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/*
* Copyright (C) 2010 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.dhcp;
import java.net.Inet4Address;
import java.nio.ByteBuffer;
/**
* This class implements the DHCP-ACK packet.
*/
public class DhcpAckPacket extends DhcpPacket {
/**
* The address of the server which sent this packet.
*/
private final Inet4Address mSrcIp;
DhcpAckPacket(int transId, short secs, boolean broadcast, Inet4Address serverAddress,
Inet4Address relayIp, Inet4Address clientIp, Inet4Address yourIp, byte[] clientMac,
boolean rapidCommit) {
super(transId, secs, clientIp, yourIp, serverAddress, relayIp, clientMac, broadcast);
mBroadcast = broadcast;
mSrcIp = serverAddress;
mRapidCommit = rapidCommit;
}
public String toString() {
String s = super.toString();
String dnsServers = " DNS servers: ";
for (Inet4Address dnsServer: mDnsServers) {
dnsServers += dnsServer.toString() + " ";
}
return s + " ACK: your new IP " + mYourIp
+ ", netmask " + mSubnetMask
+ ", gateways " + mGateways + dnsServers
+ ", lease time " + mLeaseTime
+ (mIpv6OnlyWaitTime != null ? ", V6ONLY_WAIT " + mIpv6OnlyWaitTime : "");
}
/**
* Fills in a packet with the requested ACK parameters.
*/
public ByteBuffer buildPacket(int encap, short destUdp, short srcUdp) {
ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH);
Inet4Address destIp = mBroadcast ? INADDR_BROADCAST : mYourIp;
Inet4Address srcIp = mBroadcast ? INADDR_ANY : mSrcIp;
fillInPacket(encap, destIp, srcIp, destUdp, srcUdp, result,
DHCP_BOOTREPLY, mBroadcast);
result.flip();
return result;
}
/**
* Adds the optional parameters to the client-generated ACK packet.
*/
void finishPacket(ByteBuffer buffer) {
addTlv(buffer, DHCP_MESSAGE_TYPE, DHCP_MESSAGE_TYPE_ACK);
addTlv(buffer, DHCP_SERVER_IDENTIFIER, mServerIdentifier);
addCommonServerTlvs(buffer);
if (mRapidCommit) {
addTlv(buffer, DHCP_RAPID_COMMIT);
}
addTlvEnd(buffer);
}
/**
* Un-boxes an Integer, returning 0 if a null reference is supplied.
*/
private static final int getInt(Integer v) {
if (v == null) {
return 0;
} else {
return v.intValue();
}
}
}
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