eupgrade/cancun: verify no blobs in header

consensus/dummy/consensus.go

@@ -263,6 +263,9 @@ func (self *DummyEngine) verifyHeader(chain consensus.ChainHeaderReader, header
 		if err := eip4844.VerifyEIP4844Header(parent, header); err != nil {
 			return err
 		}
+		if *header.BlobGasUsed > 0 { // VerifyEIP4844Header ensures BlobGasUsed is non-nil
+			return fmt.Errorf("blobs not enabled on avalanche networks: used %d blob gas, expected 0", *header.BlobGasUsed)
+		}
 	}
 	return nil
 }

core/state_processor_test.go

@@ -117,7 +117,8 @@ func TestStateProcessorErrors(t *testing.T) {
 				},
 				GasLimit: params.CortinaGasLimit,
 			}
-			blockchain, _  = NewBlockChain(db, DefaultCacheConfig, gspec, dummy.NewCoinbaseFaker(), vm.Config{}, common.Hash{}, false)
+			// FullFaker used to skip header verification that enforces no blobs.
+			blockchain, _  = NewBlockChain(db, DefaultCacheConfig, gspec, dummy.NewFullFaker(), vm.Config{}, common.Hash{}, false)
 			tooBigInitCode = [params.MaxInitCodeSize + 1]byte{}
 		)
 
@@ -236,7 +237,8 @@ func TestStateProcessorErrors(t *testing.T) {
 				want: "could not apply tx 0 [0x6c11015985ce82db691d7b2d017acda296db88b811c3c60dc71449c76256c716]: max fee per gas less than block base fee: address 0x71562b71999873DB5b286dF957af199Ec94617F7, maxFeePerGas: 1, baseFee: 225000000000",
 			},
 		} {
-			block := GenerateBadBlock(gspec.ToBlock(), dummy.NewCoinbaseFaker(), tt.txs, gspec.Config)
+			// FullFaker used to skip header verification that enforces no blobs.
+			block := GenerateBadBlock(gspec.ToBlock(), dummy.NewFullFaker(), tt.txs, gspec.Config)
 			_, err := blockchain.InsertChain(types.Blocks{block})
 			if err == nil {
 				t.Fatal("block imported without errors")

internal/ethapi/api_test.go

@@ -1436,7 +1436,8 @@ func setupReceiptBackend(t *testing.T, genBlocks int) (*testBackend, []common.Ha
 	// Set the terminal total difficulty in the config
 	// genesis.Config.TerminalTotalDifficulty = big.NewInt(0)
 	// genesis.Config.TerminalTotalDifficultyPassed = true
-	backend := newTestBackend(t, genBlocks, genesis, dummy.NewCoinbaseFaker(), func(i int, b *core.BlockGen) {
+	// FullFaker used to skip header verification that enforces no blobs.
+	backend := newTestBackend(t, genBlocks, genesis, dummy.NewFullFaker(), func(i int, b *core.BlockGen) {
 		var (
 			tx  *types.Transaction
 			err error

plugin/evm/block_verification.go

@@ -287,6 +287,11 @@ func (v blockValidator) SyntacticVerify(b *Block, rules params.Rules) error {
 		case *ethHeader.ParentBeaconRoot != (common.Hash{}):
 			return fmt.Errorf("invalid parentBeaconRoot: have %x, expected empty hash", ethHeader.ParentBeaconRoot)
 		}
+		if ethHeader.BlobGasUsed == nil {
+			return fmt.Errorf("blob gas used must not be nil in Cancun")
+		} else if *ethHeader.BlobGasUsed > 0 {
+			return fmt.Errorf("blobs not enabled on avalanche networks: used %d blob gas, expected 0", *ethHeader.BlobGasUsed)
+		}
 	}
 	return nil
 }

plugin/evm/vm_test.go

@@ -4090,6 +4090,39 @@ func TestParentBeaconRootBlock(t *testing.T) {
 	}
 }
 
+func TestNoBlobsAllowed(t *testing.T) {
+	require := require.New(t)
+	importAmount := uint64(1000000000)
+	issuer, vm, _, _, _ := GenesisVMWithUTXOs(t, true, genesisJSONCancun, "", "", map[ids.ShortID]uint64{
+		testShortIDAddrs[0]: importAmount,
+	})
+	defer func() { require.NoError(vm.Shutdown(context.Background())) }()
+
+	// Build a valid block in Cancun
+	importTx, err := vm.newImportTx(vm.ctx.XChainID, testEthAddrs[0], initialBaseFee, []*secp256k1.PrivateKey{testKeys[0]})
+	require.NoError(err)
+	require.NoError(vm.mempool.AddLocalTx(importTx))
+	<-issuer
+	blk, err := vm.BuildBlock(context.Background())
+	require.NoError(err)
+
+	// Modify the block to have a non-zero blob gas
+	ethBlock := blk.(*chain.BlockWrapper).Block.(*Block).ethBlock
+	header := types.CopyHeader(ethBlock.Header())
+	blobGasUsed := uint64(params.BlobTxBlobGasPerBlob)
+	header.BlobGasUsed = &blobGasUsed
+	modifiedEthBlock := types.NewBlockWithExtData(
+		header, nil, nil, nil, new(trie.Trie), ethBlock.ExtData(), false)
+	modifiedBlock, err := vm.newBlock(modifiedEthBlock)
+	require.NoError(err)
+
+	// Verification should fail
+	_, err = vm.ParseBlock(context.Background(), modifiedBlock.Bytes())
+	require.ErrorContains(err, "blobs not enabled on avalanche networks")
+	err = modifiedBlock.Verify(context.Background())
+	require.ErrorContains(err, "blobs not enabled on avalanche networks")
+}
+
 func TestMinFeeSetAtEUpgrade(t *testing.T) {
 	require := require.New(t)
 	now := time.Now()