java - example - Envío de comandos al servidor a través del canal de shell JSch

leer archivo sftp java

Question

No puedo entender cómo puedo enviar comandos a través del canal de shell JSch.

Hago esto, pero no funciona:

JSch shell = new JSch();
String command = "cd home/s/src";
Session session = shell.getSession(username, host, port);
MyUserInfo ui = new MyUserInfo();
ui.setPassword(password);
session.setUserInfo(ui);
session.connect();
channel = session.openChannel("shell");
fromServer = new BufferedReader(new InputStreamReader(channel.getInputStream()));
toServer = channel.getOutputStream();
channel.connect();
toServer.write((command + "/r/n").getBytes());
toServer.flush();

y luego leo una entrada como esta:

StringBuilder builder = new StringBuilder();
int count = 0;
String line = "";
while(line != null) {
line = fromServer.readLine();
builder.append(line).append("/n");
if (line.endsWith(".") || line.endsWith(">")){
break;
}
}
String result = builder.toString();
ConsoleOut.println(result);

Answer 1

Con las transmisiones de entrada y salida por tuberías parece interesante:

JSch jsch = new JSch();
jsch.addIdentity("/home/audrius/.ssh/blablabla", "blablablabla");
String user = "audrius";
String host = "ultrastudio.org";
Session session = jsch.getSession(user, host, 439);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
Channel channel = session.openChannel("shell");
PipedInputStream pip = new PipedInputStream(40);
channel.setInputStream(pip);
PipedOutputStream pop = new PipedOutputStream(pip);
PrintStream print = new PrintStream(pop);
channel.setOutputStream(System.out);
print.println("ls");

Answer 2

Lo siguiente fue un código escrito rápidamente para mi tarea. No es un programa bien hecho. Pero cumple su propósito.

1. Se conecta vía SSH (usando Jsch) a un servidor (usando un archivo de clave privada - mykey.pem)
2. Crea un script de shell (para montar un volumen y mkfs)
3. Se ejecuta en la máquina remota
4. Mientras tanto, puede ver la salida en su stdout

El código sigue:

public class connectSSH {
public void connect(String dnsName, String privKey) throws IOException {
JSch jSch = new JSch();
try {
//Authenticate through Private Key File
jSch.addIdentity(privKey);
//Give the user and dnsName
Session session = jSch.getSession("root", dnsName, 22);
//Required if not a trusted host
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
System.out.println("Connecting SSH to " + dnsName + " - Please wait for few minutes... ");
session.connect();
//Open a shell
Channel channel=session.openChannel("shell");
channel.setOutputStream(System.out);
//Create a Shell Script
File shellScript = createShellScript();
//Convert the shell script to byte stream
FileInputStream fin = new FileInputStream(shellScript);
byte fileContent[] = new byte[(int)shellScript.length()];
fin.read(fileContent);
InputStream in = new ByteArrayInputStream(fileContent);
//Set the shell script to the channel as input stream
channel.setInputStream(in);
//Connect and have fun!
channel.connect();
} catch (JSchException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public File createShellScript() {
String filename = "shellscript.sh";
File fstream = new File(filename);
try{
// Create file
PrintStream out = new PrintStream(new FileOutputStream(fstream));
out.println("#!/bin/bash");
out.println("echo /"hi/" > /tmp/test.info");
out.println("echo /"n/" > /tmp/fdisk.in");
out.println("echo /"p/" >> /tmp/fdisk.in");
out.println("echo /"1/" >> /tmp/fdisk.in");
out.println("echo >> /tmp/fdisk.in");
out.println("echo >> /tmp/fdisk.in");
out.println("echo /"w/" >> /tmp/fdisk.in");
out.println("/sbin/fdisk /dev/sdf < /tmp/fdisk.in");
out.println("mkfs.ext3 /dev/sdf1");
out.println("mkdir /usr/myebs");
out.println("mount /dev/sdf1 /usr/myebs");
out.println("partprobe /dev/sdf1");
out.println("echo /"Success/"");
//Close the output stream
out.close();
}catch (Exception e){//Catch exception if any
System.err.println("Error: " + e.getMessage());
}
return fstream;
}
public static void main(String[] args) {
connectSSH ssh = new connectSSH();
String privKey = "/Users/neo/Desktop/mykey.pem";
try {
ssh.connect("yourexampleserver.com", privKey);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

Answer 3

Me doy cuenta de que este es un hilo viejo, pero hoy he tenido problemas similares. Esta es mi solución.

public class ChannelConsole {
// ================================================
// static fields
// ================================================
// ================================================
// instance fields
// ================================================
private Session session;
// ================================================
// constructors
// ================================================
public ChannelConsole(Session session) {
this.session = session;
}
// ================================================
// getters and setters
// ================================================
// ================================================
// public methods
// ================================================
public String execute(String command) throws JSchException {
command = command.trim() + "/n";
ChannelExec channel = (ChannelExec) this.session.openChannel("exec");
channel.setCommand(command);
ByteArrayOutputStream responseStream = new ByteArrayOutputStream();
channel.setOutputStream(responseStream);
channel.connect();
try {
awaitChannelClosure(channel);
} catch (InterruptedException e) {
// no one cares
}
String result = responseStream.toString();
closeQuietly(responseStream);
return result;
}
// ================================================
// private methods
// ================================================
private void awaitChannelClosure(ChannelExec channel) throws InterruptedException {
while (channel.isConnected()) {
Thread.sleep(100);
}
}
private static void closeQuietly(Closeable closeable) {
if (closeable == null) {
return;
}
try {
closeable.close();
} catch (IOException ignored) {
ignored.printStackTrace();
}
}
}

Usando esta clase puedes hacer algo como: shell = new ChannelConsole(this.session); String result = shell.execute("quota -v; echo; echo /"Disk storage information:/"; df -hk") shell = new ChannelConsole(this.session); String result = shell.execute("quota -v; echo; echo /"Disk storage information:/"; df -hk")

Answer 4

Prueba esto:

JSch jsch = new JSch();
try
{
Session session = jsch.getSession("root", "192.168.0.1", 22);
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
session.connect();
String command = "lsof -i :80";
Channel channel = session.openChannel("exec");
((ChannelExec) channel).setCommand(command);
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();
}
catch (Exception e)
{
System.out.println(e.getMessage());
}

Answer 5

Si se cuelga en readLine() eso significa que su "while" nunca termina (puede ser improbable considerando su código), o que readLine() está esperando su fuente, es decir, que IOstream bloquea la causa de la IOstream available()!=true .

No puedo solucionar el problema de tu código sin ver tu información de depuración. Pero como consejo, ¿has probado PipedIntputStream ? La idea es conectar la entrada de tu consola a "tu" salida para que puedas "escribirla". Para implementar esto, debe inicializar la entrada / salida.

InputStream in = new PipedInputStream();
PipedOutputStream pin = new PipedOutputStream((PipedInputStream) in);
/**...*/
channel.setInputStream(in);
channel.connect();
/** ...*/
pin.write(myScript.getBytes());

Lo mismo ocurre con su pregunta, cómo leer la salida de la consola.

PipedInputStream pout = new PipedInputStream((PipedOutputStream) out);
/**
* ...
*/
BufferedReader consoleOutput = new BufferedReader(new InputStreamReader(pout));
consoleOutput.readLine();

Y de nuevo, si no está seguro de cuántas líneas leer y, por lo tanto, desea usar "while", asegúrese de hacer algo dentro mientras evita 1) busy-waiting 2) ending-condition. Ejemplo:

while(!end)
{
consoleOutput.mark(32);
if (consoleOutput.read()==0x03) end = true;//End of Text
else
{
consoleOutput.reset();
consoleOutput.readLine();
end = false;
}
}

Answer 6

Uso:

String remoteCommandOutput = exec("ssh://user:pass@host/work/dir/path", "ls -t | head -n1");
String remoteShellOutput = shell("ssh://user:pass@host/work/dir/path", "ls")
shell("ssh://user:pass@host/work/dir/path", "ls", System.out)
shell("ssh://user:pass@host", System.in, System.out);

Implementation

Answer 7

prueba este código:

 JSch jsch=new JSch();
System.out.println("Getting session");
Session session=jsch.getSession("root","10.0.0.0",22);
System.out.println("session is ::::"+session.getHost());
// username and password will be given via UserInfo interface.
UserInfo ui = new MyUserInfo("Lab@123", null);
//UserInfo ui = new MyUserInfo(password, null);
session.setUserInfo(ui);
session.setPassword("Lab@123");
Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
session.connect(40000);
Channel channel=session.openChannel("exec");
((ChannelExec)channel).setCommand("ls");
channel.connect();
channel.run();
// get I/O streams for remote scp
OutputStream out=channel.getOutputStream();
InputStream in=channel.getInputStream();
String output="";
while (channel.isClosed()!=true) {
try {
output+=streamToString(in);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
System.out.println("Output is :::"+output);
channel.disconnect();
session.disconnect();
}
public static String streamToString(InputStream input)throws Exception
{ String output = ""; while(input.available()>0) { output += ((char)(input.read())); } return output; }
public static OutputStream stringToStream(String charset) throws IOException{
byte[] bytes = charset.getBytes();
/*ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
InputStreamReader isr = new InputStreamReader(bais);*/
InputStream is = null;
OutputStream os = null;
try {
is = new ByteArrayInputStream(charset.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//byte[] buf = new byte[1024];
int numRead;
while ( (numRead = is.read(bytes) ) >= 0) {
os.write(bytes, 0, numRead);
}
return os;

Answer 8

prueba esto

Channel channel=session.openChannel("shell");
OutputStream ops = channel.getOutputStream();
PrintStream ps = new PrintStream(ops, true);
channel.connect();
ps.println("mkdir folder");
ps.println("dir");
//give commands to be executed inside println.and can have any no of commands sent.
ps.close();
InputStream in=channel.getInputStream();
byte[] bt=new byte[1024];
while(true)
{
while(in.available()>0)
{
int i=in.read(bt, 0, 1024);
if(i<0)
break;
String str=new String(bt, 0, i);
//displays the output of the command executed.
System.out.print(str);
}
if(channel.isClosed())
{
break;
}
Thread.sleep(1000);
channel.disconnect();
session.disconnect();
}

Answer 9

private void executeRemoteCommandAsSudo(String sudoAs, String password,
String command, int delayInSeconds)
{
logger.info("executeRemoteCommandAsSudo started....");
logger.info("sudoAs=" + sudoAs);
logger.info("command=" + command);
logger.info("delayInSeconds=" + delayInSeconds);
Session session = null;
Channel channel = null;
try {
session = getSession();
channel = session.openChannel("exec");
String sudoCommand = "sudo su - " + sudoAs;
((ChannelExec) channel).setCommand(sudoCommand);
((ChannelExec) channel).setPty(true);
channel.connect();
InputStream inputStream = channel.getInputStream();
OutputStream out = channel.getOutputStream();
((ChannelExec) channel).setErrStream(System.err);
out.write((password + "/n").getBytes());
out.flush();
Thread.sleep(1000);
out.write((command + "/n").getBytes());
out.flush();
Thread.sleep(1000 * delayInSeconds);
out.write(("logout" + "/n").getBytes());
out.flush();
Thread.sleep(1000);
logInfo(channel, inputStream);
out.write(("exit" + "/n").getBytes());
out.flush();
out.close();
Thread.sleep(1000);
} catch (Exception ex) {
logger.error(ex.getMessage());
} finally {
session.disconnect();
channel.disconnect();
}
logger.info("executeRemoteCommandAsSudo completed....");
}
private void logInfo(Channel channel, InputStream in)
{
try {
byte[] tmp = new byte[1024];
while (true) {
while (in.available() > 0) {
int i = in.read(tmp, 0, 1024);
if (i < 0)
break;
logger.info(new String(tmp, 0, i));
}
if (channel.isClosed()) {
logger.info("exit-status: " + channel.getExitStatus());
break;
}
}
} catch (Exception ex) {
logger.error(ex);
}
}
private Session getSession() throws JSchException
{
JSch jsch = new JSch();
logger.info("ftpUser=" + ftpUser);
logger.info("ftpHost=" + ftpHost);
Session session = jsch.getSession(ftpUser, ftpHost, 22);
session.setPassword(ftpPassword);
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
session.connect();
return session;
}