mDNSCore/uDNS.h

   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 // Entry points into unicast-specific routines
  57
  58 extern void LLQGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneInfo);
  59 extern void startLLQHandshake(mDNS *m, DNSQuestion *q);
  60 extern void sendLLQRefresh(mDNS *m, DNSQuestion *q);
  61
  62 extern void SleepRecordRegistrations(mDNS *m);
  63
  64 // uDNS_UpdateRecord
  65 // following fields must be set, and the update validated, upon entry.
  66 // rr->NewRData
  67 // rr->newrdlength
  68 // rr->UpdateCallback
  69
  70 extern mStatus uDNS_UpdateRecord(mDNS *m, AuthRecord *rr);
  71
  72 extern void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q);
  73 extern CacheGroup *CacheGroupForName(const mDNS *const m, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name);
  74 extern mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr);
  75 extern mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt);
  76 extern mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question);
  77 extern mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question);
  78 extern mStatus mDNS_StartNATOperation_internal(mDNS *const m, NATTraversalInfo *traversal);
  79
  80 extern void RecordRegistrationGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneData);
  81 extern mStatus uDNS_DeregisterRecord(mDNS *const m, AuthRecord *const rr);
  82 extern const domainname *GetServiceTarget(mDNS *m, AuthRecord *const rr);
  83 extern void uDNS_CheckCurrentQuestion(mDNS *const m);
  84
  85 // integer fields of msg header must be in HOST byte order before calling this routine
  86 extern void uDNS_ReceiveMsg(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end,
  87         const mDNSAddr *const srcaddr, const mDNSIPPort srcport);
  88
  89 extern void uDNS_Tasks(mDNS *const m);
  90 extern void UpdateAllSRVRecords(mDNS *m);
  91 extern void CheckNATMappings(mDNS *m);
  92
  93 extern mStatus         uDNS_SetupDNSConfig(mDNS *const m);
  94
  95 // uDNS_SetupSearchDomains by default adds search domains. It also can be called with one or
  96 // more values for "action" which does the following:
  97 //
  98 // -UDNS_START_WAB_QUERY - start Wide Area Bonjour (domain enumeration) queries
  99 // -UDNS_START_CF_QUERY - start Configuration query
 100
 101 #define UDNS_START_WAB_QUERY    0x00000001
 102 #define UDNS_START_CF_QUERY     0x00000002
 103
 104 extern mStatus         uDNS_SetupSearchDomains(mDNS *const m, int action);
 105
 106 typedef enum
 107         {
 108         uDNS_LLQ_Not = 0,       // Normal uDNS answer: Flush any stale records from cache, and respect record TTL
 109         uDNS_LLQ_Ignore,        // LLQ initial challenge packet: ignore -- has no useful records for us
 110         uDNS_LLQ_Entire,        // LLQ initial set of answers: Flush any stale records from cache, but assume TTL is 2 x LLQ refresh interval
 111         uDNS_LLQ_Events         // LLQ event packet: don't flush cache; assume TTL is 2 x LLQ refresh interval
 112         } uDNS_LLQType;
 113
 114 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);
 115 extern DomainAuthInfo *GetAuthInfoForName_internal(mDNS *m, const domainname *const name);
 116 extern DomainAuthInfo *GetAuthInfoForQuestion(mDNS *m, const DNSQuestion *const q);
 117 extern void DisposeTCPConn(struct tcpInfo_t *tcp);
 118
 119 // NAT traversal
 120 extern void     uDNS_ReceiveNATPMPPacket(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *pkt, mDNSu16 len); // Called for each received NAT-PMP packet
 121 extern void     natTraversalHandleAddressReply(mDNS *const m, mDNSu16 err, mDNSv4Addr ExtAddr);
 122 extern void     natTraversalHandlePortMapReply(mDNS *const m, NATTraversalInfo *n, const mDNSInterfaceID InterfaceID, mDNSu16 err, mDNSIPPort extport, mDNSu32 lease);
 123
 124 #ifdef  __cplusplus
 125         }
 126 #endif
 127
 128 #endif // __UDNS_H_