Allow apps to getProviders() without location permissions.

This restores MR0's behavior in this regard - apps calling
LocationManager.getProviders() or LocationManager.getBestProvider()
will no longer receive a SecurityException if they do not have
any location permissions. Instead, as was the behavior in MR0, they
only receive providers that their permissions grant them access to,
including an empty list if they have no permission whatsoever.

Bug: 7207864
Change-Id: I027df425e258d436c4821c34a25bc46a2a292824

Author: Victoria Lease

services/java/com/android/server/LocationManagerService.java

@@ -601,6 +601,23 @@ private void checkGeofencePermission() {
         }
     }
 
+    private boolean isAllowedProviderSafe(String provider) {
+        if (LocationManager.GPS_PROVIDER.equals(provider) ||
+                LocationManager.PASSIVE_PROVIDER.equals(provider)) {
+            // gps and passive providers require FINE permission
+            return mContext.checkCallingOrSelfPermission(ACCESS_FINE_LOCATION)
+                    == PackageManager.PERMISSION_GRANTED;
+        } else if (LocationManager.NETWORK_PROVIDER.equals(provider) ||
+                LocationManager.FUSED_PROVIDER.equals(provider)) {
+            // network and fused providers are ok with COARSE or FINE
+            return (mContext.checkCallingOrSelfPermission(ACCESS_FINE_LOCATION)
+                    == PackageManager.PERMISSION_GRANTED) ||
+                    (mContext.checkCallingOrSelfPermission(ACCESS_COARSE_LOCATION)
+                    == PackageManager.PERMISSION_GRANTED);
+        }
+        return false;
+    }
+
     /**
      * Returns all providers by name, including passive, but excluding
      * fused.
@@ -632,8 +649,6 @@ public List<String> getAllProviders() {
      */
     @Override
     public List<String> getProviders(Criteria criteria, boolean enabledOnly) {
-        checkPermission();
-
         ArrayList<String> out;
         synchronized (mLock) {
             out = new ArrayList<String>(mProviders.size());
@@ -642,14 +657,16 @@ public List<String> getProviders(Criteria criteria, boolean enabledOnly) {
                 if (LocationManager.FUSED_PROVIDER.equals(name)) {
                     continue;
                 }
-                if (enabledOnly && !isAllowedBySettingsLocked(name)) {
-                    continue;
-                }
-                if (criteria != null && !LocationProvider.propertiesMeetCriteria(
-                        name, provider.getProperties(), criteria)) {
-                    continue;
+                if (isAllowedProviderSafe(name)) {
+                    if (enabledOnly && !isAllowedBySettingsLocked(name)) {
+                        continue;
+                    }
+                    if (criteria != null && !LocationProvider.propertiesMeetCriteria(
+                            name, provider.getProperties(), criteria)) {
+                        continue;
+                    }
+                    out.add(name);
                 }
-                out.add(name);
             }
         }
 
@@ -660,23 +677,22 @@ public List<String> getProviders(Criteria criteria, boolean enabledOnly) {
     /**
      * Return the name of the best provider given a Criteria object.
      * This method has been deprecated from the public API,
-     * and the whole LoactionProvider (including #meetsCriteria)
+     * and the whole LocationProvider (including #meetsCriteria)
      * has been deprecated as well. So this method now uses
      * some simplified logic.
      */
     @Override
     public String getBestProvider(Criteria criteria, boolean enabledOnly) {
         String result = null;
-        checkPermission();
 
         List<String> providers = getProviders(criteria, enabledOnly);
-        if (providers.size() < 1) {
+        if (!providers.isEmpty()) {
             result = pickBest(providers);
             if (D) Log.d(TAG, "getBestProvider(" + criteria + ", " + enabledOnly + ")=" + result);
             return result;
         }
         providers = getProviders(null, enabledOnly);
-        if (providers.size() >= 1) {
+        if (!providers.isEmpty()) {
             result = pickBest(providers);
             if (D) Log.d(TAG, "getBestProvider(" + criteria + ", " + enabledOnly + ")=" + result);
             return result;