1 /* -*- Mode: C; tab-width: 4 -*- 2 * 3 * Copyright (c) 2003-2015 Apple 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 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 30 /*! @header DNS Service Discovery 31 * 32 * @discussion This section describes the functions, callbacks, and data structures 33 * that make up the DNS Service Discovery API. 34 * 35 * The DNS Service Discovery API is part of Bonjour, Apple's implementation 36 * of zero-configuration networking (ZEROCONF). 37 * 38 * Bonjour allows you to register a network service, such as a 39 * printer or file server, so that it can be found by name or browsed 40 * for by service type and domain. Using Bonjour, applications can 41 * discover what services are available on the network, along with 42 * all the information -- such as name, IP address, and port -- 43 * necessary to access a particular service. 44 * 45 * In effect, Bonjour combines the functions of a local DNS server and 46 * AppleTalk. Bonjour allows applications to provide user-friendly printer 47 * and server browsing, among other things, over standard IP networks. 48 * This behavior is a result of combining protocols such as multicast and 49 * DNS to add new functionality to the network (such as multicast DNS). 50 * 51 * Bonjour gives applications easy access to services over local IP 52 * networks without requiring the service or the application to support 53 * an AppleTalk or a Netbeui stack, and without requiring a DNS server 54 * for the local network. 55 */ 56 57 /* _DNS_SD_H contains the API version number for this header file 58 * The API version defined in this header file symbol allows for compile-time 59 * checking, so that C code building with earlier versions of the header file 60 * can avoid compile errors trying to use functions that aren't even defined 61 * in those earlier versions. Similar checks may also be performed at run-time: 62 * => weak linking -- to avoid link failures if run with an earlier 63 * version of the library that's missing some desired symbol, or 64 * => DNSServiceGetProperty(DaemonVersion) -- to verify whether the running daemon 65 * ("system service" on Windows) meets some required minimum functionality level. 66 */ 67 68 #ifndef _DNS_SD_H 69 #define _DNS_SD_H 6254102 70 71 #ifdef __cplusplus 72 extern "C" { 73 #endif 74 75 /* Set to 1 if libdispatch is supported 76 * Note: May also be set by project and/or Makefile 77 */ 78 #ifndef _DNS_SD_LIBDISPATCH 79 #define _DNS_SD_LIBDISPATCH 0 80 #endif /* ndef _DNS_SD_LIBDISPATCH */ 81 82 /* standard calling convention under Win32 is __stdcall */ 83 /* Note: When compiling Intel EFI (Extensible Firmware Interface) under MS Visual Studio, the */ 84 /* _WIN32 symbol is defined by the compiler even though it's NOT compiling code for Windows32 */ 85 #if defined(_WIN32) && !defined(EFI32) && !defined(EFI64) 86 #define DNSSD_API __stdcall 87 #else 88 #define DNSSD_API 89 #endif 90 91 /* stdint.h does not exist on FreeBSD 4.x; its types are defined in sys/types.h instead */ 92 #if defined(__FreeBSD__) && (__FreeBSD__ < 5) 93 #include <sys/types.h> 94 95 /* Likewise, on Sun, standard integer types are in sys/types.h */ 96 #elif defined(__sun__) 97 #include <sys/types.h> 98 99 /* EFI does not have stdint.h, or anything else equivalent */ 100 #elif defined(EFI32) || defined(EFI64) || defined(EFIX64) 101 #include "Tiano.h" 102 #if !defined(_STDINT_H_) 103 typedef UINT8 uint8_t; 104 typedef INT8 int8_t; 105 typedef UINT16 uint16_t; 106 typedef INT16 int16_t; 107 typedef UINT32 uint32_t; 108 typedef INT32 int32_t; 109 #endif 110 /* Windows has its own differences */ 111 #elif defined(_WIN32) 112 #include <windows.h> 113 #define _UNUSED 114 #ifndef _MSL_STDINT_H 115 typedef UINT8 uint8_t; 116 typedef INT8 int8_t; 117 typedef UINT16 uint16_t; 118 typedef INT16 int16_t; 119 typedef UINT32 uint32_t; 120 typedef INT32 int32_t; 121 #endif 122 123 /* All other Posix platforms use stdint.h */ 124 #else 125 #include <stdint.h> 126 #endif 127 128 #if _DNS_SD_LIBDISPATCH 129 #include <dispatch/dispatch.h> 130 #endif 131 132 /* DNSServiceRef, DNSRecordRef 133 * 134 * Opaque internal data types. 135 * Note: client is responsible for serializing access to these structures if 136 * they are shared between concurrent threads. 137 */ 138 139 typedef struct _DNSServiceRef_t *DNSServiceRef; 140 typedef struct _DNSRecordRef_t *DNSRecordRef; 141 142 struct sockaddr; 143 144 /*! @enum General flags 145 * Most DNS-SD API functions and callbacks include a DNSServiceFlags parameter. 146 * As a general rule, any given bit in the 32-bit flags field has a specific fixed meaning, 147 * regardless of the function or callback being used. For any given function or callback, 148 * typically only a subset of the possible flags are meaningful, and all others should be zero. 149 * The discussion section for each API call describes which flags are valid for that call 150 * and callback. In some cases, for a particular call, it may be that no flags are currently 151 * defined, in which case the DNSServiceFlags parameter exists purely to allow future expansion. 152 * In all cases, developers should expect that in future releases, it is possible that new flag 153 * values will be defined, and write code with this in mind. For example, code that tests 154 * if (flags == kDNSServiceFlagsAdd) ... 155 * will fail if, in a future release, another bit in the 32-bit flags field is also set. 156 * The reliable way to test whether a particular bit is set is not with an equality test, 157 * but with a bitwise mask: 158 * if (flags & kDNSServiceFlagsAdd) ... 159 * With the exception of kDNSServiceFlagsValidate, each flag can be valid(be set) 160 * EITHER only as an input to one of the DNSService*() APIs OR only as an output 161 * (provide status) through any of the callbacks used. For example, kDNSServiceFlagsAdd 162 * can be set only as an output in the callback, whereas the kDNSServiceFlagsIncludeP2P 163 * can be set only as an input to the DNSService*() APIs. See comments on kDNSServiceFlagsValidate 164 * defined in enum below. 165 */ 166 enum 167 { 168 kDNSServiceFlagsMoreComing = 0x1, 169 /* MoreComing indicates to a callback that at least one more result is 170 * queued and will be delivered following immediately after this one. 171 * When the MoreComing flag is set, applications should not immediately 172 * update their UI, because this can result in a great deal of ugly flickering 173 * on the screen, and can waste a great deal of CPU time repeatedly updating 174 * the screen with content that is then immediately erased, over and over. 175 * Applications should wait until MoreComing is not set, and then 176 * update their UI when no more changes are imminent. 177 * When MoreComing is not set, that doesn't mean there will be no more 178 * answers EVER, just that there are no more answers immediately 179 * available right now at this instant. If more answers become available 180 * in the future they will be delivered as usual. 181 */ 182 183 kDNSServiceFlagsAdd = 0x2, 184 kDNSServiceFlagsDefault = 0x4, 185 /* Flags for domain enumeration and browse/query reply callbacks. 186 * "Default" applies only to enumeration and is only valid in 187 * conjunction with "Add". An enumeration callback with the "Add" 188 * flag NOT set indicates a "Remove", i.e. the domain is no longer 189 * valid. 190 */ 191 192 kDNSServiceFlagsNoAutoRename = 0x8, 193 /* Flag for specifying renaming behavior on name conflict when registering 194 * non-shared records. By default, name conflicts are automatically handled 195 * by renaming the service. NoAutoRename overrides this behavior - with this 196 * flag set, name conflicts will result in a callback. The NoAutorename flag 197 * is only valid if a name is explicitly specified when registering a service 198 * (i.e. the default name is not used.) 199 */ 200 201 kDNSServiceFlagsShared = 0x10, 202 kDNSServiceFlagsUnique = 0x20, 203 /* Flag for registering individual records on a connected 204 * DNSServiceRef. Shared indicates that there may be multiple records 205 * with this name on the network (e.g. PTR records). Unique indicates that the 206 * record's name is to be unique on the network (e.g. SRV records). 207 */ 208 209 kDNSServiceFlagsBrowseDomains = 0x40, 210 kDNSServiceFlagsRegistrationDomains = 0x80, 211 /* Flags for specifying domain enumeration type in DNSServiceEnumerateDomains. 212 * BrowseDomains enumerates domains recommended for browsing, RegistrationDomains 213 * enumerates domains recommended for registration. 214 */ 215 216 kDNSServiceFlagsLongLivedQuery = 0x100, 217 /* Flag for creating a long-lived unicast query for the DNSServiceQueryRecord call. */ 218 219 kDNSServiceFlagsAllowRemoteQuery = 0x200, 220 /* Flag for creating a record for which we will answer remote queries 221 * (queries from hosts more than one hop away; hosts not directly connected to the local link). 222 */ 223 224 kDNSServiceFlagsForceMulticast = 0x400, 225 /* Flag for signifying that a query or registration should be performed exclusively via multicast 226 * DNS, even for a name in a domain (e.g. foo.apple.com.) that would normally imply unicast DNS. 227 */ 228 229 kDNSServiceFlagsForce = 0x800, // This flag is deprecated. 230 231 kDNSServiceFlagsKnownUnique = 0x800, 232 /* 233 * Client guarantees that record names are unique, so we can skip sending out initial 234 * probe messages. Standard name conflict resolution is still done if a conflict is discovered. 235 * Currently only valid for a DNSServiceRegister call. 236 */ 237 238 kDNSServiceFlagsReturnIntermediates = 0x1000, 239 /* Flag for returning intermediate results. 240 * For example, if a query results in an authoritative NXDomain (name does not exist) 241 * then that result is returned to the client. However the query is not implicitly 242 * cancelled -- it remains active and if the answer subsequently changes 243 * (e.g. because a VPN tunnel is subsequently established) then that positive 244 * result will still be returned to the client. 245 * Similarly, if a query results in a CNAME record, then in addition to following 246 * the CNAME referral, the intermediate CNAME result is also returned to the client. 247 * When this flag is not set, NXDomain errors are not returned, and CNAME records 248 * are followed silently without informing the client of the intermediate steps. 249 * (In earlier builds this flag was briefly calledkDNSServiceFlagsReturnCNAME) 250 */ 251 252 kDNSServiceFlagsNonBrowsable = 0x2000, 253 /* A service registered with the NonBrowsable flag set can be resolved using 254 * DNSServiceResolve(), but will not be discoverable using DNSServiceBrowse(). 255 * This is for cases where the name is actually a GUID; it is found by other means; 256 * there is no end-user benefit to browsing to find a long list of opaque GUIDs. 257 * Using the NonBrowsable flag creates SRV+TXT without the cost of also advertising 258 * an associated PTR record. 259 */ 260 261 kDNSServiceFlagsShareConnection = 0x4000, 262 /* For efficiency, clients that perform many concurrent operations may want to use a 263 * single Unix Domain Socket connection with the background daemon, instead of having a 264 * separate connection for each independent operation. To use this mode, clients first 265 * call DNSServiceCreateConnection(&MainRef) to initialize the main DNSServiceRef. 266 * For each subsequent operation that is to share that same connection, the client copies 267 * the MainRef, and then passes the address of that copy, setting the ShareConnection flag 268 * to tell the library that this DNSServiceRef is not a typical uninitialized DNSServiceRef; 269 * it's a copy of an existing DNSServiceRef whose connection information should be reused. 270 * 271 * For example: 272 * 273 * DNSServiceErrorType error; 274 * DNSServiceRef MainRef; 275 * error = DNSServiceCreateConnection(&MainRef); 276 * if (error) ... 277 * DNSServiceRef BrowseRef = MainRef; // Important: COPY the primary DNSServiceRef first... 278 * error = DNSServiceBrowse(&BrowseRef, kDNSServiceFlagsShareConnection, ...); // then use the copy 279 * if (error) ... 280 * ... 281 * DNSServiceRefDeallocate(BrowseRef); // Terminate the browse operation 282 * DNSServiceRefDeallocate(MainRef); // Terminate the shared connection 283 * Also see Point 4.(Don't Double-Deallocate if the MainRef has been Deallocated) in Notes below: 284 * 285 * Notes: 286 * 287 * 1. Collective kDNSServiceFlagsMoreComing flag 288 * When callbacks are invoked using a shared DNSServiceRef, the 289 * kDNSServiceFlagsMoreComing flag applies collectively to *all* active 290 * operations sharing the same parent DNSServiceRef. If the MoreComing flag is 291 * set it means that there are more results queued on this parent DNSServiceRef, 292 * but not necessarily more results for this particular callback function. 293 * The implication of this for client programmers is that when a callback 294 * is invoked with the MoreComing flag set, the code should update its 295 * internal data structures with the new result, and set a variable indicating 296 * that its UI needs to be updated. Then, later when a callback is eventually 297 * invoked with the MoreComing flag not set, the code should update *all* 298 * stale UI elements related to that shared parent DNSServiceRef that need 299 * updating, not just the UI elements related to the particular callback 300 * that happened to be the last one to be invoked. 301 * 302 * 2. Canceling operations and kDNSServiceFlagsMoreComing 303 * Whenever you cancel any operation for which you had deferred UI updates 304 * waiting because of a kDNSServiceFlagsMoreComing flag, you should perform 305 * those deferred UI updates. This is because, after cancelling the operation, 306 * you can no longer wait for a callback *without* MoreComing set, to tell 307 * you do perform your deferred UI updates (the operation has been canceled, 308 * so there will be no more callbacks). An implication of the collective 309 * kDNSServiceFlagsMoreComing flag for shared connections is that this 310 * guideline applies more broadly -- any time you cancel an operation on 311 * a shared connection, you should perform all deferred UI updates for all 312 * operations sharing that connection. This is because the MoreComing flag 313 * might have been referring to events coming for the operation you canceled, 314 * which will now not be coming because the operation has been canceled. 315 * 316 * 3. Only share DNSServiceRef's created with DNSServiceCreateConnection 317 * Calling DNSServiceCreateConnection(&ref) creates a special shareable DNSServiceRef. 318 * DNSServiceRef's created by other calls like DNSServiceBrowse() or DNSServiceResolve() 319 * cannot be shared by copying them and using kDNSServiceFlagsShareConnection. 320 * 321 * 4. Don't Double-Deallocate if the MainRef has been Deallocated 322 * Calling DNSServiceRefDeallocate(ref) for a particular operation's DNSServiceRef terminates 323 * just that operation. Calling DNSServiceRefDeallocate(ref) for the main shared DNSServiceRef 324 * (the parent DNSServiceRef, originally created by DNSServiceCreateConnection(&ref)) 325 * automatically terminates the shared connection and all operations that were still using it. 326 * After doing this, DO NOT then attempt to deallocate any remaining subordinate DNSServiceRef's. 327 * The memory used by those subordinate DNSServiceRef's has already been freed, so any attempt 328 * to do a DNSServiceRefDeallocate (or any other operation) on them will result in accesses 329 * to freed memory, leading to crashes or other equally undesirable results. 330 * 331 * 5. Thread Safety 332 * The dns_sd.h API does not presuppose any particular threading model, and consequently 333 * does no locking of its own (which would require linking some specific threading library). 334 * If client code calls API routines on the same DNSServiceRef concurrently 335 * from multiple threads, it is the client's responsibility to use a mutext 336 * lock or take similar appropriate precautions to serialize those calls. 337 */ 338 339 kDNSServiceFlagsSuppressUnusable = 0x8000, 340 /* 341 * This flag is meaningful only in DNSServiceQueryRecord which suppresses unusable queries on the 342 * wire. If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name) 343 * but this host has no routable IPv6 address, then the call will not try to look up IPv6 addresses 344 * for "hostname", since any addresses it found would be unlikely to be of any use anyway. Similarly, 345 * if this host has no routable IPv4 address, the call will not try to look up IPv4 addresses for 346 * "hostname". 347 */ 348 349 kDNSServiceFlagsTimeout = 0x10000, 350 /* 351 * When kDNServiceFlagsTimeout is passed to DNSServiceQueryRecord or DNSServiceGetAddrInfo, the query is 352 * stopped after a certain number of seconds have elapsed. The time at which the query will be stopped 353 * is determined by the system and cannot be configured by the user. The query will be stopped irrespective 354 * of whether a response was given earlier or not. When the query is stopped, the callback will be called 355 * with an error code of kDNSServiceErr_Timeout and a NULL sockaddr will be returned for DNSServiceGetAddrInfo 356 * and zero length rdata will be returned for DNSServiceQueryRecord. 357 */ 358 359 kDNSServiceFlagsIncludeP2P = 0x20000, 360 /* 361 * Include P2P interfaces when kDNSServiceInterfaceIndexAny is specified. 362 * By default, specifying kDNSServiceInterfaceIndexAny does not include P2P interfaces. 363 */ 364 365 kDNSServiceFlagsWakeOnResolve = 0x40000, 366 /* 367 * This flag is meaningful only in DNSServiceResolve. When set, it tries to send a magic packet 368 * to wake up the client. 369 */ 370 371 kDNSServiceFlagsBackgroundTrafficClass = 0x80000, 372 /* 373 * This flag is meaningful for Unicast DNS queries. When set, it uses the background traffic 374 * class for packets that service the request. 375 */ 376 377 kDNSServiceFlagsIncludeAWDL = 0x100000, 378 /* 379 * Include AWDL interface when kDNSServiceInterfaceIndexAny is specified. 380 */ 381 382 kDNSServiceFlagsValidate = 0x200000, 383 /* 384 * This flag is meaningful in DNSServiceGetAddrInfo and DNSServiceQueryRecord. This is the ONLY flag to be valid 385 * as an input to the APIs and also an output through the callbacks in the APIs. 386 * 387 * When this flag is passed to DNSServiceQueryRecord and DNSServiceGetAddrInfo to resolve unicast names, 388 * the response will be validated using DNSSEC. The validation results are delivered using the flags field in 389 * the callback and kDNSServiceFlagsValidate is marked in the flags to indicate that DNSSEC status is also available. 390 * When the callback is called to deliver the query results, the validation results may or may not be available. 391 * If it is not delivered along with the results, the validation status is delivered when the validation completes. 392 * 393 * When the validation results are delivered in the callback, it is indicated by marking the flags with 394 * kDNSServiceFlagsValidate and kDNSServiceFlagsAdd along with the DNSSEC status flags (described below) and a NULL 395 * sockaddr will be returned for DNSServiceGetAddrInfo and zero length rdata will be returned for DNSServiceQueryRecord. 396 * DNSSEC validation results are for the whole RRSet and not just individual records delivered in the callback. When 397 * kDNSServiceFlagsAdd is not set in the flags, applications should implicitly assume that the DNSSEC status of the 398 * RRSet that has been delivered up until that point is not valid anymore, till another callback is called with 399 * kDNSServiceFlagsAdd and kDNSServiceFlagsValidate. 400 * 401 * The following four flags indicate the status of the DNSSEC validation and marked in the flags field of the callback. 402 * When any of the four flags is set, kDNSServiceFlagsValidate will also be set. To check the validation status, the 403 * other applicable output flags should be masked. See kDNSServiceOutputFlags below. 404 */ 405 406 kDNSServiceFlagsSecure = 0x200010, 407 /* 408 * The response has been validated by verifying all the signaures in the response and was able to 409 * build a successful authentication chain starting from a known trust anchor. 410 */ 411 412 kDNSServiceFlagsInsecure = 0x200020, 413 /* 414 * A chain of trust cannot be built starting from a known trust anchor to the response. 415 */ 416 417 kDNSServiceFlagsBogus = 0x200040, 418 /* 419 * If the response cannot be verified to be secure due to expired signatures, missing signatures etc., 420 * then the results are considered to be bogus. 421 */ 422 423 kDNSServiceFlagsIndeterminate = 0x200080, 424 /* 425 * There is no valid trust anchor that can be used to determine whether a response is secure or not. 426 */ 427 428 kDNSServiceFlagsUnicastResponse = 0x400000, 429 /* 430 * Request unicast response to query. 431 */ 432 kDNSServiceFlagsValidateOptional = 0x800000, 433 434 /* 435 * This flag is identical to kDNSServiceFlagsValidate except for the case where the response 436 * cannot be validated. If this flag is set in DNSServiceQueryRecord or DNSServiceGetAddrInfo, 437 * the DNSSEC records will be requested for validation. If they cannot be received for some reason 438 * during the validation (e.g., zone is not signed, zone is signed but cannot be traced back to 439 * root, recursive server does not understand DNSSEC etc.), then this will fallback to the default 440 * behavior where the validation will not be performed and no DNSSEC results will be provided. 441 * 442 * If the zone is signed and there is a valid path to a known trust anchor configured in the system 443 * and the application requires DNSSEC validation irrespective of the DNSSEC awareness in the current 444 * network, then this option MUST not be used. This is only intended to be used during the transition 445 * period where the different nodes participating in the DNS resolution may not understand DNSSEC or 446 * managed properly (e.g. missing DS record) but still want to be able to resolve DNS successfully. 447 */ 448 449 kDNSServiceFlagsWakeOnlyService = 0x1000000, 450 /* 451 * This flag is meaningful only in DNSServiceRegister. When set, the service will not be registered 452 * with sleep proxy server during sleep. 453 */ 454 455 kDNSServiceFlagsThresholdOne = 0x2000000, 456 kDNSServiceFlagsThresholdFinder = 0x4000000, 457 kDNSServiceFlagsThresholdReached = kDNSServiceFlagsThresholdOne, 458 /* 459 * kDNSServiceFlagsThresholdOne is meaningful only in DNSServiceBrowse. When set, 460 * the system will stop issuing browse queries on the network once the number 461 * of answers returned is one or more. It will issue queries on the network 462 * again if the number of answers drops to zero. 463 * This flag is for Apple internal use only. Third party developers 464 * should not rely on this behavior being supported in any given software release. 465 * 466 * kDNSServiceFlagsThresholdFinder is meaningful only in DNSServiceBrowse. When set, 467 * the system will stop issuing browse queries on the network once the number 468 * of answers has reached the threshold set for Finder. 469 * It will issue queries on the network again if the number of answers drops below 470 * this threshold. 471 * This flag is for Apple internal use only. Third party developers 472 * should not rely on this behavior being supported in any given software release. 473 * 474 * When kDNSServiceFlagsThresholdReached is set in the client callback add or remove event, 475 * it indicates that the browse answer threshold has been reached and no 476 * browse requests will be generated on the network until the number of answers falls 477 * below the threshold value. Add and remove events can still occur based 478 * on incoming Bonjour traffic observed by the system. 479 * The set of services return to the client is not guaranteed to represent the 480 * entire set of services present on the network once the threshold has been reached. 481 * 482 * Note, while kDNSServiceFlagsThresholdReached and kDNSServiceFlagsThresholdOne 483 * have the same value, there isn't a conflict because kDNSServiceFlagsThresholdReached 484 * is only set in the callbacks and kDNSServiceFlagsThresholdOne is only set on 485 * input to a DNSServiceBrowse call. 486 */ 487 kDNSServiceFlagsDenyCellular = 0x8000000, 488 /* 489 * This flag is meaningful only for Unicast DNS queries. When set, the kernel will restrict 490 * DNS resolutions on the cellular interface for that request. 491 */ 492 493 kDNSServiceFlagsServiceIndex = 0x10000000, 494 /* 495 * This flag is meaningful only for DNSServiceGetAddrInfo() for Unicast DNS queries. 496 * When set, DNSServiceGetAddrInfo() will interpret the "interfaceIndex" argument of the call 497 * as the "serviceIndex". 498 */ 499 500 kDNSServiceFlagsDenyExpensive = 0x20000000, 501 /* 502 * This flag is meaningful only for Unicast DNS queries. When set, the kernel will restrict 503 * DNS resolutions on interfaces defined as expensive for that request. 504 */ 505 506 kDNSServiceFlagsPathEvaluationDone = 0x40000000 507 /* 508 * This flag is meaningful for only Unicast DNS queries. 509 * When set, it indicates that Network PathEvaluation has already been performed. 510 */ 511 512 }; 513 514 #define kDNSServiceOutputFlags (kDNSServiceFlagsValidate | kDNSServiceFlagsValidateOptional | kDNSServiceFlagsMoreComing | kDNSServiceFlagsAdd | kDNSServiceFlagsDefault) 515 /* All the output flags excluding the DNSSEC Status flags. Typically used to check DNSSEC Status */ 516 517 /* Possible protocol values */ 518 enum 519 { 520 /* for DNSServiceGetAddrInfo() */ 521 kDNSServiceProtocol_IPv4 = 0x01, 522 kDNSServiceProtocol_IPv6 = 0x02, 523 /* 0x04 and 0x08 reserved for future internetwork protocols */ 524 525 /* for DNSServiceNATPortMappingCreate() */ 526 kDNSServiceProtocol_UDP = 0x10, 527 kDNSServiceProtocol_TCP = 0x20 528 /* 0x40 and 0x80 reserved for future transport protocols, e.g. SCTP [RFC 2960] 529 * or DCCP [RFC 4340]. If future NAT gateways are created that support port 530 * mappings for these protocols, new constants will be defined here. 531 */ 532 }; 533 534 /* 535 * The values for DNS Classes and Types are listed in RFC 1035, and are available 536 * on every OS in its DNS header file. Unfortunately every OS does not have the 537 * same header file containing DNS Class and Type constants, and the names of 538 * the constants are not consistent. For example, BIND 8 uses "T_A", 539 * BIND 9 uses "ns_t_a", Windows uses "DNS_TYPE_A", etc. 540 * For this reason, these constants are also listed here, so that code using 541 * the DNS-SD programming APIs can use these constants, so that the same code 542 * can compile on all our supported platforms. 543 */ 544 545 enum 546 { 547 kDNSServiceClass_IN = 1 /* Internet */ 548 }; 549 550 enum 551 { 552 kDNSServiceType_A = 1, /* Host address. */ 553 kDNSServiceType_NS = 2, /* Authoritative server. */ 554 kDNSServiceType_MD = 3, /* Mail destination. */ 555 kDNSServiceType_MF = 4, /* Mail forwarder. */ 556 kDNSServiceType_CNAME = 5, /* Canonical name. */ 557 kDNSServiceType_SOA = 6, /* Start of authority zone. */ 558 kDNSServiceType_MB = 7, /* Mailbox domain name. */ 559 kDNSServiceType_MG = 8, /* Mail group member. */ 560 kDNSServiceType_MR = 9, /* Mail rename name. */ 561 kDNSServiceType_NULL = 10, /* Null resource record. */ 562 kDNSServiceType_WKS = 11, /* Well known service. */ 563 kDNSServiceType_PTR = 12, /* Domain name pointer. */ 564 kDNSServiceType_HINFO = 13, /* Host information. */ 565 kDNSServiceType_MINFO = 14, /* Mailbox information. */ 566 kDNSServiceType_MX = 15, /* Mail routing information. */ 567 kDNSServiceType_TXT = 16, /* One or more text strings (NOT "zero or more..."). */ 568 kDNSServiceType_RP = 17, /* Responsible person. */ 569 kDNSServiceType_AFSDB = 18, /* AFS cell database. */ 570 kDNSServiceType_X25 = 19, /* X_25 calling address. */ 571 kDNSServiceType_ISDN = 20, /* ISDN calling address. */ 572 kDNSServiceType_RT = 21, /* Router. */ 573 kDNSServiceType_NSAP = 22, /* NSAP address. */ 574 kDNSServiceType_NSAP_PTR = 23, /* Reverse NSAP lookup (deprecated). */ 575 kDNSServiceType_SIG = 24, /* Security signature. */ 576 kDNSServiceType_KEY = 25, /* Security key. */ 577 kDNSServiceType_PX = 26, /* X.400 mail mapping. */ 578 kDNSServiceType_GPOS = 27, /* Geographical position (withdrawn). */ 579 kDNSServiceType_AAAA = 28, /* IPv6 Address. */ 580 kDNSServiceType_LOC = 29, /* Location Information. */ 581 kDNSServiceType_NXT = 30, /* Next domain (security). */ 582 kDNSServiceType_EID = 31, /* Endpoint identifier. */ 583 kDNSServiceType_NIMLOC = 32, /* Nimrod Locator. */ 584 kDNSServiceType_SRV = 33, /* Server Selection. */ 585 kDNSServiceType_ATMA = 34, /* ATM Address */ 586 kDNSServiceType_NAPTR = 35, /* Naming Authority PoinTeR */ 587 kDNSServiceType_KX = 36, /* Key Exchange */ 588 kDNSServiceType_CERT = 37, /* Certification record */ 589 kDNSServiceType_A6 = 38, /* IPv6 Address (deprecated) */ 590 kDNSServiceType_DNAME = 39, /* Non-terminal DNAME (for IPv6) */ 591 kDNSServiceType_SINK = 40, /* Kitchen sink (experimental) */ 592 kDNSServiceType_OPT = 41, /* EDNS0 option (meta-RR) */ 593 kDNSServiceType_APL = 42, /* Address Prefix List */ 594 kDNSServiceType_DS = 43, /* Delegation Signer */ 595 kDNSServiceType_SSHFP = 44, /* SSH Key Fingerprint */ 596 kDNSServiceType_IPSECKEY = 45, /* IPSECKEY */ 597 kDNSServiceType_RRSIG = 46, /* RRSIG */ 598 kDNSServiceType_NSEC = 47, /* Denial of Existence */ 599 kDNSServiceType_DNSKEY = 48, /* DNSKEY */ 600 kDNSServiceType_DHCID = 49, /* DHCP Client Identifier */ 601 kDNSServiceType_NSEC3 = 50, /* Hashed Authenticated Denial of Existence */ 602 kDNSServiceType_NSEC3PARAM = 51, /* Hashed Authenticated Denial of Existence */ 603 604 kDNSServiceType_HIP = 55, /* Host Identity Protocol */ 605 606 kDNSServiceType_SPF = 99, /* Sender Policy Framework for E-Mail */ 607 kDNSServiceType_UINFO = 100, /* IANA-Reserved */ 608 kDNSServiceType_UID = 101, /* IANA-Reserved */ 609 kDNSServiceType_GID = 102, /* IANA-Reserved */ 610 kDNSServiceType_UNSPEC = 103, /* IANA-Reserved */ 611 612 kDNSServiceType_TKEY = 249, /* Transaction key */ 613 kDNSServiceType_TSIG = 250, /* Transaction signature. */ 614 kDNSServiceType_IXFR = 251, /* Incremental zone transfer. */ 615 kDNSServiceType_AXFR = 252, /* Transfer zone of authority. */ 616 kDNSServiceType_MAILB = 253, /* Transfer mailbox records. */ 617 kDNSServiceType_MAILA = 254, /* Transfer mail agent records. */ 618 kDNSServiceType_ANY = 255 /* Wildcard match. */ 619 }; 620 621 /* possible error code values */ 622 enum 623 { 624 kDNSServiceErr_NoError = 0, 625 kDNSServiceErr_Unknown = -65537, /* 0xFFFE FFFF */ 626 kDNSServiceErr_NoSuchName = -65538, 627 kDNSServiceErr_NoMemory = -65539, 628 kDNSServiceErr_BadParam = -65540, 629 kDNSServiceErr_BadReference = -65541, 630 kDNSServiceErr_BadState = -65542, 631 kDNSServiceErr_BadFlags = -65543, 632 kDNSServiceErr_Unsupported = -65544, 633 kDNSServiceErr_NotInitialized = -65545, 634 kDNSServiceErr_AlreadyRegistered = -65547, 635 kDNSServiceErr_NameConflict = -65548, 636 kDNSServiceErr_Invalid = -65549, 637 kDNSServiceErr_Firewall = -65550, 638 kDNSServiceErr_Incompatible = -65551, /* client library incompatible with daemon */ 639 kDNSServiceErr_BadInterfaceIndex = -65552, 640 kDNSServiceErr_Refused = -65553, 641 kDNSServiceErr_NoSuchRecord = -65554, 642 kDNSServiceErr_NoAuth = -65555, 643 kDNSServiceErr_NoSuchKey = -65556, 644 kDNSServiceErr_NATTraversal = -65557, 645 kDNSServiceErr_DoubleNAT = -65558, 646 kDNSServiceErr_BadTime = -65559, /* Codes up to here existed in Tiger */ 647 kDNSServiceErr_BadSig = -65560, 648 kDNSServiceErr_BadKey = -65561, 649 kDNSServiceErr_Transient = -65562, 650 kDNSServiceErr_ServiceNotRunning = -65563, /* Background daemon not running */ 651 kDNSServiceErr_NATPortMappingUnsupported = -65564, /* NAT doesn't support PCP, NAT-PMP or UPnP */ 652 kDNSServiceErr_NATPortMappingDisabled = -65565, /* NAT supports PCP, NAT-PMP or UPnP, but it's disabled by the administrator */ 653 kDNSServiceErr_NoRouter = -65566, /* No router currently configured (probably no network connectivity) */ 654 kDNSServiceErr_PollingMode = -65567, 655 kDNSServiceErr_Timeout = -65568 656 657 /* mDNS Error codes are in the range 658 * FFFE FF00 (-65792) to FFFE FFFF (-65537) */ 659 }; 660 661 /* Maximum length, in bytes, of a service name represented as a */ 662 /* literal C-String, including the terminating NULL at the end. */ 663 664 #define kDNSServiceMaxServiceName 64 665 666 /* Maximum length, in bytes, of a domain name represented as an *escaped* C-String */ 667 /* including the final trailing dot, and the C-String terminating NULL at the end. */ 668 669 #define kDNSServiceMaxDomainName 1009 670 671 /* 672 * Notes on DNS Name Escaping 673 * -- or -- 674 * "Why is kDNSServiceMaxDomainName 1009, when the maximum legal domain name is 256 bytes?" 675 * 676 * All strings used in the DNS-SD APIs are UTF-8 strings. Apart from the exceptions noted below, 677 * the APIs expect the strings to be properly escaped, using the conventional DNS escaping rules: 678 * 679 * '\\' represents a single literal '\' in the name 680 * '\.' represents a single literal '.' in the name 681 * '\ddd', where ddd is a three-digit decimal value from 000 to 255, 682 * represents a single literal byte with that value. 683 * A bare unescaped '.' is a label separator, marking a boundary between domain and subdomain. 684 * 685 * The exceptions, that do not use escaping, are the routines where the full 686 * DNS name of a resource is broken, for convenience, into servicename/regtype/domain. 687 * In these routines, the "servicename" is NOT escaped. It does not need to be, since 688 * it is, by definition, just a single literal string. Any characters in that string 689 * represent exactly what they are. The "regtype" portion is, technically speaking, 690 * escaped, but since legal regtypes are only allowed to contain letters, digits, 691 * and hyphens, there is nothing to escape, so the issue is moot. The "domain" 692 * portion is also escaped, though most domains in use on the public Internet 693 * today, like regtypes, don't contain any characters that need to be escaped. 694 * As DNS-SD becomes more popular, rich-text domains for service discovery will 695 * become common, so software should be written to cope with domains with escaping. 696 * 697 * The servicename may be up to 63 bytes of UTF-8 text (not counting the C-String 698 * terminating NULL at the end). The regtype is of the form _service._tcp or 699 * _service._udp, where the "service" part is 1-15 characters, which may be 700 * letters, digits, or hyphens. The domain part of the three-part name may be 701 * any legal domain, providing that the resulting servicename+regtype+domain 702 * name does not exceed 256 bytes. 703 * 704 * For most software, these issues are transparent. When browsing, the discovered 705 * servicenames should simply be displayed as-is. When resolving, the discovered 706 * servicename/regtype/domain are simply passed unchanged to DNSServiceResolve(). 707 * When a DNSServiceResolve() succeeds, the returned fullname is already in 708 * the correct format to pass to standard system DNS APIs such as res_query(). 709 * For converting from servicename/regtype/domain to a single properly-escaped 710 * full DNS name, the helper function DNSServiceConstructFullName() is provided. 711 * 712 * The following (highly contrived) example illustrates the escaping process. 713 * Suppose you have an service called "Dr. Smith\Dr. Johnson", of type "_ftp._tcp" 714 * in subdomain "4th. Floor" of subdomain "Building 2" of domain "apple.com." 715 * The full (escaped) DNS name of this service's SRV record would be: 716 * Dr\.\032Smith\\Dr\.\032Johnson._ftp._tcp.4th\.\032Floor.Building\0322.apple.com. 717 */ 718 719 720 /* 721 * Constants for specifying an interface index 722 * 723 * Specific interface indexes are identified via a 32-bit unsigned integer returned 724 * by the if_nametoindex() family of calls. 725 * 726 * If the client passes 0 for interface index, that means "do the right thing", 727 * which (at present) means, "if the name is in an mDNS local multicast domain 728 * (e.g. 'local.', '254.169.in-addr.arpa.', '{8,9,A,B}.E.F.ip6.arpa.') then multicast 729 * on all applicable interfaces, otherwise send via unicast to the appropriate 730 * DNS server." Normally, most clients will use 0 for interface index to 731 * automatically get the default sensible behaviour. 732 * 733 * If the client passes a positive interface index, then that indicates to do the 734 * operation only on that one specified interface. 735 * 736 * If the client passes kDNSServiceInterfaceIndexLocalOnly when registering 737 * a service, then that service will be found *only* by other local clients 738 * on the same machine that are browsing using kDNSServiceInterfaceIndexLocalOnly 739 * or kDNSServiceInterfaceIndexAny. 740 * If a client has a 'private' service, accessible only to other processes 741 * running on the same machine, this allows the client to advertise that service 742 * in a way such that it does not inadvertently appear in service lists on 743 * all the other machines on the network. 744 * 745 * If the client passes kDNSServiceInterfaceIndexLocalOnly when browsing 746 * then it will find *all* records registered on that same local machine. 747 * Clients explicitly wishing to discover *only* LocalOnly services can 748 * accomplish this by inspecting the interfaceIndex of each service reported 749 * to their DNSServiceBrowseReply() callback function, and discarding those 750 * where the interface index is not kDNSServiceInterfaceIndexLocalOnly. 751 * 752 * kDNSServiceInterfaceIndexP2P is meaningful only in Browse, QueryRecord, Register, 753 * and Resolve operations. It should not be used in other DNSService APIs. 754 * 755 * - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceBrowse or 756 * DNSServiceQueryRecord, it restricts the operation to P2P. 757 * 758 * - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceRegister, it is 759 * mapped internally to kDNSServiceInterfaceIndexAny with the kDNSServiceFlagsIncludeP2P 760 * set. 761 * 762 * - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceResolve, it is 763 * mapped internally to kDNSServiceInterfaceIndexAny with the kDNSServiceFlagsIncludeP2P 764 * set, because resolving a P2P service may create and/or enable an interface whose 765 * index is not known a priori. The resolve callback will indicate the index of the 766 * interface via which the service can be accessed. 767 * 768 * If applications pass kDNSServiceInterfaceIndexAny to DNSServiceBrowse 769 * or DNSServiceQueryRecord, they must set the kDNSServiceFlagsIncludeP2P flag 770 * to include P2P. In this case, if a service instance or the record being queried 771 * is found over P2P, the resulting ADD event will indicate kDNSServiceInterfaceIndexP2P 772 * as the interface index. 773 */ 774 775 #define kDNSServiceInterfaceIndexAny 0 776 #define kDNSServiceInterfaceIndexLocalOnly ((uint32_t)-1) 777 #define kDNSServiceInterfaceIndexUnicast ((uint32_t)-2) 778 #define kDNSServiceInterfaceIndexP2P ((uint32_t)-3) 779 780 typedef uint32_t DNSServiceFlags; 781 typedef uint32_t DNSServiceProtocol; 782 typedef int32_t DNSServiceErrorType; 783 784 785 /********************************************************************************************* 786 * 787 * Version checking 788 * 789 *********************************************************************************************/ 790 791 /* DNSServiceGetProperty() Parameters: 792 * 793 * property: The requested property. 794 * Currently the only property defined is kDNSServiceProperty_DaemonVersion. 795 * 796 * result: Place to store result. 797 * For retrieving DaemonVersion, this should be the address of a uint32_t. 798 * 799 * size: Pointer to uint32_t containing size of the result location. 800 * For retrieving DaemonVersion, this should be sizeof(uint32_t). 801 * On return the uint32_t is updated to the size of the data returned. 802 * For DaemonVersion, the returned size is always sizeof(uint32_t), but 803 * future properties could be defined which return variable-sized results. 804 * 805 * return value: Returns kDNSServiceErr_NoError on success, or kDNSServiceErr_ServiceNotRunning 806 * if the daemon (or "system service" on Windows) is not running. 807 */ 808 809 DNSServiceErrorType DNSSD_API DNSServiceGetProperty 810 ( 811 const char *property, /* Requested property (i.e. kDNSServiceProperty_DaemonVersion) */ 812 void *result, /* Pointer to place to store result */ 813 uint32_t *size /* size of result location */ 814 ); 815 816 /* 817 * When requesting kDNSServiceProperty_DaemonVersion, the result pointer must point 818 * to a 32-bit unsigned integer, and the size parameter must be set to sizeof(uint32_t). 819 * 820 * On return, the 32-bit unsigned integer contains the API version number 821 * 822 * For example, Mac OS X 10.4.9 has API version 1080400. 823 * This allows applications to do simple greater-than and less-than comparisons: 824 * e.g. an application that requires at least API version 1080400 can check: 825 * if (version >= 1080400) ... 826 * 827 * Example usage: 828 * uint32_t version; 829 * uint32_t size = sizeof(version); 830 * DNSServiceErrorType err = DNSServiceGetProperty(kDNSServiceProperty_DaemonVersion, &version, &size); 831 * if (!err) printf("DNS_SD API version is %d.%d\n", version / 10000, version / 100 % 100); 832 */ 833 834 #define kDNSServiceProperty_DaemonVersion "DaemonVersion" 835 836 837 // Map the source port of the local UDP socket that was opened for sending the DNS query 838 // to the process ID of the application that triggered the DNS resolution. 839 // 840 /* DNSServiceGetPID() Parameters: 841 * 842 * srcport: Source port (in network byte order) of the UDP socket that was created by 843 * the daemon to send the DNS query on the wire. 844 * 845 * pid: Process ID of the application that started the name resolution which triggered 846 * the daemon to send the query on the wire. The value can be -1 if the srcport 847 * cannot be mapped. 848 * 849 * return value: Returns kDNSServiceErr_NoError on success, or kDNSServiceErr_ServiceNotRunning 850 * if the daemon is not running. The value of the pid is undefined if the return 851 * value has error. 852 */ 853 DNSServiceErrorType DNSSD_API DNSServiceGetPID 854 ( 855 uint16_t srcport, 856 int32_t *pid 857 ); 858 859 /********************************************************************************************* 860 * 861 * Unix Domain Socket access, DNSServiceRef deallocation, and data processing functions 862 * 863 *********************************************************************************************/ 864 865 /* DNSServiceRefSockFD() 866 * 867 * Access underlying Unix domain socket for an initialized DNSServiceRef. 868 * The DNS Service Discovery implementation uses this socket to communicate between the client and 869 * the daemon. The application MUST NOT directly read from or write to this socket. 870 * Access to the socket is provided so that it can be used as a kqueue event source, a CFRunLoop 871 * event source, in a select() loop, etc. When the underlying event management subsystem (kqueue/ 872 * select/CFRunLoop etc.) indicates to the client that data is available for reading on the 873 * socket, the client should call DNSServiceProcessResult(), which will extract the daemon's 874 * reply from the socket, and pass it to the appropriate application callback. By using a run 875 * loop or select(), results from the daemon can be processed asynchronously. Alternatively, 876 * a client can choose to fork a thread and have it loop calling "DNSServiceProcessResult(ref);" 877 * If DNSServiceProcessResult() is called when no data is available for reading on the socket, it 878 * will block until data does become available, and then process the data and return to the caller. 879 * The application is reponsible for checking the return value of DNSServiceProcessResult() to determine 880 * if the socket is valid and if it should continue to process data on the socket. 881 * When data arrives on the socket, the client is responsible for calling DNSServiceProcessResult(ref) 882 * in a timely fashion -- if the client allows a large backlog of data to build up the daemon 883 * may terminate the connection. 884 * 885 * sdRef: A DNSServiceRef initialized by any of the DNSService calls. 886 * 887 * return value: The DNSServiceRef's underlying socket descriptor, or -1 on 888 * error. 889 */ 890 891 int DNSSD_API DNSServiceRefSockFD(DNSServiceRef sdRef); 892 893 894 /* DNSServiceProcessResult() 895 * 896 * Read a reply from the daemon, calling the appropriate application callback. This call will 897 * block until the daemon's response is received. Use DNSServiceRefSockFD() in 898 * conjunction with a run loop or select() to determine the presence of a response from the 899 * server before calling this function to process the reply without blocking. Call this function 900 * at any point if it is acceptable to block until the daemon's response arrives. Note that the 901 * client is responsible for ensuring that DNSServiceProcessResult() is called whenever there is 902 * a reply from the daemon - the daemon may terminate its connection with a client that does not 903 * process the daemon's responses. 904 * 905 * sdRef: A DNSServiceRef initialized by any of the DNSService calls 906 * that take a callback parameter. 907 * 908 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns 909 * an error code indicating the specific failure that occurred. 910 */ 911 912 DNSServiceErrorType DNSSD_API DNSServiceProcessResult(DNSServiceRef sdRef); 913 914 915 /* DNSServiceRefDeallocate() 916 * 917 * Terminate a connection with the daemon and free memory associated with the DNSServiceRef. 918 * Any services or records registered with this DNSServiceRef will be deregistered. Any 919 * Browse, Resolve, or Query operations called with this reference will be terminated. 920 * 921 * Note: If the reference's underlying socket is used in a run loop or select() call, it should 922 * be removed BEFORE DNSServiceRefDeallocate() is called, as this function closes the reference's 923 * socket. 924 * 925 * Note: If the reference was initialized with DNSServiceCreateConnection(), any DNSRecordRefs 926 * created via this reference will be invalidated by this call - the resource records are 927 * deregistered, and their DNSRecordRefs may not be used in subsequent functions. Similarly, 928 * if the reference was initialized with DNSServiceRegister, and an extra resource record was 929 * added to the service via DNSServiceAddRecord(), the DNSRecordRef created by the Add() call 930 * is invalidated when this function is called - the DNSRecordRef may not be used in subsequent 931 * functions. 932 * 933 * Note: This call is to be used only with the DNSServiceRef defined by this API. 934 * 935 * sdRef: A DNSServiceRef initialized by any of the DNSService calls. 936 * 937 */ 938 939 void DNSSD_API DNSServiceRefDeallocate(DNSServiceRef sdRef); 940 941 942 /********************************************************************************************* 943 * 944 * Domain Enumeration 945 * 946 *********************************************************************************************/ 947 948 /* DNSServiceEnumerateDomains() 949 * 950 * Asynchronously enumerate domains available for browsing and registration. 951 * 952 * The enumeration MUST be cancelled via DNSServiceRefDeallocate() when no more domains 953 * are to be found. 954 * 955 * Note that the names returned are (like all of DNS-SD) UTF-8 strings, 956 * and are escaped using standard DNS escaping rules. 957 * (See "Notes on DNS Name Escaping" earlier in this file for more details.) 958 * A graphical browser displaying a hierarchical tree-structured view should cut 959 * the names at the bare dots to yield individual labels, then de-escape each 960 * label according to the escaping rules, and then display the resulting UTF-8 text. 961 * 962 * DNSServiceDomainEnumReply Callback Parameters: 963 * 964 * sdRef: The DNSServiceRef initialized by DNSServiceEnumerateDomains(). 965 * 966 * flags: Possible values are: 967 * kDNSServiceFlagsMoreComing 968 * kDNSServiceFlagsAdd 969 * kDNSServiceFlagsDefault 970 * 971 * interfaceIndex: Specifies the interface on which the domain exists. (The index for a given 972 * interface is determined via the if_nametoindex() family of calls.) 973 * 974 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise indicates 975 * the failure that occurred (other parameters are undefined if errorCode is nonzero). 976 * 977 * replyDomain: The name of the domain. 978 * 979 * context: The context pointer passed to DNSServiceEnumerateDomains. 980 * 981 */ 982 983 typedef void (DNSSD_API *DNSServiceDomainEnumReply) 984 ( 985 DNSServiceRef sdRef, 986 DNSServiceFlags flags, 987 uint32_t interfaceIndex, 988 DNSServiceErrorType errorCode, 989 const char *replyDomain, 990 void *context 991 ); 992 993 994 /* DNSServiceEnumerateDomains() Parameters: 995 * 996 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 997 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 998 * and the enumeration operation will run indefinitely until the client 999 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1000 * 1001 * flags: Possible values are: 1002 * kDNSServiceFlagsBrowseDomains to enumerate domains recommended for browsing. 1003 * kDNSServiceFlagsRegistrationDomains to enumerate domains recommended 1004 * for registration. 1005 * 1006 * interfaceIndex: If non-zero, specifies the interface on which to look for domains. 1007 * (the index for a given interface is determined via the if_nametoindex() 1008 * family of calls.) Most applications will pass 0 to enumerate domains on 1009 * all interfaces. See "Constants for specifying an interface index" for more details. 1010 * 1011 * callBack: The function to be called when a domain is found or the call asynchronously 1012 * fails. 1013 * 1014 * context: An application context pointer which is passed to the callback function 1015 * (may be NULL). 1016 * 1017 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1018 * errors are delivered to the callback), otherwise returns an error code indicating 1019 * the error that occurred (the callback is not invoked and the DNSServiceRef 1020 * is not initialized). 1021 */ 1022 1023 DNSServiceErrorType DNSSD_API DNSServiceEnumerateDomains 1024 ( 1025 DNSServiceRef *sdRef, 1026 DNSServiceFlags flags, 1027 uint32_t interfaceIndex, 1028 DNSServiceDomainEnumReply callBack, 1029 void *context /* may be NULL */ 1030 ); 1031 1032 1033 /********************************************************************************************* 1034 * 1035 * Service Registration 1036 * 1037 *********************************************************************************************/ 1038 1039 /* Register a service that is discovered via Browse() and Resolve() calls. 1040 * 1041 * DNSServiceRegisterReply() Callback Parameters: 1042 * 1043 * sdRef: The DNSServiceRef initialized by DNSServiceRegister(). 1044 * 1045 * flags: When a name is successfully registered, the callback will be 1046 * invoked with the kDNSServiceFlagsAdd flag set. When Wide-Area 1047 * DNS-SD is in use, it is possible for a single service to get 1048 * more than one success callback (e.g. one in the "local" multicast 1049 * DNS domain, and another in a wide-area unicast DNS domain). 1050 * If a successfully-registered name later suffers a name conflict 1051 * or similar problem and has to be deregistered, the callback will 1052 * be invoked with the kDNSServiceFlagsAdd flag not set. The callback 1053 * is *not* invoked in the case where the caller explicitly terminates 1054 * the service registration by calling DNSServiceRefDeallocate(ref); 1055 * 1056 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1057 * indicate the failure that occurred (including name conflicts, 1058 * if the kDNSServiceFlagsNoAutoRename flag was used when registering.) 1059 * Other parameters are undefined if errorCode is nonzero. 1060 * 1061 * name: The service name registered (if the application did not specify a name in 1062 * DNSServiceRegister(), this indicates what name was automatically chosen). 1063 * 1064 * regtype: The type of service registered, as it was passed to the callout. 1065 * 1066 * domain: The domain on which the service was registered (if the application did not 1067 * specify a domain in DNSServiceRegister(), this indicates the default domain 1068 * on which the service was registered). 1069 * 1070 * context: The context pointer that was passed to the callout. 1071 * 1072 */ 1073 1074 typedef void (DNSSD_API *DNSServiceRegisterReply) 1075 ( 1076 DNSServiceRef sdRef, 1077 DNSServiceFlags flags, 1078 DNSServiceErrorType errorCode, 1079 const char *name, 1080 const char *regtype, 1081 const char *domain, 1082 void *context 1083 ); 1084 1085 1086 /* DNSServiceRegister() Parameters: 1087 * 1088 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 1089 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 1090 * and the registration will remain active indefinitely until the client 1091 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1092 * 1093 * interfaceIndex: If non-zero, specifies the interface on which to register the service 1094 * (the index for a given interface is determined via the if_nametoindex() 1095 * family of calls.) Most applications will pass 0 to register on all 1096 * available interfaces. See "Constants for specifying an interface index" for more details. 1097 * 1098 * flags: Indicates the renaming behavior on name conflict (most applications 1099 * will pass 0). See flag definitions above for details. 1100 * 1101 * name: If non-NULL, specifies the service name to be registered. 1102 * Most applications will not specify a name, in which case the computer 1103 * name is used (this name is communicated to the client via the callback). 1104 * If a name is specified, it must be 1-63 bytes of UTF-8 text. 1105 * If the name is longer than 63 bytes it will be automatically truncated 1106 * to a legal length, unless the NoAutoRename flag is set, 1107 * in which case kDNSServiceErr_BadParam will be returned. 1108 * 1109 * regtype: The service type followed by the protocol, separated by a dot 1110 * (e.g. "_ftp._tcp"). The service type must be an underscore, followed 1111 * by 1-15 characters, which may be letters, digits, or hyphens. 1112 * The transport protocol must be "_tcp" or "_udp". New service types 1113 * should be registered at <http://www.dns-sd.org/ServiceTypes.html>. 1114 * 1115 * Additional subtypes of the primary service type (where a service 1116 * type has defined subtypes) follow the primary service type in a 1117 * comma-separated list, with no additional spaces, e.g. 1118 * "_primarytype._tcp,_subtype1,_subtype2,_subtype3" 1119 * Subtypes provide a mechanism for filtered browsing: A client browsing 1120 * for "_primarytype._tcp" will discover all instances of this type; 1121 * a client browsing for "_primarytype._tcp,_subtype2" will discover only 1122 * those instances that were registered with "_subtype2" in their list of 1123 * registered subtypes. 1124 * 1125 * The subtype mechanism can be illustrated with some examples using the 1126 * dns-sd command-line tool: 1127 * 1128 * % dns-sd -R Simple _test._tcp "" 1001 & 1129 * % dns-sd -R Better _test._tcp,HasFeatureA "" 1002 & 1130 * % dns-sd -R Best _test._tcp,HasFeatureA,HasFeatureB "" 1003 & 1131 * 1132 * Now: 1133 * % dns-sd -B _test._tcp # will find all three services 1134 * % dns-sd -B _test._tcp,HasFeatureA # finds "Better" and "Best" 1135 * % dns-sd -B _test._tcp,HasFeatureB # finds only "Best" 1136 * 1137 * Subtype labels may be up to 63 bytes long, and may contain any eight- 1138 * bit byte values, including zero bytes. However, due to the nature of 1139 * using a C-string-based API, conventional DNS escaping must be used for 1140 * dots ('.'), commas (','), backslashes ('\') and zero bytes, as shown below: 1141 * 1142 * % dns-sd -R Test '_test._tcp,s\.one,s\,two,s\\three,s\000four' local 123 1143 * 1144 * When a service is registered, all the clients browsing for the registered 1145 * type ("regtype") will discover it. If the discovery should be 1146 * restricted to a smaller set of well known peers, the service can be 1147 * registered with additional data (group identifier) that is known 1148 * only to a smaller set of peers. The group identifier should follow primary 1149 * service type using a colon (":") as a delimeter. If subtypes are also present, 1150 * it should be given before the subtype as shown below. 1151 * 1152 * % dns-sd -R _test1 _http._tcp:mygroup1 local 1001 1153 * % dns-sd -R _test2 _http._tcp:mygroup2 local 1001 1154 * % dns-sd -R _test3 _http._tcp:mygroup3,HasFeatureA local 1001 1155 * 1156 * Now: 1157 * % dns-sd -B _http._tcp:"mygroup1" # will discover only test1 1158 * % dns-sd -B _http._tcp:"mygroup2" # will discover only test2 1159 * % dns-sd -B _http._tcp:"mygroup3",HasFeatureA # will discover only test3 1160 * 1161 * By specifying the group information, only the members of that group are 1162 * discovered. 1163 * 1164 * The group identifier itself is not sent in clear. Only a hash of the group 1165 * identifier is sent and the clients discover them anonymously. The group identifier 1166 * may be up to 256 bytes long and may contain any eight bit values except comma which 1167 * should be escaped. 1168 * 1169 * domain: If non-NULL, specifies the domain on which to advertise the service. 1170 * Most applications will not specify a domain, instead automatically 1171 * registering in the default domain(s). 1172 * 1173 * host: If non-NULL, specifies the SRV target host name. Most applications 1174 * will not specify a host, instead automatically using the machine's 1175 * default host name(s). Note that specifying a non-NULL host does NOT 1176 * create an address record for that host - the application is responsible 1177 * for ensuring that the appropriate address record exists, or creating it 1178 * via DNSServiceRegisterRecord(). 1179 * 1180 * port: The port, in network byte order, on which the service accepts connections. 1181 * Pass 0 for a "placeholder" service (i.e. a service that will not be discovered 1182 * by browsing, but will cause a name conflict if another client tries to 1183 * register that same name). Most clients will not use placeholder services. 1184 * 1185 * txtLen: The length of the txtRecord, in bytes. Must be zero if the txtRecord is NULL. 1186 * 1187 * txtRecord: The TXT record rdata. A non-NULL txtRecord MUST be a properly formatted DNS 1188 * TXT record, i.e. <length byte> <data> <length byte> <data> ... 1189 * Passing NULL for the txtRecord is allowed as a synonym for txtLen=1, txtRecord="", 1190 * i.e. it creates a TXT record of length one containing a single empty string. 1191 * RFC 1035 doesn't allow a TXT record to contain *zero* strings, so a single empty 1192 * string is the smallest legal DNS TXT record. 1193 * As with the other parameters, the DNSServiceRegister call copies the txtRecord 1194 * data; e.g. if you allocated the storage for the txtRecord parameter with malloc() 1195 * then you can safely free that memory right after the DNSServiceRegister call returns. 1196 * 1197 * callBack: The function to be called when the registration completes or asynchronously 1198 * fails. The client MAY pass NULL for the callback - The client will NOT be notified 1199 * of the default values picked on its behalf, and the client will NOT be notified of any 1200 * asynchronous errors (e.g. out of memory errors, etc.) that may prevent the registration 1201 * of the service. The client may NOT pass the NoAutoRename flag if the callback is NULL. 1202 * The client may still deregister the service at any time via DNSServiceRefDeallocate(). 1203 * 1204 * context: An application context pointer which is passed to the callback function 1205 * (may be NULL). 1206 * 1207 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1208 * errors are delivered to the callback), otherwise returns an error code indicating 1209 * the error that occurred (the callback is never invoked and the DNSServiceRef 1210 * is not initialized). 1211 */ 1212 1213 DNSServiceErrorType DNSSD_API DNSServiceRegister 1214 ( 1215 DNSServiceRef *sdRef, 1216 DNSServiceFlags flags, 1217 uint32_t interfaceIndex, 1218 const char *name, /* may be NULL */ 1219 const char *regtype, 1220 const char *domain, /* may be NULL */ 1221 const char *host, /* may be NULL */ 1222 uint16_t port, /* In network byte order */ 1223 uint16_t txtLen, 1224 const void *txtRecord, /* may be NULL */ 1225 DNSServiceRegisterReply callBack, /* may be NULL */ 1226 void *context /* may be NULL */ 1227 ); 1228 1229 1230 /* DNSServiceAddRecord() 1231 * 1232 * Add a record to a registered service. The name of the record will be the same as the 1233 * registered service's name. 1234 * The record can later be updated or deregistered by passing the RecordRef initialized 1235 * by this function to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 1236 * 1237 * Note that the DNSServiceAddRecord/UpdateRecord/RemoveRecord are *NOT* thread-safe 1238 * with respect to a single DNSServiceRef. If you plan to have multiple threads 1239 * in your program simultaneously add, update, or remove records from the same 1240 * DNSServiceRef, then it's the caller's responsibility to use a mutext lock 1241 * or take similar appropriate precautions to serialize those calls. 1242 * 1243 * Parameters; 1244 * 1245 * sdRef: A DNSServiceRef initialized by DNSServiceRegister(). 1246 * 1247 * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this 1248 * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 1249 * If the above DNSServiceRef is passed to DNSServiceRefDeallocate(), RecordRef is also 1250 * invalidated and may not be used further. 1251 * 1252 * flags: Currently ignored, reserved for future use. 1253 * 1254 * rrtype: The type of the record (e.g. kDNSServiceType_TXT, kDNSServiceType_SRV, etc) 1255 * 1256 * rdlen: The length, in bytes, of the rdata. 1257 * 1258 * rdata: The raw rdata to be contained in the added resource record. 1259 * 1260 * ttl: The time to live of the resource record, in seconds. 1261 * Most clients should pass 0 to indicate that the system should 1262 * select a sensible default value. 1263 * 1264 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 1265 * error code indicating the error that occurred (the RecordRef is not initialized). 1266 */ 1267 1268 DNSServiceErrorType DNSSD_API DNSServiceAddRecord 1269 ( 1270 DNSServiceRef sdRef, 1271 DNSRecordRef *RecordRef, 1272 DNSServiceFlags flags, 1273 uint16_t rrtype, 1274 uint16_t rdlen, 1275 const void *rdata, 1276 uint32_t ttl 1277 ); 1278 1279 1280 /* DNSServiceUpdateRecord 1281 * 1282 * Update a registered resource record. The record must either be: 1283 * - The primary txt record of a service registered via DNSServiceRegister() 1284 * - A record added to a registered service via DNSServiceAddRecord() 1285 * - An individual record registered by DNSServiceRegisterRecord() 1286 * 1287 * Parameters: 1288 * 1289 * sdRef: A DNSServiceRef that was initialized by DNSServiceRegister() 1290 * or DNSServiceCreateConnection(). 1291 * 1292 * RecordRef: A DNSRecordRef initialized by DNSServiceAddRecord, or NULL to update the 1293 * service's primary txt record. 1294 * 1295 * flags: Currently ignored, reserved for future use. 1296 * 1297 * rdlen: The length, in bytes, of the new rdata. 1298 * 1299 * rdata: The new rdata to be contained in the updated resource record. 1300 * 1301 * ttl: The time to live of the updated resource record, in seconds. 1302 * Most clients should pass 0 to indicate that the system should 1303 * select a sensible default value. 1304 * 1305 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 1306 * error code indicating the error that occurred. 1307 */ 1308 1309 DNSServiceErrorType DNSSD_API DNSServiceUpdateRecord 1310 ( 1311 DNSServiceRef sdRef, 1312 DNSRecordRef RecordRef, /* may be NULL */ 1313 DNSServiceFlags flags, 1314 uint16_t rdlen, 1315 const void *rdata, 1316 uint32_t ttl 1317 ); 1318 1319 1320 /* DNSServiceRemoveRecord 1321 * 1322 * Remove a record previously added to a service record set via DNSServiceAddRecord(), or deregister 1323 * an record registered individually via DNSServiceRegisterRecord(). 1324 * 1325 * Parameters: 1326 * 1327 * sdRef: A DNSServiceRef initialized by DNSServiceRegister() (if the 1328 * record being removed was registered via DNSServiceAddRecord()) or by 1329 * DNSServiceCreateConnection() (if the record being removed was registered via 1330 * DNSServiceRegisterRecord()). 1331 * 1332 * recordRef: A DNSRecordRef initialized by a successful call to DNSServiceAddRecord() 1333 * or DNSServiceRegisterRecord(). 1334 * 1335 * flags: Currently ignored, reserved for future use. 1336 * 1337 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an 1338 * error code indicating the error that occurred. 1339 */ 1340 1341 DNSServiceErrorType DNSSD_API DNSServiceRemoveRecord 1342 ( 1343 DNSServiceRef sdRef, 1344 DNSRecordRef RecordRef, 1345 DNSServiceFlags flags 1346 ); 1347 1348 1349 /********************************************************************************************* 1350 * 1351 * Service Discovery 1352 * 1353 *********************************************************************************************/ 1354 1355 /* Browse for instances of a service. 1356 * 1357 * DNSServiceBrowseReply() Parameters: 1358 * 1359 * sdRef: The DNSServiceRef initialized by DNSServiceBrowse(). 1360 * 1361 * flags: Possible values are kDNSServiceFlagsMoreComing and kDNSServiceFlagsAdd. 1362 * See flag definitions for details. 1363 * 1364 * interfaceIndex: The interface on which the service is advertised. This index should 1365 * be passed to DNSServiceResolve() when resolving the service. 1366 * 1367 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will 1368 * indicate the failure that occurred. Other parameters are undefined if 1369 * the errorCode is nonzero. 1370 * 1371 * serviceName: The discovered service name. This name should be displayed to the user, 1372 * and stored for subsequent use in the DNSServiceResolve() call. 1373 * 1374 * regtype: The service type, which is usually (but not always) the same as was passed 1375 * to DNSServiceBrowse(). One case where the discovered service type may 1376 * not be the same as the requested service type is when using subtypes: 1377 * The client may want to browse for only those ftp servers that allow 1378 * anonymous connections. The client will pass the string "_ftp._tcp,_anon" 1379 * to DNSServiceBrowse(), but the type of the service that's discovered 1380 * is simply "_ftp._tcp". The regtype for each discovered service instance 1381 * should be stored along with the name, so that it can be passed to 1382 * DNSServiceResolve() when the service is later resolved. 1383 * 1384 * domain: The domain of the discovered service instance. This may or may not be the 1385 * same as the domain that was passed to DNSServiceBrowse(). The domain for each 1386 * discovered service instance should be stored along with the name, so that 1387 * it can be passed to DNSServiceResolve() when the service is later resolved. 1388 * 1389 * context: The context pointer that was passed to the callout. 1390 * 1391 */ 1392 1393 typedef void (DNSSD_API *DNSServiceBrowseReply) 1394 ( 1395 DNSServiceRef sdRef, 1396 DNSServiceFlags flags, 1397 uint32_t interfaceIndex, 1398 DNSServiceErrorType errorCode, 1399 const char *serviceName, 1400 const char *regtype, 1401 const char *replyDomain, 1402 void *context 1403 ); 1404 1405 1406 /* DNSServiceBrowse() Parameters: 1407 * 1408 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 1409 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 1410 * and the browse operation will run indefinitely until the client 1411 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1412 * 1413 * flags: Currently ignored, reserved for future use. 1414 * 1415 * interfaceIndex: If non-zero, specifies the interface on which to browse for services 1416 * (the index for a given interface is determined via the if_nametoindex() 1417 * family of calls.) Most applications will pass 0 to browse on all available 1418 * interfaces. See "Constants for specifying an interface index" for more details. 1419 * 1420 * regtype: The service type being browsed for followed by the protocol, separated by a 1421 * dot (e.g. "_ftp._tcp"). The transport protocol must be "_tcp" or "_udp". 1422 * A client may optionally specify a single subtype to perform filtered browsing: 1423 * e.g. browsing for "_primarytype._tcp,_subtype" will discover only those 1424 * instances of "_primarytype._tcp" that were registered specifying "_subtype" 1425 * in their list of registered subtypes. Additionally, a group identifier may 1426 * also be specified before the subtype e.g., _primarytype._tcp:GroupID, which 1427 * will discover only the members that register the service with GroupID. See 1428 * DNSServiceRegister for more details. 1429 * 1430 * domain: If non-NULL, specifies the domain on which to browse for services. 1431 * Most applications will not specify a domain, instead browsing on the 1432 * default domain(s). 1433 * 1434 * callBack: The function to be called when an instance of the service being browsed for 1435 * is found, or if the call asynchronously fails. 1436 * 1437 * context: An application context pointer which is passed to the callback function 1438 * (may be NULL). 1439 * 1440 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1441 * errors are delivered to the callback), otherwise returns an error code indicating 1442 * the error that occurred (the callback is not invoked and the DNSServiceRef 1443 * is not initialized). 1444 */ 1445 1446 DNSServiceErrorType DNSSD_API DNSServiceBrowse 1447 ( 1448 DNSServiceRef *sdRef, 1449 DNSServiceFlags flags, 1450 uint32_t interfaceIndex, 1451 const char *regtype, 1452 const char *domain, /* may be NULL */ 1453 DNSServiceBrowseReply callBack, 1454 void *context /* may be NULL */ 1455 ); 1456 1457 1458 /* DNSServiceResolve() 1459 * 1460 * Resolve a service name discovered via DNSServiceBrowse() to a target host name, port number, and 1461 * txt record. 1462 * 1463 * Note: Applications should NOT use DNSServiceResolve() solely for txt record monitoring - use 1464 * DNSServiceQueryRecord() instead, as it is more efficient for this task. 1465 * 1466 * Note: When the desired results have been returned, the client MUST terminate the resolve by calling 1467 * DNSServiceRefDeallocate(). 1468 * 1469 * Note: DNSServiceResolve() behaves correctly for typical services that have a single SRV record 1470 * and a single TXT record. To resolve non-standard services with multiple SRV or TXT records, 1471 * DNSServiceQueryRecord() should be used. 1472 * 1473 * DNSServiceResolveReply Callback Parameters: 1474 * 1475 * sdRef: The DNSServiceRef initialized by DNSServiceResolve(). 1476 * 1477 * flags: Possible values: kDNSServiceFlagsMoreComing 1478 * 1479 * interfaceIndex: The interface on which the service was resolved. 1480 * 1481 * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will 1482 * indicate the failure that occurred. Other parameters are undefined if 1483 * the errorCode is nonzero. 1484 * 1485 * fullname: The full service domain name, in the form <servicename>.<protocol>.<domain>. 1486 * (This name is escaped following standard DNS rules, making it suitable for 1487 * passing to standard system DNS APIs such as res_query(), or to the 1488 * special-purpose functions included in this API that take fullname parameters. 1489 * See "Notes on DNS Name Escaping" earlier in this file for more details.) 1490 * 1491 * hosttarget: The target hostname of the machine providing the service. This name can 1492 * be passed to functions like gethostbyname() to identify the host's IP address. 1493 * 1494 * port: The port, in network byte order, on which connections are accepted for this service. 1495 * 1496 * txtLen: The length of the txt record, in bytes. 1497 * 1498 * txtRecord: The service's primary txt record, in standard txt record format. 1499 * 1500 * context: The context pointer that was passed to the callout. 1501 * 1502 * NOTE: In earlier versions of this header file, the txtRecord parameter was declared "const char *" 1503 * This is incorrect, since it contains length bytes which are values in the range 0 to 255, not -128 to +127. 1504 * Depending on your compiler settings, this change may cause signed/unsigned mismatch warnings. 1505 * These should be fixed by updating your own callback function definition to match the corrected 1506 * function signature using "const unsigned char *txtRecord". Making this change may also fix inadvertent 1507 * bugs in your callback function, where it could have incorrectly interpreted a length byte with value 250 1508 * as being -6 instead, with various bad consequences ranging from incorrect operation to software crashes. 1509 * If you need to maintain portable code that will compile cleanly with both the old and new versions of 1510 * this header file, you should update your callback function definition to use the correct unsigned value, 1511 * and then in the place where you pass your callback function to DNSServiceResolve(), use a cast to eliminate 1512 * the compiler warning, e.g.: 1513 * DNSServiceResolve(sd, flags, index, name, regtype, domain, (DNSServiceResolveReply)MyCallback, context); 1514 * This will ensure that your code compiles cleanly without warnings (and more importantly, works correctly) 1515 * with both the old header and with the new corrected version. 1516 * 1517 */ 1518 1519 typedef void (DNSSD_API *DNSServiceResolveReply) 1520 ( 1521 DNSServiceRef sdRef, 1522 DNSServiceFlags flags, 1523 uint32_t interfaceIndex, 1524 DNSServiceErrorType errorCode, 1525 const char *fullname, 1526 const char *hosttarget, 1527 uint16_t port, /* In network byte order */ 1528 uint16_t txtLen, 1529 const unsigned char *txtRecord, 1530 void *context 1531 ); 1532 1533 1534 /* DNSServiceResolve() Parameters 1535 * 1536 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 1537 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 1538 * and the resolve operation will run indefinitely until the client 1539 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1540 * 1541 * flags: Specifying kDNSServiceFlagsForceMulticast will cause query to be 1542 * performed with a link-local mDNS query, even if the name is an 1543 * apparently non-local name (i.e. a name not ending in ".local.") 1544 * 1545 * interfaceIndex: The interface on which to resolve the service. If this resolve call is 1546 * as a result of a currently active DNSServiceBrowse() operation, then the 1547 * interfaceIndex should be the index reported in the DNSServiceBrowseReply 1548 * callback. If this resolve call is using information previously saved 1549 * (e.g. in a preference file) for later use, then use interfaceIndex 0, because 1550 * the desired service may now be reachable via a different physical interface. 1551 * See "Constants for specifying an interface index" for more details. 1552 * 1553 * name: The name of the service instance to be resolved, as reported to the 1554 * DNSServiceBrowseReply() callback. 1555 * 1556 * regtype: The type of the service instance to be resolved, as reported to the 1557 * DNSServiceBrowseReply() callback. 1558 * 1559 * domain: The domain of the service instance to be resolved, as reported to the 1560 * DNSServiceBrowseReply() callback. 1561 * 1562 * callBack: The function to be called when a result is found, or if the call 1563 * asynchronously fails. 1564 * 1565 * context: An application context pointer which is passed to the callback function 1566 * (may be NULL). 1567 * 1568 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1569 * errors are delivered to the callback), otherwise returns an error code indicating 1570 * the error that occurred (the callback is never invoked and the DNSServiceRef 1571 * is not initialized). 1572 */ 1573 1574 DNSServiceErrorType DNSSD_API DNSServiceResolve 1575 ( 1576 DNSServiceRef *sdRef, 1577 DNSServiceFlags flags, 1578 uint32_t interfaceIndex, 1579 const char *name, 1580 const char *regtype, 1581 const char *domain, 1582 DNSServiceResolveReply callBack, 1583 void *context /* may be NULL */ 1584 ); 1585 1586 1587 /********************************************************************************************* 1588 * 1589 * Querying Individual Specific Records 1590 * 1591 *********************************************************************************************/ 1592 1593 /* DNSServiceQueryRecord 1594 * 1595 * Query for an arbitrary DNS record. 1596 * 1597 * DNSServiceQueryRecordReply() Callback Parameters: 1598 * 1599 * sdRef: The DNSServiceRef initialized by DNSServiceQueryRecord(). 1600 * 1601 * flags: Possible values are kDNSServiceFlagsMoreComing and 1602 * kDNSServiceFlagsAdd. The Add flag is NOT set for PTR records 1603 * with a ttl of 0, i.e. "Remove" events. 1604 * 1605 * interfaceIndex: The interface on which the query was resolved (the index for a given 1606 * interface is determined via the if_nametoindex() family of calls). 1607 * See "Constants for specifying an interface index" for more details. 1608 * 1609 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1610 * indicate the failure that occurred. Other parameters are undefined if 1611 * errorCode is nonzero. 1612 * 1613 * fullname: The resource record's full domain name. 1614 * 1615 * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1616 * 1617 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1618 * 1619 * rdlen: The length, in bytes, of the resource record rdata. 1620 * 1621 * rdata: The raw rdata of the resource record. 1622 * 1623 * ttl: If the client wishes to cache the result for performance reasons, 1624 * the TTL indicates how long the client may legitimately hold onto 1625 * this result, in seconds. After the TTL expires, the client should 1626 * consider the result no longer valid, and if it requires this data 1627 * again, it should be re-fetched with a new query. Of course, this 1628 * only applies to clients that cancel the asynchronous operation when 1629 * they get a result. Clients that leave the asynchronous operation 1630 * running can safely assume that the data remains valid until they 1631 * get another callback telling them otherwise. 1632 * 1633 * context: The context pointer that was passed to the callout. 1634 * 1635 */ 1636 1637 typedef void (DNSSD_API *DNSServiceQueryRecordReply) 1638 ( 1639 DNSServiceRef sdRef, 1640 DNSServiceFlags flags, 1641 uint32_t interfaceIndex, 1642 DNSServiceErrorType errorCode, 1643 const char *fullname, 1644 uint16_t rrtype, 1645 uint16_t rrclass, 1646 uint16_t rdlen, 1647 const void *rdata, 1648 uint32_t ttl, 1649 void *context 1650 ); 1651 1652 1653 /* DNSServiceQueryRecord() Parameters: 1654 * 1655 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds 1656 * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, 1657 * and the query operation will run indefinitely until the client 1658 * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1659 * 1660 * flags: kDNSServiceFlagsForceMulticast or kDNSServiceFlagsLongLivedQuery. 1661 * Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast 1662 * query to a unicast DNS server that implements the protocol. This flag 1663 * has no effect on link-local multicast queries. 1664 * 1665 * interfaceIndex: If non-zero, specifies the interface on which to issue the query 1666 * (the index for a given interface is determined via the if_nametoindex() 1667 * family of calls.) Passing 0 causes the name to be queried for on all 1668 * interfaces. See "Constants for specifying an interface index" for more details. 1669 * 1670 * fullname: The full domain name of the resource record to be queried for. 1671 * 1672 * rrtype: The numerical type of the resource record to be queried for 1673 * (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1674 * 1675 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1676 * 1677 * callBack: The function to be called when a result is found, or if the call 1678 * asynchronously fails. 1679 * 1680 * context: An application context pointer which is passed to the callback function 1681 * (may be NULL). 1682 * 1683 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1684 * errors are delivered to the callback), otherwise returns an error code indicating 1685 * the error that occurred (the callback is never invoked and the DNSServiceRef 1686 * is not initialized). 1687 */ 1688 1689 DNSServiceErrorType DNSSD_API DNSServiceQueryRecord 1690 ( 1691 DNSServiceRef *sdRef, 1692 DNSServiceFlags flags, 1693 uint32_t interfaceIndex, 1694 const char *fullname, 1695 uint16_t rrtype, 1696 uint16_t rrclass, 1697 DNSServiceQueryRecordReply callBack, 1698 void *context /* may be NULL */ 1699 ); 1700 1701 1702 /********************************************************************************************* 1703 * 1704 * Unified lookup of both IPv4 and IPv6 addresses for a fully qualified hostname 1705 * 1706 *********************************************************************************************/ 1707 1708 /* DNSServiceGetAddrInfo 1709 * 1710 * Queries for the IP address of a hostname by using either Multicast or Unicast DNS. 1711 * 1712 * DNSServiceGetAddrInfoReply() parameters: 1713 * 1714 * sdRef: The DNSServiceRef initialized by DNSServiceGetAddrInfo(). 1715 * 1716 * flags: Possible values are kDNSServiceFlagsMoreComing and 1717 * kDNSServiceFlagsAdd. 1718 * 1719 * interfaceIndex: The interface to which the answers pertain. 1720 * 1721 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1722 * indicate the failure that occurred. Other parameters are 1723 * undefined if errorCode is nonzero. 1724 * 1725 * hostname: The fully qualified domain name of the host to be queried for. 1726 * 1727 * address: IPv4 or IPv6 address. 1728 * 1729 * ttl: If the client wishes to cache the result for performance reasons, 1730 * the TTL indicates how long the client may legitimately hold onto 1731 * this result, in seconds. After the TTL expires, the client should 1732 * consider the result no longer valid, and if it requires this data 1733 * again, it should be re-fetched with a new query. Of course, this 1734 * only applies to clients that cancel the asynchronous operation when 1735 * they get a result. Clients that leave the asynchronous operation 1736 * running can safely assume that the data remains valid until they 1737 * get another callback telling them otherwise. 1738 * 1739 * context: The context pointer that was passed to the callout. 1740 * 1741 */ 1742 1743 typedef void (DNSSD_API *DNSServiceGetAddrInfoReply) 1744 ( 1745 DNSServiceRef sdRef, 1746 DNSServiceFlags flags, 1747 uint32_t interfaceIndex, 1748 DNSServiceErrorType errorCode, 1749 const char *hostname, 1750 const struct sockaddr *address, 1751 uint32_t ttl, 1752 void *context 1753 ); 1754 1755 1756 /* DNSServiceGetAddrInfo() Parameters: 1757 * 1758 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds then it 1759 * initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the query 1760 * begins and will last indefinitely until the client terminates the query 1761 * by passing this DNSServiceRef to DNSServiceRefDeallocate(). 1762 * 1763 * flags: kDNSServiceFlagsForceMulticast 1764 * 1765 * interfaceIndex: The interface on which to issue the query. Passing 0 causes the query to be 1766 * sent on all active interfaces via Multicast or the primary interface via Unicast. 1767 * 1768 * protocol: Pass in kDNSServiceProtocol_IPv4 to look up IPv4 addresses, or kDNSServiceProtocol_IPv6 1769 * to look up IPv6 addresses, or both to look up both kinds. If neither flag is 1770 * set, the system will apply an intelligent heuristic, which is (currently) 1771 * that it will attempt to look up both, except: 1772 * 1773 * * If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name) 1774 * but this host has no routable IPv6 address, then the call will not try to 1775 * look up IPv6 addresses for "hostname", since any addresses it found would be 1776 * unlikely to be of any use anyway. Similarly, if this host has no routable 1777 * IPv4 address, the call will not try to look up IPv4 addresses for "hostname". 1778 * 1779 * hostname: The fully qualified domain name of the host to be queried for. 1780 * 1781 * callBack: The function to be called when the query succeeds or fails asynchronously. 1782 * 1783 * context: An application context pointer which is passed to the callback function 1784 * (may be NULL). 1785 * 1786 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1787 * errors are delivered to the callback), otherwise returns an error code indicating 1788 * the error that occurred. 1789 */ 1790 1791 DNSServiceErrorType DNSSD_API DNSServiceGetAddrInfo 1792 ( 1793 DNSServiceRef *sdRef, 1794 DNSServiceFlags flags, 1795 uint32_t interfaceIndex, 1796 DNSServiceProtocol protocol, 1797 const char *hostname, 1798 DNSServiceGetAddrInfoReply callBack, 1799 void *context /* may be NULL */ 1800 ); 1801 1802 1803 /********************************************************************************************* 1804 * 1805 * Special Purpose Calls: 1806 * DNSServiceCreateConnection(), DNSServiceRegisterRecord(), DNSServiceReconfirmRecord() 1807 * (most applications will not use these) 1808 * 1809 *********************************************************************************************/ 1810 1811 /* DNSServiceCreateConnection() 1812 * 1813 * Create a connection to the daemon allowing efficient registration of 1814 * multiple individual records. 1815 * 1816 * Parameters: 1817 * 1818 * sdRef: A pointer to an uninitialized DNSServiceRef. Deallocating 1819 * the reference (via DNSServiceRefDeallocate()) severs the 1820 * connection and deregisters all records registered on this connection. 1821 * 1822 * return value: Returns kDNSServiceErr_NoError on success, otherwise returns 1823 * an error code indicating the specific failure that occurred (in which 1824 * case the DNSServiceRef is not initialized). 1825 */ 1826 1827 DNSServiceErrorType DNSSD_API DNSServiceCreateConnection(DNSServiceRef *sdRef); 1828 1829 /* DNSServiceRegisterRecord 1830 * 1831 * Register an individual resource record on a connected DNSServiceRef. 1832 * 1833 * Note that name conflicts occurring for records registered via this call must be handled 1834 * by the client in the callback. 1835 * 1836 * DNSServiceRegisterRecordReply() parameters: 1837 * 1838 * sdRef: The connected DNSServiceRef initialized by 1839 * DNSServiceCreateConnection(). 1840 * 1841 * RecordRef: The DNSRecordRef initialized by DNSServiceRegisterRecord(). If the above 1842 * DNSServiceRef is passed to DNSServiceRefDeallocate(), this DNSRecordRef is 1843 * invalidated, and may not be used further. 1844 * 1845 * flags: Currently unused, reserved for future use. 1846 * 1847 * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will 1848 * indicate the failure that occurred (including name conflicts.) 1849 * Other parameters are undefined if errorCode is nonzero. 1850 * 1851 * context: The context pointer that was passed to the callout. 1852 * 1853 */ 1854 1855 typedef void (DNSSD_API *DNSServiceRegisterRecordReply) 1856 ( 1857 DNSServiceRef sdRef, 1858 DNSRecordRef RecordRef, 1859 DNSServiceFlags flags, 1860 DNSServiceErrorType errorCode, 1861 void *context 1862 ); 1863 1864 1865 /* DNSServiceRegisterRecord() Parameters: 1866 * 1867 * sdRef: A DNSServiceRef initialized by DNSServiceCreateConnection(). 1868 * 1869 * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this 1870 * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). 1871 * (To deregister ALL records registered on a single connected DNSServiceRef 1872 * and deallocate each of their corresponding DNSServiceRecordRefs, call 1873 * DNSServiceRefDeallocate()). 1874 * 1875 * flags: Possible values are kDNSServiceFlagsShared or kDNSServiceFlagsUnique 1876 * (see flag type definitions for details). 1877 * 1878 * interfaceIndex: If non-zero, specifies the interface on which to register the record 1879 * (the index for a given interface is determined via the if_nametoindex() 1880 * family of calls.) Passing 0 causes the record to be registered on all interfaces. 1881 * See "Constants for specifying an interface index" for more details. 1882 * 1883 * fullname: The full domain name of the resource record. 1884 * 1885 * rrtype: The numerical type of the resource record (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1886 * 1887 * rrclass: The class of the resource record (usually kDNSServiceClass_IN) 1888 * 1889 * rdlen: Length, in bytes, of the rdata. 1890 * 1891 * rdata: A pointer to the raw rdata, as it is to appear in the DNS record. 1892 * 1893 * ttl: The time to live of the resource record, in seconds. 1894 * Most clients should pass 0 to indicate that the system should 1895 * select a sensible default value. 1896 * 1897 * callBack: The function to be called when a result is found, or if the call 1898 * asynchronously fails (e.g. because of a name conflict.) 1899 * 1900 * context: An application context pointer which is passed to the callback function 1901 * (may be NULL). 1902 * 1903 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 1904 * errors are delivered to the callback), otherwise returns an error code indicating 1905 * the error that occurred (the callback is never invoked and the DNSRecordRef is 1906 * not initialized). 1907 */ 1908 1909 DNSServiceErrorType DNSSD_API DNSServiceRegisterRecord 1910 ( 1911 DNSServiceRef sdRef, 1912 DNSRecordRef *RecordRef, 1913 DNSServiceFlags flags, 1914 uint32_t interfaceIndex, 1915 const char *fullname, 1916 uint16_t rrtype, 1917 uint16_t rrclass, 1918 uint16_t rdlen, 1919 const void *rdata, 1920 uint32_t ttl, 1921 DNSServiceRegisterRecordReply callBack, 1922 void *context /* may be NULL */ 1923 ); 1924 1925 1926 /* DNSServiceReconfirmRecord 1927 * 1928 * Instruct the daemon to verify the validity of a resource record that appears 1929 * to be out of date (e.g. because TCP connection to a service's target failed.) 1930 * Causes the record to be flushed from the daemon's cache (as well as all other 1931 * daemons' caches on the network) if the record is determined to be invalid. 1932 * Use this routine conservatively. Reconfirming a record necessarily consumes 1933 * network bandwidth, so this should not be done indiscriminately. 1934 * 1935 * Parameters: 1936 * 1937 * flags: Not currently used. 1938 * 1939 * interfaceIndex: Specifies the interface of the record in question. 1940 * The caller must specify the interface. 1941 * This API (by design) causes increased network traffic, so it requires 1942 * the caller to be precise about which record should be reconfirmed. 1943 * It is not possible to pass zero for the interface index to perform 1944 * a "wildcard" reconfirmation, where *all* matching records are reconfirmed. 1945 * 1946 * fullname: The resource record's full domain name. 1947 * 1948 * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) 1949 * 1950 * rrclass: The class of the resource record (usually kDNSServiceClass_IN). 1951 * 1952 * rdlen: The length, in bytes, of the resource record rdata. 1953 * 1954 * rdata: The raw rdata of the resource record. 1955 * 1956 */ 1957 1958 DNSServiceErrorType DNSSD_API DNSServiceReconfirmRecord 1959 ( 1960 DNSServiceFlags flags, 1961 uint32_t interfaceIndex, 1962 const char *fullname, 1963 uint16_t rrtype, 1964 uint16_t rrclass, 1965 uint16_t rdlen, 1966 const void *rdata 1967 ); 1968 1969 1970 /********************************************************************************************* 1971 * 1972 * NAT Port Mapping 1973 * 1974 *********************************************************************************************/ 1975 1976 /* DNSServiceNATPortMappingCreate 1977 * 1978 * Request a port mapping in the NAT gateway, which maps a port on the local machine 1979 * to an external port on the NAT. The NAT should support either PCP, NAT-PMP or the 1980 * UPnP/IGD protocol for this API to create a successful mapping. Note that this API 1981 * currently supports IPv4 addresses/mappings only. If the NAT gateway supports PCP and 1982 * returns an IPv6 address (incorrectly, since this API specifically requests IPv4 1983 * addresses), the DNSServiceNATPortMappingReply callback will be invoked with errorCode 1984 * kDNSServiceErr_NATPortMappingUnsupported. 1985 * 1986 * The port mapping will be renewed indefinitely until the client process exits, or 1987 * explicitly terminates the port mapping request by calling DNSServiceRefDeallocate(). 1988 * The client callback will be invoked, informing the client of the NAT gateway's 1989 * external IP address and the external port that has been allocated for this client. 1990 * The client should then record this external IP address and port using whatever 1991 * directory service mechanism it is using to enable peers to connect to it. 1992 * (Clients advertising services using Wide-Area DNS-SD DO NOT need to use this API 1993 * -- when a client calls DNSServiceRegister() NAT mappings are automatically created 1994 * and the external IP address and port for the service are recorded in the global DNS. 1995 * Only clients using some directory mechanism other than Wide-Area DNS-SD need to use 1996 * this API to explicitly map their own ports.) 1997 * 1998 * It's possible that the client callback could be called multiple times, for example 1999 * if the NAT gateway's IP address changes, or if a configuration change results in a 2000 * different external port being mapped for this client. Over the lifetime of any long-lived 2001 * port mapping, the client should be prepared to handle these notifications of changes 2002 * in the environment, and should update its recorded address and/or port as appropriate. 2003 * 2004 * NOTE: There are two unusual aspects of how the DNSServiceNATPortMappingCreate API works, 2005 * which were intentionally designed to help simplify client code: 2006 * 2007 * 1. It's not an error to request a NAT mapping when the machine is not behind a NAT gateway. 2008 * In other NAT mapping APIs, if you request a NAT mapping and the machine is not behind a NAT 2009 * gateway, then the API returns an error code -- it can't get you a NAT mapping if there's no 2010 * NAT gateway. The DNSServiceNATPortMappingCreate API takes a different view. Working out 2011 * whether or not you need a NAT mapping can be tricky and non-obvious, particularly on 2012 * a machine with multiple active network interfaces. Rather than make every client recreate 2013 * this logic for deciding whether a NAT mapping is required, the PortMapping API does that 2014 * work for you. If the client calls the PortMapping API when the machine already has a 2015 * routable public IP address, then instead of complaining about it and giving an error, 2016 * the PortMapping API just invokes your callback, giving the machine's public address 2017 * and your own port number. This means you don't need to write code to work out whether 2018 * your client needs to call the PortMapping API -- just call it anyway, and if it wasn't 2019 * necessary, no harm is done: 2020 * 2021 * - If the machine already has a routable public IP address, then your callback 2022 * will just be invoked giving your own address and port. 2023 * - If a NAT mapping is required and obtained, then your callback will be invoked 2024 * giving you the external address and port. 2025 * - If a NAT mapping is required but not obtained from the local NAT gateway, 2026 * or the machine has no network connectivity, then your callback will be 2027 * invoked giving zero address and port. 2028 * 2029 * 2. In other NAT mapping APIs, if a laptop computer is put to sleep and woken up on a new 2030 * network, it's the client's job to notice this, and work out whether a NAT mapping 2031 * is required on the new network, and make a new NAT mapping request if necessary. 2032 * The DNSServiceNATPortMappingCreate API does this for you, automatically. 2033 * The client just needs to make one call to the PortMapping API, and its callback will 2034 * be invoked any time the mapping state changes. This property complements point (1) above. 2035 * If the client didn't make a NAT mapping request just because it determined that one was 2036 * not required at that particular moment in time, the client would then have to monitor 2037 * for network state changes to determine if a NAT port mapping later became necessary. 2038 * By unconditionally making a NAT mapping request, even when a NAT mapping not to be 2039 * necessary, the PortMapping API will then begin monitoring network state changes on behalf of 2040 * the client, and if a NAT mapping later becomes necessary, it will automatically create a NAT 2041 * mapping and inform the client with a new callback giving the new address and port information. 2042 * 2043 * DNSServiceNATPortMappingReply() parameters: 2044 * 2045 * sdRef: The DNSServiceRef initialized by DNSServiceNATPortMappingCreate(). 2046 * 2047 * flags: Currently unused, reserved for future use. 2048 * 2049 * interfaceIndex: The interface through which the NAT gateway is reached. 2050 * 2051 * errorCode: Will be kDNSServiceErr_NoError on success. 2052 * Will be kDNSServiceErr_DoubleNAT when the NAT gateway is itself behind one or 2053 * more layers of NAT, in which case the other parameters have the defined values. 2054 * For other failures, will indicate the failure that occurred, and the other 2055 * parameters are undefined. 2056 * 2057 * externalAddress: Four byte IPv4 address in network byte order. 2058 * 2059 * protocol: Will be kDNSServiceProtocol_UDP or kDNSServiceProtocol_TCP or both. 2060 * 2061 * internalPort: The port on the local machine that was mapped. 2062 * 2063 * externalPort: The actual external port in the NAT gateway that was mapped. 2064 * This is likely to be different than the requested external port. 2065 * 2066 * ttl: The lifetime of the NAT port mapping created on the gateway. 2067 * This controls how quickly stale mappings will be garbage-collected 2068 * if the client machine crashes, suffers a power failure, is disconnected 2069 * from the network, or suffers some other unfortunate demise which 2070 * causes it to vanish without explicitly removing its NAT port mapping. 2071 * It's possible that the ttl value will differ from the requested ttl value. 2072 * 2073 * context: The context pointer that was passed to the callout. 2074 * 2075 */ 2076 2077 typedef void (DNSSD_API *DNSServiceNATPortMappingReply) 2078 ( 2079 DNSServiceRef sdRef, 2080 DNSServiceFlags flags, 2081 uint32_t interfaceIndex, 2082 DNSServiceErrorType errorCode, 2083 uint32_t externalAddress, /* four byte IPv4 address in network byte order */ 2084 DNSServiceProtocol protocol, 2085 uint16_t internalPort, /* In network byte order */ 2086 uint16_t externalPort, /* In network byte order and may be different than the requested port */ 2087 uint32_t ttl, /* may be different than the requested ttl */ 2088 void *context 2089 ); 2090 2091 2092 /* DNSServiceNATPortMappingCreate() Parameters: 2093 * 2094 * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds then it 2095 * initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the nat 2096 * port mapping will last indefinitely until the client terminates the port 2097 * mapping request by passing this DNSServiceRef to DNSServiceRefDeallocate(). 2098 * 2099 * flags: Currently ignored, reserved for future use. 2100 * 2101 * interfaceIndex: The interface on which to create port mappings in a NAT gateway. Passing 0 causes 2102 * the port mapping request to be sent on the primary interface. 2103 * 2104 * protocol: To request a port mapping, pass in kDNSServiceProtocol_UDP, or kDNSServiceProtocol_TCP, 2105 * or (kDNSServiceProtocol_UDP | kDNSServiceProtocol_TCP) to map both. 2106 * The local listening port number must also be specified in the internalPort parameter. 2107 * To just discover the NAT gateway's external IP address, pass zero for protocol, 2108 * internalPort, externalPort and ttl. 2109 * 2110 * internalPort: The port number in network byte order on the local machine which is listening for packets. 2111 * 2112 * externalPort: The requested external port in network byte order in the NAT gateway that you would 2113 * like to map to the internal port. Pass 0 if you don't care which external port is chosen for you. 2114 * 2115 * ttl: The requested renewal period of the NAT port mapping, in seconds. 2116 * If the client machine crashes, suffers a power failure, is disconnected from 2117 * the network, or suffers some other unfortunate demise which causes it to vanish 2118 * unexpectedly without explicitly removing its NAT port mappings, then the NAT gateway 2119 * will garbage-collect old stale NAT port mappings when their lifetime expires. 2120 * Requesting a short TTL causes such orphaned mappings to be garbage-collected 2121 * more promptly, but consumes system resources and network bandwidth with 2122 * frequent renewal packets to keep the mapping from expiring. 2123 * Requesting a long TTL is more efficient on the network, but in the event of the 2124 * client vanishing, stale NAT port mappings will not be garbage-collected as quickly. 2125 * Most clients should pass 0 to use a system-wide default value. 2126 * 2127 * callBack: The function to be called when the port mapping request succeeds or fails asynchronously. 2128 * 2129 * context: An application context pointer which is passed to the callback function 2130 * (may be NULL). 2131 * 2132 * return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous 2133 * errors are delivered to the callback), otherwise returns an error code indicating 2134 * the error that occurred. 2135 * 2136 * If you don't actually want a port mapped, and are just calling the API 2137 * because you want to find out the NAT's external IP address (e.g. for UI 2138 * display) then pass zero for protocol, internalPort, externalPort and ttl. 2139 */ 2140 2141 DNSServiceErrorType DNSSD_API DNSServiceNATPortMappingCreate 2142 ( 2143 DNSServiceRef *sdRef, 2144 DNSServiceFlags flags, 2145 uint32_t interfaceIndex, 2146 DNSServiceProtocol protocol, /* TCP and/or UDP */ 2147 uint16_t internalPort, /* network byte order */ 2148 uint16_t externalPort, /* network byte order */ 2149 uint32_t ttl, /* time to live in seconds */ 2150 DNSServiceNATPortMappingReply callBack, 2151 void *context /* may be NULL */ 2152 ); 2153 2154 2155 /********************************************************************************************* 2156 * 2157 * General Utility Functions 2158 * 2159 *********************************************************************************************/ 2160 2161 /* DNSServiceConstructFullName() 2162 * 2163 * Concatenate a three-part domain name (as returned by the above callbacks) into a 2164 * properly-escaped full domain name. Note that callbacks in the above functions ALREADY ESCAPE 2165 * strings where necessary. 2166 * 2167 * Parameters: 2168 * 2169 * fullName: A pointer to a buffer that where the resulting full domain name is to be written. 2170 * The buffer must be kDNSServiceMaxDomainName (1009) bytes in length to 2171 * accommodate the longest legal domain name without buffer overrun. 2172 * 2173 * service: The service name - any dots or backslashes must NOT be escaped. 2174 * May be NULL (to construct a PTR record name, e.g. 2175 * "_ftp._tcp.apple.com."). 2176 * 2177 * regtype: The service type followed by the protocol, separated by a dot 2178 * (e.g. "_ftp._tcp"). 2179 * 2180 * domain: The domain name, e.g. "apple.com.". Literal dots or backslashes, 2181 * if any, must be escaped, e.g. "1st\. Floor.apple.com." 2182 * 2183 * return value: Returns kDNSServiceErr_NoError (0) on success, kDNSServiceErr_BadParam on error. 2184 * 2185 */ 2186 2187 DNSServiceErrorType DNSSD_API DNSServiceConstructFullName 2188 ( 2189 char * const fullName, 2190 const char * const service, /* may be NULL */ 2191 const char * const regtype, 2192 const char * const domain 2193 ); 2194 2195 2196 /********************************************************************************************* 2197 * 2198 * TXT Record Construction Functions 2199 * 2200 *********************************************************************************************/ 2201 2202 /* 2203 * A typical calling sequence for TXT record construction is something like: 2204 * 2205 * Client allocates storage for TXTRecord data (e.g. declare buffer on the stack) 2206 * TXTRecordCreate(); 2207 * TXTRecordSetValue(); 2208 * TXTRecordSetValue(); 2209 * TXTRecordSetValue(); 2210 * ... 2211 * DNSServiceRegister( ... TXTRecordGetLength(), TXTRecordGetBytesPtr() ... ); 2212 * TXTRecordDeallocate(); 2213 * Explicitly deallocate storage for TXTRecord data (if not allocated on the stack) 2214 */ 2215 2216 2217 /* TXTRecordRef 2218 * 2219 * Opaque internal data type. 2220 * Note: Represents a DNS-SD TXT record. 2221 */ 2222 2223 typedef union _TXTRecordRef_t { char PrivateData[16]; char *ForceNaturalAlignment; } TXTRecordRef; 2224 2225 2226 /* TXTRecordCreate() 2227 * 2228 * Creates a new empty TXTRecordRef referencing the specified storage. 2229 * 2230 * If the buffer parameter is NULL, or the specified storage size is not 2231 * large enough to hold a key subsequently added using TXTRecordSetValue(), 2232 * then additional memory will be added as needed using malloc(). 2233 * 2234 * On some platforms, when memory is low, malloc() may fail. In this 2235 * case, TXTRecordSetValue() will return kDNSServiceErr_NoMemory, and this 2236 * error condition will need to be handled as appropriate by the caller. 2237 * 2238 * You can avoid the need to handle this error condition if you ensure 2239 * that the storage you initially provide is large enough to hold all 2240 * the key/value pairs that are to be added to the record. 2241 * The caller can precompute the exact length required for all of the 2242 * key/value pairs to be added, or simply provide a fixed-sized buffer 2243 * known in advance to be large enough. 2244 * A no-value (key-only) key requires (1 + key length) bytes. 2245 * A key with empty value requires (1 + key length + 1) bytes. 2246 * A key with non-empty value requires (1 + key length + 1 + value length). 2247 * For most applications, DNS-SD TXT records are generally 2248 * less than 100 bytes, so in most cases a simple fixed-sized 2249 * 256-byte buffer will be more than sufficient. 2250 * Recommended size limits for DNS-SD TXT Records are discussed in 2251 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> 2252 * 2253 * Note: When passing parameters to and from these TXT record APIs, 2254 * the key name does not include the '=' character. The '=' character 2255 * is the separator between the key and value in the on-the-wire 2256 * packet format; it is not part of either the key or the value. 2257 * 2258 * txtRecord: A pointer to an uninitialized TXTRecordRef. 2259 * 2260 * bufferLen: The size of the storage provided in the "buffer" parameter. 2261 * 2262 * buffer: Optional caller-supplied storage used to hold the TXTRecord data. 2263 * This storage must remain valid for as long as 2264 * the TXTRecordRef. 2265 */ 2266 2267 void DNSSD_API TXTRecordCreate 2268 ( 2269 TXTRecordRef *txtRecord, 2270 uint16_t bufferLen, 2271 void *buffer 2272 ); 2273 2274 2275 /* TXTRecordDeallocate() 2276 * 2277 * Releases any resources allocated in the course of preparing a TXT Record 2278 * using TXTRecordCreate()/TXTRecordSetValue()/TXTRecordRemoveValue(). 2279 * Ownership of the buffer provided in TXTRecordCreate() returns to the client. 2280 * 2281 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 2282 * 2283 */ 2284 2285 void DNSSD_API TXTRecordDeallocate 2286 ( 2287 TXTRecordRef *txtRecord 2288 ); 2289 2290 2291 /* TXTRecordSetValue() 2292 * 2293 * Adds a key (optionally with value) to a TXTRecordRef. If the "key" already 2294 * exists in the TXTRecordRef, then the current value will be replaced with 2295 * the new value. 2296 * Keys may exist in four states with respect to a given TXT record: 2297 * - Absent (key does not appear at all) 2298 * - Present with no value ("key" appears alone) 2299 * - Present with empty value ("key=" appears in TXT record) 2300 * - Present with non-empty value ("key=value" appears in TXT record) 2301 * For more details refer to "Data Syntax for DNS-SD TXT Records" in 2302 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> 2303 * 2304 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 2305 * 2306 * key: A null-terminated string which only contains printable ASCII 2307 * values (0x20-0x7E), excluding '=' (0x3D). Keys should be 2308 * 9 characters or fewer (not counting the terminating null). 2309 * 2310 * valueSize: The size of the value. 2311 * 2312 * value: Any binary value. For values that represent 2313 * textual data, UTF-8 is STRONGLY recommended. 2314 * For values that represent textual data, valueSize 2315 * should NOT include the terminating null (if any) 2316 * at the end of the string. 2317 * If NULL, then "key" will be added with no value. 2318 * If non-NULL but valueSize is zero, then "key=" will be 2319 * added with empty value. 2320 * 2321 * return value: Returns kDNSServiceErr_NoError on success. 2322 * Returns kDNSServiceErr_Invalid if the "key" string contains 2323 * illegal characters. 2324 * Returns kDNSServiceErr_NoMemory if adding this key would 2325 * exceed the available storage. 2326 */ 2327 2328 DNSServiceErrorType DNSSD_API TXTRecordSetValue 2329 ( 2330 TXTRecordRef *txtRecord, 2331 const char *key, 2332 uint8_t valueSize, /* may be zero */ 2333 const void *value /* may be NULL */ 2334 ); 2335 2336 2337 /* TXTRecordRemoveValue() 2338 * 2339 * Removes a key from a TXTRecordRef. The "key" must be an 2340 * ASCII string which exists in the TXTRecordRef. 2341 * 2342 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 2343 * 2344 * key: A key name which exists in the TXTRecordRef. 2345 * 2346 * return value: Returns kDNSServiceErr_NoError on success. 2347 * Returns kDNSServiceErr_NoSuchKey if the "key" does not 2348 * exist in the TXTRecordRef. 2349 */ 2350 2351 DNSServiceErrorType DNSSD_API TXTRecordRemoveValue 2352 ( 2353 TXTRecordRef *txtRecord, 2354 const char *key 2355 ); 2356 2357 2358 /* TXTRecordGetLength() 2359 * 2360 * Allows you to determine the length of the raw bytes within a TXTRecordRef. 2361 * 2362 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 2363 * 2364 * return value: Returns the size of the raw bytes inside a TXTRecordRef 2365 * which you can pass directly to DNSServiceRegister() or 2366 * to DNSServiceUpdateRecord(). 2367 * Returns 0 if the TXTRecordRef is empty. 2368 */ 2369 2370 uint16_t DNSSD_API TXTRecordGetLength 2371 ( 2372 const TXTRecordRef *txtRecord 2373 ); 2374 2375 2376 /* TXTRecordGetBytesPtr() 2377 * 2378 * Allows you to retrieve a pointer to the raw bytes within a TXTRecordRef. 2379 * 2380 * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). 2381 * 2382 * return value: Returns a pointer to the raw bytes inside the TXTRecordRef 2383 * which you can pass directly to DNSServiceRegister() or 2384 * to DNSServiceUpdateRecord(). 2385 */ 2386 2387 const void * DNSSD_API TXTRecordGetBytesPtr 2388 ( 2389 const TXTRecordRef *txtRecord 2390 ); 2391 2392 2393 /********************************************************************************************* 2394 * 2395 * TXT Record Parsing Functions 2396 * 2397 *********************************************************************************************/ 2398 2399 /* 2400 * A typical calling sequence for TXT record parsing is something like: 2401 * 2402 * Receive TXT record data in DNSServiceResolve() callback 2403 * if (TXTRecordContainsKey(txtLen, txtRecord, "key")) then do something 2404 * val1ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key1", &len1); 2405 * val2ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key2", &len2); 2406 * ... 2407 * memcpy(myval1, val1ptr, len1); 2408 * memcpy(myval2, val2ptr, len2); 2409 * ... 2410 * return; 2411 * 2412 * If you wish to retain the values after return from the DNSServiceResolve() 2413 * callback, then you need to copy the data to your own storage using memcpy() 2414 * or similar, as shown in the example above. 2415 * 2416 * If for some reason you need to parse a TXT record you built yourself 2417 * using the TXT record construction functions above, then you can do 2418 * that using TXTRecordGetLength and TXTRecordGetBytesPtr calls: 2419 * TXTRecordGetValue(TXTRecordGetLength(x), TXTRecordGetBytesPtr(x), key, &len); 2420 * 2421 * Most applications only fetch keys they know about from a TXT record and 2422 * ignore the rest. 2423 * However, some debugging tools wish to fetch and display all keys. 2424 * To do that, use the TXTRecordGetCount() and TXTRecordGetItemAtIndex() calls. 2425 */ 2426 2427 /* TXTRecordContainsKey() 2428 * 2429 * Allows you to determine if a given TXT Record contains a specified key. 2430 * 2431 * txtLen: The size of the received TXT Record. 2432 * 2433 * txtRecord: Pointer to the received TXT Record bytes. 2434 * 2435 * key: A null-terminated ASCII string containing the key name. 2436 * 2437 * return value: Returns 1 if the TXT Record contains the specified key. 2438 * Otherwise, it returns 0. 2439 */ 2440 2441 int DNSSD_API TXTRecordContainsKey 2442 ( 2443 uint16_t txtLen, 2444 const void *txtRecord, 2445 const char *key 2446 ); 2447 2448 2449 /* TXTRecordGetValuePtr() 2450 * 2451 * Allows you to retrieve the value for a given key from a TXT Record. 2452 * 2453 * txtLen: The size of the received TXT Record 2454 * 2455 * txtRecord: Pointer to the received TXT Record bytes. 2456 * 2457 * key: A null-terminated ASCII string containing the key name. 2458 * 2459 * valueLen: On output, will be set to the size of the "value" data. 2460 * 2461 * return value: Returns NULL if the key does not exist in this TXT record, 2462 * or exists with no value (to differentiate between 2463 * these two cases use TXTRecordContainsKey()). 2464 * Returns pointer to location within TXT Record bytes 2465 * if the key exists with empty or non-empty value. 2466 * For empty value, valueLen will be zero. 2467 * For non-empty value, valueLen will be length of value data. 2468 */ 2469 2470 const void * DNSSD_API TXTRecordGetValuePtr 2471 ( 2472 uint16_t txtLen, 2473 const void *txtRecord, 2474 const char *key, 2475 uint8_t *valueLen 2476 ); 2477 2478 2479 /* TXTRecordGetCount() 2480 * 2481 * Returns the number of keys stored in the TXT Record. The count 2482 * can be used with TXTRecordGetItemAtIndex() to iterate through the keys. 2483 * 2484 * txtLen: The size of the received TXT Record. 2485 * 2486 * txtRecord: Pointer to the received TXT Record bytes. 2487 * 2488 * return value: Returns the total number of keys in the TXT Record. 2489 * 2490 */ 2491 2492 uint16_t DNSSD_API TXTRecordGetCount 2493 ( 2494 uint16_t txtLen, 2495 const void *txtRecord 2496 ); 2497 2498 2499 /* TXTRecordGetItemAtIndex() 2500 * 2501 * Allows you to retrieve a key name and value pointer, given an index into 2502 * a TXT Record. Legal index values range from zero to TXTRecordGetCount()-1. 2503 * It's also possible to iterate through keys in a TXT record by simply 2504 * calling TXTRecordGetItemAtIndex() repeatedly, beginning with index zero 2505 * and increasing until TXTRecordGetItemAtIndex() returns kDNSServiceErr_Invalid. 2506 * 2507 * On return: 2508 * For keys with no value, *value is set to NULL and *valueLen is zero. 2509 * For keys with empty value, *value is non-NULL and *valueLen is zero. 2510 * For keys with non-empty value, *value is non-NULL and *valueLen is non-zero. 2511 * 2512 * txtLen: The size of the received TXT Record. 2513 * 2514 * txtRecord: Pointer to the received TXT Record bytes. 2515 * 2516 * itemIndex: An index into the TXT Record. 2517 * 2518 * keyBufLen: The size of the string buffer being supplied. 2519 * 2520 * key: A string buffer used to store the key name. 2521 * On return, the buffer contains a null-terminated C string 2522 * giving the key name. DNS-SD TXT keys are usually 2523 * 9 characters or fewer. To hold the maximum possible 2524 * key name, the buffer should be 256 bytes long. 2525 * 2526 * valueLen: On output, will be set to the size of the "value" data. 2527 * 2528 * value: On output, *value is set to point to location within TXT 2529 * Record bytes that holds the value data. 2530 * 2531 * return value: Returns kDNSServiceErr_NoError on success. 2532 * Returns kDNSServiceErr_NoMemory if keyBufLen is too short. 2533 * Returns kDNSServiceErr_Invalid if index is greater than 2534 * TXTRecordGetCount()-1. 2535 */ 2536 2537 DNSServiceErrorType DNSSD_API TXTRecordGetItemAtIndex 2538 ( 2539 uint16_t txtLen, 2540 const void *txtRecord, 2541 uint16_t itemIndex, 2542 uint16_t keyBufLen, 2543 char *key, 2544 uint8_t *valueLen, 2545 const void **value 2546 ); 2547 2548 #if _DNS_SD_LIBDISPATCH 2549 /* 2550 * DNSServiceSetDispatchQueue 2551 * 2552 * Allows you to schedule a DNSServiceRef on a serial dispatch queue for receiving asynchronous 2553 * callbacks. It's the clients responsibility to ensure that the provided dispatch queue is running. 2554 * 2555 * A typical application that uses CFRunLoopRun or dispatch_main on its main thread will 2556 * usually schedule DNSServiceRefs on its main queue (which is always a serial queue) 2557 * using "DNSServiceSetDispatchQueue(sdref, dispatch_get_main_queue());" 2558 * 2559 * If there is any error during the processing of events, the application callback will 2560 * be called with an error code. For shared connections, each subordinate DNSServiceRef 2561 * will get its own error callback. Currently these error callbacks only happen 2562 * if the daemon is manually terminated or crashes, and the error 2563 * code in this case is kDNSServiceErr_ServiceNotRunning. The application must call 2564 * DNSServiceRefDeallocate to free the DNSServiceRef when it gets such an error code. 2565 * These error callbacks are rare and should not normally happen on customer machines, 2566 * but application code should be written defensively to handle such error callbacks 2567 * gracefully if they occur. 2568 * 2569 * After using DNSServiceSetDispatchQueue on a DNSServiceRef, calling DNSServiceProcessResult 2570 * on the same DNSServiceRef will result in undefined behavior and should be avoided. 2571 * 2572 * Once the application successfully schedules a DNSServiceRef on a serial dispatch queue using 2573 * DNSServiceSetDispatchQueue, it cannot remove the DNSServiceRef from the dispatch queue, or use 2574 * DNSServiceSetDispatchQueue a second time to schedule the DNSServiceRef onto a different serial dispatch 2575 * queue. Once scheduled onto a dispatch queue a DNSServiceRef will deliver events to that queue until 2576 * the application no longer requires that operation and terminates it using DNSServiceRefDeallocate. 2577 * 2578 * service: DNSServiceRef that was allocated and returned to the application, when the 2579 * application calls one of the DNSService API. 2580 * 2581 * queue: dispatch queue where the application callback will be scheduled 2582 * 2583 * return value: Returns kDNSServiceErr_NoError on success. 2584 * Returns kDNSServiceErr_NoMemory if it cannot create a dispatch source 2585 * Returns kDNSServiceErr_BadParam if the service param is invalid or the 2586 * queue param is invalid 2587 */ 2588 2589 DNSServiceErrorType DNSSD_API DNSServiceSetDispatchQueue 2590 ( 2591 DNSServiceRef service, 2592 dispatch_queue_t queue 2593 ); 2594 #endif //_DNS_SD_LIBDISPATCH 2595 2596 #if !defined(_WIN32) 2597 typedef void (DNSSD_API *DNSServiceSleepKeepaliveReply) 2598 ( 2599 DNSServiceRef sdRef, 2600 DNSServiceErrorType errorCode, 2601 void *context 2602 ); 2603 DNSServiceErrorType DNSSD_API DNSServiceSleepKeepalive 2604 ( 2605 DNSServiceRef *sdRef, 2606 DNSServiceFlags flags, 2607 int fd, 2608 unsigned int timeout, 2609 DNSServiceSleepKeepaliveReply callBack, 2610 void *context 2611 ); 2612 #endif 2613 2614 #ifdef __APPLE_API_PRIVATE 2615 2616 #define kDNSServiceCompPrivateDNS "PrivateDNS" 2617 #define kDNSServiceCompMulticastDNS "MulticastDNS" 2618 2619 #endif //__APPLE_API_PRIVATE 2620 2621 /* Some C compiler cleverness. We can make the compiler check certain things for us, 2622 * and report errors at compile-time if anything is wrong. The usual way to do this would 2623 * be to use a run-time "if" statement or the conventional run-time "assert" mechanism, but 2624 * then you don't find out what's wrong until you run the software. This way, if the assertion 2625 * condition is false, the array size is negative, and the complier complains immediately. 2626 */ 2627 2628 struct CompileTimeAssertionChecks_DNS_SD 2629 { 2630 char assert0[(sizeof(union _TXTRecordRef_t) == 16) ? 1 : -1]; 2631 }; 2632 2633 #ifdef __cplusplus 2634 } 2635 #endif 2636 2637 #endif /* _DNS_SD_H */ 2638