Token masking benchmark

benchmark.rb

require 'benchmark'

require 'securerandom'
require 'base64'
require 'bcrypt'

BCrypt::Engine.cost = 1
length = 32
token_from_session = SecureRandom.base64(length)

Benchmark.bmbm do |x|
  x.report 'xor' do
    master_csrf_token = Base64.strict_decode64(token_from_session)
    one_time_pad = SecureRandom.random_bytes(length)
    encrypted_csrf_token = one_time_pad.bytes.zip(master_csrf_token.bytes).map { |c1,c2| c1 ^ c2 }.pack('c*')
    one_time_pad.concat(encrypted_csrf_token)
    Base64.strict_encode64(one_time_pad)
  end

  x.report 'salt + sha1' do
    master_csrf_token = Base64.strict_decode64(token_from_session)
    salt = SecureRandom.random_bytes(length)
    digest = Digest::SHA1.new
    digest.update(salt)
    digest.update(master_csrf_token)
    salt.concat(digest.digest)
    Base64.strict_encode64(salt)
  end

  x.report 'salt + md5' do
    master_csrf_token = Base64.strict_decode64(token_from_session)
    salt = SecureRandom.random_bytes(length)
    digest = Digest::MD5.new
    digest.update(salt)
    digest.update(master_csrf_token)
    salt.concat(digest.digest)
    Base64.strict_encode64(salt)
  end

  x.report 'bcrypt' do
    BCrypt::Password.create(token_from_session)
  end
end

results.txt

Rehearsal -----------------------------------------------
xor           0.000000   0.000000   0.000000 (  0.000083)
salt + sha1   0.000000   0.000000   0.000000 (  0.000314)
salt + md5    0.000000   0.000000   0.000000 (  0.000250)
bcrypt        0.000000   0.000000   0.000000 (  0.001144)
-------------------------------------- total: 0.000000sec

                  user     system      total        real
xor           0.000000   0.000000   0.000000 (  0.000090)
salt + sha1   0.000000   0.000000   0.000000 (  0.000049)
salt + md5    0.000000   0.000000   0.000000 (  0.000038)
bcrypt        0.000000   0.000000   0.000000 (  0.001115)