From 1aa326e4eec6c1136afdd0ef6baca091a451c482 Mon Sep 17 00:00:00 2001
From: Andris Raugulis <moo@arthepsy.eu>
Date: Mon, 9 Apr 2018 16:46:56 +0300
Subject: [PATCH] Create custom vpnc-script, which handles manual routes and
 dns via unbound.

---
 vpnc-script-wrapper.sh | 99 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100755 vpnc-script-wrapper.sh

diff --git a/vpnc-script-wrapper.sh b/vpnc-script-wrapper.sh
new file mode 100755
index 0000000..1695f42
--- /dev/null
+++ b/vpnc-script-wrapper.sh
@@ -0,0 +1,99 @@
+#!/bin/sh
+
+_VPNC_SCRIPT="/usr/local/sbin/vpnc-script"
+
+_ROUTES="
+10.0.0.0/255.0.0.0/8
+192.168.0.0/255.255.0.0/16
+"
+_DOMAINS="
+example.com
+"
+
+OIFS=$IFS; NLIFS='
+'
+
+_split() {
+	_line=$1; IFS=$2; shift 2
+	read -r -- "$@" <<-EOF
+		${_line}
+	EOF
+}
+
+_get_unbound() {
+        command -v /usr/local/sbin/unbound-control >/dev/null 2>&1 \
+		&& echo "/usr/local/sbin/unbound-control" && return 0
+        command -v unbound-control >/dev/null 2>&1 \
+		&& echo "unbound-control"  && return 0
+        return 1
+}
+
+output_routes()
+{
+	if [ -n "${CISCO_SPLIT_INC}" ]; then
+		_i=0
+		while [ ${_i} -lt ${CISCO_SPLIT_INC} ] ; do
+			eval _addr="\${CISCO_SPLIT_INC_${_i}_ADDR}"
+			eval _mask="\${CISCO_SPLIT_INC_${_i}_MASK}"
+			eval _masklen="\${CISCO_SPLIT_INC_${_i}_MASKLEN}"
+			echo "orig.route: ${_addr}/${_masklen}"
+			_i=$(expr ${_i} + 1)
+		done
+	fi
+}
+
+adjust_routes()
+{
+	for _k in $(env | grep ^CISCO_SPLIT_INC | cut -d '=' -f 1); do
+		unset ${_k}
+	done
+	IFS=$NLIFS
+	_i=0;
+	for _line in ${_ROUTES}; do
+		_split "${_line}" ' ' _route _
+		_split "${_route}" '/' _addr _mask _masklen _
+		export CISCO_SPLIT_INC_${_i}_ADDR="${_addr}"
+		export CISCO_SPLIT_INC_${_i}_MASK="${_mask}"
+		export CISCO_SPLIT_INC_${_i}_MASKLEN="${_masklen}"
+		_i=$(expr ${_i} + 1)
+	done
+	export CISCO_SPLIT_INC=${_i}
+	IFS=$OIFS
+}
+
+output_dns()
+{
+	echo "orig.dns: ${INTERNAL_IP4_DNS}"
+	echo "orig.domain: ${CISCO_DEF_DOMAIN}"
+}
+
+adjust_dns()
+{
+	_dns="${INTERNAL_IP4_DNS}"
+	unset CISCO_DEF_DOMAIN
+	unset INTERNAL_IP4_DNS
+	[ -z "${_dns}" ] && return
+	_unbound=$(_get_unbound) || { echo "err: unbound not found" >&2 && exit 1; }
+	IFS=$NLIFS
+	for _line in ${_DOMAINS}; do
+		_split "${_line}" ' ' _domain _
+		if [ X"${reason}" = X"connect" ]; then
+			${_unbound} forward_add +i "${_domain}" "${_dns}"
+			${_unbound} flush_requestlist
+			${_unbound} flush_zone "${_domain}"
+		elif [ X"${reason}" = X"disconnect" ]; then
+			${_unbound} forward_remove +i "${_domain}" 
+			${_unbound} flush_zone "${_domain}"
+			${_unbound} flush_requestlist 
+		fi
+	done
+	IFS=$OIFS
+}
+
+output_routes
+adjust_routes
+output_dns
+adjust_dns
+
+${_VPNC_SCRIPT} $@
+