consensus, core/typer: add 4844 excessDataGas to header, tie it to Cancun

consensus/beacon/consensus.go

@@ -263,11 +263,19 @@ func (beacon *Beacon) verifyHeader(chain consensus.ChainHeaderReader, header, pa
 	// Verify existence / non-existence of withdrawalsHash.
 	shanghai := chain.Config().IsShanghai(header.Time)
 	if shanghai && header.WithdrawalsHash == nil {
-		return fmt.Errorf("missing withdrawalsHash")
+		return errors.New("missing withdrawalsHash")
 	}
 	if !shanghai && header.WithdrawalsHash != nil {
 		return fmt.Errorf("invalid withdrawalsHash: have %x, expected nil", header.WithdrawalsHash)
 	}
+	// Verify the existence / non-existence of excessDataGas
+	cancun := chain.Config().IsCancun(header.Time)
+	if cancun && header.ExcessDataGas == nil {
+		return errors.New("missing excessDataGas")
+	}
+	if !cancun && header.ExcessDataGas != nil {
+		return fmt.Errorf("invalid excessDataGas: have %d, expected nil", header.ExcessDataGas)
+	}
 	return nil
 }
 

consensus/clique/clique.go

@@ -301,6 +301,9 @@ func (c *Clique) verifyHeader(chain consensus.ChainHeaderReader, header *types.H
 	if chain.Config().IsShanghai(header.Time) {
 		return fmt.Errorf("clique does not support shanghai fork")
 	}
+	if chain.Config().IsCancun(header.Time) {
+		return fmt.Errorf("clique does not support cancun fork")
+	}
 	// If all checks passed, validate any special fields for hard forks
 	if err := misc.VerifyForkHashes(chain.Config(), header, false); err != nil {
 		return err

consensus/ethash/consensus.go

@@ -313,6 +313,9 @@ func (ethash *Ethash) verifyHeader(chain consensus.ChainHeaderReader, header, pa
 	if chain.Config().IsShanghai(header.Time) {
 		return fmt.Errorf("ethash does not support shanghai fork")
 	}
+	if chain.Config().IsCancun(header.Time) {
+		return fmt.Errorf("ethash does not support cancun fork")
+	}
 	// Verify the engine specific seal securing the block
 	if seal {
 		if err := ethash.verifySeal(chain, header, false); err != nil {

core/types/block.go

@@ -85,6 +85,9 @@ type Header struct {
 	// WithdrawalsHash was added by EIP-4895 and is ignored in legacy headers.
 	WithdrawalsHash *common.Hash `json:"withdrawalsRoot" rlp:"optional"`
 
+	// ExcessDataGas was added by EIP-4844 and is ignored in legacy headers.
+	ExcessDataGas *big.Int `json:"excessDataGas" rlp:"optional"`
+
 	/*
 		TODO (MariusVanDerWijden) Add this field once needed
 		// Random was added during the merge and contains the BeaconState randomness