Test: OpenBSD UDP Server: # ifconfig tun0 create # ifconfig tun0 inet 192.168.74.1/24 # socat -d -d UDP-LISTEN:11443,reuseaddr GOPEN:/dev/tun0 2023/11/13 10:30:58 socat[31554] N listening on UDP LEN=16 AF=2 0.0.0.0:11443 2023/11/13 10:33:27 socat[31554] N accepting UDP connection from LEN=16 AF=2 192.168.255.2:59152 2023/11/13 10:33:27 socat[31554] N opening character device "/dev/tun0" for reading and writing
Linux UDP Client: $ socat UDP:1.2.3.4:11443 TUN:192.168.74.2/24,up OpenBSD UDP Server, this line appears: 2023/11/13 10:33:27 socat[31554] N starting data transfer loop with FDs [5,5] and [6,6] Linux UDP Client, start a ping but no replies received $ ping 192.168.74.1 OpenBSD UDP Server, tcpdump -ni tun0 shows: 11:02:15.130291 11:02:16.130410 11:02:17.130223 11:02:18.130072 11:02:19.131211 11:02:20.130417 11:02:21.130218 So, maybe socat doesn't know how to decode raw data received on tun0. Thanks anyway Il giorno dom 12 nov 2023 alle ore 14:03 Sebastien Marie < sema...@kapouay.eu.org> ha scritto: > Luca Di Gregorio <luc...@gmail.com> writes: > > > So, I installed socat with pkg_add and tried to do like this: > > http://www.dest-unreach.org/socat/doc/socat-tun.html > > > > Anyway, I see this: > > # socat UDP:1.2.3.4:11443 TUN:192.168.255.2/24,up > > 2023/11/11 14:11:27 socat[4504] E unknown device/address "TUN" > > > > Have you try to manually configure tun(4) interface and simply use > /dev/tun0 ? > > To keep your example: > # ifconfig tun0 create > # ifconfig tun0 inet 192.168.255.2/24 > # socat UDP:1.2.3.4:11443 GOPEN:/dev/tun0 > > Regards. > -- > Sebastien Marie >
