librenms-librenms-agent/snmp/fail2ban

#!/usr/local/bin/perl

# Addthis to snmpd.conf as below.
# extend fail2ban /etc/snmp/fail2ban
#
# Please verify that the tables below are correct for your installation

my @linuxChains=('failban','f2b');
my $freebsdPFtable='fail2ban';

# You should not have to touch anything below this.

my $os=`uname`;

if ( $os =~ '^FreeBSD' ){
	   print `/sbin/pfctl -t $freebsdPFtable -T show | /usr/bin/grep -c .`;
	   exit;
};
   
if ( $os =~ '^Linux' ){
	my $iptables=`iptables -L -n`;

	my @iptablesA=split( /\n/, $iptables );

	#check each line
	my $int=0;
	my $banned=0;
	my $count=0;
	while( defined( $iptablesA[$int] ) ){
		my $line=$iptablesA[$int];

		#stop counting if we have a blank line
		if ( $line =~ /^$/ ){
			$count=0;
		}

		#count /^REJECT/ lines, if we are counting
		if ( ( $line =~ /^REJECT/ ) && ( $count ) ){
			$banned++;
		}

		#check if this is a chain we should count
		if ( $line =~ /^Chain/ ){
			my $linuxChainsInt=0;
			# check if any of the specified names hit and if so start counting
			while( defined( $linuxChains[$linuxChainsInt] ) ){
				my $chain=$linuxChains[$linuxChainsInt];
				if ( $line =~ /^Chain $chain/ ){
					$count=1;
				}
				
				$linuxChainsInt++;
			}
		}		
		
		$int++;
	}
	
	print $banned."\n";
}