src/platform/mt793x/DnssdImpl.cpp - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2020-2022 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 "DnssdImpl.h"
 #include "MdnsError.h"
 #include "lib/dnssd/platform/Dnssd.h"

 #include "dns_sd.h"
 #include "lwip/mld6.h"
 #include "mdns.h"
 #include <lwip/ip4_addr.h>
 #include <lwip/ip6_addr.h>

 #include "FreeRTOS.h"
 #include "event_groups.h"
 #include "lwip/sockets.h"
 #undef write
 #undef read
 #include <cstdio>
 #include <sstream>
 #include <string.h>
 #include <string>

 #include "mDNSDebug.h"
 #include "task.h"
 #include "task_def.h"
 #include <errno.h>

 #include "platform/CHIPDeviceLayer.h"
 #include <lib/support/CHIPMem.h>
 #include <lib/support/CodeUtils.h>
 #include <lib/support/SafeInt.h>
 #include <lib/support/logging/CHIPLogging.h>

 using namespace chip::Dnssd;

 extern "C" {
 extern void mDNSPlatformWriteLogRedirect(void (*)(const char *, const char *));
 }

 namespace {
 constexpr char kLocalDot[]              = "local.";
 constexpr char kProtocolTcp[]           = "._tcp";
 constexpr char kProtocolUdp[]           = "._udp";
 static constexpr uint32_t kTimeoutMilli = 3000;
 static constexpr size_t kMaxResults     = 20;

 constexpr DNSServiceFlags kRegisterFlags        = kDNSServiceFlagsNoAutoRename;
 constexpr DNSServiceFlags kBrowseFlags          = 0;
 constexpr DNSServiceFlags kGetAddrInfoFlags     = kDNSServiceFlagsTimeout | kDNSServiceFlagsShareConnection;
 constexpr DNSServiceFlags kResolveFlags         = kDNSServiceFlagsShareConnection;
 constexpr DNSServiceFlags kReconfirmRecordFlags = 0;

 bool IsSupportedProtocol(DnssdServiceProtocol protocol)
 {
     return (protocol == DnssdServiceProtocol::kDnssdProtocolUdp) || (protocol == DnssdServiceProtocol::kDnssdProtocolTcp);
 }

 uint32_t GetInterfaceId(chip::Inet::InterfaceId interfaceId)
 {
     return interfaceId.IsPresent() ? (uint32_t) (void *) interfaceId.GetPlatformInterface() : kDNSServiceInterfaceIndexAny;
 }

 std::string GetFullType(const char * type, DnssdServiceProtocol protocol)
 {
     std::ostringstream typeBuilder;
     typeBuilder << type;
     typeBuilder << (protocol == DnssdServiceProtocol::kDnssdProtocolUdp ? kProtocolUdp : kProtocolTcp);
     return typeBuilder.str();
 }

 std::string GetFullType(const DnssdService * service)
 {
     return GetFullType(service->mType, service->mProtocol);
 }

 std::string GetFullTypeWithSubTypes(const char * type, DnssdServiceProtocol protocol, const char * subTypes[], size_t subTypeSize)
 {
     std::ostringstream typeBuilder;
     typeBuilder << type;
     typeBuilder << (protocol == DnssdServiceProtocol::kDnssdProtocolUdp ? kProtocolUdp : kProtocolTcp);
     for (int i = 0; i < (int) subTypeSize; i++)
     {
         typeBuilder << ",";
         typeBuilder << subTypes[i];
     }
     return typeBuilder.str();
 }

 std::string GetFullTypeWithSubTypes(const char * type, DnssdServiceProtocol protocol)
 {
     auto fullType = GetFullType(type, protocol);

     std::string subtypeDelimiter = "._sub.";
     size_t position              = fullType.find(subtypeDelimiter);
     if (position != std::string::npos)
     {
         fullType = fullType.substr(position + subtypeDelimiter.size()) + "," + fullType.substr(0, position);
     }

     return fullType;
 }

 std::string GetFullTypeWithSubTypes(const DnssdService * service)
 {
     return GetFullTypeWithSubTypes(service->mType, service->mProtocol, service->mSubTypes, service->mSubTypeSize);
 }

 std::string GetHostNameWithDomain(const char * hostname)
 {
     return std::string(hostname) + '.' + kLocalDot;
 }

 void LogOnFailure(const char * name, DNSServiceErrorType err)
 {
     if (kDNSServiceErr_NoError != err)
     {
         ChipLogError(Discovery, "%s (%s)", name, Error::ToString(err));
     }
 }

 class ScopedTXTRecord
 {
 public:
     ScopedTXTRecord() {}

     ~ScopedTXTRecord()
     {
         if (mDataSize != 0)
         {
             TXTRecordDeallocate(&mRecordRef);
         }
     }

     CHIP_ERROR Init(TextEntry * textEntries, size_t textEntrySize)
     {
         VerifyOrReturnError(textEntrySize <= kDnssdTextMaxSize, CHIP_ERROR_INVALID_ARGUMENT);

         TXTRecordCreate(&mRecordRef, sizeof(mRecordBuffer), mRecordBuffer);

         for (size_t i = 0; i < textEntrySize; i++)
         {
             TextEntry entry = textEntries[i];
             VerifyOrReturnError(chip::CanCastTo<uint8_t>(entry.mDataSize), CHIP_ERROR_INVALID_ARGUMENT);

             auto err = TXTRecordSetValue(&mRecordRef, entry.mKey, static_cast<uint8_t>(entry.mDataSize), entry.mData);
             VerifyOrReturnError(err == kDNSServiceErr_NoError, CHIP_ERROR_INVALID_ARGUMENT);
         }

         mDataSize = TXTRecordGetLength(&mRecordRef);
         if (mDataSize == 0)
         {
             TXTRecordDeallocate(&mRecordRef);
         }

         mData = TXTRecordGetBytesPtr(&mRecordRef);
         return CHIP_NO_ERROR;
     }

     uint16_t size() { return mDataSize; }
     const void * data() { return mData; }

 private:
     uint16_t mDataSize = 0;
     const void * mData = nullptr;

     TXTRecordRef mRecordRef;
     char mRecordBuffer[kDnssdTextMaxSize];
 };
 } // namespace

 namespace chip {
 namespace Dnssd {

 #define SERVICE_DOMAIN ("local")

 MdnsContexts MdnsContexts::sInstance;
 static DNSServiceRef BrowseClient = NULL;
 static TaskHandle_t gResolveTask  = NULL;
 static EventGroupHandle_t gResolveTaskWakeEvent;

 void ChipDnssdMdnsLog(const char * level, const char * msg)
 {
     ChipLogProgress(ServiceProvisioning, "%s %s", StringOrNullMarker(level), StringOrNullMarker(msg));
 }

 static void OnRegister(DNSServiceRef sdRef, DNSServiceFlags flags, DNSServiceErrorType err, const char * name, const char * type,
                        const char * domain, void * context)
 {
     ChipLogDetail(Discovery, "Mdns: %s name: %s, type: %s, domain: %s, flags: %ld", __func__, name, type, domain, flags);

     auto sdCtx = reinterpret_cast<RegisterContext *>(context);
     sdCtx->Finalize(err);
 };

 CHIP_ERROR Register(void * context, DnssdPublishCallback callback, uint32_t interfaceId, const char * type, const char * name,
                     uint16_t port, ScopedTXTRecord & record, Inet::IPAddressType addressType, const char * hostname)
 {
     ChipLogDetail(Discovery, "Registering service %s on host %s with port %u and type: %s on interface id: %" PRIu32, name,
                   hostname, port, type, interfaceId);

     RegisterContext * sdCtx = nullptr;
     if (CHIP_NO_ERROR == MdnsContexts::GetInstance().GetRegisterContextOfType(type, &sdCtx))
     {
         auto err = DNSServiceUpdateRecord(sdCtx->serviceRef, nullptr, kRegisterFlags, record.size(), record.data(), 0 /* ttl */);
         VerifyOrReturnError(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));
         return CHIP_NO_ERROR;
     }

     sdCtx = chip::Platform::New<RegisterContext>(type, name, callback, context);
     VerifyOrReturnError(nullptr != sdCtx, CHIP_ERROR_NO_MEMORY);

     DNSServiceRef sdRef;
     auto err = DNSServiceRegister(&sdRef, kRegisterFlags, interfaceId, name, type, kLocalDot, hostname, htons(port), record.size(),
                                   record.data(), OnRegister, sdCtx);
     VerifyOrReturnError(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));

     return MdnsContexts::GetInstance().Add(sdCtx, sdRef);
 }

 static void mdnsd_entry(void * not_used)
 {
     ChipLogProgress(ServiceProvisioning, "mdnsd_entry start");
     mdnsd_start();
     ChipLogProgress(ServiceProvisioning, "mdnsd_entry return");
     vTaskDelete(NULL);
 }

 CHIP_ERROR ChipDnssdInit(DnssdAsyncReturnCallback initCallback, DnssdAsyncReturnCallback errorCallback, void * context)
 {
     CHIP_ERROR error = CHIP_NO_ERROR;
 #if LWIP_IPV6
     struct netif * sta_if = netif_default;
     ip6_addr_t mld_address;
 #endif

 #if LWIP_IPV6
     sta_if->ip6_autoconfig_enabled = 1;
     ip6_addr_set_solicitednode(&mld_address, netif_ip6_addr(sta_if, 0)->addr[3]);
     mld6_joingroup(netif_ip6_addr(sta_if, 0), &mld_address);
 #endif

     ChipLogProgress(ServiceProvisioning, "create mdnsd_task");

     mDNSPlatformWriteLogRedirect(ChipDnssdMdnsLog);

     // xTaskHandle create mDNS daemon task
     if (pdPASS != xTaskCreate(mdnsd_entry, "mdnsd", (15 * 1024) / sizeof(portSTACK_TYPE), NULL, TASK_PRIORITY_NORMAL, NULL))
     {
         ChipLogProgress(ServiceProvisioning, "Cannot create mdnsd_task");
         error = CHIP_ERROR_INTERNAL;
     }

     initCallback(context, error);

     return error;
 }

 void ChipDnssdShutdown(void)
 {
     ChipLogProgress(ServiceProvisioning, "shutdown mdnsd_task not implemented");
 }

 static const char * GetProtocolString(DnssdServiceProtocol protocol)
 {
     return protocol == DnssdServiceProtocol::kDnssdProtocolTcp ? "_tcp" : "_udp";
 }

 CHIP_ERROR ChipDnssdPublishService(const DnssdService * service, DnssdPublishCallback callback, void * context)
 {
     VerifyOrReturnError(service != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
     VerifyOrReturnError(IsSupportedProtocol(service->mProtocol), CHIP_ERROR_INVALID_ARGUMENT);
     VerifyOrReturnError(callback != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
     VerifyOrReturnError(strcmp(service->mHostName, "") != 0, CHIP_ERROR_INVALID_ARGUMENT);

     ScopedTXTRecord record;
     ReturnErrorOnFailure(record.Init(service->mTextEntries, service->mTextEntrySize));

     auto regtype     = GetFullTypeWithSubTypes(service);
     auto interfaceId = GetInterfaceId(service->mInterface);
     auto hostname    = GetHostNameWithDomain(service->mHostName);

     return Register(context, callback, interfaceId, regtype.c_str(), service->mName, service->mPort, record, service->mAddressType,
                     hostname.c_str());
 }

 CHIP_ERROR ChipDnssdRemoveServices()
 {
     auto err = MdnsContexts::GetInstance().RemoveAllOfType(ContextType::Register);
     if (CHIP_ERROR_KEY_NOT_FOUND == err)
     {
         err = CHIP_NO_ERROR;
     }
     return err;
 }

 CHIP_ERROR ChipDnssdFinalizeServiceUpdate()
 {
     return CHIP_NO_ERROR;
 }

 void ChipDNSServiceBrowseReply(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
                                const char * serviceName, const char * regtype, const char * replyDomain, void * context)
 {
     DnssdBrowseCallback ChipBrowseHandler = (DnssdBrowseCallback) context;
     DnssdService service;

     ChipLogProgress(ServiceProvisioning, "ChipDNSServiceBrowseReply %s", StringOrNullMarker(serviceName));
     strcpy(service.mName, serviceName);

     ChipBrowseHandler(NULL, &service, 1, true, CHIP_NO_ERROR);
 }

 CHIP_ERROR ChipDnssdBrowse(const char * type, DnssdServiceProtocol protocol, chip::Inet::IPAddressType addressType,
                            chip::Inet::InterfaceId interface, DnssdBrowseCallback callback, void * context,
                            intptr_t * browseIdentifier)
 {
     CHIP_ERROR error = CHIP_NO_ERROR;
     DNSServiceErrorType err;
     char ServiceType[kDnssdTypeMaxSize + 10] = { 0 };

     (void) addressType;
     ChipLogProgress(ServiceProvisioning, "ChipDnssdBrowse %s", StringOrNullMarker(type));
     strcpy(ServiceType, type);
     strcat(ServiceType, ".");
     strcat(ServiceType, GetProtocolString(protocol));
     err = DNSServiceBrowse(&BrowseClient, 0, 0, ServiceType, SERVICE_DOMAIN, ChipDNSServiceBrowseReply, (void *) callback);
     ChipLogProgress(ServiceProvisioning, "DNSServiceBrowse %d", (int) err);
     if (err)
     {
         error = CHIP_ERROR_INTERNAL;
     }
     else
     {
         *browseIdentifier = reinterpret_cast<intptr_t>(nullptr);
     }
     return error;
 }

 CHIP_ERROR ChipDnssdStopBrowse(intptr_t browseIdentifier)
 {
     return CHIP_ERROR_NOT_IMPLEMENTED;
 }

 static void resolve_client_task(void * parameter)
 {
     EventBits_t uxBits;
     struct timeval tv;
     int result;
     int fd;
     fd_set readfds;

     while (1)
     {
         int nfds = 0;
         FD_ZERO(&readfds);
         nfds = MdnsContexts::GetInstance().GetSelectFd(&readfds);

         if (nfds == 0)
         {
             uxBits = xEventGroupWaitBits(gResolveTaskWakeEvent, 1, pdTRUE, pdFALSE, portMAX_DELAY);
             continue;
         }

         tv.tv_sec  = 0;
         tv.tv_usec = 100000; // 100ms

         result = select(nfds + 1, &readfds, (fd_set *) NULL, (fd_set *) NULL, &tv);
         if (result > 0)
         {
             DNSServiceErrorType error = kDNSServiceErr_NoError;

             for (fd = 0; fd <= nfds; ++fd)
             {
                 if (FD_ISSET(fd, &readfds))
                 {
                     DNSServiceRef resolveClient = NULL;
                     void * context              = MdnsContexts::GetInstance().GetBySockFd(fd);
                     if (context)
                     {
                         auto sdCtx = reinterpret_cast<ResolveContext *>(context);
                         error      = DNSServiceProcessResult(sdCtx->serviceRef);
                         {
                             mdnslogInfo("DNSServiceProcessResult(%d) returned %d\n", fd, error);
                         }
                     } // if context
                 }
             } // for
         }
         else
         {
             // remove timeout contexts
             for (fd = 0; fd <= nfds; ++fd)
             {
                 GenericContext * context = MdnsContexts::GetInstance().GetBySockFd(fd);
                 if (context && context->mSelectCount > 10)
                 {
                     context->Finalize(kDNSServiceErr_Timeout);
                 }
             }
         }
     } // while

     gResolveTask = NULL;
     vTaskDelete(NULL);
 }

 static void OnGetAddrInfo(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceId, DNSServiceErrorType err,
                           const char * hostname, const struct sockaddr * address, uint32_t ttl, void * context)
 {
     ChipLogProgress(ServiceProvisioning, "DNSServiceGetAddrInfo: OnGetAddrInfo");

     auto sdCtx = reinterpret_cast<ResolveContext *>(context);
     ReturnOnFailure(MdnsContexts::GetInstance().Has(sdCtx));

     if (kDNSServiceErr_NoError == err)
     {
         sdCtx->OnNewAddress(interfaceId, address);
     }

     if (!(flags & kDNSServiceFlagsMoreComing))
     {
         VerifyOrReturn(sdCtx->HasAddress(), sdCtx->Finalize(kDNSServiceErr_BadState));
         sdCtx->Finalize();
     }
 }

 static void GetAddrInfo(ResolveContext * sdCtx)
 {
     ChipLogProgress(ServiceProvisioning, "ChipDNSServiceResolveReply: GetAddrInfo");

     int dns_fd;
     auto protocol = sdCtx->protocol;

     for (auto & interface : sdCtx->interfaces)
     {
         DNSServiceRef resolveClient = NULL;
         auto interfaceId            = interface.first;
         auto hostname               = interface.second.fullyQualifiedDomainName.c_str();

         DNSServiceRefDeallocate(sdCtx->serviceRef);

         auto err          = DNSServiceGetAddrInfo(&resolveClient, 0, interfaceId, protocol, hostname, OnGetAddrInfo, sdCtx);
         sdCtx->serviceRef = resolveClient;
         VerifyOrReturn(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));
     }
 }

 void ChipDNSServiceResolveReply(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
                                 const char * fullname, const char * hosttarget, uint16_t port,
                                 /* In network byte order */ uint16_t txtLen, const unsigned char * txtRecord, void * context)
 {
     ChipLogProgress(ServiceProvisioning, "ChipDNSServiceResolveReply");
     if (context)
     {
         auto sdCtx = reinterpret_cast<ResolveContext *>(context);

         sdCtx->OnNewInterface(interfaceIndex, fullname, hosttarget, port, txtLen, txtRecord);
         if (kDNSServiceInterfaceIndexLocalOnly == interfaceIndex)
         {
             sdCtx->OnNewLocalOnlyAddress();
             sdCtx->Finalize();
             return;
         }
         if (!(flags & kDNSServiceFlagsMoreComing))
         {
             VerifyOrReturn(sdCtx->HasInterface(), sdCtx->Finalize(kDNSServiceErr_BadState));
             GetAddrInfo(sdCtx);
         }
     }
 }

 CHIP_ERROR ChipDnssdResolve(DnssdService * service, chip::Inet::InterfaceId interface, DnssdResolveCallback callback,
                             void * context)
 {
     DNSServiceRef resolveClient = NULL;
     CHIP_ERROR error            = CHIP_NO_ERROR;
     DNSServiceErrorType err;
     char ServiceType[kDnssdTypeMaxSize + 10] = { 0 };
     int dns_fd;
     uint32_t interfaceIndex = GetInterfaceId(interface);

     ChipLogProgress(ServiceProvisioning, "ChipDnssdResolve %s", service->mName);
     strcpy(ServiceType, service->mType);
     strcat(ServiceType, ".");
     strcat(ServiceType, GetProtocolString(service->mProtocol));

     auto sdCtx = chip::Platform::New<ResolveContext>(context, callback, service->mAddressType);
     VerifyOrReturnError(nullptr != sdCtx, CHIP_ERROR_NO_MEMORY);

     err = DNSServiceResolve(&resolveClient, 0, interfaceIndex, service->mName, ServiceType, SERVICE_DOMAIN,
                             ChipDNSServiceResolveReply, sdCtx);
     ChipLogProgress(ServiceProvisioning, "DNSServiceResolve %d", (int) err);
     if (err)
     {
         return CHIP_ERROR_INTERNAL;
     }

     sdCtx->serviceRef = resolveClient;
     error             = MdnsContexts::GetInstance().Add(sdCtx, sdCtx->serviceRef);
     if (error == CHIP_NO_ERROR)
     {
         if (gResolveTask == NULL)
         {
             gResolveTaskWakeEvent = xEventGroupCreate();
             if (gResolveTaskWakeEvent == NULL)
             {
                 ChipLogProgress(ServiceProvisioning, "Cannot create resolve_task event group");
                 return CHIP_ERROR_INTERNAL;
             }

             if (pdPASS !=
                 xTaskCreate(resolve_client_task, "mdnsr", (15 * 1024) / sizeof(portSTACK_TYPE), (void *) service,
                             TASK_PRIORITY_NORMAL, &gResolveTask))
             {
                 ChipLogProgress(ServiceProvisioning, "Cannot create resolve_task");
                 return CHIP_ERROR_INTERNAL;
             }
         }
         else
         {
             // wake up task
             xEventGroupSetBits(gResolveTaskWakeEvent, 1);
         }
     }

     return error;
 }

 void ChipDnssdResolveNoLongerNeeded(const char * instanceName) {}

 CHIP_ERROR ChipDnssdReconfirmRecord(const char * hostname, chip::Inet::IPAddress address, chip::Inet::InterfaceId interface)
 {
     return CHIP_ERROR_NOT_IMPLEMENTED;
 }

 } // namespace Dnssd
 } // namespace chip
	/*
	*
	* Copyright (c) 2020-2022 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 "DnssdImpl.h"
	#include "MdnsError.h"
	#include "lib/dnssd/platform/Dnssd.h"

	#include "dns_sd.h"
	#include "lwip/mld6.h"
	#include "mdns.h"
	#include <lwip/ip4_addr.h>
	#include <lwip/ip6_addr.h>

	#include "FreeRTOS.h"
	#include "event_groups.h"
	#include "lwip/sockets.h"
	#undef write
	#undef read
	#include <cstdio>
	#include <sstream>
	#include <string.h>
	#include <string>

	#include "mDNSDebug.h"
	#include "task.h"
	#include "task_def.h"
	#include <errno.h>

	#include "platform/CHIPDeviceLayer.h"
	#include <lib/support/CHIPMem.h>
	#include <lib/support/CodeUtils.h>
	#include <lib/support/SafeInt.h>
	#include <lib/support/logging/CHIPLogging.h>

	using namespace chip::Dnssd;

	extern "C" {
	extern void mDNSPlatformWriteLogRedirect(void ()(const char , const char *));
	}

	namespace {
	constexpr char kLocalDot[] = "local.";
	constexpr char kProtocolTcp[] = "._tcp";
	constexpr char kProtocolUdp[] = "._udp";
	static constexpr uint32_t kTimeoutMilli = 3000;
	static constexpr size_t kMaxResults = 20;

	constexpr DNSServiceFlags kRegisterFlags = kDNSServiceFlagsNoAutoRename;
	constexpr DNSServiceFlags kBrowseFlags = 0;
	constexpr DNSServiceFlags kGetAddrInfoFlags = kDNSServiceFlagsTimeout \| kDNSServiceFlagsShareConnection;
	constexpr DNSServiceFlags kResolveFlags = kDNSServiceFlagsShareConnection;
	constexpr DNSServiceFlags kReconfirmRecordFlags = 0;

	bool IsSupportedProtocol(DnssdServiceProtocol protocol)
	{
	return (protocol == DnssdServiceProtocol::kDnssdProtocolUdp) \|\| (protocol == DnssdServiceProtocol::kDnssdProtocolTcp);
	}

	uint32_t GetInterfaceId(chip::Inet::InterfaceId interfaceId)
	{
	return interfaceId.IsPresent() ? (uint32_t) (void *) interfaceId.GetPlatformInterface() : kDNSServiceInterfaceIndexAny;
	}

	std::string GetFullType(const char * type, DnssdServiceProtocol protocol)
	{
	std::ostringstream typeBuilder;
	typeBuilder << type;
	typeBuilder << (protocol == DnssdServiceProtocol::kDnssdProtocolUdp ? kProtocolUdp : kProtocolTcp);
	return typeBuilder.str();
	}

	std::string GetFullType(const DnssdService * service)
	{
	return GetFullType(service->mType, service->mProtocol);
	}

	std::string GetFullTypeWithSubTypes(const char * type, DnssdServiceProtocol protocol, const char * subTypes[], size_t subTypeSize)
	{
	std::ostringstream typeBuilder;
	typeBuilder << type;
	typeBuilder << (protocol == DnssdServiceProtocol::kDnssdProtocolUdp ? kProtocolUdp : kProtocolTcp);
	for (int i = 0; i < (int) subTypeSize; i++)
	{
	typeBuilder << ",";
	typeBuilder << subTypes[i];
	}
	return typeBuilder.str();
	}

	std::string GetFullTypeWithSubTypes(const char * type, DnssdServiceProtocol protocol)
	{
	auto fullType = GetFullType(type, protocol);

	std::string subtypeDelimiter = "._sub.";
	size_t position = fullType.find(subtypeDelimiter);
	if (position != std::string::npos)
	{
	fullType = fullType.substr(position + subtypeDelimiter.size()) + "," + fullType.substr(0, position);
	}

	return fullType;
	}

	std::string GetFullTypeWithSubTypes(const DnssdService * service)
	{
	return GetFullTypeWithSubTypes(service->mType, service->mProtocol, service->mSubTypes, service->mSubTypeSize);
	}

	std::string GetHostNameWithDomain(const char * hostname)
	{
	return std::string(hostname) + '.' + kLocalDot;
	}

	void LogOnFailure(const char * name, DNSServiceErrorType err)
	{
	if (kDNSServiceErr_NoError != err)
	{
	ChipLogError(Discovery, "%s (%s)", name, Error::ToString(err));
	}
	}

	class ScopedTXTRecord
	{
	public:
	ScopedTXTRecord() {}

	~ScopedTXTRecord()
	{
	if (mDataSize != 0)
	{
	TXTRecordDeallocate(&mRecordRef);
	}
	}

	CHIP_ERROR Init(TextEntry * textEntries, size_t textEntrySize)
	{
	VerifyOrReturnError(textEntrySize <= kDnssdTextMaxSize, CHIP_ERROR_INVALID_ARGUMENT);

	TXTRecordCreate(&mRecordRef, sizeof(mRecordBuffer), mRecordBuffer);

	for (size_t i = 0; i < textEntrySize; i++)
	{
	TextEntry entry = textEntries[i];
	VerifyOrReturnError(chip::CanCastTo<uint8_t>(entry.mDataSize), CHIP_ERROR_INVALID_ARGUMENT);

	auto err = TXTRecordSetValue(&mRecordRef, entry.mKey, static_cast<uint8_t>(entry.mDataSize), entry.mData);
	VerifyOrReturnError(err == kDNSServiceErr_NoError, CHIP_ERROR_INVALID_ARGUMENT);
	}

	mDataSize = TXTRecordGetLength(&mRecordRef);
	if (mDataSize == 0)
	{
	TXTRecordDeallocate(&mRecordRef);
	}

	mData = TXTRecordGetBytesPtr(&mRecordRef);
	return CHIP_NO_ERROR;
	}

	uint16_t size() { return mDataSize; }
	const void * data() { return mData; }

	private:
	uint16_t mDataSize = 0;
	const void * mData = nullptr;

	TXTRecordRef mRecordRef;
	char mRecordBuffer[kDnssdTextMaxSize];
	};
	} // namespace

	namespace chip {
	namespace Dnssd {

	#define SERVICE_DOMAIN ("local")

	MdnsContexts MdnsContexts::sInstance;
	static DNSServiceRef BrowseClient = NULL;
	static TaskHandle_t gResolveTask = NULL;
	static EventGroupHandle_t gResolveTaskWakeEvent;

	void ChipDnssdMdnsLog(const char * level, const char * msg)
	{
	ChipLogProgress(ServiceProvisioning, "%s %s", StringOrNullMarker(level), StringOrNullMarker(msg));
	}

	static void OnRegister(DNSServiceRef sdRef, DNSServiceFlags flags, DNSServiceErrorType err, const char * name, const char * type,
	const char * domain, void * context)
	{
	ChipLogDetail(Discovery, "Mdns: %s name: %s, type: %s, domain: %s, flags: %ld", __func__, name, type, domain, flags);

	auto sdCtx = reinterpret_cast<RegisterContext *>(context);
	sdCtx->Finalize(err);
	};

	CHIP_ERROR Register(void * context, DnssdPublishCallback callback, uint32_t interfaceId, const char * type, const char * name,
	uint16_t port, ScopedTXTRecord & record, Inet::IPAddressType addressType, const char * hostname)
	{
	ChipLogDetail(Discovery, "Registering service %s on host %s with port %u and type: %s on interface id: %" PRIu32, name,
	hostname, port, type, interfaceId);

	RegisterContext * sdCtx = nullptr;
	if (CHIP_NO_ERROR == MdnsContexts::GetInstance().GetRegisterContextOfType(type, &sdCtx))
	{
	auto err = DNSServiceUpdateRecord(sdCtx->serviceRef, nullptr, kRegisterFlags, record.size(), record.data(), 0 /* ttl */);
	VerifyOrReturnError(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));
	return CHIP_NO_ERROR;
	}

	sdCtx = chip::Platform::New<RegisterContext>(type, name, callback, context);
	VerifyOrReturnError(nullptr != sdCtx, CHIP_ERROR_NO_MEMORY);

	DNSServiceRef sdRef;
	auto err = DNSServiceRegister(&sdRef, kRegisterFlags, interfaceId, name, type, kLocalDot, hostname, htons(port), record.size(),
	record.data(), OnRegister, sdCtx);
	VerifyOrReturnError(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));

	return MdnsContexts::GetInstance().Add(sdCtx, sdRef);
	}

	static void mdnsd_entry(void * not_used)
	{
	ChipLogProgress(ServiceProvisioning, "mdnsd_entry start");
	mdnsd_start();
	ChipLogProgress(ServiceProvisioning, "mdnsd_entry return");
	vTaskDelete(NULL);
	}

	CHIP_ERROR ChipDnssdInit(DnssdAsyncReturnCallback initCallback, DnssdAsyncReturnCallback errorCallback, void * context)
	{
	CHIP_ERROR error = CHIP_NO_ERROR;
	#if LWIP_IPV6
	struct netif * sta_if = netif_default;
	ip6_addr_t mld_address;
	#endif

	#if LWIP_IPV6
	sta_if->ip6_autoconfig_enabled = 1;
	ip6_addr_set_solicitednode(&mld_address, netif_ip6_addr(sta_if, 0)->addr[3]);
	mld6_joingroup(netif_ip6_addr(sta_if, 0), &mld_address);
	#endif

	ChipLogProgress(ServiceProvisioning, "create mdnsd_task");

	mDNSPlatformWriteLogRedirect(ChipDnssdMdnsLog);

	// xTaskHandle create mDNS daemon task
	if (pdPASS != xTaskCreate(mdnsd_entry, "mdnsd", (15 * 1024) / sizeof(portSTACK_TYPE), NULL, TASK_PRIORITY_NORMAL, NULL))
	{
	ChipLogProgress(ServiceProvisioning, "Cannot create mdnsd_task");
	error = CHIP_ERROR_INTERNAL;
	}

	initCallback(context, error);

	return error;
	}

	void ChipDnssdShutdown(void)
	{
	ChipLogProgress(ServiceProvisioning, "shutdown mdnsd_task not implemented");
	}

	static const char * GetProtocolString(DnssdServiceProtocol protocol)
	{
	return protocol == DnssdServiceProtocol::kDnssdProtocolTcp ? "_tcp" : "_udp";
	}

	CHIP_ERROR ChipDnssdPublishService(const DnssdService * service, DnssdPublishCallback callback, void * context)
	{
	VerifyOrReturnError(service != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	VerifyOrReturnError(IsSupportedProtocol(service->mProtocol), CHIP_ERROR_INVALID_ARGUMENT);
	VerifyOrReturnError(callback != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	VerifyOrReturnError(strcmp(service->mHostName, "") != 0, CHIP_ERROR_INVALID_ARGUMENT);

	ScopedTXTRecord record;
	ReturnErrorOnFailure(record.Init(service->mTextEntries, service->mTextEntrySize));

	auto regtype = GetFullTypeWithSubTypes(service);
	auto interfaceId = GetInterfaceId(service->mInterface);
	auto hostname = GetHostNameWithDomain(service->mHostName);

	return Register(context, callback, interfaceId, regtype.c_str(), service->mName, service->mPort, record, service->mAddressType,
	hostname.c_str());
	}

	CHIP_ERROR ChipDnssdRemoveServices()
	{
	auto err = MdnsContexts::GetInstance().RemoveAllOfType(ContextType::Register);
	if (CHIP_ERROR_KEY_NOT_FOUND == err)
	{
	err = CHIP_NO_ERROR;
	}
	return err;
	}

	CHIP_ERROR ChipDnssdFinalizeServiceUpdate()
	{
	return CHIP_NO_ERROR;
	}

	void ChipDNSServiceBrowseReply(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
	const char * serviceName, const char * regtype, const char * replyDomain, void * context)
	{
	DnssdBrowseCallback ChipBrowseHandler = (DnssdBrowseCallback) context;
	DnssdService service;

	ChipLogProgress(ServiceProvisioning, "ChipDNSServiceBrowseReply %s", StringOrNullMarker(serviceName));
	strcpy(service.mName, serviceName);

	ChipBrowseHandler(NULL, &service, 1, true, CHIP_NO_ERROR);
	}

	CHIP_ERROR ChipDnssdBrowse(const char * type, DnssdServiceProtocol protocol, chip::Inet::IPAddressType addressType,
	chip::Inet::InterfaceId interface, DnssdBrowseCallback callback, void * context,
	intptr_t * browseIdentifier)
	{
	CHIP_ERROR error = CHIP_NO_ERROR;
	DNSServiceErrorType err;
	char ServiceType[kDnssdTypeMaxSize + 10] = { 0 };

	(void) addressType;
	ChipLogProgress(ServiceProvisioning, "ChipDnssdBrowse %s", StringOrNullMarker(type));
	strcpy(ServiceType, type);
	strcat(ServiceType, ".");
	strcat(ServiceType, GetProtocolString(protocol));
	err = DNSServiceBrowse(&BrowseClient, 0, 0, ServiceType, SERVICE_DOMAIN, ChipDNSServiceBrowseReply, (void *) callback);
	ChipLogProgress(ServiceProvisioning, "DNSServiceBrowse %d", (int) err);
	if (err)
	{
	error = CHIP_ERROR_INTERNAL;
	}
	else
	{
	*browseIdentifier = reinterpret_cast<intptr_t>(nullptr);
	}
	return error;
	}

	CHIP_ERROR ChipDnssdStopBrowse(intptr_t browseIdentifier)
	{
	return CHIP_ERROR_NOT_IMPLEMENTED;
	}

	static void resolve_client_task(void * parameter)
	{
	EventBits_t uxBits;
	struct timeval tv;
	int result;
	int fd;
	fd_set readfds;

	while (1)
	{
	int nfds = 0;
	FD_ZERO(&readfds);
	nfds = MdnsContexts::GetInstance().GetSelectFd(&readfds);

	if (nfds == 0)
	{
	uxBits = xEventGroupWaitBits(gResolveTaskWakeEvent, 1, pdTRUE, pdFALSE, portMAX_DELAY);
	continue;
	}

	tv.tv_sec = 0;
	tv.tv_usec = 100000; // 100ms

	result = select(nfds + 1, &readfds, (fd_set ) NULL, (fd_set ) NULL, &tv);
	if (result > 0)
	{
	DNSServiceErrorType error = kDNSServiceErr_NoError;

	for (fd = 0; fd <= nfds; ++fd)
	{
	if (FD_ISSET(fd, &readfds))
	{
	DNSServiceRef resolveClient = NULL;
	void * context = MdnsContexts::GetInstance().GetBySockFd(fd);
	if (context)
	{
	auto sdCtx = reinterpret_cast<ResolveContext *>(context);
	error = DNSServiceProcessResult(sdCtx->serviceRef);
	{
	mdnslogInfo("DNSServiceProcessResult(%d) returned %d\n", fd, error);
	}
	} // if context
	}
	} // for
	}
	else
	{
	// remove timeout contexts
	for (fd = 0; fd <= nfds; ++fd)
	{
	GenericContext * context = MdnsContexts::GetInstance().GetBySockFd(fd);
	if (context && context->mSelectCount > 10)
	{
	context->Finalize(kDNSServiceErr_Timeout);
	}
	}
	}
	} // while

	gResolveTask = NULL;
	vTaskDelete(NULL);
	}

	static void OnGetAddrInfo(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceId, DNSServiceErrorType err,
	const char * hostname, const struct sockaddr * address, uint32_t ttl, void * context)
	{
	ChipLogProgress(ServiceProvisioning, "DNSServiceGetAddrInfo: OnGetAddrInfo");

	auto sdCtx = reinterpret_cast<ResolveContext *>(context);
	ReturnOnFailure(MdnsContexts::GetInstance().Has(sdCtx));

	if (kDNSServiceErr_NoError == err)
	{
	sdCtx->OnNewAddress(interfaceId, address);
	}

	if (!(flags & kDNSServiceFlagsMoreComing))
	{
	VerifyOrReturn(sdCtx->HasAddress(), sdCtx->Finalize(kDNSServiceErr_BadState));
	sdCtx->Finalize();
	}
	}

	static void GetAddrInfo(ResolveContext * sdCtx)
	{
	ChipLogProgress(ServiceProvisioning, "ChipDNSServiceResolveReply: GetAddrInfo");

	int dns_fd;
	auto protocol = sdCtx->protocol;

	for (auto & interface : sdCtx->interfaces)
	{
	DNSServiceRef resolveClient = NULL;
	auto interfaceId = interface.first;
	auto hostname = interface.second.fullyQualifiedDomainName.c_str();

	DNSServiceRefDeallocate(sdCtx->serviceRef);

	auto err = DNSServiceGetAddrInfo(&resolveClient, 0, interfaceId, protocol, hostname, OnGetAddrInfo, sdCtx);
	sdCtx->serviceRef = resolveClient;
	VerifyOrReturn(kDNSServiceErr_NoError == err, sdCtx->Finalize(err));
	}
	}

	void ChipDNSServiceResolveReply(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
	const char * fullname, const char * hosttarget, uint16_t port,
	/* In network byte order / uint16_t txtLen, const unsigned char txtRecord, void * context)
	{
	ChipLogProgress(ServiceProvisioning, "ChipDNSServiceResolveReply");
	if (context)
	{
	auto sdCtx = reinterpret_cast<ResolveContext *>(context);

	sdCtx->OnNewInterface(interfaceIndex, fullname, hosttarget, port, txtLen, txtRecord);
	if (kDNSServiceInterfaceIndexLocalOnly == interfaceIndex)
	{
	sdCtx->OnNewLocalOnlyAddress();
	sdCtx->Finalize();
	return;
	}
	if (!(flags & kDNSServiceFlagsMoreComing))
	{
	VerifyOrReturn(sdCtx->HasInterface(), sdCtx->Finalize(kDNSServiceErr_BadState));
	GetAddrInfo(sdCtx);
	}
	}
	}

	CHIP_ERROR ChipDnssdResolve(DnssdService * service, chip::Inet::InterfaceId interface, DnssdResolveCallback callback,
	void * context)
	{
	DNSServiceRef resolveClient = NULL;
	CHIP_ERROR error = CHIP_NO_ERROR;
	DNSServiceErrorType err;
	char ServiceType[kDnssdTypeMaxSize + 10] = { 0 };
	int dns_fd;
	uint32_t interfaceIndex = GetInterfaceId(interface);

	ChipLogProgress(ServiceProvisioning, "ChipDnssdResolve %s", service->mName);
	strcpy(ServiceType, service->mType);
	strcat(ServiceType, ".");
	strcat(ServiceType, GetProtocolString(service->mProtocol));

	auto sdCtx = chip::Platform::New<ResolveContext>(context, callback, service->mAddressType);
	VerifyOrReturnError(nullptr != sdCtx, CHIP_ERROR_NO_MEMORY);

	err = DNSServiceResolve(&resolveClient, 0, interfaceIndex, service->mName, ServiceType, SERVICE_DOMAIN,
	ChipDNSServiceResolveReply, sdCtx);
	ChipLogProgress(ServiceProvisioning, "DNSServiceResolve %d", (int) err);
	if (err)
	{
	return CHIP_ERROR_INTERNAL;
	}

	sdCtx->serviceRef = resolveClient;
	error = MdnsContexts::GetInstance().Add(sdCtx, sdCtx->serviceRef);
	if (error == CHIP_NO_ERROR)
	{
	if (gResolveTask == NULL)
	{
	gResolveTaskWakeEvent = xEventGroupCreate();
	if (gResolveTaskWakeEvent == NULL)
	{
	ChipLogProgress(ServiceProvisioning, "Cannot create resolve_task event group");
	return CHIP_ERROR_INTERNAL;
	}

	if (pdPASS !=
	xTaskCreate(resolve_client_task, "mdnsr", (15 * 1024) / sizeof(portSTACK_TYPE), (void *) service,
	TASK_PRIORITY_NORMAL, &gResolveTask))
	{
	ChipLogProgress(ServiceProvisioning, "Cannot create resolve_task");
	return CHIP_ERROR_INTERNAL;
	}
	}
	else
	{
	// wake up task
	xEventGroupSetBits(gResolveTaskWakeEvent, 1);
	}
	}

	return error;
	}

	void ChipDnssdResolveNoLongerNeeded(const char * instanceName) {}

	CHIP_ERROR ChipDnssdReconfirmRecord(const char * hostname, chip::Inet::IPAddress address, chip::Inet::InterfaceId interface)
	{
	return CHIP_ERROR_NOT_IMPLEMENTED;
	}

	} // namespace Dnssd
	} // namespace chip