Re: Variant symlink filesystem

From: Austin S. Hemmelgarn
Date: Fri Mar 11 2016 - 15:39:27 EST

On 2016-03-11 15:24, Richard Weinberger wrote:
Am 11.03.2016 um 21:22 schrieb Cole:
If I remember correctly, when we were testing the fuse version, we hard coded
the path to see if that solved the problem, and the difference between
the env lookup
code and the hard coded path was almost the same, but substantially slower than
the native file system.

And where exactly as the performance problem?

Anyway, if you submit your filesystem also provide a decent use case for it. :-)

I don't know that this qualifies as a use case, but I've seen a number of capability based systems that have a similar concept they usually refer to as 'context dependent symbolic links'. In such cases, the resolution is usually based on what capabilities you posses, and is more of a mapping than a value expansion most of the time, but such usage could be emulated (albeit much less securely) with this. If this could be extended to expand other values (for example, process bit width, or SELinux context, or even what namespace the process is in), it could provide the same functionality almost as securely.