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Using MAC Address to Uniquely Identify Computers
An anonymous reader writes "One of Australia's gaming networks, GamesArena has recently imposed a third party program required to access their gaming servers. One of it's features is that it records your NIC's MAC address to identify your computer, and subsequently in future, ban you if you cheat/break the rules etc. The response from players is mixed. It is not open source software, nor is it optional to install. "Install it or find another server to play on". Question remains, is it going too far?"
Definitely not- unfortunately it won't work since MACs are changable.
not banned anymore :D
What would Brian Boitano do?
1) Get your mac adress banned
2) Sell Network Card
3) Some one buys new card
4) They are banned
There will be plenty of second hand NICS for sale becuase of this. its a 1 2 3 profit plan.
Linksys routers (and otherS) allow you to "clone" the MAC address. Its very useful if your cable company has registered the MAC address of the NIC they gave you. Thus, with filtering software, any other NIC won't connect....unless you "clone" it :)
It's all too easy. Figure out their IP, get their MAC, put it on your router, get banned, change your MAC back, enjoy your new unopposed domination.
Too many violations from that IP range? Ban the /24 it came from. Send back a "Too many cheaters from your ISP" error.
MACs are too easily changed, but then again, so are IP's. But considering most gamers have DSL with a static IP, an IP ban is a much better option.
Uh, that might actually BE the point - anyone with $10 for a new NIC can change their MAC address, no brains required...
;-)
If you have brains, you can save $10...
Mark
As if people whining on CounterStrike weren't bad enough, now we have to listing to 14 year olds complain about having to buy a new NIC every time they cheat online.
"It's hard to be a man when there's a gun in your hand"
...until the MAC address generators have gone through all the "MAC-space" of possible addresses...
Wireless APs like Linksys' already come with a web admin that lets you specify *any* MAC address, apparently to please some cable/adsl providers that measure traffic/authenticate (partly) based on this.
Why not provide a public key server and ask people to submit they public OpenPGP key, signe by P. Zimmermann himself ? Get your identity trusted by Z. or go play somewhere else... After all, this seems to imply they want "real" players!
Notepad specialist & FAT administrator, group training available
There's really no need to change your MAC address.
They're violating the simple rule about never trusting the client. All you have to do is modify this third-party program to have it spit out a random MAC address each time and *poof* the system is worthless. You don't even have to change your MAC address. And since MAC addresses are only used at the Ethernet level, not at the [TCP|UDP]/IP level, it doesn't matter that the server thinks your MAC address is different than it is.
They've been trying this crap for years with cable modems. Until I got a router, I used to use two different machines, each with the same MAC address installed. Worked out great. It's easy to change, too. It's also let me on at friends' offices, where access is MAC controlled. We log on a machine, write down the address, shut it down, boot mine up, change the address, and log on.
Who does it stop? Honest people.
Who won't it stop? The same people hacking their games in the first place.
The power of accurate observation is commonly called cynicism by those who have not got it. - G.B. Shaw
ifconfig eth0 hw ether aa:dd:rr:ee:ss
Uh, no you won't. The only time MAC addresses make a difference is in ARP packets, and the only place MAC addresses make a difference is on your local LAN segment. The fact that two people in different cities have the same MAC address matters not a whit to the routers between them.
...phil
"For a list of the ways which technology has failed to improve our quality of life, press 3."
I keep a fresh supply of token ring cards handy to swap out if the need arrises.
And im not joking:
http://gambit32.org/albums/other/aag.jpg
No, it's not going too far. The game server admins can run the server however they choose fit. If you don't like the rules, don't use the server!
However, the majority of people don't know how to reset their MAC addresses. Also, as I believe to be true, some broadband providers specifically use MAC addresses to verify access. For instance, my Comcast cable modem does everything by MAC, so if I change my NIC in my machine, I need to power off/on the cable modem in order to get back through to the Internet. Although this is sort of a minor issue, some other ISPs may be more strict about MAC changes.
Overall, the admins figure they will cut out 99% of the hacking attempts as people would just go elsewhere, or once they did cheat, just wouldn't know how to change their MAC.
What happens if you are logged in via dial-up? Will it ban the MAC address of the box at the ISP that you're dialed in to? :)
NAT routers such as the Linksys range allow you to specify the MAC address from their web-based setup - ideal if your broadband provider insists on you registering (and limiting the number of) MAC addresses of all the machines going to connect.
I wonder what they'll do when they discover several simultaneous connections to the server (and sessions) from the same MAC?
The only thing you can accurately describe as "Scotch" is a sticky tape made by 3M. And it's
Does not the current IPv6 address allocation standard specify using your MAC address as the suffix portion of the IPv6 address? This is merely a taste of things to come if/when IPv6 becomes widely deployed, when your very IPv6 address can uniquely identify the hardware you are on (unless you use IPv6 NAT, of course.)
And yes, presently, you can probably change the MAC address of your system. However, once software vendors and DRM technologies and other things start locking themselves to your computer hardware, I suspect changing the MAC address would cause problems. The only thing this game company has to do is when the game is installed is to lock the licence to the present MAC address so it will not run with a changed IP address without a new licence.
here's how to change it for nt/2000
windows2000faq
-advanced tab in adapter properties
linux
eepro100 list
-ifconfig eth0 hwaddr ether 00:11:22:33:44:55
this is exactly why microsoft's registration process uses a lot more than just the mac address.
Nope, MAC addresses won't work. You'd have to have a unique number that's hard coded into something expensive. The Pentium III's CPUID feature would work. However, as much as I hate cheaters in my favorite games, I don't like an ID number open to abuse.
Quake III has recently enabled anti-cheat software called Punk Buster. It does a ban via your Quake III CD-Key, so you can't play on any Punk Buster enabled servers if you get banned. But with the game under $20 at BestBuy, I'm not sure if it will stop many of the problems.
Cthulhu Saves.
But if you're on the same segment, then routing is not an issue.
As noted, the answer is trivial: generate random MAC addresses. They are 6 bytes long - plenty of room for everyone to tumble the address every day and still not collide.
...phil
"For a list of the ways which technology has failed to improve our quality of life, press 3."
When I was involved with the initial deployment of DSL service in Canada, our customer ran into an interesting problem: many of the low-cost NICs that they shipped with the DSL modem had the same MAC.
Under most circumstances, this is seldom an issue since the NICs aren't likely to be deployed on the same network segment. However, when the MAC is used for other tracking services (in this case, a layer-2 NAT), you have a problem.
And of course, as others have said, most NICs permit the factory MAC to be overridden.
>"...Question remains, is it going too far?" Definitely not-
Thanks for answering that one for us. Without your moral framework we would be lost in the chaotic hell of self determination.
Why stick up for big business?
This has been going on for a while, though without MAC addresses, a much simpler system. Most multiplayer games thesedays come with a CD-Key thats authenticated by a central server whenever you play a game. The CDkey usually has a unique ID strapped to it that is publically accessible by admins or players. You ban the ID, they cannot connect to the game without changing their CDkey (which means either buying a new copy or finding another cdkey that works online, neither are 'easy'). If MAC addresses can be changed, then as soon as a couple of like-minded gamers find out about that, you can count on their being a guide on how to do it for gamers eventually. The best way handle this is on both a MAC, and CDkey-ID level. Ban their MAC, and ban their ID, that will stop all but the most determined/knowledgable.
"What can a thoughtful man hope for mankind on Earth, given the experience of the past million years? Nothing." -Bokonon
Many ethernet drivers with this capability have an option for just this. For example, if you have a 3c918, click "configure" under network properties in win2k for that adapter. Select the "advanced" tab. On the left, you'll have an option called "network address" that's normally set to "Not Present". Change it to a specified value, and type in "DEADBEEFBABE" or whatever MAC address you want.
Bingo.
Black holes are where the Matrix raised SIGFPE
It's solid code of honor amongst Clans not to cheat. Anybody as dedicated to playing online action games would render his pasttime pointless by cheating. And if anyone found out you've cheated your way into Ladder position you'd get an extremely hard time (on and offline).
:-)
And when you're playing on a public server, cheaters are easyly identified by playing like crap and either scoring immediate kills once they actually *do* manage to hit or by simply not throwing the towel no matter how many times you flak them at point-blank. Both area mostly less than minor drags to a skilled player and have a somewhat funny aspect to it.
I've seen entire matches in UT (1st) where cheaters we're just plain ignored because of the simply fact their skill level (not trained by playing under real conditions) rendered them something more like 'moving obstacles' rather than actuall participants.
Anyhow, some one using more subtle cheats, such as see-through textures or so, can be anoying. Then on the other hand, if you're that good to know for shure that someone is using such a cheat, you'll be playing clan games most of the time anyway. And I haven't met a single Clan player cheating yet. At least none of mentionable Clans.
BTW: I once had a cheater on my team in a pub UT CTF match. I switched sides and telefragged him 'til he gave up and disconnected. That was fun.
We suffer more in our imagination than in reality. - Seneca
I wonder how many people will change theirs to same as mine...
-- bartman
Whether it's in the name of catching cheaters or catching terrorists, our freedom and autonomy are about to evaporate.
If there's one card on a network, and you add another, the question becomes "what are the odds that the two cards will pick the same number?" Since there's 48 bits of entropy(minus a small range for multicast addresses and broadcast), the odds are effectively 2^48.
This is big.
If there's many cards on a network, and you want to know how many total you can add before two of them will end up with the same card, the answer's far smaller -- 2^24, which is still pretty huge(it's a bit more than 16 million). It's a different problem because each time you add a new card, the card after has one more it can possibly match with. This is known as the birthday paradox, so named because this precise logic means that given 23 people in a room, there's a +50% chance that two people have the same birthday. Each new person is one more to match with.
In reality, this is a moot point: MAC address prefixes are assigned by manufacturer, and the manufacturer serializes their cards such that no two shipped devices should ever have the same MAC address. Sometimes there are screwups, but they're pretty rare as far as I know.
To debunk what a couple people are saying -- yes, MAC addresses as exposed to the network can be changed, but MAC addresses as detected by custom client software may be more tricky. Whatever the driver is exposing to the network, the card itself can't usually have its MAC address written over(i.e. once power is cycled, that card's returning to original shipped condition). I'm positive there are exceptions to this, but they're probably rare.
Actually, this gives me an interesting idea. You can probably remotely fingerprint the age of a computer based on the MAC address of its ethernet card...and if IPV6's MAC->IP shove goes through, you'll be able to do that reasonably remotely!
Yours Truly,
Dan Kaminsky
DoxPara Research
http://www.doxpara.com
Simple: if you are winning at Counter Strike despite a ping of 1,000+, then you must be cheating.
I mean, duh...
--- My dad's political betting
It is a typo for "Tolkien Ring", a system in which the computer that holds the "One True Ring" becomes the most powerful machine on the network.
I metamoderate, therefore I am
It seems people tend to confuse privacy with anonymity. Privacy means preventing others from getting information about you -- whether it's what kind of toothpaste you use or your SSN. Anonymity means preventing others from finding out who you are. The two are related, in that in practice they often go hand-in-hand. But they are distinct.
-Thomas
Great. This is another way to get rid of those pesky, honest players and my enemies.
I'll just assume their MAC address, misbehave like hell. Their MAC gets banned, and I get rid of the losers.
Alone, I shall reign through spite and malice.
Stop the brainwash
Since the ifconfig man pages contain instructions on how to change MAC addresses and
Since changing the MAC address would allow a cheater to circumvent access controls
Then are the ifconfig man pages now illegal in the US under the DMCA?
Further, anybody who's smart enough to figure out how to change MAC addresses can also figure out that they can assign their own static IP address from the DHCP pool and the DHCP server will often allocate around it.
Off-topic, but I used to do that when I had a cable modem. One day, however, I typo'd the ifconfig command on FreeBSD, and accidentally took over the router's IP (I mixed up my IP with the gateway IP). My phone promptly rang... they didn't much like that. Seems I took out service for the whole area, and they had to reset the router.
Good thing this was before 9/11 and all the crazy computer crime laws...
NGWave - Fast Sound Editor for Windows
I work tech support at a small liberal arts college, and we require all students to register their machines within three weeks of getting on campus. We then lock their ports to their MAC addresses. If you need to move or change your card you can re-register, usually the change goes through in a day. We did it to make it easier to detect and limit email worms. If we see it coming from some specified port we close it off and the flag passes to the techs. So far it's worked pretty well, often we get people coming to us complaining that "their Internet doesn't work," usually it's because they got Klez and we shut their port off. Decent alarm system, really.
No statement is true, not even this one.
You can ban CD keys. Basically the only way around that is to buy a new copy of the game, which I doubt many people are willing to do.
Teh CD keys are also an effective anti-piracy measrure, and one that isn't bothersome to legit users. When you are using the game for local play, the CD key doesn't matter, it's never checked. When you play on the Internet, however, the CD key is authenticated.
When you first go to play multiplayer games, you client talks to the master server and lets it know what it's key is, the server chekcs and authenticates this against its list. Then, when you connect to a server the server checks your key, and asks the master if this is a legit key and if that key has authenticated. If not, the server refuses the connection.
Hence, you can ban a CD key, and be very certian that the person it belongs to has been completely banned. Things like key generators aren't effective because while they can know the algortihm used to make legit keys, the keyspace is huge and they have no way of knowing which are actually legit and which aren't.
So it ends up working out pretty nice for both parties. Bioware gets some copyprotection that there is actually a reason for srever owners to want to use.
Q. How can I change my media access control (MAC) address under Windows NT 4.0?
c es\\Parameters.
A. Each network adapter card has a MAC address, which machines on local subnets use to talk to each other. MAC addresses are usually burned into the adapters during the manufacturing process. To overwrite a network adapter card's default MAC address, perform the following steps:
1. Start the registry editor (e.g., regedit.exe).
2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servi
3. From the Edit menu, select New - String Value.
4. Type a name of NetworkAddress, and press Enter.
5. Double-click the new value, and enter the adapter's new MAC value.
6. Click OK.
7. Close the registry editor.
8. Reboot the machine.
This makes me very happy- One should be able to deliver their cutting remarks and wage psychiological warfare upon the weak with one liners like "Yeah thats what your mom did last night, cock jocky."
That is the essence of multiplayer gaming, and any attempt to deprive us of that should be fought bitterly.