From: Rob Biedenharn <Rob@...>
Date: 2010-07-02T03:39:50+09:00
Subject: Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby

On Jul 1, 2010, at 1:01 PM, Joshua Mckinney wrote:
> Rob Biedenharn wrote:
>> On Jul 1, 2010, at 11:34 AM, Joshua Mckinney wrote:
>>>>    final_key[i%16] ^= key[i]
>>>> => true
>>> ruby-1.9.1-p378 > key = "test_key"
>>>
>>> ruby-1.9.1-p378 >     final_key
>>> =>  
>>> "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
>>
>> Because in Ruby 1.8.6, "hello"[0] is 104, but in 1.8.7 and 1.9.x,
>> "hello"[0] is "h"
>>
>> Change that line to:
>>
>> final_key[i%16] = (final_key[i%16].ord ^ key[i].ord).chr
>>
>> And you should get the right answer:
>>
>> irb> x="hello"
>> => "hello"
>> irb> x[0] = (x[0].ord ^ 0x20).chr
>> => "H"
>> irb> x
>> => "Hello"
>>
>> String#ord gives the Fixnum value of a single-character string.
>> Fixnum#chr gives the single-character String whose #ord is the Fixnum
>>
>> (I'm sure the actual docs say that better ;-)
>>
>> -Rob
>>
>> Rob Biedenharn
>> http://agileconsultingllc.com
>>  Rob@AgileConsultingLLC.com
>> http://gaslightsoftware.com
>>  rab@GaslightSoftware.com
> Thanks for the reply, we got rid of the error in 1.9.1 but both 1.9.1
> and 1.8.7 produce the wrong final_key
>
> ruby-1.9.1-p378 >     final_key
> => "test key\x00\x00\x00\x00\x00\x00\x00\x00"
>
> ruby-1.8.7-p174 >     final_key
> => "test key\000\000\000\000\000\000\000\000"
>
> -- 
> Posted via http://www.ruby-forum.com/.
>

What final_key do you expect?  You need to post the full code and  
input along with the expected value (or what 1.8.6 gives?) in order to  
help.

-Rob