#include <dns.h>

Inheritance diagram for Tins::DNS:

Classes
class	query
	Struct that represent DNS queries. More...
class	soa_record
	Class that represents a Start Of Authority record. More...
class	resource
	Class that represent DNS resource records. More...

Public Types
enum	QRType { QUERY = 0 , RESPONSE = 1 }
enum	QueryType { A = 1 , NS , MD , MF , CNAME , SOA , MB , MG , MR , NULL_R , WKS , PTR , HINFO , MINFO , MX , TXT , RP , AFSDB , X25 , ISDN , RT , NSAP , NSAP_PTR , SIG , KEY , PX , GPOS , AAAA , LOC , NXT , EID , NIMLOC , SRV , ATMA , NAPTR , KX , CERTIFICATE , A6 , DNAM , SINK , OPT , APL , DS , SSHFP , IPSECKEY , RRSIG , NSEC , DNSKEY , DHCID , NSEC3 , NSEC3PARAM , CERT = CERTIFICATE }
	Query types enum.
enum	QueryClass { INTERNET = 1 , CHAOS = 3 , HESIOD = 4 , ANY = 255 }
typedef std::vector< query >	queries_type
typedef std::vector< resource >	resources_type
typedef IPv4Address	address_type
typedef IPv6Address	address_v6_type
Public Types inherited from Tins::PDU
enum	endian_type { BE , LE }
enum	PDUType { RAW , ETHERNET_II , IEEE802_3 , DOT3 = IEEE802_3 , RADIOTAP , DOT11 , DOT11_ACK , DOT11_ASSOC_REQ , DOT11_ASSOC_RESP , DOT11_AUTH , DOT11_BEACON , DOT11_BLOCK_ACK , DOT11_BLOCK_ACK_REQ , DOT11_CF_END , DOT11_DATA , DOT11_CONTROL , DOT11_DEAUTH , DOT11_DIASSOC , DOT11_END_CF_ACK , DOT11_MANAGEMENT , DOT11_PROBE_REQ , DOT11_PROBE_RESP , DOT11_PS_POLL , DOT11_REASSOC_REQ , DOT11_REASSOC_RESP , DOT11_RTS , DOT11_QOS_DATA , LLC , SNAP , IP , ARP , TCP , UDP , ICMP , BOOTP , DHCP , EAPOL , RC4EAPOL , RSNEAPOL , DNS , LOOPBACK , IPv6 , ICMPv6 , SLL , DHCPv6 , DOT1AD , DOT1Q , PPPOE , STP , PPI , IPSEC_AH , IPSEC_ESP , PKTAP , MPLS , DOT11_CONTROL_TA , VXLAN , UNKNOWN = 999 , USER_DEFINED_PDU = 1000 }
	Enum which identifies each type of PDU. More...
typedef byte_array	serialization_type

Public Member Functions
	TINS_DEPRECATED (typedef query Query)
	TINS_DEPRECATED (typedef resource Resource)
	DNS ()
	Default constructor.
	DNS (const uint8_t *buffer, uint32_t total_sz)
	Constructs a DNS object from a buffer.
uint16_t	id () const
	Getter for the id field.
QRType	type () const
	Getter for the query response field.
uint8_t	opcode () const
	Getter for the opcode field.
uint8_t	authoritative_answer () const
	Getter for the authoritative answer field.
uint8_t	truncated () const
	Getter for the truncated field.
uint8_t	recursion_desired () const
	Getter for the recursion desired field.
uint8_t	recursion_available () const
	Getter for the recursion available field.
uint8_t	z () const
	Getter for the z desired field.
uint8_t	authenticated_data () const
	Getter for the authenticated data field.
uint8_t	checking_disabled () const
	Getter for the checking disabled field.
uint8_t	rcode () const
	Getter for the rcode field.
uint16_t	questions_count () const
	Getter for the questions field.
uint16_t	answers_count () const
	Getter for the answers field.
uint16_t	authority_count () const
	Getter for the authority field.
uint16_t	additional_count () const
	Getter for the additional field.
PDUType	pdu_type () const
	Getter for the PDU's type.
uint32_t	header_size () const
	The header's size.
void	id (uint16_t new_id)
	Setter for the id field.
void	type (QRType new_qr)
	Setter for the query response field.
void	opcode (uint8_t new_opcode)
	Setter for the opcode field.
void	authoritative_answer (uint8_t new_aa)
	Setter for the authoritative answer field.
void	truncated (uint8_t new_tc)
	Setter for the truncated field.
void	recursion_desired (uint8_t new_rd)
	Setter for the recursion desired field.
void	recursion_available (uint8_t new_ra)
	Setter for the recursion available field.
void	z (uint8_t new_z)
	Setter for the z(reserved) field.
void	authenticated_data (uint8_t new_ad)
	Setter for the authenticated data field.
void	checking_disabled (uint8_t new_cd)
	Setter for the checking disabled field.
void	rcode (uint8_t new_rcode)
	Setter for the rcode field.
void	add_query (const query &query)
	Add a query to perform.
void	add_answer (const resource &resource)
	Add an answer resource record.
void	add_authority (const resource &resource)
	Add an authority resource record.
void	add_additional (const resource &resource)
	Add an additional resource record.
queries_type	queries () const
	Getter for this PDU's DNS queries.
resources_type	answers () const
	Getter for this PDU's DNS answers.
resources_type	authority () const
	Getter for this PDU's DNS authority records.
resources_type	additional () const
	Getter for this PDU's DNS additional records.
bool	matches_response (const uint8_t *ptr, uint32_t total_sz) const
	Check whether ptr points to a valid response for this PDU.
DNS *	clone () const
Public Member Functions inherited from Tins::PDU
	PDU ()
	Default constructor.
	PDU (PDU &&rhs) TINS_NOEXCEPT
	Move constructor.
PDU &	operator= (PDU &&rhs) TINS_NOEXCEPT
	Move assignment operator.
virtual	~PDU ()
	PDU destructor.
virtual uint32_t	trailer_size () const
	Trailer's size.
uint32_t	size () const
	The whole chain of PDU's size, including this one.
virtual uint32_t	advertised_size () const
	The whole chain of PDU's advertised size, including this one.
PDU *	inner_pdu () const
	Getter for the inner PDU.
PDU *	parent_pdu () const
PDU *	release_inner_pdu ()
	Releases the inner PDU.
void	inner_pdu (PDU *next_pdu)
	Sets the child PDU.
void	inner_pdu (const PDU &next_pdu)
	Sets the child PDU.
serialization_type	serialize ()
	Serializes the whole chain of PDU's, including this one.
template<typename T>
T *	find_pdu (PDUType type=T::pdu_flag)
	Finds and returns the first PDU that matches the given flag.
template<typename T>
const T *	find_pdu (PDUType type=T::pdu_flag) const
	Finds and returns the first PDU that matches the given flag.
template<typename T>
T &	rfind_pdu (PDUType type=T::pdu_flag)
	Finds and returns the first PDU that matches the given flag.
template<typename T>
const T &	rfind_pdu (PDUType type=T::pdu_flag) const
	Finds and returns the first PDU that matches the given flag.
virtual void	send (PacketSender &sender, const NetworkInterface &iface)
	Send the stack of PDUs through a PacketSender.
virtual PDU *	recv_response (PacketSender &sender, const NetworkInterface &iface)
	Receives a matching response for this packet.
virtual bool	matches_flag (PDUType flag) const
	Check whether this PDU matches the specified flag.

Static Public Member Functions
static metadata	extract_metadata (const uint8_t *buffer, uint32_t total_sz)
	Extracts metadata for this protocol based on the buffer provided.
static std::string	encode_domain_name (const std::string &domain_name)
	Encodes a domain name.
static std::string	decode_domain_name (const std::string &domain_name)
	Decodes a domain name.

Static Public Attributes
static const PDU::PDUType	pdu_flag = PDU::DNS
	This PDU's flag.
Static Public Attributes inherited from Tins::PDU
static const endian_type	endianness = BE

Friends
class	soa_record

Additional Inherited Members
Protected Member Functions inherited from Tins::PDU
	PDU (const PDU &other)
	Copy constructor.
PDU &	operator= (const PDU &other)
	Copy assignment operator.
void	copy_inner_pdu (const PDU &pdu)
	Copy other PDU's inner PDU(if any).
virtual void	prepare_for_serialize ()
	Prepares this PDU for serialization.
void	serialize (uint8_t *buffer, uint32_t total_sz)
	Serializes this PDU and propagates this action to child PDUs.

Detailed Description

Represents a DNS PDU.

This class represents the DNS PDU, and allows easy access to queries and answer records.

The DNS PDU is not parsed automatically while sniffing, so you will have to parse it manually from an UDP packet's payload, for example:

// Assume we get an udp packet from somewhere.
UDP udp = get_udp_packet();
 
// Now:
// 1 - Get the RawPDU layer (contains the payload).
// 2 - Construct a DNS object over its contents.
DNS dns = udp.rfind_pdu<RawPDU>().to<DNS>();
 
// Now use the DNS object!
for(const auto& query : dns.queries()) {
    // Process a query
}

Member Enumeration Documentation

◆ QRType

enum Tins::DNS::QRType

The DNS type.

Constructor & Destructor Documentation

◆ DNS() [1/2]

Tins::DNS::DNS ( )

Default constructor.

This constructor initializes every field to 0.

◆ DNS() [2/2]

Tins::DNS::DNS	(	const uint8_t *	buffer,
		uint32_t	total_sz )

Constructs a DNS object from a buffer.

If there's not enough size for the DNS header, or any of the records are malformed, a malformed_packet is be thrown.

Parameters

buffer	The buffer from which this PDU will be constructed.
total_sz	The total size of the buffer.

Member Function Documentation

◆ add_additional()

void Tins::DNS::add_additional ( const resource & resource )

Add an additional resource record.

Parameters

resource The resource to be added.

◆ add_answer()

void Tins::DNS::add_answer ( const resource & resource )

Add an answer resource record.

Parameters

resource The resource to be added.

◆ add_authority()

void Tins::DNS::add_authority ( const resource & resource )

Add an authority resource record.

Parameters

resource The resource to be added.

◆ add_query()

void Tins::DNS::add_query ( const query & query )

Add a query to perform.

Parameters

query The query to be added.

◆ additional()

DNS::resources_type Tins::DNS::additional ( ) const

Getter for this PDU's DNS additional records.

Returns: The additional records in this PDU.

◆ additional_count()

uint16_t Tins::DNS::additional_count ( ) const

inline

Getter for the additional field.

Returns: uint16_t containing the value of the additional field.

◆ answers()

DNS::resources_type Tins::DNS::answers ( ) const

Getter for this PDU's DNS answers.

Returns: The answer records in this PDU.

◆ answers_count()

uint16_t Tins::DNS::answers_count ( ) const

inline

Getter for the answers field.

Returns: uint16_t containing the value of the answers field.

◆ authenticated_data() [1/2]

uint8_t Tins::DNS::authenticated_data ( ) const

inline

Getter for the authenticated data field.

Returns: uint8_t containing the value of the authenticated data field.

◆ authenticated_data() [2/2]

void Tins::DNS::authenticated_data ( uint8_t new_ad )

Setter for the authenticated data field.

Parameters

new_ad The new authenticated data value to be set.

◆ authoritative_answer() [1/2]

uint8_t Tins::DNS::authoritative_answer ( ) const

inline

Getter for the authoritative answer field.

Returns: uint8_t containing the value of the authoritative answer field.

◆ authoritative_answer() [2/2]

void Tins::DNS::authoritative_answer ( uint8_t new_aa )

Setter for the authoritative answer field.

Parameters

new_aa The new authoritative answer field value to be set.

◆ authority()

DNS::resources_type Tins::DNS::authority ( ) const

Getter for this PDU's DNS authority records.

Returns: The authority records in this PDU.

◆ authority_count()

uint16_t Tins::DNS::authority_count ( ) const

inline

Getter for the authority field.

Returns: uint16_t containing the value of the authority field.

◆ checking_disabled() [1/2]

uint8_t Tins::DNS::checking_disabled ( ) const

inline

Getter for the checking disabled field.

Returns: uint8_t containing the value of the checking disabled field.

◆ checking_disabled() [2/2]

void Tins::DNS::checking_disabled ( uint8_t new_cd )

Setter for the checking disabled field.

Parameters

new_z The new checking disabled value to be set.

◆ clone()

DNS * Tins::DNS::clone ( ) const

inlinevirtual

See also: PDU::clone

Implements Tins::PDU.

◆ decode_domain_name()

string Tins::DNS::decode_domain_name ( const std::string & domain_name )

static

Decodes a domain name.

This method processes an encoded domain name and returns the decoded version. This can't handle offset labels.

For example, given the input "\x03www\x07example\x03com\x00", the output would be www.example.com".

Parameters

domain_name The domain name to decode.

Returns: The decoded domain name.

◆ encode_domain_name()

string Tins::DNS::encode_domain_name ( const std::string & domain_name )

static

Encodes a domain name.

This processes the input domain name and returns the encoded version. Each label in the original domain name will be prefixed with a byte that indicates the label's length. The null-terminator byte will be included in the encoded string. No compression is performed.

For example, given the input "www.example.com", the output would be "\x03www\x07example\x03com\x00".

Parameters

domain_name The domain name to encode.

Returns: The encoded domain name.

◆ extract_metadata()

PDU::metadata Tins::DNS::extract_metadata	(	const uint8_t *	buffer,
		uint32_t	total_sz )

static

Extracts metadata for this protocol based on the buffer provided.

Parameters

buffer	Pointer to a buffer
total_sz	Size of the buffer pointed by buffer

◆ header_size()

uint32_t Tins::DNS::header_size ( ) const

virtual

The header's size.

Implements Tins::PDU.

◆ id() [1/2]

uint16_t Tins::DNS::id ( ) const

inline

Getter for the id field.

Returns: uint16_t containing the value of the id field.

◆ id() [2/2]

void Tins::DNS::id ( uint16_t new_id )

Setter for the id field.

Parameters

new_id The new id to be set.

◆ matches_response()

bool Tins::DNS::matches_response	(	const uint8_t *	ptr,
		uint32_t	total_sz ) const

virtual

Check whether ptr points to a valid response for this PDU.

See also: PDU::matches_response

Parameters

ptr	The pointer to the buffer.
total_sz	The size of the buffer.

Reimplemented from Tins::PDU.

◆ opcode() [1/2]

uint8_t Tins::DNS::opcode ( ) const

inline

Getter for the opcode field.

Returns: uint8_t containing the value of the opcode field.

◆ opcode() [2/2]

void Tins::DNS::opcode ( uint8_t new_opcode )

Setter for the opcode field.

Parameters

new_opcode The new opcode to be set.

◆ pdu_type()

PDUType Tins::DNS::pdu_type ( ) const

inlinevirtual

Getter for the PDU's type.

Returns: Returns the PDUType corresponding to the PDU.

Implements Tins::PDU.

◆ queries()

DNS::queries_type Tins::DNS::queries ( ) const

Getter for this PDU's DNS queries.

Returns: The query records in this PDU.

◆ questions_count()

uint16_t Tins::DNS::questions_count ( ) const

inline

Getter for the questions field.

Returns: uint16_t containing the value of the questions field.

◆ rcode() [1/2]

uint8_t Tins::DNS::rcode ( ) const

inline

Getter for the rcode field.

Returns: uint8_t containing the value of the rcode field.

◆ rcode() [2/2]

void Tins::DNS::rcode ( uint8_t new_rcode )

Setter for the rcode field.

Parameters

new_rcode The new rcode value to be set.

◆ recursion_available() [1/2]

uint8_t Tins::DNS::recursion_available ( ) const

inline

Getter for the recursion available field.

Returns: uint8_t containing the value of the recursion available field.

◆ recursion_available() [2/2]

void Tins::DNS::recursion_available ( uint8_t new_ra )

Setter for the recursion available field.

Parameters

new_ra The new recursion available value to be set.

◆ recursion_desired() [1/2]

uint8_t Tins::DNS::recursion_desired ( ) const

inline

Getter for the recursion desired field.

Returns: uint8_t containing the value of the recursion desired field.

◆ recursion_desired() [2/2]

void Tins::DNS::recursion_desired ( uint8_t new_rd )

Setter for the recursion desired field.

Parameters

new_rd The new recursion desired value to be set.

◆ truncated() [1/2]

uint8_t Tins::DNS::truncated ( ) const

inline

Getter for the truncated field.

Returns: uint8_t containing the value of the truncated field.

◆ truncated() [2/2]

void Tins::DNS::truncated ( uint8_t new_tc )

Setter for the truncated field.

Parameters

new_tc The new truncated field value to be set.

◆ type() [1/2]

QRType Tins::DNS::type ( ) const

inline

Getter for the query response field.

Returns: QRType containing the value of the query response field.

◆ type() [2/2]

void Tins::DNS::type ( QRType new_qr )

Setter for the query response field.

Parameters

new_qr The new qr to be set.

◆ z() [1/2]

uint8_t Tins::DNS::z ( ) const

inline

Getter for the z desired field.

Returns: uint8_t containing the value of the z field.

◆ z() [2/2]

void Tins::DNS::z ( uint8_t new_z )

Setter for the z(reserved) field.

Parameters

new_z The new z value to be set.

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

/builddir/build/BUILD/libtins-4.5-build/libtins-4.5/include/tins/dns.h
/builddir/build/BUILD/libtins-4.5-build/libtins-4.5/src/dns.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ QRType

Constructor & Destructor Documentation

◆ DNS() [1/2]

◆ DNS() [2/2]

Member Function Documentation

◆ add_additional()

◆ add_answer()

◆ add_authority()

◆ add_query()

◆ additional()

◆ additional_count()

◆ answers()

◆ answers_count()

◆ authenticated_data() [1/2]

◆ authenticated_data() [2/2]

◆ authoritative_answer() [1/2]

◆ authoritative_answer() [2/2]

◆ authority()

◆ authority_count()

◆ checking_disabled() [1/2]

◆ checking_disabled() [2/2]

◆ clone()

◆ decode_domain_name()

◆ encode_domain_name()

◆ extract_metadata()

◆ header_size()

◆ id() [1/2]

◆ id() [2/2]

◆ matches_response()

◆ opcode() [1/2]

◆ opcode() [2/2]

◆ pdu_type()

◆ queries()

◆ questions_count()

◆ rcode() [1/2]

◆ rcode() [2/2]

◆ recursion_available() [1/2]

◆ recursion_available() [2/2]

◆ recursion_desired() [1/2]

◆ recursion_desired() [2/2]

◆ truncated() [1/2]

◆ truncated() [2/2]

◆ type() [1/2]

◆ type() [2/2]

◆ z() [1/2]

◆ z() [2/2]