ftpserver.java

一个非常好的ssh客户端实现

		    }
		    case CMD_SYST:
			reply(215, eventHandler.system());
			break;
		    case CMD_NOOP:
			reply(200, "NOOP command successful.");
			break;
		    case CMD_FEAT:
			reply(211, "Extensions supported:\nSIZE\nMDTM\nEND");
			break;
		    case CMD_MDTM:
			checkArgAndPlainFile(argv);
			long modt = eventHandler.modTime(argv[1]);
			SimpleDateFormat df =
			    new SimpleDateFormat("yyyyMMddhhmmss");
			reply(213, df.format(new Date(modt)));
			break;
		    case CMD_SIZE:
			checkArgAndPlainFile(argv);
			long size = eventHandler.size(argv[1]);
			reply(213, String.valueOf(size));
			break;
		    case CMD_PASS:
			/*
			 * Allow buggy clients to send PASS eventhough they are
			 * logged in (e.g. dreamweaver it seems)
			 */
			reply(230, "User " + user + " logged in.");
			break;
		    case CMD_HELP:
		    case CMD_STAT:
		    case CMD_SITE:
		    case CMD_USER:
		    case CMD_ACCT:
		    case CMD_SMNT:
		    case CMD_REIN:
		    case CMD_STRU:
		    case CMD_MODE:
		    case CMD_STOU:
		    case CMD_APPE:
		    case CMD_ALLO:
		    case CMD_REST:
			reply(502, "'" + argv[0] +
			      "': command not implemented");
			break;
		    case CMD_UNKN:
			reply(500, "'" + argv[0] + "': command not understood");
			break;
		    }
		} catch (FTPException e) {
		    if(dataConnected) {
			dataReset();
		    }
		    reply(e.getCode(), e.getMessage());
		}
	    }

	} catch (IOException e) {
	    // !!! TODO eventhandler.error ...
	} finally {
	    try { cmdOutput.close(); }
	    catch (IOException e) { /* don't care */ }
	    try { cmdInput.close(); }
	    catch (IOException e) { /* don't care */ }
	    // !!! TODO other clean up ???
	}
    }

    public void terminate() {
	try { cmdOutput.close(); }
	catch (IOException e) { /* don't care */ }
	try { cmdInput.close(); }
	catch (IOException e) { /* don't care */ }
    }

    private void checkArgAndPlainFile(String[] argv)
	throws FTPException
    {
	if(argv.length < 2 || argv[1] == null) {
	    throw new FTPException(500, "'" + argv[0] +
				   "': command not understood");
	}
	if(!eventHandler.isPlainFile(argv[1])) {
	    throw new FTPException(550, argv[1] + ": Not a plain file.");
	}
    }

    private int readCommand(String[] argv) throws IOException {
	String cmdLine = cmdInput.readLine();
	if(cmdLine == null) {
	    // !!! TODO
	    throw new EOFException();
	}

	int i = cmdLine.indexOf(' ');
	if(i != -1) {
	    argv[0] = cmdLine.substring(0, i);
	    argv[1] = cmdLine.substring(i + 1);
	} else {
	    argv[0] = cmdLine.trim();
	    argv[1] = null;
	}

	argv[0] = argv[0].toUpperCase();
	Integer code = (Integer)commands.get(argv[0]);

	if(DEBUG) System.out.println("ftp cmd: " + argv[0] + " " + argv[1]);

	if(code == null) {
	    return -1;
	}
	return code.intValue();
    }

    public void reply(int code, String text) throws IOException {
	String msg;

	if(DEBUG) System.out.println("ftp reply: " + code + " " + text);

	if(text.indexOf('\n') != -1) {
	    msg = code + "-";
	    StringTokenizer st = new StringTokenizer(text, "\r\n");
	    while(st.hasMoreTokens()) {
		String line = st.nextToken();
		if(st.hasMoreTokens()) {
		    msg += " " + line + "\r\n";
		} else {
		    msg += code + " " + line + "\r\n";
		}
	    }
	} else {
	    msg = code + " " + text + "\r\n";
	}
	cmdOutput.write(msg.getBytes());
    }

    public void readLogin() throws IOException {
	user     = null;
	password = null;
	while(user == null || password == null) {
	    String[] argv = new String[2];
	    int code = readCommand(argv);
	    if(code == CMD_USER) {
		user = argv[1];
		if(user != null) {
		    if(needPassword) {
			reply(331, "Password required for " + user + ".");
			continue;
		    } else {
			return;
		    }
		}
	    } else if(code == CMD_PASS && user != null) {
		password = argv[1];
	    }
	    if(password == null) {
		reply(530, "Please login with USER and PASS.");
	    }
	}
    }

    protected int[] dataPort(String arg) throws FTPException {
	dataReset();
	StringTokenizer st = new StringTokenizer(arg, ",");
	int i = 0;
	int[] d = new int[6];
	while(i < 6 && st.hasMoreTokens()) {
	    try {
		d[i++] = Integer.parseInt(st.nextToken());
	    } catch (NumberFormatException e) {
		throw new FTPException(500, "'PORT " + arg +
				       "': command not understood");
	    }
	}
	if(i < 6) {
	    throw new FTPException(500, "'PORT " + arg +
				   "': command not understood");
	}
	return d;
    }

    protected String dataPassive() throws FTPException {
	dataReset();

	try {
	    dataPasvAccept = new ServerSocket(0, 16, localHost);
	    dataPasvAccept.setSoTimeout(30000);
	} catch (Exception e) {
	    dataReset();
	    throw new FTPException(500, "Error, unable to proceede: " +
				   e.getMessage());
	}

	byte[] localAddrArr = null;
	localAddrArr        = localHost.getAddress();
	// !!! TODO: want to be able to get actual connected adress
	if((localAddrArr[0] & 0xff) == 0) {
	    try {
		localAddrArr = InetAddress.getLocalHost().getAddress();
	    } catch (UnknownHostException e) {
		throw new Error("Error in FTPServer: " + e);
	    }
	}
	int a1 = localAddrArr[0] & 0xff;
	int a2 = localAddrArr[1] & 0xff;
	int a3 = localAddrArr[2] & 0xff;
	int a4 = localAddrArr[3] & 0xff;

	int port = dataPasvAccept.getLocalPort();
	int p1 = (port >>> 8) & 0xff;
	int p2 = port & 0xff;

	return a1 + "," + a2 + "," + a3 + "," + a4 + "," + p1 + "," + p2;
    }

    protected OutputStream getDataOutput() throws FTPException {
	dataConnect();
	if(dataSocket == null) {
	    throw new FTPException(550, "Error when making data connection.");
	}
	try {
	    dataOut = dataSocket.getOutputStream();
	    return dataOut;
	} catch (IOException e) {
	    throw new FTPException(425, "Can't build data connection: " +
				   e.getMessage());
	}
    }

    protected InputStream getDataInput() throws FTPException {
	dataConnect();
	try {
	    dataIn = dataSocket.getInputStream();
	    return dataIn;
	} catch (IOException e) {
	    throw new FTPException(425, "Can't build data connection: " +
				   e.getMessage());
	}
    }

    protected void dataConnect() throws FTPException {
	try {
	    if(dataPasvAccept != null) {
		dataSocket = dataPasvAccept.accept();
	    } else if(dataPortAddr != null) {
		String toHost = dataPortAddr[0] + "." + dataPortAddr[1] + "." +
		    dataPortAddr[2] + "." + dataPortAddr[3];
		int    toPort = (dataPortAddr[4] << 8) | dataPortAddr[5];
		dataSocket = new Socket(toHost, toPort);
	    }
	    dataConnected = true;
	} catch (IOException e) {
	    dataReset();
	    throw new FTPException(425, "Can't build data connection: " +
				   e.getMessage());
	}
    }

    protected void dataStart(String obj) throws IOException {
	reply(150, "Opening " +
	      (type.equals("A") ? "ASCII" : "BINARY") +
	      " mode data connection for " + obj + ".");
    }

    protected void dataComplete() throws IOException {
	reply(226, "Transfer complete.");
	dataReset();
    }

    protected void dataReset() {
	if(dataPasvAccept != null) {
	    try { dataPasvAccept.close(); }
	    catch (Exception e) { /* don't care */ }
	    dataPasvAccept = null;
	}
	dataPortAddr = null;
	if(dataSocket != null) {
	    try { if(dataOut != null) dataOut.close();
	    } catch (IOException e) { /* don't care */ }
	    try { if(dataIn != null) dataIn.close();
	    } catch (IOException e) { /* don't care */ }
	    try { dataSocket.close(); }
	    catch (Exception e) { /* don't care */ }
	}
	dataSocket    = null;
	dataOut       = null;
	dataIn        = null;
	dataConnected = false;
    }

}