Utility class for option data types. More...

#include <option_data_types.h>

Static Public Member Functions
static OptionDataType	getDataType (const std::string &data_type)
	Return option data type from its name.

static int	getDataTypeLen (const OptionDataType data_type)
	Get data type buffer length.

static const std::string &	getDataTypeName (const OptionDataType data_type)
	Return option data type name from the data type enumerator.

static unsigned int	getLabelCount (const std::string &text_name)
	Return the number of labels in the Name.

static OpaqueDataTuple::LengthFieldType	getTupleLenFieldType (Option::Universe u)
	Returns Length Field Type for a tuple.

static asiolink::IOAddress	readAddress (const std::vector< uint8_t > &buf, const short family)
	Read IPv4 or IPv6 address from a buffer.

static bool	readBool (const std::vector< uint8_t > &buf)
	Read boolean value from a buffer.

static std::string	readFqdn (const std::vector< uint8_t > &buf)
	Read FQDN from a buffer as a string value.

template<typename T >
static T	readInt (const std::vector< uint8_t > &buf)
	Read integer value from a buffer.

static PrefixTuple	readPrefix (const std::vector< uint8_t > &buf)
	Read prefix from a buffer.

static PSIDTuple	readPsid (const std::vector< uint8_t > &buf)
	Read PSID length / value tuple from a buffer.

static std::string	readString (const std::vector< uint8_t > &buf)
	Read string value from a buffer.

static void	readTuple (const std::vector< uint8_t > &buf, OpaqueDataTuple &tuple)
	Read length and string tuple from a buffer.

static std::string	readTuple (const std::vector< uint8_t > &buf, OpaqueDataTuple::LengthFieldType lengthfieldtype)
	Read length and string tuple from a buffer.

static void	writeAddress (const asiolink::IOAddress &address, std::vector< uint8_t > &buf)
	Append IPv4 or IPv6 address to a buffer.

static void	writeBinary (const std::string &hex_str, std::vector< uint8_t > &buf)
	Append hex-encoded binary values to a buffer.

static void	writeBool (const bool value, std::vector< uint8_t > &buf)
	Append boolean value into a buffer.

static void	writeFqdn (const std::string &fqdn, std::vector< uint8_t > &buf, const bool downcase=false)
	Append FQDN into a buffer.

template<typename T >
static void	writeInt (const T value, std::vector< uint8_t > &buf)
	Append integer or unsigned integer value to a buffer.

static void	writePrefix (const PrefixLen &prefix_len, const asiolink::IOAddress &prefix, std::vector< uint8_t > &buf)
	Append prefix into a buffer.

static void	writePsid (const PSIDLen &psid_len, const PSID &psid, std::vector< uint8_t > &buf)
	Append PSID length/value into a buffer.

static void	writeString (const std::string &value, std::vector< uint8_t > &buf)
	Write UTF8-encoded string into a buffer.

static void	writeTuple (const OpaqueDataTuple &tuple, std::vector< uint8_t > &buf)
	Append length and string tuple to a buffer.

static void	writeTuple (const std::string &value, OpaqueDataTuple::LengthFieldType lengthfieldtype, std::vector< uint8_t > &buf)
	Append length and string tuple to a buffer.

Detailed Description

Utility class for option data types.

This class provides a set of utility functions to operate on supported DHCP option data types. It includes conversion between enumerator values representing data types and data type names. It also includes a set of functions that write data into option buffers and read data from option buffers. The data being written and read are converted from/to actual data types.

Note: This is a singleton class but it can be accessed via static methods only.

Definition at line 330 of file option_data_types.h.

Member Function Documentation

◆ getDataType()

OptionDataType isc::dhcp::OptionDataTypeUtil::getDataType ( const std::string & data_type )

static

Return option data type from its name.

Parameters

data_type data type name.

Returns: option data type.

Definition at line 83 of file option_data_types.cc.

Referenced by isc::dhcp::OptionDefinition::OptionDefinition(), and isc::dhcp::OptionDefinition::addRecordField().

◆ getDataTypeLen()

int isc::dhcp::OptionDataTypeUtil::getDataTypeLen ( const OptionDataType data_type )

static

Get data type buffer length.

This function returns the size of a particular data type. Values returned by this function correspond to the data type sizes defined in OptionDataTypeTraits (IPV4_ADDRESS_TYPE and IPV6_ADDRESS_TYPE are exceptions here) so they rather indicate the fixed length of the data being written into the buffer, not the size of the particular data type. Thus for data types such as string, binary etc. for which the buffer length can't be determined this function returns 0. In addition, this function returns the data sizes for IPV4_ADDRESS_TYPE and IPV6_ADDRESS_TYPE as their buffer representations have fixed data lengths: 4 and 16 respectively.

Parameters

data_type data type which size is to be returned.

Returns: data type size or zero for variable length types.

Definition at line 98 of file option_data_types.cc.

References isc::dhcp::OPT_BOOLEAN_TYPE, isc::dhcp::OPT_INT16_TYPE, isc::dhcp::OPT_INT32_TYPE, isc::dhcp::OPT_INT8_TYPE, isc::dhcp::OPT_IPV4_ADDRESS_TYPE, isc::dhcp::OPT_IPV6_ADDRESS_TYPE, isc::dhcp::OPT_PSID_TYPE, isc::dhcp::OPT_UINT16_TYPE, isc::dhcp::OPT_UINT32_TYPE, and isc::dhcp::OPT_UINT8_TYPE.

◆ getDataTypeName()

const std::string & isc::dhcp::OptionDataTypeUtil::getDataTypeName ( const OptionDataType data_type )

static

Return option data type name from the data type enumerator.

Parameters

data_type option data type.

Returns: option data type name.

Definition at line 129 of file option_data_types.cc.

Referenced by isc::dhcp::OptionDefinition::addRecordField(), isc::dhcp::CfgOptionDef::toElementWithMetadata(), isc::dhcp::OptionInt< T >::toText(), and isc::dhcp::OptionIntArray< T >::toText().

◆ getLabelCount()

unsigned int isc::dhcp::OptionDataTypeUtil::getLabelCount ( const std::string & text_name )

static

Return the number of labels in the Name.

If the specified name is empty the 0 is returned.

Parameters

text_name A text representation of the name.

Returns: A number of labels in the provided name or 0 if the name string is empty.

Exceptions

isc::dhcp::BadDataTypeCast if provided name is malformed.

Definition at line 376 of file option_data_types.cc.

References isc::dns::Name::getLabelCount(), isc_throw, and isc::Exception::what().

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◆ getTupleLenFieldType()

OpaqueDataTuple::LengthFieldType isc::dhcp::OptionDataTypeUtil::getTupleLenFieldType ( Option::Universe u )

static

Returns Length Field Type for a tuple.

Returns Length Field Type for a tuple basing on the given Option v4/v6 Universe.

Parameters

u	specifies universe (V4 or V6)

Returns: By default 1 octet Length Field Type for V4 option or 2 octets Length Field Type for V6 option

Definition at line 197 of file option_data_types.cc.

References isc::dhcp::OpaqueDataTuple::LENGTH_1_BYTE, isc::dhcp::OpaqueDataTuple::LENGTH_2_BYTES, and isc::dhcp::Option::V4.

Referenced by isc::dhcp::OptionOpaqueDataTuples::OptionOpaqueDataTuples(), isc::dhcp::OptionCustom::addArrayDataField(), isc::dhcp::OptionVendorClass::addTuple(), isc::dhcp::OptionCustom::readTuple(), isc::dhcp::OptionVendorClass::setTuple(), isc::dhcp::OptionVendorClass::unpack(), isc::dhcp::DnrInstance::unpackAdn(), and isc::dhcp::OptionCustom::writeTuple().

◆ readAddress()

asiolink::IOAddress isc::dhcp::OptionDataTypeUtil::readAddress	(	const std::vector< uint8_t > &	buf,
		const short	family
	)

static

Read IPv4 or IPv6 address from a buffer.

Parameters

buf	input buffer.
family	address family: AF_INET or AF_INET6.

Exceptions

isc::dhcp::BadDataTypeCast when the data being read is truncated.

Returns: address being read.

Definition at line 150 of file option_data_types.cc.

References isc::asiolink::IOAddress::fromBytes(), and isc_throw.

Referenced by isc::dhcp::OptionCustom::readAddress().

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◆ readBool()

bool isc::dhcp::OptionDataTypeUtil::readBool ( const std::vector< uint8_t > & buf )

static

Read boolean value from a buffer.

Parameters

buf	input buffer.

Exceptions

isc::dhcp::BadDataTypeCast when the data being read is truncated or the value is invalid (neither 1 nor 0).

Returns: boolean value read from a buffer.

Definition at line 317 of file option_data_types.cc.

References isc_throw.

Referenced by isc::dhcp::OptionCustom::readBoolean().

◆ readFqdn()

std::string isc::dhcp::OptionDataTypeUtil::readFqdn ( const std::vector< uint8_t > & buf )

static

Read FQDN from a buffer as a string value.

The format of an FQDN within a buffer complies with RFC1035, section 3.1.

Parameters

buf	input buffer holding a FQDN.

Exceptions

BadDataTypeCast if a FQDN stored within a buffer is invalid (e.g. empty, contains invalid characters, truncated).

Returns: fully qualified domain name in a text form.

Definition at line 338 of file option_data_types.cc.

References isc_throw, isc::dns::Name::toText(), and isc::Exception::what().

Referenced by isc::dhcp::OptionCustom::readFqdn().

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◆ readInt()

template<typename T >

static T isc::dhcp::OptionDataTypeUtil::readInt ( const std::vector< uint8_t > & buf )

inlinestatic

Read integer value from a buffer.

Parameters

buf	input buffer.

Template Parameters

integer type of the returned value.

Exceptions

isc::dhcp::BadDataTypeCast when the data in the buffer is truncated.

Returns: integer value being read.

Definition at line 461 of file option_data_types.h.

References isc_throw, isc::util::readUint16(), and isc::util::readUint32().

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◆ readPrefix()

PrefixTuple isc::dhcp::OptionDataTypeUtil::readPrefix ( const std::vector< uint8_t > & buf )

static

Read prefix from a buffer.

This method reads prefix length and a prefix value from a buffer. The prefix value has variable length and this length is determined from the first byte of the buffer. If the length is not divisible by 8, the prefix is padded with zeros to the next byte boundary.

Parameters

buf	input buffer holding a prefix length / prefix tuple.

Returns: Prefix length and value.

Definition at line 394 of file option_data_types.cc.

References isc::dhcp::PrefixLen::asUint8(), isc::dhcp::PrefixLen::asUnsigned(), isc::asiolink::IOAddress::fromBytes(), isc::asiolink::IOAddress::IPV6_ZERO_ADDRESS(), isc_throw, and isc::Exception::what().

Referenced by isc::dhcp::OptionCustom::readPrefix().

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◆ readPsid()

PSIDTuple isc::dhcp::OptionDataTypeUtil::readPsid ( const std::vector< uint8_t > & buf )

static

Read PSID length / value tuple from a buffer.

This method reads three bytes from a buffer. The first byte holds a PSID length value. The remaining two bytes contain a zero padded PSID value.

Returns: PSID length / value tuple.

Exceptions

isc::dhcp::BadDataTypeCast if PSID length or value held in the buffer is incorrect or the buffer is truncated.

Definition at line 528 of file option_data_types.cc.

References isc_throw, and isc::util::readUint16().

Referenced by isc::dhcp::OptionCustom::readPsid().

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◆ readString()

std::string isc::dhcp::OptionDataTypeUtil::readString ( const std::vector< uint8_t > & buf )

static

Read string value from a buffer.

To be compliant with RFC 2132, Sec. 2, trailing NULLs are trimmed.

Parameters

buf	input buffer.

Returns: string value being read.

Exceptions

isc::dhcp::OutOfRange is the payload contains only NULLs.

Definition at line 594 of file option_data_types.cc.

References isc_throw, and isc::util::str::seekTrimmed().

Referenced by isc::dhcp::OptionCustom::readString().

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◆ readTuple() [1/2]

void isc::dhcp::OptionDataTypeUtil::readTuple	(	const std::vector< uint8_t > &	buf,
		OpaqueDataTuple &	tuple
	)

static

Read length and string tuple from a buffer.

Parameters

buf	input buffer.
tuple	reference of the tuple to read into

Exceptions

isc::dhcp::BadDataTypeCast when the data being read is truncated.

Definition at line 247 of file option_data_types.cc.

References isc_throw, isc::dhcp::OpaqueDataTuple::unpack(), and isc::Exception::what().

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◆ readTuple() [2/2]

std::string isc::dhcp::OptionDataTypeUtil::readTuple	(	const std::vector< uint8_t > &	buf,
		OpaqueDataTuple::LengthFieldType	lengthfieldtype
	)

static

Read length and string tuple from a buffer.

Parameters

buf	input buffer.
lengthfieldtype	LENGTH_1_BYTE (DHCPv4) or LENGTH_2_BYTES (DHCPv6)

Exceptions

isc::dhcp::BadDataTypeCast when the data being read is truncated.

Returns: string being read.

Definition at line 205 of file option_data_types.cc.

References isc_throw, isc::dhcp::OpaqueDataTuple::LENGTH_1_BYTE, isc::dhcp::OpaqueDataTuple::LENGTH_2_BYTES, and isc::util::readUint16().

Referenced by isc::dhcp::OptionCustom::readTuple().

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◆ writeAddress()

void isc::dhcp::OptionDataTypeUtil::writeAddress	(	const asiolink::IOAddress &	address,
		std::vector< uint8_t > &	buf
	)

static

Append IPv4 or IPv6 address to a buffer.

Parameters

	address	IPv4 or IPv6 address.
[out]	buf	output buffer.

Definition at line 172 of file option_data_types.cc.

References isc::asiolink::IOAddress::toBytes().

Referenced by isc::dhcp::OptionCustom::addArrayDataField(), and isc::dhcp::OptionCustom::writeAddress().

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◆ writeBinary()

void isc::dhcp::OptionDataTypeUtil::writeBinary	(	const std::string &	hex_str,
		std::vector< uint8_t > &	buf
	)

static

Append hex-encoded binary values to a buffer.

Parameters

	hex_str	string representing a binary value encoded with hexadecimal digits (without 0x prefix).
[out]	buf	output buffer.

Definition at line 179 of file option_data_types.cc.

References isc::util::encode::decodeHex(), isc_throw, and isc::Exception::what().

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◆ writeBool()

void isc::dhcp::OptionDataTypeUtil::writeBool	(	const bool	value,
		std::vector< uint8_t > &	buf
	)

static

Append boolean value into a buffer.

The bool value is encoded in a buffer in such a way that "1" means "true" and "0" means "false".

Parameters

	value	boolean value to be written.
[out]	buf	output buffer.

Definition at line 332 of file option_data_types.cc.

Referenced by isc::dhcp::OptionCustom::addArrayDataField(), and isc::dhcp::OptionCustom::writeBoolean().

◆ writeFqdn()

void isc::dhcp::OptionDataTypeUtil::writeFqdn	(	const std::string &	fqdn,
		std::vector< uint8_t > &	buf,
		const bool	downcase = `false`
	)

static

Append FQDN into a buffer.

This method appends the Fully Qualified Domain Name (FQDN) represented as string value into a buffer. The format of the FQDN being stored into a buffer complies with RFC1035, section 3.1.

Parameters

	fqdn	fully qualified domain name to be written.
[out]	buf	output buffer.
	downcase	indicates if the FQDN should be converted to lower case (if true). By default it is not converted.

Exceptions

isc::dhcp::BadDataTypeCast if provided FQDN is invalid.

Definition at line 359 of file option_data_types.cc.

References isc::dns::LabelSequence::getData(), isc::dns::LabelSequence::getDataLength(), isc_throw, and isc::Exception::what().

Referenced by isc::dhcp::OptionCustom::writeFqdn().

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◆ writeInt()

template<typename T >

static void isc::dhcp::OptionDataTypeUtil::writeInt	(	const T	value,
		std::vector< uint8_t > &	buf
	)

inlinestatic

Append integer or unsigned integer value to a buffer.

Parameters

	value	an integer value to be written into a buffer.
[out]	buf	output buffer.

Template Parameters

data	type of the value.

Definition at line 503 of file option_data_types.h.

References isc_throw, isc::util::writeUint16(), and isc::util::writeUint32().

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◆ writePrefix()

void isc::dhcp::OptionDataTypeUtil::writePrefix	(	const PrefixLen &	prefix_len,
		const asiolink::IOAddress &	prefix,
		std::vector< uint8_t > &	buf
	)

static

Append prefix into a buffer.

This method writes prefix length (1 byte) followed by a variable length prefix.

Parameters

	prefix_len	Prefix length in bits (0 to 128).
	prefix	Prefix value.
[out]	buf	Output buffer.

Definition at line 490 of file option_data_types.cc.

References isc::dhcp::PrefixLen::asUint8(), isc_throw, isc::asiolink::IOAddress::isV6(), and isc::asiolink::IOAddress::toBytes().

Referenced by isc::dhcp::OptionCustom::addArrayDataField(), and isc::dhcp::OptionCustom::writePrefix().

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◆ writePsid()

void isc::dhcp::OptionDataTypeUtil::writePsid	(	const PSIDLen &	psid_len,
		const PSID &	psid,
		std::vector< uint8_t > &	buf
	)

static

Append PSID length/value into a buffer.

This method appends 1 byte of PSID length and 2 bytes of PSID value into a buffer. The PSID value contains a PSID length number of significant bits, followed by 16 - PSID length zero bits.

Parameters

	psid_len	PSID length in the range of 0 to 16 holding the number of significant bits within the PSID value.
	psid	PSID value, where the lowest value is 0, and the highest value is 2^(PSID length)-1.
[out]	buf	output buffer.

Exceptions

isc::dhcp::BadDataTypeCast if specified psid_len or psid value is incorrect.

Definition at line 571 of file option_data_types.cc.

References isc::dhcp::PSID::asUint16(), isc::dhcp::PSIDLen::asUint8(), isc::dhcp::PSIDLen::asUnsigned(), isc_throw, and isc::util::writeUint16().

Referenced by isc::dhcp::OptionCustom::addArrayDataField(), and isc::dhcp::OptionCustom::writePsid().

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◆ writeString()

void isc::dhcp::OptionDataTypeUtil::writeString	(	const std::string &	value,
		std::vector< uint8_t > &	buf
	)

static

Write UTF8-encoded string into a buffer.

Parameters

	value	string value to be written into a buffer.
[out]	buf	output buffer.

Definition at line 612 of file option_data_types.cc.

Referenced by isc::dhcp::OptionCustom::writeString().

◆ writeTuple() [1/2]

void isc::dhcp::OptionDataTypeUtil::writeTuple	(	const OpaqueDataTuple &	tuple,
		std::vector< uint8_t > &	buf
	)

static

Append length and string tuple to a buffer.

Parameters

	tuple	length and string tuple
[out]	buf	output buffer.

Definition at line 286 of file option_data_types.cc.

References isc::dhcp::OpaqueDataTuple::getData(), isc::dhcp::OpaqueDataTuple::getLength(), isc::dhcp::OpaqueDataTuple::getLengthFieldType(), isc_throw, isc::dhcp::OpaqueDataTuple::LENGTH_1_BYTE, isc::dhcp::OpaqueDataTuple::LENGTH_2_BYTES, and isc::util::writeUint16().

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◆ writeTuple() [2/2]

void isc::dhcp::OptionDataTypeUtil::writeTuple	(	const std::string &	value,
		OpaqueDataTuple::LengthFieldType	lengthfieldtype,
		std::vector< uint8_t > &	buf
	)

static

Append length and string tuple to a buffer.

Parameters

	value	length and string tuple
	lengthfieldtype	LENGTH_1_BYTE (DHCPv4) or LENGTH_2_BYTES (DHCPv6)
[out]	buf	output buffer.

Definition at line 257 of file option_data_types.cc.

References isc_throw, isc::dhcp::OpaqueDataTuple::LENGTH_1_BYTE, isc::dhcp::OpaqueDataTuple::LENGTH_2_BYTES, and isc::util::writeUint16().

Referenced by isc::dhcp::OptionCustom::addArrayDataField(), and isc::dhcp::OptionCustom::writeTuple().

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

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ getDataType()

◆ getDataTypeLen()

◆ getDataTypeName()

◆ getLabelCount()

◆ getTupleLenFieldType()

◆ readAddress()

◆ readBool()

◆ readFqdn()

◆ readInt()

◆ readPrefix()

◆ readPsid()

◆ readString()

◆ readTuple() [1/2]

◆ readTuple() [2/2]

◆ writeAddress()

◆ writeBinary()

◆ writeBool()

◆ writeFqdn()

◆ writeInt()

◆ writePrefix()

◆ writePsid()

◆ writeString()

◆ writeTuple() [1/2]

◆ writeTuple() [2/2]