Raffael Schmid:
> Hi list
>
> Do you know whether there is a possibility to reject invalid return
> paths in postfix?
>
> The problem is, that we get spam with a header-line like the following
> and would like to reject those messages:
> Return-Path: <MAILER-DEAMON>
>
> AFAIK the return-path above is invalid, as there is only the following
> formats allowed:
> Return-Path: <john....@example.org>
> Return-Path: <>
>
> As I did not find a option in postfix to reject those mails, i could
> write a header check with pcre. But before I will do this, I'd like to
> verify whether there is really no option in postfix to set this?
Postfix has no "enforce RFC 100%" option. In particular, the address
parser must tolerate errors. Unlike a compiler such as GCC, Postfix
cannot abort on incorrect syntax, or throw away all the input that
it can't understand, therefore it cannot be implemented with a
parser that strictly goes by the rules of the grammar. Adding a
check for every possible violation is not practical, therefore
Postfix has explicit checks only for the most common violations.
Wietse
