Merge pull request #14993 from karalabe/bn256-precompile-fixes

core/vm, crypto/bn256: fix bn256 use and pairing corner case

4 files changed, 81 insertions, 16 deletions

diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index b885d42bb..790d42bbe 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -307,8 +307,9 @@ func (c *bn256Add) Run(input []byte) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	x.Add(x, y)
-	return x.Marshal(), nil
+	res := new(bn256.G1)
+	res.Add(x, y)
+	return res.Marshal(), nil
 }
 
 // bn256ScalarMul implements a native elliptic curve scalar multiplication.
@@ -324,8 +325,9 @@ func (c *bn256ScalarMul) Run(input []byte) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	p.ScalarMult(p, new(big.Int).SetBytes(getData(input, 64, 32)))
-	return p.Marshal(), nil
+	res := new(bn256.G1)
+	res.ScalarMult(p, new(big.Int).SetBytes(getData(input, 64, 32)))
+	return res.Marshal(), nil
 }
 
 var (
@@ -370,8 +372,7 @@ func (c *bn256Pairing) Run(input []byte) ([]byte, error) {
 		ts = append(ts, t)
 	}
 	// Execute the pairing checks and return the results
-	ok := bn256.PairingCheck(cs, ts)
-	if ok {
+	if bn256.PairingCheck(cs, ts) {
 		return true32Byte, nil
 	}
 	return false32Byte, nil
diff --git a/core/vm/contracts_test.go b/core/vm/contracts_test.go
index 9bc860b5f..022070ab8 100644
--- a/core/vm/contracts_test.go
+++ b/core/vm/contracts_test.go
@@ -93,7 +93,8 @@ var modexpTests = []precompiledTest{
 	}, {
 		input:    "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",
 		expected: "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",
-		name:     "nagydani-5-pow0x10001"},
+		name:     "nagydani-5-pow0x10001",
+	},
 }
 
 // bn256AddTests are the test and benchmark data for the bn256 addition precompiled
@@ -106,7 +107,64 @@ var bn256AddTests = []precompiledTest{
 	}, {
 		input:    "2243525c5efd4b9c3d3c45ac0ca3fe4dd85e830a4ce6b65fa1eeaee202839703301d1d33be6da8e509df21cc35964723180eed7532537db9ae5e7d48f195c91518b18acfb4c2c30276db5411368e7185b311dd124691610c5d3b74034e093dc9063c909c4720840cb5134cb9f59fa749755796819658d32efc0d288198f37266",
 		expected: "2bd3e6d0f3b142924f5ca7b49ce5b9d54c4703d7ae5648e61d02268b1a0a9fb721611ce0a6af85915e2f1d70300909ce2e49dfad4a4619c8390cae66cefdb204",
-		name:     "chfast2"},
+		name:     "chfast2",
+	}, {
+		input:    "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio1",
+	}, {
+		input:    "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio2",
+	}, {
+		input:    "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio3",
+	}, {
+		input:    "",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio4",
+	}, {
+		input:    "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio5",
+	}, {
+		input:    "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		expected: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		name:     "cdetrio6",
+	}, {
+		input:    "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		name:     "cdetrio7",
+	}, {
+		input:    "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		expected: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		name:     "cdetrio8",
+	}, {
+		input:    "0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		name:     "cdetrio9",
+	}, {
+		input:    "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		name:     "cdetrio10",
+	}, {
+		input:    "0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
+		expected: "030644e72e131a029b85045b68181585d97816a916871ca8d3c208c16d87cfd315ed738c0e0a7c92e7845f96b2ae9c0a68a6a449e3538fc7ff3ebf7a5a18a2c4",
+		name:     "cdetrio11",
+	}, {
+		input:    "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "030644e72e131a029b85045b68181585d97816a916871ca8d3c208c16d87cfd315ed738c0e0a7c92e7845f96b2ae9c0a68a6a449e3538fc7ff3ebf7a5a18a2c4",
+		name:     "cdetrio12",
+	}, {
+		input:    "17c139df0efee0f766bc0204762b774362e4ded88953a39ce849a8a7fa163fa901e0559bacb160664764a357af8a9fe70baa9258e0b959273ffc5718c6d4cc7c039730ea8dff1254c0fee9c0ea777d29a9c710b7e616683f194f18c43b43b869073a5ffcc6fc7a28c30723d6e58ce577356982d65b833a5a5c15bf9024b43d98",
+		expected: "15bf2bb17880144b5d1cd2b1f46eff9d617bffd1ca57c37fb5a49bd84e53cf66049c797f9ce0d17083deb32b5e36f2ea2a212ee036598dd7624c168993d1355f",
+		name:     "cdetrio13",
+	}, {
+		input:    "17c139df0efee0f766bc0204762b774362e4ded88953a39ce849a8a7fa163fa901e0559bacb160664764a357af8a9fe70baa9258e0b959273ffc5718c6d4cc7c17c139df0efee0f766bc0204762b774362e4ded88953a39ce849a8a7fa163fa92e83f8d734803fc370eba25ed1f6b8768bd6d83887b87165fc2434fe11a830cb00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		expected: "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+		name:     "cdetrio14",
+	},
 }
 
 // bn256ScalarMulTests are the test and benchmark data for the bn256 scalar
@@ -123,7 +181,8 @@ var bn256ScalarMulTests = []precompiledTest{
 	}, {
 		input:    "025a6f4181d2b4ea8b724290ffb40156eb0adb514c688556eb79cdea0752c2bb2eff3f31dea215f1eb86023a133a996eb6300b44da664d64251d05381bb8a02e183227397098d014dc2822db40c0ac2ecbc0b548b438e5469e10460b6c3e7ea3",
 		expected: "14789d0d4a730b354403b5fac948113739e276c23e0258d8596ee72f9cd9d3230af18a63153e0ec25ff9f2951dd3fa90ed0197bfef6e2a1a62b5095b9d2b4a27",
-		name:     "chfast3"},
+		name:     "chfast3",
+	},
 }
 
 // bn256PairingTests are the test and benchmark data for the bn256 pairing check
diff --git a/crypto/bn256/bn256.go b/crypto/bn256/bn256.go
index 92418369b..7144c31a8 100644
--- a/crypto/bn256/bn256.go
+++ b/crypto/bn256/bn256.go
@@ -379,16 +379,22 @@ func Pair(g1 *G1, g2 *G2) *GT {
 	return &GT{optimalAte(g2.p, g1.p, new(bnPool))}
 }
 
+// PairingCheck calculates the Optimal Ate pairing for a set of points.
 func PairingCheck(a []*G1, b []*G2) bool {
 	pool := new(bnPool)
-	e := newGFp12(pool)
-	e.SetOne()
+
+	acc := newGFp12(pool)
+	acc.SetOne()
+
 	for i := 0; i < len(a); i++ {
-		new_e := miller(b[i].p, a[i].p, pool)
-		e.Mul(e, new_e, pool)
+		if a[i].p.IsInfinity() || b[i].p.IsInfinity() {
+			continue
+		}
+		acc.Mul(acc, miller(b[i].p, a[i].p, pool), pool)
 	}
-	ret := finalExponentiation(e, pool)
-	e.Put(pool)
+	ret := finalExponentiation(acc, pool)
+	acc.Put(pool)
+
 	return ret.IsOne()
 }
 
diff --git a/crypto/bn256/optate.go b/crypto/bn256/optate.go
index 68716b62b..9d6957062 100644
--- a/crypto/bn256/optate.go
+++ b/crypto/bn256/optate.go
@@ -393,6 +393,5 @@ func optimalAte(a *twistPoint, b *curvePoint, pool *bnPool) *gfP12 {
 	if a.IsInfinity() || b.IsInfinity() {
 		ret.SetOne()
 	}
-
 	return ret
 }