Develop Reference

Permission Denied while sending <protected-broadcast> from an app in /System/app

I am getting:
java.lang.SecurityException: Permission Denial: not allowed to send broadcast android.intent.action.TIME_SET from pid=xxxxx, uid=xxxxx
for:
Intent timeChanged = new Intent(Intent.ACTION_TIME_CHANGED);
sendBroadcast(timeChanged);
even when I have put my app in /system/app folder. Please help me out to know why this is happening?

Try putting the app in the priv-app folder in the system partition,
and adding the app to the privapp-permissions.xml file on the same partition, with the TIME_SET permission.

Please come here: Permission Denial of android.intent.action.REBOOT for APP in /system/priv-app. To get the most recent version of the code, just replace "android-5.1.1_r20" with "master").
It seems the app must be a persistent app, which can be done by setting the persistent flag to true on the Application tag of the Manifest. Either that, or have a UserId whitelisted, which is also on the code (though, sharedUserId is deprecated as of API 29, so might not be a good idea to use that way).

I cannot grant the following permission on my app..Kindly suggest any alternative?

<uses-permission android:name="android.permission.CALL_PRIVILEGED"/>
I cannot grant this permission in the android manifest file as it shows the following
error:
Permissions with the protection level signature or signatureOrSystem are only granted to system apps. If an app is a regular non-system app, it will never be able to use these permissions.
So,what should i do now?

Permissions with the protection level signature or signatureOrSystem
are only granted to system apps. If an app is a regular non-system
app, it will never be able to use these permissions.
So,what should i do now?
If your app is expected to run on non-rooted devices, then you're simply doomed - you can do nothing, unless you have platform keys to sign your app with it.
Alternatively, you may narrow your audience to rooted devices only but that would allow you to do what you want incl. using features usually reserved for the platform or system apps ony.
Finally you may rethink your approach. Perhaps what you want to do can be achieved other way, w/o need of elevating app privileges.

For this "CALL_PRIVILEGED" permission , you will need a rooted device and the app must be installed as a system app only.

From the documentation (https://developer.android.com/reference/android/Manifest.permission.html#CALL_PRIVILEGED):
String CALL_PRIVILEGED
Allows an application to call any phone number, including emergency numbers,
without going through the Dialer user interface for the user to confirm the
call being placed.
Not for use by third-party applications.
So, the short answer is that you can't use it. What are you trying to accomplish?

Unable to grant SET_ANIMATION_SCALE permission programmatically

I need to grant my device permission to change automation settings of the device it is running on (for testing purpose).
I have added to manifest:
<uses-permission android:name="android.permission.SET_ANIMATION_SCALE"/>
And in my Activity on resume:
String[] permissions = new String[1];
permissions[0] = Manifest.permission.SET_ANIMATION_SCALE;
ActivityCompat.requestPermissions(getCurrentActivity(), permissions, 0);
Log.d("ISGRANTED", " " + (ContextCompat.checkSelfPermission(getCurrentActivity(), permissions[0]) == PackageManager.PERMISSION_GRANTED));
And nothing happens. I test on Android Api 23+ and I don't get any dialog to get the permission. Log returns:
06-30 15:03:32.757 17771-17799/my.app.package D/ISGRANTED: false
But if I replace permisions[0] with Manifest.permission.GET_ACCOUNTS (which is also in my manifest above SET_ANIMATION_SCALE permission) then it works. Dialog appears and log returns true.
What's the problem?

Please take a look at my Gradle plugin, Cappuccino. It automates the process of disabling system animations for Espresso testing. There are detailed instructions on Github.

From here or here, because it's not for use by third-party applications:
"android.permission.SET_ANIMATION_SCALE" : ["signature|system|development", "Modify the global animation scaling factor. Not for use by third-party applications."],
ProtectionLevel (from here):
signature 2 A permission that the system is to grant only if the requesting application is signed with the same certificate as the application that declared the permission. If the certificates match, the system automatically grants the permission without notifying the user or asking for the user's explicit approval.
system 0x10 Old synonym for "privileged".
privileged 0x10 Additional flag from base permission type: this permission can also be granted to any applications installed as privileged apps on the system image. Please avoid using this option, as the signature protection level should be sufficient for most needs and works regardless of exactly where applications are installed. This permission flag is used for certain special situations where multiple vendors have applications built in to a system image which need to share specific features explicitly because they are being built together.
development 0x20 Additional flag from base permission type: this permission can also (optionally) be granted to development applications.

Android Marshmallow, "dangerous" protection level and system components/apps

I'm developing an application that going to be pr-installed (as a system app) on the firmware.
from the documentation so far about the relation between system apps, new permissions model, and the protection levels - I don't understand exactly when system app needs (if at all) to request user permission.
My problems starts when I try to use the WRITE_EXTERNAL_STORAGE permission. from the documentation I can see that it marked as "dangerous" permission.
- does "dangerous" permissions grant automatically to system apps?
when I use WRITE_EXTERNAL_STORAGE permission (as a system app) I'm getting security exception, and I don't know if it's mean that even tough my app installed as a system app - "dangerous" permissions must be requested by the user..
another point to mention:
to check the app behavior as a system app, I'm installing my application APK on the sys-priv directory (the device is rooted) of a nexus 5 running SDK preview 3. this is when I'm getting the security exception when attep to use methods requires the external storage permission..

After a lot of digging and debugging, I finally found some clue of granting runtime permission on marshmallow for system app, with a lot of inspirations in this stackoverflow ticket.
The key logic is in DefaultPermissionGrantPolicy. After systemReady, PackageManagerService checks if this user's default runtime permissions are not set yet(i.e. this is a new user), if so, PackageManagerService calls DefaultPermissionGrantPolicy.grantDefaultPermissions() to check/grant permissions:
public void grantDefaultPermissions(int userId) {
grantPermissionsToSysComponentsAndPrivApps(userId);
grantDefaultSystemHandlerPermissions(userId);
}
There are two cases that your built-in app may be automatically granted with runtime permission.
A> grantPermissionsToSysComponentsAndPrivApps -> will grant runtime permission with FLAG_PERMISSION_SYSTEM_FIXED and FLAG_PERMISSION_GRANTED_BY_DEFAULT.
if your system app has uid<10000, you will be granted with permissions for your user group.
if your system app fits all below conditions, it will be granted the permissions.
is a privilegedApp (under /system/priv-app/)
is persistent (android:persistent="true")
signed with platform signature.
B> grantDefaultSystemHandlerPermissions -> will grant runtime permission with FLAG_PERMISSION_GRANTED_BY_DEFAULT .
If your app is considered as a "default platform handler app", (i.e. your app is "expected to work out-of-the-box", like camera, dialer, SMS, calendar .etc, you can read more in method grantDefaultSystemHandlerPermissions()).
Other than that, your system application needs to ask user for granting dangerous permission, as long as it has targetSdk set to 23.

Quoting the release notes for the 2nd M preview:
Apps included in the system image are no longer granted dangerous permissions automatically. All apps should check for and request permissions at runtime.
That fits with what I recall seeing when I first used the stock Camera app on a Nexus 5 with the final(?) 6.0 preview firmware — it too asked for the runtime permission.
So, AFAIK, system apps have to ask for runtime permissions, as do non-system apps.

Security Exception: Permission denial for DEVICE_POWER

I am trying to write a simple android app that switches off my phone screen. When I am runnning this app I get Security Exception: Permission denial app requires android.permission.DEVICE_POWER. I know that this is a protected permission but my phone is rooted. What do I specify that I can use this permission? I have already tried declaring DEVICE_ADMIN permssion along with the DEVICE_POWER permission but it still doesn't work.

Rooting potentially lets you circumvent or modify the android security model, but it doesn't necessarily mean you get special privileges for an android API which enforces it. You cannot ordinarily run an application itself as root, while code in a helper executable which you could start as root will have substantial difficulty interacting with the Android APIs.
What you are trying to do may really not be a very good idea. But if you really want to do it, you would need to either install your own build of Android so that you have a (self generated) key matching that which you used to sign the platform, which you can then use to sign your application, or else try to install your application on the system partition.

If all you want to do is turn the screen off, then why don't you use the PowerManager? According to the documentation, the goToSleep() function will force the device to go to sleep.