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compiles at least

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This commit is contained in:
Pieter Wuille 2013-03-07 00:03:46 +01:00
parent f610bf9f90
commit 16d5180911
1 changed files with 73 additions and 57 deletions
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130
secp256k1.cpp
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@ -361,6 +361,8 @@ public:
} }
}; };
template<typename F> class GroupElemJac;
template<typename F> class GroupElem { template<typename F> class GroupElem {
protected: protected:
bool fInfinity; bool fInfinity;
@ -369,35 +371,41 @@ protected:
public: public:
void SetXY(const F &xin, const F &yin) {
fInfinity = false;
this->x = xin;
this->y = yin;
}
/** Creates the point at infinity */ /** Creates the point at infinity */
GroupElem() { GroupElem() {
fInfinity = true; this->fInfinity = true;
} }
/** Creates the point with given affine coordinates */ /** Creates the point with given affine coordinates */
GroupElem(const F &xin, const F &yin) { GroupElem(const F &xin, const F &yin) {
fInfinity = false; SetXY(xin,yin);
x = xin;
y = yin;
} }
/** Checks whether this is the point at infinity */ /** Checks whether this is the point at infinity */
bool IsInfinity() const { bool IsInfinity() const {
return fInfinity; return this->fInfinity;
} }
void SetNeg(GroupElem<F> &p) { void SetNeg(GroupElem<F> &p) {
fInfinity = p.fInfinity; this->fInfinity = p.fInfinity;
x = p.x; this->x = p.x;
p.y.Normalize(); p.y.Normalize();
y.SetNeg(p.y, 1); this->y.SetNeg(p.y, 1);
} }
std::string ToString() { std::string ToString() {
if (fInfinity) if (this->fInfinity)
return "(inf)"; return "(inf)";
return "(" + xt.ToString() + "," + yt.ToString() + ")"; return "(" + this->x.ToString() + "," + this->y.ToString() + ")";
} }
friend class GroupElemJac<F>;
}; };
template<typename F> class GroupElemJac : public GroupElem<F> { template<typename F> class GroupElemJac : public GroupElem<F> {
@ -413,15 +421,15 @@ public:
/** Checks whether this is a non-infinite point on the curve */ /** Checks whether this is a non-infinite point on the curve */
bool IsValid() { bool IsValid() {
if (IsInfinity()) if (this->IsInfinity())
return false; return false;
// y^2 = x^3 + 7 // y^2 = x^3 + 7
// (Y/Z^3)^2 = (X/Z^2)^3 + 7 // (Y/Z^3)^2 = (X/Z^2)^3 + 7
// Y^2 / Z^6 = X^3 / Z^6 + 7 // Y^2 / Z^6 = X^3 / Z^6 + 7
// Y^2 = X^3 + 7*Z^6 // Y^2 = X^3 + 7*Z^6
F y2; y2.SetSquare(y); F y2; y2.SetSquare(this->y);
F x3; x3.SetSquare(x); x3.SetMult(x3,x); F x3; x3.SetSquare(this->x); x3.SetMult(x3,this->x);
F z2; z2.SetSquare(z); F z2; z2.SetSquare(this->z);
F z6; z6.SetSquare(z2); z6.SetMult(z6,z2); F z6; z6.SetSquare(z2); z6.SetMult(z6,z2);
z6 *= 7; z6 *= 7;
x3 += z6; x3 += z6;
@ -435,55 +443,54 @@ public:
z2.SetSquare(z); z2.SetSquare(z);
F z3; F z3;
z3.SetMult(z,z2); z3.SetMult(z,z2);
x.SetMult(x,z2); this->x.SetMult(this->x,z2);
y.SetMult(y,z3); this->y.SetMult(this->y,z3);
z = F(1); this->z = F(1);
aff.x = x; aff.SetXY(this->x,this->y);
aff.y = y;
} }
/** Sets this point to have a given X coordinate & given Y oddness */ /** Sets this point to have a given X coordinate & given Y oddness */
void SetCompressed(const F &xin, bool fOdd) { void SetCompressed(const F &xin, bool fOdd) {
x = xin; this->x = xin;
F x2; x2.SetSquare(x); F x2; x2.SetSquare(this->x);
F x3; x3.SetMult(x,x2); F x3; x3.SetMult(this->x,x2);
fInfinity = false; this->fInfinity = false;
F c(7); F c(7);
c += x3; c += x3;
y.SetSquareRoot(c); this->y.SetSquareRoot(c);
z = F(1); this->z = F(1);
if (y.IsOdd() != fOdd) if (this->y.IsOdd() != fOdd)
y.SetNeg(y,1); this->y.SetNeg(this->y,1);
} }
/** Sets this point to be the EC double of another */ /** Sets this point to be the EC double of another */
void SetDouble(const GroupElemJac<F> &p) { void SetDouble(const GroupElemJac<F> &p) {
if (p.fInfinity || y.IsZero()) { if (p.fInfinity || this->y.IsZero()) {
fInfinity = true; this->fInfinity = true;
return; return;
} }
F t1,t2,t3,t4,t5; F t1,t2,t3,t4,t5;
z.SetMult(p.y,p.z); this->z.SetMult(p.y,p.z);
z *= 2; // Z' = 2*Y*Z (2) this->z *= 2; // Z' = 2*Y*Z (2)
t1.SetSquare(p.x); t1.SetSquare(p.x);
t1 *= 3; // T1 = 3*X^2 (3) t1 *= 3; // T1 = 3*X^2 (3)
t2.SetSquare(t1); // T2 = 9*X^4 (1) t2.SetSquare(t1); // T2 = 9*X^4 (1)
t3.SetSquare(y); t3.SetSquare(p.y);
t3 *= 2; // T3 = 2*Y^2 (2) t3 *= 2; // T3 = 2*Y^2 (2)
t4.SetSquare(t3); t4.SetSquare(t3);
t4 *= 2; // T4 = 8*Y^4 (2) t4 *= 2; // T4 = 8*Y^4 (2)
t3.SetMult(x,t3); // T3 = 2*X*Y^2 (1) t3.SetMult(p.x,t3); // T3 = 2*X*Y^2 (1)
x = t3; this->x = t3;
x *= 4; // X' = 8*X*Y^2 (4) this->x *= 4; // X' = 8*X*Y^2 (4)
x.SetNeg(x,4); // X' = -8*X*Y^2 (5) this->x.SetNeg(this->x,4); // X' = -8*X*Y^2 (5)
x += t2; // X' = 9*X^4 - 8*X*Y^2 (6) this->x += t2; // X' = 9*X^4 - 8*X*Y^2 (6)
t2.SetNeg(t2,1); // T2 = -9*X^4 (2) t2.SetNeg(t2,1); // T2 = -9*X^4 (2)
t3 *= 6; // T3 = 12*X*Y^2 (6) t3 *= 6; // T3 = 12*X*Y^2 (6)
t3 += t2; // T3 = 12*X*Y^2 - 9*X^4 (8) t3 += t2; // T3 = 12*X*Y^2 - 9*X^4 (8)
y.SetMult(t1,t3); // Y' = 36*X^3*Y^2 - 27*X^6 (1) this->y.SetMult(t1,t3); // Y' = 36*X^3*Y^2 - 27*X^6 (1)
t2.SetNeg(t4,2); // T2 = -8*Y^4 (3) t2.SetNeg(t4,2); // T2 = -8*Y^4 (3)
y += t2; // Y' = 36*X^3*Y^2 - 27*X^6 - 8*Y^4 (4) this->y += t2; // Y' = 36*X^3*Y^2 - 27*X^6 - 8*Y^4 (4)
} }
/** Sets this point to be the EC addition of two others */ /** Sets this point to be the EC addition of two others */
@ -496,7 +503,7 @@ public:
*this = p; *this = p;
return; return;
} }
fInfinity = false; this->fInfinity = false;
const F &x1 = p.x, &y1 = p.y, &z1 = p.z, &x2 = q.x, &y2 = q.y, &z2 = q.z; const F &x1 = p.x, &y1 = p.y, &z1 = p.z, &x2 = q.x, &y2 = q.y, &z2 = q.z;
F z22; z22.SetSquare(z2); F z22; z22.SetSquare(z2);
F z12; z12.SetSquare(z1); F z12; z12.SetSquare(z1);
@ -508,7 +515,7 @@ public:
if (s1 == s2) { if (s1 == s2) {
SetDouble(p); SetDouble(p);
} else { } else {
fInfinity = true; this->fInfinity = true;
} }
return; return;
} }
@ -517,35 +524,39 @@ public:
F r2; r2.SetSquare(r); F r2; r2.SetSquare(r);
F h2; h2.SetSquare(h); F h2; h2.SetSquare(h);
F h3; h3.SetMult(h,h2); F h3; h3.SetMult(h,h2);
z.SetMult(p.z,q.z); z.SetMult(z, h); this->z.SetMult(p.z,q.z); this->z.SetMult(z, h);
F t; t.SetMult(u1,h2); F t; t.SetMult(u1,h2);
x = t; x *= 2; x += h3; x.SetNeg(x,3); x += r2; this->x = t; this->x *= 2; this->x += h3; this->x.SetNeg(this->x,3); this->x += r2;
y.SetNeg(x,5); y += t; y.SetMult(y,r); this->y.SetNeg(this->x,5); this->y += t; this->y.SetMult(this->y,r);
h3.SetMult(h3,s1); h3.SetNeg(h3,1); h3.SetMult(h3,s1); h3.SetNeg(h3,1);
y += h3; this->y += h3;
} }
/** Sets this point to be the EC addition of two others (one of which is in affine coordinates) */ /** Sets this point to be the EC addition of two others (one of which is in affine coordinates) */
void SetAdd(const GroupElemJac<F> &p, const GroupElem<F> &q) { void SetAdd(const GroupElemJac<F> &p, const GroupElem<F> &q) {
if (p.fInfinity) { if (p.fInfinity) {
*this = q; this->x = q.x;
z = F(1); this->y = q.y;
this->fInfinity = q.fInfinity;
this->z = F(1);
return; return;
} }
if (q.fInfinity) { if (q.fInfinity) {
*this = p; *this = p;
return; return;
} }
fInfinity = false; this->fInfinity = false;
const F &u1 = p.x, &s1 = p.y, &z1 = p.z, &x2 = q.x, &y2 = q.y; const F &x1 = p.x, &y1 = p.y, &z1 = p.z, &x2 = q.x, &y2 = q.y;
F z12; z12.SetSquare(z1); F z12; z12.SetSquare(z1);
F u1 = x1;
F u2; u2.SetMult(x2, z12); F u2; u2.SetMult(x2, z12);
F s1 = y1;
F s2; s2.SetMult(y2, z12); s2.SetMult(s2, z1); F s2; s2.SetMult(y2, z12); s2.SetMult(s2, z1);
if (u1 == u2) { if (u1 == u2) {
if (s1 == s2) { if (s1 == s2) {
SetDouble(p); SetDouble(p);
} else { } else {
fInfinity = true; this->fInfinity = true;
} }
return; return;
} }
@ -554,17 +565,17 @@ public:
F r2; r2.SetSquare(r); F r2; r2.SetSquare(r);
F h2; h2.SetSquare(h); F h2; h2.SetSquare(h);
F h3; h3.SetMult(h,h2); F h3; h3.SetMult(h,h2);
z = p.z; z.SetMult(z, h); this->z = p.z; this->z.SetMult(z, h);
F t; t.SetMult(u1,h2); F t; t.SetMult(u1,h2);
x = t; x *= 2; x += h3; x.SetNeg(x,3); x += r2; this->x = t; this->x *= 2; this->x += h3; this->x.SetNeg(this->x,3); this->x += r2;
y.SetNeg(x,5); y += t; y.SetMult(y,r); this->y.SetNeg(this->x,5); this->y += t; this->y.SetMult(this->y,r);
h3.SetMult(h3,s1); h3.SetNeg(h3,1); h3.SetMult(h3,s1); h3.SetNeg(h3,1);
y += h3; this->y += h3;
} }
std::string ToString() { std::string ToString() {
GroupElem<F> aff; GroupElem<F> aff;
GetAffine(aff); this->GetAffine(aff);
return aff.ToString(); return aff.ToString();
} }
}; };
@ -576,10 +587,15 @@ using namespace secp256k1;
int main() { int main() {
FieldElem f1,f2; FieldElem f1,f2;
f1.SetHex("8b30bbe9ae2a990696b22f670709dff3727fd8bc04d3362c6c7bf458e2846004"); f1.SetHex("8b30bbe9ae2a990696b22f670709dff3727fd8bc04d3362c6c7bf458e2846004");
f2.SetHex("a357ae915c4a65281309edf20504740f1eb3343990216b4f81063cb65f2f7e0f"); f2.SetHex("a357ae915c4a65281309edf20504740f1eb3333990216b4f81063cb65f2f7e0f");
GroupElemJac<FieldElem> g1; g1.SetCompressed(f1,false); GroupElemJac<FieldElem> g1; g1.SetCompressed(f1,false);
GroupElemJac<FieldElem> g2; g2.SetCompressed(f2,false); GroupElemJac<FieldElem> g2; g2.SetCompressed(f2,false);
printf("g1: %s (%s)\n", g1.ToString().c_str(), g1.IsValid() ? "ok" : "fail"); printf("g1: %s (%s)\n", g1.ToString().c_str(), g1.IsValid() ? "ok" : "fail");
printf("g2: %s (%s)\n", g1.ToString().c_str(), g1.IsValid() ? "ok" : "fail"); printf("g2: %s (%s)\n", g2.ToString().c_str(), g2.IsValid() ? "ok" : "fail");
GroupElem<FieldElem> g2a; g2.GetAffine(g2a);
printf("g2a:%s\n", g2a.ToString().c_str());
for (int i=0; i<1000000; i++)
g1.SetAdd(g1,g2a);
printf("res:%s (%s)\n", g1.ToString().c_str(), g1.IsValid() ? "ok" : "fail");
return 0; return 0;
} }