Fix affine to projective zero point bug (#552)

## Describe the changes This PR fixes affine to projective functions in bindings by adding a condition if the point in affine form is zero then return the projective zero --------- Co-authored-by: Jeremy Felder <jeremy.felder1@gmail.com>
ingonyama-zk · Jul 4, 2024 · a4b1eb3 · a4b1eb3
1 parent 3108346
commit a4b1eb3
Show file tree

Hide file tree

Showing 12 changed files with 133 additions and 31 deletions.
diff --git a/wrappers/golang/core/internal/mock_curve.go b/wrappers/golang/core/internal/mock_curve.go
@@ -32,9 +32,13 @@ func (p *MockProjective) FromAffine(a MockAffine) MockProjective {
 	z := MockBaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -68,6 +72,11 @@ func (a *MockAffine) FromLimbs(x, y []uint32) MockAffine {
 func (a MockAffine) ToProjective() MockProjective {
 	var z MockBaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p MockProjective
+		return p.Zero()
+	}
+
 	return MockProjective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bls12377/curve.go b/wrappers/golang/curves/bls12377/curve.go
@@ -43,9 +43,13 @@ func (p *Projective) FromAffine(a Affine) Projective {
 	z := BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *Affine) FromLimbs(x, y []uint32) Affine {
 func (a Affine) ToProjective() Projective {
 	var z BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p Projective
+		return p.Zero()
+	}
+
 	return Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bls12377/g2/curve.go b/wrappers/golang/curves/bls12377/g2/curve.go
@@ -43,9 +43,13 @@ func (p *G2Projective) FromAffine(a G2Affine) G2Projective {
 	z := G2BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *G2Affine) FromLimbs(x, y []uint32) G2Affine {
 func (a G2Affine) ToProjective() G2Projective {
 	var z G2BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p G2Projective
+		return p.Zero()
+	}
+
 	return G2Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bls12381/curve.go b/wrappers/golang/curves/bls12381/curve.go
@@ -43,9 +43,13 @@ func (p *Projective) FromAffine(a Affine) Projective {
 	z := BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *Affine) FromLimbs(x, y []uint32) Affine {
 func (a Affine) ToProjective() Projective {
 	var z BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p Projective
+		return p.Zero()
+	}
+
 	return Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bls12381/g2/curve.go b/wrappers/golang/curves/bls12381/g2/curve.go
@@ -43,9 +43,13 @@ func (p *G2Projective) FromAffine(a G2Affine) G2Projective {
 	z := G2BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *G2Affine) FromLimbs(x, y []uint32) G2Affine {
 func (a G2Affine) ToProjective() G2Projective {
 	var z G2BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p G2Projective
+		return p.Zero()
+	}
+
 	return G2Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bn254/curve.go b/wrappers/golang/curves/bn254/curve.go
@@ -43,9 +43,13 @@ func (p *Projective) FromAffine(a Affine) Projective {
 	z := BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *Affine) FromLimbs(x, y []uint32) Affine {
 func (a Affine) ToProjective() Projective {
 	var z BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p Projective
+		return p.Zero()
+	}
+
 	return Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bn254/g2/curve.go b/wrappers/golang/curves/bn254/g2/curve.go
@@ -43,9 +43,13 @@ func (p *G2Projective) FromAffine(a G2Affine) G2Projective {
 	z := G2BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *G2Affine) FromLimbs(x, y []uint32) G2Affine {
 func (a G2Affine) ToProjective() G2Projective {
 	var z G2BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p G2Projective
+		return p.Zero()
+	}
+
 	return G2Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bw6761/curve.go b/wrappers/golang/curves/bw6761/curve.go
@@ -43,9 +43,13 @@ func (p *Projective) FromAffine(a Affine) Projective {
 	z := BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *Affine) FromLimbs(x, y []uint32) Affine {
 func (a Affine) ToProjective() Projective {
 	var z BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p Projective
+		return p.Zero()
+	}
+
 	return Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/bw6761/g2/curve.go b/wrappers/golang/curves/bw6761/g2/curve.go
@@ -43,9 +43,13 @@ func (p *G2Projective) FromAffine(a G2Affine) G2Projective {
 	z := G2BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *G2Affine) FromLimbs(x, y []uint32) G2Affine {
 func (a G2Affine) ToProjective() G2Projective {
 	var z G2BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p G2Projective
+		return p.Zero()
+	}
+
 	return G2Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/curves/grumpkin/curve.go b/wrappers/golang/curves/grumpkin/curve.go
@@ -43,9 +43,13 @@ func (p *Projective) FromAffine(a Affine) Projective {
 	z := BaseField{}
 	z.One()
 
-	p.X = a.X
-	p.Y = a.Y
-	p.Z = z
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	} else {
+		p.X = a.X
+		p.Y = a.Y
+		p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *Affine) FromLimbs(x, y []uint32) Affine {
 func (a Affine) ToProjective() Projective {
 	var z BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		var p Projective
+		return p.Zero()
+	}
+
 	return Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/golang/internal/generator/curves/templates/curve.go.tmpl b/wrappers/golang/internal/generator/curves/templates/curve.go.tmpl
@@ -43,9 +43,13 @@ func (p *{{.CurvePrefix}}Projective) FromAffine(a {{.CurvePrefix}}Affine) {{.Cur
 	z := {{.CurvePrefix}}BaseField{}
 	z.One()
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+		p.Zero()
+	}else{
 	p.X = a.X
 	p.Y = a.Y
-	p.Z = z
+	p.Z = z.One()
+	}
 
 	return *p
 }
@@ -109,6 +113,11 @@ func (a *{{.CurvePrefix}}Affine) FromLimbs(x, y []uint32) {{.CurvePrefix}}Affine
 func (a {{.CurvePrefix}}Affine) ToProjective() {{.CurvePrefix}}Projective {
 	var z {{.CurvePrefix}}BaseField
 
+	if (a.X == z.Zero()) && (a.Y == z.Zero()) {
+        var p {{.CurvePrefix}}Projective
+		return p.Zero()
+	}
+
 	return {{.CurvePrefix}}Projective{
 		X: a.X,
 		Y: a.Y,

diff --git a/wrappers/rust/icicle-core/src/curve.rs b/wrappers/rust/icicle-core/src/curve.rs
@@ -79,6 +79,9 @@ impl<C: Curve> Affine<C> {
     }
 
     pub fn to_projective(&self) -> Projective<C> {
+        if *self == Self::zero() {
+            return Projective::<C>::zero();
+        }
         Projective {
             x: self.x,
             y: self.y,