macos pfctl dnctl example script

network_link_conditioner.sh

#!/bin/bash
# https://techracho.bpsinc.jp/hachi8833/2017_04_04/38229
# https://gist.github.com/mefellows/4f6ecd2e83de8b591726
#
# for localhost:3000

reset() {
  dnctl -q flush
  pfctl -f /etc/pf.conf
  pfctl -d
}

status() {
  echo
  dnctl list
}

shape_traffic() {
  pfctl -e
  IN_OUT=in   # in: connect to localhost, out: outgoing.
  PORT=3000   # port number
  (cat /etc/pf.conf && echo "dummynet-anchor \"mop\"" && echo "anchor \"mop\"") | pfctl -f -
  echo "dummynet $IN_OUT quick proto tcp from any to any port $PORT pipe 1" | pfctl -a mop -f -
}

BW=56kbit/s
DELAY=1000

case "$1" in
-r)
  reset
  status
  ;;
bw)
  shape_traffic
  dnctl pipe 1 config bw $BW
  status
  ;;
delay)
  shape_traffic
  dnctl pipe 1 config delay $DELAY
  status
  ;;
both)
  shape_traffic
  dnctl pipe 1 config bw $BW delay $DELAY
  status
  ;;
*)
  echo $0 "<-r|bw|delay|both>"
  ;;
esac

network_link_conditioner_2.sh

#!/bin/bash
# https://techracho.bpsinc.jp/hachi8833/2017_04_04/38229
# https://gist.github.com/mefellows/4f6ecd2e83de8b591726
#
# for localhost:3000 and https

reset() {
  dnctl -q flush
  pfctl -f /etc/pf.conf
  pfctl -d
}

status() {
  echo
  dnctl list
}

shape_traffic() {
  pfctl -e
  (cat /etc/pf.conf && cat) <<__PF__ | pfctl -f -
dummynet-anchor "mop"
anchor "mop"
__PF__
  cat <<__MOP__ | pfctl -a mop -f -
dummynet in  quick proto tcp from any to any port 3000 pipe 1
dummynet out quick proto tcp from any to any port 443  pipe 2
__MOP__
}

BW=56kbit/s
DELAY=1000

case "$1" in
-r)
  reset
  status
  ;;
bw)
  shape_traffic
  dnctl pipe 1 config bw $BW
  dnctl pipe 2 config bw $BW
  status
  ;;
delay)
  shape_traffic
  dnctl pipe 1 config delay $DELAY
  dnctl pipe 2 config delay $DELAY
  status
  ;;
both)
  shape_traffic
  dnctl pipe 1 config bw $BW delay $DELAY
  dnctl pipe 2 config bw $BW delay $DELAY
  status
  ;;
*)
  echo $0 "<-r|bw|delay|both>"
  ;;
esac