This crate is meant to solve #315 by giving a way to make sure that
a file or directory is only accessible by trusted users. I've tried
to explain carefully (in comments and documentation) what this crate
is doing and why, under the assumption that it will someday be read
by another person like me who does _not_ live and breathe unix file
permissions. The crate is still missing some key features, noted in
the TODO section.
It differs from the first version of the crate by taking a more
principled approach to directory checking: it emulates the path
lookup process (reading symlinks and all) one path change at a time,
thus ensuring that we check every directory which could enable
an untrusted user to get to our target file, _or_ which could
enable them to get to any symlink that would get them to the target
file.
The API is also slightly different: It separates the `Mistrust`
object (where you configure what you do or do not trust) from the
`Verifier` (where you set up a check that you want to perform on a
single object). Verifiers are set up to be a bit ephemeral,
so that it is hard to accidentally declare that _every_ object
is meant to be readable when you only mean that _some_ objects
may be readable.
trinity-1686a
Nick Mathewson