cipher.rb   [plain text]

=begin
= $RCSfile$ -- Ruby-space predefined Cipher subclasses

= Info
  'OpenSSL for Ruby 2' project
  Copyright (C) 2002  Michal Rokos <m.rokos@sh.cvut.cz>
  All rights reserved.

= Licence
  This program is licenced under the same licence as Ruby.
  (See the file 'LICENCE'.)

= Version
  $Id: cipher.rb 12496 2007-06-08 15:02:04Z technorama $
=end

##
# Should we care what if somebody require this file directly?
#require 'openssl'

module OpenSSL
  class Cipher
    %w(AES CAST5 BF DES IDEA RC2 RC4 RC5).each{|name|
      klass = Class.new(Cipher){
        define_method(:initialize){|*args|
          cipher_name = args.inject(name){|n, arg| "#{n}-#{arg}" }
          super(cipher_name)
        }
      }
      const_set(name, klass)
    }

    %w(128 192 256).each{|keylen|
      klass = Class.new(Cipher){
        define_method(:initialize){|mode|
          mode ||= "CBC"
          cipher_name = "AES-#{keylen}-#{mode}"
          super(cipher_name)
        }
      }
      const_set("AES#{keylen}", klass)
    }

    # Generate, set, and return a random key.
    # You must call cipher.encrypt or cipher.decrypt before calling this method.
    def random_key
      str = OpenSSL::Random.random_bytes(self.key_len)
      self.key = str
      return str
    end

    # Generate, set, and return a random iv.
    # You must call cipher.encrypt or cipher.decrypt before calling this method.
    def random_iv
      str = OpenSSL::Random.random_bytes(self.iv_len)
      self.iv = str
      return str
    end

    # This class is only provided for backwards compatibility.  Use OpenSSL::Digest in the future.
    class Cipher < Cipher
      # add warning
    end
  end # Cipher
end # OpenSSL