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Simple Socks over SSH tunnel in Andorid Java

I need to setup a socks proxy (tunnel) over ssh in android with java (android studio). I searched a lot but I couldn't find any solutions. This is my code:
int assigned_port;
int local_port=8588;
int remote_port=22;
String remote_host = "server";
String login = "root";
String password = "password";
try {
JSch jsch = new JSch();
// Create SSH session. Port 22 is your SSH port which
// is open in your firewall setup.
Session session = jsch.getSession(login, remote_host, 22);
session.setPassword(password);
// Additional SSH options. See your ssh_config manual for
// more options. Set options according to your requirements.
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
// config.put("Compression", "yes");
config.put("ConnectionAttempts","2");
session.setConfig(config);
// Connect
session.connect();
// Create the tunnel through port forwarding.
// This is basically instructing jsch session to send
// data received from local_port in the local machine to
// remote_port of the remote_host
// assigned_port is the port assigned by jsch for use,
// it may not always be the same as
// local_port.
assigned_port = session.setPortForwardingL(local_port,
remote_host, remote_port);
} catch (JSchException e) {
System.out.println("JSch:" + e.getMessage());
return;
}
if (assigned_port == 0) {
System.out.println("Port forwarding failed!");
return;
}
There is no error but it didn't work. I need a simple code of socks tunneling.

How to echo a string to SSH using JAVA

I am trying to execute a remote query over SSH using pubic key/private key based authentication. Following command works fine and gives me the required output as a string on a bash shell after sharing the public keys between local host and the remote server.
echo 123456 12#13:14 ABCD abc1234 | ssh -T user#abc.xyz.com
How do I achieve the same with JAVA using JSCH or SSHJ or any other similar library
This is what I have tried so far using SSHJ but it did not work for me (Connection was successful but no results)
public static void main(String... args)throws IOException {
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts();
ssh.connect("abc.xyz.com");
try {
ssh.authPublickey("user");
final Session session = ssh.startSession();
try {
final Command cmd = session.exec("123456 12#13:14 ABCD abc1234");
System.out.println(IOUtils.readFully(cmd.getInputStream()).toString());
cmd.join(5, TimeUnit.SECONDS);
System.out.println("\n** exit status: " + cmd.getExitStatus());
} finally {
session.close();
}
} finally {
ssh.disconnect();
ssh.close();
}
}

Below code uses JSCH Library and is working on my end :-
JSch jsch = new JSch();
String path = "PATH TO PRIVATE KEY";
jsch.addIdentity(path);
jsch.setConfig("StrictHostKeyChecking", "no");
Session session = jsch.getSession(userName, ipToConnect, portToConnect);
session.connect();
Channel channel = session.openChannel("exec");
((ChannelExec)channel).setCommand("COMMAND TO FIRE");
channel.setInputStream(null);
((ChannelExec)channel).setErrStream(System.err);
InputStream in = channel.getInputStream();
channel.connect();
//Read Response Here
channel.disconnect();
session.disconnect();
Note : You can use password based authentication also instead of key bases with JSCH

How to use a command-line *nix command that needs an interactive terminal over JSch SSH session in Java?

I'm trying to create code in java that sends SMS using GSM modem through minicom package that I tested successfully in Linux.
Right know I'm using JSch library to SSH and use minicom. I've successfully tested this code with normal Linux commands.
import java.io.InputStream;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
public class SSHCommandExecutor {
/**
* #param args
*/
public static void main(String[] args) {
String host="localhost";
String user="root";
String password="XXXXX";
String command1="minicom";
try{
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
JSch jsch = new JSch();
Session session=jsch.getSession(user, host, 22);
session.setPassword(password);
session.setConfig(config);
session.connect();
System.out.println("Connected");
Channel channel=session.openChannel("exec");
((ChannelExec)channel).setCommand(command1);
channel.setInputStream(null);
((ChannelExec)channel).setErrStream(System.err);
InputStream in=channel.getInputStream();
channel.connect();
byte[] tmp=new byte[1024];
while(true){
while(in.available()>0){
int i=in.read(tmp, 0, 1024);
if(i<0)break;
System.out.print(new String(tmp, 0, i));
}
if(channel.isClosed()){
System.out.println("exit-status: "+channel.getExitStatus());
break;
}
try{Thread.sleep(1000);}catch(Exception ee){}
}
channel.disconnect();
session.disconnect();
System.out.println("DONE");
}catch(Exception e){
e.printStackTrace();
}
}
}
But the problem is that I can't send commands to minicom it will output this:
No cursor motion capability (cm)
I believe it need terminal environment and I don't want to use terminal emulator in Java. I just want to send command to minicom through Java code.
Is there any way I could do this?
PS: I've tried other possibilities to solve this using smslib but it couldn't work properly in Linux cause of the rxtx and other solutions. Right now only minicom works properly.

If the problem is indeed that the command does not start on a non-interactive terminal, yet it does not really need any interactivity, you can simply make the "exec" channel "interactive" by using .setPty(true) call.
channel.setPty(true);
channel.connect();

JSchException: Auth fail and fingerprint

I'm trying to connect to my SFTP server from a Java script.
I'm using JSch lib for my purpose. Username, password and hostname are correct but I obtain an: Auth fail error.
I've also tried to add the following lines before session.connect(), but the problem still remains.
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
What do I have to put inside knownhosts.txt? The fingerprint of my server key?
public static void upload(ArrayList<File> a) {
try{
JSch jsch = new JSch();
jsch.setKnownHosts("knownhosts.txt");
Session session = jsch.getSession("username", "hostname", 22);
session.setPassword("mypassword");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp channelSftp = (ChannelSftp) channel;
channelSftp.cd("/var/www/");
for(File object: a){
channelSftp.put(new FileInputStream(object), object.getName(), channelSftp.OVERWRITE);
}
channelSftp.exit();
session.disconnect();
} catch (Exception ex) {
ex.printStackTrace();
}
}
Do you have some advices? Thanks in advance!

Does your network/SMTP server support IP6? If your client has IP6 support, later versions of Java default to IP6, but many SMTP servers are configured on IP4. See this article here for Sending email using JSP for directions on configuring your JVM to force IP4. This needs to be set on the JVM as it is instantiated.

Can we use JSch for SSH key-based communication?

I am using JSch for sftp communication, now i want to use facilitate the key-based authentication, key is loaded on client and server machine once by my network team and all later communication would be only user based for which we have loaded the key.
sftp -oPort=10022 jmark#192.18.0.246
as tjill#192.18.0.135
like this command work fine and connect to the sftp, how i can achieve this functionality programmatically.
if it is not possible using JSch, please suggest some other library. I came across Apache SSHD.

It is possible. Have a look at JSch.addIdentity(...)
This allows you to use key either as byte array or to read it from file.
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
public class UserAuthPubKey {
public static void main(String[] arg) {
try {
JSch jsch = new JSch();
String user = "tjill";
String host = "192.18.0.246";
int port = 10022;
String privateKey = ".ssh/id_rsa";
jsch.addIdentity(privateKey);
System.out.println("identity added ");
Session session = jsch.getSession(user, host, port);
System.out.println("session created.");
// disabling StrictHostKeyChecking may help to make connection but makes it insecure
// see http://stackoverflow.com/questions/30178936/jsch-sftp-security-with-session-setconfigstricthostkeychecking-no
//
// java.util.Properties config = new java.util.Properties();
// config.put("StrictHostKeyChecking", "no");
// session.setConfig(config);
session.connect();
System.out.println("session connected.....");
Channel channel = session.openChannel("sftp");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect();
System.out.println("shell channel connected....");
ChannelSftp c = (ChannelSftp) channel;
String fileName = "test.txt";
c.put(fileName, "./in/");
c.exit();
System.out.println("done");
} catch (Exception e) {
System.err.println(e);
}
}
}