SandHook

Android ART Hook

Version

Chinese

中文文档以及实现

中文 Blog

arch support

• ARM64
• ARM32(no tested)
• Thumb-2

OS

4.4(ART Runtime) - 10.0

Scope

• Object Methods
• Static Methods
• Constructors
• System Methods
• JNI Methods

hook abstract method is not recommended, you can invoke its impl method.

cant hook if lined

how to use

implementation 'com.swift.sandhook:hooklib:3.1.0'

Annotation API

• hook method must be a static method
• first par must be this if method is not static
• method description must "same"(can be isAssignableFrom) with origin method
• backup method same with above

@HookClass(Activity.class)
//@HookReflectClass("android.app.Activity")
public class ActivityHooker {

    @HookMethodBackup("onCreate")
    @MethodParams(Bundle.class)
    static Method onCreateBackup;

    @HookMethodBackup("onPause")
    static HookWrapper.HookEntity onPauseBackup;

    @HookMethod("onCreate")
    @MethodParams(Bundle.class)
    public static void onCreate(Activity thiz, Bundle bundle) throws Throwable {
        Log.e("ActivityHooker", "hooked onCreate success " + thiz);
        SandHook.callOriginByBackup(onCreateBackup, thiz, bundle);
    }

    @HookMethod("onPause")
    public static void onPause(@ThisObject Activity thiz) throws Throwable {
        Log.e("ActivityHooker", "hooked onPause success " + thiz);
        onPauseBackup.callOrigin(thiz);
    }

}



//or like this:

@HookClass(TestClass.class)
public class NewAnnotationApiHooker {

    @HookMethod("testNewHookApi")
    public static void onTestNewHookApi(@ThisObject TestClass thiz, @Param("com.swift.sandhook.MainActivity") Activity activity, int a) {
        Log.e("TestClassHook", "testNewHookApi been hooked");
        onTestNewHookApiBackup(thiz, activity, a);
    }

    @HookMethodBackup("testNewHookApi")
    public static void onTestNewHookApiBackup(@ThisObject TestClass thiz, @Param("com.swift.sandhook.MainActivity") Activity activity, int a) {
        onTestNewHookApiBackup(thiz, activity, a);
    }

}



//first set debuggable
SandHookConfig.DEBUG = BuildConfig.DEBUG;

and

//add hookers
SandHook.addHookClass(CtrHook.class, LogHooker.class, CustmizeHooker.class, ActivityHooker.class, ObjectHooker.class);

you can also use:
SanHook.public static boolean hook(Member target, Method hook, Method backup) {}

if hookers is in plugin(like xposed):

provided 'com.swift.sandhook:hookannotation:3.1.0'

in your plugin

if OS <= 5.1 backup method can call itself to avoid be inlining

Xposed API

Now you can use Xposed api:

implementation 'com.swift.sandhook:xposedcompat:3.1.0'

//setup for xposed
XposedCompat.cacheDir = getCacheDir();
XposedCompat.context = this;
XposedCompat.classLoader = getClassLoader();
XposedCompat.isFirstApplication= true;  
//do hook
XposedHelpers.findAndHookMethod(Activity.class, "onResume", new XC_MethodHook() {
      @Override
      protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
          super.beforeHookedMethod(param);
          Log.e("XposedCompat", "beforeHookedMethod: " + param.method.getName());
      }

      @Override
      protected void afterHookedMethod(MethodHookParam param) throws Throwable {
          super.afterHookedMethod(param);
          Log.e("XposedCompat", "afterHookedMethod: " + param.method.getName());
      }
});

Notice

Call Origin

!!!!!!!!

when OS >= 8.0 you must call backup method in hook method, if you want call it in other method, please call SandHook.compileMethod(otherMethod) before call backup method.

because when ART trigger JIT from profiling, JIT will invoke -> ResolveCompilingMethodsClass -> ClassLinker::ResolveMethod -> CheckIncompatibleClassChange -> ThrowIncompatibleClassChangeError finally!!!

Inline

disable JIT inline

We can do nothing to prevent some methods been inlined before app start, but we can try to disable VM Jit Inline after launch.

if you will hook some method that could be inlined, please call SandHook.disableVMInline()(OS >= 7.0) in Application.OnCreate()

Deoptimize

You can also deoptimize a caller that inlined your hook method by SandHook.deCompile(caller), just implement >= 7.0

Hidden API

SandHook.passApiCheck();

To bypass hidden api on P & Q

Demo

SandVXPosed

non-Root Xposed Environment Demo (VirtualApp with SandHook):

https://github.com/ganyao114/SandVXposed

EdXposed(SandHook Brunch)

Unofficial xposed framework >= 8.0

See release above

https://github.com/ElderDrivers/EdXposed/tree/sandhook

Android Q(10.0)

in MyApp.java

//if you want test Android Q, please set true, because SDK_INT of Android Q is still 28 public final static boolean testAndroidQ = false;

References

• Epic:https://github.com/tiann/epic
• Yahfa:https://github.com/rk700/YAHFA