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f5gurunot's avatar
f5gurunot
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Feb 02, 2023
Solved

TCP Option 28 X-Forwarded-For Header

Using Akamai for DDOS mitigation and the requests sent to us show Akamai IP instead of the Client IP.  I have enabled TCP Option 28 and trying to insert the Client IP into X-Forwarded-For header.  I ...
  • xuwen's avatar
    xuwen
    Feb 03, 2023

    when CLIENT_DATA {
    set opt28 [TCP::option get 28]
    if { [string length $opt28] == 4 } {
    binary scan $opt28 H8 addr
    scan $addr "%2x%2x%2x%2x" ip1 ip2 ip3 ip4
    set optaddr "$ip1.$ip2.$ip3.$ip4"
    log local0. "optaddr is $optaddr"
    log local0. "ip addr parse result is [IP::addr parse -ipv4 $opt28]"
    }
    }