// ChainConfig is the core config which determines the blockchain settings.
//
// ChainConfig is stored in the database on a per block basis. This means
// that any network, identified by its genesis block, can have its own
// set of configuration options.
type ChainConfig struct {
	ChainID *big.Int `json:"chainId"` // chainId identifies the current chain and is used for replay protection
	HomesteadBlock *big.Int `json:"homesteadBlock,omitempty"` // Homestead switch block (nil = no fork, 0 = already homestead)

	// EIP150 implements the Gas price changes (https://github.com/ethereum/EIPs/issues/150)
	EIP150Block *big.Int    `json:"eip150Block,omitempty"` // EIP150 HF block (nil = no fork)
	EIP150Hash  common.Hash `json:"eip150Hash,omitempty"`  // EIP150 HF hash (needed for header only clients as only gas pricing changed)

	EIP155Block *big.Int `json:"eip155Block,omitempty"` // EIP155 HF block
	EIP158Block *big.Int `json:"eip158Block,omitempty"` // EIP158 HF block
}
 

今天看程式碼注意到了這個配置，就查了一下。

EIP155Block　Simple replay attack protection就是防止測試網中的代幣傳送到主網中去

在區塊高度2,675,000產生硬分叉，發生時間2016,11,22．測試網在 1,885,000.硬分叉。

	// MainnetChainConfig is the chain parameters to run a node on the main network.
	MainnetChainConfig = &ChainConfig{
		ChainID:             big.NewInt(1),
		HomesteadBlock:      big.NewInt(1150000),
		EIP150Hash:          common.HexToHash("0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0"),
		EIP155Block:         big.NewInt(2675000),
		EIP158Block:         big.NewInt(2675000),
	}
 

升級在於以前計算hash使用nonce, gasprice, startgas, to, value, data六種資料，現在使用９種，前６中加上簽名資料Ｒ，Ｓ。加上CHAIN_ID做ｈａｓｈ。

func (s EIP155Signer) Hash(tx *Transaction) common.Hash {
	return rlpHash([]interface{}{
		tx.data.AccountNonce,
		tx.data.Price,
		tx.data.GasLimit,
		tx.data.Recipient,
		tx.data.Amount,
		tx.data.Payload,
		s.chainId, uint(0), uint(0),
	})
}
 

// WithSignature returns a new transaction with the given signature. This signature
// needs to be in the [R || S || V] format where V is 0 or 1.
func (s EIP155Signer) SignatureValues(tx *Transaction, sig []byte) (R, S, V *big.Int, err error) {
	R, S, V, err = HomesteadSigner{}.SignatureValues(tx, sig)
	if err != nil {
		return nil, nil, nil, err
	}
	if s.chainId.Sign() != 0 {
		V = big.NewInt(int64(sig[64] + 35))
		V.Add(V, s.chainIdMul)
	}
	return R, S, V, nil
}

https://blog.ethereum.org/2016/11/18/hard-fork-no-4-spurious-dragon/

eip155以太坊155的提高協議。偽龍

https://github.com/ethereum/EIPs/blob/master/EIPS/eip-155.md

networkID的簡單介紹

https://ethereum.stackexchange.com/questions/17051/how-to-select-a-network-id-or-is-there-a-list-of-network-ids

拜占庭硬分叉區塊檢視

https://fork.codetract.io/