EncFS - an Encrypted Filesystem
EncFS provides an encrypted filesystem in user-space. It runs in userspace, using the FUSE library for the filesystem interface. EncFS is open source software, licensed under the LGPL.
EncFS is now over 15 years old (first release in 2003). It was written because older NFS and kernel-based encrypted filesystems such as CFS had not kept pace with Linux development. When FUSE became available, I wrote a CFS replacement for my own use and released the first version to Open Source in 2003.
EncFS encrypts individual files, by translating all requests for the virtual EncFS filesystem into the equivalent encrypted operations on the raw filesystem.
For more info, see:
Over the last 15 years, a number of good alternatives have grown up. Computing power has increased to the point where it is reasonable to encrypt the entire filesystem of personal computers (and even mobile phones!). On Linux, ecryptfs provides a nice dynamically mountable encrypted home directory, and is well integrated in distributions I use, such as Ubuntu.
EncFS has been dormant for a while. I've started cleaning up in order to try and provide a better base for a version 2, but whether EncFS flowers again depends upon community interest. In order to make it easier for anyone to contribute, it is moving a new home on GitHub (2014). Since then project has been updated a few times thanks to several contributors, so if you're interested in EncFS, please dive in!
EncFS has a few features still not found anywhere else (as of Dec 2014) that may be interesting to you:
encfs --reverse provides an encrypted view of an unencrypted folder. This enables encrypted remote backups using standard tools like rsync.
Fast on classical HDDs
EncFS is typically much faster than ecryptfs for stat()-heavy workloads when the backing device is a classical hard disk. This is because ecryptfs has to to read each file header to determine the file size - EncFS does not. This is one additional seek for each stat. See PERFORMANCE.md for detailed benchmarks on HDD, SSD and ramdisk.
Works on top of network filesystems
EncFS works on network file systems (NFS, CIFS...), while ecryptfs is known to still have problems.
The master branch contains the latest stable codebase. This is where bug fixes and improvments should go.
The dev branch contains experimental work, some of which may be back-ported to the master branch when it is stable. The dev branch is not stable, and there is no guarantee of backward compatibility between changes.
How about a nice email instead?
EncFS works on Cygwin, there are also some Windows ports.
See the wiki for additional info.
What settings should I use for Dropbox?
Use standard mode. There have been reports of a pathological interaction of paranoia mode with Dropbox' rename detection. The problem seems to be with
External IV chaining, which is not active in standard mode.