class Net::SSH::Transport::Kex::Abstract

def generate_key_fingerprint(key)
  blob = Net::SSH::Buffer.from(:key, key).to_s
  fingerprint = Net::SSH::Authentication::PubKeyFingerprint.fingerprint(blob, @connection.options[:fingerprint_hash] || 'SHA256')
  [blob, fingerprint]
rescue StandardError => e
  [nil, "(could not generate fingerprint: #{e.message})"]
end