I can’t decrypt cipher created ny another application

[User (Old forums)]

#42982 |

Hello All,
I have one trouble with Xceed Encryption library v1.1.
I use the appropriate ActiveX component from both VB6.0 and visual C++ (VS2005) applications. But cypher created by VB application can’t be decrypted in vc++ application. Both projects use one ActiveX component but result a different encrypted cyphers. The created cyphers are simply with a different lengths.
Here is my code from VB6.0:
Private Sub Class_Initialize()

    Randomize Timer

    EMBEDDELIM = Chr$(255)

    ‘— initialize the XCeed encryption libs

    mbySecretKey(1) = &HA
    mbySecretKey(2) = &HA
    mbySecretKey(3) = &HA
    mbySecretKey(4) = &HA
    mbySecretKey(5) = &HA
    mbySecretKey(6) = &HA
    mbySecretKey(7) = &HA
    mbySecretKey(8) = &HA
    mbySecretKey(9) = &HA
    mbySecretKey(10) = &HA
    mbySecretKey(11) = &HA
    mbySecretKey(12) = &HA
    mbySecretKey(13) = &HA
    mbySecretKey(14) = &HA
    mbySecretKey(15) = &HA
    mbySecretKey(16) = &HA

    Set mxcEncrypt = New XceedEncryptionLib.XceedEncryption
    Set mxcMethod = New XceedEncryptionLib.XceedTwofishEncryptionMethod

    ‘— License the library for run-time use.
    Call mxcEncrypt.License(“My license code”)
   
    ‘— Initialize the encoder.
    mxcMethod.EncryptionMode = emoFreeBlocks
    mxcMethod.SecretKey = mbySecretKey
    mxcMethod.SetInitVectorFromPassPhrase TWOFISHVECTOR

    Set mxcEncrypt.EncryptionMethod = mxcMethod

    Exit Sub
End Sub

Public Function EncryptStringToHexString(ByVal sSource As String) As String
    Dim b()                     As Byte
    Dim bOut()                  As Byte
    Dim lLenIn                  As Long
    Dim lLBound                 As Long
   

    If (Len(sSource) > 0) Then
        soso = Len(sSource)
        b() = mxcEncrypt.Encrypt(sSource, True)
        lLBound = LBound(b())
       
        lLenIn = UBound(b()) – lLBound + 1
        ‘== !!!!!!!!!!!!!!!!!!!!   lLenIn is equal 2064 bytes and Len(sSource) is equal 1024 bytes

    End If
    Exit Function
End Function

Here is my code in vc++
void CEncryptTesterWithAXDlg::EncryptData(const char* pszSource)
{
    CoInitialize( NULL );

    try
    {
      IXceedEncryptionPtr piEnc;

      piEnc.CreateInstance( CLSID_XceedEncryption );
      piEnc->License( _bstr_t( _T(“My license code”) ) );

      IXceedTwofishEncryptionMethodPtr twoFish;
      BYTE mbySecretKey[SECRETKEYLENGTH] = {0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA, 0xA};

      twoFish.CreateInstance( CLSID_XceedTwofishEncryptionMethod ); 
      twoFish->SetSecretKey(mbySecretKey, SECRETKEYLENGTH);
      twoFish->EncryptionMode = emoFreeBlocks;
      twoFish->SetInitVectorFromPassPhrase(_bstr_t(TWOFISHVECTOR));

      piEnc->EncryptionMethod = IXceedEncryptDataPtr( twoFish ); 

      DWORD dwSourceSize = lstrlen( pszSource ) + 1; // Let’s say we want to encrypt the null-char too
      BYTE* pcEncrypted = NULL;
      DWORD dwEncryptedSize = 0; 

      piEnc->Encrypt( ( BYTE* )pszSource, dwSourceSize, TRUE, &pcEncrypted, &dwEncryptedSize ); 
      ‘== !!!!!!!!!!!!!!!!!!!!   for the same source string dwEncryptedSize is equal only 1040 bytes and Len(sSource) is equal 1024 bytes as well.

      CoTaskMemFree( pcEncrypted );
    }
    catch( const _com_error& xErr )
    {
      char szMsg[50];
      wsprintf( szMsg, “Error %08x\n”, xErr.Error() );
    }
    catch( … )
    {
      ;//MessageBox( NULL, “Unknown error”, “Error”, MB_OK );
    }

    CoUninitialize();
}

Can you explain why Xceed encryption ActiveX works so differently for the different IDE?
I use the same sekret key and initial vectors and algorithm and my goal is to generate the same cyphers from the both VB 6.0 and visual studio 2005 appliactions.

Imported from legacy forums. Posted by Dereak (had 4170 views)

[User (Old forums)]

#42983

If you are testing this with a string, both will not produce the same result, since in C++ a string is ANSI, whereas in VB it is Unicode.  Make sure to use the same encoding, or test this with binary data, and it should work fine.

Imported from legacy forums. Posted by André (had 405 views)

[User (Old forums)]

#42984

I see. Thank you.

In c++ I use this way for the data encryption:

        LPOLESTR wsz;
        AnsiToUnicode(pszSource, &wsz);
        dwSourceSize = lstrlenW( wsz );

        BYTE* pcEncrypted = NULL;
        DWORD dwEncryptedSize = 0; 

        m_xceedEncryption->Encrypt( (BYTE*)wsz, 2 * dwSourceSize, TRUE, &pcEncrypted, &dwEncryptedSize );  

And this way for decrypting data:

        LPCOLESTR pcDecrypted = NULL;
        DWORD dwDecryptedSize = 0; 

        m_xceedEncryption->Decrypt( sourceUnprotected, unprotectedSourceLen, TRUE, (BYTE**)&pcDecrypted, &dwDecryptedSize );

        LPSTR pcDecryptedStr = NULL;
        UnicodeToAnsi(pcDecrypted, &pcDecryptedStr);

Imported from legacy forums. Posted by Dereak (had 5607 views)

[Author]

Posts