Re: ospf on wg(4)

Le 30/01/2021 à 09:22, Kapetanakis Giannis a écrit :
> On 29/01/2021 23:32, Bastien Durel wrote:
>> Le 29/01/2021 à 17:44, Olivier Cherrier a écrit :
>>>     Hi,
>>>
>>> I'm trying to setup OSPF on a working Wireguard VPN using 6.8 amd64
>>> machines. This is what I get:
>>>
>>> # ospfd -dvvv
>>> id = "172.26.1.1"
>>> startup
>>> kr_init: priority filter enabled
>>> orig_rtr_lsa: area 0.0.0.0
>>> orig_rtr_lsa: stub net, interface wg0
>>> if_fsm: event UP resulted in action START and changing state for
>>> interface wg0 from DOWN to P2P
>>> send_packet: error sending packet to 224.0.0.5 on interface wg0: Network
>>> is unreachable
>>> send_hello: Network is unreachable
>>> [...]
>>>
>>>
>>>
>>> # ifconfig wg0
>>> wg0: flags=80c3<UP,BROADCAST,RUNNING,NOARP,MULTICAST> mtu 1420
>>>     index 23 priority 0 llprio 3
>>>     wgport 33222
>>>     wgpubkey XXX
>>>     wgpeer YYY
>>>         wgpka 23 (sec)
>>>         wgendpoint A.B.C.D 31502
>>>         tx: 4317366604, rx: 382870060
>>>         last handshake: 47 seconds ago
>>>         wgaip 192.168.1.0/24
>>>         wgaip 172.26.1.3/32
>>>     wgpeer WWW
>>>         wgpka 23 (sec)
>>>         wgendpoint E.F.G.H 15776
>>>         tx: 609183380, rx: 1523684
>>>         last handshake: 1 seconds ago
>>>         wgaip 172.26.0.0/24
>>>         wgaip 172.26.1.2/32
>>>     groups: wg
>>>     inet 172.26.1.1 netmask 0xffffff00 broadcast 172.26.1.255
>>>
>>>
>>> Is it possible to use a wg(4) interface for ospfd(8)?
>>>
>>> Thank you,
>>> Best.
>>>
>> Hello.
>>
>> It is possible, I use it myself. You have to allow multicast address
>> on wg(4) interface(s):
>> 225.0.0.5 for all OSPF routers
>> 224.0.0.6 for all DR/BDR
>>
>> (I use wgaip 0.0.0.0/0, so my config is not relavant for you)
>>
>> Regards,
>>
> Sorry to jump in, but does this also add routes for 225.0.0.{5,6} via wg0?
>
> If this is a case, this would be a problem for multiple interfaces.
>
> Or maybe wg(4) handles multicast differently than normal IP
>
> thanks
>
> G
>
Hello,

IFAIK, wgaip is not routing, using wgaip 0.0.0.0/0 does not add a
default route on interface.

Regards,

--
Bastien