initial addition of essential crypto, encoders, workflows and LLM instructions

pkg/crypto/ec/curve.go

@@ -0,0 +1,111 @@
+// Copyright (c) 2015-2021 The btcsuite developers
+// Copyright (c) 2015-2021 The Decred developers
+
+package btcec
+
+import (
+	"fmt"
+
+	"next.orly.dev/pkg/crypto/ec/secp256k1"
+)
+
+// JacobianPoint is an element of the group formed by the secp256k1 curve in
+// Jacobian projective coordinates and thus represents a point on the curve.
+type JacobianPoint = secp256k1.JacobianPoint
+
+// infinityPoint is the jacobian representation of the point at infinity.
+var infinityPoint JacobianPoint
+
+// MakeJacobianPoint returns a Jacobian point with the provided X, Y, and Z
+// coordinates.
+func MakeJacobianPoint(x, y, z *FieldVal) JacobianPoint {
+	return secp256k1.MakeJacobianPoint(x, y, z)
+}
+
+// AddNonConst adds the passed Jacobian points together and stores the result
+// in the provided result param in *non-constant* time.
+func AddNonConst(p1, p2, result *JacobianPoint) {
+	secp256k1.AddNonConst(p1, p2, result)
+}
+
+// DecompressY attempts to calculate the Y coordinate for the given X
+// coordinate such that the result pair is a point on the secp256k1 curve. It
+// adjusts Y based on the desired oddness and returns whether or not it was
+// successful since not all X coordinates are valid.
+//
+// The magnitude of the provided X coordinate field val must be a max of 8 for
+// a correct result. The resulting Y field val will have a max magnitude of 2.
+func DecompressY(x *FieldVal, odd bool, resultY *FieldVal) bool {
+	return secp256k1.DecompressY(x, odd, resultY)
+}
+
+// DoubleNonConst doubles the passed Jacobian point and stores the result in
+// the provided result parameter in *non-constant* time.
+//
+// NOTE: The point must be normalized for this function to return the correct
+// result. The resulting point will be normalized.
+func DoubleNonConst(p, result *JacobianPoint) {
+	secp256k1.DoubleNonConst(p, result)
+}
+
+// ScalarBaseMultNonConst multiplies k*G where G is the base point of the group
+// and k is a big endian integer. The result is stored in Jacobian coordinates
+// (x1, y1, z1).
+//
+// NOTE: The resulting point will be normalized.
+func ScalarBaseMultNonConst(k *ModNScalar, result *JacobianPoint) {
+	secp256k1.ScalarBaseMultNonConst(k, result)
+}
+
+// ScalarMultNonConst multiplies k*P where k is a big endian integer modulo the
+// curve order and P is a point in Jacobian projective coordinates and stores
+// the result in the provided Jacobian point.
+//
+// NOTE: The point must be normalized for this function to return the correct
+// result. The resulting point will be normalized.
+func ScalarMultNonConst(k *ModNScalar, point, result *JacobianPoint) {
+	secp256k1.ScalarMultNonConst(k, point, result)
+}
+
+// ParseJacobian parses a byte slice point as a secp256k1.Publickey and returns the
+// pubkey as a JacobianPoint. If the nonce is a zero slice, the infinityPoint
+// is returned.
+func ParseJacobian(point []byte) (JacobianPoint, error) {
+	var result JacobianPoint
+	if len(point) != 33 {
+		str := fmt.Sprintf(
+			"invalid nonce: invalid length: %v",
+			len(point),
+		)
+		return JacobianPoint{}, makeError(secp256k1.ErrPubKeyInvalidLen, str)
+	}
+	if point[0] == 0x00 {
+		return infinityPoint, nil
+	}
+	noncePk, err := secp256k1.ParsePubKey(point)
+	if err != nil {
+		return JacobianPoint{}, err
+	}
+	noncePk.AsJacobian(&result)
+	return result, nil
+}
+
+// JacobianToByteSlice converts the passed JacobianPoint to a Pubkey
+// and serializes that to a byte slice. If the JacobianPoint is the infinity
+// point, a zero slice is returned.
+func JacobianToByteSlice(point JacobianPoint) []byte {
+	if point.X == infinityPoint.X && point.Y == infinityPoint.Y {
+		return make([]byte, 33)
+	}
+	point.ToAffine()
+	return NewPublicKey(
+		&point.X, &point.Y,
+	).SerializeCompressed()
+}
+
+// GeneratorJacobian sets the passed JacobianPoint to the Generator Point.
+func GeneratorJacobian(jacobian *JacobianPoint) {
+	var k ModNScalar
+	k.SetInt(1)
+	ScalarBaseMultNonConst(&k, jacobian)
+}