@@ -1,6 +1,5 @@ module Crypt class XXTEA - VERSION = '1.2.0' DELTA = 0x9E3779B9 def initialize(new_key) @@ -18,7 +17,8 @@ module Crypt end end - def self.str_to_longs(s, include_count = false) + def self.str_to_longs(s, include_count = false) # :nodoc: + s = s.dup length = s.length ((4 - s.length % 4) & 3).times { s << "\0" } # Pad to a multiple of 4 unpacked = s.unpack('V*').collect { |n| int32 n } @@ -26,41 +26,49 @@ module Crypt unpacked end - def str_to_longs(s, include_count = false) + def str_to_longs(s, include_count = false) # :nodoc: self.class.str_to_longs s, include_count end ## # convert array of longs back to string - def self.longs_to_str(l, count_included = false) + def self.longs_to_str(l, count_included = false) # :nodoc: s = l.pack('V*') s = s[0...(l[-1])] if count_included s end - def longs_to_str(l, count_included = false) + def longs_to_str(l, count_included = false) # :nodoc: self.class.longs_to_str l, count_included end - def self.int32(n) + def self.int32(n) # :nodoc: n -= 4_294_967_296 while (n >= 2_147_483_648) n += 4_294_967_296 while (n <= -2_147_483_648) n.to_i end - def int32(n) + def int32(n) # :nodoc: self.class.int32 n end - def mx(z, y, sum, p, e) + def mx(z, y, sum, p, e) # :nodoc: int32( ((z >> 5 & 0x07FFFFFF) ^ (y << 2)) + ((y >> 3 & 0x1FFFFFFF) ^ (z << 4)) ) ^ int32((sum ^ y) + (@key[(p & 3) ^ e] ^ z)) end + ## + # Encrypt the +plaintext+ using the +key+ + def self.encrypt(key, plaintext) + self.new(key).encrypt(plaintext) + end + + ## + # Encrypt the +plaintext+ def encrypt(plaintext) return '' if plaintext.length == 0 @@ -93,9 +101,14 @@ module Crypt longs_to_str(v).unpack('a*').pack('m').delete("\n") # base64 encode it without newlines end - # - # decrypt: Use Corrected Block TEA to decrypt ciphertext using password - # + ## + # Decrypt the +ciphertext+ using the +key+ + def self.decrypt(key, ciphertext) + self.new(key).decrypt(ciphertext) + end + + ## + # Decrypt the +ciphertext+ def decrypt(ciphertext) return '' if ciphertext.length == 0 lib/crypt_tea/xxtea.rb @@ -1,42 +1,62 @@ -$:.unshift File.dirname(__FILE__) + '/../lib' +require 'rubygems' +require 'minitest/spec' +require File.join(File.dirname(__FILE__), *%w[.. lib crypt_tea]) -require 'test/unit' -require 'crypt_tea' +MiniTest::Unit.autorun -class XXTEATest < Test::Unit::TestCase - def setup - @key = Crypt::XXTEA.new 'abigfattestkey' +describe Crypt::XXTEA do + before do + @key_text = 'abigfattestkey' + @key = Crypt::XXTEA.new @key_text @plaintext = "Oh say can you see, by the dawn's early light" @cyphertext = "V32cYZc5yLXepm9lxzr4kgGM/eSVurwV0yQWi4uFs0uB2UBlJ19ZRKKMkbMr7DLGc3n1XQ==" end - def test_str_to_long - assert_equal [1953719668, 6778473, 7], Crypt::XXTEA.str_to_longs('testing', true) + it 'converts strings to longs' do + Crypt::XXTEA.str_to_longs('testing', true).must_equal [1953719668, 6778473, 7] end - def test_longs_to_str - assert_equal 'testing', Crypt::XXTEA.longs_to_str([1953719668, 6778473, 7], true) + it 'converts longs to strings' do + Crypt::XXTEA.longs_to_str([1953719668, 6778473, 7], true).must_equal 'testing' end - def test_key_length - assert_raise(RuntimeError) { Crypt::XXTEA.new '12345678901234567' } - assert_raise(RuntimeError) { Crypt::XXTEA.new '' } + it 'raises an error when the key is too long' do + proc { Crypt::XXTEA.new '12345678901234567' }.must_raise RuntimeError end - def test_encrypt - assert_equal @cyphertext, @key.encrypt(@plaintext) + it 'raises an error when the key is blank' do + proc { Crypt::XXTEA.new '' }.must_raise RuntimeError end - def test_decrypt - assert_equal @plaintext, @key.decrypt(@cyphertext) + it 'works properly with small keys' do + key = Crypt::XXTEA.new '123' + cyphertext = key.encrypt(@plaintext) + key.decrypt(cyphertext).must_equal @plaintext end - def test_tiny_plaintext - assert_equal '1', @key.decrypt(@key.encrypt('1')) + it 'properly encrypts when instantiated' do + @key.encrypt(@plaintext).must_equal @cyphertext end - def test_huge_plaintext + it 'properly decrypts when instantiated' do + @key.decrypt(@cyphertext).must_equal @plaintext + end + + it 'properly en/decrypts tiny text' do + txt = '1' + @key.decrypt(@key.encrypt(txt)).must_equal txt + end + + it 'properly en/decrypts huge text' do str = '1234567890' * 1_000 - assert_equal str, @key.decrypt(@key.encrypt(str)) + @key.decrypt(@key.encrypt(str)).must_equal str + end + + it 'properly encrypts with a class method' do + Crypt::XXTEA.encrypt(@key_text, @plaintext).must_equal @cyphertext + end + + it 'properly decrypts with a class method' do + Crypt::XXTEA.decrypt(@key_text, @cyphertext).must_equal @plaintext end end \ No newline at end of file test/test_xxtea.rb b7cfcabfc659bc97cfdc3fd90ff446c6257a0d1f Jeff Smick sprsquish@gmail.com http://github.com/sprsquish/crypt--xxtea/commit/4658c2f22bdd9a1e7478fa0931455a7e87296571 4658c2f22bdd9a1e7478fa0931455a7e87296571 2009-06-05T13:40:41-07:00 2009-06-05T13:40:41-07:00 Update for documentation. dup incoming strings to str_to_longs so they aren't ruined with padding add a couple class methods for en/decrypting c4c247237bbbbdbc0ee6e9a83ef181399067c14a Jeff Smick sprsquish@gmail.com