/// <summary>
/// Modulus.
/// </summary>
/// <param name="mod">Modulus.</param>
public void Mod(GXBigInteger mod)
{
/*
* //value = value - (mod * (value / mod) )
* GXBigInteger tmp = new GXBigInteger(this);
* tmp.Div(mod);
* tmp.Multiply(mod);
* Sub(tmp);
* changed = true;
*/
GXBigInteger current = new GXBigInteger(1);
GXBigInteger denom = new GXBigInteger(mod);
bool neq = negative;
negative = false;
// while denom < this.
while (denom.Compare(this) == -1)
{
current.Lshift(1);
denom.Lshift(1);
}
//If overflow.
if (denom.Compare(this) == 1)
{
if (current.IsOne)
{
if (neq)
{
Sub(mod);
negative = false;
}
return;
}
current.Rshift(1);
denom.Rshift(1);
while (!current.IsZero)
{
int r = Compare(denom);
if (r == 1)
{
Sub(denom);
}
else if (r == 0)
{
break;
}
current.Rshift(1);
denom.Rshift(1);
}
}
else
{
Clear();
}
if (neq)
{
Sub(mod);
negative = false;
}
}
public void Div(GXBigInteger value)
{
GXBigInteger current = new GXBigInteger(1);
GXBigInteger denom = new GXBigInteger(value);
GXBigInteger tmp = new GXBigInteger(this);
bool neq = negative;
negative = false;
try
{
// while denom < this.
while (denom.Compare(this) == -1)
{
current.Lshift(1);
denom.Lshift(1);
}
//If overflow.
if (denom.Compare(this) == 1)
{
if (current.IsOne)
{
Clear();
return;
}
Clear();
current.Rshift(1);
denom.Rshift(1);
while (!current.IsZero)
{
int r = tmp.Compare(denom);
if (r == 1)
{
tmp.Sub(denom);
Add(current);
}
else if (r == 0)
{
Add(current);
break;
}
current.Rshift(1);
denom.Rshift(1);
}
current.Data = Data;
}
}
finally
{
negative = neq;
}
Data = current.Data;
changed = true;
}
/// <summary>
/// Multily elliptic curve point and scalar.
/// </summary>
/// <remarks>
/// Y^2 = X^3 + A*X + B (mod p)
/// </remarks>
/// <param name="eccSize"></param>
/// <param name="p">Point to multiply</param>
/// <param name="n">Scalar to multiply</param>
/// <param name="N">Elliptic curve order.</param>
/// <param name="A"></param>
/// <param name="P">Prime number</param>
internal static GXEccPoint JacobianMultiply(GXEccPoint p, GXBigInteger n, GXBigInteger N, GXBigInteger A, GXBigInteger P)
{
GXBigInteger tmp;
if (p.y.IsZero || n.IsZero)
{
return(new GXEccPoint(0, 0, 1));
}
if (n.IsOne)
{
return(p);
}
if (n.Compare(0) == -1 || n.Compare(N) != -1)
{
tmp = new GXBigInteger(n);
tmp.Mod(N);
return(JacobianMultiply(p, tmp, N, A, P));
}
if (n.IsEven)
{
tmp = new GXBigInteger(n);
tmp.Rshift(1);
return(JacobianDouble(JacobianMultiply(p, tmp, N, A, P), A, P));
}
tmp = new GXBigInteger(n);
tmp.Rshift(1);
GXEccPoint p2 = JacobianDouble(JacobianMultiply(p, tmp, N, A, P), A, P);
JacobianAdd(p2, p, A, P);
return(p2);
}
/// <summary>
/// Modulus.
/// </summary>
/// <param name="mod">Modulus.</param>
public void Mod(GXBigInteger mod)
{
GXBigInteger current = new GXBigInteger(1);
GXBigInteger denom = new GXBigInteger(mod);
//Shift UInt32 values to make this faster.
if (denom.Count < Count - 1)
{
UInt32[] tmp = new UInt32[Count - denom.Count - 1];
//Append UInt32 values.
current.InsertRange(0, tmp);
denom.InsertRange(0, tmp);
current.changed = denom.changed = true;
}
bool neq = negative;
negative = false;
// while denom < this.
while (denom.Compare(this) == -1)
{
current.Lshift(1);
denom.Lshift(1);
}
//If overflow.
if (denom.Compare(this) == 1)
{
if (current.IsOne)
{
if (neq)
{
Sub(mod);
negative = false;
}
return;
}
current.Rshift(1);
denom.Rshift(1);
while (!current.IsZero)
{
int r = Compare(denom);
if (r == 1)
{
Sub(denom);
}
else if (r == 0)
{
break;
}
current.Rshift(1);
denom.Rshift(1);
}
}
else
{
Clear();
}
if (neq)
{
Sub(mod);
negative = false;
}
changed = true;
}
public void Div(GXBigInteger value)
{
GXBigInteger current = new GXBigInteger(1);
GXBigInteger denom = new GXBigInteger(value);
GXBigInteger tmp = new GXBigInteger(this);
bool neq = negative;
negative = false;
try
{
//Shift UInt32 values to make this faster.
if (denom.Count < Count - 1)
{
UInt32[] tmp2 = new UInt32[Count - denom.Count - 1];
//Append UInt32 values.
current.InsertRange(0, tmp2);
denom.InsertRange(0, tmp2);
current.changed = denom.changed = true;
}
// while denom < this.
while (denom.Compare(this) == -1)
{
current.Lshift(1);
denom.Lshift(1);
}
//If overflow.
if (denom.Compare(this) == 1)
{
if (current.IsOne)
{
Clear();
return;
}
Clear();
current.Rshift(1);
denom.Rshift(1);
while (!current.IsZero)
{
int r = tmp.Compare(denom);
if (r == 1)
{
tmp.Sub(denom);
Add(current);
}
else if (r == 0)
{
Add(current);
break;
}
current.Rshift(1);
denom.Rshift(1);
}
current.Data = Data;
}
}
finally
{
negative = neq;
}
Data = current.Data;
changed = true;
}