package keeper import ( "bytes" "fmt" "math/big" "github.com/cosmos/cosmos-sdk/store/prefix" sdk "github.com/cosmos/cosmos-sdk/types" sdkerrors "github.com/cosmos/cosmos-sdk/types/errors" "github.com/ethereum/go-ethereum/common" ethermint "github.com/tharsis/ethermint/types" "github.com/tharsis/ethermint/x/evm/statedb" "github.com/tharsis/ethermint/x/evm/types" ) var _ statedb.Keeper = &Keeper{} // ---------------------------------------------------------------------------- // statedb.Keeper implementation // ---------------------------------------------------------------------------- // GetAccount returns nil if account is not exist, returns error if it's not `EthAccount` func (k *Keeper) GetAccount(ctx sdk.Context, addr common.Address) (*statedb.Account, error) { acct, err := k.GetAccountWithoutBalance(ctx, addr) if acct == nil || err != nil { return acct, err } acct.Balance = k.GetBalance(ctx, addr) return acct, nil } // GetState loads contract state from database, implements `statedb.Keeper` interface. func (k *Keeper) GetState(ctx sdk.Context, addr common.Address, key common.Hash) common.Hash { store := prefix.NewStore(ctx.KVStore(k.storeKey), types.AddressStoragePrefix(addr)) value := store.Get(key.Bytes()) if len(value) == 0 { return common.Hash{} } return common.BytesToHash(value) } // GetCode loads contract code from database, implements `statedb.Keeper` interface. func (k *Keeper) GetCode(ctx sdk.Context, codeHash common.Hash) []byte { store := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefixCode) return store.Get(codeHash.Bytes()) } // ForEachStorage iterate contract storage, callback return false to break early func (k *Keeper) ForEachStorage(ctx sdk.Context, addr common.Address, cb func(key, value common.Hash) bool) { store := ctx.KVStore(k.storeKey) prefix := types.AddressStoragePrefix(addr) iterator := sdk.KVStorePrefixIterator(store, prefix) defer iterator.Close() for ; iterator.Valid(); iterator.Next() { key := common.BytesToHash(iterator.Key()) value := common.BytesToHash(iterator.Value()) // check if iteration stops if !cb(key, value) { return } } } // SetBalance update account's balance, compare with current balance first, then decide to mint or burn. func (k *Keeper) SetBalance(ctx sdk.Context, addr common.Address, amount *big.Int) error { cosmosAddr := sdk.AccAddress(addr.Bytes()) params := k.GetParams(ctx) coin := k.bankKeeper.GetBalance(ctx, cosmosAddr, params.EvmDenom) balance := coin.Amount.BigInt() delta := new(big.Int).Sub(amount, balance) switch delta.Sign() { case 1: // mint coins := sdk.NewCoins(sdk.NewCoin(params.EvmDenom, sdk.NewIntFromBigInt(delta))) if err := k.bankKeeper.MintCoins(ctx, types.ModuleName, coins); err != nil { return err } if err := k.bankKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, cosmosAddr, coins); err != nil { return err } case -1: // burn coins := sdk.NewCoins(sdk.NewCoin(params.EvmDenom, sdk.NewIntFromBigInt(new(big.Int).Neg(delta)))) if err := k.bankKeeper.SendCoinsFromAccountToModule(ctx, cosmosAddr, types.ModuleName, coins); err != nil { return err } if err := k.bankKeeper.BurnCoins(ctx, types.ModuleName, coins); err != nil { return err } default: // not changed } return nil } // SetAccount updates nonce/balance/codeHash together. func (k *Keeper) SetAccount(ctx sdk.Context, addr common.Address, account statedb.Account) error { // update account cosmosAddr := sdk.AccAddress(addr.Bytes()) acct := k.accountKeeper.GetAccount(ctx, cosmosAddr) if acct == nil { acct = k.accountKeeper.NewAccountWithAddress(ctx, cosmosAddr) } ethAcct, ok := acct.(*ethermint.EthAccount) if !ok { return sdkerrors.Wrapf(types.ErrInvalidAccount, "type %T, address %s", acct, addr) } if err := ethAcct.SetSequence(account.Nonce); err != nil { return err } ethAcct.CodeHash = common.BytesToHash(account.CodeHash).Hex() k.accountKeeper.SetAccount(ctx, ethAcct) err := k.SetBalance(ctx, addr, account.Balance) k.Logger(ctx).Debug( "account updated", "ethereum-address", addr.Hex(), "nonce", account.Nonce, "codeHash", common.BytesToHash(account.CodeHash).Hex(), "balance", account.Balance, ) return err } // SetState update contract storage, delete if value is empty. func (k *Keeper) SetState(ctx sdk.Context, addr common.Address, key common.Hash, value []byte) { store := prefix.NewStore(ctx.KVStore(k.storeKey), types.AddressStoragePrefix(addr)) action := "updated" if len(value) == 0 { store.Delete(key.Bytes()) action = "deleted" } else { store.Set(key.Bytes(), value) } k.Logger(ctx).Debug( fmt.Sprintf("state %s", action), "ethereum-address", addr.Hex(), "key", key.Hex(), ) } // SetCode set contract code, delete if code is empty. func (k *Keeper) SetCode(ctx sdk.Context, codeHash, code []byte) { store := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefixCode) // store or delete code action := "updated" if len(code) == 0 { store.Delete(codeHash) action = "deleted" } else { store.Set(codeHash, code) } k.Logger(ctx).Debug( fmt.Sprintf("code %s", action), "code-hash", common.BytesToHash(codeHash).Hex(), ) } // DeleteAccount handles contract's suicide call: // - clear balance // - remove code // - remove states // - remove auth account func (k *Keeper) DeleteAccount(ctx sdk.Context, addr common.Address) error { cosmosAddr := sdk.AccAddress(addr.Bytes()) acct := k.accountKeeper.GetAccount(ctx, cosmosAddr) if acct == nil { return nil } ethAcct, ok := acct.(*ethermint.EthAccount) if !ok { return sdkerrors.Wrapf(types.ErrInvalidAccount, "type %T, address %s", acct, addr) } // clear balance if err := k.SetBalance(ctx, addr, new(big.Int)); err != nil { return err } // remove code codeHash := common.HexToHash(ethAcct.CodeHash).Bytes() if !bytes.Equal(codeHash, types.EmptyCodeHash) { k.SetCode(ctx, codeHash, nil) } // clear storage k.ForEachStorage(ctx, addr, func(key, _ common.Hash) bool { k.SetState(ctx, addr, key, nil) return true }) // remove auth account k.accountKeeper.RemoveAccount(ctx, acct) k.Logger(ctx).Debug( "account suicided", "ethereum-address", addr.Hex(), "cosmos-address", cosmosAddr.String(), ) return nil }