Re: Mandatory From field, anonymity, and hacks

On Mon, 26 Jul 2004 23:16:57 -0400, Bruce Lilly <blilly(_at_)erols(_dot_)com> 
wrote:

> Charles Lindsey wrote:
>
> [Concerning RFC 2606]
>
> > That says "can be used for private testing..., example in documentation,
> > DNS related experimentation, invalid DNS names, or other similar uses".  
> > I
> > think that is wide enough to cover the intended usage.
> DNS experimentation and testing are different matters from deliberate
> obfuscation (or worse).
Indeed, but "invalid DNS names" means, er, "invalid DNS names", and "other  
similar uses" should cover most other applications.
And if you read further down in RFC 2606 (I don't have the exact words in  
front of me), you will see that it is recommended for use when you want  
something that is immediately and obviously invalid, just from a casual  
inspection, which is exactly what is needed in the case under discussion.
>
> Well, I might be inclined to prefer using a fixed, guaranteed black-hole
> valid address if somebody wants to set one up...
It doesn't need setting up. The TLD ".invalid" already has the required  
property, and is registered with IANA as being guaranteed never to resolve  
to anything.
> >     From: Joe Doe <jdoe(_at_)REMOVE-THIS(_dot_)foo(_dot_)com(_dot_)invalid>
> >
> > which can be aborted at once without any DNS search at all?
> Gack. NOOOOO!  Please tell me you didn't just say what I think you said!
> In such a case, the only reasonable behavior is to query DNS for an MX
> record for "REMOVE-THIS.foo.com.invalid." [*].
No, I meant exactly what I said. If it is guaranteed, by IANA  
registtration, that ".invalid" will never resolve, then agents need not  
bother to try it.
Naturally if they do (whether for testing or anything else), they will  
still be told the same thing.
> Now consider an alternative to either:
> -------------------
> Subject: foo
> Date: 1 Jan 2005 12:34:56 +0700
>
> [body] I, Joe Doe, of Timbuktu (not to be confused with any other "Joe  
> Doe"),
> being of paranoid mind, do hereby write:  blah, blah, blah.
And do you think Joe Doe is ever going to do that, when he can more easily  
write (and his readers will more easily recognize, and followup/reply  
agents can more easily generate attribution lines for)
    From: Joe Doe <jdoe(_at_)REMOVE-THIS(_dot_)foo(_dot_)com(_dot_)invalid>

Indeed, From lines of that form are already becoming quite common on  
Usenet, and if you think you can stop them, then you are just pissing in  
the wind.
--
Charles H. Lindsey ---------At Home, doing my own  
thing------------------------
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