core/vm: set basefee to 0 internally on eth_call (#28470)

* core/vm: set basefee to 0 internally on eth_call

* core: nicer 0-basefee, make it work for blob fees too

* internal/ethapi: make tests a bit more complex

* core: fix blob fee checker

* core: make code a bit more readable

* core: fix some test error strings

* core/vm: Get rid of weird comment

* core: dict wrong typo

core/vm/evm.go

@@ -72,8 +72,8 @@ type BlockContext struct {
 	BlockNumber *big.Int       // Provides information for NUMBER
 	Time        uint64         // Provides information for TIME
 	Difficulty  *big.Int       // Provides information for DIFFICULTY
-	BaseFee     *big.Int       // Provides information for BASEFEE
-	BlobBaseFee *big.Int       // Provides information for BLOBBASEFEE
+	BaseFee     *big.Int       // Provides information for BASEFEE (0 if vm runs with NoBaseFee flag and 0 gas price)
+	BlobBaseFee *big.Int       // Provides information for BLOBBASEFEE (0 if vm runs with NoBaseFee flag and 0 blob gas price)
 	Random      *common.Hash   // Provides information for PREVRANDAO
 }
 
@@ -82,8 +82,9 @@ type BlockContext struct {
 type TxContext struct {
 	// Message information
 	Origin     common.Address // Provides information for ORIGIN
-	GasPrice   *big.Int       // Provides information for GASPRICE
+	GasPrice   *big.Int       // Provides information for GASPRICE (and is used to zero the basefee if NoBaseFee is set)
 	BlobHashes []common.Hash  // Provides information for BLOBHASH
+	BlobFeeCap *big.Int       // Is used to zero the blobbasefee if NoBaseFee is set
 }
 
 // EVM is the Ethereum Virtual Machine base object and provides
@@ -125,6 +126,17 @@ type EVM struct {
 // NewEVM returns a new EVM. The returned EVM is not thread safe and should
 // only ever be used *once*.
 func NewEVM(blockCtx BlockContext, txCtx TxContext, statedb StateDB, chainConfig *params.ChainConfig, config Config) *EVM {
+	// If basefee tracking is disabled (eth_call, eth_estimateGas, etc), and no
+	// gas prices were specified, lower the basefee to 0 to avoid breaking EVM
+	// invariants (basefee < feecap)
+	if config.NoBaseFee {
+		if txCtx.GasPrice.BitLen() == 0 {
+			blockCtx.BaseFee = new(big.Int)
+		}
+		if txCtx.BlobFeeCap != nil && txCtx.BlobFeeCap.BitLen() == 0 {
+			blockCtx.BlobBaseFee = new(big.Int)
+		}
+	}
 	evm := &EVM{
 		Context:     blockCtx,
 		TxContext:   txCtx,
@@ -160,14 +172,6 @@ func (evm *EVM) Interpreter() *EVMInterpreter {
 	return evm.interpreter
 }
 
-// SetBlockContext updates the block context of the EVM.
-func (evm *EVM) SetBlockContext(blockCtx BlockContext) {
-	evm.Context = blockCtx
-	num := blockCtx.BlockNumber
-	timestamp := blockCtx.Time
-	evm.chainRules = evm.chainConfig.Rules(num, blockCtx.Random != nil, timestamp)
-}
-
 // Call executes the contract associated with the addr with the given input as
 // parameters. It also handles any necessary value transfer required and takes
 // the necessary steps to create accounts and reverses the state in case of an

core/vm/runtime/env.go

@@ -26,6 +26,7 @@ func NewEnv(cfg *Config) *vm.EVM {
 		Origin:     cfg.Origin,
 		GasPrice:   cfg.GasPrice,
 		BlobHashes: cfg.BlobHashes,
+		BlobFeeCap: cfg.BlobFeeCap,
 	}
 	blockContext := vm.BlockContext{
 		CanTransfer: core.CanTransfer,

core/vm/runtime/runtime.go

@@ -46,6 +46,7 @@ type Config struct {
 	BaseFee     *big.Int
 	BlobBaseFee *big.Int
 	BlobHashes  []common.Hash
+	BlobFeeCap  *big.Int
 	Random      *common.Hash
 
 	State     *state.StateDB
@@ -97,7 +98,7 @@ func setDefaults(cfg *Config) {
 		cfg.BaseFee = big.NewInt(params.InitialBaseFee)
 	}
 	if cfg.BlobBaseFee == nil {
-		cfg.BlobBaseFee = new(big.Int)
+		cfg.BlobBaseFee = big.NewInt(params.BlobTxMinBlobGasprice)
 	}
 }