| /* |
| * |
| * Copyright (c) 2021 Project CHIP Authors |
| * |
| * 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 |
| * |
| * http://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. |
| */ |
| |
| #include "Resolver.h" |
| |
| #include <lib/core/CHIPConfig.h> |
| #include <lib/dnssd/ActiveResolveAttempts.h> |
| #include <lib/dnssd/IncrementalResolve.h> |
| #include <lib/dnssd/MinimalMdnsServer.h> |
| #include <lib/dnssd/ServiceNaming.h> |
| #include <lib/dnssd/minimal_mdns/Logging.h> |
| #include <lib/dnssd/minimal_mdns/Parser.h> |
| #include <lib/dnssd/minimal_mdns/QueryBuilder.h> |
| #include <lib/dnssd/minimal_mdns/RecordData.h> |
| #include <lib/dnssd/minimal_mdns/core/FlatAllocatedQName.h> |
| #include <lib/support/CHIPMemString.h> |
| #include <lib/support/logging/CHIPLogging.h> |
| #include <tracing/macros.h> |
| |
| // MDNS servers will receive all broadcast packets over the network. |
| // Disable 'invalid packet' messages because the are expected and common |
| // These logs are useful for debug only |
| #undef MINMDNS_RESOLVER_OVERLY_VERBOSE |
| |
| namespace chip { |
| namespace Dnssd { |
| namespace { |
| |
| constexpr size_t kMdnsMaxPacketSize = 1024; |
| constexpr uint16_t kMdnsPort = 5353; |
| |
| using namespace mdns::Minimal; |
| |
| /// Handles processing of minmdns packet data. |
| /// |
| /// Can process multiple incremental resolves based on SRV data and allows |
| /// retrieval of pending (e.g. to ask for AAAA) and complete data items. |
| /// |
| class PacketParser : private ParserDelegate |
| { |
| public: |
| PacketParser(ActiveResolveAttempts & activeResolves) : mActiveResolves(activeResolves) {} |
| |
| /// Goes through the given SRV records within a response packet |
| /// and sets up data resolution |
| void ParseSrvRecords(const BytesRange & packet); |
| |
| /// Goes through non-SRV records and feeds them through the initialized |
| /// SRV record parsing. |
| /// |
| /// Must be called AFTER ParseSrvRecords has been called. |
| void ParseNonSrvRecords(Inet::InterfaceId interface, const BytesRange & packet); |
| |
| IncrementalResolver * ResolverBegin() { return mResolvers; } |
| IncrementalResolver * ResolverEnd() { return mResolvers + kMinMdnsNumParallelResolvers; } |
| |
| private: |
| // ParserDelegate implementation |
| void OnHeader(ConstHeaderRef & header) override; |
| void OnQuery(const QueryData & data) override; |
| void OnResource(ResourceType type, const ResourceData & data) override; |
| |
| /// Called IFF data is of SRV type and we are in SRV initialization state |
| /// |
| /// Initializes a resolver with the given SRV content as long as |
| /// inactive resolvers exist. |
| void ParseSRVResource(const ResourceData & data); |
| |
| /// Called IFF parsing state is in RecordParsing |
| /// |
| /// Forwards the resource to all active resolvers. |
| void ParseResource(const ResourceData & data); |
| |
| enum class RecordParsingState |
| { |
| kIdle, |
| kSrvInitialization, |
| kRecordParsing, |
| }; |
| |
| static constexpr size_t kMinMdnsNumParallelResolvers = CHIP_CONFIG_MINMDNS_MAX_PARALLEL_RESOLVES; |
| |
| // Individual parse set |
| bool mIsResponse = false; |
| Inet::InterfaceId mInterfaceId = Inet::InterfaceId::Null(); |
| BytesRange mPacketRange; |
| RecordParsingState mParsingState = RecordParsingState::kIdle; |
| |
| // resolvers kept between parse steps |
| ActiveResolveAttempts & mActiveResolves; |
| IncrementalResolver mResolvers[kMinMdnsNumParallelResolvers]; |
| }; |
| |
| void PacketParser::OnHeader(ConstHeaderRef & header) |
| { |
| mIsResponse = header.GetFlags().IsResponse(); |
| |
| #ifdef MINMDNS_RESOLVER_OVERLY_VERBOSE |
| if (header.GetFlags().IsTruncated()) |
| { |
| // MinMdns does not cache data, so receiving piecewise data does not work |
| ChipLogError(Discovery, "Truncated responses not supported for address resolution"); |
| } |
| #endif |
| } |
| |
| void PacketParser::OnQuery(const QueryData & data) |
| { |
| // Ignore queries: |
| // - unicast answers will include the corresponding query in the answer |
| // packet, however that is not interesting for the resolver. |
| } |
| |
| void PacketParser::OnResource(ResourceType type, const ResourceData & data) |
| { |
| if (!mIsResponse) |
| { |
| return; |
| } |
| |
| switch (mParsingState) |
| { |
| case RecordParsingState::kSrvInitialization: { |
| if (data.GetType() != QType::SRV) |
| { |
| return; |
| } |
| mdns::Minimal::Logging::LogReceivedResource(data); |
| ParseSRVResource(data); |
| break; |
| } |
| case RecordParsingState::kRecordParsing: |
| if (data.GetType() != QType::SRV) |
| { |
| // SRV packets logged during 'SrvInitialization' phase |
| mdns::Minimal::Logging::LogReceivedResource(data); |
| } |
| ParseResource(data); |
| break; |
| case RecordParsingState::kIdle: |
| ChipLogError(Discovery, "Illegal state: received DNSSD resource while IDLE"); |
| break; |
| } |
| } |
| |
| void PacketParser::ParseResource(const ResourceData & data) |
| { |
| for (auto & resolver : mResolvers) |
| { |
| if (resolver.IsActive()) |
| { |
| CHIP_ERROR err = resolver.OnRecord(mInterfaceId, data, mPacketRange); |
| |
| // |
| // CHIP_ERROR_NO_MEMORY usually gets returned when we have no more memory available to hold the |
| // resolved data. This gets emitted fairly frequently in dense environments or when receiving records |
| // from devices with lots of interfaces. Consequently, don't log that unless we have DNS verbosity |
| // logging enabled. |
| // |
| if (err != CHIP_NO_ERROR) |
| { |
| #if !CHIP_MINMDNS_HIGH_VERBOSITY |
| if (err != CHIP_ERROR_NO_MEMORY) |
| #endif |
| ChipLogError(Discovery, "DNSSD parse error: %" CHIP_ERROR_FORMAT, err.Format()); |
| } |
| } |
| } |
| |
| // Once an IP address is received, stop requesting it. |
| if (data.GetType() == QType::AAAA) |
| { |
| mActiveResolves.CompleteIpResolution(data.GetName()); |
| } |
| } |
| |
| void PacketParser::ParseSRVResource(const ResourceData & data) |
| { |
| SrvRecord srv; |
| if (!srv.Parse(data.GetData(), mPacketRange)) |
| { |
| ChipLogError(Discovery, "Packet data reporter failed to parse SRV record"); |
| return; |
| } |
| |
| for (auto & resolver : mResolvers) |
| { |
| if (resolver.IsActive() && (resolver.GetRecordName() == data.GetName())) |
| { |
| ChipLogDetail(Discovery, "SRV record already actively processed."); |
| return; |
| } |
| } |
| |
| for (auto & resolver : mResolvers) |
| { |
| if (resolver.IsActive()) |
| { |
| continue; |
| } |
| |
| CHIP_ERROR err = resolver.InitializeParsing(data.GetName(), data.GetTtlSeconds(), srv); |
| if (err != CHIP_NO_ERROR) |
| { |
| // Receiving records that we do not need to parse is normal: |
| // MinMDNS may receive all DNSSD packets on the network, only |
| // interested in a subset that is matter-specific |
| #ifdef MINMDNS_RESOLVER_OVERLY_VERBOSE |
| ChipLogError(Discovery, "Could not start SRV record processing: %" CHIP_ERROR_FORMAT, err.Format()); |
| #endif |
| } |
| |
| // Done finding an inactive resolver and attempting to use it. |
| return; |
| } |
| |
| #if CHIP_MINMDNS_HIGH_VERBOSITY |
| ChipLogError(Discovery, "Insufficient parsers to process all SRV entries."); |
| #endif |
| } |
| |
| void PacketParser::ParseSrvRecords(const BytesRange & packet) |
| { |
| MATTER_TRACE_SCOPE("Searching SRV Records", "PacketParser"); |
| |
| mParsingState = RecordParsingState::kSrvInitialization; |
| mPacketRange = packet; |
| |
| if (!ParsePacket(packet, this)) |
| { |
| ChipLogError(Discovery, "DNSSD packet parsing failed (for SRV records)"); |
| } |
| |
| mParsingState = RecordParsingState::kIdle; |
| } |
| |
| void PacketParser::ParseNonSrvRecords(Inet::InterfaceId interface, const BytesRange & packet) |
| { |
| MATTER_TRACE_SCOPE("Searching NON-SRV Records", "PacketParser"); |
| |
| mParsingState = RecordParsingState::kRecordParsing; |
| mPacketRange = packet; |
| mInterfaceId = interface; |
| |
| if (!ParsePacket(packet, this)) |
| { |
| ChipLogError(Discovery, "DNSSD packet parsing failed (for non-srv records)"); |
| } |
| |
| mParsingState = RecordParsingState::kIdle; |
| } |
| |
| class MinMdnsResolver : public Resolver, public MdnsPacketDelegate |
| { |
| public: |
| MinMdnsResolver() : mActiveResolves(&chip::System::SystemClock()), mPacketParser(mActiveResolves) |
| { |
| GlobalMinimalMdnsServer::Instance().SetResponseDelegate(this); |
| } |
| ~MinMdnsResolver() { SetDiscoveryContext(nullptr); } |
| |
| //// MdnsPacketDelegate implementation |
| void OnMdnsPacketData(const BytesRange & data, const chip::Inet::IPPacketInfo * info) override; |
| |
| ///// Resolver implementation |
| CHIP_ERROR Init(chip::Inet::EndPointManager<chip::Inet::UDPEndPoint> * udpEndPointManager) override; |
| bool IsInitialized() override; |
| void Shutdown() override; |
| void SetOperationalDelegate(OperationalResolveDelegate * delegate) override { mOperationalDelegate = delegate; } |
| CHIP_ERROR ResolveNodeId(const PeerId & peerId) override; |
| void NodeIdResolutionNoLongerNeeded(const PeerId & peerId) override; |
| CHIP_ERROR StartDiscovery(DiscoveryType type, DiscoveryFilter filter, DiscoveryContext & context) override; |
| CHIP_ERROR StopDiscovery(DiscoveryContext & context) override; |
| CHIP_ERROR ReconfirmRecord(const char * hostname, Inet::IPAddress address, Inet::InterfaceId interfaceId) override; |
| |
| private: |
| OperationalResolveDelegate * mOperationalDelegate = nullptr; |
| DiscoveryContext * mDiscoveryContext = nullptr; |
| System::Layer * mSystemLayer = nullptr; |
| ActiveResolveAttempts mActiveResolves; |
| PacketParser mPacketParser; |
| |
| void SetDiscoveryContext(DiscoveryContext * context); |
| void ScheduleIpAddressResolve(SerializedQNameIterator hostName); |
| |
| CHIP_ERROR SendAllPendingQueries(); |
| CHIP_ERROR ScheduleRetries(); |
| |
| /// Prepare a query for the given schedule attempt |
| CHIP_ERROR BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt & attempt); |
| |
| /// Prepare a query for specific resolve types |
| CHIP_ERROR BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::Browse & data, bool firstSend); |
| CHIP_ERROR BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::Resolve & data, bool firstSend); |
| CHIP_ERROR BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::IpResolve & data, bool firstSend); |
| |
| /// Clear any incremental resolver that is not waiting for a AAAA address. |
| void ExpireIncrementalResolvers(); |
| void AdvancePendingResolverStates(); |
| |
| static void RetryCallback(System::Layer *, void * self); |
| |
| CHIP_ERROR BrowseNodes(DiscoveryType type, DiscoveryFilter subtype); |
| template <typename... Args> |
| mdns::Minimal::FullQName CheckAndAllocateQName(Args &&... parts) |
| { |
| size_t requiredSize = mdns::Minimal::FlatAllocatedQName::RequiredStorageSize(parts...); |
| if (requiredSize > kMaxQnameSize) |
| { |
| return mdns::Minimal::FullQName(); |
| } |
| return mdns::Minimal::FlatAllocatedQName::Build(qnameStorage, parts...); |
| } |
| static constexpr int kMaxQnameSize = 100; |
| char qnameStorage[kMaxQnameSize]; |
| }; |
| |
| void MinMdnsResolver::SetDiscoveryContext(DiscoveryContext * context) |
| { |
| if (mDiscoveryContext != nullptr) |
| { |
| mDiscoveryContext->Release(); |
| } |
| |
| if (context != nullptr) |
| { |
| context->Retain(); |
| } |
| |
| mDiscoveryContext = context; |
| } |
| |
| void MinMdnsResolver::ScheduleIpAddressResolve(SerializedQNameIterator hostName) |
| { |
| HeapQName target(hostName); |
| if (!target.IsOk()) |
| { |
| ChipLogError(Discovery, "Memory allocation error for IP address resolution"); |
| return; |
| } |
| mActiveResolves.MarkPending(ActiveResolveAttempts::ScheduledAttempt::IpResolve(std::move(target))); |
| } |
| |
| void MinMdnsResolver::AdvancePendingResolverStates() |
| { |
| MATTER_TRACE_SCOPE("Advance pending resolve states", "MinMdnsResolver"); |
| |
| for (IncrementalResolver * resolver = mPacketParser.ResolverBegin(); resolver != mPacketParser.ResolverEnd(); resolver++) |
| { |
| if (!resolver->IsActive()) |
| { |
| continue; |
| } |
| |
| IncrementalResolver::RequiredInformationFlags missing = resolver->GetMissingRequiredInformation(); |
| |
| if (missing.Has(IncrementalResolver::RequiredInformationBitFlags::kIpAddress)) |
| { |
| if (resolver->IsActiveCommissionParse()) |
| { |
| // Browse wants IP addresses |
| ScheduleIpAddressResolve(resolver->GetTargetHostName()); |
| } |
| else if (mActiveResolves.ShouldResolveIpAddress(resolver->OperationalParsePeerId())) |
| { |
| // Keep searching for IP addresses if an active resolve needs these IP addresses |
| // otherwise ignore the data (received a SRV record without IP address, however we do not |
| // seem interested in it. Probably just a device that came online). |
| ScheduleIpAddressResolve(resolver->GetTargetHostName()); |
| } |
| else |
| { |
| // This IP address is not interesting enough to run another discovery |
| resolver->ResetToInactive(); |
| } |
| continue; |
| } |
| |
| if (missing.HasAny()) |
| { |
| // Expect either IP missing (ask for it) or done. Anything else is not handled |
| ChipLogError(Discovery, "Unexpected state: cannot advance resolver with missing information"); |
| resolver->ResetToInactive(); |
| continue; |
| } |
| |
| // SUCCESS. Call the delegates |
| if (resolver->IsActiveCommissionParse()) |
| { |
| MATTER_TRACE_SCOPE("Active commissioning delegate call", "MinMdnsResolver"); |
| DiscoveredNodeData nodeData; |
| |
| CHIP_ERROR err = resolver->Take(nodeData); |
| if (err != CHIP_NO_ERROR) |
| { |
| ChipLogError(Discovery, "Failed to take discovery result: %" CHIP_ERROR_FORMAT, err.Format()); |
| continue; |
| } |
| |
| // TODO: Ideally commissioning delegates should be aware of the |
| // node types they receive, however they are currently not |
| // so try to help out by only calling the delegate when an |
| // active browse exists. |
| // |
| // This is NOT ok and probably we should have separate comissioner |
| // or commissionable delegates or pass in a node type argument. |
| bool discoveredNodeIsRelevant = false; |
| |
| switch (resolver->GetCurrentType()) |
| { |
| case IncrementalResolver::ServiceNameType::kCommissioner: |
| discoveredNodeIsRelevant = mActiveResolves.HasBrowseFor(chip::Dnssd::DiscoveryType::kCommissionerNode); |
| break; |
| case IncrementalResolver::ServiceNameType::kCommissionable: |
| discoveredNodeIsRelevant = mActiveResolves.HasBrowseFor(chip::Dnssd::DiscoveryType::kCommissionableNode); |
| break; |
| default: |
| ChipLogError(Discovery, "Unexpected type for browse data parsing"); |
| continue; |
| } |
| |
| if (discoveredNodeIsRelevant) |
| { |
| if (mDiscoveryContext != nullptr) |
| { |
| mDiscoveryContext->OnNodeDiscovered(nodeData); |
| } |
| else |
| { |
| #if CHIP_MINMDNS_HIGH_VERBOSITY |
| ChipLogError(Discovery, "No delegate to report commissioning node discovery"); |
| #endif |
| } |
| } |
| } |
| else if (resolver->IsActiveOperationalParse()) |
| { |
| MATTER_TRACE_SCOPE("Active operational delegate call", "MinMdnsResolver"); |
| ResolvedNodeData nodeResolvedData; |
| CHIP_ERROR err = resolver->Take(nodeResolvedData); |
| |
| if (err != CHIP_NO_ERROR) |
| { |
| ChipLogError(Discovery, "Failed to take NodeData - result: %" CHIP_ERROR_FORMAT, err.Format()); |
| continue; |
| } |
| |
| if (mActiveResolves.HasBrowseFor(chip::Dnssd::DiscoveryType::kOperational)) |
| { |
| if (mDiscoveryContext != nullptr) |
| { |
| DiscoveredNodeData nodeData; |
| OperationalNodeBrowseData opNodeData; |
| |
| opNodeData.peerId = nodeResolvedData.operationalData.peerId; |
| opNodeData.hasZeroTTL = nodeResolvedData.operationalData.hasZeroTTL; |
| nodeData.Set<OperationalNodeBrowseData>(opNodeData); |
| mDiscoveryContext->OnNodeDiscovered(nodeData); |
| } |
| else |
| { |
| #if CHIP_MINMDNS_HIGH_VERBOSITY |
| ChipLogError(Discovery, "No delegate to report operational node discovery"); |
| #endif |
| } |
| } |
| |
| mActiveResolves.Complete(nodeResolvedData.operationalData.peerId); |
| if (mOperationalDelegate != nullptr) |
| { |
| mOperationalDelegate->OnOperationalNodeResolved(nodeResolvedData); |
| } |
| else |
| { |
| #if CHIP_MINMDNS_HIGH_VERBOSITY |
| ChipLogError(Discovery, "No delegate to report operational node discovery"); |
| #endif |
| } |
| } |
| else |
| { |
| ChipLogError(Discovery, "Unexpected state: record type unknown"); |
| resolver->ResetToInactive(); |
| } |
| } |
| } |
| |
| void MinMdnsResolver::OnMdnsPacketData(const BytesRange & data, const chip::Inet::IPPacketInfo * info) |
| { |
| MATTER_TRACE_SCOPE("Received MDNS Packet", "MinMdnsResolver"); |
| |
| // Fill up any relevant data |
| mPacketParser.ParseSrvRecords(data); |
| mPacketParser.ParseNonSrvRecords(info->Interface, data); |
| |
| AdvancePendingResolverStates(); |
| |
| ScheduleRetries(); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::Init(chip::Inet::EndPointManager<chip::Inet::UDPEndPoint> * udpEndPointManager) |
| { |
| /// Note: we do not double-check the port as we assume the APP will always use |
| /// the same udpEndPointManager and port for mDNS. |
| mSystemLayer = &udpEndPointManager->SystemLayer(); |
| |
| if (GlobalMinimalMdnsServer::Server().IsListening()) |
| { |
| return CHIP_NO_ERROR; |
| } |
| |
| return GlobalMinimalMdnsServer::Instance().StartServer(udpEndPointManager, kMdnsPort); |
| } |
| |
| bool MinMdnsResolver::IsInitialized() |
| { |
| return GlobalMinimalMdnsServer::Server().IsListening(); |
| } |
| |
| void MinMdnsResolver::Shutdown() |
| { |
| GlobalMinimalMdnsServer::Instance().ShutdownServer(); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::Browse & data, |
| bool firstSend) |
| { |
| mdns::Minimal::FullQName qname; |
| |
| switch (data.type) |
| { |
| case DiscoveryType::kOperational: |
| if (data.filter.type == DiscoveryFilterType::kCompressedFabricId) |
| { |
| char subtypeStr[Common::kSubTypeMaxLength + 1]; |
| ReturnErrorOnFailure(MakeServiceSubtype(subtypeStr, sizeof(subtypeStr), data.filter)); |
| qname = CheckAndAllocateQName(subtypeStr, kSubtypeServiceNamePart, kOperationalServiceName, kOperationalProtocol, |
| kLocalDomain); |
| } |
| else |
| { |
| qname = CheckAndAllocateQName(kOperationalServiceName, kOperationalProtocol, kLocalDomain); |
| } |
| break; |
| case DiscoveryType::kCommissionableNode: |
| if (data.filter.type == DiscoveryFilterType::kNone) |
| { |
| qname = CheckAndAllocateQName(kCommissionableServiceName, kCommissionProtocol, kLocalDomain); |
| } |
| else if (data.filter.type == DiscoveryFilterType::kInstanceName) |
| { |
| qname = CheckAndAllocateQName(data.filter.instanceName, kCommissionableServiceName, kCommissionProtocol, kLocalDomain); |
| } |
| else |
| { |
| char subtypeStr[Common::kSubTypeMaxLength + 1]; |
| ReturnErrorOnFailure(MakeServiceSubtype(subtypeStr, sizeof(subtypeStr), data.filter)); |
| qname = CheckAndAllocateQName(subtypeStr, kSubtypeServiceNamePart, kCommissionableServiceName, kCommissionProtocol, |
| kLocalDomain); |
| } |
| break; |
| case DiscoveryType::kCommissionerNode: |
| if (data.filter.type == DiscoveryFilterType::kNone) |
| { |
| qname = CheckAndAllocateQName(kCommissionerServiceName, kCommissionProtocol, kLocalDomain); |
| } |
| else |
| { |
| char subtypeStr[Common::kSubTypeMaxLength + 1]; |
| ReturnErrorOnFailure(MakeServiceSubtype(subtypeStr, sizeof(subtypeStr), data.filter)); |
| qname = CheckAndAllocateQName(subtypeStr, kSubtypeServiceNamePart, kCommissionerServiceName, kCommissionProtocol, |
| kLocalDomain); |
| } |
| break; |
| case DiscoveryType::kUnknown: |
| break; |
| } |
| |
| VerifyOrReturnError(qname.nameCount, CHIP_ERROR_NO_MEMORY); |
| |
| mdns::Minimal::Query query(qname); |
| query |
| .SetClass(QClass::IN) // |
| .SetType(QType::ANY) // |
| .SetAnswerViaUnicast(firstSend) // |
| ; |
| |
| mdns::Minimal::Logging::LogSendingQuery(query); |
| builder.AddQuery(query); |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| CHIP_ERROR MinMdnsResolver::BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::Resolve & data, |
| bool firstSend) |
| { |
| char nameBuffer[kMaxOperationalServiceNameSize] = ""; |
| |
| // Node and fabricid are encoded in server names. |
| ReturnErrorOnFailure(MakeInstanceName(nameBuffer, sizeof(nameBuffer), data.peerId)); |
| |
| const char * instanceQName[] = { nameBuffer, kOperationalServiceName, kOperationalProtocol, kLocalDomain }; |
| Query query(instanceQName); |
| |
| query |
| .SetClass(QClass::IN) // |
| .SetType(QType::ANY) // |
| .SetAnswerViaUnicast(firstSend) // |
| ; |
| |
| mdns::Minimal::Logging::LogSendingQuery(query); |
| builder.AddQuery(query); |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| CHIP_ERROR MinMdnsResolver::BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt::IpResolve & data, |
| bool firstSend) |
| { |
| |
| Query query(data.hostName.Content()); |
| |
| query |
| .SetClass(QClass::IN) // |
| .SetType(QType::AAAA) // |
| .SetAnswerViaUnicast(firstSend) // |
| ; |
| |
| mdns::Minimal::Logging::LogSendingQuery(query); |
| builder.AddQuery(query); |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| CHIP_ERROR MinMdnsResolver::BuildQuery(QueryBuilder & builder, const ActiveResolveAttempts::ScheduledAttempt & attempt) |
| { |
| if (attempt.IsResolve()) |
| { |
| ReturnErrorOnFailure(BuildQuery(builder, attempt.ResolveData(), attempt.firstSend)); |
| } |
| else if (attempt.IsBrowse()) |
| { |
| ReturnErrorOnFailure(BuildQuery(builder, attempt.BrowseData(), attempt.firstSend)); |
| } |
| else if (attempt.IsIpResolve()) |
| { |
| ReturnErrorOnFailure(BuildQuery(builder, attempt.IpResolveData(), attempt.firstSend)); |
| } |
| else |
| { |
| return CHIP_ERROR_INVALID_ARGUMENT; |
| } |
| |
| VerifyOrReturnError(builder.Ok(), CHIP_ERROR_INTERNAL); |
| return CHIP_NO_ERROR; |
| } |
| |
| CHIP_ERROR MinMdnsResolver::SendAllPendingQueries() |
| { |
| while (true) |
| { |
| std::optional<ActiveResolveAttempts::ScheduledAttempt> resolve = mActiveResolves.NextScheduled(); |
| |
| if (!resolve.has_value()) |
| { |
| break; |
| } |
| |
| System::PacketBufferHandle buffer = System::PacketBufferHandle::New(kMdnsMaxPacketSize); |
| VerifyOrReturnError(!buffer.IsNull(), CHIP_ERROR_NO_MEMORY); |
| |
| QueryBuilder builder(std::move(buffer)); |
| builder.Header().SetMessageId(0); |
| |
| ReturnErrorOnFailure(BuildQuery(builder, *resolve)); |
| |
| if (resolve->firstSend) |
| { |
| ReturnErrorOnFailure(GlobalMinimalMdnsServer::Server().BroadcastUnicastQuery(builder.ReleasePacket(), kMdnsPort)); |
| } |
| else |
| { |
| ReturnErrorOnFailure(GlobalMinimalMdnsServer::Server().BroadcastSend(builder.ReleasePacket(), kMdnsPort)); |
| } |
| } |
| |
| ExpireIncrementalResolvers(); |
| |
| return ScheduleRetries(); |
| } |
| |
| void MinMdnsResolver::ExpireIncrementalResolvers() |
| { |
| // once all queries are sent, if any SRV cannot receive AAAA addresses, expire it |
| for (IncrementalResolver * resolver = mPacketParser.ResolverBegin(); resolver != mPacketParser.ResolverEnd(); resolver++) |
| { |
| if (!resolver->IsActive()) |
| { |
| continue; |
| } |
| |
| IncrementalResolver::RequiredInformationFlags missing = resolver->GetMissingRequiredInformation(); |
| if (missing.Has(IncrementalResolver::RequiredInformationBitFlags::kIpAddress)) |
| { |
| if (mActiveResolves.IsWaitingForIpResolutionFor(resolver->GetTargetHostName())) |
| { |
| continue; |
| } |
| } |
| |
| // mark as expired: not waiting for anything |
| resolver->ResetToInactive(); |
| } |
| } |
| |
| CHIP_ERROR MinMdnsResolver::StartDiscovery(DiscoveryType type, DiscoveryFilter filter, DiscoveryContext & context) |
| { |
| // minmdns currently supports only one discovery context at a time so override the previous context |
| SetDiscoveryContext(&context); |
| |
| return BrowseNodes(type, filter); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::StopDiscovery(DiscoveryContext & context) |
| { |
| SetDiscoveryContext(nullptr); |
| |
| return mActiveResolves.CompleteAllBrowses(); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::ReconfirmRecord(const char * hostname, Inet::IPAddress address, Inet::InterfaceId interfaceId) |
| { |
| return CHIP_ERROR_NOT_IMPLEMENTED; |
| } |
| |
| CHIP_ERROR MinMdnsResolver::BrowseNodes(DiscoveryType type, DiscoveryFilter filter) |
| { |
| mActiveResolves.MarkPending(filter, type); |
| |
| return SendAllPendingQueries(); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::ResolveNodeId(const PeerId & peerId) |
| { |
| mActiveResolves.MarkPending(peerId); |
| |
| return SendAllPendingQueries(); |
| } |
| |
| void MinMdnsResolver::NodeIdResolutionNoLongerNeeded(const PeerId & peerId) |
| { |
| mActiveResolves.NodeIdResolutionNoLongerNeeded(peerId); |
| } |
| |
| CHIP_ERROR MinMdnsResolver::ScheduleRetries() |
| { |
| MATTER_TRACE_SCOPE("Schedule retries", "MinMdnsResolver"); |
| |
| VerifyOrReturnError(mSystemLayer != nullptr, CHIP_ERROR_INCORRECT_STATE); |
| mSystemLayer->CancelTimer(&RetryCallback, this); |
| |
| std::optional<System::Clock::Timeout> delay = mActiveResolves.GetTimeUntilNextExpectedResponse(); |
| |
| if (!delay.has_value()) |
| { |
| return CHIP_NO_ERROR; |
| } |
| |
| return mSystemLayer->StartTimer(*delay, &RetryCallback, this); |
| } |
| |
| void MinMdnsResolver::RetryCallback(System::Layer *, void * self) |
| { |
| reinterpret_cast<MinMdnsResolver *>(self)->SendAllPendingQueries(); |
| } |
| |
| MinMdnsResolver gResolver; |
| |
| } // namespace |
| |
| #if CHIP_DNSSD_DEFAULT_MINIMAL |
| |
| Resolver & GetDefaultResolver() |
| { |
| return gResolver; |
| } |
| |
| #endif // CHIP_DNSSD_DEFAULT_MINIMAL |
| |
| } // namespace Dnssd |
| } // namespace chip |
