Fix UDP option for OpenVPN 2.4.7

re6st/plib.py

@@ -23,10 +23,12 @@ def openvpn(iface, encrypt, *args, **kw):
     logging.debug('%r', args)
     return utils.Popen(args, **kw)
 
-ovpn_link_mtu_dict = {'udp': 1432, 'udp6': 1450}
+ovpn_link_mtu_dict = {'udp4': 1432, 'udp6': 1450}
 
 def server(iface, max_clients, dh_path, fd, port, proto, encrypt, *args, **kw):
     client_script = '%s %s' % (ovpn_server, fd)
+    if proto == 'udp':
+        proto='udp4'
     try:
         args = ('--link-mtu', str(ovpn_link_mtu_dict[proto]),
                 # mtu-disc ignored for udp6 due to a bug in OpenVPN
@@ -50,6 +52,8 @@ def client(iface, address_list, encrypt, *args, **kw):
     # XXX: We'd like to pass <connection> sections at command-line.
     link_mtu = set()
     for ip, port, proto in address_list:
+        if proto == 'udp':
+            proto = 'udp4'
         remote += '--remote', ip, port, proto
         link_mtu.add(ovpn_link_mtu_dict.get(proto))
     link_mtu, = link_mtu