Wireguard & OpenWRT

Goal: setup my Android handset so that it can connect remotely to hosts on my home network

Follow the OpenWRT Wiki guide for general Wireguard setup.

Addressing

My handset typically doesn’t have IPv6 Internet connectivity, so Wireguard traffic will be over IPv4. However traffic inside the tunnel can be over IPv6.

Name IP
Home IPv6 ULA 1 fd2c:cfce:c1ce::/48
Home WAN IP 203.123.xx.xx
Home LAN IP 192.168.1.1/24, fd2c:cfce:c1ce::1/60
Home WG IP fd2c:cfce:c1ce:10::1/64
Android WAN IP (dynamic IPv4)
Android WG IP fd2c:cfce:c1ce:10::2/64

Wireguard

Android Wireguard config:

[Interface]
Address = fd2c:cfce:c1ce:10::2/64
DNS = fd2c:cfce:c1ce:10::1
PrivateKey = xxxxxxxxxxxxxxxxxxxxxx

[Peer]
AllowedIPs = fd2c:cfce:c1ce::/48
Endpoint = 203.123.xx.xx:51820
PublicKey = f15Cut8SWrguJaPVFp68/N+ior/yJ7q+ml2o/Q+v1zg=

NOTE:

DNS

OpenWRT supports setting hostnames for both IPv4 + IPv6 IP addresses under ‘DHCP and DNS’ -> Hostnames. I have a Truenas server on my home network, so I added 2 entries here:

Hostname IP
truenas 192.168.1.10
truenas6 fd2c:cfce:c1ce:0:12e7:c6ff:fe2f:6412

Each entry corresponds with an A or AAAA record and also a PTR (reverse lookup). I’ve also configured OpenWRT with local domain .lan.

Now I’m able to connect to truenas6.lan from Android.