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113 lines
2.5 KiB
113 lines
2.5 KiB
#ifndef _SECP256K1_GROUP_
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#define _SECP256K1_GROUP_
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#include <string>
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#include "num.h"
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#include "field.h"
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namespace secp256k1 {
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class GroupElemJac;
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/** Defines a point on the secp256k1 curve (y^2 = x^3 + 7) */
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class GroupElem {
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protected:
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bool fInfinity;
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FieldElem x;
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FieldElem y;
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public:
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/** Creates the point at infinity */
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GroupElem();
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/** Creates the point with given affine coordinates */
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GroupElem(const FieldElem &xin, const FieldElem &yin);
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/** Checks whether this is the point at infinity */
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bool IsInfinity() const;
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void SetNeg(const GroupElem &p);
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void GetX(FieldElem &xout);
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void GetY(FieldElem &yout);
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std::string ToString() const;
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void SetJac(GroupElemJac &jac);
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friend class GroupElemJac;
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};
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/** Represents a point on the secp256k1 curve, with jacobian coordinates */
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class GroupElemJac : private GroupElem {
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protected:
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FieldElem z;
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public:
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/** Creates the point at infinity */
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GroupElemJac();
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/** Creates the point with given affine coordinates */
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GroupElemJac(const FieldElem &xin, const FieldElem &yin);
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GroupElemJac(const GroupElem &in);
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void SetJac(const GroupElemJac &jac);
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void SetAffine(const GroupElem &aff);
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/** Checks whether this is a non-infinite point on the curve */
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bool IsValid() const;
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/** Returns the affine coordinates of this point */
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void GetAffine(GroupElem &aff);
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void GetX(FieldElem &xout);
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void GetY(FieldElem &yout);
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bool IsInfinity() const;
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void SetNeg(const GroupElemJac &p);
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/** Sets this point to have a given X coordinate & given Y oddness */
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void SetCompressed(const FieldElem &xin, bool fOdd);
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/** Sets this point to be the EC double of another */
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void SetDouble(const GroupElemJac &p);
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/** Sets this point to be the EC addition of two others */
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void SetAdd(const GroupElemJac &p, const GroupElemJac &q);
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/** Sets this point to be the EC addition of two others (one of which is in affine coordinates) */
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void SetAdd(const GroupElemJac &p, const GroupElem &q);
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std::string ToString() const;
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void SetMulLambda(const GroupElemJac &p);
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};
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class GroupConstants {
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private:
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const FieldElem g_x;
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const FieldElem g_y;
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public:
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const Number order;
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const GroupElem g;
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const FieldElem beta;
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const Number lambda, a1b2, b1, a2;
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GroupConstants();
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};
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const GroupConstants &GetGroupConst();
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void SplitExp(const Number &exp, Number &exp1, Number &exp2);
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}
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#endif
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