1 /* 2 * Copyright (C) 2010 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 17 package android.net.dhcp; 18 19 import android.util.Log; 20 21 import java.net.Inet4Address; 22 import java.nio.ByteBuffer; 23 24 /** 25 * This class implements the DHCP-REQUEST packet. 26 */ 27 class DhcpRequestPacket extends DhcpPacket { 28 /** 29 * Generates a REQUEST packet with the specified parameters. 30 */ 31 DhcpRequestPacket(int transId, short secs, Inet4Address clientIp, byte[] clientMac, 32 boolean broadcast) { 33 super(transId, secs, clientIp, INADDR_ANY, INADDR_ANY, INADDR_ANY, clientMac, broadcast); 34 } 35 36 public String toString() { 37 String s = super.toString(); 38 return s + " REQUEST, desired IP " + mRequestedIp + " from host '" 39 + mHostName + "', param list length " 40 + (mRequestedParams == null ? 0 : mRequestedParams.length); 41 } 42 43 /** 44 * Fills in a packet with the requested REQUEST attributes. 45 */ 46 public ByteBuffer buildPacket(int encap, short destUdp, short srcUdp) { 47 ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH); 48 49 fillInPacket(encap, INADDR_BROADCAST, INADDR_ANY, destUdp, srcUdp, 50 result, DHCP_BOOTREQUEST, mBroadcast); 51 result.flip(); 52 return result; 53 } 54 55 /** 56 * Adds the optional parameters to the client-generated REQUEST packet. 57 */ 58 void finishPacket(ByteBuffer buffer) { 59 addTlv(buffer, DHCP_MESSAGE_TYPE, DHCP_MESSAGE_TYPE_REQUEST); 60 addTlv(buffer, DHCP_CLIENT_IDENTIFIER, getClientId()); 61 if (!INADDR_ANY.equals(mRequestedIp)) { 62 addTlv(buffer, DHCP_REQUESTED_IP, mRequestedIp); 63 } 64 if (!INADDR_ANY.equals(mServerIdentifier)) { 65 addTlv(buffer, DHCP_SERVER_IDENTIFIER, mServerIdentifier); 66 } 67 addCommonClientTlvs(buffer); 68 addTlv(buffer, DHCP_PARAMETER_LIST, mRequestedParams); 69 addTlvEnd(buffer); 70 } 71 } 72
