1 /* $NetBSD: validator.h,v 1.7 2022/09/23 12:15:30 christos Exp $ */ 2 3 /* 4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 5 * 6 * SPDX-License-Identifier: MPL-2.0 7 * 8 * This Source Code Form is subject to the terms of the Mozilla Public 9 * License, v. 2.0. If a copy of the MPL was not distributed with this 10 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 11 * 12 * See the COPYRIGHT file distributed with this work for additional 13 * information regarding copyright ownership. 14 */ 15 16 #ifndef DNS_VALIDATOR_H 17 #define DNS_VALIDATOR_H 1 18 19 /***** 20 ***** Module Info 21 *****/ 22 23 /*! \file dns/validator.h 24 * 25 * \brief 26 * DNS Validator 27 * This is the BIND 9 validator, the module responsible for validating the 28 * rdatasets and negative responses (messages). It makes use of zones in 29 * the view and may fetch RRset to complete trust chains. It implements 30 * DNSSEC as specified in RFC 4033, 4034 and 4035. 31 * 32 * Correct operation is critical to preventing spoofed answers from secure 33 * zones being accepted. 34 * 35 * MP: 36 *\li The module ensures appropriate synchronization of data structures it 37 * creates and manipulates. 38 * 39 * Reliability: 40 *\li No anticipated impact. 41 * 42 * Resources: 43 *\li TBS 44 * 45 * Security: 46 *\li No anticipated impact. 47 * 48 * Standards: 49 *\li RFCs: 1034, 1035, 2181, 4033, 4034, 4035. 50 */ 51 52 #include <stdbool.h> 53 54 #include <isc/event.h> 55 #include <isc/lang.h> 56 #include <isc/mutex.h> 57 58 #include <dns/fixedname.h> 59 #include <dns/rdataset.h> 60 #include <dns/rdatastruct.h> /* for dns_rdata_rrsig_t */ 61 #include <dns/types.h> 62 63 #include <dst/dst.h> 64 65 /*% 66 * A dns_validatorevent_t is sent when a 'validation' completes. 67 * \brief 68 * 'name', 'rdataset', 'sigrdataset', and 'message' are the values that were 69 * supplied when dns_validator_create() was called. They are returned to the 70 * caller so that they may be freed. 71 * 72 * If the RESULT is ISC_R_SUCCESS and the answer is secure then 73 * proofs[] will contain the names of the NSEC records that hold the 74 * various proofs. Note the same name may appear multiple times. 75 */ 76 typedef struct dns_validatorevent { 77 ISC_EVENT_COMMON(struct dns_validatorevent); 78 dns_validator_t *validator; 79 isc_result_t result; 80 /* 81 * Name and type of the response to be validated. 82 */ 83 dns_name_t *name; 84 dns_rdatatype_t type; 85 /* 86 * Rdata and RRSIG (if any) for positive responses. 87 */ 88 dns_rdataset_t *rdataset; 89 dns_rdataset_t *sigrdataset; 90 /* 91 * The full response. Required for negative responses. 92 * Also required for positive wildcard responses. 93 */ 94 dns_message_t *message; 95 /* 96 * Proofs to be cached. 97 */ 98 dns_name_t *proofs[4]; 99 /* 100 * Optout proof seen. 101 */ 102 bool optout; 103 /* 104 * Answer is secure. 105 */ 106 bool secure; 107 } dns_validatorevent_t; 108 109 #define DNS_VALIDATOR_NOQNAMEPROOF 0 110 #define DNS_VALIDATOR_NODATAPROOF 1 111 #define DNS_VALIDATOR_NOWILDCARDPROOF 2 112 #define DNS_VALIDATOR_CLOSESTENCLOSER 3 113 114 /*% 115 * A validator object represents a validation in progress. 116 * \brief 117 * Clients are strongly discouraged from using this type directly, with 118 * the exception of the 'link' field, which may be used directly for 119 * whatever purpose the client desires. 120 */ 121 struct dns_validator { 122 /* Unlocked. */ 123 unsigned int magic; 124 isc_mutex_t lock; 125 dns_view_t *view; 126 /* Locked by lock. */ 127 unsigned int options; 128 unsigned int attributes; 129 dns_validatorevent_t *event; 130 dns_fetch_t *fetch; 131 dns_validator_t *subvalidator; 132 dns_validator_t *parent; 133 dns_keytable_t *keytable; 134 dst_key_t *key; 135 dns_rdata_rrsig_t *siginfo; 136 isc_task_t *task; 137 isc_taskaction_t action; 138 void *arg; 139 unsigned int labels; 140 dns_rdataset_t *currentset; 141 dns_rdataset_t *keyset; 142 dns_rdataset_t *dsset; 143 dns_rdataset_t fdsset; 144 dns_rdataset_t frdataset; 145 dns_rdataset_t fsigrdataset; 146 dns_fixedname_t fname; 147 dns_fixedname_t wild; 148 dns_fixedname_t closest; 149 ISC_LINK(dns_validator_t) link; 150 bool mustbesecure; 151 unsigned int depth; 152 unsigned int authcount; 153 unsigned int authfail; 154 isc_stdtime_t start; 155 }; 156 157 /*% 158 * dns_validator_create() options. 159 */ 160 /* obsolete: #define DNS_VALIDATOR_DLV 0x0001U */ 161 #define DNS_VALIDATOR_DEFER 0x0002U 162 #define DNS_VALIDATOR_NOCDFLAG 0x0004U 163 #define DNS_VALIDATOR_NONTA 0x0008U /*% Ignore NTA table */ 164 165 ISC_LANG_BEGINDECLS 166 167 isc_result_t 168 dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type, 169 dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset, 170 dns_message_t *message, unsigned int options, 171 isc_task_t *task, isc_taskaction_t action, void *arg, 172 dns_validator_t **validatorp); 173 /*%< 174 * Start a DNSSEC validation. 175 * 176 * This validates a response to the question given by 177 * 'name' and 'type'. 178 * 179 * To validate a positive response, the response data is 180 * given by 'rdataset' and 'sigrdataset'. If 'sigrdataset' 181 * is NULL, the data is presumed insecure and an attempt 182 * is made to prove its insecurity by finding the appropriate 183 * null key. 184 * 185 * The complete response message may be given in 'message', 186 * to make available any authority section NSECs that may be 187 * needed for validation of a response resulting from a 188 * wildcard expansion (though no such wildcard validation 189 * is implemented yet). If the complete response message 190 * is not available, 'message' is NULL. 191 * 192 * To validate a negative response, the complete negative response 193 * message is given in 'message'. The 'rdataset', and 194 * 'sigrdataset' arguments must be NULL, but the 'name' and 'type' 195 * arguments must be provided. 196 * 197 * The validation is performed in the context of 'view'. 198 * 199 * When the validation finishes, a dns_validatorevent_t with 200 * the given 'action' and 'arg' are sent to 'task'. 201 * Its 'result' field will be ISC_R_SUCCESS iff the 202 * response was successfully proven to be either secure or 203 * part of a known insecure domain. 204 */ 205 206 void 207 dns_validator_send(dns_validator_t *validator); 208 /*%< 209 * Send a deferred validation request 210 * 211 * Requires: 212 * 'validator' to points to a valid DNSSEC validator. 213 */ 214 215 void 216 dns_validator_cancel(dns_validator_t *validator); 217 /*%< 218 * Cancel a DNSSEC validation in progress. 219 * 220 * Requires: 221 *\li 'validator' points to a valid DNSSEC validator, which 222 * may or may not already have completed. 223 * 224 * Ensures: 225 *\li It the validator has not already sent its completion 226 * event, it will send it with result code ISC_R_CANCELED. 227 */ 228 229 void 230 dns_validator_destroy(dns_validator_t **validatorp); 231 /*%< 232 * Destroy a DNSSEC validator. 233 * 234 * Requires: 235 *\li '*validatorp' points to a valid DNSSEC validator. 236 * \li The validator must have completed and sent its completion 237 * event. 238 * 239 * Ensures: 240 *\li All resources used by the validator are freed. 241 */ 242 243 ISC_LANG_ENDDECLS 244 245 #endif /* DNS_VALIDATOR_H */ 246