bignum.h

“网络安全技术实践与代码详解”实例代码

// BigNum.h: interface for the CBigNum class.
//
//////////////////////////////////////////////////////////////////////

typedef unsigned long DWORD;
#ifndef NULL
#define NULL ((voind *)0)
#endif

class CBigNumString
{
public:
   CBigNumString();
   ~CBigNumString();
   operator const char *() const;
   void Realloc(unsigned int nByteCount);
   CBigNumString(const CBigNumString& rhs);
   char &operator [](unsigned int nIdx);
   const CBigNumString &operator=(const CBigNumString rhs);

private:
   char *m_szBuffer;
   unsigned int m_nSize;
};

class CBigNum  
{
public:
	CBigNum();
	CBigNum(unsigned int);
	CBigNum(const CBigNum &copy);
   CBigNum(const char *szSourceVal);
	virtual ~CBigNum();

	CBigNum Pow(unsigned int rhs) const;
   CBigNum PowMod(CBigNum rhs, const CBigNum &mod, const clock_t ctShowSteps = 0) const;
   CBigNum Inverse(const CBigNum &mod) const;
   unsigned int operator&(unsigned int rhs);
	void Resize(unsigned int nNewSize);
   void Reduce();

   CBigNum &operator=(CBigNum rhs);
   CBigNum &operator=(const char *szSourceVal);
   CBigNum &operator=(unsigned int intVal);
   CBigNum &operator<<=(unsigned int rhs);
   CBigNum operator<<(unsigned int rhs) const;
   CBigNum &operator>>=(unsigned int rhs);
   CBigNum operator>>(unsigned int rhs) const;
	CBigNum &operator+=(const CBigNum &rhs);
   CBigNum &operator-=(const CBigNum &rhs);
   CBigNum &operator-=(const unsigned int rhs);
   CBigNum operator-(const unsigned int rhs) const;
   CBigNum operator+(const CBigNum &rhs) const;
   CBigNum operator+(const unsigned int) const;
   CBigNum operator*(unsigned int rhs) const;
	CBigNum operator*(const CBigNum &rhs) const;
   CBigNum &operator*=(unsigned int rhs);
   CBigNum &operator*=(const CBigNum &rhs);
   CBigNum operator/(const CBigNum &rhs) const;
   CBigNum operator/(const unsigned int rhs) const;
   CBigNum &operator/=(const CBigNum &rhs);
   CBigNum &operator/=(const unsigned int rhs);
   CBigNum operator%(const CBigNum &rhs) const;
   unsigned int operator%(const unsigned int rhs) const;
   CBigNum &operator%=(const CBigNum &rhs);
   unsigned int operator%=(const unsigned int rhs);
   CBigNum &operator&=(CBigNum rhs);
   CBigNum &operator|=(const CBigNum &rhs);
   CBigNum operator|(const CBigNum &rhs) const;
   CBigNum &operator|=(const unsigned int rhs);
   CBigNum operator|(const unsigned int rhs) const;
   CBigNum factorial() const;
   CBigNum sqrt() const;
   unsigned int log10() const;
   unsigned int log2() const;

   static CBigNum gcd(const CBigNum &x, const CBigNum &y);
   static CBigNum lcm(const CBigNum &x, const CBigNum &y);
   static CBigNum FromByteString(const char *szIn, const unsigned int nLength = 0);
   static CBigNum FromHexString(const char *szIn);
   static CBigNum FromBase64String(const char *szIn);

   bool operator<(const CBigNum &rhs) const;
   bool operator<=(const CBigNum &rhs) const;
   bool operator==(const CBigNum &rhs) const;
   bool operator!=(const CBigNum &rhs) const;
   bool operator>(const CBigNum &rhs) const;
   bool operator>=(const CBigNum &rhs) const;

   bool operator<(const unsigned int rhs) const;
   bool operator<=(const unsigned int rhs) const;
   bool operator==(const unsigned int rhs) const;
   bool operator!=(const unsigned int rhs) const;
   bool operator>(const unsigned int rhs) const;
   bool operator>=(const unsigned int rhs) const;

   operator bool() const;

   operator CBigNumString() const;
   operator const char *() const;

   CBigNumString ToByteString(bool bMakePrintable = true) const;
   CBigNumString ToHexString() const;
   //CBigNumString ToBase64String() const;

   static const char szBase64[];

private:
	void HandleCarry();
	unsigned int m_nSize;
	unsigned int * m_arVal;
};