Configure GTP Stateful Inspection

Enable GTP Security.
Log in to the firewall web interface.
Select
Device
Setup
Management
General Settings
. Select
GTP Security
.
Click
OK
.
Commit
the change.
Select
Device
Setup
Operations
and
Reboot Device
.
Enabling or disabling GTP Security requires a commit and a reboot; the best practice is to commit and reboot at this point. After you enable GTP Security, the options for configuring and monitoring GTP traffic become available on the firewall. If you disable GTP Security, you must also Commit your change and reboot the firewall. After you disable GTP Security, the firewall does not perform GTP stateful inspection, but still checks GTP packets against Security policy rules and still applies App-ID.
(
Optional
) You can gracefully enable GTP stateful inspection to minimize disruption when you deploy a new firewall or migrate GTP traffic.
Access the CLI.
>
set gtp nodrop yes
The firewall continues to perform GTP stateful inspection and generate logs, but won’t drop GTPv2, GTPv1-C, or GTP-U packets that fail GTP stateful inspection. When you later decide to re-enable the firewall to drop packets that fail GTP stateful inspection, use the CLI operational command:
set gtp nodrop no
(this is the default setting).
>
show gtp info
The firewall displays whether GTP stateful inspection is gracefully enabled (
gtp no drop: True
) or not (
gtp no drop: False
).
Create a GTP Protection profile to inspect GTP traffic.
Select
Objects
Security Profiles
GTP Protection
and
Add
a new profile.
Give the profile a descriptive
Name
.
If the firewall is in Multiple Virtual System Mode, enable the profile to be
Shared
by all virtual systems.
Set up GTP Protection Profile for the GTP version(s) you want to inspect and configure the available options for filtering, overbilling protection, and logging GTP messages for your compliance and troubleshooting needs.
Create a Security policy rule to allow GTP traffic on your network.
Select

Policies

Security

and

Add

a descriptive

Name

for the rule in the

General

tab.

In the

Source

tab,

Add

the

Source Zone

.

In the

Destination

tab,

Add

the

Destination Zone

.

Restrict access to specific components in the EPC network; consider using address objects in the

Destination Address

field to enable access to specific IP addresses.

In the

Application

tab,

Add

the applications that correspond to the network services you want to safely allow. For example, select

gtp-v1

,

gtp-v2

, and

gtp-u

. Make sure to select the applications you enabled for inspection in the GTP Protection profile.

In the

Service/URL Category

tab, change the

Service

from

application-default

to

any

.

In the

Actions

tab, set the

Action

to

Allow

.

Attach the GTP Protection profile to the Security policy rule. For

Profile Type

, select

Profiles

and select the GTP Protection profile you set up earlier.

Verify that

Log at Session End

is enabled. GTP session start and GTP session end events are logged only when you enable

Log at Session Start

and

Log at Session End

in a Security policy rule. The session start and session end logs are available under

Monitor

Logs

GTP

. All other GTP events are logged based on the settings you enabled in the GTP Protection profile and are also available under

Monitor

Logs

GTP

.

By default, the log storage quota for GTP is 2% of the total log storage capacity for the firewall model. Because GTP logs are high volume, increase the log quota (

Device

Setup

Management

) or set up log forwarding to an external server.

Click

OK

.
(
Optional
) Block GTPv0 traffic coming into your network. Add a Security policy rule to deny application
gtpv0
. 3GPP recommends that a GTPv2 or GTPv1 entity that listens to the GTPv0 port should silently discard any GTPv0 messages it receives. The 3GPP Rel-8 GTPv1 specification removed support for GTPv1 to GTPv0 interworking; hence, a Palo Alto Networks firewall does not support stateful inspection of GTPv0 traffic.
Commit
your policies to the running configuration on the firewall.
Monitor GTP Traffic to verify that you set up GTP inspection effectively for your visibility and logging needs, and to view the GTP traffic in your network.