package keeper import ( "bytes" "fmt" "math/big" "github.com/ethereum/go-ethereum/common" ethtypes "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/core/vm" "github.com/ethereum/go-ethereum/crypto" "github.com/cosmos/cosmos-sdk/store/prefix" sdk "github.com/cosmos/cosmos-sdk/types" ethermint "github.com/tharsis/ethermint/types" "github.com/tharsis/ethermint/x/evm/types" ) var _ vm.StateDB = &Keeper{} // ---------------------------------------------------------------------------- // Account // ---------------------------------------------------------------------------- // CreateAccount creates a new EthAccount instance from the provided address and // sets the value to store. func (k *Keeper) CreateAccount(addr common.Address) { cosmosAddr := sdk.AccAddress(addr.Bytes()) account := k.accountKeeper.GetAccount(k.ctx, cosmosAddr) log := "" if account == nil { log = "account created" } else { log = "account overwritten" k.ResetAccount(addr) } account = k.accountKeeper.NewAccountWithAddress(k.ctx, cosmosAddr) k.accountKeeper.SetAccount(k.ctx, account) k.Logger(k.ctx).Debug( log, "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) } // ---------------------------------------------------------------------------- // Balance // ---------------------------------------------------------------------------- // AddBalance calls CommitStateDB.AddBalance using the passed in context func (k *Keeper) AddBalance(addr common.Address, amount *big.Int) { if amount.Sign() != 1 { k.Logger(k.ctx).Debug( "ignored non-positive amount addition", "ethereum-address", addr.Hex(), "amount", amount.Int64(), ) return } cosmosAddr := sdk.AccAddress(addr.Bytes()) params := k.GetParams(k.ctx) coins := sdk.Coins{sdk.NewCoin(params.EvmDenom, sdk.NewIntFromBigInt(amount))} if err := k.bankKeeper.MintCoins(k.ctx, types.ModuleName, coins); err != nil { k.Logger(k.ctx).Error( "failed to mint coins when adding balance", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) return } if err := k.bankKeeper.SendCoinsFromModuleToAccount(k.ctx, types.ModuleName, cosmosAddr, coins); err != nil { k.Logger(k.ctx).Error( "failed to send from module to account when adding balance", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) return } k.Logger(k.ctx).Debug( "balance addition", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) } // SubBalance calls CommitStateDB.SubBalance using the passed in context func (k *Keeper) SubBalance(addr common.Address, amount *big.Int) { if amount.Sign() != 1 { k.Logger(k.ctx).Debug( "ignored non-positive amount addition", "ethereum-address", addr.Hex(), "amount", amount.Int64(), ) return } cosmosAddr := sdk.AccAddress(addr.Bytes()) params := k.GetParams(k.ctx) coins := sdk.Coins{sdk.NewCoin(params.EvmDenom, sdk.NewIntFromBigInt(amount))} if err := k.bankKeeper.SendCoinsFromAccountToModule(k.ctx, cosmosAddr, types.ModuleName, coins); err != nil { k.Logger(k.ctx).Error( "failed to send from account to module when subtracting balance", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) return } if err := k.bankKeeper.BurnCoins(k.ctx, types.ModuleName, coins); err != nil { k.Logger(k.ctx).Error( "failed to burn coins when subtracting balance", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) return } k.Logger(k.ctx).Debug( "balance subtraction", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) } // GetBalance calls CommitStateDB.GetBalance using the passed in context func (k *Keeper) GetBalance(addr common.Address) *big.Int { cosmosAddr := sdk.AccAddress(addr.Bytes()) params := k.GetParams(k.ctx) balance := k.bankKeeper.GetBalance(k.ctx, cosmosAddr, params.EvmDenom) return balance.Amount.BigInt() } // ---------------------------------------------------------------------------- // Nonce // ---------------------------------------------------------------------------- // GetNonce calls CommitStateDB.GetNonce using the passed in context func (k *Keeper) GetNonce(addr common.Address) uint64 { cosmosAddr := sdk.AccAddress(addr.Bytes()) nonce, err := k.accountKeeper.GetSequence(k.ctx, cosmosAddr) if err != nil { k.Logger(k.ctx).Error( "account not found", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) } return nonce } // SetNonce sets the given nonce as the sequence of the address' account. If the // account doesn't exist, a new one will be created from the address. func (k *Keeper) SetNonce(addr common.Address, nonce uint64) { cosmosAddr := sdk.AccAddress(addr.Bytes()) account := k.accountKeeper.GetAccount(k.ctx, cosmosAddr) if account == nil { k.Logger(k.ctx).Debug( "account not found", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) // create address if it doesn't exist account = k.accountKeeper.NewAccountWithAddress(k.ctx, cosmosAddr) } if err := account.SetSequence(nonce); err != nil { k.Logger(k.ctx).Error( "failed to set nonce", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "nonce", nonce, "error", err, ) return } k.accountKeeper.SetAccount(k.ctx, account) k.Logger(k.ctx).Debug( "nonce set", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "nonce", nonce, ) } // ---------------------------------------------------------------------------- // Code // ---------------------------------------------------------------------------- // GetCodeHash calls CommitStateDB.GetCodeHash using the passed in context func (k *Keeper) GetCodeHash(addr common.Address) common.Hash { cosmosAddr := sdk.AccAddress(addr.Bytes()) account := k.accountKeeper.GetAccount(k.ctx, cosmosAddr) if account == nil { return common.BytesToHash(types.EmptyCodeHash) } ethAccount, isEthAccount := account.(*ethermint.EthAccount) if !isEthAccount { return common.BytesToHash(types.EmptyCodeHash) } return common.HexToHash(ethAccount.CodeHash) } // GetCode calls CommitStateDB.GetCode using the passed in context func (k *Keeper) GetCode(addr common.Address) []byte { hash := k.GetCodeHash(addr) if bytes.Equal(hash.Bytes(), common.BytesToHash(types.EmptyCodeHash).Bytes()) { return nil } store := prefix.NewStore(k.ctx.KVStore(k.storeKey), types.KeyPrefixCode) code := store.Get(hash.Bytes()) if len(code) == 0 { k.Logger(k.ctx).Debug( "code not found", "ethereum-address", addr.Hex(), "code-hash", hash.Hex(), ) } return code } // SetCode calls CommitStateDB.SetCode using the passed in context func (k *Keeper) SetCode(addr common.Address, code []byte) { if bytes.Equal(code, types.EmptyCodeHash) { k.Logger(k.ctx).Debug("passed in EmptyCodeHash, but expected empty code") } hash := crypto.Keccak256Hash(code) // update account code hash account := k.accountKeeper.GetAccount(k.ctx, addr.Bytes()) if account == nil { account = k.accountKeeper.NewAccountWithAddress(k.ctx, addr.Bytes()) k.accountKeeper.SetAccount(k.ctx, account) } ethAccount, isEthAccount := account.(*ethermint.EthAccount) if !isEthAccount { k.Logger(k.ctx).Error( "invalid account type", "ethereum-address", addr.Hex(), "code-hash", hash.Hex(), ) return } ethAccount.CodeHash = hash.Hex() k.accountKeeper.SetAccount(k.ctx, ethAccount) store := prefix.NewStore(k.ctx.KVStore(k.storeKey), types.KeyPrefixCode) action := "updated" // store or delete code if len(code) == 0 { store.Delete(hash.Bytes()) action = "deleted" } else { store.Set(hash.Bytes(), code) } k.Logger(k.ctx).Debug( fmt.Sprintf("code %s", action), "ethereum-address", addr.Hex(), "code-hash", hash.Hex(), ) } // GetCodeSize returns the size of the contract code associated with this object, // or zero if none. func (k *Keeper) GetCodeSize(addr common.Address) int { code := k.GetCode(addr) return len(code) } // ---------------------------------------------------------------------------- // Refund // ---------------------------------------------------------------------------- // NOTE: gas refunded needs to be tracked and stored in a separate variable in // order to add it subtract/add it from/to the gas used value after the EVM // execution has finalized. The refund value is cleared on every transaction and // at the end of every block. // AddRefund adds the given amount of gas to the refund cached value. func (k *Keeper) AddRefund(gas uint64) { refund := k.GetRefund() refund += gas store := k.ctx.TransientStore(k.transientKey) store.Set(types.KeyPrefixTransientRefund, sdk.Uint64ToBigEndian(refund)) } // SubRefund subtracts the given amount of gas from the refund value. This function // will panic if gas amount is greater than the stored refund. func (k *Keeper) SubRefund(gas uint64) { refund := k.GetRefund() if gas > refund { // TODO: (@fedekunze) set to 0?? Geth panics here panic("refund counter below zero") } refund -= gas store := k.ctx.TransientStore(k.transientKey) store.Set(types.KeyPrefixTransientRefund, sdk.Uint64ToBigEndian(refund)) } // GetRefund returns the amount of gas available for return after the tx execution // finalises. This value is reset to 0 on every transaction. func (k *Keeper) GetRefund() uint64 { store := k.ctx.TransientStore(k.transientKey) bz := store.Get(types.KeyPrefixTransientRefund) if len(bz) == 0 { return 0 } return sdk.BigEndianToUint64(bz) } // ---------------------------------------------------------------------------- // State // ---------------------------------------------------------------------------- // GetCommittedState returns the value set in store for the given key hash. If the key is not registered // this function returns the empty hash. func (k *Keeper) GetCommittedState(addr common.Address, hash common.Hash) common.Hash { store := prefix.NewStore(k.ctx.KVStore(k.storeKey), types.AddressStoragePrefix(addr)) key := types.KeyAddressStorage(addr, hash) value := store.Get(key.Bytes()) if len(value) == 0 { return common.Hash{} } return common.BytesToHash(value) } // GetState returns the committed state for the given key hash, as all changes are committed directly // to the KVStore. func (k *Keeper) GetState(addr common.Address, hash common.Hash) common.Hash { return k.GetCommittedState(addr, hash) } // SetState sets the given hashes (key, value) to the KVStore. If the value hash is empty, this // function deletes the key from the store. func (k *Keeper) SetState(addr common.Address, key, value common.Hash) { store := prefix.NewStore(k.ctx.KVStore(k.storeKey), types.AddressStoragePrefix(addr)) key = types.KeyAddressStorage(addr, key) action := "updated" if ethermint.IsEmptyHash(value.Hex()) { store.Delete(key.Bytes()) action = "deleted" } else { store.Set(key.Bytes(), value.Bytes()) } k.Logger(k.ctx).Debug( fmt.Sprintf("state %s", action), "ethereum-address", addr.Hex(), "key", key.Hex(), ) } // ---------------------------------------------------------------------------- // Suicide // ---------------------------------------------------------------------------- // Suicide marks the given account as suicided and clears the account balance of // the EVM tokens. func (k *Keeper) Suicide(addr common.Address) bool { prev := k.HasSuicided(addr) if prev { return true } cosmosAddr := sdk.AccAddress(addr.Bytes()) _, err := k.ClearBalance(cosmosAddr) if err != nil { k.Logger(k.ctx).Error( "failed to subtract balance on suicide", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), "error", err, ) return false } // TODO: (@fedekunze) do we also need to delete the storage state and the code? // Set a single byte to the transient store store := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientSuicided) store.Set(addr.Bytes(), []byte{1}) k.Logger(k.ctx).Debug( "account suicided", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) return true } // HasSuicided queries the transient store to check if the account has been marked as suicided in the // current block. Accounts that are suicided will be returned as non-nil during queries and "cleared" // after the block has been committed. func (k *Keeper) HasSuicided(addr common.Address) bool { store := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientSuicided) return store.Has(addr.Bytes()) } // ---------------------------------------------------------------------------- // Account Exist / Empty // ---------------------------------------------------------------------------- // Exist returns true if the given account exists in store or if it has been // marked as suicided in the transient store. func (k *Keeper) Exist(addr common.Address) bool { // return true if the account has suicided if k.HasSuicided(addr) { return true } cosmosAddr := sdk.AccAddress(addr.Bytes()) account := k.accountKeeper.GetAccount(k.ctx, cosmosAddr) return account != nil } // Empty returns true if the address meets the following conditions: // - nonce is 0 // - balance amount for evm denom is 0 // - account code hash is empty // // Non-ethereum accounts are considered not empty func (k *Keeper) Empty(addr common.Address) bool { nonce := uint64(0) codeHash := types.EmptyCodeHash cosmosAddr := sdk.AccAddress(addr.Bytes()) account := k.accountKeeper.GetAccount(k.ctx, cosmosAddr) if account != nil { nonce = account.GetSequence() ethAccount, isEthAccount := account.(*ethermint.EthAccount) if !isEthAccount { return false } codeHash = common.HexToHash(ethAccount.CodeHash).Bytes() } balance := k.GetBalance(addr) hasZeroBalance := balance.Sign() == 0 hasEmptyCodeHash := bytes.Equal(codeHash, types.EmptyCodeHash) return hasZeroBalance && nonce == 0 && hasEmptyCodeHash } // ---------------------------------------------------------------------------- // Access List // ---------------------------------------------------------------------------- // PrepareAccessList handles the preparatory steps for executing a state transition with // regards to both EIP-2929 and EIP-2930: // // - Add sender to access list (2929) // - Add destination to access list (2929) // - Add precompiles to access list (2929) // - Add the contents of the optional tx access list (2930) // // This method should only be called if Yolov3/Berlin/2929+2930 is applicable at the current number. func (k *Keeper) PrepareAccessList(sender common.Address, dest *common.Address, precompiles []common.Address, txAccesses ethtypes.AccessList) { k.AddAddressToAccessList(sender) if dest != nil { k.AddAddressToAccessList(*dest) // If it's a create-tx, the destination will be added inside evm.create } for _, addr := range precompiles { k.AddAddressToAccessList(addr) } for _, tuple := range txAccesses { k.AddAddressToAccessList(tuple.Address) for _, key := range tuple.StorageKeys { k.AddSlotToAccessList(tuple.Address, key) } } } // AddressInAccessList returns true if the address is registered on the transient store. func (k *Keeper) AddressInAccessList(addr common.Address) bool { ts := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientAccessListAddress) return ts.Has(addr.Bytes()) } // SlotInAccessList checks if the address and the slots are registered in the transient store func (k *Keeper) SlotInAccessList(addr common.Address, slot common.Hash) (addressOk bool, slotOk bool) { addressOk = k.AddressInAccessList(addr) slotOk = k.addressSlotInAccessList(addr, slot) return addressOk, slotOk } // addressSlotInAccessList returns true if the address's slot is registered on the transient store. func (k *Keeper) addressSlotInAccessList(addr common.Address, slot common.Hash) bool { ts := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientAccessListSlot) key := append(addr.Bytes(), slot.Bytes()...) return ts.Has(key) } // AddAddressToAccessList adds the given address to the access list. If the address is already // in the access list, this function performs a no-op. func (k *Keeper) AddAddressToAccessList(addr common.Address) { if k.AddressInAccessList(addr) { return } ts := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientAccessListAddress) ts.Set(addr.Bytes(), []byte{0x1}) } // AddSlotToAccessList adds the given (address, slot) to the access list. If the address and slot are // already in the access list, this function performs a no-op. func (k *Keeper) AddSlotToAccessList(addr common.Address, slot common.Hash) { k.AddAddressToAccessList(addr) if k.addressSlotInAccessList(addr, slot) { return } ts := prefix.NewStore(k.ctx.TransientStore(k.transientKey), types.KeyPrefixTransientAccessListSlot) key := append(addr.Bytes(), slot.Bytes()...) ts.Set(key, []byte{0x1}) } // ---------------------------------------------------------------------------- // Snapshotting // ---------------------------------------------------------------------------- // Snapshot return zero as the state changes won't be committed if the state transition fails. So there // is no need to snapshot before the VM execution. // See Cosmos SDK docs for more info: https://docs.cosmos.network/master/core/baseapp.html#delivertx-state-updates func (k *Keeper) Snapshot() int { return 0 } // RevertToSnapshot performs a no-op because when a transaction execution fails on the EVM, the state // won't be persisted during ABCI DeliverTx. func (k *Keeper) RevertToSnapshot(_ int) {} // ---------------------------------------------------------------------------- // Log // ---------------------------------------------------------------------------- // AddLog appends the given ethereum Log to the list of Logs associated with the transaction hash kept in the current // context. This function also fills in the tx hash, block hash, tx index and log index fields before setting the log // to store. func (k *Keeper) AddLog(log *ethtypes.Log) { log.BlockHash = common.BytesToHash(k.ctx.HeaderHash()) log.TxIndex = uint(k.GetTxIndexTransient()) log.TxHash = k.GetTxHashTransient() log.Index = uint(k.GetLogSizeTransient()) k.IncreaseLogSizeTransient() logs := k.GetTxLogs(log.TxHash) logs = append(logs, log) k.SetLogs(log.TxHash, logs) k.Logger(k.ctx).Debug( "log added", "tx-hash-ethereum", log.TxHash.Hex(), "log-index", int(log.Index), ) } // ---------------------------------------------------------------------------- // Trie // ---------------------------------------------------------------------------- // AddPreimage performs a no-op since the EnablePreimageRecording flag is disabled // on the vm.Config during state transitions. No store trie preimages are written // to the database. func (k *Keeper) AddPreimage(_ common.Hash, _ []byte) {} // ---------------------------------------------------------------------------- // Iterator // ---------------------------------------------------------------------------- // ForEachStorage calls CommitStateDB.ForEachStorage using passed in context func (k *Keeper) ForEachStorage(addr common.Address, cb func(key, value common.Hash) bool) error { store := k.ctx.KVStore(k.storeKey) prefix := types.AddressStoragePrefix(addr) iterator := sdk.KVStorePrefixIterator(store, prefix) defer iterator.Close() for ; iterator.Valid(); iterator.Next() { // TODO: check if the key prefix needs to be trimmed key := common.BytesToHash(iterator.Key()) value := common.BytesToHash(iterator.Value()) // check if iteration stops if cb(key, value) { return nil } } return nil }