Java linux SSH 免密（公钥）连接并多服务器进行SCP

冷不防 2022-09-11 01:11 219阅读 0赞

参考博客地址：

[Java 实现 SCP 携带密码拷贝文件 - 龙凌云端 - 博客园][Java _ SCP _ - _ -]、

[java免密连接SSH\_寂寞的博客-CSDN博客][java_SSH_-CSDN]

背景：项目中需要多台服务器之间进行文件传输，起初，使用的是密码认证的方式，但是服务器的密码会每三个月强制修改一次，这会影响到文件的正常传输，所以后面考虑使用ssh 公钥的认证方式

1、linux 不同服务器scp免密远程传输文件实例 ssh 免密登录 配置

本步骤参考本人博客：[linux 不同服务器scp免密远程传输文件实例 ssh 免密登录\_chen\_lay的博客-CSDN博客][linux _scp_ ssh _chen_lay_-CSDN]

2、java 实现 ssh scp 免密（公钥）多服务器间的文件传输

a、maven依赖

<dependency>
        <groupId>org.apache.sshd</groupId>
        <artifactId>sshd-common</artifactId>
        <version>2.7.0</version>
    </dependency>
    
    
    <dependency>
        <groupId>org.apache.sshd</groupId>
        <artifactId>sshd-core</artifactId>
        <version>2.7.0</version>
    </dependency>
    
    
    <dependency>
        <groupId>org.apache.sshd</groupId>
        <artifactId>sshd-scp</artifactId>
        <version>2.7.0</version>
    </dependency>

b、具体的工具类

import org.apache.sshd.client.SshClient;
    import org.apache.sshd.client.keyverifier.DefaultKnownHostsServerKeyVerifier;
    import org.apache.sshd.client.keyverifier.KnownHostsServerKeyVerifier;
    import org.apache.sshd.client.keyverifier.ServerKeyVerifier;
    import org.apache.sshd.client.session.ClientSession;
    import org.apache.sshd.scp.client.ScpClient;
    import org.apache.sshd.scp.client.ScpClientCreator;
    
    import java.io.*;
    import java.net.SocketAddress;
    import java.nio.file.Files;
    import java.nio.file.InvalidPathException;
    import java.security.KeyPair;
    import java.security.KeyPairGenerator;
    import java.security.NoSuchAlgorithmException;
    import java.security.PublicKey;
    
    public class ScpClientUtil {
        private static String host = "10.186.83.100";
        private static String username = "username";
        private static String password = "password";
        private static Integer port = 22;
    
        private static String local = "/home/mg/data/customer_contract/";
        private static String remote = "/home/mg/data/customer_contract/";
        private static String idRsaPath = "/home/mg/.ssh/id_ras";
    
        public static void scpFile(String local, String remote, boolean strictHostKey) throws Exception {
            long startTime = System.currentTimeMillis();
    
            // 创建 SSH客户端
            SshClient client = SshClient.setUpDefaultClient();
            KnownHostsServerKeyVerifier verifier = new DefaultKnownHostsServerKeyVerifier(new ServerKeyVerifier() {
                @Override
                public boolean verifyServerKey(ClientSession clientSession, SocketAddress remoteAddress,
                                               PublicKey serverKey) {
                    return !strictHostKey;
                }
            }, true);
    
            client.setServerKeyVerifier(verifier);
            // 启动 SSH客户端
            client.start();
            // 通过主机IP、端口和用户名，连接主机，获取Session
            ClientSession session = client.connect(username, host, port).verify().getSession();
            // 给Session添加密码
            // session.addPasswordIdentity(password);
            // publicKey方式认证
            session.addPublicKeyIdentity(getKeyPairFromString(readPemFile(new File(idRsaPath))));
            // 校验用户名和密码的有效性
            boolean isSuccess = session.auth().verify(10000L).isSuccess();
    
            // 认证成功
            if (isSuccess) {
                long middleTime = System.currentTimeMillis();
                System.out.println("Connect host cost time: " + (middleTime - startTime) / 1000.0 + "s.");
    
                ScpClientCreator creator = ScpClientCreator.instance();
                // 创建 SCP 客户端
                ScpClient scpClient = creator.createScpClient(session);
    
                System.out.println("Scp beginning.");
                // ScpClient.Option.Recursive：递归copy，可以将子文件夹和子文件遍历copy
                scpClient.upload(local, remote);
                 scpClient.download(remote, local);
                System.out.println("Scp finished.");
    
                // 释放 SCP客户端
                if (scpClient != null) {
                    scpClient = null;
                }
    
                // 关闭 Session
                if (session != null && session.isOpen()) {
                    session.close();
                }
    
                // 关闭 SSH客户端
                if (client != null && client.isOpen()) {
                    client.stop();
                    client.close();
                }
            }
    
            long endTime = System.currentTimeMillis();
            System.out.println("Total Cost time: " + (endTime - startTime) / 1000.0 + "s.");
        }
    
        /**
         * 读取文件内容
         */
        public static String readPemFile(File f) throws IOException {
            try (InputStream is = Files.newInputStream(f.toPath());
                 DataInputStream dis = new DataInputStream(is)) {
                byte[] bytes = new byte[(int) f.length()];
                dis.readFully(bytes);
                return new String(bytes);
            } catch (InvalidPathException e) {
                throw new IOException(e);
            }
        }
    
        /**
         * 获取密钥对
         */
        static KeyPair getKeyPairFromString(String pk) throws IOException, NoSuchAlgorithmException {
            final KeyPairGenerator rsa = KeyPairGenerator.getInstance("RSA");
            final KeyPair keyPair = rsa.generateKeyPair();
            final ByteArrayOutputStream stream = new ByteArrayOutputStream();
            stream.write(pk.getBytes());
            final ObjectOutputStream o = new ObjectOutputStream(stream);
            o.writeObject(keyPair);
            return keyPair;
        }
    
        public static void main(String[] args) throws Exception {
            scpFile(local, remote, false);
        }
    }

c、执行结果：

>     Connect host cost time: 3.533s.
>     Scp beginning.
>     Scp finished.
>     Total Cost time: 4.545s.

[Java _ SCP _ - _ -]: https://www.cnblogs.com/miracle-luna/p/15037782.html
[java_SSH_-CSDN]: https://blog.csdn.net/jimo_lonely/article/details/107774230
[linux _scp_ ssh _chen_lay_-CSDN]: https://blog.csdn.net/chen_lay/article/details/120138909?spm=1001.2014.3001.5501