cond %{SEND_REQUEST_HDR_HOOK} [AND]
    set-header X-From-Client "%{CLIENT-HEADER:X-Source}"
    set-header X-From-Server "%{SERVER-HEADER:X-Source}"

cond %{READ_RESPONSE_HDR_HOOK} [AND]
    set-header X-From-Client "%{CLIENT-HEADER:X-Source}"
    set-header X-From-Server "%{SERVER-HEADER:X-Source}"

cond %{SEND_RESPONSE_HDR_HOOK} [AND]
    set-header X-From-Client "%{CLIENT-HEADER:X-Source}"
    set-header X-From-Server "%{SERVER-HEADER:X-Source}"
