Merge branch 'multi-coin'

1 files changed, 541 insertions, 0 deletions

diff --git a/params/config.go b/params/config.go
new file mode 100644
index 0000000..23286cc
--- /dev/null
+++ b/params/config.go
@@ -0,0 +1,541 @@
+// 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 params
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math/big"
+
+	"github.com/ava-labs/go-ethereum/common"
+	"github.com/ava-labs/go-ethereum/crypto"
+)
+
+// Genesis hashes to enforce below configs on.
+var (
+	MainnetGenesisHash = common.HexToHash("0xd4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3")
+	TestnetGenesisHash = common.HexToHash("0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d")
+	RinkebyGenesisHash = common.HexToHash("0x6341fd3daf94b748c72ced5a5b26028f2474f5f00d824504e4fa37a75767e177")
+	GoerliGenesisHash  = common.HexToHash("0xbf7e331f7f7c1dd2e05159666b3bf8bc7a8a3a9eb1d518969eab529dd9b88c1a")
+)
+
+// TrustedCheckpoints associates each known checkpoint with the genesis hash of
+// the chain it belongs to.
+var TrustedCheckpoints = map[common.Hash]*TrustedCheckpoint{
+	MainnetGenesisHash: MainnetTrustedCheckpoint,
+	TestnetGenesisHash: TestnetTrustedCheckpoint,
+	RinkebyGenesisHash: RinkebyTrustedCheckpoint,
+	GoerliGenesisHash:  GoerliTrustedCheckpoint,
+}
+
+// CheckpointOracles associates each known checkpoint oracles with the genesis hash of
+// the chain it belongs to.
+var CheckpointOracles = map[common.Hash]*CheckpointOracleConfig{
+	MainnetGenesisHash: MainnetCheckpointOracle,
+	TestnetGenesisHash: TestnetCheckpointOracle,
+	RinkebyGenesisHash: RinkebyCheckpointOracle,
+	GoerliGenesisHash:  GoerliCheckpointOracle,
+}
+
+var (
+	// MainnetChainConfig is the chain parameters to run a node on the main network.
+	MainnetChainConfig = &ChainConfig{
+		ChainID:             big.NewInt(1),
+		HomesteadBlock:      big.NewInt(1150000),
+		DAOForkBlock:        big.NewInt(1920000),
+		DAOForkSupport:      true,
+		EIP150Block:         big.NewInt(2463000),
+		EIP150Hash:          common.HexToHash("0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0"),
+		EIP155Block:         big.NewInt(2675000),
+		EIP158Block:         big.NewInt(2675000),
+		ByzantiumBlock:      big.NewInt(4370000),
+		ConstantinopleBlock: big.NewInt(7280000),
+		PetersburgBlock:     big.NewInt(7280000),
+		IstanbulBlock:       nil,
+		Ethash:              new(EthashConfig),
+	}
+
+	// MainnetTrustedCheckpoint contains the light client trusted checkpoint for the main network.
+	MainnetTrustedCheckpoint = &TrustedCheckpoint{
+		SectionIndex: 253,
+		SectionHead:  common.HexToHash("0xf35fabd036e2030196183bb70ae194f6ce1ea7b58559e3825c168f1df9c0a258"),
+		CHTRoot:      common.HexToHash("0x8992849e2be3390696eaf66312626e484045501cd3ec207922c27a6a80a7bb07"),
+		BloomRoot:    common.HexToHash("0xcc510b51ca4d73fb3fdf43208d73286f8f23817cdc31b8ea9f4de8d645f07df4"),
+	}
+
+	// MainnetCheckpointOracle contains a set of configs for the main network oracle.
+	MainnetCheckpointOracle = &CheckpointOracleConfig{
+		Address: common.HexToAddress("0x9a9070028361F7AAbeB3f2F2Dc07F82C4a98A02a"),
+		Signers: []common.Address{
+			common.HexToAddress("0x1b2C260efc720BE89101890E4Db589b44E950527"), // Peter
+			common.HexToAddress("0x78d1aD571A1A09D60D9BBf25894b44e4C8859595"), // Martin
+			common.HexToAddress("0x286834935f4A8Cfb4FF4C77D5770C2775aE2b0E7"), // Zsolt
+			common.HexToAddress("0xb86e2B0Ab5A4B1373e40c51A7C712c70Ba2f9f8E"), // Gary
+			common.HexToAddress("0x0DF8fa387C602AE62559cC4aFa4972A7045d6707"), // Guillaume
+		},
+		Threshold: 2,
+	}
+
+	// TestnetChainConfig contains the chain parameters to run a node on the Ropsten test network.
+	TestnetChainConfig = &ChainConfig{
+		ChainID:             big.NewInt(3),
+		HomesteadBlock:      big.NewInt(0),
+		DAOForkBlock:        nil,
+		DAOForkSupport:      true,
+		EIP150Block:         big.NewInt(0),
+		EIP150Hash:          common.HexToHash("0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d"),
+		EIP155Block:         big.NewInt(10),
+		EIP158Block:         big.NewInt(10),
+		ByzantiumBlock:      big.NewInt(1700000),
+		ConstantinopleBlock: big.NewInt(4230000),
+		PetersburgBlock:     big.NewInt(4939394),
+		IstanbulBlock:       nil,
+		Ethash:              new(EthashConfig),
+	}
+
+	// TestnetTrustedCheckpoint contains the light client trusted checkpoint for the Ropsten test network.
+	TestnetTrustedCheckpoint = &TrustedCheckpoint{
+		SectionIndex: 187,
+		SectionHead:  common.HexToHash("0x7d6db64d8ec43303e4392fb726d2346f7231b246decca3d8140dd7e2c0d0b07d"),
+		CHTRoot:      common.HexToHash("0xa5095e1a004a8642fb93ca682eb91e8f20ef5bce151e47404fbb68772d17705b"),
+		BloomRoot:    common.HexToHash("0x90b28050f948ec6fb35b23a91d9aed38ce0c92d3cdd6e1d383c1bddf8b4071cf"),
+	}
+
+	// TestnetCheckpointOracle contains a set of configs for the Ropsten test network oracle.
+	TestnetCheckpointOracle = &CheckpointOracleConfig{
+		Address: common.HexToAddress("0xEF79475013f154E6A65b54cB2742867791bf0B84"),
+		Signers: []common.Address{
+			common.HexToAddress("0x32162F3581E88a5f62e8A61892B42C46E2c18f7b"), // Peter
+			common.HexToAddress("0x78d1aD571A1A09D60D9BBf25894b44e4C8859595"), // Martin
+			common.HexToAddress("0x286834935f4A8Cfb4FF4C77D5770C2775aE2b0E7"), // Zsolt
+			common.HexToAddress("0xb86e2B0Ab5A4B1373e40c51A7C712c70Ba2f9f8E"), // Gary
+			common.HexToAddress("0x0DF8fa387C602AE62559cC4aFa4972A7045d6707"), // Guillaume
+		},
+		Threshold: 2,
+	}
+
+	// RinkebyChainConfig contains the chain parameters to run a node on the Rinkeby test network.
+	RinkebyChainConfig = &ChainConfig{
+		ChainID:             big.NewInt(4),
+		HomesteadBlock:      big.NewInt(1),
+		DAOForkBlock:        nil,
+		DAOForkSupport:      true,
+		EIP150Block:         big.NewInt(2),
+		EIP150Hash:          common.HexToHash("0x9b095b36c15eaf13044373aef8ee0bd3a382a5abb92e402afa44b8249c3a90e9"),
+		EIP155Block:         big.NewInt(3),
+		EIP158Block:         big.NewInt(3),
+		ByzantiumBlock:      big.NewInt(1035301),
+		ConstantinopleBlock: big.NewInt(3660663),
+		PetersburgBlock:     big.NewInt(4321234),
+		IstanbulBlock:       nil,
+		Clique: &CliqueConfig{
+			Period: 15,
+			Epoch:  30000,
+		},
+	}
+
+	// RinkebyTrustedCheckpoint contains the light client trusted checkpoint for the Rinkeby test network.
+	RinkebyTrustedCheckpoint = &TrustedCheckpoint{
+		SectionIndex: 148,
+		SectionHead:  common.HexToHash("0x45918f4686732c2a3e80827e1bc39cdb6a27fa362ddfe1fdfb61c69a7f1df1a9"),
+		CHTRoot:      common.HexToHash("0x8ac7046391fec14834a2a0183513937c0b5f696666545991477d24b067008961"),
+		BloomRoot:    common.HexToHash("0xfe4b852517612d7da54bf7e9fc18861a83171a93c72583bb6a61893b74422168"),
+	}
+
+	// RinkebyCheckpointOracle contains a set of configs for the Rinkeby test network oracle.
+	RinkebyCheckpointOracle = &CheckpointOracleConfig{
+		Address: common.HexToAddress("0xebe8eFA441B9302A0d7eaECc277c09d20D684540"),
+		Signers: []common.Address{
+			common.HexToAddress("0xd9c9cd5f6779558b6e0ed4e6acf6b1947e7fa1f3"), // Peter
+			common.HexToAddress("0x78d1aD571A1A09D60D9BBf25894b44e4C8859595"), // Martin
+			common.HexToAddress("0x286834935f4A8Cfb4FF4C77D5770C2775aE2b0E7"), // Zsolt
+			common.HexToAddress("0xb86e2B0Ab5A4B1373e40c51A7C712c70Ba2f9f8E"), // Gary
+		},
+		Threshold: 2,
+	}
+
+	// GoerliChainConfig contains the chain parameters to run a node on the Görli test network.
+	GoerliChainConfig = &ChainConfig{
+		ChainID:             big.NewInt(5),
+		HomesteadBlock:      big.NewInt(0),
+		DAOForkBlock:        nil,
+		DAOForkSupport:      true,
+		EIP150Block:         big.NewInt(0),
+		EIP155Block:         big.NewInt(0),
+		EIP158Block:         big.NewInt(0),
+		ByzantiumBlock:      big.NewInt(0),
+		ConstantinopleBlock: big.NewInt(0),
+		PetersburgBlock:     big.NewInt(0),
+		IstanbulBlock:       nil,
+		Clique: &CliqueConfig{
+			Period: 15,
+			Epoch:  30000,
+		},
+	}
+
+	// GoerliTrustedCheckpoint contains the light client trusted checkpoint for the Görli test network.
+	GoerliTrustedCheckpoint = &TrustedCheckpoint{
+		SectionIndex: 32,
+		SectionHead:  common.HexToHash("0x50eaedd8361fa9edd0ac2dec410310b9bdf67b963b60f3b1dce47f84b30670f9"),
+		CHTRoot:      common.HexToHash("0x6504db73139f75ffa9102ae980e41b361cf3d5b66cea06c79cde9f457368820c"),
+		BloomRoot:    common.HexToHash("0x7551ae027bb776252a20ded51ee2ff0cbfbd1d8d57261b9161cc1f2f80237001"),
+	}
+
+	// GoerliCheckpointOracle contains a set of configs for the Goerli test network oracle.
+	GoerliCheckpointOracle = &CheckpointOracleConfig{
+		Address: common.HexToAddress("0x18CA0E045F0D772a851BC7e48357Bcaab0a0795D"),
+		Signers: []common.Address{
+			common.HexToAddress("0x4769bcaD07e3b938B7f43EB7D278Bc7Cb9efFb38"), // Peter
+			common.HexToAddress("0x78d1aD571A1A09D60D9BBf25894b44e4C8859595"), // Martin
+			common.HexToAddress("0x286834935f4A8Cfb4FF4C77D5770C2775aE2b0E7"), // Zsolt
+			common.HexToAddress("0xb86e2B0Ab5A4B1373e40c51A7C712c70Ba2f9f8E"), // Gary
+			common.HexToAddress("0x0DF8fa387C602AE62559cC4aFa4972A7045d6707"), // Guillaume
+		},
+		Threshold: 2,
+	}
+
+	// AllEthashProtocolChanges contains every protocol change (EIPs) introduced
+	// and accepted by the Ethereum core developers into the Ethash consensus.
+	//
+	// This configuration is intentionally not using keyed fields to force anyone
+	// adding flags to the config to also have to set these fields.
+	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+
+	// AllCliqueProtocolChanges contains every protocol change (EIPs) introduced
+	// and accepted by the Ethereum core developers into the Clique consensus.
+	//
+	// This configuration is intentionally not using keyed fields to force anyone
+	// adding flags to the config to also have to set these fields.
+	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
+
+	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, new(EthashConfig), nil}
+	TestRules       = TestChainConfig.Rules(new(big.Int))
+)
+
+// TrustedCheckpoint represents a set of post-processed trie roots (CHT and
+// BloomTrie) associated with the appropriate section index and head hash. It is
+// used to start light syncing from this checkpoint and avoid downloading the
+// entire header chain while still being able to securely access old headers/logs.
+type TrustedCheckpoint struct {
+	SectionIndex uint64      `json:"sectionIndex"`
+	SectionHead  common.Hash `json:"sectionHead"`
+	CHTRoot      common.Hash `json:"chtRoot"`
+	BloomRoot    common.Hash `json:"bloomRoot"`
+}
+
+// HashEqual returns an indicator comparing the itself hash with given one.
+func (c *TrustedCheckpoint) HashEqual(hash common.Hash) bool {
+	if c.Empty() {
+		return hash == common.Hash{}
+	}
+	return c.Hash() == hash
+}
+
+// Hash returns the hash of checkpoint's four key fields(index, sectionHead, chtRoot and bloomTrieRoot).
+func (c *TrustedCheckpoint) Hash() common.Hash {
+	buf := make([]byte, 8+3*common.HashLength)
+	binary.BigEndian.PutUint64(buf, c.SectionIndex)
+	copy(buf[8:], c.SectionHead.Bytes())
+	copy(buf[8+common.HashLength:], c.CHTRoot.Bytes())
+	copy(buf[8+2*common.HashLength:], c.BloomRoot.Bytes())
+	return crypto.Keccak256Hash(buf)
+}
+
+// Empty returns an indicator whether the checkpoint is regarded as empty.
+func (c *TrustedCheckpoint) Empty() bool {
+	return c.SectionHead == (common.Hash{}) || c.CHTRoot == (common.Hash{}) || c.BloomRoot == (common.Hash{})
+}
+
+// CheckpointOracleConfig represents a set of checkpoint contract(which acts as an oracle)
+// config which used for light client checkpoint syncing.
+type CheckpointOracleConfig struct {
+	Address   common.Address   `json:"address"`
+	Signers   []common.Address `json:"signers"`
+	Threshold uint64           `json:"threshold"`
+}
+
+// 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)
+
+	DAOForkBlock   *big.Int `json:"daoForkBlock,omitempty"`   // TheDAO hard-fork switch block (nil = no fork)
+	DAOForkSupport bool     `json:"daoForkSupport,omitempty"` // Whether the nodes supports or opposes the DAO hard-fork
+
+	// 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
+
+	ByzantiumBlock      *big.Int `json:"byzantiumBlock,omitempty"`      // Byzantium switch block (nil = no fork, 0 = already on byzantium)
+	ConstantinopleBlock *big.Int `json:"constantinopleBlock,omitempty"` // Constantinople switch block (nil = no fork, 0 = already activated)
+	PetersburgBlock     *big.Int `json:"petersburgBlock,omitempty"`     // Petersburg switch block (nil = same as Constantinople)
+	IstanbulBlock       *big.Int `json:"istanbulBlock,omitempty"`       // Istanbul switch block (nil = no fork, 0 = already on istanbul)
+	EWASMBlock          *big.Int `json:"ewasmBlock,omitempty"`          // EWASM switch block (nil = no fork, 0 = already activated)
+
+	// Various consensus engines
+	Ethash *EthashConfig `json:"ethash,omitempty"`
+	Clique *CliqueConfig `json:"clique,omitempty"`
+}
+
+// EthashConfig is the consensus engine configs for proof-of-work based sealing.
+type EthashConfig struct{}
+
+// String implements the stringer interface, returning the consensus engine details.
+func (c *EthashConfig) String() string {
+	return "ethash"
+}
+
+// CliqueConfig is the consensus engine configs for proof-of-authority based sealing.
+type CliqueConfig struct {
+	Period uint64 `json:"period"` // Number of seconds between blocks to enforce
+	Epoch  uint64 `json:"epoch"`  // Epoch length to reset votes and checkpoint
+}
+
+// String implements the stringer interface, returning the consensus engine details.
+func (c *CliqueConfig) String() string {
+	return "clique"
+}
+
+// String implements the fmt.Stringer interface.
+func (c *ChainConfig) String() string {
+	var engine interface{}
+	switch {
+	case c.Ethash != nil:
+		engine = c.Ethash
+	case c.Clique != nil:
+		engine = c.Clique
+	default:
+		engine = "unknown"
+	}
+	return fmt.Sprintf("{ChainID: %v Homestead: %v DAO: %v DAOSupport: %v EIP150: %v EIP155: %v EIP158: %v Byzantium: %v Constantinople: %v Petersburg: %v Istanbul: %v Engine: %v}",
+		c.ChainID,
+		c.HomesteadBlock,
+		c.DAOForkBlock,
+		c.DAOForkSupport,
+		c.EIP150Block,
+		c.EIP155Block,
+		c.EIP158Block,
+		c.ByzantiumBlock,
+		c.ConstantinopleBlock,
+		c.PetersburgBlock,
+		c.IstanbulBlock,
+		engine,
+	)
+}
+
+// IsHomestead returns whether num is either equal to the homestead block or greater.
+func (c *ChainConfig) IsHomestead(num *big.Int) bool {
+	return isForked(c.HomesteadBlock, num)
+}
+
+// IsDAOFork returns whether num is either equal to the DAO fork block or greater.
+func (c *ChainConfig) IsDAOFork(num *big.Int) bool {
+	return isForked(c.DAOForkBlock, num)
+}
+
+// IsEIP150 returns whether num is either equal to the EIP150 fork block or greater.
+func (c *ChainConfig) IsEIP150(num *big.Int) bool {
+	return isForked(c.EIP150Block, num)
+}
+
+// IsEIP155 returns whether num is either equal to the EIP155 fork block or greater.
+func (c *ChainConfig) IsEIP155(num *big.Int) bool {
+	return isForked(c.EIP155Block, num)
+}
+
+// IsEIP158 returns whether num is either equal to the EIP158 fork block or greater.
+func (c *ChainConfig) IsEIP158(num *big.Int) bool {
+	return isForked(c.EIP158Block, num)
+}
+
+// IsByzantium returns whether num is either equal to the Byzantium fork block or greater.
+func (c *ChainConfig) IsByzantium(num *big.Int) bool {
+	return isForked(c.ByzantiumBlock, num)
+}
+
+// IsConstantinople returns whether num is either equal to the Constantinople fork block or greater.
+func (c *ChainConfig) IsConstantinople(num *big.Int) bool {
+	return isForked(c.ConstantinopleBlock, num)
+}
+
+// IsPetersburg returns whether num is either
+// - equal to or greater than the PetersburgBlock fork block,
+// - OR is nil, and Constantinople is active
+func (c *ChainConfig) IsPetersburg(num *big.Int) bool {
+	return isForked(c.PetersburgBlock, num) || c.PetersburgBlock == nil && isForked(c.ConstantinopleBlock, num)
+}
+
+// IsIstanbul returns whether num is either equal to the Istanbul fork block or greater.
+func (c *ChainConfig) IsIstanbul(num *big.Int) bool {
+	return isForked(c.IstanbulBlock, num)
+}
+
+// IsEWASM returns whether num represents a block number after the EWASM fork
+func (c *ChainConfig) IsEWASM(num *big.Int) bool {
+	return isForked(c.EWASMBlock, num)
+}
+
+// CheckCompatible checks whether scheduled fork transitions have been imported
+// with a mismatching chain configuration.
+func (c *ChainConfig) CheckCompatible(newcfg *ChainConfig, height uint64) *ConfigCompatError {
+	bhead := new(big.Int).SetUint64(height)
+
+	// Iterate checkCompatible to find the lowest conflict.
+	var lasterr *ConfigCompatError
+	for {
+		err := c.checkCompatible(newcfg, bhead)
+		if err == nil || (lasterr != nil && err.RewindTo == lasterr.RewindTo) {
+			break
+		}
+		lasterr = err
+		bhead.SetUint64(err.RewindTo)
+	}
+	return lasterr
+}
+
+func (c *ChainConfig) checkCompatible(newcfg *ChainConfig, head *big.Int) *ConfigCompatError {
+	if isForkIncompatible(c.HomesteadBlock, newcfg.HomesteadBlock, head) {
+		return newCompatError("Homestead fork block", c.HomesteadBlock, newcfg.HomesteadBlock)
+	}
+	if isForkIncompatible(c.DAOForkBlock, newcfg.DAOForkBlock, head) {
+		return newCompatError("DAO fork block", c.DAOForkBlock, newcfg.DAOForkBlock)
+	}
+	if c.IsDAOFork(head) && c.DAOForkSupport != newcfg.DAOForkSupport {
+		return newCompatError("DAO fork support flag", c.DAOForkBlock, newcfg.DAOForkBlock)
+	}
+	if isForkIncompatible(c.EIP150Block, newcfg.EIP150Block, head) {
+		return newCompatError("EIP150 fork block", c.EIP150Block, newcfg.EIP150Block)
+	}
+	if isForkIncompatible(c.EIP155Block, newcfg.EIP155Block, head) {
+		return newCompatError("EIP155 fork block", c.EIP155Block, newcfg.EIP155Block)
+	}
+	if isForkIncompatible(c.EIP158Block, newcfg.EIP158Block, head) {
+		return newCompatError("EIP158 fork block", c.EIP158Block, newcfg.EIP158Block)
+	}
+	if c.IsEIP158(head) && !configNumEqual(c.ChainID, newcfg.ChainID) {
+		return newCompatError("EIP158 chain ID", c.EIP158Block, newcfg.EIP158Block)
+	}
+	if isForkIncompatible(c.ByzantiumBlock, newcfg.ByzantiumBlock, head) {
+		return newCompatError("Byzantium fork block", c.ByzantiumBlock, newcfg.ByzantiumBlock)
+	}
+	if isForkIncompatible(c.ConstantinopleBlock, newcfg.ConstantinopleBlock, head) {
+		return newCompatError("Constantinople fork block", c.ConstantinopleBlock, newcfg.ConstantinopleBlock)
+	}
+	if isForkIncompatible(c.PetersburgBlock, newcfg.PetersburgBlock, head) {
+		return newCompatError("Petersburg fork block", c.PetersburgBlock, newcfg.PetersburgBlock)
+	}
+	if isForkIncompatible(c.IstanbulBlock, newcfg.IstanbulBlock, head) {
+		return newCompatError("Istanbul fork block", c.IstanbulBlock, newcfg.IstanbulBlock)
+	}
+	if isForkIncompatible(c.EWASMBlock, newcfg.EWASMBlock, head) {
+		return newCompatError("ewasm fork block", c.EWASMBlock, newcfg.EWASMBlock)
+	}
+	return nil
+}
+
+// isForkIncompatible returns true if a fork scheduled at s1 cannot be rescheduled to
+// block s2 because head is already past the fork.
+func isForkIncompatible(s1, s2, head *big.Int) bool {
+	return (isForked(s1, head) || isForked(s2, head)) && !configNumEqual(s1, s2)
+}
+
+// isForked returns whether a fork scheduled at block s is active at the given head block.
+func isForked(s, head *big.Int) bool {
+	if s == nil || head == nil {
+		return false
+	}
+	return s.Cmp(head) <= 0
+}
+
+func configNumEqual(x, y *big.Int) bool {
+	if x == nil {
+		return y == nil
+	}
+	if y == nil {
+		return x == nil
+	}
+	return x.Cmp(y) == 0
+}
+
+// ConfigCompatError is raised if the locally-stored blockchain is initialised with a
+// ChainConfig that would alter the past.
+type ConfigCompatError struct {
+	What string
+	// block numbers of the stored and new configurations
+	StoredConfig, NewConfig *big.Int
+	// the block number to which the local chain must be rewound to correct the error
+	RewindTo uint64
+}
+
+func newCompatError(what string, storedblock, newblock *big.Int) *ConfigCompatError {
+	var rew *big.Int
+	switch {
+	case storedblock == nil:
+		rew = newblock
+	case newblock == nil || storedblock.Cmp(newblock) < 0:
+		rew = storedblock
+	default:
+		rew = newblock
+	}
+	err := &ConfigCompatError{what, storedblock, newblock, 0}
+	if rew != nil && rew.Sign() > 0 {
+		err.RewindTo = rew.Uint64() - 1
+	}
+	return err
+}
+
+func (err *ConfigCompatError) Error() string {
+	return fmt.Sprintf("mismatching %s in database (have %d, want %d, rewindto %d)", err.What, err.StoredConfig, err.NewConfig, err.RewindTo)
+}
+
+// Rules wraps ChainConfig and is merely syntactic sugar or can be used for functions
+// that do not have or require information about the block.
+//
+// Rules is a one time interface meaning that it shouldn't be used in between transition
+// phases.
+type Rules struct {
+	ChainID                                                 *big.Int
+	IsHomestead, IsEIP150, IsEIP155, IsEIP158               bool
+	IsByzantium, IsConstantinople, IsPetersburg, IsIstanbul bool
+}
+
+// Rules ensures c's ChainID is not nil.
+func (c *ChainConfig) Rules(num *big.Int) Rules {
+	chainID := c.ChainID
+	if chainID == nil {
+		chainID = new(big.Int)
+	}
+	return Rules{
+		ChainID:          new(big.Int).Set(chainID),
+		IsHomestead:      c.IsHomestead(num),
+		IsEIP150:         c.IsEIP150(num),
+		IsEIP155:         c.IsEIP155(num),
+		IsEIP158:         c.IsEIP158(num),
+		IsByzantium:      c.IsByzantium(num),
+		IsConstantinople: c.IsConstantinople(num),
+		IsPetersburg:     c.IsPetersburg(num),
+		IsIstanbul:       c.IsIstanbul(num),
+	}
+}