ares_dns_private.h (9783B)
1 /* MIT License 2 * 3 * Copyright (c) 2023 Brad House 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a copy 6 * of this software and associated documentation files (the "Software"), to deal 7 * in the Software without restriction, including without limitation the rights 8 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 * copies of the Software, and to permit persons to whom the Software is 10 * furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice (including the next 13 * paragraph) shall be included in all copies or substantial portions of the 14 * Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 * 24 * SPDX-License-Identifier: MIT 25 */ 26 #ifndef __ARES_DNS_PRIVATE_H 27 #define __ARES_DNS_PRIVATE_H 28 29 ares_status_t ares_dns_record_duplicate_ex(ares_dns_record_t **dest, 30 const ares_dns_record_t *src); 31 ares_bool_t ares_dns_rec_allow_name_comp(ares_dns_rec_type_t type); 32 ares_bool_t ares_dns_opcode_isvalid(ares_dns_opcode_t opcode); 33 ares_bool_t ares_dns_rcode_isvalid(ares_dns_rcode_t rcode); 34 ares_bool_t ares_dns_flags_arevalid(unsigned short flags); 35 ares_bool_t ares_dns_rec_type_isvalid(ares_dns_rec_type_t type, 36 ares_bool_t is_query); 37 ares_bool_t ares_dns_class_isvalid(ares_dns_class_t qclass, 38 ares_dns_rec_type_t type, 39 ares_bool_t is_query); 40 ares_bool_t ares_dns_section_isvalid(ares_dns_section_t sect); 41 ares_status_t ares_dns_rr_set_str_own(ares_dns_rr_t *dns_rr, 42 ares_dns_rr_key_t key, char *val); 43 ares_status_t ares_dns_rr_set_bin_own(ares_dns_rr_t *dns_rr, 44 ares_dns_rr_key_t key, unsigned char *val, 45 size_t len); 46 ares_status_t ares_dns_rr_set_abin_own(ares_dns_rr_t *dns_rr, 47 ares_dns_rr_key_t key, 48 ares_dns_multistring_t *strs); 49 ares_status_t ares_dns_rr_set_opt_own(ares_dns_rr_t *dns_rr, 50 ares_dns_rr_key_t key, unsigned short opt, 51 unsigned char *val, size_t val_len); 52 ares_status_t ares_dns_record_rr_prealloc(ares_dns_record_t *dnsrec, 53 ares_dns_section_t sect, size_t cnt); 54 ares_dns_rr_t *ares_dns_get_opt_rr(ares_dns_record_t *rec); 55 const ares_dns_rr_t *ares_dns_get_opt_rr_const(const ares_dns_record_t *rec); 56 void ares_dns_record_ttl_decrement(ares_dns_record_t *dnsrec, 57 unsigned int ttl_decrement); 58 59 /* Same as ares_dns_write() but appends to an existing buffer object */ 60 ares_status_t ares_dns_write_buf(const ares_dns_record_t *dnsrec, 61 ares_buf_t *buf); 62 63 /* Same as ares_dns_write_buf(), but prepends a 16bit length */ 64 ares_status_t ares_dns_write_buf_tcp(const ares_dns_record_t *dnsrec, 65 ares_buf_t *buf); 66 67 /*! Create a DNS record object for a query. The arguments are the same as 68 * those for ares_create_query(). 69 * 70 * \param[out] dnsrec DNS record object to create. 71 * \param[in] name NUL-terminated name for the query. 72 * \param[in] dnsclass Class for the query. 73 * \param[in] type Type for the query. 74 * \param[in] id Identifier for the query. 75 * \param[in] flags Flags for the query. 76 * \param[in] max_udp_size Maximum size of a UDP packet for EDNS. 77 * \return ARES_SUCCESS on success, otherwise an error code. 78 */ 79 ares_status_t 80 ares_dns_record_create_query(ares_dns_record_t **dnsrec, const char *name, 81 ares_dns_class_t dnsclass, 82 ares_dns_rec_type_t type, unsigned short id, 83 ares_dns_flags_t flags, size_t max_udp_size); 84 85 /*! Convert the RCODE and ANCOUNT from a DNS query reply into a status code. 86 * 87 * \param[in] rcode The RCODE from the reply. 88 * \param[in] ancount The ANCOUNT from the reply. 89 * \return An appropriate status code. 90 */ 91 ares_status_t ares_dns_query_reply_tostatus(ares_dns_rcode_t rcode, 92 size_t ancount); 93 94 struct ares_dns_qd { 95 char *name; 96 ares_dns_rec_type_t qtype; 97 ares_dns_class_t qclass; 98 }; 99 100 typedef struct { 101 struct in_addr addr; 102 } ares_dns_a_t; 103 104 typedef struct { 105 char *nsdname; 106 } ares_dns_ns_t; 107 108 typedef struct { 109 char *cname; 110 } ares_dns_cname_t; 111 112 typedef struct { 113 char *mname; 114 char *rname; 115 unsigned int serial; 116 unsigned int refresh; 117 unsigned int retry; 118 unsigned int expire; 119 unsigned int minimum; 120 } ares_dns_soa_t; 121 122 typedef struct { 123 char *dname; 124 } ares_dns_ptr_t; 125 126 typedef struct { 127 char *cpu; 128 char *os; 129 } ares_dns_hinfo_t; 130 131 typedef struct { 132 unsigned short preference; 133 char *exchange; 134 } ares_dns_mx_t; 135 136 typedef struct { 137 ares_dns_multistring_t *strs; 138 } ares_dns_txt_t; 139 140 typedef struct { 141 unsigned short type_covered; 142 unsigned char algorithm; 143 unsigned char labels; 144 unsigned int original_ttl; 145 unsigned int expiration; 146 unsigned int inception; 147 unsigned short key_tag; 148 char *signers_name; 149 unsigned char *signature; 150 size_t signature_len; 151 } ares_dns_sig_t; 152 153 typedef struct { 154 struct ares_in6_addr addr; 155 } ares_dns_aaaa_t; 156 157 typedef struct { 158 unsigned short priority; 159 unsigned short weight; 160 unsigned short port; 161 char *target; 162 } ares_dns_srv_t; 163 164 typedef struct { 165 unsigned short order; 166 unsigned short preference; 167 char *flags; 168 char *services; 169 char *regexp; 170 char *replacement; 171 } ares_dns_naptr_t; 172 173 typedef struct { 174 unsigned short opt; 175 unsigned char *val; 176 size_t val_len; 177 } ares_dns_optval_t; 178 179 typedef struct { 180 unsigned short udp_size; /*!< taken from class */ 181 unsigned char version; /*!< taken from bits 8-16 of ttl */ 182 unsigned short flags; /*!< Flags, remaining 16 bits, though only 183 * 1 currently defined */ 184 ares_array_t *options; /*!< Type is ares_dns_optval_t */ 185 } ares_dns_opt_t; 186 187 typedef struct { 188 unsigned char cert_usage; 189 unsigned char selector; 190 unsigned char match; 191 unsigned char *data; 192 size_t data_len; 193 } ares_dns_tlsa_t; 194 195 typedef struct { 196 unsigned short priority; 197 char *target; 198 ares_array_t *params; /*!< Type is ares_dns_optval_t */ 199 } ares_dns_svcb_t; 200 201 typedef struct { 202 unsigned short priority; 203 unsigned short weight; 204 char *target; 205 } ares_dns_uri_t; 206 207 typedef struct { 208 unsigned char critical; 209 char *tag; 210 unsigned char *value; 211 size_t value_len; 212 } ares_dns_caa_t; 213 214 /*! Raw, unparsed RR data */ 215 typedef struct { 216 unsigned short type; /*!< Not ares_rec_type_t because it likely isn't one 217 * of those values since it wasn't parsed */ 218 unsigned char *data; /*!< Raw RR data */ 219 size_t length; /*!< Length of raw RR data */ 220 } ares_dns_raw_rr_t; 221 222 /*! DNS RR data structure */ 223 struct ares_dns_rr { 224 ares_dns_record_t *parent; 225 char *name; 226 ares_dns_rec_type_t type; 227 ares_dns_class_t rclass; 228 unsigned int ttl; 229 230 union { 231 ares_dns_a_t a; 232 ares_dns_ns_t ns; 233 ares_dns_cname_t cname; 234 ares_dns_soa_t soa; 235 ares_dns_ptr_t ptr; 236 ares_dns_hinfo_t hinfo; 237 ares_dns_mx_t mx; 238 ares_dns_txt_t txt; 239 ares_dns_sig_t sig; 240 ares_dns_aaaa_t aaaa; 241 ares_dns_srv_t srv; 242 ares_dns_naptr_t naptr; 243 ares_dns_opt_t opt; 244 ares_dns_tlsa_t tlsa; 245 ares_dns_svcb_t svcb; 246 ares_dns_svcb_t https; /*!< https is a type of svcb, so this is right */ 247 ares_dns_uri_t uri; 248 ares_dns_caa_t caa; 249 ares_dns_raw_rr_t raw_rr; 250 } r; 251 }; 252 253 /*! DNS data structure */ 254 struct ares_dns_record { 255 unsigned short id; /*!< DNS query id */ 256 unsigned short flags; /*!< One or more ares_dns_flags_t */ 257 ares_dns_opcode_t opcode; /*!< DNS Opcode */ 258 ares_dns_rcode_t rcode; /*!< DNS RCODE */ 259 unsigned short raw_rcode; /*!< Raw rcode, used to ultimately form real 260 * rcode after reading OPT record if it 261 * exists */ 262 unsigned int ttl_decrement; /*!< Special case to apply to writing out 263 * this record, where it will decrement 264 * the ttl of any resource records by 265 * this amount. Used for cache */ 266 267 ares_array_t *qd; /*!< Type is ares_dns_qd_t */ 268 ares_array_t *an; /*!< Type is ares_dns_rr_t */ 269 ares_array_t *ns; /*!< Type is ares_dns_rr_t */ 270 ares_array_t *ar; /*!< Type is ares_dns_rr_t */ 271 }; 272 273 #endif