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Re: clarification re 2821, s4.1.4

2002-08-17 09:27:24


on 8/17/2002 5:19 AM Kai Henningsen wrote:


The other way of reading it says that an identifier which has been
verified as wrong can be rejected.

I do not see how you can justify that reading

What it says is that I cannot "refuse to accept [...] if verification
fails". It does not mention rules for when verification has succeeded,
especially in the negative form. I know that localhost is 127.0.0.1. Any
other address which claims to be localhost can be verified as incorrect.
The spec doesn't address that branch in the logic tree, thus my request
for clarification.

Separately, avoiding transfer loops by rejecting mail which appears to be
coming from the local MTA (or claims to be anyway) seems to be a good
idea, regardless of whether the identifier has been verified or not.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/