JSch 算法协商失败

Question

我尝试通过 Java 连接 SFTP 服务器。

我收到一个错误。

com.jcraft.jsch.JSchException: Algorithm negotiation fail

这是 POM：

<dependency>
            <groupId>com.jcraft</groupId>
            <artifactId>jsch</artifactId>
            <version>0.1.53</version>
</dependency>

这是日志：

INFO: Connecting to **"FTP ADRESS"** port 22
INFO: Connection established
INFO: Remote version string: SSH-2.0-Maverick_SSHD
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: diffie-hellman-group14-sha1 is not available.
INFO: ecdh-sha2-nistp256 is not available.
INFO: ecdh-sha2-nistp384 is not available.
INFO: ecdh-sha2-nistp521 is not available.
INFO: CheckSignatures: ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
INFO: ecdsa-sha2-nistp256 is not available.
INFO: ecdsa-sha2-nistp384 is not available.
INFO: ecdsa-sha2-nistp521 is not available.
INFO: SSH_MSG_KEXINIT sent
INFO: SSH_MSG_KEXINIT received
INFO: kex: server: diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha1
INFO: kex: server: ssh-rsa
INFO: kex: server: aes256-cbc,aes192-cbc
INFO: kex: server: aes256-cbc,aes192-cbc
INFO: kex: server: hmac-sha1,hmac-sha1-96
INFO: kex: server: hmac-sha1,hmac-sha1-96
INFO: kex: server: none
INFO: kex: server: none
INFO: kex: server: 
INFO: kex: server: 
INFO: kex: client: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1
INFO: kex: client: ssh-rsa,ssh-dss
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: Disconnecting from "FTP ADRESS" port 22

我遇到了这个错误，我试图修复它。我无法访问 SFTP 服务器以下载或更新任何文件等...

我可以通过 FileZilla 连接服务器，但我无法通过 Java 连接。

连接代码：

JSch jsch = new JSch();
Properties config = new Properties();
config.put("cipher.s2c", 
           "aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,aes192-ctr,aes192-cbc,aes256-ctr,aes256-cbc");
config.put("cipher.c2s",
           "aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,aes192-ctr,aes192-cbc,aes256-ctr,aes256-cbc");
config.put("kex", "diffie-hellman-group1-sha1,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group-exchange-sha256");
Session jschSession = jsch.getSession("username","server",22);

jschSession.setConfig("StrictHostKeyChecking", "no");
jschSession.setPassword("password");
jschSession.setConfig(config);
jschSession.connect();

当我添加

config.put("cipher.s2c", 
           "aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,aes192-ctr,aes192-cbc,aes256-ctr,aes256-cbc");

日志是这样的

INFO: Connecting to ftp.servername port 22
INFO: Connection established
INFO: Remote version string: SSH-2.0-Maverick_SSHD
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: diffie-hellman-group14-sha1 is not available.
INFO: ecdh-sha2-nistp256 is not available.
INFO: ecdh-sha2-nistp384 is not available.
INFO: ecdh-sha2-nistp521 is not available.
INFO: CheckSignatures: ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
INFO: ecdsa-sha2-nistp256 is not available.
INFO: ecdsa-sha2-nistp384 is not available.
INFO: ecdsa-sha2-nistp521 is not available.
INFO: SSH_MSG_KEXINIT sent
INFO: SSH_MSG_KEXINIT received
INFO: kex: server: diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha1
INFO: kex: server: ssh-rsa
INFO: kex: server: aes256-cbc,aes192-cbc
INFO: kex: server: aes256-cbc,aes192-cbc
INFO: kex: server: hmac-sha1,hmac-sha1-96
INFO: kex: server: hmac-sha1,hmac-sha1-96
INFO: kex: server: none
INFO: kex: server: none
INFO: kex: server: 
INFO: kex: server: 
INFO: kex: client: diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group-exchange-sha256
INFO: kex: client: ssh-rsa,ssh-dss
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: Disconnecting from ftp.servername port 22
com.jcraft.jsch.JSchException: Algorithm negotiation fail

Answer 1

如您所见，服务器提供了这些密码：

INFO: kex: server: aes256-cbc,aes192-cbc

但 JSch 只接受这些：

INFO: kex: client: aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc

没有通用密码可供选择。

请注意，JSch 确实支持 aes256-cbc 和 aes192-cbc，但需要 JCE（Java 加密扩展）来允许它们。

您可能没有 JCE，因此这些密码不可用。这就是为什么

INFO: aes256-cbc is not available.

下载Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files 8 (or other version if other JDK – 1.7, 1.6, IBM JDK 1.6).

另请参阅 The cipher 'aes256-cbc' is required, but it is not available 的答案。

Answer 2

我通过在 /etc/ssh/sshd_config 中添加以下行并重新启动 sshd 服务来解决它。感谢 answer by @wierzbiks at another thread

KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1

Answer 3

我解决了更新库 jsch-0.1.27.jar 到 jsch-0.1.54.jar.

最后在你的代码中你应该这样写：

your Method {       
     session.setConfig("StrictHostKeyChecking", "no");
// That solve the problem.
    }

如果您需要此 java 版本，此代码适用于 Java 1.5 或更高版本。

JSch 算法协商失败

JSch Algorithm negotiation fail

java

connection

sftp

jsch