This file contains domain name handling functions. More...

#include "config.h"
#include <ctype.h>
#include "util/data/dname.h"
#include "util/data/msgparse.h"
#include "util/log.h"
#include "util/storage/lookup3.h"

Functions
size_t	query_dname_len (ldns_buffer *query)
	Determine length of dname in buffer, no compression ptrs allowed,.
size_t	dname_valid (uint8_t *dname, size_t maxlen)
	Determine if dname in memory is correct.
int	query_dname_compare (register uint8_t d1, register uint8_t d2)
	compare uncompressed, noncanonical, registers are hints for speed
void	query_dname_tolower (uint8_t *dname)
	lowercase query dname
void	pkt_dname_tolower (ldns_buffer pkt, uint8_t dname)
	lowercase pkt dname (follows compression pointers)
size_t	pkt_dname_len (ldns_buffer *pkt)
	Determine correct, compressed, dname present in packet.
int	dname_pkt_compare (ldns_buffer pkt, uint8_t d1, uint8_t *d2)
	Compare dnames in packet (compressed).
hashvalue_t	dname_query_hash (uint8_t *dname, hashvalue_t h)
	Hash dname, label by label, lowercasing, into hashvalue.
hashvalue_t	dname_pkt_hash (ldns_buffer pkt, uint8_t dname, hashvalue_t h)
	Hash dname, label by label, lowercasing, into hashvalue.
void	dname_pkt_copy (ldns_buffer pkt, uint8_t to, uint8_t *dname)
	Copy over a valid dname and decompress it.
void	dname_print (FILE out, ldns_buffer pkt, uint8_t *dname)
	Debug helper.
int	dname_count_labels (uint8_t *dname)
	Count the number of labels in an uncompressed dname in memory.
int	dname_count_size_labels (uint8_t dname, size_t size)
	Count labels and dname length both, for uncompressed dname in memory.
static int	memlowercmp (uint8_t p1, uint8_t p2, uint8_t len)
	Compare labels in memory, lowercase while comparing.
int	dname_lab_cmp (uint8_t d1, int labs1, uint8_t d2, int labs2, int *mlabs)
	Compare dnames, sorted not canonical, but by label.
int	dname_buffer_write (ldns_buffer pkt, uint8_t dname)
	Copy over a valid dname to a packet.
void	dname_str (uint8_t dname, char str)
	Debug helper.
int	dname_strict_subdomain (uint8_t d1, int labs1, uint8_t d2, int labs2)
	See if domain name d1 is a strict subdomain of d2.
int	dname_strict_subdomain_c (uint8_t d1, uint8_t d2)
	Like dname_strict_subdomain but counts labels.
int	dname_subdomain_c (uint8_t d1, uint8_t d2)
	Counts labels.
int	dname_is_root (uint8_t *dname)
	Returns true if the uncompressed wireformat dname is the root ".".
void	dname_remove_label (uint8_t *dname, size_t len)
	Snip off first label from a dname, returning the parent zone.
void	dname_remove_labels (uint8_t *dname, size_t len, int n)
	Snip off first N labels from a dname, returning the parent zone.
int	dname_signame_label_count (uint8_t *dname)
	Count labels for the RRSIG signature label field.
int	dname_is_wild (uint8_t *dname)
	Return true if the label is a wildcard, *.example.com.
static int	memcanoncmp (uint8_t p1, uint8_t len1, uint8_t p2, uint8_t len2)
	Compare labels in memory, lowercase while comparing.
int	dname_canon_lab_cmp (uint8_t d1, int labs1, uint8_t d2, int labs2, int *mlabs)
	Compare dnames, Canonical in rfc4034 sense, but by label.
int	dname_canonical_compare (uint8_t d1, uint8_t d2)
	Canonical dname compare.
uint8_t *	dname_get_shared_topdomain (uint8_t d1, uint8_t d2)
	Get the shared topdomain between two names.

Detailed Description

This file contains domain name handling functions.

Function Documentation

size_t query_dname_len ( ldns_buffer * query )

Determine length of dname in buffer, no compression ptrs allowed,.

Parameters:

query,: the ldns buffer, current position at start of dname. at end, position is at end of the dname.

Returns:: : 0 on parse failure, or length including ending 0 of dname.

Referenced by chaos_replystr(), dname_test_qdl(), and query_info_parse().

size_t dname_valid	(	uint8_t *	dname,
		size_t	len
	)

Determine if dname in memory is correct.

no compression ptrs allowed.

Parameters:

dname,:	where dname starts in memory.
len,:	dname is not allowed to exceed this length (i.e. of allocation).

Returns:: length of dname if dname is ok, 0 on a parse error.

Referenced by delegpt_rrset_add_ns(), sanitize_nsec_is_overreach(), dname_test_valid(), get_cname_target(), wipeout(), nsec_has_type(), nsec_get_next(), canonicalize_rdata(), dnskey_verify_rrset_sig(), and rrsig_get_signer().

void pkt_dname_tolower	(	ldns_buffer *	pkt,
		uint8_t *	dname
	)

lowercase pkt dname (follows compression pointers)

Parameters:

pkt,:	the packet, used to follow compression pointers. Position is unchanged.
dname,:	start of dname in packet.

References LABEL_IS_PTR, PTR_OFFSET, and MAX_COMPRESS_PTRS.

Referenced by serviced_callbacks(), and dname_test_pdtl().

size_t pkt_dname_len ( ldns_buffer * pkt )

Determine correct, compressed, dname present in packet.

Checks for parse errors.

Parameters:

pkt,: packet to read from (from current start position).

Returns:: : 0 on parse error. At exit the position is right after the (compressed) dname. Compression pointers are followed and checked for loops. The uncompressed wireformat length is returned.

References LABEL_IS_PTR, PTR_OFFSET, and MAX_COMPRESS_PTRS.

Referenced by get_additional_name(), analyze_dname(), dname_test_pkt_dname_len(), nsec_at_apex(), parse_query_section(), calc_size(), parse_section(), parse_edns_from_pkt(), and rdata_copy().

int dname_pkt_compare	(	ldns_buffer *	pkt,
		uint8_t *	d1,
		uint8_t *	d2
	)

Compare dnames in packet (compressed).

Dnames must be valid. routine performs lowercasing, so the packet casing is preserved.

Parameters:

pkt,:	packet, used to resolve compression pointers.
d1,:	dname to compare
d2,:	dname to compare

Returns:: : -1, 0, or +1 depending on comparison results. Sort order is first difference found. not the canonical ordering.

References log_assert, LABEL_IS_PTR, and PTR_OFFSET.

Referenced by scrub_normalize(), scrub_sanitize(), scrub_message(), smart_compare(), and rrset_parse_equals().

hashvalue_t dname_query_hash	(	uint8_t *	dname,
		hashvalue_t	h
	)

Hash dname, label by label, lowercasing, into hashvalue.

Dname in query format (not compressed).

Parameters:

dname,:	dname to hash.
h,:	initial hash value.

Returns:: : result hash value.

References log_assert.

Referenced by hash_infra(), query_info_hash(), rrset_key_hash(), and key_entry_hash().

hashvalue_t dname_pkt_hash	(	ldns_buffer *	pkt,
		uint8_t *	dname,
		hashvalue_t	h
	)

Hash dname, label by label, lowercasing, into hashvalue.

Dname in pkt format (compressed).

Parameters:

pkt,:	packet, for resolving compression pointers.
dname,:	dname to hash, pointer to the pkt buffer. Must be valid format. No loops, etc.
h,:	initial hash value.

Returns:: : result hash value. Result is the same as dname_query_hash, even if compression is used.

References LABEL_IS_PTR, PTR_OFFSET, and log_assert.

Referenced by pkt_hash_rrset(), and pkt_hash_rrset_first().

void dname_pkt_copy	(	ldns_buffer *	pkt,
		uint8_t *	to,
		uint8_t *	dname
	)

Copy over a valid dname and decompress it.

Parameters:

pkt,:	packet to resolve compression pointers.
to,:	buffer of size from pkt_len function to hold result.
dname,:	pointer into packet where dname starts.

References LABEL_IS_PTR, PTR_OFFSET, log_assert, and log_err().

Referenced by priv_lookup_name(), remove_rrset(), synth_cname(), synth_cname_rrset(), pkt_strict_sub(), pkt_sub(), sub_of_pkt(), parse_create_qinfo(), rdata_copy(), and parse_copy_decompress_rrset().

void dname_print	(	FILE *	out,
		ldns_buffer *	pkt,
		uint8_t *	dname
	)

Debug helper.

Print wireformat dname to output.

Parameters:

out,:	like stdout or a file.
pkt,:	if not NULL, the packet for resolving compression ptrs.
dname,:	pointer to (start of) dname.

References LABEL_IS_PTR, and PTR_OFFSET.

Referenced by analyze_dname(), print_neg_cache(), and parse_section().

int dname_count_labels ( uint8_t * dname )

Count the number of labels in an uncompressed dname in memory.

Parameters:

dname,: pointer to uncompressed dname.

Returns:: : count of labels, including root label, "com." has 2 labels.

Referenced by iter_msg_from_zone(), local_zones_answer(), dname_test_count_labels(), dname_strict_subdomain_c(), dname_subdomain_c(), dname_canonical_compare(), dname_get_shared_topdomain(), packed_rrset_encode(), insert_query(), autr_tp_create(), find_add_tp(), set_next_probe(), anchors_lookup(), neg_find_zone(), neg_create_zone(), wipeout(), neg_insert_data(), val_neg_dlvlookup(), val_neg_getmsg(), nsec_closest_encloser(), val_nsec_proves_no_wc(), dlv_topdomain(), next_closer(), val_find_best_signer(), val_rrset_wildcard(), and processFindKey().

int dname_count_size_labels	(	uint8_t *	dname,
		size_t *	size
	)

Count labels and dname length both, for uncompressed dname in memory.

Parameters:

dname,:	pointer to uncompressed dname.
size,:	length of dname, including root label.

Returns:: : count of labels, including root label, "com." has 2 labels.

Referenced by parse_arg_name(), delegpt_set_name(), delegpt_add_ns(), make_stub_holes(), forwards_lookup(), forwards_delete_zone(), hints_lookup_stub(), read_names(), priv_lookup_name(), parse_dname(), lz_enter_rr_into_zone(), lz_enter_rr_str(), lz_setup_implicit(), local_zones_add_RR(), write_q(), dname_test_count_size_labels(), compress_rdata(), anchor_store_new_key(), wipeout(), nsec3_prove_wildcard(), and val_find_best_signer().

static int memlowercmp	(	uint8_t *	p1,
		uint8_t *	p2,
		uint8_t	len
	)		`[static]`

Compare labels in memory, lowercase while comparing.

Parameters:

p1,:	label 1
p2,:	label 2
len,:	number of bytes to compare.

Returns:: : 0, -1, +1 comparison result.

Referenced by memcanoncmp().

int dname_lab_cmp	(	uint8_t *	d1,
		int	labs1,
		uint8_t *	d2,
		int	labs2,
		int *	mlabs
	)

Compare dnames, sorted not canonical, but by label.

Such that zone contents follows zone apex.

Parameters:

d1,:	first dname. pointer to uncompressed wireformat.
labs1,:	number of labels in first dname.
d2,:	second dname. pointer to uncompressed wireformat.
labs2,:	number of labels in second dname.
mlabs,:	number of labels that matched exactly (the shared topdomain).

Returns:: : 0 for equal, -1 smaller, or +1 d1 larger than d2.

References log_assert.

Referenced by fwd_cmp(), fwd_init_parents(), forwards_lookup(), local_zone_cmp(), init_parents(), lz_setup_implicit(), local_zones_lookup(), dname_test_dname_lab_cmp(), dname_strict_subdomain(), dname_subdomain_c(), dname_get_shared_topdomain(), compress_tree_search(), name_tree_compare(), name_tree_init_parents(), name_tree_lookup(), anchor_cmp(), anchors_init_parents_locked(), anchors_lookup(), neg_closest_zone_parent(), neg_closest_data_parent(), and val_find_best_signer().

int dname_buffer_write	(	ldns_buffer *	pkt,
		uint8_t *	dname
	)

Copy over a valid dname to a packet.

Parameters:

pkt,:	packet to copy to.
dname,:	dname to copy.

Returns:: : 0 if not enough space in buffer.

Referenced by compress_any_dname().

void dname_str	(	uint8_t *	dname,
		char *	str
	)

Debug helper.

Print dname to given string buffer (string buffer must be at least 255 chars + 1 for the 0, in printable form. This may lose information (? for nonprintable characters, or & if the name is too long, # for a bad label length).

Parameters:

dname,:	uncompressed wireformat.
str,:	buffer of 255+1 length.

Referenced by print_deleg_lookup(), ssl_print_name_dp(), get_mesh_status(), do_dump_requestlist(), dump_infra_host(), do_list_local_zones(), delegpt_log(), fill_canon(), serviced_perturb_qname(), outnet_serviced_query(), print_neg_cache(), errinf_to_str(), errinf_rrset(), errinf_dname(), log_nametypeclass(), log_name_addr(), autr_debug_print_tp(), and anchors_assemble_rrsets().

int dname_strict_subdomain	(	uint8_t *	d1,
		int	labs1,
		uint8_t *	d2,
		int	labs2
	)

See if domain name d1 is a strict subdomain of d2.

That is a subdomain, but not equal.

Parameters:

d1,:	domain name, uncompressed wireformat
labs1,:	number of labels in d1, including root label.
d2,:	domain name, uncompressed wireformat
labs2,:	number of labels in d2, including root label.

Returns:: true if d1 is a subdomain of d2, but not equal to d2.

References dname_lab_cmp().

Referenced by hints_lookup_stub(), iter_msg_from_zone(), set_kiddo_parents(), is_terminal(), dname_test_strict_subdomain(), and dname_strict_subdomain_c().

int dname_strict_subdomain_c	(	uint8_t *	d1,
		uint8_t *	d2
	)

Like dname_strict_subdomain but counts labels.

Parameters:

d1,:	domain name, uncompressed wireformat
d2,:	domain name, uncompressed wireformat

Returns:: true if d1 is a subdomain of d2, but not equal to d2.

References dname_strict_subdomain(), and dname_count_labels().

Referenced by response_type_from_server(), pkt_strict_sub(), handle_cname_response(), processQueryResponse(), nsec_proves_nodata(), val_nsec_proves_name_error(), val_nsec_proves_insecuredelegation(), val_nsec_check_dlv(), and processInit().

int dname_subdomain_c	(	uint8_t *	d1,
		uint8_t *	d2
	)

Counts labels.

Tests is d1 is a subdomain of d2.

Parameters:

d1,:	domain name, uncompressed wireformat
d2,:	domain name, uncompressed wireformat

Returns:: true if d1 is a subdomain of d2.

References dname_count_labels(), and dname_lab_cmp().

Referenced by zone_del_rrset(), zone_del_msg(), zone_del_kcache(), response_type_from_server(), pkt_sub(), sub_of_pkt(), sanitize_nsec_is_overreach(), iter_dp_is_useless(), iter_scrub_ds(), generate_parentside_target_query(), processQueryResponse(), dname_test_subdomain(), sum_subtree_inuse(), sum_zone_subtree_inuse(), wipeout(), val_neg_addreply(), val_neg_addreferral(), val_neg_getmsg(), val_nsec_proves_name_error(), val_nsec_proves_insecuredelegation(), filter_init(), nsec3_find_closest_encloser(), dnskey_verify_rrset_sig(), val_find_best_signer(), val_mark_insecure(), processInit(), processFindKey(), val_dlv_init(), processDLVLookup(), and process_dlv_response().

int dname_is_root ( uint8_t * dname )

Returns true if the uncompressed wireformat dname is the root ".".

Parameters:

dname,: the dname to check

Returns:: true if ".", false if not.

References log_assert, and LABEL_IS_PTR.

Referenced by print_deleg_lookup(), forwards_next_root(), prime_stub(), forward_request(), processInitRequest(), dns_cache_lookup(), del_empty_term(), dname_test_isroot(), check_data(), check_zone_invariants(), name_tree_next_root(), key_cache_obtain(), calc_data_need(), calc_zone_need(), nsec_proves_nodata(), filter_init(), and nsec3_do_prove_nodata().

void dname_remove_label	(	uint8_t **	dname,
		size_t *	len
	)

Snip off first label from a dname, returning the parent zone.

Parameters:

dname,:	from what to strip off. uncompressed wireformat.
len,:	length, adjusted to become less.

Returns:: stripped off, or "." if input was ".".

References log_assert, and LABEL_IS_PTR.

Referenced by print_deleg_lookup(), need_hole_insert(), prime_stub(), forward_request(), processInitRequest(), dns_cache_lookup(), lz_find_create_node(), del_empty_term(), dname_test_removelabel(), dname_remove_labels(), key_cache_obtain(), calc_data_need(), calc_zone_need(), neg_zone_chain(), neg_data_chain(), neg_find_nsec3_ce(), val_neg_getmsg(), nsec_proves_nodata(), val_nsec_check_dlv(), nsec3_get_nextowner_b32(), filter_next(), filter_init(), nsec3_find_closest_encloser(), insert_can_owner(), processInit(), val_dlv_init(), and processDLVLookup().

void dname_remove_labels	(	uint8_t **	dname,
		size_t *	len,
		int	n
	)

Snip off first N labels from a dname, returning the parent zone.

Parameters:

dname,:	from what to strip off. uncompressed wireformat.
len,:	length, adjusted to become less.
n,:	number of labels to strip off (from the left). if 0, nothing happens.

Returns:: stripped off, or "." if input was ".".

References dname_remove_label().

Referenced by lz_setup_implicit(), dname_get_shared_topdomain(), val_nsec_proves_no_wc(), dlv_topdomain(), next_closer(), val_rrset_wildcard(), and processFindKey().

int dname_signame_label_count ( uint8_t * dname )

Count labels for the RRSIG signature label field.

Like a normal labelcount, but "*" wildcard and "." root are not counted.

Parameters:

dname,: valid uncompressed wireformat.

Returns:: number of labels like in RRSIG; '*' and '.' are not counted.

Referenced by dname_test_sigcount(), insert_can_owner(), and dnskey_verify_rrset_sig().

int dname_is_wild ( uint8_t * dname )

Return true if the label is a wildcard, *.example.com.

Parameters:

dname,: valid uncompressed wireformat.

Returns:: true if wildcard, or false.

Referenced by dname_test_iswild(), val_nsec_prove_nodata_dsreply(), nsec_proves_nodata(), and val_rrset_wildcard().

static int memcanoncmp	(	uint8_t *	p1,
		uint8_t	len1,
		uint8_t *	p2,
		uint8_t	len2
	)		`[static]`

Compare labels in memory, lowercase while comparing.

Returns canonical order for labels. If all is equal, the shortest is first.

Parameters:

p1,:	label 1
len1,:	length of label 1.
p2,:	label 2
len2,:	length of label 2.

Returns:: : 0, -1, +1 comparison result.

References memlowercmp().

Referenced by dname_canon_lab_cmp().

int dname_canon_lab_cmp	(	uint8_t *	d1,
		int	labs1,
		uint8_t *	d2,
		int	labs2,
		int *	mlabs
	)

Compare dnames, Canonical in rfc4034 sense, but by label.

Such that zone contents follows zone apex.

Parameters:

d1,:	first dname. pointer to uncompressed wireformat.
labs1,:	number of labels in first dname.
d2,:	second dname. pointer to uncompressed wireformat.
labs2,:	number of labels in second dname.
mlabs,:	number of labels that matched exactly (the shared topdomain).

Returns:: : 0 for equal, -1 smaller, or +1 d1 larger than d2.

References log_assert, and memcanoncmp().

Referenced by local_data_cmp(), dname_canonical_compare(), val_neg_data_compare(), val_neg_zone_compare(), and wipeout().

int dname_canonical_compare	(	uint8_t *	d1,
		uint8_t *	d2
	)

Canonical dname compare.

Takes care of counting labels. Per rfc 4034 canonical order.

Parameters:

d1,:	first dname. pointer to uncompressed wireformat.
d2,:	second dname. pointer to uncompressed wireformat.

Returns:: : 0 for equal, -1 smaller, or +1 d1 larger than d2.

References dname_count_labels(), and dname_canon_lab_cmp().

Referenced by dname_test_canoncmp(), nsec_proves_nodata(), val_nsec_proves_name_error(), and val_nsec_check_dlv().

uint8_t* dname_get_shared_topdomain	(	uint8_t *	d1,
		uint8_t *	d2
	)

Get the shared topdomain between two names.

Root "." or longer.

Parameters:

d1,:	first dname. pointer to uncompressed wireformat.
d2,:	second dname. pointer to uncompressed wireformat.

Returns:: pointer to shared topdomain. Ptr to a part of d1.

References dname_count_labels(), dname_lab_cmp(), and dname_remove_labels().

Referenced by dname_test_topdomain(), nsec_closest_encloser(), and dlv_topdomain().

Functions

Detailed Description

Function Documentation