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Dual Boot Not Trusted, Rejected By Vista SP1
Posted by
timothy
on Wed Jul 30, 2008 03:28 PM
from the that's-south-of-luckless dept.
from the that's-south-of-luckless dept.
Alsee writes "Welcome to our first real taste of Trusted Computing: With Vista Enterprise and Vista Ultimate, Service Pack 1 refuses to install on dual boot systems. Trusted Computing is one of the many things that got cut from Vista, but traces of it remain in BitLocker, and that is the problem. The Service Pack patch to your system will invalidate your Trust chain if you are not running the Microsoft-approved Microsoft-trusted boot loader, or if you make other similar unapproved modifications to your system.
The Trust chip (the TPM) will then refuse to give you your key to unlock your own hard drive. If you are not running BitLocker then a workaround is available: Switch back to Microsoft's Vista-only boot mode, install the Service Pack, then reapply your dual boot loader. If you are running BitLocker, or if Microsoft resumes implementing Trusted Computing, then you are S.O.L."
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But what if... (Score:5, Interesting)
What happens on systems without a TPM?
Re:But what if... (Score:5, Funny)
It will detect the lack of a TPM and notify the FBI that you are probably a terrorist.
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Re:But what if... (Score:5, Funny)
Probably?
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Re:But what if... (Score:5, Funny)
Probably?
Close enough for government work.
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Re:But what if... (Score:5, Informative)
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Re:But what if... (Score:5, Informative)
Informative gives Karma but Funny doesn't. Therefore, people who appreciate the post and wish to give the user some karma will choose Informative.
What I don't understand is why anyone would care... Slashdot Karma is competing with Kool-Aid Fun Points for score that has the least impact on my life.
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Re:But what if... (Score:5, Funny)
If you want karma, be informative rather than funny.
This comment is informative, not funny.
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Re:But what if... (Score:5, Informative)
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Re:But what if... (Score:5, Informative)
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Re:But what if... (Score:5, Informative)
Not at all....
Booting is handled by the EFI, and any operating system booted under the legacy BIOS emulation wouldn't be able to do a thing about it!
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Re:But what if... (Score:5, Insightful)
Of course, the article says the problem exists even if you don't have the encryption enabled.... However it looks like what happens in that case is the same as what's always happened when a windows update contains a MBR change: It overwrites your third party bootloader. (Or in this latest case, forces you to do it yourself manually).
I'm failing to see why this is a big deal. Software is in place to check for a piece of third party code intercepting your encryption key... It successfully detects GRUB as such software, and stops. So what?
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Re:But what if... (Score:5, Insightful)
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Re:But what if... (Score:5, Interesting)
Not at all true. Security isn't binary. Bitlocker alone will stop 99% of attackers who try to get at your data through physical access. The rest probably won't bother with a trojan bootloader--they'll either use rubber hose cryptanalysis or a hardware keylogger, depending upon how stealthy they want to be.
I don't see a problem with Bitlocker using TPM in this way at all. But it should allow me to disable the bootloader check if I so choose.
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Re:But what if... (Score:5, Insightful)
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Re:But what if... (Score:5, Informative)
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Vista and Mac OS? (Score:5, Interesting)
Has anyone tried this with Boot Camp? I had no problems with Mac OS X and FileVault dual-booting with either XP SP2 or Vista base.
Re:Vista and Mac OS? (Score:5, Informative)
Intel Macs use EFI instead of a BIOS, and EFI uses GUID Partition Tables (GPT) instead of MBR.
The space that the MBR used to sit in is reserved in GPT, so when a legacy system reads, uses, or modifies the partition table, it only changes the old MBR partition table, which is not actually used to boot. In contrast, Boot Camp's dual-boot features only use the GPT, which means that as far as Vista knows, it IS the only boot loader involved.
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Whew (Score:5, Funny)
Good thing I'm running Mojave and not Vista.
It has a bootloader update. (Score:5, Insightful)
So... yeah. Anyone technical enough to change their bootloader should know how to put it back temporarily so it can get updated.
If you are running BitLocker, or if Microsoft resumes implementing Trusted Computing, then you are S.O.L.
I thought that was the entire point of BitLocker - don't unlock things unless you know that you're not running on top of some evil VM.
Not trusted for a reason (Score:5, Interesting)
If you are using BitLocker then you want your data to be secure. There are probably ways that a compromised boot loader can allow an attacker access to your data. Vista closes this security hole by requiring the boot loader to be a cryptographically signed binary that it trusts. If it didn't, this story would instead be "Vista BitLocker encryption not secure on dual boot systems".
That being said, there should be a way to register other trusted signature keys in Vista to allow 3rd party boot loaders. I don't know if there is or not, but there should be.
Re:Not trusted for a reason (Score:5, Insightful)
That's great...
Except for the fact that it happens on any system that CAN run BitLocker, rather than any system ACTUALLY running BitLocker.
So if you're trying to dual-boot between Linux and Vista Business/Ultimate and you have a TPM-capable machine, forget it: you're locked out until you restore the Vista bootloader.
Even if you're not using BitLocker.
Even if you've never even installed BitLocker.
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Re:Not trusted for a reason (Score:5, Insightful)
That being said, there should be a way to register other trusted signature keys in Vista to allow 3rd party boot loaders. I don't know if there is or not, but there should be.
That's exactly what's wrong with the Trusted Computing initiative that the major players (Microsoft, Intel, etc) are implementing: they don't trust YOU to make those kinds of decisions to trust 3rd parties.
http://www.againsttcpa.com/ [againsttcpa.com]
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Re:Not trusted for a reason (Score:5, Informative)
No, they do. I think a lot of people here misunderstand what TPM is meant to actually do and what it's supposed to be good for; and what it is useless for. (Frankly, I'm not sure Microsoft fully understood.)
It's because the MBR has *changed* that means the chain isn't signed with something that will allow the system state register to authenticate with the TPM key storage; the register contents will have changed because the SHA-1 fingerprints changed, so you're not going to be able to get a coherent response from the TPM regarding any keys you've stored in it if you've taken ownership already. Without resetting the token and destroying the keys, that is.
You want another way of doing this? Don't take ownership of the TPM to store the keys, but put 'em on a thumbdrive and use a secure passphrase (10 word Diceware, for example) to unlock them; this is also a supported mode of operation under BitLocker (assuming you trust the Elephant diffuser as being part of a reasonable cipher mode; frankly, I'm not that happy with it and prefer OCB or XTS modes, or failing that Linux's aes-cbc-essiv:sha256)... doing it the "thumbdrive way" is highly recommended when a TPM isn't available or wanted. Putting the hard disk encryption keys in the TPM isn't necessarily a good idea; they are recoverable given some effort, and that's not really what the TPM tech is for.
This is all entirely by design; it's closing an actual security hole whereby a trojaned MBR could capture your encryption keys. Obviously this is unsuitable for any dual-booting setup. TPM just isn't designed to work with that kind of scenario; it's really more of a system for verifying extremely stable system images such as you might find on a server or tightly-controlled corporate workstation that you want to be able to have a reasonable degree of confidence hasn't had the MBR tampered with because it's a trusted client that handles classified data (and any tampering with the software whatsoever would decertify it).
You control the chain of trust when you take ownership of the TPM; they do work just fine with Linux, and Linux does have support for them - if you want to know and prove to another system that the bootloader, BIOS, and kernel haven't changed since the state you knew was good, you can do that (although the proof is only as good as the integrity of the TPM).
They're just hardware tokens coupled with a signed BIOS/bootloader/kernel, really. Handling the actual key management that results from that, or what you do with it, is entirely up to you.
Vista using the TPM for BitLocker is hardly plug-and-play, and quite unsuitable for many scenarios (many TPMs out there don't even support TCG1.2); there's always TrueCrypt or PGP Whole Disk Encryption or one of the many other solutions available if you want a little more flexibility and control.
In particular, it's not really about DRM. None of the DRM systems proposed or deployed have ever used it, or are likely to ever use any part of it, as a key storage blackbox, because an entirely homogeneous image just isn't something you can guarantee on any consumer box (that's one reason it's not even on or in the vast majority of OEM and consumer motherboards/chips). It's perhaps a bit more practical for laptops...
Also, TPM implementations are quite breakable where the attacker has physical access and ownership of the machine and plenty of time. PCs aren't even consoles, and look what we've done to those...
It's meant to be one interlocking part of a whole enterprise security solution. It sure as heck isn't a "magic crypto chip" that will lock up your PC, and it shares none of the common criteria with DRM scenarios (which are, of course, just as doomed if they use a hardware blackbox as if they use a software blackbox, because the plaintext is always available...). In fact, having a TPM around if you're running Linux, will at least make sure you always have a secure entropy source for /dev/random...
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Summary Needs Re-writing (Score:5, Informative)
This *may* be a corner case as most TPM's were shipped in the disabled state back when XP was still shipping.
Instead, how about testing the open source BIOS stack? Most of you have an unused box of recent vintage and I'm sure the projects can use the feedback.
FYI: An open sourced bios is an Achilles heel for Microsoft. Mobo OEM's will **jump** on a Free bios because it saves them money and elminating TPM saves them much more money.
Get involved!!
http://www.coreboot.org/Welcome_to_coreboot [coreboot.org]
http://openbios.info/Welcome_to_OpenBIOS [openbios.info]
FDISK (Score:5, Funny)
c:\> FDISK /MBR /dev/hda1
Out of Memory
c:\> format c:
Out of Disk Space
c:\> edlin config.sys
File not found
c:\> set PROMPT=$
$ mke2fs
How is this news? (Score:5, Insightful)
Vista's security chain works as designed and intended, preventing from you to inject an untrusted bootloader into the bootstrap. Isn't that what we -want- from our security systems? This isnt' a case of "Microsoft" holding our data hostage, this is a case of our own security policies WORKING.
If I were to be running Linux, with equivalent protection, I'd be right pissed if it could be trivially rootkitted/bypassed by swapping in a malicious bootloader.
The ONLY flaw I see in the entire Vista/TPM system is that users don't seem to have a way of manually trusting things they genuinely want to trust. If it hasn't been blessed by MS its not trusted -- that's a fine policy for general users, but if I, as the hardware want to trust a specific bit of code (e.g. the linux boot loader) then I should be able to manually sign it somehow, and add my personal key to my personal install of Vista. And then the grub bootloader I signed will be trusted on my (and only my) PC.
All the 'chatter on the internets' is currently centered around how to disable UAC, how to disable driver signing, how to go back to running windows as insecurely as possible. i would prefer to see the discussion take a more intelligent direction -- how to obtain keys/certificates, how to add them to Vista's chain of trust on a per PC or per domain basis, and how how sign code with them.
Signed drivers are a FANTASTIC idea. not being able to sign drivers myself for my own hardware is EVIL. But MS --does-- have programs in place to let you sign code with 'development drivers' which are designed to only be valid on your PC... its just that most of the discussion surround the issue is how to disable it, and how evil MS for deciding what is blessed and what is not.
I mean, take Stallman, even -he- who wrote the GPLv3 in part to counter DRM isn't against code signing. He just requires that the keys necessary to sign code be included, so the owner of the hardware and user of GPLv3 code can sign it, and thereby be free to make modifications and excercise all the freedoms intended by the gpl.
Re:How is this news? (Score:5, Insightful)
I mean, take Stallman, even -he- who wrote the GPLv3 in part to counter DRM isn't against code signing. He just requires that the keys necessary to sign code be included, so the owner of the hardware and user of GPLv3 code can sign it, and thereby be free to make modifications and excercise all the freedoms intended by the gpl.
Right which is the antithesis of what "trusted computing" is all about. Trusted computing is all about allowing vendors like microsoft to trust the computer to work in thier partners interests rather than the users.
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Re:How is this news? (Score:5, Insightful)
Vista's security chain works as designed and intended, preventing from you to inject an untrusted bootloader into the bootstrap. Isn't that what we -want- from our security systems? This isnt' a case of "Microsoft" holding our data hostage, this is a case of our own security policies WORKING.
If I were to be running Linux, with equivalent protection, I'd be right pissed if it could be trivially rootkitted/bypassed by swapping in a malicious bootloader.
If the attacker can install a bootloader, that means you were rooted and your precious data can be grabbed from the memory of the program that happens to be using it.
If the bootloader is installed while the OS is not running, that means you do not have adequate physical security.
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It is by design... (Score:5, Insightful)
This is by design. If you are into the secure boot stuff you'll know why.
This is not about DRM and such (but may be) but about *your* data encrypted by BitLocker (the DRM is about protecting *somebody else's* data from you - that is why it is flawed concept).
Right now there are some kinds of attacks that let you compromise the entire system right from boot (using other than approved bootloader and unsecure boot proces) puting it into hypervisor and thus being able to retrive keys and such directly from memory.
In fact I don't see any other option as to control entire boot proces. And if you wish to control it you need to use tools that support it.
So in fact it is not a Bad Thing. It could be a bad thing if you are casual-security user - but this 'casual security' is not so secure isn't it?
I bet BitLocker documentation covers that. But why bother checking? It is better to set the "secure" option to "on" and dumbly belive it.
Re:You can use the Vista boot loader (Score:5, Insightful)
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Re:You can use the Vista boot loader (Score:5, Funny)
It's only Windows that doesn't give choice
I have heard that is a feature that we pay extra for.
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Re:You can use the Vista boot loader (Score:5, Interesting)
Any idea whether this is a problem in dual hard drive systems? I found it simplest with Vista to unplug my Ubuntu hard drive, plug in my Vista hard drive, and install Vista as though it were the only operating system. Then I plug Unbuntu back in and add the chainloader line to Grub pointing to the Vista drive, which still has its own "boot sector" on the other drive.
(This has the added bonus of allowing me to boot to the other OS should one of them fail--though one guess as to which one has that tendency d-_-b)
Or have I misunderstood the problem? (a distinct possibility, I avoid "Trusted" computing wherever possible)
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Re:You can use the Vista boot loader (Score:5, Interesting)
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Re:You can use the Vista boot loader (Score:5, Insightful)
Put windows on the first hard drive, then install linux on the second hard drive. Setup grub so it chainloads the windows boot record (for one of the options), and finally make your bios boot off the second hard drive.
Then Windows is happy and ignorant of its true surroundings.
Thats how my dualboot desktop at home is setup.
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Re:You can use the Vista boot loader (Score:5, Interesting)
Because their customers want them to.
Using the Windows boot loader to chainload code off another partition is, AFAIK, impossible.
Besides, in Vista the nice, easy-to-modify boot.ini file is gone. It is replaced by yet another binary registry-like database. Typical Microsoft.
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Re:You can use the Vista boot loader (Score:5, Informative)
Date of article you reference: October 13, 2006
Date of KB935509 [microsoft.com] update which breaks this: January 7, 2008
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Re:You can use the Vista boot loader (Score:5, Insightful)
That's nice. The Windows idea of supporting it is "go look on technet" versus
the Linux version where it's already built-in and configuration is done for
you automatically.
This precisely the stupidity that Windows trolls like to accuse Linux of
subjecting the end user to.
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Re:You can use the Vista boot loader (Score:5, Informative)
Windows allows multi-OS booting; yes, even Vista allows it. You just have to know how to do it; just like any dual boot scenario.
False. Your solution requires hackery, while many Linux distros together with most things except Vista takes care of setting up dual-boot during the installation process.
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Linux under windows = untrusted too (Score:5, Insightful)
In which case you can no longer trust linux.
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Re:You can use the Vista boot loader (Score:5, Funny)
I'm hoping some joker with the next viable vista virus uses it to trigger trusted computing into locking machines.
Lets see vista's adoption rate when word gets out it bricks your entire system if you get a virus.
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Re:You can use the Vista boot loader (Score:5, Informative)
Just games? There are lots of people who run windows as their primary OS (because it's what they are used to after spending 15+ years on a MS platform, or maybe because there are apps they rely on that aren't available elsewhere), and they dual boot Linux because they want to be able to hack around, learn more, and generally have fun.
Taking an interest in Linux does not automatically mean somebody will abandon Windows the next morning.
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Re:Only a problem if you have TPM? (Score:5, Informative)
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Re:Only a problem if you have TPM? (Score:5, Informative)
I have Vista Enterprise on a dual boot laptop with a TPM that I have never enabled. Installing SP1 did nothing adverse to the dual boot capability.
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Re:Only a problem if you have TPM? (Score:5, Interesting)
(I, however, use the Windows boot loader.)
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Re:Only a problem if you have TPM? (Score:5, Insightful)
> Never Trust Trustworthy computing. it hasn't earned it.
Trusted Computing.
There's a big difference between Trusted and Trustworthy. As this update proves.
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Re:Only a problem if you have TPM? (Score:5, Funny)
If I read TFA correctly, you need to have been using your TPM to experience this problem?
I have not been using my TPM and I was scolded on Monday about not using TPS report coversheets. Are the two related?
Thanks, Peter Gibbons
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Re:Who cares? (Score:5, Informative)
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Re:Who cares? (Score:5, Informative)
Two words: filesystem support.
Boot up Linux and all the stuff on your NTFS partition is read-only.
What? You know, Linux has had full NTFS Read/Write support for a while now, see :
http://www.linux-ntfs.org/ [linux-ntfs.org]
Also, ever heard about WUBI [wubi-installer.org] ?
jdb2
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Re:Affects crack? (Score:5, Insightful)
You know, I had to use that crack to get my copy of Vista reinstalled (all the partitions got wiped out, including the OEM one), because it refused to use my OEM key without the OEM partition, and simply wouldn't active. So, I had to crack my already-paid-for copy of Vista. Oh, sure, I could have gone and sent it back (to Acer, yeah right), or called Microsoft, but isn't it funny that I get a better "customer service experience" from cracked software?
Posting anonymous for the above reasons.
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Re:That's why I don't use Vista (Score:5, Insightful)
No, they just disagree who the owner is :)
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