1 /* -*- Mode: C; tab-width: 4 -*- 2 * 3 * Copyright (c) 2003-2004, Apple Computer, Inc. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of its 14 * contributors may be used to endorse or promote products derived from this 15 * software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 26 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef _DNS_SD_H 30 #define _DNS_SD_H 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 /* standard calling convention under Win32 is __stdcall */ 37 /* Note: When compiling Intel EFI (Extensible Firmware Interface) under MS Visual Studio, the */ 38 /* _WIN32 symbol is defined by the compiler even though it's NOT compiling code for Windows32 */ 39 #if defined(_WIN32) && !defined(EFI32) && !defined(EFI64) 40 #define DNSSD_API __stdcall 41 #else 42 #define DNSSD_API 43 #endif 44 45 /* stdint.h does not exist on FreeBSD 4.x; its types are defined in sys/types.h instead */ 46 #if defined(__FreeBSD__) && (__FreeBSD__ < 5) 47 #include <sys/types.h> 48 49 /* Likewise, on Sun, standard integer types are in sys/types.h */ 50 #elif defined(__sun__) 51 #include <sys/types.h> 52 53 /* EFI does not have stdint.h, or anything else equivalent */ 54 #elif defined(EFI32) || defined(EFI64) 55 typedef UINT8 uint8_t; 56 typedef INT8 int8_t; 57 typedef UINT16 uint16_t; 58 typedef INT16 int16_t; 59 typedef UINT32 uint32_t; 60 typedef INT32 int32_t; 61 62 /* Windows has its own differences */ 63 #elif defined(_WIN32) 64 #include <windows.h> 65 #define _UNUSED 66 #define bzero(a, b) memset(a, 0, b) 67 #ifndef _MSL_STDINT_H 68 typedef UINT8 uint8_t; 69 typedef INT8 int8_t; 70 typedef UINT16 uint16_t; 71 typedef INT16 int16_t; 72 typedef UINT32 uint32_t; 73 typedef INT32 int32_t; 74 #endif 75 76 /* All other Posix platforms use stdint.h */ 77 #else 78 #include <stdint.h> 79 #endif 80 81 /* DNSServiceRef, DNSRecordRef 82 * 83 * Opaque internal data types. 84 * Note: client is responsible for serializing access to these structures if 85 * they are shared between concurrent threads. 86 */ 87 88 typedef struct _DNSServiceRef_t *DNSServiceRef; 89 typedef struct _DNSRecordRef_t *DNSRecordRef; 90 91 /* General flags used in functions defined below */ 92 enum 93 { 94 kDNSServiceFlagsMoreComing = 0x1, 95 /* MoreComing indicates to a callback that at least one more result is 96 * queued and will be delivered following immediately after this one. 97 * Applications should not update their UI to display browse 98 * results when the MoreComing flag is set, because this would 99 * result in a great deal of ugly flickering on the screen. 100 * Applications should instead wait until until MoreComing is not set, 101 * and then update their UI. 102 * When MoreComing is not set, that doesn't mean there will be no more 103 * answers EVER, just that there are no more answers immediately 104 * available right now at this instant. If more answers become available 105 * in the future they will be delivered as usual. 106 */ 107 108 kDNSServiceFlagsAdd = 0x2, 109 kDNSServiceFlagsDefault = 0x4, 110 /* Flags for domain enumeration and browse/query reply callbacks. 111 * "Default" applies only to enumeration and is only valid in 112 * conjuction with "Add". An enumeration callback with the "Add" 113 * flag NOT set indicates a "Remove", i.e. the domain is no longer 114 * valid. 115 */ 116 117 kDNSServiceFlagsNoAutoRename = 0x8, 118 /* Flag for specifying renaming behavior on name conflict when registering 119 * non-shared records. By default, name conflicts are automatically handled 120 * by renaming the service. NoAutoRename overrides this behavior - with this 121 * flag set, name conflicts will result in a callback. The NoAutorename flag 122 * is only valid if a name is explicitly specified when registering a service 123 * (i.e. the default name is not used.) 124 */ 125 126 kDNSServiceFlagsShared = 0x10, 127 kDNSServiceFlagsUnique = 0x20, 128 /* Flag for registering individual records on a connected 129 * DNSServiceRef. Shared indicates that there may be multiple records 130 * with this name on the network (e.g. PTR records). Unique indicates that the 131 * record's name is to be unique on the network (e.g. SRV records). 132 */ 133 134 kDNSServiceFlagsBrowseDomains = 0x40, 135 kDNSServiceFlagsRegistrationDomains = 0x80, 136 /* Flags for specifying domain enumeration type in DNSServiceEnumerateDomains. 137 * BrowseDomains enumerates domains recommended for browsing, RegistrationDomains 138 * enumerates domains recommended for registration. 139 */ 140 141 kDNSServiceFlagsLongLivedQuery = 0x100, 142 /* Flag for creating a long-lived unicast query for the DNSServiceQueryRecord call. */ 143 144 kDNSServiceFlagsAllowRemoteQuery = 0x200, 145 /* Flag for creating a record for which we will answer remote queries 146 * (queries from hosts more than one hop away; hosts not directly connected to the local link). 147 */ 148 149 kDNSServiceFlagsForceMulticast = 0x400, 150 /* Flag for signifying that a query or registration should be performed exclusively via multicast DNS, 151 * even for a name in a domain (e.g. foo.apple.com.) that would normally imply unicast DNS. 152 */ 153 154 kDNSServiceFlagsReturnCNAME = 0x800 155 /* Flag for returning CNAME records in the DNSServiceQueryRecord call. CNAME records are 156 * normally followed without indicating to the client that there was a CNAME record. 157 */ 158 }; 159 160 /* 161 * The values for DNS Classes and Types are listed in RFC 1035, and are available 162 * on every OS in its DNS header file. Unfortunately every OS does not have the 163 * same header file containing DNS Class and Type constants, and the names of 164 * the constants are not consistent. For example, BIND 8 uses "T_A", 165 * BIND 9 uses "ns_t_a", Windows uses "DNS_TYPE_A", etc. 166 * For this reason, these constants are also listed here, so that code using 167 * the DNS-SD programming APIs can use these constants, so that the same code 168 * can compile on all our supported platforms. 169 */ 170 171 enum 172 { 173 kDNSServiceClass_IN = 1 /* Internet */ 174 }; 175 176 enum 177 { 178 kDNSServiceType_A = 1, /* Host address. */ 179 kDNSServiceType_NS = 2, /* Authoritative server. */ 180 kDNSServiceType_MD = 3, /* Mail destination. */ 181 kDNSServiceType_MF = 4, /* Mail forwarder. */ 182 kDNSServiceType_CNAME = 5, /* Canonical name. */ 183 kDNSServiceType_SOA = 6, /* Start of authority zone. */ 184 kDNSServiceType_MB = 7, /* Mailbox domain name. */ 185 kDNSServiceType_MG = 8, /* Mail group member. */ 186 kDNSServiceType_MR = 9, /* Mail rename name. */ 187 kDNSServiceType_NULL = 10, /* Null resource record. */ 188 kDNSServiceType_WKS = 11, /* Well known service. */ 189 kDNSServiceType_PTR = 12, /* Domain name pointer. */ 190 kDNSServiceType_HINFO = 13, /* Host information. */ 191 kDNSServiceType_MINFO = 14, /* Mailbox information. */ 192 kDNSServiceType_MX = 15, /* Mail routing information. */ 193 kDNSServiceType_TXT = 16, /* One or more text strings. */ 194 kDNSServiceType_RP = 17, /* Responsible person. */ 195 kDNSServiceType_AFSDB = 18, /* AFS cell database. */ 196 kDNSServiceType_X25 = 19, /* X_25 calling address. */ 197 kDNSServiceType_ISDN = 20, /* ISDN calling address. */ 198 kDNSServiceType_RT = 21, /* Router. */ 199 kDNSServiceType_NSAP = 22, /* NSAP address. */ 200 kDNSServiceType_NSAP_PTR = 23, /* Reverse NSAP lookup (deprecated). */ 201 kDNSServiceType_SIG = 24, /* Security signature. */ 202 kDNSServiceType_KEY = 25, /* Security key. */ 203 kDNSServiceType_PX = 26, /* X.400 mail mapping. */ 204 kDNSServiceType_GPOS = 27, /* Geographical position (withdrawn). */ 205 kDNSServiceType_AAAA = 28, /* IPv6 Address. */ 206 kDNSServiceType_LOC = 29, /* Location Information. */ 207 kDNSServiceType_NXT = 30, /* Next domain (security). */ 208 kDNSServiceType_EID = 31, /* Endpoint identifier. */ 209 kDNSServiceType_NIMLOC = 32, /* Nimrod Locator. */ 210 kDNSServiceType_SRV = 33, /* Server Selection. */ 211 kDNSServiceType_ATMA = 34, /* ATM Address */ 212 kDNSServiceType_NAPTR = 35, /* Naming Authority PoinTeR */ 213 kDNSServiceType_KX = 36, /* Key Exchange */ 214 kDNSServiceType_CERT = 37, /* Certification record */ 215 kDNSServiceType_A6 = 38, /* IPv6 Address (deprecated) */ 216 kDNSServiceType_DNAME = 39, /* Non-terminal DNAME (for IPv6) */ 217 kDNSServiceType_SINK = 40, /* Kitchen sink (experimentatl) */ 218 kDNSServiceType_OPT = 41, /* EDNS0 option (meta-RR) */ 219 kDNSServiceType_TKEY = 249, /* Transaction key */ 220 kDNSServiceType_TSIG = 250, /* Transaction signature. */ 221 kDNSServiceType_IXFR = 251, /* Incremental zone transfer. */ 222 kDNSServiceType_AXFR = 252, /* Transfer zone of authority. */ 223 kDNSServiceType_MAILB = 253, /* Transfer mailbox records. */ 224 kDNSServiceType_MAILA = 254, /* Transfer mail agent records. */ 225 kDNSServiceType_ANY = 255 /* Wildcard match. */ 226 }; 227 228 229 /* possible error code values */ 230 enum 231 { 232 kDNSServiceErr_NoError = 0, 233 kDNSServiceErr_Unknown = -65537, /* 0xFFFE FFFF */ 234 kDNSServiceErr_NoSuchName = -65538, 235 kDNSServiceErr_NoMemory = -65539, 236 kDNSServiceErr_BadParam = -65540, 237 kDNSServiceErr_BadReference = -65541, 238 kDNSServiceErr_BadState = -65542, 239 kDNSServiceErr_BadFlags = -65543, 240 kDNSServiceErr_Unsupported = -65544, 241 kDNSServiceErr_NotInitialized = -65545, 242 kDNSServiceErr_AlreadyRegistered = -65547, 243 kDNSServiceErr_NameConflict = -65548, 244 kDNSServiceErr_Invalid = -65549, 245 kDNSServiceErr_Firewall = -65550, 246 kDNSServiceErr_Incompatible = -65551, /* client library incompatible with daemon */ 247 kDNSServiceErr_BadInterfaceIndex = -65552, 248 kDNSServiceErr_Refused = -65553, 249 kDNSServiceErr_NoSuchRecord = -65554, 250 kDNSServiceErr_NoAuth = -65555, 251 kDNSServiceErr_NoSuchKey = -65556, 252 kDNSServiceErr_NATTraversal = -65557, 253 kDNSServiceErr_DoubleNAT = -65558, 254 kDNSServiceErr_BadTime = -65559 255 /* mDNS Error codes are in the range 256 * FFFE FF00 (-65792) to FFFE FFFF (-65537) */ 257 }; 258 259 260 /* Maximum length, in bytes, of a service name represented as a */ 261 /* literal C-String, including the terminating NULL at the end. */ 262 263 #define kDNSServiceMaxServiceName 64 264 265 /* Maximum length, in bytes, of a domain name represented as an *escaped* C-String */ 266 /* including the final trailing dot, and the C-String terminating NULL at the end. */ 267 268 #define kDNSServiceMaxDomainName 1005 269 270 /* 271 * Notes on DNS Name Escaping 272 * -- or -- 273 * "Why is kDNSServiceMaxDomainName 1005, when the maximum legal domain name is 255 bytes?" 274 * 275 * All strings used in DNS-SD are UTF-8 strings. 276 * With few exceptions, most are also escaped using standard DNS escaping rules: 277 * 278 * '\\' represents a single literal '\' in the name 279 * '\.' represents a single literal '.' in the name 280 * '\ddd', where ddd is a three-digit decimal value from 000 to 255, 281 * represents a single literal byte with that value. 282 * A bare unescaped '.' is a label separator, marking a boundary between domain and subdomain. 283 * 284 * The exceptions, that do not use escaping, are the routines where the full 285 * DNS name of a resource is broken, for convenience, into servicename/regtype/domain. 286 * In these routines, the "servicename" is NOT escaped. It does not need to be, since 287 * it is, by definition, just a single literal string. Any characters in that string 288 * represent exactly what they are. The "regtype" portion is, technically speaking, 289 * escaped, but since legal regtypes are only allowed to contain letters, digits, 290 * and hyphens, there is nothing to escape, so the issue is moot. The "domain" 291 * portion is also escaped, though most domains in use on the public Internet 292 * today, like regtypes, don't contain any characters that need to be escaped. 293 * As DNS-SD becomes more popular, rich-text domains for service discovery will 294 * become common, so software should be written to cope with domains with escaping. 295 * 296 * The servicename may be up to 63 bytes of UTF-8 text (not counting the C-String 297 * terminating NULL at the end). The regtype is of the form _service._tcp or 298 * _service._udp, where the "service" part is 1-14 characters, which may be 299 * letters, digits, or hyphens. The domain part of the three-part name may be 300 * any legal domain, providing that the resulting servicename+regtype+domain 301 * name does not exceed 255 bytes. 302 * 303 * For most software, these issues are transparent. When browsing, the discovered 304 * servicenames should simply be displayed as-is. When resolving, the discovered 305 * servicename/regtype/domain are simply passed unchanged to DNSServiceResolve(). 306 * When a DNSServiceResolve() succeeds, the returned fullname is already in 307 * the correct format to pass to standard system DNS APIs such as res_query(). 308 * For converting from servicename/regtype/domain to a single properly-escaped 309 * full DNS name, the helper function DNSServiceConstructFullName() is provided. 310 * 311 * The following (highly contrived) example illustrates the escaping process. 312 * Suppose you have an service called "Dr. Smith\Dr. Johnson", of type "_ftp._tcp" 313 * in subdomain "4th. Floor" of subdomain "Building 2" of domain "apple.com." 314 * The full (escaped) DNS name of this service's SRV record would be: 315 * Dr\.\032Smith\\Dr\.\032Johnson._ftp._tcp.4th\.\032Floor.Building\0322.apple.com. 316 */ 317 318 319 /* 320 * Constants for specifying an interface index 321 * 322 * Specific interface indexes are identified via a 32-bit unsigned integer returned 323 * by the if_nametoindex() family of calls. 324 * 325 * If the client passes 0 for interface index, that means "do the right thing", 326 * which (at present) means, "if the name is in an mDNS local multicast domain 327 * (e.g. 'local.', '254.169.in-addr.arpa.', '{8,9,A,B}.E.F.ip6.arpa.') then multicast 328 * on all applicable interfaces, otherwise send via unicast to the appropriate 329 * DNS server." Normally, most clients will use 0 for interface index to 330 * automatically get the default sensible behaviour. 331 * 332 * If the client passes a positive interface index, then for multicast names that 333 * indicates to do the operation only on that one interface. For unicast names the 334 * interface index is ignored unless kDNSServiceFlagsForceMulticast is also set. 335 * 336 * If the client passes kDNSServiceInterfaceIndexLocalOnly when registering 337 * a service, then that service will be found *only* by other local clients 338 * on the same machine that are browsing using kDNSServiceInterfaceIndexLocalOnly 339 * or kDNSServiceInterfaceIndexAny. 340 * If a client has a 'private' service, accessible only to other processes 341 * running on the same machine, this allows the client to advertise that service 342 * in a way such that it does not inadvertently appear in service lists on 343 * all the other machines on the network. 344 * 345 * If the client passes kDNSServiceInterfaceIndexLocalOnly when browsing 346 * then it will find *all* records registered on that same local machine. 347 * Clients explicitly wishing to discover *only* LocalOnly services can 348 * accomplish this by inspecting the interfaceIndex of each service reported 349 * to their DNSServiceBrowseReply() callback function, and discarding those 350 * where the interface index is not kDNSServiceInterfaceIndexLocalOnly. 351 */ 352 353 #define kDNSServiceInterfaceIndexAny 0 354 #define kDNSServiceInterfaceIndexLocalOnly ( (uint32_t) -1 ) 355 356 357 typedef uint32_t DNSServiceFlags; 358 typedef int32_t DNSServiceErrorType; 359 360 361 /********************************************************************************************* 362 * 363 * Unix Domain Socket access, DNSServiceRef deallocation, and data processing functions 364 * 365 *********************************************************************************************/ 366 367 368 /* DNSServiceRefSockFD() 369 * 370 * Access underlying Unix domain socket for an initialized DNSServiceRef. 371 * The DNS Service Discovery implmementation uses this socket to communicate between 372 * the client and the mDNSResponder daemon. The application MUST NOT directly read from 373 * or write to this socket. Access to the socket is provided so that it can be used as a 374 * run loop source, or in a select() loop: when data is available for reading on the socket, 375 * DNSServiceProcessResult() should be called, which will extract the daemon's reply from 376 * the socket, and pass it to the appropriate application callback. By using a run loop or 377 * select(), results from the daemon can be processed asynchronously. Without using these 378 * constructs, DNSServiceProcessResult() will block until the response from the daemon arrives. 379 * The client is responsible for ensuring that the data on the socket is processed in a timely 380 * fashion - the daemon may terminate its connection with a client that does not clear its 381 * socket buffer. 382 * 383 * sdRef: A DNSServiceRef initialized by any of the DNSService calls. 384 * 385 * return value: The DNSServiceRef's underlying socket descriptor, or -1 on 386 * error. 387 */ 388 389 int DNSSD_API DNSServiceRefSockFD(DNSServiceRef sdRef); 390 391 392 /* DNSServiceProcessResult() 393 * 394 * Read a reply from the daemon, calling the appropriate application callback. This call will 395 * block until the daemon's response is received. Use DNSServiceRefSockFD() in 396 * conjunction with a run loop or select() to determine the presence of a response from the 397 * server before calling this function to process the reply without blocking. Call this function 398 * at any point if it is acceptable to block until the daemon's response arrives. Note that the 399 * client is responsible for ensuring that DNSServiceProcessResult() is called whenever there is 400 * a reply from the daemon - the daemon may terminate its connection with a client that does not 401 * process the daemon's responses. 402 * 403 * sdRef: A DNSServiceRef initialized by any of the DNSService calls 404 * that take a callback parameter. 405 * 406 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns 407 * an error code indicating the specific failure that occurred. 408 */ 409 410 DNSServiceErrorType DNSSD_API DNSServiceProcessResult(DNSServiceRef sdRef); 411 412 413 /* DNSServiceRefDeallocate() 414 * 415 * Terminate a connection with the daemon and free memory associated with the DNSServiceRef. 416 * Any services or records registered with this DNSServiceRef will be deregistered. Any 417 * Browse, Resolve, or Query operations called with this reference will be terminated. 418 * 419 * Note: If the reference's underlying socket is used in a run loop or select() call, it should 420 * be removed BEFORE DNSServiceRefDeallocate() is called, as this function closes the reference's 421 * socket. 422 * 423 * Note: If the reference was initialized with DNSServiceCreateConnection(), any DNSRecordRefs 424 * created via this reference will be invalidated by this call - the resource records are 425 * deregistered, and their DNSRecordRefs may not be used in subsequent functions. Similarly, 426 * if the reference was initialized with DNSServiceRegister, and an extra resource record was 427 * added to the service via DNSServiceAddRecord(), the DNSRecordRef created by the Add() call 428 * is invalidated when this function is called - the DNSRecordRef may not be used in subsequent 429 * functions. 430 * 431 * Note: This call is to be used only with the DNSServiceRef defined by this API. It is 432 * not compatible with dns_service_discovery_ref objects defined in the legacy Mach-based 433 * DNSServiceDiscovery.h API. 434 * 435 * sdRef: A DNSServiceRef initialized by any of the DNSService calls. 436 * 437 */ 438 439 void DNSSD_API DNSServiceRefDeallocate(DNSServiceRef sdRef); 440 441 442 /********************************************************************************************* 443 * 444 * Domain Enumeration 445 * 446 *********************************************************************************************/ 447 448 /* DNSServiceEnumerateDomains() 449 * 450 * Asynchronously enumerate domains available for browsing and registration. 451 * 452 * The enumeration MUST be cancelled via DNSServiceRefDeallocate() when no more domains 453 * are to be found. 454 * 455 * Note that the names returned are (like all of DNS-SD) UTF-8 strings, 456 * and are escaped using standard DNS escaping rules. 457 * (See "Notes on DNS Name Escaping" earlier in this file for more details.) 458 * A graphical browser displaying a hierarchical tree-structured view should cut 459 * the names at the bare dots to yield individual labels, then de-escape each 460 * label according to the escaping rules, and then display the resulting UTF-8 text. 461 * 462 * DNSServiceDomainEnumReply Callback Parameters: 463 * 464 * sdRef: The DNSServiceRef initialized by DNSServiceEnumerateDomains(). 465 * 466 * flags: Possible values are: 467 * kDNSServiceFlagsMoreComing 468 * kDNSServiceFlagsAdd 469 * kDNSServiceFlagsDefault 470 * 471 * interfaceIndex: Specifies the interface on which the domain exists. (The index for a given 472 * interface is determined via the if_nametoindex() family of calls.) 473 * 474 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise indicates 475 * the failure that occurred (other parameters are undefined if errorCode is nonzero). 476 * 477 * replyDomain: The name of the domain. 478 * 479 * context: The context pointer passed to DNSServiceEnumerateDomains. 480 * 481 */ 482 483 typedef void (DNSSD_API *DNSServiceDomainEnumReply) 484 ( 485 DNSServiceRef sdRef, 486 DNSServiceFlags flags, 487 uint32_t interfaceIndex, 488 DNSServiceErrorType errorCode, 489 const char *replyDomain, 490 void *context 491 ); 492 493 494 /* DNSServiceEnumerateDomains() Parameters: 495 * 496 * 497 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 498 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 499 * and the enumeration operation will run indefinitely until the client 500 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 501 * 502 * flags: Possible values are: 503 * kDNSServiceFlagsBrowseDomains to enumerate domains recommended for browsing. 504 * kDNSServiceFlagsRegistrationDomains to enumerate domains recommended 505 * for registration. 506 * 507 * interfaceIndex: If non-zero, specifies the interface on which to look for domains. 508 * (the index for a given interface is determined via the if_nametoindex() 509 * family of calls.) Most applications will pass 0 to enumerate domains on 510 * all interfaces. See "Constants for specifying an interface index" for more details. 511 * 512 * callBack: The function to be called when a domain is found or the call asynchronously 513 * fails. 514 * 515 * context: An application context pointer which is passed to the callback function 516 * (may be NULL). 517 * 518 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 519 * errors are delivered to the callback), otherwise returns an error code indicating 520 * the error that occurred (the callback is not invoked and the DNSServiceRef 521 * is not initialized.) 522 */ 523 524 DNSServiceErrorType DNSSD_API DNSServiceEnumerateDomains 525 ( 526 DNSServiceRef *sdRef, 527 DNSServiceFlags flags, 528 uint32_t interfaceIndex, 529 DNSServiceDomainEnumReply callBack, 530 void *context /* may be NULL */ 531 ); 532 533 534 /********************************************************************************************* 535 * 536 * Service Registration 537 * 538 *********************************************************************************************/ 539 540 /* Register a service that is discovered via Browse() and Resolve() calls. 541 * 542 * 543 * DNSServiceRegisterReply() Callback Parameters: 544 * 545 * sdRef: The DNSServiceRef initialized by DNSServiceRegister(). 546 * 547 * flags: Currently unused, reserved for future use. 548 * 549 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 550 * indicate the failure that occurred (including name conflicts, 551 * if the kDNSServiceFlagsNoAutoRename flag was used when registering.) 552 * Other parameters are undefined if errorCode is nonzero. 553 * 554 * name: The service name registered (if the application did not specify a name in 555 * DNSServiceRegister(), this indicates what name was automatically chosen). 556 * 557 * regtype: The type of service registered, as it was passed to the callout. 558 * 559 * domain: The domain on which the service was registered (if the application did not 560 * specify a domain in DNSServiceRegister(), this indicates the default domain 561 * on which the service was registered). 562 * 563 * context: The context pointer that was passed to the callout. 564 * 565 */ 566 567 typedef void (DNSSD_API *DNSServiceRegisterReply) 568 ( 569 DNSServiceRef sdRef, 570 DNSServiceFlags flags, 571 DNSServiceErrorType errorCode, 572 const char *name, 573 const char *regtype, 574 const char *domain, 575 void *context 576 ); 577 578 579 /* DNSServiceRegister() Parameters: 580 * 581 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 582 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 583 * and the registration will remain active indefinitely until the client 584 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 585 * 586 * interfaceIndex: If non-zero, specifies the interface on which to register the service 587 * (the index for a given interface is determined via the if_nametoindex() 588 * family of calls.) Most applications will pass 0 to register on all 589 * available interfaces. See "Constants for specifying an interface index" for more details. 590 * 591 * flags: Indicates the renaming behavior on name conflict (most applications 592 * will pass 0). See flag definitions above for details. 593 * 594 * name: If non-NULL, specifies the service name to be registered. 595 * Most applications will not specify a name, in which case the computer 596 * name is used (this name is communicated to the client via the callback). 597 * If a name is specified, it must be 1-63 bytes of UTF-8 text. 598 * If the name is longer than 63 bytes it will be automatically truncated 599 * to a legal length, unless the NoAutoRename flag is set, 600 * in which case kDNSServiceErr_BadParam will be returned. 601 * 602 * regtype: The service type followed by the protocol, separated by a dot 603 * (e.g. "_ftp._tcp"). The service type must be an underscore, followed 604 * by 1-14 characters, which may be letters, digits, or hyphens. 605 * The transport protocol must be "_tcp" or "_udp". New service types 606 * should be registered at <http://www.dns-sd.org/ServiceTypes.html>. 607 * 608 * domain: If non-NULL, specifies the domain on which to advertise the service. 609 * Most applications will not specify a domain, instead automatically 610 * registering in the default domain(s). 611 * 612 * host: If non-NULL, specifies the SRV target host name. Most applications 613 * will not specify a host, instead automatically using the machine's 614 * default host name(s). Note that specifying a non-NULL host does NOT 615 * create an address record for that host - the application is responsible 616 * for ensuring that the appropriate address record exists, or creating it 617 * via DNSServiceRegisterRecord(). 618 * 619 * port: The port, in network byte order, on which the service accepts connections. 620 * Pass 0 for a "placeholder" service (i.e. a service that will not be discovered 621 * by browsing, but will cause a name conflict if another client tries to 622 * register that same name). Most clients will not use placeholder services. 623 * 624 * txtLen: The length of the txtRecord, in bytes. Must be zero if the txtRecord is NULL. 625 * 626 * txtRecord: The TXT record rdata. A non-NULL txtRecord MUST be a properly formatted DNS 627 * TXT record, i.e. <length byte> <data> <length byte> <data> ... 628 * Passing NULL for the txtRecord is allowed as a synonym for txtLen=1, txtRecord="", 629 * i.e. it creates a TXT record of length one containing a single empty string. 630 * RFC 1035 doesn't allow a TXT record to contain *zero* strings, so a single empty 631 * string is the smallest legal DNS TXT record. 632 * As with the other parameters, the DNSServiceRegister call copies the txtRecord 633 * data; e.g. if you allocated the storage for the txtRecord parameter with malloc() 634 * then you can safely free that memory right after the DNSServiceRegister call returns. 635 * 636 * callBack: The function to be called when the registration completes or asynchronously 637 * fails. The client MAY pass NULL for the callback - The client will NOT be notified 638 * of the default values picked on its behalf, and the client will NOT be notified of any 639 * asynchronous errors (e.g. out of memory errors, etc.) that may prevent the registration 640 * of the service. The client may NOT pass the NoAutoRename flag if the callback is NULL. 641 * The client may still deregister the service at any time via DNSServiceRefDeallocate(). 642 * 643 * context: An application context pointer which is passed to the callback function 644 * (may be NULL). 645 * 646 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 647 * errors are delivered to the callback), otherwise returns an error code indicating 648 * the error that occurred (the callback is never invoked and the DNSServiceRef 649 * is not initialized.) 650 */ 651 652 DNSServiceErrorType DNSSD_API DNSServiceRegister 653 ( 654 DNSServiceRef *sdRef, 655 DNSServiceFlags flags, 656 uint32_t interfaceIndex, 657 const char *name, /* may be NULL */ 658 const char *regtype, 659 const char *domain, /* may be NULL */ 660 const char *host, /* may be NULL */ 661 uint16_t port, 662 uint16_t txtLen, 663 const void *txtRecord, /* may be NULL */ 664 DNSServiceRegisterReply callBack, /* may be NULL */ 665 void *context /* may be NULL */ 666 ); 667 668 669 /* DNSServiceAddRecord() 670 * 671 * Add a record to a registered service. The name of the record will be the same as the 672 * registered service's name. 673 * The record can later be updated or deregistered by passing the RecordRef initialized 674 * by this function to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 675 * 676 * Note that the DNSServiceAddRecord/UpdateRecord/RemoveRecord are *NOT* thread-safe 677 * with respect to a single DNSServiceRef. If you plan to have multiple threads 678 * in your program simultaneously add, update, or remove records from the same 679 * DNSServiceRef, then it's the caller's responsibility to use a mutext lock 680 * or take similar appropriate precautions to serialize those calls. 681 * 682 * 683 * Parameters; 684 * 685 * sdRef: A DNSServiceRef initialized by DNSServiceRegister(). 686 * 687 * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this 688 * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 689 * If the above DNSServiceRef is passed to DNSServiceRefDeallocate(), RecordRef is also 690 * invalidated and may not be used further. 691 * 692 * flags: Currently ignored, reserved for future use. 693 * 694 * rrtype: The type of the record (e.g. kDNSServiceType_TXT, kDNSServiceType_SRV, etc) 695 * 696 * rdlen: The length, in bytes, of the rdata. 697 * 698 * rdata: The raw rdata to be contained in the added resource record. 699 * 700 * ttl: The time to live of the resource record, in seconds. Pass 0 to use a default value. 701 * 702 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 703 * error code indicating the error that occurred (the RecordRef is not initialized). 704 */ 705 706 DNSServiceErrorType DNSSD_API DNSServiceAddRecord 707 ( 708 DNSServiceRef sdRef, 709 DNSRecordRef *RecordRef, 710 DNSServiceFlags flags, 711 uint16_t rrtype, 712 uint16_t rdlen, 713 const void *rdata, 714 uint32_t ttl 715 ); 716 717 718 /* DNSServiceUpdateRecord 719 * 720 * Update a registered resource record. The record must either be: 721 * - The primary txt record of a service registered via DNSServiceRegister() 722 * - A record added to a registered service via DNSServiceAddRecord() 723 * - An individual record registered by DNSServiceRegisterRecord() 724 * 725 * 726 * Parameters: 727 * 728 * sdRef: A DNSServiceRef that was initialized by DNSServiceRegister() 729 * or DNSServiceCreateConnection(). 730 * 731 * RecordRef: A DNSRecordRef initialized by DNSServiceAddRecord, or NULL to update the 732 * service's primary txt record. 733 * 734 * flags: Currently ignored, reserved for future use. 735 * 736 * rdlen: The length, in bytes, of the new rdata. 737 * 738 * rdata: The new rdata to be contained in the updated resource record. 739 * 740 * ttl: The time to live of the updated resource record, in seconds. 741 * 742 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 743 * error code indicating the error that occurred. 744 */ 745 746 DNSServiceErrorType DNSSD_API DNSServiceUpdateRecord 747 ( 748 DNSServiceRef sdRef, 749 DNSRecordRef RecordRef, /* may be NULL */ 750 DNSServiceFlags flags, 751 uint16_t rdlen, 752 const void *rdata, 753 uint32_t ttl 754 ); 755 756 757 /* DNSServiceRemoveRecord 758 * 759 * Remove a record previously added to a service record set via DNSServiceAddRecord(), or deregister 760 * an record registered individually via DNSServiceRegisterRecord(). 761 * 762 * Parameters: 763 * 764 * sdRef: A DNSServiceRef initialized by DNSServiceRegister() (if the 765 * record being removed was registered via DNSServiceAddRecord()) or by 766 * DNSServiceCreateConnection() (if the record being removed was registered via 767 * DNSServiceRegisterRecord()). 768 * 769 * recordRef: A DNSRecordRef initialized by a successful call to DNSServiceAddRecord() 770 * or DNSServiceRegisterRecord(). 771 * 772 * flags: Currently ignored, reserved for future use. 773 * 774 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 775 * error code indicating the error that occurred. 776 */ 777 778 DNSServiceErrorType DNSSD_API DNSServiceRemoveRecord 779 ( 780 DNSServiceRef sdRef, 781 DNSRecordRef RecordRef, 782 DNSServiceFlags flags 783 ); 784 785 786 /********************************************************************************************* 787 * 788 * Service Discovery 789 * 790 *********************************************************************************************/ 791 792 /* Browse for instances of a service. 793 * 794 * 795 * DNSServiceBrowseReply() Parameters: 796 * 797 * sdRef: The DNSServiceRef initialized by DNSServiceBrowse(). 798 * 799 * flags: Possible values are kDNSServiceFlagsMoreComing and kDNSServiceFlagsAdd. 800 * See flag definitions for details. 801 * 802 * interfaceIndex: The interface on which the service is advertised. This index should 803 * be passed to DNSServiceResolve() when resolving the service. 804 * 805 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will 806 * indicate the failure that occurred. Other parameters are undefined if 807 * the errorCode is nonzero. 808 * 809 * serviceName: The discovered service name. This name should be displayed to the user, 810 * and stored for subsequent use in the DNSServiceResolve() call. 811 * 812 * regtype: The service type, which is usually (but not always) the same as was passed 813 * to DNSServiceBrowse(). One case where the discovered service type may 814 * not be the same as the requested service type is when using subtypes: 815 * The client may want to browse for only those ftp servers that allow 816 * anonymous connections. The client will pass the string "_ftp._tcp,_anon" 817 * to DNSServiceBrowse(), but the type of the service that's discovered 818 * is simply "_ftp._tcp". The regtype for each discovered service instance 819 * should be stored along with the name, so that it can be passed to 820 * DNSServiceResolve() when the service is later resolved. 821 * 822 * domain: The domain of the discovered service instance. This may or may not be the 823 * same as the domain that was passed to DNSServiceBrowse(). The domain for each 824 * discovered service instance should be stored along with the name, so that 825 * it can be passed to DNSServiceResolve() when the service is later resolved. 826 * 827 * context: The context pointer that was passed to the callout. 828 * 829 */ 830 831 typedef void (DNSSD_API *DNSServiceBrowseReply) 832 ( 833 DNSServiceRef sdRef, 834 DNSServiceFlags flags, 835 uint32_t interfaceIndex, 836 DNSServiceErrorType errorCode, 837 const char *serviceName, 838 const char *regtype, 839 const char *replyDomain, 840 void *context 841 ); 842 843 844 /* DNSServiceBrowse() Parameters: 845 * 846 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 847 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 848 * and the browse operation will run indefinitely until the client 849 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 850 * 851 * flags: Currently ignored, reserved for future use. 852 * 853 * interfaceIndex: If non-zero, specifies the interface on which to browse for services 854 * (the index for a given interface is determined via the if_nametoindex() 855 * family of calls.) Most applications will pass 0 to browse on all available 856 * interfaces. See "Constants for specifying an interface index" for more details. 857 * 858 * regtype: The service type being browsed for followed by the protocol, separated by a 859 * dot (e.g. "_ftp._tcp"). The transport protocol must be "_tcp" or "_udp". 860 * 861 * domain: If non-NULL, specifies the domain on which to browse for services. 862 * Most applications will not specify a domain, instead browsing on the 863 * default domain(s). 864 * 865 * callBack: The function to be called when an instance of the service being browsed for 866 * is found, or if the call asynchronously fails. 867 * 868 * context: An application context pointer which is passed to the callback function 869 * (may be NULL). 870 * 871 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 872 * errors are delivered to the callback), otherwise returns an error code indicating 873 * the error that occurred (the callback is not invoked and the DNSServiceRef 874 * is not initialized.) 875 */ 876 877 DNSServiceErrorType DNSSD_API DNSServiceBrowse 878 ( 879 DNSServiceRef *sdRef, 880 DNSServiceFlags flags, 881 uint32_t interfaceIndex, 882 const char *regtype, 883 const char *domain, /* may be NULL */ 884 DNSServiceBrowseReply callBack, 885 void *context /* may be NULL */ 886 ); 887 888 889 /* DNSServiceResolve() 890 * 891 * Resolve a service name discovered via DNSServiceBrowse() to a target host name, port number, and 892 * txt record. 893 * 894 * Note: Applications should NOT use DNSServiceResolve() solely for txt record monitoring - use 895 * DNSServiceQueryRecord() instead, as it is more efficient for this task. 896 * 897 * Note: When the desired results have been returned, the client MUST terminate the resolve by calling 898 * DNSServiceRefDeallocate(). 899 * 900 * Note: DNSServiceResolve() behaves correctly for typical services that have a single SRV record 901 * and a single TXT record. To resolve non-standard services with multiple SRV or TXT records, 902 * DNSServiceQueryRecord() should be used. 903 * 904 * DNSServiceResolveReply Callback Parameters: 905 * 906 * sdRef: The DNSServiceRef initialized by DNSServiceResolve(). 907 * 908 * flags: Currently unused, reserved for future use. 909 * 910 * interfaceIndex: The interface on which the service was resolved. 911 * 912 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will 913 * indicate the failure that occurred. Other parameters are undefined if 914 * the errorCode is nonzero. 915 * 916 * fullname: The full service domain name, in the form <servicename>.<protocol>.<domain>. 917 * (This name is escaped following standard DNS rules, making it suitable for 918 * passing to standard system DNS APIs such as res_query(), or to the 919 * special-purpose functions included in this API that take fullname parameters. 920 * See "Notes on DNS Name Escaping" earlier in this file for more details.) 921 * 922 * hosttarget: The target hostname of the machine providing the service. This name can 923 * be passed to functions like gethostbyname() to identify the host's IP address. 924 * 925 * port: The port, in network byte order, on which connections are accepted for this service. 926 * 927 * txtLen: The length of the txt record, in bytes. 928 * 929 * txtRecord: The service's primary txt record, in standard txt record format. 930 * 931 * context: The context pointer that was passed to the callout. 932 * 933 * NOTE: In earlier versions of this header file, the txtRecord parameter was declared "const char *" 934 * This is incorrect, since it contains length bytes which are values in the range 0 to 255, not -128 to +127. 935 * Depending on your compiler settings, this change may cause signed/unsigned mismatch warnings. 936 * These should be fixed by updating your own callback function definition to match the corrected 937 * function signature using "const unsigned char *txtRecord". Making this change may also fix inadvertent 938 * bugs in your callback function, where it could have incorrectly interpreted a length byte with value 250 939 * as being -6 instead, with various bad consequences ranging from incorrect operation to software crashes. 940 * If you need to maintain portable code that will compile cleanly with both the old and new versions of 941 * this header file, you should update your callback function definition to use the correct unsigned value, 942 * and then in the place where you pass your callback function to DNSServiceResolve(), use a cast to eliminate 943 * the compiler warning, e.g.: 944 * DNSServiceResolve(sd, flags, index, name, regtype, domain, (DNSServiceResolveReply)MyCallback, context); 945 * This will ensure that your code compiles cleanly without warnings (and more importantly, works correctly) 946 * with both the old header and with the new corrected version. 947 * 948 */ 949 950 typedef void (DNSSD_API *DNSServiceResolveReply) 951 ( 952 DNSServiceRef sdRef, 953 DNSServiceFlags flags, 954 uint32_t interfaceIndex, 955 DNSServiceErrorType errorCode, 956 const char *fullname, 957 const char *hosttarget, 958 uint16_t port, 959 uint16_t txtLen, 960 const unsigned char *txtRecord, 961 void *context 962 ); 963 964 965 /* DNSServiceResolve() Parameters 966 * 967 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 968 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 969 * and the resolve operation will run indefinitely until the client 970 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 971 * 972 * flags: Currently ignored, reserved for future use. 973 * 974 * interfaceIndex: The interface on which to resolve the service. If this resolve call is 975 * as a result of a currently active DNSServiceBrowse() operation, then the 976 * interfaceIndex should be the index reported in the DNSServiceBrowseReply 977 * callback. If this resolve call is using information previously saved 978 * (e.g. in a preference file) for later use, then use interfaceIndex 0, because 979 * the desired service may now be reachable via a different physical interface. 980 * See "Constants for specifying an interface index" for more details. 981 * 982 * name: The name of the service instance to be resolved, as reported to the 983 * DNSServiceBrowseReply() callback. 984 * 985 * regtype: The type of the service instance to be resolved, as reported to the 986 * DNSServiceBrowseReply() callback. 987 * 988 * domain: The domain of the service instance to be resolved, as reported to the 989 * DNSServiceBrowseReply() callback. 990 * 991 * callBack: The function to be called when a result is found, or if the call 992 * asynchronously fails. 993 * 994 * context: An application context pointer which is passed to the callback function 995 * (may be NULL). 996 * 997 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 998 * errors are delivered to the callback), otherwise returns an error code indicating 999 * the error that occurred (the callback is never invoked and the DNSServiceRef 1000 * is not initialized.) 1001 */ 1002 1003 DNSServiceErrorType DNSSD_API DNSServiceResolve 1004 ( 1005 DNSServiceRef *sdRef, 1006 DNSServiceFlags flags, 1007 uint32_t interfaceIndex, 1008 const char *name, 1009 const char *regtype, 1010 const char *domain, 1011 DNSServiceResolveReply callBack, 1012 void *context /* may be NULL */ 1013 ); 1014 1015 1016 /********************************************************************************************* 1017 * 1018 * Special Purpose Calls (most applications will not use these) 1019 * 1020 *********************************************************************************************/ 1021 1022 /* DNSServiceCreateConnection() 1023 * 1024 * Create a connection to the daemon allowing efficient registration of 1025 * multiple individual records. 1026 * 1027 * 1028 * Parameters: 1029 * 1030 * sdRef: A pointer to an uninitialized DNSServiceRef. Deallocating 1031 * the reference (via DNSServiceRefDeallocate()) severs the 1032 * connection and deregisters all records registered on this connection. 1033 * 1034 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns 1035 * an error code indicating the specific failure that occurred (in which 1036 * case the DNSServiceRef is not initialized). 1037 */ 1038 1039 DNSServiceErrorType DNSSD_API DNSServiceCreateConnection(DNSServiceRef *sdRef); 1040 1041 1042 /* DNSServiceRegisterRecord 1043 * 1044 * Register an individual resource record on a connected DNSServiceRef. 1045 * 1046 * Note that name conflicts occurring for records registered via this call must be handled 1047 * by the client in the callback. 1048 * 1049 * 1050 * DNSServiceRegisterRecordReply() parameters: 1051 * 1052 * sdRef: The connected DNSServiceRef initialized by 1053 * DNSServiceCreateConnection(). 1054 * 1055 * RecordRef: The DNSRecordRef initialized by DNSServiceRegisterRecord(). If the above 1056 * DNSServiceRef is passed to DNSServiceRefDeallocate(), this DNSRecordRef is 1057 * invalidated, and may not be used further. 1058 * 1059 * flags: Currently unused, reserved for future use. 1060 * 1061 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1062 * indicate the failure that occurred (including name conflicts.) 1063 * Other parameters are undefined if errorCode is nonzero. 1064 * 1065 * context: The context pointer that was passed to the callout. 1066 * 1067 */ 1068 1069 typedef void (DNSSD_API *DNSServiceRegisterRecordReply) 1070 ( 1071 DNSServiceRef sdRef, 1072 DNSRecordRef RecordRef, 1073 DNSServiceFlags flags, 1074 DNSServiceErrorType errorCode, 1075 void *context 1076 ); 1077 1078 1079 /* DNSServiceRegisterRecord() Parameters: 1080 * 1081 * sdRef: A DNSServiceRef initialized by DNSServiceCreateConnection(). 1082 * 1083 * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this 1084 * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 1085 * (To deregister ALL records registered on a single connected DNSServiceRef 1086 * and deallocate each of their corresponding DNSServiceRecordRefs, call 1087 * DNSServiceRefDealloocate()). 1088 * 1089 * flags: Possible values are kDNSServiceFlagsShared or kDNSServiceFlagsUnique 1090 * (see flag type definitions for details). 1091 * 1092 * interfaceIndex: If non-zero, specifies the interface on which to register the record 1093 * (the index for a given interface is determined via the if_nametoindex() 1094 * family of calls.) Passing 0 causes the record to be registered on all interfaces. 1095 * See "Constants for specifying an interface index" for more details. 1096 * 1097 * fullname: The full domain name of the resource record. 1098 * 1099 * rrtype: The numerical type of the resource record (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1100 * 1101 * rrclass: The class of the resource record (usually kDNSServiceClass_IN) 1102 * 1103 * rdlen: Length, in bytes, of the rdata. 1104 * 1105 * rdata: A pointer to the raw rdata, as it is to appear in the DNS record. 1106 * 1107 * ttl: The time to live of the resource record, in seconds. Pass 0 to use a default value. 1108 * 1109 * callBack: The function to be called when a result is found, or if the call 1110 * asynchronously fails (e.g. because of a name conflict.) 1111 * 1112 * context: An application context pointer which is passed to the callback function 1113 * (may be NULL). 1114 * 1115 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 1116 * errors are delivered to the callback), otherwise returns an error code indicating 1117 * the error that occurred (the callback is never invoked and the DNSRecordRef is 1118 * not initialized.) 1119 */ 1120 1121 DNSServiceErrorType DNSSD_API DNSServiceRegisterRecord 1122 ( 1123 DNSServiceRef sdRef, 1124 DNSRecordRef *RecordRef, 1125 DNSServiceFlags flags, 1126 uint32_t interfaceIndex, 1127 const char *fullname, 1128 uint16_t rrtype, 1129 uint16_t rrclass, 1130 uint16_t rdlen, 1131 const void *rdata, 1132 uint32_t ttl, 1133 DNSServiceRegisterRecordReply callBack, 1134 void *context /* may be NULL */ 1135 ); 1136 1137 1138 /* DNSServiceQueryRecord 1139 * 1140 * Query for an arbitrary DNS record. 1141 * 1142 * 1143 * DNSServiceQueryRecordReply() Callback Parameters: 1144 * 1145 * sdRef: The DNSServiceRef initialized by DNSServiceQueryRecord(). 1146 * 1147 * flags: Possible values are kDNSServiceFlagsMoreComing and 1148 * kDNSServiceFlagsAdd. The Add flag is NOT set for PTR records 1149 * with a ttl of 0, i.e. "Remove" events. 1150 * 1151 * interfaceIndex: The interface on which the query was resolved (the index for a given 1152 * interface is determined via the if_nametoindex() family of calls). 1153 * See "Constants for specifying an interface index" for more details. 1154 * 1155 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1156 * indicate the failure that occurred. Other parameters are undefined if 1157 * errorCode is nonzero. 1158 * 1159 * fullname: The resource record's full domain name. 1160 * 1161 * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1162 * 1163 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1164 * 1165 * rdlen: The length, in bytes, of the resource record rdata. 1166 * 1167 * rdata: The raw rdata of the resource record. 1168 * 1169 * ttl: The resource record's time to live, in seconds. 1170 * 1171 * context: The context pointer that was passed to the callout. 1172 * 1173 */ 1174 1175 typedef void (DNSSD_API *DNSServiceQueryRecordReply) 1176 ( 1177 DNSServiceRef DNSServiceRef, 1178 DNSServiceFlags flags, 1179 uint32_t interfaceIndex, 1180 DNSServiceErrorType errorCode, 1181 const char *fullname, 1182 uint16_t rrtype, 1183 uint16_t rrclass, 1184 uint16_t rdlen, 1185 const void *rdata, 1186 uint32_t ttl, 1187 void *context 1188 ); 1189 1190 1191 /* DNSServiceQueryRecord() Parameters: 1192 * 1193 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 1194 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 1195 * and the query operation will run indefinitely until the client 1196 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1197 * 1198 * flags: Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast 1199 * query in a non-local domain. Without setting this flag, unicast queries 1200 * will be one-shot - that is, only answers available at the time of the call 1201 * will be returned. By setting this flag, answers (including Add and Remove 1202 * events) that become available after the initial call is made will generate 1203 * callbacks. This flag has no effect on link-local multicast queries. 1204 * 1205 * interfaceIndex: If non-zero, specifies the interface on which to issue the query 1206 * (the index for a given interface is determined via the if_nametoindex() 1207 * family of calls.) Passing 0 causes the name to be queried for on all 1208 * interfaces. See "Constants for specifying an interface index" for more details. 1209 * 1210 * fullname: The full domain name of the resource record to be queried for. 1211 * 1212 * rrtype: The numerical type of the resource record to be queried for 1213 * (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1214 * 1215 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1216 * 1217 * callBack: The function to be called when a result is found, or if the call 1218 * asynchronously fails. 1219 * 1220 * context: An application context pointer which is passed to the callback function 1221 * (may be NULL). 1222 * 1223 * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous 1224 * errors are delivered to the callback), otherwise returns an error code indicating 1225 * the error that occurred (the callback is never invoked and the DNSServiceRef 1226 * is not initialized.) 1227 */ 1228 1229 DNSServiceErrorType DNSSD_API DNSServiceQueryRecord 1230 ( 1231 DNSServiceRef *sdRef, 1232 DNSServiceFlags flags, 1233 uint32_t interfaceIndex, 1234 const char *fullname, 1235 uint16_t rrtype, 1236 uint16_t rrclass, 1237 DNSServiceQueryRecordReply callBack, 1238 void *context /* may be NULL */ 1239 ); 1240 1241 1242 /* DNSServiceReconfirmRecord 1243 * 1244 * Instruct the daemon to verify the validity of a resource record that appears to 1245 * be out of date (e.g. because tcp connection to a service's target failed.) 1246 * Causes the record to be flushed from the daemon's cache (as well as all other 1247 * daemons' caches on the network) if the record is determined to be invalid. 1248 * 1249 * Parameters: 1250 * 1251 * flags: Currently unused, reserved for future use. 1252 * 1253 * interfaceIndex: If non-zero, specifies the interface of the record in question. 1254 * Passing 0 causes all instances of this record to be reconfirmed. 1255 * 1256 * fullname: The resource record's full domain name. 1257 * 1258 * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1259 * 1260 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1261 * 1262 * rdlen: The length, in bytes, of the resource record rdata. 1263 * 1264 * rdata: The raw rdata of the resource record. 1265 * 1266 */ 1267 1268 DNSServiceErrorType DNSSD_API DNSServiceReconfirmRecord 1269 ( 1270 DNSServiceFlags flags, 1271 uint32_t interfaceIndex, 1272 const char *fullname, 1273 uint16_t rrtype, 1274 uint16_t rrclass, 1275 uint16_t rdlen, 1276 const void *rdata 1277 ); 1278 1279 1280 /********************************************************************************************* 1281 * 1282 * General Utility Functions 1283 * 1284 *********************************************************************************************/ 1285 1286 /* DNSServiceConstructFullName() 1287 * 1288 * Concatenate a three-part domain name (as returned by the above callbacks) into a 1289 * properly-escaped full domain name. Note that callbacks in the above functions ALREADY ESCAPE 1290 * strings where necessary. 1291 * 1292 * Parameters: 1293 * 1294 * fullName: A pointer to a buffer that where the resulting full domain name is to be written. 1295 * The buffer must be kDNSServiceMaxDomainName (1005) bytes in length to 1296 * accommodate the longest legal domain name without buffer overrun. 1297 * 1298 * service: The service name - any dots or backslashes must NOT be escaped. 1299 * May be NULL (to construct a PTR record name, e.g. 1300 * "_ftp._tcp.apple.com."). 1301 * 1302 * regtype: The service type followed by the protocol, separated by a dot 1303 * (e.g. "_ftp._tcp"). 1304 * 1305 * domain: The domain name, e.g. "apple.com.". Literal dots or backslashes, 1306 * if any, must be escaped, e.g. "1st\. Floor.apple.com." 1307 * 1308 * return value: Returns 0 on success, -1 on error. 1309 * 1310 */ 1311 1312 int DNSSD_API DNSServiceConstructFullName 1313 ( 1314 char *fullName, 1315 const char *service, /* may be NULL */ 1316 const char *regtype, 1317 const char *domain 1318 ); 1319 1320 1321 /********************************************************************************************* 1322 * 1323 * TXT Record Construction Functions 1324 * 1325 *********************************************************************************************/ 1326 1327 /* 1328 * A typical calling sequence for TXT record construction is something like: 1329 * 1330 * Client allocates storage for TXTRecord data (e.g. declare buffer on the stack) 1331 * TXTRecordCreate(); 1332 * TXTRecordSetValue(); 1333 * TXTRecordSetValue(); 1334 * TXTRecordSetValue(); 1335 * ... 1336 * DNSServiceRegister( ... TXTRecordGetLength(), TXTRecordGetBytesPtr() ... ); 1337 * TXTRecordDeallocate(); 1338 * Explicitly deallocate storage for TXTRecord data (if not allocated on the stack) 1339 */ 1340 1341 1342 /* TXTRecordRef 1343 * 1344 * Opaque internal data type. 1345 * Note: Represents a DNS-SD TXT record. 1346 */ 1347 1348 typedef union _TXTRecordRef_t { char PrivateData[16]; char *ForceNaturalAlignment; } TXTRecordRef; 1349 1350 1351 /* TXTRecordCreate() 1352 * 1353 * Creates a new empty TXTRecordRef referencing the specified storage. 1354 * 1355 * If the buffer parameter is NULL, or the specified storage size is not 1356 * large enough to hold a key subsequently added using TXTRecordSetValue(), 1357 * then additional memory will be added as needed using malloc(). 1358 * 1359 * On some platforms, when memory is low, malloc() may fail. In this 1360 * case, TXTRecordSetValue() will return kDNSServiceErr_NoMemory, and this 1361 * error condition will need to be handled as appropriate by the caller. 1362 * 1363 * You can avoid the need to handle this error condition if you ensure 1364 * that the storage you initially provide is large enough to hold all 1365 * the key/value pairs that are to be added to the record. 1366 * The caller can precompute the exact length required for all of the 1367 * key/value pairs to be added, or simply provide a fixed-sized buffer 1368 * known in advance to be large enough. 1369 * A no-value (key-only) key requires (1 + key length) bytes. 1370 * A key with empty value requires (1 + key length + 1) bytes. 1371 * A key with non-empty value requires (1 + key length + 1 + value length). 1372 * For most applications, DNS-SD TXT records are generally 1373 * less than 100 bytes, so in most cases a simple fixed-sized 1374 * 256-byte buffer will be more than sufficient. 1375 * Recommended size limits for DNS-SD TXT Records are discussed in 1376 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> 1377 * 1378 * Note: When passing parameters to and from these TXT record APIs, 1379 * the key name does not include the '=' character. The '=' character 1380 * is the separator between the key and value in the on-the-wire 1381 * packet format; it is not part of either the key or the value. 1382 * 1383 * txtRecord: A pointer to an uninitialized TXTRecordRef. 1384 * 1385 * bufferLen: The size of the storage provided in the "buffer" parameter. 1386 * 1387 * buffer: Optional caller-supplied storage used to hold the TXTRecord data. 1388 * This storage must remain valid for as long as 1389 * the TXTRecordRef. 1390 */ 1391 1392 void DNSSD_API TXTRecordCreate 1393 ( 1394 TXTRecordRef *txtRecord, 1395 uint16_t bufferLen, 1396 void *buffer 1397 ); 1398 1399 1400 /* TXTRecordDeallocate() 1401 * 1402 * Releases any resources allocated in the course of preparing a TXT Record 1403 * using TXTRecordCreate()/TXTRecordSetValue()/TXTRecordRemoveValue(). 1404 * Ownership of the buffer provided in TXTRecordCreate() returns to the client. 1405 * 1406 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 1407 * 1408 */ 1409 1410 void DNSSD_API TXTRecordDeallocate 1411 ( 1412 TXTRecordRef *txtRecord 1413 ); 1414 1415 1416 /* TXTRecordSetValue() 1417 * 1418 * Adds a key (optionally with value) to a TXTRecordRef. If the "key" already 1419 * exists in the TXTRecordRef, then the current value will be replaced with 1420 * the new value. 1421 * Keys may exist in four states with respect to a given TXT record: 1422 * - Absent (key does not appear at all) 1423 * - Present with no value ("key" appears alone) 1424 * - Present with empty value ("key=" appears in TXT record) 1425 * - Present with non-empty value ("key=value" appears in TXT record) 1426 * For more details refer to "Data Syntax for DNS-SD TXT Records" in 1427 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> 1428 * 1429 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 1430 * 1431 * key: A null-terminated string which only contains printable ASCII 1432 * values (0x20-0x7E), excluding '=' (0x3D). Keys should be 1433 * 8 characters or less (not counting the terminating null). 1434 * 1435 * valueSize: The size of the value. 1436 * 1437 * value: Any binary value. For values that represent 1438 * textual data, UTF-8 is STRONGLY recommended. 1439 * For values that represent textual data, valueSize 1440 * should NOT include the terminating null (if any) 1441 * at the end of the string. 1442 * If NULL, then "key" will be added with no value. 1443 * If non-NULL but valueSize is zero, then "key=" will be 1444 * added with empty value. 1445 * 1446 * return value: Returns kDNSServiceErr_NoError on success. 1447 * Returns kDNSServiceErr_Invalid if the "key" string contains 1448 * illegal characters. 1449 * Returns kDNSServiceErr_NoMemory if adding this key would 1450 * exceed the available storage. 1451 */ 1452 1453 DNSServiceErrorType DNSSD_API TXTRecordSetValue 1454 ( 1455 TXTRecordRef *txtRecord, 1456 const char *key, 1457 uint8_t valueSize, /* may be zero */ 1458 const void *value /* may be NULL */ 1459 ); 1460 1461 1462 /* TXTRecordRemoveValue() 1463 * 1464 * Removes a key from a TXTRecordRef. The "key" must be an 1465 * ASCII string which exists in the TXTRecordRef. 1466 * 1467 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 1468 * 1469 * key: A key name which exists in the TXTRecordRef. 1470 * 1471 * return value: Returns kDNSServiceErr_NoError on success. 1472 * Returns kDNSServiceErr_NoSuchKey if the "key" does not 1473 * exist in the TXTRecordRef. 1474 */ 1475 1476 DNSServiceErrorType DNSSD_API TXTRecordRemoveValue 1477 ( 1478 TXTRecordRef *txtRecord, 1479 const char *key 1480 ); 1481 1482 1483 /* TXTRecordGetLength() 1484 * 1485 * Allows you to determine the length of the raw bytes within a TXTRecordRef. 1486 * 1487 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 1488 * 1489 * return value: Returns the size of the raw bytes inside a TXTRecordRef 1490 * which you can pass directly to DNSServiceRegister() or 1491 * to DNSServiceUpdateRecord(). 1492 * Returns 0 if the TXTRecordRef is empty. 1493 */ 1494 1495 uint16_t DNSSD_API TXTRecordGetLength 1496 ( 1497 const TXTRecordRef *txtRecord 1498 ); 1499 1500 1501 /* TXTRecordGetBytesPtr() 1502 * 1503 * Allows you to retrieve a pointer to the raw bytes within a TXTRecordRef. 1504 * 1505 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 1506 * 1507 * return value: Returns a pointer to the raw bytes inside the TXTRecordRef 1508 * which you can pass directly to DNSServiceRegister() or 1509 * to DNSServiceUpdateRecord(). 1510 */ 1511 1512 const void * DNSSD_API TXTRecordGetBytesPtr 1513 ( 1514 const TXTRecordRef *txtRecord 1515 ); 1516 1517 1518 /********************************************************************************************* 1519 * 1520 * TXT Record Parsing Functions 1521 * 1522 *********************************************************************************************/ 1523 1524 /* 1525 * A typical calling sequence for TXT record parsing is something like: 1526 * 1527 * Receive TXT record data in DNSServiceResolve() callback 1528 * if (TXTRecordContainsKey(txtLen, txtRecord, "key")) then do something 1529 * val1ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key1", &len1); 1530 * val2ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key2", &len2); 1531 * ... 1532 * bcopy(val1ptr, myval1, len1); 1533 * bcopy(val2ptr, myval2, len2); 1534 * ... 1535 * return; 1536 * 1537 * If you wish to retain the values after return from the DNSServiceResolve() 1538 * callback, then you need to copy the data to your own storage using bcopy() 1539 * or similar, as shown in the example above. 1540 * 1541 * If for some reason you need to parse a TXT record you built yourself 1542 * using the TXT record construction functions above, then you can do 1543 * that using TXTRecordGetLength and TXTRecordGetBytesPtr calls: 1544 * TXTRecordGetValue(TXTRecordGetLength(x), TXTRecordGetBytesPtr(x), key, &len); 1545 * 1546 * Most applications only fetch keys they know about from a TXT record and 1547 * ignore the rest. 1548 * However, some debugging tools wish to fetch and display all keys. 1549 * To do that, use the TXTRecordGetCount() and TXTRecordGetItemAtIndex() calls. 1550 */ 1551 1552 /* TXTRecordContainsKey() 1553 * 1554 * Allows you to determine if a given TXT Record contains a specified key. 1555 * 1556 * txtLen: The size of the received TXT Record. 1557 * 1558 * txtRecord: Pointer to the received TXT Record bytes. 1559 * 1560 * key: A null-terminated ASCII string containing the key name. 1561 * 1562 * return value: Returns 1 if the TXT Record contains the specified key. 1563 * Otherwise, it returns 0. 1564 */ 1565 1566 int DNSSD_API TXTRecordContainsKey 1567 ( 1568 uint16_t txtLen, 1569 const void *txtRecord, 1570 const char *key 1571 ); 1572 1573 1574 /* TXTRecordGetValuePtr() 1575 * 1576 * Allows you to retrieve the value for a given key from a TXT Record. 1577 * 1578 * txtLen: The size of the received TXT Record 1579 * 1580 * txtRecord: Pointer to the received TXT Record bytes. 1581 * 1582 * key: A null-terminated ASCII string containing the key name. 1583 * 1584 * valueLen: On output, will be set to the size of the "value" data. 1585 * 1586 * return value: Returns NULL if the key does not exist in this TXT record, 1587 * or exists with no value (to differentiate between 1588 * these two cases use TXTRecordContainsKey()). 1589 * Returns pointer to location within TXT Record bytes 1590 * if the key exists with empty or non-empty value. 1591 * For empty value, valueLen will be zero. 1592 * For non-empty value, valueLen will be length of value data. 1593 */ 1594 1595 const void * DNSSD_API TXTRecordGetValuePtr 1596 ( 1597 uint16_t txtLen, 1598 const void *txtRecord, 1599 const char *key, 1600 uint8_t *valueLen 1601 ); 1602 1603 1604 /* TXTRecordGetCount() 1605 * 1606 * Returns the number of keys stored in the TXT Record. The count 1607 * can be used with TXTRecordGetItemAtIndex() to iterate through the keys. 1608 * 1609 * txtLen: The size of the received TXT Record. 1610 * 1611 * txtRecord: Pointer to the received TXT Record bytes. 1612 * 1613 * return value: Returns the total number of keys in the TXT Record. 1614 * 1615 */ 1616 1617 uint16_t DNSSD_API TXTRecordGetCount 1618 ( 1619 uint16_t txtLen, 1620 const void *txtRecord 1621 ); 1622 1623 1624 /* TXTRecordGetItemAtIndex() 1625 * 1626 * Allows you to retrieve a key name and value pointer, given an index into 1627 * a TXT Record. Legal index values range from zero to TXTRecordGetCount()-1. 1628 * It's also possible to iterate through keys in a TXT record by simply 1629 * calling TXTRecordGetItemAtIndex() repeatedly, beginning with index zero 1630 * and increasing until TXTRecordGetItemAtIndex() returns kDNSServiceErr_Invalid. 1631 * 1632 * On return: 1633 * For keys with no value, *value is set to NULL and *valueLen is zero. 1634 * For keys with empty value, *value is non-NULL and *valueLen is zero. 1635 * For keys with non-empty value, *value is non-NULL and *valueLen is non-zero. 1636 * 1637 * txtLen: The size of the received TXT Record. 1638 * 1639 * txtRecord: Pointer to the received TXT Record bytes. 1640 * 1641 * index: An index into the TXT Record. 1642 * 1643 * keyBufLen: The size of the string buffer being supplied. 1644 * 1645 * key: A string buffer used to store the key name. 1646 * On return, the buffer contains a null-terminated C string 1647 * giving the key name. DNS-SD TXT keys are usually 1648 * 8 characters or less. To hold the maximum possible 1649 * key name, the buffer should be 256 bytes long. 1650 * 1651 * valueLen: On output, will be set to the size of the "value" data. 1652 * 1653 * value: On output, *value is set to point to location within TXT 1654 * Record bytes that holds the value data. 1655 * 1656 * return value: Returns kDNSServiceErr_NoError on success. 1657 * Returns kDNSServiceErr_NoMemory if keyBufLen is too short. 1658 * Returns kDNSServiceErr_Invalid if index is greater than 1659 * TXTRecordGetCount()-1. 1660 */ 1661 1662 DNSServiceErrorType DNSSD_API TXTRecordGetItemAtIndex 1663 ( 1664 uint16_t txtLen, 1665 const void *txtRecord, 1666 uint16_t index, 1667 uint16_t keyBufLen, 1668 char *key, 1669 uint8_t *valueLen, 1670 const void **value 1671 ); 1672 1673 #ifdef __APPLE_API_PRIVATE 1674 1675 /* 1676 * Mac OS X specific functionality 1677 * 3rd party clients of this API should not depend on future support or availability of this routine 1678 */ 1679 1680 /* DNSServiceSetDefaultDomainForUser() 1681 * 1682 * Set the default domain for the caller's UID. Future browse and registration 1683 * calls by this user that do not specify an explicit domain will browse and 1684 * register in this wide-area domain in addition to .local. In addition, this 1685 * domain will be returned as a Browse domain via domain enumeration calls. 1686 * 1687 * 1688 * Parameters: 1689 * 1690 * flags: Pass kDNSServiceFlagsAdd to add a domain for a user. Call without 1691 * this flag set to clear a previously added domain. 1692 * 1693 * domain: The domain to be used for the caller's UID. 1694 * 1695 * return value: Returns kDNSServiceErr_NoError on succeses, otherwise returns 1696 * an error code indicating the error that occurred 1697 */ 1698 1699 DNSServiceErrorType DNSSD_API DNSServiceSetDefaultDomainForUser 1700 ( 1701 DNSServiceFlags flags, 1702 const char *domain 1703 ); 1704 1705 #endif //__APPLE_API_PRIVATE 1706 1707 // Some C compiler cleverness. We can make the compiler check certain things for us, 1708 // and report errors at compile-time if anything is wrong. The usual way to do this would 1709 // be to use a run-time "if" statement or the conventional run-time "assert" mechanism, but 1710 // then you don't find out what's wrong until you run the software. This way, if the assertion 1711 // condition is false, the array size is negative, and the complier complains immediately. 1712 1713 struct DNS_SD_CompileTimeAssertionChecks 1714 { 1715 char assert0[(sizeof(union _TXTRecordRef_t) == 16) ? 1 : -1]; 1716 }; 1717 1718 #ifdef __cplusplus 1719 } 1720 #endif 1721 1722 #endif /* _DNS_SD_H */ 1723
