fix soft reboot caused by KeyStore exception

The Mac handle obtained from AndroidKeyStore is sometimes invalidated by
the AndroidKeyStore based on some LRU technique.

This change make sure that we always get a valid handle.
And adds exception handling to make sure a crash will not happen for the
same reason again.

If KeyStore continuously fails to generate MAC address, we will use
locally generated MAC as it is the next best option.

Bug: 146203882
Test: atest FrameworksWifiTests

Merged-In: I8a3b810ba95898a96d81fe57979db4787e1a46c4
Change-Id: I8a3b810ba95898a96d81fe57979db4787e1a46c4
(cherry-picked from e299359a6e6e9e13217862f7f66627eccbff46ce)

2 files changed, 34 insertions, 5 deletions

diff --git a/tests/wifitests/src/com/android/server/wifi/MacAddressUtilTest.java b/tests/wifitests/src/com/android/server/wifi/MacAddressUtilTest.java
index 253310840..7e598db31 100644
--- a/tests/wifitests/src/com/android/server/wifi/MacAddressUtilTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/MacAddressUtilTest.java
@@ -29,6 +29,7 @@ import org.junit.Test;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
+import java.security.ProviderException;
 import java.util.Random;
 
 import javax.crypto.Mac;
@@ -69,4 +70,18 @@ public class MacAddressUtilTest {
             assertTrue(WifiConfiguration.isValidMacAddressForRandomization(macAddress));
         }
     }
+
+    /**
+     * Verify the java.security.ProviderException is caught.
+     */
+    @Test
+    public void testCalculatePersistentMacCatchesException() {
+        when(mMac.doFinal(any())).thenThrow(new ProviderException("error occurred"));
+        try {
+            WifiConfiguration config = WifiConfigurationTestUtil.createOpenNetwork();
+            assertNull(mMacAddressUtil.calculatePersistentMacForConfiguration(config, mMac));
+        } catch (Exception e) {
+            fail("Exception not caught.");
+        }
+    }
 }
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java b/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
index 23eea328f..6fa1868cb 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
@@ -303,13 +303,27 @@ public class WifiConfigManagerTest {
     }
 
     /**
-     * Verifies that the Mac randomization secret hashfunction is obtained after |loadFromStore|.
+     * Verify that a randomized MAC address is generated even if the KeyStore operation fails.
      */
     @Test
-    public void testMacHashIsObtainedAfterLoadFromStore() {
-        verify(mMacAddressUtil, never()).obtainMacRandHashFunction(anyInt());
-        assertTrue(mWifiConfigManager.loadFromStore());
-        verify(mMacAddressUtil).obtainMacRandHashFunction(anyInt());
+    public void testRandomizedMacIsGeneratedEvenIfKeyStoreFails() {
+        when(mMacAddressUtil.calculatePersistentMacForConfiguration(any(), any())).thenReturn(null);
+
+        // Try adding a network.
+        WifiConfiguration openNetwork = WifiConfigurationTestUtil.createOpenNetwork();
+        List<WifiConfiguration> networks = new ArrayList<>();
+        networks.add(openNetwork);
+        verifyAddNetworkToWifiConfigManager(openNetwork);
+        List<WifiConfiguration> retrievedNetworks =
+                mWifiConfigManager.getConfiguredNetworksWithPasswords();
+
+        // Verify that we have attempted to generate the MAC address twice (1 retry)
+        verify(mMacAddressUtil, times(2)).calculatePersistentMacForConfiguration(any(), any());
+        assertEquals(1, retrievedNetworks.size());
+
+        // Verify that despite KeyStore returning null, we are still getting a valid MAC address.
+        assertNotEquals(WifiInfo.DEFAULT_MAC_ADDRESS,
+                retrievedNetworks.get(0).getRandomizedMacAddress().toString());
     }
 
     /**