There's FTP/S (and RFC-4217, and not SFTP), which uses an SSL session negotiated inside of an FTP session. I don't know if there's a client/server combo that s

There's FTP/S (and RFC-4217, and not SFTP), which uses an SSL session negotiated inside of an FTP session. I don't know if there's a client/server combo that supports pinning, but this much at least exists. Frankly, if I was looking to implement this, I'd start with SFTP/SCP. FTP/S is, at best, a rarely implemented kludge.