[Mimedefang] read domain list from config file

[Kris Deugau]

Marcus Schopen wrote:
z> for some of my domains I'd like to reject mails at a given spamscore of
>> =5. For some other domains at a higher score. Is it a good idea to read
> those domain names from different "external" config file instead of
> coding them hard into mimedefang-milter?

I did this a number of years ago, using a BerkeleyDB tied hash:

sub filter_initialize {
  require DB_File;
  use Fcntl;
  tie %hosteddomains, "DB_File", "/etc/mail/hosteddomains.db", O_RDONLY;
} # filter_initialize

sub filter_cleanup {
  untie %hosteddomains;
}

And to modify your code below:

> sub filter_end {
> [...]
>   if (exists $hosteddomains{$Domain} && $hits >= 5) {
>          if ($WasResent) {
>               action_discard();
>          } else {
>               action_bounce("Recipient refuses mail due to ..."); 
>         }
>   }
> [...]

It worked pretty well.

I used the value in the hash to drive in filter_end to indicate:
 - whether or not to call ClamAV or SpamAssassin
 - to set a custom threshold at which to redirect mail instead of
delivering it to the Inbox (diverted mail got dropped in spam@<domain>
instead of the original receipient(s) inbox(es))
 - to determine whether to munge the Subject on tagged mail or not

-kgd