public BIG(DBIG x)
{
for (int i = 0; i < NLEN; i++)
{
w[i] = x.w[i];
}
}
/* 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 as DBIG */
/* Input must be normed */
public static DBIG Sqr(BIG a)
{
DBIG c = new DBIG(0);
long carry;
long[] cr = new long[2];
for (int i = 0; i < NLEN; i++)
{
carry = 0;
for (int j = i + 1; j < NLEN; j++)
{
cr = MulAdd(2 * a.w[i], a.w[j], carry, c.w[i + j]);
carry = cr[0];
c.w[i + j] = cr[1];
}
c.w[NLEN + i] = carry;
}
for (int i = 0; i < NLEN; i++)
{
cr = MulAdd(a.w[i], a.w[i], 0, c.w[2 * i]);
c.w[2 * i + 1] += cr[0];
c.w[2 * i] = cr[1];
}
c.Norm();
return(c);
}
public virtual void Copy(DBIG x)
{
for (int i = 0; i < NLEN; i++)
{
w[i] = x.w[i];
}
}
/* 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));
}
/* return this*c and catch overflow in DBIG */
public virtual DBIG PXMul(int c)
{
DBIG m = new DBIG(0);
long[] cr;
long carry = 0;
for (int j = 0; j < NLEN; j++)
{
cr = MulAdd(w[j], (long)c, carry, m.w[j]);
carry = cr[0];
m.w[j] = cr[1];
}
m.w[NLEN] = carry;
return(m);
}
internal static BIG Monty(BIG md, long MC, DBIG d)
{
BIG b;
long m, carry;
long[] cr = new long[2];
for (int i = 0; i < NLEN; i++)
{
if (MC == -1)
{
m = -d.w[i] & BMASK;
}
else
{
if (MC == 1)
{
m = d.w[i];
}
else
{
m = (MC * d.w[i]) & BMASK;
}
}
carry = 0;
for (int j = 0; j < NLEN; j++)
{
cr = MulAdd(m, md.w[j], carry, d.w[i + j]);
carry = cr[0];
d.w[i + j] = cr[1];
}
d.w[NLEN + i] += carry;
}
b = new BIG(0);
for (int i = 0; i < NLEN; i++)
{
b.w[i] = d.w[NLEN + i];
}
b.Norm();
return(b);
}
/* return a*b as DBIG */
/* Inputs must be normed */
public static DBIG Mul(BIG a, BIG b)
{
DBIG c = new DBIG(0);
long carry;
long[] cr = new long[2];
for (int i = 0; i < NLEN; i++)
{
carry = 0;
for (int j = 0; j < NLEN; j++)
{
cr = MulAdd(a.w[i], b.w[j], carry, c.w[i + j]);
carry = cr[0];
c.w[i + j] = cr[1];
}
c.w[NLEN + i] = carry;
}
return(c);
}
