Using WG for transport security in a p2p network

[Kalin KOZHUHAROV]

Hello Ximin,


On Thu, Apr 5, 2018 at 5:22 AM, Ximin Luo <ximin at dfinity.org> wrote:
> Our network churn is not expected to be very heavy, perhaps on the order of
> ~30 new connections per node per week or so. So any extra latency in the initial
> connection caused by this separation of layers, should not be significant.
> However this churn is probably higher than what current typical WG usages
> get exposed to.
>
Few times a day, I would even say few times per hour is a very normal use and
should not be strange, AFAIK.

> I'm also wondering how easy this would be to program. It would clearly be
> much more heavyweight than simply opening a socket, but I guess it can be done
> via invocations of the `wg` or `wg-quick` tools. Has anyone had any experience
> with this level of WG automation, could you share your thoughts?
>
Definitely not "hard", it will depend more on what you are trying to
achieve exactly.

> Would the program need any extra system-level privileges?
>
Yes for sure ;-D Adding interfaces is a admin task, using sudo or
similar should be trivial.

> Ideally we wouldn't need root, of course - does that mean we're forced to wait for a userspace WG library such
> as wireguard-rs? I understand there is a performance penalty here, but I'd have
> to run benchmarks to know if this affects our use-case significantly.
>
I don't think performance matters in your case, as it will be only
during setup; once setup,
all data goes to a socket/kernel and it doesn't matter how it was set up.

> Once the network is live, we'd need the transport protocol to be relatively
> stable, or at least be easily upgradeable - perhaps using the noise
> negotiation subprotocol to support two protocols during network upgrade times. This is
> an extra requirement that seems beyond WG's current main use-case so I was also
> wondering if that is something that you guys plan to cover.
>
Making it "support 2 protocols" in the design phase is a good practice
for availability.
It will introduce complexity, maintainability issues and thus possible
security issues.
Working out a "maintenance mode" might be easier.

Cheers,
Kalin.