昨花了点时间,参考github issues 总算实现了基于xposed的系统服务注入,本文目的是为了“解决应用之间hook后数据共享,任意app ServiceManager.getService就
可以直接调用aidl实现了进程通信”(比如aidl service实现socket,http server等,或者从某app获取数据传递给另外个app等场景,能做什么大家自己想吧,当然也可以实现非xposed版本的,需要通过直接smali方式。因为需快速实现,我就基于xposed的方案凑活用着用吧)
Xposed我就不介绍了,Xposed有2个重要接口,一个是针对应用级别hook:IXposedHookLoadPackage,另一个就是针对系统级别的:IXposedHookZygoteInit
这里将使用IXposedHookZygoteInit实现aidl添加到系统服务中,当然,通过IXposedHookLoadPackage也是可以实现的,但是因为我们注入的服务是希望像系统服务一样,开机启动,关机停止,另外IXposedHookZygoteInit本身就是定位在针对系统hook,所以还是建议使用IXposedHookZygoteInit。
直接进入正题:
1.创建 android.os.ICustomService.aidl
package android.os; // Declare any non-default types here with import statements interface ICustomService { String sayHello(); }
2.创建CustomService实现类
1 public class CustomService extends ICustomService.Stub { 2 private Context mContext; 3 public CustomService(Context context) { 4 mContext = context; 5 } 6 7 @Override 8 public String sayHello() throws RemoteException { 9 return "Just Hello World"; 10 } 11 12 //ActivityManagerService的systemReady在所有服务初始化完成后触发,这定义这个是为了实现自定义服务的初始化代码实现 13 public void systemReady() { 14 // Make your initialization here 15 } 16 }
3.创建ApplicationSocket,实现IXposedHookZygoteInit接口,这实现系统启动时候触发hook
1 public class ApplicationSocket implements IXposedHookZygoteInit{ 2 public static String TAG = "ApplicationSocket"; 3 @Override 4 public void initZygote(StartupParam startupParam) throws Throwable { 5 XposedBridge.hookAllMethods(ActivityThread.class, "systemMain", new SystemServiceHook()); 6 } 7 }
4.创建SystemServiceHook 重写XC_MethodHook,实现注册服务,这也是最核心的类
1 import android.content.Context; 2 import android.os.Build; 3 import android.os.CustomService; 4 import android.os.ICustomService; 5 import android.os.ServiceManager; 6 7 import de.robv.android.xposed.XC_MethodHook; 8 import de.robv.android.xposed.XposedBridge; 9 import de.robv.android.xposed.XposedHelpers; 10 11 /** 12 * Created by bluce on 17/12/5. 13 */ 14 15 public class SystemServiceHook extends XC_MethodHook { 16 private static CustomService oInstance; 17 private static boolean systemHooked; 18 19 @Override 20 protected void afterHookedMethod(MethodHookParam param) throws Throwable { 21 if (systemHooked) { 22 return; 23 } 24 final ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); 25 Class activityManagerServiceClazz = null; 26 try { 27 activityManagerServiceClazz = XposedHelpers.findClass("com.android.server.am.ActivityManagerService", classLoader); 28 } catch (RuntimeException e) { 29 // do nothing 30 } 31 if (!systemHooked && activityManagerServiceClazz!=null) { 32 systemHooked = true; 33 //系统服务启动完毕,通知自定义服务 34 XposedBridge.hookAllMethods( 35 activityManagerServiceClazz, 36 "systemReady", 37 new XC_MethodHook() { 38 @Override 39 protected final void afterHookedMethod(final MethodHookParam param) { 40 oInstance.systemReady(); 41 XposedBridge.log(">>>systemReady!!!!"); 42 } 43 } 44 ); 45 //注册自定义服务到系统服务中 46 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { 47 XposedBridge.hookAllConstructors(activityManagerServiceClazz, new XC_MethodHook() { 48 @Override 49 protected void afterHookedMethod(MethodHookParam param) throws Throwable { 50 Context context = (Context) XposedHelpers.getObjectField(param.thisObject, "mContext"); 51 registerService(classLoader,context); 52 } 53 }); 54 }else{ 55 XposedBridge.hookAllMethods( 56 activityManagerServiceClazz, 57 "main", 58 new XC_MethodHook() { 59 @Override 60 protected final void afterHookedMethod(final MethodHookParam param) { 61 Context context = (Context) param.getResult(); 62 registerService(classLoader,context); 63 } 64 } 65 ); 66 } 67 } 68 } 69 70 private static void registerService(final ClassLoader classLoader, Context context) { 71 XposedBridge.log(">>>register service, Build.VERSION.SDK_INT"+Build.VERSION.SDK_INT); 72 oInstance = new CustomService(context); 73 Class<?> ServiceManager = XposedHelpers.findClass("android.os.ServiceManager",classLoader); 74 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { 75 //避免java.lang.SecurityException错误,从5.0开始,selinux服务名称需要加前缀"user." 76 XposedHelpers.callStaticMethod( 77 ServiceManager, 78 "addService", 79 "user.custom.service", 80 oInstance, 81 true 82 ); 83 } else { 84 XposedHelpers.callStaticMethod( 85 ServiceManager, 86 "addService", 87 "custom.service", 88 oInstance 89 ); 90 } 91 } 92 93 94 //use service demo 95 public static ICustomService mService; 96 public static String someMethod(Context context) { 97 try { 98 if (mService == null) { 99 mService=ICustomService.Stub.asInterface(ServiceManager.getService("user.wx_custom.service")); 100 //mService =(ICustomService)context.getSystemService("wx_custom.service"); 101 } 102 return mService.sayHello(); 103 } catch (Exception e) { 104 System.out.println(e.getMessage()); 105 e.printStackTrace(); 106 } 107 return ">>> someMethod failed!!! "; 108 } 109 }
5.在当前应用activity中调用系统服务,service实现可以创建成单独的module,这样就实现不同项目直接使用,最重要的是在当前项目xposed hook代码中可以直接使用了,这也是本文的最初衷。
button = (Button) findViewById(R.id.testButton); button.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ if(true){ //testPattern();return; //HookTest.registerReceiver(context); String str = SystemServiceHook.someMethod(MainActivity.context); if(str!=null){ System.out.println(">>>>:::"+str); } return; } } } ;
基于以上,CustomService整体的代码就实现了,重启系统就变成了系统服务,可以直接使用。但是以下2点需要特别注意:
1.com.android.server.am.ActivityManagerService是framework不公开的方法和类,所以项目需要导入AndroidHiddenAPI.jar这个包
2.android5.0之前SystemContext通过call ActivityManagerService的main方法就可以直接获取,但是5.0开始是通过createSystemContext方法生产,所以只能判断下版本,然后一个通过构造取获取,一个通过main返回结果获取