43-16
Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter43 Configuring Inspection of Basic Internet Protocols
HTTP Inspection
hostname(config-pmap)# class ftp-traffic
hostname(config-pmap-c)# inspect ftp strict mymap
hostname(config)# service-policy ftp-policy interface inside

Verifying and Monitoring FTP Inspection

FTP application inspection generates the following log messages:
An Audit record 303002 is generated for each file that is retrieved or uploaded.
The FTP command is checked to see if it is RETR or STOR and the retrieve and store commands
are logged.
The username is obtained by looking up a table providing the IP address.
The username, source IP address, destination IP address, NAT address, and the file operation are
logged.
Audit record 201005 is generated if the secondary dynamic channel preparation failed due to
memory shortage.
In conjunction with NAT, the FTP application inspection translates the IP address within the application
payload. This is described in detail in RFC 959.
HTTP Inspection
This section describes the HTTP inspection engine. This section includes the following topics:
HTTP Inspection Overview, page43-16
Configuring an HTTP Inspection Policy Map for Additional Inspection Control, page43-17

HTTP Inspection Overview

Use the HTTP inspection engine to protect against specific attacks and other threats that are associated
with HTTP traffic. HTTP inspection performs several functions:
Enhanced HTTP inspection
URL screening through N2H2 or Websense
See Information About URL Filtering, page 39-6 for information.
Java and ActiveX filtering
The latter two features are configured in conjunction with the filter command. For more information
about filtering, see Chapter39, “Configuring Filtering Services.”
The enhanced HTTP inspection feature, which is also known as an application firewall and is available
when you configure an HTTP map (see “Configuring an HTTP Inspection Policy Map for Additional
Inspection Control”), can help prevent attackers from using HTTP messages for circumventing network
security policy. It verifies the following for all HTTP messages:
Conformance to RFC 2616
Use of RFC-defined methods only.
Compliance with the additional criteria.