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    Firewall rules ignored or overridden?

    Scheduled Pinned Locked Moved Firewalling
    46 Posts 4 Posters 11.9k Views
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    • DerelictD Offline
      Derelict LAYER 8 Netgate
      last edited by

      Those are always there. I don't think that's it.

      From the PM'd pcap it looks like IPv6 is working and IPv4 is broken. That is probably the difference between the different IMAP servers.

      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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      • DerelictD Offline
        Derelict LAYER 8 Netgate
        last edited by

        Yeah. the presence of AAAA records corresponds to the servers you report as working. The ones that fail do not have AAAA records.

        So un-do whatever you did for IPv4 and make it look like IPv6 and you should be GTG. :)

        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 Offline
          deadbolt_forum
          last edited by

          Not so easy.

          Floating Rules:
          All rules here are pass or match and unrelated.

          WAN Rules:
          All rules here are pass except for pfsense's block RFC1918 and block bogons.

          LAN Rules:
          All rules here are pass except for NETBIOS on my network.
          Also, the rule allowing traffic bound for 993 is an IPv4+6 rule so if it is passing v6 traffic then presumably it is passing v4 traffic as well.

          Unless there are some other hidden rules then that is everything.

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          • johnpozJ Offline
            johnpoz LAYER 8 Global Moderator
            last edited by

            Yeah looks like you have ipv6 working, but don't see the start of that conversation.  But looks like all your ipv4 is borked..

            Where exactly did you sniff this??  Looks like syn,ack is sent from public to a private.. But no answer??

            torfc1918.png
            torfc1918.png_thumb

            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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            • DerelictD Offline
              Derelict LAYER 8 Netgate
              last edited by

              Not sure what to tell you, man. You screwed the pooch somewhere along the way.

              Send your /tmp/rules.debug

              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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              • johnpozJ Offline
                johnpoz LAYER 8 Global Moderator
                last edited by

                That is a microsoft IP..  Clearly its sending a syn,ack to private IP address. So that was on the LAN of pfsense??  Where was this sniff taken?

                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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                • DerelictD Offline
                  Derelict LAYER 8 Netgate
                  last edited by

                  You don't have like LAN and WAN on the same dumb switch or something do you? Something's not right there. It's like that capture contains both pre-nat and post-nat replies.

                  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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                  • johnpozJ Offline
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    So yeah this is odd..  Looks like wan sniff showing your public IP sending syn to the public IP.  And you see the syn,ack back.  And then you see the syn,ack sent on to the rfc1918 address??  But then you see a retrans of the syn back to the server from your public..

                    So the client never saw the syn,ack so its resending syn..  But if we are seeing the lan side of this - where was the syn from the client?

                    Need to understand where you sniff this at..  Something is not right here.. If we were seeing both wan and lan sides of the sniff.. Then we should of seen the incoming syn to to the pfsense lan, and then it going out the public, then the syn,ack coming back, and then it going out the lan, etc..  But where is the original syn from the 192.168.1.40 addess if that is the case??

                    You got some sort of asymmetrical issue going on??  Where the syn from the client is coming into pfsense, but its sending the traffic back to the client on wrong interface?  But where exactly are you sniffing that seeing both wan and lan traffic?

                    odd.png
                    odd.png_thumb

                    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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                    • D Offline
                      deadbolt_forum
                      last edited by

                      Sorry for the delay.

                      The issue where I could not telnet to port 993 was caused by a Floating Pass rule allowing outbound traffic to TCP 993 in an attempt to solve the original issue.  It is counter intuitive that a pass rule would cause traffic to get blocked however it looks like the floating rule prevented the TCP session which was originally allowed by the LAN rule passing TCP 993.

                      Although I can now telnet successfully to mailservers on port 993, the original issue still persists.  See screenshot.  I am trying to come up with an appropriate packet capture that I can provide to show this however I am having trouble sanitizing the capture to not reveal private information.

                      993.png
                      993.png_thumb

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                      • johnpozJ Offline
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        What is you want to pull out of the capture, or what do you want to change in like IP?

                        Normally best thing is to capture only want you want to share.. Changing the IP of is quiet easy with say https://www.tracewrangler.com/ or bit-twist.

                        As to your original issue.. All of those blocks you list are out of state.. FA, RA… To what your rules are doing? I don't see how a floating allow would prevent a lan allow?  If you have floating and lan rules that do the same thing??  Its possible doing such a thing could lead you to a state of something being closed and then being seen on as out of state??

                        Really would need to fully understand your flow of traffic, making sure you don't have loops, and your firewall rules.  If your PM to me was to say your sniff on the lan.. Then how were you seeing packets with wan address??  You got something clearly borked that is for sure..

                        A lan sniff should not show you wan traffic..  But in that sniff see SYN from public IP to your public dest..  Its like maybe you have some sort of issue where your running your wan over your lan layer 2?  But yeah if pfsense sense is seeing a FIN to close the state, and then sees another FIN to close the state it already closed then it would be out of state and listed as a block..

                        This seems like what is happening.  Your sniff if that was on the LAN of pfsense or some other device or port on your LAN.. It should be impossible to see your public IPs.. But they were in there along with rfc1918 address of 192.168.1.40??

                        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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