Implementation of the DNS protocol. More...

#include <freeradius-devel/util/packet.h>
#include <freeradius-devel/util/dns.h>

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Data Structures
struct	fr_dns_attr_flags_t

struct	fr_dns_ctx_t

struct	fr_dns_packet_t

Macros
#define	DNS_HDR_LEN (12)

#define	DNS_MAX_ATTRIBUTES 255

#define	fr_dns_flag_dns_label(_da) (fr_dns_attr_flags(_da)->dns_label)

#define	fr_dns_flag_dns_label_uncompressed(_da) (fr_dns_attr_flags(_da)->dns_label_uncompressed)

#define	FR_DNS_PACKET_CODE_VALID(_code) (((_code) < FR_DNS_CODE_MAX) \|\| (((_code & 0x10) != 0) && ((_code & ~0x10) < FR_DNS_CODE_MAX)))

Enumerations
enum	fr_dns_decode_fail_t { FR_DNS_DECODE_FAIL_NONE = 0 , FR_DNS_DECODE_FAIL_UNKNOWN_OPCODE , FR_DNS_DECODE_FAIL_MIN_LENGTH_PACKET , FR_DNS_DECODE_FAIL_MAX_LENGTH_PACKET , FR_DNS_DECODE_FAIL_UNEXPECTED , FR_DNS_DECODE_FAIL_NO_QUESTIONS , FR_DNS_DECODE_FAIL_ANSWERS_IN_QUESTION , FR_DNS_DECODE_FAIL_NS_IN_QUESTION , FR_DNS_DECODE_FAIL_INVALID_RR_LABEL , FR_DNS_DECODE_FAIL_MISSING_RR_HEADER , FR_DNS_DECODE_FAIL_MISSING_RR_LEN , FR_DNS_DECODE_FAIL_ZERO_RR_LEN , FR_DNS_DECODE_FAIL_RR_OVERFLOWS_PACKET , FR_DNS_DECODE_FAIL_TOO_MANY_RRS , FR_DNS_DECODE_FAIL_TOO_FEW_RRS , FR_DNS_DECODE_FAIL_POINTER_TO_NON_LABEL , FR_DNS_DECODE_FAIL_POINTER_OVERFLOWS_PACKET , FR_DNS_DECODE_FAIL_POINTER_TO_HEADER , FR_DNS_DECODE_FAIL_POINTER_LOOPS , FR_DNS_DECODE_FAIL_INVALID_POINTER , FR_DNS_DECODE_FAIL_LABEL_OVERFLOWS_PACKET , FR_DNS_DECODE_FAIL_LABEL_TOO_LONG , FR_DNS_DECODE_FAIL_MISSING_QD_HEADER , FR_DNS_DECODE_FAIL_MISSING_TLV_HEADER , FR_DNS_DECODE_FAIL_TLV_OVERFLOWS_RR , FR_DNS_DECODE_FAIL_TRUNCATED , FR_DNS_DECODE_FAIL_MAX }

enum	fr_dns_packet_code_t { FR_DNS_QUERY = 0 , FR_DNS_INVERSE_QUERY = 1 , FR_DNS_STATUS = 2 , FR_DNS_NOTIFY = 4 , FR_DNS_UPDATE = 5 , FR_DNS_STATEFUL_OPERATION = 6 , FR_DNS_CODE_MAX = 7 , FR_DNS_QUERY_RESPONSE = 16 , FR_DNS_INVERSE_QUERY_RESPONSE = 17 , FR_DNS_STATUS_RESPONSE = 18 , FR_DNS_NOTIFY_RESPONSE = 20 , FR_DNS_UPDATE_RESPONSE = 21 , FR_DNS_STATEFUL_OPERATION_RESPONSE = 22 , FR_DNS_DO_NOT_RESPOND = 256 }

Functions
static fr_dns_attr_flags_t const *	fr_dns_attr_flags (fr_dict_attr_t const *da)

ssize_t	fr_dns_decode (TALLOC_CTX ctx, fr_pair_list_t out, uint8_t const packet, size_t packet_len, fr_dns_ctx_t packet_ctx)
	Decode a DNS packet.

ssize_t	fr_dns_encode (fr_dbuff_t dbuff, fr_pair_list_t vps, fr_dns_ctx_t *encode_ctx)
	Encode a DNS packet.

static bool	fr_dns_flag_dns_label_any (fr_dict_attr_t const *da)

void	fr_dns_global_free (void)

int	fr_dns_global_init (void)
	Resolve/cache attributes in the DNS dictionary.

fr_dns_labels_t *	fr_dns_labels_get (uint8_t const *packet, size_t packet_len, bool init_mark)

bool	fr_dns_packet_ok (uint8_t const packet, size_t packet_len, bool query, fr_dns_decode_fail_t reason)

Variables
char const *	fr_dns_packet_names [FR_DNS_CODE_MAX]

fr_table_num_ordered_t	fr_dns_reason_fail_table []

size_t	fr_dns_reason_fail_table_len

Detailed Description

Implementation of the DNS protocol.

Id: ca83b3b34a2820892bacf25f49188a296447dbd2

Copyright: 2021 Network RADIUS SAS (legal.nosp@m.@net.nosp@m.workr.nosp@m.adiu.nosp@m.s.com)

Definition in file dns.h.

Data Structure Documentation

◆ fr_dns_attr_flags_t

struct fr_dns_attr_flags_t

Definition at line 136 of file dns.h.

Data Fields
bool	dns_label
bool	dns_label_uncompressed

◆ fr_dns_ctx_t

struct fr_dns_ctx_t

Definition at line 73 of file dns.h.

Collaboration diagram for fr_dns_ctx_t:

Data Fields
fr_dns_labels_t *	lb
uint8_t const *	packet	DNS labels can point anywhere in the packet :(.
size_t	packet_len
TALLOC_CTX *	tmp_ctx	for temporary things cleaned up during decoding

◆ fr_dns_packet_t

struct fr_dns_packet_t

Definition at line 37 of file dns.h.

Data Fields
uint16_t	ancount
uint16_t	arcount
unsigned int	authentic_data: 1
unsigned int	authoritative: 1
unsigned int	checking_disabled: 1
uint16_t	id
uint16_t	nscount
unsigned int	opcode: 4
uint16_t	qdcount
unsigned int	query: 1
unsigned int	rcode: 4
unsigned int	recursion_available: 1
unsigned int	recursion_desired: 1
unsigned int	reserved: 1
unsigned int	truncated: 1

Macro Definition Documentation

◆ DNS_HDR_LEN

#define DNS_HDR_LEN (12)

Definition at line 134 of file dns.h.

◆ DNS_MAX_ATTRIBUTES

#define DNS_MAX_ATTRIBUTES 255

Definition at line 35 of file dns.h.

◆ fr_dns_flag_dns_label

#define fr_dns_flag_dns_label ( _da ) (fr_dns_attr_flags(_da)->dns_label)

Definition at line 153 of file dns.h.

◆ fr_dns_flag_dns_label_uncompressed

#define fr_dns_flag_dns_label_uncompressed ( _da ) (fr_dns_attr_flags(_da)->dns_label_uncompressed)

Definition at line 154 of file dns.h.

◆ FR_DNS_PACKET_CODE_VALID

#define FR_DNS_PACKET_CODE_VALID ( _code ) (((_code) < FR_DNS_CODE_MAX) || (((_code & 0x10) != 0) && ((_code & ~0x10) < FR_DNS_CODE_MAX)))

Definition at line 132 of file dns.h.

Enumeration Type Documentation

◆ fr_dns_decode_fail_t

enum fr_dns_decode_fail_t

Enumerator
FR_DNS_DECODE_FAIL_NONE
FR_DNS_DECODE_FAIL_UNKNOWN_OPCODE
FR_DNS_DECODE_FAIL_MIN_LENGTH_PACKET
FR_DNS_DECODE_FAIL_MAX_LENGTH_PACKET
FR_DNS_DECODE_FAIL_UNEXPECTED
FR_DNS_DECODE_FAIL_NO_QUESTIONS
FR_DNS_DECODE_FAIL_ANSWERS_IN_QUESTION
FR_DNS_DECODE_FAIL_NS_IN_QUESTION
FR_DNS_DECODE_FAIL_INVALID_RR_LABEL
FR_DNS_DECODE_FAIL_MISSING_RR_HEADER
FR_DNS_DECODE_FAIL_MISSING_RR_LEN
FR_DNS_DECODE_FAIL_ZERO_RR_LEN
FR_DNS_DECODE_FAIL_RR_OVERFLOWS_PACKET
FR_DNS_DECODE_FAIL_TOO_MANY_RRS
FR_DNS_DECODE_FAIL_TOO_FEW_RRS
FR_DNS_DECODE_FAIL_POINTER_TO_NON_LABEL
FR_DNS_DECODE_FAIL_POINTER_OVERFLOWS_PACKET
FR_DNS_DECODE_FAIL_POINTER_TO_HEADER
FR_DNS_DECODE_FAIL_POINTER_LOOPS
FR_DNS_DECODE_FAIL_INVALID_POINTER
FR_DNS_DECODE_FAIL_LABEL_OVERFLOWS_PACKET
FR_DNS_DECODE_FAIL_LABEL_TOO_LONG
FR_DNS_DECODE_FAIL_MISSING_QD_HEADER
FR_DNS_DECODE_FAIL_MISSING_TLV_HEADER
FR_DNS_DECODE_FAIL_TLV_OVERFLOWS_RR
FR_DNS_DECODE_FAIL_TRUNCATED
FR_DNS_DECODE_FAIL_MAX

Definition at line 102 of file dns.h.

◆ fr_dns_packet_code_t

enum fr_dns_packet_code_t

Enumerator
FR_DNS_QUERY
FR_DNS_INVERSE_QUERY
FR_DNS_STATUS
FR_DNS_NOTIFY
FR_DNS_UPDATE
FR_DNS_STATEFUL_OPERATION
FR_DNS_CODE_MAX
FR_DNS_QUERY_RESPONSE
FR_DNS_INVERSE_QUERY_RESPONSE
FR_DNS_STATUS_RESPONSE
FR_DNS_NOTIFY_RESPONSE
FR_DNS_UPDATE_RESPONSE
FR_DNS_STATEFUL_OPERATION_RESPONSE
FR_DNS_DO_NOT_RESPOND

Definition at line 83 of file dns.h.

Function Documentation

◆ fr_dns_attr_flags()

static fr_dns_attr_flags_t const * fr_dns_attr_flags ( fr_dict_attr_t const * da )

inlinestatic

Definition at line 141 of file dns.h.

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◆ fr_dns_decode()

ssize_t fr_dns_decode	(	TALLOC_CTX *	ctx,
		fr_pair_list_t *	out,
		uint8_t const *	packet,
		size_t	packet_len,
		fr_dns_ctx_t *	packet_ctx
	)

Decode a DNS packet.

Definition at line 234 of file decode.c.

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◆ fr_dns_encode()

ssize_t fr_dns_encode	(	fr_dbuff_t *	dbuff,
		fr_pair_list_t *	vps,
		fr_dns_ctx_t *	encode_ctx
	)

Encode a DNS packet.

Definition at line 451 of file encode.c.

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◆ fr_dns_flag_dns_label_any()

static bool fr_dns_flag_dns_label_any ( fr_dict_attr_t const * da )

inlinestatic

Definition at line 146 of file dns.h.

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◆ fr_dns_global_free()

void fr_dns_global_free ( void )

Definition at line 472 of file base.c.

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◆ fr_dns_global_init()

int fr_dns_global_init ( void )

Resolve/cache attributes in the DNS dictionary.

Returns

0 on success.
-1 on failure.

Definition at line 449 of file base.c.

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◆ fr_dns_labels_get()

fr_dns_labels_t * fr_dns_labels_get	(	uint8_t const *	packet,
		size_t	packet_len,
		bool	init_mark
	)

Definition at line 420 of file base.c.

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◆ fr_dns_packet_ok()

bool fr_dns_packet_ok	(	uint8_t const *	packet,
		size_t	packet_len,
		bool	query,
		fr_dns_decode_fail_t *	reason
	)

Definition at line 109 of file base.c.

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Variable Documentation

◆ fr_dns_packet_names

char const* fr_dns_packet_names[FR_DNS_CODE_MAX]

extern

Definition at line 68 of file base.c.

◆ fr_dns_reason_fail_table

fr_table_num_ordered_t fr_dns_reason_fail_table[]

extern

Definition at line 361 of file decode.c.

◆ fr_dns_reason_fail_table_len

size_t fr_dns_reason_fail_table_len

extern

Definition at line 389 of file decode.c.

Data Structures

Macros

Enumerations

Functions

Variables

Detailed Description

Data Structure Documentation

◆ fr_dns_attr_flags_t

◆ fr_dns_ctx_t

◆ fr_dns_packet_t

Macro Definition Documentation

◆ DNS_HDR_LEN

◆ DNS_MAX_ATTRIBUTES

◆ fr_dns_flag_dns_label

◆ fr_dns_flag_dns_label_uncompressed

◆ FR_DNS_PACKET_CODE_VALID

Enumeration Type Documentation

◆ fr_dns_decode_fail_t

◆ fr_dns_packet_code_t

Function Documentation

◆ fr_dns_attr_flags()

◆ fr_dns_decode()

◆ fr_dns_encode()

◆ fr_dns_flag_dns_label_any()

◆ fr_dns_global_free()

◆ fr_dns_global_init()

◆ fr_dns_labels_get()

◆ fr_dns_packet_ok()

Variable Documentation

◆ fr_dns_packet_names

◆ fr_dns_reason_fail_table

◆ fr_dns_reason_fail_table_len