#!/bin/sh
#
# 1st parameter MAX_CLIENTS
# 2nd parameter BASE_PORT


DEV=eth1
# Bandwidth values (in kbits)
BANDWIDTH=3500

# The following must sum $BANDWIDTH or less
VIDEO_BW=3000
CONTROL_BW=300

VIDEO_LEVEL_0_BW=1000
VIDEO_LEVEL_1_BW=800
VIDEO_LEVEL_2_BW=700
VIDEO_LEVEL_3_BW=500

#Buffer length in k
VIDEO_BUFFER=15000

# Priorities to get the remaining bandwidth
# 0 is max (can be repeated)
PRIO_CONTROL=0
PRIO_VIDEO=1
PRIO_OTHER=3

INSMOD=/sbin/insmod

# Load kernel modules
grep -q ^sch_htb /proc/modules || $INSMOD /lib/modules/`uname -r`/sch_htb.o
grep -q ^sch_sfq /proc/modules || $INSMOD /lib/modules/`uname -r`/sch_sfq.o
grep -q ^cls_u32 /proc/modules || $INSMOD /lib/modules/`uname -r`/cls_u32.o

echo "Vai comecar o script"

# Clean existing qdiscs (redirects error output to /dev/null)
tc qdisc del dev $DEV root 2> /dev/null
tc qdisc del dev $DEV ingress 2> /dev/null

echo "Passou pelo del" 

# Creates root qdisc with HTB policy. Default class for packets is 12 (less prio)
tc qdisc add dev $DEV root handle 1: htb default 12

echo "Passou pelo cria qdisc root" 

# Creates a root class hanging from the root qdisc
# This allows other sub-classes of this one to borrow the remaining bandwidth
# If we prescind of this one and hang subclasses directly from the root qdisc
# then the remaining bandwidth is lost (!)
tc class add dev $DEV parent 1: classid 1:1 htb rate ${BANDWIDTH}kbit ceil ${BANDWIDTH}kbit

echo "Passou pela primeira classe" 

# Now creates 3 classes: (1:10 = max prio)
# 1:10 for Control packets
# 1:11 for Video packets
# 1:12 for other packets
tc class add dev $DEV parent 1:1 classid 1:10 htb rate ${CONTROL_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_CONTROL
tc class add dev $DEV parent 1:1 classid 1:11 htb rate ${VIDEO_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_VIDEO
tc class add dev $DEV parent 1:1 classid 1:12 htb rate $(($BANDWIDTH - $VIDEO_BW - CONTROL_BW))kbit ceil ${BANDWIDTH}kbit prio $PRIO_OTHER

echo "Passou por todas as classes" 

# Creates four sub-classes for Vídeo (level 0 (1:13), level 1 (1:14), level 2 (1:15) and level 3 (1:16))
tc class add dev $DEV parent 1:11 classid 1:13 htb rate ${VIDEO_LEVEL_0_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_VIDEO
tc class add dev $DEV parent 1:11 classid 1:14 htb rate ${VIDEO_LEVEL_1_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_VIDEO
tc class add dev $DEV parent 1:11 classid 1:15 htb rate ${VIDEO_LEVEL_2_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_VIDEO
tc class add dev $DEV parent 1:11 classid 1:16 htb rate ${VIDEO_LEVEL_3_BW}kbit ceil ${BANDWIDTH}kbit prio $PRIO_VIDEO

echo "Passou pelas subclasses" 

# Now creates qdiscs to handle the packets of each class
# Since all of them must treat equally concurrent connections we use sqf everywhere

tc qdisc add dev $DEV parent 1:10 handle 10: sfq perturb 10
tc qdisc add dev $DEV parent 1:12 handle 12: sfq perturb 10
tc qdisc add dev $DEV parent 1:13 handle 13: sfq perturb 10
tc qdisc add dev $DEV parent 1:14 handle 14: sfq perturb 10
tc qdisc add dev $DEV parent 1:15 handle 15: sfq perturb 10
tc qdisc add dev $DEV parent 1:16 handle 16: sfq perturb 10

echo "Vai comecar os match" 

# Filters

#tem que especificar primeiro se é um pacote transferido por tcp ou udp (no caso de pacotes de controle é usado tcp)
#depois, a partir do vigésimo byte, que é o campo de opções do cabeçalho ip, deve-se ler os bytes mostrados
#depois disso, passar o fluxo para a classe de pacotes de controle
tc filter add dev $DEV parent 1: \
        protocol ip prio $PRIO_CONTROL \
        u32 match ip protocol 6 0xff \
	match u32 00190000 00ff0000 at 0 \
	flowid 1:10

echo "Passou pelo 1 match" 

#tem que especificar primeiro se é um pacote transferido por tcp ou udp (no caso de pacotes de vídeo é usado udp)
#depois, a partir do vigésimo primeiro byte, que é o campo de opções do cabeçalho ip, deve-se ler os bytes mostrados
#depois disso, passar o fluxo para a classe de pacotes de controle
tc filter add dev $DEV protocol ip parent 1: prio $PRIO_VIDEO u32 \
	match ip protocol 17 0xff \
	match u32 001b0000 00ff0000 at 0 \
	police rate ${VIDEO_LEVEL_0_BW}kbit buffer ${VIDEO_BUFFER}k drop \
	flowid 1:13

echo "Passou pelo 2 match" 

tc filter add dev $DEV protocol ip parent 1: prio $PRIO_VIDEO u32 \
	match ip protocol 17 0xff \
	match u32 000b0000 00ff0000 at 0 \
	police rate ${VIDEO_LEVEL_1_BW}kbit buffer ${VIDEO_BUFFER}k drop \
	flowid 1:14
	
echo "Passou pelo 3 match" 

tc filter add dev $DEV protocol ip parent 1: prio $PRIO_VIDEO u32 \
	match ip protocol 17 0xff \
	match u32 00130000 00ff0000 at 0 \
	police rate ${VIDEO_LEVEL_2_BW}kbit buffer ${VIDEO_BUFFER}k drop \
	flowid 1:15
	
echo "Passou pelo 4 match" 

tc filter add dev $DEV protocol ip parent 1: prio $PRIO_VIDEO u32 \
	match ip protocol 17 0xff \
	match u32 00030000 00ff0000 at 0 \
	police rate ${VIDEO_LEVEL_3_BW}kbit buffer ${VIDEO_BUFFER}k drop \
	flowid 1:16

echo "Passou pelo 5 match"