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I'm working on support for an extra algorithm. The algorithm consists of a few well knows hashing and encryption algorithms. I've successfully implemented most steps, recycling code of a bunch already available OpenCL kernels. However, I'm missing one step: DES decryption.
Perhaps the code is available and was removed by the developers of the DES-based algorithms (1500, 3000 etc.) since it's not used in the specific hash formats. If this is the case, can you please let me know?
Thanks a lot!
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For pure DES encryption or decryption you might want to check out the old DES oracle algorithm in -m 3100
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07-05-2016, 08:43 AM
(This post was last modified: 07-05-2016, 08:44 AM by John Doe.)
(07-05-2016, 08:15 AM)atom Wrote: For pure DES encryption or decryption you might want to check out the old DES oracle algorithm in -m 3100
The old Oracle hashing algorithm only usese DES encrypt, not decrypt...
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In DES, for decrypt, you just access the sboxes in reverse. See
http://www.scs.stanford.edu/histar/src/p...rypt/des.c how it handles de_keysl[] and en_keysl[]
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07-09-2016, 01:17 AM
(07-05-2016, 08:56 AM)atom Wrote: In DES, for decrypt, you just access the sboxes in reverse. See http://www.scs.stanford.edu/histar/src/p...rypt/des.c how it handles de_keysl[] and en_keysl[]
Winner winner chicken diner!
I was not aware of the reverse S boxes part. I've implemented '_des_decrypt_keysetup' with reverse filling of the Kc and Kd arrays and works like a charm.
Thanks for your reply!
John
