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dwillis619_3073's avatar
dwillis619_3073
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Jun 08, 2017

Remove additional IP from XFF HTTP Header

I setup an LTM VIP with an iRule to XFF the client_addr in the HTTP header to destination but the traffic goes through a WAF. The WAF is adding a second IP to the HTTP Header which is the Float IP of...
application delivery
iRules
Morten_Marstran's avatar
Morten_Marstran
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Do you have control of all these devices? If so, is there any reason why you cannot remove the functionality that is inserting an XFF header on the WAF?

 

That way, you would only have the original client ip in the XFF header.

 

Morten_Marstran's avatar
Morten_Marstran
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Jun 13, 2017

Hi,

You could try this iRule on the backend LTM VIP. I haven't tested it, but it should work, as long as the ip's are split by a ","

when HTTP_REQUEST {
    if { [HTTP::header exists "X-Forwarded-For"] } {
        set original_ip [getfield [HTTP::header "X-Forwarded-For"] "," 1]
        HTTP::header replace "X-Forwarded-For" original_ip
    }
}