/* * query.h -- manipulation with the queries * * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. * * See LICENSE for the license. * */ #ifndef QUERY_H #define QUERY_H #include #include #include "namedb.h" #include "nsd.h" #include "packet.h" #include "tsig.h" struct ixfr_data; enum query_state { QUERY_PROCESSED, QUERY_DISCARDED, QUERY_IN_AXFR, QUERY_IN_IXFR }; typedef enum query_state query_state_type; /* Query as we pass it around */ typedef struct query query_type; struct query { /* * Memory region freed whenever the query is reset. */ region_type *region; /* * The address the query was received from. */ #ifdef INET6 struct sockaddr_storage remote_addr; #else struct sockaddr_in remote_addr; #endif socklen_t remote_addrlen; /* if set, the request came through a proxy */ int is_proxied; /* the client address * the same as remote_addr if not proxied */ #ifdef INET6 struct sockaddr_storage client_addr; #else struct sockaddr_in client_addr; #endif socklen_t client_addrlen; /* * Maximum supported query size. */ size_t maxlen; /* * Space reserved for optional records like EDNS. */ size_t reserved_space; /* EDNS information provided by the client. */ edns_record_type edns; /* TSIG record information and running hash for query-response */ tsig_record_type tsig; /* tsig actions can be overridden, for axfr transfer. */ int tsig_prepare_it, tsig_update_it, tsig_sign_it; int tcp; uint16_t tcplen; buffer_type *packet; /* Normalized query domain name. */ const dname_type *qname; /* Query type and class in host byte order. */ uint16_t qtype; uint16_t qclass; /* The zone used to answer the query. */ zone_type *zone; /* The delegation domain, if any. */ domain_type *delegation_domain; /* The delegation NS rrset, if any. */ rrset_type *delegation_rrset; /* Original opcode. */ uint8_t opcode; /* * The number of CNAMES followed. After a CNAME is followed * we no longer clear AA for a delegation and do not REFUSE * or SERVFAIL if the destination zone of the CNAME does not exist, * or is configured but not present. * Also includes number of DNAMES followed. */ int cname_count; /* Used for dname compression. */ uint16_t compressed_dname_count; domain_type **compressed_dnames; /* * Indexed by domain->number, index 0 is reserved for the * query name when generated from a wildcard record. */ uint16_t *compressed_dname_offsets; size_t compressed_dname_offsets_size; /* number of temporary domains used for the query */ size_t number_temporary_domains; /* * Used for AXFR processing. */ int axfr_is_done; zone_type *axfr_zone; domain_type *axfr_current_domain; rrset_type *axfr_current_rrset; uint16_t axfr_current_rr; /* Used for IXFR processing, * indicates if the zone transfer is done, connection can close. */ int ixfr_is_done; /* the ixfr data that is processed */ struct ixfr_data* ixfr_data; /* the ixfr data that is the last segment */ struct ixfr_data* ixfr_end_data; /* ixfr count of newsoa bytes added, 0 none, len means done */ size_t ixfr_count_newsoa; /* ixfr count of oldsoa bytes added, 0 none, len means done */ size_t ixfr_count_oldsoa; /* ixfr count of del bytes added, 0 none, len means done */ size_t ixfr_count_del; /* ixfr count of add bytes added, 0 none, len means done */ size_t ixfr_count_add; /* position for the end of SOA record, for UDP truncation */ size_t ixfr_pos_of_newsoa; #ifdef RATELIMIT /* if we encountered a wildcard, its domain */ domain_type *wildcard_domain; #endif }; /* Check if the last write resulted in an overflow. */ static inline int query_overflow(struct query *q); /* * Store the offset of the specified domain in the dname compression * table. */ void query_put_dname_offset(struct query *query, domain_type *domain, uint16_t offset); /* * Lookup the offset of the specified domain in the dname compression * table. Offset 0 is used to indicate the domain is not yet in the * compression table. */ static inline uint16_t query_get_dname_offset(struct query *query, domain_type *domain) { return query->compressed_dname_offsets[domain->number]; } /* * Remove all compressed dnames that have an offset that points beyond * the end of the current answer. This must be done after some RRs * are truncated and before adding new RRs. Otherwise dnames may be * compressed using truncated data! */ void query_clear_dname_offsets(struct query *query, size_t max_offset); /* * Clear the compression tables. */ void query_clear_compression_tables(struct query *query); /* * Enter the specified domain into the compression table starting at * the specified offset. */ void query_add_compression_domain(struct query *query, domain_type *domain, uint16_t offset); /* * Create a new query structure. */ query_type *query_create(region_type *region, uint16_t *compressed_dname_offsets, size_t compressed_dname_size, domain_type **compressed_dnames); /* * Reset a query structure so it is ready for receiving and processing * a new query. */ void query_reset(query_type *query, size_t maxlen, int is_tcp); /* * Process a query and write the response in the query I/O buffer. */ query_state_type query_process(query_type *q, nsd_type *nsd, uint32_t *now_p); /* * Prepare the query structure for writing the response. The packet * data up-to the current packet limit is preserved. This usually * includes the packet header and question section. Space is reserved * for the optional EDNS record, if required. */ void query_prepare_response(query_type *q); /* * Add EDNS0 information to the response if required. */ void query_add_optional(query_type *q, nsd_type *nsd, uint32_t *now_p); /* * Write an error response into the query structure with the indicated * RCODE. */ query_state_type query_error(query_type *q, nsd_rc_type rcode); static inline int query_overflow(query_type *q) { return buffer_position(q->packet) > (q->maxlen - q->reserved_space); } #endif /* QUERY_H */