Add keepalive related methods and fields to system APIs

Add KeepalivePacketData to system API for mainline support.
Also, remove InvalidPacketException class from SocketKeepalive
and create a new InvalidPacketException class in android.net

Bug: 139268426
Bug: 135998869
Bug: 138306002
Test: atest FrameworksNetTests
      atest NetworkStackTests
      atest FrameworksTelephonyTests
      ./frameworks/opt/net/wifi/tests/wifitests/runtests.sh
      atest android.net.cts
      atest android.net.wifi.cts
      atest android.telephony.cts

Change-Id: I2d982e8abb5cb6b4c74a20483550b18cf814320d
diff --git a/api/system-current.txt b/api/system-current.txt
index fe9c0d1..4b4d0e1 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -4432,6 +4432,14 @@
     method public void onUpstreamChanged(@Nullable android.net.Network);
   }
 
+  public class InvalidPacketException extends java.lang.Exception {
+    ctor public InvalidPacketException(int);
+    field public static final int ERROR_INVALID_IP_ADDRESS = -21; // 0xffffffeb
+    field public static final int ERROR_INVALID_LENGTH = -23; // 0xffffffe9
+    field public static final int ERROR_INVALID_PORT = -22; // 0xffffffea
+    field public final int error;
+  }
+
   public final class IpConfiguration implements android.os.Parcelable {
     ctor public IpConfiguration();
     ctor public IpConfiguration(@NonNull android.net.IpConfiguration);
@@ -4482,6 +4490,15 @@
     method @NonNull @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) public android.net.IpSecTransform buildTunnelModeTransform(@NonNull java.net.InetAddress, @NonNull android.net.IpSecManager.SecurityParameterIndex) throws java.io.IOException, android.net.IpSecManager.ResourceUnavailableException, android.net.IpSecManager.SpiUnavailableException;
   }
 
+  public class KeepalivePacketData {
+    ctor protected KeepalivePacketData(@NonNull java.net.InetAddress, int, @NonNull java.net.InetAddress, int, @NonNull byte[]) throws android.net.InvalidPacketException;
+    method @NonNull public byte[] getPacket();
+    field @NonNull public final java.net.InetAddress dstAddress;
+    field public final int dstPort;
+    field @NonNull public final java.net.InetAddress srcAddress;
+    field public final int srcPort;
+  }
+
   public class LinkAddress implements android.os.Parcelable {
     ctor public LinkAddress(@NonNull java.net.InetAddress, @IntRange(from=0, to=128) int, int, int);
     ctor public LinkAddress(@NonNull java.net.InetAddress, @IntRange(from=0, to=128) int);
diff --git a/core/java/android/net/InvalidPacketException.java b/core/java/android/net/InvalidPacketException.java
new file mode 100644
index 0000000..909998d
--- /dev/null
+++ b/core/java/android/net/InvalidPacketException.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.IntDef;
+import android.annotation.SystemApi;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Thrown when a packet is invalid.
+ * @hide
+ */
+@SystemApi
+public class InvalidPacketException extends Exception {
+    public final int error;
+
+    // Must match SocketKeepalive#ERROR_INVALID_IP_ADDRESS.
+    /** Invalid IP address. */
+    public static final int ERROR_INVALID_IP_ADDRESS = -21;
+
+    // Must match SocketKeepalive#ERROR_INVALID_PORT.
+    /** Invalid port number. */
+    public static final int ERROR_INVALID_PORT = -22;
+
+    // Must match SocketKeepalive#ERROR_INVALID_LENGTH.
+    /** Invalid packet length. */
+    public static final int ERROR_INVALID_LENGTH = -23;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "ERROR_" }, value = {
+        ERROR_INVALID_IP_ADDRESS,
+        ERROR_INVALID_PORT,
+        ERROR_INVALID_LENGTH
+    })
+    public @interface ErrorCode {}
+
+    /**
+     * This packet is invalid.
+     * See the error code for details.
+     */
+    public InvalidPacketException(@ErrorCode final int error) {
+        this.error = error;
+    }
+}
diff --git a/core/java/android/net/KeepalivePacketData.java b/core/java/android/net/KeepalivePacketData.java
index 9b8b732..2b8b7e6 100644
--- a/core/java/android/net/KeepalivePacketData.java
+++ b/core/java/android/net/KeepalivePacketData.java
@@ -16,13 +16,13 @@
 
 package android.net;
 
-import static android.net.SocketKeepalive.ERROR_INVALID_IP_ADDRESS;
-import static android.net.SocketKeepalive.ERROR_INVALID_PORT;
+import static android.net.InvalidPacketException.ERROR_INVALID_IP_ADDRESS;
+import static android.net.InvalidPacketException.ERROR_INVALID_PORT;
 
-import android.net.SocketKeepalive.InvalidPacketException;
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
 import android.net.util.IpUtils;
 import android.os.Parcel;
-import android.os.Parcelable;
 import android.util.Log;
 
 import java.net.InetAddress;
@@ -33,13 +33,16 @@
  *
  * @hide
  */
-public class KeepalivePacketData implements Parcelable {
+@SystemApi
+public class KeepalivePacketData {
     private static final String TAG = "KeepalivePacketData";
 
     /** Source IP address */
+    @NonNull
     public final InetAddress srcAddress;
 
     /** Destination IP address */
+    @NonNull
     public final InetAddress dstAddress;
 
     /** Source port */
@@ -51,13 +54,14 @@
     /** Packet data. A raw byte string of packet data, not including the link-layer header. */
     private final byte[] mPacket;
 
-    protected static final int IPV4_HEADER_LENGTH = 20;
-    protected static final int UDP_HEADER_LENGTH = 8;
-
     // This should only be constructed via static factory methods, such as
-    // nattKeepalivePacket
-    protected KeepalivePacketData(InetAddress srcAddress, int srcPort,
-            InetAddress dstAddress, int dstPort, byte[] data) throws InvalidPacketException {
+    // nattKeepalivePacket.
+    /**
+     * A holding class for data necessary to build a keepalive packet.
+     */
+    protected KeepalivePacketData(@NonNull InetAddress srcAddress, int srcPort,
+            @NonNull InetAddress dstAddress, int dstPort,
+                    @NonNull byte[] data) throws InvalidPacketException {
         this.srcAddress = srcAddress;
         this.dstAddress = dstAddress;
         this.srcPort = srcPort;
@@ -78,16 +82,12 @@
         }
     }
 
+    @NonNull
     public byte[] getPacket() {
         return mPacket.clone();
     }
 
-    /* Parcelable Implementation */
-    public int describeContents() {
-        return 0;
-    }
-
-    /** Write to parcel */
+    /** @hide */
     public void writeToParcel(Parcel out, int flags) {
         out.writeString(srcAddress.getHostAddress());
         out.writeString(dstAddress.getHostAddress());
@@ -96,6 +96,7 @@
         out.writeByteArray(mPacket);
     }
 
+    /** @hide */
     protected KeepalivePacketData(Parcel in) {
         srcAddress = NetworkUtils.numericToInetAddress(in.readString());
         dstAddress = NetworkUtils.numericToInetAddress(in.readString());
@@ -103,17 +104,4 @@
         dstPort = in.readInt();
         mPacket = in.createByteArray();
     }
-
-    /** Parcelable Creator */
-    public static final @android.annotation.NonNull Parcelable.Creator<KeepalivePacketData> CREATOR =
-            new Parcelable.Creator<KeepalivePacketData>() {
-                public KeepalivePacketData createFromParcel(Parcel in) {
-                    return new KeepalivePacketData(in);
-                }
-
-                public KeepalivePacketData[] newArray(int size) {
-                    return new KeepalivePacketData[size];
-                }
-            };
-
 }
diff --git a/core/java/android/net/NattKeepalivePacketData.java b/core/java/android/net/NattKeepalivePacketData.java
index a77c244..3fb52f1 100644
--- a/core/java/android/net/NattKeepalivePacketData.java
+++ b/core/java/android/net/NattKeepalivePacketData.java
@@ -19,7 +19,6 @@
 import static android.net.SocketKeepalive.ERROR_INVALID_IP_ADDRESS;
 import static android.net.SocketKeepalive.ERROR_INVALID_PORT;
 
-import android.net.SocketKeepalive.InvalidPacketException;
 import android.net.util.IpUtils;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -32,6 +31,9 @@
 
 /** @hide */
 public final class NattKeepalivePacketData extends KeepalivePacketData implements Parcelable {
+    private static final int IPV4_HEADER_LENGTH = 20;
+    private static final int UDP_HEADER_LENGTH = 8;
+
     // This should only be constructed via static factory methods, such as
     // nattKeepalivePacket
     private NattKeepalivePacketData(InetAddress srcAddress, int srcPort,
diff --git a/core/java/android/net/SocketKeepalive.java b/core/java/android/net/SocketKeepalive.java
index ec73866..fb224fb 100644
--- a/core/java/android/net/SocketKeepalive.java
+++ b/core/java/android/net/SocketKeepalive.java
@@ -147,17 +147,6 @@
         }
     }
 
-    /**
-     * This packet is invalid.
-     * See the error code for details.
-     * @hide
-     */
-    public static class InvalidPacketException extends ErrorCodeException {
-        public InvalidPacketException(final int error) {
-            super(error);
-        }
-    }
-
     @NonNull final IConnectivityManager mService;
     @NonNull final Network mNetwork;
     @NonNull final ParcelFileDescriptor mPfd;
diff --git a/services/core/java/com/android/server/connectivity/KeepaliveTracker.java b/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
index 9bae902..af8a366 100644
--- a/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
+++ b/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
@@ -39,11 +39,11 @@
 import android.annotation.Nullable;
 import android.content.Context;
 import android.net.ISocketKeepaliveCallback;
+import android.net.InvalidPacketException;
 import android.net.KeepalivePacketData;
 import android.net.NattKeepalivePacketData;
 import android.net.NetworkAgent;
 import android.net.NetworkUtils;
-import android.net.SocketKeepalive.InvalidPacketException;
 import android.net.SocketKeepalive.InvalidSocketException;
 import android.net.TcpKeepalivePacketData;
 import android.net.util.IpUtils;
@@ -657,7 +657,10 @@
         final TcpKeepalivePacketData packet;
         try {
             packet = TcpKeepaliveController.getTcpKeepalivePacket(fd);
-        } catch (InvalidPacketException | InvalidSocketException e) {
+        } catch (InvalidSocketException e) {
+            notifyErrorCallback(cb, e.error);
+            return;
+        } catch (InvalidPacketException e) {
             notifyErrorCallback(cb, e.error);
             return;
         }
diff --git a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
index e570ef1e..1129899 100644
--- a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
+++ b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
@@ -30,8 +30,8 @@
 import static android.system.OsConstants.TIOCOUTQ;
 
 import android.annotation.NonNull;
+import android.net.InvalidPacketException;
 import android.net.NetworkUtils;
-import android.net.SocketKeepalive.InvalidPacketException;
 import android.net.SocketKeepalive.InvalidSocketException;
 import android.net.TcpKeepalivePacketData;
 import android.net.TcpKeepalivePacketDataParcelable;
diff --git a/services/net/java/android/net/TcpKeepalivePacketData.java b/services/net/java/android/net/TcpKeepalivePacketData.java
index 7f2f499..aad75ae 100644
--- a/services/net/java/android/net/TcpKeepalivePacketData.java
+++ b/services/net/java/android/net/TcpKeepalivePacketData.java
@@ -19,7 +19,6 @@
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.net.SocketKeepalive.InvalidPacketException;
 import android.net.util.IpUtils;
 import android.os.Parcel;
 import android.os.Parcelable;
diff --git a/tests/net/java/android/net/TcpKeepalivePacketDataTest.java b/tests/net/java/android/net/TcpKeepalivePacketDataTest.java
index 5cb0d7e..e632aaf 100644
--- a/tests/net/java/android/net/TcpKeepalivePacketDataTest.java
+++ b/tests/net/java/android/net/TcpKeepalivePacketDataTest.java
@@ -22,8 +22,6 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
 
-import android.net.SocketKeepalive.InvalidPacketException;
-
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;