NAME

FreeMail - check message headers/body for freemail-domains

SYNOPSIS

If for example From-address is freemail, and Reply-To or address found in mail body is different freemail address, return success. Good sign of Nigerian scams etc. Test idea from Marc Perkel.

Also separate functions to check various portions of message for freemails.

CONFIGURATION

freemail_domains domain ...

   List of domains to be used in checks.

   Regexp is not supported, but following wildcards work:

   ? for single character (does not match a dot)
   * for multiple characters (does not match a dot)

   For example:
   freemail_domains hotmail.com hotmail.co.?? yahoo.* yahoo.*.*

freemail_whitelist email/domain ...

   Emails or domains listed here are ignored (pretend they aren't
   freemail). No wildcards!

freemail_import_whitelist_auth 1/0

   Entries in whitelist_auth will also be used to whitelist emails
   or domains from being freemail.  Default is 0.

freemail_import_def_whitelist_auth 1/0

   Entries in def_whitelist_auth will also be used to whitelist emails
   or domains from being freemail.  Default is 0.

header FREEMAIL_REPLYTO eval:check_freemail_replyto(['option'])

   Checks/compares freemail addresses found from headers and body.

   Possible options:

   replyto      From: or body address is different than Reply-To
                (this is the default)
   reply        as above, but if no Reply-To header is found,
                compares From: and body

header FREEMAIL_FROM eval:check_freemail_from(['regex'])

   Checks all possible "from" headers to see if sender is freemail.
   Uses SA all_from_addrs() function (includes 'Resent-From', 'From',
   'EnvelopeFrom' etc).

   Add optional regex to match the found email address(es). For example,
   to see if user ends in digit: check_freemail_from('\d@')

   If you use multiple check_freemail_from rules with regexes, remember
   that they might hit different emails from different heades. To match
   a certain header only, use check_freemail_header.

header FREEMAIL_HDRX eval:check_freemail_header('header' [, 'regex'])

   Searches defined header for freemail address. Optional regex to match
   the found address (like in check_freemail_from).

header FREEMAIL_BODY eval:check_freemail_body(['regex'])

   Searches body for freemail address. With optional regex to match.

CHANGELOG

 1.996 - fix freemail_skip_bulk_envfrom
 1.997 - set freemail_skip_when_over_max to 1 by default
 1.998 - don't warn about missing freemail_domains when linting
 1.999 - default whitelist undisclosed-recipient@yahoo.com etc
 2.000 - some cleaning up
 2.001 - fix freemail_whitelist
 2.002 - _add_desc -> _got_hit, fix description email append bug
 2.003 - freemail_import_(def_)whitelist_auth