pf_active_clients

#!/bin/bash

: << =cut

=head1 NAME

Packetfence Clients

=head1 AUTHOR

Contributed by Paul Verrall 

=head1 LICENSE

GPLv2

=cut

if [ -x  $MUNIN_LIBDIR/plugins/plugin.sh ]
then
. $MUNIN_LIBDIR/plugins/plugin.sh
fi

if [ "$1" = "autoconf" ]; then
        echo no
        exit 0
fi

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

        echo "graph_title packetfence active clients"
        echo 'graph_vlabel clients'
        echo 'graph_args --base 1000 --lower-limit 0' 
        echo "graph_category Packetfence"

        PF_IPSETS=$(ipset list -n | fgrep pfsession_Reg_)

        for ipset in $PF_IPSETS
        do
            snet=${ipset##pfsession_Reg_}
            echo "$snet""_active.label $snet""_active"
            echo "$snet.draw AREA"
        done

        exit 0
fi

PF_IPSETS=$(ipset list -n | fgrep pfsession_Reg_)
TCP_TIMEOUT=$(sysctl -n net.netfilter.nf_conntrack_tcp_timeout_established)
ACTIVE_AGE=600
ACTIVE_MIN_AGE=$(( $TCP_TIMEOUT - $ACTIVE_AGE ))

LOCAL_IPS=$(mktemp)
IPSET_CLIENT_IPS=$(mktemp)

# Pop local IPs in a file for easy filtering with grep
for ip in $(hostname -I)
do
    echo "$ip" >> "$LOCAL_IPS"
done

for ipset in $PF_IPSETS;
do
    # output list of set client ips for this set to file for easy greppage
    ipset list "$ipset"  | awk -F , '/^[0-9]/ {print $1}' > "$IPSET_CLIENT_IPS"
    if [ -s "$IPSET_CLIENT_IPS" ]
    then
        echo -n "${ipset##pfsession_Reg_}_active.value "
        
        # list of assured established tcp connections 
        # | remove local sorces and destinations 
        # | remove aged connections i.e only those active within $ACTIVE_AGE seconds
        # | include only pf clients in this ipset
        # | sort | unique | count remaining lines
        
        conntrack -L -u assured -p tcp --state ESTABLISHED 2>/dev/null \
            | fgrep -v -f "$LOCAL_IPS" \
            | awk -v t="$ACTIVE_MIN_AGE" '$3 > t {print $0}' \
            | fgrep -o -f "$IPSET_CLIENT_IPS" \
            | sort | uniq | wc -l
     fi
done

rm $LOCAL_IPS $IPSET_CLIENT_IPS
exit 0