On 27/10/2003, at 5:10 PM, Systems Administrator wrote:
On Mon, 27 Oct 2003, Phillip Hutchings wrote:
Slightly longer version -- some of our ISP customers are being used for relaying spam, and I'm trying to fix it.
There's a more important question here - how are they being used for spam relaying? More security is the answer, not screening the spam. If clients need to send emails from outside your network, use authenticated SMTP, not IP screening.
Doing this already.
If their computers are being used for relaying, get them to close the ports or secure their computers further.
Ports? What are ports? Secure? I just use it for e-mail? Virus checker? Well, only if it came with the computer.
:). This is an ISP. Not only that, but we specialise in users
who don't know that much about computers. So asking them to do these
things is often a problem. Likewise, if a real spammer ever signs up for
our service, I want the server to automatically prevent them from sending
any spam. My basic approach is that our users will usually do something
stupid (and someday maybe malicious), and I want to minimise the impact on
everyone else.
Ah, makes sense. You would need a courierfilter on the incoming SMTP. Check out courierperlfilter. Basically you need to pass the message through to spamassassin. Check the share/perlfilter-example.pl file for how to implement the filter, then you want something like this in the perlfilter example.
#Look for these lines:
# Here's where the custom content filter is implemented. Use filehandles
# so that cleanup's automatic.
my $fh=new IO::File "< $filename";
return "" unless defined $fh;
#and insert code replacing the while loop
my $filt = new Mail::SpamAssassin();
my $status = $spamtest->check ($mail);
if ($status->is_spam ()) {
return '550 Spam Denied';
}
return '';Probably some mistake there, but hopefully some list member will point out where.
-- Phillip Hutchings [EMAIL PROTECTED] http://www.sitharus.com/
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