hybrid encryption to encrypt large data with an rsa pubkey and aes

hybrid_encrypt

def self.encrypt(data, crt_pem)
  cert = OpenSSL::X509::Certificate.new(crt_pem)
  rsa = cert.public_key

  aes = OpenSSL::Cipher::Cipher.new('aes-256-cbc')
  aes.encrypt
  key = aes.random_key.unpack('H*')[0]
  iv  = aes.random_iv.unpack('H*')[0]

  ciphertext = aes.update(data)
  ciphertext << aes.final
  key = rsa.public_encrypt(key)
  iv = rsa.public_encrypt(iv)

  [ciphertext, key, iv].map {|o| Base64.encode64(o)}
end