/* Copyright (C) 2017 Tal Aloni . All rights reserved. * * You can redistribute this program and/or modify it under the terms of * the GNU Lesser Public License as published by the Free Software Foundation, * either version 3 of the License, or (at your option) any later version. */ using System; using System.Collections.Generic; using SMBLibrary.NetBios; using SMBLibrary.Server.SMB2; using SMBLibrary.SMB2; using Utilities; namespace SMBLibrary.Server { public partial class SMBServer { // Key is the persistent portion of the FileID private Dictionary m_globalOpenFiles = new Dictionary(); private static ulong m_nextPersistentFileID = 1; // A numeric value that uniquely identifies the open handle to a file or a pipe within the scope of all opens granted by the server private ulong? AllocatePersistentFileID() { for (ulong offset = 0; offset < UInt64.MaxValue; offset++) { ulong persistentID = (ulong)(m_nextPersistentFileID + offset); if (persistentID == 0 || persistentID == 0xFFFFFFFFFFFFFFFF) { continue; } if (!m_globalOpenFiles.ContainsKey(persistentID)) { m_nextPersistentFileID = (ulong)(persistentID + 1); return persistentID; } } return null; } public void ProcessSMB2RequestChain(List requestChain, ref ConnectionState state) { List responseChain = new List(); FileID? fileID = null; foreach (SMB2Command request in requestChain) { if (request.Header.IsRelatedOperations && fileID.HasValue) { SetRequestFileID(request, fileID.Value); } SMB2Command response = ProcessSMB2Command(request, ref state); if (response != null) { UpdateSMB2Header(response, request); responseChain.Add(response); if (!request.Header.IsRelatedOperations) { fileID = GetResponseFileID(response); } } } if (responseChain.Count > 0) { TrySendResponseChain(state, responseChain); } } /// /// May return null /// public SMB2Command ProcessSMB2Command(SMB2Command command, ref ConnectionState state) { if (state.ServerDialect == SMBDialect.NotSet) { if (command is NegotiateRequest) { NegotiateRequest request = (NegotiateRequest)command; SMB2Command response = NegotiateHelper.GetNegotiateResponse(request, m_securityProvider, state, m_serverGuid); if (state.ServerDialect != SMBDialect.NotSet) { state = new SMB2ConnectionState(state, AllocatePersistentFileID); } return response; } else { // [MS-SMB2] If the request being received is not an SMB2 NEGOTIATE Request [..] // and Connection.NegotiateDialect is 0xFFFF or 0x02FF, the server MUST // disconnect the connection. state.LogToServer(Severity.Debug, "Invalid Connection State for command {0}", command.CommandName.ToString()); state.ClientSocket.Close(); return null; } } else if (command is NegotiateRequest) { // [MS-SMB2] If Connection.NegotiateDialect is 0x0202, 0x0210, 0x0300, 0x0302, or 0x0311, // the server MUST disconnect the connection. state.LogToServer(Severity.Debug, "Rejecting NegotiateRequest. NegotiateDialect is already set"); state.ClientSocket.Close(); return null; } else { return ProcessSMB2Command(command, (SMB2ConnectionState)state); } } public SMB2Command ProcessSMB2Command(SMB2Command command, SMB2ConnectionState state) { if (command is SessionSetupRequest) { return SessionSetupHelper.GetSessionSetupResponse((SessionSetupRequest)command, m_securityProvider, state); } else if (command is EchoRequest) { return new EchoResponse(); } else { SMB2Session session = state.GetSession(command.Header.SessionID); if (session == null) { return new ErrorResponse(command.CommandName, NTStatus.STATUS_USER_SESSION_DELETED); } if (command is TreeConnectRequest) { return TreeConnectHelper.GetTreeConnectResponse((TreeConnectRequest)command, state, m_services, m_shares); } else if (command is LogoffRequest) { m_securityProvider.DeleteSecurityContext(ref session.SecurityContext.AuthenticationContext); state.RemoveSession(command.Header.SessionID); return new LogoffResponse(); } else { ISMBShare share = session.GetConnectedTree(command.Header.TreeID); if (share == null) { return new ErrorResponse(command.CommandName, NTStatus.STATUS_NETWORK_NAME_DELETED); } if (command is TreeDisconnectRequest) { session.RemoveConnectedTree(command.Header.TreeID); return new TreeDisconnectResponse(); } else if (command is CreateRequest) { return CreateHelper.GetCreateResponse((CreateRequest)command, share, state); } else if (command is QueryInfoRequest) { return QueryInfoHelper.GetQueryInfoResponse((QueryInfoRequest)command, share, state); } else if (command is SetInfoRequest) { return SetInfoHelper.GetSetInfoResponse((SetInfoRequest)command, share, state); } else if (command is QueryDirectoryRequest) { return QueryDirectoryHelper.GetQueryDirectoryResponse((QueryDirectoryRequest)command, share, state); } else if (command is ReadRequest) { return ReadWriteResponseHelper.GetReadResponse((ReadRequest)command, share, state); } else if (command is WriteRequest) { return ReadWriteResponseHelper.GetWriteResponse((WriteRequest)command, share, state); } else if (command is FlushRequest) { FlushRequest request = (FlushRequest)command; OpenFileObject openFile = session.GetOpenFileObject(request.FileId.Persistent); if (openFile == null) { return new ErrorResponse(request.CommandName, NTStatus.STATUS_FILE_CLOSED); } NTStatus status = share.FileStore.FlushFileBuffers(openFile.Handle); if (status != NTStatus.STATUS_SUCCESS) { return new ErrorResponse(request.CommandName, status); } return new FlushResponse(); } else if (command is CloseRequest) { return CloseHelper.GetCloseResponse((CloseRequest)command, share, state); } else if (command is IOCtlRequest) { return IOCtlHelper.GetIOCtlResponse((IOCtlRequest)command, share, state); } else if (command is ChangeNotifyRequest) { // [MS-SMB2] If the underlying object store does not support change notifications, the server MUST fail this request with STATUS_NOT_SUPPORTED return new ErrorResponse(command.CommandName, NTStatus.STATUS_NOT_SUPPORTED); } } } return new ErrorResponse(command.CommandName, NTStatus.STATUS_NOT_SUPPORTED); } public static void TrySendResponse(ConnectionState state, SMB2Command response) { SessionMessagePacket packet = new SessionMessagePacket(); packet.Trailer = response.GetBytes(); TrySendPacket(state, packet); state.LogToServer(Severity.Verbose, "SMB2 response sent: {0}, Packet length: {1}", response.CommandName.ToString(), packet.Length); } public static void TrySendResponseChain(ConnectionState state, List responseChain) { SessionMessagePacket packet = new SessionMessagePacket(); packet.Trailer = SMB2Command.GetCommandChainBytes(responseChain); TrySendPacket(state, packet); state.LogToServer(Severity.Verbose, "SMB2 response chain sent: Response count: {0}, First response: {1}, Packet length: {2}", responseChain.Count, responseChain[0].CommandName.ToString(), packet.Length); } private static void UpdateSMB2Header(SMB2Command response, SMB2Command request) { response.Header.MessageID = request.Header.MessageID; response.Header.CreditCharge = request.Header.CreditCharge; response.Header.Credits = Math.Max((ushort)1, request.Header.Credits); response.Header.IsRelatedOperations = request.Header.IsRelatedOperations; response.Header.Reserved = request.Header.Reserved; if (response.Header.SessionID == 0) { response.Header.SessionID = request.Header.SessionID; } if (response.Header.TreeID == 0) { response.Header.TreeID = request.Header.TreeID; } } private static void SetRequestFileID(SMB2Command command, FileID fileID) { if (command is ChangeNotifyRequest) { ((ChangeNotifyRequest)command).FileId = fileID; } else if (command is CloseRequest) { ((CloseRequest)command).FileId = fileID; } else if (command is FlushRequest) { ((FlushRequest)command).FileId = fileID; } else if (command is IOCtlRequest) { ((IOCtlRequest)command).FileId = fileID; } else if (command is LockRequest) { ((LockRequest)command).FileId = fileID; } else if (command is QueryDirectoryRequest) { ((QueryDirectoryRequest)command).FileId = fileID; } else if (command is QueryInfoRequest) { ((QueryInfoRequest)command).FileId = fileID; } else if (command is ReadRequest) { ((ReadRequest)command).FileId = fileID; } else if (command is SetInfoRequest) { ((SetInfoRequest)command).FileId = fileID; } else if (command is WriteRequest) { ((WriteRequest)command).FileId = fileID; } } private static FileID? GetResponseFileID(SMB2Command command) { if (command is CreateResponse) { return ((CreateResponse)command).FileId; } else if (command is IOCtlResponse) { return ((IOCtlResponse)command).FileId; } return null; } } }