Export SignatureLen and other constants

secp256k1/fuzzers/secp_test.go

@@ -0,0 +1,53 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package fuzzers
+
+import (
+	"fmt"
+	"testing"
+
+	dcred_secp256k1 "github.com/decred/dcrd/dcrec/secp256k1/v4"
+	"github.com/luxfi/crypto/secp256k1"
+)
+
+func TestFuzzer(t *testing.T) {
+	a, b := "00000000N0000000/R0000000000000000", "0U0000S0000000mkhP000000000000000U"
+	fuzz([]byte(a), []byte(b))
+}
+
+func Fuzz(f *testing.F) {
+	f.Fuzz(func(t *testing.T, a, b []byte) {
+		fuzz(a, b)
+	})
+}
+
+func fuzz(dataP1, dataP2 []byte) {
+	var (
+		curveA = secp256k1.S256()
+		curveB = dcred_secp256k1.S256()
+	)
+	// first point
+	x1, y1 := curveB.ScalarBaseMult(dataP1)
+	// second points
+	x2, y2 := curveB.ScalarBaseMult(dataP2)
+	resAX, resAY := curveA.Add(x1, y1, x2, y2)
+	resBX, resBY := curveB.Add(x1, y1, x2, y2)
+	if resAX.Cmp(resBX) != 0 || resAY.Cmp(resBY) != 0 {
+		fmt.Printf("%s %s %s %s\n", x1, y1, x2, y2)
+		panic(fmt.Sprintf("Addition failed: geth: %s %s btcd: %s %s", resAX, resAY, resBX, resBY))
+	}
+}