[EVM] adding commitment over state updates

fvm/evm/emulator/emulator.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/holiman/uint256"
 	"github.com/onflow/atree"
+	"github.com/onflow/crypto/hash"
 	gethCommon "github.com/onflow/go-ethereum/common"
 	gethCore "github.com/onflow/go-ethereum/core"
 	gethTracing "github.com/onflow/go-ethereum/core/tracing"
@@ -178,7 +179,8 @@ func (bl *BlockView) RunTransaction(
 	}
 
 	// all commit errors (StateDB errors) has to be returned
-	if err := proc.commit(true); err != nil {
+	res.StateChangeCommitment, err = proc.commit(true)
+	if err != nil {
 		return nil, err
 	}
 
@@ -224,7 +226,8 @@ func (bl *BlockView) BatchRunTransactions(txs []*gethTypes.Transaction) ([]*type
 		}
 
 		// all commit errors (StateDB errors) has to be returned
-		if err := proc.commit(false); err != nil {
+		res.StateChangeCommitment, err = proc.commit(false)
+		if err != nil {
 			return nil, err
 		}
 
@@ -332,18 +335,18 @@ type procedure struct {
 }
 
 // commit commits the changes to the state (with optional finalization)
-func (proc *procedure) commit(finalize bool) error {
-	err := proc.state.Commit(finalize)
+func (proc *procedure) commit(finalize bool) (hash.Hash, error) {
+	stateUpdateCommitment, err := proc.state.Commit(finalize)
 	if err != nil {
 		// if known types (state errors) don't do anything and return
 		if types.IsAFatalError(err) || types.IsAStateError(err) || types.IsABackendError(err) {
-			return err
+			return stateUpdateCommitment, err
 		}
 
 		// else is a new fatal error
-		return types.NewFatalError(err)
+		return stateUpdateCommitment, types.NewFatalError(err)
 	}
-	return nil
+	return stateUpdateCommitment, nil
 }
 
 func (proc *procedure) mintTo(
@@ -386,7 +389,8 @@ func (proc *procedure) mintTo(
 	}
 
 	// commit and finalize the state and return any stateDB error
-	return res, proc.commit(true)
+	res.StateChangeCommitment, err = proc.commit(true)
+	return res, err
 }
 
 func (proc *procedure) withdrawFrom(
@@ -432,7 +436,8 @@ func (proc *procedure) withdrawFrom(
 	proc.state.SubBalance(bridge, value, gethTracing.BalanceIncreaseWithdrawal)
 
 	// commit and finalize the state and return any stateDB error
-	return res, proc.commit(true)
+	res.StateChangeCommitment, err = proc.commit(true)
+	return res, err
 }
 
 // deployAt deploys a contract at the given target address
@@ -574,7 +579,8 @@ func (proc *procedure) deployAt(
 	res.CumulativeGasUsed = proc.config.BlockTotalGasUsedSoFar + res.GasConsumed
 
 	proc.state.SetCode(addr, ret)
-	return res, proc.commit(true)
+	res.StateChangeCommitment, err = proc.commit(true)
+	return res, err
 }
 
 func (proc *procedure) runDirect(
@@ -590,7 +596,8 @@ func (proc *procedure) runDirect(
 		return nil, err
 	}
 	// commit and finalize the state and return any stateDB error
-	return res, proc.commit(true)
+	res.StateChangeCommitment, err = proc.commit(true)
+	return res, err
 }
 
 // run runs a geth core.message and returns the

fvm/evm/emulator/state/stateDB.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/holiman/uint256"
 	"github.com/onflow/atree"
+	"github.com/onflow/crypto/hash"
 	gethCommon "github.com/onflow/go-ethereum/common"
 	gethStateless "github.com/onflow/go-ethereum/core/stateless"
 	gethTracing "github.com/onflow/go-ethereum/core/tracing"
@@ -347,10 +348,10 @@ func (db *StateDB) Preimages() map[gethCommon.Hash][]byte {
 }
 
 // Commit commits state changes back to the underlying
-func (db *StateDB) Commit(finalize bool) error {
-	// return error if any has been acumulated
+func (db *StateDB) Commit(finalize bool) (hash.Hash, error) {
+	// return error if any has been accumulated
 	if db.cachedError != nil {
-		return wrapError(db.cachedError)
+		return nil, wrapError(db.cachedError)
 	}
 
 	var err error
@@ -378,43 +379,61 @@ func (db *StateDB) Commit(finalize bool) error {
 			return bytes.Compare(sortedAddresses[i][:], sortedAddresses[j][:]) < 0
 		})
 
+	updateCommitter := NewUpdateCommitter()
 	// update accounts
 	for _, addr := range sortedAddresses {
 		deleted := false
 		// first we need to delete accounts
 		if db.HasSelfDestructed(addr) {
 			err = db.baseView.DeleteAccount(addr)
 			if err != nil {
-				return wrapError(err)
+				return nil, wrapError(err)
+			}
+			err = updateCommitter.DeleteAccount(addr)
+			if err != nil {
+				return nil, wrapError(err)
 			}
 			deleted = true
 		}
 		if deleted {
 			continue
 		}
+
+		bal := db.GetBalance(addr)
+		nonce := db.GetNonce(addr)
+		code := db.GetCode(addr)
+		codeHash := db.GetCodeHash(addr)
 		// create new accounts
 		if db.IsCreated(addr) {
 			err = db.baseView.CreateAccount(
 				addr,
-				db.GetBalance(addr),
-				db.GetNonce(addr),
-				db.GetCode(addr),
-				db.GetCodeHash(addr),
+				bal,
+				nonce,
+				code,
+				codeHash,
 			)
 			if err != nil {
-				return wrapError(err)
+				return nil, wrapError(err)
+			}
+			err = updateCommitter.CreateAccount(addr, bal, nonce, codeHash)
+			if err != nil {
+				return nil, wrapError(err)
 			}
 			continue
 		}
 		err = db.baseView.UpdateAccount(
 			addr,
-			db.GetBalance(addr),
-			db.GetNonce(addr),
-			db.GetCode(addr),
-			db.GetCodeHash(addr),
+			bal,
+			nonce,
+			code,
+			codeHash,
 		)
 		if err != nil {
-			return wrapError(err)
+			return nil, wrapError(err)
+		}
+		err = updateCommitter.UpdateAccount(addr, bal, nonce, codeHash)
+		if err != nil {
+			return nil, wrapError(err)
 		}
 	}
 
@@ -437,20 +456,29 @@ func (db *StateDB) Commit(finalize bool) error {
 		if db.HasSelfDestructed(sk.Address) {
 			continue
 		}
+		val := db.GetState(sk.Address, sk.Key)
 		err = db.baseView.UpdateSlot(
 			sk,
-			db.GetState(sk.Address, sk.Key),
+			val,
 		)
 		if err != nil {
-			return wrapError(err)
+			return nil, wrapError(err)
+		}
+		err = updateCommitter.UpdateSlot(sk.Address, sk.Key, val)
+		if err != nil {
+			return nil, wrapError(err)
 		}
 	}
 
 	// don't purge views yet, people might call the logs etc
+	updateCommit := updateCommitter.Commitment()
 	if finalize {
-		return db.Finalize()
+		err := db.Finalize()
+		if err != nil {
+			return nil, err
+		}
 	}
-	return nil
+	return updateCommit, nil
 }
 
 // Finalize flushes all the changes

fvm/evm/emulator/state/stateDB_test.go

@@ -88,8 +88,9 @@ func TestStateDB(t *testing.T) {
 		ret = db.GetCommittedState(addr1, key1)
 		require.Equal(t, gethCommon.Hash{}, ret)
 
-		err = db.Commit(true)
+		commit, err := db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 
 		ret = db.GetCommittedState(addr1, key1)
 		require.Equal(t, value1, ret)
@@ -272,10 +273,10 @@ func TestStateDB(t *testing.T) {
 		require.NoError(t, err)
 
 		db.CreateAccount(testutils.RandomCommonAddress(t))
-
-		err = db.Commit(true)
+		commit, err := db.Commit(true)
 		// ret := db.Error()
 		require.Error(t, err)
+		require.Empty(t, commit)
 		// check wrapping
 		require.True(t, types.IsAStateError(err))
 	})
@@ -297,9 +298,10 @@ func TestStateDB(t *testing.T) {
 
 		db.CreateAccount(testutils.RandomCommonAddress(t))
 
-		err = db.Commit(true)
+		commit, err := db.Commit(true)
 		// ret := db.Error()
 		require.Error(t, err)
+		require.Empty(t, commit)
 		// check wrapping
 		require.True(t, types.IsAFatalError(err))
 	})
@@ -321,17 +323,19 @@ func TestStateDB(t *testing.T) {
 		// accounts without slots
 		db.CreateAccount(addr1)
 		require.NoError(t, db.Error())
-		err = db.Commit(true)
+		commit, err := db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 
 		root = db.GetStorageRoot(addr1)
 		require.NoError(t, db.Error())
 		require.Equal(t, gethTypes.EmptyRootHash, root)
 
 		db.AddBalance(addr1, uint256.NewInt(100), tracing.BalanceChangeTouchAccount)
 		require.NoError(t, db.Error())
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 
 		root = db.GetStorageRoot(addr1)
 		require.NoError(t, db.Error())
@@ -344,8 +348,9 @@ func TestStateDB(t *testing.T) {
 		require.NoError(t, db.Error())
 		db.SetState(addr1, key, value)
 		require.NoError(t, db.Error())
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 
 		root = db.GetStorageRoot(addr1)
 		require.NoError(t, db.Error())
@@ -367,8 +372,9 @@ func TestStateDB(t *testing.T) {
 		db.SetCode(addr1, code1)
 		db.AddBalance(addr1, balance1, tracing.BalanceChangeTransfer)
 		require.NoError(t, db.Error())
-		err = db.Commit(true)
+		commit, err := db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 		// renew db
 		db, err = state.NewStateDB(ledger, rootAddr)
 		require.NoError(t, err)
@@ -388,8 +394,9 @@ func TestStateDB(t *testing.T) {
 		db.AddBalance(addr2, balance2, tracing.BalanceChangeTransfer)
 		require.NoError(t, db.Error())
 		// commit and renew db
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 		db, err = state.NewStateDB(ledger, rootAddr)
 		require.NoError(t, err)
 		// call self destruct should not work
@@ -400,8 +407,9 @@ func TestStateDB(t *testing.T) {
 		require.Empty(t, db.GetCode(addr2))
 		require.NoError(t, db.Error())
 		// commit and renew db
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 		db, err = state.NewStateDB(ledger, rootAddr)
 		require.NoError(t, err)
 		// set code and call contract creation
@@ -411,8 +419,9 @@ func TestStateDB(t *testing.T) {
 		// now calling selfdestruct should do the job
 		db.Selfdestruct6780(addr2)
 		require.NoError(t, db.Error())
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 		db, err = state.NewStateDB(ledger, rootAddr)
 		require.NoError(t, err)
 		// now query
@@ -438,8 +447,9 @@ func TestStateDB(t *testing.T) {
 		db.Selfdestruct6780(addr3)
 		require.NoError(t, db.Error())
 		// commit changes
-		err = db.Commit(true)
+		commit, err = db.Commit(true)
 		require.NoError(t, err)
+		require.NotEmpty(t, commit)
 		// renew db
 		db, err = state.NewStateDB(ledger, rootAddr)
 		require.NoError(t, err)

fvm/evm/emulator/state/state_growth_test.go

@@ -64,7 +64,7 @@ func (s *storageTest) run(runner func(state types.StateDB)) error {
 
 	runner(state)
 
-	err = state.Commit(true)
+	_, err = state.Commit(true)
 	if err != nil {
 		return err
 	}