Filesystems incorrectly escape backslashes in files and folders

[JSCU-CNI]

Some filesystems seem to incorrectly escape backslashes in files and folders. This is likely unnecessary since 763fddc introduced the alt_separator behaviour.

Given the /example folder below, plugins like walkfs and tools like target-shell will break when encountering a filesystem entry with a backslash.

$ tree /example
/example
├── backslash\folder
│   └── file.txt
└── back\slash.txt

# example on ext4 filesystem
$ target-query -f walkfs example.vmdk
...
dissect.target.exceptions.FileNotFoundError: /example/backslash\folder

At least four filesystem implementations use this form of escaping:

• dissect.ntfs (https://github.com/fox-it/dissect.ntfs/blob/main/dissect/ntfs/mft.py#L76)
• dissect.xfs (https://github.com/fox-it/dissect.xfs/blob/main/dissect/xfs/xfs.py#L58)
• dissect.extfs (https://github.com/fox-it/dissect.extfs/blob/main/dissect/extfs/extfs.py#L113)
• dissect.fat (https://github.com/fox-it/dissect.fat/blob/main/dissect/fat/fat.py#L94)
• and perhaps others (https://github.com/search?q=org%3Afox-it%20replace(%22%5C%5C&type=code)

[Schamper]

Good catch. Will you create PRs yourself in the relevant places? Otherwise I'll make a start. I believe it's mostly an issue for the Unix filesystems, but will include the Windows ones too.

[JSCU-CNI]

Could you make a start?

[Schamper]

I believe these are it. Both dissect.ffs and dissect.vmfs already did this correctly, likely because I realized by then it wasn't actually correct, but never got around to fixing it in the other places :)

The changes in dissect.ntfs and dissect.fat are technically not required, but mostly made to be closer to the happy path, which may save a CPU cycle or two.

[Schamper]

Everything is now merged so this should be fixed. Let me know if this can be closed!

[JSCU-CNI]

Thanks for the quick fix. Can confirm this issue is resolved with the latest dev releases.