path: root/core/genesis.go

// Copyright 2014 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 core

import (
	"bytes"
	"encoding/hex"
	"encoding/json"
	"errors"
	"fmt"
	"math/big"
	"strings"

	"github.com/ava-labs/coreth/core/rawdb"
	"github.com/ava-labs/coreth/core/state"
	"github.com/ava-labs/coreth/core/types"
	"github.com/ava-labs/coreth/params"
	"github.com/ava-labs/go-ethereum/common"
	"github.com/ava-labs/go-ethereum/common/hexutil"
	"github.com/ava-labs/go-ethereum/common/math"
	"github.com/ava-labs/go-ethereum/crypto"
	"github.com/ava-labs/go-ethereum/ethdb"
	"github.com/ava-labs/go-ethereum/log"
	"github.com/ava-labs/go-ethereum/rlp"
)

//go:generate gencodec -type Genesis -field-override genesisSpecMarshaling -out gen_genesis.go
//go:generate gencodec -type GenesisAccount -field-override genesisAccountMarshaling -out gen_genesis_account.go

var errGenesisNoConfig = errors.New("genesis has no chain configuration")

// Genesis specifies the header fields, state of a genesis block. It also defines hard
// fork switch-over blocks through the chain configuration.
type Genesis struct {
	Config     *params.ChainConfig `json:"config"`
	Nonce      uint64              `json:"nonce"`
	Timestamp  uint64              `json:"timestamp"`
	ExtraData  []byte              `json:"extraData"`
	GasLimit   uint64              `json:"gasLimit"   gencodec:"required"`
	Difficulty *big.Int            `json:"difficulty" gencodec:"required"`
	Mixhash    common.Hash         `json:"mixHash"`
	Coinbase   common.Address      `json:"coinbase"`
	Alloc      GenesisAlloc        `json:"alloc"      gencodec:"required"`

	// These fields are used for consensus tests. Please don't use them
	// in actual genesis blocks.
	Number     uint64      `json:"number"`
	GasUsed    uint64      `json:"gasUsed"`
	ParentHash common.Hash `json:"parentHash"`
}

// GenesisAlloc specifies the initial state that is part of the genesis block.
type GenesisAlloc map[common.Address]GenesisAccount

func (ga *GenesisAlloc) UnmarshalJSON(data []byte) error {
	m := make(map[common.UnprefixedAddress]GenesisAccount)
	if err := json.Unmarshal(data, &m); err != nil {
		return err
	}
	*ga = make(GenesisAlloc)
	for addr, a := range m {
		(*ga)[common.Address(addr)] = a
	}
	return nil
}

type GenesisMultiCoinBalance map[common.Hash]*big.Int

// GenesisAccount is an account in the state of the genesis block.
type GenesisAccount struct {
	Code       []byte                      `json:"code,omitempty"`
	Storage    map[common.Hash]common.Hash `json:"storage,omitempty"`
	Balance    *big.Int                    `json:"balance" gencodec:"required"`
	MCBalance  GenesisMultiCoinBalance     `json:"mcbalance,omitempty"`
	Nonce      uint64                      `json:"nonce,omitempty"`
	PrivateKey []byte                      `json:"secretKey,omitempty"` // for tests
}

// field type overrides for gencodec
type genesisSpecMarshaling struct {
	Nonce      math.HexOrDecimal64
	Timestamp  math.HexOrDecimal64
	ExtraData  hexutil.Bytes
	GasLimit   math.HexOrDecimal64
	GasUsed    math.HexOrDecimal64
	Number     math.HexOrDecimal64
	Difficulty *math.HexOrDecimal256
	Alloc      map[common.UnprefixedAddress]GenesisAccount
}

type genesisAccountMarshaling struct {
	Code       hexutil.Bytes
	Balance    *math.HexOrDecimal256
	Nonce      math.HexOrDecimal64
	Storage    map[storageJSON]storageJSON
	PrivateKey hexutil.Bytes
}

// storageJSON represents a 256 bit byte array, but allows less than 256 bits when
// unmarshaling from hex.
type storageJSON common.Hash

func (h *storageJSON) UnmarshalText(text []byte) error {
	text = bytes.TrimPrefix(text, []byte("0x"))
	if len(text) > 64 {
		return fmt.Errorf("too many hex characters in storage key/value %q", text)
	}
	offset := len(h) - len(text)/2 // pad on the left
	if _, err := hex.Decode(h[offset:], text); err != nil {
		fmt.Println(err)
		return fmt.Errorf("invalid hex storage key/value %q", text)
	}
	return nil
}

func (h storageJSON) MarshalText() ([]byte, error) {
	return hexutil.Bytes(h[:]).MarshalText()
}

// GenesisMismatchError is raised when trying to overwrite an existing
// genesis block with an incompatible one.
type GenesisMismatchError struct {
	Stored, New common.Hash
}

func (e *GenesisMismatchError) Error() string {
	return fmt.Sprintf("database contains incompatible genesis (have %x, new %x)", e.Stored, e.New)
}

// SetupGenesisBlock writes or updates the genesis block in db.
// The block that will be used is:
//
//                          genesis == nil       genesis != nil
//                       +------------------------------------------
//     db has no genesis |  main-net default  |  genesis
//     db has genesis    |  from DB           |  genesis (if compatible)
//
// The stored chain configuration will be updated if it is compatible (i.e. does not
// specify a fork block below the local head block). In case of a conflict, the
// error is a *params.ConfigCompatError and the new, unwritten config is returned.
//
// The returned chain configuration is never nil.
func SetupGenesisBlock(db ethdb.Database, genesis *Genesis) (*params.ChainConfig, common.Hash, error) {
	return SetupGenesisBlockWithOverride(db, genesis, nil)
}

func SetupGenesisBlockWithOverride(db ethdb.Database, genesis *Genesis, overrideIstanbul *big.Int) (*params.ChainConfig, common.Hash, error) {
	if genesis != nil && genesis.Config == nil {
		return params.AllEthashProtocolChanges, common.Hash{}, errGenesisNoConfig
	}
	// Just commit the new block if there is no stored genesis block.
	stored := rawdb.ReadCanonicalHash(db, 0)
	if (stored == common.Hash{}) {
		if genesis == nil {
			log.Info("Writing default main-net genesis block")
			genesis = DefaultGenesisBlock()
		} else {
			log.Info("Writing custom genesis block")
		}
		block, err := genesis.Commit(db)
		if err != nil {
			return genesis.Config, common.Hash{}, err
		}
		return genesis.Config, block.Hash(), nil
	}

	// We have the genesis block in database(perhaps in ancient database)
	// but the corresponding state is missing.
	header := rawdb.ReadHeader(db, stored, 0)
	if _, err := state.New(header.Root, state.NewDatabaseWithCache(db, 0)); err != nil {
		if genesis == nil {
			genesis = DefaultGenesisBlock()
		}
		// Ensure the stored genesis matches with the given one.
		hash := genesis.ToBlock(nil).Hash()
		if hash != stored {
			return genesis.Config, hash, &GenesisMismatchError{stored, hash}
		}
		block, err := genesis.Commit(db)
		if err != nil {
			return genesis.Config, hash, err
		}
		return genesis.Config, block.Hash(), nil
	}

	// Check whether the genesis block is already written.
	if genesis != nil {
		hash := genesis.ToBlock(nil).Hash()
		if hash != stored {
			return genesis.Config, hash, &GenesisMismatchError{stored, hash}
		}
	}

	// Get the existing chain configuration.
	newcfg := configOrDefault(genesis, stored)
	if overrideIstanbul != nil {
		newcfg.IstanbulBlock = overrideIstanbul
	}
	storedcfg := rawdb.ReadChainConfig(db, stored)
	if storedcfg == nil {
		log.Warn("Found genesis block without chain config")
		rawdb.WriteChainConfig(db, stored, newcfg)
		return newcfg, stored, nil
	}
	// Special case: don't change the existing config of a non-mainnet chain if no new
	// config is supplied. These chains would get AllProtocolChanges (and a compat error)
	// if we just continued here.
	if genesis == nil && stored != params.MainnetGenesisHash {
		return storedcfg, stored, nil
	}

	// Check config compatibility and write the config. Compatibility errors
	// are returned to the caller unless we're already at block zero.
	height := rawdb.ReadHeaderNumber(db, rawdb.ReadHeadHeaderHash(db))
	if height == nil {
		return newcfg, stored, fmt.Errorf("missing block number for head header hash")
	}
	compatErr := storedcfg.CheckCompatible(newcfg, *height)
	if compatErr != nil && *height != 0 && compatErr.RewindTo != 0 {
		return newcfg, stored, compatErr
	}
	rawdb.WriteChainConfig(db, stored, newcfg)
	return newcfg, stored, nil
}

func configOrDefault(g *Genesis, ghash common.Hash) *params.ChainConfig {
	switch {
	case g != nil:
		return g.Config
	case ghash == params.MainnetGenesisHash:
		return params.MainnetChainConfig
	case ghash == params.TestnetGenesisHash:
		return params.TestnetChainConfig
	default:
		return params.AllEthashProtocolChanges
	}
}

// ToBlock creates the genesis block and writes state of a genesis spec