Is an encrypted home more likely to get corrupted?

1

As far as I know, if you change a single bit in an encrypted file (or an email, or anything else) the result of the decryption will be totally different.

I want to encrypt my ~ directory, but I'm worried about losing everything because of a single corrupted bit.

Any thoughts?

Note: I'm using Ubuntu 12, which asks me if I want to encrypt home during the installation.

Note 2: To the readers: I accepted an answer, but you must read all the comments to get the whole picture.

HappyDeveloper

Posted 2012-05-23T23:29:39.007

Reputation: 1 393

Of course you wouldn't lose everything, because you have a backup...right? ...right? – rob – 2012-05-23T23:39:49.603

@rob Of course =p... Sort of. I'm not used to configuring automatic backups yet. I only have the most important things on Ubuntu One. – HappyDeveloper – 2012-05-23T23:45:43.823

If you have (good, tested) backups, there's no risk, since the same effect can render unencrypted data corrupt as well. – None – 2012-05-24T00:25:52.703

1@HappyDeveloper CrashPlan is a pretty slick cross-platform backup program. You can either pay to back up online, or for free you can target as many of your own or friends' computers as you want. As far as encrypting your home directory, I've done it before and haven't had any problems. – rob – 2012-05-24T00:55:38.947

Actually, with encryption, if you lose one bit you only lose the logical sector in which it resides -- you don't lose the entire drive. (If it were otherwise you'd have to read/write the entire disk to change one byte.) Of course, that one sector could be critical to the whole system, but what else is new. – Daniel R Hicks – 2012-05-24T01:49:02.490

@RandolphWest If I have an unencrypted message, and change 1 bit, a character could be changed or something. But if it is encrypted, the whole message would be changed, as encryption algorithms are designed to behave that way. But DanH clarified that it is separated by sectors when done on files (if I didn't get it wrong) – HappyDeveloper – 2012-05-24T02:18:53.197

I meant what DanH said, but he was more eloquent. – None – 2012-05-24T03:21:55.260

2@HappyDeveloper -- When encryption is done on a FULL DISK it's done by "logical sector" (which may be larger or smaller than the physical disk sectors). When encryption is done on INDIVIDUAL FILES it's generally done on the file as a whole. – Daniel R Hicks – 2012-05-24T12:01:13.033

Answers

1

I believe that Ubuntu's 'encrypted home' feature actually encrypts the individual files and stores them in another directory (~/.Private), as opposed to creating a single encrypted volume. In that case, losing a single file wouldn't cost you your entire home directory.

FWIW I've been using full-disk encryption (so the whole root partition has to be unlocked before I can access any of it) for several years on multiple computers, running both Ubuntu and Debian without any issues (yet....).

user66178

Posted 2012-05-23T23:29:39.007

Reputation:

From the article: "Ubuntu 9.04 extended the Encrypted Private Directory feature to cover entire home directories". – HappyDeveloper – 2012-05-24T02:11:53.657

Asked: 2012-05-23T23:29:39.007

Viewed: 214 times

Active: 2017-04-09T09:50:56.730