/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#ifndef DNS_BADCACHE_H
#define DNS_BADCACHE_H 1
/*****
***** Module Info
*****/
/*! \file dns/badcache.h
* \brief
* Defines dns_badcache_t, the "bad cache" object.
*
* Notes:
*\li A bad cache object is a hash table of name/type tuples,
* indicating whether a given tuple known to be "bad" in some
* sense (e.g., queries for that name and type have been
* returning SERVFAIL). This is used for both the "bad server
* cache" in the resolver and for the "servfail cache" in
* the view.
*
* Reliability:
*
* Resources:
*
* Security:
*
* Standards:
*/
/***
*** Imports
***/
#include <inttypes.h>
#include <stdbool.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
/***
*** Functions
***/
isc_result_t
dns_badcache_init(isc_mem_t *mctx, unsigned int size, dns_badcache_t **bcp);
/*%
* Allocate and initialize a badcache and store it in '*bcp'.
*
* Requires:
* \li mctx != NULL
* \li bcp != NULL
* \li *bcp == NULL
*/
void
dns_badcache_destroy(dns_badcache_t **bcp);
/*%
* Flush and then free badcache in 'bcp'. '*bcp' is set to NULL on return.
*
* Requires:
* \li '*bcp' to be a valid badcache
*/
void
dns_badcache_add(dns_badcache_t *bc, const dns_name_t *name,
dns_rdatatype_t type, bool update, uint32_t flags,
isc_time_t *expire);
/*%
* Adds a badcache entry to the badcache 'bc' for name 'name' and
* type 'type'. If an entry already exists, then it will be updated if
* 'update' is true. The entry will be stored with flags 'flags'
* and expiration date 'expire'.
*
* Requires:
* \li bc to be a valid badcache.
* \li name != NULL
* \li expire != NULL
*/
bool
dns_badcache_find(dns_badcache_t *bc, const dns_name_t *name,
dns_rdatatype_t type, uint32_t *flagp, isc_time_t *now);
/*%
* Returns true if a record is found in the badcache 'bc' matching
* 'name' and 'type', with an expiration date later than 'now'.
* If 'flagp' is not NULL, then '*flagp' is updated to the flags
* that were stored in the badcache entry. Returns false if
* no matching record is found.
*
* Requires:
* \li bc to be a valid badcache.
* \li name != NULL
* \li now != NULL
*/
void
dns_badcache_flush(dns_badcache_t *bc);
/*%
* Flush the entire bad cache.
*
* Requires:
* \li bc to be a valid badcache
*/
void
dns_badcache_flushname(dns_badcache_t *bc, const dns_name_t *name);
/*%
* Flush the bad cache of all entries at 'name'.
*
* Requires:
* \li bc to be a valid badcache
* \li name != NULL
*/
void
dns_badcache_flushtree(dns_badcache_t *bc, const dns_name_t *name);
/*%
* Flush the bad cache of all entries at or below 'name'.
*
* Requires:
* \li bc to be a valid badcache
* \li name != NULL
*/
void
dns_badcache_print(dns_badcache_t *bc, const char *cachename, FILE *fp);
/*%
* Print the contents of badcache 'bc' (headed by the title 'cachename')
* to file pointer 'fp'.
*
* Requires:
* \li bc to be a valid badcache
* \li cachename != NULL
* \li fp != NULL
*/
ISC_LANG_ENDDECLS
#endif /* DNS_BADCACHE_H */
