I don't trust Dropbox to keep my files secure. In fact, the same goes for all the other file clouds. What I'd like is a easy and cross platform means of encrypting files that I add and read from Dropbox. I'd love to be able to use Dropbox as if I'm mounting an encrypted partition. In other words, so I don't need to unencrypt a file to open it, or grep through it. And when I add or edit a file, it is automatically encrypted before being saved to Dropbox's server.
There is tool by Stefan Küng called CryptSync that does almost exactly what you are describing there. You can find it here.
The developer is the same trusted developer who created the hugely popular SVN client "TortoiseSVN" and many other tools, so I would have no problem trusting it. I think the tool uses the 7z implementation of AES encryption.
From what I can see the current downloadable client is for the Windows platform only but the source code is open source and written in C±± (cross platform portability) so you can modify it as needed and compile it on your own.
Edit: I recently also discovered Boxcryptor which is cross platform but not open source or free (quite expensive in fact).
There are few simple steps:
- Create an encrypted directory in Dropbox folder (or select whole Dropbox folder) with encfs
- Mount that directory to another place (eg. next to the Dropbox folder)
- Add a file to mounted directory
- Encfs automatically encrypts the file and Dropbox service will upload it
I hope this dialog continues as my research on the topic isn't done yet. CryptSync is a basic solution that can solve the issue as can Toucan. I have been researching on this for over 60 hours and have loaded and tested dozens of programs in a virtual environment.
My requirements were a little more strict. 1.) Encrypt on the fly to a cloud box. (Must be a virtual "on PC" folder like Dropbox ... preferably a Cloud aggregator with many Clouds for size and redundancy. 2.) Unencrypt on the fly on the other side whether it be laptop or other PC. 3.) Have VSS capability for image snapshots ... this is where it gets tough. 4.) Be very very fast with a smallish footprint versus a sluggish, processor and memory hog like Dropbox. ... tougher still. 5.) I have married Radmin (remote desktop) to zeroTierOne for a very snappy total console from all my PC's and I use TrueCrypt (Yes it is still super duper NSA unbreakable safe) ... I use a TrueCrypt encrypted drive with an encrypted core drive inside of that for all the essentials like Bitcoin Wallets, passwords, codes etc. Which are also encrypted inside of all that as well.
Since many of my PC's are mostly on most of the time I think BittorrentSync might be the solution by creating "fast load swarms" at 7 times the speed of Dropbox and a strait P2P cloud. (This with perhaps a MultCloud redundancy ... might be brilliant.)
BTW - zeroTierOne can be used to create cloud backplanes if one wants to create their own cloudamongus
Duplicati may also be a true contender with any combo of the above. Waiting for their Beta to reach release stage though.
The problem with doubling the programs like mentioned above is double footprint, double risk that the program will die on the vine into a non-supported product.