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    IPv6 EUI-64??

    Scheduled Pinned Locked Moved IPv6
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @JonathanLee
      last edited by johnpoz

      @JonathanLee I have no idea what your going on about.. Let your device get whatever IP it wants to get, its going to use a temp address to talk to stuff anyway.. Unless you have disabled that.

      With ipv6 you filter at the prefix level - who cares what the devices IP address is..

      The only time your going to need to know the clients IP address is if its serving something that you want to all other devices to get too.. So either set it static, or set it via dhcpv6..

      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

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

        @JonathanLee said in IPv6 EUI-64??:

        about 2 hours ago

        @johnpoz again a static IPv6 still requires the admin to use a client MAC address. Eui-64 just uses the mac as part of an IPv6 address. Any MAC address can be spoofed again eui-64 for home use it just makes it a bit easier to track stuff without hand inputting every static mapping. Is there anyway to enable eui64 in pfSense?

        What you do is start by blocking everything and then enabling only what you want. With SLAAC, a device will have 1 consistent address and up to 7 privacy addresses, where you get a new one every day. The privacy addresses are used for outgoing connections and you'd use the consistent one if you wanted to set up a server, etc..

        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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        • JonathanLeeJ
          JonathanLee @johnpoz
          last edited by JonathanLee

          @johnpoz this temp IP is new to me I haven’t used IPv6 much it is still weird to see 3 ip addresses for IPv6 on a device. Just to confirm pfSense can’t enable EUI-64 there is no option for it?

          Make sure to upvote

          JKnottJ patient0P 2 Replies Last reply Reply Quote 0
          • JKnottJ
            JKnott @JonathanLee
            last edited by

            @JonathanLee said in IPv6 EUI-64??:

            still weird to see 3 ip addresses for IPv6 on a device.

            Give it a week. You'll see 8 global address and 1 link local. 7 of those global addresses are temporary. You get a new one every day and the oldest falls off the list. For more fun, you can enable Unique Local addresses for another 8!

            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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            • patient0P
              patient0 @JonathanLee
              last edited by patient0

              @JonathanLee

              @JonathanLee said in IPv6 EUI-64??:

              pfSense can’t enable EUI-64

              I have not use it myself and therefore don't know the effect it got on pfSense but check this Reddit thread:

              https://www.reddit.com/r/freebsd/comments/1awv0jw/ipv6_privacy/

              Quote from the thread:

              Privacy extensions can be enabled with these sysctl tweaks.

              net.inet6.ip6.use_tempaddr=1
              net.inet6.ip6.prefer_tempaddr=1
              

              To make it persistent add it to your sysctl.conf

              Also add this to your rc.conf

              ipv6_privacy="YES"
              
              JonathanLeeJ 2 Replies Last reply Reply Quote 1
              • JonathanLeeJ
                JonathanLee @patient0
                last edited by JonathanLee

                @patient0 thank you that is what I am after. A way to activate that protocol Thank you. I would need to disable them on my needs thoe

                Make sure to upvote

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                • JKnottJ
                  JKnott @JonathanLee
                  last edited by

                  @JonathanLee said in IPv6 EUI-64??:

                  How do I enable IPv6 EUI-64 on my IPv6dhcp server?

                  I missed the EUI-64 part of the question earlier. EUI-64, like EUI-48 before it, is simply a MAC address. It's not something you enable. With IPv6, it's emulated by sticking FFFE in the middle of the 48 bit MAC and flipping the 7th bit.

                  Given that EUI 48 or 64 is determined by hardware, I don't see why you're worried about it. Here's some info about where EUI-48 & EUI-64 are used.

                  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 JonathanLee

                    @JKnott Yes I want to use it. I would like to utilize EUI-64/EUI-48

                    I want to expose my MAC address inside of the ipv6 address for local hosts. I want to see the MAC address of the host inside of every ipv6 address that is assigned from pfsense to the clients.

                    That is my ultimate goal.

                    net.inet6.ip6.use_tempaddr is set to 0 already however I am not seeing a mac addresses within the ipv6 addresses

                    "bit-reversed order, non-canonical form" So it might be in big-endian or little-endian. I might have them already displayed however to the average user that is something they would assume is incorrect.

                    Make sure to upvote

                    JKnottJ 1 Reply Last reply Reply Quote 0
                    • JonathanLeeJ
                      JonathanLee @patient0
                      last edited by JonathanLee

                      @patient0 said in IPv6 EUI-64??:

                      ipv6_privacy

                      They are all prebuilt system tunables and they have it auto disabled

                      RESOLVED:

                      To enable EUI-64

                      change system tunables

                      net.inet6.ip6.use_tempaddr=1
                      net.inet6.ip6.prefer_tempaddr=1
                      ipv6_privacy=YES
                      

                      check status IPV6 dhcp leases and specifically look at the DUID this will now reflect the MAC address of the host using the address. That is it. Mine are clear and match the MAC address now. Easy

                      "DUID (Device Unique Identifier) is a key part of the DHCPv6 protocol that helps to ensure that each client device on a network has a unique IP address. This prevents the possibility of duplicate IP assignments, which can lead to network issues such as routing loops and DNS conflicts."

                      Make sure to upvote

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                      • JKnottJ
                        JKnott @JonathanLee
                        last edited by

                        @JonathanLee said in IPv6 EUI-64??:

                        @JKnott Yes I want to use it. I would like to utilize EUI-64/EUI-48

                        On Ethernet, your MAC is EUI-48 and there's nothing you can do about it. If you want EUI-64, you'll have to run something like Firewire or Zigbee. As I mentioned, IPv6 emulates it by converting the EUI-48 by sticking FFFE in the middle. There is nothing else to do.

                        What's described above, in the system tunables, is enabling privacy addresses. With SLAAC, you normally get up to 7 of them anyway. Privacy addresses have a lifetime of 7 days and you get a new one every day.

                        Read the link above about EUI-64 and this:

                        A 64-bit interface identifier can be derived from the interface's 48-bit MAC address, although stable privacy addresses are now recommended as a default instead.[2] A MAC address 00-0C-29-0C-47-D5 is turned into a 64-bit EUI-64 by inserting FF-FE in the middle: 00-0C-29-FF-FE-0C-47-D5.[f]

                        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 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 2.8, 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 2.8, 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 2.8, 24.11

                                            JonathanLeeJ 1 Reply Last reply Reply Quote 0
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