fix(consensus): hardening header verification #33860 (#2071)

consensus/XDPoS/engines/engine_v1/engine.go

@@ -235,7 +235,7 @@ func (x *XDPoS_v1) verifyCascadingFields(chain consensus.ChainReader, header *ty
 		return utils.ErrInvalidTimestamp
 	}
 	// Verify the header's EIP-1559 attributes.
-	if err := eip1559.VerifyEip1559Header(chain.Config(), header); err != nil {
+	if err := eip1559.VerifyEip1559Header(chain.Config(), parent, header); err != nil {
 		return err
 	}
 

consensus/XDPoS/engines/engine_v2/verifyHeader.go

@@ -110,7 +110,7 @@ func (x *XDPoS_v2) verifyHeader(chain consensus.ChainReader, header *types.Heade
 		return utils.ErrInvalidUncleHash
 	}
 	// Verify the header's EIP-1559 attributes.
-	if err := eip1559.VerifyEip1559Header(chain.Config(), header); err != nil {
+	if err := eip1559.VerifyEip1559Header(chain.Config(), parent, header); err != nil {
 		return err
 	}
 	if header.Difficulty.Cmp(big.NewInt(1)) != 0 {

consensus/ethash/consensus.go

@@ -202,7 +202,7 @@ func (ethash *Ethash) verifyHeader(chain consensus.ChainReader, header, parent *
 		return err
 	}
 	// Verify the header's EIP-1559 attributes.
-	if err := eip1559.VerifyEip1559Header(chain.Config(), header); err != nil {
+	if err := eip1559.VerifyEip1559Header(chain.Config(), parent, header); err != nil {
 		return err
 	}
 

consensus/misc/eip1559/eip1559.go

@@ -29,7 +29,7 @@ import (
 // VerifyEip1559Header verifies some header attributes which were changed in EIP-1559,
 // - gas limit check
 // - basefee check
-func VerifyEip1559Header(config *params.ChainConfig, header *types.Header) error {
+func VerifyEip1559Header(config *params.ChainConfig, parent, header *types.Header) error {
 	if !config.IsEIP1559(header.Number) {
 		if header.BaseFee != nil {
 			return fmt.Errorf("invalid baseFee: have %s, want <nil>",
@@ -42,6 +42,10 @@ func VerifyEip1559Header(config *params.ChainConfig, header *types.Header) error
 	if header.BaseFee == nil {
 		return errors.New("header is missing baseFee")
 	}
+	// Verify the parent header is not malformed
+	if parent != nil && config.IsEIP1559(parent.Number) && parent.BaseFee == nil {
+		return errors.New("parent header is missing baseFee")
+	}
 
 	// Verify the baseFee is correct based on the current header.
 	expectedBaseFee := CalcBaseFee(config, header)

consensus/misc/eip1559/eip1559_test.go

@@ -0,0 +1,81 @@
+// 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 eip1559
+
+import (
+	"math/big"
+	"testing"
+
+	"github.com/XinFinOrg/XDPoSChain/common"
+	"github.com/XinFinOrg/XDPoSChain/core/types"
+	"github.com/XinFinOrg/XDPoSChain/params"
+)
+
+func testConfigEip1559() *params.ChainConfig {
+	config := *params.TestChainConfig
+	config.Eip1559Block = big.NewInt(1)
+	return &config
+}
+
+func TestVerifyEip1559HeaderParentBaseFee(t *testing.T) {
+	config := testConfigEip1559()
+
+	for _, tc := range []struct {
+		name      string
+		parent    *types.Header
+		headerNum int64
+		wantOk    bool
+	}{
+		{
+			name: "eip1559 parent missing basefee",
+			parent: &types.Header{
+				Number: big.NewInt(1),
+			},
+			headerNum: 2,
+			wantOk:    false,
+		},
+		{
+			name: "eip1559 parent with basefee",
+			parent: &types.Header{
+				Number:  big.NewInt(1),
+				BaseFee: new(big.Int).Set(common.BaseFee),
+			},
+			headerNum: 2,
+			wantOk:    true,
+		},
+		{
+			name: "pre-eip1559 parent ignores basefee",
+			parent: &types.Header{
+				Number: big.NewInt(0),
+			},
+			headerNum: 1,
+			wantOk:    true,
+		},
+	} {
+		header := &types.Header{
+			Number:  big.NewInt(tc.headerNum),
+			BaseFee: new(big.Int).Set(common.BaseFee),
+		}
+		err := VerifyEip1559Header(config, tc.parent, header)
+		if tc.wantOk && err != nil {
+			t.Fatalf("%s: expected no error, got %v", tc.name, err)
+		}
+		if !tc.wantOk && err == nil {
+			t.Fatalf("%s: expected error, got nil", tc.name)
+		}
+	}
+}