Pinning related APIs should treat names as paths and canonicalize them

[lmb]

Describe the feature you'd like supported

Pinning a map / program currently takes an uninterpreted string as the key for the ebpf pinning table. On Linux, pinning works on paths. So applications may rely on behaviour such as:

• . and .. special cases
• normalizing slashes when joining paths
• case sensitivity

Applications ported from Linux might therefore expect that foo/../map and foo/map or foo\map refer to the same object. They also might assume that foo/Map is distinct from foo/map.

If the goal is to expose objects via something similar to a file-system it would be great to start canonicalizing names now when the breakage potential is still low.

Proposed solution

Start interpreting pinning keys as paths, and canonicalize them according to Windows conventions.

Additional context

No response

[shankarseal]

@dthaler suggests using https://learn.microsoft.com/en-us/windows/win32/api/pathcch/nf-pathcch-pathcchcanonicalize in ebpfapi.dll. The path canonicalization needs to be only in user mode.

[lmb]

There is an extended version which supports flags: https://learn.microsoft.com/en-us/windows/win32/api/pathcch/nf-pathcch-pathalloccanonicalize once of which is PATHCCH_CANONICALIZE_SLASHES that seems relevant.