/* * 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 */