17da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttpackage android.net.dhcp; 27da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 37da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.net.InetAddress; 47da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.net.UnknownHostException; 57da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.nio.ByteBuffer; 67da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.nio.ByteOrder; 7d396a448b2e36e29598c954b64bfddef73f3fae0Elliott Hughesimport java.nio.charset.StandardCharsets; 87da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.nio.ShortBuffer; 97da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.util.ArrayList; 117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttimport java.util.List; 127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt/** 147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Defines basic data and operations needed to build and use packets for the 157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP protocol. Subclasses create the specific packets used at each 167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * stage of the negotiation. 177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnuttabstract class DhcpPacket { 197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final String TAG = "DhcpPacket"; 207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Packet encapsulations. 237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static final int ENCAP_L2 = 0; // EthernetII header included 257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static final int ENCAP_L3 = 1; // IP/UDP header included 267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static final int ENCAP_BOOTP = 2; // BOOTP contents only 277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * IP layer definitions. 307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static final byte IP_TYPE_UDP = (byte) 0x11; 327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * IP: Version 4, Header Length 20 bytes 357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static final byte IP_VERSION_HEADER_LEN = (byte) 0x45; 377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * IP: Flags 0, Fragment Offset 0, Don't Fragment 407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static final short IP_FLAGS_OFFSET = (short) 0x4000; 427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * IP: TOS 457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static final byte IP_TOS_LOWDELAY = (byte) 0x10; 477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * IP: TTL -- use default 64 from RFC1340 507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static final byte IP_TTL = (byte) 0x40; 527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The client DHCP port. 557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt static final short DHCP_CLIENT = (short) 68; 577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The server DHCP port. 607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt static final short DHCP_SERVER = (short) 67; 627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The message op code indicating a request from a client. 657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_BOOTREQUEST = (byte) 1; 677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The message op code indicating a response from the server. 707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_BOOTREPLY = (byte) 2; 727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The code type used to identify an Ethernet MAC address in the 757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Client-ID field. 767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte CLIENT_ID_ETHER = (byte) 1; 787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The maximum length of a packet that can be constructed. 817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final int MAX_LENGTH = 1500; 837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Subnet Mask 867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_SUBNET_MASK = 1; 887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected InetAddress mSubnetMask; 897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Router 927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_ROUTER = 3; 947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected InetAddress mGateway; 957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP DNS Server 987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_DNS_SERVER = 6; 1007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected List<InetAddress> mDnsServers; 1017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Host Name 1047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_HOST_NAME = 12; 1067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected String mHostName; 1077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP DOMAIN NAME 1107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_DOMAIN_NAME = 15; 1127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected String mDomainName; 1137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP BROADCAST ADDRESS 1167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_BROADCAST_ADDRESS = 28; 1187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected InetAddress mBroadcastAddress; 1197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Requested IP Address 1227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_REQUESTED_IP = 50; 1247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected InetAddress mRequestedIp; 1257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Lease Time 1287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_LEASE_TIME = 51; 1307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected Integer mLeaseTime; 1317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Message Type 1347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE = 53; 1367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // the actual type values 1377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_DISCOVER = 1; 1387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_OFFER = 2; 1397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_REQUEST = 3; 1407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_DECLINE = 4; 1417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_ACK = 5; 1427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_NAK = 6; 1437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE_TYPE_INFORM = 8; 1447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Server Identifier 1477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_SERVER_IDENTIFIER = 54; 1497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected InetAddress mServerIdentifier; 1507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Parameter List 1537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_PARAMETER_LIST = 55; 1557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected byte[] mRequestedParams; 1567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP MESSAGE 1597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_MESSAGE = 56; 1617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected String mMessage; 1627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Renewal Time Value 1657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_RENEWAL_TIME = 58; 1677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: Vendor Class Identifier 1707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_VENDOR_CLASS_ID = 60; 1727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP Optional Type: DHCP Client Identifier 1757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected static final byte DHCP_CLIENT_IDENTIFIER = 61; 1777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The transaction identifier used in this particular DHCP negotiation 1807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected final int mTransId; 1827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The IP address of the client host. This address is typically 1857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * proposed by the client (from an earlier DHCP negotiation) or 1867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * supplied by the server. 1877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected final InetAddress mClientIp; 1897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected final InetAddress mYourIp; 1907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private final InetAddress mNextIp; 1917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private final InetAddress mRelayIp; 1927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Does the client request a broadcast response? 1957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 1967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected boolean mBroadcast; 1977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 1987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 1997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * The six-octet MAC of the client. 2007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected final byte[] mClientMac; 2027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 2047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Asks the packet object to signal the next operation in the DHCP 2057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * protocol. The available actions are methods defined in the 2067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DhcpStateMachine interface. 2077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public abstract void doNextOp(DhcpStateMachine stateMachine); 2097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 2117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Asks the packet object to create a ByteBuffer serialization of 2127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * the packet for transmission. 2137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public abstract ByteBuffer buildPacket(int encap, short destUdp, 2157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short srcUdp); 2167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 2187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Allows the concrete class to fill in packet-type-specific details, 2197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * typically optional parameters at the end of the packet. 2207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt abstract void finishPacket(ByteBuffer buffer); 2227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected DhcpPacket(int transId, InetAddress clientIp, InetAddress yourIp, 2247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress nextIp, InetAddress relayIp, 2257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] clientMac, boolean broadcast) { 2267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mTransId = transId; 2277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mClientIp = clientIp; 2287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mYourIp = yourIp; 2297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mNextIp = nextIp; 2307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mRelayIp = relayIp; 2317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mClientMac = clientMac; 2327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt mBroadcast = broadcast; 2337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 2347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 2367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Returns the transaction ID. 2377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public int getTransactionId() { 2397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return mTransId; 2407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 2417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 2437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Creates a new L3 packet (including IP header) containing the 2447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * DHCP udp packet. This method relies upon the delegated method 2457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * finishPacket() to insert the per-packet contents. 2467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 2477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void fillInPacket(int encap, InetAddress destIp, 2487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress srcIp, short destUdp, short srcUdp, ByteBuffer buf, 2497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte requestCode, boolean broadcast) { 2507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] destIpArray = destIp.getAddress(); 2517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] srcIpArray = srcIp.getAddress(); 2527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int ipLengthOffset = 0; 2537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int ipChecksumOffset = 0; 2547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int endIpHeader = 0; 2557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int udpHeaderOffset = 0; 2567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int udpLengthOffset = 0; 2577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int udpChecksumOffset = 0; 2587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.clear(); 2607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.order(ByteOrder.BIG_ENDIAN); 2617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // if a full IP packet needs to be generated, put the IP & UDP 2637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // headers in place, and pre-populate with artificial values 2647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // needed to seed the IP checksum. 2657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (encap == ENCAP_L3) { 2667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // fake IP header, used in the IP-header checksum 2677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(IP_VERSION_HEADER_LEN); 2687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(IP_TOS_LOWDELAY); // tos: IPTOS_LOWDELAY 2697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ipLengthOffset = buf.position(); 2707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short)0); // length 2717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short)0); // id 2727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(IP_FLAGS_OFFSET); // ip offset: don't fragment 2737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(IP_TTL); // TTL: use default 64 from RFC1340 2747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(IP_TYPE_UDP); 2757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ipChecksumOffset = buf.position(); 2767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0); // checksum 2777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(srcIpArray); 2797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(destIpArray); 2807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt endIpHeader = buf.position(); 2817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // UDP header 2837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpHeaderOffset = buf.position(); 2847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(srcUdp); 2857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(destUdp); 2867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpLengthOffset = buf.position(); 2877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0); // length 2887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpChecksumOffset = buf.position(); 2897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0); // UDP checksum -- initially zero 2907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 2917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 2927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // DHCP payload 2937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(requestCode); 2947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 1); // Hardware Type: Ethernet 2957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) mClientMac.length); // Hardware Address Length 2967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 0); // Hop Count 2977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putInt(mTransId); // Transaction ID 2987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0); // Elapsed Seconds 2997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (broadcast) { 3017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0x8000); // Flags 3027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } else { 3037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort((short) 0x0000); // Flags 3047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(mClientIp.getAddress()); 3077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(mYourIp.getAddress()); 3087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(mNextIp.getAddress()); 3097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(mRelayIp.getAddress()); 3107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(mClientMac); 3117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.position(buf.position() + 3127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt (16 - mClientMac.length) // pad addr to 16 bytes 3137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt + 64 // empty server host name (64 bytes) 3147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt + 128); // empty boot file name (128 bytes) 3157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putInt(0x63825363); // magic number 3167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt finishPacket(buf); 3177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // round up to an even number of octets 3197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if ((buf.position() & 1) == 1) { 3207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 0); 3217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // If an IP packet is being built, the IP & UDP checksums must be 3247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // computed. 3257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (encap == ENCAP_L3) { 3267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // fix UDP header: insert length 3277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short udpLen = (short)(buf.position() - udpHeaderOffset); 3287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(udpLengthOffset, udpLen); 3297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // fix UDP header: checksum 3307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // checksum for UDP at udpChecksumOffset 3317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int udpSeed = 0; 3327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // apply IPv4 pseudo-header. Read IP address src and destination 3347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // values from the IP header and accumulate checksum. 3357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += intAbs(buf.getShort(ipChecksumOffset + 2)); 3367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += intAbs(buf.getShort(ipChecksumOffset + 4)); 3377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += intAbs(buf.getShort(ipChecksumOffset + 6)); 3387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += intAbs(buf.getShort(ipChecksumOffset + 8)); 3397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // accumulate extra data for the pseudo-header 3417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += IP_TYPE_UDP; 3427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpSeed += udpLen; 3437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // and compute UDP checksum 3447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(udpChecksumOffset, (short) checksum(buf, udpSeed, 3457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt udpHeaderOffset, 3467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.position())); 3477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // fix IP header: insert length 3487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(ipLengthOffset, (short)buf.position()); 3497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // fixup IP-header checksum 3507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putShort(ipChecksumOffset, 3517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt (short) checksum(buf, 0, 0, endIpHeader)); 3527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 3567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Converts a signed short value to an unsigned int value. Needed 3577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * because Java does not have unsigned types. 3587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 3597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private int intAbs(short v) { 3607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (v < 0) { 3617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int r = v + 65536; 3627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return r; 3637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } else { 3647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return(v); 3657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 3697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Performs an IP checksum (used in IP header and across UDP 3707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * payload) on the specified portion of a ByteBuffer. The seed 3717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * allows the checksum to commence with a specified value. 3727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 3737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private int checksum(ByteBuffer buf, int seed, int start, int end) { 3747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int sum = seed; 3757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int bufPosition = buf.position(); 3767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // set position of original ByteBuffer, so that the ShortBuffer 3787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // will be correctly initialized 3797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.position(start); 3807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ShortBuffer shortBuf = buf.asShortBuffer(); 3817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // re-set ByteBuffer position 3837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.position(bufPosition); 3847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short[] shortArray = new short[(end - start) / 2]; 3867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt shortBuf.get(shortArray); 3877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (short s : shortArray) { 3897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt sum += intAbs(s); 3907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 3917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt start += shortArray.length * 2; 3937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // see if a singleton byte remains 3957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (end != start) { 3967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short b = buf.get(start); 3977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 3987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // make it unsigned 3997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (b < 0) { 4007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt b += 256; 4017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt sum += b * 256; 4047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt sum = ((sum >> 16) & 0xFFFF) + (sum & 0xFFFF); 4077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt sum = ((sum + ((sum >> 16) & 0xFFFF)) & 0xFFFF); 4087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int negated = ~sum; 4097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return intAbs((short) negated); 4107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing a single byte value. 4147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, byte value) { 4167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(type); 4177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 1); 4187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(value); 4197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing an array of bytes. 4237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, byte[] payload) { 4257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (payload != null) { 4267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(type); 4277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) payload.length); 4287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(payload); 4297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing an IP address. 4347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, InetAddress addr) { 4367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (addr != null) { 4377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt addTlv(buf, type, addr.getAddress()); 4387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing a list of IP addresses. 4437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, List<InetAddress> addrs) { 4457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (addrs != null && addrs.size() > 0) { 4467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(type); 4477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte)(4 * addrs.size())); 4487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (InetAddress addr : addrs) { 4507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(addr.getAddress()); 4517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing a simple integer 4577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, Integer value) { 4597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (value != null) { 4607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(type); 4617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 4); 4627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.putInt(value.intValue()); 4637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds an optional parameter containing and ASCII string. 4687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlv(ByteBuffer buf, byte type, String str) { 4707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (str != null) { 4717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put(type); 4727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) str.length()); 4737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (int i = 0; i < str.length(); i++) { 4757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) str.charAt(i)); 4767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Adds the special end-of-optional-parameters indicator. 4827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt protected void addTlvEnd(ByteBuffer buf) { 4847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.put((byte) 0xFF); 4857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 4867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 4887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Converts a MAC from an array of octets to an ASCII string. 4897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 4907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static String macToString(byte[] mac) { 4917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String macAddr = ""; 4927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (int i = 0; i < mac.length; i++) { 4947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String hexString = "0" + Integer.toHexString(mac[i]); 4957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 4967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // substring operation grabs the last 2 digits: this 4977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // allows signed bytes to be converted correctly. 4987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt macAddr += hexString.substring(hexString.length() - 2); 4997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (i != (mac.length - 1)) { 5017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt macAddr += ":"; 5027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return macAddr; 5067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public String toString() { 5097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String macAddr = macToString(mClientMac); 5107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return macAddr; 5127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 5157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Reads a four-octet value from a ByteBuffer and construct 5167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * an IPv4 address from that value. 5177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 5187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static InetAddress readIpAddress(ByteBuffer packet) { 5197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress result = null; 5207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] ipAddr = new byte[4]; 5217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(ipAddr); 5227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt try { 5247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt result = InetAddress.getByAddress(ipAddr); 5257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } catch (UnknownHostException ex) { 5267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // ipAddr is numeric, so this should not be 5277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // triggered. However, if it is, just nullify 5287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt result = null; 5297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return result; 5327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 5357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Reads a string of specified length from the buffer. 5367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 5377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt private static String readAsciiString(ByteBuffer buf, int byteCount) { 5387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] bytes = new byte[byteCount]; 5397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt buf.get(bytes); 540d396a448b2e36e29598c954b64bfddef73f3fae0Elliott Hughes return new String(bytes, 0, bytes.length, StandardCharsets.US_ASCII); 5417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 5447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Creates a concrete DhcpPacket from the supplied ByteBuffer. The 5457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * buffer may have an L2 encapsulation (which is the full EthernetII 5467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * format starting with the source-address MAC) or an L3 encapsulation 5477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * (which starts with the IP header). 5487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * <br> 5497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * A subset of the optional parameters are parsed and are stored 5507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * in object fields. 5517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 5527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static DhcpPacket decodeFullPacket(ByteBuffer packet, int pktType) 5537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt { 5547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // bootp parameters 5557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int transactionId; 5567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress clientIp; 5577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress yourIp; 5587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress nextIp; 5597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress relayIp; 5607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] clientMac; 561045b166ac27c3b7a67993b029f03088042bf4d5aStan Chesnutt List<InetAddress> dnsServers = new ArrayList<InetAddress>(); 5627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress gateway = null; // aka router 5637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt Integer leaseTime = null; 5647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress serverIdentifier = null; 5657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress netMask = null; 5667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String message = null; 5677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String vendorId = null; 5687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] expectedParams = null; 5697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String hostName = null; 5707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt String domainName = null; 5717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress ipSrc = null; 5727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress ipDst = null; 5737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress bcAddr = null; 5747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress requestedIp = null; 5757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // dhcp options 5777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte dhcpType = (byte) 0xFF; 5787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.order(ByteOrder.BIG_ENDIAN); 5807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // check to see if we need to parse L2, IP, and UDP encaps 5827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (pktType == ENCAP_L2) { 5837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // System.out.println("buffer len " + packet.limit()); 5847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] l2dst = new byte[6]; 5857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] l2src = new byte[6]; 5867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(l2dst); 5887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(l2src); 5897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short l2type = packet.getShort(); 5917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (l2type != 0x0800) 5937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 5947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 5957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 5967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if ((pktType == ENCAP_L2) || (pktType == ENCAP_L3)) { 5977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // assume l2type is 0x0800, i.e. IP 5987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipType = packet.get(); 5997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // System.out.println("ipType is " + ipType); 6007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipDiffServicesField = packet.get(); 6017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short ipTotalLength = packet.getShort(); 6027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short ipIdentification = packet.getShort(); 6037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipFlags = packet.get(); 6047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipFragOffset = packet.get(); 6057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipTTL = packet.get(); 6067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte ipProto = packet.get(); 6077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short ipChksm = packet.getShort(); 6087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ipSrc = readIpAddress(packet); 6107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ipDst = readIpAddress(packet); 6117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (ipProto != IP_TYPE_UDP) // UDP 6137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 6147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // assume UDP 6167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short udpSrcPort = packet.getShort(); 6177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short udpDstPort = packet.getShort(); 6187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short udpLen = packet.getShort(); 6197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short udpChkSum = packet.getShort(); 6207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if ((udpSrcPort != DHCP_SERVER) && (udpSrcPort != DHCP_CLIENT)) 6227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 6237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 6247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // assume bootp 6267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte type = packet.get(); 6277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte hwType = packet.get(); 6287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte addrLen = packet.get(); 6297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte hops = packet.get(); 6307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId = packet.getInt(); 6317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short elapsed = packet.getShort(); 6327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt short bootpFlags = packet.getShort(); 6337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt boolean broadcast = (bootpFlags & 0x8000) != 0; 6347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] ipv4addr = new byte[4]; 6357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt try { 6377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(ipv4addr); 6387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientIp = InetAddress.getByAddress(ipv4addr); 6397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(ipv4addr); 6407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt yourIp = InetAddress.getByAddress(ipv4addr); 6417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(ipv4addr); 6427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt nextIp = InetAddress.getByAddress(ipv4addr); 6437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(ipv4addr); 6447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt relayIp = InetAddress.getByAddress(ipv4addr); 6457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } catch (UnknownHostException ex) { 6467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 6477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 6487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientMac = new byte[addrLen]; 6507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(clientMac); 6517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // skip over address padding (16 octets allocated) 6537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.position(packet.position() + (16 - addrLen) 6547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt + 64 // skip server host name (64 chars) 6557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt + 128); // skip boot file name (128 chars) 6567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int dhcpMagicCookie = packet.getInt(); 6587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (dhcpMagicCookie != 0x63825363) 6607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 6617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // parse options 6637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt boolean notFinishedOptions = true; 6647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt while ((packet.position() < packet.limit()) && notFinishedOptions) { 6667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte optionType = packet.get(); 6677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (optionType == (byte) 0xFF) { 6697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt notFinishedOptions = false; 6707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } else { 6717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte optionLen = packet.get(); 6727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int expectedLen = 0; 6737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt switch(optionType) { 6757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_SUBNET_MASK: 6767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt netMask = readIpAddress(packet); 6777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 6787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 6797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_ROUTER: 6807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt gateway = readIpAddress(packet); 6817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 6827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 6837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_DNS_SERVER: 6847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 0; 6857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 6867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (expectedLen = 0; expectedLen < optionLen; 6877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen += 4) { 6887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt dnsServers.add(readIpAddress(packet)); 6897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 6907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 6917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_HOST_NAME: 6927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 6937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt hostName = readAsciiString(packet, optionLen); 6947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 6957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_DOMAIN_NAME: 6967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 6977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt domainName = readAsciiString(packet, optionLen); 6987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 6997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_BROADCAST_ADDRESS: 7007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt bcAddr = readIpAddress(packet); 7017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 7027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_REQUESTED_IP: 7047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt requestedIp = readIpAddress(packet); 7057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 7067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_LEASE_TIME: 7087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt leaseTime = Integer.valueOf(packet.getInt()); 7097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 7107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE: 7127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt dhcpType = packet.get(); 7137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 1; 7147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_SERVER_IDENTIFIER: 7167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt serverIdentifier = readIpAddress(packet); 7177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = 4; 7187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_PARAMETER_LIST: 7207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedParams = new byte[optionLen]; 7217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(expectedParams); 7227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 7237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE: 7257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 7267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt message = readAsciiString(packet, optionLen); 7277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_VENDOR_CLASS_ID: 7297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 7307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt vendorId = readAsciiString(packet, optionLen); 7317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_CLIENT_IDENTIFIER: { // Client identifier 7337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] id = new byte[optionLen]; 7347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt packet.get(id); 7357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen = optionLen; 7367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } break; 7377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt default: 7387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt // ignore any other parameters 7397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt for (int i = 0; i < optionLen; i++) { 7407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt expectedLen++; 7417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte throwaway = packet.get(); 7427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 7457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt if (expectedLen != optionLen) { 7467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 7477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 7517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket newPacket; 7527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 7537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt switch(dhcpType) { 7547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case -1: return null; 7557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_DISCOVER: 7567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpDiscoverPacket( 7577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientMac, broadcast); 7587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_OFFER: 7607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpOfferPacket( 7617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, broadcast, ipSrc, yourIp, clientMac); 7627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_REQUEST: 7647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpRequestPacket( 7657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientIp, clientMac, broadcast); 7667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_DECLINE: 7687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpDeclinePacket( 7697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientIp, yourIp, nextIp, relayIp, 7707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientMac); 7717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_ACK: 7737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpAckPacket( 7747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, broadcast, ipSrc, yourIp, clientMac); 7757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_NAK: 7777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpNakPacket( 7787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientIp, yourIp, nextIp, relayIp, 7797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientMac); 7807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt case DHCP_MESSAGE_TYPE_INFORM: 7827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket = new DhcpInformPacket( 7837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientIp, yourIp, nextIp, relayIp, 7847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientMac); 7857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt break; 7867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt default: 7877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt System.out.println("Unimplemented type: " + dhcpType); 7887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return null; 7897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 7907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 7917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mBroadcastAddress = bcAddr; 7927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mDnsServers = dnsServers; 7937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mDomainName = domainName; 7947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mGateway = gateway; 7957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mHostName = hostName; 7967da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mLeaseTime = leaseTime; 7977da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mMessage = message; 7987da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mRequestedIp = requestedIp; 7997da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mRequestedParams = expectedParams; 8007da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mServerIdentifier = serverIdentifier; 8017da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt newPacket.mSubnetMask = netMask; 8027da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return newPacket; 8037da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8047da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8057da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8067da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Parse a packet from an array of bytes. 8077da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8087da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static DhcpPacket decodeFullPacket(byte[] packet, int pktType) 8097da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt { 8107da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ByteBuffer buffer = ByteBuffer.wrap(packet).order(ByteOrder.BIG_ENDIAN); 8117da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return decodeFullPacket(buffer, pktType); 8127da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8137da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8147da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8157da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Builds a DHCP-DISCOVER packet from the required specified 8167da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * parameters. 8177da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8187da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static ByteBuffer buildDiscoverPacket(int encap, int transactionId, 8197da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] clientMac, boolean broadcast, byte[] expectedParams) { 8207da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket pkt = new DhcpDiscoverPacket( 8217da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, clientMac, broadcast); 8227da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mRequestedParams = expectedParams; 8237da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return pkt.buildPacket(encap, DHCP_SERVER, DHCP_CLIENT); 8247da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8257da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8267da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8277da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Builds a DHCP-OFFER packet from the required specified 8287da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * parameters. 8297da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8307da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static ByteBuffer buildOfferPacket(int encap, int transactionId, 8317da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt boolean broadcast, InetAddress serverIpAddr, InetAddress clientIpAddr, 8327da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] mac, Integer timeout, InetAddress netMask, InetAddress bcAddr, 8337da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress gateway, List<InetAddress> dnsServers, 8347da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress dhcpServerIdentifier, String domainName) { 8357da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket pkt = new DhcpOfferPacket( 8367da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, broadcast, serverIpAddr, clientIpAddr, mac); 8377da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mGateway = gateway; 8387da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mDnsServers = dnsServers; 8397da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mLeaseTime = timeout; 8407da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mDomainName = domainName; 8417da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mServerIdentifier = dhcpServerIdentifier; 8427da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mSubnetMask = netMask; 8437da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mBroadcastAddress = bcAddr; 8447da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return pkt.buildPacket(encap, DHCP_CLIENT, DHCP_SERVER); 8457da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8467da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8477da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8487da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Builds a DHCP-ACK packet from the required specified parameters. 8497da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8507da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static ByteBuffer buildAckPacket(int encap, int transactionId, 8517da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt boolean broadcast, InetAddress serverIpAddr, InetAddress clientIpAddr, 8527da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] mac, Integer timeout, InetAddress netMask, InetAddress bcAddr, 8537da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress gateway, List<InetAddress> dnsServers, 8547da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress dhcpServerIdentifier, String domainName) { 8557da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket pkt = new DhcpAckPacket( 8567da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt transactionId, broadcast, serverIpAddr, clientIpAddr, mac); 8577da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mGateway = gateway; 8587da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mDnsServers = dnsServers; 8597da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mLeaseTime = timeout; 8607da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mDomainName = domainName; 8617da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mSubnetMask = netMask; 8627da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mServerIdentifier = dhcpServerIdentifier; 8637da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mBroadcastAddress = bcAddr; 8647da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return pkt.buildPacket(encap, DHCP_CLIENT, DHCP_SERVER); 8657da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8667da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8677da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8687da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Builds a DHCP-NAK packet from the required specified parameters. 8697da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8707da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static ByteBuffer buildNakPacket(int encap, int transactionId, 8717da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress serverIpAddr, InetAddress clientIpAddr, byte[] mac) { 8727da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket pkt = new DhcpNakPacket(transactionId, clientIpAddr, 8737da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt serverIpAddr, serverIpAddr, serverIpAddr, mac); 8747da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mMessage = "requested address not available"; 8757da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mRequestedIp = clientIpAddr; 8767da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return pkt.buildPacket(encap, DHCP_CLIENT, DHCP_SERVER); 8777da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8787da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt 8797da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt /** 8807da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt * Builds a DHCP-REQUEST packet from the required specified parameters. 8817da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt */ 8827da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt public static ByteBuffer buildRequestPacket(int encap, 8837da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt int transactionId, InetAddress clientIp, boolean broadcast, 8847da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt byte[] clientMac, InetAddress requestedIpAddress, 8857da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt InetAddress serverIdentifier, byte[] requestedParams, String hostName) { 8867da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt DhcpPacket pkt = new DhcpRequestPacket(transactionId, clientIp, 8877da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt clientMac, broadcast); 8887da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mRequestedIp = requestedIpAddress; 8897da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mServerIdentifier = serverIdentifier; 8907da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mHostName = hostName; 8917da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt pkt.mRequestedParams = requestedParams; 8927da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt ByteBuffer result = pkt.buildPacket(encap, DHCP_SERVER, DHCP_CLIENT); 8937da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt return result; 8947da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt } 8957da02ad3b7a8a0b13a2ccc84e666baa8e6370482Stan Chesnutt} 896