5

我构建了一个 Java 应用程序，它通过 ssh 运行命令。在第一次尝试中，我通过用户名和密码进行了身份验证，一切正常。

现在我想使用 Kerberos 密钥表文件进行身份验证，但这会产生问题！

这里对我的配置说几句：

  • KDC服务器：my-server.de
  • 领域名称：MYREALM.DE
  • 密钥表用户名：keytabuser
  • KDC = 服务器：运行在CentOS 7
  • 我的客户：安装Windows 8.1 (x64)了所有默认配置Kerberos for Windows
  • 我在客户端的用户名：Daniel
  • kinit -kt ...似乎工作正常，所以keytab文件也应该没问题

到目前为止，我所拥有的是这段代码片段：

public static void main(String[] args) {
        String host = "my-server.de";
        String user = "keytabuser";
        String  command = "ls -l";

        JSch jsch = new JSch();
        jsch.setLogger(new MyLogger());

        System.setProperty("java.security.krb5.conf", "C:\\ProgramData\\MIT\\Kerberos5\\krb5.ini");
        System.setProperty("java.security.auth.login.config", "C:\\ProgramData\\MIT\\Kerberos5\\jaas.conf");
        System.setProperty("javax.security.auth.useSubjectCredsOnly", "false");

        //to enable kerberos debugging mode
        System.setProperty("sun.security.krb5.debug", "true");

        try {
            Session session = jsch.getSession(user, host, 22);
            Properties config = new java.util.Properties();
            config.put("StrictHostKeyChecking", "no");
            config.put("PreferredAuthentications", "gssapi-with-mic");

            session.setConfig(config);
            session.connect(20000);

            Channel channel = session.openChannel("exec");
            ... // Do the commands

            channel.disconnect();
            session.disconnect();
            System.out.println("DONE");

        } catch (JSchException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
}

这是我的jaas.conf文件：

com.sun.security.jgss.krb5.initiate {
  com.sun.security.auth.module.Krb5LoginModule required
  doNotPrompt=true
  principal="keytabuser@MYREALM.DE"
  useKeyTab=true
  keyTab="C:\ProgramData\MIT\Kerberos5\keytabuser.keytab"
  storeKey=true;
};

这里是我的krb5.ini文件：

[libdefaults]
  default_realm = MYREALM.DE

[realms]
  MYREALM.DE = {
    admin_server = my-server.de
    kdc = my-server.de
  }

当我运行这个应用程序时，我得到以下输出：

更新：新 jsch 依赖 0.1.54 后的新控制台输出

INFO: Connecting to my-server.de port 22
INFO: Connection established
INFO: Remote version string: SSH-2.0-OpenSSH_6.6.1
INFO: Local version string: SSH-2.0-JSCH-0.1.54
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: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
INFO: kex: server: ssh-rsa,ecdsa-sha2-nistp256,ssh-ed25519
INFO: kex: server: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,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-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
INFO: kex: server: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
INFO: kex: server: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,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_KEX_ECDH_INIT sent
INFO: expecting SSH_MSG_KEX_ECDH_REPLY
INFO: ssh_rsa_verify: signature true
WARN: Permanently added 'my-server.de' (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
INFO: Next authentication method: gssapi-with-mic
INFO: Disconnecting from my-server.de port 22
com.jcraft.jsch.JSchException: Auth fail
    at com.jcraft.jsch.Session.connect(Session.java:519)
    at kerberos.JschKerberos.main(JschKerberos.java:49)

我的配置有问题吗？本地（用户、域等）和远程之间是否存在某些条件？

4

1 回答 1

4

我终于找到了解决方案！这是该服务缺少的服务密钥表sshd！某些服务主体不是由 Kerberos 服务器自动生成的。所以这必须由 kadmin 手动完成，因为sshd服务还必须针对 Kerberos 进行身份验证！这是由host/fqdn@REALM校长完成的。

这里很重要：“主机”是一个固定的字符串（！），我总是用我的 OpenSSH 服务器机器的主机名替换它......所以，只有“fqdn”和“REALM.COM”必须用您的数据替换！

所以这些是我获得应用程序工作的必要步骤：

  1. 在OpenSSH 服务器GSSAPIAuthentication yes的配置文件中设置/etc/ssh/sshd_conf
  2. 在ssh 客户端Host * [...] GSSAPIAuthentication yes的配置文件中设置/etc/ssh/ssh_conf
  3. 检查客户端上的jaas.conf和krb5.conf（或.ini）文件是否正确设置（请参阅上面问题部分中的代码块）
  4. 在 Kerberos 服务器上，打开kadmin.local并键入ktadd host/my-server.de
  5. 可选：添加用户主体（如果尚不存在）：ktadd keytabuser
  6. 制作一个kinit keytabuser（使用密码）或kinit -kt /path/to/file.keytab keytabuser（普通的 Kerberos 命令）
  7. 检查用户是否通过klist
  8. 通过控制台直接运行应用程序或 sshssh keytabuser@my-server.de
  9. 您应该通过缓存的票证登录！

当然，用户keytabuser必须是 ssh-server 机器上的用户！

于 2017-01-24T14:44:30.740 回答