src/core/thread/network_data_service.hpp - third_party/openthread - Git at Google

 /*
  *  Copyright (c) 2021, The OpenThread Authors.
  *  All rights reserved.
  *
  *  Redistribution and use in source and binary forms, with or without
  *  modification, are permitted provided that the following conditions are met:
  *  1. Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  *  3. Neither the name of the copyright holder nor the
  *     names of its contributors may be used to endorse or promote products
  *     derived from this software without specific prior written permission.
  *
  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  *  POSSIBILITY OF SUCH DAMAGE.
  */

 /**
  * @file
  *   This file includes definitions related to Thread Network Data service/server entries.
  */

 #ifndef NETWORK_DATA_SERVICE_HPP_
 #define NETWORK_DATA_SERVICE_HPP_

 #include "openthread-core-config.h"

 #include <openthread/netdata.h>

 #include "backbone_router/bbr_leader.hpp"
 #include "common/encoding.hpp"
 #include "common/locator.hpp"
 #include "common/non_copyable.hpp"
 #include "common/serial_number.hpp"
 #include "net/socket.hpp"
 #include "thread/network_data_tlvs.hpp"

 namespace ot {
 namespace NetworkData {
 namespace Service {

 using ot::Encoding::BigEndian::HostSwap16;
 using ot::Encoding::BigEndian::HostSwap32;

 const uint32_t kThreadEnterpriseNumber = ServiceTlv::kThreadEnterpriseNumber; ///< Thread enterprise number.

 #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)

 /**
  * This type implements Thread Network Data "Backbone Router Service" server data generation and parsing.
  *
  */
 class BackboneRouter
 {
 public:
     /**
      * This constant variable represents the Backbone Router service data.
      *
      * The service data contains only the service number (THREAD_SERVICE_DATA_BBR) as a single byte.
      *
      */
     static const uint8_t     kServiceData        = 0x01;
     static constexpr uint8_t kServiceDataMinSize = 1;

     /**
      * This class implements the generation and parsing of "Backbone Router Service" server data.
      *
      */
     OT_TOOL_PACKED_BEGIN
     class ServerData
     {
     public:
         /**
          * This method returns the length (in bytes) of server data.
          *
          * @returns The server data length in bytes.
          *
          */
         uint8_t GetLength(void) const { return sizeof(ServerData); }

         /**
          * This method returns the sequence number of Backbone Router.
          *
          * @returns  The sequence number of the Backbone Router.
          *
          */
         uint8_t GetSequenceNumber(void) const { return mSequenceNumber; }

         /**
          * This method sets the sequence number of Backbone Router.
          *
          * @param[in]  aSequenceNumber  The sequence number of Backbone Router.
          *
          */
         void SetSequenceNumber(uint8_t aSequenceNumber) { mSequenceNumber = aSequenceNumber; }

         /**
          * This method returns the Registration Delay (in seconds) of Backbone Router.
          *
          * @returns The BBR Registration Delay (in seconds) of Backbone Router.
          *
          */
         uint16_t GetReregistrationDelay(void) const { return HostSwap16(mReregistrationDelay); }

         /**
          * This method sets the Registration Delay (in seconds) of Backbone Router.
          *
          * @param[in]  aReregistrationDelay  The Registration Delay (in seconds) of Backbone Router.
          *
          */
         void SetReregistrationDelay(uint16_t aReregistrationDelay)
         {
             mReregistrationDelay = HostSwap16(aReregistrationDelay);
         }

         /**
          * This method returns the multicast listener report timeout (in seconds) of Backbone Router.
          *
          * @returns The multicast listener report timeout (in seconds) of Backbone Router.
          *
          */
         uint32_t GetMlrTimeout(void) const { return HostSwap32(mMlrTimeout); }

         /**
          * This method sets multicast listener report timeout (in seconds) of Backbone Router.
          *
          * @param[in]  aMlrTimeout  The multicast listener report timeout (in seconds) of Backbone Router.
          *
          */
         void SetMlrTimeout(uint32_t aMlrTimeout) { mMlrTimeout = HostSwap32(aMlrTimeout); }

     private:
         uint8_t  mSequenceNumber;
         uint16_t mReregistrationDelay;
         uint32_t mMlrTimeout;
     } OT_TOOL_PACKED_END;

     BackboneRouter(void) = delete;
 };

 #endif // #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)

 /**
  * This type implements Thread Network Data "DNS/SRP Service Anycast Address" generation and parsing.
  *
  */
 class DnsSrpAnycast
 {
 public:
     static constexpr uint8_t kServiceNumber = 0x5c; ///< The service number of a `DnsSrpAnycast` entry.

     /**
      * This constant variable represents the short version of service data.
      *
      * The short version of service data contains only service number as a single byte.
      *
      */
     static const uint8_t kServiceData = kServiceNumber;

     /**
      * This structure represents information about an DNS/SRP server parsed from related Network Data service entries.
      *
      */
     struct Info
     {
         Ip6::Address mAnycastAddress; ///< The anycast address associated with the DNS/SRP servers.
         uint8_t      mSequenceNumber; ///< Sequence number used to notify SRP client if they need to re-register.
     };

     /**
      * This class represents the "DNS/SRP Service (Anycast)" service data.
      *
      */
     OT_TOOL_PACKED_BEGIN
     class ServiceData
     {
     public:
         /**
          * This constructor initializes the `ServiceData` object.
          *
          * @param[in] aSequenceNumber   The sequence number of "DNS/SRP server" service.
          *
          */
         explicit ServiceData(uint8_t aSequenceNumber)
             : mServiceNumber(kServiceNumber)
             , mSequenceNumber(aSequenceNumber)
         {
             OT_UNUSED_VARIABLE(mServiceNumber);
         }

         /**
          * This method returns the length (in bytes) of service data.
          *
          * @returns The data length in bytes.
          *
          */
         uint8_t GetLength(void) const { return sizeof(ServiceData); }

         /**
          * This method returns the sequence number.
          *
          * @returns The sequence number.
          *
          */
         uint8_t GetSequenceNumber(void) const { return mSequenceNumber; }

     private:
         uint8_t mServiceNumber;
         uint8_t mSequenceNumber;
     } OT_TOOL_PACKED_END;

     DnsSrpAnycast(void) = delete;
 };

 /**
  * This type implements Thread Network Data DNS/SRP Service (Unicast Address) generation and parsing.
  *
  */
 class DnsSrpUnicast
 {
 public:
     static constexpr uint8_t kServiceNumber = 0x5d; ///< The service number of `DnsSrpUnicast` entry.

     /**
      * This constant variable represents the short version of service data.
      *
      * The short version of service data contains only service number as a single byte.
      *
      */
     static const uint8_t kServiceData = kServiceNumber;

     /**
      * This enumeration represents the origin a `DnsSrpUnicast` entry.
      *
      */
     enum Origin : uint8_t
     {
         kFromServiceData, ///< Socket address is from service data.
         kFromServerData,  ///< Socket address is from server data.
     };

     /**
      * This structure represents information about an DNS/SRP server parsed from related Network Data service entries.
      *
      */
     struct Info
     {
         Ip6::SockAddr mSockAddr; ///< The socket address (IPv6 address and port) of the DNS/SRP server.
         Origin        mOrigin;   ///< The origin of the socket address (whether from service or server data).
     };

     /**
      * This class represents long version of "DNS/SRP Service (Unicast)" service data.
      *
      */
     OT_TOOL_PACKED_BEGIN
     class ServiceData
     {
     public:
         /**
          * This constructor initializes the `ServiceData` object.
          *
          * @param[in] aAddress   The IPv6 address of DNS/SRP server.
          * @param[in] aPort      The port number of DNS/SRP server.
          *
          */
         explicit ServiceData(const Ip6::Address &aAddress, uint16_t aPort)
             : mServiceNumber(kServiceNumber)
             , mAddress(aAddress)
             , mPort(HostSwap16(aPort))
         {
             OT_UNUSED_VARIABLE(mServiceNumber);
         }

         /**
          * This method returns the length (in bytes) of service data.
          *
          * @returns The data length in bytes.
          *
          */
         uint8_t GetLength(void) const { return sizeof(ServiceData); }

         /**
          * This method returns the IPv6 address.
          *
          * @returns The IPv6 address
          *
          */
         const Ip6::Address &GetAddress(void) const { return mAddress; }

         /**
          * This method returns the port number.
          *
          * @returns The port number.
          *
          */
         uint16_t GetPort(void) const { return HostSwap16(mPort); }

     private:
         uint8_t      mServiceNumber;
         Ip6::Address mAddress;
         uint16_t     mPort;
     } OT_TOOL_PACKED_END;

     /**
      * This class represents long version of "DNS/SRP Service (Unicast)" server data.
      *
      */
     OT_TOOL_PACKED_BEGIN
     class ServerData
     {
     public:
         /**
          * This constructor initializes the `ServerData` object.
          *
          * @param[in] aAddress   The IPv6 address of DNS/SRP server.
          * @param[in] aPort      The port number of DNS/SRP server.
          *
          */
         ServerData(const Ip6::Address &aAddress, uint16_t aPort)
             : mAddress(aAddress)
             , mPort(HostSwap16(aPort))
         {
         }

         /**
          * This method returns the length (in bytes) of server data.
          *
          * @returns The data length in bytes.
          *
          */
         uint8_t GetLength(void) const { return sizeof(ServerData); }

         /**
          * This method returns the IPv6 address.
          *
          * @returns The IPv6 address
          *
          */
         const Ip6::Address &GetAddress(void) const { return mAddress; }

         /**
          * This method returns the port number.
          *
          * @returns The port number.
          *
          */
         uint16_t GetPort(void) const { return HostSwap16(mPort); }

     private:
         Ip6::Address mAddress;
         uint16_t     mPort;
     } OT_TOOL_PACKED_END;

     DnsSrpUnicast(void) = delete;
 };

 /**
  * This class manages the Thread Service entries in Thread Network Data.
  *
  */
 class Manager : public InstanceLocator, private NonCopyable
 {
 public:
     /**
      * This class represents an iterator used to iterate through Network Data Service entries.
      *
      */
     class Iterator : public Clearable<Iterator>
     {
         friend class Manager;

     public:
         /**
          * This constructor initializes the iterator (as empty/clear).
          *
          */
         Iterator(void)
             : mServiceTlv(nullptr)
             , mServerSubTlv(nullptr)
         {
         }

         /**
          * This method resets the iterator to start from beginning.
          *
          */
         void Reset(void)
         {
             mServiceTlv   = nullptr;
             mServerSubTlv = nullptr;
         }

     private:
         const ServiceTlv *mServiceTlv;
         const ServerTlv * mServerSubTlv;
     };

     /**
      * This constructor initializes the `Manager` object.
      *
      * @param[in]  aInstance     A reference to the OpenThread instance.
      *
      */
     explicit Manager(Instance &aInstance)
         : InstanceLocator(aInstance)
     {
     }

 #if OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE
     /**
      * This method adds a Thread Service entry to the local Thread Network Data.
      *
      * This version of `Add<SeviceType>()` is intended for use with a `ServiceType` that has a constant service data
      * format with a non-empty and potentially non-const server data format (provided as input parameter).
      *
      * The template type `ServiceType` has the following requirements:
      *   - It MUST have a constant variable `ServiceType::kServiceData` specifying the service data.
      *   - It MUST define nested type `ServiceType::ServerData` representing the server data (and its format).
      *   - The `ServiceType::ServerData` MUST provide `GetLength()` method returning the length of server data.
      *
      * @tparam    ServiceType    The service type to be added.
      *
      * @param[in] aServerData    The server data.
      * @param[in] aServerStable  The Stable flag value for Server TLV.
      *
      * @retval kErrorNone     Successfully added the Service entry.
      * @retval kErrorNoBufs   Insufficient space to add the Service entry.
      *
      */
     template <typename ServiceType>
     Error Add(const typename ServiceType::ServerData &aServerData, bool aServerStable = true)
     {
         return AddService(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData), aServerStable, &aServerData,
                           aServerData.GetLength());
     }

     /**
      * This method adds a Thread Service entry to the local Thread Network Data.
      *
      * This version of `Add<SeviceType>()` is intended for use with a `ServiceType` that has a non-const service data
      * format (provided as input parameter) with an empty server data.
      *
      * The template type `ServiceType` has the following requirements:
      *   - It MUST define nested type `ServiceType::ServiceData` representing the service data (and its format).
      *   - The `ServiceType::ServiceData` MUST provide `GetLength()` method returning the length of service data.
      *
      * @tparam    ServiceType    The service type to be added.
      *
      * @param[in] aServiceData   The service data.
      * @param[in] aServerStable  The Stable flag value for Server TLV.
      *
      * @retval kErrorNone     Successfully added the Service entry.
      * @retval kErrorNoBufs   Insufficient space to add the Service entry.
      *
      */
     template <typename ServiceType>
     Error Add(const typename ServiceType::ServiceData &aServiceData, bool aServerStable = true)
     {
         return AddService(&aServiceData, aServiceData.GetLength(), aServerStable, nullptr, 0);
     }

     /**
      * This method removes a Thread Service entry from the local Thread Network Data.
      *
      * This version of `Remove<SeviceType>()` is intended for use with a `ServiceType` that has a constant service data
      * format.
      *
      * The template type `ServiceType` has the following requirements:
      *   - It MUST have a constant variable `ServiceType::kServiceData` specifying the service data.
      *
      * @tparam   ServiceType       The service type to be removed.
      *
      * @retval kErrorNone       Successfully removed the Service entry.
      * @retval kErrorNotFound   Could not find the Service entry.
      *
      */
     template <typename ServiceType> Error Remove(void)
     {
         return RemoveService(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData));
     }

     /**
      * This method removes a Thread Service entry from the local Thread Network Data.
      *
      * This version of `Remove<SeviceType>()` is intended for use with a `ServiceType` that has a non-const service data
      * format (provided as input parameter).
      *
      * The template type `ServiceType` has the following requirements:
      *   - It MUST define nested type `ServiceType::ServiceData` representing the service data (and its format).
      *   - The `ServiceType::ServiceData` MUST provide `GetLength()` method returning the length of service data.
      *
      * @tparam   ServiceType       The service type to be removed.
      *
      * @param[in] aServiceData     The service data.
      *
      * @retval kErrorNone       Successfully removed the Service entry.
      * @retval kErrorNotFound   Could not find the Service entry.
      *
      */
     template <typename ServiceType> Error Remove(const typename ServiceType::ServiceData &aServiceData)
     {
         return RemoveService(&aServiceData, aServiceData.GetLength());
     }

 #endif // OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE

     /**
      * This method gets the Service ID for the specified service from Thread Network Data.
      *
      * The template type `ServiceType` has the following requirements:
      *   - It MUST have a constant `ServiceType::kServiceNumber` specifying the service number.
      *
      * @tparam     ServiceType     The service type to be added.
      *
      * @param[in]  aServerStable   The Stable flag value for Server TLV
      * @param[out] aServiceId      A reference where to put the Service ID.
      *
      * @retval kErrorNone       Successfully got the Service ID.
      * @retval kErrorNotFound   The specified service was not found.
      *
      */
     template <typename ServiceType> Error GetServiceId(bool aServerStable, uint8_t &aServiceId) const
     {
         return GetServiceId(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData), aServerStable, aServiceId);
     }

 #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
     /**
      * This method gets the Primary Backbone Router (PBBR) in the Thread Network Data.
      *
      * @param[out]  aConfig      The Primary Backbone Router configuration.
      *
      */
     void GetBackboneRouterPrimary(ot::BackboneRouter::BackboneRouterConfig &aConfig) const;
 #endif

     /**
      * This method gets the next DNS/SRP info from the Thread Network Data "DNS/SRP Service Anycast Address" entries.
      *
      * To get the first entry, @p aIterator should be cleared (e.g., a new instance of `Iterator` or calling `Clear()`
      * method).
      *
      * @param[in,out] aIterator    A reference to an iterator.
      * @param[out]    aInfo        A reference to `DnsSrpAnycast::Info` to return the info.
      *
      * @retval kErrorNone       Successfully got the next info. @p aInfo and @p aIterator are updated.
      * @retval kErrorNotFound   No more matching entries in the Network Data.
      *
      */
     Error GetNextDnsSrpAnycastInfo(Iterator &aIterator, DnsSrpAnycast::Info &aInfo) const;

     /**
      * This method finds the preferred DNS/SRP info among all the Thread Network Data "DNS/SRP Service Anycast Address"
      * entries.
      *
      * The preferred entry is determined based on the sequence number value where a larger value (in the sense
      * specified by Serial Number Arithmetic logic in RFC-1982) is considered more recent and therefore preferred.
      *
      * @param[out] aInfo        A reference to `DnsSrpAnycast::Info` to return the info.
      *
      * @retval kErrorNone       Successfully found the preferred info. @p aInfo is updated.
      * @retval kErrorNotFound   No "DNS/SRP Service Anycast" entry in Network Data.
      *
      */
     Error FindPreferredDnsSrpAnycastInfo(DnsSrpAnycast::Info &aInfo) const;

     /**
      * This method gets the next DNS/SRP info from the Thread Network Data "DNS/SRP Service Unicast Address" entries.
      *
      * To get the first entry @p aIterator should be cleared (e.g., a new instance of `Iterator` or calling `Clear()`
      * method).
      *
      * @param[in,out] aIterator    A reference to an iterator.
      * @param[out]    aInfo        A reference to `DnsSrpUnicast::Info` to return the info.
      *
      * @retval kErrorNone       Successfully got the next info. @p aInfo and @p aIterator are updated.
      * @retval kErrorNotFound   No more matching entries in the Network Data.
      *
      */
     Error GetNextDnsSrpUnicastInfo(Iterator &aIterator, DnsSrpUnicast::Info &aInfo) const;

 private:
 #if OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE
     Error AddService(const void *aServiceData,
                      uint8_t     aServiceDataLength,
                      bool        aServerStable,
                      const void *aServerData,
                      uint8_t     aServerDataLength);
     Error RemoveService(const void *aServiceData, uint8_t aServiceDataLength);
 #endif

     Error GetServiceId(const void *aServiceData,
                        uint8_t     aServiceDataLength,
                        bool        aServerStable,
                        uint8_t &   aServiceId) const;
     Error IterateToNextServer(Iterator &aIterator) const;

 #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
     bool IsBackboneRouterPreferredTo(const ServerTlv &                 aServerTlv,
                                      const BackboneRouter::ServerData &aServerData,
                                      const ServerTlv &                 aOtherServerTlv,
                                      const BackboneRouter::ServerData &aOtherServerData) const;
 #endif
 };

 } // namespace Service
 } // namespace NetworkData
 } // namespace ot

 #endif // NETWORK_DATA_SERVICE_HPP_
	/*
	* Copyright (c) 2021, The OpenThread Authors.
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of the copyright holder nor the
	* names of its contributors may be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	* POSSIBILITY OF SUCH DAMAGE.
	*/

	/**
	* @file
	* This file includes definitions related to Thread Network Data service/server entries.
	*/

	#ifndef NETWORK_DATA_SERVICE_HPP_
	#define NETWORK_DATA_SERVICE_HPP_

	#include "openthread-core-config.h"

	#include <openthread/netdata.h>

	#include "backbone_router/bbr_leader.hpp"
	#include "common/encoding.hpp"
	#include "common/locator.hpp"
	#include "common/non_copyable.hpp"
	#include "common/serial_number.hpp"
	#include "net/socket.hpp"
	#include "thread/network_data_tlvs.hpp"

	namespace ot {
	namespace NetworkData {
	namespace Service {

	using ot::Encoding::BigEndian::HostSwap16;
	using ot::Encoding::BigEndian::HostSwap32;

	const uint32_t kThreadEnterpriseNumber = ServiceTlv::kThreadEnterpriseNumber; ///< Thread enterprise number.

	#if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)

	/**
	* This type implements Thread Network Data "Backbone Router Service" server data generation and parsing.
	*
	*/
	class BackboneRouter
	{
	public:
	/**
	* This constant variable represents the Backbone Router service data.
	*
	* The service data contains only the service number (THREAD_SERVICE_DATA_BBR) as a single byte.
	*
	*/
	static const uint8_t kServiceData = 0x01;
	static constexpr uint8_t kServiceDataMinSize = 1;

	/**
	* This class implements the generation and parsing of "Backbone Router Service" server data.
	*
	*/
	OT_TOOL_PACKED_BEGIN
	class ServerData
	{
	public:
	/**
	* This method returns the length (in bytes) of server data.
	*
	* @returns The server data length in bytes.
	*
	*/
	uint8_t GetLength(void) const { return sizeof(ServerData); }

	/**
	* This method returns the sequence number of Backbone Router.
	*
	* @returns The sequence number of the Backbone Router.
	*
	*/
	uint8_t GetSequenceNumber(void) const { return mSequenceNumber; }

	/**
	* This method sets the sequence number of Backbone Router.
	*
	* @param[in] aSequenceNumber The sequence number of Backbone Router.
	*
	*/
	void SetSequenceNumber(uint8_t aSequenceNumber) { mSequenceNumber = aSequenceNumber; }

	/**
	* This method returns the Registration Delay (in seconds) of Backbone Router.
	*
	* @returns The BBR Registration Delay (in seconds) of Backbone Router.
	*
	*/
	uint16_t GetReregistrationDelay(void) const { return HostSwap16(mReregistrationDelay); }

	/**
	* This method sets the Registration Delay (in seconds) of Backbone Router.
	*
	* @param[in] aReregistrationDelay The Registration Delay (in seconds) of Backbone Router.
	*
	*/
	void SetReregistrationDelay(uint16_t aReregistrationDelay)
	{
	mReregistrationDelay = HostSwap16(aReregistrationDelay);
	}

	/**
	* This method returns the multicast listener report timeout (in seconds) of Backbone Router.
	*
	* @returns The multicast listener report timeout (in seconds) of Backbone Router.
	*
	*/
	uint32_t GetMlrTimeout(void) const { return HostSwap32(mMlrTimeout); }

	/**
	* This method sets multicast listener report timeout (in seconds) of Backbone Router.
	*
	* @param[in] aMlrTimeout The multicast listener report timeout (in seconds) of Backbone Router.
	*
	*/
	void SetMlrTimeout(uint32_t aMlrTimeout) { mMlrTimeout = HostSwap32(aMlrTimeout); }

	private:
	uint8_t mSequenceNumber;
	uint16_t mReregistrationDelay;
	uint32_t mMlrTimeout;
	} OT_TOOL_PACKED_END;

	BackboneRouter(void) = delete;
	};

	#endif // #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)

	/**
	* This type implements Thread Network Data "DNS/SRP Service Anycast Address" generation and parsing.
	*
	*/
	class DnsSrpAnycast
	{
	public:
	static constexpr uint8_t kServiceNumber = 0x5c; ///< The service number of a `DnsSrpAnycast` entry.

	/**
	* This constant variable represents the short version of service data.
	*
	* The short version of service data contains only service number as a single byte.
	*
	*/
	static const uint8_t kServiceData = kServiceNumber;

	/**
	* This structure represents information about an DNS/SRP server parsed from related Network Data service entries.
	*
	*/
	struct Info
	{
	Ip6::Address mAnycastAddress; ///< The anycast address associated with the DNS/SRP servers.
	uint8_t mSequenceNumber; ///< Sequence number used to notify SRP client if they need to re-register.
	};

	/**
	* This class represents the "DNS/SRP Service (Anycast)" service data.
	*
	*/
	OT_TOOL_PACKED_BEGIN
	class ServiceData
	{
	public:
	/**
	* This constructor initializes the `ServiceData` object.
	*
	* @param[in] aSequenceNumber The sequence number of "DNS/SRP server" service.
	*
	*/
	explicit ServiceData(uint8_t aSequenceNumber)
	: mServiceNumber(kServiceNumber)
	, mSequenceNumber(aSequenceNumber)
	{
	OT_UNUSED_VARIABLE(mServiceNumber);
	}

	/**
	* This method returns the length (in bytes) of service data.
	*
	* @returns The data length in bytes.
	*
	*/
	uint8_t GetLength(void) const { return sizeof(ServiceData); }

	/**
	* This method returns the sequence number.
	*
	* @returns The sequence number.
	*
	*/
	uint8_t GetSequenceNumber(void) const { return mSequenceNumber; }

	private:
	uint8_t mServiceNumber;
	uint8_t mSequenceNumber;
	} OT_TOOL_PACKED_END;

	DnsSrpAnycast(void) = delete;
	};

	/**
	* This type implements Thread Network Data DNS/SRP Service (Unicast Address) generation and parsing.
	*
	*/
	class DnsSrpUnicast
	{
	public:
	static constexpr uint8_t kServiceNumber = 0x5d; ///< The service number of `DnsSrpUnicast` entry.

	/**
	* This constant variable represents the short version of service data.
	*
	* The short version of service data contains only service number as a single byte.
	*
	*/
	static const uint8_t kServiceData = kServiceNumber;

	/**
	* This enumeration represents the origin a `DnsSrpUnicast` entry.
	*
	*/
	enum Origin : uint8_t
	{
	kFromServiceData, ///< Socket address is from service data.
	kFromServerData, ///< Socket address is from server data.
	};

	/**
	* This structure represents information about an DNS/SRP server parsed from related Network Data service entries.
	*
	*/
	struct Info
	{
	Ip6::SockAddr mSockAddr; ///< The socket address (IPv6 address and port) of the DNS/SRP server.
	Origin mOrigin; ///< The origin of the socket address (whether from service or server data).
	};

	/**
	* This class represents long version of "DNS/SRP Service (Unicast)" service data.
	*
	*/
	OT_TOOL_PACKED_BEGIN
	class ServiceData
	{
	public:
	/**
	* This constructor initializes the `ServiceData` object.
	*
	* @param[in] aAddress The IPv6 address of DNS/SRP server.
	* @param[in] aPort The port number of DNS/SRP server.
	*
	*/
	explicit ServiceData(const Ip6::Address &aAddress, uint16_t aPort)
	: mServiceNumber(kServiceNumber)
	, mAddress(aAddress)
	, mPort(HostSwap16(aPort))
	{
	OT_UNUSED_VARIABLE(mServiceNumber);
	}

	/**
	* This method returns the length (in bytes) of service data.
	*
	* @returns The data length in bytes.
	*
	*/
	uint8_t GetLength(void) const { return sizeof(ServiceData); }

	/**
	* This method returns the IPv6 address.
	*
	* @returns The IPv6 address
	*
	*/
	const Ip6::Address &GetAddress(void) const { return mAddress; }

	/**
	* This method returns the port number.
	*
	* @returns The port number.
	*
	*/
	uint16_t GetPort(void) const { return HostSwap16(mPort); }

	private:
	uint8_t mServiceNumber;
	Ip6::Address mAddress;
	uint16_t mPort;
	} OT_TOOL_PACKED_END;

	/**
	* This class represents long version of "DNS/SRP Service (Unicast)" server data.
	*
	*/
	OT_TOOL_PACKED_BEGIN
	class ServerData
	{
	public:
	/**
	* This constructor initializes the `ServerData` object.
	*
	* @param[in] aAddress The IPv6 address of DNS/SRP server.
	* @param[in] aPort The port number of DNS/SRP server.
	*
	*/
	ServerData(const Ip6::Address &aAddress, uint16_t aPort)
	: mAddress(aAddress)
	, mPort(HostSwap16(aPort))
	{
	}

	/**
	* This method returns the length (in bytes) of server data.
	*
	* @returns The data length in bytes.
	*
	*/
	uint8_t GetLength(void) const { return sizeof(ServerData); }

	/**
	* This method returns the IPv6 address.
	*
	* @returns The IPv6 address
	*
	*/
	const Ip6::Address &GetAddress(void) const { return mAddress; }

	/**
	* This method returns the port number.
	*
	* @returns The port number.
	*
	*/
	uint16_t GetPort(void) const { return HostSwap16(mPort); }

	private:
	Ip6::Address mAddress;
	uint16_t mPort;
	} OT_TOOL_PACKED_END;

	DnsSrpUnicast(void) = delete;
	};

	/**
	* This class manages the Thread Service entries in Thread Network Data.
	*
	*/
	class Manager : public InstanceLocator, private NonCopyable
	{
	public:
	/**
	* This class represents an iterator used to iterate through Network Data Service entries.
	*
	*/
	class Iterator : public Clearable<Iterator>
	{
	friend class Manager;

	public:
	/**
	* This constructor initializes the iterator (as empty/clear).
	*
	*/
	Iterator(void)
	: mServiceTlv(nullptr)
	, mServerSubTlv(nullptr)
	{
	}

	/**
	* This method resets the iterator to start from beginning.
	*
	*/
	void Reset(void)
	{
	mServiceTlv = nullptr;
	mServerSubTlv = nullptr;
	}

	private:
	const ServiceTlv *mServiceTlv;
	const ServerTlv * mServerSubTlv;
	};

	/**
	* This constructor initializes the `Manager` object.
	*
	* @param[in] aInstance A reference to the OpenThread instance.
	*
	*/
	explicit Manager(Instance &aInstance)
	: InstanceLocator(aInstance)
	{
	}

	#if OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE
	/**
	* This method adds a Thread Service entry to the local Thread Network Data.
	*
	* This version of `Add<SeviceType>()` is intended for use with a `ServiceType` that has a constant service data
	* format with a non-empty and potentially non-const server data format (provided as input parameter).
	*
	* The template type `ServiceType` has the following requirements:
	* - It MUST have a constant variable `ServiceType::kServiceData` specifying the service data.
	* - It MUST define nested type `ServiceType::ServerData` representing the server data (and its format).
	* - The `ServiceType::ServerData` MUST provide `GetLength()` method returning the length of server data.
	*
	* @tparam ServiceType The service type to be added.
	*
	* @param[in] aServerData The server data.
	* @param[in] aServerStable The Stable flag value for Server TLV.
	*
	* @retval kErrorNone Successfully added the Service entry.
	* @retval kErrorNoBufs Insufficient space to add the Service entry.
	*
	*/
	template <typename ServiceType>
	Error Add(const typename ServiceType::ServerData &aServerData, bool aServerStable = true)
	{
	return AddService(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData), aServerStable, &aServerData,
	aServerData.GetLength());
	}

	/**
	* This method adds a Thread Service entry to the local Thread Network Data.
	*
	* This version of `Add<SeviceType>()` is intended for use with a `ServiceType` that has a non-const service data
	* format (provided as input parameter) with an empty server data.
	*
	* The template type `ServiceType` has the following requirements:
	* - It MUST define nested type `ServiceType::ServiceData` representing the service data (and its format).
	* - The `ServiceType::ServiceData` MUST provide `GetLength()` method returning the length of service data.
	*
	* @tparam ServiceType The service type to be added.
	*
	* @param[in] aServiceData The service data.
	* @param[in] aServerStable The Stable flag value for Server TLV.
	*
	* @retval kErrorNone Successfully added the Service entry.
	* @retval kErrorNoBufs Insufficient space to add the Service entry.
	*
	*/
	template <typename ServiceType>
	Error Add(const typename ServiceType::ServiceData &aServiceData, bool aServerStable = true)
	{
	return AddService(&aServiceData, aServiceData.GetLength(), aServerStable, nullptr, 0);
	}

	/**
	* This method removes a Thread Service entry from the local Thread Network Data.
	*
	* This version of `Remove<SeviceType>()` is intended for use with a `ServiceType` that has a constant service data
	* format.
	*
	* The template type `ServiceType` has the following requirements:
	* - It MUST have a constant variable `ServiceType::kServiceData` specifying the service data.
	*
	* @tparam ServiceType The service type to be removed.
	*
	* @retval kErrorNone Successfully removed the Service entry.
	* @retval kErrorNotFound Could not find the Service entry.
	*
	*/
	template <typename ServiceType> Error Remove(void)
	{
	return RemoveService(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData));
	}

	/**
	* This method removes a Thread Service entry from the local Thread Network Data.
	*
	* This version of `Remove<SeviceType>()` is intended for use with a `ServiceType` that has a non-const service data
	* format (provided as input parameter).
	*
	* The template type `ServiceType` has the following requirements:
	* - It MUST define nested type `ServiceType::ServiceData` representing the service data (and its format).
	* - The `ServiceType::ServiceData` MUST provide `GetLength()` method returning the length of service data.
	*
	* @tparam ServiceType The service type to be removed.
	*
	* @param[in] aServiceData The service data.
	*
	* @retval kErrorNone Successfully removed the Service entry.
	* @retval kErrorNotFound Could not find the Service entry.
	*
	*/
	template <typename ServiceType> Error Remove(const typename ServiceType::ServiceData &aServiceData)
	{
	return RemoveService(&aServiceData, aServiceData.GetLength());
	}

	#endif // OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE

	/**
	* This method gets the Service ID for the specified service from Thread Network Data.
	*
	* The template type `ServiceType` has the following requirements:
	* - It MUST have a constant `ServiceType::kServiceNumber` specifying the service number.
	*
	* @tparam ServiceType The service type to be added.
	*
	* @param[in] aServerStable The Stable flag value for Server TLV
	* @param[out] aServiceId A reference where to put the Service ID.
	*
	* @retval kErrorNone Successfully got the Service ID.
	* @retval kErrorNotFound The specified service was not found.
	*
	*/
	template <typename ServiceType> Error GetServiceId(bool aServerStable, uint8_t &aServiceId) const
	{
	return GetServiceId(&ServiceType::kServiceData, sizeof(ServiceType::kServiceData), aServerStable, aServiceId);
	}

	#if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
	/**
	* This method gets the Primary Backbone Router (PBBR) in the Thread Network Data.
	*
	* @param[out] aConfig The Primary Backbone Router configuration.
	*
	*/
	void GetBackboneRouterPrimary(ot::BackboneRouter::BackboneRouterConfig &aConfig) const;
	#endif

	/**
	* This method gets the next DNS/SRP info from the Thread Network Data "DNS/SRP Service Anycast Address" entries.
	*
	* To get the first entry, @p aIterator should be cleared (e.g., a new instance of `Iterator` or calling `Clear()`
	* method).
	*
	* @param[in,out] aIterator A reference to an iterator.
	* @param[out] aInfo A reference to `DnsSrpAnycast::Info` to return the info.
	*
	* @retval kErrorNone Successfully got the next info. @p aInfo and @p aIterator are updated.
	* @retval kErrorNotFound No more matching entries in the Network Data.
	*
	*/
	Error GetNextDnsSrpAnycastInfo(Iterator &aIterator, DnsSrpAnycast::Info &aInfo) const;

	/**
	* This method finds the preferred DNS/SRP info among all the Thread Network Data "DNS/SRP Service Anycast Address"
	* entries.
	*
	* The preferred entry is determined based on the sequence number value where a larger value (in the sense
	* specified by Serial Number Arithmetic logic in RFC-1982) is considered more recent and therefore preferred.
	*
	* @param[out] aInfo A reference to `DnsSrpAnycast::Info` to return the info.
	*
	* @retval kErrorNone Successfully found the preferred info. @p aInfo is updated.
	* @retval kErrorNotFound No "DNS/SRP Service Anycast" entry in Network Data.
	*
	*/
	Error FindPreferredDnsSrpAnycastInfo(DnsSrpAnycast::Info &aInfo) const;

	/**
	* This method gets the next DNS/SRP info from the Thread Network Data "DNS/SRP Service Unicast Address" entries.
	*
	* To get the first entry @p aIterator should be cleared (e.g., a new instance of `Iterator` or calling `Clear()`
	* method).
	*
	* @param[in,out] aIterator A reference to an iterator.
	* @param[out] aInfo A reference to `DnsSrpUnicast::Info` to return the info.
	*
	* @retval kErrorNone Successfully got the next info. @p aInfo and @p aIterator are updated.
	* @retval kErrorNotFound No more matching entries in the Network Data.
	*
	*/
	Error GetNextDnsSrpUnicastInfo(Iterator &aIterator, DnsSrpUnicast::Info &aInfo) const;

	private:
	#if OPENTHREAD_CONFIG_TMF_NETDATA_SERVICE_ENABLE
	Error AddService(const void *aServiceData,
	uint8_t aServiceDataLength,
	bool aServerStable,
	const void *aServerData,
	uint8_t aServerDataLength);
	Error RemoveService(const void *aServiceData, uint8_t aServiceDataLength);
	#endif

	Error GetServiceId(const void *aServiceData,
	uint8_t aServiceDataLength,
	bool aServerStable,
	uint8_t & aServiceId) const;
	Error IterateToNextServer(Iterator &aIterator) const;

	#if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
	bool IsBackboneRouterPreferredTo(const ServerTlv & aServerTlv,
	const BackboneRouter::ServerData &aServerData,
	const ServerTlv & aOtherServerTlv,
	const BackboneRouter::ServerData &aOtherServerData) const;
	#endif
	};

	} // namespace Service
	} // namespace NetworkData
	} // namespace ot

	#endif // NETWORK_DATA_SERVICE_HPP_