#!/bin/sh

: <<=cut

=head1 NAME

ipt_basic_ - monitor traffic through iptables


=head1 APPLICABLE SYSTEMS

This plugin was designed to monitor FORWARDING interfaces
on a router with only one-to-one forwarding (traffic goes into
one interface goes out to the other).


=head1 CONFIGURATION

You can initialise the required iptables by running it manually:

  ipt-basic_ initialise

You should create two symlinks to this module:
  ln -s ipt-basic_ ipt-basic_bytes
  ln -s ipt-basic_ ipt-basic_pkts

This plugin is based on the ip_ plugin.


=head1 REVISIONS

=over 4

=item 2006.01.00 - First release.

=item 2006.11.26 - Use -j RETURN in rules, and sort interfaces

=back


=head1 AUTHORS

Copyright (C) 2005 Peter Gervai


=head1 LICENSE

GNU Library General Public License v2 only

SPDX-License-Identifier: GPL-2.0-only


=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

# ipt_bytes, ipt_pkts
TYPE=`basename $0 | sed 's/^ipt-basic_//g'`

if [ "$TYPE" != "bytes" -a "$TYPE" != "pkts" ]; then
	# if dear user forgot to use symlinks, default to ipt_bytes
	TYPE='bytes'
fi

# name of our iptable
TNAME='munin_node'
iptables='/sbin/iptables'


if [ "$1" = "autoconf" ]; then
	if [ -r /proc/net/dev ]; then
		RES=`$iptables -L $TNAME -nvx -w 2>&1 >/dev/null`
		if [ $? -gt 0 ]; then
			echo "no (could not run iptables as user `whoami`; $RES)"
		else
			echo yes
		fi
	else
		echo "no (/proc/net/dev not found)"
	fi
	exit 0
fi

if [ "$1" = "suggest" ]; then
        echo "no parameters required!"
	exit 1
fi


if [ "$1" = "initialise" ]; then
	# creates the required tables
        $iptables -N $TNAME
        $iptables -F $TNAME
        # add to forward table (and delete dupe if exists
        $iptables -D FORWARD -j $TNAME 2> /dev/null
        $iptables -A FORWARD -j $TNAME
        DEVS=`cat /proc/net/dev|egrep "(eth|ppp)" | cut -d: -f1 | sort`
        for dev in $DEVS; do
        	$iptables -A $TNAME -j RETURN -i $dev
        done
	exit 1
fi

IFACES=`$iptables -L munin_node -nvx -w | awk '$6 ~ /(eth|ppp)[0-9]/ { if (done[$6]!=1) {print $6; done[$6]=1;}}'`

if [ "$1" = "config" ]; then

        # echo "graph_order out in"
        if [ "$TYPE" = "pkts" ]; then
        	echo "graph_title pkts"
	        echo 'graph_vlabel pkts per ${graph_period}'
        else
	        echo "graph_title traffic"
	        echo 'graph_vlabel bits per ${graph_period}'
        fi
        echo 'graph_args --base 1000'
	echo 'graph_category network'
        echo 'graph_info This graph shows the traffic of the interfaces in bits per second, and should be precise above 50Mbps as well. All forwarded traffic is measured in the incoming counter of the given interface.'

        for iface in $IFACES; do
        	echo "$iface.label ${iface}_received"
                echo "$iface.type DERIVE"
                echo "$iface.min 0"
	        if [ "$TYPE" != "pkts" ]; then
        	        # traf in BITS/sec
                	echo "$iface.cdef $iface,8,*"
                fi
        done
        exit 0
fi;

if [ "$TYPE" = "pkts" ]; then
	$iptables -L munin_node -nvx -w | egrep "eth|ppp" | awk "{ print \$6 \".value \" \$1 }"
else
	$iptables -L munin_node -nvx -w | egrep "eth|ppp" | awk "{ print \$6 \".value \" \$2 }"
fi