var preferredCiphers = []string{
	"******@****.***", gcm256CipherID,
	chacha20Poly1305ID,
	"aes128-ctr", "aes192-ctr", "aes256-ctr",
}

// supportedMACs specifies a default set of MAC algorithms in preference order.
// This is based on RFC 4253, section 6.4, but with hmac-md5 variants removed
// because they have reached the end of their useful life.