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Update README + docs for v0.6 release

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Jakob Unterwurzacher 2015-12-08 16:41:45 +01:00
parent e3f35d38b5
commit 9419e7ae85
4 changed files with 32 additions and 17 deletions
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11
Documentation/SECURITY.md
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@ -15,7 +15,7 @@ The KEK is generated from the user password using `scrypt`.
File Contents
-------------
All file contents are encrypted using AES-256-GCM.
All file contents are encrypted using AES-256-GCM (Galois/Counter Mode).
Files are segmented into 4KB blocks. Each block gets a fresh random
96 bit IV each time it is modified. A 128-bit authentication tag (GHASH)
@ -37,8 +37,11 @@ File Names
Every directory gets a 128-bit directory IV that is stored in each
directory as `gocryptfs.diriv`.
File names are encrypted using AES-256-CBC with the directory IV as
initialization vector. The Base64 encoding limits the usable filename length
to 176 characters.
File names are encrypted using AES-256-EME (ECB-Mix-ECB wide-block encryption,
see https://github.com/rfjakob/eme for details) with the directory IV
as initialization vector. EME fixes the prefix leak that occours with CBC
encryption.
![](https://rawgit.com/rfjakob/gocryptfs/master/Documentation/file-name-encryption.svg)
The Base64 encoding limits the usable filename length to 176 characters.

14
Documentation/file-name-encryption.svg
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@ -149,9 +149,9 @@
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@ -186,7 +186,7 @@
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@ -359,14 +359,14 @@
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7
Documentation/performance.txt
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@ -2,11 +2,12 @@ All test performed on tmpfs, /tmp/a mounted on /tmp/b.
The used test archive is https://www.kernel.org/pub/linux/kernel/v3.0/linux-3.0.tar.gz .
UNTAR: tar xfz ../linux-3.0.tar.gz
LS: ls -lR > /dev/null
RM: rm -rf linux-3.0
LS: ls -lR linux-3.0 > /dev/null
RM: rm -Rf linux-3.0
VERSION UNTAR LS RM
v0.4 48 1.5 5
v0.5-rc1 56 7 19
v0.5-rc1-1 54 4.1 9
v0.5-rc1-2 45 1.7 3.4
v0.5-rc1-2 45 1.7 3.4
v0.6 47 1.8 4.3

17
README.md
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@ -6,10 +6,10 @@ 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](https://github.com/vgough/encfs)
and strives to fix its security issues (see EncFS tickets 9, 13, 14, 16).
This project was inspired by EncFS and strives to fix its security
issues while providing good performance.
For details on the security of gocryptfs see the
[SECURITY.md](Documentation/SECURITY.md) document.
[SECURITY.md](Documentation/SECURITY.md) design document.
Current Status
--------------
@ -97,6 +97,17 @@ The output should look like this:
Changelog
---------
v0.6
* **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 v0.5 can mount filesystems
created by earlier version but not the other way round.
* New command-line option:
* `-emenames`: Enable EME filename encryption (default true)
v0.5
* **Stronger filename encryption: DirIV**
* Each directory gets a random 128 bit file name IV on creation,