Re: [exim] Refusing MAIL FROM:<> ...

Ian Eiloart wrote:
> --On 7 August 2006 09:33:29 +0100 Dave Evans
> <davide-20060629@???> wrote:
>> RFC1123:
>> The syntax shown in RFC-821 for the MAIL FROM: command omits the
>> case of an empty path: "MAIL FROM: <>" (see RFC-821 Page 15). An
>> empty reverse path MUST be supported.

Thanks. Quite far-fetched, but at least it does say MUST.

> And, while 821 omits it, 2821 doesn't:

Yes, but RFC2821 didn't copy the "MUST support" thing. (What can we
learn from this?)

> 4.5.5 Messages with a null reverse-path
> ....
> Implementors of automated email processors should be careful to make
> sure that the various kinds of messages with null reverse-path are
> handled correctly, in particular such systems SHOULD NOT reply to
> messages with null reverse-path.
>
> I think it's easy to make the case that rejecting all null-sender
> email in order to avoid some spam bounces is not being "careful to
> make sure that the various kinds of messages with null reverse-path
> are handled correctly"

Well, this heavily depends on the possible values for "correctly" in
RFC2822... >:o/

lg,
daniel