[TIP] Visual C++ CAPICOM MD5

From: K D (samudbhava_at_gmail.com)
Date: 10/26/04

  • Next message: Phil Ten: "Re: CryptAcquireContext fails with error 6 (The handle is invalid)" 
    Date: 26 Oct 2004 03:03:01 -0700

    I searched google groups (and google as well) for 'IHashedDataPtr' ...
    finding nothing, I thought it was safe to go ahead and post this code.
     It shows the wrong and right way of generating md5 hash. It took me a
    while to figure this out and I hope it will save time for you.

    #import "capicom.dll" no_namespace
    :
    :
    void CEssImpl::HashTest()
    {
            // from: http://pajhome.org.uk/crypt/md5/
            // hello! => 5a8dd3ad0756a93ded72b823b19dd877

            IHashedDataPtr iHashedData(__uuidof(HashedData));
            iHashedData->Algorithm=CAPICOM_HASH_ALGORITHM_MD5;

            // data to hash
            CString data("hello!");

            // wrong way! gives => B38A88C2EEC50E7C31FF95A5BFDB9EF6
            _bstr_t t1=(_bstr_t)data;
            iHashedData->Hash(t1);
            cout << iHashedData->Value << endl;

            // right way! gives => 5A8DD3AD0756A93DED72B823B19DD877
            _bstr_t t2;
            t2.Assign(SysAllocStringByteLen(data, data.GetLength()));
            iHashedData->Hash(t2);
            
            cout << iHashedData->Value;
    }

  • Next message: Phil Ten: "Re: CryptAcquireContext fails with error 6 (The handle is invalid)"