There's not a trait for it yet, but Smithy is designed to be auth agnostic so new auth traits can be added by anyone. There's a meta-trait called authDefinition[0] that you can apply to your own trait to indicate that it's an auth trait. With that your trait would show up anywhere else auth traits are found in the Smithy tooling. We're designing the code generators to be extensible enough that you could then fairly easily implement just the necessary bits.
[0]: https://awslabs.github.io/smithy/1.0/spec/core/auth-traits.h...