OSPF over openvpn; adjacency problems

[Thorsten Alteholz]

Hi,

I am trying to use OSPF over an openvpn link. tcpdump tells me that both 
ends send their HELLO packet but bird does not want to recognize them.

When looking at ospf_rc_hook() in proto/ospf/packet.c the HELLO packet 
arrives in bird, but is discarded because of "strange address combinations":

src_local is 0:
        sk->faddr = 10.25.0.26
        ifa->addr->prefix = 10.25.0.2
        ifa->addr->pxlen = 32

dst_mcast is 1:
        sk->laddr = 224.0.0.5
        ifa->all_routers = 224.0.0.5
        ifa->des_routers = 224.0.0.6

        dst_mcast = 1 || 0

From my point of view these values do not look that bad (the tun 
interface on this server has an address of 10.25.0.1 and on the client
it is 10.25.0.26). But of course (dst_mcast && !src_local) is 1 and the 
HELLO packet is ignored.

Does anybody have any idea what went wrong here?

Best regards
Thorsten


The OSPF configuration on the server:

protocol ospf {
        debug all;
        import all;
        export none;

        area 10.10.10.0 {
                interface "tun1" {
                        type ptp;
                        cost 2000;
                        neighbors {
                                10.25.0.1;
                        };
                };
        };

}