enum KeyExchange {
  ftpKeyExchangeUnknown = 0,
  ftpKeyExchangeDiffieHellmanGroup14SHA1 = 2,
  ftpKeyExchangeDiffieHellmanGroupExchangeSHA1 = 3,
  ftpKeyExchangeDiffieHellmanGroupExchangeSHA256 = 4,
  ftpKeyExchangeDiffieHellmanGroup14SHA256 = 5,
  ftpKeyExchangeDiffieHellmanGroup16SHA512 = 6,
  ftpKeyExchangeECDH256 = 7,
  ftpKeyExchangeECDH384 = 8,
  ftpKeyExchangeECDH521 = 9,
  ftpKeyExchangeCurve25519 = 10
};