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Cisco ASA Series Firewall CLI Configuration Guide
Chapter10 Configuring Inspection of Basic Internet Protocols
HTTP Inspection
Where the regex regex_na me argument is the regular expression you created in Step1. The class
regex_class_name is the regular expression class map you created in Step2. The length gt
max_bytes is the maximum message body length in bytes.
j. (Optional) To match text found in the HTTP response message header, or to restrict the count or
length of the header, enter the following command:
ciscoasa(config-cmap)# match [not] response header {[field]
[regex [regex_name |class regex_class_name]]|
[length gt max_length_bytes |count gt max_count]}
Where the field is the predefined message header keyword. The regex regex_ name argument is the
regular expression you created in Step1. The class regex_class_name is the regular expression class
map you created in Step 2. The length gt max_bytes is the maximum message body length in bytes.
The count gt max_count is the maximum number of header fields.
k. (Optional) To match text found in the HTTP response message status line, enter the following
command:
ciscoasa(config-cmap)# match [not] response status-line {regex [regex_name | class
regex_class_name]}
Where the regex regex_na me argument is the regular expression you created in Step1. The class
regex_class_name is the regular expression class map you created in Step2.
Step4 Create an HTTP inspection policy map, enter the following command:
ciscoasa(config)# policy-map type inspect http policy_map_name
ciscoasa(config-pmap)#
Where the policy_map_name is the name of the policy map. The CLI enters policy-map configuration
mode.
Step5 (Optional) To add a description to the policy map, enter the following command:
ciscoasa(config-pmap)# description string
Step6 To apply actions to matching traffic, perform the following steps.
a. Specify the traffic on which you want to perform actions using one of the following methods:
•Specify the HTTP class map that you created in Step3 by entering the following command:
ciscoasa(config-pmap)# class class_map_name
ciscoasa(config-pmap-c)#
•Specify traffic directly in the policy map using one of the match commands described in Step3.
If you use a match not command, then any traffic that does not match the criterion in the match
not command has the action applied.
b. Specify the action you want to perform on the matching traffic by entering the following command:
ciscoasa(config-pmap-c)# {[drop [send-protocol-error] |
drop-connection [send-protocol-error]| mask | reset] [log] | rate-limit message_rate}
Not all options are available for each match or class command. See the CLI help or the command
reference for the exact options available.
The drop keyword drops all packets that match.
The send-protocol-error keyword sends a protocol error message.
The drop-connection keyword drops the packet and closes the connection.
The mask keyword masks out the matching portion of the packet.