linux-ipsec: address-range syntax (was apps/utils/libs that parse...)

From: Henry Spencer <henry(at)spsystems.net>
Date: Sat Jul 18 1998 - 18:43:46 EDT

> - Pluto needs to deal with IP address ranges in the same places it

> needs to deal with subnets. Can you support them? Perhaps with
> another variant?

Good idea, and it shouldn't be difficult. However, it brings up another issue: what should the syntax be? At least some applications, e.g. Pluto, are going to want to let users write either one, and then figure out the difference by inspection.

It can't be just "start/finish"; I've thought about ways to intuit which version is meant, but they're not reliable. "start-finish" clashes with DNS name syntax, and "start:finish" clashes with IPv6 number syntax. Both "start..finish" and "start...finish" have problems with the pervasive use of dots in both names and numbers. "start,finish" looks like a list rather than a range. (Currently we don't have lists, but they might return.) "start_finish" is workable but evil.

"start--finish"? "start/-finish"? "start//finish"? None of these thrill me.

Please, somebody, think of something better. There is a strong bonus for avoiding Linux shell metacharacters (to facilitate scripting), another for being halfway intuitive and/or familiar, and a weak bonus for a small character that stands out from a line of numbers (i.e., % is not a good choice).

                                                          Henry Spencer
                                                       henry@spsystems.net
                                                     (henry@zoo.toronto.edu)

Received on Sun Jul 19 00:10:33 1998