#!/bin/sh
#
# Update the MPTCP flags with or without the pached iproute2
#
# Author: Mario Krueger <openwrt at xedp3x.de>
#	  Ycarus (Yannick Chabanois) for OpenMPTCProuter <contact@openmptcprouter.com>
# Released under GPL 3 or later

if [ -d "/proc/sys/net/mptcp" ]; then
        if ([ -f /proc/sys/net/mptcp/mptcp_enabled ] && [ `cat /proc/sys/net/mptcp/mptcp_enabled` = 0 ]) || ([ -f /proc/sys/net/mptcp/enabled ] && [ `cat /proc/sys/net/mptcp/enabled` = 0 ]); then
                echo "MPTCP is disabled!"
                exit 1
        fi
else
        echo "Your device don't support multipath-TCP."
        exit 1
fi

case $1 in
   "-h")
        echo "          Multipath-TCP configuration tool"
        echo "show/update flags:"
        echo "  multipath [device]"
        if [ -f /proc/sys/net/mptcp/mptcp_enabled ]; then
                echo "  multipath device {on | off | backup }"
        else
                echo "  multipath device {on | off | signal | backup }"
        fi
        echo
        echo "show established conections: -c"
        echo "show fullmesh info: -f"
        echo "show kernel config: -k"
        echo "show MPTCP info: -m"
        if [ -f /proc/sys/net/mptcp/enabled ]; then
		echo "verify MPTCP interface: -v device"
        fi
        echo
        echo "Flag on the device, to enable/disable MPTCP for this interface. The backup-flag"
        echo "will allow a subflow to be established across this interface, but only be used"
        echo "as backup."
        echo
        exit 0 ;;
   "-c")
        if [ -f /proc/net/mptcp_net/mptcp ]; then
            cat /proc/net/mptcp_net/mptcp
        else
            ss -M
        fi
        exit 0;;
   "-f")
        if [ -f /proc/net/mptcp_fullmesh ]; then
            cat /proc/net/mptcp_fullmesh
        else
            ip mptcp endpoint | grep fullmesh
        fi
        exit 0;;
   "-k")
        if [ -f /proc/sys/net/mptcp/mptcp_enabled ]; then
            echo Enabled: `cat /proc/sys/net/mptcp/mptcp_enabled`
        elif [ -f /proc/sys/net/mptcp/enabled ]; then
            echo Enabled: `cat /proc/sys/net/mptcp/enabled`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_path_manager ]; then
            echo Path Manager: `cat /proc/sys/net/mptcp/mptcp_path_manager`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_checksum ]; then
            echo Use checksum: `cat /proc/sys/net/mptcp/mptcp_checksum`
        elif [ -f /proc/sys/net/mptcp/checksum_enabled ]; then
            echo Use checksum: `cat /proc/sys/net/mptcp/checksum_enabled`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_scheduler ]; then
            echo Scheduler: `cat /proc/sys/net/mptcp/mptcp_scheduler`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_syn_retries ]; then
            echo Syn retries: `cat /proc/sys/net/mptcp/mptcp_syn_retries`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_debug ]; then
            echo Debugmode: `cat /proc/sys/net/mptcp/mptcp_debug`
        fi
        echo
        exit 0 ;;
   "-m")
	if [ -f /proc/net/mptcp_net/snmp ]; then
	    cat /proc/net/mptcp_net/snmp
	else
	    nstat -z | grep -i mptcp
	fi
        exit 0 ;;
   "-v")
	if [ -f /proc/sys/net/mptcp/enabled ]; then
		DEVICE="$2"
		endpoint="$(ip mptcp endpoint show)"
		if [ -f /usr/bin/jsonfilter ]; then
			IP=$(ip -j a show $DEVICE scope global | jsonfilter -e '@[0].addr_info[*].local')
		elif [ -f /usr/bin/jq ]; then
			IP=$(ip -j a show $DEVICE scope global  | jq -r '.[0].addr_info[].local')
		else
			echo "jsonfilter or jq are required"
			exit 1
		fi
        if [ -n "$IP" ] && [ -n "$endpoint" ]; then
            for i in $IP; do
                ID=$(echo "${endpoint}" | grep -F "$i " | awk '{print $3}')
                [ -n "$ID" ] && break
            done
        fi
	fi
	if [ -n "$ID" ]; then
		echo "OK"
		exit 0
	else
		echo "NOK"
		exit 1
	fi
	;;
   "")
        for ifpath in /sys/class/net/*; do
                $0 ${ifpath##*/}
        done
        exit 0;;
   *);;
esac

DEVICE="$1"
TYPE="$2"
#FLAG_PATH=`find /sys/devices/ -path "*/net/$DEVICE/flags"`

[ -e "/sys/class/net/$DEVICE/" ] || {
        #echo "Device '$DEVICE' can't found!"
        #echo "Use the hardware name like in ifconfig"
        exit 1
}

if [ -f /proc/sys/net/mptcp/mptcp_enabled ]; then
        FLAG_PATH="/sys/class/net/$DEVICE/flags"
        IFF=`cat $FLAG_PATH`

        IFF_OFF="0x80000"
        IFF_ON="0x00"
        IFF_BACKUP="0x100000"
        IFF_HANDOVER="0x200000"
        IFF_MASK="0x380000"

        case $TYPE in
                "off")          FLAG=$IFF_OFF;;
                "on")           FLAG=$IFF_ON;;
                "backup")       FLAG=$IFF_BACKUP;;
                "handover")     FLAG=$IFF_HANDOVER;;
                "")
                        IFF=`printf "0x%02x" $(($IFF&$IFF_MASK))`
                        case "$IFF" in
                                $IFF_OFF)       echo $DEVICE is deactivated;;
                                $IFF_ON)        echo $DEVICE is in default mode;;
                                $IFF_BACKUP)    echo $DEVICE is in backup mode;;
                                $IFF_HANDOVER)  echo $DEVICE is in handover mode;;
                                *) echo "Unkown state!" && exit 1;;
                        esac
                        exit 0;;
                *) echo "Unkown flag! Use 'multipath -h' for help" && exit 1;;
        esac

        printf "0x%02x" $(($(($IFF^$(($IFF&$IFF_MASK))))|$FLAG)) > $FLAG_PATH
else
	endpoint="$(ip mptcp endpoint show)"
	if [ -n "$TYPE" ]; then
		# Remove not needed if* interfaces in MPTCP
		[ -n "$endpoint" ] && oldids=$(echo "${endpoint}" | grep "dev if" | awk '{ print $3 }')
		[ -n "$oldids" ] && {
			for oldid in $oldids; do
				ip mptcp endpoint delete id $oldid >/dev/null 2>&1
			done
			endpoint="$(ip mptcp endpoint show)"
		}
	fi
	if [ -n "$endpoint" ]; then
        ID=$(echo "${endpoint}" | sort | grep -F "dev $DEVICE " | awk '{print $3}')
        IFF=$(echo "${endpoint}" | sort | grep -F -m 1 "dev $DEVICE " | awk '{print $4; exit}')
        IFF2=$(echo "${endpoint}" | sort | grep -F -m 1 "dev $DEVICE " | awk '{print $5; exit}')
	fi
	if [ -n "$TYPE" ]; then
		#IP=$(ip a show $DEVICE | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p')
		if [ -f /usr/bin/jsonfilter ]; then
			IP=$(ip -j a show $DEVICE scope global | jsonfilter -e '@[0].addr_info[*].local')
		elif [ -f /usr/bin/jq ]; then
			IP=$(ip -j a show $DEVICE scope global  | jq -r '.[0].addr_info[].local')
		else
			echo "jsonfilter or jq are required"
			exit 1
		fi
        if [ -z "$ID" ] && [ -n "$IP" ] && [ -n "$endpoint" ]; then
            for i in $IP; do
                ID=$(echo "${endpoint}" | grep -F "$i " | awk '{print $3}')
                [ -n "$ID" ] && break
            done
        fi
		[ -n "$endpoint" ] && RMID=$(echo "${endpoint}" | grep '::ffff' | awk '{ print $3 }')
		[ -n "$RMID" ] && ip mptcp endpoint delete id $RMID >/dev/null 2>&1
	fi
	case $TYPE in
                "off")
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i >/dev/null 2>&1
                            done
                        }
                        exit 0;;
                "on")
                        [ -z "$IP" ] && {
                            echo "No global IP found on $DEVICE"
                            exit 1
                        }
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i >/dev/null 2>&1
                            done
                        }
                        for i in $IP; do
                            ip mptcp endpoint add $i dev $DEVICE subflow fullmesh
                        done
                        exit 0;;
                "signal")
                        [ -z "$IP" ] && {
                            echo "No global IP found on $DEVICE"
                            exit 1
                        }
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i >/dev/null 2>&1
                            done
                        }
                        for i in $IP; do
                            #ip mptcp endpoint add $i dev $DEVICE signal subflow fullmesh
                            ip mptcp endpoint add $i dev $DEVICE signal
                        done
                        exit 0;;
                "backup")
                        [ -z "$IP" ] && {
                            echo "No global IP found on $DEVICE"
                            exit 1
                        }
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i >/dev/null 2>&1
                            done
                        }
                        for i in $IP; do
                            ip mptcp endpoint add $i dev $DEVICE subflow backup fullmesh
                        done
                        exit 0;;
                "")
                        case "$IFF" in
                                "")          echo $DEVICE is deactivated;;
                                "subflow")
                                    case "$IFF2" in
                                        "backup")    echo $DEVICE is in backup mode;;
                                        "fullmesh")  echo $DEVICE is in default mode;;
                                        "")  echo $DEVICE is in subflow mode;;
                                    esac
                                    ;;
                                "signal")    echo $DEVICE is in signal mode;;
                                *)           echo "$DEVICE Unkown state!" && exit 1;;
                        esac
                        exit 0;;
                *) echo "Unkown flag! Use 'multipath -h' for help" && exit 1;;
        esac

fi