#!/usr/bin/perl

use strict;

$ENV{'PATH'} = '/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin';

my $APNIC_URI  = 'http://ftp.apnic.net/stats/apnic/delegated-apnic-latest';
my $CIDR_TABLE = '/etc/postfix/check_client_country';
my %MASK_BITS = (
	'256'=>'24','512'=>'23','1024'=>'22','2048'=>'21','4096'=>'20','8192'=>'19','16384'=>'18','32768'=>'17',
	'65536'=>'16','131072'=>'15','262144'=>'14','524288'=>'13','1048576'=>'12','2097152'=>'11','4194304'=>'10',
	'8388608'=>'9','16777216'=>'8','33554432'=>'7','67108864'=>'6','134217728'=>'5','268435456'=>'4',
	'536870912'=>'3','1073741824'=>'2','2147483648'=>'1'
);

my $FLAG = 0;

if (!open(CMD,"wget $APNIC_URI -O - 2>/dev/null |")) {
	print "Wget process didn't function.\n";
	exit(1);
}
if (!open(TMP,">$CIDR_TABLE.tmp")) {
	print "Can't open $CIDR_TABLE.tmp.\n";
	close(CMD);
	exit(1);
}
eval'flock(TMP,2);';

print TMP '# LastUpdate: ' . localtime(time) . "\n";
print TMP '# [Japan Network]' . "\n";

while (my $LINE = <CMD>) {
	my $CIDR;
	my $TABS;

	if ($LINE =~ /^apnic\|JP\|ipv4\|([0-9\.]+)\|([0-9]+)\|[0-9]+\|.+/i) {
		if ($2) {
			$CIDR = $1 . '/' . $MASK_BITS{$2};
		}
	}

	if ($CIDR =~ /^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\/[0-9]+$/) {
		$FLAG += 1;

		if (length($CIDR) > 15) {
			$TABS = "\t";
		}
		elsif (length($CIDR) > 11) {
			$TABS = "\t\t";
		} else {
			$TABS = "\t\t\t";
		}

		print TMP $CIDR . $TABS . "check_client_jp\n";
    }
}

print TMP "133.0.0.0/8\t\t\tcheck_client_jp\n";

close(TMP);
close(CMD);

if ($FLAG > 500) {
	system("cp $CIDR_TABLE $CIDR_TABLE.old") if -f $CIDR_TABLE;
	system("mv $CIDR_TABLE.tmp $CIDR_TABLE && postmap $CIDR_TABLE");
} else {
	unlink("$CIDR_TABLE.tmp");
}

print "Successful in update of $CIDR_TABLE.\n";

exit(0);