bind.c

OpenLdap是LDAP的开源项目

		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 ) {
					int err;
					rc = ldap_parse_result( ld, res, &err,
						NULL, NULL, NULL, NULL, 1 );
					if ( rc == LDAP_SUCCESS ) {
						rc = err;
					}
					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;
	time_t		lc_time = (time_t)(-1);
#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;
	}

	/* 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
	ldap_pvt_thread_mutex_lock( &li->li_uri_mutex );
	rs->sr_err = ldap_back_start_tls( ld, op->o_protocol, &is_tls,
			li->li_uri, li->li_flags, li->li_nretries, &rs->sr_text );
	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... */
		lc_time = 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 ( lc_time != (time_t)(-1) ) {
		lc->lc_time = lc_time;
	}
#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 acl_authcDN is to be used; however, in some cases
		 * one already configured identity assertion with a highly
		 * privileged idassert_authcDN, so if acl_authcDN is NULL
		 * and idassert_authcDN is not, use the second 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 ( BER_BVISNULL( &li->li_acl_authcDN ) && !BER_BVISNULL( &li->li_idassert_authcDN ) ) {
				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 );

		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;