Provide last known cell id for emergency call

Provide last known cell id to connection service
for emergency calls.

Bug: 198533763
Test: unit test
Change-Id: I8b660c0b5fbe095e3b9b67129b7404ebd7ec5ccd

core/api/current.txt

@@ -39988,6 +39988,7 @@ package android.telecom {
     field public static final String EXTRA_CHILD_ADDRESS = "android.telecom.extra.CHILD_ADDRESS";
     field public static final String EXTRA_IS_RTT_AUDIO_PRESENT = "android.telecom.extra.IS_RTT_AUDIO_PRESENT";
     field public static final String EXTRA_LAST_FORWARDED_NUMBER = "android.telecom.extra.LAST_FORWARDED_NUMBER";
+    field public static final String EXTRA_LAST_KNOWN_CELL_IDENTITY = "android.telecom.extra.LAST_KNOWN_CELL_IDENTITY";
     field public static final String EXTRA_SIP_INVITE = "android.telecom.extra.SIP_INVITE";
     field public static final int PROPERTY_ASSISTED_DIALING = 512; // 0x200
     field public static final int PROPERTY_CROSS_SIM = 8192; // 0x2000

telecomm/java/android/telecom/Connection.java

@@ -821,6 +821,17 @@ public abstract class Connection extends Conferenceable {
     public static final String EXTRA_AUDIO_CODEC_BANDWIDTH_KHZ =
             "android.telecom.extra.AUDIO_CODEC_BANDWIDTH_KHZ";
 
+    /**
+     * Last known cell identity key to be used to fill geo location header in case of an emergency
+     * call. This entry will not be filled if call is not identified as an emergency call.
+     * {@link Connection}. Only provided to the {@link ConnectionService} for the purpose
+     * of placing an emergency call; will not be present in the {@link InCallService} layer.
+     * The {@link ConnectionService}'s implementation will be logged for fine location access
+     * when an outgoing call is placed in this case.
+     */
+    public static final String EXTRA_LAST_KNOWN_CELL_IDENTITY =
+            "android.telecom.extra.LAST_KNOWN_CELL_IDENTITY";
+
     /**
      * Boolean connection extra key used to indicate whether device to device communication is
      * available for the current call.

telephony/common/com/android/internal/telephony/TelephonyPermissions.java

@@ -564,6 +564,17 @@ public final class TelephonyPermissions {
         enforceCallingOrSelfCarrierPrivilege(context, subId, message);
     }
 
+    /**
+     * Check if the caller (or self, if not processing an IPC) has ACCESS_LAST_KNOWN_CELL_ID
+     * permission
+     *
+     * @return true if caller has ACCESS_LAST_KNOWN_CELL_ID permission else false.
+     */
+    public static boolean checkLastKnownCellIdAccessPermission(Context context) {
+        return context.checkCallingOrSelfPermission("android.permission.ACCESS_LAST_KNOWN_CELL_ID")
+                == PackageManager.PERMISSION_GRANTED;
+    }
+
     /**
      * Ensure the caller (or self, if not processing an IPC) has
      * {@link android.Manifest.permission#READ_PHONE_STATE} or carrier privileges.

telephony/java/android/telephony/TelephonyManager.java

@@ -15875,4 +15875,31 @@ public class TelephonyManager {
             ex.rethrowAsRuntimeException();
         }
     }
+
+    /**
+     * Get last known cell identity.
+     * Require {@link android.Manifest.permission#ACCESS_FINE_LOCATION} and
+     * com.android.phone.permission.ACCESS_LAST_KNOWN_CELL_ID, otherwise throws SecurityException.
+     * If there is current registered network this value will be same as the registered cell
+     * identity. If the device goes out of service the previous cell identity is cached and
+     * will be returned. If the cache age of the Cell identity is more than 24 hours
+     * it will be cleared and null will be returned.
+     * @return last known cell identity {@CellIdentity}.
+     * @hide
+     */
+    @RequiresPermission(allOf = {Manifest.permission.ACCESS_FINE_LOCATION,
+            "com.android.phone.permission.ACCESS_LAST_KNOWN_CELL_ID"})
+    public @Nullable CellIdentity getLastKnownCellIdentity() {
+        try {
+            ITelephony telephony = getITelephony();
+            if (telephony == null) {
+                throw new IllegalStateException("telephony service is null.");
+            }
+            return telephony.getLastKnownCellIdentity(getSubId(), getOpPackageName(),
+                    getAttributionTag());
+        } catch (RemoteException ex) {
+            ex.rethrowAsRuntimeException();
+        }
+        return null;
+    }
 }

telephony/java/com/android/internal/telephony/ITelephony.aidl

@@ -2509,4 +2509,13 @@ interface ITelephony {
      * Unregister an IMS connection state callback
      */
     void unregisterImsStateCallback(in IImsStateCallback cb);
+
+    /**
+     * return last known cell identity
+     * @param subId user preferred subId.
+     * @param callingPackage the name of the package making the call.
+     * @param callingFeatureId The feature in the package.
+     */
+    CellIdentity getLastKnownCellIdentity(int subId, String callingPackage,
+            String callingFeatureId);
 }