在C＃中连接到AWS Managed SFTP服务器时SSH.NET超时

根据RFC 4253第4.2节。协议版本交换：

建立连接后，双方必须发送一个识别字符串。

Both SSH.NET client and Amazon Managed SFTP server fail this requirement. Both first wait for the other side to send the identification string before sending its own. A deadlock is inevitable (interrupted only by a timeout). That also explains why Wireshark does not identify the session as SSH, as there's no data exchanged at all. Hence, there's nothing by which the protocol can be identified.

If you can modify SSH.NET source code, moving this line in Session.Connect:

SocketAbstraction.Send(_socket, Encoding.UTF8.GetBytes(string.Format(CultureInfo.InvariantCulture, "{0}\x0D\x0A", ClientVersion)));

... above this block:

Match versionMatch;

//  Get server version from the server,
//  ignore text lines which are sent before if any
while (true)
{
    ...
}

... should fix the problem.

Also consider reporting the bug to Amazon.

I have reported the bug to SSH.NET including the needed change.

If you cannot change SSH.NET code, you will need to use another SFTP library.

例如，我的WinSCP .NET程序集与Amazon Managed SFTP服务器兼容。

这等效于您的代码：

// Set up session options
SessionOptions sessionOptions = new SessionOptions
{
    Protocol = Protocol.Sftp,
    HostName = baseHost,
    UserName = user,
    SshHostKeyFingerprint = ...,
    SshPrivateKeyPath = keyLocation,
    PrivateKeyPassphrase = pkpassword,
};

using (Session session = new Session())
{
    // Connect
    session.Open(sessionOptions);

    // Your code
}

WinSCP GUI可以为您生成类似于上面的代码模板。