Add functionality for whitelisting single addresses or network ranges.

[people/stevee/guardian.git] / modules / Base.pm

diff --git a/modules/Base.pm b/modules/Base.pm
index 96ea2562f8dc22f6f83229c290ced65633f42381..194cb9692a62cb115f44b22dfc8a905847706403 100644 (file)
--- a/modules/Base.pm
+++ b/modules/Base.pm
@@ -135,6 +135,60 @@ sub IsValidAddressOrNetwork ($) {
        return 1;
 }
 
+#
+## Address/Network to binary format caluculator function.
+#
+## This function is used to convert a given single IP address
+## or network into a binary format.
+#
+## The used Net::IP module is not able to directly detect
+## single addresses or network ranges. Only an element which may be
+## a single address or a whole network can be assigned, for which a
+## lot of different values can be calculated. In case the input has
+## been a single address, the module will calculate the same binary
+## address (intip) and last address for the network range (last_int)
+## because internally it uses a /32 bit prefix for IPv4 and a /128 prefix
+## on IPv6 addresses.
+#
+## So a single address can be detected by just comparing both calculated
+## addresses if they are equal.
+#
+sub IPOrNet2Int($) {
+       my $address = shift;
+
+       # Assign and validate the given address, or directly return
+       # nothing (False) and exit the function.
+       my $ip = new Net::IP ($address) || return;
+
+       # Convert the given address into integer format.
+       my $first .= $ip->intip();
+
+       # Calculate last address for the given network.
+       my $last .= $ip->last_int();
+
+       # Check whether the first address equals the last address.
+       # If this is true, a single IP address has been passed.
+       if ($first eq $last) {
+               # Return the binary converted single address.
+               return $first;
+       }
+
+       # If both addresses are not equal a network has been passed.
+       #
+       # Check if the converted first address is less than the calculated last
+       # address of the network.
+       elsif ($first < $last) {
+               # Return the binary converted first and last address of
+               # the given network.
+               return $first, $last;
+       }
+
+       # If we got here, something strange happend, return nothing (False).
+       else {
+               return;
+       }
+}
+
 #
 ## Function for fileposition initialization.
 #