Fix country code setting for non-US locales

Changes in the CL:
a) Always use "US" locale for converting the country code to upper case
in WifiCountryCode.
b) The HIDL interface for country code setter expects 2 bytes only. Tighten
the error checks before invoking the HIDL call in SupplicantStaIfaceHal.

Bug: 110670437
Test: Unit tests
Test: Able to connect to wifi networks & bringup softap.
Change-Id: I01a7f139cb8060f67b652e13dbb38e6dafe0ee4c

4 files changed, 63 insertions, 3 deletions

diff --git a/service/java/com/android/server/wifi/SupplicantStaIfaceHal.java b/service/java/com/android/server/wifi/SupplicantStaIfaceHal.java
index 5bf44ce66..2c9b5e5ec 100644
--- a/service/java/com/android/server/wifi/SupplicantStaIfaceHal.java
+++ b/service/java/com/android/server/wifi/SupplicantStaIfaceHal.java
@@ -1853,7 +1853,9 @@ public class SupplicantStaIfaceHal {
     public boolean setCountryCode(@NonNull String ifaceName, String codeStr) {
         synchronized (mLock) {
             if (TextUtils.isEmpty(codeStr)) return false;
-            return setCountryCode(ifaceName, NativeUtil.stringToByteArray(codeStr));
+            byte[] countryCodeBytes = NativeUtil.stringToByteArray(codeStr);
+            if (countryCodeBytes.length != 2) return false;
+            return setCountryCode(ifaceName, countryCodeBytes);
         }
     }
 
diff --git a/service/java/com/android/server/wifi/WifiCountryCode.java b/service/java/com/android/server/wifi/WifiCountryCode.java
index 04bd38bda..41a366dbf 100644
--- a/service/java/com/android/server/wifi/WifiCountryCode.java
+++ b/service/java/com/android/server/wifi/WifiCountryCode.java
@@ -21,6 +21,7 @@ import android.util.Log;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
+import java.util.Locale;
 
 /**
  * Provide functions for making changes to WiFi country code.
@@ -51,7 +52,7 @@ public class WifiCountryCode {
         mRevertCountryCodeOnCellularLoss = revertCountryCodeOnCellularLoss;
 
         if (!TextUtils.isEmpty(oemDefaultCountryCode)) {
-            mDefaultCountryCode = oemDefaultCountryCode.toUpperCase();
+            mDefaultCountryCode = oemDefaultCountryCode.toUpperCase(Locale.US);
         } else {
             if (mRevertCountryCodeOnCellularLoss) {
                 Log.w(TAG, "config_wifi_revert_country_code_on_cellular_loss is set, "
@@ -122,7 +123,7 @@ public class WifiCountryCode {
                 mTelephonyCountryCode = null;
             }
         } else {
-            mTelephonyCountryCode = countryCode.toUpperCase();
+            mTelephonyCountryCode = countryCode.toUpperCase(Locale.US);
         }
         // If wpa_supplicant is ready we set the country code now, otherwise it will be
         // set once wpa_supplicant is ready.
diff --git a/tests/wifitests/src/com/android/server/wifi/SupplicantStaIfaceHalTest.java b/tests/wifitests/src/com/android/server/wifi/SupplicantStaIfaceHalTest.java
index b4ea5af34..33490869b 100644
--- a/tests/wifitests/src/com/android/server/wifi/SupplicantStaIfaceHalTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/SupplicantStaIfaceHalTest.java
@@ -1515,6 +1515,33 @@ public class SupplicantStaIfaceHalTest {
         verify(mISupplicantStaIfaceMock).startWpsPbc(eq(anyBssidBytes));
     }
 
+    /**
+     * Tests country code setter
+     */
+    @Test
+    public void testSetCountryCode() throws Exception {
+        when(mISupplicantStaIfaceMock.setCountryCode(any(byte[].class))).thenReturn(mStatusSuccess);
+        String testCountryCode = "US";
+
+        // Fail before initialization is performed.
+        assertFalse(mDut.setCountryCode(WLAN0_IFACE_NAME, testCountryCode));
+        verify(mISupplicantStaIfaceMock, never()).setCountryCode(any(byte[].class));
+
+        executeAndValidateInitializationSequence();
+
+        assertTrue(mDut.setCountryCode(WLAN0_IFACE_NAME, testCountryCode));
+        verify(mISupplicantStaIfaceMock).setCountryCode(eq(testCountryCode.getBytes()));
+
+        // Bad input values should fail the call.
+        reset(mISupplicantStaIfaceMock);
+
+        assertFalse(mDut.setCountryCode(WLAN0_IFACE_NAME, null));
+        verify(mISupplicantStaIfaceMock, never()).setCountryCode(any(byte[].class));
+
+        assertFalse(mDut.setCountryCode(WLAN0_IFACE_NAME, "U"));
+        verify(mISupplicantStaIfaceMock, never()).setCountryCode(any(byte[].class));
+    }
+
     private WifiConfiguration createTestWifiConfiguration() {
         WifiConfiguration config = new WifiConfiguration();
         config.networkId = SUPPLICANT_NETWORK_ID;
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiCountryCodeTest.java b/tests/wifitests/src/com/android/server/wifi/WifiCountryCodeTest.java
index 4ce5d5e40..95554bc63 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiCountryCodeTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiCountryCodeTest.java
@@ -17,6 +17,7 @@
 package com.android.server.wifi;
 
 import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.anyString;
 import static org.mockito.Mockito.times;
@@ -30,6 +31,8 @@ import org.junit.Test;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
+import java.util.Locale;
+
 /**
  * Unit tests for {@link com.android.server.wifi.WifiCountryCode}.
  */
@@ -166,4 +169,31 @@ public class WifiCountryCodeTest {
         assertEquals(mTelephonyCountryCode, mWifiCountryCode.getCountryCode());
     }
 
+    /**
+     * Tests that we always use the US locale for converting the provided country code regardless
+     * of the system locale set.
+     */
+    @Test
+    public void useUSLocaleForConversionToUpperCase() {
+        String oemCountryCodeLower = "us";
+        String oemCountryCodeUpper = "US";
+        String telephonyCountryCodeLower = "il";
+        String telephonyCountryCodeUpper = "IL";
+
+        mWifiCountryCode = new WifiCountryCode(
+                mWifiNative,
+                oemCountryCodeLower,
+                mRevertCountryCodeOnCellularLoss);
+
+        // Set the default locale to "tr" (Non US).
+        Locale.setDefault(new Locale("tr"));
+
+        // Trigger a country code change using the OEM country code.
+        mWifiCountryCode.setReadyForChange(true);
+        verify(mWifiNative).setCountryCode(any(), eq(oemCountryCodeUpper));
+
+        // Now trigger a country code change using the telephony country code.
+        mWifiCountryCode.setCountryCode(telephonyCountryCodeLower);
+        verify(mWifiNative).setCountryCode(any(), eq(telephonyCountryCodeUpper));
+    }
 }