OpenBSD interop testing

[Nicolai]

Hello all,

Now that OpenBSD has tagged 6.8-beta it's a good time to report interop
testing of WireGuard.  I've been using the kernel implementation since
support was merged in June.  Every peer combination I've tried works
properly, it's a joy to use, and I'm excited for 6.7 users to upgrade
and start using the kernel implementation.

All OpenBSD-current machines are using the kernel implementation.  Here
are the interop tests, all on IPv4:

0. peer-A, peer-B
1. OpenBSD 6.7 amd64 wireguard-go, OpenBSD 6.7-current amd64
2. OpenBSD 6.7-current amd64, OpenBSD 6.7-current amd64
3. OpenBSD 6.8-beta amd64, OpenBSD 6.8-beta amd64
4. Debian 10 x86-64 backported kernel, OpenBSD 6.7-current amd64
5. Debian 10 x86-64 backported kernel, OpenBSD 6.8-beta amd64
6. iOS 13.5.1, OpenBSD 6.7-current amd64
7. iOS 13.6, OpenBSD 6.7-current amd64
8. iOS 13.7, OpenBSD 6.7-current amd64
9. iOS 13.7, OpenBSD 6.8-beta amd64
10. macOS 10.15.4 (Catalina), OpenBSD 6.7-current amd64
11. macOS 10.15.6 (Catalina), OpenBSD 6.8-beta amd64
12. Android 5.1, OpenBSD 6.7-current amd64
13. Android 5.1, OpenBSD 6.8-beta amd64
14. OpenBSD 6.7-current i386, OpenBSD 6.7 amd64 wireguard-go
15. OpenBSD 6.7-current i386 PSK, OpenBSD 6.7 amd64 wireguard-go PSK
16. OpenBSD 6.7-current amd64 PSK, OpenBSD 6.7-current amd64 PSK
17. OpenBSD 6.8-beta amd64, OpenBSD 6.7 amd64 wireguard-go

Thank you to all developers, users, and contributors, in particular Matt
and Jason for bringing WireGuard to OpenBSD, and to everyone who has
given code feedback on tech at .

Nicolai