Esempi in C++ (Cpp) per Poly2Mod

Esempio n. 1

File: poly2mod.cpp Progetto: CodeMason/skype_part3_source

void reduce(const Poly2& p,Poly2Mod& rem)
{
    int m,d;
    GF2m t;
    big *G;
    term2 *ptr,*pos=NULL;
    int n=degree(p);
    int degm=degree(Modulus);

    if (n-degm < KARAT_BREAK_EVEN)
    {
        rem=(Poly2Mod)p;
        return;
    }

    G=(big *)mr_alloc(2*(N+2),sizeof(big));
    
    ptr=p.start;
    while (ptr!=NULL)
    {
        G[ptr->n]=getbig(ptr->an);
        ptr=ptr->next;
    }

    karmul2_poly(N,T,GRF,&G[N],W);   // W=(G/x^n) * h

    for (d=N-1;d<2*N;d++) copy(W[d],Q[d-N+1]);
    m=N+1; if(m%2==1) m=N+2;   // make sure m is even - pad if necessary

    for (d=m;d<2*m;d++) copy(G[d],W[d]);
   
    karmul2_poly_upper(m,T,GF,Q,W);

    pos=NULL;
    rem.clear();
    for (d=N-1;d>=0;d--)
    {
        add2(W[d],G[d],W[d]);
        t=W[d];
        if (t.iszero()) continue;
        pos=rem.addterm(t,d,pos);
    }
    
    mr_free(G);
}

Esempio n. 2

File: schoof2.cpp Progetto: BingyZhang/CommutEnc

void elliptic_add(Poly2Mod& XT,Poly2Mod& XTy,Poly2Mod& YT,Poly2Mod& YTy,Poly2Mod& ZT,Poly2Mod& X,Poly2Mod& Y,Poly2Mod& Yy)
{ // add (X,Y,Z) to (XT,YT,ZT) on an elliptic curve 
  // The point Y is of the form A(x)+B(x).y

    Poly2Mod ZT2,ZT3,W1,W2,W3,W4,W5,W5y,W6,W6y,W7,W8,W8y,W9,W9y;

    ZT2=(ZT*ZT);

    W3=XT+X*ZT2;

    ZT3=ZT2*ZT;
    W5=ZT3*Y;
    W5y=ZT3*Yy;

    W6=YT+W5;
    W6y=YTy+W5y;

    if (iszero(W3))
    {
        if (iszero(W6) && iszero(W6y))
        { // should have doubled!
            elliptic_dup(XT,YT,YTy,ZT);
            XTy=0;
            return;
        }

        ZT.clear();
        return;
    }


    ZT*=W3;

    W8=W6*X+ZT*Y;
    W8y=W6y*X+ZT*Yy;

    W9=W6+ZT;

    W1=ZT*ZT;
    W2=W6y*W6y;
    
    XT=A*W1+W3*W3*W3+W6*W9+W2*MFX;
    XTy=W9*W6y+W6y*W6+W2*XX;

    W2=W6y*XTy;

    YT=W9*XT+W2*MFX+W8*W1;
    YTy=XT*W6y+W9*XTy+W2*XX+W1*W8y;
}