#!/bin/sh
# /etc/rc.d/rc.tcpip_proc_customize
#!/bin/bash
#
# to execute:
# <scriptname> <dev> <start|stop|restart>
# example: bash# ./script ppp0 start
#
configuration_start() {
echo "Setting /proc/ipv4 custom configuration, activating qdiscs."

  if [ -f /proc/sys/net/ipv4/ip_forward ]; then
    echo "Activating IPv4 packet forwarding."
    echo 1 > /proc/sys/net/ipv4/ip_forward
  fi

  if [ -f /proc/sys/net/ipv4/ip_dynaddr ]; then
    echo "Activating IPv4 dynamic ip address."
    echo 1 > /proc/sys/net/ipv4/ip_dynaddr
  fi

  if [ -f /proc/sys/net/ipv4/tcp_sack ]; then
    echo "Activating IPv4 selective ACK."
    echo 1 > /proc/sys/net/ipv4/tcp_sack
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_time ]; then
    echo "Setting IPv4 TCP-keepalive sends to every 30 minutes."
    echo 1800 > /proc/sys/net/ipv4/tcp_keepalive_time
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_intvl ]; then
    echo "Setting IPv4 TCP-keepalive re-send unACKeds to 30 second intervals."
    echo 30 > /proc/sys/net/ipv4/tcp_keepalive_intvl
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_probes ]; then
    echo "Setting IPv4 TCP-keepalive repeat re-send unACKeds to 20 retries."
    echo 20 > /proc/sys/net/ipv4/tcp_keepalive_probes
  fi

  if [ -f /proc/sys/net/ipv4/tcp_slow_start_after_idle ]; then
    echo "Setting IPv4 TCP-slow start after idle, to false."
    echo 0 > /proc/sys/net/ipv4/tcp_slow_start_after_idle
  fi

# Begin HTB qdisc configuration:

# first define our qdiscs
# here is the main one, the root qdisk which is on ppp0
# the handle is 1:
tc qdisc add dev $1 root handle 1: htb 
# now, the parent class (handle 1:1) is the main class on qdisc 1: above
# and has available the full bandwidth
tc class add dev $1 parent 1:  classid 1:1  htb rate 2.5kbps burst 4k
# the 4 classids below are supposed to share the bw of the parent class
# eth0 classes:
# classid 1:10 has a lower priority 2  and lower avail bw; will be for incoming ftp
# classid 1:11 has higher priority 1, and higher avail bw; will be for other (http etc..) incoming
tc class add dev $1 parent 1:1 classid 1:10 htb rate 1.26kbps ceil 2.5kbps prio 3
tc class add dev $1 parent 1:1 classid 1:11 htb rate 1.26kbps ceil 2.5kbps prio 2
# eth1 classes, same idea as above on eth0
tc class add dev $1 parent 1:1 classid 1:12 htb rate 1.26kbps ceil 2.5kbps prio 3
tc class add dev $1 parent 1:1 classid 1:13 htb rate 1.26kbps ceil 2.5kbps prio 2



tc qdisc add dev $1 handle ffff: ingress
tc filter add dev $1 parent ffff: protocol ip prio 1 u32 \
	match ip src 0.0.0.0/0 police rate 2.5kbps burst 4k drop flowid :1


# all routes get stochastic fairness: (what does that mean??)
tc qdisc add dev $1 parent  1:10 handle 10: sfq perturb 10
tc qdisc add dev $1 parent  1:11 handle 11: sfq perturb 10
tc qdisc add dev $1 parent  1:12 handle 12: sfq perturb 10
tc qdisc add dev $1 parent  1:13 handle 13: sfq perturb 10

# prioritize ACK packets: put ACKs into the 'interactive' class
# which means they are given high priority; this increases responsiveness
# when using www or similar services. ACK traffic gets bw directly from the  main parent
# class (classid 1:1) hence the "flowid 1:1"
tc filter add dev $1 parent 1: protocol ip prio 1 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 1:1


# put eth0 ftp traffic traffic into lower priority eth0 category
tc filter add dev $1 protocol ip parent 1:0 prio 3 u32 \
	match ip dst 192.168.0.88 \
	match ip protocol 6 0xff \
	flowid 10:
# all other eth0 traffic into higher priority
tc filter add dev $1 protocol ip parent 1:0 prio 2 u32 \
	match ip dst 192.168.0.88 \
	flowid 11:
# and repeat same for eth1:
tc filter add dev $1 protocol ip parent 1:0 prio 3 u32 \
	match ip dst 192.168.2.88 \
	match ip protocol 6 0xff \
	flowid 12:
tc filter add dev $1 protocol ip parent 1:0 prio 2 u32 \
	match ip dst 192.168.2.88 \
	flowid 13:

# Ingress policing; This here accepts packets at near the maximum possible
# rate that our ppp0 connection can handle, and drops everything it cannot handle;
# meanwhile it tells the other end (the ISP) that we can only receive data at
# *this* rate, and so they should slow down their transmission and not try to queue
# so much data and jam it over the line to us because we will only drop it anyway. 
# This polices ALL inbound traffic on ppp0 and keeps it at or near our max
# receiving rate.

}


configuration_stop() {

echo "rc.optimize_tcpip: restoring default /proc/ipv4 settings, removing qdiscs."

  if [ -f /proc/sys/net/ipv4/ip_forward ]; then
    echo 0 > /proc/sys/net/ipv4/ip_forward
  fi

  if [ -f /proc/sys/net/ipv4/ip_dynaddr ]; then
    echo 0 > /proc/sys/net/ipv4/ip_dynaddr
  fi

  if [ -f /proc/sys/net/ipv4/tcp_sack ]; then
    echo 0 > /proc/sys/net/ipv4/tcp_sack
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_time ]; then
    echo 7200 > /proc/sys/net/ipv4/tcp_keepalive_time
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_intvl ]; then
    echo 75 > /proc/sys/net/ipv4/tcp_keepalive_intvl
  fi

  if [ -f /proc/sys/net/ipv4/tcp_keepalive_probes ]; then
    echo 9 > /proc/sys/net/ipv4/tcp_keepalive_probes
  fi

  if [ -f /proc/sys/net/ipv4/tcp_slow_start_after_idle ]; then
    echo 1 > /proc/sys/net/ipv4/tcp_slow_start_after_idle
  fi

# clean existing down- and uplink qdiscs, hide errors
tc qdisc del dev $1 root 2>&1 1> /dev/null
tc qdisc del dev $1 ingress 2>&1 1> /dev/null
}


# Reconfig the configuration:
configuration_restart() {
  configuration_stop $1
  sleep 1
  configuration_start $1
}


if [ ! "$1" -o ! "$2" ]; then
echo "rc.optimize_tcpip: missing argument-- please specify <dev> [start | stop | restart]"
exit 1
fi

case "$2" in
'start')
  configuration_start $1
  ;;
'stop')
  configuration_stop $1
  ;;
'restart')
  configuration_restart $1
  ;;
  *)
  echo "rc.optimize_tcpip: please specify $1 [ start | stop | restart ]"
;;
esac

#EOF