Commit Graph

109 Commits

Author SHA1 Message Date
Jakob Unterwurzacher
4674bac838 v2api/reverse: implement Lookup for gocryptfs.conf & gocryptfs.diriv 2020-08-02 13:25:53 +02:00
Jakob Unterwurzacher
47d8f56b7f v2api/reverse: add missing decryptPath call openBackingDir 2020-08-01 23:06:35 +02:00
Jakob Unterwurzacher
6c26cda531 v2api/reverse: implement Readdir 2020-08-01 22:28:25 +02:00
Jakob Unterwurzacher
f54d21c384 v2api/reverse: implement Lookup & Getattr 2020-08-01 21:14:33 +02:00
Jakob Unterwurzacher
18b3bdb158 v2api/reverse: start fusefrontend_reverse v2 API implementation 2020-08-01 21:14:17 +02:00
Jakob Unterwurzacher
13dc7657ba v2api/reverse: move old fusefrontend_reverse out of the way
fusefrontend_reverse -> fusefrontend_reverse_v1api
2020-08-01 21:14:10 +02:00
Jakob Unterwurzacher
dd3d8c100b fusefrontend_reverse: collapse getFileType 2020-08-01 20:28:06 +02:00
Jakob Unterwurzacher
2aad58f9ec v2api (go-fuse v2 api): initial noop implementation
Compiles and mounts but does nothing useful.
2020-06-21 12:01:24 +02:00
Jakob Unterwurzacher
ec74d1d2f4 Update go-fuse import path to github.com/hanwen/go-fuse/v2
We need
fd7328faf9
to fix a crash reported in https://github.com/rfjakob/gocryptfs/issues/430 :

  2019/10/30 17:14:16 Unknown opcode 2016
  panic: runtime error: invalid memory address or nil pointer dereference
  [signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x508d38]

This patch is only in the v2.x.x branch. Upgrade to v2, as the
old API is also supported there.

Running

  git grep hanwen/go-fuse | grep -v hanwen/go-fuse/v2

to check for forgotten references comes back clean.
2020-05-17 14:23:47 +02:00
Jakob Unterwurzacher
ead7008a08 Fix spelling mistakes found by misspell
https://github.com/client9/misspell
2020-05-10 00:25:49 +02:00
Jakob Unterwurzacher
16221facb9 ctlsock: create exported ctlsock client library
The former interal ctlsock server package is renamed
to ctlsocksrv.
2020-05-09 17:36:41 +02:00
Jakob Unterwurzacher
518771e4e2 fusefrontend_reverse: use inomap for inode number translation
Gets rid of static inode number value limitations.

Fixes https://github.com/rfjakob/gocryptfs/issues/457
2020-05-03 15:22:10 +02:00
Jakob Unterwurzacher
fe06e9f456 readpassword: delete CheckTrailingGarbage
CheckTrailingGarbage was called even when "-passfile" was
used, which is stupid, and causes false positives:

https://github.com/rfjakob/gocryptfs/issues/391
(false error "Received trailing garbage after the password"
when using -passfile in .bash_profile)

Instead of trying to improve the logic to handle that case
and make everything even more complicated, delete the function.

It is unclear if actually helps in some cases, and it definitely
harms as shown by the above bug report.
2019-04-08 20:18:45 +02:00
Jakob Unterwurzacher
fba9b2b995 reverse: don't show gocryptfs.conf if a custom config path was passed
GetAttr checks for this, but OpenDir did not.

https://github.com/rfjakob/gocryptfs/issues/385
2019-03-26 20:59:52 +01:00
Eduardo M KALINOWSKI
3bc100aeb3 reverse mode: support wildcard exclude (--exclude-wildcard)
This adds support for gitignore-like wildcards and exclude patters in
reverse mode. It (somewhat) fixes #273: no regexp support, but the
syntax should be powerful enough to satisfy most needs.

Also, since adding a lot of --exclude options can be tedious, it adds
the --exclude-from option to read patterns from a file (or files).
2019-03-26 20:56:37 +01:00
Jakob Unterwurzacher
3d6b2685fb Revert "syscallcompat: drop Faccessat AT_SYMLINK_NOFOLLOW helper"
Breaks mounting on MacOS: unix.Faccessat on Darwin does NOT (yet)
support AT_SYMLINK_NOFOLLOW. See d44fe89ba4 .

This reverts commit 0805a63df1.
2019-01-20 13:10:59 +01:00
Jakob Unterwurzacher
0805a63df1 syscallcompat: drop Faccessat AT_SYMLINK_NOFOLLOW helper
unix.Faccessat has added support for AT_SYMLINK_NOFOLLOW in July 2018,
bd9dbc187b (diff-341484dbbe3180cd7a31ef2ad2d679b6)
which means we no longer need our own helper.

Closes https://github.com/rfjakob/gocryptfs/issues/347
2019-01-20 12:59:59 +01:00
Sebastian Lackner
d8bb223dd3 fusefrontend_reverse: Delete leftover debug statement. 2019-01-15 22:07:37 +01:00
Sebastian Lackner
117dc3f2cc fusefrontend_reverse: Fix redeclaration of 'entries' variable.
Go version go1.10.7 linux/amd64 complains with:

 internal/fusefrontend_reverse/rfs.go:333: declaration of "entries" shadows
 declaration at internal/fusefrontend_reverse/rfs.go:327
2019-01-04 20:11:45 +01:00
Jakob Unterwurzacher
6b94f5ef51 reverse mode: -exclude: filter out excluded .name files
Fixes https://github.com/rfjakob/gocryptfs/issues/286 :

While the actual file is properly excluded, the * .name file is still leaked in the directory listing:

```
drwxr-xr-x 2 sebastian sebastian 4,0K Dez 17 14:58 .
drwxr-xr-x 7 sebastian sebastian 4,0K Dez 17 14:45 ..
-r-------- 1 sebastian sebastian  408 Dez 17 14:56 gocryptfs.conf
-r--r--r-- 1 sebastian sebastian   16 Dez 17 14:58 gocryptfs.diriv
-r--r--r-- 1 sebastian sebastian  320 Dez 17 14:58 gocryptfs.longname.3vZ_r3eDPb1_fL3j5VA4rd_bcKWLKT9eaxOVIGK5HFA.name
```
2019-01-04 17:59:00 +01:00
Jakob Unterwurzacher
75a3e2c2ee reverse mode: fix "-exclude" in "-plaintextnames" dir listings
Excluded files showed up in directory listing like this:

 drwxr-xr-x 2 sebastian sebastian 4,0K Dez 17 14:48 .
 drwxr-xr-x 7 sebastian sebastian 4,0K Dez 17 14:45 ..
 -????????? ? ?         ?            ?            ? abcd
 -r-------- 1 sebastian sebastian  366 Dez 17 14:45 gocryptfs.conf

Fixes https://github.com/rfjakob/gocryptfs/issues/285
2019-01-04 17:36:06 +01:00
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
9ec9d0c49c syscallcompat: untangle OpenNofollow and rename to OpenDirNofollow
The function used to do two things:

1) Walk the directory tree in a manner safe from symlink attacks
2) Open the final component in the mode requested by the caller

This change drops (2), which was only used once, and lets the caller
handle it. This simplifies the function and makes it fit for reuse in
forward mode in openBackingPath(), and for using O_PATH on Linux.
2018-09-08 17:41:17 +02:00
Jakob Unterwurzacher
7a02f71fc2 fusefrontend_reverse: reject excludes for the root directory ""
This is most likely a mistake by the user. Reject it.
2018-08-15 12:28:29 +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
bde7ba57b0 darwin does not have PATH_MAX
Define our own, with the value from Linux.
2018-06-08 00:47:48 +02:00
Jakob Unterwurzacher
719693ec5d fusefrontend[_reverse]: move crypto init up to caller
Both fusefrontend and fusefrontend_reverse were doing
essentially the same thing, move it into main's
initFuseFrontend.

A side-effect is that we have a reference to cryptocore
in main, which will help with wiping the keys on exit
(https://github.com/rfjakob/gocryptfs/issues/211).
2018-02-18 11:21:58 +01:00
Jakob Unterwurzacher
9f8d0d8e57 gccgo: replace syscall.NAME_MAX with unix.NAME_MAX
For some reason the syscall.NAME_MAX constant does not exist
on gccgo, and it does not hurt us to use unix.NAME_MAX instead.

https://github.com/rfjakob/gocryptfs/issues/201
2018-02-01 23:50:11 +01:00
Jakob Unterwurzacher
a2677bce2a fusefrontend_reverse: use OpenNofollow in virtualFile.GetAttr
Makes it robust against symlink races.

Final piece, closes https://github.com/rfjakob/gocryptfs/issues/165
2018-01-17 21:36:38 +01:00
Jakob Unterwurzacher
959e1fc1e2 fusefrontend_reverse: use OpenNofollow in findLongnameParent
Protects findLongnameParent against symlink races.

Also add comments to several functions along the way.

Reported at https://github.com/rfjakob/gocryptfs/issues/165
2018-01-17 20:54:05 +01:00
Jakob Unterwurzacher
36ffd813cd Run go fmt 2018-01-16 23:18:53 +01:00
Sebastian Lackner
631974f9e0 fusefrontend_reverse: Use O_DIRECTORY in OpenDir implementation
Also get rid of the defer - it is not really necessary here.
2017-12-11 21:18:20 +01:00
Sebastian Lackner
96dc2ca709 fusefrontend_reverse: Reject access to device nodes in newFile function
Steps to reproduce:

* Create a regular reverse mount point
* Create a file "test" in the original directory
* Access the corresponding encrypted directory in the mount point (ls <encrypted dir>)
* Quickly delete the file in the original data - instead create a device node
* Access the file again, it will access the device node and attempt to read from it

Fixes https://github.com/rfjakob/gocryptfs/issues/187
2017-12-11 09:55:16 +01:00
Sebastian Lackner
3af51736f3 fusefrontend_reverse: Use openBackingDir in GetAttr
Also fixes 48bd59f388 - the directory FD should
also be closed in case of an error.
2017-12-07 23:36:11 +01:00
Sebastian Lackner
ad0f110191 fusefrontend_reverse: Use openBackingDir in Readlink 2017-12-07 23:36:11 +01:00
Jakob Unterwurzacher
48bd59f388 fusefrontend_reverse: fix fd leak in GetAttr
Fixes https://github.com/rfjakob/gocryptfs/issues/184
2017-12-07 09:01:12 +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
e042eb38fa fusefrontend_reverse: secure Readlink against symlink races
...by using Readlinkat.

Tracking ticket: https://github.com/rfjakob/gocryptfs/issues/165
2017-12-06 21:13:08 +01:00
Jakob Unterwurzacher
a3bdc2bf2b fusefrontend_reverse: secure GetAttr against symlink races
...by using the OpenNofollow helper & Fstatat.

Also introduce a helper to convert from unix.Stat_t to
syscall.Stat_t.

Tracking ticket: https://github.com/rfjakob/gocryptfs/issues/165
2017-12-06 00:06:31 +01:00
Jakob Unterwurzacher
926cb93b50 fusefrontend_reverse: secure OpenDir against symlink races
...by using the new OpenNofollow helper.

The benchmark shows a small but acceptable performance loss:

  $ ./benchmark-reverse.bash
  LS:  2.182
  CAT: 18.221

Tracking ticket: https://github.com/rfjakob/gocryptfs/issues/165
2017-12-05 23:14:12 +01:00
Jakob Unterwurzacher
441e796e70 fusefrontend_reverse: secure StatFs agains symlink races
...by ignoring the path that was passed in.

https://github.com/rfjakob/gocryptfs/issues/165
2017-12-02 21:36:07 +01:00
Jakob Unterwurzacher
316b916358 fusefrontend_reverse: secure Open against symlink races
...using the new syscallcompat.OpenNofollow helper.

This change secures Open() against symlink race attacks
as described in https://github.com/rfjakob/gocryptfs/issues/165
2017-12-02 21:07:56 +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
f80f19f589 fusefrontend_reverse: Add a missing Close() call 2017-11-22 23:42:49 +01:00
Jakob Unterwurzacher
4da245c69d fusefrontend_reverse: fix 176-byte names
A file with a name of exactly 176 bytes length caused this error:

  ls: cannot access ./tmp/dsg/sXSGJLTuZuW1FarwIkJs0w/b6mGjdxIRpaeanTo0rbh0A/QjMRrQZC_4WLhmHI1UOBcA/gocryptfs.longname.QV-UipdDXeUVdl05WruoEzBNPrQCfpu6OzJL0_QnDKY: No such file or directory
  ls: cannot access ./tmp/dsg/sXSGJLTuZuW1FarwIkJs0w/b6mGjdxIRpaeanTo0rbh0A/QjMRrQZC_4WLhmHI1UOBcA/gocryptfs.longname.QV-UipdDXeUVdl05WruoEzBNPrQCfpu6OzJL0_QnDKY.name: No such file or directory
  -????????? ? ?     ?             ?            ? gocryptfs.longname.QV-UipdDXeUVdl05WruoEzBNPrQCfpu6OzJL0_QnDKY
  -????????? ? ?     ?             ?            ? gocryptfs.longname.QV-UipdDXeUVdl05WruoEzBNPrQCfpu6OzJL0_QnDKY.name

Root cause was a wrong shortNameMax constant that failed to
account for the obligatory padding byte.

Fix the constant and also expand the TestLongnameStat test case
to test ALL file name lengths from 1-255 bytes.

Fixes https://github.com/rfjakob/gocryptfs/issues/143 .
2017-10-01 13:50:25 +02:00
Jakob Unterwurzacher
0c520845f3 main: purge masterkey from memory as soon as possible
Remove the "Masterkey" field from fusefrontend.Args because it
should not be stored longer than neccessary. Instead pass the
masterkey as a separate argument to the filesystem initializers.

Then overwrite it with zeros immediately so we don't have
to wait for garbage collection.

Note that the crypto implementation still stores at least a
masterkey-derived value, so this change makes it harder, but not
impossible, to extract the encryption keys from memory.

Suggested at https://github.com/rfjakob/gocryptfs/issues/137
2017-08-11 19:02:26 +02:00
Jakob Unterwurzacher
75ec94a87a nametransform: add Dir() function
Dir is like filepath.Dir but returns "" instead of ".".
This was already implemented in fusefrontend_reverse as saneDir().

We will need it in nametransform for the improved diriv caching.
2017-08-06 23:14:39 +02:00
Jakob Unterwurzacher
d12aa57715 fusefronted_reverse: fix ino collision between .name and .diriv files
A directory with a long name has two associated virtual files:
the .name file and the .diriv files.

These used to get the same inode number:

  $ ls -di1  * */*
             33313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw
  1000000000033313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw/gocryptfs.diriv
  1000000000033313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw.name

With this change we use another prefix (2 instead of 1) for .name files.

  $ ls -di1 * */*
             33313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw
  1000000000033313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw/gocryptfs.diriv
  2000000000033313535 gocryptfs.longname.2togDFouca9mrTwtfF1RNW5DZRAQY8alaR7wO_Xd5Zw.name
2017-07-29 16:15:49 +02:00
Jakob Unterwurzacher
d5133ca5ac fusefrontend_reverse: return ENOENT for undecryptable names
This was working until DecryptName switched to returning
EBADMSG instead of EINVAL.

Add a test to catch the regression next time.
2017-07-27 20:31:22 +02:00