Lib.rs

Actor principals for AWS and AWS-like services.

Principals come in two "flavors": actor principals and policy principals. Policy principals are used in Aspen documents and have a source ("AWS", "CanonicalUser", "Federated", or "Service") and an associated value which may contain wildcards. These are implemented in the scratchstack-aspen crate.

On the service implementation side, actor principals (represented by [Principal] here) are exact, without wildcards. Beyond the core details, there are additional details attached to a principal actor that can be referenced in policy variables. For example, IAM users have a universally unique ID. If the /Sales/Bob user is deleted and re-created, these two users will have the same ARN but different unique IDs that can be referenced via the aws:userid condition key. These details are carried in [SessionData] structures apart from the [Principal] itself.