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jay_41157's avatar
jay_41157
Icon for Nimbostratus rankNimbostratus
Apr 21, 2011

HTTP::PAYLOAD

HI,

I am trying to replace the page content with x's however I am running into some issues and not sure what to do..

Please help.

here is the error i see in the ltm log file:


Apr 21 16:28:16 local/tmm err tmm[4788]: 01220001:3: TCL error: parse_test_irule  - Out of bounds (line 2)     invoked from within "HTTP::payload replace 0 $content_length [string repeat "X" $content_length]"
Apr 21 16:28:53 local/tmm1 err tmm1[4789]: 01220001:3: TCL error: parse_test_irule  - Out of bounds (line 6)     invoked from within "HTTP::payload replace 0 $content_length [string repeat "X" $content_length]"
Apr 21 16:29:26 local/tmm err tmm[4788]: 01220001:3: TCL error: parse_test_irule  - Out of bounds (line 2)     invoked from within "HTTP::payload replace 0 $content_length [string repeat "X" $content_length]"

Here is what my irule looks like, I got it from the WIKI page examples...


when HTTP_RESPONSE {
   Only check responses that are a text content type (text/html, text/xml, text/plain, etc).
  if { [HTTP::header "Content-Type"] starts_with "text/" } {
     Get the content length so we can collect the data (to be processed in the HTTP_RESPONSE_DATA event)
     Limit collection to 1Mb (1048576 minus a little to spare) - See SOL6578 for details
    if { [HTTP::header exists "Content-Length"] } {
      if { [HTTP::header "Content-Length"] > 1048000 }{
         Content-Length over 1Mb so collect 1Mb
        set content_length 1048000
      } else {
         Content-Length under 1Mb so collect actual length
        set content_length [HTTP::header "Content-Length"]
      }
    } else {
       Response did not have Content-Length header, so use default of 1Mb
      set content_length 1048000
    }
     Don't collect content if Content-Length header value was 0
    if { $content_length > 0 } {
       HTTP::collect $content_length
    }
log local0. "Payload Length:[HTTP::payload length]:"
log local0. "Content Length:[HTTP::header value Content-Length]:"
log local0. "Payload:[HTTP::payload]:"
  }
}
when HTTP_RESPONSE_DATA { 
    log "Replacing payload with new data."  
      HTTP::payload replace 0 $content_length [string repeat "X" $content_length]
    [HTTP::release]
}

Thanks,

Jay

application delivery
dev
devops
iRules

3 Replies

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  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Apr 22, 2011
    what software version r u running? does the error always happen or sometime? do u know if server sends chunked response?
  • jay_41157's avatar
    jay_41157
    Icon for Nimbostratus rankNimbostratus
    Apr 22, 2011
    version 10.2 HF2; not sure if the server sends chunked response... the vip has response chunking enabled using a profile.
  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Apr 22, 2011
    You could prevent chunking on server responses (which will break the iRule as no content-length header is set) by setting the HTTP version in the request to 1.0: 

    
 Poached from http://devcentral.f5.com/wiki/default.aspx/iRules/CreditCardScrubber.html
when HTTP_REQUEST {

    Prevent the server from sending a compressed response
    remove the compression offerings from the client
   HTTP::header remove "Accept-Encoding"

    Don't allow response data to be chunked
   if { [HTTP::version] eq "1.1" } {

       Force downgrade to HTTP 1.0, but still allow keep-alive connections.
       Since HTTP 1.1 is keep-alive by default, and 1.0 isn't,
       we need make sure the headers reflect the keep-alive status.

       Check if this is a keep alive connection
      if { [HTTP::header is_keepalive] } {

          Replace the connection header value with "Keep-Alive"
         HTTP::header replace "Connection" "Keep-Alive"
      }

       Set server side request version to 1.0
       This forces the server to respond without chunking
      HTTP::version "1.0"
   }
}

    Aaron