text: /* database.c - deals with database subsystem */
  /* $OpenLDAP$ */
  /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   *
   * Copyright 2001-2015 The OpenLDAP Foundation.
   * Portions Copyright 2001-2003 Pierangelo Masarati.
   * 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 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 Pierangelo Masarati for inclusion
   * in OpenLDAP Software.
   */
  
  #include "portable.h"
  
  #include <stdio.h>
  #include <ac/string.h>
  #include <ac/unistd.h>
  
  #include "slap.h"
  #include "back-monitor.h"
  
  #if defined(LDAP_SLAPI)
  #include "slapi.h"
  static int monitor_back_add_plugin( monitor_info_t *mi, Backend *be, Entry *e );
  #endif /* defined(LDAP_SLAPI) */
  
  static int
  monitor_subsys_database_modify(
  	Operation	*op,
  	SlapReply	*rs,
  	Entry		*e );
  
  static struct restricted_ops_t {
  	struct berval	op;
  	unsigned int	tag;
  } restricted_ops[] = {
  	{ BER_BVC( "add" ),			SLAP_RESTRICT_OP_ADD },
  	{ BER_BVC( "bind" ),			SLAP_RESTRICT_OP_BIND },
  	{ BER_BVC( "compare" ),			SLAP_RESTRICT_OP_COMPARE },
  	{ BER_BVC( "delete" ),			SLAP_RESTRICT_OP_DELETE },
  	{ BER_BVC( "extended" ),		SLAP_RESTRICT_OP_EXTENDED },
  	{ BER_BVC( "modify" ),			SLAP_RESTRICT_OP_MODIFY },
  	{ BER_BVC( "rename" ),			SLAP_RESTRICT_OP_RENAME },
  	{ BER_BVC( "search" ),			SLAP_RESTRICT_OP_SEARCH },
  	{ BER_BVNULL,				0 }
  }, restricted_exops[] = {
  	{ BER_BVC( LDAP_EXOP_START_TLS ),	SLAP_RESTRICT_EXOP_START_TLS },
  	{ BER_BVC( LDAP_EXOP_MODIFY_PASSWD ),	SLAP_RESTRICT_EXOP_MODIFY_PASSWD },
  	{ BER_BVC( LDAP_EXOP_WHO_AM_I ),	SLAP_RESTRICT_EXOP_WHOAMI },
  	{ BER_BVC( LDAP_EXOP_CANCEL ),	SLAP_RESTRICT_EXOP_CANCEL },
  	{ BER_BVNULL,				0 }
  };
  
  static int
  init_readOnly( monitor_info_t *mi, Entry *e, slap_mask_t restrictops )
  {
  	struct berval	*tf = ( ( restrictops & SLAP_RESTRICT_OP_MASK ) == SLAP_RESTRICT_OP_WRITES ) ?
  		(struct berval *)&slap_true_bv : (struct berval *)&slap_false_bv;
  
  	return attr_merge_one( e, mi->mi_ad_readOnly, tf, NULL );
  }
  
  static int
  init_restrictedOperation( monitor_info_t *mi, Entry *e, slap_mask_t restrictops )
  {
  	int	i, rc;
  
  	for ( i = 0; restricted_ops[ i ].op.bv_val; i++ ) {
  		if ( restrictops & restricted_ops[ i ].tag ) {
  			rc = attr_merge_one( e, mi->mi_ad_restrictedOperation,
  					&restricted_ops[ i ].op,
  					&restricted_ops[ i ].op );
  			if ( rc ) {
  				return rc;
  			}
  		}
  	}
  
  	for ( i = 0; restricted_exops[ i ].op.bv_val; i++ ) {
  		if ( restrictops & restricted_exops[ i ].tag ) {
  			rc = attr_merge_one( e, mi->mi_ad_restrictedOperation,
  					&restricted_exops[ i ].op,
  					&restricted_exops[ i ].op );
  			if ( rc ) {
  				return rc;
  			}
  		}
  	}
  
  	return LDAP_SUCCESS;
  }
  
  static int
  monitor_subsys_overlay_init_one(
  	monitor_info_t		*mi,
  	BackendDB		*be,
  	monitor_subsys_t	*ms,
  	monitor_subsys_t	*ms_overlay,
  	slap_overinst		*on,
  	Entry			*e_database,
  	Entry			**ep_overlay )
  {
  	char			buf[ BACKMONITOR_BUFSIZE ];
  	int			j, o;
  	Entry			*e_overlay;
  	slap_overinst		*on2;
  	slap_overinfo		*oi = NULL;
  	BackendInfo		*bi;
  	monitor_entry_t		*mp_overlay;
  	struct berval		bv;
  
  	assert( overlay_is_over( be ) );
  
  	oi = (slap_overinfo *)be->bd_info->bi_private;
  	bi = oi->oi_orig;
  
  	/* find the overlay number, o */
  	for ( o = 0, on2 = oi->oi_list; on2 && on2 != on; on2 = on2->on_next, o++ )
  		;
  
  	if ( on2 == NULL ) {
  		return -1;
  	}
  
  	/* find the overlay type number, j */
  	for ( on2 = overlay_next( NULL ), j = 0; on2; on2 = overlay_next( on2 ), j++ ) {
  		if ( on2->on_bi.bi_type == on->on_bi.bi_type ) {
  			break;
  		}
  	}
  	assert( on2 != NULL );
  
  	bv.bv_len = snprintf( buf, sizeof( buf ), "cn=Overlay %d", o );
  	bv.bv_val = buf;
  
  	e_overlay = monitor_entry_stub( &e_database->e_name, &e_database->e_nname, &bv,
  		mi->mi_oc_monitoredObject, NULL, NULL );
  
  	if ( e_overlay == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_overlay_init_one: "
  			"unable to create entry "
  			"\"cn=Overlay %d,%s\"\n",
  			o, e_database->e_name.bv_val, 0 );
  		return( -1 );
  	}
  	ber_str2bv( on->on_bi.bi_type, 0, 0, &bv );
  	attr_merge_normalize_one( e_overlay, mi->mi_ad_monitoredInfo, &bv, NULL );
  
  	bv.bv_len = snprintf( buf, sizeof( buf ), "cn=Overlay %d,%s",
  		j, ms_overlay->mss_dn.bv_val );
  	bv.bv_val = buf;
  	attr_merge_normalize_one( e_overlay, slap_schema.si_ad_seeAlso,
  		&bv, NULL );
  
  	if ( SLAP_MONITOR( be ) ) {
  		attr_merge( e_overlay, slap_schema.si_ad_monitorContext,
  				be->be_suffix, be->be_nsuffix );
  
  	} else {
  		attr_merge( e_overlay, slap_schema.si_ad_namingContexts,
  				be->be_suffix, NULL );
  	}
  
  	mp_overlay = monitor_entrypriv_create();
  	if ( mp_overlay == NULL ) {
  		return -1;
  	}
  	e_overlay->e_private = ( void * )mp_overlay;
  	mp_overlay->mp_info = ms;
  	mp_overlay->mp_flags = ms->mss_flags | MONITOR_F_SUB;
  	
  	if ( monitor_cache_add( mi, e_overlay ) ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_overlay_init_one: "
  			"unable to add entry "
  			"\"cn=Overlay %d,%s\"\n",
  			o, e_database->e_name.bv_val, 0 );
  		return -1;
  	}
  
  	*ep_overlay = e_overlay;
  	ep_overlay = &mp_overlay->mp_next;
  
  	return 0;
  }
  
  static int
  monitor_subsys_database_init_one(
  	monitor_info_t		*mi,
  	BackendDB		*be,
  	monitor_subsys_t	*ms,
  	monitor_subsys_t	*ms_backend,
  	monitor_subsys_t	*ms_overlay,
  	struct berval		*rdn,
  	Entry			*e_database,
  	Entry			***epp )
  {
  	char			buf[ BACKMONITOR_BUFSIZE ];
  	int			j;
  	slap_overinfo		*oi = NULL;
  	BackendInfo		*bi, *bi2;
  	Entry			*e;
  	monitor_entry_t		*mp;
  	char			*rdnval = strchr( rdn->bv_val, '=' ) + 1;
  	struct berval		bv;
  
  	bi = be->bd_info;
  
  	if ( be->be_suffix == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init_one: "
  			"missing suffix for %s\n",
  			rdnval, 0, 0 );
  		return( -1 );
  	}
  
  	if ( overlay_is_over( be ) ) {
  		oi = (slap_overinfo *)be->bd_info->bi_private;
  		bi = oi->oi_orig;
  	}
  
  	e = monitor_entry_stub( &ms->mss_dn, &ms->mss_ndn, rdn,
  		mi->mi_oc_monitoredObject, NULL, NULL );
  
  	if ( e == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init_one: "
  			"unable to create entry \"%s,%s\"\n",
  			rdn->bv_val, ms->mss_dn.bv_val, 0 );
  		return( -1 );
  	}
  
  	ber_str2bv( bi->bi_type, 0, 0, &bv );
  	attr_merge_normalize_one( e, mi->mi_ad_monitoredInfo, &bv, NULL );
  	attr_merge_one( e, mi->mi_ad_monitorIsShadow,
  		SLAP_SHADOW( be ) ? (struct berval *)&slap_true_bv :
  			(struct berval *)&slap_false_bv, NULL );
  
  	if ( SLAP_MONITOR( be ) ) {
  		attr_merge( e, slap_schema.si_ad_monitorContext,
  				be->be_suffix, be->be_nsuffix );
  		attr_merge( e_database, slap_schema.si_ad_monitorContext,
  				be->be_suffix, be->be_nsuffix );
  
  	} else {
  		attr_merge( e, slap_schema.si_ad_namingContexts,
  			be->be_suffix, NULL );
  		attr_merge( e_database, slap_schema.si_ad_namingContexts,
  			be->be_suffix, NULL );
  
  		if ( SLAP_GLUE_SUBORDINATE( be ) ) {
  			BackendDB *sup_be = select_backend( &be->be_nsuffix[ 0 ], 1 );
  			if ( sup_be == NULL ) {
  				Debug( LDAP_DEBUG_ANY,
  					"monitor_subsys_database_init: "
  					"unable to get superior for %s\n",
  					be->be_suffix[ 0 ].bv_val, 0, 0 );
  
  			} else {
  				attr_merge( e, mi->mi_ad_monitorSuperiorDN,
  					sup_be->be_suffix, sup_be->be_nsuffix );
  			}
  		}
  	}
  
  	(void)init_readOnly( mi, e, be->be_restrictops );
  	(void)init_restrictedOperation( mi, e, be->be_restrictops );
  
  	if ( SLAP_SHADOW( be ) && be->be_update_refs ) {
  		attr_merge_normalize( e, mi->mi_ad_monitorUpdateRef,
  				be->be_update_refs, NULL );
  	}
  
  	if ( oi != NULL ) {
  		slap_overinst	*on = oi->oi_list,
  				*on1 = on;
  
  		for ( ; on; on = on->on_next ) {
  			slap_overinst		*on2;
  
  			for ( on2 = on1; on2 != on; on2 = on2->on_next ) {
  				if ( on2->on_bi.bi_type == on->on_bi.bi_type ) {
  					break;
  				}
  			}
  
  			if ( on2 != on ) {
  				break;
  			}
  			
  			ber_str2bv( on->on_bi.bi_type, 0, 0, &bv );
  			attr_merge_normalize_one( e, mi->mi_ad_monitorOverlay,
  					&bv, NULL );
  
  			/* find the overlay number, j */
  			for ( on2 = overlay_next( NULL ), j = 0; on2; on2 = overlay_next( on2 ), j++ ) {
  				if ( on2->on_bi.bi_type == on->on_bi.bi_type ) {
  					break;
  				}
  			}
  			assert( on2 != NULL );
  
  			snprintf( buf, sizeof( buf ), 
  				"cn=Overlay %d,%s", 
  				j, ms_overlay->mss_dn.bv_val );
  			ber_str2bv( buf, 0, 0, &bv );
  			attr_merge_normalize_one( e,
  					slap_schema.si_ad_seeAlso,
  					&bv, NULL );
  		}
  	}
  
  	j = -1;
  	LDAP_STAILQ_FOREACH( bi2, &backendInfo, bi_next ) {
  		j++;
  		if ( bi2->bi_type == bi->bi_type ) {
  			snprintf( buf, sizeof( buf ), 
  				"cn=Backend %d,%s", 
  				j, ms_backend->mss_dn.bv_val );
  			bv.bv_val = buf;
  			bv.bv_len = strlen( buf );
  			attr_merge_normalize_one( e,
  					slap_schema.si_ad_seeAlso,
  					&bv, NULL );
  			break;
  		}
  	}
  	/* we must find it! */
  	assert( j >= 0 );
  
  	mp = monitor_entrypriv_create();
  	if ( mp == NULL ) {
  		return -1;
  	}
  	e->e_private = ( void * )mp;
  	mp->mp_info = ms;
  	mp->mp_flags = ms->mss_flags
  		| MONITOR_F_SUB;
  
  	if ( monitor_cache_add( mi, e ) ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init_one: "
  			"unable to add entry \"%s,%s\"\n",
  			rdn->bv_val, ms->mss_dn.bv_val, 0 );
  		return( -1 );
  	}
  
  #if defined(LDAP_SLAPI)
  	monitor_back_add_plugin( mi, be, e );
  #endif /* defined(LDAP_SLAPI) */
  
  	if ( oi != NULL ) {
  		Entry		**ep_overlay = &mp->mp_children;
  		slap_overinst	*on = oi->oi_list;
  
  		for ( ; on; on = on->on_next ) {
  			monitor_subsys_overlay_init_one( mi, be,
  				ms, ms_overlay, on, e, ep_overlay );
  		}
  	}
  
  	**epp = e;
  	*epp = &mp->mp_next;
  
  	return 0;
  }
  
  static int
  monitor_back_register_database_and_overlay(
  	BackendDB		*be,
  	struct slap_overinst	*on,
  	struct berval		*ndn_out )
  {
  	monitor_info_t		*mi;
  	Entry			*e_database, **ep;
  	int			i, rc;
  	monitor_entry_t		*mp;
  	monitor_subsys_t	*ms_backend,
  				*ms_database,
  				*ms_overlay;
  	struct berval		bv;
  	char			buf[ BACKMONITOR_BUFSIZE ];
  
  	assert( be_monitor != NULL );
  
  	if ( !monitor_subsys_is_opened() ) {
  		if ( on ) {
  			return monitor_back_register_overlay_limbo( be, on, ndn_out );
  
  		} else {
  			return monitor_back_register_database_limbo( be, ndn_out );
  		}
  	}
  
  	mi = ( monitor_info_t * )be_monitor->be_private;
  
  	ms_backend = monitor_back_get_subsys( SLAPD_MONITOR_BACKEND_NAME );
  	if ( ms_backend == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_back_register_database: "
  			"unable to get "
  			"\"" SLAPD_MONITOR_BACKEND_NAME "\" "
  			"subsystem\n",
  			0, 0, 0 );
  		return -1;
  	}
  
  	ms_database = monitor_back_get_subsys( SLAPD_MONITOR_DATABASE_NAME );
  	if ( ms_database == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_back_register_database: "
  			"unable to get "
  			"\"" SLAPD_MONITOR_DATABASE_NAME "\" "
  			"subsystem\n",
  			0, 0, 0 );
  		return -1;
  	}
  
  	ms_overlay = monitor_back_get_subsys( SLAPD_MONITOR_OVERLAY_NAME );
  	if ( ms_overlay == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_back_register_database: "
  			"unable to get "
  			"\"" SLAPD_MONITOR_OVERLAY_NAME "\" "
  			"subsystem\n",
  			0, 0, 0 );
  		return -1;
  	}
  
  	if ( monitor_cache_get( mi, &ms_database->mss_ndn, &e_database ) ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init: "
  			"unable to get entry \"%s\"\n",
  			ms_database->mss_ndn.bv_val, 0, 0 );
  		return( -1 );
  	}
  
  	mp = ( monitor_entry_t * )e_database->e_private;
  	for ( i = -1, ep = &mp->mp_children; *ep; i++ ) {
  		Attribute	*a;
  
  		a = attr_find( (*ep)->e_attrs, slap_schema.si_ad_namingContexts );
  		if ( a ) {
  			int		j, k;
  
  			/* FIXME: RFC 4512 defines namingContexts without an
  			 *        equality matching rule, making comparisons
  			 *        like this one tricky.  We use a_vals and
  			 *        be_suffix instead for now.
  			 */
  			for ( j = 0; !BER_BVISNULL( &a->a_vals[ j ] ); j++ ) {
  				for ( k = 0; !BER_BVISNULL( &be->be_suffix[ k ] ); k++ ) {
  					if ( dn_match( &a->a_vals[ j ],
  					               &be->be_suffix[ k ] ) ) {
  						rc = 0;
  						goto done;
  					}
  				}
  			}
  		}
  
  		mp = ( monitor_entry_t * )(*ep)->e_private;
  
  		assert( mp != NULL );
  		ep = &mp->mp_next;
  	}
  
  	bv.bv_val = buf;
  	bv.bv_len = snprintf( buf, sizeof( buf ), "cn=Database %d", i );
  	if ( bv.bv_len >= sizeof( buf ) ) {
  		rc = -1;
  		goto done;
  	}
  	
  	rc = monitor_subsys_database_init_one( mi, be,
  		ms_database, ms_backend, ms_overlay, &bv, e_database, &ep );
  	if ( rc != 0 ) {
  		goto done;
  	}
  	/* database_init_one advanced ep past where we want.
  	 * But it stored the entry we want in mp->mp_next.
  	 */
  	ep = &mp->mp_next;
  
  done:;
  	monitor_cache_release( mi, e_database );
  	if ( rc == 0 && ndn_out && ep && *ep ) {
  		if ( on ) {
  			Entry *e_ov;
  			struct berval ov_type;
  
  			ber_str2bv( on->on_bi.bi_type, 0, 0, &ov_type );
  
  			mp = ( monitor_entry_t * ) (*ep)->e_private;
  			for ( e_ov = mp->mp_children; e_ov; ) {
  				Attribute *a = attr_find( e_ov->e_attrs, mi->mi_ad_monitoredInfo );
  
  				if ( a != NULL && bvmatch( &a->a_nvals[ 0 ], &ov_type ) ) {
  					*ndn_out = e_ov->e_nname;
  					break;
  				}
  
  				mp = ( monitor_entry_t * ) e_ov->e_private;
  				e_ov = mp->mp_next;
  			}
  			
  		} else {
  			*ndn_out = (*ep)->e_nname;
  		}
  	}
  
  	return rc;
  }
  
  int
  monitor_back_register_database(
  	BackendDB		*be,
  	struct berval		*ndn_out )
  {
  	return monitor_back_register_database_and_overlay( be, NULL, ndn_out );
  }
  
  int
  monitor_back_register_overlay(
  	BackendDB		*be,
  	struct slap_overinst	*on,
  	struct berval		*ndn_out )
  {
  	return monitor_back_register_database_and_overlay( be, on, ndn_out );
  }
  
  int
  monitor_subsys_database_init(
  	BackendDB		*be,
  	monitor_subsys_t	*ms )
  {
  	monitor_info_t		*mi;
  	Entry			*e_database, **ep;
  	int			i, rc;
  	monitor_entry_t		*mp;
  	monitor_subsys_t	*ms_backend,
  				*ms_overlay;
  	struct berval		bv;
  
  	assert( be != NULL );
  
  	ms->mss_modify = monitor_subsys_database_modify;
  
  	mi = ( monitor_info_t * )be->be_private;
  
  	ms_backend = monitor_back_get_subsys( SLAPD_MONITOR_BACKEND_NAME );
  	if ( ms_backend == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init: "
  			"unable to get "
  			"\"" SLAPD_MONITOR_BACKEND_NAME "\" "
  			"subsystem\n",
  			0, 0, 0 );
  		return -1;
  	}
  
  	ms_overlay = monitor_back_get_subsys( SLAPD_MONITOR_OVERLAY_NAME );
  	if ( ms_overlay == NULL ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init: "
  			"unable to get "
  			"\"" SLAPD_MONITOR_OVERLAY_NAME "\" "
  			"subsystem\n",
  			0, 0, 0 );
  		return -1;
  	}
  
  	if ( monitor_cache_get( mi, &ms->mss_ndn, &e_database ) ) {
  		Debug( LDAP_DEBUG_ANY,
  			"monitor_subsys_database_init: "
  			"unable to get entry \"%s\"\n",
  			ms->mss_ndn.bv_val, 0, 0 );
  		return( -1 );
  	}
  
  	(void)init_readOnly( mi, e_database, frontendDB->be_restrictops );
  	(void)init_restrictedOperation( mi, e_database, frontendDB->be_restrictops );
  
  	mp = ( monitor_entry_t * )e_database->e_private;
  	mp->mp_children = NULL;
  	ep = &mp->mp_children;
  
  	BER_BVSTR( &bv, "cn=Frontend" );
  	rc = monitor_subsys_database_init_one( mi, frontendDB,
  		ms, ms_backend, ms_overlay, &bv, e_database, &ep );
  	if ( rc != 0 ) {
  		return rc;
  	}
  
  	i = -1;
  	LDAP_STAILQ_FOREACH( be, &backendDB, be_next ) {
  		char		buf[ BACKMONITOR_BUFSIZE ];
  
  		bv.bv_val = buf;
  		bv.bv_len = snprintf( buf, sizeof( buf ), "cn=Database %d", ++i );
  		if ( bv.bv_len >= sizeof( buf ) ) {
  			return -1;
  		}
  		
  		rc = monitor_subsys_database_init_one( mi, be,
  			ms, ms_backend, ms_overlay, &bv, e_database, &ep );
  		if ( rc != 0 ) {
  			return rc;
  		}
  	}
  	
  	monitor_cache_release( mi, e_database );
  
  	return( 0 );
  }
  
  /*
   * v: array of values
   * cur: must not contain the tags corresponding to the values in v
   * delta: will contain the tags corresponding to the values in v
   */
  static int
  value_mask( BerVarray v, slap_mask_t cur, slap_mask_t *delta )
  {
  	for ( ; !BER_BVISNULL( v ); v++ ) {
  		struct restricted_ops_t		*rops;
  		int				i;
  
  		if ( OID_LEADCHAR( v->bv_val[ 0 ] ) ) {
  			rops = restricted_exops;
  
  		} else {
  			rops = restricted_ops;
  		}
  
  		for ( i = 0; !BER_BVISNULL( &rops[ i ].op ); i++ ) {
  			if ( ber_bvstrcasecmp( v, &rops[ i ].op ) != 0 ) {
  				continue;
  			}
  
  			if ( rops[ i ].tag & *delta ) {
  				return LDAP_OTHER;
  			}
  
  			if ( rops[ i ].tag & cur ) {
  				return LDAP_OTHER;
  			}
  
  			cur |= rops[ i ].tag;
  			*delta |= rops[ i ].tag;
  
  			break;
  		}
  
  		if ( BER_BVISNULL( &rops[ i ].op ) ) {
  			return LDAP_INVALID_SYNTAX;
  		}
  	}
  
  	return LDAP_SUCCESS;
  }
  
  static int
  monitor_subsys_database_modify(
  	Operation	*op,
  	SlapReply	*rs,
  	Entry		*e )
  {
  	monitor_info_t	*mi = (monitor_info_t *)op->o_bd->be_private;
  	int		rc = LDAP_OTHER;
  	Attribute	*save_attrs, *a;
  	Modifications	*ml;
  	Backend		*be;
  	int		ro_gotval = 1, i, n;
  	slap_mask_t	rp_add = 0, rp_delete = 0, rp_cur;
  	struct berval	*tf;
  	
  	i = sscanf( e->e_nname.bv_val, "cn=database %d,", &n );
  	if ( i != 1 ) {
  		return SLAP_CB_CONTINUE;
  	}
  
  	if ( n < 0 || n >= nBackendDB ) {
  		rs->sr_text = "invalid database index";
  		return ( rs->sr_err = LDAP_NO_SUCH_OBJECT );
  	}
  
  	LDAP_STAILQ_FOREACH( be, &backendDB, be_next ) {
  		if ( n == 0 ) {
  			break;
  		}
  		n--;
  	}
  	/* do not allow some changes on back-monitor (needs work)... */
  	if ( SLAP_MONITOR( be ) ) {
  		rs->sr_text = "no modifications allowed to monitor database entry";
  		return ( rs->sr_err = LDAP_UNWILLING_TO_PERFORM );
  	}
  		
  	rp_cur = be->be_restrictops;
  
  	save_attrs = e->e_attrs;
  	e->e_attrs = attrs_dup( e->e_attrs );
  
  	for ( ml = op->orm_modlist; ml; ml = ml->sml_next ) {
  		Modification *mod = &ml->sml_mod;
  
  		if ( mod->sm_desc == mi->mi_ad_readOnly ) {
  			int	val = -1;
  
  			if ( mod->sm_values ) {
  				if ( !BER_BVISNULL( &mod->sm_values[ 1 ] ) ) {
  					rs->sr_text = "attempting to modify multiple values of single-valued attribute";
  					rc = rs->sr_err = LDAP_CONSTRAINT_VIOLATION;
  					goto done;
  				}
  
  				if ( bvmatch( &slap_true_bv, mod->sm_values )) {
  					val = 1;
  
  				} else if ( bvmatch( &slap_false_bv, mod->sm_values )) {
  					val = 0;
  
  				} else {
  					assert( 0 );
  					rc = rs->sr_err = LDAP_INVALID_SYNTAX;
  					goto done;
  				}
  			}
  
  			switch ( mod->sm_op ) {
  			case LDAP_MOD_DELETE:
  				if ( ro_gotval < 1 ) {
  					rc = rs->sr_err = LDAP_CONSTRAINT_VIOLATION;
  					goto done;
  				}
  				ro_gotval--;
  
  				if ( val == 0 && ( rp_cur & SLAP_RESTRICT_OP_WRITES ) == SLAP_RESTRICT_OP_WRITES ) {
  					rc = rs->sr_err = LDAP_NO_SUCH_ATTRIBUTE;
  					goto done;
  				}
  				
  				if ( val == 1 && ( rp_cur & SLAP_RESTRICT_OP_WRITES ) != SLAP_RESTRICT_OP_WRITES ) {
  					rc = rs->sr_err = LDAP_NO_SUCH_ATTRIBUTE;
  					goto done;
  				}
  				
  				break;
  
  			case LDAP_MOD_REPLACE:
  				ro_gotval = 0;
  				/* fall thru */
  
  			case LDAP_MOD_ADD:
  				if ( ro_gotval > 0 ) {
  					rc = rs->sr_err = LDAP_CONSTRAINT_VIOLATION;
  					goto done;
  				}
  				ro_gotval++;
  
  				if ( val == 1 ) {
  					rp_add |= (~rp_cur) & SLAP_RESTRICT_OP_WRITES;
  					rp_cur |= SLAP_RESTRICT_OP_WRITES;
  					rp_delete &= ~SLAP_RESTRICT_OP_WRITES;
  					
  				} else if ( val == 0 ) {
  					rp_delete |= rp_cur & SLAP_RESTRICT_OP_WRITES;
  					rp_cur &= ~SLAP_RESTRICT_OP_WRITES;
  					rp_add &= ~SLAP_RESTRICT_OP_WRITES;
  				}
  				break;
  
  			default:
  				rc = rs->sr_err = LDAP_OTHER;
  				goto done;
  			}
  
  		} else if ( mod->sm_desc == mi->mi_ad_restrictedOperation ) {
  			slap_mask_t	mask = 0;
  
  			switch ( mod->sm_op ) {
  			case LDAP_MOD_DELETE:
  				if ( mod->sm_values == NULL ) {
  					rp_delete = rp_cur;
  					rp_cur = 0;
  					rp_add = 0;
  					break;
  				}
  				rc = value_mask( mod->sm_values, ~rp_cur, &mask );
  				if ( rc == LDAP_SUCCESS ) {
  					rp_delete |= mask;
  					rp_add &= ~mask;
  					rp_cur &= ~mask;
  
  				} else if ( rc == LDAP_OTHER ) {
  					rc = LDAP_NO_SUCH_ATTRIBUTE;
  				}
  				break;
  
  			case LDAP_MOD_REPLACE:
  				rp_delete = rp_cur;
  				rp_cur = 0;
  				rp_add = 0;
  				/* fall thru */
  
  			case LDAP_MOD_ADD:
  				rc = value_mask( mod->sm_values, rp_cur, &mask );
  				if ( rc == LDAP_SUCCESS ) {
  					rp_add |= mask;
  					rp_cur |= mask;
  					rp_delete &= ~mask;
  
  				} else if ( rc == LDAP_OTHER ) {
  					rc = rs->sr_err = LDAP_TYPE_OR_VALUE_EXISTS;
  				}
  				break;
  
  			default:
  				rc = rs->sr_err = LDAP_OTHER;
  				break;
  			}
  
  			if ( rc != LDAP_SUCCESS ) {
  				goto done;
  			}
  
  		} else if ( is_at_operational( mod->sm_desc->ad_type )) {
  		/* accept all operational attributes */
  			attr_delete( &e->e_attrs, mod->sm_desc );
  			rc = attr_merge( e, mod->sm_desc, mod->sm_values,
  				mod->sm_nvalues );
  			if ( rc ) {
  				rc = rs->sr_err = LDAP_OTHER;
  				break;
  			}
  
  		} else {
  			rc = rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
  			break;
  		}
  	}
  
  	/* sanity checks: */
  	if ( ro_gotval < 1 ) {
  		rc = rs->sr_err = LDAP_CONSTRAINT_VIOLATION;
  		goto done;
  	}
  
  	if ( ( rp_cur & SLAP_RESTRICT_OP_EXTENDED ) && ( rp_cur & SLAP_RESTRICT_EXOP_MASK ) ) {
  		rc = rs->sr_err = LDAP_CONSTRAINT_VIOLATION;
  		goto done;
  	}
  
  	if ( rp_delete & rp_add ) {
  		rc = rs->sr_err = LDAP_OTHER;
  		goto done;
  	}
  
  	/* check current value of readOnly */
  	if ( ( rp_cur & SLAP_RESTRICT_OP_WRITES ) == SLAP_RESTRICT_OP_WRITES ) {
  		tf = (struct berval *)&slap_true_bv;
  
  	} else {
  		tf = (struct berval *)&slap_false_bv;
  	}
  
  	a = attr_find( e->e_attrs, mi->mi_ad_readOnly );
  	if ( a == NULL ) {
  		rc = LDAP_OTHER;
  		goto done;
  	}
  
  	if ( !bvmatch( &a->a_vals[ 0 ], tf ) ) {
  		attr_delete( &e->e_attrs, mi->mi_ad_readOnly );
  		rc = attr_merge_one( e, mi->mi_ad_readOnly, tf, tf );
  	}
  
  	if ( rc == LDAP_SUCCESS ) {
  		if ( rp_delete ) {
  			if ( rp_delete == be->be_restrictops ) {
  				attr_delete( &e->e_attrs, mi->mi_ad_restrictedOperation );
  
  			} else {
  				a = attr_find( e->e_attrs, mi->mi_ad_restrictedOperation );
  				if ( a == NULL ) {
  					rc = rs->sr_err = LDAP_OTHER;
  					goto done;
  				}
  
  				for ( i = 0; !BER_BVISNULL( &restricted_ops[ i ].op ); i++ ) {
  					if ( rp_delete & restricted_ops[ i ].tag ) {
  						int	j;
  					
  						for ( j = 0; !BER_BVISNULL( &a->a_nvals[ j ] ); j++ ) {
  							int		k;
  
  							if ( !bvmatch( &a->a_nvals[ j ], &restricted_ops[ i ].op ) ) {
  								continue;
  							}
  
  							ch_free( a->a_vals[ j ].bv_val );
  							ch_free( a->a_nvals[ j ].bv_val );
  
  							for ( k = j + 1; !BER_BVISNULL( &a->a_nvals[ k ] ); k++ ) {
  								a->a_vals[ k - 1 ] = a->a_vals[ k ];
  								a->a_nvals[ k - 1 ] = a->a_nvals[ k ];
  							}
  	
  							BER_BVZERO( &a->a_vals[ k - 1 ] );
  							BER_BVZERO( &a->a_nvals[ k - 1 ] );
  							a->a_numvals--;
  						}
  					}
  				}
  				
  				for ( i = 0; !BER_BVISNULL( &restricted_exops[ i ].op ); i++ ) {
  					if ( rp_delete & restricted_exops[ i ].tag ) {
  						int	j;
  					
  						for ( j = 0; !BER_BVISNULL( &a->a_nvals[ j ] ); j++ ) {
  							int		k;
  
  							if ( !bvmatch( &a->a_nvals[ j ], &restricted_exops[ i ].op ) ) {
  								continue;
  							}
  
  							ch_free( a->a_vals[ j ].bv_val );
  							ch_free( a->a_nvals[ j ].bv_val );
  
  							for ( k = j + 1; !BER_BVISNULL( &a->a_nvals[ k ] ); k++ ) {
  								a->a_vals[ k - 1 ] = a->a_vals[ k ];
  								a->a_nvals[ k - 1 ] = a->a_nvals[ k ];
  							}
  	
  							BER_BVZERO( &a->a_vals[ k - 1 ] );
  							BER_BVZERO( &a->a_nvals[ k - 1 ] );
  							a->a_numvals--;
  						}
  					}
  				}
  
  				if ( a->a_vals == NULL ) {
  					assert( a->a_numvals == 0 );
  
  					attr_delete( &e->e_attrs, mi->mi_ad_restrictedOperation );
  				}
  			}
  		}
  
  		if ( rp_add ) {
  			for ( i = 0; !BER_BVISNULL( &restricted_ops[ i ].op ); i++ ) {
  				if ( rp_add & restricted_ops[ i ].tag ) {
  					attr_merge_one( e, mi->mi_ad_restrictedOperation,
  							&restricted_ops[ i ].op,
  							&restricted_ops[ i ].op );
  				}
  			}
  
  			for ( i = 0; !BER_BVISNULL( &restricted_exops[ i ].op ); i++ ) {
  				if ( rp_add & restricted_exops[ i ].tag ) {
  					attr_merge_one( e, mi->mi_ad_restrictedOperation,
  							&restricted_exops[ i ].op,
  							&restricted_exops[ i ].op );
  				}
  			}
  		}
  	}
  
  	be->be_restrictops = rp_cur;
  
  done:;
  	if ( rc == LDAP_SUCCESS ) {
  		attrs_free( save_attrs );
  		rc = SLAP_CB_CONTINUE;
  
  	} else {
  		Attribute *tmp = e->e_attrs;
  		e->e_attrs = save_attrs;
  		attrs_free( tmp );
  	}
  	return rc;
  }
  
  #if defined(LDAP_SLAPI)
  static int
  monitor_back_add_plugin( monitor_info_t *mi, Backend *be, Entry *e_database )
  {
  	Slapi_PBlock	*pCurrentPB; 
  	int		i, rc = LDAP_SUCCESS;
  
  	if ( slapi_int_pblock_get_first( be, &pCurrentPB ) != LDAP_SUCCESS ) {
  		/*
  		 * LDAP_OTHER is returned if no plugins are installed
  		 */
  		rc = LDAP_OTHER;
  		goto done;
  	}
  
  	i = 0;
  	do {
  		Slapi_PluginDesc	*srchdesc;
  		char			buf[ BACKMONITOR_BUFSIZE ];
  		struct berval		bv;
  
  		rc = slapi_pblock_get( pCurrentPB, SLAPI_PLUGIN_DESCRIPTION,
  				&srchdesc );
  		if ( rc != LDAP_SUCCESS ) {
  			goto done;
  		}
  		if ( srchdesc ) {
  			snprintf( buf, sizeof(buf),
  					"plugin %d name: %s; "
  					"vendor: %s; "
  					"version: %s; "
  					"description: %s", 
  					i,
  					srchdesc->spd_id,
  					srchdesc->spd_vendor,
  					srchdesc->spd_version,
  					srchdesc->spd_description );
  		} else {
  			snprintf( buf, sizeof(buf),
  					"plugin %d name: <no description available>", i );
  		}
  
  		ber_str2bv( buf, 0, 0, &bv );
  		attr_merge_normalize_one( e_database,
  				mi->mi_ad_monitoredInfo, &bv, NULL );
  
  		i++;
  
  	} while ( ( slapi_int_pblock_get_next( &pCurrentPB ) == LDAP_SUCCESS )
  			&& ( pCurrentPB != NULL ) );
  
  done:
  	return rc;
  }
  #endif /* defined(LDAP_SLAPI) */
  