JezK
Edit File: securerandom.rb
# -*- coding: us-ascii -*- # frozen_string_literal: true require 'random/formatter' # == Secure random number generator interface. # # This library is an interface to secure random number generators which are # suitable for generating session keys in HTTP cookies, etc. # # You can use this library in your application by requiring it: # # require 'securerandom' # # It supports the following secure random number generators: # # * openssl # * /dev/urandom # * Win32 # # SecureRandom is extended by the Random::Formatter module which # defines the following methods: # # * alphanumeric # * base64 # * choose # * gen_random # * hex # * rand # * random_bytes # * random_number # * urlsafe_base64 # * uuid # # These methods are usable as class methods of SecureRandom such as # +SecureRandom.hex+. # # If a secure random number generator is not available, # +NotImplementedError+ is raised. module SecureRandom class << self def bytes(n) return gen_random(n) end private def gen_random_openssl(n) @pid = 0 unless defined?(@pid) pid = $$ unless @pid == pid now = Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond) OpenSSL::Random.random_add([now, @pid, pid].join(""), 0.0) seed = Random.urandom(16) if (seed) OpenSSL::Random.random_add(seed, 16) end @pid = pid end return OpenSSL::Random.random_bytes(n) end def gen_random_urandom(n) ret = Random.urandom(n) unless ret raise NotImplementedError, "No random device" end unless ret.length == n raise NotImplementedError, "Unexpected partial read from random device: only #{ret.length} for #{n} bytes" end ret end ret = Random.urandom(1) if ret.nil? begin require 'openssl' rescue NoMethodError raise NotImplementedError, "No random device" else alias gen_random gen_random_openssl end else alias gen_random gen_random_urandom end public :gen_random end end SecureRandom.extend(Random::Formatter)