Msg File src/inet/applications/dhcp/DhcpMessage.msg

Name	Type	Description
DhcpOpcode	enum	(no description)
DhcpMessageType	enum	(no description)
DhcpOptionCode	enum	(no description)
DhcpTimerType	enum	DHCP timer types (RFC 2131 4.4.5)
DhcpOptions	class	Represents options in a DHCP message. In the DHCP protocol, options are added to the message as tagged data items. In the simulation, this DhcpOptions class statically holds the union of all options actually used by the DHCP protocol models. Options absent from a packet are represented by empty/unfilled DhcpOptions fields.
DhcpMessage	class	Represents a DHCP message. DHCP (Dynamic Host Configuration Protocol, RFC 2131) provides a framework for passing configuration information to hosts on a TCP/IP network.

Source code

//
// Copyright (C) 2008 Juan-Carlos Maureira
// Copyright (C) INRIA
// Copyright (C) 2013 OpenSim Ltd.
//
// SPDX-License-Identifier: LGPL-3.0-or-later
//

import inet.common.INETDefs;
import inet.common.packet.chunk.Chunk;
import inet.networklayer.contract.ipv4.Ipv4Address;
import inet.linklayer.common.MacAddress;

namespace inet;

enum DhcpOpcode
{
    BOOTREQUEST = 1;
    BOOTREPLY = 2;
}

enum DhcpMessageType
{
    DHCPDISCOVER = 1;
    DHCPOFFER = 2;
    DHCPREQUEST = 3;
    DHCPDECLINE = 4;
    DHCPACK = 5;
    DHCPNAK = 6;
    DHCPRELEASE = 7;
    DHCPINFORM = 8;
}

enum DhcpOptionCode
{
    DHCP_MSG_TYPE = 53;
    CLIENT_ID = 61;
    HOSTNAME = 12;
    REQUESTED_IP = 50;
    PARAM_LIST = 55;
    SUBNET_MASK = 1;
    ROUTER = 3;
    DNS = 6;
    NTP_SRV = 42;
    RENEWAL_TIME = 58;
    REBIND_TIME = 59;
    LEASE_TIME = 51;
    SERVER_ID = 54;
}

// DHCP timer types (RFC 2131 4.4.5)
enum DhcpTimerType
{
    WAIT_OFFER = 1;
    WAIT_ACK = 2;
    T1 = 3;
    T2 = 4;
    LEASE_TIMEOUT = 5;
    START_DHCP = 6;
}

//
// Represents options in a DHCP message. In the DHCP protocol, options are
// added to the message as tagged data items. In the simulation, this DhcpOptions
// class statically holds the union of all options actually used by the DHCP
// protocol models. Options absent from a packet are represented by empty/unfilled
// DhcpOptions fields.
//
// @see DhcpMessage, DhcpClient, DhcpServer
//
class DhcpOptions extends cObject
{
    @packetData;
    DhcpMessageType messageType; // to convey the type of the DHCP message
    string hostName; // name of the client
    DhcpOptionCode parameterRequestList[]; // used by a DHCP client to request values for specified configuration parameters
    MacAddress clientIdentifier; // used by DHCP clients to specify their unique identifier
    Ipv4Address requestedIp; // used in a client request (DHCPDISCOVER) to allow the client to request that a particular IP address be assigned
    Ipv4Address subnetMask; // client's subnet mask
    Ipv4Address router[]; // IP addresses for routers on the client's subnet
    Ipv4Address dns[]; // list of DNSs available to the client
    Ipv4Address ntp[]; // list of IP addresses indicating NTP servers available to the client
    Ipv4Address serverIdentifier; // client use this field as the destination address for any unicast DHCP messages to the server
    simtime_t renewalTime; // time interval (T1) from address assignment until the client transitions to the RENEWING state
    simtime_t rebindingTime; // time interval (T2) from address assignment until the client transitions to the REBINDING state
    simtime_t leaseTime; // request for lease time (client), offered lease time (server)
}

//
// Represents a DHCP message. DHCP (Dynamic Host Configuration Protocol, RFC 2131)
// provides a framework for passing configuration information to hosts on a TCP/IP network.
//
// @see DhcpClient, DhcpServer
//
class DhcpMessage extends FieldsChunk
{
    DhcpOpcode op; // message op code / message type. 1 = BOOTREQUEST, 2 = BOOTREPLY
    int htype; // hardware address type, see Arp section in "Assigned Numbers" RFC; e.g., '1' = 10mb ethernet
    int hlen; // hardware address length (e.g.  '6' for 10mb ethernet)
    int hops; // client sets to zero, optionally used by relay agents when booting via a relay agent
    unsigned int xid; // transaction ID, a random number chosen by the client, used by the client and server to associate messages and responses between a client and a server
    int secs; // filled in by client, seconds elapsed since client began address acquisition or renewal process
    bool broadcast; // the broadcast bit in the flags field
    uint16_t reserved = 0; // MUST BE ZERO (reserved for future use)
    Ipv4Address ciaddr; // client IP address; only filled in if client is in BOUND, RENEW or REBINDING state and can respond to Arp requests
    Ipv4Address yiaddr; // 'your' (client) IP address
    Ipv4Address giaddr; // relay agent IP address, used in booting via a relay agent
    MacAddress chaddr; // client hardware address (MAC)
    string sname; // optional server host name
    string file; // boot file name (unused in the simulation)
    DhcpOptions options; // holds DHCP options
}