Commit Graph

37 Commits

Author SHA1 Message Date
Sebastian Lackner
a97d14c42d syscallcompat: fetch supplementary groups for OpenatUser & friends
Handled the same way in GlusterFS, disorderfs, libfuse.
Fixes https://github.com/rfjakob/gocryptfs/issues/394
2019-05-01 17:52:07 +02:00
Sebastian Lackner
682e642cfa fusefrontend: Rework the Utimens handling on macOS.
For Linux, everything effectively stays the same. For both path-based and
fd-based Utimens() calls, we use unix.UtimesNanoAt(). To avoid introducing
a separate syscall wrapper for futimens() (as done in go-fuse, for example),
we instead use the /proc/self/fd - trick.

On macOS, this changes quite a lot:

* Path-based Utimens() calls were previously completely broken, since
  unix.UtimensNanoAt() ignores the passed file descriptor. Note that this
  cannot be fixed easily since there IS no appropriate syscall available on
  macOS prior to High Sierra (10.13). We emulate this case by using
  Fchdir() + setattrlist().

* Fd-based Utimens() calls were previously translated to f.GetAttr() (to
  fill any empty parameters) and syscall.Futimes(), which does not does
  support nanosecond precision. Both issues can be fixed by switching to
  fsetattrlist().

Fixes https://github.com/rfjakob/gocryptfs/issues/350
2019-01-16 20:55:20 +01:00
Jakob Unterwurzacher
a7d59032d3 syscallcompat: rework Fchmodat to FchmodatNofollow
We never want Fchmodat to follow symlinks, so follow what
Qemu does, and call our function FchmodatNofollow.
2019-01-14 21:54:16 +01:00
Sebastian Lackner
a9d8eb49ef syscallcompat: Drop Fstatat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
4134ff7570 syscallcompat: Drop Mkdirat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
7b0d56fe98 syscallcompat: Drop Symlinkat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
92110628ee syscallcompat: Drop Fchownat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
229a9da74b syscallcompat: Drop Unlinkat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
42bf6d1c68 syscallcompat: Drop Renameat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
da557702d7 syscallcompat: Drop Openat emulation on macOS. 2019-01-14 21:27:28 +01:00
Sebastian Lackner
efc280330c fusefrontend: -allow_other: Use SymlinkatUser in Symlink FUSE call.
Instead of manually adjusting the user after creating the symlink,
adjust effective permissions and let the kernel deal with it.

Related to https://github.com/rfjakob/gocryptfs/issues/338.
2019-01-12 21:22:58 +01:00
Sebastian Lackner
1fbe7798cf fusefrontend: -allow_other: Use MknodatUser in Mknod FUSE call.
Instead of manually adjusting the user and mode after creating the
device file, adjust effective permissions and let the kernel deal
with it.

Related to https://github.com/rfjakob/gocryptfs/issues/338.
2019-01-12 21:20:16 +01:00
Sebastian Lackner
a525e33eaa fusefrontend: -allow_other: Use MkdiratUser in Mkdir FUSE call.
Revert commit fcaca5fc94.

Instead of manually adjusting the user and mode after creating the
directory, adjust effective permissions and let the kernel deal with it.

Related to https://github.com/rfjakob/gocryptfs/issues/338.
2019-01-12 21:20:07 +01:00
Sebastian Lackner
03b9d65cce fusefrontend: -allow_other: Use OpenatUser in Create FUSE call.
Revert commit b22cc03c75.

Instead of manually adjusting the user and mode after creating the
file, adjust effective permissions and let the kernel deal with it.

Related to https://github.com/rfjakob/gocryptfs/issues/338.
2019-01-12 20:54:39 +01:00
Sebastian Lackner
4170ef00f3 syscallcompat: Implement workaround for Fchmodat with AT_SYMLINK_NOFOLLOW.
Fixes https://github.com/rfjakob/gocryptfs/issues/259
2019-01-07 23:07:53 +01:00
Jakob Unterwurzacher
737a2f2012 syscallcompat: untangle Openat flag check
Check for O_NWFOLLOW and O_EXCL separately to
make the logic clearer.
2018-09-22 19:38:47 +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
658cc4aebb syscallcompat: drop Fchmodat flags
These were silently ignored until now (!) but
are rejected by Go 1.11 stdlib.

Drop the flags so the tests work again, until
we figure out a better solution.

https://github.com/golang/go/issues/20130
2018-08-26 13:04:01 +02:00
Jakob Unterwurzacher
53f7e1a0f0 macos: fix O_DIRECT build failure
O_DIRECT has no direct equivalent on MacOS
(check out https://github.com/libuv/libuv/issues/1600 for details).

Just define it to zero there.
2018-07-04 09:04:00 +02:00
Jakob Unterwurzacher
70bcf58a9b syscallcompat: convert Getdents to fd input, add emulation
Now that we have Fstatat we can use it in Getdents to
get rid of the path name.

Also, add an emulated version of getdents for MacOS. This allows
to drop the !HaveGetdents special cases from fusefrontend.

Modify the getdents test to test both native getdents and the emulated
version.
2017-12-03 19:33:26 +01:00
Jakob Unterwurzacher
e33593d30d syscallcompat: add Fstatat + emulation + test
Fstatat has recently been added to x/sys/unix. Make
it available for use in gocryptfs.
2017-12-03 19:32:59 +01:00
Jakob Unterwurzacher
77191c3485 syscallcompat: use Unlinkat and Symlinkat from x/sys/unix
I'm unsure why I did not notice this earlier, but the
syscall wrappers provided by x/sys/unix seem to do just
fine.

Drop our own version.
2017-12-02 18:36:18 +01:00
Jakob Unterwurzacher
e97c23e083 syscallcompat: check that we get NOFOLLOW wherever possible
...and fix the instances where the AT_SYMLINK_NOFOLLOW /
O_NOFOLLOW / O_EXCL flag was missing.
2017-11-30 19:40:53 +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
0162392a28 fusefrontend: Use Fchmodat to implement Chmod 2017-11-29 12:55:41 +01:00
Sebastian Lackner
0f44c617d0 syscallcompat: Introduce unlinkat syscall with flags argument 2017-11-29 12:41:23 +01:00
Sebastian Lackner
5a56810603 fusefrontend: Use the Symlinkat syscall for longname handling 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
a4563e21ec main, syscallcompat: use Dup3 instead of Dup2
Dup2 is not implemented on linux/arm64.

Fixes https://github.com/rfjakob/gocryptfs/issues/121 .

Also adds cross-compilation to CI.
2017-06-18 15:43:22 +02:00
Jakob Unterwurzacher
a4956fa6bf A few more lint fixes 2016-10-04 23:30:05 +02:00
Valient Gough
b764917cd5 lint fixes 2016-10-04 23:18:33 +02:00
Jakob Unterwurzacher
e8a234f658 Add godoc comments to all internal packages 2016-07-06 21:51:25 +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
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