This file contains helper functions for the validator module. More...

#include "util/rbtree.h"
#include "util/data/packed_rrset.h"
#include "sldns/rrdef.h"

Data Structures
struct	nsec3_cache_table
	Cache table for NSEC3 hashes. More...

struct	nsec3_cached_hash
	The NSEC3 hash result storage. More...

Macros
#define	NSEC3_OPTOUT 0x01

#define	NSEC3_UNKNOWN_FLAGS 0xFE
	The unknown flags in the NSEC3 flags field. More...

#define	NSEC3_HASH_SHA1 0x01
	The SHA1 hash algorithm for NSEC3.

Functions
enum sec_status	nsec3_prove_nameerror (struct module_env env, struct val_env ve, struct ub_packed_rrset_key *list, size_t num, struct query_info qinfo, struct key_entry_key kkey, struct nsec3_cache_table ct, int *calc)
	Determine if the set of NSEC3 records provided with a response prove NAME ERROR. More...

enum sec_status	nsec3_prove_nodata (struct module_env env, struct val_env ve, struct ub_packed_rrset_key *list, size_t num, struct query_info qinfo, struct key_entry_key kkey, struct nsec3_cache_table ct, int *calc)
	Determine if the NSEC3s provided in a response prove the NOERROR/NODATA status. More...

enum sec_status	nsec3_prove_wildcard (struct module_env env, struct val_env ve, struct ub_packed_rrset_key *list, size_t num, struct query_info qinfo, struct key_entry_key kkey, uint8_t wc, struct nsec3_cache_table ct, int calc)
	Prove that a positive wildcard match was appropriate (no direct match RRset). More...

enum sec_status	nsec3_prove_nods (struct module_env env, struct val_env ve, struct ub_packed_rrset_key *list, size_t num, struct query_info qinfo, struct key_entry_key kkey, char reason, sldns_ede_code reason_bogus, struct module_qstate qstate, struct nsec3_cache_table ct, char *reasonbuf, size_t reasonlen)
	Prove that a DS response either had no DS, or wasn't a delegation point. More...

enum sec_status	nsec3_prove_nxornodata (struct module_env env, struct val_env ve, struct ub_packed_rrset_key *list, size_t num, struct query_info qinfo, struct key_entry_key kkey, int nodata, struct nsec3_cache_table ct, int calc)
	Prove NXDOMAIN or NODATA. More...

int	nsec3_hash_cmp (const void c1, const void c2)
	Rbtree for hash cache comparison function. More...

int	nsec3_cache_table_init (struct nsec3_cache_table ct, struct regional region)
	Initialise the NSEC3 cache table. More...

int	nsec3_hash_name (rbtree_type table, struct regional region, struct sldns_buffer buf, struct ub_packed_rrset_key nsec3, int rr, uint8_t dname, size_t dname_len, struct nsec3_cached_hash *hash)
	Obtain the hash of an owner name. More...

size_t	nsec3_get_nextowner_b32 (struct ub_packed_rrset_key rrset, int r, uint8_t buf, size_t max)
	Get next owner name, converted to base32 encoding and with the zone name (taken from the nsec3 owner name) appended. More...

size_t	nsec3_hash_to_b32 (uint8_t hash, size_t hashlen, uint8_t zone, size_t zonelen, uint8_t *buf, size_t max)
	Convert hash into base32 encoding and with the zone name appended. More...

int	nsec3_get_params (struct ub_packed_rrset_key rrset, int r, int algo, size_t iter, uint8_t salt, size_t saltlen)
	Get NSEC3 parameters out of rr. More...

size_t	nsec3_get_hashed (struct sldns_buffer buf, uint8_t nm, size_t nmlen, int algo, size_t iter, uint8_t salt, size_t saltlen, uint8_t res, size_t max)
	Get NSEC3 hashed in a buffer. More...

int	nsec3_has_type (struct ub_packed_rrset_key *rrset, int r, uint16_t type)
	see if NSEC3 RR contains given type More...

int	nsec3_has_optout (struct ub_packed_rrset_key *rrset, int r)
	return if nsec3 RR has the optout flag More...

int	nsec3_get_nextowner (struct ub_packed_rrset_key rrset, int r, uint8_t next, size_t nextlen)
	Return nsec3 RR next hashed owner name. More...

int	nsec3_covers (uint8_t zone, struct nsec3_cached_hash hash, struct ub_packed_rrset_key rrset, int rr, struct sldns_buffer buf)
	nsec3Covers Given a hash and a candidate NSEC3Record, determine if that NSEC3Record covers the hash. More...

Detailed Description

This file contains helper functions for the validator module.

The functions help with NSEC3 checking, the different NSEC3 proofs for denial of existence, and proofs for presence of types.

NSEC3 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hash Alg. | Flags | Iterations | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Salt Length | Salt / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hash Length | Next Hashed Owner Name / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ / Type Bit Maps / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

NSEC3PARAM 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hash Alg. | Flags | Iterations | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Salt Length | Salt / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Macro Definition Documentation

◆ NSEC3_OPTOUT

#define NSEC3_OPTOUT 0x01

0 1 2 3 4 5 6 7

+-+-+-+-+-+-+-+-+ | |O| +-+-+-+-+-+-+-+-+ The OPT-OUT bit in the NSEC3 flags field. If enabled, there can be zero or more unsigned delegations in the span. If disabled, there are zero unsigned delegations in the span.

◆ NSEC3_UNKNOWN_FLAGS

#define NSEC3_UNKNOWN_FLAGS 0xFE

The unknown flags in the NSEC3 flags field.

They must be zero, or the NSEC3 is ignored.

Function Documentation

◆ nsec3_prove_nameerror()

enum sec_status nsec3_prove_nameerror	(	struct module_env *	env,
		struct val_env *	ve,
		struct ub_packed_rrset_key **	list,
		size_t	num,
		struct query_info *	qinfo,
		struct key_entry_key *	kkey,
		struct nsec3_cache_table *	ct,
		int *	calc
	)

Determine if the set of NSEC3 records provided with a response prove NAME ERROR.

This means that the NSEC3s prove a) the closest encloser exists, b) the direct child of the closest encloser towards qname doesn't exist, and c) *.closest encloser does not exist.

Parameters

env	module environment with temporary region and buffer.
ve	validator environment, with iteration count settings.
list	array of RRsets, some of which are NSEC3s.
num	number of RRsets in the array to examine.
qinfo	query that is verified for.
kkey	key entry that signed the NSEC3s.
ct	cached hashes table.
calc	current hash calculations.

Returns: : sec_status SECURE of the Name Error is proven by the NSEC3 RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored, UNCHECKED if no more hash calculations are allowed at this point.

◆ nsec3_prove_nodata()

enum sec_status nsec3_prove_nodata	(	struct module_env *	env,
		struct val_env *	ve,
		struct ub_packed_rrset_key **	list,
		size_t	num,
		struct query_info *	qinfo,
		struct key_entry_key *	kkey,
		struct nsec3_cache_table *	ct,
		int *	calc
	)

Determine if the NSEC3s provided in a response prove the NOERROR/NODATA status.

There are a number of different variants to this:

1) Normal NODATA – qname is matched to an NSEC3 record, type is not present.

2) ENT NODATA – because there must be NSEC3 record for empty-non-terminals, this is the same as #1.

3) NSEC3 ownername NODATA – qname matched an existing, lone NSEC3 ownername, but qtype was not NSEC3. NOTE: as of nsec-05, this case no longer exists.

4) Wildcard NODATA – A wildcard matched the name, but not the type.

5) Opt-In DS NODATA – the qname is covered by an opt-in span and qtype == DS. (or maybe some future record with the same parent-side-only property)

Parameters

env	module environment with temporary region and buffer.
ve	validator environment, with iteration count settings.
list	array of RRsets, some of which are NSEC3s.
num	number of RRsets in the array to examine.
qinfo	query that is verified for.
kkey	key entry that signed the NSEC3s.
ct	cached hashes table.
calc	current hash calculations.

Returns: : sec_status SECURE of the proposition is proven by the NSEC3 RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored, UNCHECKED if no more hash calculations are allowed at this point.

◆ nsec3_prove_wildcard()

enum sec_status nsec3_prove_wildcard	(	struct module_env *	env,
		struct val_env *	ve,
		struct ub_packed_rrset_key **	list,
		size_t	num,
		struct query_info *	qinfo,
		struct key_entry_key *	kkey,
		uint8_t *	wc,
		struct nsec3_cache_table *	ct,
		int *	calc
	)

Prove that a positive wildcard match was appropriate (no direct match RRset).

Parameters

env	module environment with temporary region and buffer.
ve	validator environment, with iteration count settings.
list	array of RRsets, some of which are NSEC3s.
num	number of RRsets in the array to examine.
qinfo	query that is verified for.
kkey	key entry that signed the NSEC3s.
wc	The purported wildcard that matched. This is the wildcard name as .wildcard.name., with the . label already removed.
ct	cached hashes table.
calc	current hash calculations.

Returns: : sec_status SECURE of the proposition is proven by the NSEC3 RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored, UNCHECKED if no more hash calculations are allowed at this point.

◆ nsec3_prove_nods()

enum sec_status nsec3_prove_nods	(	struct module_env *	env,
		struct val_env *	ve,
		struct ub_packed_rrset_key **	list,
		size_t	num,
		struct query_info *	qinfo,
		struct key_entry_key *	kkey,
		char **	reason,
		sldns_ede_code *	reason_bogus,
		struct module_qstate *	qstate,
		struct nsec3_cache_table *	ct,
		char *	reasonbuf,
		size_t	reasonlen
	)

Prove that a DS response either had no DS, or wasn't a delegation point.

Fundamentally there are two cases here: normal NODATA and Opt-In NODATA.

Parameters

env	module environment with temporary region and buffer.
ve	validator environment, with iteration count settings.
list	array of RRsets, some of which are NSEC3s.
num	number of RRsets in the array to examine.
qinfo	query that is verified for.
kkey	key entry that signed the NSEC3s.
reason	string for bogus result.
reason_bogus	EDE (RFC8914) code paired with the reason of failure.
qstate	qstate with region.
ct	cached hashes table.
reasonbuf	buffer to use for fail reason string print.
reasonlen	length of reasonbuf.

Returns: : sec_status SECURE of the proposition is proven by the NSEC3 RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored. or if there was no DS in an insecure (i.e., opt-in) way, INDETERMINATE if it was clear that this wasn't a delegation point, UNCHECKED if no more hash calculations are allowed at this point.

◆ nsec3_prove_nxornodata()

enum sec_status nsec3_prove_nxornodata	(	struct module_env *	env,
		struct val_env *	ve,
		struct ub_packed_rrset_key **	list,
		size_t	num,
		struct query_info *	qinfo,
		struct key_entry_key *	kkey,
		int *	nodata,
		struct nsec3_cache_table *	ct,
		int *	calc
	)

Prove NXDOMAIN or NODATA.

Parameters

env	module environment with temporary region and buffer.
ve	validator environment, with iteration count settings.
list	array of RRsets, some of which are NSEC3s.
num	number of RRsets in the array to examine.
qinfo	query that is verified for.
kkey	key entry that signed the NSEC3s.
nodata	if return value is secure, this indicates if nodata or nxdomain was proven.
ct	cached hashes table.
calc	current hash calculations.

Returns: : sec_status SECURE of the proposition is proven by the NSEC3 RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly ignored, UNCHECKED if no more hash calculations are allowed at this point.

◆ nsec3_hash_cmp()

int nsec3_hash_cmp	(	const void *	c1,
		const void *	c2
	)

Rbtree for hash cache comparison function.

Parameters

c1	key 1.
c2	key 2.

Returns: : comparison code, -1, 0, 1, of the keys.

References nsec3_cached_hash::dname, nsec3_cached_hash::nsec3, nsec3_get_algo(), nsec3_get_iter(), nsec3_get_salt(), query_dname_compare(), and nsec3_cached_hash::rr.

Referenced by nsec3_cache_table_init().

◆ nsec3_cache_table_init()

int nsec3_cache_table_init	(	struct nsec3_cache_table *	ct,
		struct regional *	region
	)

Initialise the NSEC3 cache table.

Parameters

ct	the nsec3 cache table.
region	the region where allocations for the table will happen.

Returns: true on success, false on malloc error.

References nsec3_hash_cmp(), rbtree_init(), and regional_alloc().

◆ nsec3_hash_name()

int nsec3_hash_name	(	rbtree_type *	table,
		struct regional *	region,
		struct sldns_buffer *	buf,
		struct ub_packed_rrset_key *	nsec3,
		int	rr,
		uint8_t *	dname,
		size_t	dname_len,
		struct nsec3_cached_hash **	hash
	)

Obtain the hash of an owner name.

Used internally by the nsec3 proof functions in this file. published to enable unit testing of hash algorithms and cache.

Parameters

table	the cache table. Must be initialised at start.
region	scratch region to use for allocation. This region holds the tree, if you wipe the region, reinit the tree.
buf	temporary buffer.
nsec3	the rrset with parameters
rr	rr number from d that has the NSEC3 parameters to hash to.
dname	name to hash This pointer is used inside the tree, assumed region-alloced.
dname_len	the length of the name.
hash	the hash node is returned on success.

Returns: : 2 on success, hash from cache is returned. 1 on success, newly computed hash is returned. 0 on a malloc failure. -1 if the NSEC3 rr was badly formatted (i.e. formerr).

References nsec3_cached_hash::dname, nsec3_cached_hash::dname_len, nsec3_cached_hash::hash, rbnode_type::key, log_assert, nsec3_cached_hash::node, nsec3_cached_hash::nsec3, nsec3_calc_b32(), nsec3_calc_hash(), rbtree_insert(), rbtree_search(), regional_alloc(), and nsec3_cached_hash::rr.

Referenced by find_covering_nsec3(), and find_matching_nsec3().

◆ nsec3_get_nextowner_b32()

size_t nsec3_get_nextowner_b32	(	struct ub_packed_rrset_key *	rrset,
		int	r,
		uint8_t *	buf,
		size_t	max
	)

Get next owner name, converted to base32 encoding and with the zone name (taken from the nsec3 owner name) appended.

Parameters

rrset	the NSEC3 rrset.
r	the rr num of the nsec3 in the rrset.
buf	buffer to store name in
max	size of buffer.

Returns: length of name on success. 0 on failure (buffer too short or bad format nsec3 record).

References packed_rrset_key::dname, packed_rrset_key::dname_len, dname_remove_label(), nsec3_get_nextowner(), nsec3_hash_to_b32(), and ub_packed_rrset_key::rk.

◆ nsec3_hash_to_b32()

size_t nsec3_hash_to_b32	(	uint8_t *	hash,
		size_t	hashlen,
		uint8_t *	zone,
		size_t	zonelen,
		uint8_t *	buf,
		size_t	max
	)

Convert hash into base32 encoding and with the zone name appended.

Parameters

hash	hashed buffer
hashlen	length of hash
zone	name of zone
zonelen	length of zonename.
buf	buffer to store name in
max	size of buffer.

Returns: length of name on success. 0 on failure (buffer too short or bad format nsec3 record).

References sldns_b32_ntop_extended_hex().

Referenced by neg_nsec3_getnc(), and nsec3_get_nextowner_b32().

◆ nsec3_get_params()

int nsec3_get_params	(	struct ub_packed_rrset_key *	rrset,
		int	r,
		int *	algo,
		size_t *	iter,
		uint8_t **	salt,
		size_t *	saltlen
	)

Get NSEC3 parameters out of rr.

Parameters

rrset	the NSEC3 rrset.
r	the rr num of the nsec3 in the rrset.
algo	nsec3 hash algo.
iter	iteration count.
salt	ptr to salt inside rdata.
saltlen	length of salt.

Returns: 0 if bad formatted, unknown nsec3 hash algo, or unknown flags set.

References nsec3_get_algo(), nsec3_get_iter(), nsec3_get_salt(), nsec3_known_algo(), and nsec3_unknown_flags().

Referenced by neg_params_ok(), and nsec3_of_param_has_type().

◆ nsec3_get_hashed()

size_t nsec3_get_hashed	(	struct sldns_buffer *	buf,
		uint8_t *	nm,
		size_t	nmlen,
		int	algo,
		size_t	iter,
		uint8_t *	salt,
		size_t	saltlen,
		uint8_t *	res,
		size_t	max
	)

Get NSEC3 hashed in a buffer.

Parameters

buf	buffer for temp use.
nm	name to hash
nmlen	length of nm.
algo	algo to use, must be known.
iter	iterations
salt	salt for nsec3
saltlen	length of salt.
res	result of hash stored here.
max	maximum space for result.

Returns: 0 on failure, otherwise bytelength stored.

References nsec3_cached_hash::hash_len, log_err(), nsec3_hash_algo_size_supported(), query_dname_tolower(), secalgo_nsec3_hash(), sldns_buffer_begin(), sldns_buffer_clear(), sldns_buffer_flip(), sldns_buffer_limit(), and sldns_buffer_write().

◆ nsec3_has_type()

int nsec3_has_type	(	struct ub_packed_rrset_key *	rrset,
		int	r,
		uint16_t	type
	)

see if NSEC3 RR contains given type

Parameters

rrset	NSEC3 rrset
r	RR in rrset
type	in host order to check bit for.

Returns: true if bit set, false if not or error.

References packed_rrset_data::count, lruhash_entry::data, ub_packed_rrset_key::entry, log_assert, nsecbitmap_has_type_rdata(), packed_rrset_data::rr_data, and packed_rrset_data::rr_len.

Referenced by nsec3_no_type(), and nsec3_of_param_has_type().

◆ nsec3_has_optout()

int nsec3_has_optout	(	struct ub_packed_rrset_key *	rrset,
		int	r
	)

return if nsec3 RR has the optout flag

Parameters

rrset	NSEC3 rrset
r	RR in rrset

Returns: true if optout, false on error or not optout

References packed_rrset_data::count, lruhash_entry::data, ub_packed_rrset_key::entry, log_assert, NSEC3_OPTOUT, packed_rrset_data::rr_data, and packed_rrset_data::rr_len.

◆ nsec3_get_nextowner()

int nsec3_get_nextowner	(	struct ub_packed_rrset_key *	rrset,
		int	r,
		uint8_t **	next,
		size_t *	nextlen
	)

Return nsec3 RR next hashed owner name.

Parameters

rrset	NSEC3 rrset
r	RR in rrset
next	ptr into rdata to next owner hash
nextlen	length of hash.

Returns: false on malformed

References packed_rrset_data::count, lruhash_entry::data, ub_packed_rrset_key::entry, log_assert, packed_rrset_data::rr_data, and packed_rrset_data::rr_len.

Referenced by nsec3_covers(), and nsec3_get_nextowner_b32().

◆ nsec3_covers()

int nsec3_covers	(	uint8_t *	zone,
		struct nsec3_cached_hash *	hash,
		struct ub_packed_rrset_key *	rrset,
		int	rr,
		struct sldns_buffer *	buf
	)

nsec3Covers Given a hash and a candidate NSEC3Record, determine if that NSEC3Record covers the hash.

Covers specifically means that the hash is in between the owner and next hashes and does not equal either.

Parameters

zone	the zone name.
hash	the hash of the name
rrset	the rrset of the NSEC3.
rr	which rr in the rrset.
buf	temporary buffer.

Returns: true if covers, false if not.

References packed_rrset_key::dname, nsec3_cached_hash::hash, label_compare_lower(), nsec3_get_nextowner(), query_dname_compare(), ub_packed_rrset_key::rk, nsec3_cached_hash::rr, sldns_b32_pton_extended_hex(), sldns_buffer_begin(), sldns_buffer_clear(), and sldns_buffer_limit().

Referenced by find_covering_nsec3().

Data Structures

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ NSEC3_OPTOUT

◆ NSEC3_UNKNOWN_FLAGS

Function Documentation

◆ nsec3_prove_nameerror()

◆ nsec3_prove_nodata()

◆ nsec3_prove_wildcard()

◆ nsec3_prove_nods()

◆ nsec3_prove_nxornodata()

◆ nsec3_hash_cmp()

◆ nsec3_cache_table_init()

◆ nsec3_hash_name()

◆ nsec3_get_nextowner_b32()

◆ nsec3_hash_to_b32()

◆ nsec3_get_params()

◆ nsec3_get_hashed()

◆ nsec3_has_type()

◆ nsec3_has_optout()

◆ nsec3_get_nextowner()

◆ nsec3_covers()