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    LAN ip blocked but seems to be passing traffic

    Scheduled Pinned Locked Moved Captive Portal
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    • h1pp13p373H
      h1pp13p373 @h1pp13p373
      last edited by

      Just found hastebin... pretty slick. Even a cli client so you can pipe stuff to it.
      https://hastebin.com/about.md

      So, back to my original issue, here's my dump and rules:
      https://hastebin.com/elamojuvaw.coffeescript

      I'd found an old pfsense thread that suggested I place a specific allow for that alias before the block but that didn't work either. I still could see traffic being passed.

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

        Please paste /tmp/rules.debug

        Establish a connection that should be blocked. While connected or immediately thereafter get the output of this:

        pfctl -vvss | grep -A 3 192.168.42.89

        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)

        h1pp13p373H 1 Reply Last reply Reply Quote 0
        • h1pp13p373H
          h1pp13p373 @Derelict
          last edited by

          @Derelict Got it:
          https://hastebin.com/pocurolagi.coffeescript

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

            Great. Now:

            pfctl -vvsr | grep -A3 '^@24('

            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)

            h1pp13p373H 1 Reply Last reply Reply Quote 0
            • h1pp13p373H
              h1pp13p373 @Derelict
              last edited by

              @Derelict Newest at the top:

              https://hastebin.com/umedifopej.coffeescript

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                Great. Do you have a captive portal on that interface?

                What are the various IP address and MAC address pass throughs 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)

                h1pp13p373H 1 Reply Last reply Reply Quote 0
                • h1pp13p373H
                  h1pp13p373 @Derelict
                  last edited by

                  @Derelict Good thinking! I do have a captive portal active, but I only have a few ip's allowed and 192.168.42.89 is not on the allowed list. I don't have any allowed MAC addresses set.
                  https://hastebin.com/ifabayekin.coffeescript

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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    Well that's probably why you're seeing what you're seeing. I am not sure why yet but those sloppy rules are likely the culprit. Note that there is no state shown that passes traffic into LAN from 192.168.42.89:39163 -> 99.193.64.55:80. Only the reply traffic passed by sloppy rule 24.

                    Turn off the captive portal. Is the traffic blocked?

                    Move the specific block rule to the top of the rule set. Is the traffic blocked?

                    Most people would not stack a bunch of stuff on an interface with a portal on it. They'd create two different security zones (interfaces) and put the captive portal on one and the hosts that should be able to pass through on the other.

                    What is the output of ipfw show

                    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)

                    h1pp13p373H 1 Reply Last reply Reply Quote 1
                    • h1pp13p373H
                      h1pp13p373 @Derelict
                      last edited by

                      @Derelict said in LAN ip blocked but seems to be passing traffic:

                      ipfw show

                      https://hastebin.com/isadazabew.coffeescript

                      Looks like that was the culprit! After turning the portal off, I didn't see any return traffic from the remote ip. I guess the portal returning the login page looked like a return from the remote ip in the dump...? Strange though. I sure appreciate your help, @Derelict !!

                      I'm also going to look into security zones like you suggested. Is the purpose of using the zones to have an abstract layer of trusted and untrusted hosts sort of like aliases for fw rules, or is it a performance thing?
                      I was a linux guy for years and know just enough networking to be dangerous. :)

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

                        The purpose is to segment secure portions of your network from each other, each with the capabilities necessary for that segment (like captive portal).

                        Yes, the captive portal page being returned would look like that if you were capturing on LAN. I (and everyone else probably) assumed you were looking at a web browser when you were testing and seeing the portal page instead of the outside site would have seemed like an obvious clue to me.

                        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)

                        h1pp13p373H 1 Reply Last reply Reply Quote 1
                        • h1pp13p373H
                          h1pp13p373
                          last edited by

                          Thanks again, and that makes sense about segmenting.

                          This all started when I saw traffic to that LAN ip on ntopng (installed on the pfsense box) and did a pcap download. That's where I saw the traffic from the remote ip to the LAN address and I got concerned. The 302 should have also gave me a clue about the portal.
                          The portal was only set up to rick roll guests and I guess I deserve it for that. lol
                          Have a great day!

                          1 Reply Last reply Reply Quote 0
                          • h1pp13p373H
                            h1pp13p373 @Derelict
                            last edited by

                            @Derelict I'm having trouble finding documentation on using interfaces to segment. Is it like creating virtual interfaces and assigning ip lists to one or both? Would you mind linking me an article?

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

                              This discusses network segmentation:

                              https://www.youtube.com/watch?v=QFk5jX-oeSo

                              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)

                              h1pp13p373H 1 Reply Last reply Reply Quote 0
                              • h1pp13p373H
                                h1pp13p373 @Derelict
                                last edited by

                                @Derelict Thanks!

                                1 Reply Last reply Reply Quote 0
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