blob: 7cec122a9bcdebfc866f47873f8db44bfef473da [file] [log] [blame]
/*
*
* 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 "SessionManager.h"
#include <inttypes.h>
#include <string.h>
#include "transport/TraceMessage.h"
#include <app/util/basic-types.h>
#include <credentials/GroupDataProvider.h>
#include <inttypes.h>
#include <lib/core/CHIPKeyIds.h>
#include <lib/support/CodeUtils.h>
#include <lib/support/SafeInt.h>
#include <lib/support/logging/CHIPLogging.h>
#include <platform/CHIPDeviceLayer.h>
#include <protocols/Protocols.h>
#include <protocols/secure_channel/Constants.h>
#include <transport/GroupPeerMessageCounter.h>
#include <transport/GroupSession.h>
#include <transport/SecureMessageCodec.h>
#include <transport/TransportMgr.h>
// Global object
chip::Transport::GroupPeerTable mGroupPeerMsgCounter;
namespace chip {
using System::PacketBufferHandle;
using Transport::PeerAddress;
using Transport::SecureSession;
uint32_t EncryptedPacketBufferHandle::GetMessageCounter() const
{
PacketHeader header;
uint16_t headerSize = 0;
CHIP_ERROR err = header.Decode((*this)->Start(), (*this)->DataLength(), &headerSize);
if (err == CHIP_NO_ERROR)
{
return header.GetMessageCounter();
}
ChipLogError(Inet, "Failed to decode EncryptedPacketBufferHandle header with error: %" CHIP_ERROR_FORMAT, err.Format());
return 0;
}
SessionManager::SessionManager() : mState(State::kNotReady) {}
SessionManager::~SessionManager()
{
this->Shutdown();
}
CHIP_ERROR SessionManager::Init(System::Layer * systemLayer, TransportMgrBase * transportMgr,
Transport::MessageCounterManagerInterface * messageCounterManager,
chip::PersistentStorageDelegate * storageDelegate, FabricTable * fabricTable)
{
VerifyOrReturnError(mState == State::kNotReady, CHIP_ERROR_INCORRECT_STATE);
VerifyOrReturnError(transportMgr != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
VerifyOrReturnError(storageDelegate != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
VerifyOrReturnError(fabricTable != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
ReturnErrorOnFailure(fabricTable->AddFabricDelegate(this));
mState = State::kInitialized;
mSystemLayer = systemLayer;
mTransportMgr = transportMgr;
mMessageCounterManager = messageCounterManager;
mFabricTable = fabricTable;
mSecureSessions.Init();
mGlobalUnencryptedMessageCounter.Init();
ReturnErrorOnFailure(mGroupClientCounter.Init(storageDelegate));
mTransportMgr->SetSessionManager(this);
return CHIP_NO_ERROR;
}
void SessionManager::Shutdown()
{
if (mFabricTable != nullptr)
{
mFabricTable->RemoveFabricDelegate(this);
mFabricTable = nullptr;
}
// Ensure that we don't create new sessions as we iterate our session table.
mState = State::kNotReady;
mSecureSessions.ForEachSession([&](auto session) {
session->MarkForEviction();
return Loop::Continue;
});
mMessageCounterManager = nullptr;
mSystemLayer = nullptr;
mTransportMgr = nullptr;
mCB = nullptr;
}
/**
* @brief Notification that a fabric was removed.
* This function doesn't call ExpireAllSessionsForFabric
* since the CASE session might still be open to send a response
* on the removed fabric.
*/
void SessionManager::FabricRemoved(FabricIndex fabricIndex)
{
mGroupPeerMsgCounter.FabricRemoved(fabricIndex);
}
CHIP_ERROR SessionManager::PrepareMessage(const SessionHandle & sessionHandle, PayloadHeader & payloadHeader,
System::PacketBufferHandle && message, EncryptedPacketBufferHandle & preparedMessage)
{
PacketHeader packetHeader;
bool isControlMsg = IsControlMessage(payloadHeader);
if (isControlMsg)
{
packetHeader.SetSecureSessionControlMsg(true);
}
#if CHIP_PROGRESS_LOGGING
NodeId destination;
FabricIndex fabricIndex;
#endif // CHIP_PROGRESS_LOGGING
switch (sessionHandle->GetSessionType())
{
case Transport::Session::SessionType::kGroupOutgoing: {
auto groupSession = sessionHandle->AsOutgoingGroupSession();
auto * groups = Credentials::GetGroupDataProvider();
VerifyOrReturnError(nullptr != groups, CHIP_ERROR_INTERNAL);
const FabricInfo * fabric = mFabricTable->FindFabricWithIndex(groupSession->GetFabricIndex());
VerifyOrReturnError(fabric != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
packetHeader.SetDestinationGroupId(groupSession->GetGroupId());
packetHeader.SetMessageCounter(mGroupClientCounter.GetCounter(isControlMsg));
mGroupClientCounter.IncrementCounter(isControlMsg);
packetHeader.SetSessionType(Header::SessionType::kGroupSession);
NodeId sourceNodeId = fabric->GetNodeId();
packetHeader.SetSourceNodeId(sourceNodeId);
if (!packetHeader.IsValidGroupMsg())
{
return CHIP_ERROR_INTERNAL;
}
// Trace before any encryption
CHIP_TRACE_MESSAGE_SENT(payloadHeader, packetHeader, message->Start(), message->TotalLength());
Crypto::SymmetricKeyContext * keyContext =
groups->GetKeyContext(groupSession->GetFabricIndex(), groupSession->GetGroupId());
VerifyOrReturnError(nullptr != keyContext, CHIP_ERROR_INTERNAL);
packetHeader.SetSessionId(keyContext->GetKeyHash());
CryptoContext::NonceStorage nonce;
CryptoContext::BuildNonce(nonce, packetHeader.GetSecurityFlags(), packetHeader.GetMessageCounter(), sourceNodeId);
CHIP_ERROR err = SecureMessageCodec::Encrypt(CryptoContext(keyContext), nonce, payloadHeader, packetHeader, message);
keyContext->Release();
ReturnErrorOnFailure(err);
#if CHIP_PROGRESS_LOGGING
destination = NodeIdFromGroupId(groupSession->GetGroupId());
fabricIndex = groupSession->GetFabricIndex();
#endif // CHIP_PROGRESS_LOGGING
}
break;
case Transport::Session::SessionType::kSecure: {
SecureSession * session = sessionHandle->AsSecureSession();
if (session == nullptr)
{
return CHIP_ERROR_NOT_CONNECTED;
}
MessageCounter & counter = session->GetSessionMessageCounter().GetLocalMessageCounter();
uint32_t messageCounter;
ReturnErrorOnFailure(counter.AdvanceAndConsume(messageCounter));
packetHeader
.SetMessageCounter(messageCounter) //
.SetSessionId(session->GetPeerSessionId()) //
.SetSessionType(Header::SessionType::kUnicastSession);
// Trace before any encryption
CHIP_TRACE_MESSAGE_SENT(payloadHeader, packetHeader, message->Start(), message->TotalLength());
CryptoContext::NonceStorage nonce;
NodeId sourceNodeId = session->GetLocalScopedNodeId().GetNodeId();
CryptoContext::BuildNonce(nonce, packetHeader.GetSecurityFlags(), messageCounter, sourceNodeId);
ReturnErrorOnFailure(SecureMessageCodec::Encrypt(session->GetCryptoContext(), nonce, payloadHeader, packetHeader, message));
#if CHIP_PROGRESS_LOGGING
destination = session->GetPeerNodeId();
fabricIndex = session->GetFabricIndex();
#endif // CHIP_PROGRESS_LOGGING
}
break;
case Transport::Session::SessionType::kUnauthenticated: {
MessageCounter & counter = mGlobalUnencryptedMessageCounter;
uint32_t messageCounter;
ReturnErrorOnFailure(counter.AdvanceAndConsume(messageCounter));
packetHeader.SetMessageCounter(messageCounter);
Transport::UnauthenticatedSession * session = sessionHandle->AsUnauthenticatedSession();
switch (session->GetSessionRole())
{
case Transport::UnauthenticatedSession::SessionRole::kInitiator:
packetHeader.SetSourceNodeId(session->GetEphemeralInitiatorNodeID());
break;
case Transport::UnauthenticatedSession::SessionRole::kResponder:
packetHeader.SetDestinationNodeId(session->GetEphemeralInitiatorNodeID());
break;
}
// Trace after all headers are settled.
CHIP_TRACE_MESSAGE_SENT(payloadHeader, packetHeader, message->Start(), message->TotalLength());
ReturnErrorOnFailure(payloadHeader.EncodeBeforeData(message));
#if CHIP_PROGRESS_LOGGING
destination = kUndefinedNodeId;
fabricIndex = kUndefinedFabricIndex;
#endif // CHIP_PROGRESS_LOGGING
}
break;
default:
return CHIP_ERROR_INTERNAL;
}
#if CHIP_PROGRESS_LOGGING
CompressedFabricId compressedFabricId = kUndefinedCompressedFabricId;
if (fabricIndex != kUndefinedFabricIndex && mFabricTable != nullptr)
{
auto fabricInfo = mFabricTable->FindFabricWithIndex(fabricIndex);
if (fabricInfo)
{
compressedFabricId = fabricInfo->GetCompressedFabricId();
}
}
auto * protocolName = Protocols::GetProtocolName(payloadHeader.GetProtocolID());
auto * msgTypeName = Protocols::GetMessageTypeName(payloadHeader.GetProtocolID(), payloadHeader.GetMessageType());
//
// 32-bit value maximum = 10 chars + text preamble (6) + trailer (1) + null (1) + 2 buffer = 20
//
char ackBuf[20];
ackBuf[0] = '\0';
if (payloadHeader.GetAckMessageCounter().HasValue())
{
snprintf(ackBuf, sizeof(ackBuf), " (Ack:" ChipLogFormatMessageCounter ")", payloadHeader.GetAckMessageCounter().Value());
}
//
// Legend that can be used to decode this log line can be found in messaging/README.md
//
ChipLogProgress(ExchangeManager,
"<<< [E:" ChipLogFormatExchangeId " M:" ChipLogFormatMessageCounter "%s] (%s) Msg TX to %u:" ChipLogFormatX64
" [%04X] --- Type %04X:%02X (%s:%s)",
ChipLogValueExchangeIdFromSentHeader(payloadHeader), packetHeader.GetMessageCounter(), ackBuf,
Transport::GetSessionTypeString(sessionHandle), fabricIndex, ChipLogValueX64(destination),
static_cast<uint16_t>(compressedFabricId), payloadHeader.GetProtocolID().GetProtocolId(),
payloadHeader.GetMessageType(), protocolName, msgTypeName);
#endif
ReturnErrorOnFailure(packetHeader.EncodeBeforeData(message));
preparedMessage = EncryptedPacketBufferHandle::MarkEncrypted(std::move(message));
return CHIP_NO_ERROR;
}
CHIP_ERROR SessionManager::SendPreparedMessage(const SessionHandle & sessionHandle,
const EncryptedPacketBufferHandle & preparedMessage)
{
VerifyOrReturnError(mState == State::kInitialized, CHIP_ERROR_INCORRECT_STATE);
VerifyOrReturnError(!preparedMessage.IsNull(), CHIP_ERROR_INVALID_ARGUMENT);
Transport::PeerAddress multicastAddress; // Only used for the group case
const Transport::PeerAddress * destination;
switch (sessionHandle->GetSessionType())
{
case Transport::Session::SessionType::kGroupOutgoing: {
auto groupSession = sessionHandle->AsOutgoingGroupSession();
const FabricInfo * fabric = mFabricTable->FindFabricWithIndex(groupSession->GetFabricIndex());
VerifyOrReturnError(fabric != nullptr, CHIP_ERROR_INVALID_ARGUMENT);
multicastAddress = Transport::PeerAddress::Multicast(fabric->GetFabricId(), groupSession->GetGroupId());
destination = &multicastAddress;
char addressStr[Transport::PeerAddress::kMaxToStringSize];
multicastAddress.ToString(addressStr, Transport::PeerAddress::kMaxToStringSize);
ChipLogProgress(Inet, "(G) Sending msg " ChipLogFormatMessageCounter " to Multicast IPV6 address '%s'",
preparedMessage.GetMessageCounter(), addressStr);
}
break;
case Transport::Session::SessionType::kSecure: {
// Find an active connection to the specified peer node
SecureSession * secure = sessionHandle->AsSecureSession();
// This marks any connection where we send data to as 'active'
secure->MarkActive();
destination = &secure->GetPeerAddress();
ChipLogProgress(Inet, "(S) Sending msg " ChipLogFormatMessageCounter " on secure session with LSID: %u",
preparedMessage.GetMessageCounter(), secure->GetLocalSessionId());
}
break;
case Transport::Session::SessionType::kUnauthenticated: {
auto unauthenticated = sessionHandle->AsUnauthenticatedSession();
unauthenticated->MarkActive();
destination = &unauthenticated->GetPeerAddress();
#if CHIP_PROGRESS_LOGGING
char addressStr[Transport::PeerAddress::kMaxToStringSize];
destination->ToString(addressStr);
ChipLogProgress(Inet, "(U) Sending msg " ChipLogFormatMessageCounter " to IP address '%s'",
preparedMessage.GetMessageCounter(), addressStr);
#endif
}
break;
default:
return CHIP_ERROR_INTERNAL;
}
PacketBufferHandle msgBuf = preparedMessage.CastToWritable();
VerifyOrReturnError(!msgBuf.IsNull(), CHIP_ERROR_INVALID_ARGUMENT);
VerifyOrReturnError(!msgBuf->HasChainedBuffer(), CHIP_ERROR_INVALID_MESSAGE_LENGTH);
#if CHIP_SYSTEM_CONFIG_MULTICAST_HOMING
if (sessionHandle->GetSessionType() == Transport::Session::SessionType::kGroupOutgoing)
{
chip::Inet::InterfaceIterator interfaceIt;
chip::Inet::InterfaceId interfaceId = chip::Inet::InterfaceId::Null();
chip::Inet::IPAddress addr;
bool interfaceFound = false;
while (interfaceIt.Next())
{
char name[chip::Inet::InterfaceId::kMaxIfNameLength];
interfaceIt.GetInterfaceName(name, chip::Inet::InterfaceId::kMaxIfNameLength);
if (interfaceIt.SupportsMulticast() && interfaceIt.IsUp())
{
interfaceId = interfaceIt.GetInterfaceId();
if (CHIP_NO_ERROR == interfaceId.GetLinkLocalAddr(&addr))
{
ChipLogDetail(Inet, "Interface %s has a link local address", name);
interfaceFound = true;
PacketBufferHandle tempBuf = msgBuf.CloneData();
VerifyOrReturnError(!tempBuf.IsNull(), CHIP_ERROR_INVALID_ARGUMENT);
VerifyOrReturnError(!tempBuf->HasChainedBuffer(), CHIP_ERROR_INVALID_MESSAGE_LENGTH);
destination = &(multicastAddress.SetInterface(interfaceId));
if (mTransportMgr != nullptr)
{
CHIP_TRACE_PREPARED_MESSAGE_SENT(destination, &tempBuf);
if (CHIP_NO_ERROR != mTransportMgr->SendMessage(*destination, std::move(tempBuf)))
{
ChipLogError(Inet, "Failed to send Multicast message on interface %s", name);
}
else
{
ChipLogDetail(Inet, "Successfully send Multicast message on interface %s", name);
}
}
}
}
}
if (!interfaceFound)
{
ChipLogError(Inet, "No valid Interface found.. Sending to the default one.. ");
}
else
{
// Always return No error, because we expect some interface to fails and others to always succeed (e.g. lo interface)
return CHIP_NO_ERROR;
}
}
#endif // CHIP_SYSTEM_CONFIG_MULTICAST_HOMING
if (mTransportMgr != nullptr)
{
CHIP_TRACE_PREPARED_MESSAGE_SENT(destination, &msgBuf);
return mTransportMgr->SendMessage(*destination, std::move(msgBuf));
}
ChipLogError(Inet, "The transport manager is not initialized. Unable to send the message");
return CHIP_ERROR_INCORRECT_STATE;
}
void SessionManager::ExpireAllSessions(const ScopedNodeId & node)
{
ChipLogDetail(Inet, "Expiring all sessions for node " ChipLogFormatScopedNodeId "!!", ChipLogValueScopedNodeId(node));
ForEachMatchingSession(node, [](auto * session) { session->MarkForEviction(); });
}
void SessionManager::ExpireAllSessionsForFabric(FabricIndex fabricIndex)
{
ChipLogDetail(Inet, "Expiring all sessions for fabric 0x%x!!", static_cast<unsigned>(fabricIndex));
ForEachMatchingSession(fabricIndex, [](auto * session) { session->MarkForEviction(); });
}
CHIP_ERROR SessionManager::ExpireAllSessionsOnLogicalFabric(const ScopedNodeId & node)
{
ChipLogDetail(Inet, "Expiring all sessions to peer " ChipLogFormatScopedNodeId " that are on the same logical fabric!!",
ChipLogValueScopedNodeId(node));
return ForEachMatchingSessionOnLogicalFabric(node, [](auto * session) { session->MarkForEviction(); });
}
CHIP_ERROR SessionManager::ExpireAllSessionsOnLogicalFabric(FabricIndex fabricIndex)
{
ChipLogDetail(Inet, "Expiring all sessions on the same logical fabric as fabric 0x%x!!", static_cast<unsigned>(fabricIndex));
return ForEachMatchingSessionOnLogicalFabric(fabricIndex, [](auto * session) { session->MarkForEviction(); });
}
void SessionManager::ExpireAllPASESessions()
{
ChipLogDetail(Inet, "Expiring all PASE sessions");
mSecureSessions.ForEachSession([&](auto session) {
if (session->GetSecureSessionType() == Transport::SecureSession::Type::kPASE)
{
session->MarkForEviction();
}
return Loop::Continue;
});
}
void SessionManager::MarkSessionsAsDefunct(const ScopedNodeId & node, const Optional<Transport::SecureSession::Type> & type)
{
mSecureSessions.ForEachSession([&node, &type](auto session) {
if (session->IsActiveSession() && session->GetPeer() == node &&
(!type.HasValue() || type.Value() == session->GetSecureSessionType()))
{
session->MarkAsDefunct();
}
return Loop::Continue;
});
}
void SessionManager::UpdateAllSessionsPeerAddress(const ScopedNodeId & node, const Transport::PeerAddress & addr)
{
mSecureSessions.ForEachSession([&node, &addr](auto session) {
// Arguably we should only be updating active and defunct sessions, but there is no harm
// in updating evicted sessions.
if (session->GetPeer() == node && Transport::SecureSession::Type::kCASE == session->GetSecureSessionType())
{
session->SetPeerAddress(addr);
}
return Loop::Continue;
});
}
Optional<SessionHandle> SessionManager::AllocateSession(SecureSession::Type secureSessionType,
const ScopedNodeId & sessionEvictionHint)
{
VerifyOrReturnValue(mState == State::kInitialized, NullOptional);
return mSecureSessions.CreateNewSecureSession(secureSessionType, sessionEvictionHint);
}
CHIP_ERROR SessionManager::InjectPaseSessionWithTestKey(SessionHolder & sessionHolder, uint16_t localSessionId, NodeId peerNodeId,
uint16_t peerSessionId, FabricIndex fabric,
const Transport::PeerAddress & peerAddress, CryptoContext::SessionRole role)
{
NodeId localNodeId = kUndefinedNodeId;
Optional<SessionHandle> session = mSecureSessions.CreateNewSecureSessionForTest(
chip::Transport::SecureSession::Type::kPASE, localSessionId, localNodeId, peerNodeId, CATValues{}, peerSessionId, fabric,
GetLocalMRPConfig().ValueOr(GetDefaultMRPConfig()));
VerifyOrReturnError(session.HasValue(), CHIP_ERROR_NO_MEMORY);
SecureSession * secureSession = session.Value()->AsSecureSession();
secureSession->SetPeerAddress(peerAddress);
size_t secretLen = CHIP_CONFIG_TEST_SHARED_SECRET_LENGTH;
ByteSpan secret(reinterpret_cast<const uint8_t *>(CHIP_CONFIG_TEST_SHARED_SECRET_VALUE), secretLen);
ReturnErrorOnFailure(secureSession->GetCryptoContext().InitFromSecret(
secret, ByteSpan(nullptr, 0), CryptoContext::SessionInfoType::kSessionEstablishment, role));
secureSession->GetSessionMessageCounter().GetPeerMessageCounter().SetCounter(Transport::PeerMessageCounter::kInitialSyncValue);
sessionHolder.Grab(session.Value());
return CHIP_NO_ERROR;
}
CHIP_ERROR SessionManager::InjectCaseSessionWithTestKey(SessionHolder & sessionHolder, uint16_t localSessionId,
uint16_t peerSessionId, NodeId localNodeId, NodeId peerNodeId,
FabricIndex fabric, const Transport::PeerAddress & peerAddress,
CryptoContext::SessionRole role, const CATValues & cats)
{
Optional<SessionHandle> session = mSecureSessions.CreateNewSecureSessionForTest(
chip::Transport::SecureSession::Type::kCASE, localSessionId, localNodeId, peerNodeId, cats, peerSessionId, fabric,
GetLocalMRPConfig().ValueOr(GetDefaultMRPConfig()));
VerifyOrReturnError(session.HasValue(), CHIP_ERROR_NO_MEMORY);
SecureSession * secureSession = session.Value()->AsSecureSession();
secureSession->SetPeerAddress(peerAddress);
size_t secretLen = CHIP_CONFIG_TEST_SHARED_SECRET_LENGTH;
ByteSpan secret(reinterpret_cast<const uint8_t *>(CHIP_CONFIG_TEST_SHARED_SECRET_VALUE), secretLen);
ReturnErrorOnFailure(secureSession->GetCryptoContext().InitFromSecret(
secret, ByteSpan(nullptr, 0), CryptoContext::SessionInfoType::kSessionEstablishment, role));
secureSession->GetSessionMessageCounter().GetPeerMessageCounter().SetCounter(Transport::PeerMessageCounter::kInitialSyncValue);
sessionHolder.Grab(session.Value());
return CHIP_NO_ERROR;
}
void SessionManager::OnMessageReceived(const PeerAddress & peerAddress, System::PacketBufferHandle && msg)
{
CHIP_TRACE_PREPARED_MESSAGE_RECEIVED(&peerAddress, &msg);
PacketHeader partialPacketHeader;
CHIP_ERROR err = partialPacketHeader.DecodeFixed(msg);
if (err != CHIP_NO_ERROR)
{
ChipLogError(Inet, "Failed to decode packet header: %" CHIP_ERROR_FORMAT, err.Format());
return;
}
if (partialPacketHeader.IsEncrypted())
{
if (partialPacketHeader.IsGroupSession())
{
SecureGroupMessageDispatch(partialPacketHeader, peerAddress, std::move(msg));
}
else
{
SecureUnicastMessageDispatch(partialPacketHeader, peerAddress, std::move(msg));
}
}
else
{
UnauthenticatedMessageDispatch(partialPacketHeader, peerAddress, std::move(msg));
}
}
void SessionManager::UnauthenticatedMessageDispatch(const PacketHeader & partialPacketHeader,
const Transport::PeerAddress & peerAddress, System::PacketBufferHandle && msg)
{
// Drop unsecured messages with privacy enabled.
if (partialPacketHeader.HasPrivacyFlag())
{
ChipLogError(Inet, "Dropping unauthenticated message with privacy flag set");
return;
}
PacketHeader packetHeader;
ReturnOnFailure(packetHeader.DecodeAndConsume(msg));
Optional<NodeId> source = packetHeader.GetSourceNodeId();
Optional<NodeId> destination = packetHeader.GetDestinationNodeId();
if ((source.HasValue() && destination.HasValue()) || (!source.HasValue() && !destination.HasValue()))
{
ChipLogProgress(Inet,
"Received malformed unsecure packet with source 0x" ChipLogFormatX64 " destination 0x" ChipLogFormatX64,
ChipLogValueX64(source.ValueOr(kUndefinedNodeId)), ChipLogValueX64(destination.ValueOr(kUndefinedNodeId)));
return; // ephemeral node id is only assigned to the initiator, there should be one and only one node id exists.
}
Optional<SessionHandle> optionalSession;
if (source.HasValue())
{
// Assume peer is the initiator, we are the responder.
optionalSession = mUnauthenticatedSessions.FindOrAllocateResponder(source.Value(), GetDefaultMRPConfig());
if (!optionalSession.HasValue())
{
ChipLogError(Inet, "UnauthenticatedSession exhausted");
return;
}
}
else
{
// Assume peer is the responder, we are the initiator.
optionalSession = mUnauthenticatedSessions.FindInitiator(destination.Value());
if (!optionalSession.HasValue())
{
ChipLogProgress(Inet, "Received unknown unsecure packet for initiator 0x" ChipLogFormatX64,
ChipLogValueX64(destination.Value()));
return;
}
}
const SessionHandle & session = optionalSession.Value();
Transport::UnauthenticatedSession * unsecuredSession = session->AsUnauthenticatedSession();
unsecuredSession->SetPeerAddress(peerAddress);
SessionMessageDelegate::DuplicateMessage isDuplicate = SessionMessageDelegate::DuplicateMessage::No;
unsecuredSession->MarkActiveRx();
PayloadHeader payloadHeader;
ReturnOnFailure(payloadHeader.DecodeAndConsume(msg));
// Verify message counter
CHIP_ERROR err = unsecuredSession->GetPeerMessageCounter().VerifyUnencrypted(packetHeader.GetMessageCounter());
if (err == CHIP_ERROR_DUPLICATE_MESSAGE_RECEIVED)
{
ChipLogDetail(Inet,
"Received a duplicate message with MessageCounter:" ChipLogFormatMessageCounter
" on exchange " ChipLogFormatExchangeId,
packetHeader.GetMessageCounter(), ChipLogValueExchangeIdFromReceivedHeader(payloadHeader));
isDuplicate = SessionMessageDelegate::DuplicateMessage::Yes;
err = CHIP_NO_ERROR;
}
else
{
// VerifyUnencrypted always returns one of CHIP_NO_ERROR or
// CHIP_ERROR_DUPLICATE_MESSAGE_RECEIVED.
unsecuredSession->GetPeerMessageCounter().CommitUnencrypted(packetHeader.GetMessageCounter());
}
if (mCB != nullptr)
{
CHIP_TRACE_MESSAGE_RECEIVED(payloadHeader, packetHeader, unsecuredSession, peerAddress, msg->Start(), msg->TotalLength());
mCB->OnMessageReceived(packetHeader, payloadHeader, session, isDuplicate, std::move(msg));
}
}
void SessionManager::SecureUnicastMessageDispatch(const PacketHeader & partialPacketHeader,
const Transport::PeerAddress & peerAddress, System::PacketBufferHandle && msg)
{
CHIP_ERROR err = CHIP_NO_ERROR;
Optional<SessionHandle> session = mSecureSessions.FindSecureSessionByLocalKey(partialPacketHeader.GetSessionId());
PayloadHeader payloadHeader;
// Drop secure unicast messages with privacy enabled.
if (partialPacketHeader.HasPrivacyFlag())
{
ChipLogError(Inet, "Dropping secure unicast message with privacy flag set");
return;
}
PacketHeader packetHeader;
ReturnOnFailure(packetHeader.DecodeAndConsume(msg));
SessionMessageDelegate::DuplicateMessage isDuplicate = SessionMessageDelegate::DuplicateMessage::No;
if (msg.IsNull())
{
ChipLogError(Inet, "Secure transport received Unicast NULL packet, discarding");
return;
}
if (!session.HasValue())
{
ChipLogError(Inet, "Data received on an unknown session (LSID=%d). Dropping it!", packetHeader.GetSessionId());
return;
}
Transport::SecureSession * secureSession = session.Value()->AsSecureSession();
// We need to allow through messages even on sessions that are pending
// evictions, because for some cases (UpdateNOC, RemoveFabric, etc) there
// can be a single exchange alive on the session waiting for a MRP ack, and
// we need to make sure to send the ack through. The exchange manager is
// responsible for ensuring that such messages do not lead to new exchange
// creation.
if (!secureSession->IsDefunct() && !secureSession->IsActiveSession() && !secureSession->IsPendingEviction())
{
ChipLogError(Inet, "Secure transport received message on a session in an invalid state (state = '%s')",
secureSession->GetStateStr());
return;
}
// Decrypt and verify the message before message counter verification or any further processing.
CryptoContext::NonceStorage nonce;
// PASE Sessions use the undefined node ID of all zeroes, since there is no node ID to use
// and the key is short-lived and always different for each PASE session.
CryptoContext::BuildNonce(nonce, packetHeader.GetSecurityFlags(), packetHeader.GetMessageCounter(),
secureSession->GetSecureSessionType() == SecureSession::Type::kCASE ? secureSession->GetPeerNodeId()
: kUndefinedNodeId);
if (SecureMessageCodec::Decrypt(secureSession->GetCryptoContext(), nonce, payloadHeader, packetHeader, msg) != CHIP_NO_ERROR)
{
ChipLogError(Inet, "Secure transport received message, but failed to decode/authenticate it, discarding");
return;
}
err =
secureSession->GetSessionMessageCounter().GetPeerMessageCounter().VerifyEncryptedUnicast(packetHeader.GetMessageCounter());
if (err == CHIP_ERROR_DUPLICATE_MESSAGE_RECEIVED)
{
ChipLogDetail(Inet,
"Received a duplicate message with MessageCounter:" ChipLogFormatMessageCounter
" on exchange " ChipLogFormatExchangeId,
packetHeader.GetMessageCounter(), ChipLogValueExchangeIdFromReceivedHeader(payloadHeader));
isDuplicate = SessionMessageDelegate::DuplicateMessage::Yes;
err = CHIP_NO_ERROR;
}
if (err != CHIP_NO_ERROR)
{
ChipLogError(Inet, "Message counter verify failed, err = %" CHIP_ERROR_FORMAT, err.Format());
return;
}
secureSession->MarkActiveRx();
if (isDuplicate == SessionMessageDelegate::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.
return;
}
if (isDuplicate == SessionMessageDelegate::DuplicateMessage::No)
{
secureSession->GetSessionMessageCounter().GetPeerMessageCounter().CommitEncryptedUnicast(packetHeader.GetMessageCounter());
}
// 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 (secureSession->GetPeerAddress() != peerAddress)
{
secureSession->SetPeerAddress(peerAddress);
}
if (mCB != nullptr)
{
CHIP_TRACE_MESSAGE_RECEIVED(payloadHeader, packetHeader, secureSession, peerAddress, msg->Start(), msg->TotalLength());
mCB->OnMessageReceived(packetHeader, payloadHeader, session.Value(), isDuplicate, std::move(msg));
}
}
/**
* Helper function to implement a single attempt to decrypt a groupcast message
* using the given group key and privacy setting.
*
* @param[in] partialPacketHeader The partial packet header with non-obfuscated message fields (result of calling DecodeFixed).
* @param[out] packetHeaderCopy A copy of the packet header, to be filled with privacy decrypted fields
* @param[out] payloadHeader The payload header of the decrypted message
* @param[in] applyPrivacy Whether to apply privacy deobfuscation
* @param[out] msgCopy A copy of the message, to be filled with the decrypted message
* @param[in] mac The MAC of the message
* @param[in] groupContext The group context to use for decryption key material
*
* @return true if the message was decrypted successfully
* @return false if the message could not be decrypted
*/
static bool GroupKeyDecryptAttempt(const PacketHeader & partialPacketHeader, PacketHeader & packetHeaderCopy,
PayloadHeader & payloadHeader, bool applyPrivacy, System::PacketBufferHandle & msgCopy,
const MessageAuthenticationCode & mac,
const Credentials::GroupDataProvider::GroupSession & groupContext)
{
bool decrypted = false;
CryptoContext context(groupContext.keyContext);
if (applyPrivacy)
{
// Perform privacy deobfuscation, if applicable.
uint8_t * privacyHeader = partialPacketHeader.PrivacyHeader(msgCopy->Start());
size_t privacyLength = partialPacketHeader.PrivacyHeaderLength();
if (CHIP_NO_ERROR != context.PrivacyDecrypt(privacyHeader, privacyLength, privacyHeader, partialPacketHeader, mac))
{
return false;
}
}
if (packetHeaderCopy.DecodeAndConsume(msgCopy) != CHIP_NO_ERROR)
{
ChipLogError(Inet, "Failed to decode Groupcast packet header. Discarding.");
return false;
}
// Optimization to reduce number of decryption attempts
GroupId groupId = packetHeaderCopy.GetDestinationGroupId().Value();
if (groupId != groupContext.group_id)
{
return false;
}
CryptoContext::NonceStorage nonce;
CryptoContext::BuildNonce(nonce, packetHeaderCopy.GetSecurityFlags(), packetHeaderCopy.GetMessageCounter(),
packetHeaderCopy.GetSourceNodeId().Value());
decrypted = (CHIP_NO_ERROR == SecureMessageCodec::Decrypt(context, nonce, payloadHeader, packetHeaderCopy, msgCopy));
return decrypted;
}
void SessionManager::SecureGroupMessageDispatch(const PacketHeader & partialPacketHeader,
const Transport::PeerAddress & peerAddress, System::PacketBufferHandle && msg)
{
PayloadHeader payloadHeader;
PacketHeader packetHeaderCopy; /// Packet header decoded per group key, with privacy decrypted fields
System::PacketBufferHandle msgCopy;
Credentials::GroupDataProvider * groups = Credentials::GetGroupDataProvider();
VerifyOrReturn(nullptr != groups);
CHIP_ERROR err = CHIP_NO_ERROR;
if (!partialPacketHeader.HasDestinationGroupId())
{
return; // malformed packet
}
// Check if Message Header is valid first
if (!(partialPacketHeader.IsValidMCSPMsg() || partialPacketHeader.IsValidGroupMsg()))
{
ChipLogError(Inet, "Invalid condition found in packet header");
return;
}
// Trial decryption with GroupDataProvider
Credentials::GroupDataProvider::GroupSession groupContext;
auto iter = groups->IterateGroupSessions(partialPacketHeader.GetSessionId());
if (iter == nullptr)
{
ChipLogError(Inet, "Failed to retrieve Groups iterator. Discarding everything");
return;
}
// Extract MIC from the end of the message.
uint8_t * data = msg->Start();
uint16_t len = msg->DataLength();
uint16_t footerLen = partialPacketHeader.MICTagLength();
VerifyOrReturn(footerLen <= len);
uint16_t taglen = 0;
MessageAuthenticationCode mac;
ReturnOnFailure(mac.Decode(partialPacketHeader, &data[len - footerLen], footerLen, &taglen));
VerifyOrReturn(taglen == footerLen);
bool decrypted = false;
while (!decrypted && iter->Next(groupContext))
{
CryptoContext context(groupContext.keyContext);
msgCopy = msg.CloneData();
if (msgCopy.IsNull())
{
ChipLogError(Inet, "Failed to clone Groupcast message buffer. Discarding.");
return;
}
bool privacy = partialPacketHeader.HasPrivacyFlag();
decrypted =
GroupKeyDecryptAttempt(partialPacketHeader, packetHeaderCopy, payloadHeader, privacy, msgCopy, mac, groupContext);
#if CHIP_CONFIG_PRIVACY_ACCEPT_NONSPEC_SVE2
if (privacy && !decrypted)
{
// Try processing the P=1 message again without privacy as a work-around for invalid early-SVE2 nodes.
msgCopy = msg.CloneData();
if (msgCopy.IsNull())
{
ChipLogError(Inet, "Failed to clone Groupcast message buffer. Discarding.");
return;
}
decrypted =
GroupKeyDecryptAttempt(partialPacketHeader, packetHeaderCopy, payloadHeader, false, msgCopy, mac, groupContext);
}
#endif // CHIP_CONFIG_PRIVACY_ACCEPT_NONSPEC_SVE2
}
iter->Release();
if (!decrypted)
{
ChipLogError(Inet, "Failed to decrypt group message. Discarding everything");
return;
}
msg = std::move(msgCopy);
// MCSP check
if (packetHeaderCopy.IsValidMCSPMsg())
{
// TODO: When MCSP Msg, create Secure Session instead of a Group session
// TODO
// if (packetHeaderCopy.GetDestinationNodeId().Value() == ThisDeviceNodeID)
// {
// MCSP processing..
// }
return;
}
// Group Messages should never send an Ack
if (payloadHeader.NeedsAck())
{
ChipLogError(Inet, "Unexpected ACK requested for group message");
return;
}
// Handle Group message counter here spec 4.7.3
// spec 4.5.1.2 for msg counter
Transport::PeerMessageCounter * counter = nullptr;
if (CHIP_NO_ERROR ==
mGroupPeerMsgCounter.FindOrAddPeer(groupContext.fabric_index, packetHeaderCopy.GetSourceNodeId().Value(),
packetHeaderCopy.IsSecureSessionControlMsg(), counter))
{
if (Credentials::GroupDataProvider::SecurityPolicy::kTrustFirst == groupContext.security_policy)
{
err = counter->VerifyOrTrustFirstGroup(packetHeaderCopy.GetMessageCounter());
}
else
{
// TODO support cache and sync with MCSP. Issue #11689
ChipLogError(Inet, "Received Group Msg with key policy Cache and Sync, but MCSP is not implemented");
return;
// cache and sync
// err = counter->VerifyGroup(packetHeaderCopy.GetMessageCounter());
}
if (err != CHIP_NO_ERROR)
{
// Exit now, since Group Messages don't have acks or responses of any kind.
ChipLogError(Inet, "Message counter verify failed, err = %" CHIP_ERROR_FORMAT, err.Format());
return;
}
}
else
{
ChipLogError(Inet,
"Group Counter Tables full or invalid NodeId/FabricIndex after decryption of message, dropping everything");
return;
}
counter->CommitGroup(packetHeaderCopy.GetMessageCounter());
if (mCB != nullptr)
{
// TODO : When MCSP is done, clean up session creation logic
Transport::IncomingGroupSession groupSession(groupContext.group_id, groupContext.fabric_index,
packetHeaderCopy.GetSourceNodeId().Value());
CHIP_TRACE_MESSAGE_RECEIVED(payloadHeader, packetHeaderCopy, &groupSession, peerAddress, msg->Start(), msg->TotalLength());
mCB->OnMessageReceived(packetHeaderCopy, payloadHeader, SessionHandle(groupSession),
SessionMessageDelegate::DuplicateMessage::No, std::move(msg));
}
}
Optional<SessionHandle> SessionManager::FindSecureSessionForNode(ScopedNodeId peerNodeId,
const Optional<Transport::SecureSession::Type> & type)
{
SecureSession * found = nullptr;
mSecureSessions.ForEachSession([&peerNodeId, &type, &found](auto session) {
if (session->IsActiveSession() && session->GetPeer() == peerNodeId &&
(!type.HasValue() || type.Value() == session->GetSecureSessionType()))
{
//
// Select the active session with the most recent activity to return back to the caller.
//
if ((found == nullptr) || (found->GetLastActivityTime() < session->GetLastActivityTime()))
{
found = session;
}
}
return Loop::Continue;
});
return found != nullptr ? MakeOptional<SessionHandle>(*found) : Optional<SessionHandle>::Missing();
}
/**
* Provides a means to get diagnostic information such as number of sessions.
*/
[[maybe_unused]] CHIP_ERROR SessionManager::ForEachSessionHandle(void * context, SessionHandleCallback lambda)
{
mSecureSessions.ForEachSession([&](auto session) {
SessionHandle handle(*session);
lambda(context, handle);
return Loop::Continue;
});
return CHIP_NO_ERROR;
}
} // namespace chip