[6bone] Re: reverse 6dns painful (was Re: reverse DNSconsideredpointless)

[pasky at xs26.net (Petr Baudis)]

Dear diary, on Sat, Feb 14, 2004 at 09:13:06PM CET, I got a letter,
where Ben Winslow <rain@bluecherry.net> told me, that...
..snip..
> In the present-day situation, I would wager that most applications will
> deal gracefully with any 8-bit character in DNS labels, but there are
> definitely applications and resolvers still in use that do not.  I have
> not seen an application that outright *breaks* if an non-recommended
> printable char (like / or _) is used in a hostname in quite some time
> (the closest contender being Squid, which has (had?) a configuration
> option to make it fail on such hostnames.

I guess that most ircds perform quite strict checks on the hostnames
they resolve, and just throw away any even slightly suspicious.

Besides, I think that you could run into problems in URLs (probably
currently by far the most common hostname usage case). Certainly if you
use '/', ':' or '@' in the hostname, you're done, game over. And I think
that '%', '?' and '&' wouldn't be looked upon kindly by some URL
parsers.

Oh and you could run into interesting things when using ie. '*' or ' '
in a hostname ;-).

Kind regards,

-- 
				Petr "Pasky" Baudis
Stuff: http://pasky.or.cz/
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore all
progress depends on the unreasonable man. -- George Bernard Shaw