#!/usr/bin/perl
# Module: vyatta-gateway-static_route-check.pl
#
# **** License ****
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# A copy of the GNU General Public License is available as
# `/usr/share/common-licenses/GPL' in the Debian GNU/Linux distribution
# or on the World Wide Web at `http://www.gnu.org/copyleft/gpl.html'.
# You can also obtain it by writing to the Free Software Foundation,
# Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
# MA 02110-1301, USA.
#
# This code was originally developed by Vyatta, Inc.
# Portions created by Vyatta are Copyright (C) 2008 Vyatta, Inc.
# All Rights Reserved.
#
# Author: Mohit Mehta
# Date: June 2008
# Description: Script to check if any one of the 'static route' is
#              equivalent to the 'system gateway-address' if yes, then
#              don't remove route from routing table unless both are
#              unset
# **** End License ****

use strict;
use warnings;
use lib "/opt/vyatta/share/perl5/";

use Vyatta::Config;

sub findStaticDefaultRoute {
    my ( $cfg ) = @_;
    if ($cfg->exists('protocols static')) {
        my @routes = $cfg->listNodes("protocols static route");
        if (@routes > 0) {
            foreach my $route (@routes) {
                if ($route eq '0.0.0.0/0') {
                    return 1;
                }
            }
        }
    }
    return 0;
}

if ( ( $#ARGV == 1 ) && ( $ARGV[0] eq '0.0.0.0/0' ) ) {
    # check when deleting static-route
    my $vcCHECK_GATEWAY = new Vyatta::Config();
    $vcCHECK_GATEWAY->setLevel('system');
    if ( $vcCHECK_GATEWAY->exists('.') ) {
        my $gateway_ip = $vcCHECK_GATEWAY->returnValue('gateway-address');
        if ( defined($gateway_ip) && $gateway_ip eq $ARGV[1] ) {
            exit 1;
        }
    }
} elsif ( $#ARGV == 0 ) {
    if ($ARGV[0] eq 'warn') {
        my $config = new Vyatta::Config();
        my $haveGatewayAddress = $config->exists("system gateway-address");
        my $haveStaticDefaultRoute = findStaticDefaultRoute($config);
        if ($haveGatewayAddress && $haveStaticDefaultRoute) {
            print "Warning:\n";
            print "Both 'system gateway-address' and 'protocols static route 0.0.0.0/0'\n";
            print "are configured. This configuration is not recommended.\n";
        }
    } else {
        # check when deleting gateway-address
        my $vcCHECK_STATIC_ROUTE = new Vyatta::Config();
        $vcCHECK_STATIC_ROUTE->setLevel('protocols static');
        if ( $vcCHECK_STATIC_ROUTE->exists('.') ) {
            my @routes = $vcCHECK_STATIC_ROUTE->listNodes("route");
            if ( @routes > 0 ) {
                foreach my $route (@routes) {
                    if ( $route eq '0.0.0.0/0' ) {
                        my @next_hops =
                            $vcCHECK_STATIC_ROUTE->listNodes("route $route next-hop");
                        foreach my $next_hop (@next_hops) {
                            if ( $next_hop eq $ARGV[0] ) {
                                exit 1;
                            }
                        }
                    }
                }
            }
        }
    }
}
exit 0;