internal static ISCSIPDU GetSCSIDataOutResponsePDU(SCSIDataOutPDU request, ISCSITarget target, SessionParameters session, ConnectionParameters connection) { string connectionIdentifier = StateObject.GetConnectionIdentifier(session, connection); TransferEntry transfer = connection.GetTransferEntry(request.TargetTransferTag); if (transfer == null) { ISCSIServer.Log("[{0}][GetSCSIDataOutResponsePDU] Invalid TargetTransferTag {1}", connectionIdentifier, request.TargetTransferTag); RejectPDU reject = new RejectPDU(); reject.InitiatorTaskTag = request.InitiatorTaskTag; reject.Reason = RejectReason.InvalidPDUField; reject.Data = ByteReader.ReadBytes(request.GetBytes(), 0, 48); return(reject); } ushort LUN = (ushort)request.LUN; Disk disk = target.Disks[LUN]; uint offset = request.BufferOffset; uint totalLength = (uint)transfer.CommandDataBuffer.Length; // Store segment (we only execute the command after receiving all of its data) Array.Copy(request.Data, 0, transfer.CommandDataBuffer, offset, request.DataSegmentLength); ISCSIServer.Log(String.Format("[{0}][GetSCSIDataOutResponsePDU] Buffer offset: {1}, Total length: {2}", connectionIdentifier, offset, totalLength)); if (offset + request.DataSegmentLength == totalLength) { // Last Data-out PDU ISCSIServer.Log("[{0}][GetSCSIDataOutResponsePDU] Last Data-out PDU", connectionIdentifier); byte[] scsiResponse; SCSIStatusCodeName status = target.ExecuteCommand(transfer.CommandBytes, request.LUN, transfer.CommandDataBuffer, out scsiResponse); SCSIResponsePDU response = new SCSIResponsePDU(); response.InitiatorTaskTag = request.InitiatorTaskTag; response.Status = status; response.Data = scsiResponse; connection.RemoveTransfer(request.TargetTransferTag); return(response); } else { // Send R2T ReadyToTransferPDU response = new ReadyToTransferPDU(); response.InitiatorTaskTag = request.InitiatorTaskTag; response.TargetTransferTag = request.TargetTransferTag; response.R2TSN = transfer.NextR2NSN; response.BufferOffset = offset + request.DataSegmentLength; // where we left off response.DesiredDataTransferLength = Math.Min((uint)connection.TargetMaxRecvDataSegmentLength, totalLength - response.BufferOffset); transfer.NextR2NSN++; return(response); } }
internal static List <SCSIDataOutPDU> GetWriteData(SessionParameters session, ConnectionParameters connection, ushort LUN, ulong sectorIndex, byte[] data, int bytesPerSector, ReadyToTransferPDU readyToTransfer) { List <SCSIDataOutPDU> result = new List <SCSIDataOutPDU>(); // if readyToTransfer.DesiredDataTransferLength <= connection.TargetMaxRecvDataSegmentLength we must send multiple Data-Out PDUs // We assume DesiredDataTransferLength does not violate session.MaxBurstLength int numberOfChunks = (int)Math.Ceiling((double)readyToTransfer.DesiredDataTransferLength / connection.TargetMaxRecvDataSegmentLength); for (int chunkIndex = 0; chunkIndex < numberOfChunks; chunkIndex++) { int chunkOffset = chunkIndex * connection.TargetMaxRecvDataSegmentLength; int chunkLength = (int)Math.Min(connection.TargetMaxRecvDataSegmentLength, readyToTransfer.DesiredDataTransferLength - chunkOffset); SCSIDataOutPDU dataOut = new SCSIDataOutPDU(); dataOut.BufferOffset = readyToTransfer.BufferOffset + (uint)chunkOffset; dataOut.Data = ByteReader.ReadBytes(data, (int)dataOut.BufferOffset, chunkLength); dataOut.TargetTransferTag = readyToTransfer.TargetTransferTag; dataOut.InitiatorTaskTag = readyToTransfer.InitiatorTaskTag; if (chunkIndex == numberOfChunks - 1) { dataOut.Final = true; } result.Add(dataOut); } return(result); }
internal static List <ReadyToTransferPDU> GetReadyToTransferPDUs(SCSIDataOutPDU request, ConnectionParameters connection, out List <SCSICommandPDU> commandsToExecute) { List <ReadyToTransferPDU> responseList = new List <ReadyToTransferPDU>(); commandsToExecute = new List <SCSICommandPDU>(); ISCSISession session = connection.Session; TransferEntry transfer = connection.GetTransferEntry(request.TargetTransferTag); if (transfer == null) { throw new InvalidTargetTransferTagException(request.TargetTransferTag); } uint offset = request.BufferOffset; uint totalLength = (uint)transfer.Command.ExpectedDataTransferLength; // Store segment (we only execute the command after receiving all of its data) Array.Copy(request.Data, 0, transfer.Command.Data, offset, request.DataSegmentLength); if (offset + request.DataSegmentLength == totalLength) { // Last Data-out PDU connection.RemoveTransfer(request.TargetTransferTag); session.CommandsInTransfer.Remove(transfer.Command.CmdSN); if (session.IsPrecedingCommandPending(transfer.Command.CmdSN)) { session.DelayedCommands.Add(transfer.Command); } else { commandsToExecute.Add(transfer.Command); // Check if delayed commands are ready to be executed List <SCSICommandPDU> pendingCommands = session.GetDelayedCommandsReadyForExecution(); foreach (SCSICommandPDU pendingCommand in pendingCommands) { commandsToExecute.Add(pendingCommand); } } return(responseList); } else { // RFC 3720: An R2T MAY be answered with one or more SCSI Data-Out PDUs with a matching Target Transfer Tag. // If an R2T is answered with a single Data-Out PDU, the Buffer Offset in the Data PDU MUST be the same as the one specified // by the R2T, and the data length of the Data PDU MUST be the same as the Desired Data Transfer Length specified in the R2T. // If the R2T is answered with a sequence of Data PDUs, the Buffer Offset and Length MUST be within // the range of those specified by R2T, and the last PDU MUST have the F bit set to 1. // An R2T is considered outstanding until the last data PDU is transferred. if (request.Final) { // We already sent as many R2T as we could, we will only send R2T if any remained. if (transfer.NextR2TSN < transfer.TotalR2Ts) { // Send R2T ReadyToTransferPDU response = new ReadyToTransferPDU(); response.InitiatorTaskTag = request.InitiatorTaskTag; response.TargetTransferTag = request.TargetTransferTag; response.R2TSN = transfer.NextR2TSN; response.BufferOffset = transfer.NextOffset; // where we left off response.DesiredDataTransferLength = Math.Min((uint)connection.TargetMaxRecvDataSegmentLength, totalLength - response.BufferOffset); responseList.Add(response); transfer.NextR2TSN++; transfer.NextOffset += (uint)connection.TargetMaxRecvDataSegmentLength; } } return(responseList); } }
public void ProcessPDU(ISCSIPDU pdu, StateObject state) { Socket clientSocket = state.ClientSocket; uint?cmdSN = PDUHelper.GetCmdSN(pdu); Log(LogLevel.Debug, "[{0}][ProcessPDU] Received PDU from initiator, Operation: {1}, Size: {2}, CmdSN: {3}", state.ConnectionIdentifier, (ISCSIOpCodeName)pdu.OpCode, pdu.Length, cmdSN); // RFC 3720: On any connection, the iSCSI initiator MUST send the commands in increasing order of CmdSN, // except for commands that are retransmitted due to digest error recovery and connection recovery. if (cmdSN.HasValue) { if (state.SessionParameters.CommandNumberingStarted) { if (cmdSN != state.SessionParameters.ExpCmdSN) { Log(LogLevel.Warning, "[{0}][ProcessPDU] CmdSN outside of expected range", state.ConnectionIdentifier); // We ignore this PDU return; } } else { state.SessionParameters.ExpCmdSN = cmdSN.Value; state.SessionParameters.CommandNumberingStarted = true; } if (pdu is LogoutRequestPDU || pdu is TextRequestPDU || pdu is SCSICommandPDU || pdu is RejectPDU) { if (!pdu.ImmediateDelivery) { state.SessionParameters.ExpCmdSN++; } } } if (pdu is LoginRequestPDU) { LoginRequestPDU request = (LoginRequestPDU)pdu; Log(LogLevel.Information, "[{0}][ReceiveCallback] Login Request, current stage: {1}, next stage: {2}, parameters: {3}", state.ConnectionIdentifier, request.CurrentStage, request.NextStage, KeyValuePairUtils.ToString(request.LoginParameters)); if (request.TSIH != 0) { // RFC 3720: A Login Request with a non-zero TSIH and a CID equal to that of an existing // connection implies a logout of the connection followed by a Login lock (m_activeConnectionsLock) { int existingConnectionIndex = GetStateObjectIndex(m_activeConnections, request.ISID, request.TSIH, request.CID); if (existingConnectionIndex >= 0) { // Perform implicit logout Log(LogLevel.Information, "[{0}][ProcessPDU] Initiating implicit logout", state.ConnectionIdentifier); SocketUtils.ReleaseSocket(m_activeConnections[existingConnectionIndex].ClientSocket); if (m_activeConnections[existingConnectionIndex].Target != null) { lock (m_activeConnections[existingConnectionIndex].Target.IOLock) { // Wait for pending I/O to complete. } } m_activeConnections.RemoveAt(existingConnectionIndex); Log(LogLevel.Information, "[{0}][ProcessPDU] Implicit logout completed", state.ConnectionIdentifier); } } } LoginResponsePDU response = ServerResponseHelper.GetLoginResponsePDU(request, m_targets, state.SessionParameters, state.ConnectionParameters, ref state.Target, GetNextTSIH); if (state.SessionParameters.IsFullFeaturePhase) { state.SessionParameters.ISID = request.ISID; state.ConnectionParameters.CID = request.CID; lock (m_activeConnectionsLock) { m_activeConnections.Add(state); } } Log(LogLevel.Information, "[{0}][ReceiveCallback] Login Response parameters: {1}", state.ConnectionIdentifier, KeyValuePairUtils.ToString(response.LoginParameters)); TrySendPDU(state, response); } else if (!state.SessionParameters.IsFullFeaturePhase) { // Before the Full Feature Phase is established, only Login Request and Login Response PDUs are allowed. Log(LogLevel.Warning, "[{0}][ProcessPDU] Improper command during login phase, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); // A target receiving any PDU except a Login request before the Login phase is started MUST // immediately terminate the connection on which the PDU was received. // Once the Login phase has started, if the target receives any PDU except a Login request, // it MUST send a Login reject (with Status "invalid during login") and then disconnect. clientSocket.Dispose(); } else // Logged in { if (pdu is TextRequestPDU) { TextRequestPDU request = (TextRequestPDU)pdu; TextResponsePDU response = ServerResponseHelper.GetTextResponsePDU(request, m_targets); TrySendPDU(state, response); } else if (pdu is LogoutRequestPDU) { lock (m_activeConnectionsLock) { int connectionIndex = GetStateObjectIndex(m_activeConnections, state.SessionParameters.ISID, state.SessionParameters.TSIH, state.ConnectionParameters.CID); if (connectionIndex >= 0) { if (m_activeConnections[connectionIndex].Target != null) { lock (m_activeConnections[connectionIndex].Target.IOLock) { // Wait for pending I/O to complete. } } m_activeConnections.RemoveAt(connectionIndex); } } LogoutRequestPDU request = (LogoutRequestPDU)pdu; LogoutResponsePDU response = ServerResponseHelper.GetLogoutResponsePDU(request); TrySendPDU(state, response); clientSocket.Dispose(); // We can close the connection now } else if (state.SessionParameters.IsDiscovery) { // The target MUST ONLY accept text requests with the SendTargets key and a logout // request with the reason "close the session". All other requests MUST be rejected. Log(LogLevel.Warning, "[{0}][ProcessPDU] Improper command during discovery session, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); RejectPDU reject = new RejectPDU(); reject.Reason = RejectReason.ProtocolError; reject.Data = ByteReader.ReadBytes(pdu.GetBytes(), 0, 48); TrySendPDU(state, reject); } else if (pdu is NOPOutPDU) { NOPOutPDU request = (NOPOutPDU)pdu; if (request.InitiatorTaskTag != 0xFFFFFFFF) { NOPInPDU response = ServerResponseHelper.GetNOPResponsePDU(request); TrySendPDU(state, response); } } else if (pdu is SCSIDataOutPDU) { // FIXME: the iSCSI target layer MUST deliver the commands for execution (to the SCSI execution engin) in the order specified by CmdSN // e.g. read requests should not be executed while previous write request data is being received (via R2T) SCSIDataOutPDU request = (SCSIDataOutPDU)pdu; Log(LogLevel.Debug, "[{0}][ProcessPDU] SCSIDataOutPDU: Target transfer tag: {1}, LUN: {2}, Buffer offset: {3}, Data segment length: {4}, DataSN: {5}, Final: {6}", state.ConnectionIdentifier, request.TargetTransferTag, (ushort)request.LUN, request.BufferOffset, request.DataSegmentLength, request.DataSN, request.Final); ISCSIPDU response = TargetResponseHelper.GetSCSIDataOutResponsePDU(request, state.Target, state.SessionParameters, state.ConnectionParameters); TrySendPDU(state, response); } else if (pdu is SCSICommandPDU) { SCSICommandPDU command = (SCSICommandPDU)pdu; Log(LogLevel.Debug, "[{0}][ProcessPDU] SCSICommandPDU: CmdSN: {1}, LUN: {2}, Data segment length: {3}, Expected Data Transfer Length: {4}, Final: {5}", state.ConnectionIdentifier, command.CmdSN, (ushort)command.LUN, command.DataSegmentLength, command.ExpectedDataTransferLength, command.Final); List <ISCSIPDU> scsiResponseList = TargetResponseHelper.GetSCSIResponsePDU(command, state.Target, state.SessionParameters, state.ConnectionParameters); foreach (ISCSIPDU response in scsiResponseList) { TrySendPDU(state, response); if (!clientSocket.Connected) { return; } } } else { Log(LogLevel.Warning, "[{0}][ProcessPDU] Unsupported command, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); } } }
private void ProcessPDU(ISCSIPDU pdu, ConnectionState state) { LogTrace("Entering ProcessPDU"); if (state.Session == null || !state.Session.IsFullFeaturePhase) { if (pdu is LoginRequestPDU) { LoginRequestPDU request = (LoginRequestPDU)pdu; string loginIdentifier = String.Format("ISID={0},TSIH={1},CID={2}", request.ISID.ToString("x"), request.TSIH.ToString("x"), request.CID.ToString("x")); Log(Severity.Verbose, "[{0}] Login Request, current stage: {1}, next stage: {2}, parameters: {3}", loginIdentifier, request.CurrentStage, request.NextStage, FormatNullDelimitedText(request.LoginParametersText)); LoginResponsePDU response = GetLoginResponsePDU(request, state.ConnectionParameters); if (state.Session != null && state.Session.IsFullFeaturePhase) { m_connectionManager.AddConnection(state); } Log(Severity.Verbose, "[{0}] Login Response parameters: {1}", state.ConnectionIdentifier, FormatNullDelimitedText(response.LoginParametersText)); state.SendQueue.Enqueue(response); } else { // Before the Full Feature Phase is established, only Login Request and Login Response PDUs are allowed. Log(Severity.Warning, "[{0}] Initiator error: Improper command during login phase, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); if (state.Session == null) { // A target receiving any PDU except a Login request before the Login phase is started MUST // immediately terminate the connection on which the PDU was received. state.ClientSocket.Close(); } else { // Once the Login phase has started, if the target receives any PDU except a Login request, // it MUST send a Login reject (with Status "invalid during login") and then disconnect. LoginResponsePDU loginResponse = new LoginResponsePDU(); loginResponse.TSIH = state.Session.TSIH; loginResponse.Status = LoginResponseStatusName.InvalidDuringLogon; state.SendQueue.Enqueue(loginResponse); } } } else // Logged in { if (pdu is TextRequestPDU) { TextRequestPDU request = (TextRequestPDU)pdu; TextResponsePDU response = GetTextResponsePDU(request, state.ConnectionParameters); state.SendQueue.Enqueue(response); } else if (pdu is LogoutRequestPDU) { LogoutRequestPDU request = (LogoutRequestPDU)pdu; ISCSIPDU response = GetLogoutResponsePDU(request, state.ConnectionParameters); state.SendQueue.Enqueue(response); } else if (state.Session.IsDiscovery) { // The target MUST ONLY accept text requests with the SendTargets key and a logout // request with the reason "close the session". All other requests MUST be rejected. Log(Severity.Warning, "[{0}] Initiator error: Improper command during discovery session, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); RejectPDU reject = new RejectPDU(); reject.Reason = RejectReason.ProtocolError; reject.Data = ByteReader.ReadBytes(pdu.GetBytes(), 0, 48); state.SendQueue.Enqueue(reject); } else if (pdu is NOPOutPDU) { NOPOutPDU request = (NOPOutPDU)pdu; if (request.InitiatorTaskTag != 0xFFFFFFFF) { NOPInPDU response = ServerResponseHelper.GetNOPResponsePDU(request); state.SendQueue.Enqueue(response); } } else if (pdu is SCSIDataOutPDU || pdu is SCSICommandPDU) { // RFC 3720: the iSCSI target layer MUST deliver the commands for execution (to the SCSI execution engine) in the order specified by CmdSN. // e.g. read requests should not be executed while previous write request data is being received (via R2T) List <SCSICommandPDU> commandsToExecute = null; List <ReadyToTransferPDU> readyToTransferPDUs = new List <ReadyToTransferPDU>(); if (pdu is SCSIDataOutPDU) { SCSIDataOutPDU request = (SCSIDataOutPDU)pdu; Log(Severity.Debug, "[{0}] SCSIDataOutPDU: Target transfer tag: {1}, LUN: {2}, Buffer offset: {3}, Data segment length: {4}, DataSN: {5}, Final: {6}", state.ConnectionIdentifier, request.TargetTransferTag, (ushort)request.LUN, request.BufferOffset, request.DataSegmentLength, request.DataSN, request.Final); try { readyToTransferPDUs = TargetResponseHelper.GetReadyToTransferPDUs(request, state.ConnectionParameters, out commandsToExecute); } catch (InvalidTargetTransferTagException ex) { Log(Severity.Warning, "[{0}] Initiator error: Invalid TargetTransferTag: {1}", state.ConnectionIdentifier, ex.TargetTransferTag); RejectPDU reject = new RejectPDU(); reject.InitiatorTaskTag = request.InitiatorTaskTag; reject.Reason = RejectReason.InvalidPDUField; reject.Data = ByteReader.ReadBytes(request.GetBytes(), 0, 48); state.SendQueue.Enqueue(reject); } } else { SCSICommandPDU command = (SCSICommandPDU)pdu; Log(Severity.Debug, "[{0}] SCSICommandPDU: CmdSN: {1}, LUN: {2}, Data segment length: {3}, Expected Data Transfer Length: {4}, Final: {5}", state.ConnectionIdentifier, command.CmdSN, (ushort)command.LUN, command.DataSegmentLength, command.ExpectedDataTransferLength, command.Final); readyToTransferPDUs = TargetResponseHelper.GetReadyToTransferPDUs(command, state.ConnectionParameters, out commandsToExecute); } foreach (ReadyToTransferPDU readyToTransferPDU in readyToTransferPDUs) { state.SendQueue.Enqueue(readyToTransferPDU); } if (commandsToExecute != null) { state.RunningSCSICommands.Add(commandsToExecute.Count); } foreach (SCSICommandPDU commandPDU in commandsToExecute) { Log(Severity.Debug, "[{0}] Queuing command: CmdSN: {1}", state.ConnectionIdentifier, commandPDU.CmdSN); state.Target.QueueCommand(commandPDU.CommandDescriptorBlock, commandPDU.LUN, commandPDU.Data, commandPDU, state.OnCommandCompleted); } } else if (pdu is LoginRequestPDU) { Log(Severity.Warning, "[{0}] Initiator Error: Login request during full feature phase", state.ConnectionIdentifier); // RFC 3720: Login requests and responses MUST be used exclusively during Login. // On any connection, the login phase MUST immediately follow TCP connection establishment and // a subsequent Login Phase MUST NOT occur before tearing down a connection RejectPDU reject = new RejectPDU(); reject.Reason = RejectReason.ProtocolError; reject.Data = ByteReader.ReadBytes(pdu.GetBytes(), 0, 48); state.SendQueue.Enqueue(reject); } else { Log(Severity.Error, "[{0}] Unsupported command, OpCode: 0x{1}", state.ConnectionIdentifier, pdu.OpCode.ToString("x")); RejectPDU reject = new RejectPDU(); reject.Reason = RejectReason.CommandNotSupported; reject.Data = ByteReader.ReadBytes(pdu.GetBytes(), 0, 48); state.SendQueue.Enqueue(reject); } } LogTrace("Leaving ProcessPDU"); }