Token that represents sub-options in DHCPv4 and DHCPv6. More...

#include <token.h>

Inheritance diagram for isc::dhcp::TokenSubOption:

Public Member Functions
	TokenSubOption (const uint16_t option_code, const uint16_t sub_option_code, const RepresentationType &rep_type)
	Constructor that takes an option and sub-option codes as parameter.

virtual unsigned	evaluate (Pkt &pkt, ValueStack &values)
	This is a method for evaluating a packet.

uint16_t	getSubCode () const
	Returns sub-option-code.

Public Member Functions inherited from isc::dhcp::TokenOption
	TokenOption (const uint16_t option_code, const RepresentationType &rep_type)
	Constructor that takes an option code as a parameter.

uint16_t	getCode () const
	Returns option-code.

RepresentationType	getRepresentation () const
	Returns representation-type.

Public Member Functions inherited from isc::dhcp::Token
virtual	~Token ()
	Virtual destructor.

virtual unsigned	getLabel () const
	Return the label of this token.

Protected Member Functions
virtual OptionPtr	getSubOption (const OptionPtr &parent)
	Attempts to retrieve a sub-option.

Protected Member Functions inherited from isc::dhcp::TokenOption
virtual OptionPtr	getOption (Pkt &pkt)
	Attempts to retrieve an option.

virtual std::string	pushFailure (ValueStack &values)
	Auxiliary method that puts string representing a failure.

Protected Attributes
uint16_t	sub_option_code_
	Code of the sub-option to be extracted.

Protected Attributes inherited from isc::dhcp::TokenOption
uint16_t	option_code_
	Code of the option to be extracted.

RepresentationType	representation_type_
	Representation type.

Additional Inherited Members
Public Types inherited from isc::dhcp::TokenOption
enum	RepresentationType { TEXTUAL , HEXADECIMAL , EXISTS }
	Token representation type. More...

Static Public Member Functions inherited from isc::dhcp::Token
static bool	toBool (std::string value)
	Coverts a (string) value to a boolean.

Detailed Description

Token that represents sub-options in DHCPv4 and DHCPv6.

It covers any options which encapsulate sub-options, for instance dhcp-agent-options (82, DHCPv4) or rsoo (66, DHCPv6). This class is derived from TokenOption and leverages its ability to operate on sub-options. It also adds additional capabilities.

Note: TokenSubOption virtually derives TokenOption because both classes are inherited together in more complex classes in other parts of the code. This makes the base class TokenOption to exist only once in such complex classes.

It can represent the following expressions: option[149].exists - check if option 149 exists option[149].option[1].exists - check if suboption 1 exists in the option 149 option[149].option[1].hex - return content of suboption 1 for option 149

Definition at line 1324 of file token.h.

Constructor & Destructor Documentation

◆ TokenSubOption()

isc::dhcp::TokenSubOption::TokenSubOption	(	const uint16_t	option_code,
		const uint16_t	sub_option_code,
		const RepresentationType &	rep_type )

inline

Constructor that takes an option and sub-option codes as parameter.

Note: Does not define its own representation type: simply use the TokenOption::RepresentationType

Note: There is no constructor that takes names.

Parameters

option_code	code of the parent option.
sub_option_code	code of the sub-option to be represented.
rep_type	Token representation type.

Definition at line 1337 of file token.h.

Member Function Documentation

◆ evaluate()

unsigned TokenSubOption::evaluate	(	Pkt &	pkt,
		ValueStack &	values )

virtual

This is a method for evaluating a packet.

This token represents a value of the sub-option, so this method attempts to extract the parent option from the packet and when it succeeds to extract the sub-option from the option and its value on the stack. If the parent option or the sub-option is not there, an empty string ("") is put on the stack.

Parameters

pkt	specified parent option will be extracted from this packet
values	value of the sub-option will be pushed here (or "")

Returns: 0 which means evaluate next token if any.

Reimplemented from isc::dhcp::TokenOption.

Definition at line 1416 of file token.cc.

References isc::dhcp::EVAL_DBG_STACK, isc::dhcp::EVAL_DEBUG_SUB_OPTION, isc::dhcp::EVAL_DEBUG_SUB_OPTION_NO_OPTION, isc::dhcp::eval_logger, isc::dhcp::TokenOption::EXISTS, isc::dhcp::Pkt::getLabel(), isc::dhcp::TokenOption::getOption(), getSubOption(), isc::dhcp::TokenOption::HEXADECIMAL, LOG_DEBUG, isc::dhcp::TokenOption::option_code_, isc::dhcp::TokenOption::representation_type_, sub_option_code_, and isc::dhcp::TokenOption::TEXTUAL.

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◆ getSubCode()

uint16_t isc::dhcp::TokenSubOption::getSubCode ( ) const

inline

Returns sub-option-code.

This method is used in testing to determine if the parser had instantiated TokenSubOption with correct parameters.

Returns: option-code of the sub-option this token expects to extract.

Definition at line 1362 of file token.h.

References sub_option_code_.

◆ getSubOption()

OptionPtr TokenSubOption::getSubOption ( const OptionPtr & parent )

protectedvirtual

Attempts to retrieve a sub-option.

Parameters

parent the sub-option will be retrieved from here

Returns: sub-option instance (or NULL if not found)

Definition at line 1408 of file token.cc.

References sub_option_code_.

Referenced by evaluate().

Member Data Documentation

◆ sub_option_code_

uint16_t isc::dhcp::TokenSubOption::sub_option_code_

protected

Code of the sub-option to be extracted.

Definition at line 1373 of file token.h.

Referenced by evaluate(), getSubCode(), and getSubOption().

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

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TokenSubOption()

Member Function Documentation

◆ evaluate()

◆ getSubCode()

◆ getSubOption()

Member Data Documentation

◆ sub_option_code_