/// <summary>
/// Sends a request message to the client over the open network stream and stores the request to the list of unfinished requests.
/// </summary>
/// <param name="Message">Message to send.</param>
/// <param name="Context">Caller's defined context to store information required for later response processing.</param>
/// <returns>true if the connection to the client should remain open, false otherwise.</returns>
public async Task <bool> SendMessageAndSaveUnfinishedRequestAsync(Message Message, object Context)
{
log.Trace("()");
bool res = false;
UnfinishedRequest unfinishedRequest = new UnfinishedRequest(Message, Context);
if (AddUnfinishedRequest(unfinishedRequest))
{
res = await SendMessageInternalAsync(Message);
if (res)
{
// If the message was sent successfully to the target, we close the connection only in case it was a protocol violation error response.
if (Message.MessageTypeCase == Message.MessageTypeOneofCase.Response)
{
res = Message.Response.Status != Status.ErrorProtocolViolation;
}
}
else
{
RemoveUnfinishedRequest(unfinishedRequest.RequestMessage.Id);
}
}
log.Trace("(-):{0}", res);
return(res);
}
/// <summary>
/// Adds unfinished request to the list of unfinished requests.
/// </summary>
/// <param name="Request">Request to add to the list.</param>
/// <returns>true if the function succeeds, false if the number of unfinished requests is over the limit.</returns>
public bool AddUnfinishedRequest(UnfinishedRequest Request)
{
log.Trace("(Request.RequestMessage.Id:{0})", Request.RequestMessage.Id);
bool res = false;
lock (unfinishedRequestsLock)
{
unfinishedRequests.Add(Request.RequestMessage.Id, Request);
res = true;
}
log.Trace("(-):{0},unfinishedRequests.Count={1}", res, unfinishedRequests.Count);
return(res);
}
/// <summary>
/// Finds an unfinished request message by its ID and removes it from the list.
/// </summary>
/// <param name="Id">Identifier of the message to find.</param>
/// <returns>Unfinished request with the given ID, or null if no such request is in the list.</returns>
public UnfinishedRequest GetAndRemoveUnfinishedRequest(uint Id)
{
log.Trace("(Id:{0})", Id);
UnfinishedRequest res = null;
lock (unfinishedRequestsLock)
{
if (unfinishedRequests.TryGetValue(Id, out res))
{
unfinishedRequests.Remove(Id);
}
}
log.Trace("(-):{0},unfinishedRequests.Count={1}", res != null ? "UnfinishedRequest" : "null", unfinishedRequests.Count);
return(res);
}
/// <summary>
/// Processes FinishNeighborhoodInitializationResponse message from client.
/// </summary>
/// <param name="Client">Client that sent the response.</param>
/// <param name="ResponseMessage">Full response message.</param>
/// <param name="Request">Unfinished request message that corresponds to the response message.</param>
/// <returns>true if the connection to the client that sent the response should remain open, false if the client should be disconnected.</returns>
public bool ProcessMessageFinishNeighborhoodInitializationResponse(IncomingClient Client, Message ResponseMessage, UnfinishedRequest Request)
{
log.Trace("()");
bool res = true;
log.Trace("(-):{0}", res);
return(res);
}
/// <summary>
/// Processes NeighborhoodSharedProfileUpdateResponse message from client.
/// </summary>
/// <param name="Client">Client that sent the response.</param>
/// <param name="ResponseMessage">Full response message.</param>
/// <param name="Request">Unfinished request message that corresponds to the response message.</param>
/// <returns>true if the connection to the client that sent the response should remain open, false if the client should be disconnected.</returns>
public bool ProcessMessageNeighborhoodSharedProfileUpdateResponse(IncomingClient Client, Message ResponseMessage, UnfinishedRequest Request)
{
log.Trace("()");
bool res = true;
log.Trace("(-):{0}", res);
return(res);
}
/// <summary>
/// Processing of a message received from a client.
/// </summary>
/// <param name="Client">TCP client who send the message.</param>
/// <param name="IncomingMessage">Full ProtoBuf message to be processed.</param>
/// <returns>true if the conversation with the client should continue, false if a protocol violation error occurred and the client should be disconnected.</returns>
public async Task <bool> ProcessMessageAsync(IncomingClient Client, Message IncomingMessage)
{
MessageBuilder messageBuilder = Client.MessageBuilder;
bool res = false;
log.Debug("()");
try
{
log.Trace("Received message type is {0}, message ID is {1}.", IncomingMessage.MessageTypeCase, IncomingMessage.Id);
switch (IncomingMessage.MessageTypeCase)
{
case Message.MessageTypeOneofCase.Request:
{
Message responseMessage = messageBuilder.CreateErrorProtocolViolationResponse(IncomingMessage);
Request request = IncomingMessage.Request;
log.Trace("Request conversation type is {0}.", request.ConversationTypeCase);
switch (request.ConversationTypeCase)
{
case Request.ConversationTypeOneofCase.SingleRequest:
{
SingleRequest singleRequest = request.SingleRequest;
SemVer version = new SemVer(singleRequest.Version);
log.Trace("Single request type is {0}, version is {1}.", singleRequest.RequestTypeCase, version);
if (!version.IsValid())
{
responseMessage.Response.Details = "version";
break;
}
switch (singleRequest.RequestTypeCase)
{
case SingleRequest.RequestTypeOneofCase.Ping:
responseMessage = ProcessMessagePingRequest(Client, IncomingMessage);
break;
case SingleRequest.RequestTypeOneofCase.ListRoles:
responseMessage = ProcessMessageListRolesRequest(Client, IncomingMessage);
break;
default:
log.Warn("Invalid request type '{0}'.", singleRequest.RequestTypeCase);
break;
}
break;
}
case Request.ConversationTypeOneofCase.ConversationRequest:
{
ConversationRequest conversationRequest = request.ConversationRequest;
log.Trace("Conversation request type is {0}.", conversationRequest.RequestTypeCase);
if (conversationRequest.Signature.Length > 0)
{
log.Trace("Conversation signature is '{0}'.", Crypto.ToHex(conversationRequest.Signature.ToByteArray()));
}
else
{
log.Trace("No signature provided.");
}
switch (conversationRequest.RequestTypeCase)
{
case ConversationRequest.RequestTypeOneofCase.Start:
responseMessage = ProcessMessageStartConversationRequest(Client, IncomingMessage);
break;
case ConversationRequest.RequestTypeOneofCase.VerifyIdentity:
responseMessage = ProcessMessageVerifyIdentityRequest(Client, IncomingMessage);
break;
case ConversationRequest.RequestTypeOneofCase.StartNeighborhoodInitialization:
responseMessage = ProcessMessageStartNeighborhoodInitializationRequest(Client, IncomingMessage);
break;
case ConversationRequest.RequestTypeOneofCase.FinishNeighborhoodInitialization:
responseMessage = ProcessMessageFinishNeighborhoodInitializationRequest(Client, IncomingMessage);
break;
case ConversationRequest.RequestTypeOneofCase.NeighborhoodSharedProfileUpdate:
responseMessage = ProcessMessageNeighborhoodSharedProfileUpdateRequest(Client, IncomingMessage);
break;
case ConversationRequest.RequestTypeOneofCase.StopNeighborhoodUpdates:
responseMessage = ProcessMessageStopNeighborhoodUpdatesRequest(Client, IncomingMessage);
break;
default:
log.Warn("Invalid request type '{0}'.", conversationRequest.RequestTypeCase);
// Connection will be closed in ReceiveMessageLoop.
break;
}
break;
}
default:
log.Error("Unknown conversation type '{0}'.", request.ConversationTypeCase);
// Connection will be closed in ReceiveMessageLoop.
break;
}
if (responseMessage != null)
{
// Send response to client.
res = await Client.SendMessageAsync(responseMessage);
}
else
{
// If there is no response to send immediately to the client,
// we want to keep the connection open.
res = true;
}
break;
}
case Message.MessageTypeOneofCase.Response:
{
Response response = IncomingMessage.Response;
log.Trace("Response status is {0}, details are '{1}', conversation type is {2}.", response.Status, response.Details, response.ConversationTypeCase);
// Find associated request. If it does not exist, disconnect the client as it
// send a response without receiving a request. This is protocol violation,
// but as this is a reponse, we have no how to inform the client about it,
// so we just disconnect it.
UnfinishedRequest unfinishedRequest = Client.GetAndRemoveUnfinishedRequest(IncomingMessage.Id);
if ((unfinishedRequest != null) && (unfinishedRequest.RequestMessage != null))
{
Message requestMessage = unfinishedRequest.RequestMessage;
Request request = requestMessage.Request;
// We now check whether the response message type corresponds with the request type.
// This is only valid if the status is Ok. If the message types do not match, we disconnect
// for the protocol violation again.
bool typeMatch = false;
bool isErrorResponse = response.Status != Status.Ok;
if (!isErrorResponse)
{
if (response.ConversationTypeCase == Response.ConversationTypeOneofCase.SingleResponse)
{
typeMatch = (request.ConversationTypeCase == Request.ConversationTypeOneofCase.SingleRequest) &&
((int)response.SingleResponse.ResponseTypeCase == (int)request.SingleRequest.RequestTypeCase);
}
else
{
typeMatch = (request.ConversationTypeCase == Request.ConversationTypeOneofCase.ConversationRequest) &&
((int)response.ConversationResponse.ResponseTypeCase == (int)request.ConversationRequest.RequestTypeCase);
}
}
else
{
typeMatch = true;
}
if (typeMatch)
{
// Now we know the types match, so we can rely on request type even if response is just an error.
switch (request.ConversationTypeCase)
{
case Request.ConversationTypeOneofCase.SingleRequest:
{
SingleRequest singleRequest = request.SingleRequest;
switch (singleRequest.RequestTypeCase)
{
default:
log.Warn("Invalid conversation type '{0}' of the corresponding request.", request.ConversationTypeCase);
// Connection will be closed in ReceiveMessageLoop.
break;
}
break;
}
case Request.ConversationTypeOneofCase.ConversationRequest:
{
ConversationRequest conversationRequest = request.ConversationRequest;
switch (conversationRequest.RequestTypeCase)
{
case ConversationRequest.RequestTypeOneofCase.NeighborhoodSharedProfileUpdate:
res = ProcessMessageNeighborhoodSharedProfileUpdateResponse(Client, IncomingMessage, unfinishedRequest);
break;
case ConversationRequest.RequestTypeOneofCase.FinishNeighborhoodInitialization:
res = ProcessMessageFinishNeighborhoodInitializationResponse(Client, IncomingMessage, unfinishedRequest);
break;
default:
log.Warn("Invalid type '{0}' of the corresponding request.", conversationRequest.RequestTypeCase);
// Connection will be closed in ReceiveMessageLoop.
break;
}
break;
}
default:
log.Error("Unknown conversation type '{0}' of the corresponding request.", request.ConversationTypeCase);
// Connection will be closed in ReceiveMessageLoop.
break;
}
}
else
{
log.Warn("Message type of the response ID {0} does not match the message type of the request ID {1}, the connection will be closed.", IncomingMessage.Id);
// Connection will be closed in ReceiveMessageLoop.
}
}
else
{
log.Warn("No unfinished request found for incoming response ID {0}, the connection will be closed.", IncomingMessage.Id);
// Connection will be closed in ReceiveMessageLoop.
}
break;
}
default:
log.Error("Unknown message type '{0}', connection to the client will be closed.", IncomingMessage.MessageTypeCase);
await SendProtocolViolation(Client);
// Connection will be closed in ReceiveMessageLoop.
break;
}
}
catch (Exception e)
{
log.Error("Exception occurred, connection to the client will be closed: {0}", e.ToString());
await SendProtocolViolation(Client);
// Connection will be closed in ReceiveMessageLoop.
}
if (res && Client.ForceDisconnect)
{
log.Debug("Connection to the client will be forcefully closed.");
res = false;
}
profileServer.AddMessage(IncomingMessage, Client.ServerRole, res ? Client : null);
log.Debug("(-):{0}", res);
return(res);
}
