Merge "Add SystemApi utility for raw sockets." am: 91c81c13b6

am: 510d2f82ad

Change-Id: I2252fbfb4a793b33193037003823af68a56ae760

core/java/android/net/util/SocketUtils.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2015 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.util;
+
+import static android.system.OsConstants.SOL_SOCKET;
+import static android.system.OsConstants.SO_BINDTODEVICE;
+
+import android.annotation.SystemApi;
+import android.net.NetworkUtils;
+import android.system.ErrnoException;
+import android.system.NetlinkSocketAddress;
+import android.system.Os;
+import android.system.PacketSocketAddress;
+
+import java.io.FileDescriptor;
+import java.net.SocketAddress;
+
+/**
+ * Collection of utilities to interact with raw sockets.
+ * @hide
+ */
+@SystemApi
+public class SocketUtils {
+    /**
+     * Create a raw datagram socket that is bound to an interface.
+     *
+     * <p>Data sent through the socket will go directly to the underlying network, ignoring VPNs.
+     */
+    public static void bindSocketToInterface(FileDescriptor socket, String iface)
+            throws ErrnoException {
+        // SO_BINDTODEVICE actually takes a string. This works because the first member
+        // of struct ifreq is a NULL-terminated interface name.
+        // TODO: add a setsockoptString()
+        Os.setsockoptIfreq(socket, SOL_SOCKET, SO_BINDTODEVICE, iface);
+        NetworkUtils.protectFromVpn(socket);
+    }
+
+    /**
+     * Make a socket address to communicate with netlink.
+     */
+    public static SocketAddress makeNetlinkSocketAddress(int portId, int groupsMask) {
+        return new NetlinkSocketAddress(portId, groupsMask);
+    }
+
+    /**
+     * Make a socket address to bind to packet sockets.
+     */
+    public static SocketAddress makePacketSocketAddress(short protocol, int ifIndex) {
+        return new PacketSocketAddress(protocol, ifIndex);
+    }
+
+    /**
+     * Make a socket address to send raw packets.
+     */
+    public static SocketAddress makePacketSocketAddress(int ifIndex, byte[] hwAddr) {
+        return new PacketSocketAddress(ifIndex, hwAddr);
+    }
+
+    private SocketUtils() {}
+}