Commit Graph

112 Commits

Author SHA1 Message Date
Jakob Unterwurzacher
b883dd10a6 reverse: add symlink encryption and Readlink support 2016-09-25 18:01:24 +02:00
Jakob Unterwurzacher
12808138ef contentenc: add "ExternalNonce" mode
This will be used for strong symlink encryption in reverse mode.
2016-09-25 17:44:19 +02:00
Jakob Unterwurzacher
32e55261ca fusefrontend: handle Readlink directly
Calling into go-fuse's loopbackFileSystem does not add
any value here.
2016-09-25 17:01:39 +02:00
Jakob Unterwurzacher
2050c7f3b3 reverse: add gcmsiv flag and associated tests 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
7bbf6ad6ea reverse: derive file ID and block IVs from file paths 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
52a6f4f71e reverse: add longnameParentCache
findLongnameParent has to read the whole directory to find the
right file; add a simple cache to avoid most directory scans.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
a6a7b424f8 reverse: resolve long names in Open and GetAttr
The last patch added functionality for generating gocryptfs.longname.*
files, this patch adds support for mapping them back to the full
filenames.

Note that resolving a long name needs a full readdir. A cache
will be implemented later on to improve performance.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
35bcc2dca2 reverse: transform long names in OpenDir 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
b34a665da4 nametransform: implement ReadDirIV without Openat
As ReadDirIV operates on a path anyway, opening the directory
has no clear safety advantage w.r.t. concurrent renames.

If the backing directory is a reverse-mounted gocryptfs filesystem,
each directory open is an OPENDIR, and this causes a full directory
read!

This patch improves the "ls -lR" performance of an

  DIR --> gocryptfs-reverse --> gocryptfs

chain by a factor of ~10.

OPENDIR counts for ls -lR:
  Before 15570
  After   2745
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
01c18dbcab nametransform: return EINVAL on invalid padding
With the generic fmt.Errorf we trigger a warning from go-fuse:

  2016/09/21 21:42:31 can't convert error type: Invalid padding
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
d76e7aadb4 reverse: use dynamic inode numbers
...with stable mappings for hard-linked files.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
5f726aaa9d contentenc: add GCM-SIV support
Also add ReverseDummyNonce nonce generation.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
7f87ed78f2 cryptocore: add support for GCM-SIV 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
d1762c5b95 reverse: fix GetAttr for gocryptfs.conf
And also don't return the encrypted version of
.gocryptfs.reverse.conf in readdir.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
3d59c7dd6a reverse: add gocryptfs.conf passthrough 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
1932248446 reverse: get rid of debug message 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
ce22ab36e1 reverse: gocryptfs.diriv content was generated from wrong path
Should be derived from the directory name only.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
7faa267bd4 reverse: rename readFile to clearer readBackingFile
Also refactor the header generation for nicer code.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
be9dfe3a89 reverse: implement dynamic diriv
Introduce a unique per-directory diriv that is generated
by hashing the encrypted directory path.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
10f38e8870 reverse: generate file header for Read()
Also create virtual gocryptfs.diriv entries (no content yet).
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
ac1221395e nametransform: export DirIVLen constant
Will be needed by reverse mode.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
e42ab3908d reverse: print value in file offset panic 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
777eb8e62f reverse: rename types to reverseXYZ
...to prevent confusion with the forward variants.

FS   -> reverseFS
file -> reverseFile

Also add an incomplete read implementation.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
5931eea387 contentenc: add helpers for reverse mode
Add the reverse variant of DecryptBlocks etc:

* EncryptBlocks
* JointPlaintextRange
* ExplodeCipherRange
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
1d4c6288f2 main: initial support for reverse mode 2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
1d62086742 conentenc: handle zero-sized files in PlainSizeToCipherSize
Previously caused an integer underflow.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
9237b4f53e reverse: add skeleton
Compiles but does not do much else.
2016-09-25 16:43:17 +02:00
Jakob Unterwurzacher
fca1b82417 fusefrontend: relay Utimens to go-fuse
Commit af5441dcd9 has caused a
regression ( https://github.com/rfjakob/gocryptfs/issues/35 )
that is fixed by this commit.

The go-fuse library by now has all the syscall wrappers in
place to correctly handle Utimens, also for symlinks.

Instead of duplicating the effort here just call into go-fuse.

Closes #35
2016-09-25 16:30:29 +02:00
Jakob Unterwurzacher
af5441dcd9 fusefrontend: use NsecToTimespec() for Utimens
This fixes a build problem on 32-bit hosts:

  internal/fusefrontend/file.go:400: cannot use a.Unix() (type int64) as
  type int32 in assignment
  internal/fusefrontend/file.go:406: cannot use m.Unix() (type int64) as
  type int32 in assignment

It also enables full nanosecond timestamps for dates
after 1970.
2016-08-09 22:18:46 +02:00
Jakob Unterwurzacher
7395b8e990 cryptocore: comment why 96-bit IVs are still supported 2016-07-31 13:36:38 +02:00
Jakob Unterwurzacher
e8a234f658 Add godoc comments to all internal packages 2016-07-06 21:51:25 +02:00
Jakob Unterwurzacher
603e144f5e prefer_openssl: OSX: get rid of /proc warnings
OSX does not have /proc/cpuinfo, but let's not warn
the user about it.
2016-07-04 08:19:26 +02:00
Jakob Unterwurzacher
52655843ab stupidgcm: use __builtin_trap()
[...]/stupidgcm/locking.go:16:2:
  warning: indirection of non-volatile null pointer will
  be deleted, not trap [-Wnull-dereference]
  [...]/stupidgcm/locking.go:16:2:
  note: consider using __builtin_trap() or qualifying
  pointer with 'volatile'

https://github.com/rfjakob/gocryptfs/issues/15
2016-07-04 08:14:24 +02:00
Jakob Unterwurzacher
741bf0726e syscallcompat: OSX: add Mknodat wrapper
Protip: find naked *at syscalls using:

   git grep "syscall." | grep "at(" | grep -v syscallcompat
2016-07-03 20:22:22 +02:00
Jakob Unterwurzacher
d8524c7369 syscallcompat: OSX: add Unlinkat wrapper
Also, replace remaining naked syscall.Openat calls.
2016-07-03 20:17:40 +02:00
Jakob Unterwurzacher
1d7728959c fusefrontend: downgrade Renameat log message to debug 2016-07-03 20:08:09 +02:00
Jakob Unterwurzacher
79851bf6cc syscallcompat: OSX: add Renamat wrapper
Adds a poor man's renameat implementation for OSX.
2016-07-03 20:05:32 +02:00
Jakob Unterwurzacher
9b725c15cf syscallcompat: OSX: add Fallocate and Openat wrappers
...and convert all calls to syscall.{Fallocate,Openat}
to syscallcompat .

Both syscalls are not available on OSX. We emulate Openat and just
return EOPNOTSUPP for Fallocate.
2016-07-03 19:18:34 +02:00
Jakob Unterwurzacher
c9a472c12f syscallcompat: move syscall wrapper to their own package
We will get more of them as OSX also lacks support for openat.
2016-07-03 17:51:40 +02:00
Jakob Unterwurzacher
e574a6cc1f nametransform: hide detailed padding error behind the debug flag
unPad16 returns detailed errors including the position of the
incorrect bytes. Kill a possible padding oracle by lumping
everything into a generic error.

The detailed error is only logged if debug is active.
2016-07-03 15:35:58 +02:00
Jakob Unterwurzacher
54470baa23 fusefrontend: add fallocate support
Mode=0 (default) and mode=1 (keep size) are supported.
The patch includes test cases and the whole thing passed xfstests.

Fixes https://github.com/rfjakob/gocryptfs/issues/1 .
2016-07-02 19:52:09 +02:00
Jakob Unterwurzacher
04ad063515 fusefronted: move Truncate() and Allocate() to their own file
These are large complicated implementations that will share some
code.
2016-07-02 15:35:06 +02:00
Jakob Unterwurzacher
7b22b426b9 contentenc: rename PlaintextRange and CiphertextRange
The name could be misunderstood and actually caused a bug:
doWrite used to always preallocate 4128 instead of the actual
data length.
2016-07-02 00:12:36 +02:00
Jakob Unterwurzacher
f2b4d57068 fusefrontend: coalesce grows in Truncate()
We were growing the file block-by-block which was pretty
inefficient. We now coalesce all the grows into a single
Ftruncate. Also simplifies the code!

Simplistic benchmark: Before:

  $ time truncate -s 1000M foo
  real	0m0.568s

After:

  $ time truncate -s 1000M foo
  real	0m0.205s
2016-07-01 23:32:27 +02:00
Jakob Unterwurzacher
ae77d18527 fusefrontend: better comments for Truncate 2016-07-01 09:23:04 +02:00
Jakob Unterwurzacher
e994ffa27d fusefrontend: handle dir-overwrites-dir on XFS
XFS returns a different error code if you try to overwrite
a non-empty directory with a directory:

XFS:  mv: cannot move ‘foo’ to ‘bar/foo’: File exists
ext4: mv: cannot move 'foo' to 'bar/foo': Directory not empty

So have EEXIST trigger the Rmdir logic as well.

Fixes issue #20
Link: https://github.com/rfjakob/gocryptfs/issues/20
2016-06-30 23:17:54 +02:00
Jakob Unterwurzacher
c400aca5cf tlog: clean up messages from the go-fuse library
Drop the date and add the "go-fuse: " prefix so you can see
where the message is coming from.

Before:
  Jun 27 09:03:15 brikett gocryptfs[4150]: 2016/06/27 09:03:15 Unimplemented opcode INTERRUPT
After:
  Jun 27 09:10:58 brikett gocryptfs[4961]: go-fuse: Unimplemented opcode INTERRUPT
2016-06-27 09:12:03 +02:00
Jakob Unterwurzacher
3288d98703 fusefrontend: fix PlaintextNames versions of Mkdir, Rmdir
The "!fs.args.DirIV" special case was removed by b17f0465c7
but that, by accident, also removed the handling for
PlaintextNames.

Re-add it as an explicit PlaintextNames special case.

Also adds support for removing directories that miss their
gocryptfs.diriv file for some reason.
2016-06-27 00:27:36 +02:00
Jakob Unterwurzacher
547ddf4264 tlog: switch default logger to syslog
...unless "-nosyslog" is passed.

All gocryptfs messages already go to syslog, but the messages
that the go-fuse lib emits were still printed to stdout.

Fixes issue #13 ( https://github.com/rfjakob/gocryptfs/issues/13 )
2016-06-26 23:30:22 +02:00
Jakob Unterwurzacher
0115588680 main, fusefrontend: enable suid functionality
FUSE filesystems are mounted with "nosuid" by default. If we run as root,
we can use device files by passing the opposite mount option, "suid".

Also we have to use syscall.Chmod instead of os.Chmod because the
portability translation layer "syscallMode" messes up the sgid
and suid bits.

Fixes 70% of the failures in xfstests generic/193. The remaining are
related to truncate, but we err on the safe side:

    $ diff -u tests/generic/193.out /home/jakob/src/fuse-xfstests/results//generic/193.out.bad
    [...]
     check that suid/sgid bits are cleared after successful truncate...
     with no exec perm
     before: -rwSr-Sr--
    -after:  -rw-r-Sr--
    +after:  -rw-r--r--
2016-06-26 20:13:21 +02:00