Re: Bypassing spam checking when using Postfix

[Daryl C. W. O'Shea]

Gareth wrote:
I use Suse Openexchange as our mail server and I have amavis installed
for virus scanning and spamassassin.
I have a problem where when people send mail using SMTP Auth
spamassassin penalises them because they are sending from a dynamic IP
address etc...
Currently I am having to whitelist their addresses which also allows
some spam through.
 

These are dynamic blocks you don't control, right?  If you do control 
them, you can just add them to your trusted/internal networks.

How do other people get around this problem?
I can't see a way of getting Postfix to add a custom header for email
received via SMTP Auth. If I could do this then I could write a custom
spamassassin rule to whitelist these emails.
 

If Postfix can be made to add, or already does add, RFC 3848 header 
'with' tokens, new versions of SA (3.0.2 and on) will fix your problem.  
Until then you can use this patch:  
http://bugzilla.spamassassin.org/attachment.cgi?id=2547&action=view

If it doesn't add these tokens (such as 'with esmtpa') could you send me 
a copy of an authenticated received header generated by Postfix?

I am currently looking into having TLS configured in Postfix listening
on a different port which sends the mail to a second copy of amavis
which when it finishes sends it back to postfix without going via
spamassassin. This just seems a bit over complicated.
 

If you've only got the one server that's pretty much your only choice, 
if the above patch won't solve the problem, (unless you can make Postfix 
add a header for auth'd connections, in which case you can write a rule 
to catch it).

Daryl