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    Private Mac addresses in IOS14

    Scheduled Pinned Locked Moved General pfSense Questions
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    • NogBadTheBadN
      NogBadTheBad
      last edited by

      You can set don't use private MAC addresses for each SSID you join.

      Andy

      1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

      JKnottJ 1 Reply Last reply Reply Quote 1
      • B
        bcruze
        last edited by

        I’ll explain what happened after I updated a few of my devices on my network.

        I originally assigned a few devices by MAC address specific ip addresses. Created an alias, created a rule for those alias to go out a certain gateway. After updating my devices I didn’t realize this new feature was enabled so the original traffic path was not working. Since these are my devices I could turn that new feature off, and all was normal again

        2nd observation because a new MAC address was generated a new dhcp leased address was taken.. on bigger networks with a limited pool that can cause an issue

        Just sharing my experience after updating my devices 😁

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        • JKnottJ
          JKnott @NogBadTheBad
          last edited by

          @NogBadTheBad

          Also, there's no such thing as a "private" MAC. You either use whatever the hardware came with or, with some equipment, use a locally assigned MAC. Either way, it doesn't make any difference once you pass through a router.

          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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          • NogBadTheBadN
            NogBadTheBad @JKnott
            last edited by NogBadTheBad

            @JKnott said in Private Mac addresses in IOS14:

            @NogBadTheBad

            Also, there's no such thing as a "private" MAC. You either use whatever the hardware came with or, with some equipment, use a locally assigned MAC. Either way, it doesn't make any difference once you pass through a router.

            it’s generating a random MAC per SSID.

            A2:F3:9B & 76:9E:2F from the same device with Private Addresses enabled.

            Andy

            1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

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

              @NogBadTheBad

              Again, the MAC address is completely irrelevant beyond the first router. So, if you're running your own router, not even your ISP will see your phone's MAC address. The snooping must be done no later than that first router. It's definitely tinfoil hat time!

              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...

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

                While it is possible that use of a different mac (what apple is calling "private") could cause you issues on your local controls. Be it a captive portal, or dhcp reservations not working so you can filter or route specific IPs based upon that device always getting the same IP via its reservation.

                The privacy aspect of this is really meant for when you bounce around using different wifi networks. So for example you use the same mac at Starbucks and you do at McDonalds - from this it would be possible for "someone" to know that hey the same device was both at starbucks and mcdonalds.. While this mac doesn't really tell them who is person was - from info given to say access the captive portal.. It could allow for tracking of billy across multiple networks - if the operator/owners of these networks share information about what mac addresses are accessing their network.

                As mentioned a few times already - mac are only seen at the L2 you are directly connected to.

                For control and routing of these devices on your own local network, would suggest you disable use of these so called "private" mac on your own local networks. So that your dhcp assignments still work, and captive portals and or policy routing function how you want them too.

                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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                • NogBadTheBadN
                  NogBadTheBad @JKnott
                  last edited by

                  @JKnott said in Private Mac addresses in IOS14:

                  @NogBadTheBad

                  Again, the MAC address is completely irrelevant beyond the first router. So, if you're running your own router, not even your ISP will see your phone's MAC address. The snooping must be done no later than that first router. It's definitely tinfoil hat time!

                  Not sure why you keep saying this, what Apple term as private MAC addresses are really only designed to be used away from home.

                  It’s really only of use when you are using free wifi and don’t want your MAC address to be registered whenever you connect away from home

                  Andy

                  1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

                  1 Reply Last reply Reply Quote 2
                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Yeah, this could be painful initially when those devices send a different MAC but it's not random every time they connect back to the same SSID.

                    Android does this now too: https://source.android.com/devices/tech/connect/wifi-mac-randomization

                    Steve

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                    • JKnottJ
                      JKnott @stephenw10
                      last edited by

                      @stephenw10

                      I just checked my Pixel 2 with my guest SSID and see it does use a random MAC for new SSIDs. However, anything I had set up on previous phones uses device MAC. I hadn't even known about that setting.

                      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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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Ah that's good to know.

                        It was also unclear if it does this now by default on either OS but I think it does.

                        Steve

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                        • JKnottJ
                          JKnott @stephenw10
                          last edited by JKnott

                          @stephenw10

                          My Pixel 2 with Android 10 has it, but not my Asus tablet with Android 7. Random is default, except for previously configured connections. So, any that were inherited from my Nexus 5 use the device MAC.

                          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
                          • V
                            Vollans @stephenw10
                            last edited by

                            @stephenw10 said in Private Mac addresses in IOS14:

                            It was also unclear if it does this now by default on either OS but I think it does.

                            It certainly turned on by default on my iPad Pro and iPhone 11 Max.

                            NollipfSenseN 1 Reply Last reply Reply Quote 0
                            • NollipfSenseN
                              NollipfSense @Vollans
                              last edited by

                              @Vollans said in Private Mac addresses in IOS14:

                              @stephenw10 said in Private Mac addresses in IOS14:

                              It was also unclear if it does this now by default on either OS but I think it does.

                              It certainly turned on by default on my iPad Pro and iPhone 11 Max.

                              I upgraded last night just to see what's about ... seems like much to do about nothing even if turned on by default.

                              pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by

                                Yeah not sure who it would cause headache for - other than someone that doesn't under how dhcp reservations work..

                                So it turned it on for networks your phone had already been connected too?

                                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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                                • JKnottJ
                                  JKnott @johnpoz
                                  last edited by

                                  @johnpoz said in Private Mac addresses in IOS14:

                                  So it turned it on for networks your phone had already been connected too?

                                  My understanding is it picks a new random MAC when connecting to a new SSID. It shouldn't change when you connect again.

                                  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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                                  • V
                                    Vollans @johnpoz
                                    last edited by

                                    @johnpoz yes, my pre-existing learnt networks have it switched on automatically. For me, that's not a problem.

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                                    • DerelictD
                                      Derelict LAYER 8 Netgate
                                      last edited by

                                      Apple seems to have a pretty good POLA violation on their hands here, IMHO. Considering it uses the same MAC address every time it connects to the same network it shouldn't break things like Captive Portals or DHCP pools. But static mappings, etc will certainly break.

                                      The user should have at least been asked if they want new MAC addresses for existing networks, while the blank stares at the screen from the majority would be funny to montage.

                                      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
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by

                                        @Derelict said in Private Mac addresses in IOS14:

                                        The user should have at least been asked

                                        Yeah no shit ;) First thing I had to go and turn off on my 3 apple devices as I updated them to 14 the other day.. Not a peep from the thing that it was doing this..

                                        Why do these OS makers continue to treat their users like idiots.. The last sort of thing that was pissing me off is windows with its update to 2004.. Just saying your machine is not ready -- well why and the F not?? Clearly you know why its not updating, because your not letting it... But what is the specific reason.. So possible it can be corrected.

                                        Finally had to just do a freaking clean install.. Works fine..

                                        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

                                        DerelictD JKnottJ 2 Replies Last reply Reply Quote 0
                                        • DerelictD
                                          Derelict LAYER 8 Netgate @johnpoz
                                          last edited by

                                          @johnpoz said in Private Mac addresses in IOS14:

                                          Why do these OS makers continue to treat their users like idiots..

                                          🤔

                                          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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                                          • JKnottJ
                                            JKnott @johnpoz
                                            last edited by

                                            @johnpoz said in Private Mac addresses in IOS14:

                                            Why do these OS makers continue to treat their users like idiots..

                                            Maybe because they bought iPhones. 😉 <ducking>

                                            With Android, it appears to generate a random MAC when first connected to an SSID and then use it for all future connections.

                                            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...

                                            NogBadTheBadN 1 Reply Last reply Reply Quote 0
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