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[](https://nuetzlich.net/gocryptfs/) [](https://travis-ci.org/rfjakob/gocryptfs) 
==============
An encrypted overlay filesystem written in Go.
Official website: https://nuetzlich.net/gocryptfs
gocryptfs is built on top the excellent
[go-fuse](https://github.com/hanwen/go-fuse) FUSE library and its
LoopbackFileSystem API.
This project was inspired by EncFS and strives to fix its security
issues while providing good performance
([benchmarks](https://nuetzlich.net/gocryptfs/comparison/#performance)).
For details on the security of gocryptfs see the
[Security](https://nuetzlich.net/gocryptfs/security/) design document.
All tags from v0.4 onward are signed by the *gocryptfs signing key*.
Please check [Signed Releases](https://nuetzlich.net/gocryptfs/releases/) for
details.
Current Status
--------------
gocryptfs is a young project. While bugs in any software can cause issues,
bugs in encryption software can cause catastrophic data loss. Keep a backup
of your gocryptfs filesystem *and* store a copy of your master key (printed
on mount) in a safe place. See below for how gocryptfs is tested.
Only Linux is supported at the moment. [Help wanted for a Mac OS X port.](https://github.com/rfjakob/gocryptfs/issues/15)
Testing
-------
gocryptfs comes with is own test suite that is constantly expanded as features are
added. Run it using `./test.bash`. It takes about 1 minute and requires FUSE
as it mounts several test filesystems.
The `stress_tests` directory contains stress tests that run indefinitely.
In addition, I have ported `xfstests` to FUSE, the result is the
[fuse-xfstests](https://github.com/rfjakob/fuse-xfstests) project. gocryptfs
passes the "generic" tests with one exception, results: [XFSTESTS.md](Documentation/XFSTESTS.md)
A lot of work has gone into this. The testing has found bugs in gocryptfs
as well as in the go-fuse library.
Compile
-------
$ go get github.com/rfjakob/gocryptfs
Use
---
$ mkdir cipher plain
$ $GOPATH/bin/gocryptfs -init cipher
$ $GOPATH/bin/gocryptfs cipher plain
See the [Quickstart](https://nuetzlich.net/gocryptfs/quickstart/) page for more info.
The [MANPAGE.md](Documentation/MANPAGE.md) containes a description of available command-line options.
If you already have gocryptfs installed, run `./MANPAGE-render.bash` to bring up the rendered manpage in
your man pager (requires pandoc).
Storage Overhead
----------------
* Empty files take 0 bytes on disk
* 18 byte file header for non-empty files (2 bytes version, 16 bytes random file id)
* 28 bytes of storage overhead per 4kB block (12 byte nonce, 16 bytes auth tag)
[file-format.md](Documentation/file-format.md) contains a more detailed description.
Performance
-----------
Since version 0.7.2, gocryptfs is as fast as EncFS in the default mode,
and significantly faster than EncFS' "paranoia" mode that provides
a security level comparable to gocryptfs.
gocryptfs uses OpenSSL through a thin wrapper called `stupidgcm`.
This provides a 4x speedup compared to Go's builtin AES-GCM
implementation - see [openssl-gcm.md](Documentation/openssl-gcm.md)
for details. The use of openssl can disabled on the command-line.
Run `./benchmark.bash` to run gocryptfs' canonical set of
benchmarks that include streaming write, extracting a linux kernel
tarball, recursively listing and finally deleting it. The output will
look like this:
```
$ ./benchmark.bash
linux-3.0.tar.gz 100%[==========================>] 92,20M 2,96MB/s in 35s
2016-05-04 19:29:20 URL:https://www.kernel.org/pub/linux/kernel/v3.0/linux-3.0.tar.gz
WRITE: 131072000 bytes (131 MB) copied, 1,43137 s, 91,6 MB/s
UNTAR: 23.25
LS: 1.75
RM: 4.42
```
Changelog
---------
v0.10 (not yet released)
* **Drop dependency to `spacemonkeygo/openssl`**
* gocryptfs now has its own thin wrapper to OpenSSL's GCM implementation
called `stupidgcm`.
* This should fix the [compile issues](https://github.com/rfjakob/gocryptfs/issues/21)
people are seeing with `spacemonkeygo/openssl` and it also gets us
a 20% performance boost for streaming writes.
* Warn but continue anyway if fallocate(2) is not supported by the
underlying filesystem, see [issue #22](https://github.com/rfjakob/gocryptfs/issues/22)
* Enables to use gocryptfs on ZFS, albeit with reduced out-of-space safety.
* **Automatically choose between OpenSSL and Go crypto** [issue #23](https://github.com/rfjakob/gocryptfs/issues/23)
* `-openssl=auto` is the new default
* Go 1.6 added an optimized GCM implementation in amd64 assembly that uses AES-NI.
This is faster than OpenSSL and is used if available.
* In all other cases OpenSSL is much faster and is used instead.
* Passing `-openssl=true/false` overrides the autodetection.
* [Fix statfs](https://github.com/rfjakob/gocryptfs/pull/27), by @lxp
* Fix a fsstress [failure](https://github.com/hanwen/go-fuse/issues/106)
in the go-fuse library.
v0.9, 2016-04-10
* **Long file name support**
* gocryptfs now supports file names up to 255 characters.
* This is a forwards-compatible change. gocryptfs v0.9 can mount filesystems
created by earlier versions but not the other way round.
* Refactor gocryptfs into multiple "internal" packages
* New command-line options:
* `-longnames`: Enable long file name support (default true)
* `-nosyslog`: Print messages to stdout and stderr instead of syslog (default false)
* `-wpanic`: Make warning messages fatal (used for testing)
* `-d`: Alias for `-debug`
* `-q`: Alias for `-quiet`
v0.8, 2016-01-23
* Redirect output to syslog when running in the background
* New command-line option:
* `-memprofile`: Write a memory allocation debugging profile the specified
file
v0.7.2, 2016-01-19
* **Fix performance issue in small file creation**
* This brings performance on-par with EncFS paranoia mode, with streaming writes
significantly faster
* The actual [fix](https://github.com/hanwen/go-fuse/commit/c4b6b7949716d13eec856baffc7b7941ae21778c)
is in the go-fuse library. There are no code changes in gocryptfs.
v0.7.1, 2016-01-09
* Make the `build.bash` script compatible with Go 1.3
* Disable fallocate on OSX (system call not availabe)
* Introduce pre-built binaries for Fedora 23 and Debian 8
v0.7, 2015-12-20
* **Extend GCM IV size to 128 bit from Go's default of 96 bit**
* This pushes back the birthday bound to make IV collisions virtually
impossible
* This is a forwards-compatible change. gocryptfs v0.7 can mount filesystems
created by earlier versions but not the other way round.
* New command-line option:
* `-gcmiv128`: Use 128-bit GCM IVs (default true)
v0.6, 2015-12-08
* **Wide-block filename encryption using EME + DirIV**
* EME (ECB-Mix-ECB) provides even better security than CBC as it fixes
the prefix leak. The used Go EME implementation is
https://github.com/rfjakob/eme which is, as far as I know, the first
implementation of EME in Go.
* This is a forwards-compatible change. gocryptfs v0.6 can mount filesystems
created by earlier versions but not the other way round.
* New command-line option:
* `-emenames`: Enable EME filename encryption (default true)
v0.5.1, 2015-12-06
* Fix a rename regression caused by DirIV and add test case
* Use fallocate to guard against out-of-space errors
v0.5, 2015-12-04
* **Stronger filename encryption: DirIV**
* Each directory gets a random 128 bit file name IV on creation,
stored in `gocryptfs.diriv`
* This makes it impossible to identify identically-named files across
directories
* A single-entry IV cache brings the performance cost of DirIV close to
zero for common operations (see performance.txt)
* This is a forwards-compatible change. gocryptfs v0.5 can mount filesystems
created by earlier versions but not the other way round.
* New command-line option:
* `-diriv`: Use the new per-directory IV file name encryption (default true)
* `-scryptn`: allows to set the scrypt cost parameter N. This option
can be used for faster mounting at the cost of lower brute-force
resistance. It was mainly added to speed up the automated tests.
v0.4, 2015-11-15
* New command-line options:
* `-plaintextnames`: disables filename encryption, added on user request
* `-extpass`: calls an external program for prompting for the password
* `-config`: allows to specify a custom gocryptfs.conf path
* Add `FeatureFlags` gocryptfs.conf paramter
* This is a config format change, hence the on-disk format is incremented
* Used for ext4-style filesystem feature flags. This should help avoid future
format changes. The first user is `-plaintextnames`.
* On-disk format 2
v0.3, 2015-11-01
* **Add a random 128 bit file header to authenticate file->block ownership**
* This is an on-disk-format change
* On-disk format 1
v0.2, 2015-10-11
* Replace bash daemonization wrapper with native Go implementation
* Better user feedback on mount failures
v0.1, 2015-10-07
* First release
* On-disk format 0
See https://github.com/rfjakob/gocryptfs/tags for the release dates and associated
git tags.
|
