Database Develop

[Q] problem with class static value

have some problems with static values used as flags.
for example I need to hook 2 methods in different FRAMEWORK classes during initZygote. (no problem with system apps during handleLoadPackage)
I hook method in first class, set static value and waiting when another method of another class will be triggered.
once another method is invoked, flag always has it's initial state.
it looks like each hook method processed in different class instances.
i tried volatile type, tried to synchronize - nothing help.
unreliable remedy:
1. register broadcast receiver inside hook method.
2. send action to own service
3. send broadcast from own service.
4. catch broadcast with receiver.
BUT it is not battery cost efficient solution in my case. And mostly I receive broadcast message when hooking method already processed and returned value. Otherwise I need to wait when service will process request and send broadcast. But it is not usable.
is there any solution?
Code:
public class XMain implements IXposedHookInitPackageResources, IXposedHookZygoteInit, IXposedHookLoadPackage
{
private static boolean isNeedToRun = false;
public void initZygote(StartupParam startupParam) throws Throwable
{
findAndHookMethod("com.class1", null, "method1", int.class, new XC_MethodHook()
{
@Override
protected void beforeHookedMethod(final MethodHookParam param) throws Throwable
{
isNeedToRun = true;
}
});
findAndHookMethod("com.class2", null, "method2", int.class, new XC_MethodHook()
{
@Override
protected void beforeHookedMethod(final MethodHookParam param) throws Throwable
{
if (isNeedToRun) param.setResult(null); // always FALSE even if previous hook set as TRUE
}
});
}
}

Why do you think that using a broadcast receiver is not battery efficient?

GermainZ said:
Why do you think that using a broadcast receiver is not battery efficient?
Click to expand...
Click to collapse
I do not want to invoke service and send broadcast very often (several thousands times during normal battery one cycle charge)
I just want use easiest way by storing flag inside class and worried that users will find the module in the list of gluttonous applications.

Falseclock said:
Code:
if (isNeedToRun) param.setResult(null); // always FALSE even if previous hook set as TRUE
Click to expand...
Click to collapse
You're probably not considering the fact that different processes will each have its own "isNeededToRun" variable.
Whenever new processes (system_process, apps, etc.) are forked from zygote, each of them will have its own independent state which includes this static variable. From then on they will be completely separate things even if it's a variable with the same name, don't get confused by that.
Try adding a Log.i(...) call to write something in both methods, and then check the logcat for the pid in which the messages are logged. I bet you'll see that different pids are writing and reading, and you can't expect them to be doing it in the same global variable.

Tungstwenty said:
You're probably not considering the fact that different processes will each have its own "isNeededToRun" variable.
Whenever new processes (system_process, apps, etc.) are forked from zygote, each of them will have its own independent state which includes this static variable. From then on they will be completely separate things even if it's a variable with the same name, don't get confused by that.
Try adding a Log.i(...) call to write something in both methods, and then check the logcat for the pid in which the messages are logged. I bet you'll see that different pids are writing and reading, and you can't expect them to be doing it in the same global variable.
Click to expand...
Click to collapse
Yes, I realized this. But under handleLoadPackage everything work perfect.
Any suggestion to solve situation?

Falseclock said:
Yes, I realized this. But under handleLoadPackage everything work perfect.
Any suggestion to solve situation?
Click to expand...
Click to collapse
handleLoadPackage is executed after the fork, in the new process. Not sure what exactly you hooked when you tried that way, but probably both callbacks were executed in the same app/process.
You have the typical problem that requires some kind of inter-process communication (IPC). Most common examples for IPC in Android are broadcasts and services. Files might also be an option (especially with observers), but probably not when you need to change the value very frequently.

[Q] Xposed - How to get the package name of a process

Hello,
I'm building an xposed module and i want to hook a method only if certain process (app) called this method. I can get the process pid and uid using Binder, but I can't find a way to get the package name.
How can I get it?
Thanks, Gidi

You can get it the usual way if you have a context. It might be a better idea to do something like this, depending on what you're trying to do:
Java:
public class XposedMod implements IXposedHookLoadPackage {
private int mHookedAppUid; // You can use this field to directly compare the UID.
[user=439709]@override[/user]
public void handleLoadPackage(XC_LoadPackage.LoadPackageParam lpparam) throws Throwable {
if (!lpparam.packageName.equals("package"))
return;
mHookedAppUid = lpparam.appInfo.uid;
}
}

GermainZ said:
You can get it the usual way if you have a context. It might be a better idea to do something like this, depending on what you're trying to do:
Java:
public class XposedMod implements IXposedHookLoadPackage {
private int mHookedAppUid; // You can use this field to directly compare the UID.
[user=439709]@override[/user]
public void handleLoadPackage(XC_LoadPackage.LoadPackageParam lpparam) throws Throwable {
if (!lpparam.packageName.equals("package"))
return;
mHookedAppUid = lpparam.appInfo.uid;
}
}
Click to expand...
Click to collapse
Thanks, but i still can't find a good way to get it.
for my example, i'm trying to hook the method sendTextMessage from android.telephony.SmsManager
if i do it using handleLoadPackage, it doesn't seems to work, but if i do it using initZygote it does work (i'm able to hook the method)
and since i don't have a Context, i can't do it in the usual way, and it seems i'm doing something wrong, since i can't use the other way too...
any idea?

You should use handleLoadPackage for the app you want (e.g. AOSP SMS app), it's independent from the initZygote hook and only there to store the UID.
Otherwise, you can try AndroidAppHelper.currentApplication() to get a context. This may not always return a context, though.

[Q] call startService from hook method

Hello,
I've succeeded to hook method that gives me the accelerometer events.
so now all the application which use the accelerometer are generating events.
I wanted to send all those events from the hooking method to a service using intents that will aggregate them
and write them into a sqlite db (the db is not relevant for now, only the service).
The problem is that i can't start the intentService from the hook method.
Things that i tried already:
-- getting the Context from the activity on load by hooking the onStart in the Activity.class (succeeded getting the context but not starting the Service with an intent)
-- using the same context as above but start a broadcast receiver with implicit intent (define intent-filter in the manifest), and from the
broadcast to start the service (not worked either, the broadcast never got the sent message)
is there some guide or tutorial that can show me how to start a service or broadcast receiver from the hook method?
thanks ahead...

- make sure your service is defined in the manifest
- instead of IntentService, consider using standard service to which you can bind using context.bindService together with ServiceConnection object (see developer.android.com). You can use messenger approach for data exchange. This would be more efficient in your case.
As an example, I am using that approach in the following scenario:
I need to process screenshot taken during screen off in DisplayPowerController using my application context as I need to write image file within my module's filesDir
- I have a service within my module that receives image data and writes them to a file.
- I am binding to this service using bindService from within DisplayPowerController. It sends image data in chunks.
See this commit for more info:
https://github.com/GravityBox/GravityBox/commit/ad09553eaf0c669c4dcb8233a6b9706d1d939761

Call from other app context
First thanks for your answer,
Just to make it clear lets say i don't have any application,
i want to make some monitoring module on my phone which record all the Accelerometer events
request by different apps installed on my phone.
So there is general hook that tracking all the Accelerometer events, but when from those apps
or hook (the apps not mine but some apps i downloaded from the google play store), i want to
start a service or broadcast using their app context (taken from the activity or something).
The broadcast or service will not start (i think something with sandbox or that the apps and the service are not under the same context)
**that what i understood, maybe it's just some mistake in my code**
For example that some test i made:
Main Hook class:
public class TestHook implements IXposedHookLoadPackage{
@override
public void handleLoadPackage(LoadPackageParam lpparam) throws Throwable {
XposedBridge.hookAllMethods(Activity.class,"onStart", new XC_MethodHook()
{
@override
protected void beforeHookedMethod(MethodHookParam param)
throws Throwable {
Context context = (Context)param.thisObject;
if(context != null){
XposedBridge.log("sending brod...");
context.sendBroadcast(new Intent("com.example.logging"));
} else {
XposedBridge.log("not sending");
}
}
});
}
}
The receiver:
public class BrodTest extends BroadcastReceiver{
@override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
Toast.makeText(context, "Got BroadCast", Toast.LENGTH_LONG).show();
}
}
and the manifest:
<manifest xmlns:android=
package="com.example.testproject"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<receiver android:name=".BrodTest">
<intent-filter>
<action android:name="com.example.logging"/>
</intent-filter>
</receiver>
<!--Declaration of the Xposed framework -->
<meta-data
android:name="xposedmodule"
android:value="true" />
<meta-data
android:name="xposedminversion"
android:value="30+" />
<meta-data android:name="xposeddescription"
android:value="Recording Sensors and Transmission events"/>
</application>
</manifest>
just tried to make some hook that will send to broadcast and show Toast message...
Thanks again...

I don't see anything wrong with the code. It should work.
Do you get a log message that the broadcast was sent?

Exported receiver?

Receiver log
The log shows me the sending message to the receiver so i know i have the context correctly,
and i at first put my broadcast exported to false, but than i thought about permissions problem
so i deleted the exported attribute for being exported=true by default..
bottom line, i see the logs messages but not the toast that the receiver should show me...
if there is any other suggestions i be grateful,
thx

Try creating a different receiver with a different class name. Try using fully qualified class name. Also make sure to change intent action string for a new one. Use something more standard like "testproject.intent.action.LOGGING".
Maybe something got messed up while you were changing receiver properties.
This info from doc is interesting:
android:name
Once you publish your application, you*should not change this name*(unless you've setandroid:exported="false").
Click to expand...
Click to collapse
Regarding "exported" attribute. Safely omit it as it defaults to true automatically when you have intent-filter defined.
And maybe also try Log.d() instead of toast and check logcat.

Log.d
about the Log.d you suggested, when i run even with debug mode from eclipse and install the new module
its require me to restart the phone first, how can i debug like normal application?
when i restart the phone the adb is closed and i loose the debugging ability?
thanks anyway i will try it out...

Use adb logcat from command line.

How to hook a method from third party jar?

Hello:
It seems to be an obvious question, but I can't find the answer through google.
I am developing a app using unity3d, the package name is "com.unityproject.coolapp", but I need to use some third party plugin to fullfill some function, say, the package name of the third party plugin(a jar) is com.thirdparty, and the method I want to use is in com.thirdparty.internet.view package, and class name is MagicView, the method name is openAView(String url), something like that.
I successfully inspected the com.unityproject.coolapp, when it's lunching. but I never catch "com.thirdparty" fire. and I try to hook openAView method, I see the log shows no such function err.
here is my code:
if(lpparam.packageName.equals("com.unityproject.coolapp")){
XposedBridge.log("!!!!!!!cool app loaded!!!!!!!");
findAndHookMethod("com.thirdparty.internet.view", lpparam.classLoader, "openAView", String.class, new XC_MethodHook() {
@override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
XposedBridge.log("!!!!!!!open a view hooked!!!!!!!");
}
});
}
I am new to xposed, some help please? Thank you very much.

Is it possible to throw an exception in Xposed hooked method?

Sorry, I can't write in Xposed development thread because I'm new as poster here.
I'm trying to throw an exception in my after hook function, but it doesn't trigger in app that should catch this exception.
For example, I'm trying to throw PackageManager.NameNotFoundException in PackageManager.getPackageInfo(String, int). I forked AndroidEagleEye for easier hook development, disabled all "ignore" try/catches, but my exception isn't triggering my checker app "catch" block anyways.
Code:
@Override
public void after(MethodHookParam param) throws Throwable {
if(mMethod == Methods.getPackageInfo && param.args[0].equals(packageName)){
throw new PackageManager.NameNotFoundException();
}
}
Is throwing an exception through Xposed possible and if it is, how can it be done?

Maybe check and try setThrowable: http://api.xposed.info/reference/de...kParam.html#setThrowable(java.lang.Throwable)

Yeah, it helps, thank you, I shouldn't forget to RTFM.