postfix & fetchmail (not flushed)

Hi out there,

i've running Postfix as MTA and fetchmail to get mails from my ISP
(t-online). Trying to prevent getting spam i have included some rules in
Postfix.
in body_checks.regexp i have somthing like this:
/name=\"(.*)\.(bat|chm|cmd|com|do|exe|hta|jse|rm|sc r|pif|vbe|vbs|vxd|xl)\"$/
REJECT Attachments dieses Dateiformats nehmen wir aus
Sicherheitsgruenden nicht an

Postfix sends fetchmail the code 450 and I would expect that fetchmail
discards the mail if I start fetchmail with the following options:
fetchmail -F -L /var/log/fetchmail -Z 450,554

But this doesn't work. fetchmail always says "...not flushed". Why ?

These mails will still be left at my ISP-Account.
What i am missing?
THX 4 any hint.

Stefan

On Wed, 11 Aug 2004 11:36:31 +0200, Stefan Wegner <steve.w@t-online.de> wrote in <ef5pu1-oaq.ln1@000540086477320040390001.home.t-online.de>:

> i've running Postfix as MTA and fetchmail to get mails from my ISP
> (t-online). Trying to prevent getting spam i have included some rules in
> Postfix.
> in body_checks.regexp i have somthing like this:
> /name=\"(.*)\.(bat|chm|cmd|com|do|exe|hta|jse|rm|sc r|pif|vbe|vbs|vxd|xl)\"$/
> REJECT Attachments dieses Dateiformats nehmen wir aus
> Sicherheitsgruenden nicht an

If you are using fetchmail, I would recommend DISCARD above REJECT,
because REJECT only makes sense when a mailserver is connecting directly
to your machine. That mailserver (or spammer) will then handle the reject
message. If it's legitimate mail, that person will get a message. If it's
spam, nothing will happen. But with fetchmail, instead of the real sending
machine, it's your server that has to deal with deciding what to do. It
will generate a bounce message and send it to what it presumes is the
sender. If it's spam, that sender is probably fake, so you might be
sending the bounce to an innocent person, or a non-existent address.

If you change REJECT to DISCARD, fetchmail will deliver it and the message
will disappear, and no unnecessary bounce messages will be generated.

--
Kind regards,

Michel Klijmij
ICQ/MSN in headers http://michel.klijmij.net/

Michel Klijmij schrieb:

....
> If you change REJECT to DISCARD, fetchmail will deliver it and the message
> will disappear, and no unnecessary bounce messages will be generated.
>

OK, should work, but as i understood man fetchmail I can decide on what
SMTP-Errors (with the option -Z 450) fetchmail(!) will discard the mail
without handing it over to Postfix. Postfix only sends the code to
fetchmail so that fetchmail knows how to handle this mail.
Am i right ?

Anyway your hint (DISCARD instaed of REJECT) should work for me, cause I
dont want these attachments ever.
Stefan

On Thu, 12 Aug 2004 20:16:29 +0200, Stefan Wegner <steve.w@t-online.de>
wrote in <8aosu1-5ta.ln1@000540086477320040390001.home.t-online.de>:

> Michel Klijmij schrieb:
>
> ...
>> If you change REJECT to DISCARD, fetchmail will deliver it and the message
>> will disappear, and no unnecessary bounce messages will be generated.
>>
>
> OK, should work, but as i understood man fetchmail I can decide on what
> SMTP-Errors (with the option -Z 450) fetchmail(!) will discard the mail
> without handing it over to Postfix.

I've looked, and it should if postfix returns 450. But with reject, it
probably gives 550 or 554. Have you checked the actual error code postfix
gives?

If fetchmail doesn't, then that's a fetchmail problem, not a postfix one I
think.

--
Kind regards,

Michel Klijmij
ICQ/MSN in headers http://michel.klijmij.net/