[Dovecot] mime support for pigeonhole

[Robert Schetterer]

Am 06.02.2014 10:41, schrieb Tim Dickson:
> On 05/02/2014 03:50, LuKreme wrote:
>> On 30 Jan 2014, at 11:50 , Tim Dickson <dickson.tim at googlemail.com>
>> wrote:
>>
>>> I am trying to filter mail with .exe and .zip attachments, to no
>>> success.
>> Are you using postfix with dovecot?
> I am, (standard slackware) but I will be moving to dovecot-lda so that I
> can use sieve and imap with maildirs instead of mbox.
>>   $ cat mime_headers.pcre
>> /^\s*Content-(Disposition|Type).*name\s*=\s*"?(.*\.(ade|adp|bas|bat|chm|cmd|com|cpl|crt|dll|exe|hlp|hta|inf|ins|isp|js|jse|lnk|mdb|mde|mdt|mdw|msc|msi|msp|mst|nws|ops|pcd|pif|prf|reg|scf|scr\??|sct|shb|shs|shm|swf|vb[esx]?|vxd|wsc|wsf|wsh))(\?=)?"?\s*(;|$)/x
>> REJECT Attachment name "$2" may not end with ".$3”
>>   $ grep mime main.cf
>> mime_header_checks = pcre:$config_directory/mime_headers.pcre
>>
>>
>>
> Very useful blocking filter, many thanks.
> Does it generate backscatter.?

No , should reject at smtp income data stage, but look

http://www.postfix.org/header_checks.5.html

for more info

> I have come across a number of spam emails which have more than one
> address in the from field. Would this filter send the spam to those
> addresses by way of a mail bounce.?

not sure if i understand...
if it rejects at income smtp data stage, recipients are not a matter of
interest

> 
> The main reason for the filtering is because our broadband data
> allowance was maxed out due to spam, malware spam and backscatter. I am
> having to move my mail server functionality off-site and filter it on a
> vps running slackware, dovecot and pigeonhole, before collecting it per
> mailbox via my internal server.

you should integrate clamav with sanesecurity antispam, and spamassassin
and/or amavis, take the questions to the amamvis postfix list, questions
fot filter sieve tagged mails go to dovecot list
or have a look at

http://wiki2.dovecot.org/Pigeonhole/Sieve/Examples


Best Regards
MfG Robert Schetterer

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