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Xposed框架Hook相关api的使用
首先创建测试类继承IXposedHookLoadPackage, 以下所有的hook方法都在handleLoadPackage方法内部进行调用
public class HookTest implements IXposedHookLoadPackage {
@Override
public void handleLoadPackage(XC_LoadPackage.LoadPackageParam lpparam) throws Throwable {
XposedBridge.log("HOOK初体验：" + lpparam.processName + ":" + lpparam.packageName);
}
准备需要被hook的代码用于测试
public class HookDemo {
private String Tag = "HookDemo";
private static int staticInt = 100;
public int publicInt = 200;
private int privateInt = 300;
public HookDemo(){
this("NOHook");
Log.d(Tag, "HookDemo() was called|||");
}
private HookDemo(String str){
Log.d(Tag, "HookDemo(String str) was called|||" + str);
}
public void hookDemoTest(){
Log.d(Tag, "staticInt = " + staticInt);
Log.d(Tag, "PublicInt = " + publicInt);
Log.d(Tag, "privateInt = " + privateInt);
publicFunc("NOHook");
Log.d(Tag, "PublicInt = " + publicInt);
Log.d(Tag, "privateInt = " + privateInt);
privateFunc("NOHook");
staticPrivateFunc("NOHook");
String[][] str = new String[1][2];
Map map = new HashMap<String, String>();
map.put("key", "value");
ArrayList arrayList = new ArrayList();
arrayList.add("listValue");
complexParameterFunc("NOHook", str, map, arrayList);
repleaceFunc();
anonymousInner(new Animal() {
@Override
public void eatFunc(String value) {
Log.d(Tag, "eatFunc(String value) was called|||" + value);
Log.d(Tag, "anonymoutInt = " + anonymoutInt);
}
}, "NOHook");
InnerClass innerClass = new InnerClass();
innerClass.InnerFunc("NOHook");
}
public void publicFunc(String value){
Log.d(Tag, "publicFunc(String value) was called|||" + value);
}
private void privateFunc(String value){
Log.d(Tag, "privateFunc(String value) was called|||" + value);
}
static private void staticPrivateFunc(String value){
Log.d("HookDemo", "staticPrivateFunc(Strin value) was called|||" + value);
}
private void complexParameterFunc(String value, String[][] str, Map<String,String> map, ArrayList arrayList)
{
Log.d("HookDemo", "complexParameter(Strin value) was called|||" + value);
}
private void repleaceFunc(){
Log.d(Tag, "repleaceFunc will be replace|||");
}
public void anonymousInner(Animal dog, String value){
Log.d(Tag, "anonymousInner was called|||" + value);
dog.eatFunc("NOHook");
}
private void hideFunc(String value){
Log.d(Tag, "hideFunc was called|||" + value);
}
private void argFunc(Objcet... value){
Log.d(Tag, "argFunc was called|||" + value);
}
class InnerClass{
public int innerPublicInt = 10;
private int innerPrivateInt = 20;
public InnerClass(){
Log.d(Tag, "InnerClass constructed func was called");
}
public void InnerFunc(String value){
Log.d(Tag, "InnerFunc(String value) was called|||" + value);
Log.d(Tag, "innerPublicInt = " + innerPublicInt);
Log.d(Tag, "innerPrivateInt = " + innerPrivateInt);
}
}
}
- 修改类中的私有静态变量
Class<?> clazz = XposedHelpers.findClass("com.example.xposedhooktarget.HookDemo", lpparam.classLoader);
XposedHelpers.setStaticIntField(clazz, "staticInt", 99);
- Hook无参构造函数
Class<?> clazz = XposedHelpers.findClass("com.example.xposedhooktarget.HookDemo", loadPackageParam.classLoader);
XposedHelpers.findAndHookConstructor(clazz, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
XposedBridge.log("Haha, HookDemo constructed was hooked");
//大坑，此时对象还没有建立，即不能获取对象，也不能修改非静态变量的值
//XposedHelpers.setIntField(param.thisObject, "publicInt", 199);
//XposedHelpers.setIntField(param.thisObject, "privateInt", 299);
}
});
- Hook有参构造函数，并修改参数
XposedHelpers.findAndHookConstructor(clazz, String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, HookDemo(str) are hooked";
}
});
- Hook公有方法publicFunc，并修改参数以及修改下publicInt和privateInt的值,再顺便调用一下隐藏函数hideFunc
XposedHelpers.findAndHookMethod(clazz, "publicFunc", String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, publicFunc are hooked";
//修改成员变量的值
XposedHelpers.setIntField(param.thisObject, "publicInt", 199);
XposedHelpers.setIntField(param.thisObject, "privateInt", 299);
//调用函数
XposedHelpers.callMethod(param.thisObject, "hideFunc", "Haha, hideFunc was hooked");
}
});
- Hook私有方法privateFunc，并修改参数
XposedHelpers.findAndHookMethod(clazz, "privateFunc", String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, privateFunc are hooked";
}
});
- Hook私有静态方法staticPrivateFunc, 并修改参数
XposedHelpers.findAndHookMethod(clazz, "staticPrivateFunc", String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, staticPrivateFunc are hooked";
}
});
- Hook复杂参数函数complexParameterFunc
Class fclass1 = XposedHelpers.findClass("java.util.Map", loadPackageParam.classLoader);
Class fclass2 = XposedHelpers.findClass("java.util.ArrayList", loadPackageParam.classLoader);
XposedHelpers.findAndHookMethod(clazz, "complexParameterFunc", String.class,
"[[Ljava.lang.String;", fclass1, fclass2, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, complexParameterFunc are hooked";
}
});
- Hook私有方法repleaceFunc, 并替换打印内容
XposedHelpers.findAndHookMethod(clazz, "repleaceFunc", new XC_MethodReplacement() {
@Override
protected Object replaceHookedMethod(MethodHookParam methodHookParam) throws Throwable {
Log.d("HookDemo", "Haha, repleaceFunc are replaced");
return null;
}
});
- Hook方法, anonymousInner， 参数是抽象类，先加载所需要的类即可
Class animalClazz = loadPackageParam.classLoader.loadClass("com.example.xposedhooktarget.Animal");
XposedHelpers.findAndHookMethod(clazz, "anonymousInner", animalClazz, String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
XposedBridge.log("HookDemo This is test");
param.args[1] = "Haha, anonymousInner are hooked";
}
});
- Hook匿名类的eatFunc方法，修改参数，顺便修改类中的anonymoutInt变量
XposedHelpers.findAndHookMethod("com.example.xposedhooktarget.HookDemo$1", clazz.getClassLoader(),
"eatFunc", String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, eatFunc are hooked";
XposedHelpers.setIntField(param.thisObject, "anonymoutInt", 499);
}
});
- Hook内部类InnerClass的InnerFunc方法，修改参数，顺便修改类中的innerPublicInt和innerPrivateInt变量
final Class<?> clazz1 = XposedHelpers.findClass("com.example.xposedhooktarget.HookDemo$InnerClass", loadPackageParam.classLoader);
XposedHelpers.findAndHookMethod(clazz1, "InnerFunc", String.class, new XC_MethodHook() {
@Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
param.args[0] = "Haha, InnerFunc was hooked";
XposedHelpers.setIntField(param.thisObject, "innerPublicInt", 9);
XposedHelpers.setIntField(param.thisObject, "innerPrivateInt", 19);
}
});
- 对于一些延迟动态加载的代码,hook方式
XposedHelpers.findAndHookMethod("dalvik.system.DexFile", lpparam.classLoader, "loadClass",
String.class, "java.lang.ClassLoader", new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
String className = (String) param.args[0];
Object result = param.getResult();
if (result != null && result instanceof Class) {
if ("com.alipay.mobile.nebulauc.impl.UCWebViewClient".equals(className)) {
// hookLoadWebViewClient(((Class) result).getClassLoader());
}
}
}
});
- Hook有可变参数的方法
XposedHelpers.findAndHookMethod(clazz, "argFunc", Object[].class,new XC_MethodHook() {
@Override
protected Object afterHookedMethod(MethodHookParam methodHookParam) throws Throwable {
}
});
总结
-
无论hook公有私有方法还是静态方法 ,抑或可变参方法,甚至是带返回值的方法,统一使用
findAndHookMethod这个Api -
xposed无法hook接口和抽象类方法
-
Hook逻辑类可实现的接口有 :
-
安卓系统启动的时候（使用 IXposedHookZygoteInit 接口）、
-
一个新的app被加载的时候（使用 IXposedHookLoadPackage 接口）、
-
一个资源被初始化的时候（ 使用 IXposedHookInitPackageResources 接口 )
-
-
实现IXposedHookLoadPackage 并使用 XposedBridge.log 打印的日志,当启动第三方应用后,Android Studio控制台无法查看到日志信息,需要在xposed应用内进行查看
-
参数为基本数据类型时需要传对应包装类的type属性,比如int传Integer.TYPE, 否则提示找不到方法,如果参数为引用数据类型,那直接传xxx.class即可
-
-
beforeHookedMethod 会在调用原方法前执行，如果使用setResult则跳过原方法，并返回setResult参数中的值。
-
afterHookedMethod 会在调用原方法后执行，setResult可改变返回值
-
replaceHookedMethod 会完全替换原方法，即原方法不执行，且返回值可以直接return，setResult不生效。
-
注:每次修改完毕后需要重启才生效
附
Hook 修改方法返回值
XposedHelpers.findAndHookMethod(clazz, method, new Object[]{new XC_MethodHook() {
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
param.setResult(result); // 设置返回值
}
}});
Hook 获取方法返回值
XposedHelpers.findAndHookMethod(clazz, method, new Object[]{new XC_MethodHook() {
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
Object result = param.getResult(); //获取返回值
}
}});
Hook 获取方法传入的参数值
XposedHelpers.findAndHookMethod(claName, cl, "i", String.class, String.class, Object[].class, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
// 数组param.args存储的参数列表里的值
XposedBridge.log(TAG + param.args[0]);
XposedBridge.log(TAG + param.args[1]);
XposedBridge.log(TAG + param.args[2]);
}
});
Hook 给方法传值
Class cla = XposedHelpers.findClass(className, loadPackageParam.classLoader);
Object com = XposedHelpers.callStaticMethod(cla, "getInstance");
XposedHelpers.callMethod(com, "setDebug", true); // 传入指定值
Hook 获取Intent的值
private void hookGetIntent(XC_LoadPackage.LoadPackageParam loadPackageParam) {
try {
XposedHelpers.findAndHookMethod("android.app.Activity", loadPackageParam.classLoader, "getIntent", new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
Intent sou = (Intent) param.getResult();
KLog.d("hookGetIntent:" + sou.toURI().toString());
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
Hook 广播发送的Intent信息
private void hookSendBroadcast(XC_LoadPackage.LoadPackageParam loadPackageParam) {
try {
XposedHelpers.findAndHookMethod("android.content.ContextWrapper", loadPackageParam.classLoader, "sendBroadcast", Intent.class, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
Intent sou = (Intent) param.args[0];
KLog.d("sendBroadcast:" + sou.toURI().toString());
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
Xposed一般Hook的是默认的dex文件，但是现在很多的APP都有多个Dex文件，所以使用Xposed时，经常遇到类名路径正确却出现ClassNotFoundError找不到类的错误。要解决这个问题，需要获取对应Dex文件的上下文环境。
Android在加载dex文件后会创建一个Application类，然后会调用attach方法，attach方法的参数就是上下文context，而且attach方法是final方法，不会因为被覆盖而hook不到，拿到这个context就可以获取对应的classload，然后就可以顺利hook到multidex的类了。
XposedHelpers.findAndHookMethod(Application.class, "attach", Context.class, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
ClassLoader cl = ((Context) param.args[0]).getClassLoader(); // 获取ClassLoader
Class<?> hookClass = null;
try {
hookClass = cl.loadClass(claName); // 获取Class
// 使用cl 和 hookClass 完成hook
XposedHelpers.setStaticIntField(hookClass, fieldName, val);
XposedHelpers.findAndHookMethod(claName, cl, "i", String.class, String.class, Object[].class, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
XposedBridge.log(TAG + param.args[0]);
XposedBridge.log(TAG + param.args[1]);
XposedBridge.log(TAG + param.args[2]);
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
});
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