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Daniel_Abrahams's avatar
Daniel_Abrahams
Icon for Nimbostratus rankNimbostratus
Feb 18, 2021

Require host header

Hi,   Is there a setting/iRule that makes it so that host header is required for clients to be able to connect to server. For example User enters https://www.test.com he will be able to connec...
BIG-IP Access Policy Manager (APM)
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Daniel_Wolf's avatar
Daniel_Wolf
Icon for MVP rankMVP
Feb 18, 2021

Hi  ,

I have a bit more general approach than  . It will use a regex instead of hard coded IP address.

Tested on 15.2 and seems to do what it is supposed to do.

when HTTP_REQUEST {
    if { [scan [HTTP::host] %d.%d.%d.%d a b c d] == 4 && 0 <= $a && $a <= 255 && 0 <= $b && $b <= 255 && 0 <= $c && $c <= 255 && 0 <= $d && $d <= 255} {
        #log local0. "Invalid hostname: [HTTP::host]"
        drop
    } else {
        #log local0. "Valid hostname: [HTTP::host]"
        return
    }
}

The regex I simply stole from here: wiki.tcl-lang.org >> Regular Expression Examples

It is supposed to check whether the string in HTTP::host matches the syntax of an IP address.