| /* |
| * |
| * Copyright (c) 2020-2021 Project CHIP Authors |
| * Copyright (c) 2013-2017 Nest Labs, Inc. |
| * 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 |
| * This file implements the CHIP Connection object that maintains a UDP connection. |
| * TODO This class should be extended to support TCP as well... |
| * |
| */ |
| |
| #include "SecureSessionMgr.h" |
| |
| #include <inttypes.h> |
| #include <string.h> |
| |
| #include <app/util/basic-types.h> |
| #include <core/CHIPKeyIds.h> |
| #include <platform/CHIPDeviceLayer.h> |
| #include <protocols/secure_channel/Constants.h> |
| #include <support/CodeUtils.h> |
| #include <support/SafeInt.h> |
| #include <support/logging/CHIPLogging.h> |
| #include <transport/FabricTable.h> |
| #include <transport/SecureMessageCodec.h> |
| #include <transport/TransportMgr.h> |
| |
| #include <inttypes.h> |
| |
| namespace chip { |
| |
| using System::PacketBufferHandle; |
| using Transport::PeerAddress; |
| using Transport::PeerConnectionState; |
| |
| uint32_t EncryptedPacketBufferHandle::GetMsgId() const |
| { |
| PacketHeader header; |
| uint16_t headerSize = 0; |
| CHIP_ERROR err = header.Decode((*this)->Start(), (*this)->DataLength(), &headerSize); |
| |
| if (err == CHIP_NO_ERROR) |
| { |
| return header.GetMessageId(); |
| } |
| |
| ChipLogError(Inet, "Failed to decode EncryptedPacketBufferHandle header with error: %s", ErrorStr(err)); |
| |
| return 0; |
| } |
| |
| SecureSessionMgr::SecureSessionMgr() : mState(State::kNotReady) {} |
| |
| SecureSessionMgr::~SecureSessionMgr() |
| { |
| CancelExpiryTimer(); |
| } |
| |
| CHIP_ERROR SecureSessionMgr::Init(System::Layer * systemLayer, TransportMgrBase * transportMgr, Transport::FabricTable * fabrics, |
| Transport::MessageCounterManagerInterface * messageCounterManager) |
| { |
| VerifyOrReturnError(mState == State::kNotReady, CHIP_ERROR_INCORRECT_STATE); |
| VerifyOrReturnError(transportMgr != nullptr, CHIP_ERROR_INVALID_ARGUMENT); |
| |
| mState = State::kInitialized; |
| mSystemLayer = systemLayer; |
| mTransportMgr = transportMgr; |
| mFabrics = fabrics; |
| mMessageCounterManager = messageCounterManager; |
| |
| mGlobalEncryptedMessageCounter.Init(); |
| |
| ScheduleExpiryTimer(); |
| |
| mTransportMgr->SetSecureSessionMgr(this); |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| void SecureSessionMgr::Shutdown() |
| { |
| CancelExpiryTimer(); |
| |
| mMessageCounterManager = nullptr; |
| |
| mState = State::kNotReady; |
| mSystemLayer = nullptr; |
| mTransportMgr = nullptr; |
| mFabrics = nullptr; |
| mCB = nullptr; |
| } |
| |
| CHIP_ERROR SecureSessionMgr::BuildEncryptedMessagePayload(SecureSessionHandle session, PayloadHeader & payloadHeader, |
| System::PacketBufferHandle && msgBuf, |
| EncryptedPacketBufferHandle & encryptedMessage) |
| { |
| PacketHeader packetHeader; |
| if (IsControlMessage(payloadHeader)) |
| { |
| packetHeader.SetSecureSessionControlMsg(true); |
| } |
| |
| PeerConnectionState * state = GetPeerConnectionState(session); |
| if (state == nullptr) |
| { |
| return CHIP_ERROR_NOT_CONNECTED; |
| } |
| |
| MessageCounter & counter = GetSendCounterForPacket(payloadHeader, *state); |
| ReturnErrorOnFailure(SecureMessageCodec::Encode(state, payloadHeader, packetHeader, msgBuf, counter)); |
| |
| ReturnErrorOnFailure(packetHeader.EncodeBeforeData(msgBuf)); |
| |
| encryptedMessage = EncryptedPacketBufferHandle::MarkEncrypted(std::move(msgBuf)); |
| ChipLogProgress(Inet, "Encrypted message %p to 0x" ChipLogFormatX64 " of type %d and protocolId %" PRIu32 " on exchange %d.", |
| &encryptedMessage, ChipLogValueX64(state->GetPeerNodeId()), payloadHeader.GetMessageType(), |
| payloadHeader.GetProtocolID().ToFullyQualifiedSpecForm(), payloadHeader.GetExchangeID()); |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| CHIP_ERROR SecureSessionMgr::SendPreparedMessage(SecureSessionHandle session, const EncryptedPacketBufferHandle & preparedMessage) |
| { |
| CHIP_ERROR err = CHIP_NO_ERROR; |
| PeerConnectionState * state = nullptr; |
| PacketBufferHandle msgBuf; |
| |
| VerifyOrExit(mState == State::kInitialized, err = CHIP_ERROR_INCORRECT_STATE); |
| VerifyOrExit(!preparedMessage.IsNull(), err = CHIP_ERROR_INVALID_ARGUMENT); |
| msgBuf = preparedMessage.CastToWritable(); |
| VerifyOrExit(!msgBuf.IsNull(), err = CHIP_ERROR_INVALID_ARGUMENT); |
| VerifyOrExit(!msgBuf->HasChainedBuffer(), err = CHIP_ERROR_INVALID_MESSAGE_LENGTH); |
| |
| // Find an active connection to the specified peer node |
| state = GetPeerConnectionState(session); |
| VerifyOrExit(state != nullptr, err = CHIP_ERROR_NOT_CONNECTED); |
| |
| // This marks any connection where we send data to as 'active' |
| mPeerConnections.MarkConnectionActive(state); |
| |
| ChipLogProgress(Inet, "Sending msg %p to 0x" ChipLogFormatX64 " at utc time: %" PRId64 " msec", &preparedMessage, |
| ChipLogValueX64(state->GetPeerNodeId()), System::Clock::GetMonotonicMilliseconds()); |
| |
| if (mTransportMgr != nullptr) |
| { |
| ChipLogProgress(Inet, "Sending secure msg on generic transport"); |
| err = mTransportMgr->SendMessage(state->GetPeerAddress(), std::move(msgBuf)); |
| } |
| else |
| { |
| ChipLogError(Inet, "The transport manager is not initialized. Unable to send the message"); |
| err = CHIP_ERROR_INCORRECT_STATE; |
| } |
| ChipLogProgress(Inet, "Secure msg send status %s", ErrorStr(err)); |
| SuccessOrExit(err); |
| |
| exit: |
| if (!msgBuf.IsNull()) |
| { |
| const char * errStr = ErrorStr(err); |
| if (state == nullptr) |
| { |
| ChipLogError(Inet, "Secure transport could not find a valid PeerConnection: %s", errStr); |
| } |
| } |
| |
| return err; |
| } |
| |
| void SecureSessionMgr::ExpirePairing(SecureSessionHandle session) |
| { |
| PeerConnectionState * state = GetPeerConnectionState(session); |
| if (state != nullptr) |
| { |
| mPeerConnections.MarkConnectionExpired( |
| state, [this](const Transport::PeerConnectionState & state1) { HandleConnectionExpired(state1); }); |
| } |
| } |
| |
| void SecureSessionMgr::ExpireAllPairings(NodeId peerNodeId, FabricIndex fabric) |
| { |
| PeerConnectionState * state = mPeerConnections.FindPeerConnectionState(peerNodeId, nullptr); |
| while (state != nullptr) |
| { |
| if (fabric == state->GetFabricIndex()) |
| { |
| mPeerConnections.MarkConnectionExpired( |
| state, [this](const Transport::PeerConnectionState & state1) { HandleConnectionExpired(state1); }); |
| state = mPeerConnections.FindPeerConnectionState(peerNodeId, nullptr); |
| } |
| else |
| { |
| state = mPeerConnections.FindPeerConnectionState(peerNodeId, state); |
| } |
| } |
| } |
| |
| CHIP_ERROR SecureSessionMgr::NewPairing(const Optional<Transport::PeerAddress> & peerAddr, NodeId peerNodeId, |
| PairingSession * pairing, SecureSession::SessionRole direction, FabricIndex fabric) |
| { |
| uint16_t peerKeyId = pairing->GetPeerKeyId(); |
| uint16_t localKeyId = pairing->GetLocalKeyId(); |
| PeerConnectionState * state = mPeerConnections.FindPeerConnectionState(Optional<NodeId>::Value(peerNodeId), peerKeyId, nullptr); |
| |
| // Find any existing connection with the same node and key ID |
| if (state && (state->GetFabricIndex() == Transport::kUndefinedFabricIndex || state->GetFabricIndex() == fabric)) |
| { |
| mPeerConnections.MarkConnectionExpired( |
| state, [this](const Transport::PeerConnectionState & state1) { HandleConnectionExpired(state1); }); |
| } |
| |
| ChipLogDetail(Inet, "New secure session created for device 0x" ChipLogFormatX64 ", key %d!!", ChipLogValueX64(peerNodeId), |
| peerKeyId); |
| state = nullptr; |
| ReturnErrorOnFailure( |
| mPeerConnections.CreateNewPeerConnectionState(Optional<NodeId>::Value(peerNodeId), peerKeyId, localKeyId, &state)); |
| ReturnErrorCodeIf(state == nullptr, CHIP_ERROR_NO_MEMORY); |
| |
| state->SetFabricIndex(fabric); |
| |
| if (peerAddr.HasValue() && peerAddr.Value().GetIPAddress() != Inet::IPAddress::Any) |
| { |
| state->SetPeerAddress(peerAddr.Value()); |
| } |
| else if (peerAddr.HasValue() && peerAddr.Value().GetTransportType() == Transport::Type::kBle) |
| { |
| state->SetPeerAddress(peerAddr.Value()); |
| } |
| else if (peerAddr.HasValue() && |
| (peerAddr.Value().GetTransportType() == Transport::Type::kTcp || |
| peerAddr.Value().GetTransportType() == Transport::Type::kUdp)) |
| { |
| return CHIP_ERROR_INVALID_ARGUMENT; |
| } |
| |
| ReturnErrorOnFailure(pairing->DeriveSecureSession(state->GetSecureSession(), direction)); |
| |
| if (mCB != nullptr) |
| { |
| state->GetSessionMessageCounter().GetPeerMessageCounter().SetCounter(pairing->GetPeerCounter()); |
| mCB->OnNewConnection({ state->GetPeerNodeId(), state->GetPeerKeyID(), fabric }); |
| } |
| |
| return CHIP_NO_ERROR; |
| } |
| |
| void SecureSessionMgr::ScheduleExpiryTimer() |
| { |
| CHIP_ERROR err = |
| mSystemLayer->StartTimer(CHIP_PEER_CONNECTION_TIMEOUT_CHECK_FREQUENCY_MS, SecureSessionMgr::ExpiryTimerCallback, this); |
| |
| VerifyOrDie(err == CHIP_NO_ERROR); |
| } |
| |
| void SecureSessionMgr::CancelExpiryTimer() |
| { |
| if (mSystemLayer != nullptr) |
| { |
| mSystemLayer->CancelTimer(SecureSessionMgr::ExpiryTimerCallback, this); |
| } |
| } |
| |
| void SecureSessionMgr::OnMessageReceived(const PeerAddress & peerAddress, System::PacketBufferHandle && msg) |
| { |
| PacketHeader packetHeader; |
| |
| ReturnOnFailure(packetHeader.DecodeAndConsume(msg)); |
| |
| if (packetHeader.GetFlags().Has(Header::FlagValues::kEncryptedMessage)) |
| { |
| SecureMessageDispatch(packetHeader, peerAddress, std::move(msg)); |
| } |
| else |
| { |
| MessageDispatch(packetHeader, peerAddress, std::move(msg)); |
| } |
| } |
| |
| void SecureSessionMgr::MessageDispatch(const PacketHeader & packetHeader, const Transport::PeerAddress & peerAddress, |
| System::PacketBufferHandle && msg) |
| { |
| if (mCB != nullptr) |
| { |
| PayloadHeader payloadHeader; |
| ReturnOnFailure(payloadHeader.DecodeAndConsume(msg)); |
| mCB->OnMessageReceived(packetHeader, payloadHeader, SecureSessionHandle(), peerAddress, |
| SecureSessionMgrDelegate::DuplicateMessage::No, std::move(msg)); |
| } |
| } |
| |
| void SecureSessionMgr::SecureMessageDispatch(const PacketHeader & packetHeader, const Transport::PeerAddress & peerAddress, |
| System::PacketBufferHandle && msg) |
| { |
| CHIP_ERROR err = CHIP_NO_ERROR; |
| |
| PeerConnectionState * state = mPeerConnections.FindPeerConnectionState(packetHeader.GetEncryptionKeyID(), nullptr); |
| |
| PayloadHeader payloadHeader; |
| |
| SecureSessionMgrDelegate::DuplicateMessage isDuplicate = SecureSessionMgrDelegate::DuplicateMessage::No; |
| |
| VerifyOrExit(!msg.IsNull(), ChipLogError(Inet, "Secure transport received NULL packet, discarding")); |
| |
| if (state == nullptr) |
| { |
| ChipLogError(Inet, "Data received on an unknown connection (%d). Dropping it!!", packetHeader.GetEncryptionKeyID()); |
| ExitNow(err = CHIP_ERROR_KEY_NOT_FOUND_FROM_PEER); |
| } |
| |
| // Verify message counter |
| if (packetHeader.GetFlags().Has(Header::FlagValues::kSecureSessionControlMessage)) |
| { |
| // TODO: control message counter is not implemented yet |
| } |
| else |
| { |
| if (!state->GetSessionMessageCounter().GetPeerMessageCounter().IsSynchronized()) |
| { |
| // Queue and start message sync procedure |
| err = mMessageCounterManager->QueueReceivedMessageAndStartSync( |
| packetHeader, { state->GetPeerNodeId(), state->GetPeerKeyID(), state->GetFabricIndex() }, state, peerAddress, |
| std::move(msg)); |
| |
| if (err != CHIP_NO_ERROR) |
| { |
| ChipLogError(Inet, |
| "Message counter synchronization for received message, failed to " |
| "QueueReceivedMessageAndStartSync, err = %" CHIP_ERROR_FORMAT, |
| err.Format()); |
| } |
| else |
| { |
| ChipLogDetail(Inet, "Received message have been queued due to peer counter is not synced"); |
| } |
| |
| return; |
| } |
| |
| err = state->GetSessionMessageCounter().GetPeerMessageCounter().Verify(packetHeader.GetMessageId()); |
| if (err == CHIP_ERROR_DUPLICATE_MESSAGE_RECEIVED) |
| { |
| ChipLogDetail(Inet, "Received a duplicate message"); |
| isDuplicate = SecureSessionMgrDelegate::DuplicateMessage::Yes; |
| err = CHIP_NO_ERROR; |
| } |
| if (err != CHIP_NO_ERROR) |
| { |
| ChipLogError(Inet, "Message counter verify failed, err = %" CHIP_ERROR_FORMAT, err.Format()); |
| } |
| SuccessOrExit(err); |
| } |
| |
| mPeerConnections.MarkConnectionActive(state); |
| |
| // Decode the message |
| VerifyOrExit(CHIP_NO_ERROR == SecureMessageCodec::Decode(state, payloadHeader, packetHeader, msg), |
| ChipLogError(Inet, "Secure transport received message, but failed to decode it, discarding")); |
| |
| if (isDuplicate == SecureSessionMgrDelegate::DuplicateMessage::Yes && !payloadHeader.NeedsAck()) |
| { |
| // If it's a duplicate message, but doesn't require an ack, let's drop it right here to save CPU |
| // cycles on further message processing. |
| ExitNow(err = CHIP_NO_ERROR); |
| } |
| |
| if (packetHeader.GetFlags().Has(Header::FlagValues::kSecureSessionControlMessage)) |
| { |
| // TODO: control message counter is not implemented yet |
| } |
| else |
| { |
| state->GetSessionMessageCounter().GetPeerMessageCounter().Commit(packetHeader.GetMessageId()); |
| } |
| |
| // TODO: once mDNS address resolution is available reconsider if this is required |
| // This updates the peer address once a packet is received from a new address |
| // and serves as a way to auto-detect peer changing IPs. |
| if (state->GetPeerAddress() != peerAddress) |
| { |
| state->SetPeerAddress(peerAddress); |
| } |
| |
| if (mCB != nullptr) |
| { |
| SecureSessionHandle session(state->GetPeerNodeId(), state->GetPeerKeyID(), state->GetFabricIndex()); |
| mCB->OnMessageReceived(packetHeader, payloadHeader, session, peerAddress, isDuplicate, std::move(msg)); |
| } |
| |
| exit: |
| if (err != CHIP_NO_ERROR && mCB != nullptr) |
| { |
| mCB->OnReceiveError(err, peerAddress); |
| } |
| } |
| |
| void SecureSessionMgr::HandleConnectionExpired(const Transport::PeerConnectionState & state) |
| { |
| ChipLogDetail(Inet, "Marking old secure session for device 0x" ChipLogFormatX64 " as expired", |
| ChipLogValueX64(state.GetPeerNodeId())); |
| |
| if (mCB != nullptr) |
| { |
| mCB->OnConnectionExpired({ state.GetPeerNodeId(), state.GetPeerKeyID(), state.GetFabricIndex() }); |
| } |
| |
| mTransportMgr->Disconnect(state.GetPeerAddress()); |
| } |
| |
| void SecureSessionMgr::ExpiryTimerCallback(System::Layer * layer, void * param) |
| { |
| SecureSessionMgr * mgr = reinterpret_cast<SecureSessionMgr *>(param); |
| #if CHIP_CONFIG_SESSION_REKEYING |
| // TODO(#2279): session expiration is currently disabled until rekeying is supported |
| // the #ifdef should be removed after that. |
| mgr->mPeerConnections.ExpireInactiveConnections( |
| CHIP_PEER_CONNECTION_TIMEOUT_MS, |
| [this](const Transport::PeerConnectionState & state1) { HandleConnectionExpired(state1); }); |
| #endif |
| mgr->ScheduleExpiryTimer(); // re-schedule the oneshot timer |
| } |
| |
| PeerConnectionState * SecureSessionMgr::GetPeerConnectionState(SecureSessionHandle session) |
| { |
| return mPeerConnections.FindPeerConnectionState(Optional<NodeId>::Value(session.mPeerNodeId), session.mPeerKeyId, nullptr); |
| } |
| |
| } // namespace chip |