[ On Saturday, July 3, 2004 at 12:15:32 (-0700), Avleen Vig wrote: ]
> Subject: Re: [Exim] Rfc 2821 par 4.1.4 is this still valid or was it replace.
>
> On Sat, Jul 03, 2004 at 02:56:40PM -0400, Greg A. Woods wrote:
> > The SMTP client "MUST" give its proper canonical hostname in the
> > HELO/EHLO greeting (or a valid address literal). It "MUST NOT" lie and
> > give some other name which does not resolve to the address it connects
> > from.
>
> That's a fantastic interpretation of 2821.
> 3.6:
> - The domain name given in the EHLO command MUST BE either a
> primary host name (a domain name that resolves to an A RR) or,
> if the host has no name, an address literal as described in
> section 4.1.1.1.
>
> It says nothing about resolving correctly as a PTR.
1. Who the hell said anything about a PTR?!?!?!? I certainly did not.
Please try to read what I write, not what you think I wrote. It's
right there above in whatever colours your viewing device presents it
to you in.
"canonical hostname that resolves to the address it connects from"
is, in this context, entirely equivalent to "a domain name which that
resolves to an A RR ... [that] corresponds to the IP address of the
client."
2. You cannot, and MUST NOT interpret a single phrase, sentence, or
section, of any RFC on its own -- or even any whole RFC on its own.
You _MUST_ consider the whole body of relevant work, and do so in the
right context. Why does this seem so bloody hard for some people to
understand?
I.e. go read RFC 1123 too but before doing so make sure you
understand the intended meaning of phrases and words such as "host
domain name", "primary", "principle", "canonical" and so on.
3. Please learn the true purpose of the HELO/EHLO greeting
(i.e. including the 220 banner that preceeds it) before you go on
trying to debate the legal syntax and values for these things.
Unless and until you understand the "why" it's pointless to debate
the "what" and "how".
--
Greg A. Woods
+1 416 218-0098 VE3TCP RoboHack <woods@???>
Planix, Inc. <woods@???> Secrets of the Weird <woods@???>
