From 9a8121d049d3beb7f553bbc3e966e2c640c1cc76 Mon Sep 17 00:00:00 2001
From: Antoine Rondelet <rondelet.antoine@gmail.com>
Date: Wed, 22 May 2019 12:23:57 +0100
Subject: [PATCH 1/3] Added checks for nil pointers in Marshal functions

---
 bn256.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/bn256.go b/bn256.go
index 3a07377..f48a7a5 100644
--- a/bn256.go
+++ b/bn256.go
@@ -105,6 +105,10 @@ func (e *G1) Marshal() []byte {
 	// Each value is a 256-bit number.
 	const numBytes = 256 / 8
 
+	if e.p == nil {
+		e.p = &curvePoint{}
+	}
+
 	e.p.MakeAffine()
 	ret := make([]byte, numBytes*2)
 	if e.p.IsInfinity() {
@@ -391,6 +395,10 @@ func (e *GT) Marshal() []byte {
 	// Each value is a 256-bit number.
 	const numBytes = 256 / 8
 
+	if e.p == nil {
+		e.p = &gfP12{}
+	}
+
 	ret := make([]byte, numBytes*12)
 	temp := &gfP{}
 

From a8faec7df68ce8b4869ac5cf0c7bcfaab883fd38 Mon Sep 17 00:00:00 2001
From: armfazh <armfazh@cloudflare.com>
Date: Wed, 22 May 2019 11:02:01 -0700
Subject: [PATCH 2/3] Set identities on marshaling functions for G1,G2,GT.

- Adds tests for verifying the issue pointed at #8.
---
 bn256.go      |  3 +++
 bn256_test.go | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/bn256.go b/bn256.go
index f48a7a5..d307e60 100644
--- a/bn256.go
+++ b/bn256.go
@@ -107,6 +107,7 @@ func (e *G1) Marshal() []byte {
 
 	if e.p == nil {
 		e.p = &curvePoint{}
+		e.p.SetInfinity()
 	}
 
 	e.p.MakeAffine()
@@ -236,6 +237,7 @@ func (e *G2) Marshal() []byte {
 
 	if e.p == nil {
 		e.p = &twistPoint{}
+		e.p.SetInfinity()
 	}
 
 	e.p.MakeAffine()
@@ -397,6 +399,7 @@ func (e *GT) Marshal() []byte {
 
 	if e.p == nil {
 		e.p = &gfP12{}
+		e.p.SetOne()
 	}
 
 	ret := make([]byte, numBytes*12)
diff --git a/bn256_test.go b/bn256_test.go
index f2a6223..ad168fa 100644
--- a/bn256_test.go
+++ b/bn256_test.go
@@ -41,6 +41,18 @@ func TestG1Marshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
+
+	Ga = new(G1)
+	ma = Ga.Marshal()
+
+	one := &curvePoint{}
+	one.SetInfinity()
+	Gb = &G1{p: one}
+	mb = Gb.Marshal()
+
+	if !bytes.Equal(ma, mb) {
+		t.Fatal("bytes are different")
+	}
 }
 
 func TestG2(t *testing.T) {
@@ -76,6 +88,18 @@ func TestG2Marshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
+
+	Ga = new(G2)
+	ma = Ga.Marshal()
+
+	one := &twistPoint{}
+	one.SetInfinity()
+	Gb = &G2{p: one}
+	mb = Gb.Marshal()
+
+	if !bytes.Equal(ma, mb) {
+		t.Fatal("bytes are different")
+	}
 }
 
 func TestGT(t *testing.T) {
@@ -114,6 +138,18 @@ func TestGTMarshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
+
+	Ga = new(GT)
+	ma = Ga.Marshal()
+
+	one := &gfP12{}
+	one.SetOne()
+	Gb = &GT{p: one}
+	mb = Gb.Marshal()
+
+	if !bytes.Equal(ma, mb) {
+		t.Fatal("bytes are different")
+	}
 }
 
 func TestBilinearity(t *testing.T) {

From 0a352d728d8f703090a99402e7ae750c3cabc2f6 Mon Sep 17 00:00:00 2001
From: armfazh <armfazh@cloudflare.com>
Date: Thu, 23 May 2019 10:22:55 -0700
Subject: [PATCH 3/3] Removing extra tests and SetInfinity calls.

---
 bn256.go      |  2 --
 bn256_test.go | 36 ------------------------------------
 2 files changed, 38 deletions(-)

diff --git a/bn256.go b/bn256.go
index d307e60..9d4cc39 100644
--- a/bn256.go
+++ b/bn256.go
@@ -107,7 +107,6 @@ func (e *G1) Marshal() []byte {
 
 	if e.p == nil {
 		e.p = &curvePoint{}
-		e.p.SetInfinity()
 	}
 
 	e.p.MakeAffine()
@@ -237,7 +236,6 @@ func (e *G2) Marshal() []byte {
 
 	if e.p == nil {
 		e.p = &twistPoint{}
-		e.p.SetInfinity()
 	}
 
 	e.p.MakeAffine()
diff --git a/bn256_test.go b/bn256_test.go
index ad168fa..f2a6223 100644
--- a/bn256_test.go
+++ b/bn256_test.go
@@ -41,18 +41,6 @@ func TestG1Marshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
-
-	Ga = new(G1)
-	ma = Ga.Marshal()
-
-	one := &curvePoint{}
-	one.SetInfinity()
-	Gb = &G1{p: one}
-	mb = Gb.Marshal()
-
-	if !bytes.Equal(ma, mb) {
-		t.Fatal("bytes are different")
-	}
 }
 
 func TestG2(t *testing.T) {
@@ -88,18 +76,6 @@ func TestG2Marshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
-
-	Ga = new(G2)
-	ma = Ga.Marshal()
-
-	one := &twistPoint{}
-	one.SetInfinity()
-	Gb = &G2{p: one}
-	mb = Gb.Marshal()
-
-	if !bytes.Equal(ma, mb) {
-		t.Fatal("bytes are different")
-	}
 }
 
 func TestGT(t *testing.T) {
@@ -138,18 +114,6 @@ func TestGTMarshal(t *testing.T) {
 	if !bytes.Equal(ma, mb) {
 		t.Fatal("bytes are different")
 	}
-
-	Ga = new(GT)
-	ma = Ga.Marshal()
-
-	one := &gfP12{}
-	one.SetOne()
-	Gb = &GT{p: one}
-	mb = Gb.Marshal()
-
-	if !bytes.Equal(ma, mb) {
-		t.Fatal("bytes are different")
-	}
 }
 
 func TestBilinearity(t *testing.T) {