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/* GENERATED SOURCE. DO NOT MODIFY. */
package com.android.internal.org.bouncycastle.math.ec.custom.sec;
import java.math.BigInteger;
import java.security.SecureRandom;
import com.android.internal.org.bouncycastle.math.ec.AbstractECLookupTable;
import com.android.internal.org.bouncycastle.math.ec.ECConstants;
import com.android.internal.org.bouncycastle.math.ec.ECCurve;
import com.android.internal.org.bouncycastle.math.ec.ECFieldElement;
import com.android.internal.org.bouncycastle.math.ec.ECLookupTable;
import com.android.internal.org.bouncycastle.math.ec.ECPoint;
import com.android.internal.org.bouncycastle.math.raw.Nat256;
import com.android.internal.org.bouncycastle.util.encoders.Hex;
/**
* @hide This class is not part of the Android public SDK API
*/
public class SecP256K1Curve extends ECCurve.AbstractFp
{
public static final BigInteger q = SecP256K1FieldElement.Q;
private static final int SECP256K1_DEFAULT_COORDS = COORD_JACOBIAN;
private static final ECFieldElement[] SECP256K1_AFFINE_ZS = new ECFieldElement[] { new SecP256K1FieldElement(ECConstants.ONE) };
protected SecP256K1Point infinity;
public SecP256K1Curve()
{
super(q);
this.infinity = new SecP256K1Point(this, null, null);
this.a = fromBigInteger(ECConstants.ZERO);
this.b = fromBigInteger(BigInteger.valueOf(7));
this.order = new BigInteger(1, Hex.decodeStrict("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141"));
this.cofactor = BigInteger.valueOf(1);
this.coord = SECP256K1_DEFAULT_COORDS;
}
protected ECCurve cloneCurve()
{
return new SecP256K1Curve();
}
public boolean supportsCoordinateSystem(int coord)
{
switch (coord)
{
case COORD_JACOBIAN:
return true;
default:
return false;
}
}
public BigInteger getQ()
{
return q;
}
public int getFieldSize()
{
return q.bitLength();
}
public ECFieldElement fromBigInteger(BigInteger x)
{
return new SecP256K1FieldElement(x);
}
protected ECPoint createRawPoint(ECFieldElement x, ECFieldElement y)
{
return new SecP256K1Point(this, x, y);
}
protected ECPoint createRawPoint(ECFieldElement x, ECFieldElement y, ECFieldElement[] zs)
{
return new SecP256K1Point(this, x, y, zs);
}
public ECPoint getInfinity()
{
return infinity;
}
public ECLookupTable createCacheSafeLookupTable(ECPoint[] points, int off, final int len)
{
final int FE_INTS = 8;
final int[] table = new int[len * FE_INTS * 2];
{
int pos = 0;
for (int i = 0; i < len; ++i)
{
ECPoint p = points[off + i];
Nat256.copy(((SecP256K1FieldElement)p.getRawXCoord()).x, 0, table, pos); pos += FE_INTS;
Nat256.copy(((SecP256K1FieldElement)p.getRawYCoord()).x, 0, table, pos); pos += FE_INTS;
}
}
return new AbstractECLookupTable()
{
public int getSize()
{
return len;
}
public ECPoint lookup(int index)
{
int[] x = Nat256.create(), y = Nat256.create();
int pos = 0;
for (int i = 0; i < len; ++i)
{
int MASK = ((i ^ index) - 1) >> 31;
for (int j = 0; j < FE_INTS; ++j)
{
x[j] ^= table[pos + j] & MASK;
y[j] ^= table[pos + FE_INTS + j] & MASK;
}
pos += (FE_INTS * 2);
}
return createPoint(x, y);
}
public ECPoint lookupVar(int index)
{
int[] x = Nat256.create(), y = Nat256.create();
int pos = index * FE_INTS * 2;
for (int j = 0; j < FE_INTS; ++j)
{
x[j] = table[pos + j];
y[j] = table[pos + FE_INTS + j];
}
return createPoint(x, y);
}
private ECPoint createPoint(int[] x, int[] y)
{
return createRawPoint(new SecP256K1FieldElement(x), new SecP256K1FieldElement(y), SECP256K1_AFFINE_ZS);
}
};
}
public ECFieldElement randomFieldElement(SecureRandom r)
{
int[] x = Nat256.create();
SecP256K1Field.random(r, x);
return new SecP256K1FieldElement(x);
}
public ECFieldElement randomFieldElementMult(SecureRandom r)
{
int[] x = Nat256.create();
SecP256K1Field.randomMult(r, x);
return new SecP256K1FieldElement(x);
}
}
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