Log all methods called in an app by Xposed - xposed

Question

As title said, I want to use xposed to log all methods called in an app from it start till I stop it. I only want to log Class name, Method name, don't want to hook all method.
I try this code, but get error getMethod not found.
findAndHookMethod("java.lang.Class", lpparam.classLoader, "getMethod", String.class, Object.class, new XC_MethodHook()
Thanks in advance!

Answer 1

There is no one line solution like what you seem to be searching.
Hooking all methods will let log what methods were called by app from it start till stop (sort of - see below), but if (for some reason) you don't want to hook all methods, the only solution I can think of is modifying the java VM itself (NOT something I would recommend.)
A solution that (sort of) works
What I did was first use apktool to decompile my apk and get the names of all the methods in all the classes.
Then I used xposed to hook into every single method of every class and print to the dlog the current function name.
Why it only sort of works
Xposed has an overhead whenever it hook a methods. For general usage of xposed apps, it isnt much. But when you start hooking each and every methods of an app, the overhead very quickly becomes ridiculously large - So much so that while the above methods works for small apps, for any large app it very quickly causes the app to hang and then crash.
An alternative that also sort-of works
FRIDA is a way to inject javascript to native apps. Here they show you how to log all function calls. While in the above link they log all function calls in a piece of python code, the same code also works for Android.

Answer 2

There is a way to log all Java methods.Modify XposedBridge.
Xposed hook java method through XposedBridge.java's method
"handleHookedMethod(Member method, int originalMethodId, Object additionalInfoObj, thisObject, Object[] args)"
Log.v(TAG, "className " + method.getClass().getName() + ",methodName " + method.getName());

Answer 3

As mentioned before Xposed is not the way to go in this situation due to its overhead.
The simplest solution is just to use dmtracedump as provided by Google. Most x86 Android images and emulator come with the debuggable flag on (ro.debuggable) so you can even use it for closed source apps.
Additionally other tools such as Emma are known to work with Android as well, but these might need modifications to the source code.

Answer 4

I found a solution.
See this code snippet below.
package com.kyunggi.logcalls;
import android.content.pm.*;
import android.util.*;
import dalvik.system.*;
import de.robv.android.xposed.*;
import de.robv.android.xposed.callbacks.XC_LoadPackage.*;
import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import static de.robv.android.xposed.XposedHelpers.findAndHookMethod;
import android.app.*;
public class Main implements IXposedHookLoadPackage {
private String TAG = "LogCall";
public void handleLoadPackage(final LoadPackageParam lpparam) throws Throwable {
if (!lpparam.packageName.equals("com.android.bluetooth")) {
Log.i(TAG, "Not: " + lpparam.packageName);
return;
}
Log.i(TAG, "Yes " + lpparam.packageName);
//Modified https://d3adend.org/blog/?p=589
ApplicationInfo applicationInfo = AndroidAppHelper.currentApplicationInfo();
if (applicationInfo.processName.equals("com.android.bluetooth")) {
Set<String> classes = new HashSet<>();
DexFile dex;
try {
dex = new DexFile(applicationInfo.sourceDir);
Enumeration entries = dex.entries();
while (entries.hasMoreElements()) {
String entry = (String) entries.nextElement();
classes.add(entry);
}
dex.close();
} catch (IOException e) {
Log.e("HookDetection", e.toString());
}
for (String className : classes) {
boolean obex = false;
if (className.startsWith("com.android.bluetooth") || (obex = className.startsWith("javax.obex"))) {
try {
final Class clazz = lpparam.classLoader.loadClass(className);
for (final Method method : clazz.getDeclaredMethods()) {
if (obex) {
if (!Modifier.isPublic(method.getModifiers())) {
continue; //on javax.obex package, hook only public APIs
}
}
XposedBridge.hookMethod(method, new XC_MethodHook() {
final String methodNam = method.getName();
final String classNam = clazz.getName();
final StringBuilder sb = new StringBuilder("[");
final String logstr = "className " + classNam + ",methodName " + methodNam;
#Override
protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
//Method method=(Method)param.args[0];
sb.setLength(0);
sb.append(logstr);
//Log.v(TAG,logstr);
for (Object o : param.args) {
String typnam = "";
String value = "null";
if (o != null) {
typnam = o.getClass().getName();
value = o.toString();
}
sb.append(typnam).append(" ").append(value).append(", ");
}
sb.append("]");
Log.v(TAG, sb.toString());
}
});
}
} catch (ClassNotFoundException e) {
Log.wtf("HookDetection", e.toString());
}
}
}
}
// ClassLoader rootcl=lpparam.classLoader.getSystemClassLoader();
//findAndHookMethod("de.robv.android.xposed.XposedBridge", rootcl, "handleHookedMethod", Member.class, int.class, Object.class, Object.class, Object[].class, );
}
}