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Ross_Fitheridge's avatar
Ross_Fitheridge
Icon for Nimbostratus rankNimbostratus
Nov 09, 2007

rewrite absolute URI to relative URI

we are having difficulty with a Virtual Server, that is configured for SSL server off-load. Most clients work, however we have one (the most important (of course) that comes through a Proxy). The Squid Proxy makes a call using an absolute URI with the protocol HTTPS: (https://www.company.com:8443/service), however the server only understands HTTP. The LTM is not translating the URI from https to http.

 

 

If I could just change the URI from https to http it would do the job.

 

 

I have attempted to rewrite the URI from an absolute to a relative URI, but this is not working. When I log the URI before and after it is still the same. The iRule I am trying follows:

 

 

Rule to modify absolute URI to relative URI

 

when HTTP_REQUEST {

 

set relativeUri "[URI::path [HTTP::uri]][URI::basename [HTTP::uri]][HTTP::query]"

 

HTTP::uri $relativeUri

 

}

 

 

I thought this was going to be simple, and I hope you are going to show me it is :-)
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  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Nov 09, 2007
    The value for HTTP::uri is cached, so you won't see the update. If you log the value for $relativeUri, is it what you expect?

    Also, I would expect that the web server(s) in the pool would be able to parse an absolute URI, so you could just replace https:// with http:// using string map, instead of using all of the URI:: and HTTP:: commands. Here's an example to log the pre- and post-change URIs:

    
 Rule to modify absolute URI to relative URI
when HTTP_REQUEST {
   set relativeUri "[URI::path [HTTP::uri]][URI::basename [HTTP::uri]][HTTP::query]"
   log local0. "Original URI: [HTTP::uri], modified URI: $relativeUri"
   HTTP::uri $relativeUri
}

    And here's an example that just replaces the https: with http:, keeping the absolute URI:

    
 Rule to modify absolute URI from HTTPS to HTTP
when HTTP_REQUEST {
    Use string map to replace "https:" with "http:" in the URI
   set modifiedUri [string map {https: http:} [HTTP::uri]]
   log local0. "Original URI: [HTTP::uri], modified URI: $modifiedUri"
   HTTP::uri $modifiedUri
}

    Once you have it tested, you can remove the logging and variable:

    
 Rule to modify absolute URI from HTTPS to HTTP
when HTTP_REQUEST {
    Use string map to replace "https:" with "http:" in the URI
   HTTP::uri [string map {https: http:} [HTTP::uri]]
}

    Aaron
  • Deb_Allen_18's avatar
    Deb_Allen_18
    Historic F5 Account
    Nov 09, 2007
    HTTP::uri is supposed to return a string containing the location + query string.

     

     

    If you are seeing that it isn't, what version are you on?
  • Ross_Fitheridge's avatar
    Ross_Fitheridge
    Icon for Nimbostratus rankNimbostratus
    Nov 12, 2007
    Hi Deb,

     

    the Version is 9.1.2

     

     

    The URI does not return the query string. it seems in the code I original wrote I had the query string duplicated!

     

     

    This is the code I am using to prove this is .....

     

    when HTTP_REQUEST {

     

    Use string map to replace "https:" with "http:" in the URI

     

    set modifiedUri [string map {https: http:} [HTTP::uri]]

     

    set relativeUri "[URI::path [HTTP::uri]][URI::basename [HTTP::uri]]"

     

    log local0. "Original URI: [HTTP::uri], modified URI: $modifiedUri , Relative Uri: $relativeUri , IP: [IP::client_addr], HTTP Query: [HTTP::query]"

     

    HTTP::uri $modifiedUri

     

    }

     

    And a log entry ....

     

    Nov 12 08:44:56 tmm tmm[738]: Rule uri_https_to_http : Original URI: https://partneruat.acmebusiness.com:8443/OTAService/, modified URI: http://partneruat.acmebusiness.com:8443/OTAService/ , Relative Uri: /OTAService/ , IP: 129.35.201.38, HTTP Query: xml

     

     

    RossF