support encfs4win

[kkeane]

This is a companion to #1074

This issue affects the Windows version of encfs (encfsmp)

Brief description:

I suspect that this might be related to a per-user drive letter vs. a systemwide drive letter.

I have some important information stored on an encfs-encrypted drive letter. The Windows tool to mount such drives is encfsmp (http://encfsmp.sourceforge.net/) Drive letters mounted by encfsmp are not visible in /mnt/. Due to the nature of data I store encrypted, this is a show stopper for me. Note: the Linux version of encfs also does not work; I will enter a separate problem report for that.

• Expected results

• In Windows, run encfsmp to mount an encrypted drive as drive letter K: My other drive letters are C: and E:

• In Explorer, verify that the K: drive exists and is accessible.

• ls /mnt should show
  c e k

• Actual results (with terminal output if applicable)

  ls /mnt
  c e

• Your Windows build number
  14393

• Steps / All commands required to reproduce the error from a brand new installation

• Install encfsmp from http://encfsmp.sourceforge.net/

• Create an encrypted file system (Note: in my situation, the file system was originally created on a Linux system, and copied to the Windows system) and add some files.

• Add the encrypted file system to encfsmp as a mount named "MyVolumeName"

• Mount an encrypted file system. The command line I use is:
  "C:\Program Files\EncFSMP\EncFSMP.exe" mount -m MyVolumeName

• Start bash

• run ls /mnt

• Strace of the failing command
  N/A

• Required packages and commands to install
  On Windows: encfsmp.exe from http://encfsmp.sourceforge.net/

See our contributing instructions for assistance.

[aseering]

Thanks @kkeane for posting! My understanding (though someone from Microsoft can correct me) is that WSL currently only supports NTFS drives. So it shares the same root cause as #530 , #801 , and #802 .

For what it's worth, if I have to work with sensitive data within WSL, I use a BitLocker-encrypted NTFS volume; it seems to work fine. I realize that doesn't cover all use cases for encrypted volumes, but it works well for me.

[kkeane]

You are right, it appears to be the same underlying issue.

Bitlocker is not an option for me since I need cross-platform support. Also, encfs encrypts directories and files individually, while Bitlocker encrypts volumes. For a Bitlocker-type application, I use Veracrypt.

[tara-raj]

Please try the instructions on mounting a drive here. You can manually mount your drive this way

[linuxturtle]

Mounting with drvfs works using encfsmp, but with encfs-4win, attempting the mount produces an error :'( :

mount: /mnt/p: wrong fs type, bad option, bad superblock on P:, missing codepage or helper program, or other error.

[therealkenc]

Presume envfs-4win is this.

Interested parties can try new(ish) 9p filesystem via drvfs on WSL2 and see if it is better. If not, sharing the windows-drive via cifs sometimes pushes through. Failing-failing that, FUSE sshfs on the WSL2 side with Windows openssh server on the other side nearly always pushes though, because it hits a fraction of the filesystem surface.