Splash

On Name, Value, Identity, and Authority

Name

— Designation

Value

— Information

Identity

— Time

Authority

— Permission

Value associated with identity is referred to as state
- Mutable objects mix of identity and value
- Refs in Clojure separate and map from identity to value
Capabilities are names that designate authority and identity
Namespaces map name to identity

Security

Security problems stem from the improper coupling of name and authority.
- Commonly, a name designates too much authority, violating POLA and creating a security risk
- When identity and authority are designated by seperate names, the program is susceptable to a confused deputy attack

Concurrency

Concurrency problems stem from the improper coupling of identity and value

A Proposed Solution

When a function is called, curry in each argument by calling a curry_arg generic function. curry_arg for pure-value types would be equivalent to traditional currying. This would be implemented in some sort of :value specializer, so functions operating on Refs could have direct access.

For IRefs, curry_arg curries in the current value of the IRef.

For ARefs, curry_arg curries in the value of the ARef, if and only if the function is in its permitted set. Otherwise, it curries in itself. Another form of the specializer could simply fail if the value could not be unrapped. This version could be used on primitives such as prim_op_object_get_slot to protect access to the direct capability inside the ARef. (Problem: But then how does the curry_arg function access data inside the ARef?)

A membrane-like could be implemented in a subclass of ARef by wrapping the returned value in an ARef with the same permitted set.
Problem: This only works when types are homogeneous and the same functions are available
Problem: If the argument passing this type is not the first, the unwrapped return value would be passed through the functions that may have been added by the more inner arguments' curry_arg. Malicious code could create a type specializing curry_arg and capture this data