6 ms·

Full-disk encryption for all computer drives, coming soon

27 points by nreece 18y ago

rw 18y ago
Will we still own our data?
- ramchip 18y ago
  I was kind of worried when I saw "Trusted Computing", but having read the article I don't think there's any DRM-related use for it. It's really just HD encryption.
  - tptacek 18y ago
    "Trusted Computing" is a bit of a bugbear; the technology behind it is totally inevitable and fundamentally innocuous. All it's saying is, the OS should be able to extract the promise of a secure channel to the chipset and the hardware. Without that promise, you lose your machine just once to a piece of malware and you can never trust it again.
    - Herring 18y ago
      Only a fool would give up control over his computer because he's afraid of wiping it. You can bet your last dollar that promise will be enforced against you as well.
      - tptacek 18y ago
        Who said anything about "giving up control over your computer"? Do you actually know anything about Trusted Computing, or this just propaganda? The TPM specs are public, the programming interface is public, and if you don't like how your software uses it, write different TPM software. Your problem is with Microsoft, not with hardware security. If you don't like Microsoft, don't run Windows.
    - mindslight 18y ago
      I wouldn't call the idea of physical access not being the highest level (to hardware state) particularly innocuous. From the article - "You can't even sell it [a stolen drive] on eBay". Theft deterrence is nice, but the piles of bricked drives left over from xbox upgrades are disgusting. The same eviction of malware can be achieved through a documented hardware interface to the lowest levels of microcode (say, JTAG). The current problem is not due to openness, but closed CPU microcode.
      - eru 18y ago
        > The same eviction of malware can be achieved through a documented hardware interface to the lowest levels of microcode (say, JTAG). The current problem is not due to openness, but closed CPU microcode. Would you please elaborate?
        mindslight 18y ago
        kragen's comment hits the nail right on the head. Any software update system suffers from the ability to install a "rootkit" that can emulate the update mechanism itself to ensure its own survival. I was mistaken in thinking that CPU microcode was stored in non-volatile memory on the CPU itself, but the same idea goes for any area in which such rootkits can be installed. The simple solution is to allow easy updating of that base firmware through a dedicated hardware interface. A socketed DIP isn't hip anymore (eww through-hole), but a USB device header on the motherboard would certainly work. I'd feel better about trusted computing technology if one of their design goals wasn't preventing physical "tampering" but instead they provided unfettered access through a debug port. However, it seems like they're aiming for the exact opposite in order to facilitate naive software, theft deterrence, and business model preservation.
        tptacek 18y ago
        Can you explain more about how the TPM facilitates naive software and business model preservation? That's not my experience with it, but maybe you've had a different experience.
    - kragen 18y ago
      Maybe it would be better if the machine's owner could extract that secure channel, rather than the OS. For example, if you could reflash the BIOS with a JTAG header on the motherboard, then you could be sure that no compromised BIOS code survived (unless your JTAG programmer was broken). Or you could have a boot monitor in non-Flash ROM that could checksum the Flash BIOS, and then you could compare the checksum to the version before the malware ran, and pop the Flash chip out of its socket to replace it if necessary. Does that answer the threat model you're thinking of? A lot of the stuff under the "Trusted Computing" rubric goes a lot further than what you're describing. Some of it is designed to allow third parties (other than the OS and the machine's owner) to establish a secure channel to the chipset and the hardware over the network. That is almost certainly a bad idea.
      - tptacek 18y ago
        The "secure channel to the chipset over the network" is just a public key pair in a chip. You can use it however you want, or not use it at all. There's no system built in to the TPM that allows your chipset to go talk to Microsoft without your permission. Obviously, if you give Microsoft permission to own your machine, it can go talk to Microsoft.com anytime it wants. But it already could without the TPM.
        kragen 18y ago
        A public-key pair in a chip is way overkill for the threat model I was talking about. Is it the same threat model you were talking about? You didn't answer that question. And while it's perhaps necessary and desirable that our machines contain tamper-resistant chips with public-key pairs in them, it's neither necessary nor desirable that the private key be secret from the machine's legitimate owner, which is part of the TCG scheme.
        tptacek 18y ago
        The key isn't kept secret from the machine's legitimate owner, Kragen. For instance, TPM keys need to be migratable. Do you spend a lot of time working with TPM/TCG technology? I don't want to sound patronizing; maybe it's me that's missing something.
TomOfTTB 18y ago
My problem with encryption technology like this is that it falls into that gray area between theoretically useful and actually useful. Equivalent software encryption has existed for a while (it's built into Vista for example). But when you read about these Government or Financial laptops getting stolen with people's private information on them they're never encrypted. Why? Because any info that's valuable is too valuable to risk losing just because someone lost the password. I mean, he says it himself... "it can't be brought back up and read without first giving a cryptographically-strong password. If you don't have that, it's a brick. You can't even sell it on eBay." So when you deploy this kind of thing you have to ask yourself if there's any circumstance under which that password could get lost. I'm not against the technology I just don't know a lot of people who will be brave enough to use it.
- tptacek 18y ago
  I don't want to comment much on a story from a trade rag like Computerworld, especially when it ignores the fact that we already have better options than this press release product. But, I'll take a moment to correct you: In many F-500 companies, disk encryption is already a corporate standard on all laptops; the organizations that are worried about losing passwords keep escrow keys. The problem people are trying to solve is, if you leave your car unlocked and lose your laptop, you don't have to cut a press release about how many SSNs you just lost.
  - TomOfTTB 18y ago
    I don't deny that there are ways in which encryption can be very useful and that a very organized company can guard against ever losing their data because of a password mishap. I'm just saying I've never met one of these companies and I've done my fair share of consulting work for companies large and small, People are used to security that can be circumvented if need be (through an administrators password or at worst a disk recovery service). When you're talking about hardware based encryption that option is no longer on the table and I think that rightfully makes a lot of people uncomfortable. In that way it's a huge risk. Which is why things like bitblocker (again, built into Vista) don't get used.
jwr 18y ago
That kind of encryption is useless, because I can't audit it. How do I know my data really IS encrypted and the key isn't just stored on the drive itself?
- moe 18y ago
  Yup. And who tells me that the manufacturer doesn't keep a master key to himself? When I go so far as to encrypt my drive then I'd rather use an open source product that I can download and compile myself. Not that I'd ever actually audit the source code myself - but at least I can be reasonably sure that multiple independent third parties have done it for me.
- tptacek 18y ago
  Proprietary hardware encryption schemes are assessed by third parties all the time. If you just aren't comfortable with anything but open source, that's fine. But you already rely on plenty of other security systems you can't audit.
  - jwr 18y ago
    I don't. And I really do believe that I should be able to audit any security solution I use. I don't understand what you mean by "Proprietary hardware encryption schemes are assessed by third parties all the time". Sounds like corporate speak to me. First, any "proprietary encryption scheme" is rubbish, and second, I should be the one to assess it. My point with the drive encryption solution was that you are told that your data is encrypted, but you have no way of checking it yourself. What if encryption is disabled in your drive? Can you tell? The final output of any encryption solution needs to be independently accessible, so that you can verify if it resembles white noise (which it should, ideally).
    - khafra 18y ago
      If you really want to know, you could always unplug the drive, plug it into another computer, and try your best to recover data--but other people are trying that; people like tptacek, and you could just rely on their assessments.
ks 18y ago
How will this affect data recovery?
- mzexfswlkr 18y ago
  If you know the passwd then tools going through the drive will not change. If you have to remove the PCB and replace it with one from another drive or you have lost the passwd then you are stuffed. Unless of course the drive maker has built in a backdoor - from past experience of security on PCs the unchangeable security passwd will probably be 'seagate'
- ks 18y ago
  THIS IS NOT MY COMMENT. I don't know what happened, but there must be a glitch somewhere in the software. I doubt someone has bothered to crack my account, Most likely there is a bug that attributes other posts to my user. This is the second post that is not written by me. Does HN have a place to post bugs?

27 points by nreece 18y ago

rw 18y ago

Will we still own our data?

ramchip 18y ago
I was kind of worried when I saw "Trusted Computing", but having read the article I don't think there's any DRM-related use for it. It's really just HD encryption.
- tptacek 18y ago
  "Trusted Computing" is a bit of a bugbear; the technology behind it is totally inevitable and fundamentally innocuous. All it's saying is, the OS should be able to extract the promise of a secure channel to the chipset and the hardware. Without that promise, you lose your machine just once to a piece of malware and you can never trust it again.
  - Herring 18y ago
    Only a fool would give up control over his computer because he's afraid of wiping it. You can bet your last dollar that promise will be enforced against you as well.
    - tptacek 18y ago
      Who said anything about "giving up control over your computer"? Do you actually know anything about Trusted Computing, or this just propaganda? The TPM specs are public, the programming interface is public, and if you don't like how your software uses it, write different TPM software. Your problem is with Microsoft, not with hardware security. If you don't like Microsoft, don't run Windows.
  - mindslight 18y ago
    I wouldn't call the idea of physical access not being the highest level (to hardware state) particularly innocuous. From the article - "You can't even sell it [a stolen drive] on eBay". Theft deterrence is nice, but the piles of bricked drives left over from xbox upgrades are disgusting. The same eviction of malware can be achieved through a documented hardware interface to the lowest levels of microcode (say, JTAG). The current problem is not due to openness, but closed CPU microcode.
    - eru 18y ago
      > The same eviction of malware can be achieved through a documented hardware interface to the lowest levels of microcode (say, JTAG). The current problem is not due to openness, but closed CPU microcode. Would you please elaborate?
      - mindslight 18y ago
        kragen's comment hits the nail right on the head. Any software update system suffers from the ability to install a "rootkit" that can emulate the update mechanism itself to ensure its own survival. I was mistaken in thinking that CPU microcode was stored in non-volatile memory on the CPU itself, but the same idea goes for any area in which such rootkits can be installed. The simple solution is to allow easy updating of that base firmware through a dedicated hardware interface. A socketed DIP isn't hip anymore (eww through-hole), but a USB device header on the motherboard would certainly work. I'd feel better about trusted computing technology if one of their design goals wasn't preventing physical "tampering" but instead they provided unfettered access through a debug port. However, it seems like they're aiming for the exact opposite in order to facilitate naive software, theft deterrence, and business model preservation.
        tptacek 18y ago
        Can you explain more about how the TPM facilitates naive software and business model preservation? That's not my experience with it, but maybe you've had a different experience.
  - kragen 18y ago
    Maybe it would be better if the machine's owner could extract that secure channel, rather than the OS. For example, if you could reflash the BIOS with a JTAG header on the motherboard, then you could be sure that no compromised BIOS code survived (unless your JTAG programmer was broken). Or you could have a boot monitor in non-Flash ROM that could checksum the Flash BIOS, and then you could compare the checksum to the version before the malware ran, and pop the Flash chip out of its socket to replace it if necessary. Does that answer the threat model you're thinking of? A lot of the stuff under the "Trusted Computing" rubric goes a lot further than what you're describing. Some of it is designed to allow third parties (other than the OS and the machine's owner) to establish a secure channel to the chipset and the hardware over the network. That is almost certainly a bad idea.
    - tptacek 18y ago
      The "secure channel to the chipset over the network" is just a public key pair in a chip. You can use it however you want, or not use it at all. There's no system built in to the TPM that allows your chipset to go talk to Microsoft without your permission. Obviously, if you give Microsoft permission to own your machine, it can go talk to Microsoft.com anytime it wants. But it already could without the TPM.
      - kragen 18y ago
        A public-key pair in a chip is way overkill for the threat model I was talking about. Is it the same threat model you were talking about? You didn't answer that question. And while it's perhaps necessary and desirable that our machines contain tamper-resistant chips with public-key pairs in them, it's neither necessary nor desirable that the private key be secret from the machine's legitimate owner, which is part of the TCG scheme.
        tptacek 18y ago
        The key isn't kept secret from the machine's legitimate owner, Kragen. For instance, TPM keys need to be migratable. Do you spend a lot of time working with TPM/TCG technology? I don't want to sound patronizing; maybe it's me that's missing something.

TomOfTTB 18y ago

My problem with encryption technology like this is that it falls into that gray area between theoretically useful and actually useful. Equivalent software encryption has existed for a while (it's built into Vista for example). But when you read about these Government or Financial laptops getting stolen with people's private information on them they're never encrypted. Why? Because any info that's valuable is too valuable to risk losing just because someone lost the password. I mean, he says it himself... "it can't be brought back up and read without first giving a cryptographically-strong password. If you don't have that, it's a brick. You can't even sell it on eBay." So when you deploy this kind of thing you have to ask yourself if there's any circumstance under which that password could get lost. I'm not against the technology I just don't know a lot of people who will be brave enough to use it.

tptacek 18y ago
I don't want to comment much on a story from a trade rag like Computerworld, especially when it ignores the fact that we already have better options than this press release product. But, I'll take a moment to correct you: In many F-500 companies, disk encryption is already a corporate standard on all laptops; the organizations that are worried about losing passwords keep escrow keys. The problem people are trying to solve is, if you leave your car unlocked and lose your laptop, you don't have to cut a press release about how many SSNs you just lost.
- TomOfTTB 18y ago
  I don't deny that there are ways in which encryption can be very useful and that a very organized company can guard against ever losing their data because of a password mishap. I'm just saying I've never met one of these companies and I've done my fair share of consulting work for companies large and small, People are used to security that can be circumvented if need be (through an administrators password or at worst a disk recovery service). When you're talking about hardware based encryption that option is no longer on the table and I think that rightfully makes a lot of people uncomfortable. In that way it's a huge risk. Which is why things like bitblocker (again, built into Vista) don't get used.

jwr 18y ago

That kind of encryption is useless, because I can't audit it. How do I know my data really IS encrypted and the key isn't just stored on the drive itself?

moe 18y ago
Yup. And who tells me that the manufacturer doesn't keep a master key to himself? When I go so far as to encrypt my drive then I'd rather use an open source product that I can download and compile myself. Not that I'd ever actually audit the source code myself - but at least I can be reasonably sure that multiple independent third parties have done it for me.
tptacek 18y ago
Proprietary hardware encryption schemes are assessed by third parties all the time. If you just aren't comfortable with anything but open source, that's fine. But you already rely on plenty of other security systems you can't audit.
- jwr 18y ago
  I don't. And I really do believe that I should be able to audit any security solution I use. I don't understand what you mean by "Proprietary hardware encryption schemes are assessed by third parties all the time". Sounds like corporate speak to me. First, any "proprietary encryption scheme" is rubbish, and second, I should be the one to assess it. My point with the drive encryption solution was that you are told that your data is encrypted, but you have no way of checking it yourself. What if encryption is disabled in your drive? Can you tell? The final output of any encryption solution needs to be independently accessible, so that you can verify if it resembles white noise (which it should, ideally).
  - khafra 18y ago
    If you really want to know, you could always unplug the drive, plug it into another computer, and try your best to recover data--but other people are trying that; people like tptacek, and you could just rely on their assessments.

ks 18y ago

How will this affect data recovery?

mzexfswlkr 18y ago
If you know the passwd then tools going through the drive will not change. If you have to remove the PCB and replace it with one from another drive or you have lost the passwd then you are stuffed. Unless of course the drive maker has built in a backdoor - from past experience of security on PCs the unchangeable security passwd will probably be 'seagate'
ks 18y ago
THIS IS NOT MY COMMENT. I don't know what happened, but there must be a glitch somewhere in the software. I doubt someone has bothered to crack my account, Most likely there is a bug that attributes other posts to my user. This is the second post that is not written by me. Does HN have a place to post bugs?