# File lib/net/ssh/transport/cipher_factory.rb, line 69
    def self.get(name, options={})
      ossl_name = SSH_TO_OSSL[name] or raise NotImplementedError, "unimplemented cipher `#{name}'"
      return IdentityCipher if ossl_name == "none"
      cipher = OpenSSL::Cipher::Cipher.new(ossl_name)

      cipher.send(options[:encrypt] ? :encrypt : :decrypt)

      cipher.padding = 0

      cipher.extend(Net::SSH::Transport::CTR) if (name =~ /-ctr(@openssh.org)?$/)

      cipher.iv      = Net::SSH::Transport::KeyExpander.expand_key(cipher.iv_len, options[:iv], options) if ossl_name != "rc4"

      key_len = KEY_LEN_OVERRIDE[name] || cipher.key_len
      cipher.key_len = key_len
      cipher.key     = Net::SSH::Transport::KeyExpander.expand_key(key_len, options[:key], options)
      cipher.update(" " * 1536) if (ossl_name == "rc4" && name != "arcfour")

      return cipher
    end