1/* -*- Mode: C; tab-width: 4 -*-
2 *
3 * Copyright (c) 2003-2004, Apple Computer, Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright notice,
9 *     this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright notice,
11 *     this list of conditions and the following disclaimer in the documentation
12 *     and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of its
14 *     contributors may be used to endorse or promote products derived from this
15 *     software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
26 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29
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
58/* _DNS_SD_H contains the mDNSResponder version number for this header file, formatted as follows:
59 *   Major part of the build number * 10000 +
60 *   minor part of the build number *   100
61 * For example, Mac OS X 10.4.9 has mDNSResponder-108.4, which would be represented as
62 * version 1080400. This allows C code to do simple greater-than and less-than comparisons:
63 * e.g. an application that requires the DNSServiceGetProperty() call (new in mDNSResponder-126) can check:
64 *
65 *   #if _DNS_SD_H+0 >= 1260000
66 *   ... some C code that calls DNSServiceGetProperty() ...
67 *   #endif
68 *
69 * The version defined in this header file symbol allows for compile-time
70 * checking, so that C code building with earlier versions of the header file
71 * can avoid compile errors trying to use functions that aren't even defined
72 * in those earlier versions. Similar checks may also be performed at run-time:
73 *  => weak linking -- to avoid link failures if run with an earlier
74 *     version of the library that's missing some desired symbol, or
75 *  => DNSServiceGetProperty(DaemonVersion) -- to verify whether the running daemon
76 *     ("system service" on Windows) meets some required minimum functionality level.
77 */
78
79#ifndef _DNS_SD_H
80#define _DNS_SD_H 3201080
81
82#ifdef  __cplusplus
83    extern "C" {
84#endif
85
86/* Set to 1 if libdispatch is supported
87 * Note: May also be set by project and/or Makefile
88 */
89#ifndef _DNS_SD_LIBDISPATCH
90#define _DNS_SD_LIBDISPATCH 0
91#endif /* ndef _DNS_SD_LIBDISPATCH */
92
93/* standard calling convention under Win32 is __stdcall */
94/* Note: When compiling Intel EFI (Extensible Firmware Interface) under MS Visual Studio, the */
95/* _WIN32 symbol is defined by the compiler even though it's NOT compiling code for Windows32 */
96#if defined(_WIN32) && !defined(EFI32) && !defined(EFI64)
97#define DNSSD_API __stdcall
98#else
99#define DNSSD_API
100#endif
101
102/* stdint.h does not exist on FreeBSD 4.x; its types are defined in sys/types.h instead */
103#if defined(__FreeBSD__) && (__FreeBSD__ < 5)
104#include <sys/types.h>
105
106/* Likewise, on Sun, standard integer types are in sys/types.h */
107#elif defined(__sun__)
108#include <sys/types.h>
109
110/* EFI does not have stdint.h, or anything else equivalent */
111#elif defined(EFI32) || defined(EFI64) || defined(EFIX64)
112#include "Tiano.h"
113#if !defined(_STDINT_H_)
114typedef UINT8       uint8_t;
115typedef INT8        int8_t;
116typedef UINT16      uint16_t;
117typedef INT16       int16_t;
118typedef UINT32      uint32_t;
119typedef INT32       int32_t;
120#endif
121/* Windows has its own differences */
122#elif defined(_WIN32)
123#include <windows.h>
124#define _UNUSED
125#ifndef _MSL_STDINT_H
126typedef UINT8       uint8_t;
127typedef INT8        int8_t;
128typedef UINT16      uint16_t;
129typedef INT16       int16_t;
130typedef UINT32      uint32_t;
131typedef INT32       int32_t;
132#endif
133
134/* All other Posix platforms use stdint.h */
135#else
136#include <stdint.h>
137#endif
138
139#if _DNS_SD_LIBDISPATCH
140#include <dispatch/dispatch.h>
141#endif
142
143/* DNSServiceRef, DNSRecordRef
144 *
145 * Opaque internal data types.
146 * Note: client is responsible for serializing access to these structures if
147 * they are shared between concurrent threads.
148 */
149
150typedef struct _DNSServiceRef_t *DNSServiceRef;
151typedef struct _DNSRecordRef_t *DNSRecordRef;
152
153struct sockaddr;
154
155/*! @enum General flags
156 * Most DNS-SD API functions and callbacks include a DNSServiceFlags parameter.
157 * As a general rule, any given bit in the 32-bit flags field has a specific fixed meaning,
158 * regardless of the function or callback being used. For any given function or callback,
159 * typically only a subset of the possible flags are meaningful, and all others should be zero.
160 * The discussion section for each API call describes which flags are valid for that call
161 * and callback. In some cases, for a particular call, it may be that no flags are currently
162 * defined, in which case the DNSServiceFlags parameter exists purely to allow future expansion.
163 * In all cases, developers should expect that in future releases, it is possible that new flag
164 * values will be defined, and write code with this in mind. For example, code that tests
165 *     if (flags == kDNSServiceFlagsAdd) ...
166 * will fail if, in a future release, another bit in the 32-bit flags field is also set.
167 * The reliable way to test whether a particular bit is set is not with an equality test,
168 * but with a bitwise mask:
169 *     if (flags & kDNSServiceFlagsAdd) ...
170 */
171enum
172    {
173    kDNSServiceFlagsMoreComing          = 0x1,
174    /* MoreComing indicates to a callback that at least one more result is
175     * queued and will be delivered following immediately after this one.
176     * When the MoreComing flag is set, applications should not immediately
177     * update their UI, because this can result in a great deal of ugly flickering
178     * on the screen, and can waste a great deal of CPU time repeatedly updating
179     * the screen with content that is then immediately erased, over and over.
180     * Applications should wait until until MoreComing is not set, and then
181     * update their UI when no more changes are imminent.
182     * When MoreComing is not set, that doesn't mean there will be no more
183     * answers EVER, just that there are no more answers immediately
184     * available right now at this instant. If more answers become available
185     * in the future they will be delivered as usual.
186     */
187
188    kDNSServiceFlagsAdd                 = 0x2,
189    kDNSServiceFlagsDefault             = 0x4,
190    /* Flags for domain enumeration and browse/query reply callbacks.
191     * "Default" applies only to enumeration and is only valid in
192     * conjunction with "Add". An enumeration callback with the "Add"
193     * flag NOT set indicates a "Remove", i.e. the domain is no longer
194     * valid.
195     */
196
197    kDNSServiceFlagsNoAutoRename        = 0x8,
198    /* Flag for specifying renaming behavior on name conflict when registering
199     * non-shared records. By default, name conflicts are automatically handled
200     * by renaming the service. NoAutoRename overrides this behavior - with this
201     * flag set, name conflicts will result in a callback. The NoAutorename flag
202     * is only valid if a name is explicitly specified when registering a service
203     * (i.e. the default name is not used.)
204     */
205
206    kDNSServiceFlagsShared              = 0x10,
207    kDNSServiceFlagsUnique              = 0x20,
208    /* Flag for registering individual records on a connected
209     * DNSServiceRef. Shared indicates that there may be multiple records
210     * with this name on the network (e.g. PTR records). Unique indicates that the
211     * record's name is to be unique on the network (e.g. SRV records).
212     */
213
214    kDNSServiceFlagsBrowseDomains       = 0x40,
215    kDNSServiceFlagsRegistrationDomains = 0x80,
216    /* Flags for specifying domain enumeration type in DNSServiceEnumerateDomains.
217     * BrowseDomains enumerates domains recommended for browsing, RegistrationDomains
218     * enumerates domains recommended for registration.
219     */
220
221    kDNSServiceFlagsLongLivedQuery      = 0x100,
222    /* Flag for creating a long-lived unicast query for the DNSServiceQueryRecord call. */
223
224    kDNSServiceFlagsAllowRemoteQuery    = 0x200,
225    /* Flag for creating a record for which we will answer remote queries
226     * (queries from hosts more than one hop away; hosts not directly connected to the local link).
227     */
228
229    kDNSServiceFlagsForceMulticast      = 0x400,
230    /* Flag for signifying that a query or registration should be performed exclusively via multicast
231     * DNS, even for a name in a domain (e.g. foo.apple.com.) that would normally imply unicast DNS.
232     */
233
234    kDNSServiceFlagsForce               = 0x800,
235    /* Flag for signifying a "stronger" variant of an operation.
236     * Currently defined only for DNSServiceReconfirmRecord(), where it forces a record to
237     * be removed from the cache immediately, instead of querying for a few seconds before
238     * concluding that the record is no longer valid and then removing it. This flag should
239     * be used with caution because if a service browsing PTR record is indeed still valid
240     * on the network, forcing its removal will result in a user-interface flap -- the
241     * discovered service instance will disappear, and then re-appear moments later.
242     */
243
244    kDNSServiceFlagsReturnIntermediates = 0x1000,
245    /* Flag for returning intermediate results.
246     * For example, if a query results in an authoritative NXDomain (name does not exist)
247     * then that result is returned to the client. However the query is not implicitly
248     * cancelled -- it remains active and if the answer subsequently changes
249     * (e.g. because a VPN tunnel is subsequently established) then that positive
250     * result will still be returned to the client.
251     * Similarly, if a query results in a CNAME record, then in addition to following
252     * the CNAME referral, the intermediate CNAME result is also returned to the client.
253     * When this flag is not set, NXDomain errors are not returned, and CNAME records
254     * are followed silently without informing the client of the intermediate steps.
255     * (In earlier builds this flag was briefly calledkDNSServiceFlagsReturnCNAME)
256     */
257
258    kDNSServiceFlagsNonBrowsable        = 0x2000,
259    /* A service registered with the NonBrowsable flag set can be resolved using
260     * DNSServiceResolve(), but will not be discoverable using DNSServiceBrowse().
261     * This is for cases where the name is actually a GUID; it is found by other means;
262     * there is no end-user benefit to browsing to find a long list of opaque GUIDs.
263     * Using the NonBrowsable flag creates SRV+TXT without the cost of also advertising
264     * an associated PTR record.
265     */
266
267    kDNSServiceFlagsShareConnection     = 0x4000,
268    /* For efficiency, clients that perform many concurrent operations may want to use a
269     * single Unix Domain Socket connection with the background daemon, instead of having a
270     * separate connection for each independent operation. To use this mode, clients first
271     * call DNSServiceCreateConnection(&MainRef) to initialize the main DNSServiceRef.
272     * For each subsequent operation that is to share that same connection, the client copies
273     * the MainRef, and then passes the address of that copy, setting the ShareConnection flag
274     * to tell the library that this DNSServiceRef is not a typical uninitialized DNSServiceRef;
275     * it's a copy of an existing DNSServiceRef whose connection information should be reused.
276     *
277     * For example:
278     *
279     * DNSServiceErrorType error;
280     * DNSServiceRef MainRef;
281     * error = DNSServiceCreateConnection(&MainRef);
282     * if (error) ...
283     * DNSServiceRef BrowseRef = MainRef;  // Important: COPY the primary DNSServiceRef first...
284     * error = DNSServiceBrowse(&BrowseRef, kDNSServiceFlagsShareConnection, ...); // then use the copy
285     * if (error) ...
286     * ...
287     * DNSServiceRefDeallocate(BrowseRef); // Terminate the browse operation
288     * DNSServiceRefDeallocate(MainRef);   // Terminate the shared connection
289     *
290     * Notes:
291     *
292     * 1. Collective kDNSServiceFlagsMoreComing flag
293     * When callbacks are invoked using a shared DNSServiceRef, the
294     * kDNSServiceFlagsMoreComing flag applies collectively to *all* active
295     * operations sharing the same parent DNSServiceRef. If the MoreComing flag is
296     * set it means that there are more results queued on this parent DNSServiceRef,
297     * but not necessarily more results for this particular callback function.
298     * The implication of this for client programmers is that when a callback
299     * is invoked with the MoreComing flag set, the code should update its
300     * internal data structures with the new result, and set a variable indicating
301     * that its UI needs to be updated. Then, later when a callback is eventually
302     * invoked with the MoreComing flag not set, the code should update *all*
303     * stale UI elements related to that shared parent DNSServiceRef that need
304     * updating, not just the UI elements related to the particular callback
305     * that happened to be the last one to be invoked.
306     *
307     * 2. Canceling operations and kDNSServiceFlagsMoreComing
308     * Whenever you cancel any operation for which you had deferred UI updates
309     * waiting because of a kDNSServiceFlagsMoreComing flag, you should perform
310     * those deferred UI updates. This is because, after cancelling the operation,
311     * you can no longer wait for a callback *without* MoreComing set, to tell
312     * you do perform your deferred UI updates (the operation has been canceled,
313     * so there will be no more callbacks). An implication of the collective
314     * kDNSServiceFlagsMoreComing flag for shared connections is that this
315     * guideline applies more broadly -- any time you cancel an operation on
316     * a shared connection, you should perform all deferred UI updates for all
317     * operations sharing that connection. This is because the MoreComing flag
318     * might have been referring to events coming for the operation you canceled,
319     * which will now not be coming because the operation has been canceled.
320     *
321     * 3. Only share DNSServiceRef's created with DNSServiceCreateConnection
322     * Calling DNSServiceCreateConnection(&ref) creates a special shareable DNSServiceRef.
323     * DNSServiceRef's created by other calls like DNSServiceBrowse() or DNSServiceResolve()
324     * cannot be shared by copying them and using kDNSServiceFlagsShareConnection.
325     *
326     * 4. Don't Double-Deallocate
327     * Calling DNSServiceRefDeallocate(ref) for a particular operation's DNSServiceRef terminates
328     * just that operation. Calling DNSServiceRefDeallocate(ref) for the main shared DNSServiceRef
329     * (the parent DNSServiceRef, originally created by DNSServiceCreateConnection(&ref))
330     * automatically terminates the shared connection and all operations that were still using it.
331     * After doing this, DO NOT then attempt to deallocate any remaining subordinate DNSServiceRef's.
332     * The memory used by those subordinate DNSServiceRef's has already been freed, so any attempt
333     * to do a DNSServiceRefDeallocate (or any other operation) on them will result in accesses
334     * to freed memory, leading to crashes or other equally undesirable results.
335     *
336     * 5. Thread Safety
337     * The dns_sd.h API does not presuppose any particular threading model, and consequently
338     * does no locking of its own (which would require linking some specific threading library).
339     * If client code calls API routines on the same DNSServiceRef concurrently
340     * from multiple threads, it is the client's responsibility to use a mutext
341     * lock or take similar appropriate precautions to serialize those calls.
342     */
343
344    kDNSServiceFlagsSuppressUnusable    = 0x8000,
345	/*
346	 * This flag is meaningful only in DNSServiceQueryRecord which suppresses unusable queries on the
347	 * wire. If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name)
348	 * but this host has no routable IPv6 address, then the call will not try to look up IPv6 addresses
349	 * for "hostname", since any addresses it found would be unlikely to be of any use anyway. Similarly,
350	 * if this host has no routable IPv4 address, the call will not try to look up IPv4 addresses for
351	 * "hostname".
352	 */
353
354    kDNSServiceFlagsTimeout            = 0x10000,
355	/*
356	 * When kDNServiceFlagsTimeout is passed to DNSServiceQueryRecord or DNSServiceGetAddrInfo, the query is
357	 * stopped after a certain number of seconds have elapsed. The time at which the query will be stopped
358	 * is determined by the system and cannot be configured by the user. The query will be stopped irrespective
359	 * of whether a response was given earlier or not. When the query is stopped, the callback will be called
360	 * with an error code of kDNSServiceErr_Timeout and a NULL sockaddr will be returned for DNSServiceGetAddrInfo
361	 * and zero length rdata will be returned for DNSServiceQueryRecord.
362	 */
363
364    kDNSServiceFlagsIncludeP2P          = 0x20000,
365	/*
366	 * Include P2P interfaces when kDNSServiceInterfaceIndexAny is specified.
367	 * By default, specifying kDNSServiceInterfaceIndexAny does not include P2P interfaces.
368	 */
369	kDNSServiceFlagsWakeOnResolve      = 0x40000
370	/*
371	 * This flag is meaningful only in DNSServiceResolve. When set, it tries to send a magic packet
372	 * to wake up the client.
373	 */
374    };
375
376/* Possible protocols for DNSServiceNATPortMappingCreate(). */
377enum
378    {
379    kDNSServiceProtocol_IPv4 = 0x01,
380    kDNSServiceProtocol_IPv6 = 0x02,
381    /* 0x04 and 0x08 reserved for future internetwork protocols */
382
383    kDNSServiceProtocol_UDP  = 0x10,
384    kDNSServiceProtocol_TCP  = 0x20
385    /* 0x40 and 0x80 reserved for future transport protocols, e.g. SCTP [RFC 2960]
386     * or DCCP [RFC 4340]. If future NAT gateways are created that support port
387     * mappings for these protocols, new constants will be defined here.
388     */
389    };
390
391/*
392 * The values for DNS Classes and Types are listed in RFC 1035, and are available
393 * on every OS in its DNS header file. Unfortunately every OS does not have the
394 * same header file containing DNS Class and Type constants, and the names of
395 * the constants are not consistent. For example, BIND 8 uses "T_A",
396 * BIND 9 uses "ns_t_a", Windows uses "DNS_TYPE_A", etc.
397 * For this reason, these constants are also listed here, so that code using
398 * the DNS-SD programming APIs can use these constants, so that the same code
399 * can compile on all our supported platforms.
400 */
401
402enum
403    {
404    kDNSServiceClass_IN       = 1       /* Internet */
405    };
406
407enum
408    {
409    kDNSServiceType_A          = 1,      /* Host address. */
410    kDNSServiceType_NS         = 2,      /* Authoritative server. */
411    kDNSServiceType_MD         = 3,      /* Mail destination. */
412    kDNSServiceType_MF         = 4,      /* Mail forwarder. */
413    kDNSServiceType_CNAME      = 5,      /* Canonical name. */
414    kDNSServiceType_SOA        = 6,      /* Start of authority zone. */
415    kDNSServiceType_MB         = 7,      /* Mailbox domain name. */
416    kDNSServiceType_MG         = 8,      /* Mail group member. */
417    kDNSServiceType_MR         = 9,      /* Mail rename name. */
418    kDNSServiceType_NULL       = 10,     /* Null resource record. */
419    kDNSServiceType_WKS        = 11,     /* Well known service. */
420    kDNSServiceType_PTR        = 12,     /* Domain name pointer. */
421    kDNSServiceType_HINFO      = 13,     /* Host information. */
422    kDNSServiceType_MINFO      = 14,     /* Mailbox information. */
423    kDNSServiceType_MX         = 15,     /* Mail routing information. */
424    kDNSServiceType_TXT        = 16,     /* One or more text strings (NOT "zero or more..."). */
425    kDNSServiceType_RP         = 17,     /* Responsible person. */
426    kDNSServiceType_AFSDB      = 18,     /* AFS cell database. */
427    kDNSServiceType_X25        = 19,     /* X_25 calling address. */
428    kDNSServiceType_ISDN       = 20,     /* ISDN calling address. */
429    kDNSServiceType_RT         = 21,     /* Router. */
430    kDNSServiceType_NSAP       = 22,     /* NSAP address. */
431    kDNSServiceType_NSAP_PTR   = 23,     /* Reverse NSAP lookup (deprecated). */
432    kDNSServiceType_SIG        = 24,     /* Security signature. */
433    kDNSServiceType_KEY        = 25,     /* Security key. */
434    kDNSServiceType_PX         = 26,     /* X.400 mail mapping. */
435    kDNSServiceType_GPOS       = 27,     /* Geographical position (withdrawn). */
436    kDNSServiceType_AAAA       = 28,     /* IPv6 Address. */
437    kDNSServiceType_LOC        = 29,     /* Location Information. */
438    kDNSServiceType_NXT        = 30,     /* Next domain (security). */
439    kDNSServiceType_EID        = 31,     /* Endpoint identifier. */
440    kDNSServiceType_NIMLOC     = 32,     /* Nimrod Locator. */
441    kDNSServiceType_SRV        = 33,     /* Server Selection. */
442    kDNSServiceType_ATMA       = 34,     /* ATM Address */
443    kDNSServiceType_NAPTR      = 35,     /* Naming Authority PoinTeR */
444    kDNSServiceType_KX         = 36,     /* Key Exchange */
445    kDNSServiceType_CERT       = 37,     /* Certification record */
446    kDNSServiceType_A6         = 38,     /* IPv6 Address (deprecated) */
447    kDNSServiceType_DNAME      = 39,     /* Non-terminal DNAME (for IPv6) */
448    kDNSServiceType_SINK       = 40,     /* Kitchen sink (experimental) */
449    kDNSServiceType_OPT        = 41,     /* EDNS0 option (meta-RR) */
450    kDNSServiceType_APL        = 42,     /* Address Prefix List */
451    kDNSServiceType_DS         = 43,     /* Delegation Signer */
452    kDNSServiceType_SSHFP      = 44,     /* SSH Key Fingerprint */
453    kDNSServiceType_IPSECKEY   = 45,     /* IPSECKEY */
454    kDNSServiceType_RRSIG      = 46,     /* RRSIG */
455    kDNSServiceType_NSEC       = 47,     /* Denial of Existence */
456    kDNSServiceType_DNSKEY     = 48,     /* DNSKEY */
457    kDNSServiceType_DHCID      = 49,     /* DHCP Client Identifier */
458    kDNSServiceType_NSEC3      = 50,     /* Hashed Authenticated Denial of Existence */
459    kDNSServiceType_NSEC3PARAM = 51,     /* Hashed Authenticated Denial of Existence */
460
461    kDNSServiceType_HIP        = 55,     /* Host Identity Protocol */
462
463    kDNSServiceType_SPF        = 99,     /* Sender Policy Framework for E-Mail */
464    kDNSServiceType_UINFO      = 100,    /* IANA-Reserved */
465    kDNSServiceType_UID        = 101,    /* IANA-Reserved */
466    kDNSServiceType_GID        = 102,    /* IANA-Reserved */
467    kDNSServiceType_UNSPEC     = 103,    /* IANA-Reserved */
468
469    kDNSServiceType_TKEY       = 249,    /* Transaction key */
470    kDNSServiceType_TSIG       = 250,    /* Transaction signature. */
471    kDNSServiceType_IXFR       = 251,    /* Incremental zone transfer. */
472    kDNSServiceType_AXFR       = 252,    /* Transfer zone of authority. */
473    kDNSServiceType_MAILB      = 253,    /* Transfer mailbox records. */
474    kDNSServiceType_MAILA      = 254,    /* Transfer mail agent records. */
475    kDNSServiceType_ANY        = 255     /* Wildcard match. */
476    };
477
478/* possible error code values */
479enum
480    {
481    kDNSServiceErr_NoError                   = 0,
482    kDNSServiceErr_Unknown                   = -65537,  /* 0xFFFE FFFF */
483    kDNSServiceErr_NoSuchName                = -65538,
484    kDNSServiceErr_NoMemory                  = -65539,
485    kDNSServiceErr_BadParam                  = -65540,
486    kDNSServiceErr_BadReference              = -65541,
487    kDNSServiceErr_BadState                  = -65542,
488    kDNSServiceErr_BadFlags                  = -65543,
489    kDNSServiceErr_Unsupported               = -65544,
490    kDNSServiceErr_NotInitialized            = -65545,
491    kDNSServiceErr_AlreadyRegistered         = -65547,
492    kDNSServiceErr_NameConflict              = -65548,
493    kDNSServiceErr_Invalid                   = -65549,
494    kDNSServiceErr_Firewall                  = -65550,
495    kDNSServiceErr_Incompatible              = -65551,  /* client library incompatible with daemon */
496    kDNSServiceErr_BadInterfaceIndex         = -65552,
497    kDNSServiceErr_Refused                   = -65553,
498    kDNSServiceErr_NoSuchRecord              = -65554,
499    kDNSServiceErr_NoAuth                    = -65555,
500    kDNSServiceErr_NoSuchKey                 = -65556,
501    kDNSServiceErr_NATTraversal              = -65557,
502    kDNSServiceErr_DoubleNAT                 = -65558,
503    kDNSServiceErr_BadTime                   = -65559,  /* Codes up to here existed in Tiger */
504    kDNSServiceErr_BadSig                    = -65560,
505    kDNSServiceErr_BadKey                    = -65561,
506    kDNSServiceErr_Transient                 = -65562,
507    kDNSServiceErr_ServiceNotRunning         = -65563,  /* Background daemon not running */
508    kDNSServiceErr_NATPortMappingUnsupported = -65564,  /* NAT doesn't support NAT-PMP or UPnP */
509    kDNSServiceErr_NATPortMappingDisabled    = -65565,  /* NAT supports NAT-PMP or UPnP but it's disabled by the administrator */
510    kDNSServiceErr_NoRouter                  = -65566,  /* No router currently configured (probably no network connectivity) */
511    kDNSServiceErr_PollingMode               = -65567,
512    kDNSServiceErr_Timeout                   = -65568
513
514    /* mDNS Error codes are in the range
515     * FFFE FF00 (-65792) to FFFE FFFF (-65537) */
516    };
517
518/* Maximum length, in bytes, of a service name represented as a */
519/* literal C-String, including the terminating NULL at the end. */
520
521#define kDNSServiceMaxServiceName 64
522
523/* Maximum length, in bytes, of a domain name represented as an *escaped* C-String */
524/* including the final trailing dot, and the C-String terminating NULL at the end. */
525
526#define kDNSServiceMaxDomainName 1009
527
528/*
529 * Notes on DNS Name Escaping
530 *   -- or --
531 * "Why is kDNSServiceMaxDomainName 1009, when the maximum legal domain name is 256 bytes?"
532 *
533 * All strings used in the DNS-SD APIs are UTF-8 strings. Apart from the exceptions noted below,
534 * the APIs expect the strings to be properly escaped, using the conventional DNS escaping rules:
535 *
536 *   '\\' represents a single literal '\' in the name
537 *   '\.' represents a single literal '.' in the name
538 *   '\ddd', where ddd is a three-digit decimal value from 000 to 255,
539 *        represents a single literal byte with that value.
540 *   A bare unescaped '.' is a label separator, marking a boundary between domain and subdomain.
541 *
542 * The exceptions, that do not use escaping, are the routines where the full
543 * DNS name of a resource is broken, for convenience, into servicename/regtype/domain.
544 * In these routines, the "servicename" is NOT escaped. It does not need to be, since
545 * it is, by definition, just a single literal string. Any characters in that string
546 * represent exactly what they are. The "regtype" portion is, technically speaking,
547 * escaped, but since legal regtypes are only allowed to contain letters, digits,
548 * and hyphens, there is nothing to escape, so the issue is moot. The "domain"
549 * portion is also escaped, though most domains in use on the public Internet
550 * today, like regtypes, don't contain any characters that need to be escaped.
551 * As DNS-SD becomes more popular, rich-text domains for service discovery will
552 * become common, so software should be written to cope with domains with escaping.
553 *
554 * The servicename may be up to 63 bytes of UTF-8 text (not counting the C-String
555 * terminating NULL at the end). The regtype is of the form _service._tcp or
556 * _service._udp, where the "service" part is 1-15 characters, which may be
557 * letters, digits, or hyphens. The domain part of the three-part name may be
558 * any legal domain, providing that the resulting servicename+regtype+domain
559 * name does not exceed 256 bytes.
560 *
561 * For most software, these issues are transparent. When browsing, the discovered
562 * servicenames should simply be displayed as-is. When resolving, the discovered
563 * servicename/regtype/domain are simply passed unchanged to DNSServiceResolve().
564 * When a DNSServiceResolve() succeeds, the returned fullname is already in
565 * the correct format to pass to standard system DNS APIs such as res_query().
566 * For converting from servicename/regtype/domain to a single properly-escaped
567 * full DNS name, the helper function DNSServiceConstructFullName() is provided.
568 *
569 * The following (highly contrived) example illustrates the escaping process.
570 * Suppose you have an service called "Dr. Smith\Dr. Johnson", of type "_ftp._tcp"
571 * in subdomain "4th. Floor" of subdomain "Building 2" of domain "apple.com."
572 * The full (escaped) DNS name of this service's SRV record would be:
573 * Dr\.\032Smith\\Dr\.\032Johnson._ftp._tcp.4th\.\032Floor.Building\0322.apple.com.
574 */
575
576
577/*
578 * Constants for specifying an interface index
579 *
580 * Specific interface indexes are identified via a 32-bit unsigned integer returned
581 * by the if_nametoindex() family of calls.
582 *
583 * If the client passes 0 for interface index, that means "do the right thing",
584 * which (at present) means, "if the name is in an mDNS local multicast domain
585 * (e.g. 'local.', '254.169.in-addr.arpa.', '{8,9,A,B}.E.F.ip6.arpa.') then multicast
586 * on all applicable interfaces, otherwise send via unicast to the appropriate
587 * DNS server." Normally, most clients will use 0 for interface index to
588 * automatically get the default sensible behaviour.
589 *
590 * If the client passes a positive interface index, then for multicast names that
591 * indicates to do the operation only on that one interface. For unicast names the
592 * interface index is ignored unless kDNSServiceFlagsForceMulticast is also set.
593 *
594 * If the client passes kDNSServiceInterfaceIndexLocalOnly when registering
595 * a service, then that service will be found *only* by other local clients
596 * on the same machine that are browsing using kDNSServiceInterfaceIndexLocalOnly
597 * or kDNSServiceInterfaceIndexAny.
598 * If a client has a 'private' service, accessible only to other processes
599 * running on the same machine, this allows the client to advertise that service
600 * in a way such that it does not inadvertently appear in service lists on
601 * all the other machines on the network.
602 *
603 * If the client passes kDNSServiceInterfaceIndexLocalOnly when browsing
604 * then it will find *all* records registered on that same local machine.
605 * Clients explicitly wishing to discover *only* LocalOnly services can
606 * accomplish this by inspecting the interfaceIndex of each service reported
607 * to their DNSServiceBrowseReply() callback function, and discarding those
608 * where the interface index is not kDNSServiceInterfaceIndexLocalOnly.
609 *
610 * kDNSServiceInterfaceIndexP2P is meaningful only in Browse, QueryRecord,
611 * and Resolve operations. It should not be used in other DNSService APIs.
612 *
613 * - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceBrowse or
614 *   DNSServiceQueryRecord, it restricts the operation to P2P.
615 *
616 * - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceResolve, it is
617 *   mapped internally to kDNSServiceInterfaceIndexAny, because resolving
618 *   a P2P service may create and/or enable an interface whose index is not
619 *   known a priori. The resolve callback will indicate the index of the
620 *   interface via which the service can be accessed.
621 *
622 * If applications pass kDNSServiceInterfaceIndexAny to DNSServiceBrowse
623 * or DNSServiceQueryRecord, they must set the kDNSServiceFlagsIncludeP2P flag
624 * to include P2P. In this case, if a service instance or the record being queried
625 * is found over P2P, the resulting ADD event will indicate kDNSServiceInterfaceIndexP2P
626 * as the interface index.
627 */
628
629#define kDNSServiceInterfaceIndexAny 0
630#define kDNSServiceInterfaceIndexLocalOnly ((uint32_t)-1)
631#define kDNSServiceInterfaceIndexUnicast   ((uint32_t)-2)
632#define kDNSServiceInterfaceIndexP2P       ((uint32_t)-3)
633
634typedef uint32_t DNSServiceFlags;
635typedef uint32_t DNSServiceProtocol;
636typedef int32_t  DNSServiceErrorType;
637
638
639/*********************************************************************************************
640 *
641 * Version checking
642 *
643 *********************************************************************************************/
644
645/* DNSServiceGetProperty() Parameters:
646 *
647 * property:        The requested property.
648 *                  Currently the only property defined is kDNSServiceProperty_DaemonVersion.
649 *
650 * result:          Place to store result.
651 *                  For retrieving DaemonVersion, this should be the address of a uint32_t.
652 *
653 * size:            Pointer to uint32_t containing size of the result location.
654 *                  For retrieving DaemonVersion, this should be sizeof(uint32_t).
655 *                  On return the uint32_t is updated to the size of the data returned.
656 *                  For DaemonVersion, the returned size is always sizeof(uint32_t), but
657 *                  future properties could be defined which return variable-sized results.
658 *
659 * return value:    Returns kDNSServiceErr_NoError on success, or kDNSServiceErr_ServiceNotRunning
660 *                  if the daemon (or "system service" on Windows) is not running.
661 */
662
663DNSServiceErrorType DNSSD_API DNSServiceGetProperty
664    (
665    const char *property,  /* Requested property (i.e. kDNSServiceProperty_DaemonVersion) */
666    void       *result,    /* Pointer to place to store result */
667    uint32_t   *size       /* size of result location */
668    );
669
670/*
671 * When requesting kDNSServiceProperty_DaemonVersion, the result pointer must point
672 * to a 32-bit unsigned integer, and the size parameter must be set to sizeof(uint32_t).
673 *
674 * On return, the 32-bit unsigned integer contains the version number, formatted as follows:
675 *   Major part of the build number * 10000 +
676 *   minor part of the build number *   100
677 *
678 * For example, Mac OS X 10.4.9 has mDNSResponder-108.4, which would be represented as
679 * version 1080400. This allows applications to do simple greater-than and less-than comparisons:
680 * e.g. an application that requires at least mDNSResponder-108.4 can check:
681 *
682 *   if (version >= 1080400) ...
683 *
684 * Example usage:
685 *
686 * uint32_t version;
687 * uint32_t size = sizeof(version);
688 * DNSServiceErrorType err = DNSServiceGetProperty(kDNSServiceProperty_DaemonVersion, &version, &size);
689 * if (!err) printf("Bonjour version is %d.%d\n", version / 10000, version / 100 % 100);
690 */
691
692#define kDNSServiceProperty_DaemonVersion "DaemonVersion"
693
694
695/*********************************************************************************************
696 *
697 * Unix Domain Socket access, DNSServiceRef deallocation, and data processing functions
698 *
699 *********************************************************************************************/
700
701/* DNSServiceRefSockFD()
702 *
703 * Access underlying Unix domain socket for an initialized DNSServiceRef.
704 * The DNS Service Discovery implementation uses this socket to communicate between the client and
705 * the mDNSResponder daemon. The application MUST NOT directly read from or write to this socket.
706 * Access to the socket is provided so that it can be used as a kqueue event source, a CFRunLoop
707 * event source, in a select() loop, etc. When the underlying event management subsystem (kqueue/
708 * select/CFRunLoop etc.) indicates to the client that data is available for reading on the
709 * socket, the client should call DNSServiceProcessResult(), which will extract the daemon's
710 * reply from the socket, and pass it to the appropriate application callback. By using a run
711 * loop or select(), results from the daemon can be processed asynchronously. Alternatively,
712 * a client can choose to fork a thread and have it loop calling "DNSServiceProcessResult(ref);"
713 * If DNSServiceProcessResult() is called when no data is available for reading on the socket, it
714 * will block until data does become available, and then process the data and return to the caller.
715 * When data arrives on the socket, the client is responsible for calling DNSServiceProcessResult(ref)
716 * in a timely fashion -- if the client allows a large backlog of data to build up the daemon
717 * may terminate the connection.
718 *
719 * sdRef:           A DNSServiceRef initialized by any of the DNSService calls.
720 *
721 * return value:    The DNSServiceRef's underlying socket descriptor, or -1 on
722 *                  error.
723 */
724
725int DNSSD_API DNSServiceRefSockFD(DNSServiceRef sdRef);
726
727
728/* DNSServiceProcessResult()
729 *
730 * Read a reply from the daemon, calling the appropriate application callback. This call will
731 * block until the daemon's response is received. Use DNSServiceRefSockFD() in
732 * conjunction with a run loop or select() to determine the presence of a response from the
733 * server before calling this function to process the reply without blocking. Call this function
734 * at any point if it is acceptable to block until the daemon's response arrives. Note that the
735 * client is responsible for ensuring that DNSServiceProcessResult() is called whenever there is
736 * a reply from the daemon - the daemon may terminate its connection with a client that does not
737 * process the daemon's responses.
738 *
739 * sdRef:           A DNSServiceRef initialized by any of the DNSService calls
740 *                  that take a callback parameter.
741 *
742 * return value:    Returns kDNSServiceErr_NoError on success, otherwise returns
743 *                  an error code indicating the specific failure that occurred.
744 */
745
746DNSServiceErrorType DNSSD_API DNSServiceProcessResult(DNSServiceRef sdRef);
747
748
749/* DNSServiceRefDeallocate()
750 *
751 * Terminate a connection with the daemon and free memory associated with the DNSServiceRef.
752 * Any services or records registered with this DNSServiceRef will be deregistered. Any
753 * Browse, Resolve, or Query operations called with this reference will be terminated.
754 *
755 * Note: If the reference's underlying socket is used in a run loop or select() call, it should
756 * be removed BEFORE DNSServiceRefDeallocate() is called, as this function closes the reference's
757 * socket.
758 *
759 * Note: If the reference was initialized with DNSServiceCreateConnection(), any DNSRecordRefs
760 * created via this reference will be invalidated by this call - the resource records are
761 * deregistered, and their DNSRecordRefs may not be used in subsequent functions. Similarly,
762 * if the reference was initialized with DNSServiceRegister, and an extra resource record was
763 * added to the service via DNSServiceAddRecord(), the DNSRecordRef created by the Add() call
764 * is invalidated when this function is called - the DNSRecordRef may not be used in subsequent
765 * functions.
766 *
767 * Note: This call is to be used only with the DNSServiceRef defined by this API. It is
768 * not compatible with dns_service_discovery_ref objects defined in the legacy Mach-based
769 * DNSServiceDiscovery.h API.
770 *
771 * sdRef:           A DNSServiceRef initialized by any of the DNSService calls.
772 *
773 */
774
775void DNSSD_API DNSServiceRefDeallocate(DNSServiceRef sdRef);
776
777
778/*********************************************************************************************
779 *
780 * Domain Enumeration
781 *
782 *********************************************************************************************/
783
784/* DNSServiceEnumerateDomains()
785 *
786 * Asynchronously enumerate domains available for browsing and registration.
787 *
788 * The enumeration MUST be cancelled via DNSServiceRefDeallocate() when no more domains
789 * are to be found.
790 *
791 * Note that the names returned are (like all of DNS-SD) UTF-8 strings,
792 * and are escaped using standard DNS escaping rules.
793 * (See "Notes on DNS Name Escaping" earlier in this file for more details.)
794 * A graphical browser displaying a hierarchical tree-structured view should cut
795 * the names at the bare dots to yield individual labels, then de-escape each
796 * label according to the escaping rules, and then display the resulting UTF-8 text.
797 *
798 * DNSServiceDomainEnumReply Callback Parameters:
799 *
800 * sdRef:           The DNSServiceRef initialized by DNSServiceEnumerateDomains().
801 *
802 * flags:           Possible values are:
803 *                  kDNSServiceFlagsMoreComing
804 *                  kDNSServiceFlagsAdd
805 *                  kDNSServiceFlagsDefault
806 *
807 * interfaceIndex:  Specifies the interface on which the domain exists. (The index for a given
808 *                  interface is determined via the if_nametoindex() family of calls.)
809 *
810 * errorCode:       Will be kDNSServiceErr_NoError (0) on success, otherwise indicates
811 *                  the failure that occurred (other parameters are undefined if errorCode is nonzero).
812 *
813 * replyDomain:     The name of the domain.
814 *
815 * context:         The context pointer passed to DNSServiceEnumerateDomains.
816 *
817 */
818
819typedef void (DNSSD_API *DNSServiceDomainEnumReply)
820    (
821    DNSServiceRef                       sdRef,
822    DNSServiceFlags                     flags,
823    uint32_t                            interfaceIndex,
824    DNSServiceErrorType                 errorCode,
825    const char                          *replyDomain,
826    void                                *context
827    );
828
829
830/* DNSServiceEnumerateDomains() Parameters:
831 *
832 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds
833 *                  then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError,
834 *                  and the enumeration operation will run indefinitely until the client
835 *                  terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate().
836 *
837 * flags:           Possible values are:
838 *                  kDNSServiceFlagsBrowseDomains to enumerate domains recommended for browsing.
839 *                  kDNSServiceFlagsRegistrationDomains to enumerate domains recommended
840 *                  for registration.
841 *
842 * interfaceIndex:  If non-zero, specifies the interface on which to look for domains.
843 *                  (the index for a given interface is determined via the if_nametoindex()
844 *                  family of calls.) Most applications will pass 0 to enumerate domains on
845 *                  all interfaces. See "Constants for specifying an interface index" for more details.
846 *
847 * callBack:        The function to be called when a domain is found or the call asynchronously
848 *                  fails.
849 *
850 * context:         An application context pointer which is passed to the callback function
851 *                  (may be NULL).
852 *
853 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
854 *                  errors are delivered to the callback), otherwise returns an error code indicating
855 *                  the error that occurred (the callback is not invoked and the DNSServiceRef
856 *                  is not initialized).
857 */
858
859DNSServiceErrorType DNSSD_API DNSServiceEnumerateDomains
860    (
861    DNSServiceRef                       *sdRef,
862    DNSServiceFlags                     flags,
863    uint32_t                            interfaceIndex,
864    DNSServiceDomainEnumReply           callBack,
865    void                                *context  /* may be NULL */
866    );
867
868
869/*********************************************************************************************
870 *
871 *  Service Registration
872 *
873 *********************************************************************************************/
874
875/* Register a service that is discovered via Browse() and Resolve() calls.
876 *
877 * DNSServiceRegisterReply() Callback Parameters:
878 *
879 * sdRef:           The DNSServiceRef initialized by DNSServiceRegister().
880 *
881 * flags:           When a name is successfully registered, the callback will be
882 *                  invoked with the kDNSServiceFlagsAdd flag set. When Wide-Area
883 *                  DNS-SD is in use, it is possible for a single service to get
884 *                  more than one success callback (e.g. one in the "local" multicast
885 *                  DNS domain, and another in a wide-area unicast DNS domain).
886 *                  If a successfully-registered name later suffers a name conflict
887 *                  or similar problem and has to be deregistered, the callback will
888 *                  be invoked with the kDNSServiceFlagsAdd flag not set. The callback
889 *                  is *not* invoked in the case where the caller explicitly terminates
890 *                  the service registration by calling DNSServiceRefDeallocate(ref);
891 *
892 * errorCode:       Will be kDNSServiceErr_NoError on success, otherwise will
893 *                  indicate the failure that occurred (including name conflicts,
894 *                  if the kDNSServiceFlagsNoAutoRename flag was used when registering.)
895 *                  Other parameters are undefined if errorCode is nonzero.
896 *
897 * name:            The service name registered (if the application did not specify a name in
898 *                  DNSServiceRegister(), this indicates what name was automatically chosen).
899 *
900 * regtype:         The type of service registered, as it was passed to the callout.
901 *
902 * domain:          The domain on which the service was registered (if the application did not
903 *                  specify a domain in DNSServiceRegister(), this indicates the default domain
904 *                  on which the service was registered).
905 *
906 * context:         The context pointer that was passed to the callout.
907 *
908 */
909
910typedef void (DNSSD_API *DNSServiceRegisterReply)
911    (
912    DNSServiceRef                       sdRef,
913    DNSServiceFlags                     flags,
914    DNSServiceErrorType                 errorCode,
915    const char                          *name,
916    const char                          *regtype,
917    const char                          *domain,
918    void                                *context
919    );
920
921
922/* DNSServiceRegister() Parameters:
923 *
924 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds
925 *                  then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError,
926 *                  and the registration will remain active indefinitely until the client
927 *                  terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate().
928 *
929 * interfaceIndex:  If non-zero, specifies the interface on which to register the service
930 *                  (the index for a given interface is determined via the if_nametoindex()
931 *                  family of calls.) Most applications will pass 0 to register on all
932 *                  available interfaces. See "Constants for specifying an interface index" for more details.
933 *
934 * flags:           Indicates the renaming behavior on name conflict (most applications
935 *                  will pass 0). See flag definitions above for details.
936 *
937 * name:            If non-NULL, specifies the service name to be registered.
938 *                  Most applications will not specify a name, in which case the computer
939 *                  name is used (this name is communicated to the client via the callback).
940 *                  If a name is specified, it must be 1-63 bytes of UTF-8 text.
941 *                  If the name is longer than 63 bytes it will be automatically truncated
942 *                  to a legal length, unless the NoAutoRename flag is set,
943 *                  in which case kDNSServiceErr_BadParam will be returned.
944 *
945 * regtype:         The service type followed by the protocol, separated by a dot
946 *                  (e.g. "_ftp._tcp"). The service type must be an underscore, followed
947 *                  by 1-15 characters, which may be letters, digits, or hyphens.
948 *                  The transport protocol must be "_tcp" or "_udp". New service types
949 *                  should be registered at <http://www.dns-sd.org/ServiceTypes.html>.
950 *
951 *                  Additional subtypes of the primary service type (where a service
952 *                  type has defined subtypes) follow the primary service type in a
953 *                  comma-separated list, with no additional spaces, e.g.
954 *                      "_primarytype._tcp,_subtype1,_subtype2,_subtype3"
955 *                  Subtypes provide a mechanism for filtered browsing: A client browsing
956 *                  for "_primarytype._tcp" will discover all instances of this type;
957 *                  a client browsing for "_primarytype._tcp,_subtype2" will discover only
958 *                  those instances that were registered with "_subtype2" in their list of
959 *                  registered subtypes.
960 *
961 *                  The subtype mechanism can be illustrated with some examples using the
962 *                  dns-sd command-line tool:
963 *
964 *                  % dns-sd -R Simple _test._tcp "" 1001 &
965 *                  % dns-sd -R Better _test._tcp,HasFeatureA "" 1002 &
966 *                  % dns-sd -R Best   _test._tcp,HasFeatureA,HasFeatureB "" 1003 &
967 *
968 *                  Now:
969 *                  % dns-sd -B _test._tcp             # will find all three services
970 *                  % dns-sd -B _test._tcp,HasFeatureA # finds "Better" and "Best"
971 *                  % dns-sd -B _test._tcp,HasFeatureB # finds only "Best"
972 *
973 *                  Subtype labels may be up to 63 bytes long, and may contain any eight-
974 *                  bit byte values, including zero bytes. However, due to the nature of
975 *                  using a C-string-based API, conventional DNS escaping must be used for
976 *                  dots ('.'), commas (','), backslashes ('\') and zero bytes, as shown below:
977 *
978 *                  % dns-sd -R Test '_test._tcp,s\.one,s\,two,s\\three,s\000four' local 123
979 *
980 * domain:          If non-NULL, specifies the domain on which to advertise the service.
981 *                  Most applications will not specify a domain, instead automatically
982 *                  registering in the default domain(s).
983 *
984 * host:            If non-NULL, specifies the SRV target host name. Most applications
985 *                  will not specify a host, instead automatically using the machine's
986 *                  default host name(s). Note that specifying a non-NULL host does NOT
987 *                  create an address record for that host - the application is responsible
988 *                  for ensuring that the appropriate address record exists, or creating it
989 *                  via DNSServiceRegisterRecord().
990 *
991 * port:            The port, in network byte order, on which the service accepts connections.
992 *                  Pass 0 for a "placeholder" service (i.e. a service that will not be discovered
993 *                  by browsing, but will cause a name conflict if another client tries to
994 *                  register that same name). Most clients will not use placeholder services.
995 *
996 * txtLen:          The length of the txtRecord, in bytes. Must be zero if the txtRecord is NULL.
997 *
998 * txtRecord:       The TXT record rdata. A non-NULL txtRecord MUST be a properly formatted DNS
999 *                  TXT record, i.e. <length byte> <data> <length byte> <data> ...
1000 *                  Passing NULL for the txtRecord is allowed as a synonym for txtLen=1, txtRecord="",
1001 *                  i.e. it creates a TXT record of length one containing a single empty string.
1002 *                  RFC 1035 doesn't allow a TXT record to contain *zero* strings, so a single empty
1003 *                  string is the smallest legal DNS TXT record.
1004 *                  As with the other parameters, the DNSServiceRegister call copies the txtRecord
1005 *                  data; e.g. if you allocated the storage for the txtRecord parameter with malloc()
1006 *                  then you can safely free that memory right after the DNSServiceRegister call returns.
1007 *
1008 * callBack:        The function to be called when the registration completes or asynchronously
1009 *                  fails. The client MAY pass NULL for the callback -  The client will NOT be notified
1010 *                  of the default values picked on its behalf, and the client will NOT be notified of any
1011 *                  asynchronous errors (e.g. out of memory errors, etc.) that may prevent the registration
1012 *                  of the service. The client may NOT pass the NoAutoRename flag if the callback is NULL.
1013 *                  The client may still deregister the service at any time via DNSServiceRefDeallocate().
1014 *
1015 * context:         An application context pointer which is passed to the callback function
1016 *                  (may be NULL).
1017 *
1018 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1019 *                  errors are delivered to the callback), otherwise returns an error code indicating
1020 *                  the error that occurred (the callback is never invoked and the DNSServiceRef
1021 *                  is not initialized).
1022 */
1023
1024DNSServiceErrorType DNSSD_API DNSServiceRegister
1025    (
1026    DNSServiceRef                       *sdRef,
1027    DNSServiceFlags                     flags,
1028    uint32_t                            interfaceIndex,
1029    const char                          *name,         /* may be NULL */
1030    const char                          *regtype,
1031    const char                          *domain,       /* may be NULL */
1032    const char                          *host,         /* may be NULL */
1033    uint16_t                            port,          /* In network byte order */
1034    uint16_t                            txtLen,
1035    const void                          *txtRecord,    /* may be NULL */
1036    DNSServiceRegisterReply             callBack,      /* may be NULL */
1037    void                                *context       /* may be NULL */
1038    );
1039
1040
1041/* DNSServiceAddRecord()
1042 *
1043 * Add a record to a registered service. The name of the record will be the same as the
1044 * registered service's name.
1045 * The record can later be updated or deregistered by passing the RecordRef initialized
1046 * by this function to DNSServiceUpdateRecord() or DNSServiceRemoveRecord().
1047 *
1048 * Note that the DNSServiceAddRecord/UpdateRecord/RemoveRecord are *NOT* thread-safe
1049 * with respect to a single DNSServiceRef. If you plan to have multiple threads
1050 * in your program simultaneously add, update, or remove records from the same
1051 * DNSServiceRef, then it's the caller's responsibility to use a mutext lock
1052 * or take similar appropriate precautions to serialize those calls.
1053 *
1054 * Parameters;
1055 *
1056 * sdRef:           A DNSServiceRef initialized by DNSServiceRegister().
1057 *
1058 * RecordRef:       A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this
1059 *                  call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord().
1060 *                  If the above DNSServiceRef is passed to DNSServiceRefDeallocate(), RecordRef is also
1061 *                  invalidated and may not be used further.
1062 *
1063 * flags:           Currently ignored, reserved for future use.
1064 *
1065 * rrtype:          The type of the record (e.g. kDNSServiceType_TXT, kDNSServiceType_SRV, etc)
1066 *
1067 * rdlen:           The length, in bytes, of the rdata.
1068 *
1069 * rdata:           The raw rdata to be contained in the added resource record.
1070 *
1071 * ttl:             The time to live of the resource record, in seconds.
1072 *                  Most clients should pass 0 to indicate that the system should
1073 *                  select a sensible default value.
1074 *
1075 * return value:    Returns kDNSServiceErr_NoError on success, otherwise returns an
1076 *                  error code indicating the error that occurred (the RecordRef is not initialized).
1077 */
1078
1079DNSServiceErrorType DNSSD_API DNSServiceAddRecord
1080    (
1081    DNSServiceRef                       sdRef,
1082    DNSRecordRef                        *RecordRef,
1083    DNSServiceFlags                     flags,
1084    uint16_t                            rrtype,
1085    uint16_t                            rdlen,
1086    const void                          *rdata,
1087    uint32_t                            ttl
1088    );
1089
1090
1091/* DNSServiceUpdateRecord
1092 *
1093 * Update a registered resource record. The record must either be:
1094 *   - The primary txt record of a service registered via DNSServiceRegister()
1095 *   - A record added to a registered service via DNSServiceAddRecord()
1096 *   - An individual record registered by DNSServiceRegisterRecord()
1097 *
1098 * Parameters:
1099 *
1100 * sdRef:           A DNSServiceRef that was initialized by DNSServiceRegister()
1101 *                  or DNSServiceCreateConnection().
1102 *
1103 * RecordRef:       A DNSRecordRef initialized by DNSServiceAddRecord, or NULL to update the
1104 *                  service's primary txt record.
1105 *
1106 * flags:           Currently ignored, reserved for future use.
1107 *
1108 * rdlen:           The length, in bytes, of the new rdata.
1109 *
1110 * rdata:           The new rdata to be contained in the updated resource record.
1111 *
1112 * ttl:             The time to live of the updated resource record, in seconds.
1113 *                  Most clients should pass 0 to indicate that the system should
1114 *                  select a sensible default value.
1115 *
1116 * return value:    Returns kDNSServiceErr_NoError on success, otherwise returns an
1117 *                  error code indicating the error that occurred.
1118 */
1119
1120DNSServiceErrorType DNSSD_API DNSServiceUpdateRecord
1121    (
1122    DNSServiceRef                       sdRef,
1123    DNSRecordRef                        RecordRef,     /* may be NULL */
1124    DNSServiceFlags                     flags,
1125    uint16_t                            rdlen,
1126    const void                          *rdata,
1127    uint32_t                            ttl
1128    );
1129
1130
1131/* DNSServiceRemoveRecord
1132 *
1133 * Remove a record previously added to a service record set via DNSServiceAddRecord(), or deregister
1134 * an record registered individually via DNSServiceRegisterRecord().
1135 *
1136 * Parameters:
1137 *
1138 * sdRef:           A DNSServiceRef initialized by DNSServiceRegister() (if the
1139 *                  record being removed was registered via DNSServiceAddRecord()) or by
1140 *                  DNSServiceCreateConnection() (if the record being removed was registered via
1141 *                  DNSServiceRegisterRecord()).
1142 *
1143 * recordRef:       A DNSRecordRef initialized by a successful call to DNSServiceAddRecord()
1144 *                  or DNSServiceRegisterRecord().
1145 *
1146 * flags:           Currently ignored, reserved for future use.
1147 *
1148 * return value:    Returns kDNSServiceErr_NoError on success, otherwise returns an
1149 *                  error code indicating the error that occurred.
1150 */
1151
1152DNSServiceErrorType DNSSD_API DNSServiceRemoveRecord
1153    (
1154    DNSServiceRef                 sdRef,
1155    DNSRecordRef                  RecordRef,
1156    DNSServiceFlags               flags
1157    );
1158
1159
1160/*********************************************************************************************
1161 *
1162 *  Service Discovery
1163 *
1164 *********************************************************************************************/
1165
1166/* Browse for instances of a service.
1167 *
1168 * DNSServiceBrowseReply() Parameters:
1169 *
1170 * sdRef:           The DNSServiceRef initialized by DNSServiceBrowse().
1171 *
1172 * flags:           Possible values are kDNSServiceFlagsMoreComing and kDNSServiceFlagsAdd.
1173 *                  See flag definitions for details.
1174 *
1175 * interfaceIndex:  The interface on which the service is advertised. This index should
1176 *                  be passed to DNSServiceResolve() when resolving the service.
1177 *
1178 * errorCode:       Will be kDNSServiceErr_NoError (0) on success, otherwise will
1179 *                  indicate the failure that occurred. Other parameters are undefined if
1180 *                  the errorCode is nonzero.
1181 *
1182 * serviceName:     The discovered service name. This name should be displayed to the user,
1183 *                  and stored for subsequent use in the DNSServiceResolve() call.
1184 *
1185 * regtype:         The service type, which is usually (but not always) the same as was passed
1186 *                  to DNSServiceBrowse(). One case where the discovered service type may
1187 *                  not be the same as the requested service type is when using subtypes:
1188 *                  The client may want to browse for only those ftp servers that allow
1189 *                  anonymous connections. The client will pass the string "_ftp._tcp,_anon"
1190 *                  to DNSServiceBrowse(), but the type of the service that's discovered
1191 *                  is simply "_ftp._tcp". The regtype for each discovered service instance
1192 *                  should be stored along with the name, so that it can be passed to
1193 *                  DNSServiceResolve() when the service is later resolved.
1194 *
1195 * domain:          The domain of the discovered service instance. This may or may not be the
1196 *                  same as the domain that was passed to DNSServiceBrowse(). The domain for each
1197 *                  discovered service instance should be stored along with the name, so that
1198 *                  it can be passed to DNSServiceResolve() when the service is later resolved.
1199 *
1200 * context:         The context pointer that was passed to the callout.
1201 *
1202 */
1203
1204typedef void (DNSSD_API *DNSServiceBrowseReply)
1205    (
1206    DNSServiceRef                       sdRef,
1207    DNSServiceFlags                     flags,
1208    uint32_t                            interfaceIndex,
1209    DNSServiceErrorType                 errorCode,
1210    const char                          *serviceName,
1211    const char                          *regtype,
1212    const char                          *replyDomain,
1213    void                                *context
1214    );
1215
1216
1217/* DNSServiceBrowse() Parameters:
1218 *
1219 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds
1220 *                  then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError,
1221 *                  and the browse operation will run indefinitely until the client
1222 *                  terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate().
1223 *
1224 * flags:           Currently ignored, reserved for future use.
1225 *
1226 * interfaceIndex:  If non-zero, specifies the interface on which to browse for services
1227 *                  (the index for a given interface is determined via the if_nametoindex()
1228 *                  family of calls.) Most applications will pass 0 to browse on all available
1229 *                  interfaces. See "Constants for specifying an interface index" for more details.
1230 *
1231 * regtype:         The service type being browsed for followed by the protocol, separated by a
1232 *                  dot (e.g. "_ftp._tcp"). The transport protocol must be "_tcp" or "_udp".
1233 *                  A client may optionally specify a single subtype to perform filtered browsing:
1234 *                  e.g. browsing for "_primarytype._tcp,_subtype" will discover only those
1235 *                  instances of "_primarytype._tcp" that were registered specifying "_subtype"
1236 *                  in their list of registered subtypes.
1237 *
1238 * domain:          If non-NULL, specifies the domain on which to browse for services.
1239 *                  Most applications will not specify a domain, instead browsing on the
1240 *                  default domain(s).
1241 *
1242 * callBack:        The function to be called when an instance of the service being browsed for
1243 *                  is found, or if the call asynchronously fails.
1244 *
1245 * context:         An application context pointer which is passed to the callback function
1246 *                  (may be NULL).
1247 *
1248 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1249 *                  errors are delivered to the callback), otherwise returns an error code indicating
1250 *                  the error that occurred (the callback is not invoked and the DNSServiceRef
1251 *                  is not initialized).
1252 */
1253
1254DNSServiceErrorType DNSSD_API DNSServiceBrowse
1255    (
1256    DNSServiceRef                       *sdRef,
1257    DNSServiceFlags                     flags,
1258    uint32_t                            interfaceIndex,
1259    const char                          *regtype,
1260    const char                          *domain,    /* may be NULL */
1261    DNSServiceBrowseReply               callBack,
1262    void                                *context    /* may be NULL */
1263    );
1264
1265
1266/* DNSServiceResolve()
1267 *
1268 * Resolve a service name discovered via DNSServiceBrowse() to a target host name, port number, and
1269 * txt record.
1270 *
1271 * Note: Applications should NOT use DNSServiceResolve() solely for txt record monitoring - use
1272 * DNSServiceQueryRecord() instead, as it is more efficient for this task.
1273 *
1274 * Note: When the desired results have been returned, the client MUST terminate the resolve by calling
1275 * DNSServiceRefDeallocate().
1276 *
1277 * Note: DNSServiceResolve() behaves correctly for typical services that have a single SRV record
1278 * and a single TXT record. To resolve non-standard services with multiple SRV or TXT records,
1279 * DNSServiceQueryRecord() should be used.
1280 *
1281 * DNSServiceResolveReply Callback Parameters:
1282 *
1283 * sdRef:           The DNSServiceRef initialized by DNSServiceResolve().
1284 *
1285 * flags:           Possible values: kDNSServiceFlagsMoreComing
1286 *
1287 * interfaceIndex:  The interface on which the service was resolved.
1288 *
1289 * errorCode:       Will be kDNSServiceErr_NoError (0) on success, otherwise will
1290 *                  indicate the failure that occurred. Other parameters are undefined if
1291 *                  the errorCode is nonzero.
1292 *
1293 * fullname:        The full service domain name, in the form <servicename>.<protocol>.<domain>.
1294 *                  (This name is escaped following standard DNS rules, making it suitable for
1295 *                  passing to standard system DNS APIs such as res_query(), or to the
1296 *                  special-purpose functions included in this API that take fullname parameters.
1297 *                  See "Notes on DNS Name Escaping" earlier in this file for more details.)
1298 *
1299 * hosttarget:      The target hostname of the machine providing the service. This name can
1300 *                  be passed to functions like gethostbyname() to identify the host's IP address.
1301 *
1302 * port:            The port, in network byte order, on which connections are accepted for this service.
1303 *
1304 * txtLen:          The length of the txt record, in bytes.
1305 *
1306 * txtRecord:       The service's primary txt record, in standard txt record format.
1307 *
1308 * context:         The context pointer that was passed to the callout.
1309 *
1310 * NOTE: In earlier versions of this header file, the txtRecord parameter was declared "const char *"
1311 * This is incorrect, since it contains length bytes which are values in the range 0 to 255, not -128 to +127.
1312 * Depending on your compiler settings, this change may cause signed/unsigned mismatch warnings.
1313 * These should be fixed by updating your own callback function definition to match the corrected
1314 * function signature using "const unsigned char *txtRecord". Making this change may also fix inadvertent
1315 * bugs in your callback function, where it could have incorrectly interpreted a length byte with value 250
1316 * as being -6 instead, with various bad consequences ranging from incorrect operation to software crashes.
1317 * If you need to maintain portable code that will compile cleanly with both the old and new versions of
1318 * this header file, you should update your callback function definition to use the correct unsigned value,
1319 * and then in the place where you pass your callback function to DNSServiceResolve(), use a cast to eliminate
1320 * the compiler warning, e.g.:
1321 *   DNSServiceResolve(sd, flags, index, name, regtype, domain, (DNSServiceResolveReply)MyCallback, context);
1322 * This will ensure that your code compiles cleanly without warnings (and more importantly, works correctly)
1323 * with both the old header and with the new corrected version.
1324 *
1325 */
1326
1327typedef void (DNSSD_API *DNSServiceResolveReply)
1328    (
1329    DNSServiceRef                       sdRef,
1330    DNSServiceFlags                     flags,
1331    uint32_t                            interfaceIndex,
1332    DNSServiceErrorType                 errorCode,
1333    const char                          *fullname,
1334    const char                          *hosttarget,
1335    uint16_t                            port,        /* In network byte order */
1336    uint16_t                            txtLen,
1337    const unsigned char                 *txtRecord,
1338    void                                *context
1339    );
1340
1341
1342/* DNSServiceResolve() Parameters
1343 *
1344 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds
1345 *                  then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError,
1346 *                  and the resolve operation will run indefinitely until the client
1347 *                  terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate().
1348 *
1349 * flags:           Specifying kDNSServiceFlagsForceMulticast will cause query to be
1350 *                  performed with a link-local mDNS query, even if the name is an
1351 *                  apparently non-local name (i.e. a name not ending in ".local.")
1352 *
1353 * interfaceIndex:  The interface on which to resolve the service. If this resolve call is
1354 *                  as a result of a currently active DNSServiceBrowse() operation, then the
1355 *                  interfaceIndex should be the index reported in the DNSServiceBrowseReply
1356 *                  callback. If this resolve call is using information previously saved
1357 *                  (e.g. in a preference file) for later use, then use interfaceIndex 0, because
1358 *                  the desired service may now be reachable via a different physical interface.
1359 *                  See "Constants for specifying an interface index" for more details.
1360 *
1361 * name:            The name of the service instance to be resolved, as reported to the
1362 *                  DNSServiceBrowseReply() callback.
1363 *
1364 * regtype:         The type of the service instance to be resolved, as reported to the
1365 *                  DNSServiceBrowseReply() callback.
1366 *
1367 * domain:          The domain of the service instance to be resolved, as reported to the
1368 *                  DNSServiceBrowseReply() callback.
1369 *
1370 * callBack:        The function to be called when a result is found, or if the call
1371 *                  asynchronously fails.
1372 *
1373 * context:         An application context pointer which is passed to the callback function
1374 *                  (may be NULL).
1375 *
1376 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1377 *                  errors are delivered to the callback), otherwise returns an error code indicating
1378 *                  the error that occurred (the callback is never invoked and the DNSServiceRef
1379 *                  is not initialized).
1380 */
1381
1382DNSServiceErrorType DNSSD_API DNSServiceResolve
1383    (
1384    DNSServiceRef                       *sdRef,
1385    DNSServiceFlags                     flags,
1386    uint32_t                            interfaceIndex,
1387    const char                          *name,
1388    const char                          *regtype,
1389    const char                          *domain,
1390    DNSServiceResolveReply              callBack,
1391    void                                *context  /* may be NULL */
1392    );
1393
1394
1395/*********************************************************************************************
1396 *
1397 *  Querying Individual Specific Records
1398 *
1399 *********************************************************************************************/
1400
1401/* DNSServiceQueryRecord
1402 *
1403 * Query for an arbitrary DNS record.
1404 *
1405 * DNSServiceQueryRecordReply() Callback Parameters:
1406 *
1407 * sdRef:           The DNSServiceRef initialized by DNSServiceQueryRecord().
1408 *
1409 * flags:           Possible values are kDNSServiceFlagsMoreComing and
1410 *                  kDNSServiceFlagsAdd. The Add flag is NOT set for PTR records
1411 *                  with a ttl of 0, i.e. "Remove" events.
1412 *
1413 * interfaceIndex:  The interface on which the query was resolved (the index for a given
1414 *                  interface is determined via the if_nametoindex() family of calls).
1415 *                  See "Constants for specifying an interface index" for more details.
1416 *
1417 * errorCode:       Will be kDNSServiceErr_NoError on success, otherwise will
1418 *                  indicate the failure that occurred. Other parameters are undefined if
1419 *                  errorCode is nonzero.
1420 *
1421 * fullname:        The resource record's full domain name.
1422 *
1423 * rrtype:          The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc)
1424 *
1425 * rrclass:         The class of the resource record (usually kDNSServiceClass_IN).
1426 *
1427 * rdlen:           The length, in bytes, of the resource record rdata.
1428 *
1429 * rdata:           The raw rdata of the resource record.
1430 *
1431 * ttl:             If the client wishes to cache the result for performance reasons,
1432 *                  the TTL indicates how long the client may legitimately hold onto
1433 *                  this result, in seconds. After the TTL expires, the client should
1434 *                  consider the result no longer valid, and if it requires this data
1435 *                  again, it should be re-fetched with a new query. Of course, this
1436 *                  only applies to clients that cancel the asynchronous operation when
1437 *                  they get a result. Clients that leave the asynchronous operation
1438 *                  running can safely assume that the data remains valid until they
1439 *                  get another callback telling them otherwise.
1440 *
1441 * context:         The context pointer that was passed to the callout.
1442 *
1443 */
1444
1445typedef void (DNSSD_API *DNSServiceQueryRecordReply)
1446    (
1447    DNSServiceRef                       sdRef,
1448    DNSServiceFlags                     flags,
1449    uint32_t                            interfaceIndex,
1450    DNSServiceErrorType                 errorCode,
1451    const char                          *fullname,
1452    uint16_t                            rrtype,
1453    uint16_t                            rrclass,
1454    uint16_t                            rdlen,
1455    const void                          *rdata,
1456    uint32_t                            ttl,
1457    void                                *context
1458    );
1459
1460
1461/* DNSServiceQueryRecord() Parameters:
1462 *
1463 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds
1464 *                  then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError,
1465 *                  and the query operation will run indefinitely until the client
1466 *                  terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate().
1467 *
1468 * flags:           kDNSServiceFlagsForceMulticast or kDNSServiceFlagsLongLivedQuery.
1469 *                  Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast
1470 *                  query in a non-local domain. Without setting this flag, unicast queries
1471 *                  will be one-shot - that is, only answers available at the time of the call
1472 *                  will be returned. By setting this flag, answers (including Add and Remove
1473 *                  events) that become available after the initial call is made will generate
1474 *                  callbacks. This flag has no effect on link-local multicast queries.
1475 *
1476 * interfaceIndex:  If non-zero, specifies the interface on which to issue the query
1477 *                  (the index for a given interface is determined via the if_nametoindex()
1478 *                  family of calls.) Passing 0 causes the name to be queried for on all
1479 *                  interfaces. See "Constants for specifying an interface index" for more details.
1480 *
1481 * fullname:        The full domain name of the resource record to be queried for.
1482 *
1483 * rrtype:          The numerical type of the resource record to be queried for
1484 *                  (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc)
1485 *
1486 * rrclass:         The class of the resource record (usually kDNSServiceClass_IN).
1487 *
1488 * callBack:        The function to be called when a result is found, or if the call
1489 *                  asynchronously fails.
1490 *
1491 * context:         An application context pointer which is passed to the callback function
1492 *                  (may be NULL).
1493 *
1494 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1495 *                  errors are delivered to the callback), otherwise returns an error code indicating
1496 *                  the error that occurred (the callback is never invoked and the DNSServiceRef
1497 *                  is not initialized).
1498 */
1499
1500DNSServiceErrorType DNSSD_API DNSServiceQueryRecord
1501    (
1502    DNSServiceRef                       *sdRef,
1503    DNSServiceFlags                     flags,
1504    uint32_t                            interfaceIndex,
1505    const char                          *fullname,
1506    uint16_t                            rrtype,
1507    uint16_t                            rrclass,
1508    DNSServiceQueryRecordReply          callBack,
1509    void                                *context  /* may be NULL */
1510    );
1511
1512
1513/*********************************************************************************************
1514 *
1515 *  Unified lookup of both IPv4 and IPv6 addresses for a fully qualified hostname
1516 *
1517 *********************************************************************************************/
1518
1519/* DNSServiceGetAddrInfo
1520 *
1521 * Queries for the IP address of a hostname by using either Multicast or Unicast DNS.
1522 *
1523 * DNSServiceGetAddrInfoReply() parameters:
1524 *
1525 * sdRef:           The DNSServiceRef initialized by DNSServiceGetAddrInfo().
1526 *
1527 * flags:           Possible values are kDNSServiceFlagsMoreComing and
1528 *                  kDNSServiceFlagsAdd.
1529 *
1530 * interfaceIndex:  The interface to which the answers pertain.
1531 *
1532 * errorCode:       Will be kDNSServiceErr_NoError on success, otherwise will
1533 *                  indicate the failure that occurred.  Other parameters are
1534 *                  undefined if errorCode is nonzero.
1535 *
1536 * hostname:        The fully qualified domain name of the host to be queried for.
1537 *
1538 * address:         IPv4 or IPv6 address.
1539 *
1540 * ttl:             If the client wishes to cache the result for performance reasons,
1541 *                  the TTL indicates how long the client may legitimately hold onto
1542 *                  this result, in seconds. After the TTL expires, the client should
1543 *                  consider the result no longer valid, and if it requires this data
1544 *                  again, it should be re-fetched with a new query. Of course, this
1545 *                  only applies to clients that cancel the asynchronous operation when
1546 *                  they get a result. Clients that leave the asynchronous operation
1547 *                  running can safely assume that the data remains valid until they
1548 *                  get another callback telling them otherwise.
1549 *
1550 * context:         The context pointer that was passed to the callout.
1551 *
1552 */
1553
1554typedef void (DNSSD_API *DNSServiceGetAddrInfoReply)
1555    (
1556    DNSServiceRef                    sdRef,
1557    DNSServiceFlags                  flags,
1558    uint32_t                         interfaceIndex,
1559    DNSServiceErrorType              errorCode,
1560    const char                       *hostname,
1561    const struct sockaddr            *address,
1562    uint32_t                         ttl,
1563    void                             *context
1564    );
1565
1566
1567/* DNSServiceGetAddrInfo() Parameters:
1568 *
1569 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds then it
1570 *                  initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the query
1571 *                  begins and will last indefinitely until the client terminates the query
1572 *                  by passing this DNSServiceRef to DNSServiceRefDeallocate().
1573 *
1574 * flags:           kDNSServiceFlagsForceMulticast or kDNSServiceFlagsLongLivedQuery.
1575 *                  Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast
1576 *                  query in a non-local domain. Without setting this flag, unicast queries
1577 *                  will be one-shot - that is, only answers available at the time of the call
1578 *                  will be returned. By setting this flag, answers (including Add and Remove
1579 *                  events) that become available after the initial call is made will generate
1580 *                  callbacks. This flag has no effect on link-local multicast queries.
1581 *
1582 * interfaceIndex:  The interface on which to issue the query.  Passing 0 causes the query to be
1583 *                  sent on all active interfaces via Multicast or the primary interface via Unicast.
1584 *
1585 * protocol:        Pass in kDNSServiceProtocol_IPv4 to look up IPv4 addresses, or kDNSServiceProtocol_IPv6
1586 *                  to look up IPv6 addresses, or both to look up both kinds. If neither flag is
1587 *                  set, the system will apply an intelligent heuristic, which is (currently)
1588 *                  that it will attempt to look up both, except:
1589 *
1590 *                   * If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name)
1591 *                     but this host has no routable IPv6 address, then the call will not try to
1592 *                     look up IPv6 addresses for "hostname", since any addresses it found would be
1593 *                     unlikely to be of any use anyway. Similarly, if this host has no routable
1594 *                     IPv4 address, the call will not try to look up IPv4 addresses for "hostname".
1595 *
1596 * hostname:        The fully qualified domain name of the host to be queried for.
1597 *
1598 * callBack:        The function to be called when the query succeeds or fails asynchronously.
1599 *
1600 * context:         An application context pointer which is passed to the callback function
1601 *                  (may be NULL).
1602 *
1603 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1604 *                  errors are delivered to the callback), otherwise returns an error code indicating
1605 *                  the error that occurred.
1606 */
1607
1608DNSServiceErrorType DNSSD_API DNSServiceGetAddrInfo
1609    (
1610    DNSServiceRef                    *sdRef,
1611    DNSServiceFlags                  flags,
1612    uint32_t                         interfaceIndex,
1613    DNSServiceProtocol               protocol,
1614    const char                       *hostname,
1615    DNSServiceGetAddrInfoReply       callBack,
1616    void                             *context          /* may be NULL */
1617    );
1618
1619
1620/*********************************************************************************************
1621 *
1622 *  Special Purpose Calls:
1623 *  DNSServiceCreateConnection(), DNSServiceRegisterRecord(), DNSServiceReconfirmRecord()
1624 *  (most applications will not use these)
1625 *
1626 *********************************************************************************************/
1627
1628/* DNSServiceCreateConnection()
1629 *
1630 * Create a connection to the daemon allowing efficient registration of
1631 * multiple individual records.
1632 *
1633 * Parameters:
1634 *
1635 * sdRef:           A pointer to an uninitialized DNSServiceRef. Deallocating
1636 *                  the reference (via DNSServiceRefDeallocate()) severs the
1637 *                  connection and deregisters all records registered on this connection.
1638 *
1639 * return value:    Returns kDNSServiceErr_NoError on success, otherwise returns
1640 *                  an error code indicating the specific failure that occurred (in which
1641 *                  case the DNSServiceRef is not initialized).
1642 */
1643
1644DNSServiceErrorType DNSSD_API DNSServiceCreateConnection(DNSServiceRef *sdRef);
1645
1646
1647/* DNSServiceRegisterRecord
1648 *
1649 * Register an individual resource record on a connected DNSServiceRef.
1650 *
1651 * Note that name conflicts occurring for records registered via this call must be handled
1652 * by the client in the callback.
1653 *
1654 * DNSServiceRegisterRecordReply() parameters:
1655 *
1656 * sdRef:           The connected DNSServiceRef initialized by
1657 *                  DNSServiceCreateConnection().
1658 *
1659 * RecordRef:       The DNSRecordRef initialized by DNSServiceRegisterRecord(). If the above
1660 *                  DNSServiceRef is passed to DNSServiceRefDeallocate(), this DNSRecordRef is
1661 *                  invalidated, and may not be used further.
1662 *
1663 * flags:           Currently unused, reserved for future use.
1664 *
1665 * errorCode:       Will be kDNSServiceErr_NoError on success, otherwise will
1666 *                  indicate the failure that occurred (including name conflicts.)
1667 *                  Other parameters are undefined if errorCode is nonzero.
1668 *
1669 * context:         The context pointer that was passed to the callout.
1670 *
1671 */
1672
1673 typedef void (DNSSD_API *DNSServiceRegisterRecordReply)
1674    (
1675    DNSServiceRef                       sdRef,
1676    DNSRecordRef                        RecordRef,
1677    DNSServiceFlags                     flags,
1678    DNSServiceErrorType                 errorCode,
1679    void                                *context
1680    );
1681
1682
1683/* DNSServiceRegisterRecord() Parameters:
1684 *
1685 * sdRef:           A DNSServiceRef initialized by DNSServiceCreateConnection().
1686 *
1687 * RecordRef:       A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this
1688 *                  call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord().
1689 *                  (To deregister ALL records registered on a single connected DNSServiceRef
1690 *                  and deallocate each of their corresponding DNSServiceRecordRefs, call
1691 *                  DNSServiceRefDeallocate()).
1692 *
1693 * flags:           Possible values are kDNSServiceFlagsShared or kDNSServiceFlagsUnique
1694 *                  (see flag type definitions for details).
1695 *
1696 * interfaceIndex:  If non-zero, specifies the interface on which to register the record
1697 *                  (the index for a given interface is determined via the if_nametoindex()
1698 *                  family of calls.) Passing 0 causes the record to be registered on all interfaces.
1699 *                  See "Constants for specifying an interface index" for more details.
1700 *
1701 * fullname:        The full domain name of the resource record.
1702 *
1703 * rrtype:          The numerical type of the resource record (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc)
1704 *
1705 * rrclass:         The class of the resource record (usually kDNSServiceClass_IN)
1706 *
1707 * rdlen:           Length, in bytes, of the rdata.
1708 *
1709 * rdata:           A pointer to the raw rdata, as it is to appear in the DNS record.
1710 *
1711 * ttl:             The time to live of the resource record, in seconds.
1712 *                  Most clients should pass 0 to indicate that the system should
1713 *                  select a sensible default value.
1714 *
1715 * callBack:        The function to be called when a result is found, or if the call
1716 *                  asynchronously fails (e.g. because of a name conflict.)
1717 *
1718 * context:         An application context pointer which is passed to the callback function
1719 *                  (may be NULL).
1720 *
1721 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1722 *                  errors are delivered to the callback), otherwise returns an error code indicating
1723 *                  the error that occurred (the callback is never invoked and the DNSRecordRef is
1724 *                  not initialized).
1725 */
1726
1727DNSServiceErrorType DNSSD_API DNSServiceRegisterRecord
1728    (
1729    DNSServiceRef                       sdRef,
1730    DNSRecordRef                        *RecordRef,
1731    DNSServiceFlags                     flags,
1732    uint32_t                            interfaceIndex,
1733    const char                          *fullname,
1734    uint16_t                            rrtype,
1735    uint16_t                            rrclass,
1736    uint16_t                            rdlen,
1737    const void                          *rdata,
1738    uint32_t                            ttl,
1739    DNSServiceRegisterRecordReply       callBack,
1740    void                                *context    /* may be NULL */
1741    );
1742
1743
1744/* DNSServiceReconfirmRecord
1745 *
1746 * Instruct the daemon to verify the validity of a resource record that appears
1747 * to be out of date (e.g. because TCP connection to a service's target failed.)
1748 * Causes the record to be flushed from the daemon's cache (as well as all other
1749 * daemons' caches on the network) if the record is determined to be invalid.
1750 * Use this routine conservatively. Reconfirming a record necessarily consumes
1751 * network bandwidth, so this should not be done indiscriminately.
1752 *
1753 * Parameters:
1754 *
1755 * flags:           Pass kDNSServiceFlagsForce to force immediate deletion of record,
1756 *                  instead of after some number of reconfirmation queries have gone unanswered.
1757 *
1758 * interfaceIndex:  Specifies the interface of the record in question.
1759 *                  The caller must specify the interface.
1760 *                  This API (by design) causes increased network traffic, so it requires
1761 *                  the caller to be precise about which record should be reconfirmed.
1762 *                  It is not possible to pass zero for the interface index to perform
1763 *                  a "wildcard" reconfirmation, where *all* matching records are reconfirmed.
1764 *
1765 * fullname:        The resource record's full domain name.
1766 *
1767 * rrtype:          The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc)
1768 *
1769 * rrclass:         The class of the resource record (usually kDNSServiceClass_IN).
1770 *
1771 * rdlen:           The length, in bytes, of the resource record rdata.
1772 *
1773 * rdata:           The raw rdata of the resource record.
1774 *
1775 */
1776
1777DNSServiceErrorType DNSSD_API DNSServiceReconfirmRecord
1778    (
1779    DNSServiceFlags                    flags,
1780    uint32_t                           interfaceIndex,
1781    const char                         *fullname,
1782    uint16_t                           rrtype,
1783    uint16_t                           rrclass,
1784    uint16_t                           rdlen,
1785    const void                         *rdata
1786    );
1787
1788
1789/*********************************************************************************************
1790 *
1791 *  NAT Port Mapping
1792 *
1793 *********************************************************************************************/
1794
1795/* DNSServiceNATPortMappingCreate
1796 *
1797 * Request a port mapping in the NAT gateway, which maps a port on the local machine
1798 * to an external port on the NAT. The NAT should support either the NAT-PMP or the UPnP IGD
1799 * protocol for this API to create a successful mapping.
1800 *
1801 * The port mapping will be renewed indefinitely until the client process exits, or
1802 * explicitly terminates the port mapping request by calling DNSServiceRefDeallocate().
1803 * The client callback will be invoked, informing the client of the NAT gateway's
1804 * external IP address and the external port that has been allocated for this client.
1805 * The client should then record this external IP address and port using whatever
1806 * directory service mechanism it is using to enable peers to connect to it.
1807 * (Clients advertising services using Wide-Area DNS-SD DO NOT need to use this API
1808 * -- when a client calls DNSServiceRegister() NAT mappings are automatically created
1809 * and the external IP address and port for the service are recorded in the global DNS.
1810 * Only clients using some directory mechanism other than Wide-Area DNS-SD need to use
1811 * this API to explicitly map their own ports.)
1812 *
1813 * It's possible that the client callback could be called multiple times, for example
1814 * if the NAT gateway's IP address changes, or if a configuration change results in a
1815 * different external port being mapped for this client. Over the lifetime of any long-lived
1816 * port mapping, the client should be prepared to handle these notifications of changes
1817 * in the environment, and should update its recorded address and/or port as appropriate.
1818 *
1819 * NOTE: There are two unusual aspects of how the DNSServiceNATPortMappingCreate API works,
1820 * which were intentionally designed to help simplify client code:
1821 *
1822 *  1. It's not an error to request a NAT mapping when the machine is not behind a NAT gateway.
1823 *     In other NAT mapping APIs, if you request a NAT mapping and the machine is not behind a NAT
1824 *     gateway, then the API returns an error code -- it can't get you a NAT mapping if there's no
1825 *     NAT gateway. The DNSServiceNATPortMappingCreate API takes a different view. Working out
1826 *     whether or not you need a NAT mapping can be tricky and non-obvious, particularly on
1827 *     a machine with multiple active network interfaces. Rather than make every client recreate
1828 *     this logic for deciding whether a NAT mapping is required, the PortMapping API does that
1829 *     work for you. If the client calls the PortMapping API when the machine already has a
1830 *     routable public IP address, then instead of complaining about it and giving an error,
1831 *     the PortMapping API just invokes your callback, giving the machine's public address
1832 *     and your own port number. This means you don't need to write code to work out whether
1833 *     your client needs to call the PortMapping API -- just call it anyway, and if it wasn't
1834 *     necessary, no harm is done:
1835 *
1836 *     - If the machine already has a routable public IP address, then your callback
1837 *       will just be invoked giving your own address and port.
1838 *     - If a NAT mapping is required and obtained, then your callback will be invoked
1839 *       giving you the external address and port.
1840 *     - If a NAT mapping is required but not obtained from the local NAT gateway,
1841 *       or the machine has no network connectivity, then your callback will be
1842 *       invoked giving zero address and port.
1843 *
1844 *  2. In other NAT mapping APIs, if a laptop computer is put to sleep and woken up on a new
1845 *     network, it's the client's job to notice this, and work out whether a NAT mapping
1846 *     is required on the new network, and make a new NAT mapping request if necessary.
1847 *     The DNSServiceNATPortMappingCreate API does this for you, automatically.
1848 *     The client just needs to make one call to the PortMapping API, and its callback will
1849 *     be invoked any time the mapping state changes. This property complements point (1) above.
1850 *     If the client didn't make a NAT mapping request just because it determined that one was
1851 *     not required at that particular moment in time, the client would then have to monitor
1852 *     for network state changes to determine if a NAT port mapping later became necessary.
1853 *     By unconditionally making a NAT mapping request, even when a NAT mapping not to be
1854 *     necessary, the PortMapping API will then begin monitoring network state changes on behalf of
1855 *     the client, and if a NAT mapping later becomes necessary, it will automatically create a NAT
1856 *     mapping and inform the client with a new callback giving the new address and port information.
1857 *
1858 * DNSServiceNATPortMappingReply() parameters:
1859 *
1860 * sdRef:           The DNSServiceRef initialized by DNSServiceNATPortMappingCreate().
1861 *
1862 * flags:           Currently unused, reserved for future use.
1863 *
1864 * interfaceIndex:  The interface through which the NAT gateway is reached.
1865 *
1866 * errorCode:       Will be kDNSServiceErr_NoError on success.
1867 *                  Will be kDNSServiceErr_DoubleNAT when the NAT gateway is itself behind one or
1868 *                  more layers of NAT, in which case the other parameters have the defined values.
1869 *                  For other failures, will indicate the failure that occurred, and the other
1870 *                  parameters are undefined.
1871 *
1872 * externalAddress: Four byte IPv4 address in network byte order.
1873 *
1874 * protocol:        Will be kDNSServiceProtocol_UDP or kDNSServiceProtocol_TCP or both.
1875 *
1876 * internalPort:    The port on the local machine that was mapped.
1877 *
1878 * externalPort:    The actual external port in the NAT gateway that was mapped.
1879 *                  This is likely to be different than the requested external port.
1880 *
1881 * ttl:             The lifetime of the NAT port mapping created on the gateway.
1882 *                  This controls how quickly stale mappings will be garbage-collected
1883 *                  if the client machine crashes, suffers a power failure, is disconnected
1884 *                  from the network, or suffers some other unfortunate demise which
1885 *                  causes it to vanish without explicitly removing its NAT port mapping.
1886 *                  It's possible that the ttl value will differ from the requested ttl value.
1887 *
1888 * context:         The context pointer that was passed to the callout.
1889 *
1890 */
1891
1892typedef void (DNSSD_API *DNSServiceNATPortMappingReply)
1893    (
1894    DNSServiceRef                    sdRef,
1895    DNSServiceFlags                  flags,
1896    uint32_t                         interfaceIndex,
1897    DNSServiceErrorType              errorCode,
1898    uint32_t                         externalAddress,   /* four byte IPv4 address in network byte order */
1899    DNSServiceProtocol               protocol,
1900    uint16_t                         internalPort,      /* In network byte order */
1901    uint16_t                         externalPort,      /* In network byte order and may be different than the requested port */
1902    uint32_t                         ttl,               /* may be different than the requested ttl */
1903    void                             *context
1904    );
1905
1906
1907/* DNSServiceNATPortMappingCreate() Parameters:
1908 *
1909 * sdRef:           A pointer to an uninitialized DNSServiceRef. If the call succeeds then it
1910 *                  initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the nat
1911 *                  port mapping will last indefinitely until the client terminates the port
1912 *                  mapping request by passing this DNSServiceRef to DNSServiceRefDeallocate().
1913 *
1914 * flags:           Currently ignored, reserved for future use.
1915 *
1916 * interfaceIndex:  The interface on which to create port mappings in a NAT gateway. Passing 0 causes
1917 *                  the port mapping request to be sent on the primary interface.
1918 *
1919 * protocol:        To request a port mapping, pass in kDNSServiceProtocol_UDP, or kDNSServiceProtocol_TCP,
1920 *                  or (kDNSServiceProtocol_UDP | kDNSServiceProtocol_TCP) to map both.
1921 *                  The local listening port number must also be specified in the internalPort parameter.
1922 *                  To just discover the NAT gateway's external IP address, pass zero for protocol,
1923 *                  internalPort, externalPort and ttl.
1924 *
1925 * internalPort:    The port number in network byte order on the local machine which is listening for packets.
1926 *
1927 * externalPort:    The requested external port in network byte order in the NAT gateway that you would
1928 *                  like to map to the internal port. Pass 0 if you don't care which external port is chosen for you.
1929 *
1930 * ttl:             The requested renewal period of the NAT port mapping, in seconds.
1931 *                  If the client machine crashes, suffers a power failure, is disconnected from
1932 *                  the network, or suffers some other unfortunate demise which causes it to vanish
1933 *                  unexpectedly without explicitly removing its NAT port mappings, then the NAT gateway
1934 *                  will garbage-collect old stale NAT port mappings when their lifetime expires.
1935 *                  Requesting a short TTL causes such orphaned mappings to be garbage-collected
1936 *                  more promptly, but consumes system resources and network bandwidth with
1937 *                  frequent renewal packets to keep the mapping from expiring.
1938 *                  Requesting a long TTL is more efficient on the network, but in the event of the
1939 *                  client vanishing, stale NAT port mappings will not be garbage-collected as quickly.
1940 *                  Most clients should pass 0 to use a system-wide default value.
1941 *
1942 * callBack:        The function to be called when the port mapping request succeeds or fails asynchronously.
1943 *
1944 * context:         An application context pointer which is passed to the callback function
1945 *                  (may be NULL).
1946 *
1947 * return value:    Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
1948 *                  errors are delivered to the callback), otherwise returns an error code indicating
1949 *                  the error that occurred.
1950 *
1951 *                  If you don't actually want a port mapped, and are just calling the API
1952 *                  because you want to find out the NAT's external IP address (e.g. for UI
1953 *                  display) then pass zero for protocol, internalPort, externalPort and ttl.
1954 */
1955
1956DNSServiceErrorType DNSSD_API DNSServiceNATPortMappingCreate
1957    (
1958    DNSServiceRef                    *sdRef,
1959    DNSServiceFlags                  flags,
1960    uint32_t                         interfaceIndex,
1961    DNSServiceProtocol               protocol,          /* TCP and/or UDP          */
1962    uint16_t                         internalPort,      /* network byte order      */
1963    uint16_t                         externalPort,      /* network byte order      */
1964    uint32_t                         ttl,               /* time to live in seconds */
1965    DNSServiceNATPortMappingReply    callBack,
1966    void                             *context           /* may be NULL             */
1967    );
1968
1969
1970typedef void (DNSSD_API *DNSHostnameChangedReply)
1971    (
1972    DNSServiceRef                    sdRef,
1973    DNSServiceFlags                  flags,
1974    DNSServiceErrorType              errorCode,
1975    const char                       *hostname,
1976    void                             *context
1977    );
1978
1979DNSServiceErrorType DNSSD_API DNSSetHostname
1980    (
1981    DNSServiceRef            *sdRef,
1982    DNSServiceFlags          flags,
1983    const char               *hostname,
1984    DNSHostnameChangedReply  callBack,
1985    void                     *context
1986    );
1987
1988/*********************************************************************************************
1989 *
1990 *  General Utility Functions
1991 *
1992 *********************************************************************************************/
1993
1994/* DNSServiceConstructFullName()
1995 *
1996 * Concatenate a three-part domain name (as returned by the above callbacks) into a
1997 * properly-escaped full domain name. Note that callbacks in the above functions ALREADY ESCAPE
1998 * strings where necessary.
1999 *
2000 * Parameters:
2001 *
2002 * fullName:        A pointer to a buffer that where the resulting full domain name is to be written.
2003 *                  The buffer must be kDNSServiceMaxDomainName (1009) bytes in length to
2004 *                  accommodate the longest legal domain name without buffer overrun.
2005 *
2006 * service:         The service name - any dots or backslashes must NOT be escaped.
2007 *                  May be NULL (to construct a PTR record name, e.g.
2008 *                  "_ftp._tcp.apple.com.").
2009 *
2010 * regtype:         The service type followed by the protocol, separated by a dot
2011 *                  (e.g. "_ftp._tcp").
2012 *
2013 * domain:          The domain name, e.g. "apple.com.". Literal dots or backslashes,
2014 *                  if any, must be escaped, e.g. "1st\. Floor.apple.com."
2015 *
2016 * return value:    Returns kDNSServiceErr_NoError (0) on success, kDNSServiceErr_BadParam on error.
2017 *
2018 */
2019
2020DNSServiceErrorType DNSSD_API DNSServiceConstructFullName
2021    (
2022    char                            * const fullName,
2023    const char                      * const service,      /* may be NULL */
2024    const char                      * const regtype,
2025    const char                      * const domain
2026    );
2027
2028
2029/*********************************************************************************************
2030 *
2031 *   TXT Record Construction Functions
2032 *
2033 *********************************************************************************************/
2034
2035/*
2036 * A typical calling sequence for TXT record construction is something like:
2037 *
2038 * Client allocates storage for TXTRecord data (e.g. declare buffer on the stack)
2039 * TXTRecordCreate();
2040 * TXTRecordSetValue();
2041 * TXTRecordSetValue();
2042 * TXTRecordSetValue();
2043 * ...
2044 * DNSServiceRegister( ... TXTRecordGetLength(), TXTRecordGetBytesPtr() ... );
2045 * TXTRecordDeallocate();
2046 * Explicitly deallocate storage for TXTRecord data (if not allocated on the stack)
2047 */
2048
2049
2050/* TXTRecordRef
2051 *
2052 * Opaque internal data type.
2053 * Note: Represents a DNS-SD TXT record.
2054 */
2055
2056typedef union _TXTRecordRef_t { char PrivateData[16]; char *ForceNaturalAlignment; } TXTRecordRef;
2057
2058
2059/* TXTRecordCreate()
2060 *
2061 * Creates a new empty TXTRecordRef referencing the specified storage.
2062 *
2063 * If the buffer parameter is NULL, or the specified storage size is not
2064 * large enough to hold a key subsequently added using TXTRecordSetValue(),
2065 * then additional memory will be added as needed using malloc().
2066 *
2067 * On some platforms, when memory is low, malloc() may fail. In this
2068 * case, TXTRecordSetValue() will return kDNSServiceErr_NoMemory, and this
2069 * error condition will need to be handled as appropriate by the caller.
2070 *
2071 * You can avoid the need to handle this error condition if you ensure
2072 * that the storage you initially provide is large enough to hold all
2073 * the key/value pairs that are to be added to the record.
2074 * The caller can precompute the exact length required for all of the
2075 * key/value pairs to be added, or simply provide a fixed-sized buffer
2076 * known in advance to be large enough.
2077 * A no-value (key-only) key requires  (1 + key length) bytes.
2078 * A key with empty value requires     (1 + key length + 1) bytes.
2079 * A key with non-empty value requires (1 + key length + 1 + value length).
2080 * For most applications, DNS-SD TXT records are generally
2081 * less than 100 bytes, so in most cases a simple fixed-sized
2082 * 256-byte buffer will be more than sufficient.
2083 * Recommended size limits for DNS-SD TXT Records are discussed in
2084 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt>
2085 *
2086 * Note: When passing parameters to and from these TXT record APIs,
2087 * the key name does not include the '=' character. The '=' character
2088 * is the separator between the key and value in the on-the-wire
2089 * packet format; it is not part of either the key or the value.
2090 *
2091 * txtRecord:       A pointer to an uninitialized TXTRecordRef.
2092 *
2093 * bufferLen:       The size of the storage provided in the "buffer" parameter.
2094 *
2095 * buffer:          Optional caller-supplied storage used to hold the TXTRecord data.
2096 *                  This storage must remain valid for as long as
2097 *                  the TXTRecordRef.
2098 */
2099
2100void DNSSD_API TXTRecordCreate
2101    (
2102    TXTRecordRef     *txtRecord,
2103    uint16_t         bufferLen,
2104    void             *buffer
2105    );
2106
2107
2108/* TXTRecordDeallocate()
2109 *
2110 * Releases any resources allocated in the course of preparing a TXT Record
2111 * using TXTRecordCreate()/TXTRecordSetValue()/TXTRecordRemoveValue().
2112 * Ownership of the buffer provided in TXTRecordCreate() returns to the client.
2113 *
2114 * txtRecord:           A TXTRecordRef initialized by calling TXTRecordCreate().
2115 *
2116 */
2117
2118void DNSSD_API TXTRecordDeallocate
2119    (
2120    TXTRecordRef     *txtRecord
2121    );
2122
2123
2124/* TXTRecordSetValue()
2125 *
2126 * Adds a key (optionally with value) to a TXTRecordRef. If the "key" already
2127 * exists in the TXTRecordRef, then the current value will be replaced with
2128 * the new value.
2129 * Keys may exist in four states with respect to a given TXT record:
2130 *  - Absent (key does not appear at all)
2131 *  - Present with no value ("key" appears alone)
2132 *  - Present with empty value ("key=" appears in TXT record)
2133 *  - Present with non-empty value ("key=value" appears in TXT record)
2134 * For more details refer to "Data Syntax for DNS-SD TXT Records" in
2135 * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt>
2136 *
2137 * txtRecord:       A TXTRecordRef initialized by calling TXTRecordCreate().
2138 *
2139 * key:             A null-terminated string which only contains printable ASCII
2140 *                  values (0x20-0x7E), excluding '=' (0x3D). Keys should be
2141 *                  9 characters or fewer (not counting the terminating null).
2142 *
2143 * valueSize:       The size of the value.
2144 *
2145 * value:           Any binary value. For values that represent
2146 *                  textual data, UTF-8 is STRONGLY recommended.
2147 *                  For values that represent textual data, valueSize
2148 *                  should NOT include the terminating null (if any)
2149 *                  at the end of the string.
2150 *                  If NULL, then "key" will be added with no value.
2151 *                  If non-NULL but valueSize is zero, then "key=" will be
2152 *                  added with empty value.
2153 *
2154 * return value:    Returns kDNSServiceErr_NoError on success.
2155 *                  Returns kDNSServiceErr_Invalid if the "key" string contains
2156 *                  illegal characters.
2157 *                  Returns kDNSServiceErr_NoMemory if adding this key would
2158 *                  exceed the available storage.
2159 */
2160
2161DNSServiceErrorType DNSSD_API TXTRecordSetValue
2162    (
2163    TXTRecordRef     *txtRecord,
2164    const char       *key,
2165    uint8_t          valueSize,        /* may be zero */
2166    const void       *value            /* may be NULL */
2167    );
2168
2169
2170/* TXTRecordRemoveValue()
2171 *
2172 * Removes a key from a TXTRecordRef. The "key" must be an
2173 * ASCII string which exists in the TXTRecordRef.
2174 *
2175 * txtRecord:       A TXTRecordRef initialized by calling TXTRecordCreate().
2176 *
2177 * key:             A key name which exists in the TXTRecordRef.
2178 *
2179 * return value:    Returns kDNSServiceErr_NoError on success.
2180 *                  Returns kDNSServiceErr_NoSuchKey if the "key" does not
2181 *                  exist in the TXTRecordRef.
2182 */
2183
2184DNSServiceErrorType DNSSD_API TXTRecordRemoveValue
2185    (
2186    TXTRecordRef     *txtRecord,
2187    const char       *key
2188    );
2189
2190
2191/* TXTRecordGetLength()
2192 *
2193 * Allows you to determine the length of the raw bytes within a TXTRecordRef.
2194 *
2195 * txtRecord:       A TXTRecordRef initialized by calling TXTRecordCreate().
2196 *
2197 * return value:    Returns the size of the raw bytes inside a TXTRecordRef
2198 *                  which you can pass directly to DNSServiceRegister() or
2199 *                  to DNSServiceUpdateRecord().
2200 *                  Returns 0 if the TXTRecordRef is empty.
2201 */
2202
2203uint16_t DNSSD_API TXTRecordGetLength
2204    (
2205    const TXTRecordRef *txtRecord
2206    );
2207
2208
2209/* TXTRecordGetBytesPtr()
2210 *
2211 * Allows you to retrieve a pointer to the raw bytes within a TXTRecordRef.
2212 *
2213 * txtRecord:       A TXTRecordRef initialized by calling TXTRecordCreate().
2214 *
2215 * return value:    Returns a pointer to the raw bytes inside the TXTRecordRef
2216 *                  which you can pass directly to DNSServiceRegister() or
2217 *                  to DNSServiceUpdateRecord().
2218 */
2219
2220const void * DNSSD_API TXTRecordGetBytesPtr
2221    (
2222    const TXTRecordRef *txtRecord
2223    );
2224
2225
2226/*********************************************************************************************
2227 *
2228 *   TXT Record Parsing Functions
2229 *
2230 *********************************************************************************************/
2231
2232/*
2233 * A typical calling sequence for TXT record parsing is something like:
2234 *
2235 * Receive TXT record data in DNSServiceResolve() callback
2236 * if (TXTRecordContainsKey(txtLen, txtRecord, "key")) then do something
2237 * val1ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key1", &len1);
2238 * val2ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key2", &len2);
2239 * ...
2240 * memcpy(myval1, val1ptr, len1);
2241 * memcpy(myval2, val2ptr, len2);
2242 * ...
2243 * return;
2244 *
2245 * If you wish to retain the values after return from the DNSServiceResolve()
2246 * callback, then you need to copy the data to your own storage using memcpy()
2247 * or similar, as shown in the example above.
2248 *
2249 * If for some reason you need to parse a TXT record you built yourself
2250 * using the TXT record construction functions above, then you can do
2251 * that using TXTRecordGetLength and TXTRecordGetBytesPtr calls:
2252 * TXTRecordGetValue(TXTRecordGetLength(x), TXTRecordGetBytesPtr(x), key, &len);
2253 *
2254 * Most applications only fetch keys they know about from a TXT record and
2255 * ignore the rest.
2256 * However, some debugging tools wish to fetch and display all keys.
2257 * To do that, use the TXTRecordGetCount() and TXTRecordGetItemAtIndex() calls.
2258 */
2259
2260/* TXTRecordContainsKey()
2261 *
2262 * Allows you to determine if a given TXT Record contains a specified key.
2263 *
2264 * txtLen:          The size of the received TXT Record.
2265 *
2266 * txtRecord:       Pointer to the received TXT Record bytes.
2267 *
2268 * key:             A null-terminated ASCII string containing the key name.
2269 *
2270 * return value:    Returns 1 if the TXT Record contains the specified key.
2271 *                  Otherwise, it returns 0.
2272 */
2273
2274int DNSSD_API TXTRecordContainsKey
2275    (
2276    uint16_t         txtLen,
2277    const void       *txtRecord,
2278    const char       *key
2279    );
2280
2281
2282/* TXTRecordGetValuePtr()
2283 *
2284 * Allows you to retrieve the value for a given key from a TXT Record.
2285 *
2286 * txtLen:          The size of the received TXT Record
2287 *
2288 * txtRecord:       Pointer to the received TXT Record bytes.
2289 *
2290 * key:             A null-terminated ASCII string containing the key name.
2291 *
2292 * valueLen:        On output, will be set to the size of the "value" data.
2293 *
2294 * return value:    Returns NULL if the key does not exist in this TXT record,
2295 *                  or exists with no value (to differentiate between
2296 *                  these two cases use TXTRecordContainsKey()).
2297 *                  Returns pointer to location within TXT Record bytes
2298 *                  if the key exists with empty or non-empty value.
2299 *                  For empty value, valueLen will be zero.
2300 *                  For non-empty value, valueLen will be length of value data.
2301 */
2302
2303const void * DNSSD_API TXTRecordGetValuePtr
2304    (
2305    uint16_t         txtLen,
2306    const void       *txtRecord,
2307    const char       *key,
2308    uint8_t          *valueLen
2309    );
2310
2311
2312/* TXTRecordGetCount()
2313 *
2314 * Returns the number of keys stored in the TXT Record. The count
2315 * can be used with TXTRecordGetItemAtIndex() to iterate through the keys.
2316 *
2317 * txtLen:          The size of the received TXT Record.
2318 *
2319 * txtRecord:       Pointer to the received TXT Record bytes.
2320 *
2321 * return value:    Returns the total number of keys in the TXT Record.
2322 *
2323 */
2324
2325uint16_t DNSSD_API TXTRecordGetCount
2326    (
2327    uint16_t         txtLen,
2328    const void       *txtRecord
2329    );
2330
2331
2332/* TXTRecordGetItemAtIndex()
2333 *
2334 * Allows you to retrieve a key name and value pointer, given an index into
2335 * a TXT Record. Legal index values range from zero to TXTRecordGetCount()-1.
2336 * It's also possible to iterate through keys in a TXT record by simply
2337 * calling TXTRecordGetItemAtIndex() repeatedly, beginning with index zero
2338 * and increasing until TXTRecordGetItemAtIndex() returns kDNSServiceErr_Invalid.
2339 *
2340 * On return:
2341 * For keys with no value, *value is set to NULL and *valueLen is zero.
2342 * For keys with empty value, *value is non-NULL and *valueLen is zero.
2343 * For keys with non-empty value, *value is non-NULL and *valueLen is non-zero.
2344 *
2345 * txtLen:          The size of the received TXT Record.
2346 *
2347 * txtRecord:       Pointer to the received TXT Record bytes.
2348 *
2349 * itemIndex:       An index into the TXT Record.
2350 *
2351 * keyBufLen:       The size of the string buffer being supplied.
2352 *
2353 * key:             A string buffer used to store the key name.
2354 *                  On return, the buffer contains a null-terminated C string
2355 *                  giving the key name. DNS-SD TXT keys are usually
2356 *                  9 characters or fewer. To hold the maximum possible
2357 *                  key name, the buffer should be 256 bytes long.
2358 *
2359 * valueLen:        On output, will be set to the size of the "value" data.
2360 *
2361 * value:           On output, *value is set to point to location within TXT
2362 *                  Record bytes that holds the value data.
2363 *
2364 * return value:    Returns kDNSServiceErr_NoError on success.
2365 *                  Returns kDNSServiceErr_NoMemory if keyBufLen is too short.
2366 *                  Returns kDNSServiceErr_Invalid if index is greater than
2367 *                  TXTRecordGetCount()-1.
2368 */
2369
2370DNSServiceErrorType DNSSD_API TXTRecordGetItemAtIndex
2371    (
2372    uint16_t         txtLen,
2373    const void       *txtRecord,
2374    uint16_t         itemIndex,
2375    uint16_t         keyBufLen,
2376    char             *key,
2377    uint8_t          *valueLen,
2378    const void       **value
2379    );
2380
2381#if _DNS_SD_LIBDISPATCH
2382/*
2383* DNSServiceSetDispatchQueue
2384*
2385* Allows you to schedule a DNSServiceRef on a serial dispatch queue for receiving asynchronous
2386* callbacks.  It's the clients responsibility to ensure that the provided dispatch queue is running.
2387*
2388* A typical application that uses CFRunLoopRun or dispatch_main on its main thread will
2389* usually schedule DNSServiceRefs on its main queue (which is always a serial queue)
2390* using "DNSServiceSetDispatchQueue(sdref, dispatch_get_main_queue());"
2391*
2392* If there is any error during the processing of events, the application callback will
2393* be called with an error code. For shared connections, each subordinate DNSServiceRef
2394* will get its own error callback. Currently these error callbacks only happen
2395* if the mDNSResponder daemon is manually terminated or crashes, and the error
2396* code in this case is kDNSServiceErr_ServiceNotRunning. The application must call
2397* DNSServiceRefDeallocate to free the DNSServiceRef when it gets such an error code.
2398* These error callbacks are rare and should not normally happen on customer machines,
2399* but application code should be written defensively to handle such error callbacks
2400* gracefully if they occur.
2401*
2402* After using DNSServiceSetDispatchQueue on a DNSServiceRef, calling DNSServiceProcessResult
2403* on the same DNSServiceRef will result in undefined behavior and should be avoided.
2404*
2405* Once the application successfully schedules a DNSServiceRef on a serial dispatch queue using
2406* DNSServiceSetDispatchQueue, it cannot remove the DNSServiceRef from the dispatch queue, or use
2407* DNSServiceSetDispatchQueue a second time to schedule the DNSServiceRef onto a different serial dispatch
2408* queue. Once scheduled onto a dispatch queue a DNSServiceRef will deliver events to that queue until
2409* the application no longer requires that operation and terminates it using DNSServiceRefDeallocate.
2410*
2411* service:         DNSServiceRef that was allocated and returned to the application, when the
2412*                  application calls one of the DNSService API.
2413*
2414* queue:           dispatch queue where the application callback will be scheduled
2415*
2416* return value:    Returns kDNSServiceErr_NoError on success.
2417*                  Returns kDNSServiceErr_NoMemory if it cannot create a dispatch source
2418*                  Returns kDNSServiceErr_BadParam if the service param is invalid or the
2419*                  queue param is invalid
2420*/
2421
2422DNSServiceErrorType DNSSD_API DNSServiceSetDispatchQueue
2423  (
2424  DNSServiceRef service,
2425  dispatch_queue_t queue
2426  );
2427#endif //_DNS_SD_LIBDISPATCH
2428
2429#ifdef __APPLE_API_PRIVATE
2430
2431#define kDNSServiceCompPrivateDNS   "PrivateDNS"
2432#define kDNSServiceCompMulticastDNS "MulticastDNS"
2433
2434#endif //__APPLE_API_PRIVATE
2435
2436/* Some C compiler cleverness. We can make the compiler check certain things for us,
2437 * and report errors at compile-time if anything is wrong. The usual way to do this would
2438 * be to use a run-time "if" statement or the conventional run-time "assert" mechanism, but
2439 * then you don't find out what's wrong until you run the software. This way, if the assertion
2440 * condition is false, the array size is negative, and the complier complains immediately.
2441 */
2442
2443struct CompileTimeAssertionChecks_DNS_SD
2444    {
2445    char assert0[(sizeof(union _TXTRecordRef_t) == 16) ? 1 : -1];
2446    };
2447
2448#ifdef  __cplusplus
2449    }
2450#endif
2451
2452#endif  /* _DNS_SD_H */
2453