appium-ios-remotexpc

A Node.js library for interacting with iOS devices through Appium using remote XPC services. This library enables communication with iOS devices through various services like system logs and network tunneling.

Overview

This library provides functionality for:

• Remote XPC (Cross Process Communication) with iOS devices
• Lockdown communication
• Device multiplexing via usbmuxd (lists USB and WiFi-attached devices; see below)
• Property list (plist) handling
• IPv6 tunneling services to iOS devices using TUN/TAP interfaces
• System log access

Installation

npm install appium-ios-remotexpc

Requirements

• Node.js 16 or later
• iOS device for testing
• Proper device pairing and trust setup
• Root/sudo privileges for tunnel creation (TUN/TAP interface requires elevated permissions)

Features

• Plist Handling: Encode, decode, parse, and create property lists for iOS device communication.
• Device communication over usbmux / usbmuxd: The system usbmuxd daemon exposes a single device list that includes machines plugged in over USB and, when pairing and wireless sync are set up, the same iPhone/iPad over WiFi. WiFi entries are marked ConnectionType: Network (USB entries use ConnectionType: USB). This library connects through usbmuxd the same way for both; the tunnel path is unchanged (lockdown → CoreDeviceProxy → TUN/TAP → Remote XPC).
• Remote XPC: Establish Remote XPC connections with iOS devices.
• Service Architecture: Connect to various iOS services:
  • System Log Service: Access device logs
  • Tunnel Service: Network tunneling to/from iOS devices
  • Diagnostic Service: Device diagnostics
  • AFC Service: File system operations on iOS devices
• Pair Record Management: Read and write device pairing records.
• Packet Streaming: Stream packets between host and device for service communication.

Configuration

Environment Variables

APPIUM_IOS_REMOTEXPC_LOG_LEVEL

Controls the logging verbosity of the library.

• Default: info
• Possible values: Standard log levels supported by @appium/support logger
• silly - Most verbose, logs everything
• verbose - Very detailed logs
• debug - Detailed debugging information
• info - General informational messages (default)
• warn - Warning messages
• error - Error messages only
• Usage:

# Set log level to debug for verbose output
APPIUM_IOS_REMOTEXPC_LOG_LEVEL=debug npm test

# Set log level to error for minimal output
APPIUM_IOS_REMOTEXPC_LOG_LEVEL=error node your-script.js

This is particularly useful for debugging issues or reducing log noise in production environments.

Architecture Flow

The following diagram illustrates the high-level flow of how the tunnel is created:

Role of TUN/TAP

The appium-ios-tuntap (previously tuntap-bridge) module plays a crucial role in establishing network connectivity:

1. TLS Socket Input: Receives the secure TLS socket connection from CoreDeviceProxy
2. Virtual Network Interface: Creates a TUN/TAP virtual network interface on the host system
3. IPv6 Tunnel: Establishes an IPv6 tunnel between the host and iOS device
4. Packet Routing: Routes network packets between the virtual interface and the iOS device
5. Service Access: Enables access to iOS shim services through the tunnel

Technical Details: - Platform Support: Works on both macOS and Linux - IPv6 Support: Creates IPv6 tunnels for modern iOS communication - Packet Handling: Manages packet routing between virtual interface and device - Automatic Cleanup: Properly closes tunnels and cleans up interfaces

Security Considerations: - Requires root/sudo access for TUN/TAP interface creation - Uses TLS for secure communication with iOS devices

Usage

Creating a Tunnel (Low-level approach)

import {
  createLockdownServiceByUDID,
  rsdSessionLockKey,
  startCoreDeviceProxyTcp,
  TunnelManager,
} from 'appium-ios-remotexpc';

// Create lockdown service
const { lockdownService, device } = await createLockdownServiceByUDID(udid);

// Start CoreDeviceProxy (raw TCP; TLS handled in native forwarder)
const { socket, cert, key } = await startCoreDeviceProxyTcp(
  lockdownService,
  device.DeviceID,
  device.Properties.SerialNumber,
);

// Create tunnel using tuntap
const tunnel = await TunnelManager.getTunnel(socket, { cert, key });
console.log(`Tunnel created at ${tunnel.Address} with RSD port ${tunnel.RsdPort}`);

// Discover RSD services (serialized per tunnel; closed before return)
await TunnelManager.runSerializedRsdSession(
  rsdSessionLockKey(tunnel.Address, tunnel.RsdPort),
  async () => {
    const remoteXPC = await TunnelManager.connectRemoteXPCUnlocked(
      tunnel.Address,
      tunnel.RsdPort,
    );
    try {
      console.log(remoteXPC.getServices());
    } finally {
      await remoteXPC.close();
    }
  },
);

iPhone / iPad over WiFi (usbmuxd “network” devices)

usbmuxd (the multiplexer daemon, e.g. on macOS) does not only list USB devices: once a device is paired with the host and wireless sync / lockdown-over-WiFi is enabled, the same daemon’s device list includes that device as attached over WiFi. In plist responses from ListDevices, those rows carry ConnectionType: Network (and a distinct DeviceID from any USB listing for the same physical device).

There is no separate “WiFi API” in this library: call createUsbmux() → listDevices() (or any other client that queries usbmuxd) and use the returned DeviceID and UDID with createLockdownServiceByUDID and the tunnel steps in the previous section—identical to USB.

Typical host-side setup:

1. Pair the device with this Mac and tap Trust on the device if prompted.
2. Allow the device to connect over WiFi (e.g. in Finder under the device, enable Show this [device] when on WiFi, or use Xcode Devices and Simulators with the equivalent option so lockdown can reach the device without USB).
3. Confirm usbmuxd reports the device with ConnectionType: Network—for example by logging the result of listDevices() from this library, or by checking another usbmuxd client’s device list while the device is on the same network and not on USB.

For an end-to-end tunnel smoke test with the tunnel registry HTTP API, use npm run tunnel-creation or npm run test:tunnel-creation (see scripts/test-tunnel-creation.ts), usually with sudo for TUN/TAP.

Apple TV / tvOS over WiFi

Apple TV and tvOS devices over WiFi are supported. The following symbols are part of the public API and are intended for external use (e.g. by the Appium XCUITest driver):

import {
  AppleTVPairingService,
  UserInputService,
  AppleTVTunnelService,
} from 'appium-ios-remotexpc';

const userInput = new UserInputService();
const pairing = new AppleTVPairingService(userInput);
const result = await pairing.discoverAndPair('Living Room');

For step-by-step pairing instructions, see the Apple TV Pairing Instructions.

Development

Setup

# Clone the repository
git clone https://github.com/yourusername/appium-ios-remotexpc.git
cd appium-ios-remotexpc

# Install dependencies
npm install

# Build the project
npm run build

Continuous Integration

This project uses GitHub Actions for continuous integration and Dependabot for dependency management:

• Lint and Build: Automatically runs linting and builds the project on Node.js LTS.
• Format Check: Ensures code formatting adheres to project standards
• Test Validation: Validates that test files compile correctly (actual tests require physical devices)
• Dependabot: Automatically creates PRs for dependency updates weekly

All pull requests must pass these checks before merging. The workflows are defined in the .github/workflows directory.

Scripts

• npm run build - Clean and build the project
• npm run lint - Run ESLint
• npm run format - Run prettier
• npm run lint:fix - Run ESLint with auto-fix
• npm test - Run tests (requires sudo privileges for tunneling)

CLI helpers under scripts/ are ESM (.mjs) and load the library via the package entrypoint. Run npm run build before using them so appium-ios-remotexpc resolves to build/.

• npm run tunnel-creation / npm run test:tunnel-creation — Create USB tunnels and start the tunnel registry HTTP API (requires sudo)
• npm run test:tunnel-creation:lsof — Same as above with --keep-open (for inspecting open sockets)
• npm run pair-appletv — Pair an Apple TV over WiFi for Remote XPC (requires sudo)
• npm run start-appletv-tunnel — Start an Apple TV WiFi tunnel and tunnel registry (requires sudo)

Pass --help after -- to any of these npm scripts to see CLI flags (for example: npm run pair-appletv -- --help).

Project Structure

• /scripts - Optional CLI helpers (ESM .mjs) for tunnels and Apple TV pairing; use via npm run entries under Scripts
• /src - Source code
• /lib - Core libraries
  • /lockdown - Device lockdown protocol
  • /pair-record - Pairing record handling
  • /plist - Property list processing
  • /remote-xpc - XPC connection handling
  • /tunnel - Tunneling implementation with tuntap integration
  • /usbmux - usbmuxd client (USB and WiFi-listed devices)
• /services - Service implementations
  • /ios
  • /diagnostic-service - Device diagnostics
  • /syslog-service - System log access
  • /tunnel-service - Network tunneling

Testing

# Run all tests
npm test

Note: Integration tests require: - Physical iOS devices connected (USB and/or WiFi if the device is paired and visible to usbmux as Network) - Sudo privileges for tunnel creation - Device trust established

License

Apache-2.0

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Notes

This project is under active development. APIs may change without notice.