[Dovecot] auth-ldap not resetting connection state after failed bind

[Brendan Braybrook]

timo, i think i found a small problem with the ldap implementation:

when using auth_bind (this might be in all conditions, not just that one 
- i haven't tested further), if the server lost connection to the ldap 
server (ie, the ldap server died) dovecot-auth would never reconnect to 
the ldap server and all subsequent auth attempts would fail. after a 
little more digging, i discovered that if the ldap server went down and 
came back up before the next dovecot request then everything would be 
fine. however, if a request came in while the ldap server was down then 
dovecot-auth would "cache" that the server was unavailable and never 
recheck it.

i believe i tracked it down to a couple lines in db_ldap_bind and fixed 
it - dovecot-auth is reconnecting to ldap in the condition where it was 
not previously:

--- dovecot-1.0.3/src/auth/db-ldap.c    2007-10-15 18:26:55.983349000 +0000
+++ dovecot-1.0.3/src/auth/db-ldap.c.new        2007-10-15 
18:28:03.124136000 +0000
@@ -446,7 +446,10 @@
        msgid = ldap_bind(conn->ld, conn->set.dn, conn->set.dnpass,
                          LDAP_AUTH_SIMPLE);
        if (msgid == -1) {
-               db_ldap_connect_finish(conn, ldap_get_errno(conn));
+               if (db_ldap_connect_finish(conn, ldap_get_errno(conn)) < 
0) {
+      /* lost connection, close it */
+      ldap_conn_close(conn, TRUE);
+    }
                i_free(ldap_request);
                return -1;
        }