Structure that holds a lease for IPv4 address. More...

#include <lease.h>

Inheritance diagram for isc::dhcp::Lease4:

Public Member Functions
	Lease4 ()
	Default constructor.

	Lease4 (const isc::asiolink::IOAddress &addr, const HWAddrPtr &hwaddr, const uint8_t *clientid, size_t clientid_len, uint32_t valid_lft, time_t cltt, uint32_t subnet_id, const bool fqdn_fwd=false, const bool fqdn_rev=false, const std::string &hostname="")
	Constructor.

	Lease4 (const isc::asiolink::IOAddress &address, const HWAddrPtr &hw_address, const ClientIdPtr &client_id, const uint32_t valid_lifetime, const time_t cltt, const SubnetID subnet_id, const bool fqdn_fwd=false, const bool fqdn_rev=false, const std::string &hostname="")
	Constructor.

bool	belongsToClient (const HWAddrPtr &hw_address, const ClientIdPtr &client_id) const
	Check if the lease belongs to the client with the given identifiers.

void	decline (uint32_t probation_period)
	Sets IPv4 lease to declined state.

const std::vector< uint8_t > &	getClientIdVector () const
	Returns a client identifier.

virtual Lease::Type	getType () const
	Returns Lease type.

bool	operator!= (const Lease4 &other) const
	Compare two leases for inequality.

bool	operator== (const Lease4 &other) const
	Compare two leases for equality.

virtual isc::data::ElementPtr	toElement () const
	Return the JSON representation of a lease.

virtual std::string	toText () const
	Convert lease to printable form.

Public Member Functions inherited from isc::dhcp::Lease
	Lease (const isc::asiolink::IOAddress &addr, uint32_t valid_lft, SubnetID subnet_id, time_t cltt, const bool fqdn_fwd, const bool fqdn_rev, const std::string &hostname, const HWAddrPtr &hwaddr)
	Constructor.

virtual	~Lease ()
	Destructor.

bool	expired () const
	returns true if the lease is expired

bool	stateExpiredReclaimed () const
	Indicates if the lease is in the "expired-reclaimed" state.

bool	stateDeclined () const
	Indicates if the lease is in the "declined" state.

bool	hasIdenticalFqdn (const Lease &other) const
	Returns true if the other lease has equal FQDN data.

const std::vector< uint8_t > &	getHWAddrVector () const
	Returns raw (as vector) hardware address.

int64_t	getExpirationTime () const
	Returns lease expiration time.

void	updateCurrentExpirationTime ()
	Update lease current expiration time with new value, so that additional operations can be done without performing extra read from the database.

Public Member Functions inherited from isc::data::UserContext
void	contextToElement (data::ElementPtr map) const
	Merge unparse a user_context object.

data::ConstElementPtr	getContext () const
	Returns const pointer to the user context.

void	setContext (const data::ConstElementPtr &ctx)
	Sets user context.

Public Member Functions inherited from isc::data::CfgToElement
virtual	~CfgToElement ()
	Destructor.

Static Public Member Functions
static Lease4Ptr	fromElement (const data::ConstElementPtr &element)
	Returns pointer to the IPv4 lease created from JSON representation.

static std::string	statesToText (const uint32_t state)
	Returns name of the lease states specific to DHCPv4.

Static Public Member Functions inherited from isc::dhcp::Lease
static std::string	lifetimeToText (uint32_t lifetime)
	Print lifetime.

static Type	textToType (const std::string &text)
	Converts type name to the actual type.

static std::string	typeToText (Type type)
	returns text representation of a lease type

static std::string	basicStatesToText (const uint32_t state)
	Returns name(s) of the basic lease state(s).

static void	syncCurrentExpirationTime (const Lease &from, Lease &to)
	Sync lease current expiration time with new value from another lease, so that additional operations can be done without performing extra read from the database.

Static Public Member Functions inherited from isc::data::UserContext
static data::ElementPtr	toElement (data::ConstElementPtr map)
	Copy an Element map.

Public Attributes
ClientIdPtr	client_id_
	Client identifier.

std::vector< uint8_t >	relay_id_
	Relay identifier for Bulk Lease Query.

std::vector< uint8_t >	remote_id_
	Remote identifier for Bulk Lease Query.

Public Attributes inherited from isc::dhcp::Lease
isc::asiolink::IOAddress	addr_
	IPv4 ot IPv6 address.

uint32_t	valid_lft_
	Valid lifetime.

uint32_t	current_valid_lft_
	Current valid lifetime.

uint32_t	reuseable_valid_lft_
	Remaining valid lifetime.

time_t	cltt_
	Client last transmission time.

time_t	current_cltt_
	Current client last transmission time.

SubnetID	subnet_id_
	Subnet identifier.

uint32_t	pool_id_
	The pool id.

std::string	hostname_
	Client hostname.

bool	fqdn_fwd_
	Forward zone updated?

bool	fqdn_rev_
	Reverse zone updated?

HWAddrPtr	hwaddr_
	Client's MAC/hardware address.

uint32_t	state_
	Holds the lease state(s).

Additional Inherited Members
Public Types inherited from isc::dhcp::Lease
enum	Type { TYPE_NA = 0 , TYPE_TA = 1 , TYPE_PD = 2 , TYPE_V4 = 3 }
	Type of lease or pool. More...

Static Public Attributes inherited from isc::dhcp::Lease
static const uint32_t	INFINITY_LFT = 0xffffffff
	Infinity (means static, i.e. never expire)

static const uint32_t	STATE_DEFAULT = 0
	A lease in the default state.

static const uint32_t	STATE_DECLINED = 1
	Declined lease.

static const uint32_t	STATE_EXPIRED_RECLAIMED = 2
	Expired and reclaimed lease.

static const uint32_t	STATE_RELEASED = 3
	Released lease held in the database for lease affinity.

Static Protected Member Functions inherited from isc::dhcp::Lease
static void	fromElementCommon (const LeasePtr &lease, const data::ConstElementPtr &element)
	Sets common (for v4 and v6) properties of the lease object.

Protected Attributes inherited from isc::data::UserContext
data::ConstElementPtr	user_context_
	Pointer to the user context (may be NULL)

Detailed Description

Structure that holds a lease for IPv4 address.

For performance reasons it is a simple structure, not a class. If we chose make it a class, all fields would have to made private and getters/setters would be required. As this is a critical part of the code that will be used extensively, direct access is warranted.

Definition at line 303 of file lease.h.

Constructor & Destructor Documentation

◆ Lease4() [1/3]

isc::dhcp::Lease4::Lease4	(	const isc::asiolink::IOAddress &	addr,
		const HWAddrPtr &	hwaddr,
		const uint8_t *	clientid,
		size_t	clientid_len,
		uint32_t	valid_lft,
		time_t	cltt,
		uint32_t	subnet_id,
		const bool	fqdn_fwd = false,
		const bool	fqdn_rev = false,
		const std::string &	hostname = "" )

inline

Constructor.

Parameters

addr	IPv4 address.
hwaddr	A pointer to HWAddr structure
clientid	Client identification buffer
clientid_len	Length of client identification buffer
valid_lft	Lifetime of the lease
cltt	Client last transmission time
subnet_id	Subnet identification
fqdn_fwd	If true, forward DNS update is performed for a lease.
fqdn_rev	If true, reverse DNS update is performed for a lease.
hostname	FQDN of the client which gets the lease.

Definition at line 323 of file lease.h.

References client_id_.

◆ Lease4() [2/3]

isc::dhcp::Lease4::Lease4	(	const isc::asiolink::IOAddress &	address,
		const HWAddrPtr &	hw_address,
		const ClientIdPtr &	client_id,
		const uint32_t	valid_lifetime,
		const time_t	cltt,
		const SubnetID	subnet_id,
		const bool	fqdn_fwd = false,
		const bool	fqdn_rev = false,
		const std::string &	hostname = "" )

Constructor.

Parameters

address	IPv4 address.
hw_address	Pointer to client's HW address.
client_id	pointer to the client id structure.
valid_lifetime	Valid lifetime value.
cltt	Timestamp when the lease is acquired, renewed.
subnet_id	Subnet identifier.
fqdn_fwd	Forward DNS update performed.
fqdn_rev	Reverse DNS update performed.
hostname	Client's name for the DNS update..

Definition at line 318 of file lease.cc.

◆ Lease4() [3/3]

isc::dhcp::Lease4::Lease4 ( )

Default constructor.

Initialize fields that don't have a default constructor.

Definition at line 332 of file lease.cc.

Referenced by fromElement().

Member Function Documentation

◆ belongsToClient()

bool isc::dhcp::Lease4::belongsToClient	(	const HWAddrPtr &	hw_address,
		const ClientIdPtr &	client_id ) const

Check if the lease belongs to the client with the given identifiers.

This method checks if the lease belongs to the client using the specified HW address and/or client identifier. Note that any of the pointers passed to this method may be set to null, in which case they are treated as unspecified and are not used for matching the client with the lease.

According to the DHCPv4 specifications, the client identifier takes precedence over the HW address when identifying the lease for the client on the server side. In particular, the RFC4361 introduces the use of DUID for DHCPv4 which should be a stable identifier for the client. The use of stable identifier allows for the correlation of the DHCPv4 and DHCPv6 clients in the dual stack networks. It also allows for allocating the same lease to the client which hardware (and thus MAC address) has changed.

By default, Kea respects the precedence of the client identifier over MAC address and when this method finds the match of the client identifier with the client identifier stored in the lease, it will treat the lease as the lease of this client, even when the HW address doesn't match.

The HW address is used for matching the client with the lease only when the lease is not associated with any client identifier (client identifier for the lease is null) or when the client identifier parameter passed to this method is null. This facilitates the following cases:

client didn't generate client identifier and is only using the chaddr field to identify itself.
server's administrator configured the server to NOT match client identifiers, the client obtained the new lease, and the administrator reconfigured the server to match the client identifiers. The client is trying to renew its lease and both the client identifier and HW address is used for matching the lease which doesn't have the record of the client identifier.
client obtained the lease using the HW address and client identifier, the server's administrator configured the server to NOT match the client identifiers, and the client returns to renew the lease. This time, the lease has a record of both client identifier and the HW address but only the HW address is used for matching the client to the lease.

Note that the typical case when the server's administrator may want to disable matching the client identifier passed in the client's message is when the client is performing multi-stage boot. In such case, the client identifiers may change on various stages of the boot, but the HW address will remain stable. The server's administrator prefers using the HW address for client identification in this case.

It may also be useful to disable matching client identifiers to mitigate the problem of broken client implementations which generate new client identifiers every time they connect to the network.

Parameters

hw_address	Pointer to the HW address of the client.
client_id	Pointer to the client identifier structure.

Returns: true if the lease belongs to the client using the specified hardware address and/or client identifier.

Definition at line 360 of file lease.cc.

References client_id_, isc::util::equalValues(), and isc::dhcp::Lease::hwaddr_.

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◆ decline()

void isc::dhcp::Lease4::decline ( uint32_t probation_period )

virtual

Sets IPv4 lease to declined state.

See Lease::decline for detailed description.

Parameters

probation_period valid lifetime will be set to this value

Implements isc::dhcp::Lease.

Definition at line 377 of file lease.cc.

References client_id_, isc::dhcp::Lease::cltt_, isc::dhcp::Lease::fqdn_fwd_, isc::dhcp::Lease::fqdn_rev_, isc::dhcp::Lease::hostname_, isc::dhcp::Lease::hwaddr_, isc::dhcp::Lease::state_, isc::dhcp::Lease::STATE_DECLINED, and isc::dhcp::Lease::valid_lft_.

◆ fromElement()

Lease4Ptr isc::dhcp::Lease4::fromElement ( const data::ConstElementPtr & element )

static

Returns pointer to the IPv4 lease created from JSON representation.

Parameters

element pointer to the data element object to be parsed.

Returns: Pointer to the created lease.

Definition at line 417 of file lease.cc.

References Lease4(), isc::dhcp::Lease::fromElementCommon(), isc::dhcp::ClientId::fromText(), isc_throw, and isc::data::Element::string.

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◆ getClientIdVector()

const std::vector< uint8_t > & isc::dhcp::Lease4::getClientIdVector ( ) const

Returns a client identifier.

Warning: Since the function returns the reference to a vector (not a copy), the returned object should be used with caution because it will remain valid only for the period of time when an object which returned it exists.

Returns: A reference to a vector holding client identifier, or an empty vector if client identifier is NULL.

Definition at line 341 of file lease.cc.

References client_id_.

◆ getType()

virtual Lease::Type isc::dhcp::Lease4::getType ( ) const

inlinevirtual

Returns Lease type.

Since Lease does not define a member for lease type, we implement this so we don't store the same value in a billion v4 lease instances.

Returns: Lease::TYPE_V4

Implements isc::dhcp::Lease.

Definition at line 368 of file lease.h.

References isc::dhcp::Lease::TYPE_V4.

◆ operator!=()

bool isc::dhcp::Lease4::operator!= ( const Lease4 & other ) const

inline

Compare two leases for inequality.

Parameters

other lease6 object with which to compare

Definition at line 464 of file lease.h.

◆ operator==()

bool isc::dhcp::Lease4::operator== ( const Lease4 & other ) const

Compare two leases for equality.

Parameters

other lease6 object with which to compare

Definition at line 585 of file lease.cc.

References isc::dhcp::Lease::addr_, client_id_, isc::dhcp::Lease::cltt_, isc::dhcp::Lease::current_cltt_, isc::dhcp::Lease::current_valid_lft_, isc::dhcp::Lease::fqdn_fwd_, isc::dhcp::Lease::fqdn_rev_, isc::data::UserContext::getContext(), isc::dhcp::Lease::hostname_, isc::dhcp::Lease::hwaddr_, isc::util::nullOrEqualValues(), isc::dhcp::Lease::pool_id_, isc::dhcp::Lease::reuseable_valid_lft_, isc::dhcp::Lease::state_, isc::dhcp::Lease::subnet_id_, and isc::dhcp::Lease::valid_lft_.

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◆ statesToText()

std::string isc::dhcp::Lease4::statesToText ( const uint32_t state )

static

Returns name of the lease states specific to DHCPv4.

Todo: Currently it simply returns common states for DHCPv4 and DHCPv6. This method will have to be extended to handle DHCPv4 specific states when they are defined.

Parameters

state Numeric value holding lease states.

Returns: Comma separated list of lease state names.

Definition at line 336 of file lease.cc.

References isc::dhcp::Lease::basicStatesToText().

Referenced by toText().

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◆ toElement()

isc::data::ElementPtr isc::dhcp::Lease4::toElement ( ) const

virtual

Return the JSON representation of a lease.

Implements isc::data::CfgToElement.

Definition at line 389 of file lease.cc.

References isc::dhcp::Lease::addr_, client_id_, isc::dhcp::Lease::cltt_, isc::data::UserContext::contextToElement(), isc::data::Element::create(), isc::data::Element::createMap(), isc::dhcp::Lease::fqdn_fwd_, isc::dhcp::Lease::fqdn_rev_, isc::dhcp::Lease::hostname_, isc::dhcp::Lease::hwaddr_, isc::dhcp::Lease::pool_id_, isc::dhcp::Lease::state_, isc::dhcp::Lease::subnet_id_, isc::asiolink::IOAddress::toText(), and isc::dhcp::Lease::valid_lft_.

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◆ toText()

std::string isc::dhcp::Lease4::toText ( ) const

virtual

Convert lease to printable form.

Returns: Textual representation of lease data

Implements isc::dhcp::Lease.

Definition at line 561 of file lease.cc.

References isc::dhcp::Lease::addr_, client_id_, isc::dhcp::Lease::cltt_, isc::util::str::dumpAsHex(), isc::data::UserContext::getContext(), isc::dhcp::Lease::hwaddr_, isc::dhcp::Lease::lifetimeToText(), isc::dhcp::Lease::pool_id_, relay_id_, remote_id_, isc::dhcp::Lease::state_, statesToText(), isc::dhcp::Lease::subnet_id_, and isc::dhcp::Lease::valid_lft_.

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Member Data Documentation

◆ client_id_

ClientIdPtr isc::dhcp::Lease4::client_id_

Client identifier.

Todo: Should this be a pointer to a client ID or the ID itself? Compare with the DUID in the Lease6 structure.

Definition at line 309 of file lease.h.

Referenced by Lease4(), belongsToClient(), decline(), getClientIdVector(), operator==(), toElement(), and toText().

◆ relay_id_

std::vector<uint8_t> isc::dhcp::Lease4::relay_id_

Relay identifier for Bulk Lease Query.

Definition at line 496 of file lease.h.

Referenced by toText().

◆ remote_id_

std::vector<uint8_t> isc::dhcp::Lease4::remote_id_

Remote identifier for Bulk Lease Query.

Todo: : Add DHCPv4 failover related fields here

Definition at line 493 of file lease.h.

Referenced by toText().

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

Public Member Functions

Static Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Lease4() [1/3]

◆ Lease4() [2/3]

◆ Lease4() [3/3]

Member Function Documentation

◆ belongsToClient()

◆ decline()

◆ fromElement()

◆ getClientIdVector()

◆ getType()

◆ operator!=()

◆ operator==()

◆ statesToText()

◆ toElement()

◆ toText()

Member Data Documentation

◆ client_id_

◆ relay_id_

◆ remote_id_