core: check if sender is EOA (#23303)

This adds a check to verify that a sender-account does not have code, which means that the codehash is either `emptyCodeHash` _OR_ not present. The latter occurs IFF the sender did not previously exist, a situation which can only occur with zero cost gasprices.

core/error.go

@@ -87,4 +87,7 @@ var (
 	// ErrFeeCapTooLow is returned if the transaction fee cap is less than the
 	// the base fee of the block.
 	ErrFeeCapTooLow = errors.New("max fee per gas less than block base fee")
+
+	// ErrSenderNoEOA is returned if the sender of a transaction is a contract.
+	ErrSenderNoEOA = errors.New("sender not an eoa")
 )

core/state_processor_test.go

@@ -195,7 +195,7 @@ func TestStateProcessorErrors(t *testing.T) {
 		}
 	}
 
-	// One final error is ErrTxTypeNotSupported. For this, we need an older chain
+	// ErrTxTypeNotSupported, For this, we need an older chain
 	{
 		var (
 			db    = rawdb.NewMemoryDatabase()
@@ -244,6 +244,46 @@ func TestStateProcessorErrors(t *testing.T) {
 			}
 		}
 	}
+
+	// ErrSenderNoEOA, for this we need the sender to have contract code
+	{
+		var (
+			db    = rawdb.NewMemoryDatabase()
+			gspec = &Genesis{
+				Config: config,
+				Alloc: GenesisAlloc{
+					common.HexToAddress("0x71562b71999873DB5b286dF957af199Ec94617F7"): GenesisAccount{
+						Balance: big.NewInt(1000000000000000000), // 1 ether
+						Nonce:   0,
+						Code:    common.FromHex("0xB0B0FACE"),
+					},
+				},
+			}
+			genesis       = gspec.MustCommit(db)
+			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, nil)
+		)
+		defer blockchain.Stop()
+		for i, tt := range []struct {
+			txs  []*types.Transaction
+			want string
+		}{
+			{ // ErrSenderNoEOA
+				txs: []*types.Transaction{
+					mkDynamicTx(0, common.Address{}, params.TxGas-1000, big.NewInt(0), big.NewInt(0)),
+				},
+				want: "could not apply tx 0 [0x88626ac0d53cb65308f2416103c62bb1f18b805573d4f96a3640bbbfff13c14f]: sender not an eoa: address 0x71562b71999873DB5b286dF957af199Ec94617F7, codehash: 0x9280914443471259d4570a8661015ae4a5b80186dbc619658fb494bebc3da3d1",
+			},
+		} {
+			block := GenerateBadBlock(genesis, ethash.NewFaker(), tt.txs, gspec.Config)
+			_, err := blockchain.InsertChain(types.Blocks{block})
+			if err == nil {
+				t.Fatal("block imported without errors")
+			}
+			if have, want := err.Error(), tt.want; have != want {
+				t.Errorf("test %d:\nhave \"%v\"\nwant \"%v\"\n", i, have, want)
+			}
+		}
+	}
 }
 
 // GenerateBadBlock constructs a "block" which contains the transactions. The transactions are not expected to be

core/state_transition.go

@@ -25,9 +25,12 @@ import (
 	cmath "github.com/ethereum/go-ethereum/common/math"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/params"
 )
 
+var emptyCodeHash = crypto.Keccak256Hash(nil)
+
 /*
 The State Transitioning Model
 
@@ -220,6 +223,11 @@ func (st *StateTransition) preCheck() error {
 				st.msg.From().Hex(), msgNonce, stNonce)
 		}
 	}
+	// Make sure the sender is an EOA
+	if codeHash := st.state.GetCodeHash(st.msg.From()); codeHash != emptyCodeHash && codeHash != (common.Hash{}) {
+		return fmt.Errorf("%w: address %v, codehash: %s", ErrSenderNoEOA,
+			st.msg.From().Hex(), codeHash)
+	}
 	// Make sure that transaction gasFeeCap is greater than the baseFee (post london)
 	if st.evm.ChainConfig().IsLondon(st.evm.Context.BlockNumber) {
 		// Skip the checks if gas fields are zero and baseFee was explicitly disabled (eth_call)