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Diffstat (limited to 'services/cache/infra.h')
| -rw-r--r-- | services/cache/infra.h | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/services/cache/infra.h b/services/cache/infra.h new file mode 100644 index 000000000000..161f5ab4319e --- /dev/null +++ b/services/cache/infra.h @@ -0,0 +1,309 @@ +/* + * services/cache/infra.h - infrastructure cache, server rtt and capabilities + * + * Copyright (c) 2007, NLnet Labs. All rights reserved. + * + * This software is open source. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * Neither the name of the NLNET LABS nor the names of its contributors may + * be used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +/** + * \file + * + * This file contains the infrastructure cache. + */ + +#ifndef SERVICES_CACHE_INFRA_H +#define SERVICES_CACHE_INFRA_H +#include "util/storage/lruhash.h" +#include "util/rtt.h" +struct slabhash; +struct config_file; + +/** + * Host information kept for every server, per zone. + */ +struct infra_key { + /** the host address. */ + struct sockaddr_storage addr; + /** length of addr. */ + socklen_t addrlen; + /** zone name in wireformat */ + uint8_t* zonename; + /** length of zonename */ + size_t namelen; + /** hash table entry, data of type infra_data. */ + struct lruhash_entry entry; +}; + +/** + * Host information encompasses host capabilities and retransmission timeouts. + * And lameness information (notAuthoritative, noEDNS, Recursive) + */ +struct infra_data { + /** TTL value for this entry. absolute time. */ + uint32_t ttl; + + /** time in seconds (absolute) when probing re-commences, 0 disabled */ + uint32_t probedelay; + /** round trip times for timeout calculation */ + struct rtt_info rtt; + + /** edns version that the host supports, -1 means no EDNS */ + int edns_version; + /** if the EDNS lameness is already known or not. + * EDNS lame is when EDNS queries or replies are dropped, + * and cause a timeout */ + uint8_t edns_lame_known; + + /** is the host lame (does not serve the zone authoritatively), + * or is the host dnssec lame (does not serve DNSSEC data) */ + uint8_t isdnsseclame; + /** is the host recursion lame (not AA, but RA) */ + uint8_t rec_lame; + /** the host is lame (not authoritative) for A records */ + uint8_t lame_type_A; + /** the host is lame (not authoritative) for other query types */ + uint8_t lame_other; + + /** timeouts counter for type A */ + uint8_t timeout_A; + /** timeouts counter for type AAAA */ + uint8_t timeout_AAAA; + /** timeouts counter for others */ + uint8_t timeout_other; +}; + +/** + * Infra cache + */ +struct infra_cache { + /** The hash table with hosts */ + struct slabhash* hosts; + /** TTL value for host information, in seconds */ + int host_ttl; +}; + +/** infra host cache default hash lookup size */ +#define INFRA_HOST_STARTSIZE 32 +/** bytes per zonename reserved in the hostcache, dnamelen(zonename.com.) */ +#define INFRA_BYTES_NAME 14 + +/** + * Create infra cache. + * @param cfg: config parameters or NULL for defaults. + * @return: new infra cache, or NULL. + */ +struct infra_cache* infra_create(struct config_file* cfg); + +/** + * Delete infra cache. + * @param infra: infrastructure cache to delete. + */ +void infra_delete(struct infra_cache* infra); + +/** + * Adjust infra cache to use updated configuration settings. + * This may clean the cache. Operates a bit like realloc. + * There may be no threading or use by other threads. + * @param infra: existing cache. If NULL a new infra cache is returned. + * @param cfg: config options. + * @return the new infra cache pointer or NULL on error. + */ +struct infra_cache* infra_adjust(struct infra_cache* infra, + struct config_file* cfg); + +/** + * Plain find infra data function (used by the the other functions) + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: domain name of zone. + * @param namelen: length of domain name. + * @param wr: if true, writelock, else readlock. + * @return the entry, could be expired (this is not checked) or NULL. + */ +struct lruhash_entry* infra_lookup_nottl(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* name, + size_t namelen, int wr); + +/** + * Find host information to send a packet. Creates new entry if not found. + * Lameness is empty. EDNS is 0 (try with first), and rtt is returned for + * the first message to it. + * Use this to send a packet only, because it also locks out others when + * probing is restricted. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: domain name of zone. + * @param namelen: length of domain name. + * @param timenow: what time it is now. + * @param edns_vs: edns version it supports, is returned. + * @param edns_lame_known: if EDNS lame (EDNS is dropped in transit) has + * already been probed, is returned. + * @param to: timeout to use, is returned. + * @return: 0 on error. + */ +int infra_host(struct infra_cache* infra, struct sockaddr_storage* addr, + socklen_t addrlen, uint8_t* name, size_t namelen, + uint32_t timenow, int* edns_vs, uint8_t* edns_lame_known, int* to); + +/** + * Set a host to be lame for the given zone. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: domain name of zone apex. + * @param namelen: length of domain name. + * @param timenow: what time it is now. + * @param dnsseclame: if true the host is set dnssec lame. + * if false, the host is marked lame (not serving the zone). + * @param reclame: if true host is a recursor not AA server. + * if false, dnsseclame or marked lame. + * @param qtype: the query type for which it is lame. + * @return: 0 on error. + */ +int infra_set_lame(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, + uint8_t* name, size_t namelen, uint32_t timenow, int dnsseclame, + int reclame, uint16_t qtype); + +/** + * Update rtt information for the host. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: zone name + * @param namelen: zone name length + * @param qtype: query type. + * @param roundtrip: estimate of roundtrip time in milliseconds or -1 for + * timeout. + * @param orig_rtt: original rtt for the query that timed out (roundtrip==-1). + * ignored if roundtrip != -1. + * @param timenow: what time it is now. + * @return: 0 on error. new rto otherwise. + */ +int infra_rtt_update(struct infra_cache* infra, struct sockaddr_storage* addr, + socklen_t addrlen, uint8_t* name, size_t namelen, int qtype, + int roundtrip, int orig_rtt, uint32_t timenow); + +/** + * Update information for the host, store that a TCP transaction works. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: name of zone + * @param namelen: length of name + */ +void infra_update_tcp_works(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, + uint8_t* name, size_t namelen); + +/** + * Update edns information for the host. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: name of zone + * @param namelen: length of name + * @param edns_version: the version that it publishes. + * If it is known to support EDNS then no-EDNS is not stored over it. + * @param timenow: what time it is now. + * @return: 0 on error. + */ +int infra_edns_update(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, + uint8_t* name, size_t namelen, int edns_version, uint32_t timenow); + +/** + * Get Lameness information and average RTT if host is in the cache. + * This information is to be used for server selection. + * @param infra: infrastructure cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: zone name. + * @param namelen: zone name length. + * @param qtype: the query to be made. + * @param lame: if function returns true, this returns lameness of the zone. + * @param dnsseclame: if function returns true, this returns if the zone + * is dnssec-lame. + * @param reclame: if function returns true, this is if it is recursion lame. + * @param rtt: if function returns true, this returns avg rtt of the server. + * The rtt value is unclamped and reflects recent timeouts. + * @param timenow: what time it is now. + * @return if found in cache, or false if not (or TTL bad). + */ +int infra_get_lame_rtt(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, + uint8_t* name, size_t namelen, uint16_t qtype, + int* lame, int* dnsseclame, int* reclame, int* rtt, uint32_t timenow); + +/** + * Get additional (debug) info on timing. + * @param infra: infra cache. + * @param addr: host address. + * @param addrlen: length of addr. + * @param name: zone name + * @param namelen: zone name length + * @param rtt: the rtt_info is copied into here (caller alloced return struct). + * @param delay: probe delay (if any). + * @param timenow: what time it is now. + * @param tA: timeout counter on type A. + * @param tAAAA: timeout counter on type AAAA. + * @param tother: timeout counter on type other. + * @return TTL the infra host element is valid for. If -1: not found in cache. + * TTL -2: found but expired. + */ +int infra_get_host_rto(struct infra_cache* infra, + struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* name, + size_t namelen, struct rtt_info* rtt, int* delay, uint32_t timenow, + int* tA, int* tAAAA, int* tother); + +/** + * Get memory used by the infra cache. + * @param infra: infrastructure cache. + * @return memory in use in bytes. + */ +size_t infra_get_mem(struct infra_cache* infra); + +/** calculate size for the hashtable, does not count size of lameness, + * so the hashtable is a fixed number of items */ +size_t infra_sizefunc(void* k, void* d); + +/** compare two addresses, returns -1, 0, or +1 */ +int infra_compfunc(void* key1, void* key2); + +/** delete key, and destroy the lock */ +void infra_delkeyfunc(void* k, void* arg); + +/** delete data and destroy the lameness hashtable */ +void infra_deldatafunc(void* d, void* arg); + +#endif /* SERVICES_CACHE_INFRA_H */ |