/* Create random BIG in portable way, one bit at a time */
public static BIG RandomNum(BIG q, RAND rng)
{
DBIG d = new DBIG(0);
int i, b, j = 0, r = 0;
for (i = 0; i < 2 * q.NBits(); i++)
{
if (j == 0)
{
r = rng.Byte;
}
else
{
r >>= 1;
}
b = r & 1;
d.Shl(1);
d.w[0] += b; // m.inc(b);
j++;
j &= 7;
}
BIG m = d.Mod(q);
return(m);
}
/* return a^2 mod m */
public static BIG ModSqr(BIG a1, BIG m)
{
BIG a = new BIG(a1);
a.Mod(m);
DBIG d = Sqr(a);
return(d.Mod(m));
}
/* return a*b mod m */
public static BIG ModMul(BIG a1, BIG b1, BIG m)
{
BIG a = new BIG(a1);
BIG b = new BIG(b1);
a.Mod(m);
b.Mod(m);
DBIG d = Mul(a, b);
return(d.Mod(m));
}