Re: linux-ipsec: apps/utils/libs that parse IP/netbits

Going over old correspondence, I've noticed a few small loose ends in the address/subnet stuff I've done for our library, and would welcome comments on them.

Should atosubnet() look in /etc/networks if a DNS query doesn't find a name? Arguably /etc/networks is a relic of the past -- my Linux boxes don't even have such a file, and my BSD/OS box has a vestigial one -- and my feeling is that any fallback provisions for name lookup are the business of the resolver routines and /etc/resolv.conf. I'm leaning toward ignoring this.

Should non-contiguous subnet masks be rejected by atosubnet() as errors? I know of no case where they're legitimate. Is there one? I'm leaning toward outlawing them.

Should subnettoa() and related routines take a format indicator, to hedge against the possibility that we'll want different formats someday? (E.g., dotted-decimal format padded out to constant width, or reverse name lookups attempted.) It doesn't need to be anything fancy like printf; just an int that can (in future) hold a few flags or a code should suffice. I'm leaning toward doing this, out of sheer nervousness.

All comments welcome.

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