New upstream version 3.1.1

scripts/n2n-gateway.sh

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+#!/bin/bash
+#
+# This is a sample script to route all the host traffic towards a remote
+# gateway, which is reacheable via the n2n virtual interface.
+#
+# This assumes the n2n connection is already been established and the
+# VPN gateway can be pinged by this host.
+#
+
+#######################################################
+# CONFIG
+#######################################################
+
+# The IP address of the gateway through the n2n interface
+N2N_GATEWAY="192.168.100.1"
+
+# The IP address of the supernode as configured in n2n
+N2N_SUPERNODE="1.2.3.4"
+
+# The n2n interface name
+N2N_INTERFACE="n2n0"
+
+# The DNS server to use. Must be a public DNS or a DNS located on the
+# N2N virtual network, otherwise DNS query information will be leaked
+# outside the VPN.
+DNS_SERVER="8.8.8.8"
+
+#######################################################
+# END CONFIG
+#######################################################
+
+if [[ $UID -ne 0 ]]; then
+  echo "This script must be run as root"
+  exit 1
+fi
+
+if ! ip route get $N2N_GATEWAY | grep -q $N2N_INTERFACE ; then
+  echo "Cannot reach the gateway ($N2N_GATEWAY) via $N2N_INTERFACE. Is edge running?"
+  exit 1
+fi
+
+# Determine the current internet gateway
+internet_gateway=$(ip route get 8.8.8.8 | head -n1 | awk '{ print $3 }')
+
+# Backup the DNS resolver configuration and use the specified server
+cp /etc/resolv.conf /etc/resolv.conf.my_bak
+echo "Using DNS server $DNS_SERVER"
+echo "nameserver $DNS_SERVER" > /etc/resolv.conf
+
+# The public IP of the supernode must be reachable via the internet gateway
+# Whereas all the other traffic will go through the new VPN gateway.
+ip route add $N2N_SUPERNODE via "$internet_gateway"
+ip route del default
+echo "Forwarding traffic via $N2N_GATEWAY"
+ip route add default via $N2N_GATEWAY
+
+function stopService {
+  echo "Deleting custom routes"
+  ip route del default
+  ip route del $N2N_SUPERNODE via "$internet_gateway"
+
+  echo "Restoring original gateway $internet_gateway"
+  ip route add default via "$internet_gateway"
+
+  echo "Restoring original DNS"
+  mv /etc/resolv.conf.my_bak /etc/resolv.conf
+
+  exit 0
+}
+
+# setup signal handlers
+trap "stopService" SIGHUP SIGINT SIGTERM
+
+# enter wait loop
+echo "VPN is now up"
+while :; do sleep 300; done