Hello,

i finally found the time to polish up my implementation of ethernet over gre for 9front.
This is based on nusb/ether. It uses gre from the ip stack. I tested it with OpenBSD egre.
For now only ipv4 is supported for the outside of the tunnel.

9front:
ip address is 192.168.178.21

egre 192.168.178.20
ip/ipconfig -m 1400 ether /net/etherG0 10.0.0.1 255.255.255.0

OpenBSD:

ifconfig egre0 create
ifconfig egre0 tunnel 192.168.178.20 192.168.178.21
ifconfig egre0 10.0.0.2/24 mtu 1400
ifconfig egre0 up

Greetings,
Arne