76311b60f2
Format: [ "Version" uint16 big endian ] [ "Id" 16 random bytes ] Quoting SECURITY.md: * Every file has a header that contains a 16-byte random *file id* * Each block uses the file id and its block number as GCM *authentication data* * This means the position of the blocks is protected as well. The blocks can not be reordered or copied between different files without causing an decryption error.
GoCryptFS 
An encrypted overlay filesystem focused on security and correctness.
gocryptfs is built on top the excellent go-fuse FUSE library and its LoopbackFileSystem API.
This project was inspired by EncFS and strives to fix its security issues (see EncFS tickets 9, 13, 14, 16). For details on the security of GoCryptFS see the SECURITY.md document.
Current Status
- First public release
- Feature-complete
- Passes the fuse-xfstests "generic" tests with one exception, results: XFSTESTS.md
- A lot of work has gone into this. The testing has found bugs in gocryptfs as well as in go-fuse.
- The one exceptions generic/035. This is a limitation in go-fuse, check out https://github.com/hanwen/go-fuse/issues/55 for details.
- However, gocryptfs needs more real-world testing - please report any issues via github.
- Only Linux operation has been tested. Help wanted for a Mac OS X port.
Install
$ go get github.com/rfjakob/gocryptfs
Use
$ mkdir cipher plain
$ $GOPATH/bin/gocryptfs --init cipher
[...]
$ $GOPATH/bin/gocryptfs cipher plain
[...]
$ echo test > plain/test.txt
$ ls -l cipher
total 8
-rw-rw-r--. 1 user user 33 7. Okt 23:23 0ao8Hyyf1A-A88sfNvkUxA==
-rw-rw-r--. 1 user user 233 7. Okt 23:23 gocryptfs.conf
$ fusermount -u plain
Performance
- 28 bytes of storage overhead per block (16 bytes auth tag, 12 byte nonce)
- uses openssl through spacemonkeygo/openssl
for a 3x speedup compared to
crypto/cipher(see go-vs-openssl.md for details
Run ./benchmark.bash to run the test suite and the streaming read/write
benchmark. The benchmark is run twice, first with native Go crypto and
second using openssl.
The output should look like this:
$ ./benchmark.bash
[...]
BenchmarkStreamWrite 100 11816665 ns/op 88.74 MB/s
BenchmarkStreamRead 200 7848155 ns/op 133.61 MB/s
ok github.com/rfjakob/gocryptfs 9.407s
Changelog
v0.3 (in progress)
- Add file header that contains a random id to authenticate blocks
- This is an on-disk-format change
v0.2
- Replace bash daemonization wrapper with native Go implementation
- Better user feedback on mount failures
v0.1
- First release
See https://github.com/rfjakob/gocryptfs/releases for the release dates and associated tags.