我的 JSch 会话不执行命令

Question

我正在尝试编写一个 Java 代码，可以通过 ssh 连接到 Unix 服务器并重置用户密码。所以我尝试实现了SO中找到的一些代码。

例如

Sending commands to remote server through ssh by Java with JSch
Take commands(password) from string and set as InputStream to Unix servers in Java (JSCH)

使用 JSch ChannelExec，我按照 this link 获取了重置用户密码的正确命令。

当我尝试运行ning 这段代码时，它似乎没有重置用户密码。因此，我尝试运行直接从 Unix 的 shell 中调用命令，并且该命令运行良好。我假设 exec 根本没有工作。我将 exec 更改为运行一个像 mkdir /home/fikrie/testingjsch 这样的简单命令，然后证明我的假设，看到该目录没有创建。

这是我的代码：

public void executeSetPassword(final String userName, final GuardedString password)  {
    JSch jsch = new JSch();
    String host = configuration.getHost();
    String remoteUser = configuration.getRemoteUser();
    GuardedString passwd = configuration.getPassword();
    String command = "echo " + userName + ":" + password + " | chpasswd";
    Boolean sessionStatus, channelStatus;

    logger.info("userName is " + userName);
    logger.info("password is " + password);
    logger.info("command is " + command);

    final Session session;
    try {
        session = jsch.getSession(remoteUser, host, 22);

        passwd.access(new Accessor(){
            @Override
            public void access(char[] clearChars) {
                session.setPassword(new String(clearChars));
            }});
        Properties config = new Properties();
        config.put("StrictHostKeyChecking", "no");
        session.setConfig(config);
        session.connect();

        sessionStatus = session.isConnected();
        logger.info("sessionStatus is " + sessionStatus);
        ChannelExec channel=(ChannelExec) session.openChannel("exec");
        channel.setCommand(command);

        channel.connect();
        channelStatus = channel.isConnected();

        logger.info("channelStatus is " + channelStatus);
        logger.info("Exit status = " + channel.getExitStatus());

        channel.disconnect();
        session.disconnect();
    }
    catch (Exception e) {
        throw new RuntimeException(e);
    }
}

我到底错过了什么？会话和通道似乎还活着，但它不执行命令。这是代码的日志：

Method: executeSetPassword(UnixConnector.java:230)  Level: INFO Message: userName is anne
Method: executeSetPassword(UnixConnector.java:231)  Level: INFO Message: password is org.identityconnectors.common.security.GuardedString@e492109
Method: executeSetPassword(UnixConnector.java:232)  Level: INFO Message: command is echo anne:org.identityconnectors.common.security.GuardedString@e492109 | chpasswd
Method: executeSetPassword(UnixConnector.java:249)  Level: INFO Message: sessionStatus is true
Method: executeSetPassword(UnixConnector.java:257)  Level: INFO Message: channelStatus is true
Method: executeSetPassword(UnixConnector.java:258)  Level: INFO Message: Exit status = -1

这是 JSch 日志：

INFO: Connecting to 192.168.1.62 port 22
INFO: Connection established
INFO: Remote version string: SSH-2.0-OpenSSH_5.3
INFO: Local version string: SSH-2.0-JSCH-0.1.53
INFO: CheckCiphers: aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,3des-ctr,arcfour,arcfour128,arcfour256
INFO: aes256-ctr is not available.
INFO: aes192-ctr is not available.
INFO: aes256-cbc is not available.
INFO: aes192-cbc is not available.
INFO: CheckKexes: diffie-hellman-group14-sha1,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521
INFO: CheckSignatures: ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
INFO: SSH_MSG_KEXINIT sent
INFO: SSH_MSG_KEXINIT received
INFO: kex: server: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
INFO: kex: server: ssh-rsa,ssh-dss
INFO: kex: server: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
INFO: kex: server: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
INFO: kex: server: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
INFO: kex: server: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
INFO: kex: server: none,zlib@openssh.com
INFO: kex: server: none,zlib@openssh.com
INFO: kex: server: 
INFO: kex: server: 
INFO: kex: client: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1
INFO: kex: client: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
INFO: kex: client: aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc
INFO: kex: client: aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc
INFO: kex: client: hmac-md5,hmac-sha1,hmac-sha2-256,hmac-sha1-96,hmac-md5-96
INFO: kex: client: hmac-md5,hmac-sha1,hmac-sha2-256,hmac-sha1-96,hmac-md5-96
INFO: kex: client: none
INFO: kex: client: none
INFO: kex: client: 
INFO: kex: client: 
INFO: kex: server->client aes128-ctr hmac-md5 none
INFO: kex: client->server aes128-ctr hmac-md5 none
INFO: SSH_MSG_KEXDH_INIT sent
INFO: expecting SSH_MSG_KEXDH_REPLY
INFO: ssh_rsa_verify: signature true
WARN: Permanently added '192.168.1.62' (RSA) to the list of known hosts.
INFO: SSH_MSG_NEWKEYS sent
INFO: SSH_MSG_NEWKEYS received
INFO: SSH_MSG_SERVICE_REQUEST sent
INFO: SSH_MSG_SERVICE_ACCEPT received
INFO: Authentications that can continue: gssapi-with-mic,publickey,keyboard-interactive,password
INFO: Next authentication method: gssapi-with-mic
INFO: Authentications that can continue: publickey,keyboard-interactive,password
INFO: Next authentication method: publickey
INFO: Authentications that can continue: password
INFO: Next authentication method: password
INFO: Authentication succeeded (password).
INFO: Disconnecting from 192.168.1.62 port 22
INFO: Caught an exception, leaving main loop due to Socket closed

Answer 1

我假设问题是您甚至在命令启动之前就关闭了连接。

您指向的所有示例都读取命令输出，直到结束（因此直到命令完成）。您没有读取输出，因此无法等待命令完成。

像其他示例一样使用命令输出。或者（如果您对输出不感兴趣）等到 channel.isClosed() 为真后再退出。

我的 JSch 会话不执行命令

My JSch session doesn't execute command

java

unix

ssh

jsch