}
	return nil, nil
}

type cramMD5Auth struct {
	username, secret string
}

// CRAMMD5Auth returns an [Auth] that implements the CRAM-MD5 authentication
// mechanism as defined in RFC 2195.
// The returned Auth uses the given username and secret to authenticate
// to the server using the challenge-response mechanism.
func CRAMMD5Auth(username, secret string) Auth {
	return &cramMD5Auth{username, secret}
}