Disabling HTTP Processing For Unrecognized HTTP Methods

Problem this snippet solves:

The iRule below disables HTTP processing for requests using HTTP methods that are not recognized by the BIG-IP HTTP profile. For example, Web-based Distributed Authoring and Versioning (WebDAV) uses the following extended HTTP methods: PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, LOCK, UNLOCK. Requests using one of these methods may provoke the behavior described in AskF5 SOL7581: https://support.f5.com/kb/en-us/solutions/public/7000/500/sol7581.html?sr=2105288 Unrecognized HTTP methods without a specified content-length or chunking header can cause the connection to stall . Use of these or other methods not described in RFC2616 (HTTP/1.1) may require an iRule similar to the following associated with the virtual server which disables further HTTP processing when they are seen.

How to use this snippet:

Note: You may have to disable the "HTTP::enable" command with a comment if using the iRule on an APM protected virtual service.

Code :

when CLIENT_ACCEPTED {
   # Enable HTTP processing for all requests by default
   HTTP::enable
}
when HTTP_REQUEST {
   # selectively disable HTTP processing for specific request methods
   switch [HTTP::method] {
      "MOVE" -
      "COPY" -
      "LOCK" -
      "UNLOCK" -
      "PROPFIND" -
      "PROPPATCH" -
      "MKCOL" { HTTP::disable }
   }
}