Commit Graph

284 Commits

Author SHA1 Message Date
Sebastian Lackner
a1ba4b6576 Omit syscall.O_RDONLY flag when passing O_PATH.
When O_PATH is specified in flags, flag bits other than O_CLOEXEC, O_DIRECTORY,
and O_NOFOLLOW are ignored.
2019-01-03 18:24:05 +01:00
Jakob Unterwurzacher
71d07b7c73 tests: extractloop: renice to level 19
Run at low priority to not annoy the user too much.
2019-01-03 16:14:05 +01:00
Jakob Unterwurzacher
bb9884549b tests: allow one extra fd in fd leak detector (dirCache)
The gocryptfs process may keep one fd open for up to one second
in the dirCache.
2019-01-03 15:38:51 +01:00
Jakob Unterwurzacher
f6dad8d0fa nametransform: simplify WriteDirIV to WriteDirIVAt
Un-spaghettify the function and let the callers open
the directory.
2019-01-03 15:31:13 +01:00
Jakob Unterwurzacher
59f1300591 tests: retry longer when we see a fd leak
Hopefully gets rid of the false positives on travis.
2019-01-02 21:03:26 +01:00
Jakob Unterwurzacher
d269c28d16 tests: xattr: set on 0200 file, list on 0000 file
https://github.com/rfjakob/gocryptfs/issues/308
2019-01-02 20:45:55 +01:00
Jakob Unterwurzacher
55a27a47df tests: better error message for TestBase64XattrRead
Make clear what we have and what we want.
2019-01-02 16:55:51 +01:00
Jakob Unterwurzacher
772afa93f9 tests: add fd leak retry logic to UnmountErr, really return error
Give the gocryptfs process one extra millisecond to close
files. Allows us to drop several other sleeps.

UnmountErr now really returns an error when it detects an fd leak
instead of just printing a message.
2019-01-02 01:09:09 +01:00
Jakob Unterwurzacher
d5a74d2a3e tests: ListFds(): filter out pipe and eventpoll fds
These are created on demand by the Go runtime and are usually
not interesting.
2019-01-02 00:09:17 +01:00
Jakob Unterwurzacher
b1819143c5 tests: make MountInfo field accessible
Tests outside the test_helpers package may want to look
at this.
2019-01-02 00:09:17 +01:00
Jakob Unterwurzacher
035b3367b7 tests: reverse: add ctlsocket cleanup delay 2019-01-02 00:09:17 +01:00
Jakob Unterwurzacher
035834dd51 tests: ListFds: show r/w status
Also, drop entries that disappear while we stat them.
2019-01-01 22:27:40 +01:00
Jakob Unterwurzacher
e276e255dc tests: split mount_unmount.go from helpers.go
With the FD leak logic, the mount/unmount functions have
become complex enough to give them their own file.
2019-01-01 22:27:10 +01:00
Jakob Unterwurzacher
10de105c13 tests: detect fd leaks on unmount
For now, this only prints a message but does not fail the tests.
2019-01-01 22:01:49 +01:00
Jakob Unterwurzacher
887d5aa8e7 tests: teach ListFds() to check other processes 2019-01-01 20:05:38 +01:00
Jakob Unterwurzacher
817c485bb7 tests: save gocryptfs process id in test_helpers.MountPID
This will allow to tests to monitor fd usage and maybe other things.
2019-01-01 19:34:12 +01:00
Jakob Unterwurzacher
60e7a0ca9f fusefrontend: xattr: fix hang on FIFOs
An Open() a fifo blocks until it is opened for writing.
This meant that xattr operations on FIFOs would block.
Pass O_NONBLOCK to fix that, and add a test.
2019-01-01 16:24:25 +01:00
Jakob Unterwurzacher
2286372603 fusefrontend: make GetXAttr() symlink-safe on Linux
Uses the /proc/self/fd trick, which does not work
on Darwin.
2019-01-01 16:24:25 +01:00
Jakob Unterwurzacher
b97d7d1d33 tests: add Flistxattr/Fgetxattr/Fremovexattr tests
Test for the upcoming fd-based xattr support.
2019-01-01 16:24:25 +01:00
Jakob Unterwurzacher
ed6ed513d7 fusefrontend: make Access() symlink-safe.
Make Access() symlink-safe through use of faccessat.
2019-01-01 16:24:09 +01:00
Sebastian Lackner
874eaf9734 Assorted spelling fixes.
Mostly detected with the 'codespell' utility, but also includes some
manual grammar fixes.
2018-12-27 15:19:55 +01:00
Jakob Unterwurzacher
e537ecbe2e tests: fix golint error
Error was:

  tests/cli/cli_test.go:552: declaration of "err" shadows declaration at tests/cli/cli_test.go:544
2018-10-11 20:57:52 +02:00
Jakob Unterwurzacher
04241455a2 tests: add idle timeout test
Mount with idle timeout 10ms and check that the process exits by itself
within 5 seconds.
2018-10-11 20:43:28 +02:00
Jakob Unterwurzacher
4f2feb1be7 tests: catch "name too long" symlink failure on XFS
Retry with length 1000 if length 4000 fails, which
should work on all filesystems.

Failure was:

  --- FAIL: TestTooLongSymlink (0.00s)
      correctness_test.go:198: symlink xxx[...]xxxx /tmp/xfs.mnt/gocryptfs-test-parent/549823072/365091391/TooLongSymlink: file name too long

https://github.com/rfjakob/gocryptfs/issues/267
2018-10-10 22:40:55 +02:00
Jakob Unterwurzacher
5a1ebdb4f7 tests: respect TMPDIR if set
Setting TMPDIR now allows to run the tests against
a directory of your choice, making it easier to test
different filesystems.
2018-10-10 22:24:20 +02:00
Jakob Unterwurzacher
c270b21efc fusefrontend: get rid of os.File* wrapping
Directly use int file descriptors for the dirfd
and get rid of one level of indirection.
2018-09-23 12:17:26 +02:00
Jakob Unterwurzacher
05c8d4a1c4 tests: add symlink_race tool
Help uncover symlink races.
2018-09-23 12:17:26 +02:00
Jakob Unterwurzacher
9e6ee47bc9 tests: detect and report chmod failures earlier
Instead of reporting the consequence:

    matrix_test.go:906: modeHave 0664 != modeWant 0777

Report it if chmod itself fails, and also report the old file mode:

    matrix_test.go:901: chmod 000 -> 777 failed: bad file descriptor
2018-09-22 13:39:17 +02:00
Jakob Unterwurzacher
5ca6243eeb main: sanitize commas from fsname
The cipherdir path is used as the fsname, as displayed
in "df -T". Now, having a comma in fsname triggers a sanity check
in go-fuse, aborting the mount with:

  /bin/fusermount: mount failed: Invalid argument
  fuse.NewServer failed: fusermount exited with code 256

Sanitize fsname by replacing any commas with underscores.

https://github.com/rfjakob/gocryptfs/issues/262
2018-09-18 19:39:52 +02:00
Jakob Unterwurzacher
e8d8ae54d3 fusefrontend: use OpenDirNofollow in openBackingDir
Rename openBackingPath to openBackingDir and use OpenDirNofollow
to be safe against symlink races. Note that openBackingDir is
not used in several important code paths like Create().

But it is used in Unlink, and the performance impact in the RM benchmark
to be acceptable:

Before

	$ ./benchmark.bash
	Testing gocryptfs at /tmp/benchmark.bash.bYO: gocryptfs v1.6-12-g930c37e-dirty; go-fuse v20170619-49-gb11e293; 2018-09-08 go1.10.3
	WRITE: 262144000 bytes (262 MB, 250 MiB) copied, 1.07979 s, 243 MB/s
	READ:  262144000 bytes (262 MB, 250 MiB) copied, 0.882413 s, 297 MB/s
	UNTAR: 16.703
	MD5:   7.606
	LS:    1.349
	RM:    3.237

After

	$ ./benchmark.bash
	Testing gocryptfs at /tmp/benchmark.bash.jK3: gocryptfs v1.6-13-g84d6faf-dirty; go-fuse v20170619-49-gb11e293; 2018-09-08 go1.10.3
	WRITE: 262144000 bytes (262 MB, 250 MiB) copied, 1.06261 s, 247 MB/s
	READ:  262144000 bytes (262 MB, 250 MiB) copied, 0.947228 s, 277 MB/s
	UNTAR: 17.197
	MD5:   7.540
	LS:    1.364
	RM:    3.410
2018-09-08 19:27:33 +02:00
Jakob Unterwurzacher
84d6fafeca tests: restore Go 1.7 compatibility
Go 1.7 does not have t.Name() yet.
2018-09-08 18:19:53 +02:00
Jakob Unterwurzacher
930c37e03d syscallcompat: use O_PATH in OpenDirNofollow
This fixes the "0100 directory" problem in reverse mode,
and should be slightly faster.
2018-09-08 18:06:33 +02:00
Jakob Unterwurzacher
bc14f8dcb6 tests: add chmod test
Makes sure we don't add regressions when fixing
https://github.com/rfjakob/gocryptfs/issues/259
2018-09-08 17:00:23 +02:00
Jakob Unterwurzacher
21b5fae0e6 tests: restore TestUtimesNanoSymlink
The function seems to have been renamed by 426b9536 by mistake.
Rename it back so the test is run again.
2018-09-08 16:36:01 +02:00
Jakob Unterwurzacher
ca24c20694 main: don't read the config file twice (fix pipe bug)
Instead, first Load() the file, then DecryptMasterKey().

Fixes https://github.com/rfjakob/gocryptfs/issues/258
2018-09-08 13:04:33 +02:00
Jakob Unterwurzacher
2bdf7d5172 configfile: add LoadAndDecrypt wrapper
Callers that do not want to decrypt the masterkey should
call plain Load().

https://github.com/rfjakob/gocryptfs/issues/258
2018-09-08 12:40:29 +02:00
Jakob Unterwurzacher
5acfbc1b2f main: add -e as an alias for -exclude 2018-08-15 13:12:13 +02:00
Jakob Unterwurzacher
ec2fdc19cf reverse mode: add --exclude option
https://github.com/rfjakob/gocryptfs/issues/235
2018-08-11 23:26:49 +02:00
Jakob Unterwurzacher
06f1ea951b tests: VerifyExistence: panic on inconsistent results
In the past we did not check whether all methods of checking
the file return the same result. We should.
2018-08-11 22:37:22 +02:00
Jakob Unterwurzacher
2d68b06f9d fsck: handle sparse files efficiently, fix xfstests generic/285
If we encounter a 128KB block of zeros, try to skip to the next
data section by calling File.SeekData().

This fixes xfstests generic/285, which creates a 17TB sparse file,
and runs fsck afterwards. Without this optimization, fsck would
take ages.
2018-07-01 21:48:51 +02:00
Jakob Unterwurzacher
9a15dfa494 trezor: add TrezorPayload
TrezorPayload stores 32 random bytes used for unlocking
the master key using a Trezor security module. The randomness makes sure
that a unique unlock value is used for each gocryptfs filesystem.
2018-07-01 20:56:22 +02:00
Jakob Unterwurzacher
91de77943f configfile: reduce function name stutter
configfile.LoadConfFile()   -> configfile.Load()
configfile.CreateConfFile() -> configfile.Create()
2018-07-01 20:56:22 +02:00
Jakob Unterwurzacher
8e5ca7299a trezor: exit with usage error if used together with -extpass
Using an external program for the Trezor PIN is not supported
at the moment.
2018-07-01 20:56:22 +02:00
Jakob Unterwurzacher
4bf02f4760 trezor: add basic "-init -trezor" test
Verify that the Trezor feature flag is set after "-init -trezor".
2018-07-01 20:56:09 +02:00
Jakob Unterwurzacher
c6f6e8ec4d trezor: add skeleton for Trezor support
readpassword.Trezor() is not implemented yet and returns
a hardcoded dummy key.
2018-07-01 20:56:04 +02:00
Jakob Unterwurzacher
53d6a9999d main: accept -dev, -nodev, -suid, -nosuid, -exec, -noexec
When mounted via /etc/fstab like this,

  /a /b fuse.gocryptfs default 0 0

we always get extra options passed. As reported by @mahkoh
at https://github.com/rfjakob/gocryptfs/pull/233 :

  mount passes `-o noexec` if `-o user` is set and `-o exec` is not set.
  If both `-o user` and `-o exec` are set, it passes `-o exec`.

Make these options work, and in addtion, also make -suid and -rw
work the same way.

Reported-by: @mahkoh
2018-06-07 22:50:30 +02:00
Jakob Unterwurzacher
e29a81efc3 main: make prefixOArgs errors testable
By returning an error instead of calling os.Exit,
error cases can be tested easily. Error cases
were not tested until now.
2018-06-05 21:02:35 +02:00
Jakob Unterwurzacher
ae02ca1ded xattr: use LGet/LSet etc
Support has been merged into the xattr package
( https://github.com/pkg/xattr/pull/29 ), use it.
2018-05-27 20:09:48 +02:00
Jakob Unterwurzacher
44caf21deb tests: add "mv broken symlink" test
This currently fails because we do not use llistxattr
yet.
2018-05-17 23:14:33 +02:00
Jakob Unterwurzacher
7b00681807 xattr: return EOPNOTSUPP for unsupported attributes
mv is unhappy when we return EPERM when it tries to set
system.posix_acl_access:

   mv: preserving permissions for ‘b/x’: Operation not permitted

Now we return EOPNOTSUPP like tmpfs does and mv seems happy.
2018-05-15 23:00:47 +02:00
Jakob Unterwurzacher
f7a6f4d468 fsck: update testcases with binary xattrs 2018-05-10 23:26:00 +02:00
Bolshevik
a41ec2028c xattr: optimize storage, store as binary instead of bae64
Values a binary-safe, there is no need to base64-encode them.

Old, base64-encoded values are supported transparently
on reading. Writing xattr values now always writes them binary.
2018-05-10 23:25:49 +02:00
Jakob Unterwurzacher
fc8fca04a8 tests: example_filesystems: create a private copy in /tmp
The tests write to the example_filesystems folder, which
1) May leave your source tree in a modified state
2) Triggers test failures when the fsck tests run concurrently,
   which happens on Travis CI every now and then.

Fix both problem by copying the example_filesystems folder
to a private location in /tmp.
2018-05-04 22:27:59 +02:00
Jakob Unterwurzacher
996d2f141b tests: helpers: fix a few error reports
These were using stale err values.
2018-04-27 20:19:51 +02:00
Jakob Unterwurzacher
bcc8378a2c Fix the easy golint warnings
Reported by https://goreportcard.com/report/github.com/rfjakob/gocryptfs
2018-04-08 20:26:25 +02:00
Jakob Unterwurzacher
cab0cda449 tests: retry umount
Gnome may still have files open causing spurious test
failures.
2018-04-08 20:09:05 +02:00
Jakob Unterwurzacher
9d7392a5be tests: cli_test: fix fd leak
One fd leak found in TestMountBackground.
2018-04-07 15:46:41 +02:00
Jakob Unterwurzacher
22031d7e53 tests: matrix: check for fd leaks
And fix two in test_helpers.Mount().

Leftover fds can cause an unmount failure like this later:
fusermount: failed to unmount /tmp/gocryptfs-test-parent/873632270/default-plain: Device or resource busy
so try to catch them early.
2018-04-07 15:24:00 +02:00
Jakob Unterwurzacher
8b443c8484 fsck: add xattr support
With testcases.
2018-04-02 20:25:59 +02:00
Jakob Unterwurzacher
a0fd3eca98 fsck: test against example_filesystems 2018-04-02 18:43:50 +02:00
Jakob Unterwurzacher
b6c8960b01 fsck: clean up log output
Make sure we get only 1 warning output per
problem.

Also, add new corruption types to broken_fs_v1.4.
2018-04-02 18:32:30 +02:00
Jakob Unterwurzacher
f28d85fad5 fsck: add initial implementation
Most corruption cases except xattr should be covered.
With test filesystem.

The output is still pretty ugly. xattr support will
be added in the next commits.
2018-04-02 16:38:18 +02:00
Jakob Unterwurzacher
6e637f38ff tests: add a few explicit file Close() in matrix_test
These can cause EBUSY errors when unmounting.
2018-04-01 14:51:07 +02:00
Jakob Unterwurzacher
8fcd39a3b0 main: add "-fsck" flag
The fsck operation is not yet implemented, this commits
just adds the flag and improves cli flag handling.
2018-04-01 14:25:10 +02:00
Jakob Unterwurzacher
1a3d04ab87 Switch from private copy to pkg/xattr
Now that https://github.com/pkg/xattr/pull/24
has been merged there is no reason to keep
our private copy.

Switch to the upstream version.
2018-03-28 19:19:58 +02:00
Jakob Unterwurzacher
b1f362d28a tests: replace xattr.Supported
This function has been deprecated by the pkg/xattr
upstream, so write our own.
2018-03-26 21:54:17 +02:00
Jakob Unterwurzacher
db778aae7d fusefrontend: handle empty xattrs efficiently
We handle empty files by storing an actual empty file
on disk. Handle xattrs similarily and encrypt the
empty value to the empty value.
2018-03-25 21:06:10 +02:00
Jakob Unterwurzacher
1ed3d51df1 fusefrontend: add xattr support
At the moment, only for reverse mode.

https://github.com/rfjakob/gocryptfs/issues/217
2018-03-25 21:06:10 +02:00
Jakob Unterwurzacher
f20974c4da test_helpers: add SwitchTestParentDir
SwitchTestParentDir changes testParentDir. This is used when you want
to perform tests on a special filesystem. For example, the xattr tests
cannot run on tmpfs and use /var/tmp instead of /tmp.
2018-03-24 21:40:11 +01:00
Jakob Unterwurzacher
9bc039a4ba Add -masterkey=stdin functionality
https://github.com/rfjakob/gocryptfs/issues/218
2018-03-22 00:02:10 +01:00
Jakob Unterwurzacher
4b75b578a2 tests: extractloop.sh: better cleanup logic, handle missing /proc
macos does not have /proc, so don't try to read it.
2018-03-13 22:41:26 +01:00
Jakob Unterwurzacher
e46f6b940f tests: extractloop.sh: don't abort if md5sum is missing
MacOS does not have it installed by default.
2018-03-13 22:16:15 +01:00
Jakob Unterwurzacher
8373410678 macos: extractloop.sh: exclude symlink & mute ln error message
Extracting the symlink fails with

	linux-3.0/arch/microblaze/boot/dts/system.dts: Can't set permissions to 0755

so just exclude it.

The ln error Looks scary but is harmless, so get rid of it.
The symlink is only created to make it more convenient to view the
csv log.
2018-03-07 21:36:52 +01:00
Jakob Unterwurzacher
51de6cd940 macos: tests: make extractloop.bash work on macos
macos' bash and ln lack a few features we used.
2018-03-07 20:37:10 +01:00
Jakob Unterwurzacher
02693912e5 tests: convert remaining wget calls to dl-linux-tarball.bash helper
Makes the scripts work when wget is not available (macos)
2018-03-07 09:45:20 +01:00
Jakob Unterwurzacher
d09a51b80a macos: tests: use curl of wget is not available 2018-03-07 09:40:48 +01:00
Jakob Unterwurzacher
98f735ff6e tests: drop "-z" from fusermount to catch forgotten fds
macos does not have lazy unmount, so let's not use it
on linux either.
If the unmount fails, run "lsof" to find the open file.

Also fix the first bug we found this way.
2018-03-06 21:28:09 +01:00
Jakob Unterwurzacher
18d4159d18 macos: fix fd leak in reverse tests
Causes "Resource busy" unmount failures on macos
2018-03-05 23:21:08 +01:00
Jakob Unterwurzacher
1789a5ea5b tests: matrix_test: skip cases when without_openssl is set
Fixes test-without-openssl.bash.
2018-03-05 23:11:27 +01:00
Jakob Unterwurzacher
35192abb57 test_helpers: add missing newline 2018-03-05 23:06:27 +01:00
Jakob Unterwurzacher
870779ab1d macos: doTestUtimesNano: skip UTIME_OMIT and nanoseconds testcases
Not supported on macos.

Beef up the first test case a little by using different second
values.
2018-03-05 22:52:05 +01:00
Jakob Unterwurzacher
426b9536df tests: TestUtimesNano: replace ugly compareUtimes wrapper 2018-03-05 22:22:35 +01:00
Jakob Unterwurzacher
3064d72b97 tests: fix a few fd leaks
We relied on the finalizer to close a few fds.
For some reason, this did not cause problems on Linux,
but on MacOS, it causes unmount failures:

umount(/private/tmp/gocryptfs-test-parent/194654785/default-plain): Resource busy -- try 'diskutil unmount'
2018-03-05 22:00:59 +01:00
Jakob Unterwurzacher
aa65091bb9 macos: skip TestUtimesNanoSymlink early
Gets rid of the touch error message upon running the tests.
2018-03-05 21:36:16 +01:00
Jakob Unterwurzacher
b820fa691d macos: adjust TestTooLongSymlink length for darwin
Limit is much lower than on linux
2018-03-05 21:23:57 +01:00
Jakob Unterwurzacher
29496baa70 MacOS: skip TestUtimesNanoSymlink and TestUtimesNanoFd
These cannot work on MacOS.
2018-02-28 20:48:33 +01:00
Jakob Unterwurzacher
48d5f10c79 test_helpers: use an intermediate pipe for subprocess stdout
To Go test logic waits for stderr and stdout to close, so
when we share it with a subprocess, it will wait for it to
exit as well.

We don't want the tests to hang when the unmount fails.

Seen on MacOS as reported at
https://github.com/rfjakob/gocryptfs/issues/213
2018-02-28 20:03:54 +01:00
Jakob Unterwurzacher
3b8f5cbb17 readpassword: convert from string to []byte
This will allows us to overwrite the password
with zeros once we are done with it.

https://github.com/rfjakob/gocryptfs/issues/211
2018-02-18 14:26:54 +01:00
Jakob Unterwurzacher
991708af01 Documentation: add extractloop example output 2018-01-21 20:04:37 +01:00
Jakob Unterwurzacher
8951eb2472 fusefronted: add PlaintextNames special-cases for Create & Rename
gocryptfs.longname.XXX files were considered magic in PlaintextNames
mode, which was wrong.

Fix that and add tests.

Fixes https://github.com/rfjakob/gocryptfs/issues/174
2018-01-17 00:25:36 +01:00
Sebastian Lackner
a24342f656 fusefrontend: Handle PlaintextNames mode in Link
In PlaintextNames mode the "gocryptfs.longname." prefix does not have any
special meaning.

https://github.com/rfjakob/gocryptfs/issues/174
2017-12-25 15:07:37 +01:00
Jakob Unterwurzacher
87736eb833 fusefrontend_reverse: secure Access against symlink races (somewhat)
Unfortunately, faccessat in Linux ignores AT_SYMLINK_NOFOLLOW,
so this is not completely atomic.

Given that the information you get from access is not very
interesting, it seems good enough.

https://github.com/rfjakob/gocryptfs/issues/165
2017-12-07 00:11:35 +01:00
Jakob Unterwurzacher
6bd2da89d3 tets_helpers: handle t=nil in InitFS
The reverse tests call InitFS with t=nil. By
calling panic we get a better error message instead
of a generic nil pointer dereference.
2017-12-06 23:03:37 +01:00
Sebastian Lackner
614745ee57 fusefrontend: allow_other: close race between mkdir and chown
Fixes the same problem as described in 72b975867a,
except for directories instead of device nodes.
2017-11-29 13:28:04 +01:00
Sebastian Lackner
2591900b69 fusefrontend: Handle PlaintextNames mode in Unlink
In PlaintextNames mode the "gocryptfs.longname." prefix does not have any
special meaning. We should not attempt to delete any .name files.

Partially fixes https://github.com/rfjakob/gocryptfs/issues/174
2017-11-28 09:28:06 +01:00
Sebastian Lackner
3f68b0c09a fusefrontend: Handle PlaintextNames mode in Mknod
In PlaintextNames mode the "gocryptfs.longname." prefix does not have any
special meaning. We should not attempt to read the directory IV or to
create special .name files.

Partially fixes https://github.com/rfjakob/gocryptfs/issues/174
2017-11-28 09:28:06 +01:00
Jakob Unterwurzacher
72b975867a fusefronted: allow_other: close race between mknod and chown
If the user manages to replace the directory with
a symlink at just the right time, we could be tricked
into chown'ing the wrong file.

This change fixes the race by using fchownat, which
unfortunately is not available on darwin, hence a compat
wrapper is added.

Scenario, as described by @slackner at
https://github.com/rfjakob/gocryptfs/issues/177 :

1. Create a forward mount point with `plaintextnames` enabled
2. Mount as root user with `allow_other`
3. For testing purposes create a file `/tmp/file_owned_by_root`
   which is owned by the root user
4. As a regular user run inside of the GoCryptFS mount:

```
mkdir tempdir
mknod tempdir/file_owned_by_root p &
mv tempdir tempdir2
ln -s /tmp tempdir
```

When the steps are done fast enough and in the right order
(run in a loop!), the device file will be created in
`tempdir`, but the `lchown` will be executed by following
the symlink. As a result, the ownership of the file located
at `/tmp/file_owned_by_root` will be changed.
2017-11-27 21:04:45 +01:00
Jakob Unterwurzacher
1bb47b6796 reverse: reject too-long symlink target reads with ENAMETOOLONG
If the symlink target gets too long due to base64 encoding, we should
return ENAMETOOLONG instead of having the kernel reject the data and
returning an I/O error to the user.

Fixes https://github.com/rfjakob/gocryptfs/issues/167
2017-11-26 21:37:12 +01:00
Sebastian Lackner
90687215a4 fusefrontend_reverse: Do not mix up cache information for different directories
Fixes https://github.com/rfjakob/gocryptfs/issues/168

Steps to reproduce the problem:

* Create a regular reverse mount point
* Create files with the same very long name in multiple directories - so far
  everything works as expected, and it will appear with a different name each
  time, for example, gocryptfs.longname.A in directory A and
  gocryptfs.longname.B in directory B
* Try to access a path with A/gocryptfs.longname.B or B/gocryptfs.longname.A -
  this should fail, but it actually works.

The problem is that the longname cache only uses the path as key and not the
dir or divIV. Assume an attacker can directly interact with a reverse mount and
knows the relation longname path -> unencoded path in one directory, it allows
to test if the same unencoded filename appears in any other directory.
2017-11-25 16:20:48 +01:00
Sebastian Lackner
9f56b33e0c fusefrontend: Fix longname handling for renames with existing target
Fixes https://github.com/rfjakob/gocryptfs/issues/170

Steps to reproduce the problem:

* Create a regular forward mount point
* Create a file with a shortname and one with a long filename
* Try to run 'mv <shortname> <longname>'

This should actually work and replace the existing file, but instead it
fails with:

    mv: cannot move '<shortname>' to '<longname>': File exists

The problem is the creation of the .name file. If the target already exists
we can safely ignore the EEXIST error and just keep the existing .name file.
2017-11-25 16:19:09 +01:00