X series with full disk encryption

I was reading this faq but I'm a little confused

http://www-307.ibm.com/pc/support/site.wss/MIGR-69621.html

If full disk encryption lets you take the drive out and read it from another computer, what is the point?

It later says that setting a HD password is vital. But, can't the password can be circumvented by taking the HD out and moving it to another machine?

I thought FDE was similar to TrueCrypt but in hardware. Is it not so?

(My X came with a Hitachi Travelstar 7K320 with FDE.)

 

The point is that you can't read it on another computer without the encryption key.

No, you still need both the password and the encryption key.

Yes, except an FDE drive does the encryption work, not your CPU.

 

But it says "The encryption key is not system specific. Since the key is maintained by the drive"

And: "The hard drive passwords have no effect on the encryption key. The passwords can safely be changed without risking loss of data."

This is what I think:

1. "The hard drive password prevents unauthorized users from booting the drive and accessing your data" (on that one specific computer in which the BIOS has the HD password)

2. "full disk encryption prevents more sophisticated attacks, such as attempting to retrieve data directly from the drive's platters.' (some sort of high level CIA stuff)

3. Therefore it is still possible to simply take the drive out of the machine, put it in another machine and read all the data. So this is something different than TrueCrypt. Right?

 

Here's another possibility (just like ssh keys):

1) The hard drive has an encryption key, stored on-board, and encoded/decoded in hardware.

2) This encryption key can be passwordless, or it can require a passphrase (aka "password") the first time the drive is powered on. The BIOS can handle this.

3) End result:
(a) You need a password to use the drive on your computer.

(b) Even if you move the drive to another machine, you still need to use the password before the encryption key can be used.

Otherwise, there's no difference between an encrypted drive, and a computer that has a HDD password set in the bios - you need it to boot, but it doesn't protect against drive removal.

 

Well, the FAQ I pointed to says "Since the key is maintained by the drive, it is possible to move the drive to another system still access the data."

And Lenovo ships systems with Vista on it already, so you can't easily change the key after there is already stuff on the drive.

You can add the BIOS menu extension to reset the cryptographic key, but that will erase your HD. And changing the key doesn't help much, since it isn't tied to any pasword (according to the FAQ).

http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-68369

 

Of course you can move the drive to another machine and still access the data - the key is stored on the drive, as the FAQ says. However, you still need a *password* to access the key, so you'll still have to enter that on the machine you move the drive to.

Note that there's a big difference in my explanation between the encryption key, and the password used to access that key. Re-read that FAQ, it's all there.

What encryption algorithm is used, and what is the key strength?
FDE drives use 128- bit AES encryption.

Can I back-up the encryption keys?
[paraphrase] Nope. No way to determine the key. It's for your own security.

Can the encryption key be changed?
[paraphrase] Yes, but it will wipe the drive.

Will changing the Master or User hard drive password change the FDE key?
[paraphrase] No, those don't effect the encryption key.

If the key is on the drive, how do I prevent would-be thieves from stealing the data off my drive?
[paraphrase] If you set a password, it will protect you from moving the drive. Otherwise, you're on your own.

 

Are you just guessing, or are you sure? The system comes without a HD password. How does setting the HD password prevent users from moving the drive? (since it doesn't affect the encryption key on the HD hardware).
I am assuming the HD password sits completely in BIOS and is useful as long as the HD is connected to that 1 machine, but if the drive is moved to another machine without one in its BIOS, what specific mechanism is preventing it from accessing the hd data?

I assume the HD password sits in bios since users without an FDE HD can still set an HD password, or if a machine has multiple HDs in the dock ... what happens when their HDs are moved to other machines? Detailed info would be helpful, I haven't found any from lenovo yet.

 

Well, I haven't used one, so no, I'm not 100% positive, as I haven't tried it. However, I am 99% confident.
Having a password will not protect you from someone stealing your drive - that just takes a couple of screws. However, it will prevent them from acccessing the data on your drive, because *the encrption key is password protected*. The harddrive supports this, and the BIOS is aware of the harddrive. That's why you need the different BIOS, why it will only work on more recent machines (you need a bit of extra hardware), and why most FDE drives are vendor-locked -- the computer and drive need to know about each other.

If you take the drive out and put it in another Lenovo, you'll have to put the harddrive password into the BIOS, otherwise it won't be able to read the drive. If you put it into another computer, you might not be able to access it at all, unless you have the right extra hardware support.

Again, there are *two* things going on here. One is the encryption key, which is hidden in hardware, and you can't access. This key is then password-protected (still in hardware, but it's changeable). In order to access the key, you need the password. If you forget the password, you're screwed. If you move the drive to another machine, you still need the password. In this case, the place in the BIOS is just where you enter the password, so the computer can feed it to the drive. The BIOS knows the difference between a FDE and a regular drive.

Clearer, now?

 

I looked into hardware drive encryption (Hitachi BDE = Bulk Data Encryption / Seagate FDE = Full Drive Encryption) earlier this year. My basic conclusion is that it protects against a very unlikely, esoteric attack: someone disassembling your drive and reading the platters directly on a spin platter. Unless you are working for the CIA, it is extremely unlikely that anyone will go to so much trouble to get your data (IMO).

The troubling thing to me about the encrypting drives is that they are marketed as "Security!" with little to no description of the details. Well, security is hard, and the devil truly is in the details. Without knowing them, we cannot be sure that these hardware-encrypted drives aren't susceptible to very much easier forms of attack. As best I understand it, the encrypting drives control access to their data exactly the same way that non-encrypting drives do: through the ATA passwords. Those are stored on the disk itself (in non-user-accessible area). I've read on the website of at least one data recovery company that previous Seagate drives store the ATA passwords IN CLEARTEXT on the drive, making it nearly trivial for someone who knows what they're doing to retrieve them and access all the drive's data. Has Seagate improved this situation for the hardware-encrypting drives? Who knows! I haven't seen Seagate discuss this vulnerability or any details of how access control is done for the encrypting drives.

And if you use your fingerprint reader to memorize the ATA password?! -- You've just shot yourself in the foot! (Fingerprint reader is easy to defeat--from what I've read, not personal experience.)

Bottom line for me is that I trust the hard drive companies to do hard drives right. NOT SECURITY. That's not their area of expertise. If security is SO IMPORTANT to you that you're willing to pay extra for drive encryption (to prevent very expensive, esoteric attack) then you really need to take pains to consider all the likely methods of attack, and defend against them. Insufficient information is available about the details of the encrypting hard drives to allow this analysis. Conclusion: Do NOT trust them! (Any more than you would ATA passwords on a non-encrypting drive.)

TrueCrypt is (IMO) a far better option, because it is designed and reviewed by security professionals who sweat the details and have a much better chance of getting it right.

Of course, at some point you will realize that Privacy != Security. If you encrypt your data using TrueCrypt and then forget your passphrase / lose your key: say goodbye to your data. It's then *perfectly* private (even from you!) but is hardly "secure"! (More like: vanished.)

Best regards,
Frank

 

I looked into hardware based full disk encryption almost two years ago when Hitachi launched their first BDE (Bulk Data Encryption) drives.

The implementation (as described by Hitachi) seemed solid (see the portion I bolded). Please note that the description below refers to the encryption implementation in Hitachi's first BDE drive generation. I do not know if it is the same in the current generation.

 

That is crucial. Let's hope that Seagate now also encrypts the ATA passwords stored on disk.

 

Thanks for the added information.

So if I set a HD (ATA) password and use a BDE/FDE disk, what is the minimum amout of work a thief would have to do to read the contents of the drive (if they stole it while it was off)?

After googling for a bit I've read about software like "atapwd" or "mhdd" or "hdparm" which give low level access to the ATA password, as well as $50 "harddrive password recovery services".

Do those completely remove the password (it sounds like many HD manufacturers have a "master password" that can reset the user one?) which would make normal HD's readable again, but leaves FDE/BDE HDs unreadable. Perhaps they also allow a brute force attempt at the password (which would be no different than a brute force of a truecrypt disk I guess)?

Am I understanding that correctly? Is there anything else a thief could do? (ie: what is the weakest link in this security chain?)

 

It's impossible to say what the minimum amount of work would be, since there are a number of factors. If I've watched you type your password into the computer, I've got it, and I can just steal the drive (or computer) and have free reign.

As fmyhr points out, some manufacturers store the password in cleartext on the drive, which is my guess on how some of the software you mention works for these. A FDE will almost certainly not do this, since they are designed with security in mind.

Don't believe everything you read on the internet. For example, hdparm is a tool to let you change settings about the drive, including the password. However, it doesn't mean you don't still *need* the password to be able to do so. A quick look seems to imply mhdd and atapwd are similar tools. Also, I'm guessing that many of the articles are referring to non FDE drives.

Yes, there are two passwords, check the original FAQ again, as it mentions them. For FDE, the master password also prevents you from wiping the encryption key (effectively wipes the disk) - it's the difference between preventing someone from accessing or doing any of your data, versus not allowing them to see it, but not stopping them from erasing it all.

The weakest link in the chain is you. If you don't have a good password, it might be possible to brute force (as you say, always a possibility). If you let someone see the password, too bad. If you write the password down and stick it under your keyboard ... well, you deserve what you get.

I'll ask again - What is it that you're trying to accomplish? What are you trying to prevent? What are you afraid of? There are so many things that people can do to your computer/data, being able to *read* it is far lower on my priority list than someone else deleting (or changing) it, or taking it away from me. Or at least that's my take on it.

 

I guess I was referring to some manufacturer's built in master password.
Example: http://www.seagateunlock.com/ "Seagate, TEAMASSEMBLY ..."

My goal is to understand it as well as I can. When products advertise "Security" and "Encryption" like HD's with FDE or BDE, it might just be a marketing catchword but not really provide added security at all. Or it might, but only if certain specific procedures are followed (without a HD password the FDE/BDE is pretty much useless) .

I am trying to understand how security works with an FDE/BDE drive, and compare it to some known quantity that I (partially-)understand (and is better documented) like TrueCrypt, BitLocker, PGPDisk and the rest...

 

1) Read the top of that link: "Recently I have noticed that a lot of people (mostly X-Box users) for some reason want to unlock their drives." So the XBoxes have a default master password to prevent an average Joe from mucking with it. Turns out people figured it out, anyway.
If a drive you buy (or buy with a laptop) comes with a default password, they have to tell you what it is, otherwise you have a crippled computer you can't do whatever you want to. That would not fly.

2) How do you know Lenovo doesn't tell people to set a HD password on the FDEs? You haven't gotten one, so maybe it comes with some extra documentation/labels?

3) You missed my question. I realize that you're trying to understand the security options, and if that's all you're going for, fine. But you seem to be asking with some other goal in mind, and that's what I want to know. Is it purely academic, or are you trying to determine which method would be best for you to use? If so, I'll again ask what your end goal is.

4) It *does* add extra security (over regular drives), as has been explained to you multiple times in this thread. However, as has also been said, the catch is that it often requires a special BIOS and/or hardware in the computer, so you're usually vendor locked. You can take a regular HDD out of your Lenovo and plug it into any other desktop/laptop. With a FDE drive, this is not guaranteed. You can put it in *many* other Lenovos, but there's no guarantee on other manufacturers.

The catch with the software utilities is that all of the encryption is done on the CPU. This makes read/write speed slower, takes up CPU time (so other applications can suffer if you're stressing your machine), etc.

 

My first post said mine came with the Hitachi. No documentation/labels.

To completely understand how it works, without hand waving or presuming that some part of the process works like I expect it to. It would be nice to know where the salt is stored and what hash is used on it with the password, but I don't really care that much. Some independent audit of the process by security pros to validate that it really is secure would be nice.

I do know one thing: Security is hard, and most people get it wrong.

So I read a little more every day and become a little more enlightened.

If the ATA hard drive password system is in the standard ( http://en.wikipedia.org/wiki/Parallel_ATA#HDD_Passwords_and_Security), and the encryption is done in the HD, then I don't see why a special bios would be needed. If the bios doesn't support HD password, then those atapwd/hdparam utils probably still let you mount it. Unless the proces that combines the salt with the pw is in bios rather than in the HD? But I doubt it.

http://www.hitachigst.com/tech/techlib.nsf/techdocs/03E516A3C41738C78625743B005AD957/$file/TS7K320_DS.pdf

But the catch with this BDE drive is that it is limited to SATA 1.5, rather than SATA 3 of the non BDE drives.