Base class for all address/prefix allocation algorithms. More...

#include <allocator.h>

Inheritance diagram for isc::dhcp::Allocator:

Public Types
enum	PrefixLenMatchType { PREFIX_LEN_EQUAL , PREFIX_LEN_LOWER , PREFIX_LEN_HIGHER }
	Type of preferred PD-pool prefix length selection criteria. More...

Public Member Functions
	Allocator (Lease::Type type, const WeakSubnetPtr &subnet)
	Constructor.

virtual	~Allocator ()
	Virtual destructor.

virtual std::string	getType () const =0
	Returns allocator type string.

void	initAfterConfigure ()
	Performs allocator initialization after server's reconfiguration.

virtual isc::asiolink::IOAddress	pickAddress (const ClientClasses &client_classes, const IdentifierBaseTypePtr &duid, const asiolink::IOAddress &hint)
	Picks an address.

virtual isc::asiolink::IOAddress	pickPrefix (const ClientClasses &client_classes, Pool6Ptr &pool, const IdentifierBaseTypePtr &duid, PrefixLenMatchType prefix_length_match, const asiolink::IOAddress &hint, uint8_t hint_prefix_length)
	Picks a delegated prefix.

Static Public Member Functions
static bool	isValidPrefixPool (Allocator::PrefixLenMatchType prefix_length_match, PoolPtr pool, uint8_t hint_prefix_length)
	Check if the pool matches the selection criteria relative to the provided hint prefix length.

Protected Member Functions
virtual void	initAfterConfigureInternal ()
	Allocator-specific initialization function.

Protected Attributes
bool	inited_
	Indicates if the allocator has been initialized.

std::mutex	mutex_
	The mutex to protect the allocated lease.

Lease::Type	pool_type_
	Defines pool type allocation.

WeakSubnetPtr	subnet_
	Weak pointer to the subnet owning the allocator.

SubnetID	subnet_id_
	ID of a subnet to which the allocator belongs.

Detailed Description

Base class for all address/prefix allocation algorithms.

This is an abstract class that should not be used directly, but rather specialized implementations should be used instead.

This class holds a weak pointer to the subnet owning it because it must not exist without the subnet. Also, it can't hold a shared pointer to the subnet because it would cause a circular dependency between the two.

Definition at line 57 of file allocator.h.

Member Enumeration Documentation

◆ PrefixLenMatchType

enum isc::dhcp::Allocator::PrefixLenMatchType

Type of preferred PD-pool prefix length selection criteria.

Enumerator
PREFIX_LEN_EQUAL
PREFIX_LEN_LOWER
PREFIX_LEN_HIGHER

Definition at line 61 of file allocator.h.

Constructor & Destructor Documentation

◆ Allocator()

isc::dhcp::Allocator::Allocator	(	Lease::Type	type,
		const WeakSubnetPtr &	subnet
	)

Constructor.

Specifies which type of leases this allocator will assign.

Parameters

type	specifies pool type (addresses, temporary addresses or prefixes).
subnet	weak pointer to the subnet owning the allocator.

Definition at line 17 of file allocator.cc.

References subnet_, and subnet_id_.

◆ ~Allocator()

isc::dhcp::Allocator::~Allocator ( )

virtual

Virtual destructor.

Removes all LeaseMgr callbacks it installed.

Definition at line 27 of file allocator.cc.

References isc::dhcp::LeaseMgrFactory::haveInstance(), isc::dhcp::LeaseMgrFactory::instance(), pool_type_, and subnet_id_.

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Member Function Documentation

◆ getType()

virtual std::string isc::dhcp::Allocator::getType ( ) const

pure virtual

Returns allocator type string.

Returns: allocator-specific type string.

Implemented in isc::dhcp::FreeLeaseQueueAllocator, isc::dhcp::IterativeAllocator, and isc::dhcp::RandomAllocator.

Referenced by initAfterConfigure().

◆ initAfterConfigure()

void isc::dhcp::Allocator::initAfterConfigure ( )

Performs allocator initialization after server's reconfiguration.

Some allocators install callbacks in the lease manager to keep track of the lease allocations. These callbacks may only be installed when the lease manager instance is available (i.e., when the server finishes the reconfiguration). Such callbacks can be installed in this function.

In this function, the allocators can also re-build their allocation states.

Definition at line 69 of file allocator.cc.

References isc::dhcp::DHCPSRV_CFGMGR_USE_ALLOCATOR, isc::dhcp::dhcpsrv_logger, getType(), initAfterConfigureInternal(), inited_, LOG_INFO, pool_type_, subnet_, and isc::dhcp::Lease::typeToText().

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◆ initAfterConfigureInternal()

virtual void isc::dhcp::Allocator::initAfterConfigureInternal ( )

inlineprotectedvirtual

Allocator-specific initialization function.

It is called by the initAfterConfigure and can be overridden in the derived allocators.

Definition at line 172 of file allocator.h.

Referenced by initAfterConfigure().

◆ isValidPrefixPool()

bool isc::dhcp::Allocator::isValidPrefixPool	(	Allocator::PrefixLenMatchType	prefix_length_match,
		PoolPtr	pool,
		uint8_t	hint_prefix_length
	)

static

Check if the pool matches the selection criteria relative to the provided hint prefix length.

Parameters

prefix_length_match	type which indicates the selection criteria for the pools relative to the provided hint prefix length.
pool	the pool checked for restricted delegated prefix length value.
hint_prefix_length	The hint prefix length that the client provided. The 0 value means that there is no hint and that any pool will suffice.

Definition at line 39 of file allocator.cc.

References PREFIX_LEN_EQUAL, PREFIX_LEN_HIGHER, and PREFIX_LEN_LOWER.

Referenced by isc::dhcp::Subnet::sumPoolCapacity().

◆ pickAddress()

virtual isc::asiolink::IOAddress isc::dhcp::Allocator::pickAddress	(	const ClientClasses &	client_classes,
		const IdentifierBaseTypePtr &	duid,
		const asiolink::IOAddress &	hint
	)

inlinevirtual

Picks an address.

This method returns one address from the available pools in the specified subnet. It should not check if the address is used or reserved - AllocEngine will check that and will call pickAddress again if necessary. The number of times this method is called will increase as the number of available leases will decrease.

Pools which are not allowed for client classes are skipped.

Parameters

client_classes	list of classes client belongs to.
duid	Client's DUID.
hint	Client's hint.

Returns: the next address.

Definition at line 102 of file allocator.h.

References mutex_.

◆ pickPrefix()

virtual isc::asiolink::IOAddress isc::dhcp::Allocator::pickPrefix	(	const ClientClasses &	client_classes,
		Pool6Ptr &	pool,
		const IdentifierBaseTypePtr &	duid,
		PrefixLenMatchType	prefix_length_match,
		const asiolink::IOAddress &	hint,
		uint8_t	hint_prefix_length
	)

inlinevirtual

Picks a delegated prefix.

This method returns one prefix from the available pools in the specified subnet. It should not check if the prefix is used or reserved - AllocEngine will check that and will call pickPrefix again if necessary. The number of times this method is called will increase as the number of available leases will decrease.

Pools which are not allowed for client classes are skipped.

Parameters

client_classes	list of classes client belongs to.
pool	the selected pool satisfying all required conditions.
duid	Client's DUID.
prefix_length_match	type which indicates the selection criteria for the pools relative to the provided hint prefix length.
hint	Client's hint.
hint_prefix_length	the hint prefix length that the client provided. The 0 value means that there is no hint and that any pool will suffice.

Returns: the next prefix.

Definition at line 131 of file allocator.h.

References mutex_.

Member Data Documentation

◆ inited_

bool isc::dhcp::Allocator::inited_

protected

Indicates if the allocator has been initialized.

It is set to true when initAfterConfigure has been called. It prevents initializing the allocator several times.

Definition at line 223 of file allocator.h.

Referenced by initAfterConfigure().

◆ mutex_

std::mutex isc::dhcp::Allocator::mutex_

protected

The mutex to protect the allocated lease.

Definition at line 235 of file allocator.h.

Referenced by pickAddress(), and pickPrefix().

◆ pool_type_

Lease::Type isc::dhcp::Allocator::pool_type_

protected

Defines pool type allocation.

Definition at line 226 of file allocator.h.

Referenced by ~Allocator(), and initAfterConfigure().

◆ subnet_

WeakSubnetPtr isc::dhcp::Allocator::subnet_

protected

Weak pointer to the subnet owning the allocator.

Definition at line 232 of file allocator.h.

Referenced by Allocator(), and initAfterConfigure().

◆ subnet_id_

SubnetID isc::dhcp::Allocator::subnet_id_

protected

ID of a subnet to which the allocator belongs.

Definition at line 229 of file allocator.h.

Referenced by Allocator(), and ~Allocator().

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

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ PrefixLenMatchType

Constructor & Destructor Documentation

◆ Allocator()

◆ ~Allocator()

Member Function Documentation

◆ getType()

◆ initAfterConfigure()

◆ initAfterConfigureInternal()

◆ isValidPrefixPool()

◆ pickAddress()

◆ pickPrefix()

Member Data Documentation

◆ inited_

◆ mutex_

◆ pool_type_

◆ subnet_

◆ subnet_id_