I'd love to use Ubuntu One or Dropbox features, like file storage and so on, but I don't want anyone else to access my data, USA Patriot act etc.. I want things to be encrypted so that the only place where info is decrypted is only my devices. Is that possible with Ubuntu One or Dropbox?
Yes it is possible. The best way to archive this with a per file encryption is with encfs:
The general principle is that you have a (optionally hidden) encrypted folder inside UbuntuOne/Dropbox where your files are stored, but you access them though another folder, where the decrypted files are shown. Any File you add to the decrypted folder will be encrypted and put into the encrypted folder:
Decrypted folder ←encfs→ Encrypted Folder (inside UbuntuOne/Dropbox)
On another computer the encrypted folder is synced by UbuntuOne/Dropbox and can also be decrypted on the fly.
Setting up the Drive on the first computer:
You should now have your encrypted drive mounted (it will be displayed like a mounted usb-drive)
Importing the drive on other computers:
Cross Platform compatibility:
The only good way to do this is to first encrypt the files locally, then move them to the Ubuntu One folder. If you make an encrypted partition or container and then choose to sync that with Ubuntu One, you risk syncing the unencrypted data. See here for one approach using encFS. It has it's limitations though.
An alternative is SpiderOak, which works like Ubuntu One but encrypts everything before it leaves your machine. They claim they have no way to recover your data if you forget your password, and it even has two-factor authentication. Last I tried it, it would slow down my machine for several minutes after booting while it scanned my drive, but this may have been fixed by now. Also, it's 2GB free vs Ubuntu One's free 5GB.
This is a great question though, and I hope Ubuntu One can have very robust encryption for files stored online soon. Many people have already requested the feature. This is another Ask Ubuntu post detailing some of the issues you raise.
You could possibly make use of EncFS (http://www.arg0.net/encfs). Use the Ubuntu One directory to store the encrypted file system, while mounting it somewhere else. For example, using the following setup.
This however will make the number of files, directory and file structure, and their sizes visible, so it's not an ultimate solution.
I can propose you the Wuala service here: http://www.wuala.com/en as an alternative to Spideroak. Almost same functionalities.
But, if you really want to control the encryption yourself, I can propose you to use Ubuntu One and Déjà-Dup (backup tool) together. You use the server space of Ubuntu One for your data, but you upload the data through Déjà-Dup using a password. Déjà-Dup will encrypt the data with your password. I think this is the best solution: simple and secure.
Thank you very mutch !
I tried SpiderOak.
Pros: "Zero knowledge" concept built in from the ground, exactly what I was looking for.
Cons: Closed source client. I trust open source more, when it comes to security.
I chose to go with UbuntuOne + EncFs, since encryption layer is open source.
Still would very appreciate if UbuntuOne would implement "Zero Knowledge" concept out of the box.
Now I'm using SSHFS against own server to access large files like photo / video collection.
pros: No need to duplicate every file on every computer.
cons: Useless on slow network connections or when offline.
And I use GIT + GITCOLA for document registry.
pros: Can work offline.
cons: Doesn't work well on binary files above 1 GB.
And I use UbuntuOne + EncFS for a few gigabytes of fast changing and temporary files, like Desktop directory. This way I can conveniently switch computers and continue working on the same in-progress files, even sometimes offline and without quickly growing GIT repository.
You can also use truecrypt.
Below is a short summary of how can you use truecrypt (sources for detailed instructions are provided below):
Now, you can upload this volume container to your Ubuntu One account.
Sources and further information:
This answer was not intended to be a comparison but below I'm mentioning advantages/disadvantages of using truecrypt for reference.
The advantages of using truecrypt (over encfs) are as follows:
The disadvantages are:
You might want to take a look at the Gnome Encfs Manager project.
It implements an easy GUI way to organize one or multiple EncFS volumes (which you then can sync via Ubuntu One, Dropbox and similar services; maybe WebDAV also works).
Look at Uli's answer for the details:
I think, it's the way you have to think the least. Plus, it is open source.
Thank you for a lot of great answers! But Ubuntu File storage is now dead. I use https://syncthing.net/ now.
There is a relatively new open source project called Cryfs which was designed for encrypting your Dropbox (or other cloud storage). Disclaimer: I'm one of the developers.
It was built mainly because all existing encrypted file systems have their disadvantages when used with cloud storage.
Furthermore, CryFS not only encrypts your file contents, but also file sizes, metadata and directory structure, which is not true for the other tools except VeraCrypt.
Not encrypting your file sizes and directory structure can give an attacker more information than you'd like to give them. A standard example is a file system with a lot of folders, ~20 files each and each file ~3MB, which is easily recognized to be a music CD collection, even if encrypted. Another example is storing a certain set of known files (say a Windows DVD). By looking at the directory structure and file sizes, someone having access to the encrypted files can easily figure out whether your file system contains it or not.