Overlapping AllowedIPs Configuration

[Paul Zillmann]

Hello Toke,

thanks for your information.
I've seen a topic came up on the bird user mailing list which you have 
had crosslinked here.

In the mean time I've created this little python script: 
https://github.com/pzillmann/wireguard-dynamic-routing

At least it does the job for me. I think Janne's code needs some time go 
get integrated into upstream plus a few days until it is shipped with 
the distributions. (Maybe we see it in Debian 10?)

Until then there is this script. Feel free to give me some feedback.

- Paul

Am 06.06.19 um 12:09 schrieb Toke Høiland-Jørgensen:
> Paul Zillmann <paul at zil.li> writes:
>
>> Hello,
>>
>> we have the same problem here, although our allowed IP ranges should be
>> 0.0.0.0/0 for all peers.
>> We have OSPF traffic on the wireguard links so it should be task of the
>> Kernel's routing table to decide where to send what.
>>
>> The problem is that the allowed-ips configuration has multiple purposes:
>> routing table and firewall/packet filter. This introduces these
>> problems. It would be helpfull to get a compile flag or something else
>> to make this behavior optional.
> That is probably not going to happen; the crypto-routing is quite
> integral to Wireguard, and is an important security feature.
>
>> Right now Wireguard isn't very friendly to dynamic routing.
>>
>> I came up with multiple solutions:
>> - create multiple interfaces + tunnels.
>> or
>> - create a bash script that injects the Kernel's routing table into the
>> wg tool every other minute.
>>
>> Do you guys have a better idea? If not I would create the bash script.
> IMO, the "right" way to fix this is to make your routing daemon aware of
> wireguard and have it configure the routes directly into the wireguard
> table. That also gives you security for your routing protocol
> automatically (since only authenticated sources/destinations will be
> allowed), as long as you have a secure way of bootstrapping the
> wireguard keying.
>
> -Toke