Nmap: Network Exploration and Security Auditing Cookbook - Second Edition

HTTP pipelining

Some web servers' configurations support the encapsulation of more than one HTTP request in a single packet. This may speed up the execution of an NSE HTTP script, and it is recommended that you use it if the web server supports it. The http library, by default, tries to pipeline 40 requests and automatically adjusts that number according to the network conditions and the Keep-Alive header.

Users will need to set the script argument http.pipeline to adjust this value:

$ nmap -p80 --script http-methods --script-args http.pipeline=25 <target>

To implement HTTP pipelining in your NSE scripts, use the http.pipeline_add() and http.pipeline() functions. First, initiate a variable that will hold the requests:

 local reqs = nil ...