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    Real IP-addresses behind OpenVPN - why do I not see them in my logs?

    Scheduled Pinned Locked Moved OpenVPN
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    • V Offline
      viragomann
      last edited by

      If you see the VPN clients IP on server side, obviously the NAT occurs in the ASUS box, when packets leaving it to the virtual vpn interface.

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      • T Offline
        tsmalmbe
        last edited by

        OK, here's the config. There are really no settings for setting NAT's etc in the Asus-box though. Although pricey, in many categories it's plain and simple.

        
        dev tun
        persist-tun
        persist-key
        proto udp
        cipher AES-128-CBC
        auth SHA256
        resolv-retry infinite
        remote 217.30.666.666 1196
        route 192.168.1.0 255.255.255.0
        route 10.10.1.0 255.255.255.0
        route 10.99.0.0 255.255.0.0
        route 194.100.666.666 255.255.255.255
        ifconfig 10.100.101.2 10.100.101.1
        keepalive 10 60
        ping-timer-rem
        comp-lzo
        verb 5
        [code][/code]
        

        Security Consultant at Mint Security Ltd - www.mintsecurity.fi

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        • V Offline
          viragomann
          last edited by

          That is the OpenVPN config. NAT is no part of OpenVPN.

          Some routers do source NAT on upstream interfaces which can not be switched off. In pfSense this is done by outbound NAT and it's not set by default.

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          • T Offline
            tsmalmbe
            last edited by

            OK, so no way to override any NAT rules using OpenVPN configurations. As I thought. I guess it is not worth looking into this any further, just to accept the facts.

            Security Consultant at Mint Security Ltd - www.mintsecurity.fi

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            • johnpozJ Offline
              johnpoz LAYER 8 Global Moderator
              last edited by

              "I would like to be able to create all my firewall rules with src=win7 instead of src=tunneaddress."

              Then you need to this client to connect to a router that has tunnel, not as a direct vpn client.

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 24.11 | Lab VMs 2.8, 24.11

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              • T Offline
                tsmalmbe
                last edited by

                @johnpoz:

                "I would like to be able to create all my firewall rules with src=win7 instead of src=tunneaddress."

                Then you need to this client to connect to a router that has tunnel, not as a direct vpn client.

                My Win7-computer is connecting to a router (Asus) which has a site-2-site tunnel to my main site (pfSense). So, connecting to a router that creates the tunnel does not seem to be a solution.

                Security Consultant at Mint Security Ltd - www.mintsecurity.fi

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                • johnpozJ Offline
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  What IP are you expecting to see??

                  Lets get some details here..

                  So your win7 box is on a network lets call it 192.168.0/24 and your tunnel network, lets call it 10.0.8/24, and your webserver is on say 192.168.1/24

                  What IP are you seeing where??  If your tunnel was setup correctly or how it would normally be done your webservers logs would see 192.168.0.x..  If your seeing a 10.0.8.x address then your natting to the tunnel IP..

                  So your saying on the win7pc side if you ping from say your server on 192.168.1.x win7 sees the 192.168.1 address..  But when you access something off your webserver its logs are showing the 10.0.8 address?

                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                  If you get confused: Listen to the Music Play
                  Please don't Chat/PM me for help, unless mod related
                  SG-4860 24.11 | Lab VMs 2.8, 24.11

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                  • T Offline
                    tsmalmbe
                    last edited by

                    This is exactly correct. I am currently assuming this is built in NAT feature in the Asus client, a feature which I cannot control.

                    Security Consultant at Mint Security Ltd - www.mintsecurity.fi

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                    • johnpozJ Offline
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      Well if its natting then its not really a site to site, but just a client connection..  Like when you setup pfsense to use a vpn service..  Pfsense nats all your clients on your network to your tunnel IP so the vpn service knows what connection the traffic is from, etc.

                      But a site to site connection is just a transit network, you would not need to nat this.  Use something better on the client side that allows you to actually create a site to site and route, say pfsense ;) for example..

                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                      If you get confused: Listen to the Music Play
                      Please don't Chat/PM me for help, unless mod related
                      SG-4860 24.11 | Lab VMs 2.8, 24.11

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                      • T Offline
                        tsmalmbe
                        last edited by

                        Yes, I find it wierd behavior. But the device is otherwise good - and this has to be a one device environment. Asus AC-55U. It's got proper syslogging, good wifi and good 4G with antenna support. Compared to others, this is enterprisey. And comes with a OpenVPN -client built in. The specs with just one device is pretty unbeatable.

                        I hate the NATtin though, and hope to find some obvious misconfiguration being the reason.

                        Security Consultant at Mint Security Ltd - www.mintsecurity.fi

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