Password protect External Hard Disk that works both in Windows and in Ubuntu

Question

I followed "possible duplicates" of my question but none of them cover full criteria that I need.

I'm having a Seagate FreeAgent GoFlex 500 GB Ext. Drive, Seagate provided me with a backup and encryption software but I assume that it is Windows only. Now, my laptop is dual booted with Windows 7 and Ubuntu. So I want a security mechanism to protect my drive (and data in there) such that:

• It works with Windows 7 as well as Ubuntu (11.04).
• Requires a password to access the drive, being any of the two platform.
• If inevitable, it may encrypt the data on the drive but not at the cost of slow I/O performance as my drive has mostly multimedia files stored in it, so I want fast access to the files even if it is encrypted.
• It should prevent formatting or re-partitioning or any such task on the drive to unauthenticated user.

I know my requirements are higher especially because I want them to be cross-platform but I really don't want anyone to access my precious media collection without my permission. I considered BitLocker but I guess it won't work in Ubuntu as it works with Windows. Also, I don't know if it is a myth that: A large file takes same long time to get encrypted, and if it is true than that would be a troublesome since my drive has lot of data which might take couple of hours to get encrypted.

If possible, I'd prefer to have an open source solution, just in case I need to tweak it to my requirements.

Thanks.

Solution

TrueCrypt comes to mind. It's open source and available for multiple systems. It won't meet your 4th criterion, but then nothing will.

Even if you can prevent someone from reformatting a drive you can't stop them from hitting it with a hammer.

Comments

[Admin]

There was a service I had come accross that could encrypt the whole volume and create a mountable volume.

[Kushal]

Obviously, I can't give my drive a z-grade security, but like BitLocker prevents to boot from the encrypted drive (if user really wants) such a strong security would be great, otherwise, TrueCrypt is a viable option.