added netmask support

1 files changed, 63 insertions, 0 deletions

diff --git a/local/netmask.pm b/local/netmask.pm
new file mode 100644
index 0000000..8a651b0
--- /dev/null
+++ b/local/netmask.pm
@@ -0,0 +1,63 @@
+package local::netmask;
+require Exporter;
+use strict;
+use local::db;
+use base "Exporter";
+
+sub new
+{
+  my $invocant = shift;
+  my $class = ref($invocant) || $invocant;
+  # my $self  = $class->SUPER::new(@_);
+  my $self=bless {}, $class;
+  return $self;
+}
+
+sub check_ip_in_subnet
+{
+  my $self=shift;
+	my ($ip,$subnet_ip,$netmask) = @_; # example 192.168.1.1, 192.168.1.0, 24 -> returns true (1)
+	if ($ip =~ /\./ and $subnet_ip =~ /\./)
+	{ 
+	  #ipv4
+
+		my $ip_int  = $self->v4_array_to_int(split(/\./,$ip));
+		my $subnet_ip_int = $self->v4_array_to_int(split(/\./,$subnet_ip));
+
+    my @netmask_ary;
+		for my $i (0..3)
+		{
+      my $bits =  $netmask - $i*8;
+			$bits = 8 if $bits >8;
+			$bits = 0 if $bits <0;
+			my $unset = 8-$bits;
+      push @netmask_ary,256- (2** $unset  ) ;
+		}
+    my $netmask_int = $self->v4_array_to_int(@netmask_ary);
+		return 1 if ( ($ip_int & $netmask_int) == ($subnet_ip_int & $netmask_int));
+    return 0;
+	} elsif ($ip =~ /\:/ and $subnet_ip =~ /\:/) {
+	  #ipv6
+		die "Only Subnet lengths of a multiple of 16 are currently supported" if $netmask % 16;
+		my @ip = split(/\:/,$ip);
+		my @netmask = split(/\:/,$subnet_ip);
+    for my $i (1..$netmask /16)
+		{
+      my $ip_part = shift @ip;
+			$ip_part = 0 if not $ip_part;
+			my $netmask_part = shift @netmask;
+			$netmask_part = 0 if not $netmask_part;
+			return 0 if $netmask_part != $ip_part;
+		}
+		return 1;
+  } else {
+    return; # not matching or unknown
+	}
+}
+
+sub v4_array_to_int
+{
+  my $self=shift;
+	my @array=@_;
+	return unpack( "N", pack( "C4",@array ) );
+}