addroutes

#!/bin/bash

progname=$( $(which basename) $0)

if [ $# -eq 0 ]
then
	/bin/echo "usage: ${progname} <file> [ <file> ... ]" >&2
	exit 1
fi

for hostfile in "$@"
do
	if [ ! -e "${hostfile}" ]
	then
		/bin/echo "Error: ${hostfile}: no such file or directory"
		exit 2
	elif [ ! -f "${hostfile}" ]
	then
		/bin/echo "Error: ${hostfile}: not a file"
		exit 2
	elif [ ! -r "${hostfile}" ]
	then
		/bin/echo "Error: ${hostfile}: permission denied"
		exit 2
	elif [ ! -s "${hostfile}" ]
	then
		/bin/echo "Error: ${hostfile}: empty file"
		exit 2
	fi
done

for hostfile in "$@"
do
	/bin/echo "Adding default routes to hosts listed in ${hostfile} ..."

	ifconfig_out="/tmp/ifconfig-out-$(/usr/bin/uuidgen).txt"
	/sbin/ifconfig -a > "${ifconfig_out}"

	interfaces=($(/bin/egrep -v "^[[:space:]]" "${ifconfig_out}" | /bin/egrep -v "^$" | /usr/bin/cut -d' ' -f 1))
	/bin/echo "Please select from the following interfaces:"

	for i in "${!interfaces[@]}"
	do
		interface=${interfaces[${i}]}
		string=$(/bin/egrep -A 1 "^${interface}" "${ifconfig_out}" | /usr/bin/tr '\n' ' ')

		# Get the link encapsulation
		encaps[${i}]=$(/bin/echo "${string}" | /bin/sed -e 's/^.*encap://' | /bin/sed -e 's/[[:space:]]\{2,\}.*$//')

		# Get the MAC address
		macs[${i}]=$(/bin/echo "${string}" | /usr/bin/awk '{for (i = 1; i <= NF; i++) {if ($i == "HWaddr") print $(i + 1)}}')

		# Get the IP address
		ipaddrs[${i}]=$(/bin/echo "${string}" | /bin/sed -e 's/^.*inet addr://' | /bin/sed -e 's/[[:space:]].*$//')

		/usr/bin/printf "%2s) %s (encapsulation %s, IP address %s" "${i}" "${interfaces[${i}]}" "${encaps[${i}]}" "${ipaddrs[${i}]}"
		if [[ -n "${macs[${i}]}" ]]
		then
			/usr/bin/printf ", MAC address %s" "${macs[${i}]}"
		fi
		/usr/bin/printf ")\n"
	done
	rm -f ${ifconfig_out}

	/bin/echo ""
	while true
	do
		/bin/echo -n "Selection: "
		read choice
		if [[ "${choice}" =~ ^[0-9]+$ ]]
		then
			if test "${interfaces[${choice}]+isset}"
			then
				break
			fi
		fi
		/bin/echo "\"${choice}\" is not a valid selection."
	done

	# Get the gateway address
	/bin/echo "Ascertaining the gateway for network device ${interfaces[${choice}]} ..."
	gateway=$(/sbin/route | /bin/egrep "^default" | /bin/egrep "${interfaces[${choice}]}" | awk '{print $2}')
	if [ -n "${gateway}" ]
	then
		/bin/echo "Found gateway: ${gateway}"
	elif [ -n "${ipaddrs[${choice}]}" ]
	then
		/bin/echo "No gateway found, but IP address present."
		/bin/echo "Using IP address as gateway ..."
		gateway="${ipaddrs[${choice}]}"
	else
		/bin/echo "Error: No gateway found for network device ${interfaces[${choice}]}"
		exit 2
	fi

	nfields=0
	line=0
	correct=2
	while read remotehost
	do
		line=$((${line} + 1))
		remotehost2=$(/bin/echo "${remotehost}" | sed -e 's/#.*$//g')
		echo "${remotehost2}"
		nfields=$(/bin/echo "${remotehost2}" | awk '{print NF}')
		if [ "${nfields}" -eq 0 ]
		then
			continue
		elif [ "${nfields}" -ne "${correct}" ]
		then
			/bin/echo "Error on line ${line} of ${hostfile}: Incorrect number of fields (expected: ${correct})"
			/bin/echo "Text: ${remotehost}"
			continue
		else
			host=$(/bin/echo "${remotehost2}" | awk '{print $1}')
			netmask=$(/bin/echo "${remotehost2}" | awk '{print $2}')
			if [ "${netmask}" == "255.255.255.255" ]
			then
				/bin/echo "Adding remote host ${host} ..."
				/usr/bin/sudo /sbin/route del -host "${host}"
				/usr/bin/sudo /sbin/route add -host "${host}" gw "${gateway}" dev "${interfaces[${choice}]}"
			else
				/bin/echo "Adding remote network ${host} with netmask ${netmask} ..."
				/usr/bin/sudo /sbin/route del -net "${host}" netmask "${netmask}"
				/usr/bin/sudo /sbin/route add -net "${host}" netmask "${netmask}" gw "${gateway}" dev "${interfaces[${choice}]}"
			fi
		fi
	done < ${hostfile}
	/bin/echo "Finished with hosts listed in file ${hostfile}"
done
/bin/echo "Done"