ncache.h File Reference

DNS Ncache. More...

#include <isc/lang.h>
#include <isc/stdtime.h>
#include <dns/types.h>

Go to the source code of this file.

Defines
#define	DNS_NCACHE_H   1
#define	DNS_NCACHETOWIRE_OMITDNSSEC   0x0001
	_OMITDNSSEC: Omit DNSSEC records when rendering.
Functions
isc_result_t	dns_ncache_add (dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node, dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t maxttl, dns_rdataset_t *addedrdataset)
isc_result_t	dns_ncache_addoptout (dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node, dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t maxttl, isc_boolean_t optout, dns_rdataset_t *addedrdataset)
	Convert the authority data from 'message' into a negative cache rdataset, and store it in 'cache' at 'node' with a TTL limited to 'maxttl'.
isc_result_t	dns_ncache_towire (dns_rdataset_t *rdataset, dns_compress_t *cctx, isc_buffer_t *target, unsigned int options, unsigned int *countp)
	Convert the negative caching rdataset 'rdataset' to wire format, compressing names as specified in 'cctx', and storing the result in 'target'. If 'omit_dnssec' is set, DNSSEC records will not be added to 'target'.
isc_result_t	dns_ncache_getrdataset (dns_rdataset_t *ncacherdataset, dns_name_t *name, dns_rdatatype_t type, dns_rdataset_t *rdataset)
	Search the negative caching rdataset for an rdataset with the specified name and type.
isc_result_t	dns_ncache_getsigrdataset (dns_rdataset_t *ncacherdataset, dns_name_t *name, dns_rdatatype_t covers, dns_rdataset_t *rdataset)
	Similar to dns_ncache_getrdataset() but get the rrsig that matches.
void	dns_ncache_current (dns_rdataset_t *ncacherdataset, dns_name_t *found, dns_rdataset_t *rdataset)
	Extract the current rdataset and name from a ncache entry.

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Detailed Description

DNS Ncache.

XXX TBS XXX

MP:

• The caller must ensure any required synchronization.

Reliability:

• No anticipated impact.

Resources:

• TBS

Security:

• No anticipated impact.

Standards:

• RFC2308

Definition in file ncache.h.

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Define Documentation

#define DNS_NCACHE_H   1

Definition at line 21 of file ncache.h.

#define DNS_NCACHETOWIRE_OMITDNSSEC   0x0001

_OMITDNSSEC: Omit DNSSEC records when rendering.

Definition at line 60 of file ncache.h.

Referenced by dns_ncache_towire(), and towiresorted().

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Function Documentation

isc_result_t dns_ncache_add	(	dns_message_t *	message,
		dns_db_t *	cache,
		dns_dbnode_t *	node,
		dns_rdatatype_t	covers,
		isc_stdtime_t	now,
		dns_ttl_t	maxttl,
		dns_rdataset_t *	addedrdataset
	)

Definition at line 101 of file ncache.c.

References addoptout(), and ISC_FALSE.

Referenced by ncache_adderesult().

isc_result_t dns_ncache_addoptout	(	dns_message_t *	message,
		dns_db_t *	cache,
		dns_dbnode_t *	node,
		dns_rdatatype_t	covers,
		isc_stdtime_t	now,
		dns_ttl_t	maxttl,
		isc_boolean_t	optout,
		dns_rdataset_t *	addedrdataset
	)

Convert the authority data from 'message' into a negative cache rdataset, and store it in 'cache' at 'node' with a TTL limited to 'maxttl'.

• dns_ncache_add produces a negative cache entry with a trust of no more than answer
• dns_ncache_addoptout produces a negative cache entry which will have a trust of secure if all the records that make up the entry are secure.

The 'covers' argument is the RR type whose nonexistence we are caching, or dns_rdatatype_any when caching a NXDOMAIN response.

'optout' indicates a DNS_RDATASETATTR_OPTOUT should be set.

Note:

• If 'addedrdataset' is not NULL, then it will be attached to the added rdataset. See dns_db_addrdataset() for more details.

Requires:

• 'message' is a valid message with a properly formatting negative cache authority section.

• The requirements of dns_db_addrdataset() apply to 'cache', 'node', 'now', and 'addedrdataset'.

Returns:

• ISC_R_SUCCESS
• ISC_R_NOSPACE

• Any result code of dns_db_addrdataset() is a possible result code of dns_ncache_add().

Definition at line 110 of file ncache.c.

References addoptout(), and ISC_TRUE.

Referenced by ncache_adderesult().

isc_result_t dns_ncache_towire	(	dns_rdataset_t *	rdataset,
		dns_compress_t *	cctx,
		isc_buffer_t *	target,
		unsigned int	options,
		unsigned int *	countp
	)

Convert the negative caching rdataset 'rdataset' to wire format, compressing names as specified in 'cctx', and storing the result in 'target'. If 'omit_dnssec' is set, DNSSEC records will not be added to 'target'.

Notes:

• The number of RRs added to target will be added to *countp.

Requires:

• 'rdataset' is a valid negative caching rdataset.

• 'rdataset' is not empty.

• 'countp' is a valid pointer.

Ensures:

• On a return of ISC_R_SUCCESS, 'target' contains a wire format for the data contained in 'rdataset'. Any error return leaves the buffer unchanged.

• *countp has been incremented by the number of RRs added to target.

Returns:

• ISC_R_SUCCESS - all ok
• ISC_R_NOSPACE - 'target' doesn't have enough room

• Any error returned by dns_rdata_towire(), dns_rdataset_next(), dns_name_towire().

Definition at line 273 of file ncache.c.

References dns_rdataset::attributes, isc_region::base, dns_rdata::data, DNS_COMPRESS_GLOBAL14, dns_compress_rollback(), dns_compress_setmethods(), dns_name_fromregion(), dns_name_init(), dns_name_towire(), DNS_NCACHETOWIRE_OMITDNSSEC, DNS_RDATA_INIT, dns_rdata_reset(), dns_rdata_towire(), dns_rdataset_current(), dns_rdataset_first(), dns_rdataset_next(), DNS_RDATASETATTR_NEGATIVE, dns_rdatatype_isdnssec(), INSIST, isc_buffer_add, isc_buffer_availableregion, isc_buffer_forward, isc_buffer_getuint16(), isc_buffer_init, isc_buffer_putuint16, isc_buffer_putuint32, isc_buffer_remaininglength, isc_buffer_remainingregion, ISC_R_NOMORE, ISC_R_NOSPACE, ISC_R_SUCCESS, dns_name::length, isc_region::length, dns_rdata::length, name, dns_rdataset::rdclass, dns_rdata::rdclass, REQUIRE, dns_rdataset::ttl, dns_rdata::type, dns_rdataset::type, and isc_buffer::used.

Referenced by towiresorted().

isc_result_t dns_ncache_getrdataset	(	dns_rdataset_t *	ncacherdataset,
		dns_name_t *	name,
		dns_rdatatype_t	type,
		dns_rdataset_t *	rdataset
	)

Search the negative caching rdataset for an rdataset with the specified name and type.

Requires:

• 'ncacherdataset' is a valid negative caching rdataset.

• 'ncacherdataset' is not empty.

• 'name' is a valid name.

• 'type' is not SIG, or a meta-RR type.

• 'rdataset' is a valid disassociated rdataset.

Ensures:

• On a return of ISC_R_SUCCESS, 'rdataset' is bound to the found rdataset.

Returns:

• ISC_R_SUCCESS - the rdataset was found.
• ISC_R_NOTFOUND - the rdataset was not found.

Definition at line 511 of file ncache.c.

References dns_rdataset::attributes, isc_region::base, dns_rdataset::covers, dns_rdata::data, dns_name_equal(), dns_name_fromregion(), dns_name_init(), DNS_RDATA_INIT, dns_rdata_reset(), dns_rdataset_clone(), dns_rdataset_current(), dns_rdataset_disassociate(), dns_rdataset_first(), dns_rdataset_init(), dns_rdataset_isassociated(), dns_rdataset_next(), DNS_RDATASETATTR_NEGATIVE, dns_trust_none, dns_trust_ultimate, INSIST, isc_buffer_add, isc_buffer_forward, isc_buffer_getuint16(), isc_buffer_getuint8(), isc_buffer_init, isc_buffer_remainingregion, ISC_R_NOMORE, ISC_R_NOTFOUND, ISC_R_SUCCESS, dns_name::length, isc_region::length, dns_rdata::length, dns_rdataset::methods, dns_rdataset::private1, dns_rdataset::private2, dns_rdataset::private3, dns_rdataset::private5, dns_rdataset::private6, dns_rdataset::privateuint4, dns_rdataset::rdclass, REQUIRE, dns_rdataset::trust, dns_rdataset::ttl, and dns_rdataset::type.

Referenced by isdelegation(), and warn_rfc1918().

isc_result_t dns_ncache_getsigrdataset	(	dns_rdataset_t *	ncacherdataset,
		dns_name_t *	name,
		dns_rdatatype_t	covers,
		dns_rdataset_t *	rdataset
	)

Similar to dns_ncache_getrdataset() but get the rrsig that matches.

Definition at line 585 of file ncache.c.

References dns_rdataset::attributes, isc_region::base, dns_rdataset::covers, dns_rdata::data, dns_name_equal(), dns_name_fromregion(), dns_name_init(), dns_rdata_fromregion(), DNS_RDATA_INIT, dns_rdata_reset(), dns_rdata_tostruct(), dns_rdataset_clone(), dns_rdataset_current(), dns_rdataset_disassociate(), dns_rdataset_first(), dns_rdataset_init(), dns_rdataset_isassociated(), dns_rdataset_next(), DNS_RDATASETATTR_NEGATIVE, dns_trust_none, dns_trust_ultimate, INSIST, isc_buffer_add, isc_buffer_forward, isc_buffer_getuint16(), isc_buffer_getuint8(), isc_buffer_init, isc_buffer_remainingregion, ISC_R_NOMORE, ISC_R_NOTFOUND, ISC_R_SUCCESS, dns_name::length, isc_region::length, dns_rdata::length, dns_rdataset::methods, dns_rdataset::private1, dns_rdataset::private2, dns_rdataset::private3, dns_rdataset::private5, dns_rdataset::private6, dns_rdataset::privateuint4, dns_rdataset::rdclass, REQUIRE, dns_rdataset::trust, dns_rdataset::ttl, and dns_rdataset::type.

Referenced by validate_ncache().

void dns_ncache_current	(	dns_rdataset_t *	ncacherdataset,
		dns_name_t *	found,
		dns_rdataset_t *	rdataset
	)

Extract the current rdataset and name from a ncache entry.

Requires:

• 'ncacherdataset' to be valid and to be a negative cache entry
• 'found' to be valid.
• 'rdataset' to be unassociated.

Definition at line 687 of file ncache.c.

References dns_rdataset::attributes, isc_region::base, dns_rdataset::covers, dns_rdata::data, dns_name_fromregion(), dns_name_init(), dns_rdata_fromregion(), DNS_RDATA_INIT, dns_rdata_reset(), dns_rdata_tostruct(), dns_rdataset_current(), dns_rdataset_isassociated(), DNS_RDATASETATTR_NEGATIVE, dns_trust_ultimate, INSIST, isc_buffer_add, isc_buffer_forward, isc_buffer_getuint16(), isc_buffer_getuint8(), isc_buffer_init, isc_buffer_remainingregion, dns_name::length, isc_region::length, dns_rdata::length, dns_rdataset::methods, dns_rdataset::private1, dns_rdataset::private2, dns_rdataset::private3, dns_rdataset::private5, dns_rdataset::private6, dns_rdataset::privateuint4, dns_rdataset::rdclass, REQUIRE, dns_rdataset::trust, dns_rdataset::ttl, and dns_rdataset::type.

Referenced by isdelegation(), ncache_summary(), query_find(), redirect(), redirect2(), rpz_ck_dnssec(), val_rdataset_first(), val_rdataset_next(), and validate_ncache().

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