ServiceRegistration/dns-msg.h

   1 /* dns-msg.h
   2  *
   3  * Copyright (c) 2018 Apple Computer, Inc. All rights reserved.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  *
  17  * Lightweight framework for generating, sending, and unpacking DNS messages.
  18  * Definitions...
  19  */
  20
  21 #ifndef __DNS_MSG_H
  22 #define __DNS_MSG_H
  23
  24 #ifndef DNS_MAX_UDP_PAYLOAD
  25 #define DNS_MAX_UDP_PAYLOAD 1410
  26 #endif
  27
  28 #define DNS_HEADER_SIZE           12
  29 #define DNS_DATA_SIZE             (DNS_MAX_UDP_PAYLOAD - DNS_HEADER_SIZE)
  30 #define DNS_MAX_POINTER           ((2 << 14) - 1)
  31 #define DNS_MAX_LABEL_SIZE        63
  32 #define DNS_MAX_NAME_SIZE             255
  33 #define DNS_MAX_NAME_SIZE_ESCAPED 1009
  34
  35 typedef struct dns_wire dns_wire_t;
  36 struct dns_wire {
  37     uint16_t id;
  38     uint16_t bitfield;
  39     uint16_t qdcount;
  40     uint16_t ancount;
  41     uint16_t nscount;
  42     uint16_t arcount;
  43     uint8_t data[DNS_DATA_SIZE];
  44 };
  45
  46 typedef struct dns_towire_state dns_towire_state_t;
  47 struct dns_towire_state {
  48         dns_wire_t *NULLABLE message;
  49     uint8_t *NONNULL p;
  50     uint8_t *NONNULL lim;
  51     uint8_t *NULLABLE p_rdlength;
  52     uint8_t *NULLABLE p_opt;
  53     int error;
  54 };
  55
  56 typedef struct dns_transaction dns_transaction_t;
  57 struct dns_transaction {
  58     dns_transaction_t *NULLABLE next;
  59     dns_towire_state_t towire;
  60     dns_wire_t *NULLABLE response;
  61     int response_length;
  62     int sock;
  63 };
  64
  65 typedef struct dns_name_pointer dns_name_pointer_t;
  66 struct dns_name_pointer {
  67     uint8_t *NONNULL message_start;
  68     uint8_t *NONNULL name_start;
  69     int num_labels;
  70     int length;
  71 };
  72
  73 typedef void (*dns_response_callback_t)(dns_transaction_t *NONNULL txn);
  74
  75 typedef struct dns_label dns_label_t;
  76 typedef dns_label_t dns_name_t;
  77 struct dns_label {
  78     dns_label_t *NULLABLE next;
  79     uint8_t len;
  80     char data[DNS_MAX_LABEL_SIZE];
  81 };
  82
  83 typedef struct dns_txt_element dns_txt_element_t;
  84 struct dns_txt_element {
  85     dns_txt_element_t *NULLABLE next;
  86     uint8_t len;
  87     char data[0];
  88 };
  89
  90 typedef struct dns_rdata_unparsed dns_rdata_unparsed_t;
  91 struct dns_rdata_unparsed {
  92     uint8_t *NULLABLE data;
  93     uint16_t len;
  94 };
  95
  96 typedef struct dns_rdata_single_name dns_rdata_ptr_t;
  97 typedef struct dns_rdata_single_name dns_rdata_cname_t;
  98 struct dns_rdata_single_name {
  99     dns_label_t *NONNULL name;
 100 };
 101
 102 typedef struct dns_rdata_a dns_rdata_a_t;
 103 struct dns_rdata_a {
 104     struct in_addr *NONNULL addrs;
 105     int num;
 106 };
 107
 108 typedef struct dns_rdata_aaaa dns_rdata_aaaa_t;
 109 struct dns_rdata_aaaa {
 110     struct in6_addr *NONNULL addrs;
 111     int num;
 112 } aaaa;
 113
 114 typedef struct dns_rdata_srv dns_rdata_srv_t;
 115 struct dns_rdata_srv {
 116     dns_label_t *NONNULL name;
 117     uint16_t priority;
 118     uint16_t weight;
 119     uint16_t port;
 120 } srv;
 121
 122 typedef struct dns_rdata_sig dns_rdata_sig_t;
 123 struct dns_rdata_sig {
 124     uint16_t type;
 125     uint8_t algorithm;
 126     uint8_t label;
 127     uint32_t rrttl;
 128     uint32_t expiry;
 129     uint32_t inception;
 130     uint16_t key_tag;
 131     dns_label_t *NONNULL signer;
 132     int start;
 133     int len;
 134     uint8_t *NONNULL signature;
 135 } sig;
 136
 137 typedef struct dns_rdata_key dns_rdata_key_t;
 138 struct dns_rdata_key {
 139     uint16_t flags;
 140     uint8_t protocol;
 141     uint8_t algorithm;
 142     int len;
 143     uint8_t *NONNULL key;
 144 } key;
 145
 146 typedef struct dns_rr dns_rr_t;
 147 struct dns_rr {
 148     dns_label_t *NONNULL name;
 149     uint16_t type;
 150     uint16_t qclass;
 151     uint32_t ttl;
 152     union {
 153         dns_rdata_unparsed_t unparsed;
 154         dns_rdata_ptr_t ptr;
 155         dns_rdata_cname_t cname;
 156         dns_rdata_a_t a;
 157         dns_rdata_aaaa_t aaaa;
 158         dns_rdata_srv_t srv;
 159         dns_txt_element_t *NONNULL txt;
 160         dns_rdata_sig_t sig;
 161         dns_rdata_key_t key;
 162     } data;
 163 };
 164
 165 typedef struct dns_edns0 dns_edns0_t;
 166 struct dns_edns0 {
 167     dns_edns0_t *NULLABLE next;
 168     uint16_t length;
 169     uint8_t data[0];
 170 };
 171
 172 typedef struct dns_message dns_message_t;
 173 struct dns_message {
 174     dns_wire_t *NULLABLE wire;
 175     int qdcount, ancount, nscount, arcount;
 176     dns_rr_t *NULLABLE questions;
 177     dns_rr_t *NULLABLE answers;
 178     dns_rr_t *NULLABLE authority;
 179     dns_rr_t *NULLABLE additional;
 180     dns_edns0_t *NULLABLE edns0;
 181 };
 182
 183 // Masks for bitfield data
 184 #define dns_qr_mask     0x8000
 185 #define dns_opcode_mask 0x7800
 186 #define dns_flags_mask  0x07f0
 187 #define dns_rcode_mask  0x000f
 188
 189 // Shifts for bitfield data
 190 #define dns_qr_shift     15
 191 #define dns_opcode_shift 11
 192 #define dns_rcode_shift  0
 193
 194 // Booleans
 195 #define dns_flags_aa 0x0400
 196 #define dns_flags_tc 0x0200
 197 #define dns_flags_rd 0x0100
 198 #define dns_flags_ra 0x0080
 199 #define dns_flags_ad 0x0020
 200 #define dns_flags_cd 0x0010
 201
 202 // Getters
 203 #define dns_qr_get(w) ((ntohs((w)->bitfield) & dns_qr_mask) >> dns_qr_shift)
 204 #define dns_opcode_get(w) ((ntohs((w)->bitfield) & dns_opcode_mask) >> dns_opcode_shift)
 205 #define dns_rcode_get(w) ((ntohs((w)->bitfield) & dns_rcode_mask) >> dns_rcode_shift)
 206
 207 // Setters
 208 #define dns_qr_set(w, value) ((w)->bitfield = htons(((ntohs((w)->bitfield) & ~dns_qr_mask) | \
 209                                                      ((value) << dns_qr_shift))))
 210 #define dns_opcode_set(w, value) ((w)->bitfield = htons(((ntohs((w)->bitfield) & ~dns_opcode_mask) | \
 211                                                          ((value) << dns_opcode_shift))))
 212 #define dns_rcode_set(w, value) ((w)->bitfield = htons(((ntohs((w)->bitfield) & ~dns_rcode_mask) | \
 213                                                         ((value) << dns_rcode_shift))))
 214
 215 // Query/Response
 216 #define dns_qr_query           0
 217 #define dns_qr_response        1
 218
 219 // Opcodes
 220 #define dns_opcode_query       0
 221 #define dns_opcode_iquery      1
 222 #define dns_opcode_status      2
 223 #define dns_opcode_notify      4
 224 #define dns_opcode_update      5
 225 #define dns_opcode_dso         6
 226
 227 // Response Codes
 228 #define dns_rcode_noerror      0 // [RFC1035] No Error
 229 #define dns_rcode_formerr      1 // [RFC1035] Format Error
 230 #define dns_rcode_servfail     2 // [RFC1035] Server Failure
 231 #define dns_rcode_nxdomain     3 // [RFC1035] Non-Existent Domain
 232 #define dns_rcode_notimp       4 // [RFC1035] Not Implemented
 233 #define dns_rcode_refused      5 // [RFC1035] Query Refused
 234 #define dns_rcode_yxdomain     6 // [RFC2136][RFC6672] Name Exists when it should not
 235 #define dns_rcode_yxrrset      7 // [RFC2136] RR Set Exists when it should not
 236 #define dns_rcode_nxrrset      8 // [RFC2136] RR Set that should exist does not
 237 #define dns_rcode_notauth      9 // [RFC2136] Server Not Authoritative for zone, or [RFC2845] Not Authorized
 238 #define dns_rcode_notzone     10 // [RFC2136] Name not contained in zone
 239 #define dns_rcode_dsotypeni   11 // [RFCTBD draft-ietf-dnsop-session-signal] DSO-Type Not Implemented
 240 #define dns_rcode_badvers     16 // [RFC6891] Bad OPT Version, or [RFC2845] TSIG Signature Failure
 241 #define dns_rcode_badkey      17 // [RFC2845] Key not recognized
 242 #define dns_rcode_badtime     18 // [RFC2845] Signature out of time window
 243 #define dns_rcode_badmode     19 // [RFC2930] Bad TKEY Mode
 244 #define dns_rcode_badname     20 // [RFC2930] Duplicate key name
 245 #define dns_rcode_badalg      21 // [RFC2930] Algorithm not supported
 246 #define dns_rcode_badtrunc    22 // [RFC4635] Bad Truncation
 247 #define dns_rcode_badcookie   23 // [RFC7873] Bad/missing Server Cookie
 248
 249 #define dns_qclass_in          1 // [RFC1035] Internet (IN)
 250 #define dns_qclass_chaos       3 // [D. Moon, "Chaosnet"] Chaosnet (MIT)
 251 #define dns_qclass_hesiod      4 // [MIT Project Athena Technical Plan] Hesiod service
 252 #define dns_qclass_none      254 // [RFC2136] NONE (delete, or not in use)
 253 #define dns_qclass_any       255 // [RFC1035] ANY (wildcard)
 254
 255 #define dns_rrtype_a           1 // [RFC1035] a host address
 256 #define dns_rrtype_ns          2 // [RFC1035] an authoritative name server
 257 #define dns_rrtype_md          3 // [RFC1035] a mail destination (OBSOLETE - use MX)
 258 #define dns_rrtype_mf          4 // [RFC1035] a mail forwarder (OBSOLETE - use MX)
 259 #define dns_rrtype_cname       5 // [RFC1035] the canonical name for an alias
 260 #define dns_rrtype_soa         6 // [RFC1035] marks the start of a zone of authority
 261 #define dns_rrtype_mb          7 // [RFC1035] a mailbox domain name (EXPERIMENTAL)
 262 #define dns_rrtype_mg          8 // [RFC1035] a mail group member (EXPERIMENTAL)
 263 #define dns_rrtype_mr          9 // [RFC1035] a mail rename domain name (EXPERIMENTAL)
 264 #define dns_rrtype_null       10 // [RFC1035]    a null RR (EXPERIMENTAL)
 265 #define dns_rrtype_wks        11 // [RFC1035]    a well known service description
 266 #define dns_rrtype_ptr        12 // [RFC1035]    a domain name pointer
 267 #define dns_rrtype_hinfo      13 // [RFC1035]    host information
 268 #define dns_rrtype_minfo      14 // [RFC1035]    mailbox or mail list information
 269 #define dns_rrtype_mx         15 // [RFC1035]    mail exchange
 270 #define dns_rrtype_txt        16 // [RFC1035] text strings
 271 #define dns_rrtype_rp         17 // [RFC1183] for Responsible Person
 272 #define dns_rrtype_afsdb      18 // [RFC1183,RFC5864] for AFS Data Base location
 273 #define dns_rrtype_x25        19 // [RFC1183] for X.25 PSDN address
 274 #define dns_rrtype_isdn       20 // [RFC1183] for ISDN address
 275 #define dns_rrtype_rt         21 // [RFC1183] for Route Through
 276 #define dns_rrtype_nsap       22 // [RFC1706] for NSAP address, NSAP style A record
 277 #define dns_rrtype_nsap_ptr   23 // [RFC1348,RFC1637,RFC1706] for domain name pointer, NSAP style
 278 #define dns_rrtype_sig        24 // [RFC4034,RFC3755,RFC2535,RFC2536,RFC2537,RFC2931,RFC3110,RFC3008]
 279 #define dns_rrtype_key        25 // [RFC4034,RFC3755,RFC2535,RFC2536,RFC2537,RFC2539,RFC3008,RFC3110]
 280 #define dns_rrtype_px         26 // [RFC2163] X.400 mail mapping information
 281 #define dns_rrtype_gpos       27 // [RFC1712] Geographical Position
 282 #define dns_rrtype_aaaa       28 // [RFC3596] IP6 Address
 283 #define dns_rrtype_loc        29 // [RFC1876] Location Information
 284 #define dns_rrtype_nxt        30 // [RFC3755] [RFC2535] Next Domain (OBSOLETE)
 285 #define dns_rrtype_eid        31 // [http://ana-3.lcs.mit.edu/~jnc/nimrod/dns.txt] Endpoint Identifier
 286 #define dns_rrtype_nimloc     32 // [http://ana-3.lcs.mit.edu/~jnc/nimrod/dns.txt] Nimrod Locator
 287 #define dns_rrtype_srv        33 // [RFC2782] Server Selection
 288 #define dns_rrtype_atma       34 // ["ATM Name System, V2.0"] ATM Address
 289 #define dns_rrtype_naptr      35 // [RFC2915] [RFC2168] [RFC3403] Naming Authority Pointer
 290 #define dns_rrtype_kx         36 // [RFC2230] Key Exchanger
 291 #define dns_rrtype_cert       37 // [RFC4398] CERT
 292 #define dns_rrtype_a6         38 // [RFC3226] [RFC2874] [RFC6563]        A6 (OBSOLETE - use AAAA)
 293 #define dns_rrtype_dname      39 // [RFC6672]
 294 #define dns_rrtype_sink       40 // [http://tools.ietf.org/html/draft-eastlake-kitchen-sink]
 295 #define dns_rrtype_opt        41 // [RFC6891] [RFC3225]
 296 #define dns_rrtype_apl        42 // [RFC3123]
 297 #define dns_rrtype_ds         43 // [RFC4034] [RFC3658] Delegation Signer
 298 #define dns_rrtype_sshfp      44 // [RFC4255] SSH Key Fingerprint
 299 #define dns_rrtype_ipseckey   45 // [RFC4025]
 300 #define dns_rrtype_rrsig      46 // [RFC4034] [RFC3755]
 301 #define dns_rrtype_nsec       47 // [RFC4034] [RFC3755]
 302 #define dns_rrtype_dnskey     48 // [RFC4034] [RFC3755]
 303 #define dns_rrtype_dhcid      49 // [RFC4701] DHCID
 304 #define dns_rrtype_nsec3      50 // [RFC5155] NSEC3
 305 #define dns_rrtype_nsec3param 51 // [RFC5155] NSEC3PARAM
 306 #define dns_rrtype_tlsa       52 // [RFC6698] TLSA
 307 #define dns_rrtype_smimea     53 // [RFC8162] S/MIME cert association
 308 #define dns_rrtype_hip        55 // Host Identity Protocol
 309 #define dns_rrtype_ninfo      56 // [Jim_Reid] NINFO/ninfo-completed-template
 310 #define dns_rrtype_rkey       57 // [Jim_Reid] RKEY/rkey-completed-template
 311 #define dns_rrtype_talink     58 // [Wouter_Wijngaards] Trust Anchor LINK
 312 #define dns_rrtype_cds        59 // [RFC7344] Child DS
 313 #define dns_rrtype_cdnskey    60 // [RFC7344]   DNSKEY(s) the Child wants reflected in DS
 314 #define dns_rrtype_openpgpkey 61 // [RFC7929]   OpenPGP Key
 315 #define dns_rrtype_csync      62 // [RFC7477] Child-To-Parent Synchronization
 316 #define dns_rrtype_spf        99 // [RFC7208]
 317 #define dns_rrtype_uinfo     100 // [IANA-Reserved]
 318 #define dns_rrtype_uid       101 // [IANA-Reserved]
 319 #define dns_rrtype_gid       102 // [IANA-Reserved]
 320 #define dns_rrtype_unspec    103 // [IANA-Reserved]
 321 #define dns_rrtype_nid       104 // [RFC6742]
 322 #define dns_rrtype_l32       105 // [RFC6742]
 323 #define dns_rrtype_l64       106 // [RFC6742]
 324 #define dns_rrtype_lp        107 // [RFC6742]
 325 #define dns_rrtype_eui48     108 // an EUI-48 address [RFC7043]
 326 #define dns_rrtype_eui64     109 // an EUI-64 address [RFC7043]
 327 #define dns_rrtype_tkey      249 // Transaction Key     [RFC2930]
 328 #define dns_rrtype_tsig      250 // Transaction Signature [RFC2845]
 329 #define dns_rrtype_ixfr      251 // incremental transfer        [RFC1995]
 330 #define dns_rrtype_axfr      252 // transfer of an entire zone [RFC1035][RFC5936]
 331 #define dns_rrtype_mailb     253 // mailbox-related RRs (MB, MG or MR) [RFC1035]
 332 #define dns_rrtype_maila     254 // mail agent RRs (OBSOLETE - see MX) [RFC1035]
 333 #define dns_rrtype_any       255 // A request for some or all records the server has available
 334 #define dns_rrtype_uri       256 // URI [RFC7553]       URI/uri-completed-template
 335 #define dns_rrtype_caa       257 // Certification Authority Restriction [RFC6844]
 336 #define dns_rrtype_avc       258 // Application Visibility and Control [Wolfgang_Riedel]
 337 #define dns_rrtype_doa       259 // Digital Object Architecture [draft-durand-doa-over-dns]
 338
 339 #define dns_opt_llq            1 // On-hold [http://files.dns-sd.org/draft-sekar-dns-llq.txt]
 340 #define dns_opt_update_lease   2 // On-hold     [http://files.dns-sd.org/draft-sekar-dns-ul.txt]
 341 #define dns_opt_nsid           3 // [RFC5001]
 342 #define dns_opt_owner          4 // [draft-cheshire-edns0-owner-option]
 343 #define dns_opt_dau            5 // [RFC6975]
 344 #define dns_opt_dhu            6 // [RFC6975]
 345 #define dns_opt_n3u            7 // [RFC6975]
 346 #define dns_opt_client_subnet  8 // [RFC7871]
 347 #define dns_opt_expire         9 // [RFC7314]
 348 #define dns_opt_cookie        10 // [RFC7873]
 349 #define dns_opt_keepalive     11 // [RFC7828]
 350 #define dns_opt_padding       12 // [RFC7830]
 351 #define dns_opt_chain         13 // [RFC7901]
 352 #define dns_opt_key_tag       14 // [RFC8145]
 353
 354 // towire.c:
 355
 356 uint16_t srp_random16(void);
 357 void dns_name_to_wire(dns_name_pointer_t *NULLABLE r_pointer,
 358                       dns_towire_state_t *NONNULL txn,
 359                       const char *NONNULL name);
 360 void dns_full_name_to_wire(dns_name_pointer_t *NULLABLE r_pointer,
 361                            dns_towire_state_t *NONNULL txn,
 362                            const char *NONNULL name);
 363 void dns_pointer_to_wire(dns_name_pointer_t *NULLABLE r_pointer,
 364                          dns_towire_state_t *NONNULL txn,
 365                          dns_name_pointer_t *NONNULL pointer);
 366 void dns_u8_to_wire(dns_towire_state_t *NONNULL txn,
 367                     uint8_t val);
 368 void dns_u16_to_wire(dns_towire_state_t *NONNULL txn,
 369                       uint16_t val);
 370 void dns_u32_to_wire(dns_towire_state_t *NONNULL txn,
 371                       uint32_t val);
 372 void dns_ttl_to_wire(dns_towire_state_t *NONNULL txn,
 373                      int32_t val);
 374 void dns_rdlength_begin(dns_towire_state_t *NONNULL txn);
 375 void dns_rdlength_end(dns_towire_state_t *NONNULL txn);
 376 void dns_rdata_a_to_wire(dns_towire_state_t *NONNULL txn,
 377                          const char *NONNULL ip_address);
 378 void dns_rdata_aaaa_to_wire(dns_towire_state_t *NONNULL txn,
 379                             const char *NONNULL ip_address);
 380 uint16_t dns_rdata_key_to_wire(dns_towire_state_t *NONNULL txn,
 381                                unsigned key_type,
 382                                unsigned name_type,
 383                                unsigned signatory,
 384                                srp_key_t *NONNULL key);
 385 void dns_rdata_txt_to_wire(dns_towire_state_t *NONNULL txn,
 386                            const char *NONNULL txt_record);
 387 void dns_rdata_raw_data_to_wire(dns_towire_state_t *NONNULL txn, const void *NONNULL raw_data, size_t length);
 388 void dns_edns0_header_to_wire(dns_towire_state_t *NONNULL txn,
 389                               int mtu,
 390                               int xrcode,
 391                               int version,
 392                               int DO);
 393 void dns_edns0_option_begin(dns_towire_state_t *NONNULL txn);
 394 void dns_edns0_option_end(dns_towire_state_t *NONNULL txn);
 395 void dns_sig0_signature_to_wire(dns_towire_state_t *NONNULL txn,
 396                                 srp_key_t *NONNULL key, uint16_t key_tag,
 397                                 dns_name_pointer_t *NONNULL signer,
 398                                 const char *NONNULL signer_fqdn);
 399 int dns_send_to_server(dns_transaction_t *NONNULL txn,
 400                        const char *NONNULL anycast_address, uint16_t port,
 401                        dns_response_callback_t NONNULL callback);
 402
 403 // fromwire.c:
 404 dns_label_t *NULLABLE dns_label_parse(const uint8_t *NONNULL buf, unsigned mlen, unsigned *NONNULL offp);
 405 bool dns_opt_parse(dns_edns0_t *NONNULL *NULLABLE ret, dns_rr_t *NONNULL rrset);
 406 bool dns_name_parse(dns_label_t *NONNULL *NULLABLE ret, const uint8_t *NONNULL buf, unsigned len,
 407                     unsigned *NONNULL offp, unsigned base);
 408 bool dns_u8_parse(const uint8_t *NONNULL buf, unsigned len, unsigned *NONNULL offp, uint8_t *NONNULL ret);
 409 bool dns_u16_parse(const uint8_t *NONNULL buf, unsigned len, unsigned *NONNULL offp, uint16_t *NONNULL ret);
 410 bool dns_u32_parse(const uint8_t *NONNULL buf, unsigned len, unsigned *NONNULL offp, uint32_t *NONNULL ret);
 411 bool dns_rdata_parse_data(dns_rr_t *NONNULL rr, const uint8_t *NONNULL buf, unsigned *NONNULL offp,
 412                           unsigned target, unsigned rdlen, unsigned rrstart);
 413 bool dns_rr_parse(dns_rr_t *NONNULL rrset,
 414                   const uint8_t *NONNULL buf, unsigned len, unsigned *NONNULL offp, bool rrdata_permitted);
 415 void dns_name_free(dns_label_t *NONNULL name);
 416 void dns_rrdata_free(dns_rr_t *NONNULL rr);
 417 void dns_message_free(dns_message_t *NONNULL message);
 418 bool dns_rdata_parse_data(dns_rr_t *NONNULL rr, const uint8_t *NONNULL buf, unsigned *NONNULL offp,
 419                           unsigned target, unsigned rdlen, unsigned rrstart);
 420 bool dns_wire_parse(dns_message_t *NONNULL *NULLABLE ret, dns_wire_t *NONNULL message, unsigned len);
 421 bool dns_names_equal(dns_label_t *NONNULL name1, dns_label_t *NONNULL name2);
 422 const char *NONNULL dns_name_print(dns_name_t *NONNULL name, char *NONNULL buf, int bufmax);
 423 bool dns_names_equal_text(dns_label_t *NONNULL name1, const char *NONNULL name2);
 424 size_t dns_name_wire_length(dns_label_t *NONNULL name);
 425 size_t dns_name_to_wire_canonical(uint8_t *NONNULL buf, size_t max, dns_label_t *NONNULL name);
 426 #endif // _DNS_MSG_H
 427
 428 // Local Variables:
 429 // mode: C
 430 // tab-width: 4
 431 // c-file-style: "bsd"
 432 // c-basic-offset: 4
 433 // fill-column: 108
 434 // indent-tabs-mode: nil
 435 // End: