Setting/removing extended attributes on directories was partially fixed with
commit eff35e60b6. However, on most file systems
it is also possible to do these operations without read access (see tests).
Since we cannot open a write-access fd to a directory, we have to use the
/proc/self/fd trick (already used for ListXAttr) for the other operations aswell.
For simplicity, let's separate the Linux and Darwin code again (basically revert
commit f320b76fd1), and always use the
/proc/self/fd trick on Linux. On Darwin we use the best-effort approach with
openBackingFile() as a fallback.
More discussion about the available options is available in
https://github.com/rfjakob/gocryptfs/issues/308.
We are clean again.
Warnings were:
internal/fusefrontend/fs.go:443:14: should omit type string from declaration
of var cTarget; it will be inferred from the right-hand side
internal/fusefrontend/xattr.go:26:1: comment on exported method FS.GetXAttr
should be of the form "GetXAttr ..."
internal/syscallcompat/sys_common.go:9:7: exported const PATH_MAX should have
comment or be unexported
Reading system.posix_acl_access and system.posix_acl_default
should return EOPNOTSUPP to inform user-space that we do not
support ACLs.
xftestest essientially does
chacl -l | grep "Operation not supported"
to determine if the filesystem supports ACLs, and used to
wrongly believe that gocryptfs does.
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.
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.
We previously returned EPERM to prevent the kernel from
blacklisting our xattr support once we get an unsupported
flag, but this causes lots of trouble on MacOS:
Cannot save files from GUI apps, see
https://github.com/rfjakob/gocryptfs/issues/229
Returning ENOSYS triggers the dotfiles fallback on MacOS
and fixes the issue.
OpenDir and ListXAttr skip over corrupt entries,
readFileID treats files the are too small as empty.
This improves usability in the face of corruption,
but hides the problem in a log message instead of
putting it in the return code.
Create a channel to report these corruptions to fsck
so it can report them to the user.
Also update the manpage and the changelog with the -fsck option.
Closes https://github.com/rfjakob/gocryptfs/issues/191
