NetworkUtils.java revision 0900f3657664d9046e6723825fd32b244eef2b6c 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.net;
18
19import java.net.InetAddress;
20import java.net.UnknownHostException;
21
22/**
23 * Native methods for managing network interfaces.
24 *
25 * {@hide}
26 */
27public class NetworkUtils {
28    /** Bring the named network interface up. */
29    public native static int enableInterface(String interfaceName);
30
31    /** Bring the named network interface down. */
32    public native static int disableInterface(String interfaceName);
33
34    /** Add a route to the specified host via the named interface. */
35    public native static int addHostRoute(String interfaceName, int hostaddr);
36
37    /** Add a default route for the named interface. */
38    public native static int setDefaultRoute(String interfaceName, int gwayAddr);
39
40    /** Return the gateway address for the default route for the named interface. */
41    public native static int getDefaultRoute(String interfaceName);
42
43    /** Remove host routes that uses the named interface. */
44    public native static int removeHostRoutes(String interfaceName);
45
46    /** Remove the default route for the named interface. */
47    public native static int removeDefaultRoute(String interfaceName);
48
49    /** Reset any sockets that are connected via the named interface. */
50    public native static int resetConnections(String interfaceName);
51
52    /**
53     * Start the DHCP client daemon, in order to have it request addresses
54     * for the named interface, and then configure the interface with those
55     * addresses. This call blocks until it obtains a result (either success
56     * or failure) from the daemon.
57     * @param interfaceName the name of the interface to configure
58     * @param ipInfo if the request succeeds, this object is filled in with
59     * the IP address information.
60     * @return {@code true} for success, {@code false} for failure
61     */
62    public native static boolean runDhcp(String interfaceName, DhcpInfo ipInfo);
63
64    /**
65     * Shut down the DHCP client daemon.
66     * @param interfaceName the name of the interface for which the daemon
67     * should be stopped
68     * @return {@code true} for success, {@code false} for failure
69     */
70    public native static boolean stopDhcp(String interfaceName);
71
72    /**
73     * Release the current DHCP lease.
74     * @param interfaceName the name of the interface for which the lease should
75     * be released
76     * @return {@code true} for success, {@code false} for failure
77     */
78    public native static boolean releaseDhcpLease(String interfaceName);
79
80    /**
81     * Return the last DHCP-related error message that was recorded.
82     * <p/>NOTE: This string is not localized, but currently it is only
83     * used in logging.
84     * @return the most recent error message, if any
85     */
86    public native static String getDhcpError();
87
88    /**
89     * When static IP configuration has been specified, configure the network
90     * interface according to the values supplied.
91     * @param interfaceName the name of the interface to configure
92     * @param ipInfo the IP address, default gateway, and DNS server addresses
93     * with which to configure the interface.
94     * @return {@code true} for success, {@code false} for failure
95     */
96    public static boolean configureInterface(String interfaceName, DhcpInfo ipInfo) {
97        return configureNative(interfaceName,
98            ipInfo.ipAddress,
99            ipInfo.netmask,
100            ipInfo.gateway,
101            ipInfo.dns1,
102            ipInfo.dns2);
103    }
104
105    private native static boolean configureNative(
106        String interfaceName, int ipAddress, int netmask, int gateway, int dns1, int dns2);
107
108    /**
109     * Look up a host name and return the result as an int. Works if the argument
110     * is an IP address in dot notation. Obviously, this can only be used for IPv4
111     * addresses.
112     * @param hostname the name of the host (or the IP address)
113     * @return the IP address as an {@code int} in network byte order
114     */
115    public static int lookupHost(String hostname) {
116        InetAddress inetAddress;
117        try {
118            inetAddress = InetAddress.getByName(hostname);
119        } catch (UnknownHostException e) {
120            return -1;
121        }
122        byte[] addrBytes;
123        int addr;
124        addrBytes = inetAddress.getAddress();
125        addr = ((addrBytes[3] & 0xff) << 24)
126                | ((addrBytes[2] & 0xff) << 16)
127                | ((addrBytes[1] & 0xff) << 8)
128                |  (addrBytes[0] & 0xff);
129        return addr;
130    }
131}
132