src/messaging/ExchangeMgr.cpp - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2020 Project CHIP Authors
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
  *    You may obtain a copy of the License at
  *
  *        http://www.apache.org/licenses/LICENSE-2.0
  *
  *    Unless required by applicable law or agreed to in writing, software
  *    distributed under the License is distributed on an "AS IS" BASIS,
  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */

 /**
  *    @file
  *      This file implements the ExchangeManager class.
  *
  */

 #ifndef __STDC_FORMAT_MACROS
 #define __STDC_FORMAT_MACROS
 #endif

 #ifndef __STDC_LIMIT_MACROS
 #define __STDC_LIMIT_MACROS
 #endif

 #include <cstring>
 #include <inttypes.h>
 #include <stddef.h>

 #include <core/CHIPCore.h>
 #include <core/CHIPEncoding.h>
 #include <messaging/ExchangeContext.h>
 #include <messaging/ExchangeMgr.h>
 #include <support/CHIPFaultInjection.h>
 #include <support/CodeUtils.h>
 #include <support/RandUtils.h>
 #include <support/logging/CHIPLogging.h>

 using namespace chip::Encoding;
 using namespace chip::Inet;
 using namespace chip::System;

 namespace chip {

 /**
  *  Constructor for the ExchangeManager class.
  *  It sets the state to kState_NotInitialized.
  *
  *  @note
  *    The class must be initialized via ExchangeManager::Init()
  *    prior to use.
  *
  */
 ExchangeManager::ExchangeManager()
 {
     mState = State::kState_NotInitialized;
 }

 CHIP_ERROR ExchangeManager::Init(SecureSessionMgr * sessionMgr)
 {
     if (mState != State::kState_NotInitialized)
         return CHIP_ERROR_INCORRECT_STATE;

     mSessionMgr = sessionMgr;

     mNextExchangeId = GetRandU16();

     mContextsInUse = 0;

     memset(UMHandlerPool, 0, sizeof(UMHandlerPool));
     OnExchangeContextChanged = nullptr;

     sessionMgr->SetDelegate(this);

     mState = State::kState_Initialized;

     return CHIP_NO_ERROR;
 }

 CHIP_ERROR ExchangeManager::Shutdown()
 {
     if (mSessionMgr != nullptr)
     {
         mSessionMgr->SetDelegate(nullptr);
         mSessionMgr = nullptr;
     }

     OnExchangeContextChanged = nullptr;

     mState = State::kState_NotInitialized;

     return CHIP_NO_ERROR;
 }

 ExchangeContext * ExchangeManager::NewContext(const NodeId & peerNodeId, ExchangeDelegate * delegate)
 {
     return AllocContext(mNextExchangeId++, peerNodeId, true, delegate);
 }

 ExchangeContext * ExchangeManager::FindContext(NodeId peerNodeId, ExchangeDelegate * delegate, bool isInitiator)
 {
     for (auto & ec : ContextPool)
     {
         if (ec.GetReferenceCount() > 0 && ec.GetPeerNodeId() == peerNodeId && ec.GetDelegate() == delegate &&
             ec.IsInitiator() == isInitiator)
             return &ec;
     }

     return nullptr;
 }

 CHIP_ERROR ExchangeManager::RegisterUnsolicitedMessageHandler(uint32_t protocolId, ExchangeDelegate * delegate)
 {
     return RegisterUMH(protocolId, kAnyMessageType, delegate);
 }

 CHIP_ERROR ExchangeManager::RegisterUnsolicitedMessageHandler(uint32_t protocolId, uint8_t msgType, ExchangeDelegate * delegate)
 {
     return RegisterUMH(protocolId, static_cast<int16_t>(msgType), delegate);
 }

 CHIP_ERROR ExchangeManager::UnregisterUnsolicitedMessageHandler(uint32_t protocolId)
 {
     return UnregisterUMH(protocolId, kAnyMessageType);
 }

 CHIP_ERROR ExchangeManager::UnregisterUnsolicitedMessageHandler(uint32_t protocolId, uint8_t msgType)
 {
     return UnregisterUMH(protocolId, static_cast<int16_t>(msgType));
 }

 void ExchangeManager::OnReceiveError(CHIP_ERROR error, const Transport::PeerAddress & source, SecureSessionMgr * msgLayer)
 {
     ChipLogError(ExchangeManager, "Accept FAILED, err = %s", ErrorStr(error));
 }

 ExchangeContext * ExchangeManager::AllocContext(uint16_t ExchangeId, uint64_t PeerNodeId, bool Initiator,
                                                 ExchangeDelegate * delegate)
 {
     CHIP_FAULT_INJECT(FaultInjection::kFault_AllocExchangeContext, return nullptr);

     for (auto & ec : ContextPool)
     {
         if (ec.GetReferenceCount() == 0)
         {
             return ec.Alloc(this, ExchangeId, PeerNodeId, Initiator, delegate);
         }
     }

     ChipLogError(ExchangeManager, "Alloc ctxt FAILED");
     return nullptr;
 }

 void ExchangeManager::DispatchMessage(const PacketHeader & packetHeader, const PayloadHeader & payloadHeader, PacketBuffer * msgBuf)
 {
     UnsolicitedMessageHandler * umh         = nullptr;
     UnsolicitedMessageHandler * matchingUMH = nullptr;
     CHIP_ERROR err                          = CHIP_NO_ERROR;

     // Search for an existing exchange that the message applies to. If a match is found...
     for (auto & ec : ContextPool)
     {
         if (ec.GetReferenceCount() > 0 && ec.MatchExchange(packetHeader, payloadHeader))
         {
             // Matched ExchangeContext; send to message handler.
             ec.HandleMessage(packetHeader, payloadHeader, msgBuf);

             msgBuf = nullptr;

             ExitNow(err = CHIP_NO_ERROR);
         }
     }

     // Search for an unsolicited message handler if it marked as being sent by an initiator. Since we didn't
     // find an existing exchange that matches the message, it must be an unsolicited message. However all
     // unsolicited messages must be marked as being from an initiator.
     if (payloadHeader.IsInitiator())
     {
         // Search for an unsolicited message handler that can handle the message. Prefer handlers that can explicitly
         // handle the message type over handlers that handle all messages for a profile.
         umh = (UnsolicitedMessageHandler *) UMHandlerPool;

         matchingUMH = nullptr;

         for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
         {
             if (umh->Delegate != nullptr && umh->ProtocolId == payloadHeader.GetProtocolID())
             {
                 if (umh->MessageType == payloadHeader.GetMessageType())
                 {
                     matchingUMH = umh;
                     break;
                 }

                 if (umh->MessageType == kAnyMessageType)
                     matchingUMH = umh;
             }
         }
     }
     // Discard the message if it isn't marked as being sent by an initiator.
     else
     {
         ExitNow(err = CHIP_ERROR_UNSOLICITED_MSG_NO_ORIGINATOR);
     }

     // If we found a handler or we need to create a new exchange context (EC).
     if (matchingUMH != nullptr)
     {
         auto * ec =
             AllocContext(payloadHeader.GetExchangeID(), packetHeader.GetSourceNodeId().Value(), false, matchingUMH->Delegate);
         VerifyOrExit(ec != nullptr, err = CHIP_ERROR_NO_MEMORY);

         ChipLogProgress(ExchangeManager, "ec pos: %d, id: %d, Delegate: 0x%x", ec - ContextPool.begin(), ec->GetExchangeId(),
                         ec->GetDelegate());

         ec->HandleMessage(packetHeader, payloadHeader, msgBuf);
         msgBuf = nullptr;
     }

 exit:
     if (err != CHIP_NO_ERROR)
     {
         ChipLogError(ExchangeManager, "DispatchMessage failed, err = %d", err);
     }

     if (msgBuf != nullptr)
     {
         PacketBuffer::Free(msgBuf);
     }
 }

 CHIP_ERROR ExchangeManager::RegisterUMH(uint32_t protocolId, int16_t msgType, ExchangeDelegate * delegate)
 {
     UnsolicitedMessageHandler * umh      = UMHandlerPool;
     UnsolicitedMessageHandler * selected = nullptr;

     for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
     {
         if (umh->Delegate == nullptr)
         {
             if (selected == nullptr)
                 selected = umh;
         }
         else if (umh->ProtocolId == protocolId && umh->MessageType == msgType)
         {
             umh->Delegate = delegate;
             return CHIP_NO_ERROR;
         }
     }

     if (selected == nullptr)
         return CHIP_ERROR_TOO_MANY_UNSOLICITED_MESSAGE_HANDLERS;

     selected->Delegate    = delegate;
     selected->ProtocolId  = protocolId;
     selected->MessageType = msgType;

     SYSTEM_STATS_INCREMENT(chip::System::Stats::kExchangeMgr_NumUMHandlers);

     return CHIP_NO_ERROR;
 }

 CHIP_ERROR ExchangeManager::UnregisterUMH(uint32_t protocolId, int16_t msgType)
 {
     UnsolicitedMessageHandler * umh = UMHandlerPool;

     for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
     {
         if (umh->Delegate != nullptr && umh->ProtocolId == protocolId && umh->MessageType == msgType)
         {
             umh->Delegate = nullptr;
             SYSTEM_STATS_DECREMENT(chip::System::Stats::kExchangeMgr_NumUMHandlers);
             return CHIP_NO_ERROR;
         }
     }

     return CHIP_ERROR_NO_UNSOLICITED_MESSAGE_HANDLER;
 }

 void ExchangeManager::OnMessageReceived(const PacketHeader & packetHeader, const PayloadHeader & payloadHeader,
                                         const Transport::PeerConnectionState * state, System::PacketBuffer * msgBuf,
                                         SecureSessionMgr * msgLayer)
 {
     DispatchMessage(packetHeader, payloadHeader, msgBuf);
 }

 void ExchangeManager::OnConnectionExpired(const Transport::PeerConnectionState * state, SecureSessionMgr * mgr)
 {
     for (auto & ec : ContextPool)
     {
         if (ec.GetReferenceCount() > 0 && ec.mPeerNodeId == state->GetPeerNodeId())
         {
             ec.Close();
             // Continue iterate because there can be multiple contexts associated with the connection.
         }
     }
 }

 void ExchangeManager::IncrementContextsInUse()
 {
     mContextsInUse++;
 }

 void ExchangeManager::DecrementContextsInUse()
 {
     if (mContextsInUse >= 1)
     {
         mContextsInUse--;
     }
     else
     {
         ChipLogError(ExchangeManager, "No context in use, decrement failed");
     }
 }

 } // namespace chip
	/*
	*
	* Copyright (c) 2020 Project CHIP Authors
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/**
	* @file
	* This file implements the ExchangeManager class.
	*
	*/

	#ifndef __STDC_FORMAT_MACROS
	#define __STDC_FORMAT_MACROS
	#endif

	#ifndef __STDC_LIMIT_MACROS
	#define __STDC_LIMIT_MACROS
	#endif

	#include <cstring>
	#include <inttypes.h>
	#include <stddef.h>

	#include <core/CHIPCore.h>
	#include <core/CHIPEncoding.h>
	#include <messaging/ExchangeContext.h>
	#include <messaging/ExchangeMgr.h>
	#include <support/CHIPFaultInjection.h>
	#include <support/CodeUtils.h>
	#include <support/RandUtils.h>
	#include <support/logging/CHIPLogging.h>

	using namespace chip::Encoding;
	using namespace chip::Inet;
	using namespace chip::System;

	namespace chip {

	/**
	* Constructor for the ExchangeManager class.
	* It sets the state to kState_NotInitialized.
	*
	* @note
	* The class must be initialized via ExchangeManager::Init()
	* prior to use.
	*
	*/
	ExchangeManager::ExchangeManager()
	{
	mState = State::kState_NotInitialized;
	}

	CHIP_ERROR ExchangeManager::Init(SecureSessionMgr * sessionMgr)
	{
	if (mState != State::kState_NotInitialized)
	return CHIP_ERROR_INCORRECT_STATE;

	mSessionMgr = sessionMgr;

	mNextExchangeId = GetRandU16();

	mContextsInUse = 0;

	memset(UMHandlerPool, 0, sizeof(UMHandlerPool));
	OnExchangeContextChanged = nullptr;

	sessionMgr->SetDelegate(this);

	mState = State::kState_Initialized;

	return CHIP_NO_ERROR;
	}

	CHIP_ERROR ExchangeManager::Shutdown()
	{
	if (mSessionMgr != nullptr)
	{
	mSessionMgr->SetDelegate(nullptr);
	mSessionMgr = nullptr;
	}

	OnExchangeContextChanged = nullptr;

	mState = State::kState_NotInitialized;

	return CHIP_NO_ERROR;
	}

	ExchangeContext * ExchangeManager::NewContext(const NodeId & peerNodeId, ExchangeDelegate * delegate)
	{
	return AllocContext(mNextExchangeId++, peerNodeId, true, delegate);
	}

	ExchangeContext * ExchangeManager::FindContext(NodeId peerNodeId, ExchangeDelegate * delegate, bool isInitiator)
	{
	for (auto & ec : ContextPool)
	{
	if (ec.GetReferenceCount() > 0 && ec.GetPeerNodeId() == peerNodeId && ec.GetDelegate() == delegate &&
	ec.IsInitiator() == isInitiator)
	return &ec;
	}

	return nullptr;
	}

	CHIP_ERROR ExchangeManager::RegisterUnsolicitedMessageHandler(uint32_t protocolId, ExchangeDelegate * delegate)
	{
	return RegisterUMH(protocolId, kAnyMessageType, delegate);
	}

	CHIP_ERROR ExchangeManager::RegisterUnsolicitedMessageHandler(uint32_t protocolId, uint8_t msgType, ExchangeDelegate * delegate)
	{
	return RegisterUMH(protocolId, static_cast<int16_t>(msgType), delegate);
	}

	CHIP_ERROR ExchangeManager::UnregisterUnsolicitedMessageHandler(uint32_t protocolId)
	{
	return UnregisterUMH(protocolId, kAnyMessageType);
	}

	CHIP_ERROR ExchangeManager::UnregisterUnsolicitedMessageHandler(uint32_t protocolId, uint8_t msgType)
	{
	return UnregisterUMH(protocolId, static_cast<int16_t>(msgType));
	}

	void ExchangeManager::OnReceiveError(CHIP_ERROR error, const Transport::PeerAddress & source, SecureSessionMgr * msgLayer)
	{
	ChipLogError(ExchangeManager, "Accept FAILED, err = %s", ErrorStr(error));
	}

	ExchangeContext * ExchangeManager::AllocContext(uint16_t ExchangeId, uint64_t PeerNodeId, bool Initiator,
	ExchangeDelegate * delegate)
	{
	CHIP_FAULT_INJECT(FaultInjection::kFault_AllocExchangeContext, return nullptr);

	for (auto & ec : ContextPool)
	{
	if (ec.GetReferenceCount() == 0)
	{
	return ec.Alloc(this, ExchangeId, PeerNodeId, Initiator, delegate);
	}
	}

	ChipLogError(ExchangeManager, "Alloc ctxt FAILED");
	return nullptr;
	}

	void ExchangeManager::DispatchMessage(const PacketHeader & packetHeader, const PayloadHeader & payloadHeader, PacketBuffer * msgBuf)
	{
	UnsolicitedMessageHandler * umh = nullptr;
	UnsolicitedMessageHandler * matchingUMH = nullptr;
	CHIP_ERROR err = CHIP_NO_ERROR;

	// Search for an existing exchange that the message applies to. If a match is found...
	for (auto & ec : ContextPool)
	{
	if (ec.GetReferenceCount() > 0 && ec.MatchExchange(packetHeader, payloadHeader))
	{
	// Matched ExchangeContext; send to message handler.
	ec.HandleMessage(packetHeader, payloadHeader, msgBuf);

	msgBuf = nullptr;

	ExitNow(err = CHIP_NO_ERROR);
	}
	}

	// Search for an unsolicited message handler if it marked as being sent by an initiator. Since we didn't
	// find an existing exchange that matches the message, it must be an unsolicited message. However all
	// unsolicited messages must be marked as being from an initiator.
	if (payloadHeader.IsInitiator())
	{
	// Search for an unsolicited message handler that can handle the message. Prefer handlers that can explicitly
	// handle the message type over handlers that handle all messages for a profile.
	umh = (UnsolicitedMessageHandler *) UMHandlerPool;

	matchingUMH = nullptr;

	for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
	{
	if (umh->Delegate != nullptr && umh->ProtocolId == payloadHeader.GetProtocolID())
	{
	if (umh->MessageType == payloadHeader.GetMessageType())
	{
	matchingUMH = umh;
	break;
	}

	if (umh->MessageType == kAnyMessageType)
	matchingUMH = umh;
	}
	}
	}
	// Discard the message if it isn't marked as being sent by an initiator.
	else
	{
	ExitNow(err = CHIP_ERROR_UNSOLICITED_MSG_NO_ORIGINATOR);
	}

	// If we found a handler or we need to create a new exchange context (EC).
	if (matchingUMH != nullptr)
	{
	auto * ec =
	AllocContext(payloadHeader.GetExchangeID(), packetHeader.GetSourceNodeId().Value(), false, matchingUMH->Delegate);
	VerifyOrExit(ec != nullptr, err = CHIP_ERROR_NO_MEMORY);

	ChipLogProgress(ExchangeManager, "ec pos: %d, id: %d, Delegate: 0x%x", ec - ContextPool.begin(), ec->GetExchangeId(),
	ec->GetDelegate());

	ec->HandleMessage(packetHeader, payloadHeader, msgBuf);
	msgBuf = nullptr;
	}

	exit:
	if (err != CHIP_NO_ERROR)
	{
	ChipLogError(ExchangeManager, "DispatchMessage failed, err = %d", err);
	}

	if (msgBuf != nullptr)
	{
	PacketBuffer::Free(msgBuf);
	}
	}

	CHIP_ERROR ExchangeManager::RegisterUMH(uint32_t protocolId, int16_t msgType, ExchangeDelegate * delegate)
	{
	UnsolicitedMessageHandler * umh = UMHandlerPool;
	UnsolicitedMessageHandler * selected = nullptr;

	for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
	{
	if (umh->Delegate == nullptr)
	{
	if (selected == nullptr)
	selected = umh;
	}
	else if (umh->ProtocolId == protocolId && umh->MessageType == msgType)
	{
	umh->Delegate = delegate;
	return CHIP_NO_ERROR;
	}
	}

	if (selected == nullptr)
	return CHIP_ERROR_TOO_MANY_UNSOLICITED_MESSAGE_HANDLERS;

	selected->Delegate = delegate;
	selected->ProtocolId = protocolId;
	selected->MessageType = msgType;

	SYSTEM_STATS_INCREMENT(chip::System::Stats::kExchangeMgr_NumUMHandlers);

	return CHIP_NO_ERROR;
	}

	CHIP_ERROR ExchangeManager::UnregisterUMH(uint32_t protocolId, int16_t msgType)
	{
	UnsolicitedMessageHandler * umh = UMHandlerPool;

	for (int i = 0; i < CHIP_CONFIG_MAX_UNSOLICITED_MESSAGE_HANDLERS; i++, umh++)
	{
	if (umh->Delegate != nullptr && umh->ProtocolId == protocolId && umh->MessageType == msgType)
	{
	umh->Delegate = nullptr;
	SYSTEM_STATS_DECREMENT(chip::System::Stats::kExchangeMgr_NumUMHandlers);
	return CHIP_NO_ERROR;
	}
	}

	return CHIP_ERROR_NO_UNSOLICITED_MESSAGE_HANDLER;
	}

	void ExchangeManager::OnMessageReceived(const PacketHeader & packetHeader, const PayloadHeader & payloadHeader,
	const Transport::PeerConnectionState * state, System::PacketBuffer * msgBuf,
	SecureSessionMgr * msgLayer)
	{
	DispatchMessage(packetHeader, payloadHeader, msgBuf);
	}

	void ExchangeManager::OnConnectionExpired(const Transport::PeerConnectionState * state, SecureSessionMgr * mgr)
	{
	for (auto & ec : ContextPool)
	{
	if (ec.GetReferenceCount() > 0 && ec.mPeerNodeId == state->GetPeerNodeId())
	{
	ec.Close();
	// Continue iterate because there can be multiple contexts associated with the connection.
	}
	}
	}

	void ExchangeManager::IncrementContextsInUse()
	{
	mContextsInUse++;
	}

	void ExchangeManager::DecrementContextsInUse()
	{
	if (mContextsInUse >= 1)
	{
	mContextsInUse--;
	}
	else
	{
	ChipLogError(ExchangeManager, "No context in use, decrement failed");
	}
	}

	} // namespace chip