www.pudn.com > miracl.zip > MONTY.H

/* 
 *    MIRACL  C++ Header file monty.h 
 * 
 *    AUTHOR  : M. Scott 
 *   
 *    PURPOSE : Definition of class ZZn  (Arithmetic mod n), using  
 *              Montgomery's Method for modular multiplication 
 *    NOTE    : Must be used in conjunction with big.cpp and monty.cpp 
 *              The modulus n is always set dynamically (via the modulo()  
 *              routine) - so beware the pitfalls implicit in declaring 
 *              static or global ZZn's (which are initialised before n is  
 *              set!). Uninitialised data is OK  
 *                 
 *    Copyright (c) 1988-2001 Shamus Software Ltd. 
 */ 
 
#ifndef MONTY_H 
#define MONTY_H 
 
#include  
 
class ZZn  
{  
    Big fn; 
public: 
    ZZn()       {  }  
    ZZn(int i)  { if (i==0) fn=0; else fn=nres((Big)i); } 
    ZZn(long lg){ if (lg==0L) fn=0; else fn=nres((Big)lg); } 
    ZZn(const Big& b) { fn=nres(b); }   /* Big -> ZZn */ 
    ZZn(big& b)        {copy(b,fn.getbig());} 
    ZZn(const ZZn& b) { fn=b.fn; } 
    ZZn(char* s){ fn=nres((Big)s); } 
 
    ZZn& operator=(int i) {if (i==0) fn=0; else fn=nres((Big)i); return *this;} 
    ZZn& operator=(long lg) 
                      {if (lg==0L) fn=0; else fn=nres((Big)lg); return *this;} 
    ZZn& operator=(const ZZn& b){fn=b.fn; return *this;} 
    ZZn& operator=(char* s){fn=nres((Big)s); return *this;} 
    ZZn& operator=(big b) {copy(b,fn.getbig()); return *this; } 
 
/* Use fast in-line code */ 
 
    ZZn& operator++()  
        {nres_modadd(fn,nres((Big)1),fn);return *this;} 
    ZZn& operator--()  
        {nres_modsub(fn,nres((Big)1),fn);return *this;} 
    ZZn& operator+=(int i)  
        {nres_modadd(fn,nres((Big)i),fn);return *this;} 
    ZZn& operator-=(int i)  
        {nres_modsub(fn,nres((Big)i),fn); return *this;} 
    ZZn& operator+=(const ZZn& b)  
        {nres_modadd(fn,b.fn,fn); return *this;} 
    ZZn& operator-=(const ZZn& b)  
        {nres_modsub(fn,b.fn,fn); return *this;} 
    ZZn& operator*=(const ZZn& b)  
        {nres_modmult(fn,b.fn,fn); return *this;} 
    ZZn& operator*=(int i)  
        {nres_premult(fn,i,fn); return *this;} 
 
    BOOL iszero() const; 
    BOOL isminusone() const; 
 
    operator Big() {return redc(fn);}   /* ZZn -> Big */ 
    friend big getbig(ZZn& z) {return z.fn.getbig();} 
 
    ZZn& operator/=(const ZZn& b) {nres_moddiv(fn,b.fn,fn); return *this;} 
    ZZn& operator/=(int i) {nres_moddiv(fn,nres((Big)i),fn);return *this;} 
 
    friend ZZn operator-(const ZZn&); 
    friend ZZn operator+(const ZZn&,int); 
    friend ZZn operator+(int, const ZZn&); 
    friend ZZn operator+(const ZZn&, const ZZn&); 
 
    friend ZZn operator-(const ZZn&, int); 
    friend ZZn operator-(int, const ZZn&); 
    friend ZZn operator-(const ZZn&, const ZZn&); 
 
    friend ZZn operator*(const ZZn&,int); 
    friend ZZn operator*(int, const ZZn&); 
    friend ZZn operator*(const ZZn&, const ZZn&); 
 
    friend ZZn operator/(const ZZn&, int); 
    friend ZZn operator/(int, const ZZn&); 
    friend ZZn operator/(const ZZn&, const ZZn&); 
 
    friend BOOL operator==(const ZZn& b1,const ZZn& b2) 
    { if (b1.fn==b2.fn) return TRUE; else return FALSE;} 
    friend BOOL operator!=(const ZZn& b1,const ZZn& b2) 
    { if (b1.fn!=b2.fn) return TRUE; else return FALSE;} 
 
    friend ZZn  pow( const ZZn&, const Big&); 
    friend ZZn  pow( const ZZn&,int); 
    friend ZZn  pow( const ZZn&, const Big&, const ZZn&, const Big&); 
    friend ZZn  pow( int,ZZn *,Big *);     
 
    friend ZZn  randn(void);      // random number < modulus 
    friend BOOL qr(ZZn&);   // test for quadratic residue 
    friend BOOL qnr(ZZn&);  // test for quadratic non-residue 
    friend ZZn getA(void);        // get A parameter of elliptic curve 
    friend ZZn getB(void);        // get B parameter of elliptic curve 
 
    friend ZZn  sqrt(const ZZn&);          // only works if modulus is prime 
    friend ZZn  luc( const ZZn&, const Big&, ZZn* b3=NULL); 
    ~ZZn() { } 
}; 
 
#endif