Files
oddmuse/scripts/ip-to-regexp.pl
Alex Schroeder 4d6882ffc7 ip-to-regexp.pl: new command line script
Helps to block entire IP blocks.
2020-05-27 07:51:56 +02:00

95 lines
2.3 KiB
Perl

use Modern::Perl;
use Net::Whois::Parser qw/parse_whois/;
sub main {
my $ip = shift(@ARGV);
die "Provide an IP number as argument.\n" unless $ip;
print get_regexp_ip(get_range($ip)), "\n";
}
sub get_range {
my $ip = shift;
my $response = parse_whois(domain => $ip);
my $re = '(?:[0-9]{1,3}\.){3}[0-9]{1,3}';
my ($start, $end) = $response->{inetnum} =~ /($re) *- *($re)/;
return $start, $end;
}
sub get_groups {
my ($from, $to) = @_;
my @groups;
if ($from < 10) {
my $to = $to >= 10 ? 9 : $to;
push(@groups, [$from, $to]);
$from = $to + 1;
}
while ($from < $to) {
my $to = int($from/100) < int($to/100) ? $from + 99 - $from % 100 : $to;
if ($from % 10) {
push(@groups, [$from, $from + 9 - $from % 10]);
$from += 10 - $from % 10;
}
if (int($from/10) < int($to/10)) {
if ($to % 10 == 9) {
push(@groups, [$from, $to]);
$from = 1 + $to;
} else {
push(@groups, [$from, $to - 1 - $to % 10]);
$from = $to - $to % 10;
}
} else {
push(@groups, [$from - $from % 10, $to]);
last;
}
if ($to % 10 != 9) {
push(@groups, [$from, $to]);
$from = 1 + $to; # jump from 99 to 100
}
}
return \@groups;
}
sub get_regexp_range {
my @chars;
for my $group (@{get_groups(@_)}) {
my ($from, $to) = @$group;
my $char;
for (my $i = length($from); $i >= 1; $i--) {
if (substr($from, - $i, 1) eq substr($to, - $i, 1)) {
$char .= substr($from, - $i, 1);
} else {
$char .= '[' . substr($from, - $i, 1) . '-' . substr($to, - $i, 1). ']';
}
}
push(@chars, $char);
}
return join('|', @chars);
}
sub get_regexp_ip {
my ($from, $to) = @_;
my @start = split(/\./, $from);
my @end = split(/\./, $to);
my $regexp = "^";
for my $i (0 .. 3) {
if ($start[$i] eq $end[$i]) {
$regexp .= $start[$i];
} elsif ($start[$i] eq '0' and $end[$i] eq '255') {
last;
} elsif ($start[$i + 1] > 0) {
$regexp .= '(' . $start[$i] . '\.('
. get_regexp_range($start[$i + 1], '255') . ')|'
. get_regexp_range($start[$i] + 1, $end[$i + 1]) . ')';
$regexp .= '\.';
last;
} else {
$regexp .= '(' . get_regexp_range($start[$i], $end[$i]) . ')$';
last;
}
$regexp .= '\.' if $i < 3;
}
return $regexp;
}
main();