Cisco Cisco Email Security Appliance C160 Mode D'Emploi
9-23
Cisco AsyncOS 8.5.6 for Email User Guide
Chapter 9 Using Message Filters to Enforce Email Policies
Message Filter Rules
•
•
True Rule
The
true
rule matches all messages. For example, the following rule changes the IP interface to external
for all messages it tests.
Valid Rule
The
valid
rule returns false if the message contains unparsable/invalid MIME parts and true otherwise.
For example, the following rule drops all unparsable messages it tests.
Subject Rule
The
subject
rule selects those messages where the value of the subject header matches the given regular
expression.
For example, the following filter discards all messages with subjects that start with the phrase
Make
Money...
You can specify non-ASCII characters to search for in the value of the header.
externalFilter:
if (true)
{
alt-src-host('external');
}
not-valid-mime:
if not valid
{
drop();
}
scamFilter:
if (subject == '^Make Money')
{
drop();
}