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# Defense in Depth - Anti-SPAM for sendmail environments   #
# by David Bank --> http://dave.trianglenug.org            #
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# Code Example #4 - Perl - MIMEDefang - filter_recipient() #
############################################################

sub filter_recipient()
	{
	# Read the parameters passed to the function
	my($recipient, $sender, $ip, $hostname, $first, $helo, $rcpt_mailer, $rcpt_host, $rcpt_addr) = @_;

	# Local variable to hold results of md_check_against_smtp_server
	my(@chk_result);

	# A HELO string for MIMEDefang to use so that log entries on the other
	#	mailserver can be distinguished as MIMEDefang checking
	my($chkhelo)="mimedefang.ourdomain.tld";

	# Search the list of our hosts using the $ip argument
	if ( exists($OurHosts{$ip}) )
		{
		# The connecting host is our own host, don't bother checking further
		return('CONTINUE', 'ok');
		}
	else
		{
		# Verify the recipient address on $rcpt_host is valid using
 		#	md_check_against_smtp_server
		@chk_result = md_check_against_smtp_server($sender, $recipient, $chkhelo, $rcpt_host);
		}

	# Return the result without interpretation
	return(@chk_result);
	}
	# End of sub filter_recipient