Module access_policy 

Layered access validation for proxy operations.

Every hardware access must be permitted by every layer: actual resource bounds, the immutable target ceiling, the exact session allowlist, and per-operation structural validation (width, alignment, and overflow). Rejection at any layer denies the access without touching hardware.

Structs

AccessPolicy

The validated policy engine for one session.

AccessRule

One exact session allowlist rule. Wildcards do not exist: a rule matches exactly one resource, offset, width, and access class.

MmioResource

Description of a resource offered by the parent node. Descriptions never contain physical addresses or raw handles.

ProtocolCeiling

Target ceiling policy for a protocol-backed resource (GPIO, I2C, SPI).

ResourceCeiling

Immutable per-resource read ceiling. A resource with no ceiling entry permits nothing.

WritableRegister

Target ceiling specification for one writable register.

WritePrecondition

A precondition required or checked before executing a write.

Enums

AccessClass

Access classes distinguished by policy. A grant for one class never authorizes another: a one-shot read grant does not authorize polling.

Denial

Why an access or allowlist rule was rejected. Reasons stay machine-readable; they must never exist only in a human detail string.

ResourceKind

The kind of hardware resource offered.

SessionMode

Session mode. A read-only session can never issue a write; a mutating session additionally requires the exclusive mutation lease.

Constants

WIDTH32

The only MMIO access width supported by the V1 wire contract, in bytes.

Type Aliases

ResourceId

Identifies a resource within one proxy instance.