New to Wireguard, it looks super interesting... quick questions:

1. If it uses UDP only, how does NAT traversal (firewall punch through)
work?

2. are there userspace implementations available...?

Experience thus far: The src packages that are in repos for centos 7 were
insufficient to compile. I downloaded full wireguard source and tried to
compile the wireguard kernel module on centos 7.3 with kernel 3.10, no
luck, lots of compile time header issues. I upgraded to kernel 4.10 and
could compile the wireguard module under kernel 4.10, but then got stuck on
how to compile the dependent modules;hey aren't specific to wireguard, but
rather generic modules that just weren't in the default 4.10 kernel and I'm
not sure how to build them.

[root@k0 src]# insmod ./wireguard.ko
insmod: ERROR: could not insert module ./wireguard.ko: Unknown symbol in
module
[root@k0 src]# dmesg
...
[77292.707469] wireguard: Unknown symbol udp_sock_create4 (err 0)
[77292.711122] wireguard: Unknown symbol udp_tunnel6_xmit_skb (err 0)
[77292.714899] wireguard: Unknown symbol udp_tunnel_sock_release (err 0)
[77292.718642] wireguard: Unknown symbol setup_udp_tunnel_sock (err 0)
[77292.722699] wireguard: Unknown symbol udp_sock_create6 (err 0)
[77292.726007] wireguard: Unknown symbol udp_tunnel_xmit_skb (err 0)
[root@k0 src]#

Anywho, a userland implementation would be easier to play with. Are such
out there?

Thanks!

Jason