general-functions: add function to convert ip/mask to ip/cidr.

config/cfgroot/general-functions.pl

@@ -18,6 +18,7 @@ use strict;
 use Socket;
 use IO::Socket;
 use Net::SSLeay;
+use Net::IPv4Addr;
 
 $|=1; # line buffering
 
@@ -407,6 +408,12 @@ sub NextIP
 			     );
 }
 
+sub ipcidr
+{
+	my ($ip,$cidr) = &Net::IPv4Addr::ipv4_parse(shift);
+	return "$ip\/$cidr";
+}
+
 sub validemail {
     my $mail = shift;
     return 0 if ( $mail !~ /^[0-9a-zA-Z\.\-\_]+\@[0-9a-zA-Z\.\-]+$/ );