| /* |
| * 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-OFFER packet. |
| */ |
| class DhcpOfferPacket extends DhcpPacket { |
| /** |
| * The IP address of the server which sent this packet. |
| */ |
| private final Inet4Address mSrcIp; |
| |
| /** |
| * Generates a OFFER packet with the specified parameters. |
| */ |
| DhcpOfferPacket(int transId, short secs, boolean broadcast, Inet4Address serverAddress, |
| Inet4Address relayIp, Inet4Address clientIp, Inet4Address yourIp, byte[] clientMac) { |
| super(transId, secs, clientIp, yourIp, serverAddress, relayIp, clientMac, broadcast); |
| mSrcIp = serverAddress; |
| } |
| |
| public String toString() { |
| String s = super.toString(); |
| String dnsServers = ", DNS servers: "; |
| |
| if (mDnsServers != null) { |
| for (Inet4Address dnsServer: mDnsServers) { |
| dnsServers += dnsServer + " "; |
| } |
| } |
| |
| return s + " OFFER, ip " + mYourIp + ", mask " + mSubnetMask + |
| dnsServers + ", gateways " + mGateways + |
| " lease time " + mLeaseTime + ", domain " + mDomainName; |
| } |
| |
| /** |
| * Fills in a packet with the specified OFFER attributes. |
| */ |
| 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 server-generated OFFER packet. |
| */ |
| void finishPacket(ByteBuffer buffer) { |
| addTlv(buffer, DHCP_MESSAGE_TYPE, DHCP_MESSAGE_TYPE_OFFER); |
| addTlv(buffer, DHCP_SERVER_IDENTIFIER, mServerIdentifier); |
| |
| addCommonServerTlvs(buffer); |
| addTlvEnd(buffer); |
| } |
| } |