diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index f1cff81..0124ee1 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -17,6 +17,7 @@
 package com.android.phone;
 
 import static android.content.pm.PackageManager.PERMISSION_GRANTED;
+import static android.telephony.TelephonyManager.HAL_SERVICE_NETWORK;
 import static android.telephony.TelephonyManager.HAL_SERVICE_RADIO;
 
 import static com.android.internal.telephony.PhoneConstants.PHONE_TYPE_CDMA;
@@ -377,6 +378,9 @@
     private static final int SELECT_P2 = 0;
     private static final int SELECT_P3 = 0x10;
 
+    // Toggling null cipher and integrity support was added in IRadioNetwork 2.1
+    private static final int MIN_NULL_CIPHER_AND_INTEGRITY_VERSION = 201;
+
     /** The singleton instance. */
     private static PhoneInterfaceManager sInstance;
     private static List<String> sThermalMitigationAllowlistedPackages = new ArrayList<>();
@@ -2418,6 +2422,11 @@
         publish();
     }
 
+    @VisibleForTesting
+    public SharedPreferences getSharedPreferences() {
+        return mTelephonySharedPreferences;
+    }
+
     private Phone getDefaultPhone() {
         Phone thePhone = getPhone(getDefaultSubscription());
         return (thePhone != null) ? thePhone : PhoneFactory.getDefaultPhone();
@@ -3634,10 +3643,21 @@
      *
      * @throws SecurityException if the caller does not have the required permission
      */
-    private void enforceModifyPermission() {
+    @VisibleForTesting
+    public void enforceModifyPermission() {
         mApp.enforceCallingOrSelfPermission(android.Manifest.permission.MODIFY_PHONE_STATE, null);
     }
 
+    /**
+     * Make sure the caller has the MODIFY_PHONE_STATE permission.
+     *
+     * @throws SecurityException if the caller does not have the required permission
+     */
+    @VisibleForTesting
+    public void enforceReadPermission() {
+        mApp.enforceCallingOrSelfPermission(android.Manifest.permission.READ_PHONE_STATE, null);
+    }
+
     private void enforceActiveEmergencySessionPermission() {
         mApp.enforceCallingOrSelfPermission(
                 android.Manifest.permission.READ_ACTIVE_EMERGENCY_SESSION, null);
@@ -11654,6 +11674,57 @@
     }
 
     /**
+     * Set whether the device is able to connect with null ciphering or integrity
+     * algorithms. This is a global setting and will apply to all active subscriptions
+     * and all new subscriptions after this.
+     *
+     * @param enabled when true, null  cipher and integrity algorithms are allowed.
+     * @hide
+     */
+    @Override
+    @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE)
+    public void setNullCipherAndIntegrityEnabled(boolean enabled) {
+        enforceModifyPermission();
+        checkForNullCipherAndIntegritySupport();
+
+        // Persist the state of our preference. Each GsmCdmaPhone instance is responsible
+        // for listening to these preference changes and applying them immediately.
+        SharedPreferences.Editor editor = mTelephonySharedPreferences.edit();
+        editor.putBoolean(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED, enabled);
+        editor.apply();
+
+        for (Phone phone: PhoneFactory.getPhones()) {
+            phone.handleNullCipherEnabledChange();
+        }
+    }
+
+
+    /**
+     * Get whether the device is able to connect with null ciphering or integrity
+     * algorithms. Note that this retrieves the phone-global preference and not
+     * the state of the radio.
+     *
+     * @throws SecurityException if {@link permission#MODIFY_PHONE_STATE} is not satisfied
+     * @throws UnsupportedOperationException if the device does not support the minimum HAL
+     * version for this feature.
+     * @hide
+     */
+    @Override
+    @RequiresPermission(android.Manifest.permission.READ_PHONE_STATE)
+    public boolean isNullCipherAndIntegrityPreferenceEnabled() {
+        enforceReadPermission();
+        checkForNullCipherAndIntegritySupport();
+        return getDefaultPhone().getNullCipherAndIntegrityEnabledPreference();
+    }
+
+    private void checkForNullCipherAndIntegritySupport() {
+        if (getHalVersion(HAL_SERVICE_NETWORK) < MIN_NULL_CIPHER_AND_INTEGRITY_VERSION) {
+            throw new UnsupportedOperationException(
+                    "Null cipher and integrity operations require HAL 2.1 or above");
+        }
+    }
+
+    /**
      * Get the SIM state for the slot index.
      * For Remote-SIMs, this method returns {@link IccCardConstants.State#UNKNOWN}
      *
diff --git a/tests/src/com/android/phone/PhoneInterfaceManagerTest.java b/tests/src/com/android/phone/PhoneInterfaceManagerTest.java
index 3b6d5ee..6e4a65f 100644
--- a/tests/src/com/android/phone/PhoneInterfaceManagerTest.java
+++ b/tests/src/com/android/phone/PhoneInterfaceManagerTest.java
@@ -17,15 +17,21 @@
 package com.android.phone;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
-import android.content.pm.PackageManager;
+import android.content.SharedPreferences;
 import android.content.res.Resources;
 import android.telephony.RadioAccessFamily;
 import android.telephony.TelephonyManager;
@@ -50,22 +56,24 @@
 @RunWith(AndroidJUnit4.class)
 public class PhoneInterfaceManagerTest extends TelephonyTestBase {
     private PhoneInterfaceManager mPhoneInterfaceManager;
+    private SharedPreferences mSharedPreferences;
 
     @Mock
     PhoneGlobals mPhoneGlobals;
     @Mock
     Phone mPhone;
-    @Mock
-    PackageManager mPackageManager;
 
     @Before
     @UiThreadTest
     public void setUp() throws Exception {
         super.setUp();
-        doReturn(mPackageManager).when(mPhoneGlobals).getPackageManager();
-        doReturn(false).when(mPackageManager).hasSystemFeature(
-                PackageManager.FEATURE_TELEPHONY_IMS);
-        mPhoneInterfaceManager = PhoneInterfaceManager.init(mPhoneGlobals);
+        // Note that PhoneInterfaceManager is a singleton. Calling init gives us a handle to the
+        // global singleton, but the context that is passed in is unused if the phone app is already
+        // alive on a test devices. You must use the spy to mock behavior. Mocks stemming from the
+        // passed context will remain unused.
+        mPhoneInterfaceManager = spy(PhoneInterfaceManager.init(mPhoneGlobals));
+        mSharedPreferences = mPhoneInterfaceManager.getSharedPreferences();
+        mSharedPreferences.edit().remove(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED).commit();
     }
 
     @Test
@@ -138,4 +146,81 @@
 
         assertEquals("ff-Latn-BF", resultFfBf);
     }
+
+    @Test
+    public void setNullCipherAndIntegrityEnabled_successfullyEnable() {
+        doReturn(201).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doNothing().when(mPhoneInterfaceManager).enforceModifyPermission();
+        assertFalse(mSharedPreferences.contains(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED));
+
+        mPhoneInterfaceManager.setNullCipherAndIntegrityEnabled(true);
+
+        assertTrue(
+                mSharedPreferences.getBoolean(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED, false));
+    }
+
+    @Test
+    public void setNullCipherAndIntegrityEnabled_successfullyDisable() {
+        doReturn(201).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doNothing().when(mPhoneInterfaceManager).enforceModifyPermission();
+        assertFalse(mSharedPreferences.contains(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED));
+
+        mPhoneInterfaceManager.setNullCipherAndIntegrityEnabled(false);
+
+        assertFalse(
+                mSharedPreferences.getBoolean(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED, true));
+    }
+
+    @Test
+    public void setNullCipherAndIntegrityEnabled_lackingNecessaryHal() {
+        doReturn(101).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doNothing().when(mPhoneInterfaceManager).enforceModifyPermission();
+
+        assertThrows(UnsupportedOperationException.class, () -> {
+            mPhoneInterfaceManager.setNullCipherAndIntegrityEnabled(true);
+        });
+
+    }
+
+    @Test
+    public void setNullCipherAndIntegrityEnabled_lackingPermissions() {
+        doReturn(201).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doThrow(SecurityException.class).when(mPhoneInterfaceManager).enforceModifyPermission();
+
+        assertThrows(SecurityException.class, () -> {
+            mPhoneInterfaceManager.setNullCipherAndIntegrityEnabled(true);
+        });
+    }
+
+    @Test
+    public void isNullCipherAndIntegrityPreferenceEnabled() {
+        doReturn(201).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doNothing().when(mPhoneInterfaceManager).enforceModifyPermission();
+
+        assertTrue(mPhoneInterfaceManager.isNullCipherAndIntegrityPreferenceEnabled());
+        mPhoneInterfaceManager.setNullCipherAndIntegrityEnabled(false);
+        assertFalse(
+                mSharedPreferences.getBoolean(Phone.PREF_NULL_CIPHER_AND_INTEGRITY_ENABLED, true));
+    }
+
+    @Test
+    public void isNullCipherAndIntegrityPreferenceEnabled_lackingNecessaryHal() {
+        doReturn(101).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doNothing().when(mPhoneInterfaceManager).enforceModifyPermission();
+
+        assertThrows(UnsupportedOperationException.class, () -> {
+            mPhoneInterfaceManager.isNullCipherAndIntegrityPreferenceEnabled();
+        });
+
+    }
+
+    @Test
+    public void isNullCipherAndIntegrityPreferenceEnabled_lackingPermissions() {
+        doReturn(201).when(mPhoneInterfaceManager).getHalVersion(anyInt());
+        doThrow(SecurityException.class).when(mPhoneInterfaceManager).enforceReadPermission();
+
+        assertThrows(SecurityException.class, () -> {
+            mPhoneInterfaceManager.isNullCipherAndIntegrityPreferenceEnabled();
+        });
+    }
 }