#!/bin/sh /etc/rc.common
#
# Copyright Eric Bishop, 2008
# This is free software licensed under the terms of the GNU GPL v2.0
#

START=50

extra_command "show" "Show current Qos configuration (if active)"

include /lib/network
include /usr/lib/gargoyle_firewall_util

config_file_name="qos_gargoyle"
upload_mask="0x007F"
download_mask="0x7F00"
qos_mark_file="/etc/qos_class_marks"

#created while qos is being initialized so hotplug and init script don't
#both try to initialize qos at the same time
lock_file="/var/run/qos_updating"

load_all_config_options()
{
	local config_name="$1"
	local section_id="$2"

	ALL_OPTION_VARIABLES=""
	# this callback loads all the variables
	# in the section_id section when we do
	# config_load. We need to redefine
	# the option_cb for different sections
	# so that the active one isn't still active
	# after we're done with it.  For reference
	# the $1 variable is the name of the option
	# and $2 is the name of the section
	config_cb()
	{
		if [ ."$2" = ."$section_id" ]; then
			option_cb()
			{
				ALL_OPTION_VARIABLES="$ALL_OPTION_VARIABLES $1"
			}
		else
			option_cb() { return 0; }
		fi
	}

	config_load "$config_name"

	for var in $ALL_OPTION_VARIABLES
	do
		config_get "$var" "$section_id" "$var"
	done
}

load_all_config_sections()
{
	local config_name="$1"
	local section_type="$2"

	all_config_sections=""
	section_order=""
	config_cb()
	{
		if [ -n "$2" ] || [ -n "$1" ] ; then
			if [ -n "$section_type" ] ; then
				if [ "$1" = "$section_type" ] ; then
					all_config_sections="$all_config_sections $2"
				fi
			else
				all_config_sections="$all_config_sections $2"
			fi
		fi
	}

	config_load "$config_name"
	echo "$all_config_sections"

}




load_and_sort_all_config_sections()
{
	local config_name="$1"
	local section_type="$2"
	local sort_variable="$3"

	all_config_sections=""
	defined_option_cb()
	{
		if [ "$1" = "$sort_variable" ]; then
			all_config_sections=" $2:$all_config_sections"
		fi
	}

	config_cb()
	{
		if [ -n "$2" ] || [ -n "$1" ] ; then
			if [ -n "$section_type" ] ; then
				if [ "$1" = "$section_type" ] ; then
					all_config_sections="$2 $all_config_sections"
					option_cb() { defined_option_cb $1 $2 ; }
				else
					option_cb() { return 0; }
				fi
			else
				all_config_sections="$2 $all_config_sections"
				option_cb(){ defined_option_cb $1 $2 ; }
			fi
		fi
	}

	config_load "$config_name"

	echo "$all_config_sections" | awk ' {for(i=1; i <= NF; i++){ print $i }}' | sort -n -t ":" | awk 'BEGIN {FS=":"}; {print $2}'
}


get_classname_mark()
{
	local class="$1"
	local class_mark_list="$2"
	echo "$class_mark_list" | awk -v class="$class" '{ for (i = 1; i <= NF; i++){  if($i~class":"){ gsub(class":",""); print $i } }}'
}

apply_all_rules()
{
	local rule_type="$1"
	local class_mark_list="$2"
	local chain="$3"
	local table="$4"

	local need_proto
	local tmp_proto

	# add filter rules
	rule_list=$(load_and_sort_all_config_sections "$config_file_name" "$rule_type" "test_order")
	for rule in $rule_list ; do
		class=""
		proto=""
		min_pkt_size=""
		max_pkt_size=""
		match_str=""
		need_proto=""

		load_all_config_options "$config_file_name" "$rule"

		for option in $ALL_OPTION_VARIABLES ; do

			option_value=$(eval echo \$$option)
			case "$option" in
				source)
					if [ "$3" = "qos_egress" ] ; then
						if [ "$option_value" = "$local_ip" ] || [ "$option_value" = "$wan_ip" ]; then
							option_value="$wan_ip"
						fi
					fi
					match_str="$match_str -s $option_value"
				;;
				destination)
					if [ "$3" = "qos_ingress" ] ; then
						if [ "$option_value" = "$local_ip" ] || [ "$option_value" = "$wan_ip" ]; then
							option_value="$wan_ip"
						fi
					fi
					match_str="$match_str -d $option_value"
				;;
				srcport)
					if [ -n $(echo $option_value | grep "-") ] ; then option_value="$(echo "$option_value" | sed -e 's,-,:,g')" ; fi
					match_str="$match_str --sport $option_value"
					need_proto="1"
				;;
				dstport)
					if [ -n $(echo $option_value | grep "-") ] ; then option_value="$(echo "$option_value" | sed -e 's,-,:,g')" ; fi
					match_str="$match_str --dport $option_value"
					need_proto="1"

				;;
				layer7)
					layer7_connmark=$(cat /etc/l7marker.marks 2>/dev/null | grep "$option_value" | awk '{ print $2 }')
					layer7_mask=$(cat /etc/l7marker.marks 2>/dev/null | grep "$option_value" | awk '{ print $3 }')
					if [ -n "$layer7_connmark" ] ; then
						match_str="$match_str -m connmark --mark $layer7_connmark/$layer7_mask "
					else
						match_str="$match_str -m layer7 --l7proto $option_value"
					fi
				;;
				connbytes_kb)
					match_str="$match_str -m connbytes --connbytes $(($option_value*1024)): --connbytes-dir both --connbytes-mode bytes"
				;;
			esac
		done


		if [ -n "$min_pkt_size" ] || [ -n "$max_pkt_size" ] ; then
			if [ -z "$min_pkt_size" ] ; then min_pkt_size=0 ; fi
			if [ -z "$max_pkt_size" ] ; then max_pkt_size=1500 ; fi
			match_str="$match_str -m length --length $min_pkt_size:$max_pkt_size"
		fi

		if [ -n "$class" ] ; then
			if [ -n "$proto" ] || [ -n "$match_str" ] ; then
				next_mark=$(get_classname_mark "$class" "$class_mark_list" )

				#We need to specify both udp and tcp if the user indicated a port
				#and he did not indiate a protocal.
				if [ -z "$proto" ] && [ -n "$need_proto" ] ; then

					$echo_on
					iptables -t $table -I $chain -p tcp $match_str -j MARK --set-mark $next_mark
					iptables -t $table -I $chain -p udp $match_str -j MARK --set-mark $next_mark
					$echo_off

				else

 					#Otherwise just specify what the user requested (or nothing)

					if [ -n "$proto" ] ; then
						tmp_proto="-p $proto"
					else
						tmp_proto=""
					fi

					$echo_on
					iptables -t $table -I $chain $tmp_proto $match_str -j MARK --set-mark $next_mark
					$echo_off
				fi

			fi
		fi
	done
}


update_markfile()
{

	#initialize mark file in /tmp first, and test md5sum
	#this should speed things up and prevent writing to flash unnecessarily (since /tmp is ramdisk)

	tmp_qos_mark_file="/tmp/qos_marks.tmp.tmp"
	rm -rf "$tmp_qos_mark_file"

	#re-populate per the QoS setup.
	if [ $total_upload_bandwidth -ge 0 ] ; then

		upload_class_list=$(load_all_config_sections "$config_file_name" "upload_class")

		next_class_index=2
		for uclass_name in $upload_class_list ; do
			printf "upload $uclass_name %d $upload_mask\n" $next_class_index >> "$tmp_qos_mark_file"
 			next_class_index=$(($next_class_index+1))
		done
	fi

	if [ $total_download_bandwidth -ge 0 ] ; then

		download_class_list=$(load_all_config_sections "$config_file_name" "download_class")

		next_class_index=2
		for dclass_name in $download_class_list ; do
			printf "download $dclass_name %d $download_mask\n" $(($next_class_index << 8)) >> "$tmp_qos_mark_file"
 			next_class_index=$(($next_class_index+1))
		done
	fi

	mark_files_match="0"
	if [ -e "$qos_mark_file" ] ; then
		new_md5=$(md5sum "$tmp_qos_mark_file" | awk '{ print $1 ; } ')
		old_md5=$(md5sum "$qos_mark_file" | awk '{ print $1 ; } ')
		if [ "$new_md5" = "$old_md5" ] ; then
			mark_files_match="1"
		fi
	fi

	if [ "$mark_files_match" = "0" ] ; then
		mv "$tmp_qos_mark_file" "$qos_mark_file"
	else
		rm -rf "$tmp_qos_mark_file"
	fi

}



initialize_qos()
{
	#initialize layer7_marker if necessary
	create_l7marker_chain

	# Now, load/insert necessary kernel modules
	# The following packages are required for the modules:
	rmmod  imq >&- 2>&-
	insmod imq numdevs=1 hook_chains="INPUT,FORWARD" hook_tables="mangle,mangle" >&- 2>&-
	ip link set dev imq0 mtu 1500

	# Make sure the other kernel modules we need are loaded
	insmod cls_fw >&- 2>&-
	insmod cls_flow >&- 2>&-
	insmod sch_hfsc >&- 2>&-
	insmod sch_sfq >&- 2>&-

	#Deciding how to set sfq_depth is not straight forward. Too high and we burn up RAM
	#needlessly on low memory routers. Too low and our maximum bandwidth gets limited.
	#
	#On low memory routers we need to take it easy on how big the queues can get.
	#When depth is limited to 32 maximum bandwidth through any class will be around 11Mbps.
	#Otherwise it will be around 350Mbps.
	total_mem="$(sed -e '/^MemTotal: /!d; s#MemTotal: *##; s# kB##g' /proc/meminfo)"
	if [ "$total_mem" -lt 16000 ] ; then
		sfq_depth="depth 32";
	else
		sfq_depth="";
	fi

	$echo_off
	#load upload variables
	load_all_config_options "$config_file_name" "upload"
	$echo_on
	if [ -n "$total_bandwidth" ] ; then
		total_upload_bandwidth="$total_bandwidth"
	else
		total_upload_bandwidth=-1
	fi
	upload_default_class="$default_class"

	#load download variables
	total_bandwidth=""
	default_class=""
	$echo_off
	load_all_config_options "$config_file_name" "download"
	$echo_on
	if [ -n "$total_bandwidth" ] ; then
		total_download_bandwidth="$total_bandwidth"
	else
		total_download_bandwidth=-1
	fi
	download_default_class="$default_class"

	#Since the introduction of ADSL IP Extensions its not so easy to tell if we have a DSL connection
	#or not making it hard to set the stab parameters correctly.
	#Stab parameters here are derived from tc-stab(8).html
	overhead="stab linklayer atm overhead 32 mtu 2048 "

	#It is now often difficult to tell if the overhead should be used or not because even DSL modems use DHCP or may
	#not be in bridge mode. So I make the assumption that all connections with less than 3Mbps down or 1Mbps up
	#are DSL regardless of the protocol selection type.
	wan_proto=$(uci get network.wan.proto 2>/dev/null)
	if [ "$wan_proto" != "pppoe" ] && [ "$total_upload_bandwidth" -ge 1100 ] && [ "$total_download_bandwidth" -ge 3100 ] ; then
		overhead=""
	fi

	$echo_off

	if [ $total_upload_bandwidth -ge 0 ] ; then

		#load upload classes
		upload_class_list=$(load_all_config_sections "$config_file_name" "upload_class")
		for uclass_name in $upload_class_list ; do
			percent_bandwidth=""
			min_bandwidth=""
			max_bandwidth=""
			load_all_config_options "$config_file_name" "$uclass_name"
			if [ -z "$percent_bandwidth" ] ; then
				percent_bandwidth="0"
			fi
			if [ -z "$min_bandwidth" ] ; then
				min_bandwidth="-1"
			fi
			if [ -z "$max_bandwidth" ] ; then
				max_bandwidth="-1"
			fi
			classdef="$percent_bandwidth $max_bandwidth $min_bandwidth"
			eval $uclass_name=\"\$classdef\"  #"#comment quote here so formatting in editor isn't FUBAR
		done


		# Attach egress queuing discipline to QoS interface, now with temperary default
		$echo_on
		tc qdisc add dev $qos_interface root handle 1:0 hfsc default 1

		# For the root qdisc, only ul and ls are relevant since rt only applies to leaf qdiscs
		#
		# A detailed explanation of how/why/what is being set is warranted here...
		# Link Share bandwidths of the leaf nodes are all relative to their parents link share parameter and those of their
		# fellow leaf nodes competing for shares. We set the root class link share to 1000Mbit as per unit bandwidth.
		# Leaf nodes are then set with the respective percent of this per unit number.
		#
		# The actual maximum link speed is the lower of the ul and the ls and this is going to always be the ul parameter in our
		# design.
		#
		# Again, for ls only the ratios matter, the absolute values do not.
		tc class add dev $qos_interface parent 1:0 classid 1:1 hfsc ls rate 1000Mbit ul rate ${total_upload_bandwidth}kbit
		$echo_off

		class_mark_list=""
		upload_shift=0
		next_class_index=2
		next_classid=$(printf "0x%X" $(($next_class_index << $upload_shift)) )
		def_upload_idx=$next_class_index
		def_upload_class=$next_classid

		for uclass_name in $upload_class_list ; do

			class_mark_list="$class_mark_list$uclass_name:$next_classid "

			$echo_on
			uclass_def=$(eval echo "\$$uclass_name")

			#Bandwidth at capacity for this class
			m2=$((  10 * $(echo $uclass_def | awk ' {print $1}' ) ))

			#is there a minimum bandwidth specified in kbps?
			min_bandwidth=$( echo $uclass_def | awk ' {print $3}' )
			if [ "$min_bandwidth" -gt 0 ] ; then
				ll_str=" rt m1 $((2*$min_bandwidth))kbit d 2ms m2 ${min_bandwidth}kbit"
			else
				ll_str=""
			fi

			#is there an upper limit specified in kbps?
			max_bandwidth=$( echo $uclass_def | awk ' {print $2}' )
			if [ "$max_bandwidth" -ge 0 ] ; then
				ul_str=" ul m2 ${max_bandwidth}kbit"
			else
				#Calculate from the class link share.
				max_bandwidth=$(($m2*$total_upload_bandwidth/1000000))
				ul_str=""
			fi


			# For leaf nodes in HFSC we calculate the latency as the time spent waiting to earn enough credit (credit_t) to
			#get selected to send plus the time to transmit (tts). The maximum latency can be calculated as shown
			#below assuming an MTU of 1500bytes and 8.2bits/byte including overhead.
			#credit_t = $((1500*82/$max_bandwidth/10));
			#tts = $((1500*82/$total_upload_bandwidth/10));

			#tbw is the Delay x Bandwidth product in bytes. We do not actually know the packet
			#delay so we make an estimate of 150ms here and hope for the best. max_bandwidth is in kbps
			#we multiply 100ms by 1000 below so the units work out.
			tbw=$(($max_bandwidth*100/8));
			if [ "$tbw" -lt 6000 ] ; then
				tbw=6000
			fi

			#We will use the SFQ qdisc with flow classifier.  The limit on the depth of our qdisc depends on the upper limit
			#of the bandwidth allocated to this class.  To impliment per IP sharing of the class we use the flow classifier
			#and the 'nfct-src' on the upload side and 'dst' on the download side.  I found a nice man page here
			#https://arndtroide.homelinux.org/cgi-bin/man/man2html?tc-sfq+8
			
			#Add the leaf class
			tc class add dev $qos_interface parent 1:1 classid 1:$next_class_index hfsc ls m2 ${m2}Mbit $ll_str $ul_str
			#Add the qdisc to the leaf class, assuming average packet at 250 bytes.
			tc qdisc add dev $qos_interface parent 1:$next_class_index handle $next_class_index:1 sfq headdrop limit $(($tbw/250)) $sfq_depth divisor 256

			#
			#Folks interested in experimenting with CoDEL can comment out the preceeding line and uncomment hte next line.
			#This will work for the upload direction. Left to the student how to mod the download.
			#As of Chaos Calmer there does not seem to be any benefit in changing SFQ to FQ_CODEL and some stability
			#issues as well. Will re-evaluate once Openwrt 18.06 based Gargoyle is released.
			#fq_codel parameters
			#	limit - SFQ used 127 so i suggest the same here.
			#	target - At and above 6Mbps = 5ms (min). At 100kbps = 100ms (max). Select accordingly
			#	interval - 100ms, This is the default
			#	flows - 255 (One for each IP)
			#
			#tc qdisc add dev $qos_interface parent 1:$next_class_index handle $next_class_index:1 fq_codel limit 127 target 5ms interval 100ms flows 255 quantum 1514

			#Add a filter to the root class to direct packets to this leaf class according to the conntrack mark
			tc filter add dev $qos_interface parent 1:0 protocol ip handle $next_classid fw flowid 1:$next_class_index
			#Add a filter to the leaf class to define flows as being the source IP address.
			tc filter add dev $qos_interface parent $next_class_index: handle 1 flow divisor 256 map key nfct-src and 0xff
			$echo_off

			if [ "$upload_default_class" = "$uclass_name" ] ; then
				def_upload_idx=$next_class_index
				def_upload_class=$next_classid
			fi

			next_class_index=$(($next_class_index+1))
			next_classid=$(printf "0x%X" $(($next_class_index << $upload_shift)) )
		done

		$echo_on

		#Go back and touch up the root qdisc to have the proper default class
		tc qdisc change dev $qos_interface $overhead root handle 1:0 hfsc default $def_upload_idx

		# Set up egress chain
		iptables -t mangle -N qos_egress
		iptables -t mangle -A POSTROUTING -o $qos_interface -j qos_egress

		#Next the user entered rules.
		$echo_off
		apply_all_rules "upload_rule" "$class_mark_list" "qos_egress" "mangle"
		$echo_on

		#set default class mark first in case we don't match anything
		iptables -t mangle -I qos_egress -j MARK --set-mark $def_upload_class

		#if we already set a mark in quota chain, we need to save that mark to the connmark, then return so it doesn't get over-written
		iptables -t mangle -I qos_egress -m mark ! --mark 0x0 -j RETURN
		iptables -t mangle -I qos_egress -m mark ! --mark 0x0 -j CONNMARK --save-mark --mask $upload_mask

		# save current mark to connmark at end of chain
		iptables -t mangle -A qos_egress -j CONNMARK --save-mark --mask $upload_mask
	fi



	#Only if both upload and download QoS are enabled can we enable Gargoyle active QoS monitor
	if [ $total_download_bandwidth -eq 0 ] || [ $total_upload_bandwidth -eq 0 ] ; then
		qos_monenabled = "false" ;
	fi

	if [ $total_download_bandwidth -ge 0 ] ; then
		# Set up the InterMediate Queuing device (IMQ0) for ingress
		ip link set imq0 up

		# Attach ingress queuing discipline to IMQ0 with temporary default
		tc qdisc add dev imq0 root handle 1:0 hfsc default 1

		# For the root qdisc, only ul is relevant, since there is no link sharing, and rt only applies to leaf qdiscs
		tc class add dev imq0 parent 1:0 classid 1:1 hfsc ls rate 1000Mbit ul m2 ${total_download_bandwidth}kbit

		#load download classes
		$echo_off
		download_class_list=$(load_all_config_sections "$config_file_name" "download_class")
		for dclass_name in $download_class_list ; do
			percent_bandwidth=""
			min_bandwidth=""
			max_bandwidth=""
			minRTT=""

			load_all_config_options "$config_file_name" "$dclass_name"
			if [ -z "$percent_bandwidth" ] ; then
				percent_bandwidth="0"
			fi
			if [ -z "$min_bandwidth" ] ; then
				min_bandwidth="-1"
			fi
			if [ -z "$max_bandwidth" ] ; then
				max_bandwidth="-1"
			fi
            
			classdef="$percent_bandwidth $max_bandwidth $min_bandwidth $minRTT"
			eval $dclass_name=\"\$classdef\"  #"#comment quote here so formatting in editor isn't FUBAR
		done


		class_mark_list=""
		download_shift=8
		next_class_index=2
		next_classid=$(printf "0x%X" $(($next_class_index << $download_shift)) )
		def_download_idx=$next_class_index
		def_download_class=$next_classid

		for dclass_name in $download_class_list ; do
			$echo_on
			class_mark_list="$class_mark_list$dclass_name:$next_classid  "
			dclass_def=$(eval echo "\$$dclass_name")

			#bandwidth for this class
			m2=$(( 10 * $(echo $dclass_def | awk ' {print $1}' ) ))

			#The Gargoyle ACC switches from optimum WAN utilization mode to minimum RTT mode
			#when it detects a class has become active that includes a two part service curve.
			#So to trigger this behaviour we create two parts curves when minRTT is set. 
            
			#Calculations for the delay parameter. Assuming PKT is the packet size the best we
			#could possibly do is PKT/total_download_bandwidth. If we do nothing we get the
			#worst delay of PKT/$m2 (the class bandwidth). Since this class has minRTT set we
			#are going to select the best case and allow up to one max size packet to go at the highest
			#speed.

			#is there an upper limit specified?
			max_bandwidth=$( echo $dclass_def | awk ' {print $2}' )
			ul_str=""
			if [ "$max_bandwidth" -ge 0 ] ; then
				ul_str=" ul m2 ${max_bandwidth}kbit"
			else
				max_bandwidth="$total_download_bandwidth"
			fi

			#How about a link share in percent?
			minRTT=$( echo $dclass_def | awk ' {print $4}' )
			if [ "$minRTT" = "Yes" ] ; then
				d1=$((15000/$max_bandwidth+1))
				ll_str=" ls m1 $((2*$m2))Mbit d ${d1}ms m2 ${m2}Mbit"
			else
				ll_str=" ls m2 ${m2}Mbit"
			fi

			#is there a minimum bandwidth specified?
			min_bandwidth=$( echo $dclass_def | awk ' {print $3}' )
			rt_str=""
			if [ "$min_bandwidth" -gt 0 ] ; then
				if [ "$minRTT" = "Yes" ] ; then
					d2=$((15000/$max_bandwidth+1))
					rt_str=" rt m1 $(($max_bandwidth))kbit d ${d2}ms m2 ${min_bandwidth}kbit"
				else
					rt_str=" rt m2 ${min_bandwidth}kbit"
				fi
			fi


			tbw=$(($max_bandwidth*100/8));
			if [ "$tbw" -lt 10000 ] ; then
				tbw=10000
			fi

			tc class add dev imq0 parent 1:1 classid 1:$next_class_index hfsc $rt_str $ll_str $ul_str
			#Assume average download packet size is 250 bytes.
			tc qdisc add dev imq0 parent 1:$next_class_index handle $next_class_index:1 sfq headdrop limit $(($tbw/250)) $sfq_depth divisor 256  
			tc filter add dev imq0 parent 1:0 prio $next_class_index protocol ip handle $next_classid fw flowid 1:$next_class_index
			tc filter add dev imq0 parent $next_class_index: handle 1 flow divisor 256 map key dst and 0xff
			$echo_off

			if [ "$download_default_class" = "$dclass_name" ] ; then
				def_download_idx=$next_class_index
				def_download_class=$next_classid
			fi

			next_class_index=$(($next_class_index+1))
			next_classid=$(printf "0x%X" $(($next_class_index << $download_shift)) )
		done

		$echo_on

		#Go back and touch up the root qdisc to have the proper default class
		tc qdisc change dev imq0 $overhead root handle 1:0 hfsc default $def_download_idx

		# Create ingress chain
		iptables -t mangle -N qos_ingress

		# Mark ingress in FORWARD and INPUT chains to make sure any DNAT (virt. server) is taken into account
		iptables -t mangle -A FORWARD -i $qos_interface -j qos_ingress
		iptables -t mangle -A INPUT -i $qos_interface -j qos_ingress

		#Now the rest of the user entered rules.
		$echo_off
		apply_all_rules "download_rule" "$class_mark_list" "qos_ingress" "mangle" "$download_mask"
		$echo_on

		#set default class mark first in case we don't match anything
		iptables -t mangle -I qos_ingress -j MARK --set-mark $def_download_class

		#If we already set a mark in quota chain, we need to save that mark to the connmark, then return so it doesn't get over-written
		iptables -t mangle -I qos_ingress -m mark ! --mark 0x0 -j RETURN
		iptables -t mangle -I qos_ingress -m mark ! --mark 0x0 -j CONNMARK --save-mark --mask $download_mask

		#Make sure all packets get sent through IMQ
		iptables -t mangle -I qos_ingress -j IMQ --todev 0

		#save current mark to connmark at end of chain
		iptables -t mangle -A qos_ingress -j CONNMARK --save-mark --mask $download_mask

		$echo_off

	fi

	#Enable Gargoyle active QoS monitor
	if [ $total_upload_bandwidth -ge 0 ] && [ $total_download_bandwidth -ge 0 ] && [ "$qos_monenabled" = "true" ] ; then

		$echo_on

		#if the user specified a ping target then use that otherwise use the gateway.
		if [ -z "$ptarget_ip" ] ; then
			old_ifs="$IFS"
			IFS=$(printf "\n\r")
			targets=$(traceroute -n -I -w 1 -q 2 -m6 8.8.8.8 | grep -o '[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}.*ms' | grep -v '8.8.8.8' | sed 's/ms//g')
			ptarget_ip=""
			for t in $targets ; do
				if [ -z "$ptarget_ip" ] ; then
					#ip of potential gateway
					target=$(echo "$t" | awk '{ print $1 ; }')
					target_is_local=$(echo "$target" | grep -E '^(192\.168|10\.|172\.1[6789]\.|172\.2[0-9]\.|172\.3[01]\.|0\.0\.0\.0|127\.|255\.)') 


					# round or rather ceil() time up to nearest millisecond since bash doesn't like working with decimals
					time=$(echo "$t" | awk ' { print $3 ; }' | sed 's/\..*$//g')
					time=$(( $time + 1 ))
	
					if [ -z "$target_is_local" ] || [ "$time" -gt 5 ] ; then
						ptarget_ip="$target"
					fi
				fi
			done
			IFS="$old_ifs"
			
			#in case ping target is still not defined use default gateway
			if [ -z "$ptarget_ip" ] ; then
				ptarget_ip=$(gargoyle_header_footer -i gargoyle | sed -n 's/.*currentWanGateway.*"\(.*\)".*/\1/p')
			fi
		fi

		
		#Ping responses from the ping target never go to ingress QoS (IMQ0 device).
		iptables -t mangle -I qos_ingress -p icmp --icmp-type 0 -s $ptarget_ip -j RETURN

		#Make a class to handle the outgoing ping requests from the router.
		#These pings 84 bytes each for ethernet plus 22 more for PPPoE connections, allowing a maximum rate of 200ms we get 2.6kbps
		tc class add dev $qos_interface parent 1:1 classid 1:127 hfsc rt umax 106 dmax 10ms rate 4kbit
		tc qdisc add dev $qos_interface parent 1:127 pfifo
		tc filter add dev $qos_interface parent 1:0 prio 1 protocol ip handle 127 fw flowid 1:127

		#Mark all ping requests from the router to the ptarget to the above special class overriding any other mark.
		iptables -t mangle -I qos_egress -p icmp --icmp-type 8 -s $wan_ip -d $ptarget_ip -j MARK --set-mark 127

		#Start the monitor
		if [ -n "$pinglimit" ] ; then
			#In manual mode the user selects the active mode pinglimit indirectly.  qosmon always measures the RTT of a ping on an unloaded link.
			#This is called the ping entitlement.  With a manual entry the minRTT ping limit is 110% of this measured ping entitlement
			#and the active mode ping limit is the minRTT limit plus the user entered value.  See the qosmon source code for more details.
			#In summary manaully entered ping times only affect the active mode, not the minRTT mode ping time limits.
			qosmon -a -b 800 $ptarget_ip $total_download_bandwidth $pinglimit
		else
			#In auto mode we calculate transmission delay based on our bandwidth and then ask qosmon
			#to add this value to its measured ping entitlement to form the final ping limit.
			pinglimit=$((1500*10*2/3/$total_download_bandwidth+1500*10/$total_upload_bandwidth+2))
			qosmon -a -b 800 $ptarget_ip $total_download_bandwidth $pinglimit
		fi

		$echo_off
	fi

	update_markfile

}


define_interface()
{
	$echo_on
	#Wait for up to 15 seconds for the wan interface to indicate it is up.
	wait_sec=15
	while [ -z $(uci -P /var/state get network.wan.up 2>/dev/null) ] && [ $wait_sec -gt 0 ] ; do
		sleep 1
		wait_sec=$(($wait_sec - 1))
	done

	#The wan interface name will depend on if pppoe is used or not.  If pppoe is used then
	#the name we are looking for is in network.wan.ifname.  If there is nothing there
	#use the device named by network.wan.device

	qos_interface=$(uci -P /var/state get network.wan.ifname 2>/dev/null)
	if [ -z $qos_interface ] ; then
		qos_interface=$(uci -P /var/state get network.wan.device 2>/dev/null)
	fi

	#Determine our wan ip from the wan interface we detected.
	wan_ip=$(ifconfig $qos_interface | sed -n 's/.*inet addr:\([0-9/.]*\).*/\1/p')
	local_ip=$(ifconfig br-lan | sed -n 's/.*inet addr:\([0-9/.]*\).*/\1/p')

	#Determine the VPN interface if there is one.
	vpn_interface=$(uci -P /var/state get firewall.vpn_zone.device 2>/dev/null)
	$echo_off
}

stop()
{
	#if already in process of being initialized, do not continue
	#until that is finished, and then exit cleanly, without
	#doing anything further
	if [ -e "$lock_file" ] ; then
		while [ -e "$lock_file" ] ; do
			sleep 1
		done
		exit
	fi

	#Kill the qos monitor in case it is running
	killall qosmon 2>/dev/null


	$echo_on
	#Delete the qdiscs we hung on the devices
	for iface in $(tc qdisc show | grep hfsc | awk '{print $5}'); do
		tc qdisc del dev "$iface" root
	done

	# eliminate existing rules in mangle table
	delete_chain_from_table "mangle" "qos_egress"
	delete_chain_from_table "mangle" "qos_ingress"
	$echo_off

}


start()
{
	test_total_up=$(uci get qos_gargoyle.upload.total_bandwidth 2>/dev/null)
	test_total_down=$(uci get qos_gargoyle.download.total_bandwidth 2>/dev/null)
	if [ -z "$test_total_up" ] && [ -z "$test_total_down" ] ;then
		disable
		exit 0
	fi


	#This script is called by a hotplug event.  If the WAN comes
	#up fast we could end up trying to run qos_gargoyle while the
	#boot is still in progress which causes issues in low memory
	#routers.  To avoid this we check to see if rcS is still running 
	#or not.  If it is we wait until it completes or 60 seconds.
	cnt=0
	while ps | grep '[//]rcS S boot' >/dev/null
		do
			sleep 4
			cnt=`expr $cnt + 1`
			if [ $cnt -ge 15 ] ; then
				break;
			fi
		done

	stop
	touch "$lock_file"

	#load qos_interface from global variables
	define_interface
	if [ -n "$qos_interface" ] ; then

		load_all_config_options "$config_file_name" "global"
		initialize_qos
	fi

	rm -rf "$lock_file"

}

restart()
{
	echo_on="set -x"
	echo_off="set +x"
	start "$1"
}

show()
{
	#load global variables
	load_all_config_options "$config_file_name" "global"

	#load qos_interface from global variables
	define_interface

	echo "Egress configuration on $qos_interface"
	iptables -t mangle -vnL qos_egress 2>/dev/null
	tc -s qdisc show dev $qos_interface
	tc -s class show dev $qos_interface
	tc -s filter show dev $qos_interface

	echo "Ingress configuration in imq0"
	iptables -t mangle -vnL qos_ingress 2>/dev/null
	tc -s qdisc show dev imq0
	tc -s class show dev imq0
	tc -s filter show dev imq0
	tc -s filter show dev imq0 parent 2:
}

boot()
{
	#Do nothing during init.  Start is called by hotplug.
	return
}

