/lib/mwan3/mwan3.sh for non-IPv6 devices running LEDE 17

mwan3.sh

#!/bin/sh

IP4="/usr/bin/ip -4"
IPS="/usr/sbin/ipset"
IPT4="/usr/sbin/iptables -t mangle -w"
LOG="/usr/bin/logger -t mwan3 -p"

MWAN3_STATUS_DIR="/var/run/mwan3"

[ -d $MWAN3_STATUS_DIR ] || mkdir -p $MWAN3_STATUS_DIR/iface_state

mwan3_lock() {
	lock /var/run/mwan3.lock
}

mwan3_unlock() {
	lock -u /var/run/mwan3.lock
}

mwan3_lock_clean() {
	rm -rf /var/run/mwan3.lock
}

mwan3_get_iface_id()
{
	local _tmp _iface _iface_count

	_iface="$2"

	mwan3_get_id()
	{
		let _iface_count++
		[ "$1" == "$_iface" ] && _tmp=$_iface_count
	}
	config_foreach mwan3_get_id interface
	export "$1=$_tmp"
}

mwan3_set_connected_iptables()
{
	local connected_network_v4

	$IPS -! create mwan3_connected_v4 hash:net
	$IPS create mwan3_connected_v4_temp hash:net

	for connected_network_v4 in $($IP4 route | awk '{print $1}' | egrep '[0-9]{1,3}(\.[0-9]{1,3}){3}'); do
		$IPS -! add mwan3_connected_v4_temp $connected_network_v4
	done

	for connected_network_v4 in $($IP4 route list table 0 | awk '{print $2}' | egrep '[0-9]{1,3}(\.[0-9]{1,3}){3}'); do
		$IPS -! add mwan3_connected_v4_temp $connected_network_v4
	done

	$IPS add mwan3_connected_v4_temp 224.0.0.0/3

	$IPS swap mwan3_connected_v4_temp mwan3_connected_v4
	$IPS destroy mwan3_connected_v4_temp

	$IPS -! create mwan3_connected list:set
	$IPS -! add mwan3_connected mwan3_connected_v4
}

mwan3_set_general_rules()
{
	local IP

	for IP in "$IP4"; do

		if [ -z "$($IP rule list | awk '$1 == "2253:"')" ]; then
			$IP rule add pref 2253 fwmark 0xfd00/0xff00 blackhole
		fi

		if [ -z "$($IP rule list | awk '$1 == "2254:"')" ]; then
			$IP rule add pref 2254 fwmark 0xfe00/0xff00 unreachable
		fi
	done
}

mwan3_set_general_iptables()
{
	local IPT

	for IPT in "$IPT4"; do

		if ! $IPT -S mwan3_ifaces_in &> /dev/null; then
			$IPT -N mwan3_ifaces_in
		fi

		if ! $IPT -S mwan3_connected &> /dev/null; then
			$IPT -N mwan3_connected
			$IPS -! create mwan3_connected list:set
			$IPT -A mwan3_connected -m set --match-set mwan3_connected dst -j MARK --set-xmark 0xff00/0xff00
		fi

		if ! $IPT -S mwan3_ifaces_out &> /dev/null; then
			$IPT -N mwan3_ifaces_out
		fi

		if ! $IPT -S mwan3_rules &> /dev/null; then
			$IPT -N mwan3_rules
		fi

		if ! $IPT -S mwan3_hook &> /dev/null; then
			$IPT -N mwan3_hook
			$IPT -A mwan3_hook -j CONNMARK --restore-mark --nfmask 0xff00 --ctmask 0xff00
			$IPT -A mwan3_hook -m mark --mark 0x0/0xff00 -j mwan3_ifaces_in
			$IPT -A mwan3_hook -m mark --mark 0x0/0xff00 -j mwan3_connected
			$IPT -A mwan3_hook -m mark --mark 0x0/0xff00 -j mwan3_ifaces_out
			$IPT -A mwan3_hook -m mark --mark 0x0/0xff00 -j mwan3_rules
			$IPT -A mwan3_hook -j CONNMARK --save-mark --nfmask 0xff00 --ctmask 0xff00
			$IPT -A mwan3_hook -m mark ! --mark 0xff00/0xff00 -j mwan3_connected
		fi

		if ! $IPT -S PREROUTING | grep mwan3_hook &> /dev/null; then
			$IPT -A PREROUTING -j mwan3_hook
		fi

		if ! $IPT -S OUTPUT | grep mwan3_hook &> /dev/null; then
			$IPT -A OUTPUT -j mwan3_hook
		fi
	done
}

mwan3_create_iface_iptables()
{
	local id family src_ip

	config_get family $1 family ipv4
	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	if [ "$family" == "ipv4" ]; then

		network_get_ipaddr src_ip $1

		$IPS -! create mwan3_connected list:set

		if ! $IPT4 -S mwan3_ifaces_in &> /dev/null; then
			$IPT4 -N mwan3_ifaces_in
		fi

		if ! $IPT4 -S mwan3_ifaces_out &> /dev/null; then
			$IPT4 -N mwan3_ifaces_out
		fi

		if ! $IPT4 -S mwan3_iface_in_$1 &> /dev/null; then
			$IPT4 -N mwan3_iface_in_$1
		fi

		if ! $IPT4 -S mwan3_iface_out_$1 &> /dev/null; then
			$IPT4 -N mwan3_iface_out_$1
		fi

		$IPT4 -F mwan3_iface_in_$1
		$IPT4 -A mwan3_iface_in_$1 -i $2 -m set --match-set mwan3_connected src -m mark --mark 0x0/0xff00 -m comment --comment "default" -j MARK --set-xmark 0xff00/0xff00
		$IPT4 -A mwan3_iface_in_$1 -i $2 -m mark --mark 0x0/0xff00 -m comment --comment "$1" -j MARK --set-xmark $(($id*256))/0xff00

		$IPT4 -D mwan3_ifaces_in -m mark --mark 0x0/0xff00 -j mwan3_iface_in_$1 &> /dev/null
		$IPT4 -A mwan3_ifaces_in -m mark --mark 0x0/0xff00 -j mwan3_iface_in_$1

		$IPT4 -F mwan3_iface_out_$1
		$IPT4 -A mwan3_iface_out_$1 -s $src_ip -m mark --mark 0x0/0xff00 -m comment --comment "$1" -j MARK --set-xmark $(($id*256))/0xff00

		$IPT4 -D mwan3_ifaces_out -m mark --mark 0x0/0xff00 -j mwan3_iface_out_$1 &> /dev/null
		$IPT4 -A mwan3_ifaces_out -m mark --mark 0x0/0xff00 -j mwan3_iface_out_$1
	fi
}

mwan3_delete_iface_iptables()
{
	config_get family $1 family ipv4

	if [ "$family" == "ipv4" ]; then

		$IPT4 -D mwan3_ifaces_in -m mark --mark 0x0/0xff00 -j mwan3_iface_in_$1 &> /dev/null
		$IPT4 -F mwan3_iface_in_$1 &> /dev/null
		$IPT4 -X mwan3_iface_in_$1 &> /dev/null

		$IPT4 -D mwan3_ifaces_out -m mark --mark 0x0/0xff00 -j mwan3_iface_out_$1 &> /dev/null
		$IPT4 -F mwan3_iface_out_$1 &> /dev/null
		$IPT4 -X mwan3_iface_out_$1 &> /dev/null
	fi
}

mwan3_create_iface_route()
{
	local id route_args

	config_get family $1 family ipv4
	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	if [ "$family" == "ipv4" ]; then

		network_get_gateway route_args $1
		route_args="via $route_args dev $2"

		$IP4 route flush table $id
		$IP4 route add table $id default $route_args
	fi

}

mwan3_delete_iface_route()
{
	local id

	config_get family $1 family ipv4
	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	if [ "$family" == "ipv4" ]; then
		$IP4 route flush table $id
	fi

}

mwan3_create_iface_rules()
{
	local id family

	config_get family $1 family ipv4
	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	if [ "$family" == "ipv4" ]; then

		while [ -n "$($IP4 rule list | awk '$1 == "'$(($id+1000)):'"')" ]; do
			$IP4 rule del pref $(($id+1000))
		done

		while [ -n "$($IP4 rule list | awk '$1 == "'$(($id+2000)):'"')" ]; do
			$IP4 rule del pref $(($id+2000))
		done

		$IP4 rule add pref $(($id+1000)) iif $2 lookup main
		$IP4 rule add pref $(($id+2000)) fwmark $(($id*256))/0xff00 lookup $id
	fi

}

mwan3_delete_iface_rules()
{
	local id family

	config_get family $1 family ipv4
	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	if [ "$family" == "ipv4" ]; then

		while [ -n "$($IP4 rule list | awk '$1 == "'$(($id+1000)):'"')" ]; do
			$IP4 rule del pref $(($id+1000))
		done

		while [ -n "$($IP4 rule list | awk '$1 == "'$(($id+2000)):'"')" ]; do
			$IP4 rule del pref $(($id+2000))
		done
	fi

}

mwan3_delete_iface_ipset_entries()
{
	local id setname entry

	mwan3_get_iface_id id $1

	[ -n "$id" ] || return 0

	for setname in $(ipset -n list | grep ^mwan3_sticky_); do
		for entry in $(ipset list $setname | grep "$(echo $(($id*256)) | awk '{ printf "0x%08x", $1; }')" | cut -d ' ' -f 1); do
			$IPS del $setname $entry
		done
	done
}

mwan3_track()
{
	local track_ip track_ips reliability count timeout interval down up

	mwan3_list_track_ips()
	{
		track_ips="$1 $track_ips"
	}
	config_list_foreach $1 track_ip mwan3_list_track_ips

	if [ -e /var/run/mwan3track-$1.pid ] ; then
		kill $(cat /var/run/mwan3track-$1.pid) &> /dev/null
		rm /var/run/mwan3track-$1.pid &> /dev/null
	fi

	if [ -n "$track_ips" ]; then
		config_get reliability $1 reliability 1
		config_get count $1 count 1
		config_get timeout $1 timeout 4
		config_get interval $1 interval 10
		config_get down $1 down 5
		config_get up $1 up 5

		[ -x /usr/sbin/mwan3track ] && /usr/sbin/mwan3track $1 $2 $reliability $count $timeout $interval $down $up $track_ips &
	fi
}

mwan3_set_policy()
{
	local iface_count id iface family metric probability weight

	config_get iface $1 interface
	config_get metric $1 metric 1
	config_get weight $1 weight 1

	[ -n "$iface" ] || return 0

	mwan3_get_iface_id id $iface

	[ -n "$id" ] || return 0

	config_get family $iface family ipv4

	if [ "$family" == "ipv4" ]; then

		if [ "$(mwan3_get_iface_hotplug_state $iface)" = "online" ]; then
			if [ "$metric" -lt "$lowest_metric_v4" ]; then

				total_weight_v4=$weight
				$IPT4 -F mwan3_policy_$policy
				$IPT4 -A mwan3_policy_$policy -m mark --mark 0x0/0xff00 -m comment --comment "$iface $weight $weight" -j MARK --set-xmark $(($id*256))/0xff00

				lowest_metric_v4=$metric

			elif [ "$metric" -eq "$lowest_metric_v4" ]; then

				total_weight_v4=$(($total_weight_v4+$weight))
				probability=$(($weight*1000/$total_weight_v4))

				if [ "$probability" -lt 10 ]; then
					probability="0.00$probability"
				elif [ $probability -lt 100 ]; then
					probability="0.0$probability"
				elif [ $probability -lt 1000 ]; then
					probability="0.$probability"
				else
					probability="1"
				fi

				probability="-m statistic --mode random --probability $probability"

				$IPT4 -I mwan3_policy_$policy -m mark --mark 0x0/0xff00 $probability -m comment --comment "$iface $weight $total_weight_v4" -j MARK --set-xmark $(($id*256))/0xff00
			fi
		fi
	fi
}

mwan3_create_policies_iptables()
{
	local last_resort lowest_metric_v4 total_weight_v4 policy IPT

	policy="$1"

	config_get last_resort $1 last_resort unreachable

	if [ "$1" != $(echo "$1" | cut -c1-15) ]; then
		$LOG warn "Policy $1 exceeds max of 15 chars. Not setting policy" && return 0
	fi

	for IPT in "$IPT4"; do

		if ! $IPT -S mwan3_policy_$1 &> /dev/null; then
			$IPT -N mwan3_policy_$1
		fi

		$IPT -F mwan3_policy_$1

		case "$last_resort" in
			blackhole)
				$IPT -A mwan3_policy_$1 -m mark --mark 0x0/0xff00 -m comment --comment "blackhole" -j MARK --set-xmark 0xfd00/0xff00
			;;
			default)
				$IPT -A mwan3_policy_$1 -m mark --mark 0x0/0xff00 -m comment --comment "default" -j MARK --set-xmark 0xff00/0xff00
			;;
			*)
				$IPT -A mwan3_policy_$1 -m mark --mark 0x0/0xff00 -m comment --comment "unreachable" -j MARK --set-xmark 0xfe00/0xff00
			;;
		esac
	done

	lowest_metric_v4=256
	total_weight_v4=0

	config_list_foreach $1 use_member mwan3_set_policy
}

mwan3_set_policies_iptables()
{
	config_foreach mwan3_create_policies_iptables policy
}

mwan3_set_sticky_iptables()
{
	local id iface

	for iface in $($IPT4 -S $policy | cut -s -d'"' -f2 | awk '{print $1}'); do

		if [ "$iface" == "$1" ]; then

			mwan3_get_iface_id id $1

			[ -n "$id" ] || return 0

			for IPT in "$IPT4"; do
				if [ -n "$($IPT -S mwan3_iface_in_$1 2> /dev/null)" -a -n "$($IPT -S mwan3_iface_out_$1 2> /dev/null)" ]; then
					$IPT -I mwan3_rule_$rule -m mark --mark $(($id*256))/0xff00 -m set ! --match-set mwan3_sticky_$rule src,src -j MARK --set-xmark 0x0/0xff00
					$IPT -I mwan3_rule_$rule -m mark --mark 0/0xff00 -j MARK --set-xmark $(($id*256))/0xff00
				fi
			done
		fi
	done
}

mwan3_set_user_iptables_rule()
{
	local ipset family proto policy src_ip src_port sticky dest_ip dest_port use_policy timeout rule policy IPT

	rule="$1"

	config_get sticky $1 sticky 0
	config_get timeout $1 timeout 600
	config_get ipset $1 ipset
	config_get proto $1 proto all
	config_get src_ip $1 src_ip 0.0.0.0/0
	config_get src_port $1 src_port 0:65535
	config_get dest_ip $1 dest_ip 0.0.0.0/0
	config_get dest_port $1 dest_port 0:65535
	config_get use_policy $1 use_policy
	config_get family $1 family any

	if [ "$1" != $(echo "$1" | cut -c1-15) ]; then
		$LOG warn "Rule $1 exceeds max of 15 chars. Not setting rule" && return 0
	fi

	if [ -n "$ipset" ]; then
		ipset="-m set --match-set $ipset dst"
	fi

	if [ -n "$use_policy" ]; then
		if [ "$use_policy" == "default" ]; then
			policy="MARK --set-xmark 0xff00/0xff00"
		elif [ "$use_policy" == "unreachable" ]; then
			policy="MARK --set-xmark 0xfe00/0xff00"
		elif [ "$use_policy" == "blackhole" ]; then
			policy="MARK --set-xmark 0xfd00/0xff00"
		else
			if [ "$sticky" -eq 1 ]; then

				policy="mwan3_policy_$use_policy"

				for IPT in "$IPT4"; do
					if ! $IPT -S $policy &> /dev/null; then
						$IPT -N $policy
					fi

					if ! $IPT -S mwan3_rule_$1 &> /dev/null; then
						$IPT -N mwan3_rule_$1
					fi

					$IPT -F mwan3_rule_$1
				done

				$IPS -! create mwan3_sticky_v4_$rule hash:ip,mark markmask 0xff00 timeout $timeout
				$IPS -! create mwan3_sticky_$rule list:set
				$IPS -! add mwan3_sticky_$rule mwan3_sticky_v4_$rule

				config_foreach mwan3_set_sticky_iptables interface

				for IPT in "$IPT4"; do
					$IPT -A mwan3_rule_$1 -m mark --mark 0/0xff00 -j $policy
					$IPT -A mwan3_rule_$1 -m mark ! --mark 0xfc00/0xfc00 -j SET --del-set mwan3_sticky_$rule src,src
					$IPT -A mwan3_rule_$1 -m mark ! --mark 0xfc00/0xfc00 -j SET --add-set mwan3_sticky_$rule src,src
				done

				policy="mwan3_rule_$1"
			else
				policy="mwan3_policy_$use_policy"

				for IPT in "$IPT4"; do
					if ! $IPT -S $policy &> /dev/null; then
						$IPT -N $policy
					fi
				done

			fi
		fi

		if [ "$family" == "any" ]; then

			for IPT in "$IPT4"; do
				case $proto in
					tcp|udp)
					$IPT -A mwan3_rules -p $proto -s $src_ip -d $dest_ip $ipset -m multiport --sports $src_port -m multiport --dports $dest_port -m mark --mark 0/0xff00 -m comment --comment "$1" -j $policy &> /dev/null
					;;
					*)
					$IPT -A mwan3_rules -p $proto -s $src_ip -d $dest_ip $ipset -m mark --mark 0/0xff00 -m comment --comment "$1" -j $policy &> /dev/null
					;;
				esac
			done

		elif [ "$family" == "ipv4" ]; then

			case $proto in
				tcp|udp)
				$IPT4 -A mwan3_rules -p $proto -s $src_ip -d $dest_ip $ipset -m multiport --sports $src_port -m multiport --dports $dest_port -m mark --mark 0/0xff00 -m comment --comment "$1" -j $policy &> /dev/null
				;;
				*)
				$IPT4 -A mwan3_rules -p $proto -s $src_ip -d $dest_ip $ipset -m mark --mark 0/0xff00 -m comment --comment "$1" -j $policy &> /dev/null
				;;
			esac
    fi
	fi
}

mwan3_set_user_rules()
{
	local IPT

	for IPT in "$IPT4"; do

		if ! $IPT -S mwan3_rules &> /dev/null; then
			$IPT -N mwan3_rules
		fi

		$IPT -F mwan3_rules
	done

	config_foreach mwan3_set_user_iptables_rule rule
}

mwan3_set_iface_hotplug_state() {
	local iface=$1
	local state=$2

	echo -n $state > $MWAN3_STATUS_DIR/iface_state/$iface
}

mwan3_get_iface_hotplug_state() {
	local iface=$1

	cat $MWAN3_STATUS_DIR/iface_state/$iface 2>/dev/null || echo "unknown"
}

mwan3_report_iface_status()
{
	local device result track_ips tracking IP IPT

	mwan3_get_iface_id id $1
	network_get_device device $1
	config_get enabled "$1" enabled 0
	config_get family "$1" family ipv4

	if [ "$family" == "ipv4" ]; then
		IP="$IP4"
		IPT="$IPT4"
	fi

	if [ -z "$id" -o -z "$device" ]; then
		result="unknown"
	elif [ -n "$($IP rule | awk '$1 == "'$(($id+1000)):'"')" -a -n "$($IP rule | awk '$1 == "'$(($id+2000)):'"')" -a -n "$($IPT -S mwan3_iface_in_$1 2> /dev/null)" -a -n "$($IPT -S mwan3_iface_out_$1 2> /dev/null)" -a -n "$($IP route list table $id default dev $device 2> /dev/null)" ]; then
		result="$(mwan3_get_iface_hotplug_state $1)"
	elif [ -n "$($IP rule | awk '$1 == "'$(($id+1000)):'"')" -o -n "$($IP rule | awk '$1 == "'$(($id+2000)):'"')" -o -n "$($IPT -S mwan3_iface_in_$1 2> /dev/null)" -o -n "$($IPT -S mwan3_iface_out_$1 2> /dev/null)" -o -n "$($IP route list table $id default dev $device 2> /dev/null)" ]; then
		result="error"
	elif [ "$enabled" == "1" ]; then
		result="offline"
	else
		result="disabled"
	fi

	mwan3_list_track_ips()
	{
		track_ips="$1 $track_ips"
	}
	config_list_foreach $1 track_ip mwan3_list_track_ips

	if [ -n "$track_ips" ]; then
		if [ -n "$(ps -w | grep mwan3track | grep -v grep | sed '/.*\/usr\/sbin\/mwan3track \([^ ]*\) .*$/!d;s//\1/' | awk '$1 == "'$1'"')" ]; then
			tracking="active"
		else
			tracking="down"
		fi
	else
		tracking="not enabled"
	fi

	echo " interface $1 is $result and tracking is $tracking"
}

mwan3_report_policies_v4()
{
	local percent policy share total_weight weight iface

	for policy in $($IPT4 -S | awk '{print $2}' | grep mwan3_policy_ | sort -u); do
		echo "$policy:" | sed 's/mwan3_policy_//'

		[ -n "$total_weight" ] || total_weight=$($IPT4 -S $policy | cut -s -d'"' -f2 | head -1 | awk '{print $3}')

		if [ ! -z "${total_weight##*[!0-9]*}" ]; then
			for iface in $($IPT4 -S $policy | cut -s -d'"' -f2 | awk '{print $1}'); do
				weight=$($IPT4 -S $policy | cut -s -d'"' -f2 | awk '$1 == "'$iface'"' | awk '{print $2}')
				percent=$(($weight*100/$total_weight))
				echo " $iface ($percent%)"
			done
		else
			echo " $($IPT4 -S $policy | sed '/.*--comment \([^ ]*\) .*$/!d;s//\1/;q')"
		fi

		unset total_weight

		echo -e
	done
}

mwan3_report_connected_v4()
{
	local address

	if [ -n "$($IPT4 -S mwan3_connected 2> /dev/null)" ]; then
		for address in $($IPS list mwan3_connected_v4 | egrep '[0-9]{1,3}(\.[0-9]{1,3}){3}'); do
			echo " $address"
		done
	fi
}

mwan3_report_rules_v4()
{
	if [ -n "$($IPT4 -S mwan3_rules 2> /dev/null)" ]; then
		$IPT4 -L mwan3_rules -n -v 2> /dev/null | tail -n+3 | sed 's/mark.*//' | sed 's/mwan3_policy_/- /' | sed 's/mwan3_rule_/S /'
	fi
}