86 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
		
		
			
		
	
	
			86 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
|   | // 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/ethereum/go-ethereum/core/state" | ||
|  | 	"github.com/ethereum/go-ethereum/core/types" | ||
|  | 	"github.com/ethereum/go-ethereum/params" | ||
|  | ) | ||
|  | 
 | ||
|  | var ( | ||
|  | 	// ErrBadProDAOExtra is returned if a header doens'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 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)) | ||
|  | 	} | ||
|  | } |