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Diffstat (limited to 'external/unbound/util/data/msgreply.h')
| -rw-r--r-- | external/unbound/util/data/msgreply.h | 438 |
1 files changed, 438 insertions, 0 deletions
diff --git a/external/unbound/util/data/msgreply.h b/external/unbound/util/data/msgreply.h new file mode 100644 index 000000000..ccbd0d748 --- /dev/null +++ b/external/unbound/util/data/msgreply.h @@ -0,0 +1,438 @@ +/* + * util/data/msgreply.h - store message and reply data. + * + * 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 COPYRIGHT + * HOLDER 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 a data structure to store a message and its reply. + */ + +#ifndef UTIL_DATA_MSGREPLY_H +#define UTIL_DATA_MSGREPLY_H +#include "util/storage/lruhash.h" +#include "util/data/packed_rrset.h" +struct sldns_buffer; +struct comm_reply; +struct alloc_cache; +struct iovec; +struct regional; +struct edns_data; +struct msg_parse; +struct rrset_parse; + +/** calculate the prefetch TTL as 90% of original. Calculation + * without numerical overflow (uin32_t) */ +#define PREFETCH_TTL_CALC(ttl) ((ttl) - (ttl)/10) + +/** + * Structure to store query information that makes answers to queries + * different. + */ +struct query_info { + /** + * Salient data on the query: qname, in wireformat. + * can be allocated or a pointer to outside buffer. + * User has to keep track on the status of this. + */ + uint8_t* qname; + /** length of qname (including last 0 octet) */ + size_t qname_len; + /** qtype, host byte order */ + uint16_t qtype; + /** qclass, host byte order */ + uint16_t qclass; +}; + +/** + * Information to reference an rrset + */ +struct rrset_ref { + /** the key with lock, and ptr to packed data. */ + struct ub_packed_rrset_key* key; + /** id needed */ + rrset_id_t id; +}; + +/** + * Structure to store DNS query and the reply packet. + * To use it, copy over the flags from reply and modify using flags from + * the query (RD,CD if not AA). prepend ID. + * + * Memory layout is: + * o struct + * o rrset_ref array + * o packed_rrset_key* array. + * + * Memory layout is sometimes not packed, when the message is synthesized, + * for easy of the generation. It is allocated packed when it is copied + * from the region allocation to the malloc allocation. + */ +struct reply_info { + /** the flags for the answer, host byte order. */ + uint16_t flags; + + /** + * This flag informs unbound the answer is authoritative and + * the AA flag should be preserved. + */ + uint8_t authoritative; + + /** + * Number of RRs in the query section. + * If qdcount is not 0, then it is 1, and the data that appears + * in the reply is the same as the query_info. + * Host byte order. + */ + uint8_t qdcount; + + /** 32 bit padding to pad struct member alignment to 64 bits. */ + uint32_t padding; + + /** + * TTL of the entire reply (for negative caching). + * only for use when there are 0 RRsets in this message. + * if there are RRsets, check those instead. + */ + time_t ttl; + + /** + * TTL for prefetch. After it has expired, a prefetch is suitable. + * Smaller than the TTL, otherwise the prefetch would not happen. + */ + time_t prefetch_ttl; + + /** + * The security status from DNSSEC validation of this message. + */ + enum sec_status security; + + /** + * Number of RRsets in each section. + * The answer section. Add up the RRs in every RRset to calculate + * the number of RRs, and the count for the dns packet. + * The number of RRs in RRsets can change due to RRset updates. + */ + size_t an_numrrsets; + + /** Count of authority section RRsets */ + size_t ns_numrrsets; + /** Count of additional section RRsets */ + size_t ar_numrrsets; + + /** number of RRsets: an_numrrsets + ns_numrrsets + ar_numrrsets */ + size_t rrset_count; + + /** + * List of pointers (only) to the rrsets in the order in which + * they appear in the reply message. + * Number of elements is ancount+nscount+arcount RRsets. + * This is a pointer to that array. + * Use the accessor function for access. + */ + struct ub_packed_rrset_key** rrsets; + + /** + * Packed array of ids (see counts) and pointers to packed_rrset_key. + * The number equals ancount+nscount+arcount RRsets. + * These are sorted in ascending pointer, the locking order. So + * this list can be locked (and id, ttl checked), to see if + * all the data is available and recent enough. + * + * This is defined as an array of size 1, so that the compiler + * associates the identifier with this position in the structure. + * Array bound overflow on this array then gives access to the further + * elements of the array, which are allocated after the main structure. + * + * It could be more pure to define as array of size 0, ref[0]. + * But ref[1] may be less confusing for compilers. + * Use the accessor function for access. + */ + struct rrset_ref ref[1]; +}; + +/** + * Structure to keep hash table entry for message replies. + */ +struct msgreply_entry { + /** the hash table key */ + struct query_info key; + /** the hash table entry, data is struct reply_info* */ + struct lruhash_entry entry; +}; + +/** + * Constructor for replyinfo. + * @param region: where to allocate the results, pass NULL to use malloc. + * @param flags: flags for the replyinfo. + * @param qd: qd count + * @param ttl: TTL of replyinfo + * @param prettl: prefetch ttl + * @param an: an count + * @param ns: ns count + * @param ar: ar count + * @param total: total rrset count (presumably an+ns+ar). + * @param sec: security status of the reply info. + * @return the reply_info base struct with the array for putting the rrsets + * in. The array has been zeroed. Returns NULL on malloc failure. + */ +struct reply_info* +construct_reply_info_base(struct regional* region, uint16_t flags, size_t qd, + time_t ttl, time_t prettl, size_t an, size_t ns, size_t ar, + size_t total, enum sec_status sec); + +/** + * Parse wire query into a queryinfo structure, return 0 on parse error. + * initialises the (prealloced) queryinfo structure as well. + * This query structure contains a pointer back info the buffer! + * This pointer avoids memory allocation. allocqname does memory allocation. + * @param m: the prealloced queryinfo structure to put query into. + * must be unused, or _clear()ed. + * @param query: the wireformat packet query. starts with ID. + * @return: 0 on format error. + */ +int query_info_parse(struct query_info* m, struct sldns_buffer* query); + +/** + * Parse query reply. + * Fills in preallocated query_info structure (with ptr into buffer). + * Allocates reply_info and packed_rrsets. These are not yet added to any + * caches or anything, this is only parsing. Returns formerror on qdcount > 1. + * @param pkt: the packet buffer. Must be positioned after the query section. + * @param alloc: creates packed rrset key structures. + * @param rep: allocated reply_info is returned (only on no error). + * @param qinf: query_info is returned (only on no error). + * @param region: where to store temporary data (for parsing). + * @param edns: where to store edns information, does not need to be inited. + * @return: zero is OK, or DNS error code in case of error + * o FORMERR for parse errors. + * o SERVFAIL for memory allocation errors. + */ +int reply_info_parse(struct sldns_buffer* pkt, struct alloc_cache* alloc, + struct query_info* qinf, struct reply_info** rep, + struct regional* region, struct edns_data* edns); + +/** + * Allocate and decompress parsed message and rrsets. + * @param pkt: for name decompression. + * @param msg: parsed message in scratch region. + * @param alloc: alloc cache for special rrset key structures. + * Not used if region!=NULL, it can be NULL in that case. + * @param qinf: where to store query info. + * qinf itself is allocated by the caller. + * @param rep: reply info is allocated and returned. + * @param region: if this parameter is NULL then malloc and the alloc is used. + * otherwise, everything is allocated in this region. + * In a region, no special rrset key structures are needed (not shared), + * and no rrset_ref array in the reply is built up. + * @return 0 if allocation failed. + */ +int parse_create_msg(struct sldns_buffer* pkt, struct msg_parse* msg, + struct alloc_cache* alloc, struct query_info* qinf, + struct reply_info** rep, struct regional* region); + +/** + * Sorts the ref array. + * @param rep: reply info. rrsets must be filled in. + */ +void reply_info_sortref(struct reply_info* rep); + +/** + * Set TTLs inside the replyinfo to absolute values. + * @param rep: reply info. rrsets must be filled in. + * Also refs must be filled in. + * @param timenow: the current time. + */ +void reply_info_set_ttls(struct reply_info* rep, time_t timenow); + +/** + * Delete reply_info and packed_rrsets (while they are not yet added to the + * hashtables.). Returns rrsets to the alloc cache. + * @param rep: reply_info to delete. + * @param alloc: where to return rrset structures to. + */ +void reply_info_parsedelete(struct reply_info* rep, struct alloc_cache* alloc); + +/** + * Compare two queryinfo structures, on query and type, class. + * It is _not_ sorted in canonical ordering. + * @param m1: struct query_info* , void* here to ease use as function pointer. + * @param m2: struct query_info* , void* here to ease use as function pointer. + * @return: 0 = same, -1 m1 is smaller, +1 m1 is larger. + */ +int query_info_compare(void* m1, void* m2); + +/** clear out query info structure */ +void query_info_clear(struct query_info* m); + +/** calculate size of struct query_info + reply_info */ +size_t msgreply_sizefunc(void* k, void* d); + +/** delete msgreply_entry key structure */ +void query_entry_delete(void *q, void* arg); + +/** delete reply_info data structure */ +void reply_info_delete(void* d, void* arg); + +/** calculate hash value of query_info, lowercases the qname */ +hashvalue_t query_info_hash(struct query_info *q); + +/** + * Setup query info entry + * @param q: query info to copy. Emptied as if clear is called. + * @param r: reply to init data. + * @param h: hash value. + * @return: newly allocated message reply cache item. + */ +struct msgreply_entry* query_info_entrysetup(struct query_info* q, + struct reply_info* r, hashvalue_t h); + +/** + * Copy reply_info and all rrsets in it and allocate. + * @param rep: what to copy, probably inside region, no ref[] array in it. + * @param alloc: how to allocate rrset keys. + * Not used if region!=NULL, it can be NULL in that case. + * @param region: if this parameter is NULL then malloc and the alloc is used. + * otherwise, everything is allocated in this region. + * In a region, no special rrset key structures are needed (not shared), + * and no rrset_ref array in the reply is built up. + * @return new reply info or NULL on memory error. + */ +struct reply_info* reply_info_copy(struct reply_info* rep, + struct alloc_cache* alloc, struct regional* region); + +/** + * Copy a parsed rrset into given key, decompressing and allocating rdata. + * @param pkt: packet for decompression + * @param msg: the parser message (for flags for trust). + * @param pset: the parsed rrset to copy. + * @param region: if NULL - malloc, else data is allocated in this region. + * @param pk: a freshly obtained rrsetkey structure. No dname is set yet, + * will be set on return. + * Note that TTL will still be relative on return. + * @return false on alloc failure. + */ +int parse_copy_decompress_rrset(struct sldns_buffer* pkt, struct msg_parse* msg, + struct rrset_parse *pset, struct regional* region, + struct ub_packed_rrset_key* pk); + +/** + * Find final cname target in reply, the one matching qinfo. Follows CNAMEs. + * @param qinfo: what to start with. + * @param rep: looks in answer section of this message. + * @return: pointer dname, or NULL if not found. + */ +uint8_t* reply_find_final_cname_target(struct query_info* qinfo, + struct reply_info* rep); + +/** + * Check if cname chain in cached reply is still valid. + * @param rep: reply to check. + * @return: true if valid, false if invalid. + */ +int reply_check_cname_chain(struct reply_info* rep); + +/** + * Check security status of all RRs in the message. + * @param rep: reply to check + * @return: true if all RRs are secure. False if not. + * True if there are zero RRs. + */ +int reply_all_rrsets_secure(struct reply_info* rep); + +/** + * Find answer rrset in reply, the one matching qinfo. Follows CNAMEs, so the + * result may have a different owner name. + * @param qinfo: what to look for. + * @param rep: looks in answer section of this message. + * @return: pointer to rrset, or NULL if not found. + */ +struct ub_packed_rrset_key* reply_find_answer_rrset(struct query_info* qinfo, + struct reply_info* rep); + +/** + * Find rrset in reply, inside the answer section. Does not follow CNAMEs. + * @param rep: looks in answer section of this message. + * @param name: what to look for. + * @param namelen: length of name. + * @param type: looks for (host order). + * @param dclass: looks for (host order). + * @return: pointer to rrset, or NULL if not found. + */ +struct ub_packed_rrset_key* reply_find_rrset_section_an(struct reply_info* rep, + uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass); + +/** + * Find rrset in reply, inside the authority section. Does not follow CNAMEs. + * @param rep: looks in authority section of this message. + * @param name: what to look for. + * @param namelen: length of name. + * @param type: looks for (host order). + * @param dclass: looks for (host order). + * @return: pointer to rrset, or NULL if not found. + */ +struct ub_packed_rrset_key* reply_find_rrset_section_ns(struct reply_info* rep, + uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass); + +/** + * Find rrset in reply, inside any section. Does not follow CNAMEs. + * @param rep: looks in answer,authority and additional section of this message. + * @param name: what to look for. + * @param namelen: length of name. + * @param type: looks for (host order). + * @param dclass: looks for (host order). + * @return: pointer to rrset, or NULL if not found. + */ +struct ub_packed_rrset_key* reply_find_rrset(struct reply_info* rep, + uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass); + +/** + * Debug send the query info and reply info to the log in readable form. + * @param str: descriptive string printed with packet content. + * @param qinfo: query section. + * @param rep: rest of message. + */ +void log_dns_msg(const char* str, struct query_info* qinfo, + struct reply_info* rep); + +/** + * Print string with neat domain name, type, class from query info. + * @param v: at what verbosity level to print this. + * @param str: string of message. + * @param qinf: query info structure with name, type and class. + */ +void log_query_info(enum verbosity_value v, const char* str, + struct query_info* qinf); + +#endif /* UTIL_DATA_MSGREPLY_H */ |