imp(evm): stateless custom precompiles (#1272)

* release: v0.17.0 changelog (#1153)

* release: v0.17.0 changelog

* rm newline

* update link

* imp(evm): EVM interface

* fixes

* fix lint

* fix lint pt 2

* initial wiring for stateful contracts

* Apply suggestions from code review

Co-authored-by: Vladislav Varadinov <vladislav.varadinov@gmail.com>

* changelog

* comments from review

* lint

Co-authored-by: Vladislav Varadinov <vladislav.varadinov@gmail.com>

x/evm/keeper/keeper.go

@@ -19,6 +19,7 @@ import (
 	ethermint "github.com/evmos/ethermint/types"
 	"github.com/evmos/ethermint/x/evm/statedb"
 	"github.com/evmos/ethermint/x/evm/types"
+	evm "github.com/evmos/ethermint/x/evm/vm"
 )
 
 // Keeper grants access to the EVM module state and implements the go-ethereum StateDB interface.
@@ -54,14 +55,25 @@ type Keeper struct {
 
 	// EVM Hooks for tx post-processing
 	hooks types.EvmHooks
+
+	// custom stateless precompiled smart contracts
+	customPrecompiles evm.PrecompiledContracts
+
+	// evm constructor function
+	evmConstructor evm.Constructor
 }
 
 // NewKeeper generates new evm module keeper
 func NewKeeper(
 	cdc codec.BinaryCodec,
-	storeKey, transientKey storetypes.StoreKey, paramSpace paramtypes.Subspace,
-	ak types.AccountKeeper, bankKeeper types.BankKeeper, sk types.StakingKeeper,
+	storeKey, transientKey storetypes.StoreKey,
+	paramSpace paramtypes.Subspace,
+	ak types.AccountKeeper,
+	bankKeeper types.BankKeeper,
+	sk types.StakingKeeper,
 	fmk types.FeeMarketKeeper,
+	customPrecompiles evm.PrecompiledContracts,
+	evmConstructor evm.Constructor,
 	tracer string,
 ) *Keeper {
 	// ensure evm module account is set
@@ -76,15 +88,17 @@ func NewKeeper(
 
 	// NOTE: we pass in the parameter space to the CommitStateDB in order to use custom denominations for the EVM operations
 	return &Keeper{
-		cdc:             cdc,
-		paramSpace:      paramSpace,
-		accountKeeper:   ak,
-		bankKeeper:      bankKeeper,
-		stakingKeeper:   sk,
-		feeMarketKeeper: fmk,
-		storeKey:        storeKey,
-		transientKey:    transientKey,
-		tracer:          tracer,
+		cdc:               cdc,
+		paramSpace:        paramSpace,
+		accountKeeper:     ak,
+		bankKeeper:        bankKeeper,
+		stakingKeeper:     sk,
+		feeMarketKeeper:   fmk,
+		storeKey:          storeKey,
+		transientKey:      transientKey,
+		customPrecompiles: customPrecompiles,
+		evmConstructor:    evmConstructor,
+		tracer:            tracer,
 	}
 }
 

x/evm/keeper/state_transition.go

@@ -16,6 +16,7 @@ import (
 	ethermint "github.com/evmos/ethermint/types"
 	"github.com/evmos/ethermint/x/evm/statedb"
 	"github.com/evmos/ethermint/x/evm/types"
+	evm "github.com/evmos/ethermint/x/evm/vm"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -77,7 +78,7 @@ func (k *Keeper) NewEVM(
 	cfg *types.EVMConfig,
 	tracer vm.EVMLogger,
 	stateDB vm.StateDB,
-) *vm.EVM {
+) evm.EVM {
 	blockCtx := vm.BlockContext{
 		CanTransfer: core.CanTransfer,
 		Transfer:    core.Transfer,
@@ -95,7 +96,7 @@ func (k *Keeper) NewEVM(
 		tracer = k.Tracer(ctx, msg, cfg.ChainConfig)
 	}
 	vmConfig := k.VMConfig(ctx, msg, cfg, tracer)
-	return vm.NewEVM(blockCtx, txCtx, stateDB, cfg.ChainConfig, vmConfig)
+	return k.evmConstructor(blockCtx, txCtx, stateDB, cfg.ChainConfig, vmConfig, k.customPrecompiles)
 }
 
 // VMConfig creates an EVM configuration from the debug setting and the extra EIPs enabled on the
@@ -366,17 +367,19 @@ func (k *Keeper) ApplyMessageWithConfig(ctx sdk.Context,
 	evm := k.NewEVM(ctx, msg, cfg, tracer, stateDB)
 
 	leftoverGas := msg.Gas()
+
 	// Allow the tracer captures the tx level events, mainly the gas consumption.
-	if evm.Config.Debug {
-		evm.Config.Tracer.CaptureTxStart(leftoverGas)
+	vmCfg := evm.Config()
+	if vmCfg.Debug {
+		vmCfg.Tracer.CaptureTxStart(leftoverGas)
 		defer func() {
-			evm.Config.Tracer.CaptureTxEnd(leftoverGas)
+			vmCfg.Tracer.CaptureTxEnd(leftoverGas)
 		}()
 	}
 
 	sender := vm.AccountRef(msg.From())
 	contractCreation := msg.To() == nil
-	isLondon := cfg.ChainConfig.IsLondon(evm.Context.BlockNumber)
+	isLondon := cfg.ChainConfig.IsLondon(evm.Context().BlockNumber)
 
 	intrinsicGas, err := k.GetEthIntrinsicGas(ctx, msg, cfg.ChainConfig, contractCreation)
 	if err != nil {
@@ -394,7 +397,7 @@ func (k *Keeper) ApplyMessageWithConfig(ctx sdk.Context,
 	// access list preparation is moved from ante handler to here, because it's needed when `ApplyMessage` is called
 	// under contexts where ante handlers are not run, for example `eth_call` and `eth_estimateGas`.
 	if rules := cfg.ChainConfig.Rules(big.NewInt(ctx.BlockHeight()), cfg.ChainConfig.MergeNetsplitBlock != nil); rules.IsBerlin {
-		stateDB.PrepareAccessList(msg.From(), msg.To(), vm.ActivePrecompiles(rules), msg.AccessList())
+		stateDB.PrepareAccessList(msg.From(), msg.To(), evm.ActivePrecompiles(rules), msg.AccessList())
 	}
 
 	if contractCreation {