1/* -*- Mode: C; tab-width: 4 -*-
2 *
3 * Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#ifndef __UDNS_H_
19#define __UDNS_H_
20
21#include "mDNSEmbeddedAPI.h"
22#include "DNSCommon.h"
23
24#ifdef	__cplusplus
25	extern "C" {
26#endif
27
28#define RESTART_GOODBYE_DELAY    (6 * mDNSPlatformOneSecond) // delay after restarting LLQ before nuking previous known answers (avoids flutter if we restart before we have networking up)
29#define INIT_UCAST_POLL_INTERVAL (3 * mDNSPlatformOneSecond) // this interval is used after send failures on network transitions
30	                                                         // which typically heal quickly, so we start agressively and exponentially back off
31#define MAX_UCAST_POLL_INTERVAL (60 * 60 * mDNSPlatformOneSecond)
32//#define MAX_UCAST_POLL_INTERVAL (1 * 60 * mDNSPlatformOneSecond)
33#define LLQ_POLL_INTERVAL       (15 * 60 * mDNSPlatformOneSecond) // Polling interval for zones w/ an advertised LLQ port (ie not static zones) if LLQ fails due to NAT, etc.
34#define RESPONSE_WINDOW (60 * mDNSPlatformOneSecond)         // require server responses within one minute of request
35#define MAX_UCAST_UNANSWERED_QUERIES 2                       // the number of unanswered queries from any one uDNS server before trying another server
36#define DNSSERVER_PENALTY_TIME (60 * mDNSPlatformOneSecond) // number of seconds for which new questions don't pick this server
37
38#define DEFAULT_UPDATE_LEASE 7200
39
40#define QuestionIntervalStep 3
41#define QuestionIntervalStep2 (QuestionIntervalStep*QuestionIntervalStep)
42#define QuestionIntervalStep3 (QuestionIntervalStep*QuestionIntervalStep*QuestionIntervalStep)
43#define InitialQuestionInterval ((mDNSPlatformOneSecond + QuestionIntervalStep-1) / QuestionIntervalStep)
44
45// For Unicast record registrations, we initialize the interval to 1 second. When we send any query for
46// the record registration e.g., GetZoneData, we always back off by QuestionIntervalStep
47// so that the first retry does not happen until 3 seconds which should be enough for TCP/TLS to be done.
48#define INIT_RECORD_REG_INTERVAL (1 * mDNSPlatformOneSecond)
49#define MAX_RECORD_REG_INTERVAL	(15 * 60 * mDNSPlatformOneSecond)
50#define MERGE_DELAY_TIME	(1 * mDNSPlatformOneSecond)
51
52// If we are refreshing, we do it at least 5 times with a min update frequency of
53// 5 minutes
54#define MAX_UPDATE_REFRESH_COUNT	5
55#define MIN_UPDATE_REFRESH_TIME		(5 * 60 * mDNSPlatformOneSecond)
56
57// For questions that use kDNSServiceFlagsTimeout and we don't have a matching resolver e.g., no dns servers,
58// then use the default value of 30 seconds
59#define DEFAULT_UDNS_TIMEOUT	30 // in seconds
60
61// Entry points into unicast-specific routines
62
63extern void LLQGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneInfo);
64extern void startLLQHandshake(mDNS *m, DNSQuestion *q);
65extern void sendLLQRefresh(mDNS *m, DNSQuestion *q);
66
67extern void SleepRecordRegistrations(mDNS *m);
68
69// uDNS_UpdateRecord
70// following fields must be set, and the update validated, upon entry.
71// rr->NewRData
72// rr->newrdlength
73// rr->UpdateCallback
74
75extern mStatus uDNS_UpdateRecord(mDNS *m, AuthRecord *rr);
76
77extern void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q);
78extern CacheGroup *CacheGroupForName(const mDNS *const m, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name);
79extern mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr);
80extern mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt);
81extern mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question);
82extern mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question);
83extern mStatus mDNS_StartNATOperation_internal(mDNS *const m, NATTraversalInfo *traversal);
84
85extern void RecordRegistrationGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneData);
86extern mStatus uDNS_DeregisterRecord(mDNS *const m, AuthRecord *const rr);
87extern const domainname *GetServiceTarget(mDNS *m, AuthRecord *const rr);
88extern void uDNS_CheckCurrentQuestion(mDNS *const m);
89
90// integer fields of msg header must be in HOST byte order before calling this routine
91extern void uDNS_ReceiveMsg(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end,
92	const mDNSAddr *const srcaddr, const mDNSIPPort srcport);
93
94extern void uDNS_Tasks(mDNS *const m);
95extern void UpdateAllSRVRecords(mDNS *m);
96extern void CheckNATMappings(mDNS *m);
97
98extern mStatus         uDNS_SetupDNSConfig(mDNS *const m);
99
100// uDNS_SetupSearchDomains by default adds search domains. It also can be called with one or
101// more values for "action" which does the following:
102//
103// -UDNS_START_WAB_QUERY - start Wide Area Bonjour (domain enumeration) queries
104
105#define UDNS_START_WAB_QUERY    0x00000001
106
107extern mStatus         uDNS_SetupSearchDomains(mDNS *const m, int action);
108extern domainname      *uDNS_GetNextSearchDomain(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSs8 *searchIndex, mDNSBool ignoreDotLocal);
109
110typedef enum
111	{
112	uDNS_LLQ_Not = 0,	// Normal uDNS answer: Flush any stale records from cache, and respect record TTL
113	uDNS_LLQ_Ignore,	// LLQ initial challenge packet: ignore -- has no useful records for us
114	uDNS_LLQ_Entire,	// LLQ initial set of answers: Flush any stale records from cache, but assume TTL is 2 x LLQ refresh interval
115	uDNS_LLQ_Events		// LLQ event packet: don't flush cache; assume TTL is 2 x LLQ refresh interval
116	} uDNS_LLQType;
117
118extern uDNS_LLQType    uDNS_recvLLQResponse(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end, const mDNSAddr *const srcaddr, const mDNSIPPort srcport, DNSQuestion **matchQuestion);
119extern DomainAuthInfo *GetAuthInfoForName_internal(mDNS *m, const domainname *const name);
120extern DomainAuthInfo *GetAuthInfoForQuestion(mDNS *m, const DNSQuestion *const q);
121extern void DisposeTCPConn(struct tcpInfo_t *tcp);
122
123// NAT traversal
124extern void	uDNS_ReceiveNATPMPPacket(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *pkt, mDNSu16 len);	// Called for each received NAT-PMP packet
125extern void	natTraversalHandleAddressReply(mDNS *const m, mDNSu16 err, mDNSv4Addr ExtAddr);
126extern void	natTraversalHandlePortMapReply(mDNS *const m, NATTraversalInfo *n, const mDNSInterfaceID InterfaceID, mDNSu16 err, mDNSIPPort extport, mDNSu32 lease);
127
128#ifdef	__cplusplus
129	}
130#endif
131
132#endif // __UDNS_H_
133