rng.h

Go to the documentation of this file.

// rng.h - written and placed in the public domain by Wei Dai


#ifndef CRYPTOPP_RNG_H
#define CRYPTOPP_RNG_H

#include "cryptlib.h"
#include "filters.h"
#include "smartptr.h"

NAMESPACE_BEGIN(CryptoPP)

class LC_RNG : public RandomNumberGenerator
{
public:
        LC_RNG(word32 init_seed)
                : seed(init_seed) {}

        void GenerateBlock(byte *output, size_t size);

        word32 GetSeed() {return seed;}

private:
        word32 seed;

        static const word32 m;
        static const word32 q;
        static const word16 a;
        static const word16 r;
};

class CRYPTOPP_DLL X917RNG : public RandomNumberGenerator, public NotCopyable
{
public:
        X917RNG(BlockTransformation *cipher, const byte *seed, const byte *deterministicTimeVector = 0);

        void GenerateIntoBufferedTransformation(BufferedTransformation &target, const std::string &channel, lword size);

private:
        member_ptr<BlockTransformation> m_cipher;
        const unsigned int m_size;  // S, blocksize of cipher
        SecByteBlock m_datetime;    // DT, buffer for enciphered timestamp
        SecByteBlock m_randseed, m_lastBlock, m_deterministicTimeVector;
};

class MaurerRandomnessTest : public Bufferless<Sink>
{
public:
        MaurerRandomnessTest();

        size_t Put2(const byte *inString, size_t length, int messageEnd, bool blocking);

        // BytesNeeded() returns how many more bytes of input is needed by the test
        // GetTestValue() should not be called before BytesNeeded()==0
        unsigned int BytesNeeded() const {return n >= (Q+K) ? 0 : Q+K-n;}

        // returns a number between 0.0 and 1.0, describing the quality of the
        // random numbers entered
        double GetTestValue() const;

private:
        enum {L=8, V=256, Q=2000, K=2000};
        double sum;
        unsigned int n;
        unsigned int tab[V];
};

NAMESPACE_END

#endif