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    IPv6 EUI-64??

    Scheduled Pinned Locked Moved IPv6
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    • JonathanLeeJ
      JonathanLee @JKnott
      last edited by JonathanLee

      @JKnott thanks for the reply. per network fundamentals, EUI-64 at its basics takes the a clients 48bit MAC address and utilizes it in a IPv6 addressing scheme, devices have a hardware address that is vendor assigned into the MAC address that is what is used. However it can be done in different ways it seems…

      Don’t quote me on this part, I think every IPv6 has the MAC address ciphered into the address temp or not it just is masked better. The original design is for tracking logs etc. it is just sugar coated now makes everyone feel better about it. The DUID (Device Unique Identifier) is still coded into the IPv6 addresses. I think they use different ciphers for IPv6 unknowingly. No one gets untraceable untrackable devices, how could anyone call anyone else if that was the case. It needs some way to find a device on a network.

      In pfSense If you test out turning on or off the directives shared with us, you can see the DUID will include a vendor MAC address into it with clear text, the IPv6 address just masks it better with the DUID. If you set that directive to zero only part of the MAC is included in the DUID, and if you turn the directive to on or 1 it is fully visible under leases area you can see the DUID matches a MAC address. It gets rid of arp request this way.

      Make sure to upvote

      johnpozJ JKnottJ 2 Replies Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator @JonathanLee
        last edited by

        @JonathanLee said in IPv6 EUI-64??:

        MAC address ciphered into the address temp or not it just is masked better.

        BS.. and this would be done on the client anyway.. Not pfsense..

        Why would you think there is something in the pfsense to tell the client how to create their IPv6 address when using 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 2.7.2, 24.11

        JonathanLeeJ 1 Reply Last reply Reply Quote 0
        • JonathanLeeJ
          JonathanLee @johnpoz
          last edited by JonathanLee

          @johnpoz test it you can see the DUID change and it will show a MAC address. The only reason pfSense would let you adapt the DUID in that way is to save time with static IPv6 dhcp addressing. If the directives are turned on the MAC address is inside the DUID in clear text without it on it’s seems to only include two parts of the MAC address in DUID on my system. New to me… again I could be wrong. PfSense would allow you adapt the DUID, just like pfSense gives you the ability to create private addresses and subnets. this adjustment is on the IPv6 dhcp so it’s this is used for private addresses or lan side assignments side. With Non SLAAC.

          Is SLAAC public assignments? SLAAC is stateless management right?

          I am talking about dhcp of ipv6 where duid is used. They have an algorithm that does not mask the MAC address makes it clear in duid before the ipv6 dhcp lease and creations.

          IMG_0982.jpeg
          https://datatracker.ietf.org/doc/html/rfc6939
          https://datatracker.ietf.org/doc/html/rfc6355
          https://www.rfc-editor.org/rfc/rfc8415

          They do have RFC info for DUID and Mac addressing. IPv6 still makes my head hurt. Again If you can spoof a Mac what good is the secure side of it …

          Make sure to upvote

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          • JonathanLeeJ
            JonathanLee @johnpoz
            last edited by

            @johnpoz your right they do change the MAC addresses your right they also spoof them today. Again if a 48 mac is hard coded into a network interface there must be a way to know the differences. Vendor ID is key

            Make sure to upvote

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

              @JonathanLee said in IPv6 EUI-64??:

              Don’t quote me on this part, I think every IPv6 has the MAC address ciphered into the address temp or not it just is masked better.

              Ooops! I quoted you! 😉

              An IPv6 address can use either the MAC address or a random number, your choice. As I mentioned, with SLAAC, you can have up to 8 global addresses. One is consistent and would be used for servers, etc.. The other 7 are always based on a random number and used when you connect to somewhere else. So, when you go to a web site, you will be using the most recent of the 7 temporary addresses.

              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 1
              • JKnottJ
                JKnott @JonathanLee
                last edited by

                @JonathanLee said in IPv6 EUI-64??:

                Vendor ID is key

                So, you're saying a vendor couldn't make, for example, both an Ethernet and Firewire interface? I doubt 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...

                JonathanLeeJ 1 Reply Last reply Reply Quote 0
                • JonathanLeeJ
                  JonathanLee @JKnott
                  last edited by

                  @JKnott part of the 48 bit MAC address has vendor information you can use part of the 48 bit mac and find who made the device by way of online database.

                  Make sure to upvote

                  johnpozJ JKnottJ 2 Replies Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @JonathanLee
                    last edited by

                    @JonathanLee pretty sure kea dhcpv6 allows for reservation of ipv6 via mac vs duid.. If that will help you out.. at some point here that will prob make it to pfsense integration.

                    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 2.7.2, 24.11

                    JonathanLeeJ 1 Reply Last reply Reply Quote 1
                    • JonathanLeeJ
                      JonathanLee @johnpoz
                      last edited by

                      @johnpoz I made a feature request for it but

                      https://redmine.pfsense.org/issues/15632

                      Jim pingle closed it

                      Make sure to upvote

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

                        @JonathanLee its not going to do it for any IP out of the pool.. It would be for a reservation..

                        https://kb.isc.org/docs/what-are-host-reservations-how-to-use-them

                        hardware address is one of the options of the host-reservation-identifiers

                        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 2.7.2, 24.11

                        JonathanLeeJ 1 Reply Last reply Reply Quote 0
                        • JonathanLeeJ
                          JonathanLee @johnpoz
                          last edited by

                          @johnpoz maybe I should reopen it as a host reservation feature request

                          Make sure to upvote

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

                            @JonathanLee not even sure why you are putting in a feature request at this point.. I would wait til kea is out of preview.. I would think since it is a clearly defined option in kea, that it would most likely be available once they out of preview mode for kea.

                            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 2.7.2, 24.11

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

                              @JonathanLee

                              Yes, I've been aware of that for coming up on 30 years.

                              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...

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