1 /* 2 * util/edns.h - handle base EDNS options. 3 * 4 * Copyright (c) 2018, 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 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains functions for base EDNS options. 40 */ 41 42 #ifndef UTIL_EDNS_H 43 #define UTIL_EDNS_H 44 45 #include "util/storage/dnstree.h" 46 47 struct edns_data; 48 struct config_file; 49 struct comm_point; 50 struct regional; 51 52 /** 53 * Structure containing all EDNS strings. 54 */ 55 struct edns_strings { 56 /** Tree of EDNS client strings to use in upstream queries, per address 57 * prefix. Contains nodes of type edns_string_addr. */ 58 rbtree_type client_strings; 59 /** EDNS opcode to use for client strings */ 60 uint16_t client_string_opcode; 61 /** region to allocate tree nodes in */ 62 struct regional* region; 63 }; 64 65 /** 66 * EDNS string. Node of rbtree, containing string and prefix. 67 */ 68 struct edns_string_addr { 69 /** node in address tree, used for tree lookups. Need to be the first 70 * member of this struct. */ 71 struct addr_tree_node node; 72 /** string, ascii format */ 73 uint8_t* string; 74 /** length of string */ 75 size_t string_len; 76 }; 77 78 /** 79 * Create structure to hold EDNS strings 80 * @return: newly created edns_strings, NULL on alloc failure. 81 */ 82 struct edns_strings* edns_strings_create(void); 83 84 /** Delete EDNS strings structure 85 * @param edns_strings: struct to delete 86 */ 87 void edns_strings_delete(struct edns_strings* edns_strings); 88 89 /** 90 * Add configured EDNS strings 91 * @param edns_strings: edns strings to apply config to 92 * @param config: struct containing EDNS strings configuration 93 * @return 0 on error 94 */ 95 int edns_strings_apply_cfg(struct edns_strings* edns_strings, 96 struct config_file* config); 97 98 /** 99 * Find string for address. 100 * @param tree: tree containing EDNS strings per address prefix. 101 * @param addr: address to use for tree lookup 102 * @param addrlen: length of address 103 * @return: matching tree node, NULL otherwise 104 */ 105 struct edns_string_addr* 106 edns_string_addr_lookup(rbtree_type* tree, struct sockaddr_storage* addr, 107 socklen_t addrlen); 108 109 #endif 110