19 ms·

macOS no longer allows changing wifi mac address

444 points by MilnerRoute 7y ago

chrisseaton 7y ago
How would you get allocated a new MAC address in order to do this?
- schoen 7y ago
  You normally would just pick a random one, and you have probability near 1/2⁴⁸ of colliding with each other device on your LAN.
  - joshvm 7y ago
    It may be more like one in 2^24. The first 24 bits are allocated for other things, so it depends how the address is randomised (eg if you keep the manufacturer bits). Though if you report a totally random address it probably will be closer to 2^48. https://www.ionos.co.uk/digitalguide/server/know-how/mac-address/ https://www.ionos.co.uk/digitalguide/server/know-how/mac-add...
    - zamadatix 7y ago
      You should really be setting the "Locally Administered" bit to 1 when generating random MACs. This combined with the unicast bit should give you 2^46 possibilities without the chance to collide with a globally assigned address at all. https://www.hellion.org.uk/cgi-bin/randmac.pl https://www.hellion.org.uk/cgi-bin/randmac.pl
    - AndyMcConachie 7y ago
      The lowest order bit of the first byte must be 0 for a station MAC. If it is 1 then it is a multicast MAC which can never be a source MAC. A MAC can also never be all zeros. So I think it works out to something like (2^47)-1. I'm probably forgetting some other specifics so it might even be lower than that. There's a bunch of incorrect information on the link in parent. A simple example is that 01:00:5e:00:00:01 is NOT a valid source MAC address.
- xnyan 7y ago
  It's never worked like that, you just provide an arbitrary address, Collisions are not really an issue because it's a manual thing done by a professional for one of any number of uncommon but legitimate reasons. Assuming its not a bug, to me this seems like yet another small but meaningful step in turning macOS from a general purpose OS to a consumer only OS with all the "most people don't want or need this" stuff taken out.
  - Jonnax 7y ago
    A "professional" doesn't do anything except randomise the address. Because a collision is extremely unlikely. Especially in a /24 which has 254 addresses max.
    - bowmessage 7y ago
      Or they spoof it for logging into WiFi portals
    - kryogen1c 7y ago
      What are you talking about? MACs are 48 bits, and the unique ID is 24 bits if you preserve your real OUI. This doesnt have anything to do with with an IPv4 address. Furthermore, "professionals" rarely randomize their IPv4 address; theres almost no value in it. The subset of people with some kind DHCP filtering but no NAC or DHCP enforcement is miniscule.
      - joosters 7y ago
        MAC addresses only have to be unique to your local network, they aren't used for wider inter-network routing.
      - mlyle 7y ago
        If a subnet has 254 machines, they are all made by the same vendor, and the last 3 bytes of the mac address are randomized for every one... There's (254*253)/2 combinations of machines. Each one has a probability of about 1/16777216 of a collision with true random numbers. The number of collisions you expect in this scenario is ~0.0038 over the network. With the wacky problems that happen on MAC collision, this is rare but still too common for routine use. But the chance of any issues, if now and then a few professionals randomize their address, is basically nil.
TazeTSchnitzel 7y ago
Apple do MAC address randomisation on iOS, right? Does this mean macOS doesn't do that, or that does but you can't turn it off?
- _bxg1 7y ago
  It seems more like Apple to strongarm people into something that's probably best for them - for security, privacy, etc. - than to place limits on their customers just to buddy up with [checks notes]...hotel chains. The removal of an option here could imply that they started randomizing the ones on macOS.
  - spsful 7y ago
    I'd like to see more testing done to see if that's actually happening. Since Apple has a very vocal stance on privacy, I would really hope that is the case.
    - _bxg1 7y ago
      Agreed.
  - cozzyd 7y ago
    That would break DHCP-assigned static ip's if there was no way to disable it, a crucial feature.
- stefan_ 7y ago
  As I understand it, the address randomisation is only for the probes to check if a configured network is present; once you are connected, it uses the real MAC address.
rkaregaran 7y ago
I experienced this a couple of months ago while trying to spoof a hotel room's captive portal. I was attempting to get a Chromecast to work, which isn't designed to operate with wifi connections behind captive portals. Very frustrating and no feedback from the OS that the commands I was running weren't actually doing what it said it was doing. This was on a latest gen MacBook Pro 15" running latest version at the time of MacOS.
- pfranz 7y ago
  I've done the exact same thing in order to get an AppleTV (that doesn't have a web browser) onto a hotel's wifi.
- sovnade 7y ago
  It won't help your chromecast, but the Roku streaming sticks work fine on Hotel wifi. You connect the roku to it, then connect your phone to the Roku's direct wifi and go through the portal on your phone. It's worked in every hotel I've been in perfectly.
- chmars 7y ago
  1/2 OT: The Apple Watch does not work with captive portals either. And since 4G does not work abroad, I can use my Apple Watch without my iPhone nearby only in my home country.
  - askmike 7y ago
    > And since 4G does not work abroad What do you mean? I can roam 4g just fine.
    - techsupporter 7y ago
      The mobile radio in the Apple Watch, at least according to Apple, does not work when you are outside of the region where the Watch was purchased. 4G works fine on the iPhone handset but the Watch won't independently connect to a local mobile network sans the iPhone. (For example: I bought my Watch in the U.S. While on vacation to Ireland, my iPhone connected to Vodafone IE without a problem. But my Watch showed "no cellular service" if it was out of range of my iPhone and a wifi network.)
ivanstegic 7y ago
All the more reason to buy a Lenovo and put Linux on it.
- lars_francke 7y ago
  If you do so don't get a T490 or if you do don't get an NVidia card. It'll destroy your battery life. The (Lenovo and others) forums have threads on these issue. For me idle time dropped from 11 to 3h.As someone else mentioned as well don't get the "best" WWAN Modem (850 something I believe ) as there are _no_ Linux drivers. In other news: anyone wants to buy a lightly used lenovo T490?
  - kart23 7y ago
    It wont destroy your battery life. I have a t480s with the nvidia card. You need to turn the card off when booting linux and just use the cpu for display. Research a bit about bumblebee and bbswitch.
    - tstrimple 7y ago
      Wait, how is "it won't destroy your battery life" somehow supported by "you need to turn off the card when booting linux". It sounds like you're saying it will destroy the battery life if it's not turned off. Did I misread that?
      - kart23 7y ago
        Sorry, I should have been more clear. Do you have a reason to use the graphics card on battery in Linux? Most people don't, so turning it off makes sense. You didn't misread it.
        lars_francke 7y ago
        The problem is that on the T490 you can't turn it off. It never enters power saving states on Linux and there's no UEFI option to disable it. There's plenty of threads on the Lenovo forums about this.
jajajajaj 7y ago
Just when I was about to reconsider buying a MacBook if they upgrade the keyboard on the next version.
- ivanstegic 7y ago
  Don’t waste your time, the Lenovo X1 Carbons are comparable (if not better) and the keyboard is amazing! Consider it.
  - sitkack 7y ago
    Are the trackpads on par? The heuristics in the OSX trackpad driver are excellent, as is the hardware.
    - ivanstegic 7y ago
      I would say almost on par. They are certainly not the same.
    - bluedino 7y ago
      No.
    - mmastrac 7y ago
      OSX used be on top for trackpad drivers, but my 2019 fails pretty miserable at palm rejection. Disappointing how far quality has fallen.
      - megaremote 7y ago
        This is unheralded rubbish.
        mmastrac 7y ago
        If you have a more substantive comment, I'd be happy to discuss but this is not very constructive.
simonklitj 7y ago
Seems to be a hardware related thing, as WiFiSpoof (https://wifispoof.com https://wifispoof.com) lists 2018/2019 devices as the ones not supported, and not a specific macOS version.
- miles 7y ago
  In fact, they explicitly recommend using Mojave on that page: "10.11 or better (Mojave recommended)"
- Dunedan 7y ago
  That smells like it's related to the T2 chip.
discobean 7y ago
I recently tried this and was able to change the address of only the last few characters, it wouldn't let me change the address entirely. I just suspected it just had a check on the first bytes of the address to be sure it was a valid Apple ethernet adapter.
- MiroF 7y ago
  This is still unpatched on my system... hope not too many Apple engineers are browsing these forums If Apple renders it impossible to change my address at all, I definitely won’t be purchasing their computers any more.
  - nodesocket 7y ago
    Because you can’t change the MAC you are going to completely abandon Apple? This seems a bit ridiculous. I refuse to run Windows and Linux from a GUI/workstation/productivity standpoint doesn’t work for me.
    - rburhum 7y ago
      For some privacy features are more important than for others
    - novok 7y ago
      It's probably more of a 'last straw on the camel's back', not the specific situation.
    - dmitryminkovsky 7y ago
      Changing your MAC is critical to privacy.
  - fouc 7y ago
    It's probably easier to compensate with a portable router that you can configure instead. Unfortunately
- alexis_fr 7y ago
mahesh_rm 7y ago
I count heavily on this feature when working with my 2015 macbook pro from public WiFi. If it's a hardware limit, it would be a deal breaker for a MacBook update. Anybody knowledgeable of the issue can pitch in on weather it is a deliberate choice or the collateral effect of non yet supported hardware?
gruez 7y ago
This is disappointing from a privacy oriented company. Windows had mac address randomization for a few years now. It even supports randomizing on a per-network basis and automatic daily rotations. https://www.tenforums.com/attachments/tutorials/110342d1485974035t-turn-off-random-hardware-mac-addresses-wi-fi-windows-10-a-wi-fi_random_hardware_addresses-3.png https://www.tenforums.com/attachments/tutorials/110342d14859...
- sarah180 7y ago
  Even on Windows it depends on your hardware. I have two Windows laptops. One supports MAC randomization. The other won't allow it because the hardware reports that the MAC address is locked.
techsupporter 7y ago
This does look like a change on more recent hardware. I just tried the script that the parent linked from Stack Overflow[0] on my 2017 MacBook 12" running the latest Catalina public beta and it does work. I can change my MAC and my laptop gets a new IPv4 address from DHCP. Edited to add: I also just tried this on my 2018 Mac Mini (also running latest Catalina public beta) and it also worked... Different wireless adapter from the MacBook Pro line maybe? 0 - https://stackoverflow.com/questions/52421789/cant-spoof-mac-address-in-a-macbook https://stackoverflow.com/questions/52421789/cant-spoof-mac-...
bob1029 7y ago
I am still having a really hard time finding a reason to upgrade my late-2013 MBP (which I am currently typing this on) to any of their newer hardware. Every generation that came out was "meh, 5% more perf, 10% more bullshit compromise". At this point, I am looking forward to October 22nd. I will be checking out the new surface laptops as a replacement. I think I was already sold when the presenter removed the top cover on stage. I really enjoy the UX that macOS affords, but Apple is simultaneously so abusive to developers and tinkerers. It's hard to reason with and I just feel like I am done with them at this point. I'll get a new battery installed on this machine and keep it around as an emergency iOS app build agent (for as long as latest Xcode->macOS->my hardware are supported, that is). Ideally, we move all of our client's B2B apps onto UWP/Android/PWA so I don't even have to maintain a build path to the hellhole that is iOS applications. My life as a developer could just consist of a Microsoft/Android stack and that would be so wonderful. I'd never have to leave visual studio again.
- ksec 7y ago
  MacBook Air Retina, We now have many reports of Retina MacBook Air's CPU dying. And it isn't even out for long, and most suspect it has to do with its new cooling method. MacBook Pro, while we all know the Keyboard sucks, and Touch Bar is either a love it or hate it addition, I am glad there are more people voicing the big trackpad is simply a bad design. It increase false positives which is very annoying to some people. Basically the I am looking at the whole MacBook Lineup and it seems everything is step backward. I surely hope the rumoured new MacBook Pro coming this October will fix all of these issues.
  - sascha_sl 7y ago
    Are you kidding, the trackpad is the main reason I wouldn't want a different device, and the palm rejection is really good too.
    - Tsiklon 7y ago
      I think the parent commenter is referring to the enlarged trackpads present on all thunderbolt 3 MacBooks, as compared with the smaller trackpad on the previous models.
kilroy123 7y ago
I constantly have to do this when connecting to public WiFis around the world, which limits usage. I'll just change the Mac address and I'm able to continue using the WiFi.
ConcernedCoder 7y ago
Fixed in Catalina @ 10.15 ?https://github.com/feross/SpoofMAC/issues/87#issuecomment-528147607 https://github.com/feross/SpoofMAC/issues/87#issuecomment-52...
- simonklitj 7y ago
  Currently on latest Catalina beta build. The command does nothing for me. Doesn't throw an error, but no address change either. Might add I have 2019 MBP.
  - dillonmckay 7y ago
    When is the Catalina public release date?
    - nvrspyx 7y ago
      There’s isn’t one. It’s just “Coming in October”. But, the GM build was recently pushed to beta, so probably pretty soon.
      - BigJ1211 7y ago
        It's generally about a week after the GM release, so you should expect it pretty soon. It was released last friday, so it might be end of this week early next week.
  - jcoletti 7y ago
    Note that you will still see the original hardware address in System Prefs > Network > Wi-Fi > Advanced, but ifconfig shows the changed MAC, which is indeed the one that is broadcasted
- mehrdada 7y ago
  This. My 2018 MBP has issues with Mojave but Catalina works fine
deleted 7y ago
[deleted]
isostatic 7y ago
Macs are no longer suitable for general computing
DeMaob 7y ago
You can remove those by using the poweshell
glerk 7y ago
According to this: https://github.com/feross/SpoofMAC/issues/87#issuecomment-528147607 https://github.com/feross/SpoofMAC/issues/87#issuecomment-52... the issue will be resolved in the next Mac OS version (10.15 Catalina)
nixgeek 7y ago
I don’t think this is down to macOS version, it seems related to the vintage of the hardware. I have a Late 2016 15” which allows me to change the MAC address, and anything 2018+ does not seem to allow it. Both the 2018 and 2019 model return zero when you type “ifconfig” commands to change the hardware address, but the command has no effect. Have tried this on Mojave and Catalina.
yakshaving_jgt 7y ago
I panicked for a moment, since I travel a lot and changing my MAC address is the only way to circumvent draconian limited WiFi rules. Glad to see this is only temporary, and it'll be fixed before I end up buying a new machine. Here's how I get around free WiFi limitations while travelling: https://jezenthomas.com/free-internet-on-trains/ https://jezenthomas.com/free-internet-on-trains/
effnorwood 7y ago
Know why? Apple is the worst privacy offender and you’re their product.
jen_h 7y ago
They're kind of hurting their own product adoption here: Apple TV doesn't support the use of "gated" wifi connections (and that's on top of ensuring fewer people use Macs for pentesting/security stuff). If I couldn't spoof my mac address, I couldn't use Apple TV when traveling -- you have to set your computer's MAC to the Apple TV mac, connect to wifi, log in, switch back, then turn on the Apple TV. And for most hotels/gated wifi hotspots, you have to do this every. single. day. Luckily I use Ubuntu as my primary, but still... Here's to hoping they rethink this and add a feature to allow wifi login pages on AppleTV...
dopu 7y ago
Unrelated, but the MacRumors thread that's linked to has someone posting about neighbors harassing them by doing things such as "moving my cursor all over the place and speeding up the temperature, causing the fan" and that their "neighbors also learned to slow my internet (ATT DSL) or to disconnect it." [0] Hence their need change their MAC address. They're now in the process of collecting evidence, and post: "This legal evidence will benefit many, as they boast of being Freemasons, and this being part of their "craft" and their "process". Therefore, when I go public in legal proceeds about their "craft" and "process", while actually forcing those individuals which I have substantial evidence on to appear for the courtroom cameras, the rest of humanity they plague will see the low caliper, socially outcast, inadequates they are. No one need fear them. It's fear they try to attain, and before I'm finished, no one on earth ever will." Amazing. [0]: https://forums.macrumors.com/threads/change-mac-address.2154569/#post-27329950 https://forums.macrumors.com/threads/change-mac-address.2154...
- diminoten 7y ago
  This sounds like a CO2 leak or someone not taking their medication.
  - pfarnsworth 7y ago
    CO not CO2
    - diminoten 7y ago
      Good point!
- mruts 7y ago
  “ Yes, there are multiple harassers which then could slow my connection. Within minutes after shortening my wifi range, there were verbal complaints like - "I hate you". Bluetooth may well be the way for the talking, but of course my computer shows no blue tooth connection. I did run network software and got their computer IP addresses (I think that's the correct term). That's how I kicked them off the router, individually, after shortening the wifi range. But, one keeps changing the address, that's why I started this thread inquiry. Thought if I did the same, it would be harder to get on mine” Oh man. What is this person talking about?
userbinator 7y ago
There are others here who say this is a bug, not a feature, and I agree; and having looked through the open-source code that Apple releases, I have a reasonable guess of how this happened. Apple seems to have an internal developer culture that basically does not value backwards-compatibility nor stability, and instead really loves rewriting huge pieces of code all the time. If you look at the OSS that it releases, you'll see interfaces between the various components change greatly between versions and lots of other churn. There are many places which look unimplemented, with only stub functions present. With such a situation, it's not hard to envision how a simple "change the MAC address" function could've gotten left out of some piece during a rewrite, because it otherwise does not affect basic functionality. I really recommend downloading the OSS from Apple and inspecting it; the pieces it copied from BSDs etc. are relatively stable, but the amount of churn in other pieces is surprising to see.
- oneplane 7y ago
  I'm not sure about the internal culture, but externally they seem to stress the importance of only using public published interfaces and frameworks as API & ABI layers and not touching anything else as they won't guarantee any stability in private internals. (per their docs iirc)
  - LeoNatan25 7y ago
    Even with the so-called "public" APIs, the way Apple operates, there is no guarantee of any stability, as most iOS developers know. AppKit is much more stable than UIKit, but still nowhere near the stability that companies like Microsoft provide (including changing the name of a product—Windows 9->10—so that existing software does not break!). If you are using features of the frameworks that are outside of the "happy path" for that year's keynote announcements, you can expect terrible bugs on a yearly basis. These bugs happen for the exact same reasons as stated in the GP.
    - oneplane 7y ago
      But doesn't that go for anything? Take android where you need to account not only for all the cases of versions but also for every differentiated version from every brand and device, or if you build for things like silverlight which gets killed with no replacement. There are always things changing and unless you are on the same path as the vendor you're gonna get screwed. It's always been like that.
nickthemagicman 7y ago
What about via bash and ifconfig? Is this just a GUI thing?
deleted 7y ago
[deleted]
clubm8 7y ago
I had not tried in a long time. They have for a long time not allowed you to put airport into monitor mode easily, so I always just bought a USB wifi antenna for any wireless penetration testing. I'm surprised by this thought... is it not changable at all or just by the user? I know in iOS they had a feature to randomize the mac when searching out networks to increase privacy...
anonthrowaway28 7y ago
Running a hackintosh on 10.14.6 (18G103), works fine: $ ifconfig en1 ether en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 ether aa:bb:cc:dd:ee:ff It maybe related to wifi drivers. Index Refs Address Size Wired Name (Version) UUID <Linked Against> 37 10 0xffffff7f83b0e000 0x22000 0x22000 as.vit9696.Lilu (1.3.4) 7C0B7376-83CF-32DA-9C49-7052141EC730 <8 6 5 3 2 1> 38 0 0xffffff7f83b30000 0x5000 0x5000 org.vanilla.driver.CPUFriend (1.1.6) FFAD6CD3-E28F-3741-BE12-E44720F45CA6 <37 12 8 6 5 3 2 1> 39 0 0xffffff7f83b35000 0x4000 0x4000 com.rehabman.driver.USBInjectAll (0.7.1) 88901B62-E4A2-3374-A33C-873C8BC29F9C <13 12 5 3> 40 0 0xffffff7f83b3a000 0x3000 0x3000 as.lvs1974.BT4LEContiunityFixup (1.1.2) 1B490F7D-CD49-30AD-944A-553D0D99692C <37 8 6 5 3 2 1> 41 0 0xffffff7f83b3d000 0x4000 0x4000 com.sicreative.VoltageShift (1.1) 0FA3C2F1-BEA1-3AAF-AA39-3ED26996F2C1 <5 3> 42 2 0xffffff7f83b44000 0x11000 0x11000 as.vit9696.VirtualSMC (1.0.2) E9475ED7-4AB2-3DDE-B20B-614B06DAE65B <37 12 8 6 5 3 2 1> 44 0 0xffffff7f83b55000 0xa000 0xa000 ru.usrsse2.SMCBatteryManager (1) E0542A67-D72C-3FD4-A142-40B586E9CE50 <43 42 37 12 8 6 5 3 2 1> 45 0 0xffffff7f83b5f000 0x63000 0x63000 as.vit9696.WhateverGreen (1.2.7) 122F635A-DC40-3DF0-98AF-8505A83221C0 <37 13 8 6 5 3 2 1> 46 0 0xffffff7f83bc2000 0x102000 0x102000 as.vit9696.AppleALC (1.3.6) 3E1A3DF6-9D93-3DD0-96A0-9FBA5791D7D7 <37 13 8 6 5 3 2 1> 47 0 0xffffff7f83cc4000 0x6000 0x6000 as.lvs1974.AirportBrcmFixup (1.1.9) 6AE31546-1F21-303F-A51E-A34753C9905E <37 16 13 8 6 5 3 2 1> 48 0 0xffffff7f83cca000 0x3000 0x3000 xyz.racermaster.NoTouchID (1.0.1) 85F586AC-B564-304A-BCC0-55681EF86F91 <37 8 6 5 3 2 1> 49 0 0xffffff7f83ccd000 0x5000 0x5000 as.lvs1974.HibernationFixup (1.2.4) 8CA34F1A-5611-30B3-8224-53F093BF5FAA <37 8 6 5 3 2 1> 50 0 0xffffff7f83cd2000 0x5000 0x5000 as.vit9696.SMCProcessor (1.0.2) BB591E66-6993-39BB-88D9-D0936B92E036 <42 37 12 8 6 5 3 2 1> 67 2 0xffffff7f83cd7000 0xb000 0xb000 org.rehabman.voodoo.driver.PS2Controller (1.9.2) 53E0B467-6CA6-3CD1-A450-6A39D767DA8C <12 8 6 5 3 1> 81 0 0xffffff7f83ce2000 0x14000 0x14000 com.insanelymac.IntelMausiEthernet (2.5.0d0) D59B3731-D7AE-3CBA-A10F-4AB0C54AC05A <16 13 6 5 3 1> 88 0 0xffffff7f83cf6000 0xc000 0xc000 org.rehabman.voodoo.driver.PS2Trackpad (1.9.2) 1E85D11A-A05E-3FC3-AC6D-D28B7563B956 <67 57 18 8 7 6 5 3 1> 89 0 0xffffff7f83d02000 0x6000 0x6000 org.rehabman.voodoo.driver.PS2Keyboard (1.9.2) B974470A-CEE4-358B-B605-A09DFACEE4F4 <67 57 18 8 7 6 5 3 1> 99 1 0xffffff7f83d0c000 0x254000 0x254000 com.no-one.BrcmFirmwareStore (2.2.10) 4ED64118-8732-329E-A136-719F5CB78987 <6 5 3> 100 0 0xffffff7f83f60000 0x6000 0x6000 com.no-one.BrcmPatchRAM2 (2.2.10) B31288AE-941C-3064-8E7D-C00266BC302A <99 23 6 5 3 1>
huxflux 7y ago
This is one of the reasons I left macOS (and Apple).
Aissen 7y ago
Waiting a year for a driver fix for such a basic feature on widely used hardware, it makes Linux driver woes feel like a walk in the park.
fulldecent2 7y ago
Here is a legitimate practical use of editing your MAC: https://fulldecent.blogspot.com/2013/12/how-to-connect-your-roku-to-xfinitywifi.html https://fulldecent.blogspot.com/2013/12/how-to-connect-your-...

444 points by MilnerRoute 7y ago

chrisseaton 7y ago

How would you get allocated a new MAC address in order to do this?

schoen 7y ago
You normally would just pick a random one, and you have probability near 1/2⁴⁸ of colliding with each other device on your LAN.
- joshvm 7y ago
  It may be more like one in 2^24. The first 24 bits are allocated for other things, so it depends how the address is randomised (eg if you keep the manufacturer bits). Though if you report a totally random address it probably will be closer to 2^48. https://www.ionos.co.uk/digitalguide/server/know-how/mac-address/ https://www.ionos.co.uk/digitalguide/server/know-how/mac-add...
  - zamadatix 7y ago
    You should really be setting the "Locally Administered" bit to 1 when generating random MACs. This combined with the unicast bit should give you 2^46 possibilities without the chance to collide with a globally assigned address at all. https://www.hellion.org.uk/cgi-bin/randmac.pl https://www.hellion.org.uk/cgi-bin/randmac.pl
  - AndyMcConachie 7y ago
    The lowest order bit of the first byte must be 0 for a station MAC. If it is 1 then it is a multicast MAC which can never be a source MAC. A MAC can also never be all zeros. So I think it works out to something like (2^47)-1. I'm probably forgetting some other specifics so it might even be lower than that. There's a bunch of incorrect information on the link in parent. A simple example is that 01:00:5e:00:00:01 is NOT a valid source MAC address.
xnyan 7y ago
It's never worked like that, you just provide an arbitrary address, Collisions are not really an issue because it's a manual thing done by a professional for one of any number of uncommon but legitimate reasons. Assuming its not a bug, to me this seems like yet another small but meaningful step in turning macOS from a general purpose OS to a consumer only OS with all the "most people don't want or need this" stuff taken out.
- Jonnax 7y ago
  A "professional" doesn't do anything except randomise the address. Because a collision is extremely unlikely. Especially in a /24 which has 254 addresses max.
  - bowmessage 7y ago
    Or they spoof it for logging into WiFi portals
  - kryogen1c 7y ago
    What are you talking about? MACs are 48 bits, and the unique ID is 24 bits if you preserve your real OUI. This doesnt have anything to do with with an IPv4 address. Furthermore, "professionals" rarely randomize their IPv4 address; theres almost no value in it. The subset of people with some kind DHCP filtering but no NAC or DHCP enforcement is miniscule.
    - joosters 7y ago
      MAC addresses only have to be unique to your local network, they aren't used for wider inter-network routing.
    - mlyle 7y ago
      If a subnet has 254 machines, they are all made by the same vendor, and the last 3 bytes of the mac address are randomized for every one... There's (254*253)/2 combinations of machines. Each one has a probability of about 1/16777216 of a collision with true random numbers. The number of collisions you expect in this scenario is ~0.0038 over the network. With the wacky problems that happen on MAC collision, this is rare but still too common for routine use. But the chance of any issues, if now and then a few professionals randomize their address, is basically nil.

TazeTSchnitzel 7y ago

Apple do MAC address randomisation on iOS, right? Does this mean macOS doesn't do that, or that does but you can't turn it off?

_bxg1 7y ago
It seems more like Apple to strongarm people into something that's probably best for them - for security, privacy, etc. - than to place limits on their customers just to buddy up with [checks notes]...hotel chains. The removal of an option here could imply that they started randomizing the ones on macOS.
- spsful 7y ago
  I'd like to see more testing done to see if that's actually happening. Since Apple has a very vocal stance on privacy, I would really hope that is the case.
  - _bxg1 7y ago
    Agreed.
- cozzyd 7y ago
  That would break DHCP-assigned static ip's if there was no way to disable it, a crucial feature.
stefan_ 7y ago
As I understand it, the address randomisation is only for the probes to check if a configured network is present; once you are connected, it uses the real MAC address.

rkaregaran 7y ago

I experienced this a couple of months ago while trying to spoof a hotel room's captive portal. I was attempting to get a Chromecast to work, which isn't designed to operate with wifi connections behind captive portals. Very frustrating and no feedback from the OS that the commands I was running weren't actually doing what it said it was doing. This was on a latest gen MacBook Pro 15" running latest version at the time of MacOS.

pfranz 7y ago
I've done the exact same thing in order to get an AppleTV (that doesn't have a web browser) onto a hotel's wifi.
sovnade 7y ago
It won't help your chromecast, but the Roku streaming sticks work fine on Hotel wifi. You connect the roku to it, then connect your phone to the Roku's direct wifi and go through the portal on your phone. It's worked in every hotel I've been in perfectly.
chmars 7y ago
1/2 OT: The Apple Watch does not work with captive portals either. And since 4G does not work abroad, I can use my Apple Watch without my iPhone nearby only in my home country.
- askmike 7y ago
  > And since 4G does not work abroad What do you mean? I can roam 4g just fine.
  - techsupporter 7y ago
    The mobile radio in the Apple Watch, at least according to Apple, does not work when you are outside of the region where the Watch was purchased. 4G works fine on the iPhone handset but the Watch won't independently connect to a local mobile network sans the iPhone. (For example: I bought my Watch in the U.S. While on vacation to Ireland, my iPhone connected to Vodafone IE without a problem. But my Watch showed "no cellular service" if it was out of range of my iPhone and a wifi network.)

ivanstegic 7y ago

All the more reason to buy a Lenovo and put Linux on it.

lars_francke 7y ago
If you do so don't get a T490 or if you do don't get an NVidia card. It'll destroy your battery life. The (Lenovo and others) forums have threads on these issue. For me idle time dropped from 11 to 3h.As someone else mentioned as well don't get the "best" WWAN Modem (850 something I believe ) as there are _no_ Linux drivers. In other news: anyone wants to buy a lightly used lenovo T490?
- kart23 7y ago
  It wont destroy your battery life. I have a t480s with the nvidia card. You need to turn the card off when booting linux and just use the cpu for display. Research a bit about bumblebee and bbswitch.
  - tstrimple 7y ago
    Wait, how is "it won't destroy your battery life" somehow supported by "you need to turn off the card when booting linux". It sounds like you're saying it will destroy the battery life if it's not turned off. Did I misread that?
    - kart23 7y ago
      Sorry, I should have been more clear. Do you have a reason to use the graphics card on battery in Linux? Most people don't, so turning it off makes sense. You didn't misread it.
      - lars_francke 7y ago
        The problem is that on the T490 you can't turn it off. It never enters power saving states on Linux and there's no UEFI option to disable it. There's plenty of threads on the Lenovo forums about this.

jajajajaj 7y ago

Just when I was about to reconsider buying a MacBook if they upgrade the keyboard on the next version.

ivanstegic 7y ago
Don’t waste your time, the Lenovo X1 Carbons are comparable (if not better) and the keyboard is amazing! Consider it.
- sitkack 7y ago
  Are the trackpads on par? The heuristics in the OSX trackpad driver are excellent, as is the hardware.
  - ivanstegic 7y ago
    I would say almost on par. They are certainly not the same.
  - bluedino 7y ago
    No.
  - mmastrac 7y ago
    OSX used be on top for trackpad drivers, but my 2019 fails pretty miserable at palm rejection. Disappointing how far quality has fallen.
    - megaremote 7y ago
      This is unheralded rubbish.
      - mmastrac 7y ago
        If you have a more substantive comment, I'd be happy to discuss but this is not very constructive.

simonklitj 7y ago

Seems to be a hardware related thing, as WiFiSpoof (https://wifispoof.com https://wifispoof.com) lists 2018/2019 devices as the ones not supported, and not a specific macOS version.

miles 7y ago
In fact, they explicitly recommend using Mojave on that page: "10.11 or better (Mojave recommended)"
Dunedan 7y ago
That smells like it's related to the T2 chip.

discobean 7y ago

I recently tried this and was able to change the address of only the last few characters, it wouldn't let me change the address entirely. I just suspected it just had a check on the first bytes of the address to be sure it was a valid Apple ethernet adapter.

MiroF 7y ago
This is still unpatched on my system... hope not too many Apple engineers are browsing these forums If Apple renders it impossible to change my address at all, I definitely won’t be purchasing their computers any more.
- nodesocket 7y ago
  Because you can’t change the MAC you are going to completely abandon Apple? This seems a bit ridiculous. I refuse to run Windows and Linux from a GUI/workstation/productivity standpoint doesn’t work for me.
  - rburhum 7y ago
    For some privacy features are more important than for others
  - novok 7y ago
    It's probably more of a 'last straw on the camel's back', not the specific situation.
  - dmitryminkovsky 7y ago
    Changing your MAC is critical to privacy.
- fouc 7y ago
  It's probably easier to compensate with a portable router that you can configure instead. Unfortunately
alexis_fr 7y ago

mahesh_rm 7y ago

I count heavily on this feature when working with my 2015 macbook pro from public WiFi. If it's a hardware limit, it would be a deal breaker for a MacBook update. Anybody knowledgeable of the issue can pitch in on weather it is a deliberate choice or the collateral effect of non yet supported hardware?

gruez 7y ago

This is disappointing from a privacy oriented company. Windows had mac address randomization for a few years now. It even supports randomizing on a per-network basis and automatic daily rotations. https://www.tenforums.com/attachments/tutorials/110342d1485974035t-turn-off-random-hardware-mac-addresses-wi-fi-windows-10-a-wi-fi_random_hardware_addresses-3.png https://www.tenforums.com/attachments/tutorials/110342d14859...

sarah180 7y ago
Even on Windows it depends on your hardware. I have two Windows laptops. One supports MAC randomization. The other won't allow it because the hardware reports that the MAC address is locked.

techsupporter 7y ago

This does look like a change on more recent hardware. I just tried the script that the parent linked from Stack Overflow[0] on my 2017 MacBook 12" running the latest Catalina public beta and it does work. I can change my MAC and my laptop gets a new IPv4 address from DHCP. Edited to add: I also just tried this on my 2018 Mac Mini (also running latest Catalina public beta) and it also worked... Different wireless adapter from the MacBook Pro line maybe? 0 - https://stackoverflow.com/questions/52421789/cant-spoof-mac-address-in-a-macbook https://stackoverflow.com/questions/52421789/cant-spoof-mac-...

bob1029 7y ago

I am still having a really hard time finding a reason to upgrade my late-2013 MBP (which I am currently typing this on) to any of their newer hardware. Every generation that came out was "meh, 5% more perf, 10% more bullshit compromise". At this point, I am looking forward to October 22nd. I will be checking out the new surface laptops as a replacement. I think I was already sold when the presenter removed the top cover on stage. I really enjoy the UX that macOS affords, but Apple is simultaneously so abusive to developers and tinkerers. It's hard to reason with and I just feel like I am done with them at this point. I'll get a new battery installed on this machine and keep it around as an emergency iOS app build agent (for as long as latest Xcode->macOS->my hardware are supported, that is). Ideally, we move all of our client's B2B apps onto UWP/Android/PWA so I don't even have to maintain a build path to the hellhole that is iOS applications. My life as a developer could just consist of a Microsoft/Android stack and that would be so wonderful. I'd never have to leave visual studio again.

ksec 7y ago
MacBook Air Retina, We now have many reports of Retina MacBook Air's CPU dying. And it isn't even out for long, and most suspect it has to do with its new cooling method. MacBook Pro, while we all know the Keyboard sucks, and Touch Bar is either a love it or hate it addition, I am glad there are more people voicing the big trackpad is simply a bad design. It increase false positives which is very annoying to some people. Basically the I am looking at the whole MacBook Lineup and it seems everything is step backward. I surely hope the rumoured new MacBook Pro coming this October will fix all of these issues.
- sascha_sl 7y ago
  Are you kidding, the trackpad is the main reason I wouldn't want a different device, and the palm rejection is really good too.
  - Tsiklon 7y ago
    I think the parent commenter is referring to the enlarged trackpads present on all thunderbolt 3 MacBooks, as compared with the smaller trackpad on the previous models.

kilroy123 7y ago

I constantly have to do this when connecting to public WiFis around the world, which limits usage. I'll just change the Mac address and I'm able to continue using the WiFi.

ConcernedCoder 7y ago

Fixed in Catalina @ 10.15 ?https://github.com/feross/SpoofMAC/issues/87#issuecomment-528147607 https://github.com/feross/SpoofMAC/issues/87#issuecomment-52...

simonklitj 7y ago
Currently on latest Catalina beta build. The command does nothing for me. Doesn't throw an error, but no address change either. Might add I have 2019 MBP.
- dillonmckay 7y ago
  When is the Catalina public release date?
  - nvrspyx 7y ago
    There’s isn’t one. It’s just “Coming in October”. But, the GM build was recently pushed to beta, so probably pretty soon.
    - BigJ1211 7y ago
      It's generally about a week after the GM release, so you should expect it pretty soon. It was released last friday, so it might be end of this week early next week.
- jcoletti 7y ago
  Note that you will still see the original hardware address in System Prefs > Network > Wi-Fi > Advanced, but ifconfig shows the changed MAC, which is indeed the one that is broadcasted
mehrdada 7y ago
This. My 2018 MBP has issues with Mojave but Catalina works fine

deleted 7y ago

[deleted]

isostatic 7y ago

Macs are no longer suitable for general computing

DeMaob 7y ago

You can remove those by using the poweshell

glerk 7y ago

According to this: https://github.com/feross/SpoofMAC/issues/87#issuecomment-528147607 https://github.com/feross/SpoofMAC/issues/87#issuecomment-52... the issue will be resolved in the next Mac OS version (10.15 Catalina)

nixgeek 7y ago

I don’t think this is down to macOS version, it seems related to the vintage of the hardware. I have a Late 2016 15” which allows me to change the MAC address, and anything 2018+ does not seem to allow it. Both the 2018 and 2019 model return zero when you type “ifconfig” commands to change the hardware address, but the command has no effect. Have tried this on Mojave and Catalina.

yakshaving_jgt 7y ago

I panicked for a moment, since I travel a lot and changing my MAC address is the only way to circumvent draconian limited WiFi rules. Glad to see this is only temporary, and it'll be fixed before I end up buying a new machine. Here's how I get around free WiFi limitations while travelling: https://jezenthomas.com/free-internet-on-trains/ https://jezenthomas.com/free-internet-on-trains/

effnorwood 7y ago

Know why? Apple is the worst privacy offender and you’re their product.

jen_h 7y ago

They're kind of hurting their own product adoption here: Apple TV doesn't support the use of "gated" wifi connections (and that's on top of ensuring fewer people use Macs for pentesting/security stuff). If I couldn't spoof my mac address, I couldn't use Apple TV when traveling -- you have to set your computer's MAC to the Apple TV mac, connect to wifi, log in, switch back, then turn on the Apple TV. And for most hotels/gated wifi hotspots, you have to do this every. single. day. Luckily I use Ubuntu as my primary, but still... Here's to hoping they rethink this and add a feature to allow wifi login pages on AppleTV...

dopu 7y ago

Unrelated, but the MacRumors thread that's linked to has someone posting about neighbors harassing them by doing things such as "moving my cursor all over the place and speeding up the temperature, causing the fan" and that their "neighbors also learned to slow my internet (ATT DSL) or to disconnect it." [0] Hence their need change their MAC address. They're now in the process of collecting evidence, and post: "This legal evidence will benefit many, as they boast of being Freemasons, and this being part of their "craft" and their "process". Therefore, when I go public in legal proceeds about their "craft" and "process", while actually forcing those individuals which I have substantial evidence on to appear for the courtroom cameras, the rest of humanity they plague will see the low caliper, socially outcast, inadequates they are. No one need fear them. It's fear they try to attain, and before I'm finished, no one on earth ever will." Amazing. [0]: https://forums.macrumors.com/threads/change-mac-address.2154569/#post-27329950 https://forums.macrumors.com/threads/change-mac-address.2154...

diminoten 7y ago
This sounds like a CO2 leak or someone not taking their medication.
- pfarnsworth 7y ago
  CO not CO2
  - diminoten 7y ago
    Good point!
mruts 7y ago
“ Yes, there are multiple harassers which then could slow my connection. Within minutes after shortening my wifi range, there were verbal complaints like - "I hate you". Bluetooth may well be the way for the talking, but of course my computer shows no blue tooth connection. I did run network software and got their computer IP addresses (I think that's the correct term). That's how I kicked them off the router, individually, after shortening the wifi range. But, one keeps changing the address, that's why I started this thread inquiry. Thought if I did the same, it would be harder to get on mine” Oh man. What is this person talking about?

userbinator 7y ago

There are others here who say this is a bug, not a feature, and I agree; and having looked through the open-source code that Apple releases, I have a reasonable guess of how this happened. Apple seems to have an internal developer culture that basically does not value backwards-compatibility nor stability, and instead really loves rewriting huge pieces of code all the time. If you look at the OSS that it releases, you'll see interfaces between the various components change greatly between versions and lots of other churn. There are many places which look unimplemented, with only stub functions present. With such a situation, it's not hard to envision how a simple "change the MAC address" function could've gotten left out of some piece during a rewrite, because it otherwise does not affect basic functionality. I really recommend downloading the OSS from Apple and inspecting it; the pieces it copied from BSDs etc. are relatively stable, but the amount of churn in other pieces is surprising to see.

oneplane 7y ago
I'm not sure about the internal culture, but externally they seem to stress the importance of only using public published interfaces and frameworks as API & ABI layers and not touching anything else as they won't guarantee any stability in private internals. (per their docs iirc)
- LeoNatan25 7y ago
  Even with the so-called "public" APIs, the way Apple operates, there is no guarantee of any stability, as most iOS developers know. AppKit is much more stable than UIKit, but still nowhere near the stability that companies like Microsoft provide (including changing the name of a product—Windows 9->10—so that existing software does not break!). If you are using features of the frameworks that are outside of the "happy path" for that year's keynote announcements, you can expect terrible bugs on a yearly basis. These bugs happen for the exact same reasons as stated in the GP.
  - oneplane 7y ago
    But doesn't that go for anything? Take android where you need to account not only for all the cases of versions but also for every differentiated version from every brand and device, or if you build for things like silverlight which gets killed with no replacement. There are always things changing and unless you are on the same path as the vendor you're gonna get screwed. It's always been like that.

nickthemagicman 7y ago

What about via bash and ifconfig? Is this just a GUI thing?

deleted 7y ago

[deleted]

clubm8 7y ago

I had not tried in a long time. They have for a long time not allowed you to put airport into monitor mode easily, so I always just bought a USB wifi antenna for any wireless penetration testing. I'm surprised by this thought... is it not changable at all or just by the user? I know in iOS they had a feature to randomize the mac when searching out networks to increase privacy...

anonthrowaway28 7y ago

Running a hackintosh on 10.14.6 (18G103), works fine: $ ifconfig en1 ether en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 ether aa:bb:cc:dd:ee:ff It maybe related to wifi drivers. Index Refs Address Size Wired Name (Version) UUID <Linked Against> 37 10 0xffffff7f83b0e000 0x22000 0x22000 as.vit9696.Lilu (1.3.4) 7C0B7376-83CF-32DA-9C49-7052141EC730 <8 6 5 3 2 1> 38 0 0xffffff7f83b30000 0x5000 0x5000 org.vanilla.driver.CPUFriend (1.1.6) FFAD6CD3-E28F-3741-BE12-E44720F45CA6 <37 12 8 6 5 3 2 1> 39 0 0xffffff7f83b35000 0x4000 0x4000 com.rehabman.driver.USBInjectAll (0.7.1) 88901B62-E4A2-3374-A33C-873C8BC29F9C <13 12 5 3> 40 0 0xffffff7f83b3a000 0x3000 0x3000 as.lvs1974.BT4LEContiunityFixup (1.1.2) 1B490F7D-CD49-30AD-944A-553D0D99692C <37 8 6 5 3 2 1> 41 0 0xffffff7f83b3d000 0x4000 0x4000 com.sicreative.VoltageShift (1.1) 0FA3C2F1-BEA1-3AAF-AA39-3ED26996F2C1 <5 3> 42 2 0xffffff7f83b44000 0x11000 0x11000 as.vit9696.VirtualSMC (1.0.2) E9475ED7-4AB2-3DDE-B20B-614B06DAE65B <37 12 8 6 5 3 2 1> 44 0 0xffffff7f83b55000 0xa000 0xa000 ru.usrsse2.SMCBatteryManager (1) E0542A67-D72C-3FD4-A142-40B586E9CE50 <43 42 37 12 8 6 5 3 2 1> 45 0 0xffffff7f83b5f000 0x63000 0x63000 as.vit9696.WhateverGreen (1.2.7) 122F635A-DC40-3DF0-98AF-8505A83221C0 <37 13 8 6 5 3 2 1> 46 0 0xffffff7f83bc2000 0x102000 0x102000 as.vit9696.AppleALC (1.3.6) 3E1A3DF6-9D93-3DD0-96A0-9FBA5791D7D7 <37 13 8 6 5 3 2 1> 47 0 0xffffff7f83cc4000 0x6000 0x6000 as.lvs1974.AirportBrcmFixup (1.1.9) 6AE31546-1F21-303F-A51E-A34753C9905E <37 16 13 8 6 5 3 2 1> 48 0 0xffffff7f83cca000 0x3000 0x3000 xyz.racermaster.NoTouchID (1.0.1) 85F586AC-B564-304A-BCC0-55681EF86F91 <37 8 6 5 3 2 1> 49 0 0xffffff7f83ccd000 0x5000 0x5000 as.lvs1974.HibernationFixup (1.2.4) 8CA34F1A-5611-30B3-8224-53F093BF5FAA <37 8 6 5 3 2 1> 50 0 0xffffff7f83cd2000 0x5000 0x5000 as.vit9696.SMCProcessor (1.0.2) BB591E66-6993-39BB-88D9-D0936B92E036 <42 37 12 8 6 5 3 2 1> 67 2 0xffffff7f83cd7000 0xb000 0xb000 org.rehabman.voodoo.driver.PS2Controller (1.9.2) 53E0B467-6CA6-3CD1-A450-6A39D767DA8C <12 8 6 5 3 1> 81 0 0xffffff7f83ce2000 0x14000 0x14000 com.insanelymac.IntelMausiEthernet (2.5.0d0) D59B3731-D7AE-3CBA-A10F-4AB0C54AC05A <16 13 6 5 3 1> 88 0 0xffffff7f83cf6000 0xc000 0xc000 org.rehabman.voodoo.driver.PS2Trackpad (1.9.2) 1E85D11A-A05E-3FC3-AC6D-D28B7563B956 <67 57 18 8 7 6 5 3 1> 89 0 0xffffff7f83d02000 0x6000 0x6000 org.rehabman.voodoo.driver.PS2Keyboard (1.9.2) B974470A-CEE4-358B-B605-A09DFACEE4F4 <67 57 18 8 7 6 5 3 1> 99 1 0xffffff7f83d0c000 0x254000 0x254000 com.no-one.BrcmFirmwareStore (2.2.10) 4ED64118-8732-329E-A136-719F5CB78987 <6 5 3> 100 0 0xffffff7f83f60000 0x6000 0x6000 com.no-one.BrcmPatchRAM2 (2.2.10) B31288AE-941C-3064-8E7D-C00266BC302A <99 23 6 5 3 1>

huxflux 7y ago

This is one of the reasons I left macOS (and Apple).

Aissen 7y ago

Waiting a year for a driver fix for such a basic feature on widely used hardware, it makes Linux driver woes feel like a walk in the park.

fulldecent2 7y ago

Here is a legitimate practical use of editing your MAC: https://fulldecent.blogspot.com/2013/12/how-to-connect-your-roku-to-xfinitywifi.html https://fulldecent.blogspot.com/2013/12/how-to-connect-your-...