How to perform Triple DES calculations in Ruby in hexadecimal?

Question

I'm trying to do some triple DES encryption in Ruby. I'm trying to replicate the results from this page: http://da.nmilne.com/des.html

I'm trying to replicate those result in Ruby. I suspect the problem is the key is supposed to be a string, but I need to pass in a Hexadecimal key. Either that or the string being encrypted is in the wrong format. Or maybe both. :-)

require 'openssl'
des = OpenSSL::Cipher::Cipher.new("des-ede-cbc")
des.encrypt
des.key="23232323232323234545454545454545"
des.update("0000000000000000")
res=des.final
res.unpack('H*')  
=> ["5045c5d37ca4d13b"]

But it should be:

=> ["3a42d7a1d1c60c40"]

Any pointers on where I'm going wrong?

• Different 3DES algorithms are documented here: http://www.openssl.org/docs/apps/enc.html
• Edited for clarity

Answer 1

The key is in hex - if you look at the Java page you pasted you can see that easily by decoding the binary values for the key in the detailed output.

>> des_cbc=OpenSSL::Cipher::Cipher.new("des-ede-cbc")
=> #<OpenSSL::Cipher::Cipher:0x10116ce28>
>> des_cbc.encrypt
=> #<OpenSSL::Cipher::Cipher:0x10116ce28>
>> des_cbc.key="\x23"*8 << "\x45"*8
=> "########EEEEEEEE"
>> des_cbc.update("\x00"*8).unpack('H*')
=> ["3a42d7a1d1c60c40"]