1 /* $NetBSD: acl.h,v 1.10 2025/01/26 16:25:26 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 #pragma once 17 18 /***** 19 ***** Module Info 20 *****/ 21 22 /*! \file dns/acl.h 23 * \brief 24 * Address match list handling. 25 */ 26 27 /* Add -DDNS_ACL_TRACE=1 to CFLAGS for detailed reference tracing */ 28 29 /*** 30 *** Imports 31 ***/ 32 33 #include <stdbool.h> 34 35 #include <isc/lang.h> 36 #include <isc/magic.h> 37 #include <isc/netaddr.h> 38 #include <isc/refcount.h> 39 40 #include <dns/geoip.h> 41 #include <dns/iptable.h> 42 #include <dns/name.h> 43 #include <dns/types.h> 44 45 /*** 46 *** Types 47 ***/ 48 49 typedef enum { 50 dns_aclelementtype_keyname, 51 dns_aclelementtype_nestedacl, 52 dns_aclelementtype_localhost, 53 dns_aclelementtype_localnets, 54 #if defined(HAVE_GEOIP2) 55 dns_aclelementtype_geoip 56 #endif /* HAVE_GEOIP2 */ 57 } dns_aclelementtype_t; 58 59 typedef struct dns_acl_port_transports { 60 in_port_t port; 61 uint32_t transports; 62 bool encrypted; /* for protocols with optional encryption (e.g. HTTP) */ 63 bool negative; 64 ISC_LINK(struct dns_acl_port_transports) link; 65 } dns_acl_port_transports_t; 66 67 typedef struct dns_aclipprefix dns_aclipprefix_t; 68 69 struct dns_aclipprefix { 70 isc_netaddr_t address; /* IP4/IP6 */ 71 unsigned int prefixlen; 72 }; 73 74 struct dns_aclelement { 75 dns_aclelementtype_t type; 76 bool negative; 77 dns_name_t keyname; 78 #if defined(HAVE_GEOIP2) 79 dns_geoip_elem_t geoip_elem; 80 #endif /* HAVE_GEOIP2 */ 81 dns_acl_t *nestedacl; 82 int node_num; 83 }; 84 85 #define dns_acl_node_count(acl) acl->iptable->radix->num_added_node 86 87 struct dns_acl { 88 unsigned int magic; 89 isc_mem_t *mctx; 90 isc_refcount_t references; 91 dns_iptable_t *iptable; 92 dns_aclelement_t *elements; 93 bool has_negatives; 94 unsigned int alloc; /*%< Elements allocated */ 95 unsigned int length; /*%< Elements initialized */ 96 char *name; /*%< Temporary use only */ 97 ISC_LINK(dns_acl_t) nextincache; /*%< Ditto */ 98 ISC_LIST(dns_acl_port_transports_t) ports_and_transports; 99 size_t port_proto_entries; 100 }; 101 102 struct dns_aclenv { 103 unsigned int magic; 104 isc_mem_t *mctx; 105 isc_refcount_t references; 106 107 dns_acl_t *localhost; 108 dns_acl_t *localnets; 109 110 bool match_mapped; 111 #if defined(HAVE_GEOIP2) 112 dns_geoip_databases_t *geoip; 113 #endif /* HAVE_GEOIP2 */ 114 }; 115 116 #define DNS_ACL_MAGIC ISC_MAGIC('D', 'a', 'c', 'l') 117 #define DNS_ACL_VALID(a) ISC_MAGIC_VALID(a, DNS_ACL_MAGIC) 118 119 /*** 120 *** Functions 121 ***/ 122 123 ISC_LANG_BEGINDECLS 124 125 void 126 dns_acl_create(isc_mem_t *mctx, int n, dns_acl_t **target); 127 /*%< 128 * Create a new ACL, including an IP table and an array with room 129 * for 'n' ACL elements. The elements are uninitialized and the 130 * length is 0. 131 */ 132 133 isc_result_t 134 dns_acl_any(isc_mem_t *mctx, dns_acl_t **target); 135 /*%< 136 * Create a new ACL that matches everything. 137 */ 138 139 isc_result_t 140 dns_acl_none(isc_mem_t *mctx, dns_acl_t **target); 141 /*%< 142 * Create a new ACL that matches nothing. 143 */ 144 145 bool 146 dns_acl_isany(dns_acl_t *acl); 147 /*%< 148 * Test whether ACL is set to "{ any; }" 149 */ 150 151 bool 152 dns_acl_isnone(dns_acl_t *acl); 153 /*%< 154 * Test whether ACL is set to "{ none; }" 155 */ 156 157 isc_result_t 158 dns_acl_merge(dns_acl_t *dest, dns_acl_t *source, bool pos); 159 /*%< 160 * Merge the contents of one ACL into another. Call dns_iptable_merge() 161 * for the IP tables, then concatenate the element arrays. 162 * 163 * If pos is set to false, then the nested ACL is to be negated. This 164 * means reverse the sense of each *positive* element or IP table node, 165 * but leave negatives alone, so as to prevent a double-negative causing 166 * an unexpected positive match in the parent ACL. 167 */ 168 169 #if DNS_ACL_TRACE 170 #define dns_acl_ref(ptr) dns_acl__ref(ptr, __func__, __FILE__, __LINE__) 171 #define dns_acl_unref(ptr) dns_acl__unref(ptr, __func__, __FILE__, __LINE__) 172 #define dns_acl_attach(ptr, ptrp) \ 173 dns_acl__attach(ptr, ptrp, __func__, __FILE__, __LINE__) 174 #define dns_acl_detach(ptrp) dns_acl__detach(ptrp, __func__, __FILE__, __LINE__) 175 ISC_REFCOUNT_TRACE_DECL(dns_acl); 176 #else 177 ISC_REFCOUNT_DECL(dns_acl); 178 #endif 179 180 bool 181 dns_acl_isinsecure(const dns_acl_t *a); 182 /*%< 183 * Return #true iff the acl 'a' is considered insecure, that is, 184 * if it contains IP addresses other than those of the local host. 185 * This is intended for applications such as printing warning 186 * messages for suspect ACLs; it is not intended for making access 187 * control decisions. We make no guarantee that an ACL for which 188 * this function returns #false is safe. 189 */ 190 191 bool 192 dns_acl_allowed(isc_netaddr_t *addr, const dns_name_t *signer, dns_acl_t *acl, 193 dns_aclenv_t *aclenv); 194 /*%< 195 * Return #true iff the 'addr', 'signer', or ECS values are 196 * permitted by 'acl' in environment 'aclenv'. 197 */ 198 199 void 200 dns_aclenv_create(isc_mem_t *mctx, dns_aclenv_t **envp); 201 /*%< 202 * Create ACL environment, setting up localhost and localnets ACLs 203 */ 204 205 void 206 dns_aclenv_copy(dns_aclenv_t *t, dns_aclenv_t *s); 207 /*%< 208 * Copy the ACLs from one ACL environment object to another. 209 * 210 * Requires: 211 *\li both 's' and 't' are valid ACL environments. 212 */ 213 214 void 215 dns_aclenv_set(dns_aclenv_t *env, dns_acl_t *localhost, dns_acl_t *localnets); 216 /*%< 217 * Attach the 'localhost' and 'localnets' arguments to 'env' ACL environment 218 */ 219 220 #if DNS_ACL_TRACE 221 #define dns_aclenv_ref(ptr) dns_aclenv__ref(ptr, __func__, __FILE__, __LINE__) 222 #define dns_aclenv_unref(ptr) \ 223 dns_aclenv__unref(ptr, __func__, __FILE__, __LINE__) 224 #define dns_aclenv_attach(ptr, ptrp) \ 225 dns_aclenv__attach(ptr, ptrp, __func__, __FILE__, __LINE__) 226 #define dns_aclenv_detach(ptrp) \ 227 dns_aclenv__detach(ptrp, __func__, __FILE__, __LINE__) 228 ISC_REFCOUNT_TRACE_DECL(dns_aclenv); 229 #else 230 ISC_REFCOUNT_DECL(dns_aclenv); 231 #endif 232 233 isc_result_t 234 dns_acl_match(const isc_netaddr_t *reqaddr, const dns_name_t *reqsigner, 235 const dns_acl_t *acl, dns_aclenv_t *env, int *match, 236 const dns_aclelement_t **matchelt); 237 /*%< 238 * General, low-level ACL matching. This is expected to 239 * be useful even for weird stuff like the topology and sortlist statements. 240 * 241 * Match the address 'reqaddr', and optionally the key name 'reqsigner', 242 * against 'acl'. 'reqsigner' may be NULL. 243 * 244 * If there is a match, '*match' will be set to an integer whose absolute 245 * value corresponds to the order in which the matching value was inserted 246 * into the ACL. For a positive match, this value will be positive; for a 247 * negative match, it will be negative. 248 * 249 * If there is no match, *match will be set to zero. 250 * 251 * If there is a match in the element list (either positive or negative) 252 * and 'matchelt' is non-NULL, *matchelt will be pointed to the matching 253 * element. 254 * 255 * 'env' points to the current ACL environment, including the 256 * current values of localhost and localnets and (if applicable) 257 * the GeoIP context. 258 * 259 * Returns: 260 *\li #ISC_R_SUCCESS Always succeeds. 261 */ 262 263 bool 264 dns_aclelement_match(const isc_netaddr_t *reqaddr, const dns_name_t *reqsigner, 265 const dns_aclelement_t *e, dns_aclenv_t *env, 266 const dns_aclelement_t **matchelt); 267 /*%< 268 * Like dns_acl_match, but matches against the single ACL element 'e' 269 * rather than a complete ACL, and returns true iff it matched. 270 * 271 * To determine whether the match was positive or negative, the 272 * caller should examine e->negative. Since the element 'e' may be 273 * a reference to a named ACL or a nested ACL, a matching element 274 * returned through 'matchelt' is not necessarily 'e' itself. 275 */ 276 277 isc_result_t 278 dns_acl_match_port_transport(const isc_netaddr_t *reqaddr, 279 const in_port_t local_port, 280 const isc_nmsocket_type_t transport, 281 const bool encrypted, const dns_name_t *reqsigner, 282 const dns_acl_t *acl, dns_aclenv_t *env, 283 int *match, const dns_aclelement_t **matchelt); 284 /*%< 285 * Like dns_acl_match, but able to match the server port and 286 * transport, as well as encryption status. 287 * 288 * Requires: 289 *\li 'reqaddr' is not 'NULL'; 290 *\li 'acl' is a valid ACL object. 291 */ 292 293 void 294 dns_acl_add_port_transports(dns_acl_t *acl, const in_port_t port, 295 const uint32_t transports, const bool encrypted, 296 const bool negative); 297 /*%< 298 * Adds a "port-transports" entry to the specified ACL. Transports 299 * are specified as a bit-set 'transports' consisting of entries 300 * defined in the isc_nmsocket_type enumeration. 301 * 302 * Requires: 303 *\li 'acl' is a valid ACL object; 304 *\li either 'port' or 'transports' is not equal to 0. 305 */ 306 307 void 308 dns_acl_merge_ports_transports(dns_acl_t *dest, dns_acl_t *source, bool pos); 309 /*%< 310 * Merges "port-transports" entries from the 'dest' ACL into 311 * the 'source' ACL. The 'pos' parameter works in a way similar to 312 * 'dns_acl_merge()'. 313 * 314 * Requires: 315 *\li 'dest' is a valid ACL object; 316 *\li 'source' is a valid ACL object. 317 */ 318 319 ISC_LANG_ENDDECLS 320