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    Using Open VPN service on XG-7100, prevent LAN clients connecting

    Scheduled Pinned Locked Moved Firewalling
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    • S
      shapelytraffic
      last edited by shapelytraffic

      I have a funny issue. If I attempt to connect to the VPN endpoint on the firewall, from inside the LAN, I am not rejected. Is this normal for Open VPN, what did I miss? I thought about a firewall rule, but the Open VPN interface is not an option for source or destination.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by Derelict

        Please rephrase your question. It doesn't make any sense.

        If you have an OpenVPN server listening on the WAN it is not designed to be connected to from the inside. It is designed to be connected to from the outside.

        Chattanooga, Tennessee, USA
        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
        Do Not Chat For Help! NO_WAN_EGRESS(TM)

        S JKnottJ 2 Replies Last reply Reply Quote 0
        • S
          shapelytraffic @Derelict
          last edited by

          @Derelict You're right it doesn't make any sense. I've never worked with a VPN endpoint that allows internal connections.

          I am using the Open VPN service on the XG-7100, VPN/Open VPN menu. The firewall is hosting the VPN server via the built in service. And yes, it allows connections from inside. Don't ask me how, because that's what I'm asking you. 🦆

          1 Reply Last reply Reply Quote 0
          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by Derelict

            Why connect from the inside? Why not just route the traffic?

            You can do it but if you are looking to be connecting from the inside, the network you are connecting from can't be one of the networks you expect to access over the VPN.

            You will see the same problems connecting from a remote site that uses the same IP numbering scheme as the protected network.

            So give more details:

            Subnet and IP address you are connecting from
            Subnet you expect to be routing over the VPN (The Local Networks in the server)
            The host IP address you are having trouble accessing.

            It is completely normal to be able to connect to services running on the WAN address from the inside. If you do not want that to happen you need to block connections to This firewall (self) on that interface. (Be sure the web gui is passed before that if you do or you will lock yourself out)

            Chattanooga, Tennessee, USA
            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
            Do Not Chat For Help! NO_WAN_EGRESS(TM)

            S 1 Reply Last reply Reply Quote 0
            • S
              shapelytraffic @Derelict
              last edited by

              @Derelict To be clear, I'm trying to disable connecting from the inside. We discovered this quite by accident.

              JKnottJ 1 Reply Last reply Reply Quote 0
              • S
                shapelytraffic
                last edited by

                My expectation when using a VPN endpoint on the firewall is that this endpoint will only accept traffic inbound from the WAN interface. How do I manually restrict the traffic that the Open VPN service will accept?

                1 Reply Last reply Reply Quote 0
                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by Derelict

                  Your expectation is erroneous.

                  Block the traffic on the interface(s) that are receiving the traffic you want blocked, such as the LAN interface.

                  A "guest" interface would look something like this:

                  Screen Shot 2017-08-06 at 2.26.11 PM.png

                  Chattanooga, Tennessee, USA
                  A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                  DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                  Do Not Chat For Help! NO_WAN_EGRESS(TM)

                  S 1 Reply Last reply Reply Quote 0
                  • S
                    shapelytraffic @Derelict
                    last edited by

                    @Derelict I'm not sure I've done a good job of expressing my concern. Can you repeat back to me what you understand my issue to be? I want to make sure that we are harmonized, because it seems like this should be very simple to solve.

                    S 1 Reply Last reply Reply Quote 0
                    • S
                      shapelytraffic @shapelytraffic
                      last edited by

                      Okay, so here's my beef: a VPN is designed to securely encapsulate private traffic to traverse a public network. Public and private are on opposite sides of the WAN interface. Since the Open VPN service accepts inbound connections from private interfaces, it is not working correctly.

                      Why does the PFSense implementation of Open VPN go against sane networking theory?

                      How do I stop the Open VPN from being naughty? Are you really saying I have to implement a ton of firewall rules to make the endpoint behave properly?

                      JKnottJ 1 Reply Last reply Reply Quote 0
                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        It is simple to solve. If you don't want users on an interface to connect to a service running on the firewall, make a block rule there.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

                        S 1 Reply Last reply Reply Quote 0
                        • S
                          shapelytraffic @Derelict
                          last edited by

                          @Derelict The endpoint should be accepting connections from private subnets by default. Why is it doing that?

                          1 Reply Last reply Reply Quote 0
                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            Because that WAN address is just another IP address. You need to block traffic from the inside to it if that's what your requirements are.

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

                            S 1 Reply Last reply Reply Quote 0
                            • S
                              shapelytraffic @Derelict
                              last edited by

                              @Derelict well, I'm not trying to block access to the WAN. I'm trying to prevent private subnets from connecting to the Open VPN service.

                              1 Reply Last reply Reply Quote 0
                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by Derelict

                                That is WAN address. That is not the internet. See the rule set I already posted.

                                Connections to the OpenVPN server would be blocked by the Reject Guest access to This Firewall rule.

                                Chattanooga, Tennessee, USA
                                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                Do Not Chat For Help! NO_WAN_EGRESS(TM)

                                S 1 Reply Last reply Reply Quote 0
                                • JKnottJ
                                  JKnott @Derelict
                                  last edited by JKnott

                                  @Derelict

                                  If you have an OpenVPN server listening on the WAN it is not designed to be connected to from the inside. It is designed to be connected to from the outside.

                                  Actually, that's normal. You can reach any address on the box from any interface, unless you have rules to block it. Don't forget, pfSense is a router, so if it, for example receives a packet with the WAN interface as destination, on the LAN interface, it will forward it appropriately through 0.0.0.0.

                                  PfSense running on Qotom mini PC
                                  i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                                  UniFi AC-Lite access point

                                  I haven't lost my mind. It's around here...somewhere...

                                  S 1 Reply Last reply Reply Quote 0
                                  • DerelictD
                                    Derelict LAYER 8 Netgate
                                    last edited by

                                    I know it's completely normal. It's @shapelytraffic that is having trouble grasping that concept.

                                    Chattanooga, Tennessee, USA
                                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

                                    1 Reply Last reply Reply Quote 0
                                    • S
                                      shapelytraffic @Derelict
                                      last edited by

                                      @Derelict I saw your rules, what are you representing with "guest" network?

                                      If I block LAN access to the WAN then I assume this will have global impact.

                                      JKnottJ 1 Reply Last reply Reply Quote 0
                                      • JKnottJ
                                        JKnott @shapelytraffic
                                        last edited by

                                        @shapelytraffic said in Using Open VPN service on XG-7100, prevent LAN clients connecting:

                                        @Derelict To be clear, I'm trying to disable connecting from the inside. We discovered this quite by accident.

                                        That behaviour is normal. If you don't want it, create a rule on the LAN interface to block it.

                                        PfSense running on Qotom mini PC
                                        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                                        UniFi AC-Lite access point

                                        I haven't lost my mind. It's around here...somewhere...

                                        1 Reply Last reply Reply Quote 0
                                        • DerelictD
                                          Derelict LAYER 8 Netgate
                                          last edited by

                                          No. It won't have global impact. Global addresses are not covered in any of those block rules. Traffic that is not specifically blocked will be passed to the internet by the bottom rules passing traffic to destination any. Guest Network in that example is the IP network of the GUEST interface.

                                          Chattanooga, Tennessee, USA
                                          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                          Do Not Chat For Help! NO_WAN_EGRESS(TM)

                                          S 1 Reply Last reply Reply Quote 0
                                          • S
                                            shapelytraffic @JKnott
                                            last edited by

                                            @JKnott my issue is that any other router on the market which provides a VPN endpoint and client install will only accept client traffic from the public side of the WAN. You cannot go in through the outdoor, as it were. So, if this is "a feature" then I ask, why is it that the feature goes against networking standards? But also, do I really need to implement a ton of firewall rules to make the endpoint behave?

                                            JKnottJ 2 Replies Last reply Reply Quote 0
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