common/math, tests/fuzzers: use big.Int clone (ethereum#26006)

common/math/modexp_test.go

@@ -0,0 +1,53 @@
+// Copyright 2022 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 math
+
+import (
+	"math/big"
+	"testing"
+
+	big2 "github.com/holiman/big"
+)
+
+// TestFastModexp tests some cases found during fuzzing.
+func TestFastModexp(t *testing.T) {
+	for i, tc := range []struct {
+		base string
+		exp  string
+		mod  string
+	}{
+		{"0xeffffff900002f00", "0x40000000000000", "0x200"},
+		{"0xf000", "0x4f900b400080000", "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"},
+		{"5", "1435700818", "72"},
+		{"0xffff", "0x300030003000300030003000300030003000302a3000300030003000300030003000300030003000300030003000300030003030623066307f3030783062303430383064303630343036", "0x300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"},
+		{"0x3133", "0x667f00000000000000000000000000ff002a000000000000000000000000000000000000000000000000000000000000667fff30783362773057ee756a6c266134643831646230313630", "0x3030000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"},
+	} {
+		var (
+			base, _  = new(big.Int).SetString(tc.base, 0)
+			exp, _   = new(big.Int).SetString(tc.exp, 0)
+			mod, _   = new(big.Int).SetString(tc.mod, 0)
+			base2, _ = new(big2.Int).SetString(tc.base, 0)
+			exp2, _  = new(big2.Int).SetString(tc.exp, 0)
+			mod2, _  = new(big2.Int).SetString(tc.mod, 0)
+		)
+		var a = new(big2.Int).Exp(base2, exp2, mod2).String()
+		var b = new(big.Int).Exp(base, exp, mod).String()
+		if a != b {
+			t.Errorf("test %d: %#x ^ %#x mod %#x \n have %x\n want %x", i, base, exp, mod, a, b)
+		}
+	}
+}

go.mod

@@ -61,6 +61,7 @@ require (
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/google/pprof v0.0.0-20230207041349-798e818bf904 // indirect
 	github.com/google/uuid v1.3.0 // indirect
+	github.com/holiman/big v0.0.0-20221017200358-a027dc42d04e // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/maruel/panicparse v0.0.0-20160720141634-ad661195ed0e // indirect

go.sum

@@ -141,6 +141,8 @@ github.com/graph-gophers/graphql-go v0.0.0-20191115155744-f33e81362277/go.mod h1
 github.com/hashicorp/golang-lru v0.0.0-20160813221303-0a025b7e63ad/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.3 h1:YPkqC67at8FYaadspW/6uE0COsBxS2656RLEr8Bppgk=
 github.com/hashicorp/golang-lru v0.5.3/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
+github.com/holiman/big v0.0.0-20221017200358-a027dc42d04e h1:pIYdhNkDh+YENVNi3gto8n9hAmRxKxoar0iE6BLucjw=
+github.com/holiman/big v0.0.0-20221017200358-a027dc42d04e/go.mod h1:j9cQbcqHQujT0oKJ38PylVfqohClLr3CvDC+Qcg+lhU=
 github.com/holiman/uint256 v1.2.3 h1:K8UWO1HUJpRMXBxbmaY1Y8IAMZC/RsKB+ArEnnK4l5o=
 github.com/holiman/uint256 v1.2.3/go.mod h1:SC8Ryt4n+UBbPbIBKaG9zbbDlp4jOru9xFZmPzLUTxw=
 github.com/holiman/uint256 v1.2.4 h1:jUc4Nk8fm9jZabQuqr2JzednajVmBpC+oiTiXZJEApU=

tests/fuzzers/modexp/debug/main.go

@@ -0,0 +1,40 @@
+// Copyright 2020 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 main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/XinFinOrg/XDPoSChain/tests/fuzzers/modexp"
+)
+
+func main() {
+	if len(os.Args) != 2 {
+		fmt.Fprintf(os.Stderr, "Usage: debug <file>\n")
+		fmt.Fprintf(os.Stderr, "Example\n")
+		fmt.Fprintf(os.Stderr, "	$ debug ../crashers/4bbef6857c733a87ecf6fd8b9e7238f65eb9862a\n")
+		os.Exit(1)
+	}
+	crasher := os.Args[1]
+	data, err := os.ReadFile(crasher)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error loading crasher %v: %v", crasher, err)
+		os.Exit(1)
+	}
+	modexp.Fuzz(data)
+}

tests/fuzzers/modexp/modexp-fuzzer.go

@@ -21,8 +21,8 @@ import (
 	"math/big"
 
 	"github.com/XinFinOrg/XDPoSChain/common"
-	"github.com/XinFinOrg/XDPoSChain/common/math"
 	"github.com/XinFinOrg/XDPoSChain/core/vm"
+	big2 "github.com/holiman/big"
 )
 
 // The function must return
@@ -55,18 +55,21 @@ func Fuzz(input []byte) int {
 	input = input[96:]
 	// Retrieve the operands and execute the exponentiation
 	var (
-		base = new(big.Int).SetBytes(getData(input, 0, baseLen))
-		exp  = new(big.Int).SetBytes(getData(input, baseLen, expLen))
-		mod  = new(big.Int).SetBytes(getData(input, baseLen+expLen, modLen))
+		base  = new(big.Int).SetBytes(getData(input, 0, baseLen))
+		exp   = new(big.Int).SetBytes(getData(input, baseLen, expLen))
+		mod   = new(big.Int).SetBytes(getData(input, baseLen+expLen, modLen))
+		base2 = new(big2.Int).SetBytes(getData(input, 0, baseLen))
+		exp2  = new(big2.Int).SetBytes(getData(input, baseLen, expLen))
+		mod2  = new(big2.Int).SetBytes(getData(input, baseLen+expLen, modLen))
 	)
 	if mod.BitLen() == 0 {
 		// Modulo 0 is undefined, return zero
 		return -1
 	}
-	var a = math.FastExp(new(big.Int).Set(base), new(big.Int).Set(exp), new(big.Int).Set(mod))
-	var b = base.Exp(base, exp, mod)
-	if a.Cmp(b) != 0 {
-		panic(fmt.Sprintf("Inequality %x != %x", a, b))
+	var a = new(big2.Int).Exp(base2, exp2, mod2).String()
+	var b = new(big.Int).Exp(base, exp, mod).String()
+	if a != b {
+		panic(fmt.Sprintf("Inequality %#x ^ %#x mod %#x \n have %s\n want %s", base, exp, mod, a, b))
 	}
 	return 1
 }