Merge changes Ic8632068,I7606dad8

* changes:
  LockSettingsService: reject null keys in setString() et al.
  LockSettingsStorage: gracefully handle null keys in database

services/core/java/com/android/server/locksettings/LockSettingsService.java

@@ -1156,18 +1156,21 @@ public class LockSettingsService extends ILockSettings.Stub {
     @Override
     public void setBoolean(String key, boolean value, int userId) {
         checkWritePermission();
+        Objects.requireNonNull(key);
         mStorage.setBoolean(key, value, userId);
     }
 
     @Override
     public void setLong(String key, long value, int userId) {
         checkWritePermission();
+        Objects.requireNonNull(key);
         mStorage.setLong(key, value, userId);
     }
 
     @Override
     public void setString(String key, String value, int userId) {
         checkWritePermission();
+        Objects.requireNonNull(key);
         mStorage.setString(key, value, userId);
     }
 

services/core/java/com/android/server/locksettings/LockSettingsStorage.java

@@ -62,6 +62,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 /**
  * Storage for the lock settings service.
@@ -886,12 +887,15 @@ class LockSettingsStorage {
                 if (!(obj instanceof CacheKey))
                     return false;
                 CacheKey o = (CacheKey) obj;
-                return userId == o.userId && type == o.type && key.equals(o.key);
+                return userId == o.userId && type == o.type && Objects.equals(key, o.key);
             }
 
             @Override
             public int hashCode() {
-                return key.hashCode() ^ userId ^ type;
+                int hashCode = Objects.hashCode(key);
+                hashCode = 31 * hashCode + userId;
+                hashCode = 31 * hashCode + type;
+                return hashCode;
             }
         }
     }

services/tests/servicestests/src/com/android/server/locksettings/LockSettingsServiceTests.java

@@ -423,6 +423,21 @@ public class LockSettingsServiceTests extends BaseLockSettingsServiceTests {
         checkPasswordHistoryLength(userId, 3);
     }
 
+    @Test(expected=NullPointerException.class)
+    public void testSetBooleanRejectsNullKey() {
+        mService.setBoolean(null, false, 0);
+    }
+
+    @Test(expected=NullPointerException.class)
+    public void testSetLongRejectsNullKey() {
+        mService.setLong(null, 0, 0);
+    }
+
+    @Test(expected=NullPointerException.class)
+    public void testSetStringRejectsNullKey() {
+        mService.setString(null, "value", 0);
+    }
+
     private void checkPasswordHistoryLength(int userId, int expectedLen) {
         String history = mService.getString(LockPatternUtils.PASSWORD_HISTORY_KEY, "", userId);
         String[] hashes = TextUtils.split(history, LockPatternUtils.PASSWORD_HISTORY_DELIMITER);

services/tests/servicestests/src/com/android/server/locksettings/LockSettingsStorageTests.java

@@ -265,6 +265,20 @@ public class LockSettingsStorageTests {
         assertEquals("Cached value didn't match stored value", storage, cached);
     }
 
+    @Test
+    public void testNullKey() {
+        mStorage.setString(null, "value", 0);
+
+        // Verify that this doesn't throw an exception.
+        assertEquals("value", mStorage.readKeyValue(null, null, 0));
+
+        // The read that happens as part of prefetchUser shouldn't throw an exception either.
+        mStorage.clearCache();
+        mStorage.prefetchUser(0);
+
+        assertEquals("value", mStorage.readKeyValue(null, null, 0));
+    }
+
     @Test
     public void testRemoveUser() {
         mStorage.writeKeyValue("key", "value", 0);