src/transport/TransportMgr.cpp

/*
 *
 *    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
 */

/**
 * @file
 *   This file implements a stateless TransportMgr, it will took a raw message
 * buffer from transports, and then extract the message header without decode it.
 * For secure messages, it will pass it to the SecureSessionMgr, and for unsecure
 * messages (rendezvous messages), it will pass it to RendezvousSession.
 *   When sending messages, it will encode the packet header, and pass it to the
 * transports.
 *   The whole process is fully stateless.
 */

#include <transport/TransportMgr.h>

#include <transport/RendezvousSession.h>
#include <transport/SecureSessionMgr.h>
#include <transport/raw/Base.h>
#include <transport/raw/MessageHeader.h>
#include <transport/raw/PeerAddress.h>

namespace chip {

CHIP_ERROR TransportMgrBase::Init(Transport::Base * transport)
{
    if (mTransport != nullptr)
    {
        return CHIP_ERROR_INCORRECT_STATE;
    }
    mTransport = transport;
    mTransport->SetMessageReceiveHandler(HandleMessageReceived, this);
    ChipLogDetail(Inet, "TransportMgr initialized");
    return CHIP_NO_ERROR;
}

void TransportMgrBase::HandleMessageReceived(const PacketHeader & packetHeader, const Transport::PeerAddress & peerAddress,
                                             System::PacketBufferHandle msg, TransportMgrBase * dispatcher)
{
    TransportMgrDelegate * handler =
        packetHeader.GetFlags().Has(Header::FlagValues::kSecure) ? dispatcher->mSecureSessionMgr : dispatcher->mRendezvous;
    if (handler != nullptr)
    {
        handler->OnMessageReceived(packetHeader, peerAddress, std::move(msg));
    }
    else
    {
        char addrBuffer[Transport::PeerAddress::kMaxToStringSize];
        peerAddress.ToString(addrBuffer, sizeof(addrBuffer));
        ChipLogError(Inet, "%s message from %s is dropped since no corresponding handler is set in TransportMgr.",
                     packetHeader.GetFlags().Has(Header::FlagValues::kSecure) ? "Encrypted" : "Unencrypted", addrBuffer);
    }
}
} // namespace chip