Dynamic Host Configuration Protocol (DHCP) client application. More...

#include <DhcpClient.h>

Inheritance diagram for DhcpClient:

Data Structures
struct	Header
	Protocol packet header. More...

Public Member Functions
	DhcpClient (int argc, char **argv)
	Class constructor. More...

virtual	~DhcpClient ()
	Class destructor. More...

virtual Result	initialize ()
	Initialize the application. More...

virtual Result	exec ()
	Execute the application event loop. More...

Public Member Functions inherited from POSIXApplication
	POSIXApplication (int argc, char **argv)
	Class constructor. More...

virtual	~POSIXApplication ()
	Class destructor. More...

Public Member Functions inherited from Application
	Application (int argc, char **argv)
	Class constructor. More...

virtual	~Application ()
	Class destructor. More...

virtual int	run ()
	Run the application. More...

Private Types
enum	Operation { BootRequest = 1, BootResponse = 2 }
	DHCP operations. More...

enum	MessageType { Discover = 1, Offer = 2, Request = 3, Decline = 4, Ack = 5, Nak = 6, Release = 7 }
	DHCP message types. More...

enum	Options { SubnetMask = 1, Router = 3, DomainNameServer = 6, RequestedIP = 50, DhcpMessageType = 53, ServerIdentifier = 54, ParameterRequestList = 55, EndMark = 255 }
	DHCP options. More...

Private Member Functions
Result	setIpAddress (const char *device, const IPV4::Address ipAddr) const
	Set IP address on a device. More...

Result	discover (const IPV4::Address &ipAddr, const IPV4::Address &ipServer, const IPV4::Address &ipGateway) const
	Send DHCP Discover message. More...

Result	offer (IPV4::Address &ipAddr, IPV4::Address &ipServer, IPV4::Address &ipGateway) const
	Receive DHCP Offer message. More...

Result	request (const IPV4::Address &ipAddr, const IPV4::Address &ipServer, const IPV4::Address &ipGateway) const
	Send DHCP Request message. More...

Result	acknowledge (IPV4::Address &ipAddr, IPV4::Address &ipServer, IPV4::Address &ipGateway) const
	Receive DHCP Acknowledge message. More...

Result	sendBootRequest (const DhcpClient::MessageType messageType, const IPV4::Address &ipAddr, const IPV4::Address &ipServer, const IPV4::Address &ipGateway) const
	Send DHCP boot request. More...

Result	receiveBootResponse (const DhcpClient::MessageType messageType, IPV4::Address &ipAddr, IPV4::Address &ipServer, IPV4::Address &ipGateway) const
	Receive DHCP boot response. More...

Result	udpSend (const void *packet, const Size size) const
	Send UDP broadcast packet. More...

Result	udpReceive (void *packet, Size &size) const
	Receive UDP packet. More...

Private Attributes
NetworkClient *	m_client
	Network client. More...

int	m_socket
	UDP socket. More...

Ethernet::Address	m_etherAddress
	Host ethernet address. More...

u32	m_transactionId
	Transaction ID of the current request. More...

Static Private Attributes
static const u16	ServerPort = 67
	Server UDP port. More...

static const u16	ClientPort = 68
	Client UDP port. More...

static const Size	MaximumRetries = 25
	Maximum number of retries to receive an IP address. More...

static const u32	MagicValue = 0x63825363
	Magic number value for the packet header. More...

static const Size	ReceiveTimeoutMs = 500
	Timeout in milliseconds to wait for packet receive. More...

Additional Inherited Members
Public Types inherited from Application
enum	Result { Success, NotFound, IOError, InvalidArgument, ShowUsage, TimedOut, OutOfMemory }
	Result codes. More...

Protected Member Functions inherited from POSIXApplication
virtual Result	output (const char *string) const
	Print text to output. More...

int	runProgram (const char path, const char *argv)
	Runs an external program. More...

Protected Member Functions inherited from Application
virtual Result	output (String &string) const
	Print string to output. More...

ArgumentParser &	parser ()
	Get program arguments parser. More...

const ArgumentParser &	parser () const
	Get constant program arguments parser. More...

const ArgumentContainer &	arguments () const
	Get program arguments. More...

void	setVersion (const String &version)
	Set program version. More...

Protected Attributes inherited from Application
int	m_argc
	Input argument count. More...

char **	m_argv
	Input argument values. More...

Detailed Description

Dynamic Host Configuration Protocol (DHCP) client application.

See also: https://tools.ietf.org/html/rfc1541; https://tools.ietf.org/html/rfc2131; https://tools.ietf.org/html/rfc1533

Definition at line 36 of file DhcpClient.h.

Member Enumeration Documentation

◆ MessageType

enum DhcpClient::MessageType

private

DHCP message types.

Enumerator
Discover
Offer
Request
Decline
Ack
Nak
Release

Definition at line 88 of file DhcpClient.h.

◆ Operation

enum DhcpClient::Operation

private

DHCP operations.

Enumerator
BootRequest
BootResponse

Definition at line 79 of file DhcpClient.h.

◆ Options

enum DhcpClient::Options

private

DHCP options.

Enumerator
SubnetMask
Router
DomainNameServer
RequestedIP
DhcpMessageType
ServerIdentifier
ParameterRequestList
EndMark

Definition at line 102 of file DhcpClient.h.

Constructor & Destructor Documentation

◆ DhcpClient()

DhcpClient::DhcpClient	(	int	argc,
		char **	argv
	)

Class constructor.

Parameters

argc	Argument count
argv	Argument values

Definition at line 33 of file DhcpClient.cpp.

References m_etherAddress, Application::parser(), ArgumentParser::registerPositional(), MemoryBlock::set(), and ArgumentParser::setDescription().

◆ ~DhcpClient()

DhcpClient::~DhcpClient ( )

virtual

Class destructor.

Definition at line 45 of file DhcpClient.cpp.

References m_client.

Member Function Documentation

◆ acknowledge()

DhcpClient::Result DhcpClient::acknowledge	(	IPV4::Address &	ipAddr,
		IPV4::Address &	ipServer,
		IPV4::Address &	ipGateway
	)		const

private

Receive DHCP Acknowledge message.

Parameters

ipAddr	Acknowledged IP address on output
ipServer	Server IP address on output
ipGateway	Gateway IP address on output

Returns: Result code

Definition at line 205 of file DhcpClient.cpp.

References Ack, DEBUG, and receiveBootResponse().

Referenced by exec().

◆ discover()

DhcpClient::Result DhcpClient::discover	(	const IPV4::Address &	ipAddr,
		const IPV4::Address &	ipServer,
		const IPV4::Address &	ipGateway
	)		const

private

Send DHCP Discover message.

Parameters

ipAddr	Requested IP address
ipServer	Server IP address
ipGateway	Gateway IP address

Returns: Result code

Definition at line 180 of file DhcpClient.cpp.

References DEBUG, Discover, and sendBootRequest().

Referenced by exec().

◆ exec()

DhcpClient::Result DhcpClient::exec ( )

virtual

Execute the application event loop.

Returns: Result code

Implements Application.

Definition at line 106 of file DhcpClient.cpp.

References acknowledge(), Application::arguments(), DEBUG, discover(), ERROR, m_transactionId, MaximumRetries, Application::NotFound, offer(), request(), setIpAddress(), Application::Success, and IPV4::toString().

◆ initialize()

DhcpClient::Result DhcpClient::initialize ( )

virtual

Initialize the application.

Returns: Result code

Reimplemented from Application.

Definition at line 50 of file DhcpClient.cpp.

References Application::arguments(), NetworkClient::bindSocket(), BufferedFile::buffer(), ClientPort, MemoryBlock::copy(), NetworkClient::createSocket(), DEBUG, ERROR, ArgumentContainer::get(), NetworkClient::initialize(), Application::IOError, m_client, m_etherAddress, m_socket, BufferedFile::read(), BufferedFile::Success, Application::Success, NetworkClient::Success, and NetworkClient::UDP.

◆ offer()

DhcpClient::Result DhcpClient::offer	(	IPV4::Address &	ipAddr,
		IPV4::Address &	ipServer,
		IPV4::Address &	ipGateway
	)		const

private

Receive DHCP Offer message.

Parameters

ipAddr	Offered IP address on output
ipServer	Server IP address on output
ipGateway	Gateway IP address on output

Returns: Result code

Definition at line 188 of file DhcpClient.cpp.

References DEBUG, Offer, and receiveBootResponse().

Referenced by exec().

◆ receiveBootResponse()

DhcpClient::Result DhcpClient::receiveBootResponse	(	const DhcpClient::MessageType	messageType,
		IPV4::Address &	ipAddr,
		IPV4::Address &	ipServer,
		IPV4::Address &	ipGateway
	)		const

private

Receive DHCP boot response.

Parameters

messageType	Expected value for DHCP message type option
ipAddr	IP address on output
ipServer	Server IP address on output
ipGateway	Gateway IP address on output

Returns: Result code

Definition at line 272 of file DhcpClient.cpp.

References BootResponse, DhcpClient::Header::clientHardware, MemoryBlock::compare(), DEBUG, DhcpMessageType, DomainNameServer, EndMark, ERROR, Application::InvalidArgument, Application::IOError, m_etherAddress, m_transactionId, DhcpClient::Header::operation, ParameterRequestList, readBe32(), RequestedIP, Router, ServerIdentifier, SubnetMask, Application::Success, IPV4::toString(), DhcpClient::Header::transactionId, udpReceive(), and DhcpClient::Header::yourAddress.

Referenced by acknowledge(), and offer().

◆ request()

DhcpClient::Result DhcpClient::request	(	const IPV4::Address &	ipAddr,
		const IPV4::Address &	ipServer,
		const IPV4::Address &	ipGateway
	)		const

private

Send DHCP Request message.

Parameters

ipAddr	Requested IP address
ipServer	Server IP address
ipGateway	Gateway IP address

Returns: Result code

Definition at line 197 of file DhcpClient.cpp.

References DEBUG, Request, and sendBootRequest().

Referenced by exec().

◆ sendBootRequest()

DhcpClient::Result DhcpClient::sendBootRequest	(	const DhcpClient::MessageType	messageType,
		const IPV4::Address &	ipAddr,
		const IPV4::Address &	ipServer,
		const IPV4::Address &	ipGateway
	)		const

private

Send DHCP boot request.

Parameters

messageType	Value for the DHCP message type option
ipAddr	Requested IP address
ipServer	Server IP address
ipGateway	Gateway IP address

Returns: Result code

Definition at line 213 of file DhcpClient.cpp.

References BootRequest, DhcpClient::Header::clientHardware, MemoryBlock::copy(), DEBUG, DhcpMessageType, DomainNameServer, EndMark, DhcpClient::Header::hardwareLength, DhcpClient::Header::hardwareType, m_etherAddress, m_transactionId, DhcpClient::Header::magic, MagicValue, DhcpClient::Header::operation, ParameterRequestList, RequestedIP, Router, ServerIdentifier, MemoryBlock::set(), IPV4::toString(), DhcpClient::Header::transactionId, udpSend(), writeBe32(), and ZERO.

Referenced by discover(), and request().

◆ setIpAddress()

DhcpClient::Result DhcpClient::setIpAddress	(	const char *	device,
		const IPV4::Address	ipAddr
	)		const

private

Set IP address on a device.

Parameters

device	Name of the network device
ipAddr	IPV4 address to set

Returns: Result code

Definition at line 159 of file DhcpClient.cpp.

References DEBUG, ERROR, Application::IOError, BufferedFile::Success, Application::Success, IPV4::toString(), and BufferedFile::write().

Referenced by exec().

◆ udpReceive()

DhcpClient::Result DhcpClient::udpReceive	(	void *	packet,
		Size &	size
	)		const

private

Receive UDP packet.

Parameters

packet	Payload output
size	Output for number of bytes received

Returns: Result code

Definition at line 398 of file DhcpClient.cpp.

References sockaddr::addr, DEBUG, errno, ERROR, Application::IOError, m_client, m_socket, ReceiveTimeoutMs, recvfrom(), strerror(), Application::Success, NetworkClient::Success, IPV4::toString(), NetworkClient::UDP, and NetworkClient::waitSocket().

Referenced by receiveBootResponse().

◆ udpSend()

DhcpClient::Result DhcpClient::udpSend	(	const void *	packet,
		const Size	size
	)		const

private

Send UDP broadcast packet.

Parameters

packet	Payload to send
size	Number of bytes to send

Returns: Result code

Definition at line 376 of file DhcpClient.cpp.

References sockaddr::addr, DEBUG, errno, ERROR, Application::IOError, m_socket, sendto(), ServerPort, strerror(), and Application::Success.

Referenced by sendBootRequest().

Field Documentation

◆ ClientPort

const u16 DhcpClient::ClientPort = 68

staticprivate

Client UDP port.

Definition at line 44 of file DhcpClient.h.

Referenced by initialize().

◆ m_client

NetworkClient* DhcpClient::m_client

private

Network client.

Definition at line 263 of file DhcpClient.h.

Referenced by initialize(), udpReceive(), and ~DhcpClient().

◆ m_etherAddress

Ethernet::Address DhcpClient::m_etherAddress

private

Host ethernet address.

Definition at line 269 of file DhcpClient.h.

Referenced by DhcpClient(), initialize(), receiveBootResponse(), and sendBootRequest().

◆ m_socket

int DhcpClient::m_socket

private

UDP socket.

Definition at line 266 of file DhcpClient.h.

Referenced by initialize(), udpReceive(), and udpSend().

◆ m_transactionId

u32 DhcpClient::m_transactionId

private

Transaction ID of the current request.

Definition at line 272 of file DhcpClient.h.

Referenced by exec(), receiveBootResponse(), and sendBootRequest().

◆ MagicValue

const u32 DhcpClient::MagicValue = 0x63825363

staticprivate

Magic number value for the packet header.

Definition at line 50 of file DhcpClient.h.

Referenced by sendBootRequest().

◆ MaximumRetries

const Size DhcpClient::MaximumRetries = 25

staticprivate

Maximum number of retries to receive an IP address.

Definition at line 47 of file DhcpClient.h.

Referenced by exec().

◆ ReceiveTimeoutMs

const Size DhcpClient::ReceiveTimeoutMs = 500

staticprivate

Timeout in milliseconds to wait for packet receive.

Definition at line 53 of file DhcpClient.h.

Referenced by udpReceive().

◆ ServerPort

const u16 DhcpClient::ServerPort = 67

staticprivate

Server UDP port.

Definition at line 41 of file DhcpClient.h.

Referenced by udpSend().

The documentation for this class was generated from the following files:

bin/dhcpc/DhcpClient.h
bin/dhcpc/DhcpClient.cpp

Data Structures

Public Member Functions

Private Types

Private Member Functions

Private Attributes

Static Private Attributes

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ MessageType

◆ Operation

◆ Options

Constructor & Destructor Documentation

◆ DhcpClient()

◆ ~DhcpClient()

Member Function Documentation

◆ acknowledge()

◆ discover()

◆ exec()

◆ initialize()

◆ offer()

◆ receiveBootResponse()

◆ request()

◆ sendBootRequest()

◆ setIpAddress()

◆ udpReceive()

◆ udpSend()

Field Documentation

◆ ClientPort

◆ m_client

◆ m_etherAddress

◆ m_socket

◆ m_transactionId

◆ MagicValue

◆ MaximumRetries

◆ ReceiveTimeoutMs

◆ ServerPort