Commit Graph

37 Commits

Author SHA1 Message Date
Jakob Unterwurzacher
87a6bb370a nametransform: fix math.MaxInt build failure on older Go
Failure is:

  # github.com/rfjakob/gocryptfs/v2/internal/nametransform
  internal/nametransform/names.go:47:33: undefined: math.MaxInt

math.MaxInt was only introduced in Go 1.17. Use MaxInt32 instead,
which is good enough, even on amd64. It only has to be larger than
any name we might encounter.
2021-10-21 16:44:05 +02:00
Jakob Unterwurzacher
dc32710045 nametransform: add longNameMax parameter
Determines when to start hashing long names instead
of hardcoded 255. Will be used to alleviate "name too long"
issues some users see on cloud storage.

https://github.com/rfjakob/gocryptfs/issues/499
2021-10-21 14:55:30 +02:00
Jakob Unterwurzacher
69d88505fd go mod: declare module version v2
Our git version is v2+ for some time now, but go.mod
still declared v1. Hopefully making both match makes
https://pkg.go.dev/github.com/rfjakob/gocryptfs/v2 work.

All the import paths have been fixed like this:

  find . -name \*.go | xargs sed -i s%github.com/rfjakob/gocryptfs/%github.com/rfjakob/gocryptfs/v2/%
2021-08-23 15:05:15 +02:00
Jakob Unterwurzacher
195d9d18a9 Implement -deterministic-names: extended -zerodiriv
-deterministc-names uses all-zero dirivs but does not write
them to disk anymore.
2021-08-20 10:58:42 +02:00
Jakob Unterwurzacher
689b74835b nametransform: gather badname functions in badname.go 2021-06-21 12:10:04 +02:00
Jakob Unterwurzacher
2efef1e270 nametransform: delete NameTransformer interface
Useless layer of indirection.
2021-06-21 11:53:33 +02:00
Jakob Unterwurzacher
c5d8fa83ae nametransform: pass badname patterns via New
This means we can unexport the field.
2021-06-20 19:09:46 +02:00
DerDonut
a611810ff4 Badname file content access
This proposal is the counterpart of the modifications from the `-badname`
parameter. It modifies the plain -> cipher mapping for filenames when using
`-badname` parameter. The new function `EncryptAndHashBadName` tries to find a
cipher filename for the given plain name with the following steps:

1. If `badname` is disabled or direct mapping is successful: Map directly
(default and current behaviour)

2. If a file with badname flag has a valid cipher file, this is returned
(=File just ends with the badname flag)

3. If a file with a badname flag exists where only the badname flag was added,
this is returned (=File cipher name could not be decrypted by function
`DecryptName` and just the badname flag was added)

4. Search for all files which cipher file name extists when cropping more and
more characters from the end. If only 1 file is found, return this

5. Return an error otherwise

This allows file access in the file browsers but most important it allows that
you rename files with undecryptable cipher names in the plain directories.
Renaming those files will then generate a proper cipher filename One
backdraft: When mounting the cipher dir with -badname parameter, you can never
create (or rename to) files whose file name ends with the badname file flag
(at the moment this is " GOCRYPTFS_BAD_NAME"). This will cause an error.

I modified the CLI test function to cover additional test cases. Test [Case
7](https://github.com/DerDonut/gocryptfs/blob/badnamecontent/tests/cli/cli_test.go#L712)
cannot be performed since the cli tests are executed in panic mode. The
testing is stopped on error. Since the function`DecryptName` produces internal
errors when hitting non-decryptable file names, this test was omitted.

This implementation is a proposal where I tried to change the minimum amount
of existing code. Another possibility would be instead of creating the new
function `EncryptAndHashBadName` to modify the signature of the existing
function `EncryptAndHashName(name string, iv []byte)` to
`EncryptAndHashName(name string, iv []byte, dirfd int)` and integrate the
functionality into this function directly. You may allow calling with dirfd=-1
or other invalid values an then performing the current functionality.
2021-06-20 18:09:21 +02:00
Jakob Unterwurzacher
04858ddd22 nametransform: check name validity on encryption
xfstests generic/523 discovered that we allowed to set
xattrs with "/" in the name, but did not allow to read
them later.

With this change we do not allow to set them in the first
place.
2021-06-02 14:29:48 +02:00
Jakob Unterwurzacher
84ed139cd2 v2api/reverse: implement Lookup for longname 2020-08-02 19:33:12 +02:00
Jakob Unterwurzacher
261cf12829 badname: stop trying to decrypt at length 22
At least 16 bytes due to AES --> at least 22 characters in base64
2020-06-06 12:49:45 +02:00
DerDonut
a8230d271f Added auto decryption of invalid file names
Changed invalid file decoding and decryption. Function
DecryptName now shortens the filename until the filename is
decodable and decryptable. Will work with valid **and**
invalid Base64URL delimiter (valid delimiter [0-9a-zA-z_\\-].
If the filename is not decryptable at all, it returns the
original cipher name with flag suffix Changed cli tests to
generate decryptable and undecryptable file names with correct
encrypted content. Replacing #474, extends #393
2020-06-06 12:20:31 +02:00
Jakob Unterwurzacher
f6b1c680b3 nametransform: update comment & simplify tests
The comment still mentioned CBC, which has been removed
a long time ago.

The test definition can be rewritten using slice literals,
saving sume stuttering.
2020-04-18 16:14:48 +02:00
orcas
9ec042f2f6 Show undecryptable filenames if they match supplied glob
Resolves https://github.com/rfjakob/gocryptfs/issues/393
2020-02-28 22:17:59 +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
19cb6d046a nametransform: reject names longer than 255 chars
Looks like we allowed creating longer names by accident.
Fix that, and add a test that verifies it.
2019-02-17 17:05:05 +01:00
Jakob Unterwurzacher
4f66d66755 fusefrontend: add dirCache 2019-01-03 15:31:13 +01:00
Jakob Unterwurzacher
2b12bba274 fusefronted: make EncryptPath symlink-safe
Finally allows us to delete EncryptPathDirIV.
2019-01-02 21:45:40 +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
Sebastian Lackner
c547673529 nametransform: Return error if decrypted name is '.' or '..' 2017-11-22 23:42:08 +01:00
Jakob Unterwurzacher
5190cc09bb nametransform: move diriv cache into it's own package
Needs some space to grow.

renamed:    internal/nametransform/diriv_cache.go -> internal/nametransform/dirivcache/dirivcache.go
2017-08-06 21:59:15 +02:00
Jakob Unterwurzacher
e827763f2e nametransform: harden name decryption against invalid input
This fixes a few issues I have found reviewing the code:

1) Limit the amount of data ReadLongName() will read. Previously,
you could send gocryptfs into out-of-memory by symlinking
gocryptfs.diriv to /dev/zero.

2) Handle the empty input case in unPad16() by returning an
error. Previously, it would panic with an out-of-bounds array
read. It is unclear to me if this could actually be triggered.

3) Reject empty names after base64-decoding in DecryptName().
An empty name crashes emeCipher.Decrypt().
It is unclear to me if B64.DecodeString() can actually return
a non-error empty result, but let's guard against it anyway.
2017-05-23 21:26:38 +02:00
Jakob Unterwurzacher
26881538e1 nametranform, fusefrontend: better errors on invalid names
nametransform.DecryptName() now always returns syscall.EBADMSG if
the name was invalid.

fusefrontend.OpenDir error messages have been normalized.
2017-05-07 20:58:27 +02:00
Jakob Unterwurzacher
445b5019e3 nametransform: fix Raw64 not affecting symlink targets
The symlink functions incorrectly hardcoded the padded
base64 variant.
2017-03-05 22:59:25 +01:00
Jakob Unterwurzacher
966308eeb7 Drop Go 1.4 compatability code everywhere
Yields a nice reduction in code size.
2017-03-05 17:44:14 +01:00
Jakob Unterwurzacher
e032539e2c cryptocore: use eme v1.1 interface
Version 1.1 of the EME package (github.com/rfjakob/eme) added
a more convenient interface. Use it.

Note that you have to upgrade your EME package (go get -u)!
2017-03-05 13:58:24 +01:00
Jakob Unterwurzacher
d15122d3d6 Add Go 1.4 compatibility layer for raw64
Using raw64 will not work, but at least it will compile.
2016-11-01 19:25:59 +01:00
Jakob Unterwurzacher
2b991c9743 Add support for unpadded base64 filenames, "-raw64"
Through base64.RawURLEncoding.

New command-line parameter "-raw64".
2016-11-01 18:43:22 +01:00
Valient Gough
b764917cd5 lint fixes 2016-10-04 23:18:33 +02:00
Jakob Unterwurzacher
28838a489d nametransform: downgrade invalid length warning
This happens all the time in reverse mode when somebody stats
an encrypted symlink target.
2016-09-25 19:50:16 +02:00
Jakob Unterwurzacher
c7b3150afc nametransform: delete unused function DecryptPathDirIV 2016-09-25 18:56:23 +02:00
Jakob Unterwurzacher
b883dd10a6 reverse: add symlink encryption and Readlink support 2016-09-25 18:01:24 +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
e8a234f658 Add godoc comments to all internal packages 2016-07-06 21:51:25 +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
3d59a72ba9 Drop deprecated "-emenames" option
The EMENames feature flag is already mandatory, dropping the command
line option is the final step.
2016-06-23 21:56:50 +02:00
Jakob Unterwurzacher
7e92ebe16a Rename nametransform, contentenc source files
Let's have shorter names, and merge *_api.go into the "main"
file.

No code changes.
2016-06-16 19:02:47 +02:00