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  • 1.  Other DES data encryption other than ENC?

    Posted 05/17/24 05:26 PM

    Hello.   I find myself looking to create a KCVfor a DES key.   I have code using ENC to create one for me.  It seems to require CBC and will not allow EBC.   And I'm wondering if using EBC would give me a different KCV result.   To that end, I've been looking for a data encryption call that would allow me to create KCV using EBC.  I can't find one in the application programmers guide.

    Would anyone else have ideas that would point me into a direction to accomplish this goal?

    Does anyone already know the CBC or EBC does not matter when generating a KCV?

    Your feedback to get me started on a solution for this would be appreciated.

    Sincerely,

    Mark Vollmer



    ------------------------------
    Mark Vollmer
    Developer, but does everything.
    CV Systems, LLC
    ------------------------------


  • 2.  RE: Other DES data encryption other than ENC?

    Posted 05/17/24 08:42 PM

    It usually doesn't matter for most kinds of KCVs. You might want to use CSNBKYT to generate key test values instead. CSNBENC will only work for data-encryption keys that are allowed to do encryption and will fail for keys like PINGEN, etc.



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    Eric Rossman
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  • 3.  RE: Other DES data encryption other than ENC?

    Posted 05/20/24 05:26 PM

    Eric,

    Thanks for helping out.   Is it  your belief that I can use ENC-ZERO in this BKYT call and an encrypted import/export key to create a KCV that was performed using ECB?

    Sincerely,

    Mark Vollmer



    ------------------------------
    Mark Vollmer
    Developer, but does everything.
    CV Systems, LLC
    ------------------------------

    Original Message


  • 4.  RE: Other DES data encryption other than ENC?

    Posted 05/21/24 01:41 PM

    Yes, that will work.

    I just tried it with a 16-byte DES key using both ECB and CBC (with an all zero IV) modes and got the same first 4 bytes as returned from CSNBKYT using rules 'KEY-ENCDGENERATEENC-ZERO'



    ------------------------------
    Eric Rossman
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    Original Message


  • 5.  RE: Other DES data encryption other than ENC?

    Posted 05/21/24 09:30 PM

    Eric,

    I can't thank you enough.   I too was able to perform the comparison and got the same KCV results. 

    Thanks very much.

    Sincerely,

    Mark Vollmer



    ------------------------------
    Mark Vollmer
    Developer, but does everything.
    CV Systems, LLC
    ------------------------------

    Original Message


  • 6.  RE: Other DES data encryption other than ENC?

    Posted 05/22/24 08:43 AM

    I'm so glad to hear that you were successful. I'm happy to help!



    ------------------------------
    Eric Rossman
    ------------------------------

    Original Message


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