[build] refactor ot-br-agent (#1025)

Added library otbr-border-agent and otbr-sdp-proxy. Functionality of
ot-br-posix remains unchanged.

13 files changed, 8 insertions, 2800 deletions

diff --git a/src/agent/CMakeLists.txt b/src/agent/CMakeLists.txt
index 68099a3f..ebe02011 100644
--- a/src/agent/CMakeLists.txt
+++ b/src/agent/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-#  Copyright (c) 2020, The OpenThread Authors.
+#  Copyright (c) 2020-2021, The OpenThread Authors.
 #  All rights reserved.
 #
 #  Redistribution and use in source and binary forms, with or without
@@ -27,20 +27,10 @@
 #
 
 add_executable(otbr-agent
-    advertising_proxy.cpp
-    advertising_proxy.hpp
     agent_instance.cpp
     agent_instance.hpp
-    border_agent.cpp
-    border_agent.hpp
-    discovery_proxy.cpp
-    discovery_proxy.hpp
     main.cpp
     uris.hpp
-    ncp_openthread.cpp
-    ncp_openthread.hpp
-    thread_helper.cpp
-    thread_helper.hpp
     instance_params.cpp
     instance_params.hpp
 )
@@ -54,14 +44,16 @@ target_link_libraries(otbr-agent PRIVATE
     openthread-posix
     openthread-cli-ftd
     openthread-ftd
-    openthread-posix
     openthread-spinel-rcp
     openthread-hdlc
+    otbr-border-agent
+    otbr-sdp-proxy
+    otbr-ncp
     otbr-common
     otbr-utils
 )
 
-add_dependencies(otbr-agent ot-ctl print-ot-config)
+add_dependencies(otbr-agent ot-ctl print-ot-config otbr-border-agent otbr-sdp-proxy otbr-utils otbr-ncp)
 install(TARGETS otbr-agent DESTINATION sbin)
 
 if(CMAKE_VERSION VERSION_LESS 3.13)
diff --git a/src/agent/advertising_proxy.cpp b/src/agent/advertising_proxy.cpp
deleted file mode 100644
index ab3881cb..00000000
--- a/src/agent/advertising_proxy.cpp
+++ /dev/null
@@ -1,415 +0,0 @@
-/*
- *    Copyright (c) 2020, 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
- *   The file implements the Advertising Proxy.
- */
-
-#define OTBR_LOG_TAG "ADPROXY"
-
-#include "agent/advertising_proxy.hpp"
-
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-
-#if !OTBR_ENABLE_MDNS_AVAHI && !OTBR_ENABLE_MDNS_MDNSSD && !OTBR_ENABLE_MDNS_MOJO
-#error "The Advertising Proxy requires OTBR_ENABLE_MDNS_AVAHI, OTBR_ENABLE_MDNS_MDNSSD or OTBR_ENABLE_MDNS_MOJO"
-#endif
-
-#include <string>
-
-#include <assert.h>
-
-#include "common/code_utils.hpp"
-#include "common/dns_utils.hpp"
-#include "common/logging.hpp"
-
-namespace otbr {
-
-static otError OtbrErrorToOtError(otbrError aError)
-{
-    otError error;
-
-    switch (aError)
-    {
-    case OTBR_ERROR_NONE:
-        error = OT_ERROR_NONE;
-        break;
-
-    case OTBR_ERROR_NOT_FOUND:
-        error = OT_ERROR_NOT_FOUND;
-        break;
-
-    case OTBR_ERROR_PARSE:
-        error = OT_ERROR_PARSE;
-        break;
-
-    case OTBR_ERROR_NOT_IMPLEMENTED:
-        error = OT_ERROR_NOT_IMPLEMENTED;
-        break;
-
-    case OTBR_ERROR_INVALID_ARGS:
-        error = OT_ERROR_INVALID_ARGS;
-        break;
-
-    case OTBR_ERROR_DUPLICATED:
-        error = OT_ERROR_DUPLICATED;
-        break;
-
-    default:
-        error = OT_ERROR_FAILED;
-        break;
-    }
-
-    return error;
-}
-
-AdvertisingProxy::AdvertisingProxy(Ncp::ControllerOpenThread &aNcp, Mdns::Publisher &aPublisher)
-    : mNcp(aNcp)
-    , mPublisher(aPublisher)
-{
-}
-
-otbrError AdvertisingProxy::Start(void)
-{
-    otSrpServerSetServiceUpdateHandler(GetInstance(), AdvertisingHandler, this);
-
-    mPublisher.SetPublishServiceHandler(PublishServiceHandler, this);
-    mPublisher.SetPublishHostHandler(PublishHostHandler, this);
-
-    otbrLogInfo("Started");
-
-    return OTBR_ERROR_NONE;
-}
-
-void AdvertisingProxy::Stop()
-{
-    mPublisher.SetPublishServiceHandler(nullptr, nullptr);
-    mPublisher.SetPublishHostHandler(nullptr, nullptr);
-
-    // Outstanding updates will fail on the SRP server because of timeout.
-    // TODO: handle this case gracefully.
-
-    // Stop receiving SRP server events.
-    if (GetInstance() != nullptr)
-    {
-        otSrpServerSetServiceUpdateHandler(GetInstance(), nullptr, nullptr);
-    }
-
-    otbrLogInfo("Stopped");
-}
-
-void AdvertisingProxy::AdvertisingHandler(otSrpServerServiceUpdateId aId,
-                                          const otSrpServerHost *    aHost,
-                                          uint32_t                   aTimeout,
-                                          void *                     aContext)
-{
-    static_cast<AdvertisingProxy *>(aContext)->AdvertisingHandler(aId, aHost, aTimeout);
-}
-
-void AdvertisingProxy::AdvertisingHandler(otSrpServerServiceUpdateId aId,
-                                          const otSrpServerHost *    aHost,
-                                          uint32_t                   aTimeout)
-{
-    OTBR_UNUSED_VARIABLE(aTimeout);
-
-    OutstandingUpdate *update = nullptr;
-    otbrError          error  = OTBR_ERROR_NONE;
-
-    mOutstandingUpdates.emplace_back();
-    update      = &mOutstandingUpdates.back();
-    update->mId = aId;
-
-    error = PublishHostAndItsServices(aHost, update);
-
-    if (error != OTBR_ERROR_NONE || update->mCallbackCount == 0)
-    {
-        mOutstandingUpdates.pop_back();
-        otSrpServerHandleServiceUpdateResult(GetInstance(), aId, OtbrErrorToOtError(error));
-    }
-}
-
-void AdvertisingProxy::PublishServiceHandler(const char *aName, const char *aType, otbrError aError, void *aContext)
-{
-    std::string       name(aName);
-    std::string       type(aType);
-    AdvertisingProxy *thisPtr = static_cast<AdvertisingProxy *>(aContext);
-
-    thisPtr->mTaskRunner.Post(
-        [name, type, aError, thisPtr]() { thisPtr->PublishServiceHandler(name.c_str(), type.c_str(), aError); });
-}
-
-void AdvertisingProxy::PublishServiceHandler(const char *aName, const char *aType, otbrError aError)
-{
-    otbrError error = OTBR_ERROR_NONE;
-
-    otbrLogInfo("Handle publish service '%s.%s' result: %d", aName, aType, aError);
-
-    // TODO: there may be same names between two SRP updates.
-    for (auto update = mOutstandingUpdates.begin(); update != mOutstandingUpdates.end(); ++update)
-    {
-        for (auto nameAndType = update->mServiceNames.begin(); nameAndType != update->mServiceNames.end();
-             ++nameAndType)
-        {
-            if (aName != nameAndType->first || !Mdns::Publisher::IsServiceTypeEqual(aType, nameAndType->second.c_str()))
-            {
-                continue;
-            }
-
-            if (aError != OTBR_ERROR_NONE || update->mCallbackCount == 1)
-            {
-                otSrpServerServiceUpdateId updateId = update->mId;
-
-                // Erase before notifying OpenThread, because there are chances that new
-                // elements may be added to `otSrpServerHandleServiceUpdateResult` and
-                // the iterator will be invalidated.
-                mOutstandingUpdates.erase(update);
-                otSrpServerHandleServiceUpdateResult(GetInstance(), updateId, OtbrErrorToOtError(aError));
-            }
-            else
-            {
-                update->mServiceNames.erase(nameAndType);
-                --update->mCallbackCount;
-            }
-            ExitNow();
-        }
-    }
-
-exit:
-    if (error != OTBR_ERROR_NONE)
-    {
-        otbrLogWarning("Failed to handle result of service %s", aName);
-    }
-}
-
-void AdvertisingProxy::PublishHostHandler(const char *aName, otbrError aError, void *aContext)
-{
-    std::string       name(aName);
-    AdvertisingProxy *thisPtr = static_cast<AdvertisingProxy *>(aContext);
-
-    thisPtr->mTaskRunner.Post([name, aError, thisPtr]() { thisPtr->PublishHostHandler(name.c_str(), aError); });
-}
-
-void AdvertisingProxy::PublishHostHandler(const char *aName, otbrError aError)
-{
-    otbrError error = OTBR_ERROR_NONE;
-
-    otbrLogInfo("Handle publish host '%s' result: %d", aName, aError);
-
-    for (auto update = mOutstandingUpdates.begin(); update != mOutstandingUpdates.end(); ++update)
-    {
-        if (update->mHostNamePublished || aName != update->mHostName)
-        {
-            continue;
-        }
-
-        if (aError != OTBR_ERROR_NONE || update->mCallbackCount == 1)
-        {
-            otSrpServerServiceUpdateId updateId = update->mId;
-
-            // Erase before notifying OpenThread, because there are chances that new
-            // elements may be added to `otSrpServerHandleServiceUpdateResult` and
-            // the iterator will be invalidated.
-            mOutstandingUpdates.erase(update);
-            otSrpServerHandleServiceUpdateResult(GetInstance(), updateId, OtbrErrorToOtError(aError));
-        }
-        else
-        {
-            update->mHostNamePublished = true;
-            --update->mCallbackCount;
-        }
-        ExitNow();
-    }
-
-exit:
-    if (error != OTBR_ERROR_NONE)
-    {
-        otbrLogWarning("Failed to handle result of host %s", aName);
-    }
-}
-
-void AdvertisingProxy::PublishAllHostsAndServices(void)
-{
-    const otSrpServerHost *host = nullptr;
-
-    VerifyOrExit(mPublisher.IsStarted(), mPublisher.Start());
-
-    otbrLogInfo("Publish all hosts and services");
-    while ((host = otSrpServerGetNextHost(GetInstance(), host)))
-    {
-        PublishHostAndItsServices(host, nullptr);
-    }
-
-exit:
-    return;
-}
-
-void AdvertisingProxy::Update(MainloopContext &aMainloop)
-{
-    mTaskRunner.Update(aMainloop);
-}
-
-void AdvertisingProxy::Process(const MainloopContext &aMainloop)
-{
-    mTaskRunner.Process(aMainloop);
-}
-
-otbrError AdvertisingProxy::PublishHostAndItsServices(const otSrpServerHost *aHost, OutstandingUpdate *aUpdate)
-{
-    otbrError                 error = OTBR_ERROR_NONE;
-    const char *              fullHostName;
-    std::string               hostName;
-    std::string               hostDomain;
-    const otIp6Address *      hostAddress;
-    uint8_t                   hostAddressNum;
-    bool                      hostDeleted;
-    const otSrpServerService *service;
-
-    fullHostName = otSrpServerHostGetFullName(aHost);
-
-    otbrLogInfo("Advertise SRP service updates: host=%s", fullHostName);
-
-    SuccessOrExit(error = SplitFullHostName(fullHostName, hostName, hostDomain));
-    hostAddress = otSrpServerHostGetAddresses(aHost, &hostAddressNum);
-    hostDeleted = otSrpServerHostIsDeleted(aHost);
-
-    if (aUpdate)
-    {
-        aUpdate->mCallbackCount += !hostDeleted;
-        aUpdate->mHostName = hostName;
-        service            = nullptr;
-        while ((service = otSrpServerHostFindNextService(aHost, service, OT_SRP_SERVER_FLAGS_BASE_TYPE_SERVICE_ONLY,
-                                                         /* aServiceName */ nullptr, /* aInstanceName */ nullptr)))
-        {
-            aUpdate->mCallbackCount += !hostDeleted && !otSrpServerServiceIsDeleted(service);
-        }
-    }
-
-    if (!hostDeleted)
-    {
-        // TODO: select a preferred address or advertise all addresses from SRP client.
-        otbrLogInfo("Publish SRP host: %s", fullHostName);
-        SuccessOrExit(error =
-                          mPublisher.PublishHost(hostName.c_str(), hostAddress[0].mFields.m8, sizeof(hostAddress[0])));
-    }
-    else
-    {
-        otbrLogInfo("Unpublish SRP host: %s", fullHostName);
-        SuccessOrExit(error = mPublisher.UnpublishHost(hostName.c_str()));
-    }
-
-    service = nullptr;
-    while ((service = otSrpServerHostFindNextService(aHost, service, OT_SRP_SERVER_FLAGS_BASE_TYPE_SERVICE_ONLY,
-                                                     /* aServiceName */ nullptr, /* aInstanceName */ nullptr)))
-    {
-        const char *fullServiceName = otSrpServerServiceGetFullName(service);
-        std::string serviceName;
-        std::string serviceType;
-        std::string serviceDomain;
-
-        SuccessOrExit(error = SplitFullServiceInstanceName(fullServiceName, serviceName, serviceType, serviceDomain));
-
-        if (aUpdate)
-        {
-            aUpdate->mServiceNames.emplace_back(serviceName, serviceType);
-        }
-
-        if (!hostDeleted && !otSrpServerServiceIsDeleted(service))
-        {
-            Mdns::Publisher::TxtList     txtList     = MakeTxtList(service);
-            Mdns::Publisher::SubTypeList subTypeList = MakeSubTypeList(service);
-
-            otbrLogInfo("Publish SRP service: %s", fullServiceName);
-            SuccessOrExit(error = mPublisher.PublishService(hostName.c_str(), otSrpServerServiceGetPort(service),
-                                                            serviceName.c_str(), serviceType.c_str(), subTypeList,
-                                                            txtList));
-        }
-        else
-        {
-            otbrLogInfo("Unpublish SRP service: %s", fullServiceName);
-            SuccessOrExit(error = mPublisher.UnpublishService(serviceName.c_str(), serviceType.c_str()));
-        }
-    }
-
-exit:
-    if (error != OTBR_ERROR_NONE)
-    {
-        otbrLogInfo("Failed to advertise SRP service updates %p", aHost);
-    }
-    return error;
-}
-
-Mdns::Publisher::TxtList AdvertisingProxy::MakeTxtList(const otSrpServerService *aSrpService)
-{
-    const uint8_t *          txtData;
-    uint16_t                 txtDataLength = 0;
-    otDnsTxtEntryIterator    iterator;
-    otDnsTxtEntry            txtEntry;
-    Mdns::Publisher::TxtList txtList;
-
-    txtData = otSrpServerServiceGetTxtData(aSrpService, &txtDataLength);
-
-    otDnsInitTxtEntryIterator(&iterator, txtData, txtDataLength);
-
-    while (otDnsGetNextTxtEntry(&iterator, &txtEntry) == OT_ERROR_NONE)
-    {
-        txtList.emplace_back(txtEntry.mKey, txtEntry.mValue, txtEntry.mValueLength);
-    }
-
-    return txtList;
-}
-
-Mdns::Publisher::SubTypeList AdvertisingProxy::MakeSubTypeList(const otSrpServerService *aSrpService)
-{
-    const otSrpServerHost *      host         = otSrpServerServiceGetHost(aSrpService);
-    const char *                 instanceName = otSrpServerServiceGetInstanceName(aSrpService);
-    const otSrpServerService *   subService   = nullptr;
-    Mdns::Publisher::SubTypeList subTypeList;
-
-    while ((subService = otSrpServerHostFindNextService(
-                host, subService, (OT_SRP_SERVER_SERVICE_FLAG_SUB_TYPE | OT_SRP_SERVER_SERVICE_FLAG_ACTIVE),
-                /* aServiceName */ nullptr, instanceName)) != nullptr)
-    {
-        char subLabel[OT_DNS_MAX_LABEL_SIZE];
-
-        if (otSrpServerServiceGetServiceSubTypeLabel(subService, subLabel, sizeof(subLabel)) == OT_ERROR_NONE)
-        {
-            subTypeList.emplace_back(subLabel);
-        }
-        else
-        {
-            otbrLogWarning("Failed to retrieve subtype of SRP service: %s", otSrpServerServiceGetFullName(aSrpService));
-        }
-    }
-
-    return subTypeList;
-}
-
-} // namespace otbr
-
-#endif // OTBR_ENABLE_SRP_ADVERTISING_PROXY
diff --git a/src/agent/advertising_proxy.hpp b/src/agent/advertising_proxy.hpp
deleted file mode 100644
index 4d05782f..00000000
--- a/src/agent/advertising_proxy.hpp
+++ /dev/null
@@ -1,164 +0,0 @@
-/*
- *    Copyright (c) 2020, 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 for Advertising Proxy.
- */
-
-#ifndef OTBR_SRP_ADVERTISING_PROXY_HPP_
-#define OTBR_SRP_ADVERTISING_PROXY_HPP_
-
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-
-#include <stdint.h>
-
-#include <openthread/instance.h>
-#include <openthread/srp_server.h>
-
-#include "agent/ncp_openthread.hpp"
-#include "common/mainloop.hpp"
-#include "common/task_runner.hpp"
-#include "mdns/mdns.hpp"
-
-namespace otbr {
-
-/**
- * This class implements the Advertising Proxy.
- *
- */
-class AdvertisingProxy : public MainloopProcessor
-{
-public:
-    /**
-     * This constructor initializes the Advertising Proxy object.
-     *
-     * @param[in]  aNcp        A reference to the NCP controller.
-     * @param[in]  aPublisher  A reference to the mDNS publisher.
-     *
-     */
-    explicit AdvertisingProxy(Ncp::ControllerOpenThread &aNcp, Mdns::Publisher &aPublisher);
-
-    /**
-     * This method starts the Advertising Proxy.
-     *
-     * @retval  OTBR_ERROR_NONE  Successfully started the Advertising Proxy.
-     * @retval  ...              Failed to start the Advertising Proxy.
-     *
-     */
-    otbrError Start(void);
-
-    /**
-     * This method stops the Advertising Proxy.
-     *
-     */
-    void Stop();
-
-    /**
-     * This method publishes all registered hosts and services.
-     *
-     */
-    void PublishAllHostsAndServices(void);
-
-    /**
-     * This method updates the mainloop context.
-     *
-     * @param[inout]  aMainloop  A reference to the mainloop to be updated.
-     *
-     */
-    void Update(MainloopContext &aMainloop) override;
-
-    /**
-     * This method processes mainloop events.
-     *
-     * @param[in]  aMainloop  A reference to the mainloop context.
-     *
-     */
-    void Process(const MainloopContext &aMainloop) override;
-
-private:
-    struct OutstandingUpdate
-    {
-        typedef std::vector<std::pair<std::string, std::string>> ServiceNameList;
-
-        otSrpServerServiceUpdateId mId;                    // The ID of the SRP service update transaction.
-        std::string                mHostName;              // The host name.
-        ServiceNameList            mServiceNames;          // The list of service instance and name pairs to be updated.
-        uint32_t                   mCallbackCount     = 0; // The number of callbacks which we are waiting for.
-        bool                       mHostNamePublished = false; // Is the host name already published?
-    };
-
-    static void AdvertisingHandler(otSrpServerServiceUpdateId aId,
-                                   const otSrpServerHost *    aHost,
-                                   uint32_t                   aTimeout,
-                                   void *                     aContext);
-    void        AdvertisingHandler(otSrpServerServiceUpdateId aId, const otSrpServerHost *aHost, uint32_t aTimeout);
-
-    static Mdns::Publisher::TxtList     MakeTxtList(const otSrpServerService *aSrpService);
-    static Mdns::Publisher::SubTypeList MakeSubTypeList(const otSrpServerService *aSrpService);
-
-    static void PublishServiceHandler(const char *aName, const char *aType, otbrError aError, void *aContext);
-    void        PublishServiceHandler(const char *aName, const char *aType, otbrError aError);
-    static void PublishHostHandler(const char *aName, otbrError aError, void *aContext);
-    void        PublishHostHandler(const char *aName, otbrError aError);
-
-    /**
-     * This method publishes a specified host and its services.
-     *
-     * It also makes a OutstandingUpdate object when needed.
-     *
-     * @param[in]  aHost         A pointer to the host.
-     * @param[in]  aUpdate       A pointer to the output OutstandingUpdate object. When it's not null, the method will
-     *                           fill its fields, otherwise it's ignored.
-     *
-     * @retval  OTBR_ERROR_NONE  Successfully published the host and its services.
-     * @retval  ...              Failed to publish the host and/or its services.
-     *
-     */
-    otbrError PublishHostAndItsServices(const otSrpServerHost *aHost, OutstandingUpdate *aUpdate);
-
-    otInstance *GetInstance(void) { return mNcp.GetInstance(); }
-
-    // A reference to the NCP controller, has no ownership.
-    Ncp::ControllerOpenThread &mNcp;
-
-    // A reference to the mDNS publisher, has no ownership.
-    Mdns::Publisher &mPublisher;
-
-    // A vector that tracks outstanding updates.
-    std::vector<OutstandingUpdate> mOutstandingUpdates;
-
-    // Task runner for running tasks in the context of the main thread.
-    TaskRunner mTaskRunner;
-};
-
-} // namespace otbr
-
-#endif // OTBR_ENABLE_SRP_ADVERTISING_PROXY
-
-#endif // OTBR_SRP_ADVERTISING_PROXY_HPP_
diff --git a/src/agent/agent_instance.hpp b/src/agent/agent_instance.hpp
index 92d13dd7..b5c92cb6 100644
--- a/src/agent/agent_instance.hpp
+++ b/src/agent/agent_instance.hpp
@@ -41,10 +41,10 @@
 #include <sys/select.h>
 #include <sys/types.h>
 
-#include "agent/border_agent.hpp"
 #include "agent/instance_params.hpp"
-#include "agent/ncp_openthread.hpp"
+#include "border_agent/border_agent.hpp"
 #include "common/mainloop.hpp"
+#include "ncp/ncp_openthread.hpp"
 
 namespace otbr {
 
diff --git a/src/agent/border_agent.cpp b/src/agent/border_agent.cpp
deleted file mode 100644
index 638b2a8a..00000000
--- a/src/agent/border_agent.cpp
+++ /dev/null
@@ -1,400 +0,0 @@
-/*
- *    Copyright (c) 2017, 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
- *   The file implements the Thread border agent.
- */
-
-#define OTBR_LOG_TAG "AGENT"
-
-#include "agent/border_agent.hpp"
-
-#include <arpa/inet.h>
-#include <assert.h>
-#include <errno.h>
-#include <netinet/in.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <openthread/border_agent.h>
-#include <openthread/thread_ftd.h>
-#include <openthread/platform/toolchain.h>
-
-#include "agent/ncp_openthread.hpp"
-#include "agent/uris.hpp"
-#if OTBR_ENABLE_BACKBONE_ROUTER
-#include "backbone_router/backbone_agent.hpp"
-#endif
-#include "common/byteswap.hpp"
-#include "common/code_utils.hpp"
-#include "common/logging.hpp"
-#include "common/tlv.hpp"
-#include "common/types.hpp"
-#include "utils/hex.hpp"
-#include "utils/strcpy_utils.hpp"
-
-namespace otbr {
-
-static const char kBorderAgentServiceType[] = "_meshcop._udp"; ///< Border agent service type of mDNS
-static const char kBorderAgentServiceInstanceName[] =
-    OTBR_MESHCOP_SERVICE_INSTANCE_NAME; ///< Border agent service name of mDNS
-
-/**
- * Locators
- *
- */
-enum
-{
-    kAloc16Leader   = 0xfc00, ///< leader anycast locator.
-    kInvalidLocator = 0xffff, ///< invalid locator.
-};
-
-uint32_t BorderAgent::StateBitmap::ToUint32(void) const
-{
-    uint32_t bitmap = 0;
-
-    bitmap |= mConnectionMode << 0;
-    bitmap |= mThreadIfStatus << 3;
-    bitmap |= mAvailability << 5;
-    bitmap |= mBbrIsActive << 7;
-    bitmap |= mBbrIsPrimary << 8;
-
-    return bitmap;
-}
-
-BorderAgent::BorderAgent(otbr::Ncp::ControllerOpenThread &aNcp)
-    : mNcp(aNcp)
-#if OTBR_ENABLE_MDNS_AVAHI || OTBR_ENABLE_MDNS_MDNSSD || OTBR_ENABLE_MDNS_MOJO
-    , mPublisher(Mdns::Publisher::Create(AF_UNSPEC, /* aDomain */ nullptr, HandleMdnsState, this))
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    , mAdvertisingProxy(aNcp, *mPublisher)
-#endif
-#else
-    , mPublisher(nullptr)
-#endif
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-    , mDiscoveryProxy(aNcp, *mPublisher)
-#endif
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    , mBackboneAgent(aNcp)
-#endif
-{
-}
-
-void BorderAgent::Init(void)
-{
-    mNcp.AddThreadStateChangedCallback([this](otChangedFlags aFlags) { HandleThreadStateChanged(aFlags); });
-
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    mBackboneAgent.Init();
-#endif
-
-    if (IsThreadStarted())
-    {
-        Start();
-    }
-    else
-    {
-        Stop();
-    }
-}
-
-otbrError BorderAgent::Start(void)
-{
-    otbrError error = OTBR_ERROR_NONE;
-
-    VerifyOrExit(IsThreadStarted(), errno = EAGAIN, error = OTBR_ERROR_ERRNO);
-
-    // In case we didn't receive Thread down event.
-    Stop();
-
-#if OTBR_ENABLE_MDNS_AVAHI || OTBR_ENABLE_MDNS_MDNSSD || OTBR_ENABLE_MDNS_MOJO
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    mAdvertisingProxy.Start();
-#endif
-    UpdateMeshCopService();
-
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-    mDiscoveryProxy.Start();
-#endif
-
-#endif // OTBR_ENABLE_MDNS_AVAHI || OTBR_ENABLE_MDNS_MDNSSD || OTBR_ENABLE_MDNS_MOJO
-
-exit:
-    otbrLogResult(error, "Start Thread Border Agent");
-    return error;
-}
-
-void BorderAgent::Stop(void)
-{
-    otbrLogInfo("Stop Thread Border Agent");
-
-#if OTBR_ENABLE_MDNS_AVAHI || OTBR_ENABLE_MDNS_MDNSSD || OTBR_ENABLE_MDNS_MOJO
-    mPublisher->Stop();
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    mAdvertisingProxy.Stop();
-#endif
-
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-    mDiscoveryProxy.Stop();
-#endif
-
-#endif
-}
-
-void BorderAgent::HandleMdnsState(void *aContext, Mdns::Publisher::State aState)
-{
-    static_cast<BorderAgent *>(aContext)->HandleMdnsState(aState);
-}
-
-BorderAgent::~BorderAgent(void)
-{
-    Stop();
-
-    if (mPublisher != nullptr)
-    {
-        delete mPublisher;
-        mPublisher = nullptr;
-    }
-}
-
-void BorderAgent::HandleMdnsState(Mdns::Publisher::State aState)
-{
-    switch (aState)
-    {
-    case Mdns::Publisher::State::kReady:
-        UpdateMeshCopService();
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-        mAdvertisingProxy.PublishAllHostsAndServices();
-#endif
-        break;
-    default:
-        otbrLogWarning("mDNS service not available!");
-        break;
-    }
-}
-
-void BorderAgent::Update(MainloopContext &aMainloop)
-{
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    mBackboneAgent.Update(aMainloop);
-#endif
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    mAdvertisingProxy.Update(aMainloop);
-#endif
-
-    if (mPublisher != nullptr)
-    {
-        mPublisher->Update(aMainloop);
-    }
-}
-
-void BorderAgent::Process(const MainloopContext &aMainloop)
-{
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    mBackboneAgent.Process(aMainloop);
-#endif
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    mAdvertisingProxy.Process(aMainloop);
-#endif
-
-    if (mPublisher != nullptr)
-    {
-        mPublisher->Process(aMainloop);
-    }
-}
-
-void BorderAgent::PublishMeshCopService(void)
-{
-    StateBitmap              state;
-    uint32_t                 stateUint32;
-    otInstance *             instance    = mNcp.GetInstance();
-    const otExtendedPanId *  extPanId    = otThreadGetExtendedPanId(instance);
-    const otExtAddress *     extAddr     = otLinkGetExtendedAddress(instance);
-    const char *             networkName = otThreadGetNetworkName(instance);
-    Mdns::Publisher::TxtList txtList{{"rv", "1"}};
-
-    otbrLogInfo("Publish meshcop service %s.%s.local.", kBorderAgentServiceInstanceName, kBorderAgentServiceType);
-
-    txtList.emplace_back("nn", networkName);
-    txtList.emplace_back("xp", extPanId->m8, sizeof(extPanId->m8));
-    txtList.emplace_back("tv", mNcp.GetThreadVersion());
-
-    // "dd" represents for device discriminator which
-    // should always be the IEEE 802.15.4 extended address.
-    txtList.emplace_back("dd", extAddr->m8, sizeof(extAddr->m8));
-
-    state.mConnectionMode = kConnectionModePskc;
-    state.mAvailability   = kAvailabilityHigh;
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    state.mBbrIsActive  = otBackboneRouterGetState(instance) != OT_BACKBONE_ROUTER_STATE_DISABLED;
-    state.mBbrIsPrimary = otBackboneRouterGetState(instance) == OT_BACKBONE_ROUTER_STATE_PRIMARY;
-#endif
-    switch (otThreadGetDeviceRole(instance))
-    {
-    case OT_DEVICE_ROLE_DISABLED:
-        state.mThreadIfStatus = kThreadIfStatusNotInitialized;
-        break;
-    case OT_DEVICE_ROLE_DETACHED:
-        state.mThreadIfStatus = kThreadIfStatusInitialized;
-        break;
-    default:
-        state.mThreadIfStatus = kThreadIfStatusActive;
-    }
-
-    stateUint32 = htobe32(state.ToUint32());
-    txtList.emplace_back("sb", reinterpret_cast<uint8_t *>(&stateUint32), sizeof(stateUint32));
-
-    if (state.mThreadIfStatus == kThreadIfStatusActive)
-    {
-        otError              error;
-        otOperationalDataset activeDataset;
-        uint64_t             activeTimestamp;
-        uint32_t             partitionId;
-
-        if ((error = otDatasetGetActive(instance, &activeDataset)) != OT_ERROR_NONE)
-        {
-            otbrLogWarning("Failed to get active dataset: %s", otThreadErrorToString(error));
-        }
-        else
-        {
-            activeTimestamp = htobe64(activeDataset.mActiveTimestamp);
-            txtList.emplace_back("at", reinterpret_cast<uint8_t *>(&activeTimestamp), sizeof(activeTimestamp));
-        }
-
-        partitionId = otThreadGetPartitionId(instance);
-        txtList.emplace_back("pt", reinterpret_cast<uint8_t *>(&partitionId), sizeof(partitionId));
-    }
-
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    if (state.mBbrIsActive)
-    {
-        otBackboneRouterConfig bbrConfig;
-        uint16_t               bbrPort = htobe16(BackboneRouter::BackboneAgent::kBackboneUdpPort);
-
-        otBackboneRouterGetConfig(instance, &bbrConfig);
-        txtList.emplace_back("sq", &bbrConfig.mSequenceNumber, sizeof(bbrConfig.mSequenceNumber));
-        txtList.emplace_back("bb", reinterpret_cast<const uint8_t *>(&bbrPort), sizeof(bbrPort));
-    }
-
-    txtList.emplace_back("dn", otThreadGetDomainName(instance));
-#endif
-
-    mPublisher->PublishService(/* aHostName */ nullptr, otBorderAgentGetUdpPort(instance),
-                               kBorderAgentServiceInstanceName, kBorderAgentServiceType, Mdns::Publisher::SubTypeList{},
-                               txtList);
-}
-
-void BorderAgent::UnpublishMeshCopService(void)
-{
-    assert(IsThreadStarted());
-    VerifyOrExit(!mNetworkName.empty());
-
-    otbrLogInfo("Unpublish meshcop service %s.%s.local.", kBorderAgentServiceInstanceName, kBorderAgentServiceType);
-
-    mPublisher->UnpublishService(kBorderAgentServiceInstanceName, kBorderAgentServiceType);
-
-exit:
-    return;
-}
-
-void BorderAgent::UpdateMeshCopService(void)
-{
-    assert(IsThreadStarted());
-
-    const char *networkName = otThreadGetNetworkName(mNcp.GetInstance());
-
-    VerifyOrExit(mPublisher->IsStarted(), mPublisher->Start());
-    VerifyOrExit(IsPskcInitialized(), UnpublishMeshCopService());
-
-    PublishMeshCopService();
-    mNetworkName = networkName;
-
-exit:
-    return;
-}
-
-void BorderAgent::HandleThreadStateChanged(otChangedFlags aFlags)
-{
-    VerifyOrExit(mPublisher != nullptr);
-    VerifyOrExit(aFlags & (OT_CHANGED_THREAD_ROLE | OT_CHANGED_THREAD_EXT_PANID | OT_CHANGED_THREAD_NETWORK_NAME |
-                           OT_CHANGED_ACTIVE_DATASET | OT_CHANGED_THREAD_PARTITION_ID |
-                           OT_CHANGED_THREAD_BACKBONE_ROUTER_STATE | OT_CHANGED_PSKC));
-
-    if (aFlags & OT_CHANGED_THREAD_ROLE)
-    {
-        otbrLogInfo("Thread is %s", (IsThreadStarted() ? "up" : "down"));
-
-        if (IsThreadStarted())
-        {
-            Start();
-        }
-        else
-        {
-            Stop();
-        }
-    }
-    else if (IsThreadStarted())
-    {
-        UpdateMeshCopService();
-    }
-
-exit:
-    return;
-}
-
-bool BorderAgent::IsThreadStarted(void) const
-{
-    otDeviceRole role = otThreadGetDeviceRole(mNcp.GetInstance());
-
-    return role == OT_DEVICE_ROLE_CHILD || role == OT_DEVICE_ROLE_ROUTER || role == OT_DEVICE_ROLE_LEADER;
-}
-
-bool BorderAgent::IsPskcInitialized(void) const
-{
-    bool   initialized = false;
-    otPskc pskc;
-
-    otThreadGetPskc(mNcp.GetInstance(), &pskc);
-
-    for (uint8_t byte : pskc.m8)
-    {
-        if (byte != 0x00)
-        {
-            initialized = true;
-            break;
-        }
-    }
-
-    return initialized;
-}
-
-} // namespace otbr
diff --git a/src/agent/border_agent.hpp b/src/agent/border_agent.hpp
deleted file mode 100644
index 7fca894b..00000000
--- a/src/agent/border_agent.hpp
+++ /dev/null
@@ -1,191 +0,0 @@
-/*
- *    Copyright (c) 2017, 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 definition for Thread border agent.
- */
-
-#ifndef OTBR_AGENT_BORDER_AGENT_HPP_
-#define OTBR_AGENT_BORDER_AGENT_HPP_
-
-#include <vector>
-
-#include <stdint.h>
-
-#include "agent/advertising_proxy.hpp"
-#include "agent/discovery_proxy.hpp"
-#include "agent/instance_params.hpp"
-#include "agent/ncp_openthread.hpp"
-#include "common/mainloop.hpp"
-#include "mdns/mdns.hpp"
-
-#if OTBR_ENABLE_BACKBONE_ROUTER
-#include "backbone_router/backbone_agent.hpp"
-#endif
-
-#ifndef OTBR_VENDOR_NAME
-#define OTBR_VENDOR_NAME "OpenThread"
-#endif
-
-#ifndef OTBR_PRODUCT_NAME
-#define OTBR_PRODUCT_NAME "BorderRouter"
-#endif
-
-#ifndef OTBR_MESHCOP_SERVICE_INSTANCE_NAME
-#define OTBR_MESHCOP_SERVICE_INSTANCE_NAME OTBR_VENDOR_NAME "_" OTBR_PRODUCT_NAME
-#endif
-
-namespace otbr {
-
-/**
- * @addtogroup border-router-border-agent
- *
- * @brief
- *   This module includes definition for Thread border agent
- *
- * @{
- */
-
-/**
- * This class implements Thread border agent functionality.
- *
- */
-class BorderAgent : public MainloopProcessor
-{
-public:
-    /**
-     * The constructor to initialize the Thread border agent.
-     *
-     * @param[in]  aNcp  A reference to the NCP controller.
-     *
-     */
-    BorderAgent(otbr::Ncp::ControllerOpenThread &aNcp);
-
-    ~BorderAgent(void) override;
-
-    /**
-     * This method initialize border agent service.
-     *
-     */
-    void Init(void);
-
-    /**
-     * This method updates the mainloop context.
-     *
-     * @param[inout]  aMainloop  A reference to the mainloop to be updated.
-     *
-     */
-    void Update(MainloopContext &aMainloop) override;
-
-    /**
-     * This method processes mainloop events.
-     *
-     * @param[in]  aMainloop  A reference to the mainloop context.
-     *
-     */
-    void Process(const MainloopContext &aMainloop) override;
-
-private:
-    enum : uint8_t
-    {
-        kConnectionModeDisabled = 0,
-        kConnectionModePskc     = 1,
-        kConnectionModePskd     = 2,
-        kConnectionModeVendor   = 3,
-        kConnectionModeX509     = 4,
-    };
-
-    enum : uint8_t
-    {
-        kThreadIfStatusNotInitialized = 0,
-        kThreadIfStatusInitialized    = 1,
-        kThreadIfStatusActive         = 2,
-    };
-
-    enum : uint8_t
-    {
-        kAvailabilityInfrequent = 0,
-        kAvailabilityHigh       = 1,
-    };
-
-    struct StateBitmap
-    {
-        uint32_t mConnectionMode : 3;
-        uint32_t mThreadIfStatus : 2;
-        uint32_t mAvailability : 2;
-        uint32_t mBbrIsActive : 1;
-        uint32_t mBbrIsPrimary : 1;
-
-        StateBitmap(void)
-            : mConnectionMode(0)
-            , mThreadIfStatus(0)
-            , mAvailability(0)
-            , mBbrIsActive(0)
-            , mBbrIsPrimary(0)
-        {
-        }
-
-        uint32_t ToUint32(void) const;
-    };
-
-    otbrError   Start(void);
-    void        Stop(void);
-    static void HandleMdnsState(void *aContext, Mdns::Publisher::State aState);
-    void        HandleMdnsState(Mdns::Publisher::State aState);
-    void        PublishMeshCopService(void);
-    void        UnpublishMeshCopService(void);
-    void        UpdateMeshCopService(void);
-
-    void HandleThreadStateChanged(otChangedFlags aFlags);
-
-    bool IsThreadStarted(void) const;
-    bool IsPskcInitialized(void) const;
-
-    otbr::Ncp::ControllerOpenThread &mNcp;
-    Mdns::Publisher *                mPublisher;
-    std::string                      mNetworkName;
-
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    AdvertisingProxy mAdvertisingProxy;
-#endif
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-    Dnssd::DiscoveryProxy mDiscoveryProxy;
-#endif
-#if OTBR_ENABLE_BACKBONE_ROUTER
-    BackboneRouter::BackboneAgent mBackboneAgent;
-#endif
-};
-
-/**
- * @}
- */
-
-} // namespace otbr
-
-#endif // OTBR_AGENT_BORDER_AGENT_HPP_
diff --git a/src/agent/discovery_proxy.cpp b/src/agent/discovery_proxy.cpp
deleted file mode 100644
index 02f798a0..00000000
--- a/src/agent/discovery_proxy.cpp
+++ /dev/null
@@ -1,339 +0,0 @@
-/*
- *    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
- *   The file implements the DNS-SD Discovery Proxy.
- */
-
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-
-#define OTBR_LOG_TAG "DPROXY"
-
-#include "agent/discovery_proxy.hpp"
-
-#include <algorithm>
-#include <string>
-
-#include <assert.h>
-
-#include <openthread/dnssd_server.h>
-
-#include "common/code_utils.hpp"
-#include "common/dns_utils.hpp"
-#include "common/logging.hpp"
-
-namespace otbr {
-namespace Dnssd {
-
-DiscoveryProxy::DiscoveryProxy(Ncp::ControllerOpenThread &aNcp, Mdns::Publisher &aPublisher)
-    : mNcp(aNcp)
-    , mMdnsPublisher(aPublisher)
-{
-}
-
-void DiscoveryProxy::Start(void)
-{
-    otDnssdQuerySetCallbacks(mNcp.GetInstance(), &DiscoveryProxy::OnDiscoveryProxySubscribe,
-                             &DiscoveryProxy::OnDiscoveryProxyUnsubscribe, this);
-
-    mMdnsPublisher.SetSubscriptionCallbacks(
-        [this](const std::string &aType, const Mdns::Publisher::DiscoveredInstanceInfo &aInstanceInfo) {
-            OnServiceDiscovered(aType, aInstanceInfo);
-        },
-
-        [this](const std::string &aHostName, const Mdns::Publisher::DiscoveredHostInfo &aHostInfo) {
-            OnHostDiscovered(aHostName, aHostInfo);
-        });
-
-    otbrLogInfo("started");
-}
-
-void DiscoveryProxy::Stop(void)
-{
-    otDnssdQuerySetCallbacks(mNcp.GetInstance(), nullptr, nullptr, nullptr);
-    mMdnsPublisher.SetSubscriptionCallbacks(nullptr, nullptr);
-
-    otbrLogInfo("stopped");
-}
-
-void DiscoveryProxy::OnDiscoveryProxySubscribe(void *aContext, const char *aFullName)
-{
-    reinterpret_cast<DiscoveryProxy *>(aContext)->OnDiscoveryProxySubscribe(aFullName);
-}
-
-void DiscoveryProxy::OnDiscoveryProxySubscribe(const char *aFullName)
-{
-    std::string fullName(aFullName);
-    otbrError   error    = OTBR_ERROR_NONE;
-    DnsNameInfo nameInfo = SplitFullDnsName(fullName);
-
-    otbrLogInfo("subscribe: %s", fullName.c_str());
-
-    if (GetServiceSubscriptionCount(nameInfo) == 1)
-    {
-        if (nameInfo.mHostName.empty())
-        {
-            mMdnsPublisher.SubscribeService(nameInfo.mServiceName, nameInfo.mInstanceName);
-        }
-        else
-        {
-            mMdnsPublisher.SubscribeHost(nameInfo.mHostName);
-        }
-    }
-
-    if (error != OTBR_ERROR_NONE)
-    {
-        otbrLogWarning("failed to subscribe %s: %s", fullName.c_str(), otbrErrorString(error));
-    }
-}
-
-void DiscoveryProxy::OnDiscoveryProxyUnsubscribe(void *aContext, const char *aFullName)
-{
-    reinterpret_cast<DiscoveryProxy *>(aContext)->OnDiscoveryProxyUnsubscribe(aFullName);
-}
-
-void DiscoveryProxy::OnDiscoveryProxyUnsubscribe(const char *aFullName)
-{
-    std::string fullName(aFullName);
-    otbrError   error    = OTBR_ERROR_NONE;
-    DnsNameInfo nameInfo = SplitFullDnsName(fullName);
-
-    otbrLogInfo("unsubscribe: %s", fullName.c_str());
-
-    if (GetServiceSubscriptionCount(nameInfo) == 1)
-    {
-        if (nameInfo.mHostName.empty())
-        {
-            mMdnsPublisher.UnsubscribeService(nameInfo.mServiceName, nameInfo.mInstanceName);
-        }
-        else
-        {
-            mMdnsPublisher.UnsubscribeHost(nameInfo.mHostName);
-        }
-    }
-    if (error != OTBR_ERROR_NONE)
-    {
-        otbrLogWarning("failed to unsubscribe %s: %s", fullName.c_str(), otbrErrorString(error));
-    }
-}
-
-void DiscoveryProxy::OnServiceDiscovered(const std::string &                            aType,
-                                         const Mdns::Publisher::DiscoveredInstanceInfo &aInstanceInfo)
-{
-    otDnssdServiceInstanceInfo instanceInfo;
-    const otDnssdQuery *       query = nullptr;
-
-    otbrLogInfo("service discovered: %s, instance %s hostname %s addresses %zu port %d priority %d "
-                "weight %d",
-                aType.c_str(), aInstanceInfo.mName.c_str(), aInstanceInfo.mHostName.c_str(),
-                aInstanceInfo.mAddresses.size(), aInstanceInfo.mPort, aInstanceInfo.mPriority, aInstanceInfo.mWeight);
-
-    CheckServiceNameSanity(aType);
-    CheckHostnameSanity(aInstanceInfo.mHostName);
-
-    instanceInfo.mAddressNum = aInstanceInfo.mAddresses.size();
-
-    if (!aInstanceInfo.mAddresses.empty())
-    {
-        instanceInfo.mAddresses = reinterpret_cast<const otIp6Address *>(&aInstanceInfo.mAddresses[0]);
-    }
-    else
-    {
-        instanceInfo.mAddresses = nullptr;
-    }
-
-    instanceInfo.mPort      = aInstanceInfo.mPort;
-    instanceInfo.mPriority  = aInstanceInfo.mPriority;
-    instanceInfo.mWeight    = aInstanceInfo.mWeight;
-    instanceInfo.mTxtLength = static_cast<uint16_t>(aInstanceInfo.mTxtData.size());
-    instanceInfo.mTxtData   = aInstanceInfo.mTxtData.data();
-    instanceInfo.mTtl       = CapTtl(aInstanceInfo.mTtl);
-
-    while ((query = otDnssdGetNextQuery(mNcp.GetInstance(), query)) != nullptr)
-    {
-        std::string      instanceName;
-        std::string      serviceName;
-        std::string      hostName;
-        std::string      domain;
-        char             queryName[OT_DNS_MAX_NAME_SIZE];
-        otDnssdQueryType type = otDnssdGetQueryTypeAndName(query, &queryName);
-        otbrError        splitError;
-
-        switch (type)
-        {
-        case OT_DNSSD_QUERY_TYPE_BROWSE:
-            splitError = SplitFullServiceName(queryName, serviceName, domain);
-            assert(splitError == OTBR_ERROR_NONE);
-            break;
-        case OT_DNSSD_QUERY_TYPE_RESOLVE:
-            splitError = SplitFullServiceInstanceName(queryName, instanceName, serviceName, domain);
-            assert(splitError == OTBR_ERROR_NONE);
-            break;
-        default:
-            splitError = OTBR_ERROR_NOT_FOUND;
-            break;
-        }
-        if (splitError != OTBR_ERROR_NONE)
-        {
-            continue;
-        }
-
-        if (serviceName == aType && (instanceName.empty() || instanceName == aInstanceInfo.mName))
-        {
-            std::string serviceFullName  = aType + "." + domain;
-            std::string hostName         = TranslateDomain(aInstanceInfo.mHostName, domain);
-            std::string instanceFullName = aInstanceInfo.mName + "." + serviceFullName;
-
-            instanceInfo.mFullName = instanceFullName.c_str();
-            instanceInfo.mHostName = hostName.c_str();
-
-            otDnssdQueryHandleDiscoveredServiceInstance(mNcp.GetInstance(), serviceFullName.c_str(), &instanceInfo);
-        }
-    }
-}
-
-void DiscoveryProxy::OnHostDiscovered(const std::string &                        aHostName,
-                                      const Mdns::Publisher::DiscoveredHostInfo &aHostInfo)
-{
-    otDnssdHostInfo     hostInfo;
-    const otDnssdQuery *query            = nullptr;
-    std::string         resolvedHostName = aHostInfo.mHostName;
-
-    otbrLogInfo("host discovered: %s hostname %s addresses %zu", aHostName.c_str(), aHostInfo.mHostName.c_str(),
-                aHostInfo.mAddresses.size());
-
-    if (resolvedHostName.empty())
-    {
-        resolvedHostName = aHostName + ".local.";
-    }
-
-    CheckHostnameSanity(resolvedHostName);
-
-    hostInfo.mAddressNum = aHostInfo.mAddresses.size();
-    if (!aHostInfo.mAddresses.empty())
-    {
-        hostInfo.mAddresses = reinterpret_cast<const otIp6Address *>(&aHostInfo.mAddresses[0]);
-    }
-    else
-    {
-        hostInfo.mAddresses = nullptr;
-    }
-
-    hostInfo.mTtl = CapTtl(aHostInfo.mTtl);
-
-    while ((query = otDnssdGetNextQuery(mNcp.GetInstance(), query)) != nullptr)
-    {
-        std::string      hostName, domain;
-        char             queryName[OT_DNS_MAX_NAME_SIZE];
-        otDnssdQueryType type = otDnssdGetQueryTypeAndName(query, &queryName);
-        otbrError        splitError;
-
-        if (type != OT_DNSSD_QUERY_TYPE_RESOLVE_HOST)
-        {
-            continue;
-        }
-        splitError = SplitFullHostName(queryName, hostName, domain);
-        assert(splitError == OTBR_ERROR_NONE);
-
-        if (hostName == aHostName)
-        {
-            std::string hostFullName = TranslateDomain(resolvedHostName, domain);
-
-            otDnssdQueryHandleDiscoveredHost(mNcp.GetInstance(), hostFullName.c_str(), &hostInfo);
-        }
-    }
-}
-
-std::string DiscoveryProxy::TranslateDomain(const std::string &aName, const std::string &aTargetDomain)
-{
-    std::string targetName;
-    std::string hostName;
-    std::string domain;
-
-    VerifyOrExit(OTBR_ERROR_NONE == SplitFullHostName(aName, hostName, domain), targetName = aName);
-    VerifyOrExit(domain == "local.", targetName = aName);
-
-    targetName = hostName + "." + aTargetDomain;
-
-exit:
-    otbrLogDebug("translate domain: %s => %s", aName.c_str(), targetName.c_str());
-    return targetName;
-}
-
-int DiscoveryProxy::GetServiceSubscriptionCount(const DnsNameInfo &aNameInfo) const
-{
-    const otDnssdQuery *query = nullptr;
-    int                 count = 0;
-
-    while ((query = otDnssdGetNextQuery(mNcp.GetInstance(), query)) != nullptr)
-    {
-        char        queryName[OT_DNS_MAX_NAME_SIZE];
-        DnsNameInfo queryInfo;
-
-        otDnssdGetQueryTypeAndName(query, &queryName);
-        queryInfo = SplitFullDnsName(queryName);
-
-        count += (aNameInfo.mInstanceName == queryInfo.mInstanceName &&
-                  aNameInfo.mServiceName == queryInfo.mServiceName && aNameInfo.mHostName == queryInfo.mHostName);
-    }
-
-    return count;
-}
-
-void DiscoveryProxy::CheckServiceNameSanity(const std::string &aType)
-{
-    size_t dotpos;
-
-    OTBR_UNUSED_VARIABLE(aType);
-    OTBR_UNUSED_VARIABLE(dotpos);
-
-    assert(aType.length() > 0);
-    assert(aType[aType.length() - 1] != '.');
-    dotpos = aType.find_first_of('.');
-    assert(dotpos != std::string::npos);
-    assert(dotpos == aType.find_last_of('.'));
-}
-
-void DiscoveryProxy::CheckHostnameSanity(const std::string &aHostName)
-{
-    OTBR_UNUSED_VARIABLE(aHostName);
-
-    assert(aHostName.length() > 0);
-    assert(aHostName[aHostName.length() - 1] == '.');
-}
-
-uint32_t DiscoveryProxy::CapTtl(uint32_t aTtl)
-{
-    return std::min(aTtl, static_cast<uint32_t>(kServiceTtlCapLimit));
-}
-
-} // namespace Dnssd
-} // namespace otbr
-
-#endif // OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
diff --git a/src/agent/discovery_proxy.hpp b/src/agent/discovery_proxy.hpp
deleted file mode 100644
index ac8748bd..00000000
--- a/src/agent/discovery_proxy.hpp
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
- *    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 definition for DNS-SD Discovery Proxy.
- */
-
-#ifndef OTBR_AGENT_DISCOVERY_PROXY_HPP_
-#define OTBR_AGENT_DISCOVERY_PROXY_HPP_
-
-#if OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-
-#include <set>
-#include <utility>
-
-#include <stdint.h>
-
-#include <openthread/dnssd_server.h>
-#include <openthread/instance.h>
-
-#include "agent/ncp_openthread.hpp"
-#include "common/dns_utils.hpp"
-#include "mdns/mdns.hpp"
-
-namespace otbr {
-namespace Dnssd {
-
-/**
- * This class implements the DNS-SD Discovery Proxy.
- *
- */
-class DiscoveryProxy
-{
-public:
-    /**
-     * This constructor initializes the Discovery Proxy instance.
-     *
-     * @param[in] aNcp        A reference to the OpenThread Controller instance.
-     * @param[in] aPublisher  A reference to the mDNS Publisher.
-     *
-     */
-    explicit DiscoveryProxy(Ncp::ControllerOpenThread &aNcp, Mdns::Publisher &aPublisher);
-
-    /**
-     * This method starts the Discovery Proxy.
-     *
-     */
-    void Start(void);
-
-    /**
-     * This method stops the Discovery Proxy.
-     *
-     */
-    void Stop(void);
-
-private:
-    enum : uint32_t
-    {
-        kServiceTtlCapLimit = 10, // TTL cap limit for Discovery Proxy (in seconds).
-    };
-
-    static void        OnDiscoveryProxySubscribe(void *aContext, const char *aFullName);
-    void               OnDiscoveryProxySubscribe(const char *aSubscription);
-    static void        OnDiscoveryProxyUnsubscribe(void *aContext, const char *aFullName);
-    void               OnDiscoveryProxyUnsubscribe(const char *aSubscription);
-    int                GetServiceSubscriptionCount(const DnsNameInfo &aNameInfo) const;
-    static std::string TranslateDomain(const std::string &aName, const std::string &aTargetDomain);
-    static void        CheckServiceNameSanity(const std::string &aType);
-    static void        CheckHostnameSanity(const std::string &aHostName);
-    void               OnServiceDiscovered(const std::string &                            aSubscription,
-                                           const Mdns::Publisher::DiscoveredInstanceInfo &aInstanceInfo);
-    void OnHostDiscovered(const std::string &aHostName, const Mdns::Publisher::DiscoveredHostInfo &aHostInfo);
-    static uint32_t CapTtl(uint32_t aTtl);
-
-    Ncp::ControllerOpenThread &mNcp;
-    Mdns::Publisher &          mMdnsPublisher;
-};
-
-} // namespace Dnssd
-} // namespace otbr
-
-#endif // OTBR_ENABLE_DNSSD_DISCOVERY_PROXY
-
-#endif // OTBR_AGENT_DISCOVERY_PROXY_HPP_
diff --git a/src/agent/main.cpp b/src/agent/main.cpp
index 32c27e51..41a1f8e9 100644
--- a/src/agent/main.cpp
+++ b/src/agent/main.cpp
@@ -46,11 +46,11 @@
 #include <openthread/platform/radio.h>
 
 #include "agent/agent_instance.hpp"
-#include "agent/ncp_openthread.hpp"
 #include "common/code_utils.hpp"
 #include "common/logging.hpp"
 #include "common/mainloop.hpp"
 #include "common/types.hpp"
+#include "ncp/ncp_openthread.hpp"
 #if OTBR_ENABLE_REST_SERVER
 #include "rest/rest_web_server.hpp"
 using otbr::rest::RestWebServer;
diff --git a/src/agent/ncp_openthread.cpp b/src/agent/ncp_openthread.cpp
deleted file mode 100644
index a6659cd4..00000000
--- a/src/agent/ncp_openthread.cpp
+++ /dev/null
@@ -1,288 +0,0 @@
-/*
- *    Copyright (c) 2019, 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.
- */
-
-#define OTBR_LOG_TAG "AGENT"
-
-#include "agent/ncp_openthread.hpp"
-
-#include <assert.h>
-#include <stdio.h>
-#include <string.h>
-
-#include <openthread/backbone_router_ftd.h>
-#include <openthread/dataset.h>
-#include <openthread/logging.h>
-#include <openthread/srp_server.h>
-#include <openthread/tasklet.h>
-#include <openthread/thread.h>
-#include <openthread/thread_ftd.h>
-#include <openthread/platform/logging.h>
-#include <openthread/platform/misc.h>
-#include <openthread/platform/radio.h>
-#include <openthread/platform/settings.h>
-
-#include "common/code_utils.hpp"
-#include "common/logging.hpp"
-#include "common/types.hpp"
-
-#if OTBR_ENABLE_LEGACY
-#include <ot-legacy-pairing-ext.h>
-#endif
-
-namespace otbr {
-namespace Ncp {
-
-static const uint16_t kThreadVersion11 = 2; ///< Thread Version 1.1
-static const uint16_t kThreadVersion12 = 3; ///< Thread Version 1.2
-
-ControllerOpenThread::ControllerOpenThread(const char *                     aInterfaceName,
-                                           const std::vector<const char *> &aRadioUrls,
-                                           const char *                     aBackboneInterfaceName)
-    : mInstance(nullptr)
-{
-    VerifyOrDie(aRadioUrls.size() <= OT_PLATFORM_CONFIG_MAX_RADIO_URLS, "Too many Radio URLs!");
-
-    memset(&mConfig, 0, sizeof(mConfig));
-
-    mConfig.mInterfaceName         = aInterfaceName;
-    mConfig.mBackboneInterfaceName = aBackboneInterfaceName;
-    for (const char *url : aRadioUrls)
-    {
-        mConfig.mRadioUrls[mConfig.mRadioUrlNum++] = url;
-    }
-    mConfig.mSpeedUpFactor = 1;
-}
-
-ControllerOpenThread::~ControllerOpenThread(void)
-{
-    otSysDeinit();
-}
-
-otbrError ControllerOpenThread::Init(void)
-{
-    otbrError  error = OTBR_ERROR_NONE;
-    otLogLevel level = OT_LOG_LEVEL_NONE;
-
-    switch (otbrLogGetLevel())
-    {
-    case OTBR_LOG_EMERG:
-    case OTBR_LOG_ALERT:
-    case OTBR_LOG_CRIT:
-        level = OT_LOG_LEVEL_CRIT;
-        break;
-    case OTBR_LOG_ERR:
-    case OTBR_LOG_WARNING:
-        level = OT_LOG_LEVEL_WARN;
-        break;
-    case OTBR_LOG_NOTICE:
-        level = OT_LOG_LEVEL_NOTE;
-        break;
-    case OTBR_LOG_INFO:
-        level = OT_LOG_LEVEL_INFO;
-        break;
-    case OTBR_LOG_DEBUG:
-        level = OT_LOG_LEVEL_DEBG;
-        break;
-    default:
-        ExitNow(error = OTBR_ERROR_OPENTHREAD);
-        break;
-    }
-    VerifyOrExit(otLoggingSetLevel(level) == OT_ERROR_NONE, error = OTBR_ERROR_OPENTHREAD);
-
-    mInstance = otSysInit(&mConfig);
-    assert(mInstance != nullptr);
-
-#if OTBR_ENABLE_LEGACY
-    otLegacyInit();
-#endif
-
-    {
-        otError result = otSetStateChangedCallback(mInstance, &ControllerOpenThread::HandleStateChanged, this);
-
-        agent::ThreadHelper::LogOpenThreadResult("Set state callback", result);
-        VerifyOrExit(result == OT_ERROR_NONE, error = OTBR_ERROR_OPENTHREAD);
-    }
-
-#if OTBR_ENABLE_SRP_ADVERTISING_PROXY
-    otSrpServerSetEnabled(mInstance, /* aEnabled */ true);
-#endif
-
-    mThreadHelper = std::unique_ptr<otbr::agent::ThreadHelper>(new otbr::agent::ThreadHelper(mInstance, this));
-
-exit:
-    return error;
-}
-
-void ControllerOpenThread::HandleStateChanged(otChangedFlags aFlags)
-{
-    if (aFlags & OT_CHANGED_THREAD_ROLE)
-    {
-        switch (otThreadGetDeviceRole(mInstance))
-        {
-        case OT_DEVICE_ROLE_DISABLED:
-#if OTBR_ENABLE_LEGACY
-            otLegacyStop();
-#endif
-            break;
-        case OT_DEVICE_ROLE_CHILD:
-        case OT_DEVICE_ROLE_ROUTER:
-        case OT_DEVICE_ROLE_LEADER:
-#if OTBR_ENABLE_LEGACY
-            otLegacyStart();
-#endif
-            break;
-        default:
-            break;
-        }
-    }
-
-    for (auto &stateCallback : mThreadStateChangedCallbacks)
-    {
-        stateCallback(aFlags);
-    }
-
-    mThreadHelper->StateChangedCallback(aFlags);
-}
-
-void ControllerOpenThread::Update(MainloopContext &aMainloop)
-{
-    mTaskRunner.Update(aMainloop);
-
-    if (otTaskletsArePending(mInstance))
-    {
-        aMainloop.mTimeout = ToTimeval(Microseconds::zero());
-    }
-
-    otSysMainloopUpdate(mInstance, &aMainloop);
-}
-
-void ControllerOpenThread::Process(const MainloopContext &aMainloop)
-{
-    otTaskletsProcess(mInstance);
-
-    otSysMainloopProcess(mInstance, &aMainloop);
-
-    mTaskRunner.Process(aMainloop);
-
-    if (getenv("OTBR_NO_AUTO_ATTACH") == nullptr && mThreadHelper->TryResumeNetwork() == OT_ERROR_NONE)
-    {
-        setenv("OTBR_NO_AUTO_ATTACH", "1", 0);
-    }
-}
-
-void ControllerOpenThread::PostTimerTask(Milliseconds aDelay, TaskRunner::Task<void> aTask)
-{
-    mTaskRunner.Post(std::move(aDelay), std::move(aTask));
-}
-
-void ControllerOpenThread::RegisterResetHandler(std::function<void(void)> aHandler)
-{
-    mResetHandlers.emplace_back(std::move(aHandler));
-}
-
-void ControllerOpenThread::AddThreadStateChangedCallback(ThreadStateChangedCallback aCallback)
-{
-    mThreadStateChangedCallbacks.emplace_back(std::move(aCallback));
-}
-
-void ControllerOpenThread::Reset(void)
-{
-    gPlatResetReason = OT_PLAT_RESET_REASON_SOFTWARE;
-
-    otSysDeinit();
-    mInstance = nullptr;
-
-    Init();
-    for (auto &handler : mResetHandlers)
-    {
-        handler();
-    }
-    unsetenv("OTBR_NO_AUTO_ATTACH");
-}
-
-const char *ControllerOpenThread::GetThreadVersion(void)
-{
-    const char *version;
-
-    switch (otThreadGetVersion())
-    {
-    case kThreadVersion11:
-        version = "1.1.1";
-        break;
-    case kThreadVersion12:
-        version = "1.2.0";
-        break;
-    default:
-        otbrLogEmerg("Unexpected thread version %hu", otThreadGetVersion());
-        exit(-1);
-    }
-    return version;
-}
-
-/*
- * Provide, if required an "otPlatLog()" function
- */
-extern "C" void otPlatLog(otLogLevel aLogLevel, otLogRegion aLogRegion, const char *aFormat, ...)
-{
-    OT_UNUSED_VARIABLE(aLogRegion);
-
-    otbrLogLevel otbrLogLevel;
-
-    switch (aLogLevel)
-    {
-    case OT_LOG_LEVEL_NONE:
-        otbrLogLevel = OTBR_LOG_EMERG;
-        break;
-    case OT_LOG_LEVEL_CRIT:
-        otbrLogLevel = OTBR_LOG_CRIT;
-        break;
-    case OT_LOG_LEVEL_WARN:
-        otbrLogLevel = OTBR_LOG_WARNING;
-        break;
-    case OT_LOG_LEVEL_NOTE:
-        otbrLogLevel = OTBR_LOG_NOTICE;
-        break;
-    case OT_LOG_LEVEL_INFO:
-        otbrLogLevel = OTBR_LOG_INFO;
-        break;
-    case OT_LOG_LEVEL_DEBG:
-        otbrLogLevel = OTBR_LOG_DEBUG;
-        break;
-    default:
-        otbrLogLevel = OTBR_LOG_DEBUG;
-        break;
-    }
-
-    va_list ap;
-    va_start(ap, aFormat);
-    otbrLogvNoFilter(otbrLogLevel, aFormat, ap);
-    va_end(ap);
-}
-
-} // namespace Ncp
-} // namespace otbr
diff --git a/src/agent/ncp_openthread.hpp b/src/agent/ncp_openthread.hpp
deleted file mode 100644
index 11aa8358..00000000
--- a/src/agent/ncp_openthread.hpp
+++ /dev/null
@@ -1,187 +0,0 @@
-/*
- *  Copyright (c) 2017, 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 for NCP service.
- */
-
-#ifndef OTBR_AGENT_NCP_OPENTHREAD_HPP_
-#define OTBR_AGENT_NCP_OPENTHREAD_HPP_
-
-#include <chrono>
-#include <memory>
-
-#include <openthread/backbone_router_ftd.h>
-#include <openthread/cli.h>
-#include <openthread/instance.h>
-#include <openthread/openthread-system.h>
-
-#include "agent/thread_helper.hpp"
-#include "common/mainloop.hpp"
-#include "common/task_runner.hpp"
-#include "common/types.hpp"
-
-namespace otbr {
-namespace Ncp {
-
-/**
- * This interface defines NCP Controller functionality.
- *
- */
-class ControllerOpenThread : public MainloopProcessor
-{
-public:
-    using ThreadStateChangedCallback = std::function<void(otChangedFlags aFlags)>;
-
-    /**
-     * This constructor initializes this object.
-     *
-     * @param[in]   aInterfaceName          A string of the NCP interface name.
-     * @param[in]   aRadioUrls              The radio URLs (can be IEEE802.15.4 or TREL radio).
-     * @param[in]   aBackboneInterfaceName  The Backbone network interface name.
-     *
-     */
-    ControllerOpenThread(const char *                     aInterfaceName,
-                         const std::vector<const char *> &aRadioUrls,
-                         const char *                     aBackboneInterfaceName);
-
-    /**
-     * This method initalize the NCP controller.
-     *
-     * @retval  OTBR_ERROR_NONE     Successfully initialized NCP controller.
-     *
-     */
-    otbrError Init(void);
-
-    /**
-     * This method get mInstance pointer.
-     *
-     * @retval  the pointer of mInstance.
-     *
-     */
-    otInstance *GetInstance(void) { return mInstance; }
-
-    /**
-     * This method gets the thread functionality helper.
-     *
-     * @retval  the pointer to the helper object.
-     *
-     */
-    otbr::agent::ThreadHelper *GetThreadHelper(void) { return mThreadHelper.get(); }
-
-    /**
-     * This method updates the mainloop context.
-     *
-     * @param[inout]  aMainloop  A reference to the mainloop to be updated.
-     *
-     */
-    void Update(MainloopContext &aMainloop) override;
-
-    /**
-     * This method processes mainloop events.
-     *
-     * @param[in]  aMainloop  A reference to the mainloop context.
-     *
-     */
-    void Process(const MainloopContext &aMainloop) override;
-
-    /**
-     * This method posts a task to the timer
-     *
-     * @param[in]   aDelay  The delay in milliseconds before executing the task.
-     * @param[in]   aTask   The task function.
-     *
-     */
-    void PostTimerTask(Milliseconds aDelay, TaskRunner::Task<void> aTask);
-
-    /**
-     * This method registers a reset handler.
-     *
-     * @param[in]   aHandler  The handler function.
-     *
-     */
-    void RegisterResetHandler(std::function<void(void)> aHandler);
-
-    /**
-     * This method adds a event listener for Thread state changes.
-     *
-     * @param[in]  aCallback  The callback to receive Thread state changed events.
-     *
-     */
-    void AddThreadStateChangedCallback(ThreadStateChangedCallback aCallback);
-
-    /**
-     * This method resets the OpenThread instance.
-     *
-     */
-    void Reset(void);
-
-    /**
-     * This method returns the Thread protocol version as a string.
-     *
-     * @returns  A pointer to the Thread version string.
-     *
-     */
-    static const char *GetThreadVersion(void);
-
-    ~ControllerOpenThread(void) override;
-
-private:
-    static void HandleStateChanged(otChangedFlags aFlags, void *aContext)
-    {
-        static_cast<ControllerOpenThread *>(aContext)->HandleStateChanged(aFlags);
-    }
-    void HandleStateChanged(otChangedFlags aFlags);
-
-    static void HandleBackboneRouterDomainPrefixEvent(void *                            aContext,
-                                                      otBackboneRouterDomainPrefixEvent aEvent,
-                                                      const otIp6Prefix *               aDomainPrefix);
-    void        HandleBackboneRouterDomainPrefixEvent(otBackboneRouterDomainPrefixEvent aEvent,
-                                                      const otIp6Prefix *               aDomainPrefix);
-
-#if OTBR_ENABLE_DUA_ROUTING
-    static void HandleBackboneRouterNdProxyEvent(void *                       aContext,
-                                                 otBackboneRouterNdProxyEvent aEvent,
-                                                 const otIp6Address *         aAddress);
-    void        HandleBackboneRouterNdProxyEvent(otBackboneRouterNdProxyEvent aEvent, const otIp6Address *aAddress);
-#endif
-
-    otInstance *mInstance;
-
-    otPlatformConfig                           mConfig;
-    std::unique_ptr<otbr::agent::ThreadHelper> mThreadHelper;
-    std::vector<std::function<void(void)>>     mResetHandlers;
-    TaskRunner                                 mTaskRunner;
-    std::vector<ThreadStateChangedCallback>    mThreadStateChangedCallbacks;
-};
-
-} // namespace Ncp
-} // namespace otbr
-
-#endif // OTBR_AGENT_NCP_OPENTHREAD_HPP_
diff --git a/src/agent/thread_helper.cpp b/src/agent/thread_helper.cpp
deleted file mode 100644
index f6e7eb26..00000000
--- a/src/agent/thread_helper.cpp
+++ /dev/null
@@ -1,450 +0,0 @@
-/*
- *    Copyright (c) 2020, 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.
- */
-
-#define OTBR_LOG_TAG "AGENT"
-
-#include "agent/thread_helper.hpp"
-
-#include <assert.h>
-#include <limits.h>
-#include <string.h>
-
-#include <string>
-
-#include <openthread/border_router.h>
-#include <openthread/channel_manager.h>
-#include <openthread/jam_detection.h>
-#include <openthread/joiner.h>
-#include <openthread/thread_ftd.h>
-#include <openthread/platform/radio.h>
-
-#include "agent/ncp_openthread.hpp"
-#include "common/byteswap.hpp"
-#include "common/code_utils.hpp"
-#include "common/logging.hpp"
-
-namespace otbr {
-namespace agent {
-
-ThreadHelper::ThreadHelper(otInstance *aInstance, otbr::Ncp::ControllerOpenThread *aNcp)
-    : mInstance(aInstance)
-    , mNcp(aNcp)
-{
-}
-
-void ThreadHelper::StateChangedCallback(otChangedFlags aFlags)
-{
-    if (aFlags & OT_CHANGED_THREAD_ROLE)
-    {
-        otDeviceRole role = otThreadGetDeviceRole(mInstance);
-
-        for (const auto &handler : mDeviceRoleHandlers)
-        {
-            handler(role);
-        }
-
-        if (role != OT_DEVICE_ROLE_DISABLED && role != OT_DEVICE_ROLE_DETACHED)
-        {
-            if (mAttachHandler != nullptr)
-            {
-                mAttachHandler(OT_ERROR_NONE);
-                mAttachHandler = nullptr;
-            }
-            else if (mJoinerHandler != nullptr)
-            {
-                mJoinerHandler(OT_ERROR_NONE);
-                mJoinerHandler = nullptr;
-            }
-        }
-    }
-}
-
-void ThreadHelper::AddDeviceRoleHandler(DeviceRoleHandler aHandler)
-{
-    mDeviceRoleHandlers.emplace_back(aHandler);
-}
-
-void ThreadHelper::Scan(ScanHandler aHandler)
-{
-    otError error = OT_ERROR_NONE;
-
-    VerifyOrExit(aHandler != nullptr);
-    mScanHandler = aHandler;
-    mScanResults.clear();
-
-    error =
-        otLinkActiveScan(mInstance, /*scanChannels =*/0, /*scanDuration=*/0, &ThreadHelper::sActiveScanHandler, this);
-
-exit:
-    if (error != OT_ERROR_NONE)
-    {
-        if (aHandler)
-        {
-            mScanHandler(error, {});
-        }
-        mScanHandler = nullptr;
-    }
-}
-
-void ThreadHelper::RandomFill(void *aBuf, size_t size)
-{
-    std::uniform_int_distribution<> dist(0, UINT8_MAX);
-    uint8_t *                       buf = static_cast<uint8_t *>(aBuf);
-
-    for (size_t i = 0; i < size; i++)
-    {
-        buf[i] = static_cast<uint8_t>(dist(mRandomDevice));
-    }
-}
-
-void ThreadHelper::sActiveScanHandler(otActiveScanResult *aResult, void *aThreadHelper)
-{
-    ThreadHelper *helper = static_cast<ThreadHelper *>(aThreadHelper);
-
-    helper->ActiveScanHandler(aResult);
-}
-
-void ThreadHelper::ActiveScanHandler(otActiveScanResult *aResult)
-{
-    if (aResult == nullptr)
-    {
-        if (mScanHandler != nullptr)
-        {
-            mScanHandler(OT_ERROR_NONE, mScanResults);
-        }
-    }
-    else
-    {
-        mScanResults.push_back(*aResult);
-    }
-}
-
-uint8_t ThreadHelper::RandomChannelFromChannelMask(uint32_t aChannelMask)
-{
-    // 8 bit per byte
-    constexpr uint8_t kNumChannels = sizeof(aChannelMask) * 8;
-    uint8_t           channels[kNumChannels];
-    uint8_t           numValidChannels = 0;
-
-    for (uint8_t i = 0; i < kNumChannels; i++)
-    {
-        if (aChannelMask & (1 << i))
-        {
-            channels[numValidChannels++] = i;
-        }
-    }
-
-    return channels[std::uniform_int_distribution<unsigned int>(0, numValidChannels - 1)(mRandomDevice)];
-}
-
-static otExtendedPanId ToOtExtendedPanId(uint64_t aExtPanId)
-{
-    otExtendedPanId extPanId;
-    uint64_t        mask = UINT8_MAX;
-
-    for (size_t i = 0; i < sizeof(uint64_t); i++)
-    {
-        extPanId.m8[i] = static_cast<uint8_t>((aExtPanId >> ((sizeof(uint64_t) - i - 1) * 8)) & mask);
-    }
-
-    return extPanId;
-}
-
-void ThreadHelper::Attach(const std::string &         aNetworkName,
-                          uint16_t                    aPanId,
-                          uint64_t                    aExtPanId,
-                          const std::vector<uint8_t> &aNetworkKey,
-                          const std::vector<uint8_t> &aPSKc,
-                          uint32_t                    aChannelMask,
-                          ResultHandler               aHandler)
-
-{
-    otError         error = OT_ERROR_NONE;
-    otExtendedPanId extPanId;
-    otNetworkKey    networkKey;
-    otPskc          pskc;
-    uint32_t        channelMask;
-    uint8_t         channel;
-
-    VerifyOrExit(aHandler != nullptr, error = OT_ERROR_INVALID_ARGS);
-    VerifyOrExit(mAttachHandler == nullptr && mJoinerHandler == nullptr, error = OT_ERROR_INVALID_STATE);
-    mAttachHandler = aHandler;
-    VerifyOrExit(aNetworkKey.empty() || aNetworkKey.size() == sizeof(networkKey.m8), error = OT_ERROR_INVALID_ARGS);
-    VerifyOrExit(aPSKc.empty() || aPSKc.size() == sizeof(pskc.m8), error = OT_ERROR_INVALID_ARGS);
-    VerifyOrExit(aChannelMask != 0, error = OT_ERROR_INVALID_ARGS);
-
-    while (aPanId == UINT16_MAX)
-    {
-        RandomFill(&aPanId, sizeof(aPanId));
-    }
-
-    if (aExtPanId != UINT64_MAX)
-    {
-        extPanId = ToOtExtendedPanId(aExtPanId);
-    }
-    else
-    {
-        *reinterpret_cast<uint64_t *>(&extPanId) = UINT64_MAX;
-
-        while (*reinterpret_cast<uint64_t *>(&extPanId) == UINT64_MAX)
-        {
-            RandomFill(extPanId.m8, sizeof(extPanId.m8));
-        }
-    }
-
-    if (!aNetworkKey.empty())
-    {
-        memcpy(networkKey.m8, &aNetworkKey[0], sizeof(networkKey.m8));
-    }
-    else
-    {
-        RandomFill(networkKey.m8, sizeof(networkKey.m8));
-    }
-
-    if (!aPSKc.empty())
-    {
-        memcpy(pskc.m8, &aPSKc[0], sizeof(pskc.m8));
-    }
-    else
-    {
-        RandomFill(pskc.m8, sizeof(pskc.m8));
-    }
-
-    if (!otIp6IsEnabled(mInstance))
-    {
-        SuccessOrExit(error = otIp6SetEnabled(mInstance, true));
-    }
-
-    SuccessOrExit(error = otThreadSetNetworkName(mInstance, aNetworkName.c_str()));
-    SuccessOrExit(error = otLinkSetPanId(mInstance, aPanId));
-    SuccessOrExit(error = otThreadSetExtendedPanId(mInstance, &extPanId));
-    SuccessOrExit(error = otThreadSetNetworkKey(mInstance, &networkKey));
-
-    channelMask = otPlatRadioGetPreferredChannelMask(mInstance) & aChannelMask;
-
-    if (channelMask == 0)
-    {
-        channelMask = otLinkGetSupportedChannelMask(mInstance) & aChannelMask;
-    }
-    VerifyOrExit(channelMask != 0, otbrLogWarning("Invalid channel mask"), error = OT_ERROR_INVALID_ARGS);
-
-    channel = RandomChannelFromChannelMask(channelMask);
-    SuccessOrExit(otLinkSetChannel(mInstance, channel));
-
-    SuccessOrExit(error = otThreadSetPskc(mInstance, &pskc));
-
-    SuccessOrExit(error = otThreadSetEnabled(mInstance, true));
-exit:
-    if (error != OT_ERROR_NONE)
-    {
-        if (aHandler)
-        {
-            aHandler(error);
-        }
-        mAttachHandler = nullptr;
-    }
-}
-
-void ThreadHelper::Attach(ResultHandler aHandler)
-{
-    otError error = OT_ERROR_NONE;
-
-    VerifyOrExit(mAttachHandler == nullptr && mJoinerHandler == nullptr, error = OT_ERROR_INVALID_STATE);
-    mAttachHandler = aHandler;
-
-    if (!otIp6IsEnabled(mInstance))
-    {
-        SuccessOrExit(error = otIp6SetEnabled(mInstance, true));
-    }
-    SuccessOrExit(error = otThreadSetEnabled(mInstance, true));
-
-exit:
-    if (error != OT_ERROR_NONE)
-    {
-        if (aHandler)
-        {
-            aHandler(error);
-        }
-        mAttachHandler = nullptr;
-    }
-}
-
-otError ThreadHelper::Detach(void)
-{
-    otError error = OT_ERROR_NONE;
-
-    SuccessOrExit(error = otThreadSetEnabled(mInstance, false));
-    SuccessOrExit(error = otIp6SetEnabled(mInstance, false));
-
-exit:
-    return error;
-}
-
-otError ThreadHelper::Reset(void)
-{
-    mDeviceRoleHandlers.clear();
-    otInstanceReset(mInstance);
-
-    return OT_ERROR_NONE;
-}
-
-void ThreadHelper::JoinerStart(const std::string &aPskd,
-                               const std::string &aProvisioningUrl,
-                               const std::string &aVendorName,
-                               const std::string &aVendorModel,
-                               const std::string &aVendorSwVersion,
-                               const std::string &aVendorData,
-                               ResultHandler      aHandler)
-{
-    otError error = OT_ERROR_NONE;
-
-    VerifyOrExit(aHandler != nullptr, error = OT_ERROR_INVALID_ARGS);
-    VerifyOrExit(mAttachHandler == nullptr && mJoinerHandler == nullptr, error = OT_ERROR_INVALID_STATE);
-    mJoinerHandler = aHandler;
-
-    if (!otIp6IsEnabled(mInstance))
-    {
-        SuccessOrExit(error = otIp6SetEnabled(mInstance, true));
-    }
-    error = otJoinerStart(mInstance, aPskd.c_str(), aProvisioningUrl.c_str(), aVendorName.c_str(), aVendorModel.c_str(),
-                          aVendorSwVersion.c_str(), aVendorData.c_str(), sJoinerCallback, this);
-exit:
-    if (error != OT_ERROR_NONE)
-    {
-        if (aHandler)
-        {
-            aHandler(error);
-        }
-        mJoinerHandler = nullptr;
-    }
-}
-
-void ThreadHelper::sJoinerCallback(otError aError, void *aThreadHelper)
-{
-    ThreadHelper *helper = static_cast<ThreadHelper *>(aThreadHelper);
-
-    helper->JoinerCallback(aError);
-}
-
-void ThreadHelper::JoinerCallback(otError aError)
-{
-    if (aError != OT_ERROR_NONE)
-    {
-        otbrLogWarning("Failed to join Thread network: %s", otThreadErrorToString(aError));
-        mJoinerHandler(aError);
-        mJoinerHandler = nullptr;
-    }
-    else
-    {
-        LogOpenThreadResult("Start Thread network", otThreadSetEnabled(mInstance, true));
-    }
-}
-
-otError ThreadHelper::TryResumeNetwork(void)
-{
-    otError error = OT_ERROR_NONE;
-
-    if (otLinkGetPanId(mInstance) != UINT16_MAX && otThreadGetDeviceRole(mInstance) == OT_DEVICE_ROLE_DISABLED)
-    {
-        if (!otIp6IsEnabled(mInstance))
-        {
-            SuccessOrExit(error = otIp6SetEnabled(mInstance, true));
-            SuccessOrExit(error = otThreadSetEnabled(mInstance, true));
-        }
-    }
-
-exit:
-    if (error != OT_ERROR_NONE)
-    {
-        (void)otIp6SetEnabled(mInstance, false);
-    }
-
-    return error;
-}
-
-void ThreadHelper::LogOpenThreadResult(const char *aAction, otError aError)
-{
-    if (aError == OT_ERROR_NONE)
-    {
-        otbrLogInfo("%s: %s", aAction, otThreadErrorToString(aError));
-    }
-    else
-    {
-        otbrLogWarning("%s: %s", aAction, otThreadErrorToString(aError));
-    }
-}
-
-#if OTBR_ENABLE_UNSECURE_JOIN
-otError ThreadHelper::PermitUnsecureJoin(uint16_t aPort, uint32_t aSeconds)
-{
-    otError      error = OT_ERROR_NONE;
-    otExtAddress steeringData;
-
-    // 0xff to allow all devices to join
-    memset(&steeringData.m8, 0xff, sizeof(steeringData.m8));
-    SuccessOrExit(error = otIp6AddUnsecurePort(mInstance, aPort));
-    otThreadSetSteeringData(mInstance, &steeringData);
-
-    if (aSeconds > 0)
-    {
-        auto delay = Milliseconds(aSeconds * 1000);
-
-        ++mUnsecurePortRefCounter[aPort];
-
-        mNcp->PostTimerTask(delay, [this, aPort]() {
-            assert(mUnsecurePortRefCounter.find(aPort) != mUnsecurePortRefCounter.end());
-            assert(mUnsecurePortRefCounter[aPort] > 0);
-
-            if (--mUnsecurePortRefCounter[aPort] == 0)
-            {
-                otExtAddress noneAddress;
-
-                // 0 to clean steering data
-                memset(&noneAddress.m8, 0, sizeof(noneAddress.m8));
-                (void)otIp6RemoveUnsecurePort(mInstance, aPort);
-                otThreadSetSteeringData(mInstance, &noneAddress);
-                mUnsecurePortRefCounter.erase(aPort);
-            }
-        });
-    }
-    else
-    {
-        otExtAddress noneAddress;
-
-        memset(&noneAddress.m8, 0, sizeof(noneAddress.m8));
-        (void)otIp6RemoveUnsecurePort(mInstance, aPort);
-        otThreadSetSteeringData(mInstance, &noneAddress);
-    }
-
-exit:
-    return error;
-}
-#endif
-
-} // namespace agent
-} // namespace otbr
diff --git a/src/agent/thread_helper.hpp b/src/agent/thread_helper.hpp
deleted file mode 100644
index 8edab39a..00000000
--- a/src/agent/thread_helper.hpp
+++ /dev/null
@@ -1,240 +0,0 @@
-/*
- *    Copyright (c) 2020, 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 for Thread helper.
- */
-
-#ifndef OTBR_THREAD_HELPER_HPP_
-#define OTBR_THREAD_HELPER_HPP_
-
-#include <chrono>
-#include <functional>
-#include <map>
-#include <random>
-#include <string>
-#include <vector>
-
-#include <openthread/instance.h>
-#include <openthread/ip6.h>
-#include <openthread/jam_detection.h>
-#include <openthread/joiner.h>
-#include <openthread/netdata.h>
-#include <openthread/thread.h>
-
-namespace otbr {
-namespace Ncp {
-class ControllerOpenThread;
-}
-} // namespace otbr
-
-namespace otbr {
-namespace agent {
-
-/**
- * This class implements Thread helper.
- */
-class ThreadHelper
-{
-public:
-    using DeviceRoleHandler = std::function<void(otDeviceRole)>;
-    using ScanHandler       = std::function<void(otError, const std::vector<otActiveScanResult> &)>;
-    using ResultHandler     = std::function<void(otError)>;
-
-    /**
-     * The constructor of a Thread helper.
-     *
-     * @param[in]   aInstance  The Thread instance.
-     * @param[in]   aNcp       The ncp controller.
-     *
-     */
-    ThreadHelper(otInstance *aInstance, otbr::Ncp::ControllerOpenThread *aNcp);
-
-    /**
-     * This method adds a callback for device role change.
-     *
-     * @param[in]   aHandler  The device role handler.
-     *
-     */
-    void AddDeviceRoleHandler(DeviceRoleHandler aHandler);
-
-    /**
-     * This method permits unsecure join on port.
-     *
-     * @param[in]   aPort     The port number.
-     * @param[in]   aSeconds  The timeout to close the port, 0 for never close.
-     *
-     * @returns The error value of underlying OpenThread api calls.
-     *
-     */
-    otError PermitUnsecureJoin(uint16_t aPort, uint32_t aSeconds);
-
-    /**
-     * This method performs a Thread network scan.
-     *
-     * @param[in]   aHandler  The scan result handler.
-     *
-     */
-    void Scan(ScanHandler aHandler);
-
-    /**
-     * This method attaches the device to the Thread network.
-     *
-     * @note The joiner start and the attach proccesses are exclusive
-     *
-     * @param[in]   aNetworkName    The network name.
-     * @param[in]   aPanId          The pan id, UINT16_MAX for random.
-     * @param[in]   aExtPanId       The extended pan id, UINT64_MAX for random.
-     * @param[in]   aNetworkKey     The network key, empty for random.
-     * @param[in]   aPSKc           The pre-shared commissioner key, empty for random.
-     * @param[in]   aChannelMask    A bitmask for valid channels, will random select one.
-     * @param[in]   aHandler        The attach result handler.
-     *
-     */
-    void Attach(const std::string &         aNetworkName,
-                uint16_t                    aPanId,
-                uint64_t                    aExtPanId,
-                const std::vector<uint8_t> &aNetworkKey,
-                const std::vector<uint8_t> &aPSKc,
-                uint32_t                    aChannelMask,
-                ResultHandler               aHandler);
-
-    /**
-     * This method detaches the device from the Thread network.
-     *
-     * @returns The error value of underlying OpenThread API calls.
-     *
-     */
-    otError Detach(void);
-
-    /**
-     * This method attaches the device to the Thread network.
-     *
-     * @note The joiner start and the attach proccesses are exclusive, and the
-     *       network parameter will be set through the active dataset.
-     *
-     * @param[in]   aHandler        The attach result handler.
-     *
-     */
-    void Attach(ResultHandler aHandler);
-
-    /**
-     * This method resets the OpenThread stack.
-     *
-     * @returns The error value of underlying OpenThread api calls.
-     *
-     */
-    otError Reset(void);
-
-    /**
-     * This method triggers a thread join process.
-     *
-     * @note The joiner start and the attach proccesses are exclusive
-     *
-     * @param[in]   aPskd             The pre-shared key for device.
-     * @param[in]   aProvisioningUrl  The provision url.
-     * @param[in]   aVendorName       The vendor name.
-     * @param[in]   aVendorModel      The vendor model.
-     * @param[in]   aVendorSwVersion  The vendor software version.
-     * @param[in]   aVendorData       The vendor custom data.
-     * @param[in]   aHandler          The join result handler.
-     *
-     */
-    void JoinerStart(const std::string &aPskd,
-                     const std::string &aProvisioningUrl,
-                     const std::string &aVendorName,
-                     const std::string &aVendorModel,
-                     const std::string &aVendorSwVersion,
-                     const std::string &aVendorData,
-                     ResultHandler      aHandler);
-
-    /**
-     * This method tries to restore the network after reboot
-     *
-     * @returns The error value of underlying OpenThread api calls.
-     *
-     */
-    otError TryResumeNetwork(void);
-
-    /**
-     * This method returns the underlying OpenThread instance.
-     *
-     * @returns The underlying instance.
-     *
-     */
-    otInstance *GetInstance(void) { return mInstance; }
-
-    /**
-     * This method handles OpenThread state changed notification.
-     *
-     * @param[in]  aFlags    A bit-field indicating specific state that has changed.  See `OT_CHANGED_*` definitions.
-     *
-     */
-    void StateChangedCallback(otChangedFlags aFlags);
-
-    /**
-     * This method logs OpenThread action result.
-     *
-     * @param[in] aAction   The action OpenThread performs.
-     * @param[in] aError    The action result.
-     *
-     */
-    static void LogOpenThreadResult(const char *aAction, otError aError);
-
-private:
-    static void sActiveScanHandler(otActiveScanResult *aResult, void *aThreadHelper);
-    void        ActiveScanHandler(otActiveScanResult *aResult);
-
-    static void sJoinerCallback(otError aError, void *aThreadHelper);
-    void        JoinerCallback(otError aResult);
-
-    void    RandomFill(void *aBuf, size_t size);
-    uint8_t RandomChannelFromChannelMask(uint32_t aChannelMask);
-
-    otInstance *mInstance;
-
-    otbr::Ncp::ControllerOpenThread *mNcp;
-
-    ScanHandler                     mScanHandler;
-    std::vector<otActiveScanResult> mScanResults;
-
-    std::vector<DeviceRoleHandler> mDeviceRoleHandlers;
-
-    std::map<uint16_t, size_t> mUnsecurePortRefCounter;
-
-    ResultHandler mAttachHandler;
-    ResultHandler mJoinerHandler;
-
-    std::random_device mRandomDevice;
-};
-
-} // namespace agent
-} // namespace otbr
-
-#endif // OTBR_THREAD_HELPER_HPP_