static void
powermodg(
giant x,
giant n,
curveParams *cp
)
/* x becomes x^n (mod basePrime). */
{
int len, pos;
giant scratch2 = borrowGiant(cp->maxDigits);
gtog(x, scratch2);
int_to_giant(1, x);
len = bitlen(n);
pos = 0;
while (1)
{
if (bitval(n, pos++))
{
mulg(scratch2, x);
feemod(cp, x);
}
if (pos>=len)
break;
gsquare(scratch2);
feemod(cp, scratch2);
}
returnGiant(scratch2);
}
/*
* New, 13 Jan 1997.
*/
static void feepowermodg(curveParams *par, giant x, giant n)
/* Power ladder.
x := x^n (mod 2^q-k)
*/
{
int len, pos;
giant t1;
PROF_START;
t1 = borrowGiant(par->maxDigits);
gtog(x, t1);
int_to_giant(1, x);
len = bitlen(n);
pos = 0;
while(1) {
if(bitval(n, pos++)) {
mulg(t1, x);
feemod(par, x);
}
if(pos>=len) break;
gsquare(t1);
feemod(par, t1);
}
returnGiant(t1);
PROF_END(powerModTime);
}
void ellMulProj(pointProj pt0, pointProj pt1, giant k, curveParams *cp)
/* General elliptic multiplication;
pt1 := k*pt0 on the curve,
with k an arbitrary integer.
*/
{
giant x = pt0->x, y = pt0->y, z = pt0->z,
xx = pt1->x, yy = pt1->y, zz = pt1->z;
int ksign, hlen, klen, b, hb, kb;
giant t0;
CKASSERT(cp->curveType == FCT_Weierstrass);
if(isZero(k)) {
int_to_giant(1, xx);
int_to_giant(1, yy);
int_to_giant(0, zz);
return;
}
t0 = borrowGiant(cp->maxDigits);
ksign = k->sign;
if(ksign < 0) negg(k);
gtog(x,xx); gtog(y,yy); gtog(z,zz);
gtog(k, t0); addg(t0, t0); addg(k, t0); /* t0 := 3k. */
hlen = bitlen(t0);
klen = bitlen(k);
for(b = hlen-2; b > 0; b--) {
ellDoubleProj(pt1,cp);
hb = bitval(t0, b);
if(b < klen) kb = bitval(k, b); else kb = 0;
if((hb != 0) && (kb == 0))
ellAddProj(pt1, pt0, cp);
else if((hb == 0) && (kb !=0))
ellSubProj(pt1, pt0, cp);
}
if(ksign < 0) {
ellNegProj(pt1, cp);
k->sign = -k->sign;
}
returnGiant(t0);
}
//-----------------------------------------------------------------------------
// 將指定旗標設為true
bool C_FlagCtrl::Set(IN unsigned long ulPos)
{
if(m_pData == nullptr)
return false;
if(ulPos >= m_ulSize)
return false;
unsigned long uiPage = ulPos / 8;
unsigned long uiBits = ulPos % 8;
char *pData = (char *)m_pData + uiPage;
*pData = bitval(*pData, static_cast<unsigned char>(uiBits), true);
return true;
}
static void
powFp2(giant a, giant b, giant w2, giant n, curveParams *cp)
/* Perform powering in the field F_p^2:
a + b w := (a + b w)^n (mod p), where parameter w2 is a quadratic
nonresidue (formally equal to w^2).
*/
{
int j;
giant t6;
giant t7;
giant t8;
giant t9;
if(isZero(n)) {
int_to_giant(1,a);
int_to_giant(0,b);
return;
}
t6 = borrowGiant(cp->maxDigits);
t7 = borrowGiant(cp->maxDigits);
t8 = borrowGiant(cp->maxDigits);
t9 = borrowGiant(cp->maxDigits);
gtog(a, t8); gtog(b, t9);
for(j = bitlen(n)-2; j >= 0; j--) {
gtog(b, t6);
mulg(a, b); addg(b,b); feemod(cp, b); /* b := 2 a b. */
gsquare(t6); feemod(cp, t6);
mulg(w2, t6); feemod(cp, t6);
gsquare(a); addg(t6, a); feemod(cp, a);
/* a := a^2 + b^2 w2. */
if(bitval(n, j)) {
gtog(b, t6); mulg(t8, b); feemod(cp, b);
gtog(a, t7); mulg(t9, a); addg(a, b); feemod(cp, b);
mulg(t9, t6); feemod(cp, t6);
mulg(w2, t6); feemod(cp, t6);
mulg(t8, a); addg(t6, a); feemod(cp, a);
}
}
returnGiant(t6);
returnGiant(t7);
returnGiant(t8);
returnGiant(t9);
return;
}
void powermodg(giant x, giant n, giant g)
/* x becomes x^n (mod g). */
{
int len, pos;
giant scratch2 = popg();
gtog(x, scratch2);
itog(1, x);
len = bitlen(n);
pos = 0;
while (1)
{
if (bitval(n, pos++))
{
mulg(scratch2, x);
modg(g, x);
}
if (pos >= len)
break;
squareg(scratch2);
modg(g, scratch2);
}
pushg(1);
}
/*
* General elliptic multiply.
*
* {xx, zz} := k * {xx, zz}
*/
void elliptic(giant xx, giant zz, giant k, curveParams *par) {
int len = bitlen(k);
int pos = len - 2;
giant xs;
giant zs;
giant xorg;
giant zorg;
PROF_START;
if(sequalg(1,k)) return;
if(sequalg(2,k)) {
ell_even(xx, zz, xx, zz, par);
goto out;
}
zs = borrowGiant(par->maxDigits);
xs = borrowGiant(par->maxDigits);
zorg = borrowGiant(par->maxDigits);
xorg = borrowGiant(par->maxDigits);
gtog(xx, xorg); gtog(zz, zorg);
ell_even(xx, zz, xs, zs, par);
do {
if(bitval(k, pos--)) {
ell_odd(xs, zs, xx, zz, xorg, zorg, par);
ell_even(xs, zs, xs, zs, par);
} else {
ell_odd(xx, zz, xs, zs, xorg, zorg, par);
ell_even(xx, zz, xx, zz, par);
}
} while (pos >= 0); // REC fix 9/23/94
returnGiant(xs);
returnGiant(zs);
returnGiant(xorg);
returnGiant(zorg);
out:
PROF_END(ellipticTime);
}
