#--
#
# $RCSfile$
#
# = 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 33067 2011-08-25 00:52:10Z drbrain $
#
#++

module OpenSSL
  class Cipher
    class CipherError < OpenSSLError; end

    def self.ciphers
      %w(AES AES128 AES192 AES256 CAST5 BF DES IDEA RC2 RC4 RC5)
    end

    ciphers.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::Cipher in the future.
    class Cipher < Cipher
      # add warning
    end
  end # Cipher
end # OpenSSL
