[sshd] issue sshd-core-1.0.0 sshd command while redirecting

[Alon Bar-Lev]

Hi,

What is the status of 1.0.0? I see vote completed and published to central
but I do not see it within the site.

While trying to test what in central, I found the following issue, I am
unsure how to find root cause or if it is formal release.

Please build the attached primitive sshd, it is used only for testing.

Try to execute:

$ echo xxxx | ssh -p @PORT@ root@localhost "cat > /none/exist/path/file"

You should get the following exception in 9:10 attempts:

Exception in thread "sshd-shell[855da06]-thread-1"
java.lang.NullPointerException
        at
org.apache.sshd.server.shell.ProcessShellFactory$ProcessShell.exitValue(ProcessShellFactory.java:170)
        at
org.apache.sshd.server.shell.InvertedShellWrapper.pumpStreams(InvertedShellWrapper.java:165)
        at
org.apache.sshd.server.shell.InvertedShellWrapper$1.run(InvertedShellWrapper.java:125)
        at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)

I cannot understand how process can be null in this context.

Regards,
Alon Bar-Lev.

import java.io.IOException;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.util.LinkedList;
import java.util.List;

import org.apache.sshd.common.keyprovider.AbstractKeyPairProvider;
import org.apache.sshd.server.Command;
import org.apache.sshd.server.CommandFactory;
import org.apache.sshd.server.SshServer;
import org.apache.sshd.server.auth.password.PasswordAuthenticator;
import org.apache.sshd.server.auth.pubkey.PublickeyAuthenticator;
import org.apache.sshd.server.session.ServerSession;
import org.apache.sshd.server.shell.ProcessShellFactory;

public class SSHD {

    static class MyPasswordAuthenticator implements PasswordAuthenticator {
        String _user;
        String _password;

        public MyPasswordAuthenticator(String user, String password) {
            _user = user;
            _password = password;
        }

        @Override
        public boolean authenticate(String user, String password, ServerSession session) {
            return _user.equals(user) && _password.equals(password);
        }
    }

    static class MyPublickeyAuthenticator implements PublickeyAuthenticator {
        String _user;
        PublicKey _key;

        public MyPublickeyAuthenticator(String user, PublicKey key) {
            _user = user;
            _key = key;
        }

        @Override
        public boolean authenticate(String user, PublicKey key, ServerSession session) {
            return _user.equals(user) && _key.equals(key);
        }
    }

    static class MyKeyPairProvider extends AbstractKeyPairProvider {
        KeyPair _keyPair;

        public MyKeyPairProvider(KeyPair keyPair) {
            _keyPair = keyPair;
        }

        @Override
        public Iterable<KeyPair> loadKeys() {
            List<KeyPair> ret = new LinkedList<>();
            ret.add(_keyPair);
            return ret;
        }
    }

    KeyPair _keyPair;
    String _user;
    String _userPassword;
    PublicKey _userKey;
    SshServer _sshd;

    public SSHD() {
        try {
            _keyPair = KeyPairGenerator.getInstance("RSA").generateKeyPair();
        }
        catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
        _sshd = SshServer.setUpDefaultServer();
        _sshd.setKeyPairProvider(new MyKeyPairProvider(_keyPair));
        _sshd.setShellFactory(
            new ProcessShellFactory(
                new String[] {
                    "/bin/sh",
                    "-i"
                }
            )
        );
        _sshd.setCommandFactory(
            new CommandFactory() {
                @Override
                public Command createCommand(String command) {
                    return new ProcessShellFactory(
                        new String[] {
                            "/bin/sh",
                            "-c",
                            command
                        }
                    ).create();
                }
            }
        );
    }

    public int getPort() {
        return _sshd.getPort();
    }

    public PublicKey getKey() {
        return _keyPair.getPublic();
    }

    public void setUser(String user, String password, PublicKey key) {
        _sshd.setPasswordAuthenticator(new MyPasswordAuthenticator(user, password));
        _sshd.setPublickeyAuthenticator(new MyPublickeyAuthenticator(user, key));
    }

    public void start() throws IOException {
        _sshd.start();
    }

    public void stop() {
        while (_sshd != null) {
            try {
                _sshd.stop(true);
                _sshd = null;
            }
            catch (IOException e) {}
        }
    }


    public static void main(String [] args) throws Exception {
        KeyPair keyPair = KeyPairGenerator.getInstance("RSA").generateKeyPair();

        SSHD sshd = new SSHD();
        sshd.setUser("root", "password", keyPair.getPublic());
        sshd.start();
        System.out.println("Port: " + sshd.getPort());
        Thread.currentThread().sleep(60000);
    }
}