Re: empty quoted strings and other oddities

Keith Moore <moore@cs.utk.edu> Wed, 02 October 2002 12:26 UTC

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From: Keith Moore <moore@cs.utk.edu>
To: ietf-822@imc.org
Subject: Re: empty quoted strings and other oddities
In-reply-to: (Your message of "Wed, 02 Oct 2002 06:37:20 EDT.") <3D9ACC60.30701@alex.blilly.com>
Date: Wed, 02 Oct 2002 08:26:10 -0400
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> >>Likewise, a domain literal can consist solely of the
> >>square brackets.
> > 
> > 
> > so? there are lots of addresses which are valid syntax but
> > not valid because the domain is not defined or the IP
> > address (in the domain literal) does not exist or is not
> > assigned to a host.
> 
> I'm not sure that there aren't MTAs or MUAs that would
> break or pass bizarre requests to DNS when trying to
> deal with [] as a domain literal.

if the M*A fails to deliver the message because of "no such host"
or some similar reason, that's fine.  if the M*A fails claiming
that the address is invalid syntax, it's broken.
not that this bug is likely to make a difference in practice...

> Also, in this case 2822 seems to be alone in permitting
> that syntax, which is not permitted by 2821 or 1123.

well, what is valid for the message format is not necessarily
valid for SMTP - since the message format is transport-independent
while SMTP is associated with specific transports.