// Copyright 2016 The go-ethereum Authors // This file is part of the go-ethereum library. // // The go-ethereum library is free software: you can redistribute it and/or modify // it under the terms of the GNU Lesser General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // The go-ethereum library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public License // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. package misc import ( "bytes" "errors" "math/big" "github.com/ava-labs/coreth/core/state" "github.com/ava-labs/coreth/core/types" "github.com/ava-labs/coreth/params" ) var ( // ErrBadProDAOExtra is returned if a header doesn't support the DAO fork on a // pro-fork client. ErrBadProDAOExtra = errors.New("bad DAO pro-fork extra-data") // ErrBadNoDAOExtra is returned if a header does support the DAO fork on a no- // fork client. ErrBadNoDAOExtra = errors.New("bad DAO no-fork extra-data") ) // VerifyDAOHeaderExtraData validates the extra-data field of a block header to // ensure it conforms to DAO hard-fork rules. // // DAO hard-fork extension to the header validity: // a) if the node is no-fork, do not accept blocks in the [fork, fork+10) range // with the fork specific extra-data set // b) if the node is pro-fork, require blocks in the specific range to have the // unique extra-data set. func VerifyDAOHeaderExtraData(config *params.ChainConfig, header *types.Header) error { // Short circuit validation if the node doesn't care about the DAO fork if config.DAOForkBlock == nil { return nil } // Make sure the block is within the fork's modified extra-data range limit := new(big.Int).Add(config.DAOForkBlock, params.DAOForkExtraRange) if header.Number.Cmp(config.DAOForkBlock) < 0 || header.Number.Cmp(limit) >= 0 { return nil } // Depending on whether we support or oppose the fork, validate the extra-data contents if config.DAOForkSupport { if !bytes.Equal(header.Extra, params.DAOForkBlockExtra) { return ErrBadProDAOExtra } } else { if bytes.Equal(header.Extra, params.DAOForkBlockExtra) { return ErrBadNoDAOExtra } } // All ok, header has the same extra-data we expect return nil } // ApplyDAOHardFork modifies the state database according to the DAO hard-fork // rules, transferring all balances of a set of DAO accounts to a single refund // contract. func ApplyDAOHardFork(statedb *state.StateDB) { // Retrieve the contract to refund balances into if !statedb.Exist(params.DAORefundContract) { statedb.CreateAccount(params.DAORefundContract) } // Move every DAO account and extra-balance account funds into the refund contract for _, addr := range params.DAODrainList() { statedb.AddBalance(params.DAORefundContract, statedb.GetBalance(addr)) statedb.SetBalance(addr, new(big.Int)) } }