VFS Implementation and user authentication

[Luke Kenneth Casson Leighton]

> But I so would like it if Unix systems supported SIDs or something like
> that. It would make mergers easier (I'm on my 6th bank merger now).

that _is_ technically possible.  i talked to steven tweedie and alan cox
at ukuug 2000.

apparently, both the linux nfs server _and_ the coda filesystem have
callbacks from kernel-space to user-space on certain functions.

e.g open(), rename(), unlink(), mkdir(), rmdir().

in this way, the interpretation of security can be performed.  in
user-space, the security blob will need to be obtained, a call to SURS
will be required, as will a call to se_access_check() for the type of
operation being carried out.