(MFC) Fortuna PRNG Generate Random Encoded

Demonstrates how to generate random bytes using the Fortuna PRNG. The random bytes are returned in an encoded string (using an encoding such as hex, base64, base58, etc.)

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkGlobal.h>
#include <CkPrng.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // All Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    CkGlobal chilkatGlob;
    bool success = chilkatGlob.UnlockBundle("Anything for 30-day trial.");
    if (success != true) {
        strOut.append(chilkatGlob.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkPrng fortuna;

    // Before beginning to generate random data, 
    // the PRNG (Pseudo Random Number Generator) should
    // be seeded with real random data (also known as "entropy").

    // Note: Accumulating real random data can be difficult
    // and time-consuming to collect.  It is for this reason
    // that pseudorandom data (i.e. a PRNG) is used.  The pseudorandom data generator
    // is seeded with entropy.  In addition, new entropy can (and should)
    // be periodically added as more pseudorandom data is generated.

    // Get 32 bytes of system entropy.  On Linux/Unix systems, this reads
    // from /dev/random.  On MS Windows systems, it uses the Crypto API's 
    // CryptGenRandom function.
    const char *strEntropy = fortuna.getEntropy(32,"hex");
    if (fortuna.get_LastMethodSuccess() != true) {
        strOut.append(fortuna.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Seed the PRNG with this entropy:
    success = fortuna.AddEntropy(strEntropy,"hex");
    if (success != true) {
        strOut.append(fortuna.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Generate some random data:
    const char *strRandHex = fortuna.genRandom(16,"hex");
    const char *strRandBase64 = fortuna.genRandom(22,"base64");
    const char *strRandBase58 = fortuna.genRandom(32,"base58");

    strOut.append("hex random bytes: ");
    strOut.append(strRandHex);
    strOut.append("\r\n");
    strOut.append("base64 random bytes: ");
    strOut.append(strRandBase64);
    strOut.append("\r\n");
    strOut.append("base58 random bytes: ");
    strOut.append(strRandBase58);
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }