ftpserversocket.java

JAVA FTP客户端经典

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
package net.sf.jftp.net;

import java.io.*;
import java.lang.reflect.*;
import java.net.*;
import java.text.*;
import java.util.*;
import net.sf.jftp.util.Log;

/**
 *
 */
public class FtpServerSocket extends Thread
{
    public final static int port = 21;
    public final static int dataPort = 20;
    private Socket socket = null;
    private BufferedReader in = null;
    private PrintWriter out = null;
    private Hashtable methods = new Hashtable();
    private File directory = new File(".");
    private ResourceBundle bundle = ResourceBundle.getBundle("responses", Locale.US); 
    private ServerSocket pasvSocket = null;
    private boolean passive = false;
    private int activePort = 0;
    private String structure = "file";
    private String transferMode = "stream";
    private String type = "ascii"; 
    private static ArrayList commands = null;
    private String rootDir = null;
    private String currentDir = null;
    
    static {
        commands = new ArrayList();
        commands.add("auth");
        commands.add("cdup");
        commands.add("cwd");
        commands.add("feat");
        commands.add("help");
        commands.add("lang");
        commands.add("list");
        commands.add("mkd");
        commands.add("mode");
        commands.add("motd");
        commands.add("nlst");
        commands.add("noop");
        commands.add("opts");
        commands.add("pass");
        commands.add("pasv");
        commands.add("port");
        commands.add("pwd");
        commands.add("quit");
        commands.add("rein");
        commands.add("smnt");
        commands.add("stat");
        commands.add("stru");
        commands.add("syst");
        commands.add("type");
        commands.add("user");
    }
    
    public FtpServerSocket(Socket s) throws IOException
    {
        socket = s;
        try {
            in = new BufferedReader( new InputStreamReader(socket.getInputStream()) );
            out = new PrintWriter(socket.getOutputStream(), true);
        } catch (IOException ioe) { throw ioe; }
        Method[] m = this.getClass().getDeclaredMethods();
        String methodName = null;
        for (int i = 0; i < m.length; i++) {
            methodName = m[i].getName();
            if (commands.contains(methodName))
                methods.put(methodName, m[i]);
        }
        this.start();
    }

    private void send(String bundleId) {
        out.print( bundle.getString(bundleId));
        out.flush();
    }

    private void send(String bundleId, Object[] args) {
        MessageFormat fmt = new MessageFormat(bundle.getString(bundleId));
        out.print(fmt.format(args));
        out.flush();
    }

    public void motd()
    {
        send("220motd");
    }

    public void user(String line)
    {
        send("331user");
    }

    public void pass(String line)
    {
        send("230pass");
    }

    public void syst(String line)
    {
        send("215syst");
    }

    public void type(String line)
    { // needs work A, E, I, L, C, T, N
        Object [] args = { "I" };
        send("200type", args);
    }

    public void stru(String line)
    { // needs work - check for F, R, or P
        Object [] args = { line.toUpperCase() };
        send("200ok", args);
    }

    public void mode(String line)
    { // check for S, B, or C
        Object [] args = { line.toUpperCase() };
        send("200ok", args);
    }

    public void rein(String line)
    {
        Object [] args = { "REIN" };
        send("502", args);
    }

    public void smnt(String line)
    {
        Object [] args = { "SMNT" };
        send("502", args);
    }

    public void quit(String line)
    {
        out.print("221-You have transferred 0 bytes in 0 files.\r\n");
        out.print("221-Total traffic for this session was 0 bytes in 0 transfers.\r\n");
        out.print("221 Thank you for using the FTP service on pikachu.\r\n");
        out.flush();
        try {
        socket.close();
        } catch (Exception e) {}
    }

    public void pwd(String line)
    {
        Object[] args = { currentDir };
        send("257pwd", args);
    }

    public void cwd(String line)
    {
        String arg = line.substring(4);
        String tmpDir;
        if (arg.startsWith("/"))
            tmpDir = removeTrailingSlash(rootDir) + arg;
        else
            tmpDir = addTrailingSlash(currentDir) + arg;
        File tmp = new File(tmpDir);
        if (tmp.exists() && tmp.isDirectory()) {
            currentDir = tmpDir;
            send("250cwd");
        } else {
            out.print("550 " + arg + ": No such file or directory.\r\n");
            out.flush();
        }
    }

    public void cdup(String line)
    {
        Object[] args = { "CDUP" };
        File tmp = directory.getParentFile();
        if (tmp != null) {
            directory = tmp;
        }
        send("200", args);
    }

    public void noop(String line)
    {
        Object[] args = { "NOOP" };
        send("200", args);
    }

    public void help(String line)
    {  
        out.print("214-The following commands are recognized.\r\n");
/*
   USER    PORT    STOR    RNTO    NLST    MKD     CDUP 
   PASS    PASV    APPE    ABOR    SITE    XMKD    XCUP 
   TYPE    DELE    SYST    RMD     STOU 
   STRU    ALLO    CWD     STAT    XRMD    SIZE 
   MODE    REST    XCWD    HELP    PWD     MDTM 
   QUIT    RETR    RNFR    LIST    NOOP    XPWD 
*/
        out.print("214 Direct comments to root@localhost.\r\n");
        out.flush();
    }

    public void stat(String line)
    {  
        out.print("211-FTP server status:\r\n");
/*
     Version wu-2.6.1-16
     Connected to pikachu (127.0.0.1)
     Logged in as gary
     TYPE: ASCII, FORM: Nonprint; STRUcture: File; transfer MODE: Stream
     No data connection
     0 data bytes received in 0 files
     0 data bytes transmitted in 0 files
     0 data bytes total in 0 files
     82 traffic bytes received in 0 transfers
     2502 traffic bytes transmitted in 1 transfers
     2634 traffic bytes total in 1 transfers
     Disk quota: 0 disk blocks in use, 0 quota, 0 limit - time left
     Inode quota: 0 inodes in use, 0 quota, 0 limit - time left
*/
        out.print("211 End of status\r\n");
        out.flush();
    }
    
    private String addTrailingSlash(String s)
    {
        if (s.endsWith("/"))
            return s;
        else
            return s + "/";
    }

    private String removeTrailingSlash(String s)
    {
        if (s.endsWith("/"))
            return s.substring(0, s.length() - 1);
        else
            return s;
    }
    
    public void mkd(String line)
    {
        String arg = line.substring(4);
        if (arg.startsWith("/"))
            arg = removeTrailingSlash(rootDir) + arg;
        else
            arg = addTrailingSlash(currentDir) + arg;
        File f = new File(arg);
        MessageFormat fmt = null;
        Object[] args = { f.getAbsolutePath() };
        if (f.exists()) {
            send("521mkd", args);
        } else if (f.mkdirs()) {
            send("257mkd", args);
        } else
            send("550mkd", args);
    }

    public void feat(String line)
    {
       out.print("211-Extensions supported\r\n");
       out.print(" LANG EN*;FR\r\n");
       out.print("211 END\r\n");
       out.flush();
    }

    public void pasv(String line)
    {
        InetAddress address = socket.getLocalAddress();
        String pasvAddress = address.getHostAddress().replace('.', ',');
        try {
        pasvSocket = new ServerSocket(0, 5, address);
        passive = true;
        } catch (IOException ioe) {}
        int pasvPort = pasvSocket.getLocalPort();
        Object[] args = { pasvAddress + "," + (int)pasvPort / 256 + "," + pasvPort % 256};
        send("227pasv", args);
    }

    public void list(String line)
    {
        send("150list");
        if (!passive) {
try {
            Socket activeSocket = new Socket(socket.getInetAddress(), activePort);
            PrintStream ps = new PrintStream(activeSocket.getOutputStream());
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.flush();
            ps.close();
            send("226");
} catch (Exception e) {}
        }
    }

    public void nlst(String line)
    {
        send("150nlst");
        if (!passive) {
try {
            Socket activeSocket = new Socket(socket.getInetAddress(), activePort);
            PrintStream ps = new PrintStream(activeSocket.getOutputStream());
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.print("bleah\r\n");
            ps.flush();
            ps.close();
            send("225");
} catch (Exception e) {}
        }
    }

    public void port(String line)
    {
        int start = line.lastIndexOf(",");
        int end = line.length();
        String lo = null; // lo-ordered byte
        if (start != -1 && end != -1)
            lo = line.substring(start + 1, end);
        end = start;
        start = line.lastIndexOf(",", start - 1);
        String hi = null; // hi-ordered byte
        if (start != -1 && end != -1)
            hi = line.substring(start + 1, end);

        activePort = (Integer.parseInt(hi) * 256 + Integer.parseInt(lo));
        Object[] args = { "PORT" };
        send("200", args);
    }

    public void opts(String line)
    {
// return 200, 451 or 501
    }

    public void lang(String line)
    {
        out.print("200 Responses changed to english\r\n");
        out.flush();
    }

    public void auth(String line)
    {
    }
    
    public void setRoot(String line)
    {
        if (new File(line).exists())
            rootDir = line;
        else
            System.err.println("invalid root directory");
    }

    public void run()
    {
        try
        {
            String line = null;
            motd();
            while ((line = in.readLine()) != null) {
                System.out.println( line );
                int index = line.indexOf(' ');
                if (index == -1)
                    index = line.length();
                String command = line.substring(0, index).toLowerCase();
                Method o = (Method)methods.get(command);
                if (o != null)
                {
                     try {
                     o.invoke(this, new Object[] { line }); 
                     } catch (Exception e) {}
                }
                else {
                    send("500");
                }
            }
        } catch (IOException ioe) {
            Log.debug("Socket error: " + ioe);
        }
    }

    public static void main(String[] args)
    {
    }
}