proxyloginhandler.java

这是一个基于java编写的torrent的P2P源码

  
  
  private void parseSocks4Reply( ByteBuffer reply ) throws IOException {
      byte ver = reply.get();
      byte resp = reply.get();

      if( ver != 0 || resp != 90 ) {
        throw new IOException( "SOCKS 4(a): connection declined [" +ver+ "/" + resp + "]" );
      }
  }
  
  
  
  

  private void sendMessage( ByteBuffer msg ) throws IOException {
    long start_time = SystemTime.getCurrentTime();
    
    while( msg.hasRemaining() ) {
      if( proxy_connection.write( new ByteBuffer[]{ msg }, 0, 1 ) < 1 ) {
        if( SystemTime.getCurrentTime() - start_time > 30*1000 ) {
          String error = "proxy handshake message send timed out after 30sec";
          Debug.out( error );
          throw new IOException( error );
        }
        
        try {   Thread.sleep( 10 );   }catch( Throwable t ) {t.printStackTrace();}
      }
    }
  }
  
  
  
  private int readMessage( ByteBuffer msg ) throws IOException {
    if( read_start_time == 0 )  read_start_time = SystemTime.getCurrentTime();
    
    long bytes_read = proxy_connection.read( new ByteBuffer[]{ msg }, 0, 1 );
    
    if( !msg.hasRemaining() ) {
      msg.position( 0 );
      read_start_time = 0;  //reset for next round
      return READ_DONE;
    }

    if( SystemTime.getCurrentTime() - read_start_time > 30*1000 ) {
      String error = "proxy message read timed out after 30sec";
      Debug.out( error );
      throw new IOException( error );
    }
    
    return( bytes_read==0?READ_NO_PROGRESS:READ_NOT_DONE);
  }
  
  
  
  
  private ByteBuffer[] createSocks4Message() throws Exception {
    ByteBuffer handshake = ByteBuffer.allocate( 256 + mapped_ip.length() );   //TODO convert to direct?

    handshake.put( (byte)4 ); // socks 4(a)
    handshake.put( (byte)1 ); // command = CONNECT
    handshake.putShort( (short)remote_address.getPort() );

    byte[] ip_bytes = HostNameToIPResolver.syncResolve( remote_address.getAddress().getHostAddress() ).getAddress();

    handshake.put( ip_bytes[ 0 ] );
    handshake.put( ip_bytes[ 1 ] );
    handshake.put( ip_bytes[ 2 ] );
    handshake.put( ip_bytes[ 3 ] );
    
    if( socks_user.length() > 0 ) {
      handshake.put( socks_user.getBytes() );
    }

    handshake.put( (byte)0 );
    
    handshake.flip();
   
    return new ByteBuffer[] { handshake, ByteBuffer.allocate( 8 ) };     //TODO convert to direct?
  }
  
  
  
  private ByteBuffer[] createSocks4aMessage() {
    ByteBuffer handshake = ByteBuffer.allocate( 256 + mapped_ip.length() );   //TODO convert to direct?

    handshake.put( (byte)4 ); // socks 4(a)
    handshake.put( (byte)1 ); // command = CONNECT
    handshake.putShort( (short)remote_address.getPort() ); // port
    handshake.put( (byte)0 );
    handshake.put( (byte)0 );
    handshake.put( (byte)0 );
    handshake.put( (byte)1 ); // indicates socks 4a

    if( socks_user.length() > 0 ) {
      handshake.put( socks_user.getBytes() );
    }

    handshake.put( (byte)0 );
    handshake.put( mapped_ip.getBytes() );
    handshake.put( (byte)0 );

    handshake.flip();
     
    return new ByteBuffer[] { handshake, ByteBuffer.allocate( 8 ) };   //TODO convert to direct?
  }
  
  
   
  
  private ByteBuffer[] createSocks5Message() {
    ByteBuffer handshake = ByteBuffer.allocate( 256 + mapped_ip.length() );   //TODO convert to direct?

    if( socks5_handshake_phase == 0 ) {  // say hello
      //System.out.println( "socks5 write phase 0" );
      
      handshake.put( (byte)5 ); // socks 5
      handshake.put( (byte)2 ); // 2 methods
      handshake.put( (byte)0 ); // no auth
      handshake.put( (byte)2 ); // user/pw

      handshake.flip();
      socks5_handshake_phase = 1;

      return new ByteBuffer[] { handshake, ByteBuffer.allocate( 2 ) };   //TODO convert to direct?
    }
    
    if( socks5_handshake_phase == 1 ) {  // user/password auth
      //System.out.println( "socks5 write phase 1" );
      
      handshake.put( (byte)1 ); // user/pw version
      handshake.put( (byte)socks_user.length() ); // user length
      handshake.put( socks_user.getBytes() );
      handshake.put( (byte)socks_password.length() ); // password length
      handshake.put( socks_password.getBytes() );

      handshake.flip();
      socks5_handshake_phase = 2;

      return new ByteBuffer[] { handshake, ByteBuffer.allocate( 2 ) };   //TODO convert to direct?
    }
    
    if( socks5_handshake_phase == 2 ) {  // request
      //System.out.println( "socks5 write phase 2" );
      
      handshake.put( (byte)5 ); // version
      handshake.put( (byte)1 ); // connect
      handshake.put( (byte)0 ); // reserved

      // use the maped ip for dns resolution so we don't leak the
      // actual address if this is a secure one (e.g. I2P one)
      try {
        byte[] ip_bytes = HostNameToIPResolver.syncResolve( mapped_ip ).getAddress();

        handshake.put( (byte)1 ); // IP4

        handshake.put( ip_bytes[ 0 ] );
        handshake.put( ip_bytes[ 1 ] );
        handshake.put( ip_bytes[ 2 ] );
        handshake.put( ip_bytes[ 3 ] );

      }
      catch (Throwable e) {
        handshake.put( (byte)3 );  // address type = domain name
        handshake.put( (byte)mapped_ip.length() );  // address type = domain name
        handshake.put( mapped_ip.getBytes() );
      }

      handshake.putShort( (short)remote_address.getPort() ); // port
      
      handshake.flip();
      socks5_handshake_phase = 3;

      return new ByteBuffer[] { handshake, ByteBuffer.allocate( 5 ) };   //TODO convert to direct?
    }
    
    //System.out.println( "socks5 write phase 3..." );
    
    //reply has to be processed in two parts as it has variable length component at the end
    //socks5_handshake_phase == 3, part two
    socks5_handshake_phase = 4;
    return new ByteBuffer[] { null, ByteBuffer.allocate( socks5_address_length ) };       //TODO convert to direct?
  }
  
  
  
  private boolean parseSocks5Reply( ByteBuffer reply ) throws IOException {
    if( socks5_handshake_phase == 1 ) { // reply from hello
      //System.out.println( "socks5 read phase 1" );
      
      reply.get();  // version byte
      byte method = reply.get();

      if( method != 0 && method != 2 ) {
        throw new IOException( "SOCKS 5: no valid method [" + method + "]" );
      }

      // no auth -> go to request phase
      if( method == 0 ) {
        socks5_handshake_phase = 2;
      }
      
      return false;
    }
    
    if( socks5_handshake_phase == 2 ) {  // reply from auth
      //System.out.println( "socks5 read phase 2" );
      
      reply.get();  // version byte
      byte status = reply.get();

      if( status != 0 ) {
        throw new IOException( "SOCKS 5: authentication fails [status=" +status+ "]" );
      }

      return false;
    }
    
    
    if( socks5_handshake_phase == 3 ) {   // reply from request, first part
      //System.out.println( "socks5 read phase 3" );
      
      reply.get();  // version byte
      byte rep = reply.get();

      if( rep != 0 ) {
        String error_msgs[] = {
            "",
            "General SOCKS server failure",
            "connection not allowed by ruleset",
            "Network unreachable",
            "Host unreachable",
            "Connection refused",
            "TTL expired",
            "Command not supported",
            "Address type not supported" };
        String error_msg = rep < error_msgs.length ? error_msgs[ rep ] : "Unknown error";
        throw new IOException( "SOCKS request failure [" + error_msg + "/" + rep + "]" );
      }

      reply.get();  // reserved byte
      byte atype = reply.get();
      byte first_address_byte = reply.get();

      if( atype == 1 ) {
        socks5_address_length = 3; // already read one
      }
      else if( atype == 3 ) {
        socks5_address_length = first_address_byte;  // domain name, first byte gives length of remainder
      }
      else {
        socks5_address_length = 15; // already read one
      }

      socks5_address_length += 2;  // 2 bytes for port
      return false;
    }
    
    //System.out.println( "socks5 read phase 4..." );
    
    //socks5_handshake_phase 4
    //reply from request, last part
    return true;  //only done AFTER last part of request reply has been read from stream
  }
  
  

  
  public interface ProxyListener {
    /**
     * The proxied connection attempt succeeded.
     */
    public void connectSuccess() ;
    
    /**
     * The proxied connection attempt failed.
     * @param failure_msg failure reason
     */
    public void connectFailure( Throwable failure_msg );
  }
  
}