#-- # sha2.rb - defines Digest::SHA2 class which wraps up the SHA256, # SHA384, and SHA512 classes. #++ # Copyright (c) 2006 Akinori MUSHA # # All rights reserved. You can redistribute and/or modify it under the same # terms as Ruby. # # $Id: sha2.rb 11708 2007-02-12 23:01:19Z shyouhei $ require 'digest' module Digest # # A meta digest provider class for SHA256, SHA384 and SHA512. # class SHA2 < Digest::Class # call-seq: # Digest::SHA2.new(bitlen = 256) -> digest_obj # # Creates a new SHA2 hash object with a given bit length. def initialize(bitlen = 256) case bitlen when 256 @sha2 = Digest::SHA256.new when 384 @sha2 = Digest::SHA384.new when 512 @sha2 = Digest::SHA512.new else raise ArgumentError, "unsupported bit length: %s" % bitlen.inspect end @bitlen = bitlen end # :nodoc: def reset @sha2.reset self end # :nodoc: def update(str) @sha2.update(str) self end alias << update def finish @sha2.digest! end private :finish def block_length @sha2.block_length end def digest_length @sha2.digest_length end # :nodoc: def initialize_copy(other) @sha2 = other.instance_eval { @sha2.clone } end # :nodoc: def inspect "#<%s:%d %s>" % [self.class.name, @bitlen, hexdigest] end end end