#!/bin/bash
#
# Author: Jesper Dangaaard Brouer <netoptimizer@brouer.com>
# License: GPLv2
#
basedir=`dirname $0`
source ${basedir}/functions.sh

root_check_run_with_sudo "$@"

# Use common parameters
source ${basedir}/parameters.sh

export TC=tc

# This can be changed via --file or --obj
if [[ -z ${BPF_OBJ} ]]; then
    # Fallback default
    BPF_OBJ=edt_pacer_vlan.o
fi

info "Applying TC-BPF egress setup on device: $DEV with object file: $BPF_OBJ"

function tc_remove_clsact()
{
    local device=${1:-$DEV}
    shift

    # Removing qdisc clsact, also deletes all filters
    call_tc_allow_fail qdisc del dev "$device" clsact 2> /dev/null
}

function tc_init_clsact()
{
    local device=${1:-$DEV}
    shift

    # TODO: find method that avoids flushing (all users)

    # Also deletes all filters
    call_tc_allow_fail qdisc del dev "$device" clsact 2> /dev/null

    # Load qdisc clsact which allow us to attach BPF-progs as TC filters
    call_tc qdisc add dev "$device" clsact
}

function tc_egress_bpf_attach()
{
    local device=${1:-$DEV}
    local objfile=${2:-$BPF_OBJ}
    shift 2

    # TODO: Handle selecting program 'sec'
    call_tc filter add dev "$device" pref 2  handle 2 \
            egress bpf da obj "$objfile"
}

function tc_egress_list()
{
    local device=${1:-$DEV}

    call_tc filter show dev "$device" egress
}

if [[ -n $REMOVE ]]; then
    tc_remove_clsact $DEV
    exit 0
fi

tc_init_clsact $DEV
tc_egress_bpf_attach $DEV $BPF_OBJ

# Practical to list egress filters after setup.
# (It's a common mistake to have several progs loaded)
if [[ -n $LIST ]]; then
    info "Listing egress filter on device"
    tc_egress_list $DEV
fi