Take the 2-minute tour ×
Information Security Stack Exchange is a question and answer site for Information security professionals. It's 100% free, no registration required.

i'd like to know if Truecrypt is a reliable software for filesystem encryption, at the level of pgp as security level, and if it suitable to work with files that are generate via web browser, so through server side o client side languages, for keeping encrypted theses files on a filesystem.

Moreover using a software like this, would you keep a security not encrypted copy of your private data, for example on a dvd or a usb hard disk, in case of software failure or error, or you would only rely on the software ?

How much is Truecrypt reliable ? Can it be cause of data losses, due to a malfunction, I mean not due to a forgotten password, but to an internal error of the software ?

Thanks

share|improve this question
    
A bit vague first question. Truecrypt encrypts data with an algorithm you can choose and a password or keyfile you can set. What does a browser have to do with this? Anything transmitted over HTTP can be read and tampered with, I guess you know that. And what do server-side languages have to do with the generation of files in a browser.. and then have something to do with security? –  Luc Oct 19 '12 at 23:49
add comment

1 Answer

up vote 2 down vote accepted

As I've commented, I find your first question a bit vague, so I'll go on with the rest:

Moreover using a software like this, would you keep a security not encrypted copy of your private data, for example on a dvd or a usb hard disk, in case of software failure or error, or you would only rely on the software?

How much is Truecrypt reliable ? Can it be cause of data losses, due to a malfunction, I mean not due to a forgotten password, but to an internal error of the software ?

Truecrypt is widely used, but you can never guarantee that it's completely free of bugs. For example, when it's in the middle of a write operation and the power fails, the disk won't complete the write, possibly leaving the file corrupt. Not Truecrypt's fault, but it can happen.

So yes, if the data is important to me, I would always keep a backup. You can keep an unencrypted backup, but what's wrong with storing an older version of the encrypted file? (Truecrypt stores the encrypted virtual drive as a single file.) Mount the file, read/modify it, and unmount it when you're done, just like you normally would. Then, test if you can decrypt the saved file (so that you know it's stored correctly), and copy the file. That makes sure you won't loose (much) data because of something caused by Truecrypt itself. The more regularly you copy the file, the less work you could loose of course. Just like with normal backups.

Then there are issues like drive crashes, the chance on fire... So an off-site redundant backup would best protect your data (all the wile keeping it encrypted). Just like with normal backups.

share|improve this answer
    
Remember to backup key files and keep them safe too. –  ewanm89 Oct 20 '12 at 1:26
1  
I don't think writes during a power failure are likely to cause much corruption. When using the XTS block cipher mode, a single corrupt block will cause the next block to be corrupt too, but nothing more after that. Furthermore, most disks and disk drivers are designed to be transactional - i.e. a write will only ever be written or not written, never part-written. At worst this means you'll have a single corrupt block, where the second block hasn't been updated to reflect changes in the first. As such, the corruption would be limited to a single 32 byte block. Easily recoverable in many cases. –  Polynomial Oct 20 '12 at 15:55
    
Thanks so much for the explanation to both of you.@Luc the first question was about the possibility to write directly in the encrypted virtual drive, with the browser, for example using ActiveX controls, or by executing a php script that creates a local file into the server folders –  webose Oct 20 '12 at 22:39
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.