socks.server.Ident Maven / Gradle / Ivy
/**
* Copyright 2003-2016 SSHTOOLS Limited. All Rights Reserved.
*
* For product documentation visit https://www.sshtools.com/
*
* This file is part of J2SSH Maverick.
*
* J2SSH Maverick is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* J2SSH Maverick 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 J2SSH Maverick. If not, see
To use it:
Socket s = ss.accept();
Ident id = new Ident(s);
if(id.successful) goUseUser(id.userName);
else handleIdentError(id.errorCode,id.errorMessage)
*/
public class Ident{
/** Error Message can be null.*/
public String errorMessage;
/** Host type as returned by daemon, can be null, if error happened*/
public String hostType;
/** User name as returned by the identd daemon, or null, if it failed*/
public String userName;
/** If this is true then userName and hostType contain valid values.
Else errorCode contain the error code, and errorMessage contains
the corresponding message.
*/
public boolean successful;
/** Error code*/
public int errorCode;
/** Identd on port 113 can't be contacted*/
public static final int ERR_NO_CONNECT = 1;
/** Connection timed out*/
public static final int ERR_TIMEOUT = 2;
/** Identd daemon responded with ERROR, in this case errorMessage
contains the string explanation, as send by the daemon.
*/
public static final int ERR_PROTOCOL = 3;
/**
When parsing server response protocol error happened.
*/
public static final int ERR_PROTOCOL_INCORRECT = 4;
/** Maximum amount of time we should wait before dropping the
connection to identd server.Setting it to 0 implies infinit
timeout.
*/
public static final int connectionTimeout = 10000;
/**
Constructor tries to connect to Identd daemon on the host of the
given socket, and retrieve user name of the owner of given socket
connection on remote machine. After constructor returns public
fields are initialised to whatever the server returned.
If user name was successfully retrieved successful is set to true,
and userName and hostType are set to whatever server returned. If
however for some reason user name was not obtained, successful is set
to false and errorCode contains the code explaining the reason of
failure, and errorMessage contains human readable explanation.
Constructor may block, for a while.
@param s Socket whose ownership on remote end should be obtained.
*/
public Ident(Socket s ){
Socket sock = null;
successful = false; //We are pessimistic
try{
sock = new Socket(s.getInetAddress(),113);
sock.setSoTimeout(connectionTimeout);
byte[] request = (""+s.getPort()+" , "+
s.getLocalPort()+"\r\n").getBytes();
sock.getOutputStream().write(request);
BufferedReader in = new BufferedReader(
new InputStreamReader(sock.getInputStream()));
parseResponse(in.readLine());
}catch(InterruptedIOException iioe){
errorCode = ERR_TIMEOUT;
errorMessage = "Connection to identd timed out.";
}catch(ConnectException ce){
errorCode = ERR_NO_CONNECT;
errorMessage = "Connection to identd server failed.";
}catch(IOException ioe){
errorCode = ERR_NO_CONNECT;
errorMessage = ""+ioe;
}finally{
try{ if(sock!=null) sock.close();}catch(IOException ioe){};
}
}
private void parseResponse(String response){
if(response == null){
errorCode = ERR_PROTOCOL_INCORRECT;
errorMessage = "Identd server closed connection.";
return;
}
StringTokenizer st = new StringTokenizer(response,":");
if(st.countTokens() < 3){
errorCode = ERR_PROTOCOL_INCORRECT;
errorMessage = "Can't parse server response.";
return;
}
st.nextToken(); //Discard first token, it's basically what we have send
String command = st.nextToken().trim().toUpperCase();
if(command.equals("USERID") && st.countTokens() >= 2){
successful = true;
hostType = st.nextToken().trim();
userName = st.nextToken("").substring(1);//Get all that is left
}else if(command.equals("ERROR")){
errorCode = ERR_PROTOCOL;
errorMessage = st.nextToken();
}else{
errorCode = ERR_PROTOCOL_INCORRECT;
System.out.println("Opa!");
errorMessage = "Can't parse server response.";
}
}
///////////////////////////////////////////////
//USED for Testing
/*
public static void main(String[] args) throws IOException{
Socket s = null;
s = new Socket("gp101-16", 1391);
Ident id = new Ident(s);
if(id.successful){
System.out.println("User: "+id.userName);
System.out.println("HostType: "+id.hostType);
}else{
System.out.println("ErrorCode: "+id.errorCode);
System.out.println("ErrorMessage: "+id.errorMessage);
}
if(s!= null) s.close();
}
//*/
}