CryptoAPI and private key /not public/ encryption with CryptEncrypt - can not use CryptHash* functions

From: Przemek Wasylko (wasylek_at_remove-me.megapolis.pl)
Date: 12/26/04

  • Next message: Valery Pryamikov: "Re: CryptoAPI and private key /not public/ encryption with CryptEncrypt - can not use CryptHash* functions" 
    Date: Sun, 26 Dec 2004 15:08:00 +0100

    Hello All :)

    I have 3rd party library that supplies me with calculated by itself hash of
    some data (so I can not use CryptHashData, etc). I don't know hash method,
    I'm only supposed to encrypt that hash using private key in order to create
    digital signature. I have SmartCard CSP with public/private keypair stored
    on it. I would like to encrypt that SHA1 hash, but using private key not the
    public one (in order to have another party validate signature by using
    public key provided by me - i can extract public key from smartcard ). But
    unfortunatelly I have found no obvious way to do that by using CryptoAPI,
    maybe I am missing something. MSDN and other sources force me to use
    CryptCreateHash/CryptHashData/CryptSignHash, but, as I mentioned before, I
    can't do that (my code does not calculate hash). I would like to use
    CryptEncrypt with private key and CryptDecrypt with public key. Is there
    solution to my problem ?

    Best regards
    Przemek Wasylko

  • Next message: Valery Pryamikov: "Re: CryptoAPI and private key /not public/ encryption with CryptEncrypt - can not use CryptHash* functions"

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