src/controller/SetUpCodePairer.cpp - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2021 Project CHIP Authors
  *    All rights reserved.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
  *    You may obtain a copy of the License at
  *
  *        http://www.apache.org/licenses/LICENSE-2.0
  *
  *    Unless required by applicable law or agreed to in writing, software
  *    distributed under the License is distributed on an "AS IS" BASIS,
  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */

 /**
  *    @file
  *      Implementation of SetUp Code Pairer, a class that parses a given
  *      setup code and uses the extracted informations to discover and
  *      filter commissionables nodes, before initiating the pairing process.
  *
  */

 #include <controller/SetUpCodePairer.h>

 #include <controller/CHIPDeviceController.h>
 #include <lib/dnssd/Resolver.h>
 #include <lib/support/CodeUtils.h>
 #include <system/SystemClock.h>

 constexpr uint32_t kDeviceDiscoveredTimeout = CHIP_CONFIG_SETUP_CODE_PAIRER_DISCOVERY_TIMEOUT_SECS * chip::kMillisecondsPerSecond;

 namespace chip {
 namespace Controller {

 CHIP_ERROR SetUpCodePairer::PairDevice(NodeId remoteId, const char * setUpCode, SetupCodePairerBehaviour commission,
                                        DiscoveryType discoveryType)
 {
     VerifyOrReturnError(mSystemLayer != nullptr, CHIP_ERROR_INCORRECT_STATE);

     SetupPayload payload;
     mConnectionType = commission;
     mDiscoveryType  = discoveryType;

     bool isQRCode = strncmp(setUpCode, kQRCodePrefix, strlen(kQRCodePrefix)) == 0;
     if (isQRCode)
     {
         ReturnErrorOnFailure(QRCodeSetupPayloadParser(setUpCode).populatePayload(payload));
         VerifyOrReturnError(payload.isValidQRCodePayload(), CHIP_ERROR_INVALID_ARGUMENT);
     }
     else
     {
         ReturnErrorOnFailure(ManualSetupPayloadParser(setUpCode).populatePayload(payload));
         VerifyOrReturnError(payload.isValidManualCode(), CHIP_ERROR_INVALID_ARGUMENT);
     }

     mRemoteId     = remoteId;
     mSetUpPINCode = payload.setUpPINCode;

     ResetDiscoveryState();

     ReturnErrorOnFailure(Connect(payload));

     return mSystemLayer->StartTimer(System::Clock::Milliseconds32(kDeviceDiscoveredTimeout), OnDeviceDiscoveredTimeoutCallback,
                                     this);
 }

 CHIP_ERROR SetUpCodePairer::Connect(SetupPayload & payload)
 {
     CHIP_ERROR err = CHIP_NO_ERROR;
     bool isRunning = false;

     bool searchOverAll = !payload.rendezvousInformation.HasValue();

     if (mDiscoveryType == DiscoveryType::kAll)
     {
         if (searchOverAll || payload.rendezvousInformation.Value().Has(RendezvousInformationFlag::kBLE))
         {
             if (CHIP_NO_ERROR == (err = StartDiscoverOverBle(payload)))
             {
                 isRunning = true;
             }
             VerifyOrReturnError(searchOverAll || CHIP_NO_ERROR == err || CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE == err, err);
         }

         if (searchOverAll || payload.rendezvousInformation.Value().Has(RendezvousInformationFlag::kSoftAP))
         {
             if (CHIP_NO_ERROR == (err = StartDiscoverOverSoftAP(payload)))
             {
                 isRunning = true;
             }
             VerifyOrReturnError(searchOverAll || CHIP_NO_ERROR == err || CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE == err, err);
         }
     }

     // We always want to search on network because any node that has already been commissioned will use on-network regardless of the
     // QR code flag.
     if (CHIP_NO_ERROR == (err = StartDiscoverOverIP(payload)))
     {
         isRunning = true;
     }
     VerifyOrReturnError(searchOverAll || CHIP_NO_ERROR == err, err);

     return isRunning ? CHIP_NO_ERROR : CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
 }

 CHIP_ERROR SetUpCodePairer::StartDiscoverOverBle(SetupPayload & payload)
 {
 #if CONFIG_NETWORK_LAYER_BLE
 #if CHIP_DEVICE_CONFIG_ENABLE_BOTH_COMMISSIONER_AND_COMMISSIONEE
     VerifyOrReturnError(mCommissioner != nullptr, CHIP_ERROR_INCORRECT_STATE);
     mCommissioner->ConnectBleTransportToSelf();
 #endif // CHIP_DEVICE_CONFIG_ENABLE_BOTH_COMMISSIONER_AND_COMMISSIONEE
     VerifyOrReturnError(mBleLayer != nullptr, CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE);

     ChipLogProgress(Controller, "Starting commissioning discovery over BLE");

     // Handle possibly-sync callbacks.
     mWaitingForDiscovery[kBLETransport] = true;
     CHIP_ERROR err = mBleLayer->NewBleConnectionByDiscriminator(payload.discriminator, this, OnDiscoveredDeviceOverBleSuccess,
                                                                 OnDiscoveredDeviceOverBleError);
     if (err != CHIP_NO_ERROR)
     {
         mWaitingForDiscovery[kBLETransport] = false;
     }
     return err;
 #else
     return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
 #endif // CONFIG_NETWORK_LAYER_BLE
 }

 CHIP_ERROR SetUpCodePairer::StopConnectOverBle()
 {
     // Make sure to not call CancelBleIncompleteConnection unless we are in fact
     // waiting on BLE discovery.  It will cancel connections that are in fact
     // completed. In particular, if we just established PASE over BLE calling
     // CancelBleIncompleteConnection here unconditionally would cancel the BLE
     // connection underlying the PASE session.  So make sure to only call
     // CancelBleIncompleteConnection if we're still waiting to hear back on the
     // BLE discovery bits.
     if (!mWaitingForDiscovery[kBLETransport])
     {
         return CHIP_NO_ERROR;
     }

     mWaitingForDiscovery[kBLETransport] = false;
 #if CONFIG_NETWORK_LAYER_BLE
     VerifyOrReturnError(mBleLayer != nullptr, CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE);
     ChipLogDetail(Controller, "Stopping commissioning discovery over BLE");
     return mBleLayer->CancelBleIncompleteConnection();
 #else
     return CHIP_NO_ERROR;
 #endif // CONFIG_NETWORK_LAYER_BLE
 }

 CHIP_ERROR SetUpCodePairer::StartDiscoverOverIP(SetupPayload & payload)
 {
     ChipLogProgress(Controller, "Starting commissioning discovery over DNS-SD");

     auto & discriminator = payload.discriminator;
     if (discriminator.IsShortDiscriminator())
     {
         mCurrentFilter.type = Dnssd::DiscoveryFilterType::kShortDiscriminator;
         mCurrentFilter.code = discriminator.GetShortValue();
     }
     else
     {
         mCurrentFilter.type = Dnssd::DiscoveryFilterType::kLongDiscriminator;
         mCurrentFilter.code = discriminator.GetLongValue();
     }
     mPayloadVendorID  = payload.vendorID;
     mPayloadProductID = payload.productID;

     // Handle possibly-sync callbacks.
     mWaitingForDiscovery[kIPTransport] = true;
     CHIP_ERROR err                     = mCommissioner->DiscoverCommissionableNodes(mCurrentFilter);
     if (err != CHIP_NO_ERROR)
     {
         mWaitingForDiscovery[kIPTransport] = false;
     }
     return err;
 }

 CHIP_ERROR SetUpCodePairer::StopConnectOverIP()
 {
     ChipLogDetail(Controller, "Stopping commissioning discovery over DNS-SD");

     mWaitingForDiscovery[kIPTransport] = false;
     mCurrentFilter.type                = Dnssd::DiscoveryFilterType::kNone;
     mPayloadVendorID                   = kNotAvailable;
     mPayloadProductID                  = kNotAvailable;

     mCommissioner->StopCommissionableDiscovery();
     return CHIP_NO_ERROR;
 }

 CHIP_ERROR SetUpCodePairer::StartDiscoverOverSoftAP(SetupPayload & payload)
 {
     return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
 }

 CHIP_ERROR SetUpCodePairer::StopConnectOverSoftAP()
 {
     mWaitingForDiscovery[kSoftAPTransport] = false;
     return CHIP_NO_ERROR;
 }

 bool SetUpCodePairer::ConnectToDiscoveredDevice()
 {
     if (mWaitingForPASE)
     {
         // Nothing to do.  Just wait until we either succeed or fail at that
         // PASE session establishment.
         return false;
     }

     if (!mDiscoveredParameters.empty())
     {
         // Grab the first element from the queue and try connecting to it.
         // Remove it from the queue before we try to connect, in case the
         // connection attempt fails and calls right back into us to try the next
         // thing.
         SetUpCodePairerParameters params(mDiscoveredParameters.front());
         mDiscoveredParameters.pop_front();

         params.SetSetupPINCode(mSetUpPINCode);

 #if CHIP_PROGRESS_LOGGING
         char buf[Transport::PeerAddress::kMaxToStringSize];
         params.GetPeerAddress().ToString(buf);
         ChipLogProgress(Controller, "Attempting PASE connection to %s", buf);
 #endif // CHIP_PROGRESS_LOGGING

         // Handle possibly-sync call backs from attempts to establish PASE.
         ExpectPASEEstablishment();

         if (params.GetPeerAddress().GetTransportType() == Transport::Type::kUdp)
         {
             mCurrentPASEParameters.SetValue(params);
         }

         CHIP_ERROR err;
         if (mConnectionType == SetupCodePairerBehaviour::kCommission)
         {
             err = mCommissioner->PairDevice(mRemoteId, params);
         }
         else
         {
             err = mCommissioner->EstablishPASEConnection(mRemoteId, params);
         }

         LogErrorOnFailure(err);
         if (err == CHIP_NO_ERROR)
         {
             return true;
         }

         // Failed to start establishing PASE.
         PASEEstablishmentComplete();
     }

     return false;
 }

 #if CONFIG_NETWORK_LAYER_BLE
 void SetUpCodePairer::OnDiscoveredDeviceOverBle(BLE_CONNECTION_OBJECT connObj)
 {
     ChipLogProgress(Controller, "Discovered device to be commissioned over BLE");

     mWaitingForDiscovery[kBLETransport] = false;

     // In order to not wait for all the possible addresses discovered over mdns to
     // be tried before trying to connect over BLE, the discovered connection object is
     // inserted at the beginning of the list.
     //
     // It makes it the 'next' thing to try to connect to if there are already some
     // discovered parameters in the list.
     mDiscoveredParameters.emplace_front(connObj);
     ConnectToDiscoveredDevice();
 }

 void SetUpCodePairer::OnDiscoveredDeviceOverBleSuccess(void * appState, BLE_CONNECTION_OBJECT connObj)
 {
     (static_cast<SetUpCodePairer *>(appState))->OnDiscoveredDeviceOverBle(connObj);
 }

 void SetUpCodePairer::OnDiscoveredDeviceOverBleError(void * appState, CHIP_ERROR err)
 {
     static_cast<SetUpCodePairer *>(appState)->OnBLEDiscoveryError(err);
 }

 void SetUpCodePairer::OnBLEDiscoveryError(CHIP_ERROR err)
 {
     ChipLogError(Controller, "Commissioning discovery over BLE failed: %" CHIP_ERROR_FORMAT, err.Format());
     mWaitingForDiscovery[kBLETransport] = false;
     LogErrorOnFailure(err);
 }
 #endif // CONFIG_NETWORK_LAYER_BLE

 bool SetUpCodePairer::IdIsPresent(uint16_t vendorOrProductID)
 {
     return vendorOrProductID != kNotAvailable;
 }

 bool SetUpCodePairer::NodeMatchesCurrentFilter(const Dnssd::DiscoveredNodeData & nodeData) const
 {
     if (nodeData.commissionData.commissioningMode == 0)
     {
         return false;
     }

     // The advertisement may not include a vendor id.
     if (IdIsPresent(mPayloadVendorID) && IdIsPresent(nodeData.commissionData.vendorId) &&
         mPayloadVendorID != nodeData.commissionData.vendorId)
     {
         return false;
     }

     // The advertisement may not include a product id.
     if (IdIsPresent(mPayloadProductID) && IdIsPresent(nodeData.commissionData.productId) &&
         mPayloadProductID != nodeData.commissionData.productId)
     {
         return false;
     }

     switch (mCurrentFilter.type)
     {
     case Dnssd::DiscoveryFilterType::kShortDiscriminator:
         return ((nodeData.commissionData.longDiscriminator >> 8) & 0x0F) == mCurrentFilter.code;
     case Dnssd::DiscoveryFilterType::kLongDiscriminator:
         return nodeData.commissionData.longDiscriminator == mCurrentFilter.code;
     default:
         return false;
     }
     return false;
 }

 void SetUpCodePairer::NotifyCommissionableDeviceDiscovered(const Dnssd::DiscoveredNodeData & nodeData)
 {
     if (!NodeMatchesCurrentFilter(nodeData))
     {
         return;
     }

     ChipLogProgress(Controller, "Discovered device to be commissioned over DNS-SD");

     auto & resolutionData = nodeData.resolutionData;
     for (size_t i = 0; i < resolutionData.numIPs; i++)
     {
         mDiscoveredParameters.emplace_back(nodeData.resolutionData, i);
     }

     ConnectToDiscoveredDevice();
 }

 void SetUpCodePairer::CommissionerShuttingDown()
 {
     ResetDiscoveryState();
 }

 bool SetUpCodePairer::TryNextRendezvousParameters()
 {
     if (ConnectToDiscoveredDevice())
     {
         ChipLogProgress(Controller, "Trying connection to commissionee over different transport");
         return true;
     }

     if (DiscoveryInProgress())
     {
         ChipLogProgress(Controller, "Waiting to discover commissionees that match our filters");
         return true;
     }

     return false;
 }

 bool SetUpCodePairer::DiscoveryInProgress() const
 {
     for (const auto & waiting : mWaitingForDiscovery)
     {
         if (waiting)
         {
             return true;
         }
     }

     return false;
 }

 void SetUpCodePairer::ResetDiscoveryState()
 {
     StopConnectOverBle();
     StopConnectOverIP();
     StopConnectOverSoftAP();

     // Just in case any of those failed to reset the waiting state properly.
     for (auto & waiting : mWaitingForDiscovery)
     {
         waiting = false;
     }

     while (!mDiscoveredParameters.empty())
     {
         mDiscoveredParameters.pop_front();
     }

     mCurrentPASEParameters.ClearValue();
     mLastPASEError = CHIP_NO_ERROR;
 }

 void SetUpCodePairer::ExpectPASEEstablishment()
 {
     mWaitingForPASE = true;
     auto * delegate = mCommissioner->GetPairingDelegate();
     if (this == delegate)
     {
         // This should really not happen, but if it does, do nothing, to avoid
         // delegate loops.
         return;
     }

     mPairingDelegate = delegate;
     mCommissioner->RegisterPairingDelegate(this);
 }

 void SetUpCodePairer::PASEEstablishmentComplete()
 {
     mWaitingForPASE = false;
     mCommissioner->RegisterPairingDelegate(mPairingDelegate);
     mPairingDelegate = nullptr;
 }

 void SetUpCodePairer::OnStatusUpdate(DevicePairingDelegate::Status status)
 {
     if (status == DevicePairingDelegate::Status::SecurePairingFailed)
     {
         // If we're still waiting on discovery, don't propagate this failure
         // (which is due to PASE failure with something we discovered, but the
         // "something" may not have been the right thing) for now.  Wait until
         // discovery completes.  Then we will either succeed and notify
         // accordingly or time out and land in OnStatusUpdate again, but at that
         // point we will not be waiting on discovery anymore.
         if (!mDiscoveredParameters.empty())
         {
             ChipLogProgress(Controller, "Ignoring SecurePairingFailed status for now; we have more discovered devices to try");
             status = DevicePairingDelegate::Status::SecurePairingDiscoveringMoreDevices;
         }

         if (DiscoveryInProgress())
         {
             ChipLogProgress(Controller,
                             "Ignoring SecurePairingFailed status for now; we are waiting to see if we discover more devices");
             status = DevicePairingDelegate::Status::SecurePairingDiscoveringMoreDevices;
         }
     }

     if (mPairingDelegate)
     {
         mPairingDelegate->OnStatusUpdate(status);
     }
 }

 void SetUpCodePairer::OnPairingComplete(CHIP_ERROR error)
 {
     // Save the pairing delegate so we can notify it.  We want to notify it
     // _after_ we restore the state on the commissioner, in case the delegate
     // ends up immediately calling back into the commissioner again when
     // notified.
     auto * pairingDelegate = mPairingDelegate;
     PASEEstablishmentComplete();

     if (CHIP_NO_ERROR == error)
     {
         mSystemLayer->CancelTimer(OnDeviceDiscoveredTimeoutCallback, this);

         ResetDiscoveryState();
         if (pairingDelegate != nullptr)
         {
             pairingDelegate->OnPairingComplete(error);
         }
         return;
     }

     // It may happen that there is a stale DNS entry. If so, ReconfirmRecord will flush
     // the record from the daemon cache once it determines that it is invalid.
     // It may not help for this particular resolve, but may help subsequent resolves.
     if (CHIP_ERROR_TIMEOUT == error && mCurrentPASEParameters.HasValue())
     {
         const auto & params = mCurrentPASEParameters.Value();
         const auto & peer   = params.GetPeerAddress();
         const auto & ip     = peer.GetIPAddress();
         auto err            = Dnssd::Resolver::Instance().ReconfirmRecord(params.mHostName, ip, params.mInterfaceId);
         if (CHIP_NO_ERROR != err && CHIP_ERROR_NOT_IMPLEMENTED != err)
         {
             ChipLogError(Controller, "Error when verifying the validity of an address: %" CHIP_ERROR_FORMAT, err.Format());
         }
     }
     mCurrentPASEParameters.ClearValue();

     // We failed to establish PASE.  Try the next thing we have discovered, if
     // any.
     if (TryNextRendezvousParameters())
     {
         // Keep waiting until that finishes.  Don't call OnPairingComplete yet.
         mLastPASEError = error;
         return;
     }

     if (pairingDelegate != nullptr)
     {
         pairingDelegate->OnPairingComplete(error);
     }
 }

 void SetUpCodePairer::OnPairingDeleted(CHIP_ERROR error)
 {
     if (mPairingDelegate)
     {
         mPairingDelegate->OnPairingDeleted(error);
     }
 }

 void SetUpCodePairer::OnCommissioningComplete(NodeId deviceId, CHIP_ERROR error)
 {
     // Not really expecting this, but handle it anyway.
     if (mPairingDelegate)
     {
         mPairingDelegate->OnCommissioningComplete(deviceId, error);
     }
 }

 void SetUpCodePairer::OnDeviceDiscoveredTimeoutCallback(System::Layer * layer, void * context)
 {
     ChipLogError(Controller, "Discovery timed out");
     auto * pairer = static_cast<SetUpCodePairer *>(context);
     LogErrorOnFailure(pairer->StopConnectOverBle());
     LogErrorOnFailure(pairer->StopConnectOverIP());
     LogErrorOnFailure(pairer->StopConnectOverSoftAP());
     if (!pairer->mWaitingForPASE && pairer->mDiscoveredParameters.empty())
     {
         // We're not waiting on any more PASE attempts, and we're not going to
         // discover anything at this point, so we should just notify our
         // listener.
         CHIP_ERROR err = pairer->mLastPASEError;
         if (err == CHIP_NO_ERROR)
         {
             err = CHIP_ERROR_TIMEOUT;
         }
         pairer->mCommissioner->OnSessionEstablishmentError(err);
     }
 }

 SetUpCodePairerParameters::SetUpCodePairerParameters(const Dnssd::CommonResolutionData & data, size_t index)
 {
     mInterfaceId = data.interfaceId;
     Platform::CopyString(mHostName, data.hostName);

     auto & ip = data.ipAddress[index];
     SetPeerAddress(Transport::PeerAddress::UDP(ip, data.port, ip.IsIPv6LinkLocal() ? data.interfaceId : Inet::InterfaceId::Null()));

     if (data.mrpRetryIntervalIdle.HasValue())
     {
         SetIdleInterval(data.mrpRetryIntervalIdle.Value());
     }

     if (data.mrpRetryIntervalActive.HasValue())
     {
         SetActiveInterval(data.mrpRetryIntervalActive.Value());
     }
 }

 #if CONFIG_NETWORK_LAYER_BLE
 SetUpCodePairerParameters::SetUpCodePairerParameters(BLE_CONNECTION_OBJECT connObj)
 {
     Transport::PeerAddress peerAddress = Transport::PeerAddress::BLE();
     SetPeerAddress(peerAddress).SetConnectionObject(connObj);
 }
 #endif // CONFIG_NETWORK_LAYER_BLE

 } // namespace Controller
 } // namespace chip
	/*
	*
	* Copyright (c) 2021 Project CHIP Authors
	* All rights reserved.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/**
	* @file
	* Implementation of SetUp Code Pairer, a class that parses a given
	* setup code and uses the extracted informations to discover and
	* filter commissionables nodes, before initiating the pairing process.
	*
	*/

	#include <controller/SetUpCodePairer.h>

	#include <controller/CHIPDeviceController.h>
	#include <lib/dnssd/Resolver.h>
	#include <lib/support/CodeUtils.h>
	#include <system/SystemClock.h>

	constexpr uint32_t kDeviceDiscoveredTimeout = CHIP_CONFIG_SETUP_CODE_PAIRER_DISCOVERY_TIMEOUT_SECS * chip::kMillisecondsPerSecond;

	namespace chip {
	namespace Controller {

	CHIP_ERROR SetUpCodePairer::PairDevice(NodeId remoteId, const char * setUpCode, SetupCodePairerBehaviour commission,
	DiscoveryType discoveryType)
	{
	VerifyOrReturnError(mSystemLayer != nullptr, CHIP_ERROR_INCORRECT_STATE);

	SetupPayload payload;
	mConnectionType = commission;
	mDiscoveryType = discoveryType;

	bool isQRCode = strncmp(setUpCode, kQRCodePrefix, strlen(kQRCodePrefix)) == 0;
	if (isQRCode)
	{
	ReturnErrorOnFailure(QRCodeSetupPayloadParser(setUpCode).populatePayload(payload));
	VerifyOrReturnError(payload.isValidQRCodePayload(), CHIP_ERROR_INVALID_ARGUMENT);
	}
	else
	{
	ReturnErrorOnFailure(ManualSetupPayloadParser(setUpCode).populatePayload(payload));
	VerifyOrReturnError(payload.isValidManualCode(), CHIP_ERROR_INVALID_ARGUMENT);
	}

	mRemoteId = remoteId;
	mSetUpPINCode = payload.setUpPINCode;

	ResetDiscoveryState();

	ReturnErrorOnFailure(Connect(payload));

	return mSystemLayer->StartTimer(System::Clock::Milliseconds32(kDeviceDiscoveredTimeout), OnDeviceDiscoveredTimeoutCallback,
	this);
	}

	CHIP_ERROR SetUpCodePairer::Connect(SetupPayload & payload)
	{
	CHIP_ERROR err = CHIP_NO_ERROR;
	bool isRunning = false;

	bool searchOverAll = !payload.rendezvousInformation.HasValue();

	if (mDiscoveryType == DiscoveryType::kAll)
	{
	if (searchOverAll \|\| payload.rendezvousInformation.Value().Has(RendezvousInformationFlag::kBLE))
	{
	if (CHIP_NO_ERROR == (err = StartDiscoverOverBle(payload)))
	{
	isRunning = true;
	}
	VerifyOrReturnError(searchOverAll \|\| CHIP_NO_ERROR == err \|\| CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE == err, err);
	}

	if (searchOverAll \|\| payload.rendezvousInformation.Value().Has(RendezvousInformationFlag::kSoftAP))
	{
	if (CHIP_NO_ERROR == (err = StartDiscoverOverSoftAP(payload)))
	{
	isRunning = true;
	}
	VerifyOrReturnError(searchOverAll \|\| CHIP_NO_ERROR == err \|\| CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE == err, err);
	}
	}

	// We always want to search on network because any node that has already been commissioned will use on-network regardless of the
	// QR code flag.
	if (CHIP_NO_ERROR == (err = StartDiscoverOverIP(payload)))
	{
	isRunning = true;
	}
	VerifyOrReturnError(searchOverAll \|\| CHIP_NO_ERROR == err, err);

	return isRunning ? CHIP_NO_ERROR : CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
	}

	CHIP_ERROR SetUpCodePairer::StartDiscoverOverBle(SetupPayload & payload)
	{
	#if CONFIG_NETWORK_LAYER_BLE
	#if CHIP_DEVICE_CONFIG_ENABLE_BOTH_COMMISSIONER_AND_COMMISSIONEE
	VerifyOrReturnError(mCommissioner != nullptr, CHIP_ERROR_INCORRECT_STATE);
	mCommissioner->ConnectBleTransportToSelf();
	#endif // CHIP_DEVICE_CONFIG_ENABLE_BOTH_COMMISSIONER_AND_COMMISSIONEE
	VerifyOrReturnError(mBleLayer != nullptr, CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE);

	ChipLogProgress(Controller, "Starting commissioning discovery over BLE");

	// Handle possibly-sync callbacks.
	mWaitingForDiscovery[kBLETransport] = true;
	CHIP_ERROR err = mBleLayer->NewBleConnectionByDiscriminator(payload.discriminator, this, OnDiscoveredDeviceOverBleSuccess,
	OnDiscoveredDeviceOverBleError);
	if (err != CHIP_NO_ERROR)
	{
	mWaitingForDiscovery[kBLETransport] = false;
	}
	return err;
	#else
	return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
	#endif // CONFIG_NETWORK_LAYER_BLE
	}

	CHIP_ERROR SetUpCodePairer::StopConnectOverBle()
	{
	// Make sure to not call CancelBleIncompleteConnection unless we are in fact
	// waiting on BLE discovery. It will cancel connections that are in fact
	// completed. In particular, if we just established PASE over BLE calling
	// CancelBleIncompleteConnection here unconditionally would cancel the BLE
	// connection underlying the PASE session. So make sure to only call
	// CancelBleIncompleteConnection if we're still waiting to hear back on the
	// BLE discovery bits.
	if (!mWaitingForDiscovery[kBLETransport])
	{
	return CHIP_NO_ERROR;
	}

	mWaitingForDiscovery[kBLETransport] = false;
	#if CONFIG_NETWORK_LAYER_BLE
	VerifyOrReturnError(mBleLayer != nullptr, CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE);
	ChipLogDetail(Controller, "Stopping commissioning discovery over BLE");
	return mBleLayer->CancelBleIncompleteConnection();
	#else
	return CHIP_NO_ERROR;
	#endif // CONFIG_NETWORK_LAYER_BLE
	}

	CHIP_ERROR SetUpCodePairer::StartDiscoverOverIP(SetupPayload & payload)
	{
	ChipLogProgress(Controller, "Starting commissioning discovery over DNS-SD");

	auto & discriminator = payload.discriminator;
	if (discriminator.IsShortDiscriminator())
	{
	mCurrentFilter.type = Dnssd::DiscoveryFilterType::kShortDiscriminator;
	mCurrentFilter.code = discriminator.GetShortValue();
	}
	else
	{
	mCurrentFilter.type = Dnssd::DiscoveryFilterType::kLongDiscriminator;
	mCurrentFilter.code = discriminator.GetLongValue();
	}
	mPayloadVendorID = payload.vendorID;
	mPayloadProductID = payload.productID;

	// Handle possibly-sync callbacks.
	mWaitingForDiscovery[kIPTransport] = true;
	CHIP_ERROR err = mCommissioner->DiscoverCommissionableNodes(mCurrentFilter);
	if (err != CHIP_NO_ERROR)
	{
	mWaitingForDiscovery[kIPTransport] = false;
	}
	return err;
	}

	CHIP_ERROR SetUpCodePairer::StopConnectOverIP()
	{
	ChipLogDetail(Controller, "Stopping commissioning discovery over DNS-SD");

	mWaitingForDiscovery[kIPTransport] = false;
	mCurrentFilter.type = Dnssd::DiscoveryFilterType::kNone;
	mPayloadVendorID = kNotAvailable;
	mPayloadProductID = kNotAvailable;

	mCommissioner->StopCommissionableDiscovery();
	return CHIP_NO_ERROR;
	}

	CHIP_ERROR SetUpCodePairer::StartDiscoverOverSoftAP(SetupPayload & payload)
	{
	return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
	}

	CHIP_ERROR SetUpCodePairer::StopConnectOverSoftAP()
	{
	mWaitingForDiscovery[kSoftAPTransport] = false;
	return CHIP_NO_ERROR;
	}

	bool SetUpCodePairer::ConnectToDiscoveredDevice()
	{
	if (mWaitingForPASE)
	{
	// Nothing to do. Just wait until we either succeed or fail at that
	// PASE session establishment.
	return false;
	}

	if (!mDiscoveredParameters.empty())
	{
	// Grab the first element from the queue and try connecting to it.
	// Remove it from the queue before we try to connect, in case the
	// connection attempt fails and calls right back into us to try the next
	// thing.
	SetUpCodePairerParameters params(mDiscoveredParameters.front());
	mDiscoveredParameters.pop_front();

	params.SetSetupPINCode(mSetUpPINCode);

	#if CHIP_PROGRESS_LOGGING
	char buf[Transport::PeerAddress::kMaxToStringSize];
	params.GetPeerAddress().ToString(buf);
	ChipLogProgress(Controller, "Attempting PASE connection to %s", buf);
	#endif // CHIP_PROGRESS_LOGGING

	// Handle possibly-sync call backs from attempts to establish PASE.
	ExpectPASEEstablishment();

	if (params.GetPeerAddress().GetTransportType() == Transport::Type::kUdp)
	{
	mCurrentPASEParameters.SetValue(params);
	}

	CHIP_ERROR err;
	if (mConnectionType == SetupCodePairerBehaviour::kCommission)
	{
	err = mCommissioner->PairDevice(mRemoteId, params);
	}
	else
	{
	err = mCommissioner->EstablishPASEConnection(mRemoteId, params);
	}

	LogErrorOnFailure(err);
	if (err == CHIP_NO_ERROR)
	{
	return true;
	}

	// Failed to start establishing PASE.
	PASEEstablishmentComplete();
	}

	return false;
	}

	#if CONFIG_NETWORK_LAYER_BLE
	void SetUpCodePairer::OnDiscoveredDeviceOverBle(BLE_CONNECTION_OBJECT connObj)
	{
	ChipLogProgress(Controller, "Discovered device to be commissioned over BLE");

	mWaitingForDiscovery[kBLETransport] = false;

	// In order to not wait for all the possible addresses discovered over mdns to
	// be tried before trying to connect over BLE, the discovered connection object is
	// inserted at the beginning of the list.
	//
	// It makes it the 'next' thing to try to connect to if there are already some
	// discovered parameters in the list.
	mDiscoveredParameters.emplace_front(connObj);
	ConnectToDiscoveredDevice();
	}

	void SetUpCodePairer::OnDiscoveredDeviceOverBleSuccess(void * appState, BLE_CONNECTION_OBJECT connObj)
	{
	(static_cast<SetUpCodePairer *>(appState))->OnDiscoveredDeviceOverBle(connObj);
	}

	void SetUpCodePairer::OnDiscoveredDeviceOverBleError(void * appState, CHIP_ERROR err)
	{
	static_cast<SetUpCodePairer *>(appState)->OnBLEDiscoveryError(err);
	}

	void SetUpCodePairer::OnBLEDiscoveryError(CHIP_ERROR err)
	{
	ChipLogError(Controller, "Commissioning discovery over BLE failed: %" CHIP_ERROR_FORMAT, err.Format());
	mWaitingForDiscovery[kBLETransport] = false;
	LogErrorOnFailure(err);
	}
	#endif // CONFIG_NETWORK_LAYER_BLE

	bool SetUpCodePairer::IdIsPresent(uint16_t vendorOrProductID)
	{
	return vendorOrProductID != kNotAvailable;
	}

	bool SetUpCodePairer::NodeMatchesCurrentFilter(const Dnssd::DiscoveredNodeData & nodeData) const
	{
	if (nodeData.commissionData.commissioningMode == 0)
	{
	return false;
	}

	// The advertisement may not include a vendor id.
	if (IdIsPresent(mPayloadVendorID) && IdIsPresent(nodeData.commissionData.vendorId) &&
	mPayloadVendorID != nodeData.commissionData.vendorId)
	{
	return false;
	}

	// The advertisement may not include a product id.
	if (IdIsPresent(mPayloadProductID) && IdIsPresent(nodeData.commissionData.productId) &&
	mPayloadProductID != nodeData.commissionData.productId)
	{
	return false;
	}

	switch (mCurrentFilter.type)
	{
	case Dnssd::DiscoveryFilterType::kShortDiscriminator:
	return ((nodeData.commissionData.longDiscriminator >> 8) & 0x0F) == mCurrentFilter.code;
	case Dnssd::DiscoveryFilterType::kLongDiscriminator:
	return nodeData.commissionData.longDiscriminator == mCurrentFilter.code;
	default:
	return false;
	}
	return false;
	}

	void SetUpCodePairer::NotifyCommissionableDeviceDiscovered(const Dnssd::DiscoveredNodeData & nodeData)
	{
	if (!NodeMatchesCurrentFilter(nodeData))
	{
	return;
	}

	ChipLogProgress(Controller, "Discovered device to be commissioned over DNS-SD");

	auto & resolutionData = nodeData.resolutionData;
	for (size_t i = 0; i < resolutionData.numIPs; i++)
	{
	mDiscoveredParameters.emplace_back(nodeData.resolutionData, i);
	}

	ConnectToDiscoveredDevice();
	}

	void SetUpCodePairer::CommissionerShuttingDown()
	{
	ResetDiscoveryState();
	}

	bool SetUpCodePairer::TryNextRendezvousParameters()
	{
	if (ConnectToDiscoveredDevice())
	{
	ChipLogProgress(Controller, "Trying connection to commissionee over different transport");
	return true;
	}

	if (DiscoveryInProgress())
	{
	ChipLogProgress(Controller, "Waiting to discover commissionees that match our filters");
	return true;
	}

	return false;
	}

	bool SetUpCodePairer::DiscoveryInProgress() const
	{
	for (const auto & waiting : mWaitingForDiscovery)
	{
	if (waiting)
	{
	return true;
	}
	}

	return false;
	}

	void SetUpCodePairer::ResetDiscoveryState()
	{
	StopConnectOverBle();
	StopConnectOverIP();
	StopConnectOverSoftAP();

	// Just in case any of those failed to reset the waiting state properly.
	for (auto & waiting : mWaitingForDiscovery)
	{
	waiting = false;
	}

	while (!mDiscoveredParameters.empty())
	{
	mDiscoveredParameters.pop_front();
	}

	mCurrentPASEParameters.ClearValue();
	mLastPASEError = CHIP_NO_ERROR;
	}

	void SetUpCodePairer::ExpectPASEEstablishment()
	{
	mWaitingForPASE = true;
	auto * delegate = mCommissioner->GetPairingDelegate();
	if (this == delegate)
	{
	// This should really not happen, but if it does, do nothing, to avoid
	// delegate loops.
	return;
	}

	mPairingDelegate = delegate;
	mCommissioner->RegisterPairingDelegate(this);
	}

	void SetUpCodePairer::PASEEstablishmentComplete()
	{
	mWaitingForPASE = false;
	mCommissioner->RegisterPairingDelegate(mPairingDelegate);
	mPairingDelegate = nullptr;
	}

	void SetUpCodePairer::OnStatusUpdate(DevicePairingDelegate::Status status)
	{
	if (status == DevicePairingDelegate::Status::SecurePairingFailed)
	{
	// If we're still waiting on discovery, don't propagate this failure
	// (which is due to PASE failure with something we discovered, but the
	// "something" may not have been the right thing) for now. Wait until
	// discovery completes. Then we will either succeed and notify
	// accordingly or time out and land in OnStatusUpdate again, but at that
	// point we will not be waiting on discovery anymore.
	if (!mDiscoveredParameters.empty())
	{
	ChipLogProgress(Controller, "Ignoring SecurePairingFailed status for now; we have more discovered devices to try");
	status = DevicePairingDelegate::Status::SecurePairingDiscoveringMoreDevices;
	}

	if (DiscoveryInProgress())
	{
	ChipLogProgress(Controller,
	"Ignoring SecurePairingFailed status for now; we are waiting to see if we discover more devices");
	status = DevicePairingDelegate::Status::SecurePairingDiscoveringMoreDevices;
	}
	}

	if (mPairingDelegate)
	{
	mPairingDelegate->OnStatusUpdate(status);
	}
	}

	void SetUpCodePairer::OnPairingComplete(CHIP_ERROR error)
	{
	// Save the pairing delegate so we can notify it. We want to notify it
	// _after_ we restore the state on the commissioner, in case the delegate
	// ends up immediately calling back into the commissioner again when
	// notified.
	auto * pairingDelegate = mPairingDelegate;
	PASEEstablishmentComplete();

	if (CHIP_NO_ERROR == error)
	{
	mSystemLayer->CancelTimer(OnDeviceDiscoveredTimeoutCallback, this);

	ResetDiscoveryState();
	if (pairingDelegate != nullptr)
	{
	pairingDelegate->OnPairingComplete(error);
	}
	return;
	}

	// It may happen that there is a stale DNS entry. If so, ReconfirmRecord will flush
	// the record from the daemon cache once it determines that it is invalid.
	// It may not help for this particular resolve, but may help subsequent resolves.
	if (CHIP_ERROR_TIMEOUT == error && mCurrentPASEParameters.HasValue())
	{
	const auto & params = mCurrentPASEParameters.Value();
	const auto & peer = params.GetPeerAddress();
	const auto & ip = peer.GetIPAddress();
	auto err = Dnssd::Resolver::Instance().ReconfirmRecord(params.mHostName, ip, params.mInterfaceId);
	if (CHIP_NO_ERROR != err && CHIP_ERROR_NOT_IMPLEMENTED != err)
	{
	ChipLogError(Controller, "Error when verifying the validity of an address: %" CHIP_ERROR_FORMAT, err.Format());
	}
	}
	mCurrentPASEParameters.ClearValue();

	// We failed to establish PASE. Try the next thing we have discovered, if
	// any.
	if (TryNextRendezvousParameters())
	{
	// Keep waiting until that finishes. Don't call OnPairingComplete yet.
	mLastPASEError = error;
	return;
	}

	if (pairingDelegate != nullptr)
	{
	pairingDelegate->OnPairingComplete(error);
	}
	}

	void SetUpCodePairer::OnPairingDeleted(CHIP_ERROR error)
	{
	if (mPairingDelegate)
	{
	mPairingDelegate->OnPairingDeleted(error);
	}
	}

	void SetUpCodePairer::OnCommissioningComplete(NodeId deviceId, CHIP_ERROR error)
	{
	// Not really expecting this, but handle it anyway.
	if (mPairingDelegate)
	{
	mPairingDelegate->OnCommissioningComplete(deviceId, error);
	}
	}

	void SetUpCodePairer::OnDeviceDiscoveredTimeoutCallback(System::Layer * layer, void * context)
	{
	ChipLogError(Controller, "Discovery timed out");
	auto * pairer = static_cast<SetUpCodePairer *>(context);
	LogErrorOnFailure(pairer->StopConnectOverBle());
	LogErrorOnFailure(pairer->StopConnectOverIP());
	LogErrorOnFailure(pairer->StopConnectOverSoftAP());
	if (!pairer->mWaitingForPASE && pairer->mDiscoveredParameters.empty())
	{
	// We're not waiting on any more PASE attempts, and we're not going to
	// discover anything at this point, so we should just notify our
	// listener.
	CHIP_ERROR err = pairer->mLastPASEError;
	if (err == CHIP_NO_ERROR)
	{
	err = CHIP_ERROR_TIMEOUT;
	}
	pairer->mCommissioner->OnSessionEstablishmentError(err);
	}
	}

	SetUpCodePairerParameters::SetUpCodePairerParameters(const Dnssd::CommonResolutionData & data, size_t index)
	{
	mInterfaceId = data.interfaceId;
	Platform::CopyString(mHostName, data.hostName);

	auto & ip = data.ipAddress[index];
	SetPeerAddress(Transport::PeerAddress::UDP(ip, data.port, ip.IsIPv6LinkLocal() ? data.interfaceId : Inet::InterfaceId::Null()));

	if (data.mrpRetryIntervalIdle.HasValue())
	{
	SetIdleInterval(data.mrpRetryIntervalIdle.Value());
	}

	if (data.mrpRetryIntervalActive.HasValue())
	{
	SetActiveInterval(data.mrpRetryIntervalActive.Value());
	}
	}

	#if CONFIG_NETWORK_LAYER_BLE
	SetUpCodePairerParameters::SetUpCodePairerParameters(BLE_CONNECTION_OBJECT connObj)
	{
	Transport::PeerAddress peerAddress = Transport::PeerAddress::BLE();
	SetPeerAddress(peerAddress).SetConnectionObject(connObj);
	}
	#endif // CONFIG_NETWORK_LAYER_BLE

	} // namespace Controller
	} // namespace chip