xref: /expo/packages/@expo/cli/src/run/ios/appleDevice/protocol/LockdownProtocol.ts (revision 8a424beb)

/**
 * Copyright (c) 2021 Expo, Inc.
 * Copyright (c) 2018 Drifty Co.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

import plist from '@expo/plist';
import Debug from 'debug';
import { Socket } from 'net';

import type { ProtocolWriter } from './AbstractProtocol';
import { PlistProtocolReader, ProtocolClient, ProtocolReaderFactory } from './AbstractProtocol';
import { CommandError } from '../../../../utils/errors';

const debug = Debug('expo:apple-device:protocol:lockdown');
export const LOCKDOWN_HEADER_SIZE = 4;

export interface LockdownCommand {
  Command: string;
  [key: string]: any;
}

export interface LockdownResponse {
  Status: string;
  [key: string]: any;
}

export interface LockdownErrorResponse {
  Error: string;
  Request?: string;
  Service?: string;
}

export interface LockdownRequest {
  Request: string;
  [key: string]: any;
}

function isDefined(val: any) {
  return typeof val !== 'undefined';
}

export function isLockdownResponse(resp: any): resp is LockdownResponse {
  return isDefined(resp.Status);
}

export function isLockdownErrorResponse(resp: any): resp is LockdownErrorResponse {
  return isDefined(resp.Error);
}

export class LockdownProtocolClient<
  MessageType extends LockdownRequest | LockdownCommand = LockdownRequest,
> extends ProtocolClient<MessageType> {
  constructor(socket: Socket) {
    super(socket, new ProtocolReaderFactory(LockdownProtocolReader), new LockdownProtocolWriter());
  }
}

export class LockdownProtocolReader extends PlistProtocolReader {
  constructor(callback: (data: any) => any) {
    super(LOCKDOWN_HEADER_SIZE, callback);
  }

  parseHeader(data: Buffer) {
    return data.readUInt32BE(0);
  }

  parseBody(data: Buffer) {
    const resp = super.parseBody(data);
    debug(`Response: ${JSON.stringify(resp)}`);
    if (isLockdownErrorResponse(resp)) {
      if (resp.Error === 'DeviceLocked') {
        throw new CommandError('APPLE_DEVICE_LOCKED', 'Device is currently locked.');
      }

      if (resp.Error === 'InvalidService') {
        let errorMessage = `${resp.Error}: ${resp.Service} (request: ${resp.Request})`;
        if (resp.Service === 'com.apple.debugserver') {
          errorMessage +=
            '\nTry reconnecting your device. You can also debug service logs with `export DEBUG=expo:xdl:ios:*`';
        }
        throw new CommandError('APPLE_DEVICE_LOCKDOWN', errorMessage);
      }

      throw new CommandError('APPLE_DEVICE_LOCKDOWN', resp.Error);
    }
    return resp;
  }
}

export class LockdownProtocolWriter implements ProtocolWriter {
  write(socket: Socket, plistData: any) {
    debug(`socket write: ${JSON.stringify(plistData)}`);
    const plistMessage = plist.build(plistData);
    const header = Buffer.alloc(LOCKDOWN_HEADER_SIZE);
    header.writeUInt32BE(plistMessage.length, 0);
    socket.write(header);
    socket.write(plistMessage);
  }
}