SA 3.1.3 + DCC 1.3.

Vernon Schryver
Wed Oct 25 14:54:22 UTC 2006

> From: Gary Mills 

> >   3. If the local whiteclnt file whitelist a mail message, should the
> >     X-DCC header say so?  Except for upward compatibility worries, I think
> >     so.  I'm thinging of making the X-DCC header be something like this
> >     in that case:
> > 
> >        X-DCC--Metrics: - 0; ok Body=0 Fuz1=0 Fuz2=0

> The absence of an X-DCC header on whitelisted messages has been a
> constant source of confusion here.  People think that DCC somehow
> skipped that message.  It would be quite helpful if people could
> tell when a message was whitelisted.  Rather than overloading the
> `X-DCC-*-Metrics' header though, I'd recommend using a new one that
> still begins with `X-DCC-*-'.  As well, it should clearly say that
> the message was whitelisted.  `0' means nothing to most people.

Why a completely different X-* header?  If that's really desirable, I
don't much mind the extra code.  (I agree that putting the brand name
in the field name of the header was a mistake.  For that matter, the
brand name was a mistake.  The use of the DCC didn't turn out as expected,
with servers all in the hands of DCC service providers.)

The '0' server-ID is not significant; it's the "ok" that matter.  In
certain rare error cases now, the DCC client client emits headers like
    X-DCC-brand-Metrics:  0; Body=0
with a missing DCC client host name and bogus server-ID of 0.  I've
changed and extended that case of X-DCC-*-Metrics header to include
the client host name and to cover cases where the DCC server failed
to answer but the local whiteclnt files blacklist the message with:

    X-DCC-brand-Metrics: clientname 0; bulk Body=many

I figured that would still be matched by SpamAssassin and other patterns
that look for "bulk" or "many".

The smallest change to cover whiteclnt blacklisting seemed to be
to replace "bulk" with "ok". 

For whitelisting, would "OK" be beter than "ok"?  If all else were
equal, I'd rather not add more pollution to the X-* namespace of SMTP

Vernon Schryver

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