Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

When working with headers, remember that the current value of the header 
includes changes made during processing (such as with filter actions that add, 
remove, or modify message headings). See 

 for more information.

The following filter returns true if the headers are empty or if the headers are 
missing from the message:

EmptySubject_To_filter:

if (header('Subject') != ".") OR

   (header('To') != ".") {

   drop();

}

This filter returns true for empty Subject and To headers, but it also returns true 
for missing headers. If the message does not contain the specified headers, the 
filter still returns true. 

The 

rcpt-to

 rule selects those messages where any Envelope Recipient matches 

the given regular expression. For example, the following filter drops all messages 
sent with an email address containing the string “scarface.”

The regular expression for the 

rcpt-to

 rule is case insensitive.

scarfaceFilter:

   if (rcpt-to == 'scarface')

   {