mrcurve.c

miracl-大数运算库,大家使用有什么问题请多多提意见

#ifndef MR_AFFINE_ONLY
    if (mr_mip->coord==MR_AFFINE)
    {
#endif
        if (compare(a->X,b->X)==0 && compare(a->Y,b->Y)==0) result=TRUE;
        else result=FALSE;
        return result;
#ifndef MR_AFFINE_ONLY
    }

    if (mr_mip->coord==MR_PROJECTIVE)
    {
        MR_IN(105)
        if (a->marker!=MR_EPOINT_GENERAL) 
        {
            convert(_MIPP_ 1,mr_mip->w1);
            nres(_MIPP_ mr_mip->w1,mr_mip->w1);
        }
        else copy(a->Z,mr_mip->w1);

        if (b->marker!=MR_EPOINT_GENERAL) 
        {
            convert(_MIPP_ 1,mr_mip->w2);
            nres(_MIPP_ mr_mip->w2,mr_mip->w2);
        }
        else copy(b->Z,mr_mip->w2);

        nres_modmult(_MIPP_ mr_mip->w1,mr_mip->w1,mr_mip->w3); /* Za*Za */
        nres_modmult(_MIPP_ mr_mip->w2,mr_mip->w2,mr_mip->w4); /* Zb*Zb */

        nres_modmult(_MIPP_ a->X,mr_mip->w4,mr_mip->w5); /* Xa*Zb*Zb */
        nres_modmult(_MIPP_ b->X,mr_mip->w3,mr_mip->w6); /* Xb*Za*Za */

        if (compare(mr_mip->w5,mr_mip->w6)!=0) result=FALSE;
        else
        {
            nres_modmult(_MIPP_ mr_mip->w1,mr_mip->w3,mr_mip->w3);
            nres_modmult(_MIPP_ mr_mip->w2,mr_mip->w4,mr_mip->w4);

            nres_modmult(_MIPP_ a->Y,mr_mip->w4,mr_mip->w5);
            nres_modmult(_MIPP_ b->Y,mr_mip->w3,mr_mip->w6);

            if (compare(mr_mip->w5,mr_mip->w6)!=0) result=FALSE;
            else result=TRUE;
        }
        MR_OUT
        return result;
    }
    return FALSE;
#endif
}

big ecurve_add(_MIPD_ epoint *p,epoint *pa)
{  /* pa=pa+p; */
   /* An ephemeral pointer to the line slope is returned */

#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return NULL;

    MR_IN(94)

    if (p==pa) 
    {
        ecurve_double(_MIPP_ pa);
        MR_OUT
        if (pa->marker==MR_EPOINT_INFINITY) return NULL;
        return mr_mip->w8;
    }
    if (pa->marker==MR_EPOINT_INFINITY)
    {
        epoint_copy(p,pa);
        MR_OUT 
        return NULL;
    }
    if (p->marker==MR_EPOINT_INFINITY) 
    {
        MR_OUT
        return NULL;
    }

    if (!ecurve_padd(_MIPP_ p,pa)) ecurve_double(_MIPP_ pa);
    MR_OUT

    if (pa->marker==MR_EPOINT_INFINITY) return NULL;
    return mr_mip->w8;
}

void epoint_negate(_MIPD_ epoint *p)
{ /* negate a point */
#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return;
    if (p->marker==MR_EPOINT_INFINITY) return;

    MR_IN(121)
    if (size(p->Y)!=0) mr_psub(_MIPP_ mr_mip->modulus,p->Y,p->Y);
    MR_OUT
}

big ecurve_sub(_MIPD_ epoint *p,epoint *pa)
{
    big r;
#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return NULL;

    MR_IN(104)

    if (p==pa)
    {
        epoint_set(_MIPP_ NULL,NULL,0,pa);
        MR_OUT
        return NULL;
    } 
    if (p->marker==MR_EPOINT_INFINITY) 
    {
        MR_OUT
        return NULL;
    }

    epoint_negate(_MIPP_ p);
    r=ecurve_add(_MIPP_ p,pa);
    epoint_negate(_MIPP_ p);

    MR_OUT
    return r;
}

void ecurve_mult(_MIPD_ big e,epoint *pa,epoint *pt)
{ /* pt=e*pa; */
    int i,j,n,nb,nbs,nzs;
    epoint *p;
    epoint *table[11];

#ifdef MR_STATIC
    char mem[MR_ECP_RESERVE(12)];  
#else
    char *mem;
#endif

#ifndef MR_ALWAYS_BINARY
    int ce,ch;
#endif
#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return;

    MR_IN(95)

    if (size(e)==0) 
    { /* multiplied by 0 */
        epoint_set(_MIPP_ NULL,NULL,0,pt);
        MR_OUT
        return;
    }
    copy(e,mr_mip->w9);
    epoint_norm(_MIPP_ pa);
    epoint_copy(pa,pt);

    if (size(mr_mip->w9)<0)
    { /* pt = -pt */
        negify(mr_mip->w9,mr_mip->w9);
        epoint_negate(_MIPP_ pt);
    }

    if (size(mr_mip->w9)==1)
    { 
        MR_OUT
        return;
    }

    premult(_MIPP_ mr_mip->w9,3,mr_mip->w10);      /* h=3*e */

#ifndef MR_ALWAYS_BINARY
    if (mr_mip->base==mr_mip->base2)
    {
#endif

#ifdef  MR_STATIC
        memset(mem,0,MR_ECP_RESERVE(12));
#else
        mem=ecp_memalloc(_MIPP_ 12);
#endif
        p=epoint_init_mem(_MIPP_ mem,0);
        epoint_copy(pt,p);

        table[0]=epoint_init_mem(_MIPP_ mem,1);

        epoint_copy(p,table[0]);
        ecurve_double(_MIPP_ p);

        for (i=1;i<=10;i++)
        { /* precomputation */
            table[i]=epoint_init_mem(_MIPP_ mem,i+1);
            epoint_copy(table[i-1],table[i]);
            ecurve_add(_MIPP_ p,table[i]);
        }

  /* note that normalising this table doesn't really help */
        nb=logb2(_MIPP_ mr_mip->w10);

        for (i=nb-2;i>=1;)
        { /* add/subtract */
            if (mr_mip->user!=NULL) (*mr_mip->user)();
            n=mr_naf_window(_MIPP_ mr_mip->w9,mr_mip->w10,i,&nbs,&nzs);
            for (j=0;j<nbs;j++)
                ecurve_double(_MIPP_ pt);
            if (n>0) ecurve_add(_MIPP_ table[n/2],pt);
            if (n<0) ecurve_sub(_MIPP_ table[(-n)/2],pt);
            i-=nbs;
            if (nzs)
            {
                for (j=0;j<nzs;j++) ecurve_double(_MIPP_ pt);
                i-=nzs;
            }
        }
        ecp_memkill(_MIPP_ mem,12);

#ifndef MR_ALWAYS_BINARY
    }
    else
    { 
        mem=ecp_memalloc(_MIPP_ 1);
        p=epoint_init_mem(_MIPP_ mem,0);
        epoint_copy(pt,p);

        expb2(_MIPP_ logb2(_MIPP_ mr_mip->w10)-1,mr_mip->w11);
        mr_psub(_MIPP_ mr_mip->w10,mr_mip->w11,mr_mip->w10);
        subdiv(_MIPP_ mr_mip->w11,2,mr_mip->w11);
        while (size(mr_mip->w11) > 1)
        { /* add/subtract method */
            if (mr_mip->user!=NULL) (*mr_mip->user)();

            ecurve_double(_MIPP_ pt);
            ce=compare(mr_mip->w9,mr_mip->w11); /* e(i)=1? */
            ch=compare(mr_mip->w10,mr_mip->w11); /* h(i)=1? */
            if (ch>=0) 
            {  /* h(i)=1 */
                if (ce<0) ecurve_add(_MIPP_ p,pt);
                mr_psub(_MIPP_ mr_mip->w10,mr_mip->w11,mr_mip->w10);
            }
            if (ce>=0) 
            {  /* e(i)=1 */
                if (ch<0) ecurve_sub(_MIPP_ p,pt);
                mr_psub(_MIPP_ mr_mip->w9,mr_mip->w11,mr_mip->w9);  
            }
            subdiv(_MIPP_ mr_mip->w11,2,mr_mip->w11);
        }
        ecp_memkill(_MIPP_ mem,1);
    }
#endif
    MR_OUT
}

#ifndef MR_STATIC

void ecurve_multn(_MIPD_ int n,big *y,epoint **x,epoint *w)
{ /* pt=e[o]*p[0]+e[1]*p[1]+ .... e[n-1]*p[n-1]   */
    int i,j,k,m,nb,ea;
    epoint **G;
#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return;

    MR_IN(114)

    m=1<<n;
    G=(epoint **)mr_alloc(_MIPP_ m,sizeof(epoint*));

    for (i=0,k=1;i<n;i++)
    {
        for (j=0; j < (1<<i) ;j++)
        {
            G[k]=epoint_init(_MIPPO_ );
            epoint_copy(x[i],G[k]);
            if (j!=0) ecurve_add(_MIPP_ G[j],G[k]);
            k++;
        }
    }

    nb=0;
    for (j=0;j<n;j++) if ((k=logb2(_MIPP_ y[j])) > nb) nb=k;

    epoint_set(_MIPP_ NULL,NULL,0,w);            /* w=0 */
    
#ifndef MR_ALWAYS_BINARY
    if (mr_mip->base==mr_mip->base2)
    {
#endif
        for (i=nb-1;i>=0;i--)
        {
            if (mr_mip->user!=NULL) (*mr_mip->user)();
            ea=0;
            k=1;
            for (j=0;j<n;j++)
            {
                if (mr_testbit(_MIPP_ y[j],i)) ea+=k;
                k<<=1;
            }
            ecurve_double(_MIPP_ w);
            if (ea!=0) ecurve_add(_MIPP_ G[ea],w);
        }    
#ifndef MR_ALWAYS_BINARY
    }
    else mr_berror(_MIPP_ MR_ERR_NOT_SUPPORTED);
#endif

    for (i=1;i<m;i++) epoint_free(G[i]);
    mr_free(G);
    MR_OUT
}

#endif

void ecurve_mult2(_MIPD_ big e,epoint *p,big ea,epoint *pa,epoint *pt)
{ /* pt=e*p+ea*pa; */
    int e1,h1,e2,h2;
    epoint *p1,*p2,*ps,*pd;
#ifdef MR_STATIC
    char mem[MR_ECP_RESERVE(4)];
#else
    char *mem;
#endif
#ifdef MR_OS_THREADS
    miracl *mr_mip=get_mip();
#endif
    if (mr_mip->ERNUM) return;

    MR_IN(103)

    if (size(e)==0) 
    {
        ecurve_mult(_MIPP_ ea,pa,pt);
        MR_OUT
        return;
    }
#ifdef MR_STATIC
    memset(mem,0,MR_ECP_RESERVE(4));
#else
    mem=ecp_memalloc(_MIPP_ 4);
#endif
    p2=epoint_init_mem(_MIPP_ mem,0);
    p1=epoint_init_mem(_MIPP_ mem,1);
    ps=epoint_init_mem(_MIPP_ mem,2);
    pd=epoint_init_mem(_MIPP_ mem,3);

    epoint_norm(_MIPP_ pa);
    epoint_copy(pa,p2);
    copy(ea,mr_mip->w9);
    if (size(mr_mip->w9)<0)
    { /* p2 = -p2 */
        negify(mr_mip->w9,mr_mip->w9);
        epoint_negate(_MIPP_ p2);
    }
    premult(_MIPP_ mr_mip->w9,3,mr_mip->w10);      /* 3*ea */

    epoint_norm(_MIPP_ p);
    epoint_copy(p,p1);
    copy(e,mr_mip->w12);
    if (size(mr_mip->w12)<0)
    { /* p1= -p1 */
        negify(mr_mip->w12,mr_mip->w12);
        epoint_negate(_MIPP_ p1);
    }
    premult(_MIPP_ mr_mip->w12,3,mr_mip->w13);    /* 3*e */

    epoint_set(_MIPP_ NULL,NULL,0,pt);            /* pt=0 */

    if (compare(mr_mip->w10,mr_mip->w13)>=0)
         expb2(_MIPP_ logb2(_MIPP_ mr_mip->w10)-1,mr_mip->w11);
    else expb2(_MIPP_ logb2(_MIPP_ mr_mip->w13)-1,mr_mip->w11);

    epoint_copy(p1,ps);
    ecurve_add(_MIPP_ p2,ps);                    /* ps=p1+p2 */
    epoint_copy(p1,pd);
    ecurve_sub(_MIPP_ p2,pd);                    /* pd=p1-p2 */
    epoint_norm(_MIPP_ ps);
    epoint_norm(_MIPP_ pd);
    while (size(mr_mip->w11) > 1)
    { /* add/subtract method */
        if (mr_mip->user!=NULL) (*mr_mip->user)();

        ecurve_double(_MIPP_ pt);

        e1=h1=e2=h2=0;
        if (compare(mr_mip->w9,mr_mip->w11)>=0)
        { /* e1(i)=1? */
            e2=1;  
            mr_psub(_MIPP_ mr_mip->w9,mr_mip->w11,mr_mip->w9);
        }
        if (compare(mr_mip->w10,mr_mip->w11)>=0)
        { /* h1(i)=1? */
            h2=1;  
            mr_psub(_MIPP_ mr_mip->w10,mr_mip->w11,mr_mip->w10);
        } 
        if (compare(mr_mip->w12,mr_mip->w11)>=0)
        { /* e2(i)=1? */
            e1=1;   
            mr_psub(_MIPP_ mr_mip->w12,mr_mip->w11,mr_mip->w12);
        }
        if (compare(mr_mip->w13,mr_mip->w11)>=0) 
        { /* h2(i)=1? */
            h1=1;  
            mr_psub(_MIPP_ mr_mip->w13,mr_mip->w11,mr_mip->w13);
        }

        if (e1!=h1)
        {
            if (e2==h2)
            {
                if (h1==1) ecurve_add(_MIPP_ p1,pt);
                else       ecurve_sub(_MIPP_ p1,pt);
            }
            else
            {
                if (h1==1)
                {
                    if (h2==1) ecurve_add(_MIPP_ ps,pt);
                    else       ecurve_add(_MIPP_ pd,pt);
                }
                else
                {
                    if (h2==1) ecurve_sub(_MIPP_ pd,pt);
                    else       ecurve_sub(_MIPP_ ps,pt);
                }
            }
        }
        else if (e2!=h2)
        {
            if (h2==1) ecurve_add(_MIPP_ p2,pt);
            else       ecurve_sub(_MIPP_ p2,pt);
        }

        subdiv(_MIPP_ mr_mip->w11,2,mr_mip->w11);
    }
    ecp_memkill(_MIPP_ mem,4);
    MR_OUT
}