topic Re: Application with Custom Signature & Layer 7 Processing in Custom Signatures

Application with Custom Signature & Layer 7 Processing

Emanuele — Fri, 19 Oct 2018 13:03:43 GMT

Hello All,

I have a PaloAlto PA-500 firewall on which I created my custom application based on custom signature. During the custom application creation on the Characterestics section I checked the "Continue scanning for other application" flag (refer to attached file -> CustomApplication-Characteristics.png).

I've configured a policy that allow the traffic that match my custom application and all the remaining traffic goes to default interzone policy (thus it is blocked).

As you can see from attached screenshot (refer to ShowSessionIdCommand.png) the firewall correctly identify the traffic and match my custom application (called Brass_FAB-TCP-2505-CMP).

Anyhow, I noticed that, as soon as the firewall identifies the traffic as Brass_FAB-TCP-2505-CMP, the "layer 7 processing" switch to "completed" (as shown on ShowSessionIdCommand.png) and from this moment on, within this session, any traffic flowing through the firewall will pass without any inspection.

Can you please clarify if this is the normal behaviour for the equipment or not? If yes, what is the purpose of the "Continue scanning for other application" flag?

What is the way to have the firewall continuously inspecting/analyzing the traffic that match my custom application?

Thanks all.

CustomApplication-Characteristics

ShowSessionIdCommand

Re: Application with Custom Signature & Layer 7 Processing

MP18 — Sat, 20 Oct 2018 15:31:06 GMT

my understanding is that it will continue to scan for other apps in custom app if it does not detect any other app it will

stop scanning for any other app and session is offloaded

Re: Application with Custom Signature & Layer 7 Processing

Emanuele — Mon, 22 Oct 2018 07:38:24 GMT

Thanks Mike. Can you clarify what do you mean when you say "session is offloaded"?

In addition,do you know if there is any way to maintain traffic scanning active after custom app has been detected?

@MP18 wrote:
my understanding is that it will continue to scan for other apps in custom app if it does not detect any other app it will
stop scanning for any other app and session is offloaded