msgencode.h revision 269257
1116742Ssam/* 2116904Ssam * util/data/msgencode.h - encode compressed DNS messages. 3178354Ssam * 4116742Ssam * Copyright (c) 2007, NLnet Labs. All rights reserved. 5116742Ssam * 6116742Ssam * This software is open source. 7116742Ssam * 8116742Ssam * Redistribution and use in source and binary forms, with or without 9116742Ssam * modification, are permitted provided that the following conditions 10116904Ssam * are met: 11116904Ssam * 12116904Ssam * Redistributions of source code must retain the above copyright notice, 13116904Ssam * this list of conditions and the following disclaimer. 14116742Ssam * 15116904Ssam * Redistributions in binary form must reproduce the above copyright notice, 16116904Ssam * this list of conditions and the following disclaimer in the documentation 17116904Ssam * and/or other materials provided with the distribution. 18116904Ssam * 19116904Ssam * Neither the name of the NLNET LABS nor the names of its contributors may 20116904Ssam * be used to endorse or promote products derived from this software without 21116904Ssam * specific prior written permission. 22116904Ssam * 23116904Ssam * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24116904Ssam * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25116742Ssam * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26116742Ssam * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27116742Ssam * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28116742Ssam * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29116742Ssam * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30116742Ssam * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31116742Ssam * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32116742Ssam * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33116742Ssam * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34116742Ssam */ 35178354Ssam 36116742Ssam/** 37116742Ssam * \file 38138568Ssam * 39170530Ssam * This file contains temporary data structures and routines to create 40170530Ssam * compressed DNS messages. 41116742Ssam */ 42178354Ssam 43116742Ssam#ifndef UTIL_DATA_MSGENCODE_H 44116742Ssam#define UTIL_DATA_MSGENCODE_H 45116742Ssamstruct sldns_buffer; 46138568Ssamstruct query_info; 47116742Ssamstruct reply_info; 48116742Ssamstruct regional; 49178354Ssamstruct edns_data; 50178354Ssam 51178354Ssam/** 52178354Ssam * Generate answer from reply_info. 53195618Srpaulo * @param qinf: query information that provides query section in packet. 54195618Srpaulo * @param rep: reply to fill in. 55195618Srpaulo * @param id: id word from the query. 56178354Ssam * @param qflags: flags word from the query. 57178354Ssam * @param dest: buffer to put message into; will truncate if it does not fit. 58116742Ssam * @param timenow: time to subtract. 59138568Ssam * @param cached: set true if a cached reply (so no AA bit). 60138568Ssam * set false for the first reply. 61138568Ssam * @param region: where to allocate temp variables (for compression). 62116742Ssam * @param udpsize: size of the answer, 512, from EDNS, or 64k for TCP. 63116742Ssam * @param edns: EDNS data included in the answer, NULL for none. 64116742Ssam * or if edns_present = 0, it is not included. 65116742Ssam * @param dnssec: if 0 DNSSEC records are omitted from the answer. 66116742Ssam * @param secure: if 1, the AD bit is set in the reply. 67218927Sbschmidt * @return: 0 on error (server failure). 68116742Ssam */ 69138568Ssamint reply_info_answer_encode(struct query_info* qinf, struct reply_info* rep, 70138568Ssam uint16_t id, uint16_t qflags, struct sldns_buffer* dest, time_t timenow, 71138568Ssam int cached, struct regional* region, uint16_t udpsize, 72138568Ssam struct edns_data* edns, int dnssec, int secure); 73138568Ssam 74138568Ssam/** 75167283Ssam * Regenerate the wireformat from the stored msg reply. 76167283Ssam * If the buffer is too small then the message is truncated at a whole 77167283Ssam * rrset and the TC bit set, or whole rrsets are left out of the additional 78178354Ssam * and the TC bit is not set. 79167283Ssam * @param qinfo: query info to store. 80167283Ssam * @param rep: reply to store. 81195618Srpaulo * @param id: id value to store, network order. 82195618Srpaulo * @param flags: flags value to store, host order. 83167283Ssam * @param buffer: buffer to store the packet into. 84117811Ssam * @param timenow: time now, to adjust ttl values. 85117811Ssam * @param region: to store temporary data in. 86117811Ssam * @param udpsize: size of the answer, 512, from EDNS, or 64k for TCP. 87117811Ssam * @param dnssec: if 0 DNSSEC records are omitted from the answer. 88117811Ssam * @return: nonzero is success, or 89172058Ssam * 0 on error: malloc failure (no log_err has been done). 90172058Ssam */ 91172058Ssamint reply_info_encode(struct query_info* qinfo, struct reply_info* rep, 92172058Ssam uint16_t id, uint16_t flags, struct sldns_buffer* buffer, time_t timenow, 93117811Ssam struct regional* region, uint16_t udpsize, int dnssec); 94138568Ssam 95138568Ssam/** 96138568Ssam * Encode query packet. Assumes the buffer is large enough. 97138568Ssam * @param pkt: where to store the packet. 98138568Ssam * @param qinfo: query info. 99138568Ssam */ 100138568Ssamvoid qinfo_query_encode(struct sldns_buffer* pkt, struct query_info* qinfo); 101116742Ssam 102191746Sthompsa/** 103191746Sthompsa * Estimate size of EDNS record in packet. EDNS record will be no larger. 104178354Ssam * @param edns: edns data or NULL. 105191746Sthompsa * @return octets to reserve for EDNS. 106191746Sthompsa */ 107191746Sthompsauint16_t calc_edns_field_size(struct edns_data* edns); 108233452Sadrian 109191746Sthompsa/** 110117811Ssam * Attach EDNS record to buffer. Buffer has complete packet. There must 111178354Ssam * be enough room left for the EDNS record. 112178354Ssam * @param pkt: packet added to. 113178354Ssam * @param edns: if NULL or present=0, nothing is added to the packet. 114172211Ssam */ 115178354Ssamvoid attach_edns_record(struct sldns_buffer* pkt, struct edns_data* edns); 116178354Ssam 117178354Ssam/** 118178354Ssam * Encode an error. With QR and RA set. 119178354Ssam * 120172211Ssam * @param pkt: where to store the packet. 121172211Ssam * @param r: RCODE value to encode. 122116742Ssam * @param qinfo: if not NULL, the query is included. 123138568Ssam * @param qid: query ID to set in packet. network order. 124116742Ssam * @param qflags: original query flags (to copy RD and CD bits). host order. 125138568Ssam * @param edns: if not NULL, this is the query edns info, 126116742Ssam * and an edns reply is attached. Only attached if EDNS record fits reply. 127178354Ssam */ 128178354Ssamvoid error_encode(struct sldns_buffer* pkt, int r, struct query_info* qinfo, 129178354Ssam uint16_t qid, uint16_t qflags, struct edns_data* edns); 130178354Ssam 131178354Ssam#endif /* UTIL_DATA_MSGENCODE_H */ 132178354Ssam