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    DNS Resolver Leaking and DHCP addresses

    Scheduled Pinned Locked Moved DHCP and DNS
    43 Posts 5 Posters 3.6k Views
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @disgrun
      last edited by johnpoz

      @disgrun because you created a firewall rule that blocks 1.1.1.1..

      Again - look in that table pfb_ in your diagnostic menu.. Do you see 1.1.1.1 in it, if so then it would be blocked.. But it doesn't so its not.

      btw - hiding rfc1918 addresses is pretty pointless.. And you missed one there at the bottom.. what do you think anyone could do with a 192.168 address, they do not route on the internet, they say nothing about even what ISP your using, etc. etc.. This is like saying hey I live on a street with address 123.. Well yeah pretty much every street on the planet will have numbers as addresses on them. But knowing that its 123 on some street doesn't help you find the actual 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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        disgrun @johnpoz
        last edited by

        @johnpoz as you can see pfsense does block the website

        99708a43-270a-4f38-aa0a-017643c527ec-image.png

        but when the website is blocked 1.1.1.1:443 or 1.1.1.1:80 try to get through.

        Is this normal?

        johnpozJ 1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @disgrun
          last edited by johnpoz

          @disgrun not sure what your not understanding how dns works?

          pfblocker and unbound can be set to not resolve something, or send you a wrong IP so you can't actually get there. But this is only the resolution of the fqdn to the IP.. This does not stop actual traffic to the IP.. Only a firewall rule will do that, and for the firewall rule to block, it has to trigger..etc..

          Do yourself a favor and look in that pf_ table in your floating tabs in tables under the diagnostic menu..

          remove your block rule you created on your office interface and go to https://1.1.1.1 vs the name one.one.one.one

          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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            disgrun @johnpoz
            last edited by disgrun

            @johnpoz went right through without the patch rule.

            a65d596e-980c-4e8a-a05c-6b4c61012579-image.png

            and website still blocked by pfsense

            a9697345-6330-4452-84b9-751f0d7abd72-image.png

            johnpozJ 1 Reply Last reply Reply Quote 0
            • johnpozJ
              johnpoz LAYER 8 Global Moderator @disgrun
              last edited by johnpoz

              @disgrun exactly - so what part are you not getting.. see that NXdomain, that says that one.one.one.one did not resolve...

              So what part are you not getting? you understand that some fqdn like www.netgate.com has to resolve to an IP to actually talk to it right.. But if you know the IP you can talk to that IP without having to look up the ip via dns.

              If your client says hey I want to use doh with site called one.one.one.one and it doesn't resolve it can't get there, but if it just goes to the actual IP 1.1.1.1 unbound, ie resolving that fqdn is not involved.. Only firewall rules that actually block to IP or port would be involved.

              That is why when you created a firewall that blocks access to 1.1.1.1 it fails, doesn't matter if the client looks it up from one.one.one.one or googledns or clouddns.org or whatever - you ain't talking to that IP.

              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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                disgrun @johnpoz
                last edited by

                @johnpoz Hi, Ok, I think i got it . Everything is working great, the 1.1.1.1 i am seeing is NOT a dns, entry it is a website address. So the DNS is being redirected but I am seeing the 1.1.1.1 since it is the address of the website. I think that solves it!

                Thank you! Your help was greatly appreciated!

                Hopefully you can give me an answer to my second part of the post.

                Why do I see ipv6 address for all my devices even though ipv6 is off. I always thought pfsense handed out all the addresses to my devices.

                Some devices even have more than one ipv6 address.

                Thanks!

                johnpozJ 1 Reply Last reply Reply Quote 0
                • johnpozJ
                  johnpoz LAYER 8 Global Moderator @disgrun
                  last edited by johnpoz

                  @disgrun what IPv6 address?

                  Like this?

                  linklocal.jpg

                  Pretty much any modern device will have those, unless you on purpose disable IPv6 on it - like this

                  disabled.jpg

                  Yes an actual GUA would come from pfsense, be it via dhcpv6 or slaac

                  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
                    disgrun @johnpoz
                    last edited by disgrun

                    @johnpoz Is there no way to stop/disable them with pfSense?

                    Or can i do it via Terminal screen in linux?

                    405bae31-ee24-4eb8-b3e4-073c80b33330-image.png

                    b73c576b-e3d4-4e1a-a20c-bbd93b478cfa-image.png

                    How is netflix getting an iPV6 address from me?

                    Netflix.png

                    johnpozJ 1 Reply Last reply Reply Quote 0
                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @disgrun
                      last edited by johnpoz

                      @disgrun hiding the IP address doesn't help me determine if that is link local or not.. just the first part does it start with fe80, then its link local and doesn't route on the internet.

                      If you have IPv6 on pfsense, dhcpv6 is not the only way clients get IPv6 - look up slaac

                      And yes one of the things about IPv6 is clients using multiple addresses.

                      Your clients could get address all day, but if you don't allow them out then they are not going anywhere with it.

                      Delete this rule on your office for example

                      yourrule.jpg

                      But notice the 0/0 B there on its left - that means its never been evaluated. So nothing on your office network has used IPv6 to go anywhere out on the internet.

                      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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                        disgrun @johnpoz
                        last edited by

                        @johnpoz Untitled.png

                        I deleted the ipv6 rules and some of the ipv6 addresses went away. But as seen in pic, why is this device still getting an ipv6 address, even if it is a local one since pfsense did not lease one out?

                        Thanks,

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @disgrun
                          last edited by

                          @disgrun that is link local, as I mentioned pretty much any modern OS or device that supports IPv6 will always have those..

                          https://en.wikipedia.org/wiki/Link-local_address

                          Almost impossible to make those go away on some OSes or Devices, even if you on purpose disable its ipv6 support

                          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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                            disgrun @johnpoz
                            last edited by

                            @johnpoz Thank you for your help, I learned alot! Take are.

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