[Acio]

Fixes #2169

getConnectionInterface() read a fixed column ($5) of ip -o route get 1.1.1.1. The column layout of that output varies:

route	output	$5
via gateway	1.1.1.1 via 192.168.40.1 dev wlan0 src ...	wlan0 ✔
wg-quick full tunnel	1.1.1.1 dev wg0 table 51820 src ...	51820 ✘
no gateway (e.g. PPP)	1.1.1.1 dev ppp0 src 10.64.1.2 ...	10.64.1.2 ✘

This change:

• takes the interface from the dev field instead of a fixed column;
• when that interface is a VPN (wg0, tun0, tailscale0, the same list Sysinfo::getActiveVpnInterface() uses), returns the physical uplink from the main table's default route instead, so the dashboard keeps showing how the device is actually connected; the VPN is already shown separately by the VPN status item.

Testing

On a Pi 5 with RaspAP 3.5.8:

• No VPN: wlan0 / wireless / IP and SSID shown, same as before.
• wg-quick full tunnel (routing recreated in a network namespace: default dev wg0 table 51820, ip rule not fwmark 0xca6c table 51820, ip rule table main suppress_prefixlength 0):
  • before: interface 51820, type other (51820), no IP
  • after: interface wlan0, type wireless, IP 192.168.40.213
• Parsing checked for via / no-via / table variants.

[billz]

@Acio thanks for the PR. parsing the dev field is the right fix for the $5 column assumption. a couple of observations:

1. the VPN interface list now lives here and in Sysinfo::getActiveVpnInterface(). Would you mind moving it to a shared constant or helper so the two don't drift?
2. Probably worth a note in the docblock that the first (lowest metric) default route is used when there are several?

[Acio]

Hi Bill, Thanks for the review! Both points are addressed in 048defd:

1. The VPN interface list is now a single Sysinfo::VPN_INTERFACES constant, used by both Sysinfo::getActiveVpnInterface() and Dashboard::getConnectionInterface(). I left Dashboard::getVpnManaged() as is, since it maps each interface to its management page rather than listing them.
2. The docblock now notes that the first default route of the main table is used when there are several. ip lists them by ascending metric (checked with routes added in the order 700/50/300; they come back as 50/300/700), so that's the route the kernel prefers.

Re-tested on a Pi 5 through includes/autoload.php, with a live wg-quick full tunnel and in a network namespace with the same policy routing: uplink wlan0 / wireless, VPN wg0.

I also will open a feature request for showing when multiple VPNs are connected, instead of just giving back one. I have multiple VPNs open for different routes when away, and just showing the lowest id while factually correct, is not the total picture :)