path: root/eth/backend.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 eth implements the Ethereum protocol.
package eth

import (
    "bytes"
    "fmt"
    "math/big"
    "os"
    "path/filepath"
    "regexp"
    "strings"
    "time"

    "github.com/ethereum/ethash"
    "github.com/ethereum/go-ethereum/accounts"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/common/compiler"
    "github.com/ethereum/go-ethereum/common/httpclient"
    "github.com/ethereum/go-ethereum/core"
    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/eth/downloader"
    "github.com/ethereum/go-ethereum/ethdb"
    "github.com/ethereum/go-ethereum/event"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/logger/glog"
    "github.com/ethereum/go-ethereum/miner"
    "github.com/ethereum/go-ethereum/node"
    "github.com/ethereum/go-ethereum/p2p"
    "github.com/ethereum/go-ethereum/rlp"
)

const (
    epochLength    = 30000
    ethashRevision = 23

    autoDAGcheckInterval = 10 * time.Hour
    autoDAGepochHeight   = epochLength / 2
)

var (
    datadirInUseErrnos = map[uint]bool{11: true, 32: true, 35: true}
    portInUseErrRE     = regexp.MustCompile("address already in use")
)

type Config struct {
    NetworkId int    // Network ID to use for selecting peers to connect to
    Genesis   string // Genesis JSON to seed the chain database with
    FastSync  bool   // Enables the state download based fast synchronisation algorithm

    BlockChainVersion  int
    SkipBcVersionCheck bool // e.g. blockchain export
    DatabaseCache      int

    NatSpec   bool
    DocRoot   string
    AutoDAG   bool
    PowTest   bool
    ExtraData []byte

    AccountManager *accounts.Manager
    Etherbase      common.Address
    GasPrice       *big.Int
    MinerThreads   int
    SolcPath       string

    GpoMinGasPrice          *big.Int
    GpoMaxGasPrice          *big.Int
    GpoFullBlockRatio       int
    GpobaseStepDown         int
    GpobaseStepUp           int
    GpobaseCorrectionFactor int

    TestGenesisBlock *types.Block   // Genesis block to seed the chain database with (testing only!)
    TestGenesisState ethdb.Database // Genesis state to seed the database with (testing only!)
}

type Ethereum struct {
    // Channel for shutting down the ethereum
    shutdownChan chan bool

    // DB interfaces
    chainDb ethdb.Database // Block chain database
    dappDb  ethdb.Database // Dapp database

    // Handlers
    txPool          *core.TxPool
    blockchain      *core.BlockChain
    accountManager  *accounts.Manager
    pow             *ethash.Ethash
    protocolManager *ProtocolManager
    SolcPath        string
    solc            *compiler.Solidity

    GpoMinGasPrice          *big.Int
    GpoMaxGasPrice          *big.Int
    GpoFullBlockRatio       int
    GpobaseStepDown         int
    GpobaseStepUp           int
    GpobaseCorrectionFactor int

    httpclient *httpclient.HTTPClient

    eventMux *event.TypeMux
    miner    *miner.Miner

    Mining       bool
    MinerThreads int
    NatSpec      bool
    AutoDAG      bool
    PowTest      bool
    autodagquit  chan bool
    etherbase    common.Address
    netVersionId int
}

func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
    // Let the database take 3/4 of the max open files (TODO figure out a way to get the actual limit of the open files)
    const dbCount = 3
    ethdb.OpenFileLimit = 128 / (dbCount + 1)

    // Open the chain database and perform any upgrades needed
    chainDb, err := ctx.Database("chaindata", config.DatabaseCache)
    if err != nil {
        return nil, err
    }
    if db, ok := chainDb.(*ethdb.LDBDatabase); ok {
        db.Meter("eth/db/chaindata/")
    }
    if err := upgradeChainDatabase(chainDb); err != nil {
        return nil, err
    }
    if err := addMipmapBloomBins(chainDb); err != nil {
        return nil, err
    }

    dappDb, err := ctx.Database("dapp", config.DatabaseCache)
    if err != nil {
        return nil, err
    }
    if db, ok := dappDb.(*ethdb.LDBDatabase); ok {
        db.Meter("eth/db/dapp/")
    }
    glog.V(logger.Info).Infof("Protocol Versions: %v, Network Id: %v", ProtocolVersions, config.NetworkId)

    // Load up any custom genesis block if requested
    if len(config.Genesis) > 0 {
        block, err := core.WriteGenesisBlock(chainDb, strings.NewReader(config.Genesis))
        if err != nil {
            return nil, err
        }
        glog.V(logger.Info).Infof("Successfully wrote custom genesis block: %x", block.Hash())
    }
    // Load up a test setup if directly injected
    if config.TestGenesisState != nil {
        chainDb = config.TestGenesisState
    }
    if config.TestGenesisBlock != nil {
        core.WriteTd(chainDb, config.TestGenesisBlock.Hash(), config.TestGenesisBlock.Difficulty())
        core.WriteBlock(chainDb, config.TestGenesisBlock)
        core.WriteCanonicalHash(chainDb, config.TestGenesisBlock.Hash(), config.TestGenesisBlock.NumberU64())
        core.WriteHeadBlockHash(chainDb, config.TestGenesisBlock.Hash())
    }

    if !config.SkipBcVersionCheck {
        b, _ := chainDb.Get([]byte("BlockchainVersion"))
        bcVersion := int(common.NewValue(b).Uint())
        if bcVersion != config.BlockChainVersion && bcVersion != 0 {
            return nil, fmt.Errorf("Blockchain DB version mismatch (%d / %d). Run geth upgradedb.\n", bcVersion, config.BlockChainVersion)
        }
        saveBlockchainVersion(chainDb, config.BlockChainVersion)
    }
    glog.V(logger.Info).Infof("Blockchain DB Version: %d", config.BlockChainVersion)

    eth := &Ethereum{
        shutdownChan:            make(chan bool),
        chainDb:                 chainDb,
        dappDb:                  dappDb,
        eventMux:                &event.TypeMux{},
        accountManager:          config.AccountManager,
        etherbase:               config.Etherbase,
        netVersionId:            config.NetworkId,
        NatSpec:                 config.NatSpec,
        MinerThreads:            config.MinerThreads,
        SolcPath:                config.SolcPath,
        AutoDAG:                 config.AutoDAG,
        PowTest:                 config.PowTest,
        GpoMinGasPrice:          config.GpoMinGasPrice,
        GpoMaxGasPrice:          config.GpoMaxGasPrice,
        GpoFullBlockRatio:       config.GpoFullBlockRatio,
        GpobaseStepDown:         config.GpobaseStepDown,
        GpobaseStepUp:           config.GpobaseStepUp,
        GpobaseCorrectionFactor: config.GpobaseCorrectionFactor,
        httpclient:              httpclient.New(config.DocRoot),
    }

    if config.PowTest {
        glog.V(logger.Info).Infof("ethash used in test mode")
        eth.pow, err = ethash.NewForTesting()
        if err != nil {
            return nil, err
        }
    } else {
        eth.pow = ethash.New()
    }
    //genesis := core.GenesisBlock(uint64(config.GenesisNonce), stateDb)
    eth.blockchain, err = core.NewBlockChain(chainDb, eth.pow, eth.EventMux())
    if err != nil {
        if err == core.ErrNoGenesis {
            return nil, fmt.Errorf(`Genesis block not found. Please supply a genesis block with the "--genesis /path/to/file" argument`)
        }
        return nil, err
    }
    newPool := core.NewTxPool(eth.EventMux(), eth.blockchain.State, eth.blockchain.GasLimit)
    eth.txPool = newPool

    if eth.protocolManager, err = NewProtocolManager(config.FastSync, config.NetworkId, eth.eventMux, eth.txPool, eth.pow, eth.blockchain, chainDb); err != nil {
        return nil, err
    }
    eth.miner = miner.New(eth, eth.EventMux(), eth.pow)
    eth.miner.SetGasPrice(config.GasPrice)
    eth.miner.SetExtra(config.ExtraData)

    return eth, nil
}

func (s *Ethereum) ResetWithGenesisBlock(gb *types.Block) {
    s.blockchain.ResetWithGenesisBlock(gb)
}

func (s *Ethereum) Etherbase() (eb common.Address, err error) {
    eb = s.etherbase
    if (eb == common.Address{}) {
        addr, e := s.AccountManager().AddressByIndex(0)
        if e != nil {
            err = fmt.Errorf("etherbase address must be explicitly specified")
        }
        eb = common.HexToAddress(addr)
    }
    return
}

// set in js console via admin interface or wrapper from cli flags
func (self *Ethereum) SetEtherbase(etherbase common.Address) {
    self.etherbase = etherbase
    self.miner.SetEtherbase(etherbase)
}

func (s *Ethereum) StopMining()         { s.miner.Stop() }
func (s *Ethereum) IsMining() bool      { return s.miner.Mining() }
func (s *Ethereum) Miner() *miner.Miner { return s.miner }

func (s *Ethereum) AccountManager() *accounts.Manager  { return s.accountManager }
func (s *Ethereum) BlockChain() *core.BlockChain       { return s.blockchain }
func (s *Ethereum) TxPool() *core.TxPool               { return s.txPool }
func (s *Ethereum) EventMux() *event.TypeMux           { return s.eventMux }
func (s *Ethereum) ChainDb() ethdb.Database            { return s.chainDb }
func (s *Ethereum) DappDb() ethdb.Database             { return s.dappDb }
func (s *Ethereum) IsListening() bool                  { return true } // Always listening
func (s *Ethereum) EthVersion() int                    { return int(s.protocolManager.SubProtocols[0].Version) }
func (s *Ethereum) NetVersion() int                    { return s.netVersionId }
func (s *Ethereum) Downloader() *downloader.Downloader { return s.protocolManager.downloader }

// Protocols implements node.Service, returning all the currently configured
// network protocols to start.
func (s *Ethereum) Protocols() []p2p.Protocol {
    return s.protocolManager.SubProtocols
}

// Start implements node.Service, starting all internal goroutines needed by the
// Ethereum protocol implementation.
func (s *Ethereum) Start(*p2p.Server) error {
    if s.AutoDAG {
        s.StartAutoDAG()
    }
    s.protocolManager.Start()
    return nil
}

// Stop implements node.Service, terminating all internal goroutines used by the
// Ethereum protocol.
func (s *Ethereum) Stop() error {
    s.blockchain.Stop()
    s.protocolManager.Stop()
    s.txPool.Stop()
    s.eventMux.Stop()

    s.StopAutoDAG()

    s.chainDb.Close()
    s.dappDb.Close()
    close(s.shutdownChan)

    return nil
}

// This function will wait for a shutdown and resumes main thread execution
func (s *Ethereum) WaitForShutdown() {
    <-s.shutdownChan
}

// StartAutoDAG() spawns a go routine that checks the DAG every autoDAGcheckInterval
// by default that is 10 times per epoch
// in epoch n, if we past autoDAGepochHeight within-epoch blocks,
// it calls ethash.MakeDAG  to pregenerate the DAG for the next epoch n+1
// if it does not exist yet as well as remove the DAG for epoch n-1
// the loop quits if autodagquit channel is closed, it can safely restart and
// stop any number of times.
// For any more sophisticated pattern of DAG generation, use CLI subcommand
// makedag
func (self *Ethereum) StartAutoDAG() {
    if self.autodagquit != nil {
        return // already started
    }
    go func() {
        glog.V(logger.Info).Infof("Automatic pregeneration of ethash DAG ON (ethash dir: %s)", ethash.DefaultDir)
        var nextEpoch uint64
        timer := time.After(0)
        self.autodagquit = make(chan bool)
        for {
            select {
            case <-timer:
                glog.V(logger.Info).Infof("checking DAG (ethash dir: %s)", ethash.DefaultDir)
                currentBlock := self.BlockChain().CurrentBlock().NumberU64()
                thisEpoch := currentBlock / epochLength
                if nextEpoch <= thisEpoch {
                    if currentBlock%epochLength > autoDAGepochHeight {
                        if thisEpoch > 0 {
                            previousDag, previousDagFull := dagFiles(thisEpoch - 1)
                            os.Remove(filepath.Join(ethash.DefaultDir, previousDag))
                            os.Remove(filepath.Join(ethash.DefaultDir, previousDagFull))
                            glog.V(logger.Info).Infof("removed DAG for epoch %d (%s)", thisEpoch-1, previousDag)
                        }
                        nextEpoch = thisEpoch + 1
                        dag, _ := dagFiles(nextEpoch)
                        if _, err := os.Stat(dag); os.IsNotExist(err) {
                            glog.V(logger.Info).Infof("Pregenerating DAG for epoch %d (%s)", nextEpoch, dag)
                            err := ethash.MakeDAG(nextEpoch*epochLength, "") // "" -> ethash.DefaultDir
                            if err != nil {
                                glog.V(logger.Error).Infof("Error generating DAG for epoch %d (%s)", nextEpoch, dag)
                                return
                            }
                        } else {
                            glog.V(logger.Error).Infof("DAG for epoch %d (%s)", nextEpoch, dag)
                        }
                    }
                }
                timer = time.After(autoDAGcheckInterval)
            case <-self.autodagquit:
                return
            }
        }
    }()
}

// stopAutoDAG stops automatic DAG pregeneration by quitting the loop
func (self *Ethereum) StopAutoDAG() {
    if self.autodagquit != nil {
        close(self.autodagquit)
        self.autodagquit = nil
    }
    glog.V(logger.Info).Infof("Automatic pregeneration of ethash DAG OFF (ethash dir: %s)", ethash.DefaultDir)
}

// HTTPClient returns the light http client used for fetching offchain docs
// (natspec, source for verification)
func (self *Ethereum) HTTPClient() *httpclient.HTTPClient {
    return self.httpclient
}

func (self *Ethereum) Solc() (*compiler.Solidity, error) {
    var err error
    if self.solc == nil {
        self.solc, err = compiler.New(self.SolcPath)
    }
    return self.solc, err
}

// set in js console via admin interface or wrapper from cli flags
func (self *Ethereum) SetSolc(solcPath string) (*compiler.Solidity, error) {
    self.SolcPath = solcPath
    self.solc = nil
    return self.Solc()
}

// dagFiles(epoch) returns the two alternative DAG filenames (not a path)
// 1) <revision>-<hex(seedhash[8])> 2) full-R<revision>-<hex(seedhash[8])>
func dagFiles(epoch uint64) (string, string) {
    seedHash, _ := ethash.GetSeedHash(epoch * epochLength)
    dag := fmt.Sprintf("full-R%d-%x", ethashRevision, seedHash[:8])
    return dag, "full-R" + dag
}

func saveBlockchainVersion(db ethdb.Database, bcVersion int) {
    d, _ := db.Get([]byte("BlockchainVersion"))
    blockchainVersion := common.NewValue(d).Uint()

    if blockchainVersion == 0 {
        db.Put([]byte("BlockchainVersion"), common.NewValue(bcVersion).Bytes())
    }
}

// upgradeChainDatabase ensures that the chain database stores block split into
// separate header and body entries.
func upgradeChainDatabase(db ethdb.Database) error {
    // Short circuit if the head block is stored already as separate header and body
    data, err := db.Get([]byte("LastBlock"))
    if err != nil {
        return nil
    }
    head := common.BytesToHash(data)

    if block := core.GetBlockByHashOld(db, head); block == nil {
        return nil
    }
    // At least some of the database is still the old format, upgrade (skip the head block!)
    glog.V(logger.Info).Info("Old database detected, upgrading...")

    if db, ok := db.(*ethdb.LDBDatabase); ok {
        blockPrefix := []byte("block-hash-")
        for it := db.NewIterator(); it.Next(); {
            // Skip anything other than a combined block
            if !bytes.HasPrefix(it.Key(), blockPrefix) {
                continue
            }
            // Skip the head block (merge last to signal upgrade completion)
            if bytes.HasSuffix(it.Key(), head.Bytes()) {
                continue
            }
            // Load the block, split and serialize (order!)
            block := core.GetBlockByHashOld(db, common.BytesToHash(bytes.TrimPrefix(it.Key(), blockPrefix)))

            if err := core.WriteTd(db, block.Hash(), block.DeprecatedTd()); err != nil {
                return err
            }
            if err := core.WriteBody(db, block.Hash(), &types.Body{block.Transactions(), block.Uncles()}); err != nil {
                return err
            }
            if err := core.WriteHeader(db, block.Header()); err != nil {
                return err
            }
            if err := db.Delete(it.Key()); err != nil {
                return err
            }
        }
        // Lastly, upgrade the head block, disabling the upgrade mechanism
        current := core.GetBlockByHashOld(db, head)

        if err := core.WriteTd(db, current.Hash(), current.DeprecatedTd()); err != nil {
            return err
        }
        if err := core.WriteBody(db, current.Hash(), &types.Body{current.Transactions(), current.Uncles()}); err != nil {
            return err
        }
        if err := core.WriteHeader(db, current.Header()); err != nil {
            return err
        }
    }
    return nil
}

func addMipmapBloomBins(db ethdb.Database) (err error) {
    const mipmapVersion uint = 2

    // check if the version is set. We ignore data for now since there's
    // only one version so we can easily ignore it for now
    var data []byte
    data, _ = db.Get([]byte("setting-mipmap-version"))
    if len(data) > 0 {
        var version uint
        if err := rlp.DecodeBytes(data, &version); err == nil && version == mipmapVersion {
            return nil
        }
    }

    defer func() {
        if err == nil {
            var val []byte
            val, err = rlp.EncodeToBytes(mipmapVersion)
            if err == nil {
                err = db.Put([]byte("setting-mipmap-version"), val)
            }
            return
        }
    }()
    latestBlock := core.GetBlock(db, core.GetHeadBlockHash(db))
    if latestBlock == nil { // clean database
        return
    }

    tstart := time.Now()
    glog.V(logger.Info).Infoln("upgrading db log bloom bins")
    for i := uint64(0); i <= latestBlock.NumberU64(); i++ {
        hash := core.GetCanonicalHash(db, i)
        if (hash == common.Hash{}) {
            return fmt.Errorf("chain db corrupted. Could not find block %d.", i)
        }
        core.WriteMipmapBloom(db, i, core.GetBlockReceipts(db, hash))
    }
    glog.V(logger.Info).Infoln("upgrade completed in", time.Since(tstart))
    return nil
}