Wireguard switcher

wg-switcher.sh

#!/usr/bin/env bash
#
# Switch between Wireguard tunnels located in /etc/wireguard/
# Each tunnel should be defined with a config file, eg. wg0.conf
#
# N. P. O'Donnell, 2022

if [[ $# -ne 1 ]]; then
    echo "Usage: $0 [OPTIONS] [<new tunnel>]"
    echo
    echo "Options:"
    echo " -l: list available tunnels and show active tunnel"
    echo " -s: stop running tunnel"
    exit 1
fi

old_vpn=$(sudo wg | head -n1 | cut -d" " -f2)

if [[ $1 = "-l" ]]; then
    sudo ls -1 /etc/wireguard/*.conf | sed "s/.*\/\([^\/]*\).conf/\1/"
    echo -n "Active: "
    if [[ -n $old_vpn ]]; then
        echo $old_vpn
    else
        echo "<none>"
    fi
    exit 0
fi

if [[ $1 = "-s" ]]; then
    sudo systemctl stop wg-quick@$old_vpn
    exit 0
fi

new_vpn=$1

if [[ -z $(sudo ls -1 /etc/wireguard | grep $new_vpn.conf) ]]; then
    echo "No such VPN: $new_vpn"
    exit 1
fi

# Start new VPN before stopping the old one so there's no downtime.
sudo systemctl enable wg-quick@$new_vpn
sudo systemctl start wg-quick@$new_vpn

if [[ -n $old_vpn ]]; then
    sudo systemctl stop wg-quick@$old_vpn
    sudo systemctl disable wg-quick@$old_vpn
fi