Skip to content

VirtualAudioDriverIntegration.md

Latest commit

 

History

History
83 lines (65 loc) · 3.4 KB

VirtualAudioDriverIntegration.md

File metadata and controls

83 lines (65 loc) · 3.4 KB
Raw

Integrating the Virtual Audio Driver

RilliyaVirtualAudio separates endpoint management from privileged driver installation. The Swift package provides validated value types and a store for the Rilliya driver. It does not install, sign, or load privileged code.

The clean-room Audio Server plug-in source is published with the Rilliya application under the Apache License 2.0. It uses Apple's public Core Audio plug-in interfaces and has no third-party runtime dependency.

Manage endpoints

The default store locates the installed Rilliya driver and updates its endpoint catalog through Core Audio. Each mutation reads the latest catalog first, so a stale process cannot silently overwrite a newer revision.

import RilliyaVirtualAudio

let store = VirtualAudioEndpointStore()

guard try await store.availability() == .available else {
  // Offer the host application's signed installer.
  return
}

let endpoint = try await store.create(
  VirtualAudioEndpointConfiguration(
    name: "Broadcast Mix",
    direction: .input,
    format: .stereo48kHz
  )
)

print(endpoint.deviceUIDs.visible)

An input endpoint exposes host-produced audio to other applications. An output endpoint accepts audio from other applications for the host to consume. Every endpoint also has a hidden bridge device used by the host. Persist the endpoint ID in workflows and derive current device UIDs from the returned endpoint; do not persist transient Core Audio object IDs.

Catalog replacement is a control-plane operation. The driver rejects it while any published device is running, so a host should pause dependent workflows before changing an endpoint's direction or format. Store errors preserve the failed operation and Core Audio status where applicable.

Ship the driver

A distributing application is responsible for the privileged boundary:

  1. Build the .driver bundle for every supported architecture and combine the executable into one Universal bundle.
  2. Sign the bundle with that distributor's own Developer ID Application identity and the hardened runtime.
  3. Place it at /Library/Audio/Plug-Ins/HAL/RilliyaVirtualAudioDriver.driver in a component package signed with the distributor's own Developer ID Installer identity.
  4. Notarize and staple the installer package before distribution.
  5. Explain that installation requires administrator authorization and a restart before Core Audio loads the plug-in.

The Developer ID Installer certificate is not tied to an application bundle ID. The driver bundle itself has a stable bundle identifier, and the package has a separate stable package identifier. Consumers never need Rilliya's signing certificates: a distributor signs its build with identities from its own Apple Developer account.

Rilliya's release scripts are a complete, inspectable example of Universal assembly, fixed-path packaging, signing, and notarization. They intentionally do not kill or restart Core Audio during installation.

Security boundary

Treat endpoint names and catalogs as untrusted persisted input. Construct them through VirtualAudioEndpointConfiguration and keep the built-in endpoint and catalog limits. Do not invoke private Core Audio APIs, write directly into the driver's storage, or bypass revision checks. A host should expose installation as an explicit user action rather than silently requesting administrator authorization.