Develop Reference

How to check whether an EXTERNAL app has draw-over permissions in Android 7?

I am trying to check whether an external application (i.e. not the one I am writing, but another one running on the debug device) has draw-over permissions. However, regardless of the method I use, I always get "false" as answer, whence I know for certain that said application can draw over other apps. In fact, not only I explicitly gave it permissions through the Settings interface, but I actually witnessed it performing a view overlay.
This is the first method I used:
pm.checkPermission(Manifest.permission.SYSTEM_ALERT_WINDOW, "target.package")
This is the second method I used (packageInfo being the PackageInfo object associated with "target.package"):
boolean requestedPermissionGranted = false;
for (int i = 0; i < packageInfo.requestedPermissions.length; ++i) {
if (packageInfo.requestedPermissions[i].equals(Manifest.permission.SYSTEM_ALERT_WINDOW)) {
requestedPermissionGranted =
(packageInfo.requestedPermissionsFlags[i] & PackageInfo.REQUESTED_PERMISSION_GRANTED) != 0;
break;
}
}
hasPermission = requestedPermissionGranted;
Both expressions return false. By the way, I verified that packageInfo.requestedPermissions actually contains SYSTEM_ALERT_WINDOW.
I searched far and wide, but I could not find any topic that would answer my doubts. I only managed to find threads about how to check an app's own permissions, which I am not interested in.
P.S: I cannot use the shell through getRuntime().exec() and list active windows, as I get permission denied.

How come a GCM permission isn't granted on Android 6?

Background
I'm trying to investigate what an app at the office needs to change about its permissions, in order to support Android 6 nicely.
The problem
I've found which permission needs confirmation and which isn't, except for one :
<uses-permission android:name=".permission.C2D_MESSAGE"/>
It seems that this permission isn't mentioned anywhere that I look for, as one that's not granted automatically and yet I can't find where the user can enable it as a confirmation.
What I tried
In order to find which permissions are granted by default and which aren't , I just called this code:
private void checkPermissionsOfApp(String packageName) {
PackageManager pm = getPackageManager();
try {
final ApplicationInfo applicationInfo = pm.getApplicationInfo(packageName, PackageManager.GET_META_DATA);
Log.d("AppLog", "Listing all permissions of app with PackageName: " + applicationInfo.packageName);
PackageInfo packageInfo = pm.getPackageInfo(applicationInfo.packageName, PackageManager.GET_PERMISSIONS);
//Get Permissions
String[] requestedPermissions = packageInfo.requestedPermissions;
if (requestedPermissions != null) {
for (String permission : requestedPermissions) {
boolean permissionGranted = pm.checkPermission(permission, packageName) == PackageManager.PERMISSION_GRANTED;
Log.d("AppLog", "permission:" + permission + " permissionGranted:" + permissionGranted);
}
}
} catch (NameNotFoundException e) {
e.printStackTrace();
}
}
And the call:
checkPermissionsOfApp(getPackageName());
Using the above code, it crashes for the problematic permission, but when using ContextCompat.checkSelfPermission it says it's not granted.
The question
How could it be?
How can I grant the app this permission?
Is it mentioned anywhere?

The documentation, which was updated in October of 2015, still indicates that you need the signature permission.
See also Not receiving push notifications from GCM (Android)
As #CommonsWare mentioned, this does not appear to be part of the new runtime permission checking, or at least is not considered a "dangerous" permission, and so should be automatically granted.

ok, I'm not sure why it is this way, but the permission is said to be granted only if :
The package name of the app is its prefix
you also declare the permission, as such:
<permission
android:name="com.example.user.androidmtest.permission.C2D_MESSAGE"
android:protectionLevel="signature"/>
The weird thing is that even though the code said that the permission is not granted when not adding the package name, it worked on the app.

Can an app determine the other apps that are on the phone and what permissions they have?

I'm wondering if an app has access to the info that shows the other apps on the phone and what permissions they have (i.e. access to your location, contacts, etc). Could I create an app with a feature that displays other apps and their permissions? I know the user can view this info via settings, but I'm wondering if it can be organized and displayed by an app.

Yes. Use the PackageManager. Call GetInstalledPackages to list the installed packages, and then check the requestedPermissions field to see the permissions for each package.
Note: the method below assumes this refers to an Activity.
private void getAppPermissions() {
List<PackageInfo> apps = this.getPackageManager().getInstalledPackages(PackageManager.GET_PERMISSIONS);
for (PackageInfo app : apps) {
String appInfo = app.packageName + ": ";
String[] permissions = app.requestedPermissions;
if (null == permissions) {
appInfo += "no permissions requested\n";
} else {
for (String permission : app.requestedPermissions) {
appInfo += "\n " + permission;
}
}
Log.v("App Permissions", appInfo);
}
}
You may wish to filter the list of returned packages as per this question.

Yes you can. For Android, you just go to Settings > Applications
And you just tap on the application that you want to check, and on the bottom it should say the permissions the app possesses.
For ios, you go to Settings > Privacy
And you tap on the desired type of permission, and you can see the apps that have that permission.

Is there a way for testing Permissions in Android Eclipse?

Hi there I am making my app and I am worried that I might have left some permissions out and can really never be sure I have used the right permissions can you put in any sort of code to see what my app is actually using? or something like that as it is always a guessing game for me when selecting my permissions as I can never be sure.
Heres an example I make a "Check for Updates" Button. From that I launch an Intent to go to my app in the market is that using the internet connection ? or am I just using an Intent because some people will not have a working data connection so would I have to write access full network or something like that? Its just really confusing me

I think u have to check it during testing phase of apps.if there is not proper permissions given by u then the apps give error and u can add proper permission according to error.

Here is an example to walk through permissions:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
PackageManager pm = getPackageManager();
try {
PackageInfo pi = pm.getPackageInfo("<INTERESTING PACKAGE NAME>", PackageManager.GET_PERMISSIONS);
if ((null == pi.requestedPermissions) ||
(pi.requestedPermissions.length == 0)) {
Log.d("NOTE", "Package has NO permissions!");
return;
}
for (int i = 0; i < pi.requestedPermissions.length; ++i) {
Log.d("NOTE", pi.requestedPermissions[i] + " " + checkCallingOrSelfPermission(pi.requestedPermissions[i]));
}
} catch (NameNotFoundException e) {
Log.d("ERR", "Package name is wrong!");
}
}
Edit: your question seems to ask what permissions your app is using; this code tells your app what permissions you've requested. If you want to know what is being used, you need to strip all permissions from your app (which will cause runtime errors if you actually need any of them), and then through reading error logs and/or incrementally adding permissions until things work correctly, determine by hand what is actually needed.

Android checkCallingOrSelfPermission not returning properly

I am writing a service which needs to see if its caller holds a particular private permission. I do not want to prevent callers that lack this permission, I only want to know the status so that I can react accordingly. It would seem that the Context method checkCallingPermission() is perfect for what I need, returning 0 if the caller has the specified permission and -1 otherwise. I'm finding that -1 is returned in all cases though.
I wrote a test case (using the similar method checkCallingOrSelfPermission() where I pulled my package's PackageInfo from the system, enumerated each of my permissions (only one requested for the package), and display the result of checkCallingOrSelfPermission(). Since the permissions I'm checking against in this case are exactly the permissions I hold, I would expect checkCallingOrSelfPermission() to return 0 (PackageManager.PERMISSION_GRANTED) only... buy it only returns -1 (PackageManager.PERMISSION_DENIED).
I've checked this and received the same results on both a 4.0 emulator and a 2.3 device.
Any idea what I'm doing wrong to cause these calls to fail?
My test manifest includes:
<permission
android:protectionLevel="signatureOrSystem"
android:name="abcd" />
<uses-permission android:name="abcd" />
My test activity code is:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
PackageManager pm = getPackageManager();
try {
PackageInfo pi = pm.getPackageInfo("com.test.check", PackageManager.GET_PERMISSIONS);
if ((null == pi.requestedPermissions) ||
(pi.requestedPermissions.length == 0)) {
Log.d("CHECK", "Package has NO permissions!");
finish();
return;
}
for (int i = 0; i < pi.requestedPermissions.length; ++i) {
Log.d("CHECK", pi.requestedPermissions[i] + " " + checkCallingOrSelfPermission(pi.requestedPermissions[i]));
}
} catch (NameNotFoundException e) {
Log.d("CHECK", "Package name is wrong!");
}
finish();
}
and my test results are:
D/CHECK ( 3600): abcd -1

I have not been able to resolve this within the scope of my service needing to check permissions, but I have found a work-around for the service (and a problem in my test case).
My test case failed because the permission I created and checked with, "abcd", was renamed by Android in the <permission> entry, however Android failed to equally rename it in the <uses-permission> entry. It was renamed to have my package name prepended to it (and this renaming does not occur if I provide a name including a period in it, such as "test.abcd").
Though changing the permission name fixed my test case, my actual case within a service was already using a fully qualified permission name and checkCallingPermission() continues to fail. I discovered, however, that the PackageManager's checkPermission() method does work as expected (at the expense of my needing to retrieve the name of the caller's package).
So to summarize, the following does not work correctly (though I do not know why):
boolean permission = (PackageManager.PERMISSION_GRANTED == checkCallingPermission(PERMISSION_NAME));
while this seems to work correctly:
PackageManager pm = getPackageManager();
boolean permission = (PackageManager.PERMISSION_GRANTED == pm.checkPermission(PERMISSION_NAME, pm.getNameForUid(getCallingUid())));