LDAP_REQ_BIND ) {
  		ndn = op->o_req_ndn;
  
  	} else if ( !BER_BVISNULL( &op->o_conn->c_ndn ) ) {
  		ndn = op->o_conn->c_ndn;
  
  	} else {
  		ndn = op->o_ndn;
  	}
  
  	if ( si->si_mode == LDAP_BACK_IDASSERT_LEGACY ) {
  		if ( op->o_proxy_authz ) {
  			/*
  			 * FIXME: we do not want to perform proxyAuthz
  			 * on behalf of the client, because this would
  			 * be performed with "proxyauthzdn" privileges.
  			 *
  			 * This might actually be too strict, since
  			 * the "proxyauthzdn" authzTo, and each entry's
  			 * authzFrom attributes may be crafted
  			 * to avoid unwanted proxyAuthz to take place.
  			 */
  #if 0
  			rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
  			rs->sr_text = "proxyAuthz not allowed within namingContext";
  #endif
  			goto done;
  		}
  
  		if ( !BER_BVISNULL( bound_ndn ) ) {
  			goto done;
  		}
  
  		if ( BER_BVISNULL( &ndn ) ) {
  			goto done;
  		}
  
  		if ( BER_BVISNULL( &si->si_bc.sb_binddn ) ) {
  			goto done;
  		}
  
  	} else if ( si->si_bc.sb_method == LDAP_AUTH_SASL ) {
  		if ( ( si->si_flags & LDAP_BACK_AUTH_NATIVE_AUTHZ ) )
  		{
  			/* already asserted in SASL via native authz */
  			goto done;
  		}
  
  	} else if ( si->si_authz && !isroot ) {
  		int		rc;
  		struct berval authcDN;
  
  		if ( BER_BVISNULL( &ndn ) ) {
  			authcDN = slap_empty_bv;
  		} else {
  			authcDN = ndn;
  		}
  		rc = slap_sasl_matches( op, si->si_authz,
  				&authcDN, &authcDN );
  		if ( rc != LDAP_SUCCESS ) {
  			if ( si->si_flags & LDAP_BACK_AUTH_PRESCRIPTIVE ) {
  				/* ndn is not authorized
  				 * to use idassert */
  				rs->sr_err = rc;
  			}
  			goto done;
  		}
  	}
  
  	if ( op->o_proxy_authz ) {
  		/*
  		 * FIXME: we can:
  		 * 1) ignore the already set proxyAuthz control
  		 * 2) leave it in place, and don't set ours
  		 * 3) add both
  		 * 4) reject the operation
  		 *
  		 * option (4) is very drastic
  		 * option (3) will make the remote server reject
  		 * the operation, thus being equivalent to (4)
  		 * option (2) will likely break the idassert
  		 * assumptions, so we cannot accept it;
  		 * option (1) means that we are contradicting
  		 * the client's reques.
  		 *
  		 * I think (4) is the only correct choice.
  		 */
  		rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
  		rs->sr_text = "proxyAuthz not allowed within namingContext";
  	}
  
  	if ( op->o_is_auth_check ) {
  		mode = LDAP_BACK_IDASSERT_NOASSERT;
  
  	} else {
  		mode = si->si_mode;
  	}
  
  	switch ( mode ) {
  	case LDAP_BACK_IDASSERT_LEGACY:
  		/* original behavior:
  		 * assert the client's identity */
  	case LDAP_BACK_IDASSERT_SELF:
  		assertedID = ndn;
  		break;
  
  	case LDAP_BACK_IDASSERT_ANONYMOUS:
  		/* assert "anonymous" */
  		assertedID = slap_empty_bv;
  		break;
  
  	case LDAP_BACK_IDASSERT_NOASSERT:
  		/* don't assert; bind as proxyauthzdn */
  		goto done;
  
  	case LDAP_BACK_IDASSERT_OTHERID:
  	case LDAP_BACK_IDASSERT_OTHERDN:
  		/* assert idassert DN */
  		assertedID = si->si_bc.sb_authzId;
  		break;
  
  	default:
  		assert( 0 );
  	}
  
  	/* if we got here, "" is allowed to proxyAuthz */
  	if ( BER_BVISNULL( &assertedID ) ) {
  		assertedID = slap_empty_bv;
  	}
  
  	/* don't idassert the bound DN (ITS#4497) */
  	if ( dn_match( &assertedID, bound_ndn ) ) {
  		goto done;
  	}
  
  	ctrl->ldctl_oid = LDAP_CONTROL_PROXY_AUTHZ;
  	ctrl->ldctl_iscritical = ( ( si->si_flags & LDAP_BACK_AUTH_PROXYAUTHZ_CRITICAL ) == LDAP_BACK_AUTH_PROXYAUTHZ_CRITICAL );
  
  	switch ( si->si_mode ) {
  	/* already in u:ID or dn:DN form */
  	case LDAP_BACK_IDASSERT_OTHERID:
  	case LDAP_BACK_IDASSERT_OTHERDN:
  		ber_dupbv_x( &ctrl->ldctl_value, &assertedID, op->o_tmpmemctx );
  		rs->sr_err = LDAP_SUCCESS;
  		break;
  
  	/* needs the dn: prefix */
  	default:
  		ctrl->ldctl_value.bv_len = assertedID.bv_len + STRLENOF( "dn:" );
  		ctrl->ldctl_value.bv_val = op->o_tmpalloc( ctrl->ldctl_value.bv_len + 1,
  				op->o_tmpmemctx );
  		AC_MEMCPY( ctrl->ldctl_value.bv_val, "dn:", STRLENOF( "dn:" ) );
  		AC_MEMCPY( &ctrl->ldctl_value.bv_val[ STRLENOF( "dn:" ) ],
  				assertedID.bv_val, assertedID.bv_len + 1 );
  		rs->sr_err = LDAP_SUCCESS;
  		break;
  	}
  
  	/* Older versions of <draft-weltman-ldapv3-proxy> required
  	 * to encode the value of the authzID (and called it proxyDN);
  	 * this hack provides compatibility with those DSAs that
  	 * implement it this way */
  	if ( si->si_flags & LDAP_BACK_AUTH_OBSOLETE_ENCODING_WORKAROUND ) {
  		struct berval		authzID = ctrl->ldctl_value;
  		BerElementBuffer	berbuf;
  		BerElement		*ber = (BerElement *)&berbuf;
  		ber_tag_t		tag;
  
  		ber_init2( ber, 0, LBER_USE_DER );
  		ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );
  
  		tag = ber_printf( ber, "O", &authzID );
  		if ( tag == LBER_ERROR ) {
  			rs->sr_err = LDAP_OTHER;
  			goto free_ber;
  		}
  
  		if ( ber_flatten2( ber, &ctrl->ldctl_value, 1 ) == -1 ) {
  			rs->sr_err = LDAP_OTHER;
  			goto free_ber;
  		}
  
  		rs->sr_err = LDAP_SUCCESS;
  
  free_ber:;
  		op->o_tmpfree( authzID.bv_val, op->o_tmpmemctx );
  		ber_free_buf( ber );
  
  		if ( rs->sr_err != LDAP_SUCCESS ) {
  			goto done;
  		}
  
  	} else if ( si->si_flags & LDAP_BACK_AUTH_OBSOLETE_PROXY_AUTHZ ) {
  		struct berval		authzID = ctrl->ldctl_value,
  					tmp;
  		BerElementBuffer	berbuf;
  		BerElement		*ber = (BerElement *)&berbuf;
  		ber_tag_t		tag;
  
  		if ( strncasecmp( authzID.bv_val, "dn:", STRLENOF( "dn:" ) ) != 0 ) {
  			rs->sr_err = LDAP_PROTOCOL_ERROR;
  			goto done;
  		}
  
  		tmp = authzID;
  		tmp.bv_val += STRLENOF( "dn:" );
  		tmp.bv_len -= STRLENOF( "dn:" );
  
  		ber_init2( ber, 0, LBER_USE_DER );
  		ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );
  
  		/* apparently, Mozilla API encodes this
  		 * as "SEQUENCE { LDAPDN }" */
  		tag = ber_printf( ber, "{O}", &tmp );
  		if ( tag == LBER_ERROR ) {
  			rs->sr_err = LDAP_OTHER;
  			goto free_ber2;
  		}
  
  		if ( ber_flatten2( ber, &ctrl->ldctl_value, 1 ) == -1 ) {
  			rs->sr_err = LDAP_OTHER;
  			goto free_ber2;
  		}
  
  		ctrl->ldctl_oid = LDAP_CONTROL_OBSOLETE_PROXY_AUTHZ;
  		rs->sr_err = LDAP_SUCCESS;
  
  free_ber2:;
  		op->o_tmpfree( authzID.bv_val, op->o_tmpmemctx );
  		ber_free_buf( ber );
  
  		if ( rs->sr_err != LDAP_SUCCESS ) {
  			goto done;
  		}
  	}
  
  done:;
  
  	return rs->sr_err;
  }
  
  /*
   * Add controls;
   *
   * if any needs to be added, it is prepended to existing ones,
   * in a newly allocated array.  The companion function
   * ldap_back_controls_free() must be used to restore the original
   * status of op->o_ctrls.
   */
  int
  ldap_back_controls_add(
  		Operation	*op,
  		SlapReply	*rs,
  		ldapconn_t	*lc,
  		LDAPControl	***pctrls )
  {
  	ldapinfo_t	*li = (ldapinfo_t *)op->o_bd->be_private;
  
  	LDAPControl	**ctrls = NULL;
  	/* set to the maximum number of controls this backend can add */
  	LDAPControl	c[ 2 ] = { { 0 } };
  	int		n = 0, i, j1 = 0, j2 = 0;
  
  	*pctrls = NULL;
  
  	rs->sr_err = LDAP_SUCCESS;
  
  	/* don't add controls if protocol is not LDAPv3 */
  	switch ( li->li_version ) {
  	case LDAP_VERSION3:
  		break;
  
  	case 0:
  		if ( op->o_protocol == 0 || op->o_protocol == LDAP_VERSION3 ) {
  			break;
  		}
  		/* fall thru */
  
  	default:
  		goto done;
  	}
  
  	/* put controls that go __before__ existing ones here */
  
  	/* proxyAuthz for identity assertion */
  	switch ( ldap_back_proxy_authz_ctrl( op, rs, &lc->lc_bound_ndn,
  		li->li_version, &li->li_idassert, &c[ j1 ] ) )
  	{
  	case SLAP_CB_CONTINUE:
  		break;
  
  	case LDAP_SUCCESS:
  		j1++;
  		break;
  
  	default:
  		goto done;
  	}
  
  	/* put controls that go __after__ existing ones here */
  
  #ifdef SLAP_CONTROL_X_SESSION_TRACKING
  	/* FIXME: according to <draft-wahl-ldap-session>, 
  	 * the server should check if the control can be added
  	 * based on the identity of the client and so */
  
  	/* session tracking */
  	if ( LDAP_BACK_ST_REQUEST( li ) ) {
  		switch ( slap_ctrl_session_tracking_request_add( op, rs, &c[ j1 + j2 ] ) ) {
  		case SLAP_CB_CONTINUE:
  			break;
  
  		case LDAP_SUCCESS:
  			j2++;
  			break;
  
  		default:
  			goto done;
  		}
  	}
  #endif /* SLAP_CONTROL_X_SESSION_TRACKING */
  
  	if ( rs->sr_err == SLAP_CB_CONTINUE ) {
  		rs->sr_err = LDAP_SUCCESS;
  	}
  
  	/* if nothing to do, just bail out */
  	if ( j1 == 0 && j2 == 0 ) {
  		goto done;
  	}
  
  	assert( j1 + j2 <= (int) (sizeof( c )/sizeof( c[0] )) );
  
  	if ( op->o_ctrls ) {
  		for ( n = 0; op->o_ctrls[ n ]; n++ )
  			/* just count ctrls */ ;
  	}
  
  	ctrls = op->o_tmpalloc( (n + j1 + j2 + 1) * sizeof( LDAPControl * ) + ( j1 + j2 ) * sizeof( LDAPControl ),
  			op->o_tmpmemctx );
  	if ( j1 ) {
  		ctrls[ 0 ] = (LDAPControl *)&ctrls[ n + j1 + j2 + 1 ];
  		*ctrls[ 0 ] = c[ 0 ];
  		for ( i = 1; i < j1; i++ ) {
  			ctrls[ i ] = &ctrls[ 0 ][ i ];
  			*ctrls[ i ] = c[ i ];
  		}
  	}
  
  	i = 0;
  	if ( op->o_ctrls ) {
  		for ( i = 0; op->o_ctrls[ i ]; i++ ) {
  			ctrls[ i + j1 ] = op->o_ctrls[ i ];
  		}
  	}
  
  	n += j1;
  	if ( j2 ) {
  		ctrls[ n ] = (LDAPControl *)&ctrls[ n + j2 + 1 ] + j1;
  		*ctrls[ n ] = c[ j1 ];
  		for ( i = 1; i < j2; i++ ) {
  			ctrls[ n + i ] = &ctrls[ n ][ i ];
  			*ctrls[ n + i ] = c[ i ];
  		}
  	}
  
  	ctrls[ n + j2 ] = NULL;
  
  done:;
  	if ( ctrls == NULL ) {
  		ctrls = op->o_ctrls;
  	}
  
  	*pctrls = ctrls;
  	
  	return rs->sr_err;
  }
  
  int
  ldap_back_controls_free( Operation *op, SlapReply *rs, LDAPControl ***pctrls )
  {
  	LDAPControl	**ctrls = *pctrls;
  
  	/* we assume that the controls added by the proxy come first,
  	 * so as soon as we find op->o_ctrls[ 0 ] we can stop */
  	if ( ctrls && ctrls != op->o_ctrls ) {
  		int		i = 0, n = 0, n_added;
  		LDAPControl	*lower, *upper;
  
  		assert( ctrls[ 0 ] != NULL );
  
  		for ( n = 0; ctrls[ n ] != NULL; n++ )
  			/* count 'em */ ;
  
  		if ( op->o_ctrls ) {
  			for ( i = 0; op->o_ctrls[ i ] != NULL; i++ )
  				/* count 'em */ ;
  		}
  
  		n_added = n - i;
  		lower = (LDAPControl *)&ctrls[ n ];
  		upper = &lower[ n_added ];
  
  		for ( i = 0; ctrls[ i ] != NULL; i++ ) {
  			if ( ctrls[ i ] < lower || ctrls[ i ] >= upper ) {
  				/* original; don't touch */
  				continue;
  			}
  
  			if ( !BER_BVISNULL( &ctrls[ i ]->ldctl_value ) ) {
  				op->o_tmpfree( ctrls[ i ]->ldctl_value.bv_val, op->o_tmpmemctx );
  			}
  		}
  
  		op->o_tmpfree( ctrls, op->o_tmpmemctx );
  	} 
  
  	*pctrls = NULL;
  
  	return 0;
  }
  
  int
  ldap_back_conn2str( const ldapconn_base_t *lc, char *buf, ber_len_t buflen )
  {
  	char tbuf[ SLAP_TEXT_BUFLEN ];
  	char *ptr = buf, *end = buf + buflen;
  	int len;
  
  	if ( ptr + sizeof("conn=") > end ) return -1;
  	ptr = lutil_strcopy( ptr, "conn=" );
  
  	len = ldap_back_connid2str( lc, ptr, (ber_len_t)(end - ptr) );
  	ptr += len;
  	if ( ptr >= end ) return -1;
  
  	if ( !BER_BVISNULL( &lc->lcb_local_ndn ) ) {
  		if ( ptr + sizeof(" DN=\"\"") + lc->lcb_local_ndn.bv_len > end ) return -1;
  		ptr = lutil_strcopy( ptr, " DN=\"" );
  		ptr = lutil_strncopy( ptr, lc->lcb_local_ndn.bv_val, lc->lcb_local_ndn.bv_len );
  		*ptr++ = '"';
  	}
  
  	if ( lc->lcb_create_time != 0 ) {
  		len = snprintf( tbuf, sizeof(tbuf), "%ld", lc->lcb_create_time );
  		if ( ptr + sizeof(" created=") + len >= end ) return -1;
  		ptr = lutil_strcopy( ptr, " created=" );
  		ptr = lutil_strcopy( ptr, tbuf );
  	}
  
  	if ( lc->lcb_time != 0 ) {
  		len = snprintf( tbuf, sizeof(tbuf), "%ld", lc->lcb_time );
  		if ( ptr + sizeof(" modified=") + len >= end ) return -1;
  		ptr = lutil_strcopy( ptr, " modified=" );
  		ptr = lutil_strcopy( ptr, tbuf );
  	}
  
  	len = snprintf( tbuf, sizeof(tbuf), "%u", lc->lcb_refcnt );
  	if ( ptr + sizeof(" refcnt=") + len >= end ) return -1;
  	ptr = lutil_strcopy( ptr, " refcnt=" );
  	ptr = lutil_strcopy( ptr, tbuf );
  
  	return ptr - buf;
  }
  
  int
  ldap_back_connid2str( const ldapconn_base_t *lc, char *buf, ber_len_t buflen )
  {
  	static struct berval conns[] = {
  		BER_BVC("ROOTDN"),
  		BER_BVC("ROOTDN-TLS"),
  		BER_BVC("ANON"),
  		BER_BVC("ANON-TLS"),
  		BER_BVC("BIND"),
  		BER_BVC("BIND-TLS"),
  		BER_BVNULL
  	};
  
  	int len = 0;
  
  	if ( LDAP_BACK_PCONN_ISPRIV( (const ldapconn_t *)lc ) ) {
  		long cid;
  		struct berval *bv;
  
  		cid = (long)lc->lcb_conn;
  		assert( cid >= LDAP_BACK_PCONN_FIRST && cid < LDAP_BACK_PCONN_LAST );
  
  		bv = &conns[ cid ];
  
  		if ( bv->bv_len >= buflen ) {
  			return bv->bv_len + 1;
  		}
  
  		len = bv->bv_len;
  		lutil_strncopy( buf, bv->bv_val, bv->bv_len + 1 );
  
  	} else {
  		len = snprintf( buf, buflen, "%lu", lc->lcb_conn->c_connid );
  	}
  
  	return len;
  }
  