ambient-authority

In capability-based security context, ambient authority means anything a program can do that interacts with the outside world that isn't represented by a handle.

This crate defines a function [ambient_authority] which returns a value of type [AmbientAuthority], which is an empty type used in function signatures to declare that they use ambient authority.

The convention for a crate to declare that its API avoids ambient authority is: - If the crate wishes to have functions which use ambient authority, adding an [AmbientAuthority] argument to them, along with a # Ambient Authority section in their documentation comments explaining their use of ambient authority, and re-exporting the [ambient_authority] function and AmbientAuthority type from this crate.

• Ensure that all other pub functions avoid using ambient authority, including mutable static state such as static Atomic, Cell, RefCell, Mutex, RwLock, or similar state, including once_cell or lazy_static state with initialization that uses ambient authority.

One of the cool things about capability-oriented APIs is that programs don't need to be pure to take advantage of them. That said, for programs which do which to aim for purity, this repository has a clippy configuration which can help: - Manually ensure that all immediate dependencies follow the above convention. - Copy the [clippy.toml] file into the top level source directory, add #![deny(clippy::disallowed_method)] to the root module (main.rs or lib.rs), and run cargo +nightly clippy or equivalent.