/* * Copyright (c) 2002-2021 Apple Inc. All rights reserved. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef __UDNS_H_ #define __UDNS_H_ #include "nullability.h" #include "mDNSEmbeddedAPI.h" #include "DNSCommon.h" #include #if MDNSRESPONDER_SUPPORTS(COMMON, DNS_PUSH) #include "dso.h" #include "dso-transport.h" #endif #ifdef __cplusplus extern "C" { #endif #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) #define INIT_UCAST_POLL_INTERVAL (3 * mDNSPlatformOneSecond) // this interval is used after send failures on network transitions // which typically heal quickly, so we start agressively and exponentially back off #define MAX_UCAST_POLL_INTERVAL (60 * 60 * mDNSPlatformOneSecond) //#define MAX_UCAST_POLL_INTERVAL (1 * 60 * mDNSPlatformOneSecond) #define LLQ_POLL_INTERVAL_MIN 15 #define LLQ_POLL_INTERVAL (LLQ_POLL_INTERVAL_MIN * 60 * mDNSPlatformOneSecond) // Polling interval for zones w/ an advertised LLQ port (ie not static zones) if LLQ fails due to NAT, etc. #define RESPONSE_WINDOW (60 * mDNSPlatformOneSecond) // require server responses within one minute of request #define MAX_UCAST_UNANSWERED_QUERIES 2 // number of unanswered queries from any one uDNS server before trying another server #define DNSSERVER_PENALTY_TIME (60 * mDNSPlatformOneSecond) // number of seconds for which new questions don't pick this server // On some interfaces, we want to delay the first retransmission to a minimum of 2 seconds // rather than the default (1 second). #define MIN_UCAST_RETRANS_TIMEOUT (2 * mDNSPlatformOneSecond) #define DEFAULT_UPDATE_LEASE 7200 #define QuestionIntervalStep 3 #define QuestionIntervalStep2 (QuestionIntervalStep*QuestionIntervalStep) #define QuestionIntervalStep3 (QuestionIntervalStep*QuestionIntervalStep*QuestionIntervalStep) #define InitialQuestionInterval ((mDNSPlatformOneSecond + QuestionIntervalStep-1) / QuestionIntervalStep) #define MaxQuestionInterval (3600 * mDNSPlatformOneSecond) #define UDNSBackOffMultiplier 2 #define MinQuestionInterval (1 * mDNSPlatformOneSecond) // For Unicast record registrations, we initialize the interval to 1 second. When we send any query for // the record registration e.g., GetZoneData, we always back off by QuestionIntervalStep // so that the first retry does not happen until 3 seconds which should be enough for TCP/TLS to be done. #define INIT_RECORD_REG_INTERVAL (1 * mDNSPlatformOneSecond) #define MAX_RECORD_REG_INTERVAL (15 * 60 * mDNSPlatformOneSecond) #define MERGE_DELAY_TIME (1 * mDNSPlatformOneSecond) // If we are refreshing, we do it at least 5 times with a min update frequency of // 5 minutes #define MAX_UPDATE_REFRESH_COUNT 5 #define MIN_UPDATE_REFRESH_TIME (5 * 60 * mDNSPlatformOneSecond) // For questions that use kDNSServiceFlagsTimeout and we don't have a matching resolver e.g., no dns servers, // then use the default value of 30 seconds #define DEFAULT_UDNS_TIMEOUT 30 // in seconds #if MDNSRESPONDER_SUPPORTS(COMMON, DNS_PUSH) // Reference count helper for DNSPushServer and DNSPushZone. #define DNS_PUSH_RETAIN(OBJ) \ do \ { \ (OBJ)->refCount++; \ LogRedact(MDNS_LOG_CATEGORY_DEFAULT, MDNS_LOG_DEBUG, \ "DNS push object retained - object: %p, refCount after retaining: %u.", (OBJ), (OBJ)->refCount); \ } while (mDNSfalse) #define DNS_PUSH_RELEASE(OBJ, FINALIZER) \ do \ { \ (OBJ)->refCount--; \ LogRedact(MDNS_LOG_CATEGORY_DEFAULT, MDNS_LOG_DEBUG, \ "DNS push object released - object: %p, refCount after releasing: %u.", (OBJ), (OBJ)->refCount); \ if ((OBJ)->refCount == 0) \ { \ FINALIZER((OBJ)); \ (OBJ) = NULL; \ } \ } while (mDNSfalse) // Push notification structures. struct mDNS_DNSPushServer { uint32_t serial; // The serial number that can be used to identify a specific server. uint32_t refCount; // Reference count used by DNS_PUSH_RETAIN and DNS_PUSH_RELEASE. dso_connect_state_t *connectInfo; // DSO Connection state information. dso_state_t *connection; // DNS Stateful Operations/TCP Connection pointer, might be null. DNSPushServer_ConnectState connectState; // Current status of connection attempt to this server. mDNSs32 lastDisconnect; // Last time we got a disconnect, used to avoid constant reconnects. domainname serverName; // The hostname returned by the _dns-push-tls._tcp. SRV lookup. mDNSIPPort port; // The port from the SRV lookup. #if MDNSRESPONDER_SUPPORTS(APPLE, QUERIER) mdns_dns_service_t dnsservice; #else DNSServer *qDNSServer; // DNS server stolen from the question that created this server structure. #endif mDNS *m; mDNSBool canceling; // Indicates if the current server is being canceled. DNSPushServer *next; } ; struct mDNS_DNSPushZone { uint32_t refCount; // Reference count used by DNS_PUSH_RETAIN and DNS_PUSH_RELEASE. domainname zoneName; DNSPushServer *server; // DNS Push Servers for this zone. DNSPushZone *next; } ; #endif // Entry points into unicast-specific routines extern void LLQGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneInfo); extern void startLLQHandshake(mDNS *m, DNSQuestion *q); extern void sendLLQRefresh(mDNS *m, DNSQuestion *q); #if MDNSRESPONDER_SUPPORTS(COMMON, DNS_PUSH) extern void DNSPushGotZoneData(mDNS *m, mStatus err, const ZoneData *zoneInfo); extern void DiscoverDNSPushServer(mDNS *m, DNSQuestion *q); extern void UnsubscribeQuestionFromDNSPushServer(mDNS *m, DNSQuestion *q, mDNSBool fallBackToLLQPoll); extern void UnsubscribeAllQuestionsFromDNSPushServer(mDNS *m, DNSPushServer *server); extern void DNSPushZoneRemove(mDNS *m, const DNSPushServer *server); extern void DNSPushZoneFinalize(DNSPushZone *zone); extern mDNSInterfaceID DNSPushServerGetInterfaceID(mDNS *m, const DNSPushServer *server); extern void DNSPushServerCancel(DNSPushServer *server, mDNSBool alreadyRemovedFromSystem); extern void DNSPushServerFinalize(DNSPushServer *server); extern void DNSPushUpdateQuestionDuplicate(DNSQuestion *primary, DNSQuestion *duplicate); #endif extern void GetZoneData_QuestionCallback(mDNS *m, DNSQuestion *question, const ResourceRecord *answer, QC_result AddRecord); extern void SleepRecordRegistrations(mDNS *m); // uDNS_UpdateRecord // following fields must be set, and the update validated, upon entry. // rr->NewRData // rr->newrdlength // rr->UpdateCallback extern mStatus uDNS_UpdateRecord(mDNS *m, AuthRecord *rr); extern void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q); extern mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr); extern mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt); extern mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question); extern mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question); extern mStatus mDNS_StartNATOperation_internal(mDNS *const m, NATTraversalInfo *traversal); extern void RecordRegistrationGotZoneData(mDNS *const m, mStatus err, const ZoneData *zoneData); extern mStatus uDNS_DeregisterRecord(mDNS *const m, AuthRecord *const rr); extern const domainname *GetServiceTarget(mDNS *m, AuthRecord *const rr); // integer fields of msg header must be in HOST byte order before calling this routine extern void uDNS_ReceiveMsg(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end, const mDNSAddr *const srcaddr, const mDNSIPPort srcport); extern void uDNS_Tasks(mDNS *const m); extern void UpdateAllSRVRecords(mDNS *m); extern void CheckNATMappings(mDNS *m); extern mStatus uDNS_SetupDNSConfig(mDNS *const m); // uDNS_SetupWABQueries reads search domains from the platform layer and starts the Wide Area Bonjour // (WAB) domain enumeration queries if necessary. #define UDNS_WAB_BROWSE_QUERY 0x00000001 // Browse queries (b, db) #define UDNS_WAB_LBROWSE_QUERY 0x00000002 // Browse queries (lb) #define UDNS_WAB_REG_QUERY 0x00000004 // Registration queries (r and dr) extern void uDNS_SetupWABQueries(mDNS *const m); extern void uDNS_StartWABQueries(mDNS *const m, int queryType); extern void uDNS_StopWABQueries(mDNS *const m, int queryType); extern domainname *uDNS_GetNextSearchDomain(mDNSInterfaceID InterfaceID, int *searchIndex, mDNSBool ignoreDotLocal); extern void uDNS_RestartQuestionAsTCP(mDNS *m, DNSQuestion *const q, const mDNSAddr *const srcaddr, const mDNSIPPort srcport); 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); extern DomainAuthInfo *GetAuthInfoForName_internal(mDNS *m, const domainname *const name); extern DomainAuthInfo *GetAuthInfoForQuestion(mDNS *m, const DNSQuestion *const q); extern void DisposeTCPConn(struct tcpInfo_t *tcp); // NAT traversal extern void uDNS_ReceiveNATPacket(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *pkt, mDNSu16 len); // Called for each received PCP or NAT-PMP packet extern void natTraversalHandleAddressReply(mDNS *const m, mDNSu16 err, mDNSv4Addr ExtAddr); extern void natTraversalHandlePortMapReply(mDNS *const m, NATTraversalInfo *n, const mDNSInterfaceID InterfaceID, mDNSu16 err, mDNSIPPort extport, mDNSu32 lease, NATTProtocol protocol); extern CacheRecord* mDNSCoreReceiveCacheCheck(mDNS *const m, const DNSMessage *const response, uDNS_LLQType LLQType, const mDNSu32 slot, CacheGroup *cg, CacheRecord ***cfp, mDNSInterfaceID InterfaceID); #ifdef __cplusplus } #endif #endif // __UDNS_H_