Local-In policies

On the FortiGate unit, there are a number of protocols and traffic that is specific to the internal workings of FortiOS. For many of these traffic sources, you can identify a specific port/IP address for this self-originating traffic. The following traffic can be configured to a specific port/IP address:

• SNMP l Syslog l alert email l FortiManager connection IP l FortiGuard services l FortiAnalyzer logging
• NTP l DNS
• Authorization requests such as RADIUS
• FSSO

Security policies control the flow of traffic through the FortiGate unit. The FortiGate unit also includes the option of controlling internal traffic, that is, management traffic.

Each interface includes an allow access configuration to allow management access for specific protocols. Local policies are set up automatically to allow all users all access. Local-in policies takes this a step further, to enable or restrict the user with that access. This also extends beyond the allow access selection.

Local-in policies are configured in the CLI with the commands:

config firewall local-in-policy edit <policy_number> set intf <source_interface> set srcaddr <source_address> set dstaddr <destination_address> set action {accept | deny} set service <service name> set schedule <schedule_name> set comments <string>

end

For example, you can configure a local-in policy so that only administrators can access the FortiGate unit on weekends from a specific management computer at 192.168.21.12, represented by the address object mgmtcomp1, using SSH on port 3 (192.168.21.77 represented by the address object FG-port3) using the Weekend schedule which defines the time the of access.

config firewall local-in-policy edit <1> set intf port3 set srcaddr mgmt-comp1 set dstaddr FG-port3 set action accept set service SSH set schedule Weekend

end

You can also disable a policy should there be a requirement to turn off a policy for troubleshooting or other purpose. To disable a policy enter the commands:

Security policy 0

config firewall local-in-policy edit <policy_number> set status disable

end

Use the same commands with a status of enable to use the policy again.

It is also an option to dedicate the interface as HA management interface by using the setting: set ha-mgmt-intf-only enable

Local-in policies are also supported for IPv6 by entering the command: config firewall local-in-policy6.

While there is a section under Policy & Objects for viewing the existing Local In Policy configuration, policies cannot be created or edited here in the GUI. The Local In polices can only be created or edited in the CLI.

GUI and CLI

Now in FortiGate, there are two places that IPS can be enabled, in a firewall policy and in an interface policy. In the firewall policy implementation, IPS sensor can be configured in both CLI and GUI. When adding an IPS sensor to an interface policy it must be done through the CLI. There is no GUI input window for the “Interface Policy”. There is however, a DoS Policy section in the GUI.

Dropped, flooded, broadcast, multicast and L2 packets

In many evaluation or certification tests, FortiGate firewall is often required to log any packets dropped by the firewall. In most of cases, these packets are of invalid headers so firewall just drops them silently. It is natural to forward all these packets to IPS first so FortiGate firewall is able to generate logs for invalid packets.

Flooded, broadcast and multicast traffics do not reach any of services in the forwarding path. They can be inspected by the interface policy as long as they match the addresses defined. Potentially, L2 packets can also be sent to IPS for inspection through interface-policy, but it is not enabled in FortiOS 4.0.

Traffic destined to the FortiGate unit

IPS enabled in firewall policies can only inspect the traffic pass through FortiGate unit, not the traffic destined to FortiGate unit. Enabling IPS in interface-policy allows IPS to pick up any packet on the interface so it is able to inspect attacks targeting FGT.