#!/bin/bash 

# Wonder Shaper

LOCKFILE=/var/lock/subsys/wshaperx

source /etc/wshaperx.conf
if [ "$DOWNLINK" = "" -o "$UPLINK" = "" ]
then
    echo "Please read the documentation in 'README' and set "
    echo "the downlink and uplink speeds in /etc/wshaperx.conf."
    exit 3
fi

if [ "$DEV" == "" ]
then
    echo "Please read the documentation in 'README' and set "
    echo "the device in /etc/wshaperx.conf."
    exit 3
fi

if [ "$DISCIPLINE" != "cbq" -a "$DISCIPLINE" != "htb" ]
then
    echo "Unknown queuing discipline '$DISCIPLINE' in "
    echo "/etc/wshaperx.conf. Please use 'cbq' or 'htb' only."
    exit 3
fi

#########################################################

status() {
    tc -s qdisc ls dev $DEV
    tc -s class ls dev $DEV
}

unshape() {
    # clean existing down- and uplink qdiscs, hide errors
    tc qdisc del dev $DEV root    2> /dev/null > /dev/null
    tc qdisc del dev $DEV ingress 2> /dev/null > /dev/null
}

reshape() {
    # Change existing classes and replace existing filters,
    # rather than redoing everything from scratch, to avoid
    # disruption of shaping, and to continue statistics.
    tc class change dev $DEV parent 1: classid 1:1 ${DISCIPLINE} \
	rate ${UPLINK}kbit
    tc class change dev $DEV parent 1:1 classid 1:10 ${DISCIPLINE} \
	rate ${UPLINK}kbit
    tc class change dev $DEV parent 1:1 classid 1:20 ${DISCIPLINE} \
	rate $[9*$UPLINK/10]kbit
    tc class change dev $DEV parent 1:1 classid 1:30 ${DISCIPLINE} \
	rate $[8*$UPLINK/10]kbit
    tc filter replace dev $DEV parent ffff: protocol ip \
	prio 50 u32 match ip src \
	0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1
}

########### uplink ##############

addrootcbq() {
    # install root CBQ
    tc qdisc add dev $DEV root handle 1: cbq avpkt 1000 bandwidth 10mbit 
}

addroothtb() {
    # install root HTB, point default traffic to 1:20:
    tc qdisc add dev $DEV root handle 1: htb default 20
}

addshapecbq() {
    # shape everything at $UPLINK speed - this prevents huge
    # queues in your DSL modem which destroy latency:
    tc class add dev $DEV parent 1: classid 1:1 cbq \
	rate ${UPLINK}kbit allot 1500 prio 5 bounded isolated 

    # high prio class 1:10:
    tc class add dev $DEV parent 1:1 classid 1:10 cbq \
	rate ${UPLINK}kbit allot 1600 prio 1 avpkt 1000

    # bulk and default class 1:20 - gets slightly less traffic, 
    #  and a lower priority:
    tc class add dev $DEV parent 1:1 classid 1:20 cbq \
	rate $[9*$UPLINK/10]kbit allot 1600 prio 2 avpkt 1000

    # 'traffic we hate' 1:30
    tc class add dev $DEV parent 1:1 classid 1:30 cbq \
	rate $[8*$UPLINK/10]kbit allot 1600 prio 2 avpkt 1000
}

addshapehtb() {
    # shape everything at $UPLINK speed - this prevents huge 
    # queues in your DSL modem which destroy latency:
    tc class add dev $DEV parent 1: classid 1:1 htb \
	rate ${UPLINK}kbit burst 6k

    # high prio class 1:10:
    tc class add dev $DEV parent 1:1 classid 1:10 htb \
	rate ${UPLINK}kbit burst 6k prio 1

    # bulk & default class 1:20 - gets slightly less traffic, 
    # and a lower priority:
    tc class add dev $DEV parent 1:1 classid 1:20 htb \
	rate $[9*$UPLINK/10]kbit burst 6k prio 2

    # 'traffic we hate' 1:30
    tc class add dev $DEV parent 1:1 classid 1:30 htb \
	rate $[8*$UPLINK/10]kbit burst 6k prio 2
}

addsfq() {
    # all get Stochastic Fairness:
    tc qdisc add dev $DEV parent 1:10 handle 10: sfq perturb 10
    tc qdisc add dev $DEV parent 1:20 handle 20: sfq perturb 10
    tc qdisc add dev $DEV parent 1:30 handle 30: sfq perturb 10
}

addmindelay() {
    # TOS Minimum Delay (ssh, NOT scp) in 1:10:
    tc filter add dev $DEV parent 1:0 protocol ip prio 10 u32 \
	match ip tos 0x10 0xff  flowid 1:10
}

addicmp() {
    # ICMP (ip protocol 1) in the interactive class 1:10 so we 
    # can do measurements & impress our friends:
    tc filter add dev $DEV parent 1:0 protocol ip prio 11 u32 \
	match ip protocol 1 0xff flowid 1:10
}

addsmallpackets() {
    # prioritize small packets (<64 bytes)
    tc filter add dev $DEV parent 1: protocol ip prio 12 u32 \
	match ip protocol 6 0xff \
	match u8 0x05 0x0f at 0 \
	match u16 0x0000 0xffc0 at 2 \
	flowid 1:10
}

addack() {
    # To speed up downloads while an upload is going on, put ACK 
    # packets in the interactive class:
    tc filter add dev $DEV parent 1: protocol ip prio 10 u32 \
	match ip protocol 6 0xff \
	match u8 0x05 0x0f at 0 \
	match u16 0x0000 0xffc0 at 2 \
	match u8 0x10 0xff at 33 \
	flowid 1:10
}

addnoprio() {
    # some traffic however suffers a worse fate

    for a in $NOPRIOPORTDST
    do
        tc filter add dev $DEV parent 1: protocol ip prio 14 u32 \
	    match ip dport $a 0xffff flowid 1:30
    done

    for a in $NOPRIOPORTSRC
    do
        tc filter add dev $DEV parent 1: protocol ip prio 15 u32 \
	    match ip sport $a 0xffff flowid 1:30
    done

    for a in $NOPRIOHOSTSRC
    do
        tc filter add dev $DEV parent 1: protocol ip prio 16 u32 \
	    match ip src $a flowid 1:30
    done

    for a in $NOPRIOHOSTDST
    do
        tc filter add dev $DEV parent 1: protocol ip prio 17 u32 \
	    match ip dst $a flowid 1:30
    done
}

addrest() {
    # rest is 'non-interactive' ie 'bulk' and ends up in 1:20

    tc filter add dev $DEV parent 1: protocol ip prio 18 u32 \
	match ip dst 0.0.0.0/0 flowid 1:20
}

########## downlink #############

addpolicer() {
    # slow downloads down to somewhat less than the real speed  
    # to prevent queuing at our ISP. Tune to see how high you can 
    # set it. ISPs tend to have *huge* queues to make sure big 
    # downloads are fast.

    # attach ingress policer:
    tc qdisc add dev $DEV handle ffff: ingress

    # filter *everything* to it (0.0.0.0/0), drop everything that's
    # coming in too fast:
    tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \
	0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1
}

case "$1" in
    status)
	if ! [ -f $LOCKFILE ]
	then
	    echo "wshaperx is not running."
	fi
	status	
	;;
    stop)
	unshape
	rm -f $LOCKFILE
	;;
    reload)
	if ! [ -f $LOCKFILE ]
	then
	    echo "wshaperx is not running."
	    exit 1
	fi
	reshape
	;;
    start | restart)
	if [ "$DISCIPLINE" = "cbq" ]
        then
	    unshape
            # create queues
	    addrootcbq
	    addshapecbq
	    addsfq
            # start upstream filters
	    addmindelay
	    addicmp
	    addsmallpackets
	    addnoprio
	    addrest
	    # start downstream filter
	    addpolicer
	else
	    unshape
	    # create queues
	    addroothtb;
	    addshapehtb;
	    addsfq;
            # start filters
	    addmindelay
	    addicmp
	    addack
	    addnoprio
	    addrest
	    # start downstream filter
	    addpolicer
	fi
	touch $LOCKFILE
	;;
    *)
	echo "usage: %0 {start|stop|restart|reload|status}"
	exit 1
	;;
esac

exit 0
