Security Configuration Guide: Zone-Based Policy Firewall Cisco IOS Release 12.4T
Zone-Based Policy Firewall
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Zone-Based Policy Firewall

Contents

Zone-Based Policy Firewall

Last Updated: January 20, 2012

This module describes the Cisco IOS unidirectional firewall policy between groups of interfaces known as zones. Prior to the release of Cisco IOS unidirectional firewall policy, Cisco IOS firewalls were configured as an inspect rule only on interfaces. Traffic entering or leaving the configured interface was inspected based on the direction that the inspect rule was applied.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Prerequisites for Zone-Based Policy Firewall

  • Before you create zones, you must consider what should constitute zones. The general guideline is that you should group interfaces that are similar when they are viewed from a security perspective.
  • The Wide Area Application Services (WAAS) and Cisco IOS firewall interoperability capability applies only on the Cisco IOS Zone-Based Policy Firewall feature in Release 12.4(11)T2 and later releases. The Cisco IOS firewall that preceded Cisco IOS Release 12.4(11)T2 does not incorporate the Cisco WAAS interoperability enhancement.

Restrictions for Zone-Based Policy Firewall

  • If a configuration includes both security zones and inspect rules on interfaces (the old methodology), the configuration may work, but that type of configuration is not recommend.
  • The cumulative counters in the show policy-map type inspect zone-pair command output do not increment for match statements in a nested class-map configuration in Cisco IOS Releases 12.4(20)T and 12.4(15)T. The problem with the counters exists regardless of whether the top level class map uses the match-any or match-all keyword. For more information, see "Example Protocol Match Data Not Incrementing for a Class Map."
  • In Cisco IOS Release 12.4(15)T, if the Simple Mail Transfer Protocol (SMTP) is configured for inspection in a class map and you need to configure the Extended Simple Mail Transfer Protocol (ESMTP) for inspection, then the no match protocol smtp command must be entered before adding the match protocol smtp extended command. To revert to regular SMTP inspection, use the no match protocol smtp extended command and then enter the match protocol smtp command. If these commands are not configured in the proper order, the following error is displayed:
    %Cannot add this filter. Remove match protocol smtp filter and then add this filter.
  • In a WAAS and Cisco IOS firewall configuration, all packets processed by a Wide Area Application Engine (WAE) device must go over the Cisco IOS firewall in both directions to support the Web Cache Coordination Protocol (WCCP). This situation occurs because the Layer 2 redirect is not available in Cisco IOS Release 12.4T. If Layer 2 redirect is configured on the WAE, the system defaults to the generic routing encapsulation (GRE) redirect to continue to function.
  • When an in-to-out zone-based policy is configured to match the Internet Control Message Protocol (ICMP) on a Windows system, the traceroute command works. However, the same configuration on an Apple system does not work because it uses a UDP-based traceroute. To overcome this issue, configure an out-to-in zone-based policy with the icmp time-exceeded and icmp host unreachable commands with the pass command (not the inspect command).
  • In a WAAS and Cisco IOS firewall configuration, WCCP does not support traffic redirection using policy-based routing (PBR).
  • Stateful inspection support for multicast traffic is not supported between any zones, including the self zone. Use Control Plane Policing for protection of the control plane against multicast traffic.
  • A UDP-based traceroute is not supported through ICMP inspection.
  • To allow GRE and Encapsulating Security Payload (ESP) protocol traffic through a zone-based policy firewall, you must use the pass command. The GRE and ESP protocols do not support stateful inspection and if you use the inspect command, the traffic for these protocols is dropped.

Information About Zone-Based Policy Firewall

Top-Level Class Maps and Policy Maps

Top-level class maps allow you to identify the traffic stream at a high level. This is accomplished by using the match access-group and match protocol commands. Top-level class maps are also referred to as Layer 3 and Layer 4 class maps.

Top-level policy maps allow you to define high-level actions by using the inspect, drop, pass, and urlfilter keywords. You can attach maps to a target (zone pair).


Note


Only inspect type policies can be configured on a zone pair.

Application-Specific Class Maps and Policy Maps

Application-specific class maps allow you to identify traffic based on the attributes of a given protocol. All the match conditions in these class maps are specific to an application (for example, HTTP or SMTP). Application-specific class maps are identified by an additional subtype that generally is the protocol name (HTTP or SMTP) in addition to the type inspect.

Application-specific policy maps are used to specify a policy for an application protocol. For example, if you want to drop HTTP traffic with Unique Resource Identifier (URI) lengths exceeding 256 bytes, you must configure an HTTP policy map to do that. Application-specific policy maps cannot be attached directly to a target (zone pair). They must be configured as "child" policies in a top-level Layer 3 or Layer 4 policy map.

Overview of Zones

A zone is a group of interfaces that have similar functions or features. Zones provide a way for you to specify where a Cisco IOS firewall is applied.

For example, on a router, Gigabit Ethernet interface 0/0/0 and Gigabit Ethernet interface 0/0/1 may be connected to the local LAN. These two interfaces are similar because they represent the internal network, so they can be grouped into a zone for firewall configurations.

By default, the traffic between interfaces in the same zone is not subjected to any policy. The traffic passes freely. Firewall zones are used for security features.


Note


Zones may not span interfaces in different VPN routing and forwarding (VRF) instances.

When a zone-based policy firewall is enabled for TCP keepalive traffic and the host behind the firewall is undergoing an ungraceful disconnect, TCP keepalive works only when the configured TCP timeout is complete. On receiving an out-of-window reset (RST) packet, the firewall sends an empty acknowledge (ACK) packet to the initiator of the RST packet. This ACK has the current sequence (SEQ) and the ACK number from the firewall session. On receiving this ACK, the client sends an RST packet with the SEQ number that is equal to the ACK number in the ACK packet. The firewall processes this RST packet, clears the firewall session, and passes the RST packet.

Security Zones

A security zone is a group of interfaces to which a policy can be applied.

Grouping interfaces into zones involves two procedures:

  • Creating a zone so that interfaces can be attached to it.
  • Configuring an interface to be a member of a given zone.

By default, traffic flows among interfaces that are members of the same zone.

When an interface is a member of a security zone, all traffic (except traffic going to the router or initiated by the router) between that interface and an interface within a different zone is dropped by default. To permit traffic to and from a zone-member interface and another interface, you must make that zone part of a zone pair and apply a policy to that zone pair. If the policy permits traffic (through inspect or pass actions), traffic can flow through the interface.

Basic rules to consider when setting up zones are as follows:

  • Traffic from a zone interface to a nonzone interface or from a nonzone interface to a zone interface is always dropped; unless default zones are enabled (default zone is a nonzone interface).
  • Traffic between two zone interfaces is inspected if there is a zone-pair relationship for each zone and if there is a configured policy for that zone pair.
  • By default, all traffic between two interfaces in the same zone is always allowed.
  • A zone pair can be configured with a zone as both the source and the destination zones. An inspect policy can be configured on this zone pair to inspect or drop the traffic between two interfaces in the same zone.

A policy is applied to the initiating packet of a traffic flow. After the initial packet has been classified and permitted, traffic flows between peers with no further reclassification of the packet (this means that bidirectional traffic flow is allowed after the initial classification). If you have a zone pair between Zone Z1 and Zone Z2, and no zone pair between Zone Z2 and Zone Z1, all traffic that is initiated from Zone Z2 is blocked. Traffic from Zone Z1 to Zone Z2 is permitted or denied based on the zone pair policy.

For traffic to flow among all the interfaces in a router, all interfaces must be members of security zones or the default zone.

It is not necessary for all router interfaces to be members of security zones.

The figure below illustrates the following:

  • Interfaces E0 and E1 are members of security zone Z1.
  • Interface E2 is a member of security zone Z2.
  • Interface E3 is not a member of any security zone.
Figure 1 Security Zone Restrictions


The following situations exist:

  • The zone pair and policy are configured in the same zone. If no policy is configured for Z1 and Z2, traffic will flow freely between E0 and E1, but not between E0 or E1 to E2. A zone pair and policy may be created to inspect this traffic.
  • If no policies are configured, traffic will not flow between any other interfaces (for example, E0 and E2, E1 and E2, E3 and E1, and E3 and E2).
  • Traffic can flow between E0 or E1 and E2 only when an explicit policy permitting traffic is configured between zone Z1 and zone Z2.
  • Traffic can never flow between E3 and E0/E1/E2 unless default zones are enabled and a zone-pair is created between the default zone and the other zones.

Virtual Interfaces as Members of Security Zones

A virtual template interface is a logical interface configured with generic configuration information for a specific purpose or for a configuration common to specific users, plus router-dependent information. The template contains Cisco IOS software interface commands that are applied to virtual access interfaces. To configure a virtual template interface, use the interface virtual-template command.

Zone member information is acquired from a RADIUS server and the dynamically created interface is made a member of that zone.

The zone-member security command adds the dynamic interface into the corresponding zone.

Zone Pairs

A zone pair allows you to specify a unidirectional firewall policy between two security zones.

To define a zone pair, use the zone-pair security command. The direction of the traffic is specified by a source and destination zone. The source and destination zones of a zone pair must be security zones.

You can select the default or self zone as either the source or the destination zone. The self zone is a system-defined zone. It does not have any interfaces as members. A zone pair that includes the self zone, along with the associated policy, applies to traffic directed to the router or traffic generated by the router. It does not apply to traffic through the router.

The most common usage of firewalls is to apply them to traffic through a router, so you need at least two zones (that is, you cannot use the self zone).

To permit traffic between zone-member interfaces, you must configure a policy permitting (or inspecting) traffic between that zone and another zone. To attach a firewall policy map to the target zone pair, use the service-policy type inspect command.

The figure below shows the application of a firewall policy to traffic flowing from zone Z1 to zone Z2, which means that the ingress interface for the traffic is a member of zone Z1 and the egress interface is a member of zone Z2.

Figure 2 Zone Pairs


If there are two zones and you require policies for traffic going in both directions (from Z1 to Z2 and Z2 to Z1), you must configure two zone pairs (one for each direction).

If a policy is not configured between a pair of zones, traffic is dropped. However, it is not necessary to configure a zone pair and a service policy solely for the return traffic. By default, return traffic is not allowed. If a service policy inspects the traffic in the forward direction and there is no zone pair and service policy for the return traffic, the return traffic is inspected. If a service policy passes the traffic in the forward direction and there is no zone pair and service policy for the return traffic, the return traffic is dropped. In both these cases, you need to configure a zone pair and a service policy to allow the return traffic. In the above figure, it is not mandatory that you configure a zone pair source and destination solely for allowing return traffic from Z2 to Z1. The service policy on the Z1 to Z2 zone pair takes care of it.

Zones and Inspection

Zone-based policy firewalls examine the source and destination zones from the ingress and egress interfaces for a firewall policy. It is not necessary that all traffic flowing to or from an interface be inspected; you can designate that individual flows in a zone pair be inspected through your policy map that you apply across the zone pair. The policy map will contain class maps that specify the individual flows.

You can also configure inspect parameters like TCP thresholds and timeouts on a per-flow basis.

Zones and ACLs

Access Control Lists (ACLs) applied to interfaces that are members of zones are processed before the policy is applied on the zone pair. You must make sure that interface ACLs do not interfere with the policy firewall traffic when there are policies between zones.

Pinholes (are ports opened through a firewall that allows applications controlled access to a protected network) are not punched for return traffic in interface ACLs.

Zones and VRF-Aware Firewalls

The Cisco IOS firewall is VPN routing and forwarding (VRF)-aware. It handles IP address overlap across different VRFs, separate thresholds, and timeouts for VRFs. All interfaces in a zone must belong to the same VRF.

However, you should not group interfaces from different VRFs in the same zone because VRFs belong to different entities that typically have their own policies.

You can configure a zone pair between two zones that contain different VRFs, as shown in the figure below.

When multiple VRFs are configured on a router and an interface provides common services to all the VRFs (for example, Internet service), you should place that interface in a separate zone. You can then define policies between the common zone and other zones. (There can be one or more zones per VRF.)

Figure 3 Zones and VRF


In the figure above, the interface providing common services is a member of the zone "common." All of VRF A is in a single zone, vrf_A. VRF B, which has multiple interfaces, is partitioned into multiple zones vrf_B_1 and vrf_B_2. Zone Z1 does not have VRF interfaces. You can specify policies between each of these zones and the common zone. Additionally, you can specify polices between each of the zones vrf_A, vrf_B_n, and Z1 if VRF route export is configured and the traffic patterns make sense. You can configure a policy between zones vrf_A and vrf_B_1, but you have to make sure that traffic can flow between them.

There is no need to specify the global thresholds and timers on a per-VRF basis. Instead, parameters are supplied to the inspect action through a parameter map.

Zones and Transparent Firewalls

The Cisco IOS firewall supports transparent firewalls where the interfaces are placed in bridging mode and IP firewalling is performed on the bridged traffic.

To configure a transparent firewall, use the bridge command to enable the bridging of a specified protocol in a specified bridge and the zone-member security command to attach an interface to a zone. The bridge command on the interface indicates that the interface is in bridging mode.

A bridged interface can be a member of a zone. In a typical case, the Layer 2 domain is partitioned into zones and a policy is applied the same way as for Layer 3 interfaces.

Transparent Firewall Restriction for P2P Inspection

The Cisco IOS firewall uses network-based application recognition (NBAR) for peer-to-peer (P2P) protocol classification and policy enforcement. NBAR is not available for bridged packets; thus, P2P packet inspection is not supported for firewalls with transparent bridging.

Overview of Security Zone Firewall Policies

A class is a way of identifying a set of packets based on its contents. Normally you define a class so that you can apply an action on the identified traffic that reflects a policy. A class is designated through class maps.

An action is a specific functionality that is typically associated with a traffic class. For example, inspect, drop, and pass are actions.

To create firewall policies, you should complete the following tasks:

  • Define a match criterion (class map).
  • Associate actions to the match criterion (policy map).
  • Attach the policy map to a zone pair (service policy).

The class-map command creates a class map to be used for matching packets to a specified class. Packets arriving at the targets (such as the input interface, output interface, or zone pair), that are determined by how the service-policy command is configured, are checked against match criteria configured for a class map to determine if the packet belongs to that class.

The policy-map command creates or modifies a policy map that can be attached to one or more targets to specify a service policy. Use the policy-map command to specify the name of the policy map to be created, added to, or modified before you can configure policies for classes whose match criteria are defined in a class map.

Class Maps and Policy Maps for Zone-Based Policy Firewalls

Quality of service (QoS) class maps have numerous match criteria; firewalls have fewer match criteria. Firewall class maps have the type inspect and this information controls what shows up under firewall class maps.

A policy is an association of traffic classes and actions. It specifies what actions should be performed on defined traffic classes. An action is a specific function, and it is typically associated with a traffic class. For example, inspect and drop are actions.

Layer 3 and Layer 4 Class Maps and Policy Maps

Layer 3 and Layer 4 class maps are used to identify traffic streams on which different actions should be performed.

A Layer 3 or Layer 4 policy map is sufficient for the basic inspection of traffic.

The following example shows how to configure class map c1 with the match criteria of ACL 101 and the HTTP protocol, and create an inspect policy map named p1 to specify that packets will be dropped on the traffic at c1:

Router(config)# class-map type inspect match-all c1
 
Router(config-cmap)# match access-group 101
Router(config-cmap)# match protocol http
 
Router(config)# policy-map type inspect p1
 
Router(config-pmap)# class type inspect c1
 
Router(config-pmap-c)# drop

To create a Layer 3 or Layer 4 policy, see the "Configuring Layer 7 Protocol-Specific Firewall Policies"section.

Class-Map Configuration Restriction

If a traffic meets multiple match criteria, these match criteria must be applied in the order of specific to less specific. For example, consider the following class map example:

class-map type inspect match-any my-test-cmap
 match protocol http
 match protocol tcp

In this example, HTTP traffic must first encounter the match protocol http command to ensure that the traffic is handled by the service-specific capabilities of HTTP inspection. If the "match" lines are reversed, and the traffic encounters the match protocol tcp command before it is compared to the match protocol http command, the traffic would be classified as TCP traffic and inspected according to the capabilities of the firewall's TCP inspection component. This configuration would be a problem for services such as FTP and TFTP, and for multimedia and voice signaling services such as H.323, Real Time Streaming Protocol (RTSP), Session Initiation Protocol (SIP), and Skinny. These services require additional inspection capabilities to recognize the more complex activities.

Rate Limiting (Policing) Traffic Within a Layer 3 and Layer 4 Policy Map

In Cisco IOS Release 12.4(9)T and later releases, you can use the police command within an inspect policy to limit the number of concurrent connections allowed for applications such as Instant Messenger and P2P.

To effectively use the police command, you must enable Cisco IOS stateful packet inspection within the inspect policy map. If you configure the police command without configuring the inspect command, you will receive an error message and the police command will be rejected.

Compatibility with Existing Police Actions

Police actions provisioned in a modular QoS CLI (MQC) policy map are applied as input and output policies on an interface. An inspect policy map can be applied only to a zone pair, not to an interface. The police action will be enforced on traffic that traverses the zone pair. (The direction of the traffic is inherent to the specification of the zone pair.) Thus, a QoS policy containing a police action can be present on interfaces that make up a zone pair and a police action can be present in an inspect policy map applied across the zone pair. If both police actions are configured, the zone pair police action is executed after the input interface police action, but before the output interface police action. There is no interaction between QoS and the inspect police actions.

Police Restrictions
  • The police action is not allowed in policies that are attached to zone pairs involving a "self" zone. Use Control Plane Policing if you want to perform this task.
  • Policing can be specified only in Layer 3 and Layer 4 policy maps; it cannot be specified in Layer 7 policy maps.

Layer 7 Class Maps and Policy Maps

Layer 7 class maps can be used in inspect policy maps only for deep packet inspection (DPI). The DPI functionality is delivered through Layer 7 class maps and policy maps.

To create a Layer 7 class map, use the class-map type inspect command for the desired protocol. For example, for the HTTP protocol, enter the class-map type inspect http command.

The type of class map (for example, HTTP) determines the match criteria that you can use. For example, if you want to specify HTTP traffic that contains Java applets, you must specify a "match response body java" statement in the context of an "inspect HTTP" class map.

A Layer 7 policy map provides application-level inspection of traffic. The policy map can include class maps only of the same type.

To create a Layer 7 policy map, specify the protocol in the policy-map type inspect command. For example, to create a Layer 7 HTTP policy map, use the policy-map type inspect http policy-map-name command. Enter the name of the HTTP policy-map for the policy-map-name argument.

If you do not specify a protocol name (for example, if you use the policy-map type inspect command), you will be creating a Layer 3 or Layer 4 policy map, which can only be an inspect type policy map.

A Layer 7 policy map must be contained in a Layer 3 or Layer 4 policy map; it cannot be attached directly to a target. To attach a Layer 7 policy map to a top-level policy map, use the service-policy command and specify the application name (that is, HTTP, Internet Message Access Protocol [IMAP], Post Office Protocol 3 [POP3], Simple Mail Transfer Protocol [SMTP], or SUN Remote Procedure Call [SUNRPC]). The parent class for a Layer 7 policy should have an explicit match criterion that match only one Layer 7 protocol before the policy is attached.

If the Layer 7 policy map is in a lower level, you must specify the inspect action at the parent level for a Layer 7 policy map.

Layer 7 Supported Protocols

You can create Layer 7 class maps and policy maps for the following protocols:

  • America Online (AOL) Instant Messenger (IM) protocol
  • eDonkey P2P protocol
  • FastTrack traffic P2P protocol
  • Gnutella Version 2 traffic P2P protocol
  • H.323 VoIP Protocol Version 4
  • HTTP--The protocol used by web browsers and web servers to transfer files, such as text and graphic files
  • Internet Message Access Protocol (IMAP)--Method of accessing e-mail or bulletin board messages kept on a mail server that can be shared
  • I Seek You (ICQ) IM protocol
  • Kazaa Version 2 P2P protocol
  • MSN Messenger IM protocol
  • Post Office Protocol, Version 3 (POP3)--Protocol that client e-mail applications use to retrieve mail from a mail server
  • SIP--Session Initiation Protocol (SIP)
  • SMTP--Simple Network Management Protocol
  • SUNRPC--Sun RPC (Remote Procedure Call)
  • Windows Messenger IM Protocol
  • Yahoo IM protocol

For information on configuring a Layer 7 class map and policy map (policies), see the "Configuring Layer 7 Protocol-Specific Firewall Policies" section.

Class-Default Class Map

In addition to user-defined classes, a system-defined class map named class-default represents all packets that do not match any of the user-defined classes in a policy. The class-default class is always the last class in a policy map.

You can define explicit actions for the group of packets that do not match any of the user-defined classes. If you do not configure any actions for the class-default class in an inspect policy, the default action is drop.


Note


For a class-default in an inspect policy, you can configure only drop action or pass action.

The following example shows how to use class-default in a policy map. In this example, HTTP traffic is dropped and the remaining traffic is inspected. Class map c1 is defined for HTTP traffic, and class-default is used for a policy map p1.

Router(config)# class-map type inspect match-all c1
Router(config-cmap)# match protocol http
Router(config)# policy-map type inspect p1
Router(config-pmap)# class type inspect c1 
Router(config-pmap-c)# drop 
Router(config-pmap)# class class-default 
Router(config-pmap-c)# drop
 

Hierarchical Policy Maps

A policy can be nested within a policy. A policy that contains a nested policy is called a hierarchical policy.

To create a hierarchical policy, attach a policy directly to a class of traffic. A hierarchical policy contains a child and a parent policy. The child policy is the previously defined policy that is associated with the new policy through the use of the service-policy command. The new policy using the preexisting policy is the parent policy.


Note


There can be a maximum of two levels in a hierarchical inspect service policy.

Parameter Maps

A parameter map allows you to specify parameters that control the behavior of actions and match criteria specified under a policy map and a class map, respectively.

There are three types of parameter maps:

  • Inspect parameter map

An inspect parameter map is optional. If you do not configure a parameter map, the software uses default parameters. Parameters associated with the inspect action apply to all nested actions (if any). If parameters are specified in both the top and lower levels, the parameters in the lower levels override those in the top levels.

  • URL Filter parameter map

A parameter map is required for URL filtering (through the URL filter action in a Layer 3 or Layer 4 policy map and the URL filter parameter map).

  • Protocol-specific parameter map

A parameter map that is required for an Instant Messenger application (Layer 7) policy map.

Firewall and Network Address Translation

Network Address Translation (NAT) enables private IP internetworks that use nonregistered IP addresses to connect to the Internet. NAT operates on a router, usually connecting two networks, and translates the private (not globally unique) addresses in the internal network into legal addresses before packets are forwarded onto another network. NAT can be configured to advertise only one address for the entire network to the outside world. A router configured with NAT will have at least one interface to the inside network and one to the outside network.

In a typical environment, NAT is configured at the exit router between a stub domain and the backbone. When a packet leaves the domain, NAT translates the locally significant source address into a globally unique address. When a packet enters the domain, NAT translates the globally unique destination address into a local address. If more than one exit point exists, each NAT must have the same translation table. If the software cannot allocate an address because it has run out of addresses, it drops the packet and sends an ICMP host unreachable packet.

With reference to NAT, the term "inside" refers to those networks that are owned by an organization and that must be translated. Inside this domain, hosts will have addresses in one address space. When NAT is configured and when the hosts are outside, hosts will appear to have addresses in another address space. The inside address space is referred to as the local address space and the outside address space is referred to as the global address space.

Consider a scenario where NAT translates both the source and the destination IP addresses. A packet is sent to a router from inside NAT with the source address 192.168.1.1 and the destination address 10.1.1.1. NAT translates these addresses and sends the packet to the external network with the source address 209.165.200.225 and the destination address 209.165.200.224.

Similarly, when the response comes back from outside NAT, the source address will be 209.165.200.225 and the destination address will be 209.165.200.224. Therefore, inside NAT, the packets will have a source address of 10.1.1.1 and a destination address of 192.168.1.1.

In this scenario, if you want to create an Application Control Engine (ACE) to be used in a firewall policy, the pre-NAT IP addresses (also known as inside local and outside global addresses) 192.168.1.1 and 209.165.200.224 must be used.

WAAS Support for the Cisco IOS Firewall

The WAAS firewall software, which was introduced in Cisco IOS Release 12.4(15)T, provides an integrated firewall that optimizes security-compliant WANs and application acceleration solutions with the following benefits:

  • Optimizes a WAN through full stateful inspection capabilities.
  • Simplifies Payment Card Industry (PCI) compliance.
  • Protects transparent WAN accelerated traffic.
  • Integrates WAAS networks transparently.
  • Supports the Network Management Equipment (NME) WAE modules or standalone WAAS device deployment.

WAAS has an automatic discovery mechanism that uses TCP options during the initial three-way handshake used to identify WAE devices transparently. After automatic discovery, optimized traffic flows (paths) experience a change in the TCP sequence number to allow endpoints to distinguish between optimized and nonoptimized traffic flows.


Note


Paths are synonymous with connections.

WAAS allows the Cisco IOS firewall to automatically discover optimized traffic by enabling the sequence number to change without compromising the stateful Layer 4 inspection of TCP traffic flows that contain internal firewall TCP state variables. These variables are adjusted for the presence of WAE devices.

If the Cisco IOS firewall notices that a traffic flow has successfully completed WAAS automatic discovery, it permits the initial sequence number shift for the traffic flow and maintains the Layer 4 state on the optimized traffic flow.


Note


Stateful Layer 7 inspection on the client side can also be performed on nonoptimized traffic.

WAAS Traffic Flow Optimization Deployment Scenarios

The following sections describe two different WAAS traffic flow optimization scenarios for branch office deployments. WAAS traffic flow optimization works with the Cisco IOS firewall feature on a Cisco Integrated Services Router (ISR).

The figure below shows an example of an end-to-end WAAS traffic flow optimization with the Cisco IOS firewall. In this particular deployment, an Network Modules (NME)-WAE device is on the same router as the Cisco IOS firewall. Web Cache Communication Protocol (WCCP) is used to redirect traffic for interception.

Figure 4 End-to-End WAAS Optimization Path


WAAS Branch Deployment with an Off-Path Device

A WAE device can be either an NME-WAE that is installed on an ISR as an integrated service engine (as shown in WAAS Branch Deployment with an Off-Path Device) or a standalone WAE device.

The figure below shows a WAAS branch deployment that uses WCCP to redirect traffic to an off-path, standalone WAE device for traffic interception. The configuration for this option is the same as the WAAS branch deployment with an NME-WAE.

Figure 5 WAAS Off-Path Branch Deployment


WAAS Branch Deployment with an Inline Device

The figure below shows a WAAS branch deployment that has an inline WAE device that is physically in front of the ISR router. Because the WAE device is in front of the router, the Cisco IOS firewall receives WAAS optimized packets and hence, Layer 7 inspection on the client side is not supported.

Figure 6 WAAS Inline Path Branch Deployment


An edge WAAS device with the Cisco IOS firewall is applied at branch office sites that must inspect the traffic moving to and from a WAN connection. The Cisco IOS firewall monitors traffic for optimization indicators (TCP options and subsequent TCP sequence number changes) and allows optimized traffic to pass, while still applying Layer 4 stateful inspection and deep packet inspection to all traffic and maintaining security while accommodating WAAS optimization advantages.


Note


If the WAE device is in the inline location, the device enters its bypass mode after the automatic discovery process. Although the router is not directly involved in WAAS optimization, the router must be aware that WAAS optimization is applied to the traffic in order to apply the Cisco IOS firewall inspection to network traffic and make allowances for optimization activity if optimization indicators are present.

Out-of-Order Packet Processing Support in the Zone-Based Firewall Application

Out-of-Order (OoO) packet processing support for Common Classification Engine (CCE) firewall application and CCE adoptions of the Intrusion Prevention System (IPS) allows for packets that arrive out of order to be copied and reassembled in the correct order. The OoO packet processing reduces the need to retransmit dropped packets and reduces the bandwidth needed for transmission on a network. To configure OoO support, use the parameter-map type ooo global command.


Note


IPS sessions use OoO parameters that are configured using the parameter-map type ooo global command.

Note


OoO processing is not supported in SMTP because SMTP supports masking actions that require packet modification.

OoO packet processing support is enabled by default when a Layer 7 policy is configured for DPI for the following protocols:

  • AOL IM protocol
  • eDonkey P2P protocol
  • FastTrack traffic P2P protocol
  • Gnutella Version 2 traffic P2P protocol
  • H.323 VoIP Protocol Version 4
  • HTTP--The protocol used by web browsers and web servers to transfer files, such as text and graphic files
  • IMAP--Method of accessing e-mail or bulletin board messages kept on a mail server that can be shared
  • ICQ IM Protocol
  • Kazaa Version 2 P2P protocol
  • Match Protocol SIP--Match Protocol SIP
  • MSN Messenger IM protocol
  • POP3--Protocol that client e-mail applications use to retrieve mail from a mail server
  • SUNRPC--Sun RPC
  • Windows Messenger IM Protocol
  • Yahoo IM protocol

For information on configuring a Layer 7 class map and policy map (policies), see the "Configuring Layer 7 Protocol-Specific Firewall Policies" section.


Note


OoO packets are dropped when IPS and zone-based policy firewall with L4 inspection are enabled.

Intrazone Support in the Zone-Based Firewall Application

Intrazone support allows a zone configuration to include users both inside and outside a network. Intrazone support allows traffic inspection between users belonging to the same zone but different networks. Before Cisco IOS Release 15.0(1)M, traffic within a zone was allowed to pass uninspected by default. To configure a zone pair definition with the same zone for source and destination, use the zone-pair security command. This allows the functionality of attaching a policy map and inspecting the traffic within the same zone.

How to Configure Zone-Based Policy Firewall

Configuring Layer 3 and Layer 4 Firewall Policies

Layer 3 and Layer 4 policies are "top level" policies that are attached to the target (zone pair). Use the following tasks to configure Layer 3 and Layer 4 firewall policies:

Configuring a Class Map for a Layer 3 and Layer 4 Firewall Policy

Use this task to configure a class map for classifying network traffic.


Note


You must perform at least one match step from Step 4, 5, or 6.

When packets are matched to an access group, protocol, or class map, a traffic rate is generated for these packets. In a zone-based firewall policy, only the first packet that creates a session matches the policy. Subsequent packets in this flow do not match the filters in the configured policy, but instead match the session directly. The statistics related to subsequent packets are shown as part of the inspect action.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class-map type inspect [match-any | match-all] class-map-name

4.    match access-group {access-group | name access-group-name}

5.    match protocol protocol-name [signature]

6.    match class-map class-map-name

7.    exit

8.    show policy-map type inspect zone-pair session


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class-map type inspect [match-any | match-all] class-map-name


Example:

Router(config)# class-map type inspect match-all c1

 

Creates a Layer 3 or Layer 4 inspect type class map and enters QoS class-map configuration mode.

 
Step 4
match access-group {access-group | name access-group-name}


Example:

Router(config-cmap)# match access-group 101

 

Configures the match criterion for a class map based on the ACL name or number.

 
Step 5
match protocol protocol-name [signature]


Example:

Router(config-cmap)# match protocol http

 

Configures the match criterion for a class map on the basis of a specified protocol.

  • Only Cisco IOS stateful packet inspection-supported protocols can be used as match criteria in inspect type class maps.
  • signature--Signature-based classification for P2P packets is enabled.
 
Step 6
match class-map class-map-name


Example:

Router(config-cmap)# match class-map c1

 

Specifies a previously defined class as the match criteria for a class map.

 
Step 7
exit


Example:

Router(config-cmap)# end

 

Exits QoS class-map configuration mode and enters privileged EXEC mode.

 
Step 8
show policy-map type inspect zone-pair session


Example:

Router(config-cmap)# show policy-map type inspect zone-pair session

 

(Optional) Displays the Cisco IOS stateful packet inspection sessions created because of the policy-map application on the specified zone pair.

Note    The information displayed under the class-map field is the traffic rate (bits per second) of the traffic that belongs to the connection-initiating traffic only. Unless the connection setup rate is significantly high and is sustained for multiple intervals over which the rate is computed, no significant data is shown for the connection.
 

Creating a Policy Map for a Layer 3 and Layer 4 Firewall Policy

Use this task to create a policy map for a Layer 3 and Layer 4 firewall policy that will be attached to zone pairs.


Note


If you are creating an inspect type policy map, note that only the following actions are allowed: drop, inspect, police, pass, service-policy, and urlfilter.

Note


You must perform at least one step from Step 5, 8, 9, or 10.
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect policy-map-name

4.    class type inspect class-name

5.    inspect [parameter-map-name]

6.    police rate bps burst size

7.    drop [log]

8.    pass

9.    service-policy type inspect policy-map-name

10.    urlfilter parameter-map-name

11.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect policy-map-name


Example:

Router(config)# policy-map type inspect p1

 

Creates a Layer 3 and Layer 4 inspect type policy map and enters QoS policy-map configuration mode.

 
Step 4
class type inspect class-name


Example:

Router(config-pmap)# class type inspect c1

 

Specifies the traffic (class) on which an action is to be performed.

 
Step 5
inspect [parameter-map-name]


Example:

Router(config-pmap-c)# inspect inspect-params

 

Enables Cisco IOS stateful packet inspection.

 
Step 6
police rate bps burst size


Example:

Router(config-pmap-c)# police rate 2000 burst 3000

 

(Optional) Limits traffic matching within a firewall (inspect) policy.

 
Step 7
drop [log]


Example:

Router(config-pmap-c)# drop

 

(Optional) Drops packets that are matched with the defined class.

Note    The actions drop and pass are exclusive, and the actions inspect and drop are exclusive; that is, you cannot specify both of them.
 
Step 8
pass


Example:

Router(config-pmap-c)# pass

 

(Optional) Allows packets that are matched with the defined class.

 
Step 9
service-policy type inspect policy-map-name


Example:

Router(config-pmap-c)# service-policy type inspect p1

 

Attaches a firewall policy map to a zone pair.

 
Step 10
urlfilter parameter-map-name


Example:

Router(config-pmap-c)# urlfilter param1

 

(Optional) Enables Cisco IOS firewall URL filtering.

 
Step 11
exit


Example:

Router(config-pmap-c)# exit

 

Returns to QoS policy-map configuration mode.

 

Configuring a Parameter Map

Depending on your policy, you can configure either an inspect, URL filter, or protocol-specific type parameter map. If you are configuring a URL filter type or protocol-specific type policy, you must configure a parameter map, as appropriate. However, a parameter map is optional if you are using an inspect type policy.


Note


Changes to the parameter map are not reflected on connections already established through the firewall. Changes are applicable only to new connections permitted to the firewall. To ensure that your firewall enforces policies strictly, clear all the connections allowed in the firewall after you change the parameter map. To clear existing connections, use the clear zone-pair inspect sessions command.

Use one of the following tasks to configure a parameter map:

Creating an Inspect Parameter Map

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type inspect {parameter-map-name | global | default}

4.    log {dropped-packets {disable | enable} | summary [flows number] [time-interval seconds]}

5.    alert {on | off}

6.    audit-trail {on | off}

7.    dns-timeout seconds

8.    icmp idle-timeout seconds

9.    max-incomplete {low | high} {number-of-connections}

10.    one-minute {low | high} number-of-connections

11.    sessions maximum sessions

12.    tcp finwait-time seconds

13.    tcp idle-time seconds

14.    tcp max-incomplete host threshold [block-time minutes]

15.    tcp synwait-time seconds

16.    tcp window-scale-enforcement loose

17.    udp idle-time seconds

18.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type inspect {parameter-map-name | global | default}


Example:

Router(config)# parameter-map type inspect eng-network-profile

 

Configures an inspect parameter map for connecting thresholds, timeouts, and other parameters pertaining to the inspect action, and enters parameter map type inspect configuration mode.

 
Step 4
log {dropped-packets {disable | enable} | summary [flows number] [time-interval seconds]}


Example:

Router(config-profile)# log summary flows 15 time-interval 30

 

(Optional) Configures packet logging during the firewall activity.

Note    This command is visible in the parameter map type inspect configuration mode only.
 
Step 5
alert {on | off}


Example:

Router(config-profile)# alert on

 

(Optional) Turns on Cisco IOS stateful packet inspection alert messages that are displayed on the console.

 
Step 6
audit-trail {on | off}


Example:

Router(config-profile)# audit-trail on

 

(Optional) Turns on audit trail messages.

 
Step 7
dns-timeout seconds


Example:

Router(config-profile)# dns-timeout 60

 

(Optional) Specifies the domain name system (DNS) idle timeout (the length of time for which a DNS lookup session will continue to be managed while there is no activity).

 
Step 8
icmp idle-timeout seconds


Example:

Router(config-profile)# icmp idle-timeout 90

 

(Optional) Configures the timeout for ICMP sessions.

 
Step 9
max-incomplete {low | high} {number-of-connections}


Example:

Router(config-profile)# max-incomplete low 800

 

(Optional) Defines the number of existing half-open sessions that will cause the Cisco IOS firewall to start and stop deleting half-open sessions.

 
Step 10
one-minute {low | high} number-of-connections


Example:

Router(config-profile)# one-minute low 300

 

(Optional) Defines the number of new unestablished sessions that will cause the system to start deleting half-open sessions and stop deleting half-open sessions.

 
Step 11
sessions maximum sessions


Example:

Router(config-profile)# sessions maximum 200

 

(Optional) Sets the maximum number of allowed sessions that can exist on a zone pair.

  • Use this command to limit the bandwidth used by the sessions.
  • sessions--Maximum number of allowed sessions. Range: 1 to 2147483647.
 
Step 12
tcp finwait-time seconds


Example:

Router(config-profile)# tcp finwait-time 5

 

(Optional) Specifies how long a TCP session will be managed after the Cisco IOS firewall detects a FIN-exchange.

 
Step 13
tcp idle-time seconds


Example:

Router(config-profile)# tcp idle-time 90

 

(Optional) Configures the timeout for TCP sessions.

 
Step 14
tcp max-incomplete host threshold [block-time minutes]


Example:

Router(config-profile)# tcp max-incomplete host 500 block-time 10

 

(Optional) Specifies threshold and blocking time values for TCP host-specific Denial-of-Service (DoS) detection and prevention.

 
Step 15
tcp synwait-time seconds


Example:

Router(config-profile)# tcp synwait-time 3

 

(Optional) Specifies how long the software will wait for a TCP session to reach the established state before dropping the session.

 
Step 16
tcp window-scale-enforcement loose


Example:

Router(config-profile)# tcp window-scale-enforcement loose

 

(Optional) Disables the window scale option check in the parameter map for a TCP packet that has an invalid window scale option under the Zone-based policy firewall.

 
Step 17
udp idle-time seconds


Example:

Router(config-profile)# udp idle-time 75

 

(Optional) Configures the idle timeout of UDP sessions that are going through the firewall.

 
Step 18
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode and enters global configuration mode.

 

Creating a URL Filter Parameter Map

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type urlfilter parameter-map-name

4.    alert {on | off}

5.    allow-mode {on | off}

6.    audit-trail {on | off}

7.    cache number

8.    exclusive-domain {deny | permit} domain-name

9.    max-request number-of-requests

10.    max-resp-pak number-of-requests

11.    server vendor {n2h2 | websense} {ip-address | hostname [port port-number]} [outside] [log] [retrans retransmission-count] [timeout seconds]

12.    source-interface interface-name

13.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type urlfilter parameter-map-name


Example:

Router(config)# parameter-map type urlfilter eng-network-profile

 

Creates or modifies a parameter map for URL filtering parameters and enters parameter map type inspect configuration mode.

Note    This command is hidden in releases later than Cisco IOS Release 12.4(20)T, but it continues to work. The parameter-map type urlfpolicy command can also be used. This command is used to create URL filtering parameters for local, trend, Websense Internet filtering, and the N2H2 Internet blocking program. We recommend the use of the URL filter policy rather than the URL filter action for Cisco IOS Release 12.4(20)T and later releases. All the use cases supported by the URL filter as an action are also supported by the URL filter policy. See the "Configuring a URL Filter Policy" section for more information.
 
Step 4
alert {on | off}


Example:

Router(config-profile)# alert on

 

(Optional) Turns on Cisco IOS stateful packet inspection alert messages that are displayed on the console.

 
Step 5
allow-mode {on | off}


Example:

Router(config-profile)# allow-mode on

 

(Optional) Turns on the default mode of the filtering algorithm.

 
Step 6
audit-trail {on | off}


Example:

Router(config-profile)# audit-trail on

 

(Optional) Turns on audit trail messages.

 
Step 7
cache number


Example:

Router(config-profile)# cache 5

 

(Optional) Controls how the URL filter handles the cache it maintains of HTTP servers.

 
Step 8
exclusive-domain {deny | permit} domain-name


Example:

Router(config-profile)# exclusive-domain permit cisco.com

 

(Optional) Adds a domain name to or from the exclusive domain list so that the Cisco IOS firewall does not have to send lookup requests to the vendor server.

 
Step 9
max-request number-of-requests


Example:

Router(config-profile)# max-request 80

 

(Optional) Specifies the maximum number of outstanding requests that can exist at a time.

 
Step 10
max-resp-pak number-of-requests


Example:

Router(config-profile)# max-resp-pak 200

 

(Optional) Specifies the maximum number of HTTP responses that the Cisco IOS firewall can keep in its packet buffer.

 
Step 11
server vendor {n2h2 | websense} {ip-address | hostname [port port-number]} [outside] [log] [retrans retransmission-count] [timeout seconds]


Example:

Router(config-profile)# server vendor n2h2 10.193.64.22 port 3128 outside retrans 9 timeout 8

 

Specifies the URL filtering server.

 
Step 12
source-interface interface-name


Example:

Router(config-profile)# source-interface ethernet0

 

(Optional) Specifies the interface whose IP address is used as the source IP address while making a TCP connection to the URL filter server (Websense or N2H2).

 
Step 13
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode and enters global configuration mode.

 

Configuring a Layer 7 Protocol-Specific Parameter Map


Note


Protocol-specific parameter maps can be created only for instant messenger applications (AOL, ICQ, MSN Messenger, Yahoo Messenger, and Windows Messenger).
Before You Begin

To enable name resolution to occur, you must also enable the ip domain name command and the ip name-server command.


SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type protocol-info parameter-map-name

4.    server {name string [snoop] | ip {ip-address | range ip-address-start ip-address-end}}

5.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type protocol-info parameter-map-name


Example:

Router(config)# parameter-map type protocol-info ymsgr

 

Defines an application-specific parameter map and enters parameter map type inspect configuration mode.

 
Step 4
server {name string [snoop] | ip {ip-address | range ip-address-start ip-address-end}}


Example:

Router(config-profile)# server name example1.example.com

 

Configures a set of DNS servers for which a given instant messenger application will be interacting.

Note    If at least one server instance is not configured, the parameter map will not have any definitions to enforce; that is, the configured instant messenger policy cannot be enforced.
Note    To configure more than one set of servers, you can issue the server command multiple times within an instant messenger's parameter map. Multiple entries are treated cumulatively.
 
Step 5
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode and enters global configuration mode.

 
Troubleshooting Tips

To display details of an IM protocol-specific parameter map, use the show parameter-map type protocol-info command.

Configuring OoO Packet Processing Support in the Zone-Based Firewall Applications


Note


When you configure a TCP-based Layer 7 policy for DPI, OoO is enabled by default. Use the parameter-map type ooo global command to configure the OoO packet support parameters or to turn off OoO processing.

Note


In Cisco IOS Release 12.4(15)T, OoO processing was enabled for zone-based firewall and for IPS shared sessions with Layer 4 match (match protocol TCP, match protocol http), and for any TCP-based Layer 7 packet ordering.
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type ooo global

4.    tcp reassembly alarm {on | off}

5.    tcp reassembly memory limit memory-limit

6.    tcp reassembly queue length queue-length

7.    tcp reassembly timeout time-limit

8.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type ooo global


Example:

Router(config)# parameter-map type ooo global

 

Configures OoO processing and enters parameter map type inspect configuration mode.

 
Step 4
tcp reassembly alarm {on | off}


Example:

Router(config-profile)# tcp reassembly alarm on

 

Specifies the alert message configuration.

 
Step 5
tcp reassembly memory limit memory-limit


Example:

Router(config-profile)# tcp reassembly memory limit 2048

 

Specifies the OoO box-wide buffer size.

 
Step 6
tcp reassembly queue length queue-length


Example:

Router(config-profile)# tcp reassembly queue length 45

 

Specifies the OoO queue length per TCP flow.

 
Step 7
tcp reassembly timeout time-limit


Example:

Router(config-profile)# tcp reassembly timeout 34

 

Specifies the OoO queue reassembly timeout value.

 
Step 8
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode and enters global configuration mode.

 

Configuring Intrazone Support in the Zone-Based Firewall Applications

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    zone-pair security zone-pair-name [source source-zone-name destination destination-zone-name]

4.    policy-map type inspect policy-map-name

5.    class type inspect protocol-name class-map-name

6.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
zone-pair security zone-pair-name [source source-zone-name destination destination-zone-name]


Example:

Router(config)# zone-pair security zonepair17 source zone8 destination zone8

 

Specifies the name of the zone pair that is attached to an interface, the source zone for information, and the destination zone for information passing through this zone pair.

Note    To configure intrazone support, the source zone and the destination zone must be the same.
 
Step 4
policy-map type inspect policy-map-name


Example:

Router(config)# policy-map type inspect my-pmap

 

Specifies a policy map name and enters QoS policy-map configuration mode.

 
Step 5
class type inspect protocol-name class-map-name


Example:

Router(config-pmap)# class type inspect aol cmap1

 

Specifies the firewall class map protocol and name.

 
Step 6
exit


Example:

Router(config-pmap)# exit

 

Exits QoS policy-map configuration mode and enters global configuration mode.

 

Configuring Layer 7 Protocol-Specific Firewall Policies

Configure Layer 7 policy maps if you are need extra provisioning for Layer 7 inspection modules. It is not necessary that you configure all of the Layer 7 policy maps specified in this section.

Use one of the following tasks to configure a Layer 7, protocol-specific firewall policy:

Layer 7 Class Map and Policy Map Restrictions

  • DPI class maps for Layer 7 can be used in inspect policy maps of the respective type. For example, class-map type inspect http can only be used only in policy-map type inspect http.
  • DPI policies require an inspect action at the parent level.
  • A Layer 7 (DPI) policy map must be nested at the second level in a Layer 3 or Layer 4 inspect policy map, whereas a Layer 3 or Layer 4 inspect policy can be attached at the first level. Therefore, a Layer 7 policy map cannot be attached directly to a zone pair.
  • If no action is specified in the hierarchical path of an inspect service policy, the packet is dropped. Traffic matching class-default in the top-level policy is dropped if there are no explicit actions configured in class-default. If the traffic does not match any class in a Layer 7 policy, the traffic is not dropped; control returns to the parent policy and subsequent actions (if any) in the parent policy are executed on the packet.
  • Layer 7 policy maps include class maps only of the same type.
  • You can specify the reset action only for TCP traffic; it resets the TCP connection.
  • In Cisco IOS Release 15.1(4)M and later releases, removing a class that has a header with a regular expression from a Layer 7 policy map causes active HTTP sessions to reset. Prior to this change, when a class was removed from a Layer 7 policy map, the router reloaded.

Configuring an HTTP Firewall Policy

To configure match criteria on the basis of an element within a parameter map, you must configure a parameter map as shown in the task "Creating an Inspect Parameter Map."

You must specify at least one match criterion; otherwise, the firewall policy will not be effective.

Configuring an HTTP Firewall Class Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class-map type inspect http [match-any | match-all] class-map-name

4.    match response body java-applet

5.    match req-resp protocol violation

6.    match req-resp body length {lt | gt} bytes

7.    match req-resp header content-type {violation | mismatch | unknown}

8.    match {request | response | req-resp} header [header-name] count gt number

9.    match {request | response | req-resp} header [header-name] length gt bytes

10.   match request {uri | arg} length gt bytes

11.    match request method {connect | copy | delete | edit | get | getattribute | getattributenames | getproperties| head | index | lock | mkdir | move | options | post | put | revadd | revlabel | revlog | revnum | save | setattribute | startrev | stoprev | trace | unedit | unlock}

12.    match request port-misuse {im | p2p | tunneling| any}

13.    match req-resp header transfer-encoding {chunked| compress| deflate| gzip| identity| all}

14.   match {request | response | req-resp} header [header-name] regex parameter-map-name

15.    match request uri regex parameter-map-name

16.    match {request | response | req-resp} body regexparameter-map-name

17.    match response status-line regex parameter-map-name

18.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class-map type inspect http [match-any | match-all] class-map-name


Example:

Router(config)# class-map type inspect http http-class

 

Creates a class map for the HTTP protocol so that you can enter match criteria and enters QoS class- map configuration mode.

 
Step 4
match response body java-applet


Example:

Router(config-cmap)# match response body java-applet

 

(Optional) Identifies Java applets in an HTTP connection.

 
Step 5
match req-resp protocol violation


Example:

Router(config-cmap)# match req-resp protocol violation

 

(Optional) Configures an HTTP class map to allow HTTP messages to pass through the firewall or to reset the TCP connection when HTTP noncompliant traffic is detected.

 
Step 6
match req-resp body length {lt | gt} bytes


Example:

Router(config-cmap)# match req-resp body length gt 35000

 

(Optional) Configures an HTTP class map to use the minimum or maximum message size, in bytes, as a match criterion for permitting or denying HTTP traffic through the firewall.

  • The number of bytes can be from 0 to 65535.
 
Step 7
match req-resp header content-type {violation | mismatch | unknown}


Example:

Router(config-cmap)# match req-resp header content-type mismatch

 

(Optional) This command configures an HTTP class map based on the content type of the HTTP traffic.

 
Step 8
match {request | response | req-resp} header [header-name] count gt number


Example:

Router(config-cmap)# match req-resp header count gt 16

 

(Optional) Configure an HTTP firewall policy to permit or deny HTTP traffic on the basis of both request and response messages whose header count does not exceed a maximum number of fields.

 
Step 9
match {request | response | req-resp} header [header-name] length gt bytes


Example:

Router(config-cmap)# match response header length gt 50000

 

(Optional) Permits or denies HTTP traffic based on the length of the HTTP request header.

  • header-name--Specific line in the header field. If a specific line is defined, only that specific field length will be used as a match criterion.
  • gt bytes--Maximum number of bytes that can be in the header of the HTTP request. Range: 0 to 65535.
 
Step 10
match request {uri | arg} length gt bytes


Example:

Router(config-cmap)# match request uri length gt 500

 

(Optional) Configures an HTTP firewall policy to use the URI or argument length in the request message as a match criterion for permitting or denying HTTP traffic.

 
Step 11
match request method {connect | copy | delete | edit | get | getattribute | getattributenames | getproperties| head | index | lock | mkdir | move | options | post | put | revadd | revlabel | revlog | revnum | save | setattribute | startrev | stoprev | trace | unedit | unlock}


Example:

Router(config-cmap)# match request method connect

 

(Optional) Configures an HTTP firewall policy to use the request methods or the extension methods as a match criterion for permitting or denying HTTP traffic.

 
Step 12
match request port-misuse {im | p2p | tunneling| any}


Example:

Router(config-cmap)# match request port-misuse any

 

(Optional) Identifies applications misusing the HTTP port.

 
Step 13
match req-resp header transfer-encoding {chunked| compress| deflate| gzip| identity| all}


Example:

Router(config-cmap)# match req-resp header transfer-encoding compress

 

(Optional) Permits or denies HTTP traffic according to the specified transfer encoding of the message.

  • chunked--Encoding format (specified in RFC 2616, Hypertext Transfer Protocol--HTTP/1 ) in which the body of the message is transferred in a series of chunks; each chunk contains its own size indicator.
  • compress--Encoding format produced by the UNIX compress utility.
  • deflate--ZLIB format defined in RFC 1950, ZLIB Compressed Data Format Specification Version 3.3 , combined with the deflate compression mechanism described in RFC 1951, DEFLATE Compressed Data Format Specification Version 1.3 .
  • gzip--Encoding format produced by the gzip (GNU zip) program.
  • identity--Default encoding, which indicates that no encoding has been performed.
  • all--All of the transfer encoding types.
 
Step 14
match {request | response | req-resp} header [header-name] regex parameter-map-name


Example:

Router(config-cmap)# match req-resp header regex non_ascii_regex

 

(Optional) Configures HTTP firewall policy match criteria on the basis of headers that match the regular expression defined in a parameter map.

  • HTTP has two regular expression (regex) options. One combines the header keyword, content-type header name, and regex keyword and parameter-map-name argument. The other combines the header keyword, regex keyword, and parameter-map-name argument.
  • If the header and regex keywords are used with the parameter-map-name argument, the parameter map does not require a period and asterisk in front of the parameter-map-name argument. For example, either "html" or ".*html" parameter-map-name argument can be configured.
  • If the header keyword is used with the content-type header name and regex keyword, then the parameter map name requires a period and asterisk (.*) in front of the parameter-map-name argument. For example, the parameter-map-name argument "html" is expressed as: .*html.
Note    If the period and asterisk are added in front of "html" (.*html), the parameter-map-name argument works for both HTTP regex options.
  • The mismatch keyword is valid only for the match response header content-type regex command syntax for messages that need to be matched and that have a content-type header name mismatch.
Tip   

It is a good practice to add ".*" to the regex parameter-map-name arguments that are not present at the beginning of a text string.

 
Step 15
match request uri regex parameter-map-name


Example:

Router(config-cmap)# match request uri regex uri_regex_cm

 

(Optional) Configures an HTTP firewall policy to permit or deny HTTP traffic on the basis of request messages whose URI or arguments (parameters) match a defined regular expression.

 
Step 16
match {request | response | req-resp} body regexparameter-map-name


Example:

Router(config-cmap)# match response body regex body_regex

 

(Optional) Configures a list of regular expressions that are to be matched against the body of the request, response, or both the request and response message.

 
Step 17
match response status-line regex parameter-map-name


Example:

Router(config-cmap)# match response status-line regex status_line_regex

 

(Optional) Specifies a list of regular expressions that are to be matched against the status line of a response message.

 
Step 18
end


Example:

Router(config-cmap)# end

 

(Optional) Exits QoS class- map configuration mode and enters privileged EXEC mode .

 
Configuring an HTTP Firewall Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect http policy-map-name

4.    class-type inspect http http-class-name

5.    allow

6.    log

7.    reset

8.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect http policy-map-name


Example:

Router(config)# policy-map type inspect http myhttp-policy

 

Creates a Layer 7 HTTP policy map and enters QoS policy-map configuration mode.

 
Step 4
class-type inspect http http-class-name


Example:

Router(config-pmap)# class-type inspect http http-class

 

Creates a class map for the HTTP protocol.

 
Step 5
allow


Example:

Router(config-pmap)# allow

 

(Optional) Allows a traffic class matching the class.

 
Step 6
log


Example:

Router(config-pmap)# log

 

Generates a log (messages).

 
Step 7
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets a TCP connection if the data length of the SMTP body exceeds the value configured in the class-map type inspect smtp command.

 
Step 8
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring a URL Filter Policy

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type urlfpolicy {local | n2h2 | websense} parameter-map-name

4.    exit

5.    class-map type urlfilter {class-map-name | match-any class-map-name | n2h2 {class-map-name | match-any class-map-name} | websense {class-map-name | match-any class-map-name}}

6.    exit

7.    policy-map type inspect urlfilter policy-map-name

8.    service-policy urlfilter policy-map-name

9.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type urlfpolicy {local | n2h2 | websense} parameter-map-name


Example:

Router(config)# parameter-map type urlfpolicy websense websense-param-map

 

Configures the URL filter name related to the parameter map, which can include local, Websense, or N2H2 parameters and enters parameter map type inspect configuration mode.

 
Step 4
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode.

 
Step 5
class-map type urlfilter {class-map-name | match-any class-map-name | n2h2 {class-map-name | match-any class-map-name} | websense {class-map-name | match-any class-map-name}}


Example:

Router(config)# class-map type urlfilter websense websense-param-map

 

Configures the class map for the URL filter and enters Qos class-map configuration mode.

 
Step 6
exit


Example:

Router(config-cmap)# exit

 

Exits QoS class-map configuration mode and enters global configuration mode.

 
Step 7
policy-map type inspect urlfilter policy-map-name


Example:

Router(config)# policy-map type inspect urlfilter websense-policy

 

Configures the URL filter policy.

 
Step 8
service-policy urlfilter policy-map-name


Example:

Router(config)# service-policy urlfilter websense-policy

 

Applies the URL filter policy under the inspect class as the service policy.

 
Step 9
exit


Example:

Router(config)# exit

 

Exits global configuration mode and enters privileged EXEC mode.

 

Configuring an IMAP Firewall Policy

Configuring an IMAP Class Map

Perform this task to configure an IMAP class map.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip inspect name inspection-name protocol [alert {on | off}] [audit-trail {on | off}] [reset] [secure-login] [timeout seconds]

4.    class-map type inspect imap [match-any] class-map-name

5.    log

6.    match invalid-command

7.    match login clear-text

8.    exit


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
ip inspect name inspection-name protocol [alert {on | off}] [audit-trail {on | off}] [reset] [secure-login] [timeout seconds]


Example:

Router(config)# ip inspect name mail-guard imap

 

Defines a set of inspection rules.

 
Step 4
class-map type inspect imap [match-any] class-map-name


Example:

Router(config)# class-map type inspect imap imap-class

 

Creates a class map for IMAP to enter the match criterion, and enters QoS class-map configuration mode.

 
Step 5
log


Example:

Router(config-cmap)# log

 

Generates a log of messages.

 
Step 6
match invalid-command


Example:

Router(config-cmap)# match invalid-command

 

(Optional) Locates invalid commands on an IMAP connection.

 
Step 7
match login clear-text


Example:

Router(config-cmap)# match login clear-text

 

(Optional) Locates nonsecure login when an IMAP server is used.

 
Step 8
exit


Example:

Router(config-cmap)# exit

 

Exits QoS class-map configuration mode and returns to global configuration mode.

 
Configuring an IMAP Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect imap policy-map-name

4.    class-type inspect imap imap-class-name

5.    log

6.    reset

7.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect imap policy-map-name


Example:

Router(config)# policy-map type inspect imap myimap-policy

 

Creates a Layer 3 IMAP policy map and enters QoS policy-map configuration mode.

 
Step 4
class-type inspect imap imap-class-name


Example:

Router(config-pmap)# class-type inspect imap pimap

 

Creates a class map for the IMAP protocol.

 
Step 5
log


Example:

Router(config-pmap)# log

 

Generates a log (messages).

 
Step 6
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets a TCP connection if the data length of the SMTP body exceeds the value that you configured in the class-map type inspect smtp command.

 
Step 7
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring an Instant Messenger Policy

Configuring an IM Class Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class map type inspect {aol | msnmsgr | ymsgr | icg | winmsgr} [match-any] class-map-name

4.    match service {any | text-chat}

5.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class map type inspect {aol | msnmsgr | ymsgr | icg | winmsgr} [match-any] class-map-name


Example:

Router(config)# class map type inspect aol myaolclassmap

 

Creates an IM type class map so you can begin adding match criteria and enters QoS class-map configuration mode.

 
Step 4
match service {any | text-chat}


Example:

Router(config-cmap)# match service text-chat

 

(Optional) Creates a match criterion on the basis of text chat messages.

 
Step 5
end


Example:

Router(config-cmap)# end

 

Exits QoS class-map configuration mode and enters privileged EXEC mode.

 
Configuring an IM Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy map type inspect protocol-name policy-map-name

4.    class type inspect {aol | msnmsgr | ymsgr | icq | winmsgr} class-map-name

5.    reset

6.    log

7.    allow

8.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy map type inspect protocol-name policy-map-name


Example:

Router(config)# policy map type inspect aol myaolpolicymap

 

Creates an IM policy map and enters QoS policy-map configuration mode.

 
Step 4
class type inspect {aol | msnmsgr | ymsgr | icq | winmsgr} class-map-name


Example:

Router(config-pmap)# class type inspect aol myaolclassmap

 

Specifies a traffic class on which an action is to be performed.

  • class-map-name--This class map name should match the class map specified by using the class-map type inspect command.
 
Step 5
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets the connection.

 
Step 6
log


Example:

Router(config-pmap)# log

 

(Optional) Generates a log message for the matched parameters.

 
Step 7
allow


Example:

Router(config-pmap)# allow

 

(Optional) Allows the connection.

 
Step 8
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring a Peer-to-Peer Policy

You can create a P2P policy for the following P2P applications: eDonkey, FastTrack, Gnutella, and Kazaa Version 2.

Configuring a P2P Class Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class map type inspect {edonkey | fasttrack | gnutella | kazaa2} [match-any] class-map-name

4.    match file-transfer [regular-expression]

5.    match search-file-name [regular-expression]

6.    match text-chat [regular-expression]

7.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class map type inspect {edonkey | fasttrack | gnutella | kazaa2} [match-any] class-map-name


Example:

Router(config)# class map type inspect edonkey myclassmap

 

Creates a P2P type class map so that you can begin adding match criteria and enters QoS class-map configuration mode.

 
Step 4
match file-transfer [regular-expression]


Example:

Router(config-cmap)# match file-transfer *

 

(Optional) Matches file transfer connections within any supported P2P protocol.

Note    To specify that all file transfer connections should be identified by the traffic class, use "*" as the regular expression.
 
Step 5
match search-file-name [regular-expression]


Example:

Router(config-cmap)# match search-file-name

 

(Optional) Blocks filenames within a search request for clients using the eDonkey P2P application.

Note    This command is applicable only for the eDonkey P2P application.
 
Step 6
match text-chat [regular-expression]


Example:

Router(config-cmap)# match text-chat

 

(Optional) Blocks text chat messages between clients using the eDonkey P2P application.

Note    This command is applicable only for the eDonkey P2P application.
 
Step 7
end


Example:

Router(config-cmap)# end

 

Exits QoS class-map configuration mode and enters privileged EXEC mode.

 
Configuring a P2P Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy map type inspect p2p policy-map-name

4.    class type inspect {edonkey | fasttrack | gnutella | kazaa2} class-map-name

5.    reset

6.    log

7.    allow

8.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy map type inspect p2p policy-map-name


Example:

Router(config)# policy map type inspect p2p mypolicymap

 

Creates a P2P policy map and enters QoS policy-map configuration mode.

 
Step 4
class type inspect {edonkey | fasttrack | gnutella | kazaa2} class-map-name


Example:

Router(config-pmap)# class type inspect edonkey myclassmap

 

Specifies a traffic class on which an action is to be performed and enters policy map configuration mode.

  • class-map-name--This class map name should match the class map specified through the class-map type inspect command.
 
Step 5
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets the connection.

 
Step 6
log


Example:

Router(config-pmap)# log

 

(Optional) Generates a log message for the matched parameters.

 
Step 7
allow


Example:

Router(config-pmap)# allow

 

(Optional) Allows the connection.

 
Step 8
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring a POP3 Firewall Policy

Configuring a POP3 Firewall Class Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip inspect name inspection-name protocol [alert {on | off}] [audit-trail {on | off}] [reset] [secure-login] [timeout seconds]

4.    class-map type inspect pop3 [match-any] class-map-name

5.    match invalid-command

6.    match login clear-text

7.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
ip inspect name inspection-name protocol [alert {on | off}] [audit-trail {on | off}] [reset] [secure-login] [timeout seconds]


Example:

Router(config)# ip inspect name mail-guard pop3

 

Defines a set of inspection rules.

 
Step 4
class-map type inspect pop3 [match-any] class-map-name


Example:

Router(config)# class-map type inspect pop3 pop3-class

 

Creates a class map for the POP3 protocol to enter match criteria and enters QoS class-map configuration mode.

 
Step 5
match invalid-command


Example:

Router(config-cmap)# match invalid-command

 

(Optional) Locates invalid commands on a POP3 server.

 
Step 6
match login clear-text


Example:

Router(config-cmap)# match login clear-text

 

(Optional) Finds a nonsecure login when using a POP3 server.

 
Step 7
end


Example:

Router(config-cmap)# end

 

Exits QoS class-map configuration mode and enters privileged EXEC mode.

 
Configuring a POP3 Firewall Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect pop3 policy-map-name

4.    class-type inspect pop3 pop3-class-name

5.    log

6.    reset

7.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect pop3 policy-map-name


Example:

Router(config)# policy-map type inspect pop3 mypop3-policy

 

Creates a Layer 7 POP3 policy map and enters QoS policy-map configuration mode.

 
Step 4
class-type inspect pop3 pop3-class-name


Example:

Router(config-pmap)# class-type inspect pop3 pcl

 

Creates a class map for the POP3 protocol.

 
Step 5
log


Example:

Router(config-pmap)# log

 

Generates a log (messages).

 
Step 6
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets a TCP connection if the data length of the SMTP body exceeds the value that you configured in the class-map type inspect smtp command.

 
Step 7
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring an SMTP Firewall Policy

Configuring an SMTP Firewall Class Map

Note


To enable inspection for extended SMTP (ESMTP) in a class map, use the match protocol smtp extended command. See the "Restrictions for Zone-Based Policy Firewall" section for more information on using this command in Cisco IOS Release 12.4(15)T.
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class-map type inspect smtp [match-all | match-any] class-map-name

4.    match data-length gt max-data-value

5.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class-map type inspect smtp [match-all | match-any] class-map-name


Example:

Router(config)# class-map type inspect smtp smtp-class

 

Creates a class map for the SMTP protocol to enter match criteria and enters QoS class- map configuration mode.

 
Step 4
match data-length gt max-data-value


Example:

Router(config-cmap)# match data-length gt 200000

 

Determines if the amount of data transferred in an SMTP connection is above the configured limit.

 
Step 5
end


Example:

Router(config-cmap)# end

 

Exits QoS class-map configuration mode and enters privileged EXEC mode.

 
Configuring an SMTP Firewall Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect smtp policy-map-name

4.    class-type inspect smtp smtp-class-name

5.    reset

6.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect smtp policy-map-name


Example:

Router(config)# policy-map type inspect smtp mysymtp-policy

 

Creates a Layer 7 SMTP policy map and enters QoS policy-map configuration mode.

 
Step 4
class-type inspect smtp smtp-class-name


Example:

Router(config-pmap)# class-type inspect smtp sc

 

Configures inspection parameters for the SMTP protocol.

 
Step 5
reset


Example:

Router(config-pmap)# reset

 

(Optional) Resets the TCP connection if the data length of the SMTP body exceeds the value that you configured in the class-map type inspect smtp command.

 
Step 6
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring a SUNRPC Firewall Policy


Note


If you are inspecting an RPC protocol (that is, you have specified the match protocol sunrpc command in the Layer 4 class map), the Layer 7 SUNRPC policy map is required.
Configuring a SUNRPC Firewall Class Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    class-map type inspect sunrpc [match-any] class-map-name

4.    match program-number program-number

5.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
class-map type inspect sunrpc [match-any] class-map-name


Example:

Router(config)# class-map type inspect sunrpc long-urls

 

Creates a class map for the SUNRPC protocol to enter match criteria and enters QoS class-map configuration mode.

 
Step 4
match program-number program-number


Example:

Router(config-cmap)# match program-number 2345

 

(Optional) Specifies the allowed Remote Procedure Call (RPC) protocol program number as a match criterion.

 
Step 5
end


Example:

Router(config-cmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 
Configuring a SUNRPC Firewall Policy Map
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    policy-map type inspect sunrpc policy-map-name

4.    class-type inspect sunrpc sunrpc-class-name

5.    allow [wait-time minutes]

6.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
policy-map type inspect sunrpc policy-map-name


Example:

Router(config)# policy-map type inspect sunrpc my-rpc-policy

 

Creates a Layer 7 SUNRPC policy map and enters policy-map configuration mode.

 
Step 4
class-type inspect sunrpc sunrpc-class-name


Example:

Router(config-pmap)# class-type inspect sunrpc cs1

 

Configures inspection parameters for the SUNRPC protocol.

 
Step 5
allow [wait-time minutes]


Example:

Router(config-pmap)# allow wait-time 10

 

(Optional) Allows the configured program number.

  • Specifies the number of minutes to keep a small hole in the firewall to allow subsequent connections from the same source address and to the same destination address and port. The default wait time is zero minutes. This keyword is available only for the RPC protocol.
 
Step 6
end


Example:

Router(config-pmap)# end

 

Exits QoS policy-map configuration mode and enters privileged EXEC mode.

 

Configuring an MSRPC Firewall Policy


Note


If you are inspecting an RPC protocol (that is, you have specified the match protocol msrpc command in the Layer 4 class map), the Layer 7 Microsoft Remote Procedure Call (MSRPC) policy map is required.

Perform this task to configure an MSRPC firewall policy.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    parameter-map type protocol-info msrpc parameter-map-name

4.    timeout seconds

5.    exit

6.    class-map type inspect match-any class-map-name

7.    match protocol msrpc

8.    match protocol msrpc-smb-netbios

9.    exit

10.    policy-map type inspect policy-map-name

11.    class type inspect class-map-name

12.    inspect

13.    exit

14.    class class-default

15.    drop

16.    exit

17.    exit

18.    zone security security-zone-name

19.    exit

20.    zone security security-zone-name

21.    exit

22.    zone-pair security zone-pair-name source source-zone destination destination-zone

23.    service-policy type inspect policy-map-name

24.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
parameter-map type protocol-info msrpc parameter-map-name


Example:

Router(config)# parameter-map type protocol-info msrpc para-map

 

Defines an application-specific parameter map and enters parameter map type inspect configuration mode.

 
Step 4
timeout seconds


Example:

Router(config-profile)# timeout 60

 

Configures the MSRPC endpoint mapper (EPM) timeout.

 
Step 5
exit


Example:

Router(config-profile)# exit

 

Exits parameter map type inspect configuration mode and enters global configuration mode.

 
Step 6
class-map type inspect match-any class-map-name


Example:

Router(config)# class-map type inspect match-any c-map

 

Creates an inspect type class map for the traffic class and enters QoS class-map configuration mode.

 
Step 7
match protocol msrpc


Example:

Router(config-cmap)# match protocol msrpc

 

Configures match criteria for a class map on the basis of a specified protocol.

  • Only Cisco IOS stateful packet inspection-supported protocols can be used as match criteria in inspect type class maps.
 
Step 8
match protocol msrpc-smb-netbios


Example:

Router(config-cmap)# match protocol msrpc-smb-netbios

 

Configures match criteria for a class map on the basis of a specified protocol.

  • Only Cisco IOS stateful packet inspection-supported protocols can be used as match criteria in inspect type class maps.
 
Step 9
exit


Example:

Router(config-cmap)# exit

 

Exits QoS class-map configuration mode and enters global configuration mode.

 
Step 10
policy-map type inspect policy-map-name


Example:

Router(config)# policy-map type inspect p-map

 

Creates a Layer 3 and Layer 4 inspect type policy map and enters QoS policy-map configuration mode.

 
Step 11
class type inspect class-map-name


Example:

Router(config-pmap)# class type inspect c-map

 

Specifies the traffic (class) on which an action is to be performed and enters QoS policy-map class configuration mode.

 
Step 12
inspect


Example:

Router(config-pmap-c)# inspect

 

Enables Cisco IOS stateful packet inspection.

 
Step 13
exit


Example:

Router(config-pmap-c)# exit

 

Exits QoS policy-map class configuration mode and enters QoS policy-map configuration mode.

 
Step 14
class class-default


Example:

Router(config-pmap)# class class-default

 

Specifies the matching of the system default class and enters QoS policy-map class configuration mode.

  • If the system default class is not specified, then unclassified packets are matched.
 
Step 15
drop


Example:

Router(config-pmap-c)# drop

 

Drops packets that matches a defined class.

 
Step 16
exit


Example:

Router(config-pmap-c)# exit

 

Exits QoS policy-map class configuration mode and enters QoS policy-map configuration mode.

 
Step 17
exit


Example:

Router(config-pmap)# exit

 

Exits QoS policy-map configuration mode and enters global configuration mode.

 
Step 18
zone security security-zone-name


Example:

Router(config)# zone security in-zone

 

Creates a security zone to which interfaces can be assigned and enters security zone configuration mode.

 
Step 19
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 20
zone security security-zone-name


Example:

Router(config)# zone security out-zone

 

Creates a security zone to which interfaces can be assigned and enters security zone configuration mode.

 
Step 21
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 22
zone-pair security zone-pair-name source source-zone destination destination-zone


Example:

Router(config)# zone-pair security in-out source in-zone destination out-zone

 

Creates a zone pair and enters security zone configuration mode.

Note    To apply a policy, you must configure a zone pair.
 
Step 23
service-policy type inspect policy-map-name


Example:

Router(config-sec-zone)# service-policy type inspect p-map

 

Attaches a firewall policy map to the destination zone pair.

Note    If a policy is not configured between a pair of zones, traffic is dropped by default.

 
Step 24
end


Example:

Router(config-sec-zone)# end

 

Exits security zone configuration mode and enters privileged EXEC mode.

 

Creating Security Zones and Zone Pairs and Attaching a Policy Map to a Zone Pair

You need two security zones to create a zone pair. However, you can create only one security zone and use a system-defined security zone called "self." Note that if you select a self zone, you cannot configure inspect policing.

Use this process to complete the following tasks:

  • Create at least one security zone.
  • Define zone pairs.
  • Assign interfaces to security zones.
  • Attach a policy map to a zone pair.

Tip


Before you create zones, think about what should constitute the zones. The general guideline is that you should group interfaces that are similar when they are viewed from a security perspective.



Note


  • An interface cannot be part of a zone and a legacy inspect policy at the same time.
  • An interface can be a member of only one security zone.
  • When an interface is a member of a security zone, all traffic to and from that interface is blocked unless you configure an explicit interzone policy on a zone pair involving that zone.
  • Traffic cannot flow between an interface that is a member of a security zone and an interface that is not a member of a security zone because a policy can be applied only between two zones.
  • For traffic to flow among all the interfaces in a router, all interfaces must be members of one security zone or another. This is particularly important because after you make an interface a member of a security zone, a policy action (such as inspect or pass) must explicitly allow packets. Otherwise, packets are dropped.
  • If an interface on a router cannot be part of a security zone or firewall policy, you may have to add that interface in a security zone and configure a "pass all" policy (that is, a "dummy" policy) between that zone and other zones to which a traffic flow is desired.
  • You cannot apply an ACL between security zones or on a zone pair.
  • An ACL cannot be applied between security zones and zone pairs. Include the ACL configuration in a class map, and use policy maps to drop traffic.
  • An ACL on an interface that is a zone member should not be restrictive (strict).
  • All interfaces in a security zone must belong to the same VRF instance.
  • You can configure policies between security zones whose member interfaces are in separate VRFs. However, traffic may not flow between these VRFs if the configuration does not allow it.
  • If traffic does not flow between VRFs (because route-leaking between VRFs is not configured), the policy across VRFs is not executed. This is a configuration mistake on the routing side, not on the policy side.
  • Traffic between interfaces in the same security zone is not subject to any policy; the traffic passes freely.
  • The source and the destination zones in a zone pair must be of the type security.
  • The same zone cannot be defined as both the source and the destination.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    zone security zone-name

4.    description line-of-description

5.    exit

6.    zone-pair security zone-pair name [source source-zone-name | self] destination [self | destination-zone-name]

7.    description line-of-description

8.    exit

9.    interface type number

10.    zone-member security zone-name

11.    exit

12.    zone-pair security zone-pair-name {source source-zone-name | self]} destination [self | destination-zone-name]

13.    service-policy type inspect policy-map-name

14.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
zone security zone-name


Example:

Router(config)# zone security zone1

 

Creates a security zone to which interfaces can be assigned and enters security zone configuration mode.

 
Step 4
description line-of-description


Example:

Router(config-sec-zone)# description Internet Traffic

 

(Optional) Describes the zone.

 
Step 5
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 6
zone-pair security zone-pair name [source source-zone-name | self] destination [self | destination-zone-name]


Example:

Router(config)# zone-pair security zp source z1 destination z2

 

Creates a zone pair and enters security zone configuration mode.

Note    To apply a policy, you must configure a zone pair.
 
Step 7
description line-of-description


Example:

Router(config-sec-zone)# description accounting network

 

(Optional) Describes the zone pair.

 
Step 8
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 9
interface type number


Example:

Router(config)# interface ethernet 0

 

Configures an interface and enters interface configuration mode.

 
Step 10
zone-member security zone-name


Example:

Router(config-if)# zone-member security zone1

 

Assigns an interface to a specified security zone.

Note    When you make an interface a member of a security zone, all traffic in and out of that interface (except traffic bound for the router or initiated by the router) is dropped by default. To let traffic through the interface, you must make the zone part of a zone pair to which you should apply a policy. If the policy permits traffic, traffic can flow through that interface.
 
Step 11
exit


Example:

Router(config-if)# exit

 

Exits interface configuration mode and enters global configuration mode.

 
Step 12
zone-pair security zone-pair-name {source source-zone-name | self]} destination [self | destination-zone-name]


Example:

Router(config)# zone-pair security zp source z1 destination z2

 

Creates a zone pair and enters security zone pair configuration mode.

 
Step 13
service-policy type inspect policy-map-name


Example:

Router(config-sec-zone-pair)# service-policy type inspect p2

 

Attaches a firewall policy map to the destination zone pair.

Note    If a policy is not configured between a pair of zones, traffic is dropped by default.
 
Step 14
end


Example:

Router(config-sec-zone-pair)# end

 

Exits security zone pair configuration mode and enters privileged EXEC mode.

 

Configuring the Cisco IOS Firewall with WAAS

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip wccp service-id

4.    ip inspect waas enable

5.    class-map type inspect class-name

6.    match protocol protocol-name [signature]

7.    exit

8.    policy-map type inspect policy-map-name

9.    class class-default

10.    class-map type inspect class-name

11.    inspect

12.    exit

13.    exit

14.    zone security zone-name

15.    description line-of-description

16.    exit

17.    zone-pair security zone-pair name [source source-zone-name | self] destination [self | destination-zone-name]

18.    description line-of-description

19.    exit

20.    interface type number

21.    description line-of-description

22.    zone-member security zone-name

23.    ip address ip-address

24.    ip wccp {service-id {group-listen | redirect {in | out}} | redirect exclude in | web-cache {group-listen | redirect {in | out}}

25.    exit

26.    zone-pair security zone-pair-name {source source-zone-name | self]} destination [self | destination-zone-name]

27.    service-policy type inspect policy-map-name

28.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
ip wccp service-id


Example:

Router(config)# ip wccp 61

 

Enters the WCCP dynamically defined service identifier number.

 
Step 4
ip inspect waas enable


Example:

Router(config)# ip inspect waas enable

 

Enables the Cisco IOS firewall inspection so that WAAS optimization can be discovered.

Note    If an ISR router along with Cisco IOS Firewall is deployed as an intermediary router inside the WAAS optimization path, the ip inspect waas enable command should be used to enable WAAS awareness and interoperability. If the router is not configured for optimization awareness, the optimized traffic would violate the TCP activity expectations, and the firewall would drop the traffic.
 
Step 5
class-map type inspect class-name


Example:

Router(config)# class-map type inspect most-traffic

 

Creates an inspect type class map for the traffic class and enters QoS class-map configuration mode.

Note    The class-map type inspect most-trafficcommand is hidden.
 
Step 6
match protocol protocol-name [signature]


Example:

Router(config-cmap)# match protocol http

 

Configures match criteria for a class map on the basis of a specified protocol and enters security zone configuration mode.

  • Only Cisco IOS stateful packet inspection-supported protocols can be used as match criteria in inspect type class maps.
  • signature--Signature-based classification for peer-to-peer (P2P) packets is enabled.
 
Step 7
exit


Example:

Router(config-sec-zone)# exit

 

Returns to global configuration mode.

 
Step 8
policy-map type inspect policy-map-name


Example:

Router(config)# policy-map type inspect p1

 

Creates a Layer 3 and Layer 4 inspect type policy map and enters QoS policy-map configuration mode.

 
Step 9
class class-default


Example:

Router(config-pmap)# class class-default

 

Specifies the matching of the system default class.

  • If the system default class is not specified, unclassified packets are matched.
 
Step 10
class-map type inspect class-name


Example:

Router(config-pmap)# class-map type inspect most-traffic

 

Specifies the firewall traffic (class) map on which an action is to be performed and enters QoS policy-map class configuration mode.

 
Step 11
inspect


Example:

Router(config-pmap-c)# inspect

 

Enables Cisco IOS stateful packet inspection.

 
Step 12
exit


Example:

Router(config-pmap-c)# exit

 

Exits QoS policy-map class configuration mode and enters policy map configuration mode.

 
Step 13
exit


Example:

Router(config-pmap)# exit

 

Exits policy map configuration mode and enters global configuration mode.

 
Step 14
zone security zone-name


Example:

Router(config)# zone security zone1

 

Creates a security zone to which interfaces can be assigned and enters security zone configuration mode.

 
Step 15
description line-of-description


Example:

Router(config-sec-zone)# description Internet Traffic

 

(Optional) Describes the zone.

 
Step 16
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 17
zone-pair security zone-pair name [source source-zone-name | self] destination [self | destination-zone-name]


Example:

Router(config)# zone-pair security zp source z1 destination z2

 

Creates a zone pair and enters security zone configuration mode.

Note    To apply a policy, you must configure a zone pair.
 
Step 18
description line-of-description


Example:

Router(config-sec-zone)# description accounting network

 

(Optional) Describes the zone pair.

 
Step 19
exit


Example:

Router(config-sec-zone)# exit

 

Exits security zone configuration mode and enters global configuration mode.

 
Step 20
interface type number


Example:

Router(config)# interface ethernet 0

 

Specifies an interface and enters interface configuration mode.

 
Step 21
description line-of-description


Example:

Router(config-if)# description zone interface

 

(Optional) Describes the interface.

 
Step 22
zone-member security zone-name


Example:

Router(config-if)# zone-member security zone1

 

Assigns an interface to a specified security zone.

Note    When you make an interface a member of a security zone, all traffic in and out of that interface (except the traffic bound for the router or initiated by the router) is dropped by default. To let traffic through the interface, you must make the zone part of a zone pair to which you apply a policy. If the policy permits traffic, traffic can flow through that interface.
 
Step 23
ip address ip-address


Example:

Router(config-if)# ip address 10.70.0.1 255.255.255.0

 

Assigns the interface IP address for the security zone.

 
Step 24
ip wccp {service-id {group-listen | redirect {in | out}} | redirect exclude in | web-cache {group-listen | redirect {in | out}}


Example:

Router(config-if)# ip wccp 61 redirect in

 

Specifies the following WCCP parameters on the interface:

  • The service-id argument defines a service identifier number from 1 to 254.
  • The redirect exclude in keywords are used to exclude inbound packets from outbound redirection.
  • The web-cache keyword is used to define the standard web caching service.
  • The group-listen keyword is used for discovering multicast WCCP protocol packets.
  • The in keyword is used to redirect to a cache engine the appropriate inbound packets.
  • The out keyword is used to redirect to a cache engine the appropriate outbound packets.
 
Step 25
exit


Example:

Router(config-if)# exit

 

Exits interface configuration mode and enters global configuration mode.

 
Step 26
zone-pair security zone-pair-name {source source-zone-name | self]} destination [self | destination-zone-name]


Example:

Router(config)# zone-pair security zp source z1 destination z2

 

Creates a zone pair and enters security zone pair configuration mode.

 
Step 27
service-policy type inspect policy-map-name


Example:

Router(config-sec-zone-pair)# service-policy type inspect p2

 

Attaches a firewall policy map to the destination zone pair.

Note    If a policy is not configured between a pair of zones, traffic is dropped by default.
 
Step 28
end


Example:

Router(config-sec-zone-pair)# end

 

Exits security zone pair configuration mode and enters privileged EXEC mode.

 

Configuration Examples for Zone-Based Policy Firewall

Example: Configuring Layer 3 and Layer 4 Firewall Policies

The following example shows a Layer 3 or Layer 4 top-level policy. The traffic is matched to the ACL,199 and deep-packet HTTP inspection is configured. Configuring the match access-group 101 enables Layer 4 inspection. As a result, Layer 7 inspection is omitted unless the class-map is of type mach-all.

class-map type inspect match-all http-traffic 
 match protocol http
 match access-group 101
policy-map type inspect mypolicy
 class type inspect http-traffic
  inspect
  service-policy http http-policy 

Example: Configuring Layer 7 Protocol-Specific Firewall Policies

The following example shows how to match HTTP sessions that have a URL length greater than 500. The Layer 7 policy action reset is configured.

class-map type inspect http long-urls
 match request uri length gt 500
policy-map type inspect http http-policy
 class type inspect http long-urls
  reset

The following example shows how to enable inspection for ESMTP by including the extended keyword:

class-map type inspect c1
 match protocol smtp extended
policy-map type inspect p1
 class type inspect c1
  inspect

The service-policy type inspect smtp command is optional and can be entered after the inspect command.

Example Configuring an URL Filter Policy

parameter-map type urlfpolicy websense-param-map
class-map type urlfilter websense websense-param-map
policy-map type inspect urlfilter websense-policy
service-policy urlfilter websense-policy

Example: Configuring a URL Filter Policy Websense

The following example shows how to configure a URL filter policy for Websense:

Example Websense Server Configuration

The following example shows how to configure the Websense server:

parameter-map type urlfpolicy websense websense-param-map
 server fw21-ss1-bldr.example.com timeout 30
 source-interface Loopback0
 truncate script-parameters
 cache-size maximum-entries 100
 cache-entry-lifetime 1
 block-page redirect-url http://abc.example.com
Example Configuring the Websense Class Map

The following example shows how to configure the Websense class map:

class-map type urlfilter websense match-any websense-class
 match server-response any
Example Configuring the Websense URL Filter Policy

The following example shows how to configure the Websense URL filter policy:

policy-map type inspect urlfilter websense-policy
 parameter type urlfpolicy websense websense-param-map
 class type urlfilter websense websense-class
  server-specified-action
  log

Example: Creating Security Zones and Zone Pairs and Attaching a Policy Map to a Zone Pair

Example: Creating a Security Zone

The following example shows how to create security zone z1, which is called Internet Traffic:

zone security z1 
 description Internet Traffic 

Example: Creating Zone Pairs

A zone-based firewall drops a packet if it is not explicitly allowed by a rule or policy in contrast to a legacy firewall, which permits a packet if it is not explicitly denied by a rule or policy by default.

A zone-based firewall behaves differently in handling intermittent ICMP responses generated within a zone as a result of the traffic flowing between in-zones and out-zones.

In a configuration where an explicit policy is configured for the self zone to go out of its zone and for the traffic moving between the in-zone and out-zone, if any intermittent ICMP responses are generated, then the zone-based firewall looks for a explicit permit rule for the ICMP protocol in the self zone to go out of its zone. An explicit inspect rule for the ICMP protocol for the self zone to go out-zone may not help because there is not a session associated with the intermittent ICMP responses.

The following example shows how to create zones z1 and z2, describes the zones, and specifies that the firewall policy map is applied in zone z2 for traffic flowing between the zones:

zone security z1
 description finance department networks
zone security z2
 description engineering services network
zone-pair security zp source z1 destination z2

Example: Assigning an Interface to a Security Zone

The following example shows how to attach Ethernet interface 0 to zone z1:

interface ethernet0
 zone-member security z1

Example Attaching a Policy Map to a Zone Pair

The following example shows how to attach a firewall policy map to the target zone pair p1:

zone-pair security zp source z1 destination z2 
 service-policy type inspect p1 

Example: Cisco IOS Firewall Configuration with WAAS

The following is a sample of an end-to-end WAAS traffic flow optimization configuration for the Cisco IOS firewall that uses WCCP to redirect traffic to a WAE device for traffic interception.

The following configuration example prevents traffic from being dropped between security zone members because the integrated-service-engine interface is configured on a different zone and each security zone member is assigned an interface. This change was made to the Cisco IOS firewall configuration in Cisco IOS Release 12.4(20)T and 12.4(22)T to address the different input interfaces.

ip wccp 61 
ip wccp 62 
ip inspect waas enable 
class-map type inspect most-traffic 
match protocol icmp 
match protocol ftp 
match protocol tcp 
match protocol udp 
policy--map type inspect p1 
class type inspect most--traffic 
inspect 
class class--default 
zone security zone-hr 
zone security zone-outside 
zone security z-waas
zone--pair security hr--out source zone-hr destination zone-outside 
service--policy type inspect p1 
zone--pair security out--hr source zone-outside destination zone-hr 
service--policy type inspect p1 
zone--pair security eng--out source zone-eng destination zone-outside 
service--policy type inspect p1
interface GigabitEthernet0/0 
description Trusted interface 
ipaddress 10.70.0.1 255.255.255.0 
ip wccp 61 redirect in 
zone--member security zone-hr 
interface GigabitEthernet0/0 
description Trusted interface 
ipaddress 10.71.0.2 255.255.255.0 
ip wccp 61 redirect in 
zone--member security zone-eng 
interface GigabitEthernet0/1 
description Untrusted interface 
ipaddress 10.72.2.3 255.255.255.0 
ip wccp 62 redirect in 
zone--member security zone-outside 

Note


The new configuration in Cisco IOS Release 12.4(20)T and 12.4(22)T places the integrated service engine in its own zone and need not be part of any zone pair. The zone pairs are configured between zone-hr (zone-out) and zone-eng (zone-output).
interface Integrated--Service--Enginel/0 
ipaddress 10.70.100.1 255.255.255.252 
ip wccp redirect exclude in 
zone--member security z-waas 

Example: Protocol Match Data Not Incrementing for a Class Map

The following configuration example causes the match counter problem in the show policy-map type inspect zone-pair command output:

class-map type inspect match-any y
 match protocol tcp
 match protocol icmp
class-map type inspect match-all x
 match class y

However, cumulative counters for the configuration is displayed in the show policy-map type inspect zone-pair command output if the class map matches any class map:

show policy-map type inspect zone session
policy exists on zp zp
 Zone-pair: zp
  Service-policy inspect : fw
    Class-map: x (match-any)
      Match: class-map match-any y
        2 packets, 48 bytes   <======= Cumulative class map counters are incrementing.
        30 second rate 0 bps
        Match: protocol tcp
          0 packets, 0 bytes     <==== The match for the protocol is not incrementing.
          30 second rate 0 bps
        Match: protocol icmp
          0 packets, 0 bytes
          30 second rate 0 bps
   Inspect
      Number of Established Sessions = 1
      Established Sessions
        Session 53105C0 (10.1.1.2:19180)=>(172.1.1.2:23) telnet:tcp SIS_OPEN
          Created 00:00:02, Last heard 00:00:02
          Bytes sent (initiator:responder) [30:69]
    Class-map: class-default (match-any)
      Match: any 
      Drop
        0 packets, 0 bytes

Additional References

MIBs

MIB

MIBs Link

None

To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html

Feature Information for Zone-Based Policy Firewall

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Table 1 Feature Information for Zone-Based Policy Firewall

Feature Name

Releases

Feature Information

Application Inspection and Control for HTTP--Phase 2

12.4(9)T

The Application Inspection and Control for HTTP--Phase 2 feature extends support for HTTP application firewall policies.

The following commands were introduced or modified by this feature: regexmatch body regex, match header count, match header length, match header regex, match request length, match request , match response status-line regex.

E-mail Inspection Engine

15.1(1)S

The E-mail Inspection Engine feature allows the users to inspect POP3, IMAP, and E/SMTP e-mail traffic contained in SSL VPN tunneled connections that traverse the Cisco IOS router.

P2P Application Inspection and Control--Phase 1

12.4(9)T

12.4(20)T

The P2P Application Inspection and Control--Phase 1 feature introduces support for identifying and enforcing a configured policy for the following peer-to-peer applications: eDonkey, FastTrack, Gnutella Version 2, and Kazaa Version 2.

Support for identifying and enforcing a configured policy for the following Instant Messenger applications is also introduced: AOL, MSN Messenger and Yahoo Messenger.

In Release 12.4(20)T, support was added for the following applications: H.323 VoIP and SIP.

In Release 12.4(20)T, support for the following IM applications was also added: ICQ and Windows Messenger.

The following commands were introduced or modified by this feature: class-map type inspect, class type inspect, clear parameter-map type protocol-info, debug policy-firewall, match file-transfer, match protocol (zone), match search-file-name, match service, match text-chat, parameter-map type, policy-map type inspect, server (parameter-map), show parameter-map type protocol-info.

Rate-Limiting Inspected Traffic

12.4(9)T

The Rate-Limiting Inspected Traffic feature allows users to rate limit traffic within a Cisco IOS firewall (inspect) policy. Also, users can limit the absolute number of sessions that can exist on a zone pair.

The following commands were introduced by this feature: police (zone policy), sessions maximum.

Zone-Based Policy Firewall

12.4(6)T

The Zone-Based Policy Firewall feature provides a Cisco IOS unidirectional firewall policy between groups of interfaces known as zones.

The following commands were introduced or modified by this feature:

class-map type inspect , class type inspect, clear parameter-map type protocol-info, debug policy-firewall, match body regex, match file-transfer, match header count, match header length, match header regex, match protocol (zone), match request length, match request regex, match response status-line regex, match search-file-name, match service, match text-chat, parameter-map type, policy-map type inspect, server (parameter-map), service-policy (policy-map), service-policy type inspect, show parameter-map type protocol-info.

Zone-Based Firewall Support for MSRPC

15.1(4)M

The Zone-Based Firewall Support for MSRPC feature introduces zone-based policy firewall support for Microsoft Remote Procedure Calls.

The following section provides information about this feature:

Zone-Based Firewall (ZBFW) Usability and Manageability

15.0(1)M

15.1(1)T

The Zone-Based Firewall Usability and Manageability features covered in this document are OoO packet processing support in zone-based firewalls, intrazone support in zone-based firewalls and enhanced debug capabilities.

The following commands were introduced or modified by this feature: clear ip ips statistics, debug cce dp named-db inspect, debug policy-firewall, debug ip virtual-reassembly list, parameter-map type ooo global, show parameter-map type ooo global, zone-pair security.

In Cisco IOS Release 15.1(1)T, the following commands were introduced or modified: class-map type inspect, clear policy-firewall, log (parameter-map type), match request regex, parameter-map type inspect, show parameter-map type inspect, show policy-firewall config, show policy-firewall mib, show policy-firewall sessions, show policy-firewall stats, show policy-firewall summary-log.

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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

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