Comment by Niten | Hacker News Reader

Comment by Niten | Hacker News Reader

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> OS X equivalent is encrypted disk images and FileVault

Calling FileVault an "equivalent" of BitLocker is too generous. BitLocker provides several important things currently lacking from OS X's built in disk encryption facilities:

* Strong encryption: If you use FileVault, you're essentially gambling that your hypothetical attacker can't break a 1024-bit RSA key. That isn't such a good bet these days.

* Trusted boot path in conjunction with a TPM; defense against the "evil maid" attack

* Support for full disk encryption, not merely encryption of home directories

* Enterprise key management and recovery, so that full disk encryption can conceivably be used within a large organization

You'll want to buy PGP or similar if you're on a Mac and you want good disk encryption. (But that still won't give you anything like BitLocker's boot path verification.)

But yeah, the whole parental controls thing is not only a moot point (didn't OS X actually have that first?), but pretty much irrelevant to security in the sense intended in this discussion...

Apple can't use a TPM without people going apoplectic, even now years later. After the first couple shitstorms when the Intel Developer Preview Mac and a few other early models had TPMs, they just stopped including them with any of their hardware, despite (or perhaps because) they're essentially the only outfit that could pull that off.

Only a few models had them, and Apple doesn't like to ship features like that, especially with the way they'd get shat on over it.

I think your argument about 1024-bit RSA being too weak is pretty much nonsense, and nothing defends against the "evil maid" attack, which kind of misses the point of full disk encryption anyways.

TPM support would be nice, though.

You're wrong on both counts. Even back in 2007, NIST deemed 1024-bit RSA too weak:

http://csrc.nist.gov/publications/nistpubs/800-57/sp800-57-P...

And BitLocker's trusted boot path does defend against the evil maid attack:

http://theinvisiblethings.blogspot.com/2009/01/why-do-i-miss...

Even if you want to make some semantic argument that this doesn't strictly fall under the mantle of "disk encryption", it still proves the point that FileVault is no substitute for BitLocker.

I'm wrong on neither count. The likelihood that anyone's disk encryption is going to be broken by a brute force attack on an RSA key of any size is nil. There remain attacks on Bitlocker regardless of whether it boots from a static trusted root. And, again: the whole notion of "evil maid" attacks does miss the point of disk encryption; if you lose control of your computer, it's no longer trustworthy no matter what.

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