Move module sources to packages/Connectivity

Files that are planned to be part of the connectivity module are grouped
in packages/Connectivity, so they can be built separately and moved in
one operation with their history into packages/modules/Connectivity.

This places the files in the existing framework-connectivity-sources
filegroup instead of the current framework-core-sources filegroup. Both
are used the same way in framework-non-updatable-sources.

Bug: 171540887
Test: m
Change-Id: I62d9d91574ace6f5c4624035d190260c3126b91e
diff --git a/framework/src/android/net/NattKeepalivePacketData.java b/framework/src/android/net/NattKeepalivePacketData.java
new file mode 100644
index 0000000..c4f8fc2
--- /dev/null
+++ b/framework/src/android/net/NattKeepalivePacketData.java
@@ -0,0 +1,144 @@
+/*
+ * 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 static android.net.InvalidPacketException.ERROR_INVALID_IP_ADDRESS;
+import static android.net.InvalidPacketException.ERROR_INVALID_PORT;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.system.OsConstants;
+
+import com.android.net.module.util.IpUtils;
+
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Objects;
+
+/** @hide */
+@SystemApi
+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
+    public NattKeepalivePacketData(@NonNull InetAddress srcAddress, int srcPort,
+            @NonNull InetAddress dstAddress, int dstPort, @NonNull byte[] data) throws
+            InvalidPacketException {
+        super(srcAddress, srcPort, dstAddress, dstPort, data);
+    }
+
+    /**
+     * Factory method to create Nat-T keepalive packet structure.
+     * @hide
+     */
+    public static NattKeepalivePacketData nattKeepalivePacket(
+            InetAddress srcAddress, int srcPort, InetAddress dstAddress, int dstPort)
+            throws InvalidPacketException {
+
+        if (!(srcAddress instanceof Inet4Address) || !(dstAddress instanceof Inet4Address)) {
+            throw new InvalidPacketException(ERROR_INVALID_IP_ADDRESS);
+        }
+
+        if (dstPort != NattSocketKeepalive.NATT_PORT) {
+            throw new InvalidPacketException(ERROR_INVALID_PORT);
+        }
+
+        int length = IPV4_HEADER_LENGTH + UDP_HEADER_LENGTH + 1;
+        ByteBuffer buf = ByteBuffer.allocate(length);
+        buf.order(ByteOrder.BIG_ENDIAN);
+        buf.putShort((short) 0x4500);             // IP version and TOS
+        buf.putShort((short) length);
+        buf.putInt(0);                            // ID, flags, offset
+        buf.put((byte) 64);                       // TTL
+        buf.put((byte) OsConstants.IPPROTO_UDP);
+        int ipChecksumOffset = buf.position();
+        buf.putShort((short) 0);                  // IP checksum
+        buf.put(srcAddress.getAddress());
+        buf.put(dstAddress.getAddress());
+        buf.putShort((short) srcPort);
+        buf.putShort((short) dstPort);
+        buf.putShort((short) (length - 20));      // UDP length
+        int udpChecksumOffset = buf.position();
+        buf.putShort((short) 0);                  // UDP checksum
+        buf.put((byte) 0xff);                     // NAT-T keepalive
+        buf.putShort(ipChecksumOffset, IpUtils.ipChecksum(buf, 0));
+        buf.putShort(udpChecksumOffset, IpUtils.udpChecksum(buf, 0, IPV4_HEADER_LENGTH));
+
+        return new NattKeepalivePacketData(srcAddress, srcPort, dstAddress, dstPort, buf.array());
+    }
+
+    /** Parcelable Implementation */
+    public int describeContents() {
+        return 0;
+    }
+
+    /** Write to parcel */
+    public void writeToParcel(@NonNull Parcel out, int flags) {
+        out.writeString(getSrcAddress().getHostAddress());
+        out.writeString(getDstAddress().getHostAddress());
+        out.writeInt(getSrcPort());
+        out.writeInt(getDstPort());
+    }
+
+    /** Parcelable Creator */
+    public static final @NonNull Parcelable.Creator<NattKeepalivePacketData> CREATOR =
+            new Parcelable.Creator<NattKeepalivePacketData>() {
+                public NattKeepalivePacketData createFromParcel(Parcel in) {
+                    final InetAddress srcAddress =
+                            InetAddresses.parseNumericAddress(in.readString());
+                    final InetAddress dstAddress =
+                            InetAddresses.parseNumericAddress(in.readString());
+                    final int srcPort = in.readInt();
+                    final int dstPort = in.readInt();
+                    try {
+                        return NattKeepalivePacketData.nattKeepalivePacket(srcAddress, srcPort,
+                                    dstAddress, dstPort);
+                    } catch (InvalidPacketException e) {
+                        throw new IllegalArgumentException(
+                                "Invalid NAT-T keepalive data: " + e.getError());
+                    }
+                }
+
+                public NattKeepalivePacketData[] newArray(int size) {
+                    return new NattKeepalivePacketData[size];
+                }
+            };
+
+    @Override
+    public boolean equals(@Nullable final Object o) {
+        if (!(o instanceof NattKeepalivePacketData)) return false;
+        final NattKeepalivePacketData other = (NattKeepalivePacketData) o;
+        final InetAddress srcAddress = getSrcAddress();
+        final InetAddress dstAddress = getDstAddress();
+        return srcAddress.equals(other.getSrcAddress())
+            && dstAddress.equals(other.getDstAddress())
+            && getSrcPort() == other.getSrcPort()
+            && getDstPort() == other.getDstPort();
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getSrcAddress(), getDstAddress(), getSrcPort(), getDstPort());
+    }
+}