Merge "Allow VcnTransportInfo to be parcelled"

core/java/android/net/vcn/VcnTransportInfo.java

@@ -16,14 +16,23 @@
 
 package android.net.vcn;
 
+import static android.net.NetworkCapabilities.REDACT_ALL;
+import static android.net.NetworkCapabilities.REDACT_FOR_NETWORK_SETTINGS;
+import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
+
+import static com.android.internal.annotations.VisibleForTesting.Visibility.PRIVATE;
+
 import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.net.NetworkCapabilities;
 import android.net.TransportInfo;
 import android.net.wifi.WifiInfo;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.telephony.SubscriptionManager;
 
+import com.android.internal.annotations.VisibleForTesting;
+
 import java.util.Objects;
 
 /**
@@ -37,28 +46,41 @@ import java.util.Objects;
  * SubscriptionManager#INVALID_SUBSCRIPTION_ID}. If the underlying Network is Cellular, the WifiInfo
  * will be {@code null}.
  *
+ * <p>Receipt of a VcnTransportInfo requires the NETWORK_SETTINGS permission; else the entire
+ * VcnTransportInfo instance will be redacted.
+ *
  * @hide
  */
 public class VcnTransportInfo implements TransportInfo, Parcelable {
     @Nullable private final WifiInfo mWifiInfo;
     private final int mSubId;
 
+    /**
+     * The redaction scheme to use when parcelling.
+     *
+     * <p>The TransportInfo/NetworkCapabilities redaction mechanisms rely on redaction being
+     * performed at parcelling time. This means that the redaction scheme must be stored for later
+     * use.
+     *
+     * <p>Since the redaction scheme itself is not parcelled, this field is listed as a transient.
+     *
+     * <p>Defaults to REDACT_ALL when constructed using public constructors, or creating from
+     * parcels.
+     */
+    private final transient long mRedactions;
+
     public VcnTransportInfo(@NonNull WifiInfo wifiInfo) {
-        this(wifiInfo, SubscriptionManager.INVALID_SUBSCRIPTION_ID);
+        this(wifiInfo, INVALID_SUBSCRIPTION_ID, REDACT_ALL);
     }
 
     public VcnTransportInfo(int subId) {
-        this(null /* wifiInfo */, subId);
+        this(null /* wifiInfo */, subId, REDACT_ALL);
     }
 
-    private VcnTransportInfo(@Nullable WifiInfo wifiInfo, int subId) {
+    private VcnTransportInfo(@Nullable WifiInfo wifiInfo, int subId, long redactions) {
-        if (wifiInfo == null && subId == SubscriptionManager.INVALID_SUBSCRIPTION_ID) {
-            throw new IllegalArgumentException(
-                    "VcnTransportInfo requires either non-null WifiInfo or valid subId");
-        }
-
         mWifiInfo = wifiInfo;
         mSubId = subId;
+        mRedactions = redactions;
     }
 
     /**
@@ -86,8 +108,19 @@ public class VcnTransportInfo implements TransportInfo, Parcelable {
         return mSubId;
     }
 
+    /**
+     * Gets the redaction scheme
+     *
+     * @hide
+     */
+    @VisibleForTesting(visibility = PRIVATE)
+    public long getRedaction() {
+        return mRedactions;
+    }
+
     @Override
     public int hashCode() {
+        // mRedactions not hashed, as it is a transient, for control of parcelling
         return Objects.hash(mWifiInfo, mSubId);
     }
 
@@ -96,6 +129,7 @@ public class VcnTransportInfo implements TransportInfo, Parcelable {
         if (!(o instanceof VcnTransportInfo)) return false;
         final VcnTransportInfo that = (VcnTransportInfo) o;
 
+        // mRedactions not compared, as it is a transient, for control of parcelling
         return Objects.equals(mWifiInfo, that.mWifiInfo) && mSubId == that.mSubId;
     }
 
@@ -105,17 +139,59 @@ public class VcnTransportInfo implements TransportInfo, Parcelable {
         return 0;
     }
 
+    @Override
+    @NonNull
+    public TransportInfo makeCopy(long redactions) {
+        return new VcnTransportInfo(
+                mWifiInfo == null ? null : mWifiInfo.makeCopy(redactions), mSubId, redactions);
+    }
+
+    @Override
+    public long getApplicableRedactions() {
+        long redactions = REDACT_FOR_NETWORK_SETTINGS;
+
+        // Add additional wifi redactions if necessary
+        if (mWifiInfo != null) {
+            redactions |= mWifiInfo.getApplicableRedactions();
+        }
+
+        return redactions;
+    }
+
+    private boolean shouldParcelNetworkSettingsFields() {
+        return (mRedactions & NetworkCapabilities.REDACT_FOR_NETWORK_SETTINGS) == 0;
+    }
+
     /** {@inheritDoc} */
     @Override
-    public void writeToParcel(@NonNull Parcel dest, int flags) {}
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(shouldParcelNetworkSettingsFields() ? mSubId : INVALID_SUBSCRIPTION_ID);
+        dest.writeParcelable(
+                shouldParcelNetworkSettingsFields() ? (Parcelable) mWifiInfo : null, flags);
+    }
+
+    @Override
+    public String toString() {
+        return "VcnTransportInfo { mWifiInfo = " + mWifiInfo + ", mSubId = " + mSubId + " }";
+    }
 
     /** Implement the Parcelable interface */
     public static final @NonNull Creator<VcnTransportInfo> CREATOR =
             new Creator<VcnTransportInfo>() {
                 public VcnTransportInfo createFromParcel(Parcel in) {
-                    // return null instead of a default VcnTransportInfo to avoid leaking
+                    final int subId = in.readInt();
-                    // information about this being a VCN Network (instead of macro cellular, etc)
+                    final WifiInfo wifiInfo = in.readParcelable(null);
-                    return null;
+
+                    // If all fields are their null values, return null TransportInfo to avoid
+                    // leaking information about this being a VCN Network (instead of macro
+                    // cellular, etc)
+                    if (wifiInfo == null && subId == INVALID_SUBSCRIPTION_ID) {
+                        return null;
+                    }
+
+                    // Prevent further forwarding by redacting everything in future parcels from
+                    // this VcnTransportInfo
+                    return new VcnTransportInfo(wifiInfo, subId, REDACT_ALL);
                 }
 
                 public VcnTransportInfo[] newArray(int size) {

tests/vcn/java/android/net/vcn/VcnTransportInfoTest.java

@@ -16,6 +16,8 @@
 
 package android.net.vcn;
 
+import static android.net.NetworkCapabilities.REDACT_ALL;
+import static android.net.NetworkCapabilities.REDACT_FOR_NETWORK_SETTINGS;
 import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
 import static org.junit.Assert.assertEquals;
@@ -36,6 +38,12 @@ public class VcnTransportInfoTest {
     private static final VcnTransportInfo CELL_UNDERLYING_INFO = new VcnTransportInfo(SUB_ID);
     private static final VcnTransportInfo WIFI_UNDERLYING_INFO = new VcnTransportInfo(WIFI_INFO);
 
+    @Test
+    public void testRedactionDefaults() {
+        assertEquals(REDACT_ALL, CELL_UNDERLYING_INFO.getRedaction());
+        assertEquals(REDACT_ALL, WIFI_UNDERLYING_INFO.getRedaction());
+    }
+
     @Test
     public void testGetWifiInfo() {
         assertEquals(WIFI_INFO, WIFI_UNDERLYING_INFO.getWifiInfo());
@@ -50,6 +58,18 @@ public class VcnTransportInfoTest {
         assertEquals(INVALID_SUBSCRIPTION_ID, WIFI_UNDERLYING_INFO.getSubId());
     }
 
+    @Test
+    public void testMakeCopySetsRedactions() {
+        assertEquals(
+                REDACT_FOR_NETWORK_SETTINGS,
+                ((VcnTransportInfo) CELL_UNDERLYING_INFO.makeCopy(REDACT_FOR_NETWORK_SETTINGS))
+                        .getRedaction());
+        assertEquals(
+                REDACT_FOR_NETWORK_SETTINGS,
+                ((VcnTransportInfo) WIFI_UNDERLYING_INFO.makeCopy(REDACT_FOR_NETWORK_SETTINGS))
+                        .getRedaction());
+    }
+
     @Test
     public void testEquals() {
         assertEquals(CELL_UNDERLYING_INFO, CELL_UNDERLYING_INFO);
@@ -64,8 +84,29 @@ public class VcnTransportInfoTest {
     }
 
     private void verifyParcelingIsNull(VcnTransportInfo vcnTransportInfo) {
+        // Verify redacted by default
         Parcel parcel = Parcel.obtain();
         vcnTransportInfo.writeToParcel(parcel, 0 /* flags */);
+        parcel.setDataPosition(0);
+
         assertNull(VcnTransportInfo.CREATOR.createFromParcel(parcel));
     }
+
+    @Test
+    public void testParcelUnparcelNotRedactedForSysUi() {
+        verifyParcelingForSysUi(CELL_UNDERLYING_INFO);
+        verifyParcelingForSysUi(WIFI_UNDERLYING_INFO);
+    }
+
+    private void verifyParcelingForSysUi(VcnTransportInfo vcnTransportInfo) {
+        // Allow fully unredacted; SysUI will have all the relevant permissions.
+        final VcnTransportInfo unRedacted = (VcnTransportInfo) vcnTransportInfo.makeCopy(0);
+        final Parcel parcel = Parcel.obtain();
+        unRedacted.writeToParcel(parcel, 0 /* flags */);
+        parcel.setDataPosition(0);
+
+        final VcnTransportInfo unparceled = VcnTransportInfo.CREATOR.createFromParcel(parcel);
+        assertEquals(vcnTransportInfo, unparceled);
+        assertEquals(REDACT_ALL, unparceled.getRedaction());
+    }
 }