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    Prevent some LAN devices from being accessable over L2TP/IPsec

    Firewalling
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      Sorry.  I haven't revisited it.  It says right there in the wiki that a floating pass rule on L2TP VPN interface might be necessary.

      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)

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      • B
        BigApple
        last edited by

        Thank you  and yes that is certainly no problem at all. The problem is that after doing so I no longer have the ability to block access to certain LAN devices.
        Once the floating rule is in place … you can browse and you can access the entire network. In general that is a good idea... but I need to be able to block some machines from being accessible through the VPN connection.

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        • D
          doktornotor Banned
          last edited by

          @BigApple:

          Once the floating rule is in place … you can browse and you can access the entire network. In general that is a good idea... but I need to be able to block some machines from being accessible through the VPN connection.

          Looking at the wiki, that rule is direction Out. Not really sure how's that affecting you.

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          • B
            BigApple
            last edited by

            neither do i .. I just know I can no longer block access to the lan

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            • D
              doktornotor Banned
              last edited by

              Did you configure this as direction Out and not any? Plus, what's preventing you from using the Source/Destination to restrict this to what you want only?

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              • B
                BigApple
                last edited by

                I used out only but when I used ports 53, 80, 443 to allow browsing only on the floating rule it does not work (see sample)

                the floating rule only allows internet when any is selected …(see below)

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                • D
                  doktornotor Banned
                  last edited by

                  And why are those other rules floating? Leave the wiki one as floating direction out and put the rest where it belongs to restrict traffic. I really don't understand how we all of a sudden got to the "to allow browsing only ". You stated the goal is to "prevent some LAN devices from being accessable over L2TP/IPsec". This is the exact opposite direction.

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                  • B
                    BigApple
                    last edited by

                    my goal is to allow people to browse through the vpn ..but not access the lan network… but to allow browsing I need to turn on the floating rule (TCP any out)

                    when that is done... I can no longer prevent them from accessing the lan also.... the rules in the l2tp vpn tab no longer works

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                    • D
                      doktornotor Banned
                      last edited by

                      @BigApple:

                      the rules in the l2tp vpn tab no longer works

                      Yeah, those will never work… since, this tab is completely WRONG side of the tunnel. You need to move to the other firewall on the other end to block access to LAN. Or really dunno what "LAN network" are you talking about. Perhaps draw some diagram what are you trying to block where.

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                      • B
                        BigApple
                        last edited by

                        i have no other firewall in place only the pfsense unit. I only have VPN connections coming in… and there is no firewall that I know off...

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                        • D
                          doktornotor Banned
                          last edited by

                          @BigApple:

                          i have no other firewall in place only the pfsense unit. I only have VPN connections coming in… and there is no firewall that I know off...

                          Sorry, but floating rule with direction OUT will never apply to inbound traffic to the selected interface. You are doing this upside down. You cannot take the wiki rule as is and start restricting ports/IPs accessible on your LAN.

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            Read the language in the documentation again:

                            Firewall traffic blocked outbound

                            If the firewall logs show traffic blocked "out" on L2TP, then add a floating firewall rule to work around the block:

                            Navigate to Firewall > Rules, Floating tab
                                Click "+" to add a new rule
                                Set 'Action to Pass
                                Check Quick
                                Select L2TP VPN for the Interface
                                Set Direction to Out
                                Set Protocol to TCP
                                Set Source/Destination as needed, or set to any
                                Advanced Features:
                                    Set TCP Flags to Any flags
                                    Set State Type to Sloppy State

                            You should then control what your L2TP VPN clients can connect to with rules on your L2TP VPN tab.  if you only want them to get at TCP/UDP 53, TCP/80, and TCP/443 put those pass rules there.  Everything else will be blocked as it enters the firewall from the clients.  Except that it doesn't work.

                            I just tested it.  The floating rule is exactly as described above.  Direction OUT on L2TP VPN verified.  It appears the rules on the L2TP VPN tab are ignored.  Yes, I cleared states.

                            I can still SSH to 172.26.0.100 and the source address is the VPN client address 172.29.7.128.

                            ![Screen Shot 2015-05-23 at 10.32.20 AM.png](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.32.20 AM.png)
                            ![Screen Shot 2015-05-23 at 10.32.20 AM.png_thumb](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.32.20 AM.png_thumb)
                            ![Screen Shot 2015-05-23 at 10.31.10 AM.png](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.31.10 AM.png)
                            ![Screen Shot 2015-05-23 at 10.31.10 AM.png_thumb](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.31.10 AM.png_thumb)
                            pfSense+L2TP.png
                            pfSense+L2TP.png_thumb

                            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)

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                            • D
                              doktornotor Banned
                              last edited by

                              Yeah, of course they will get ignored when you tick the "Quick" checkbox on the floating rule.

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

                                Direction OUT.  The SSH connection is coming IN.

                                So you're saying the wiki is wrong?

                                https://doc.pfsense.org/index.php/L2TP/IPsec

                                And the floating rule is for TCP only.  I can still ping 172.26.0.100 despite the reject 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)

                                1 Reply Last reply Reply Quote 0
                                • D
                                  doktornotor Banned
                                  last edited by

                                  Sigh…

                                  1/ Check what sloppy state does.
                                  2/ Check the Set Source/Destination as needed - why on earth are you setting that as ANY when it obviously is NOT suitable for the intended purpose???

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                                  • DerelictD
                                    Derelict LAYER 8 Netgate
                                    last edited by

                                    Because without it set to ANY reply traffic to sides is blocked outbound.  This is with the rule disabled:

                                    ![Screen Shot 2015-05-23 at 10.57.25 AM.png](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.57.25 AM.png)
                                    ![Screen Shot 2015-05-23 at 10.57.25 AM.png_thumb](/public/imported_attachments/1/Screen Shot 2015-05-23 at 10.57.25 AM.png_thumb)

                                    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
                                    • DerelictD
                                      Derelict LAYER 8 Netgate
                                      last edited by

                                      The bottom line is rules on the L2TP VPN tab do not work like they work on every other VPN interface in pfSense.  They do not filter traffic coming INTO the firewall from VPN clients at the other end of the tunnel.

                                      For instance, with the floating rule disabled I can still ping 172.26.0.100 despite the explicit block rule on L2TP VPN.

                                      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
                                      • D
                                        doktornotor Banned
                                        last edited by

                                        I am not telling you to disable the rule. I am telling you to "Set Source/Destination as needed". When access to LAN in unwanted, obviously ANY is not proper?!?!?!?!?!?!?!?!?

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                                        • DerelictD
                                          Derelict LAYER 8 Netgate
                                          last edited by

                                          Explain how, with this explicit block rule, L2TP clients can ping 172.26.0.100.  The floating rule only applies to TCP traffic anyway so enabled or disabled makes no difference.  Let's forget about TCP and concentrate on ICMP.

                                          ![Screen Shot 2015-05-23 at 11.09.45 AM.png](/public/imported_attachments/1/Screen Shot 2015-05-23 at 11.09.45 AM.png)
                                          ![Screen Shot 2015-05-23 at 11.09.45 AM.png_thumb](/public/imported_attachments/1/Screen Shot 2015-05-23 at 11.09.45 AM.png_thumb)

                                          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
                                          • DerelictD
                                            Derelict LAYER 8 Netgate
                                            last edited by

                                            All rules on LT2P VPN tab disabled
                                            Floating sloppy rule disabled
                                            Only rule on IPsec tab passes UDP 1701 to WAN address
                                            States cleared

                                            Can still ping 172.26.0.100 from L2TP clients.

                                            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
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