1 /* 2 * libunbound/worker.h - worker thread or process that resolves 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 27 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 * POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains the worker process or thread that performs 40 * the DNS resolving and validation. The worker is called by a procedure 41 * and if in the background continues until exit, if in the foreground 42 * returns from the procedure when done. 43 */ 44 #ifndef LIBUNBOUND_LIBWORKER_H 45 #define LIBUNBOUND_LIBWORKER_H 46 #include "util/data/packed_rrset.h" 47 struct ub_ctx; 48 struct ub_result; 49 struct module_env; 50 struct comm_base; 51 struct outside_network; 52 struct ub_randstate; 53 struct ctx_query; 54 struct outbound_entry; 55 struct module_qstate; 56 struct comm_point; 57 struct comm_reply; 58 struct regional; 59 struct tube; 60 61 /** 62 * The library-worker status structure 63 * Internal to the worker. 64 */ 65 struct libworker { 66 /** every worker has a unique thread_num. (first in struct) */ 67 int thread_num; 68 /** context we are operating under */ 69 struct ub_ctx* ctx; 70 71 /** is this the bg worker? */ 72 int is_bg; 73 /** is this a bg worker that is threaded (not forked)? */ 74 int is_bg_thread; 75 76 /** copy of the module environment with worker local entries. */ 77 struct module_env* env; 78 /** the event base this worker works with */ 79 struct comm_base* base; 80 /** the backside outside network interface to the auth servers */ 81 struct outside_network* back; 82 /** random() table for this worker. */ 83 struct ub_randstate* rndstate; 84 /** sslcontext for SSL wrapped DNS over TCP queries */ 85 void* sslctx; 86 }; 87 88 /** 89 * Create a background worker 90 * @param ctx: is updated with pid/tid of the background worker. 91 * a new allocation cache is obtained from ctx. It contains the 92 * threadnumber and unique id for further (shared) cache insertions. 93 * @return 0 if OK, else error. 94 * Further communication is done via the pipes in ctx. 95 */ 96 int libworker_bg(struct ub_ctx* ctx); 97 98 /** 99 * Create a foreground worker. 100 * This worker will join the threadpool of resolver threads. 101 * It exits when the query answer has been obtained (or error). 102 * This routine blocks until the worker is finished. 103 * @param ctx: new allocation cache obtained and returned to it. 104 * @param q: query (result is stored in here). 105 * @return 0 if finished OK, else error. 106 */ 107 int libworker_fg(struct ub_ctx* ctx, struct ctx_query* q); 108 109 /** cleanup the cache to remove all rrset IDs from it, arg is libworker */ 110 void libworker_alloc_cleanup(void* arg); 111 112 /** 113 * fill result from parsed message, on error fills servfail 114 * @param res: is clear at start, filled in at end. 115 * @param buf: contains DNS message. 116 * @param temp: temporary buffer for parse. 117 * @param msg_security: security status of the DNS message. 118 * On error, the res may contain a different status 119 * (out of memory is not secure, not bogus). 120 */ 121 void libworker_enter_result(struct ub_result* res, ldns_buffer* buf, 122 struct regional* temp, enum sec_status msg_security); 123 124 #endif /* LIBUNBOUND_LIBWORKER_H */ 125