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 63 extern void LLQGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneInfo); 64 extern void startLLQHandshake(mDNS *m, DNSQuestion *q); 65 extern void sendLLQRefresh(mDNS *m, DNSQuestion *q); 66 67 extern 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 75 extern mStatus uDNS_UpdateRecord(mDNS *m, AuthRecord *rr); 76 77 extern void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q); 78 extern CacheGroup *CacheGroupForName(const mDNS *const m, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name); 79 extern mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr); 80 extern mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt); 81 extern mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question); 82 extern mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question); 83 extern mStatus mDNS_StartNATOperation_internal(mDNS *const m, NATTraversalInfo *traversal); 84 85 extern void RecordRegistrationGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneData); 86 extern mStatus uDNS_DeregisterRecord(mDNS *const m, AuthRecord *const rr); 87 extern const domainname *GetServiceTarget(mDNS *m, AuthRecord *const rr); 88 extern void uDNS_CheckCurrentQuestion(mDNS *const m); 89 90 // integer fields of msg header must be in HOST byte order before calling this routine 91 extern void uDNS_ReceiveMsg(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end, 92 const mDNSAddr *const srcaddr, const mDNSIPPort srcport); 93 94 extern void uDNS_Tasks(mDNS *const m); 95 extern void UpdateAllSRVRecords(mDNS *m); 96 extern void CheckNATMappings(mDNS *m); 97 98 extern 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 106 107 extern mStatus uDNS_SetupSearchDomains(mDNS *const m, int action); 108 extern domainname *uDNS_GetNextSearchDomain(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSs8 *searchIndex, mDNSBool ignoreDotLocal); 109 110 typedef 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; 117 118 extern uDNS_LLQType uDNS_recvLLQResponse(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end, const mDNSAddr *const srcaddr, const mDNSIPPort srcport, DNSQuestion **matchQuestion); 119 extern DomainAuthInfo *GetAuthInfoForName_internal(mDNS *m, const domainname *const name); 120 extern DomainAuthInfo *GetAuthInfoForQuestion(mDNS *m, const DNSQuestion *const q); 121 extern void DisposeTCPConn(struct tcpInfo_t *tcp); 122 123 // NAT traversal 124 extern void uDNS_ReceiveNATPMPPacket(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *pkt, mDNSu16 len); // Called for each received NAT-PMP packet 125 extern void natTraversalHandleAddressReply(mDNS *const m, mDNSu16 err, mDNSv4Addr ExtAddr); 126 extern 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