Basic SSHJ Usage

SshjBasic.java

package com.offbynull.rfm.ssh;

import java.io.IOException;
import net.schmizz.sshj.SSHClient;
import net.schmizz.sshj.connection.channel.direct.Session.Command;
import net.schmizz.sshj.userauth.keyprovider.KeyProvider;

public final class SshjBasic {
    
    public static void main(String[] args) throws Exception {
        try (SSHClient ssh = new SSHClient()) {
            // If you don't know the fingerprint of the host, use the following...
            //ssh.addHostKeyVerifier(new PromiscuousVerifier());  OR  ssh.addHostKeyVerifier((h, p, k) -> true);
            
            // If you do know the fingerprint of the host, add them using the following...
            //# ls -l /etc/ssh | grep ssh_host_.*_key
            //-rw------- 1 root root    668 Mar  6 18:05 ssh_host_dsa_key
            //-rw-r--r-- 1 root root    621 Mar  6 18:05 ssh_host_dsa_key.pub
            //-rw------- 1 root root    227 Mar  6 18:05 ssh_host_ecdsa_key
            //-rw-r--r-- 1 root root    193 Mar  6 18:05 ssh_host_ecdsa_key.pub
            //-rw------- 1 root root    432 Mar  6 18:05 ssh_host_ed25519_key
            //-rw-r--r-- 1 root root    113 Mar  6 18:05 ssh_host_ed25519_key.pub
            //-rw------- 1 root root   1675 Mar  6 18:05 ssh_host_rsa_key
            //-rw-r--r-- 1 root root    413 Mar  6 18:05 ssh_host_rsa_key.pub
            //# ssh-keygen -l -f /etc/ssh/ssh_host_rsa_key
            //2048 SHA256:ssyMcxeRiaGaPQ6DjGDck+gJw0C2Mo2Pt3FtIltdgM8 root@ubuntu-s-2vcpu-4gb-lon1-01 (RSA)
            ssh.addHostKeyVerifier("SHA256:ssyMcxeRiaGaPQ6DjGDck+gJw0C2Mo2Pt3FtIltdgM8");
            //# ssh-keygen -l -f /etc/ssh/ssh_host_dsa_key
            //1024 SHA256:FQUau86pV4LYI+Eu0JSHHurSyuWFdj6FpqMTPi27UBs root@ubuntu-s-2vcpu-4gb-lon1-01 (DSA)
            ssh.addHostKeyVerifier("SHA256:FQUau86pV4LYI+Eu0JSHHurSyuWFdj6FpqMTPi27UBs");
            //# ssh-keygen -l -f /etc/ssh/ssh_host_ecdsa_key
            //256 SHA256:z4TdK9nogKQfT+u5kfYiGgfnHlNRNbcplTmh0ASuXhw root@ubuntu-s-2vcpu-4gb-lon1-01 (ECDSA)
            ssh.addHostKeyVerifier("SHA256:z4TdK9nogKQfT+u5kfYiGgfnHlNRNbcplTmh0ASuXhw");
            //# ssh-keygen -l -f /etc/ssh/ssh_host_ed25519_key
            //256 SHA256:KjQYRkUQnb9cMnpjiTAtszmiglAu32/no2PGLg+WaaU root@ubuntu-s-2vcpu-4gb-lon1-01 (ED25519)
            ssh.addHostKeyVerifier("SHA256:KjQYRkUQnb9cMnpjiTAtszmiglAu32/no2PGLg+WaaU");


            // If you have a username and password...
            //ssh.connect("159.65.85.29", 22);
            //ssh.authPassword("root", "rootPassword");


            // If you have a SSH public/private key set up...
            //   on CLIENT, generate a key using "ssh-keygen -t rsa"
            //   copy CLIENT:~/.ssh/id_rsa.pub to SERVER:~/.ssh/authorized_keys
            //   copy CLIENT:~/.ssh/id_rsa.pub to privKey var below
            //   copy CLIENT:~/.ssh/id_rsa     to pubKey var (optional?)
            String privKey =
                    "-----BEGIN RSA PRIVATE KEY-----\n"
                    + "MIIEpAIBAAKCAQEAvng3ojjJG2l/NNiyrsN2c9x0oIbSEFGSVPltpWclZ+M12ZD7\n"
                    + "lC5ila0FhQozKKElSfoZyOIgyxq5wkHqIx41OU8ypDraL6rVt9Xuaoj7tGdrXrI0\n"
                    + "1Ip942wETidARDRkqgCbu3rvscwInI7bUVvQHIUTXKseMTT+ZwdHpncLdwueZbeY\n"
                    + "32FA90KfBj02xQvy4BPuDfR7uxo/16tm4r55JuvNhiytmi3okZ6ZXTopU42sZ+Yb\n"
                    + "8AFPm+s4muaVjg/dIAlXfUG5L4ouIhWuYJmS/BlZbz8kbt44Uubk6m84RiFbis0p\n"
                    + "q3AVmX2LF7v6Eb//JubtdDr0tzvIKsQAKd7gbwIDAQABAoIBAH8ivXfh0ZMjkw5S\n"
                    + "SsrOm6VwlMSF2XedC0D/EQoj1FsI1Wv5E4RwhcuEpzeLfGR1U++SKl3lWqBXoYCi\n"
                    + "AMgaJMqxK4tl4TeKH4fLG44vC1v64DdgWlU4cBk6g5ErMAGWu06ig1DcGVyjZWgj\n"
                    + "Dw+6aipvRWJIsimERv+8Yz4hHh0CEioUjQmporCNE8uuFRsWsiCQabAibqHJebF6\n"
                    + "x1Gh1y9gaGi2TtpzwE+CsL4wz8ST/MkMU2R4vZWEfcfYXSPombkQfhT3zMwt4zhq\n"
                    + "WXi+BXVVe82D/ZJnV3jmK9syqNJyR7QvrQW5rxWs/i3LYEwizH8ksI98NaUB/WMO\n"
                    + "mnfif6kCgYEA+xagr0hZ2+ziOscaK2XIwVOVmWpyMubOpCTmuCyun5JDy4RnGAFL\n"
                    + "tNGgXWlRhtrUpX1ZB8ZuWC6HU0lyJVhFJtvBQZBmHOMqudlga6OPUW7KBdIqX2Z2\n"
                    + "mhASSqYyIn0GTPhVJMeImaCY9Dh27fQYSLODSnPMGEAKiDj9UTxwxrUCgYEAwjIH\n"
                    + "l0poxwJoRzc+PYkJMTC3vPv38TjbbrCqJPZMqP7MU8QQJ4JKfOfPjm7UK4x/mSdx\n"
                    + "Bu6XC4uZKml0FNh4T4179TEWkOGJ8CjRDw7a+E4YidnQvo7f8CRm0xUY0c0XIphl\n"
                    + "EBy61XjcO8AZI3T0xnfgbbeiYd5lcTyDZ47rPRMCgYEAvFIyXoVDcGHxI+ilRhtn\n"
                    + "QSjxsUlXMbpPDmnm6ggJSQGo+4Ho2OZP4+S+BJGzZhPHHgAvwFch992d/ee+Ryg3\n"
                    + "ZXe5MPWewNfY+d+CI/leytLvjwIcacUt+0tGjNquC5P+H8i6A4XsfF0pmzKmcL59\n"
                    + "YDnTpQnI7/9IZvdnd4B/jWkCgYBaf1AUTAPKAjAwR+lEafETsF1fv5hLHLD9w2x2\n"
                    + "7yTIeH0l6C+TCd/Gl4ydFr7fUIlCCSReE5/mLHcDUcNb14kxoYCLwgV/HOvYNF1A\n"
                    + "hC69Gj/LNetWcmSfl4cnhSRc2ROX9qbaPFlBFCKl4Z6VbHKJbuHyn2oX67kgbQ/b\n"
                    + "mbm8awKBgQDEPCH80SgMyqao3pgavH/MZBJbngWFtFYwXsZdHdVfaONUqxij4mII\n"
                    + "sqnE6nqXcNReCOf/fExLM/ZIBZPXU+YXFpjn6GsBT01xerAsVlln/D1UFU1BOdSB\n"
                    + "qbPrtQTqoGqkwvpLfTmywteTFrMuLNM8VoaEFsinq21P2RYcRpEf5g==\n"
                    + "-----END RSA PRIVATE KEY-----";
            String pubKey = "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC+eDeiOMkbaX802LKuw3Zz3HSghtIQUZJU+W2lZyVn4zXZkPuULmKVrQWFCjMooSVJ+hnI4iDLGrnCQeojHjU5TzKkOtovqtW31e5qiPu0Z2tesjTUin3jbAROJ0BENGSqAJu7eu+xzAicjttRW9AchRNcqx4xNP5nB0emdwt3C55lt5jfYUD3Qp8GPTbFC/LgE+4N9Hu7Gj/Xq2bivnkm682GLK2aLeiRnpldOilTjaxn5hvwAU+b6zia5pWOD90gCVd9Qbkvii4iFa5gmZL8GVlvPyRu3jhS5uTqbzhGIVuKzSmrcBWZfYsXu/oRv/8m5u10OvS3O8gqxAAp3uBv User@DESKTOP-G7T6KOV";
            KeyProvider keyProvider = ssh.loadKeys(privKey, pubKey, null); // implement a PasswordFinder instance and pass in as 3rd arg if your pub/priv key is secured by a password
            ssh.connect("159.65.85.29", 22);
            ssh.authPublickey("root", keyProvider);
            
            
            
            // Execute command
            Command cmd = ssh.startSession().exec("echo hi");
            cmd.join();
            System.out.println(cmd.getExitStatus());
        }
    }
}