I don't have the exact solution to your question because I wasn't able to see a clear solution to detecting TLS encrypted connections from the message filter/content filter viewpoint.

However, here is something that may help. You can use a combination of message filter and content filter to determine which Sender Group and Mail Flow Policy the connection came in on and apply the appropriate actions:


1. Message filter that will add the connection information.

addHeaders:
if true {
insert-header("X-SBRS", "$Reputation");
insert-header("X-MID", "$MID");
insert-header("X-Policy", "$Policy");
insert-header("X-Group", "$Group");
}


The above will add headers to the mail like this:

X-SBRS: None
X-MID: 119
X-Policy: $THROTTLED
X-Group: TLS_Required


2. Then, you can create an incoming content filter to detect the header and apply the appropriate action, whatever that may be.

Conditions (All of the following must match):
header("X-Group") == "TLS_Required"

Actions:
drop();

Hello All,

does anyone know a method of detecting TLS encrypted messages within a message filter? I would like to add a footer to all messages received over an encrypted channel. My default email policy is set to "TLS preferred".

Thanks,
Markus