Support QosCallback for UDP socket -Filter

Add matchProtocol() to QosFilter.
Add remoteAddress check to validate().
Add exception EX_TYPE_FILTER_SOCKET_REMOTE_ADDRESS_CHANGED
Don't send ParcelFileDescriptor to QosProvider for security reason

Bug: 203146631
Test: atest & verified on LTE test equipment
Change-Id: I7102ae9ba7cb9e1cc8d06b252aad4dad75860f3e
diff --git a/framework/src/android/net/QosSocketInfo.java b/framework/src/android/net/QosSocketInfo.java
index 39c2f33..49ac22b 100644
--- a/framework/src/android/net/QosSocketInfo.java
+++ b/framework/src/android/net/QosSocketInfo.java
@@ -165,25 +165,28 @@
     /* Parcelable methods */
     private QosSocketInfo(final Parcel in) {
         mNetwork = Objects.requireNonNull(Network.CREATOR.createFromParcel(in));
-        mParcelFileDescriptor = ParcelFileDescriptor.CREATOR.createFromParcel(in);
+        final boolean withFd = in.readBoolean();
+        if (withFd) {
+            mParcelFileDescriptor = ParcelFileDescriptor.CREATOR.createFromParcel(in);
+        } else {
+            mParcelFileDescriptor = null;
+        }
 
-        final int localAddressLength = in.readInt();
-        mLocalSocketAddress = readSocketAddress(in, localAddressLength);
-
-        final int remoteAddressLength = in.readInt();
-        mRemoteSocketAddress = remoteAddressLength == 0 ? null
-                : readSocketAddress(in, remoteAddressLength);
+        mLocalSocketAddress = readSocketAddress(in);
+        mRemoteSocketAddress = readSocketAddress(in);
 
         mSocketType = in.readInt();
     }
 
-    private @NonNull InetSocketAddress readSocketAddress(final Parcel in, final int addressLength) {
-        final byte[] address = new byte[addressLength];
-        in.readByteArray(address);
+    private InetSocketAddress readSocketAddress(final Parcel in) {
+        final byte[] addrBytes = in.createByteArray();
+        if (addrBytes == null) {
+            return null;
+        }
         final int port = in.readInt();
 
         try {
-            return new InetSocketAddress(InetAddress.getByAddress(address), port);
+            return new InetSocketAddress(InetAddress.getByAddress(addrBytes), port);
         } catch (final UnknownHostException e) {
             /* This can never happen. UnknownHostException will never be thrown
                since the address provided is numeric and non-null. */
@@ -198,20 +201,35 @@
 
     @Override
     public void writeToParcel(@NonNull final Parcel dest, final int flags) {
-        mNetwork.writeToParcel(dest, 0);
-        mParcelFileDescriptor.writeToParcel(dest, 0);
+        writeToParcelInternal(dest, flags, /*includeFd=*/ true);
+    }
 
-        final byte[] localAddress = mLocalSocketAddress.getAddress().getAddress();
-        dest.writeInt(localAddress.length);
-        dest.writeByteArray(localAddress);
+    /**
+     * Used when sending QosSocketInfo to telephony, which does not need access to the socket FD.
+     * @hide
+     */
+    public void writeToParcelWithoutFd(@NonNull final Parcel dest, final int flags) {
+        writeToParcelInternal(dest, flags, /*includeFd=*/ false);
+    }
+
+    private void writeToParcelInternal(
+            @NonNull final Parcel dest, final int flags, boolean includeFd) {
+        mNetwork.writeToParcel(dest, 0);
+
+        if (includeFd) {
+            dest.writeBoolean(true);
+            mParcelFileDescriptor.writeToParcel(dest, 0);
+        } else {
+            dest.writeBoolean(false);
+        }
+
+        dest.writeByteArray(mLocalSocketAddress.getAddress().getAddress());
         dest.writeInt(mLocalSocketAddress.getPort());
 
         if (mRemoteSocketAddress == null) {
-            dest.writeInt(0);
+            dest.writeByteArray(null);
         } else {
-            final byte[] remoteAddress = mRemoteSocketAddress.getAddress().getAddress();
-            dest.writeInt(remoteAddress.length);
-            dest.writeByteArray(remoteAddress);
+            dest.writeByteArray(mRemoteSocketAddress.getAddress().getAddress());
             dest.writeInt(mRemoteSocketAddress.getPort());
         }
         dest.writeInt(mSocketType);