6 ms·

Encrypting Your Laptop Like You Mean It

81 points by etiam 12y ago

toddsiegel 12y ago
Are any major computer vendors enabling this by default? Phones are encrypted by default, seems obvious to do the same for laptops and such.
- raesene9 12y ago
  Some phones are encrypted if you add a passcode, but won't be unless you do. Also AFAIK android still isn't by default event when a passcode is set. One of the problems with doing it by default is the consequences of a lost password. On a consumer device (where there's unlikely to be an admin backup password) a lost/forgotten password can result in the user losing all their data. Once people get to the point of storing all personal data off machine (e.g. OneDrive / icloud) it would make more sense to have this kind of thing enabled by default.
ethana 12y ago
Just when I though I know everything about how computer works, here they are talking about freezing ram attack. I didn't even imagine this as a possibility.
- greggyb 12y ago
  This showed up in Burn Notice, though I can't remember the episode. It's cool to see it's real.
- gnud 12y ago
  So, it's obviously hard to defend against a freeze attack when the computer is sleeping - because the key is still needed. But I feel like disk encryption software should, when the computer is being shut down, prepare some random data and write over the encryption key to prevent information leakage in the moments after shutdown. This, combined with some hardware intrusion detection system would help a lot, wouldn't it? Or am I missing something?
  - MichaelGG 12y ago
    There's a neat implementation of AES that uses only registers and never has the key in RAM after boot. I forget the name right now, but it's pretty fucking awesome. IIRC it puts the key into debug registers, then disables access to those registers. It calculates the key schedule on-the-fly for each block it encrypts, and it performs decently with AES-NI. So neither the key, nor any of intermediate pieces, are ever in RAM, just in registers. Edit: Here it is: Tresor: http://www1.informatik.uni-erlangen.de/tresor http://www1.informatik.uni-erlangen.de/tresor
  - Mandatum 12y ago
    I assume the speed of SSD's would be a good counter here. Never sleep, only hibernate or shutdown.
mr337 12y ago
Recommending BitLocker and OSX HD encryption I feel is a diservice to the public. I wouldn't put it past them to already have backdoors built in. Let alone they are both proprietary and not open to public audit. I guess we are suppoed to take their word [1]??? [1] http://mashable.com/2013/09/11/fbi-microsoft-bitlocker-backdoor/ http://mashable.com/2013/09/11/fbi-microsoft-bitlocker-backd...
- dijit 12y ago
  I really get a twisted feeling about people deposing Microsoft Bitlocker or OSX filevault due to potentially being backdoored- yet still running their operating systems, and any third party stuff you give full access to. I mean, I'm not trying to be all tin-foil, but trusting one source is much better than trusting two. (one for live OS security, another for offline data protection)
  - mr337 12y ago
    Who said I was running OS X or MS products? :) I'm not following your 'trusting one source is much better than two'. Care to expand?
    - fossuser 12y ago
      You make the decision to trust some entity 'X' that has some probability of being compromised. If it isn't compromised you're good and if it is you're screwed, but as you add additional entities each introduces an additional individual probability of being 'bad'. There's an argument that it's better to trust one entity entirely in order to have a greater chance of being fully 'safe' rather than split your trust and having a higher chance of being partially compromised since partial compromise is often equivalent to being fully compromised. It's the same idea that leads the Tor network to use entry guard nodes: https://www.torproject.org/docs/faq.html.en#EntryGuards https://www.torproject.org/docs/faq.html.en#EntryGuards
- raesene9 12y ago
  What alternatives would you recommend? Also open to public audit doesn't mean anyone has actually looked at them/assured their security to any degree. the only product that I'm aware of in this category that has received that kind of scrutiny is truecrypt which has been abandonend by its original developers and doesn't have a license that is (AFAIK) conducive to someone else taking over the project.
JustSomeNobody 12y ago
And slow it down like it's 1999.
- raesene9 12y ago
  with hardware support for encryption in CPUs and directly on the drives themselves the hit on performance isn't anything like as bad as it used to be with pure software solutions
nickysielicki 12y ago
I think the best / most secure computer you can use today is a libreboot GM45 thinkpad with FDE, including /boot. The implications of this are big, both in security and in plausable deniability. Look at the case of Jeff Feldman [1], and how having a detectable OS made him liable for the hard disk. If they can't show that the drive contains some kind of OS or that it's not gibberish, you cannot be forced to unencrypt them (don't quote me on this, I'm not entirely sure if I'm speaking the truth.) But if I'm right, having a visible /boot partition is enough to show that there is some kind of OS. With Grub2 written to the board itself, you can get around that. [2] [1]: http://arstechnica.com/tech-policy/2013/05/28/in-reversal-judge-orders-child-porn-suspect-to-decrypt-hard-drives/ http://arstechnica.com/tech-policy/2013/05/28/in-reversal-ju... [2]: http://libreboot.org/docs/gnulinux/encrypted_trisquel.html http://libreboot.org/docs/gnulinux/encrypted_trisquel.html
- raesene9 12y ago
  unfortunately that kind of solution isn't always suitable for mass consumption and the kind of target audience for this article. There is always a trade-off in this kind of case between security and usuability
- greggyb 12y ago
  I don't see how the article you linked to [0] indicates a detectable OS in any way shape or form. Rather, the issue is that if it cannot be shown that you do know the password, then ownership of the drive cannot be determined. Entering the password is equivalent to admitting ownership, and therefore would be self-incriminating. The article indicates that the FBI decrypted one drive and found evidence that it belonged to Feldman: >According to the order (PDF), after devoting “substantial resources” in the case, FBI agents apparently have been able to decrypt one of the drives. The government argued that because it had found “numerous files which constitute child pornography,” “detailed personal financial records and documents belonging to Feldman,” and “dozens of personal photographs of Feldman," Feldman therefore has “access to and control over” the set of drives. Edit: Forgot link. [0]http://arstechnica.com/tech-policy/2013/05/28/in-reversal-judge-orders-child-porn-suspect-to-decrypt-hard-drives/ http://arstechnica.com/tech-policy/2013/05/28/in-reversal-ju...
geographomics 12y ago
For those who use BitLocker: although it is set up to use numeric-only PINs by default, you can configure this to allow any character - which would presumably increase the search space of brute force attacks against the PIN. The relevant Group Policy setting is "Allow enhanced PINs for startup", and can be found in Windows Components → BitLocker Drive Encryption → Operating System Drives.
- MichaelGG 12y ago
  The big question is: is your PIN used only for TPM access? Or is the PIN itself combined after unlocking the TPM? How it should work is that one hash of your PIN is used to unlock the TPM. Then another hash of the PIN is used to mix into the key the TPM provides. That way directly compromising the TPM doesn't provide full access. This is probably strictly obsolete by using a long PIN. But it feels nice to have a TPM, as it's one more piece the attacker needs. If they steal the disk or fuckup the TPM, then the data's gone, even if you reveal your PIN. (ATM, I use Bitlocker, then encrypt my VMs with EFS keyed off a certificate stored on a smartcard. Then I Bitlocker the VM drive itself. It's silly, but that way I get a range of hardware plus brain-stored password. [I don't need it any more, it's just a leftover setup from my BTC experiments.] I also put tamper proof seals all over my laptop, but it requires active work to check them and note the serial number on each one.)
  - geographomics 12y ago
    I wondered that too - apparently in Vista the PIN was only used to authenticate to the TPM and retrieve the volume master key (which in turn protects the key used to actually encrypt the drive). More pleasingly however, in Windows 7 and onwards it is used to encrypt the volume master key as well, in pretty much the way you describe. Microsoft's submissions for FIPS validation have some good detail on this - Windows 7 [see section 7]: http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/140sp1332.pdf http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/1..., others: https://www.google.com/search?q=site:csrc.nist.gov+inurl:140sp+microsoft+bitlocker https://www.google.com/search?q=site:csrc.nist.gov+inurl:140...
bbcbasic 12y ago
The other approach is to not leave anything on your PC that you care about someone else having access to. This could mean keeping a lot of data encrypted online, with keys being remembered (and possibly backed up in a safe at home incase you forget)
- sanqui 12y ago
  This would at minimum leave your cache exposed...
SEJeff 12y ago
I'm a Linux desktop/laptop user and just wanted to point out that LUKs encryption is built right into the RHEL / Fedora installer and works like a champ.
lawl 12y ago
> Unlike in Windows and Mac OS X, you can only encrypt your disk when you first install Linux. That is obviously simply not true. There is no user friendly GUI way to do it, but it is definitly doable, and that's what they should have written. Also, recommending BitLocker, and not having the main guide for something more user friendly and open source?
- raesene9 12y ago
  out of curiousity, what would you recommend as a user friendly open source disk encryption product in place of Bitlocker?
  - lawl 12y ago
    Well, back when I used windows TrueCrypt was still a thing. Depending on your threat model, probably still TC though. If your threat model is the NSA, I'd advise you to not use windows anyways. Plus, if it does turn out TC has a major flaw, someone abusing it might make a noise. And as far as I'm aware the TC audit also hasn't found anything serious so far. If you aren't betting your life on it, I think you're still fine with TrueCrypt, Plus, encrypting your full drive with it is something my mother could do. Next, next, next done, at least that's how I remember it. Edit: Thinking about it, this is firstlook.org, maybe they know something we don't, but recommending BitLocker over TC sill seems like a stretch.
    - nhayden 12y ago
      TrueCrypt doesn't support EUFI which pretty much all laptops use these days.
    - dheera 12y ago
      Thing about TrueCrypt is that it was built for a specific purpose. Just having the app installed is like walking around wearing lockpicks and saying that you don't pick locks, you're just wearing them for decoration. If it was called 'ext4' (yes, deliberately pick a conflicting name with something that already exists in widespread use, and provide a drop-in replacement) it might be better. This would be the equivalent of walking around with paper clips instead, which has much better plausible deniability. Bonus points if it could be engineered to actually mount as an ext4 volume if someone actually tried.
paulannesley 12y ago
> But unfortunately, laptops have ports that have direct memory access, or DMA, including FireWire, USB, and others. USB doesn't exposes DMA. “Examples of connections that may allow DMA in some exploitable form include FireWire, ExpressCard, Thunderbolt, PCI and PCI Express.” – http://en.wikipedia.org/wiki/DMA_attack http://en.wikipedia.org/wiki/DMA_attack
- paulannesley 12y ago
  Related from 2006: Schneier on Security — Hacking Computers Over USB https://www.schneier.com/blog/archives/2006/06/hacking_compute.html https://www.schneier.com/blog/archives/2006/06/hacking_compu... The block-quote incorrectly mentions DMA over USB, but the described attack uses Windows AutoRun. The comments discuss a demonstrated FireWire iPod based DMA attack, and that USB doesn't expose DMA.
barrkel 12y ago
If you're crossing borders with electronic stuff, simply don't bring anything personal. Access it remotely. You'll only be out hardware should the hardware be confiscated, and you'll have no big privacy breach should you have to boot the machine to show to customs. Clear cache / cookies beforehand, or use the browser in a mode that clears on shutdown. Use suspend / hibernate when not crossing borders, but do a proper shutdown when going through borders. Carrying valuable data around then trying to protect it by encrypting it, while simultaneously going through borders, is just asking for trouble IMO. You'll look like a complete freak should you be picked on, very suspicious.
- jmnicolas 12y ago
  Well it's probably easier and cost effective for "them" to access your remote data (and they probably already have with their dragnet surveillance programs) than to decrypt your laptop.
deleted 12y ago
[deleted]
zaroth 12y ago
How's OPAL support looking on Linux these days? Last time I looked all I could find was: https://github.com/r0m30/msed https://github.com/r0m30/msed
evolve2k 12y ago
What are people thoughts on where to keep your encryption password? Is it fine just to keep it in lastpass/one pass?
rainwolf 12y ago
Note that with FileVault on, backups are not automatically encrypted. Time Machine is a smooth backup experience, but should be encrypted as well.

81 points by etiam 12y ago

Are any major computer vendors enabling this by default? Phones are encrypted by default, seems obvious to do the same for laptops and such.

raesene9 12y ago
Some phones are encrypted if you add a passcode, but won't be unless you do. Also AFAIK android still isn't by default event when a passcode is set. One of the problems with doing it by default is the consequences of a lost password. On a consumer device (where there's unlikely to be an admin backup password) a lost/forgotten password can result in the user losing all their data. Once people get to the point of storing all personal data off machine (e.g. OneDrive / icloud) it would make more sense to have this kind of thing enabled by default.

ethana 12y ago

Just when I though I know everything about how computer works, here they are talking about freezing ram attack. I didn't even imagine this as a possibility.

greggyb 12y ago
This showed up in Burn Notice, though I can't remember the episode. It's cool to see it's real.
gnud 12y ago
So, it's obviously hard to defend against a freeze attack when the computer is sleeping - because the key is still needed. But I feel like disk encryption software should, when the computer is being shut down, prepare some random data and write over the encryption key to prevent information leakage in the moments after shutdown. This, combined with some hardware intrusion detection system would help a lot, wouldn't it? Or am I missing something?
- MichaelGG 12y ago
  There's a neat implementation of AES that uses only registers and never has the key in RAM after boot. I forget the name right now, but it's pretty fucking awesome. IIRC it puts the key into debug registers, then disables access to those registers. It calculates the key schedule on-the-fly for each block it encrypts, and it performs decently with AES-NI. So neither the key, nor any of intermediate pieces, are ever in RAM, just in registers. Edit: Here it is: Tresor: http://www1.informatik.uni-erlangen.de/tresor http://www1.informatik.uni-erlangen.de/tresor
- Mandatum 12y ago
  I assume the speed of SSD's would be a good counter here. Never sleep, only hibernate or shutdown.

mr337 12y ago

Recommending BitLocker and OSX HD encryption I feel is a diservice to the public. I wouldn't put it past them to already have backdoors built in. Let alone they are both proprietary and not open to public audit. I guess we are suppoed to take their word [1]??? [1] http://mashable.com/2013/09/11/fbi-microsoft-bitlocker-backdoor/ http://mashable.com/2013/09/11/fbi-microsoft-bitlocker-backd...

dijit 12y ago
I really get a twisted feeling about people deposing Microsoft Bitlocker or OSX filevault due to potentially being backdoored- yet still running their operating systems, and any third party stuff you give full access to. I mean, I'm not trying to be all tin-foil, but trusting one source is much better than trusting two. (one for live OS security, another for offline data protection)
- mr337 12y ago
  Who said I was running OS X or MS products? :) I'm not following your 'trusting one source is much better than two'. Care to expand?
  - fossuser 12y ago
    You make the decision to trust some entity 'X' that has some probability of being compromised. If it isn't compromised you're good and if it is you're screwed, but as you add additional entities each introduces an additional individual probability of being 'bad'. There's an argument that it's better to trust one entity entirely in order to have a greater chance of being fully 'safe' rather than split your trust and having a higher chance of being partially compromised since partial compromise is often equivalent to being fully compromised. It's the same idea that leads the Tor network to use entry guard nodes: https://www.torproject.org/docs/faq.html.en#EntryGuards https://www.torproject.org/docs/faq.html.en#EntryGuards
raesene9 12y ago
What alternatives would you recommend? Also open to public audit doesn't mean anyone has actually looked at them/assured their security to any degree. the only product that I'm aware of in this category that has received that kind of scrutiny is truecrypt which has been abandonend by its original developers and doesn't have a license that is (AFAIK) conducive to someone else taking over the project.

JustSomeNobody 12y ago

And slow it down like it's 1999.

raesene9 12y ago
with hardware support for encryption in CPUs and directly on the drives themselves the hit on performance isn't anything like as bad as it used to be with pure software solutions

nickysielicki 12y ago

I think the best / most secure computer you can use today is a libreboot GM45 thinkpad with FDE, including /boot. The implications of this are big, both in security and in plausable deniability. Look at the case of Jeff Feldman [1], and how having a detectable OS made him liable for the hard disk. If they can't show that the drive contains some kind of OS or that it's not gibberish, you cannot be forced to unencrypt them (don't quote me on this, I'm not entirely sure if I'm speaking the truth.) But if I'm right, having a visible /boot partition is enough to show that there is some kind of OS. With Grub2 written to the board itself, you can get around that. [2] [1]: http://arstechnica.com/tech-policy/2013/05/28/in-reversal-judge-orders-child-porn-suspect-to-decrypt-hard-drives/ http://arstechnica.com/tech-policy/2013/05/28/in-reversal-ju... [2]: http://libreboot.org/docs/gnulinux/encrypted_trisquel.html http://libreboot.org/docs/gnulinux/encrypted_trisquel.html

raesene9 12y ago
unfortunately that kind of solution isn't always suitable for mass consumption and the kind of target audience for this article. There is always a trade-off in this kind of case between security and usuability
greggyb 12y ago
I don't see how the article you linked to [0] indicates a detectable OS in any way shape or form. Rather, the issue is that if it cannot be shown that you do know the password, then ownership of the drive cannot be determined. Entering the password is equivalent to admitting ownership, and therefore would be self-incriminating. The article indicates that the FBI decrypted one drive and found evidence that it belonged to Feldman: >According to the order (PDF), after devoting “substantial resources” in the case, FBI agents apparently have been able to decrypt one of the drives. The government argued that because it had found “numerous files which constitute child pornography,” “detailed personal financial records and documents belonging to Feldman,” and “dozens of personal photographs of Feldman," Feldman therefore has “access to and control over” the set of drives. Edit: Forgot link. [0]http://arstechnica.com/tech-policy/2013/05/28/in-reversal-judge-orders-child-porn-suspect-to-decrypt-hard-drives/ http://arstechnica.com/tech-policy/2013/05/28/in-reversal-ju...

geographomics 12y ago

For those who use BitLocker: although it is set up to use numeric-only PINs by default, you can configure this to allow any character - which would presumably increase the search space of brute force attacks against the PIN. The relevant Group Policy setting is "Allow enhanced PINs for startup", and can be found in Windows Components → BitLocker Drive Encryption → Operating System Drives.

MichaelGG 12y ago
The big question is: is your PIN used only for TPM access? Or is the PIN itself combined after unlocking the TPM? How it should work is that one hash of your PIN is used to unlock the TPM. Then another hash of the PIN is used to mix into the key the TPM provides. That way directly compromising the TPM doesn't provide full access. This is probably strictly obsolete by using a long PIN. But it feels nice to have a TPM, as it's one more piece the attacker needs. If they steal the disk or fuckup the TPM, then the data's gone, even if you reveal your PIN. (ATM, I use Bitlocker, then encrypt my VMs with EFS keyed off a certificate stored on a smartcard. Then I Bitlocker the VM drive itself. It's silly, but that way I get a range of hardware plus brain-stored password. [I don't need it any more, it's just a leftover setup from my BTC experiments.] I also put tamper proof seals all over my laptop, but it requires active work to check them and note the serial number on each one.)
- geographomics 12y ago
  I wondered that too - apparently in Vista the PIN was only used to authenticate to the TPM and retrieve the volume master key (which in turn protects the key used to actually encrypt the drive). More pleasingly however, in Windows 7 and onwards it is used to encrypt the volume master key as well, in pretty much the way you describe. Microsoft's submissions for FIPS validation have some good detail on this - Windows 7 [see section 7]: http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/140sp1332.pdf http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/1..., others: https://www.google.com/search?q=site:csrc.nist.gov+inurl:140sp+microsoft+bitlocker https://www.google.com/search?q=site:csrc.nist.gov+inurl:140...

bbcbasic 12y ago

The other approach is to not leave anything on your PC that you care about someone else having access to. This could mean keeping a lot of data encrypted online, with keys being remembered (and possibly backed up in a safe at home incase you forget)

sanqui 12y ago
This would at minimum leave your cache exposed...

SEJeff 12y ago

I'm a Linux desktop/laptop user and just wanted to point out that LUKs encryption is built right into the RHEL / Fedora installer and works like a champ.

lawl 12y ago

> Unlike in Windows and Mac OS X, you can only encrypt your disk when you first install Linux. That is obviously simply not true. There is no user friendly GUI way to do it, but it is definitly doable, and that's what they should have written. Also, recommending BitLocker, and not having the main guide for something more user friendly and open source?

raesene9 12y ago
out of curiousity, what would you recommend as a user friendly open source disk encryption product in place of Bitlocker?
- lawl 12y ago
  Well, back when I used windows TrueCrypt was still a thing. Depending on your threat model, probably still TC though. If your threat model is the NSA, I'd advise you to not use windows anyways. Plus, if it does turn out TC has a major flaw, someone abusing it might make a noise. And as far as I'm aware the TC audit also hasn't found anything serious so far. If you aren't betting your life on it, I think you're still fine with TrueCrypt, Plus, encrypting your full drive with it is something my mother could do. Next, next, next done, at least that's how I remember it. Edit: Thinking about it, this is firstlook.org, maybe they know something we don't, but recommending BitLocker over TC sill seems like a stretch.
  - nhayden 12y ago
    TrueCrypt doesn't support EUFI which pretty much all laptops use these days.
  - dheera 12y ago
    Thing about TrueCrypt is that it was built for a specific purpose. Just having the app installed is like walking around wearing lockpicks and saying that you don't pick locks, you're just wearing them for decoration. If it was called 'ext4' (yes, deliberately pick a conflicting name with something that already exists in widespread use, and provide a drop-in replacement) it might be better. This would be the equivalent of walking around with paper clips instead, which has much better plausible deniability. Bonus points if it could be engineered to actually mount as an ext4 volume if someone actually tried.

paulannesley 12y ago

> But unfortunately, laptops have ports that have direct memory access, or DMA, including FireWire, USB, and others. USB doesn't exposes DMA. “Examples of connections that may allow DMA in some exploitable form include FireWire, ExpressCard, Thunderbolt, PCI and PCI Express.” – http://en.wikipedia.org/wiki/DMA_attack http://en.wikipedia.org/wiki/DMA_attack

paulannesley 12y ago
Related from 2006: Schneier on Security — Hacking Computers Over USB https://www.schneier.com/blog/archives/2006/06/hacking_compute.html https://www.schneier.com/blog/archives/2006/06/hacking_compu... The block-quote incorrectly mentions DMA over USB, but the described attack uses Windows AutoRun. The comments discuss a demonstrated FireWire iPod based DMA attack, and that USB doesn't expose DMA.

barrkel 12y ago

If you're crossing borders with electronic stuff, simply don't bring anything personal. Access it remotely. You'll only be out hardware should the hardware be confiscated, and you'll have no big privacy breach should you have to boot the machine to show to customs. Clear cache / cookies beforehand, or use the browser in a mode that clears on shutdown. Use suspend / hibernate when not crossing borders, but do a proper shutdown when going through borders. Carrying valuable data around then trying to protect it by encrypting it, while simultaneously going through borders, is just asking for trouble IMO. You'll look like a complete freak should you be picked on, very suspicious.

jmnicolas 12y ago
Well it's probably easier and cost effective for "them" to access your remote data (and they probably already have with their dragnet surveillance programs) than to decrypt your laptop.

deleted 12y ago

[deleted]

zaroth 12y ago

How's OPAL support looking on Linux these days? Last time I looked all I could find was: https://github.com/r0m30/msed https://github.com/r0m30/msed

evolve2k 12y ago

What are people thoughts on where to keep your encryption password? Is it fine just to keep it in lastpass/one pass?

rainwolf 12y ago

Note that with FileVault on, backups are not automatically encrypted. Time Machine is a smooth backup experience, but should be encrypted as well.