+static int
+ldap_back_prepare_conn( struct ldapconn **lcp, Operation *op, SlapReply *rs, ldap_back_send_t sendok )
+{
+ struct ldapinfo *li = (struct ldapinfo *)op->o_bd->be_private;
+ int vers = op->o_protocol;
+ LDAP *ld = NULL;
+
+ assert( lcp != NULL );
+
+ rs->sr_err = ldap_initialize( &ld, li->url );
+ 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.
+ */
+ ldap_set_option( ld, LDAP_OPT_PROTOCOL_VERSION, (const void *)&vers );
+
+ /* automatically chase referrals ("[dont-]chase-referrals" statement) */
+ if ( LDAP_BACK_CHASE_REFERRALS( li ) ) {
+ ldap_set_option( ld, LDAP_OPT_REFERRALS, LDAP_OPT_ON );
+ }
+
+#ifdef HAVE_TLS
+ /* start TLS ("tls-[try-]{start,propagate}" statements) */
+ if ( ( LDAP_BACK_USE_TLS( li ) || ( op->o_conn->c_is_tls && LDAP_BACK_PROPAGATE_TLS( li ) ) )
+ && !ldap_is_ldaps_url( li->url ) )
+ {
+#ifdef SLAP_STARTTLS_ASYNCHRONOUS
+ /*
+ * use asynchronous StartTLS
+ * in case, chase referral (not implemented yet)
+ */
+ int msgid;
+
+ rs->sr_err = ldap_start_tls( ld, NULL, NULL, &msgid );
+ if ( rs->sr_err == LDAP_SUCCESS ) {
+ LDAPMessage *res = NULL;
+ int rc, retries = 1;
+ struct timeval tv = { 0, 0 };
+
+retry:;
+ rc = ldap_result( ld, msgid, LDAP_MSG_ALL, &tv, &res );
+ if ( rc < 0 ) {
+ rs->sr_err = LDAP_OTHER;
+
+ } else if ( rc == 0 ) {
+ if ( retries ) {
+ retries--;
+ tv.tv_sec = 0;
+ tv.tv_usec = 100000;
+ goto retry;
+ }
+ rs->sr_err = LDAP_OTHER;
+
+ } else if ( rc == LDAP_RES_EXTENDED ) {
+ struct berval *data = NULL;
+
+ rs->sr_err = ldap_parse_extended_result( ld, res,
+ NULL, &data, 0 );
+ if ( rs->sr_err == LDAP_SUCCESS ) {
+ rs->sr_err = ldap_result2error( ld, res, 1 );
+ res = NULL;
+
+ /* FIXME: in case a referral
+ * is returned, should we try
+ * using it instead of the
+ * configured URI? */
+ if ( rs->sr_err == LDAP_SUCCESS ) {
+ ldap_install_tls( ld );
+
+ } else if ( rs->sr_err == LDAP_REFERRAL ) {
+ rs->sr_err = LDAP_OTHER;
+ rs->sr_text = "unwilling to chase referral returned by Start TLS exop";
+ }
+
+ if ( data ) {
+ if ( data->bv_val ) {
+ ber_memfree( data->bv_val );
+ }
+ ber_memfree( data );
+ }
+ }
+
+ } else {
+ rs->sr_err = LDAP_OTHER;
+ }
+
+ if ( res != NULL ) {
+ ldap_msgfree( res );
+ }
+ }
+#else /* ! SLAP_STARTTLS_ASYNCHRONOUS */
+ /*
+ * use synchronous StartTLS
+ */
+ rs->sr_err = 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 */
+ if ( rs->sr_err == LDAP_SERVER_DOWN
+ || ( rs->sr_err != LDAP_SUCCESS && LDAP_BACK_TLS_CRITICAL( li ) ) )
+ {
+ ldap_unbind_ext( ld, NULL, NULL );
+ goto error_return;
+ }
+
+ /* in case Start TLS is not critical */
+ rs->sr_err = LDAP_SUCCESS;
+ }
+#endif /* HAVE_TLS */
+
+ if ( *lcp == NULL ) {
+ *lcp = (struct ldapconn *)ch_calloc( 1, sizeof( struct ldapconn ) );
+ }
+ (*lcp)->lc_ld = ld;
+ (*lcp)->lc_refcnt = 1;
+
+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 = "ldap_initialize() failed";
+ }
+ send_ldap_result( op, rs );
+ rs->sr_text = NULL;
+ }
+ }
+
+ return rs->sr_err;
+}
+