OpenBSD

Tips, Trick, Notes and Snippets around OpenBSD

Get Interfaces

ifconfig | awk '/^[^\t]/{iface=$1} /inet6? / {print iface, $2}'

lo0: ::1
lo0: fe80::1%lo0
lo0: 127.0.0.1
vio0: fe80::9400:2ff:fe16:5a70%vio0
vio0: 2a01:4f8:c0c:fff7::2
vio0: 159.69.214.12

Adding Static Default GW

man route

route add -inet  default 192.168.1.1
route add -inet6 default 2001:db8:efef::1

Use Puffy as Jumphost

Redirect incomming Traffic from a certain Source and also NAT the Outgoing Traffic so we remain in the “Line” ;)

# Apply SNAT for outgoing Traffic
match out log       on em0    inet            from !(egress)        to IP_OF_TARGET_HOST  nat-to (egress)

# Forward Port 22 to another (hidden) Host via DNAT
pass  in  log quick on egress inet  proto tcp from SRC_IP_OF_HOST   to egress port 22    rdr-to IP_OF_TARGET_HOST   port 22
pass  in  log quick on egress inet  proto tcp from SRC_NET/MASK     to egress port 22    rdr-to IP_OF_TARGET_HOST   port 22

Debug OpenSMTPD

doas rcctl stop smtpd
doas smtpd -dv -Tall

tty0 to fb0 on ARM

you may need to redirect tty0 on arm64 boxes