Merge 44f20203b8 into aa1e052cb4

cmd/geth/dao_test.go

@@ -0,0 +1,232 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package main
+
+import (
+	"io/ioutil"
+	"math/big"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/params"
+)
+
+// Genesis block for nodes which don't care about the DAO fork (i.e. not configured)
+var daoOldGenesis = `{
+	"alloc"      : {},
+	"coinbase"   : "0x0000000000000000000000000000000000000000",
+	"difficulty" : "0x20000",
+	"extraData"  : "",
+	"gasLimit"   : "0x2fefd8",
+	"nonce"      : "0x0000000000000042",
+	"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"timestamp"  : "0x00",
+	"config"     : {}
+}`
+
+// Genesis block for nodes which actively oppose the DAO fork
+var daoNoForkGenesis = `{
+	"alloc"      : {},
+	"coinbase"   : "0x0000000000000000000000000000000000000000",
+	"difficulty" : "0x20000",
+	"extraData"  : "",
+	"gasLimit"   : "0x2fefd8",
+	"nonce"      : "0x0000000000000042",
+	"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"timestamp"  : "0x00",
+	"config"     : {
+		"daoForkBlock"   : 314,
+		"daoForkSupport" : false
+	}
+}`
+
+// Genesis block for nodes which actively support the DAO fork
+var daoProForkGenesis = `{
+	"alloc"      : {},
+	"coinbase"   : "0x0000000000000000000000000000000000000000",
+	"difficulty" : "0x20000",
+	"extraData"  : "",
+	"gasLimit"   : "0x2fefd8",
+	"nonce"      : "0x0000000000000042",
+	"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+	"timestamp"  : "0x00",
+	"config"     : {
+		"daoForkBlock"   : 314,
+		"daoForkSupport" : true
+	}
+}`
+
+var daoGenesisHash = common.HexToHash("5e1fc79cb4ffa4739177b5408045cd5d51c6cf766133f23f7cd72ee1f8d790e0")
+var daoGenesisForkBlock = big.NewInt(314)
+
+// Tests that the DAO hard-fork number and the nodes support/opposition is correctly
+// set in the database after various initialization procedures and invocations.
+func TestDAODefaultMainnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, "", [][2]bool{{false, false}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAOSupportMainnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, "", [][2]bool{{true, false}}, params.MainNetDAOForkBlock, true)
+}
+func TestDAOOpposeMainnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, "", [][2]bool{{false, true}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAOSwitchToSupportMainnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, "", [][2]bool{{false, true}, {true, false}}, params.MainNetDAOForkBlock, true)
+}
+func TestDAOSwitchToOpposeMainnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, "", [][2]bool{{true, false}, {false, true}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAODefaultTestnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, true, "", [][2]bool{{false, false}}, params.TestNetDAOForkBlock, false)
+}
+func TestDAOSupportTestnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, true, "", [][2]bool{{true, false}}, params.TestNetDAOForkBlock, true)
+}
+func TestDAOOpposeTestnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, true, "", [][2]bool{{false, true}}, params.TestNetDAOForkBlock, false)
+}
+func TestDAOSwitchToSupportTestnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, true, "", [][2]bool{{false, true}, {true, false}}, params.TestNetDAOForkBlock, true)
+}
+func TestDAOSwitchToOpposeTestnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, true, "", [][2]bool{{true, false}, {false, true}}, params.TestNetDAOForkBlock, false)
+}
+func TestDAOInitOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{}, nil, false)
+}
+func TestDAODefaultOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{{false, false}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAOSupportOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{{true, false}}, params.MainNetDAOForkBlock, true)
+}
+func TestDAOOpposeOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{{false, true}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAOSwitchToSupportOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{{false, true}, {true, false}}, params.MainNetDAOForkBlock, true)
+}
+func TestDAOSwitchToOpposeOldPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoOldGenesis, [][2]bool{{true, false}, {false, true}}, params.MainNetDAOForkBlock, false)
+}
+func TestDAOInitNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{}, daoGenesisForkBlock, false)
+}
+func TestDAODefaultNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{{false, false}}, daoGenesisForkBlock, false)
+}
+func TestDAOSupportNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{{true, false}}, daoGenesisForkBlock, true)
+}
+func TestDAOOpposeNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{{false, true}}, daoGenesisForkBlock, false)
+}
+func TestDAOSwitchToSupportNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{{false, true}, {true, false}}, daoGenesisForkBlock, true)
+}
+func TestDAOSwitchToOpposeNoForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoNoForkGenesis, [][2]bool{{true, false}, {false, true}}, daoGenesisForkBlock, false)
+}
+func TestDAOInitProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{}, daoGenesisForkBlock, true)
+}
+func TestDAODefaultProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{{false, false}}, daoGenesisForkBlock, true)
+}
+func TestDAOSupportProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{{true, false}}, daoGenesisForkBlock, true)
+}
+func TestDAOOpposeProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{{false, true}}, daoGenesisForkBlock, false)
+}
+func TestDAOSwitchToSupportProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{{false, true}, {true, false}}, daoGenesisForkBlock, true)
+}
+func TestDAOSwitchToOpposeProForkPrivnet(t *testing.T) {
+	testDAOForkBlockNewChain(t, false, daoProForkGenesis, [][2]bool{{true, false}, {false, true}}, daoGenesisForkBlock, false)
+}
+
+func testDAOForkBlockNewChain(t *testing.T, testnet bool, genesis string, votes [][2]bool, expectBlock *big.Int, expectVote bool) {
+	// Create a temporary data directory to use and inspect later
+	datadir := tmpdir(t)
+	defer os.RemoveAll(datadir)
+
+	// Start a Geth instance with the requested flags set and immediately terminate
+	if genesis != "" {
+		json := filepath.Join(datadir, "genesis.json")
+		if err := ioutil.WriteFile(json, []byte(genesis), 0600); err != nil {
+			t.Fatalf("failed to write genesis file: %v", err)
+		}
+		runGeth(t, "--datadir", datadir, "init", json).cmd.Wait()
+	}
+	for _, vote := range votes {
+		args := []string{"--port", "0", "--maxpeers", "0", "--nodiscover", "--nat", "none", "--ipcdisable", "--datadir", datadir}
+		if testnet {
+			args = append(args, "--testnet")
+		}
+		if vote[0] {
+			args = append(args, "--support-dao-fork")
+		}
+		if vote[1] {
+			args = append(args, "--oppose-dao-fork")
+		}
+		geth := runGeth(t, append(args, []string{"--exec", "2+2", "console"}...)...)
+		geth.cmd.Wait()
+	}
+	// Retrieve the DAO config flag from the database
+	path := filepath.Join(datadir, "chaindata")
+	if testnet && genesis == "" {
+		path = filepath.Join(datadir, "testnet", "chaindata")
+	}
+	db, err := ethdb.NewLDBDatabase(path, 0, 0)
+	if err != nil {
+		t.Fatalf("failed to open test database: %v", err)
+	}
+	defer db.Close()
+
+	genesisHash := common.HexToHash("0xd4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3")
+	if testnet {
+		genesisHash = common.HexToHash("0x0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303")
+	}
+	if genesis != "" {
+		genesisHash = daoGenesisHash
+	}
+	config, err := core.GetChainConfig(db, genesisHash)
+	if err != nil {
+		t.Fatalf("failed to retrieve chain config: %v", err)
+	}
+	// Validate the DAO hard-fork block number against the expected value
+	if config.DAOForkBlock == nil {
+		if expectBlock != nil {
+			t.Errorf("dao hard-fork block mismatch: have nil, want %v", expectBlock)
+		}
+	} else if expectBlock == nil {
+		t.Errorf("dao hard-fork block mismatch: have %v, want nil", config.DAOForkBlock)
+	} else if config.DAOForkBlock.Cmp(expectBlock) != 0 {
+		t.Errorf("dao hard-fork block mismatch: have %v, want %v", config.DAOForkBlock, expectBlock)
+	}
+	if config.DAOForkSupport != expectVote {
+		t.Errorf("dao hard-fork support mismatch: have %v, want %v", config.DAOForkSupport, expectVote)
+	}
+}

cmd/geth/genesis_test.go

@@ -0,0 +1,107 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package main
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+var customGenesisTests = []struct {
+	genesis string
+	query   string
+	result  string
+}{
+	// Plain genesis file without anything extra
+	{
+		genesis: `{
+			"alloc"      : {},
+			"coinbase"   : "0x0000000000000000000000000000000000000000",
+			"difficulty" : "0x20000",
+			"extraData"  : "",
+			"gasLimit"   : "0x2fefd8",
+			"nonce"      : "0x0000000000000042",
+			"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"timestamp"  : "0x00"
+		}`,
+		query:  "eth.getBlock(0).nonce",
+		result: "0x0000000000000042",
+	},
+	// Genesis file with an empty chain configuration (ensure missing fields work)
+	{
+		genesis: `{
+			"alloc"      : {},
+			"coinbase"   : "0x0000000000000000000000000000000000000000",
+			"difficulty" : "0x20000",
+			"extraData"  : "",
+			"gasLimit"   : "0x2fefd8",
+			"nonce"      : "0x0000000000000042",
+			"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"timestamp"  : "0x00",
+			"config"     : {}
+		}`,
+		query:  "eth.getBlock(0).nonce",
+		result: "0x0000000000000042",
+	},
+	// Genesis file with specific chain configurations
+	{
+		genesis: `{
+			"alloc"      : {},
+			"coinbase"   : "0x0000000000000000000000000000000000000000",
+			"difficulty" : "0x20000",
+			"extraData"  : "",
+			"gasLimit"   : "0x2fefd8",
+			"nonce"      : "0x0000000000000042",
+			"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
+			"timestamp"  : "0x00",
+			"config"     : {
+				"homesteadBlock" : 314,
+				"daoForkBlock"   : 141,
+				"daoForkSupport" : true
+			},
+		}`,
+		query:  "eth.getBlock(0).nonce",
+		result: "0x0000000000000042",
+	},
+}
+
+// Tests that initializing Geth with a custom genesis block and chain definitions
+// work properly.
+func TestCustomGenesis(t *testing.T) {
+	for i, tt := range customGenesisTests {
+		// Create a temporary data directory to use and inspect later
+		datadir := tmpdir(t)
+		defer os.RemoveAll(datadir)
+
+		// Initialize the data directory with the custom genesis block
+		json := filepath.Join(datadir, "genesis.json")
+		if err := ioutil.WriteFile(json, []byte(tt.genesis), 0600); err != nil {
+			t.Fatalf("test %d: failed to write genesis file: %v", i, err)
+		}
+		runGeth(t, "--datadir", datadir, "init", json).cmd.Wait()
+
+		// Query the custom genesis block
+		geth := runGeth(t, "--datadir", datadir, "--maxpeers", "0", "--nodiscover", "--nat", "none", "--ipcdisable", "--exec", tt.query, "console")
+		geth.expectRegexp(tt.result)
+		geth.expectExit()
+	}
+}

cmd/geth/main.go

@@ -150,7 +150,6 @@ participating.
 		utils.IdentityFlag,
 		utils.UnlockedAccountFlag,
 		utils.PasswordFileFlag,
-		utils.GenesisFileFlag,
 		utils.BootnodesFlag,
 		utils.DataDirFlag,
 		utils.KeyStoreDirFlag,
@@ -165,6 +164,8 @@ participating.
 		utils.MaxPendingPeersFlag,
 		utils.EtherbaseFlag,
 		utils.GasPriceFlag,
+		utils.SupportDAOFork,
+		utils.OpposeDAOFork,
 		utils.MinerThreadsFlag,
 		utils.MiningEnabledFlag,
 		utils.MiningGPUFlag,
@@ -225,12 +226,6 @@ participating.
 		eth.EnableBadBlockReporting = true
 
 		utils.SetupNetwork(ctx)
-
-		// Deprecation warning.
-		if ctx.GlobalIsSet(utils.GenesisFileFlag.Name) {
-			common.PrintDepricationWarning("--genesis is deprecated. Switch to use 'geth init /path/to/file'")
-		}
-
 		return nil
 	}
 

cmd/geth/usage.go

@@ -68,7 +68,6 @@ var AppHelpFlagGroups = []flagGroup{
 			utils.OlympicFlag,
 			utils.TestNetFlag,
 			utils.DevModeFlag,
-			utils.GenesisFileFlag,
 			utils.IdentityFlag,
 			utils.FastSyncFlag,
 			utils.LightKDFFlag,

cmd/utils/flags.go

@@ -126,10 +126,6 @@ var (
 		Name:  "dev",
 		Usage: "Developer mode: pre-configured private network with several debugging flags",
 	}
-	GenesisFileFlag = cli.StringFlag{
-		Name:  "genesis",
-		Usage: "Insert/overwrite the genesis block (JSON format)",
-	}
 	IdentityFlag = cli.StringFlag{
 		Name:  "identity",
 		Usage: "Custom node name",
@@ -161,6 +157,15 @@ var (
 		Name:  "lightkdf",
 		Usage: "Reduce key-derivation RAM & CPU usage at some expense of KDF strength",
 	}
+	// Fork settings
+	SupportDAOFork = cli.BoolFlag{
+		Name:  "support-dao-fork",
+		Usage: "Updates the chain rules to support the DAO hard-fork",
+	}
+	OpposeDAOFork = cli.BoolFlag{
+		Name:  "oppose-dao-fork",
+		Usage: "Updates the chain rules to oppose the DAO hard-fork",
+	}
 	// Miner settings
 	// TODO: refactor CPU vs GPU mining flags
 	MiningEnabledFlag = cli.BoolFlag{
@@ -534,20 +539,6 @@ func MakeWSRpcHost(ctx *cli.Context) string {
 	return ctx.GlobalString(WSListenAddrFlag.Name)
 }
 
-// MakeGenesisBlock loads up a genesis block from an input file specified in the
-// command line, or returns the empty string if none set.
-func MakeGenesisBlock(ctx *cli.Context) string {
-	genesis := ctx.GlobalString(GenesisFileFlag.Name)
-	if genesis == "" {
-		return ""
-	}
-	data, err := ioutil.ReadFile(genesis)
-	if err != nil {
-		Fatalf("Failed to load custom genesis file: %v", err)
-	}
-	return string(data)
-}
-
 // MakeDatabaseHandles raises out the number of allowed file handles per process
 // for Geth and returns half of the allowance to assign to the database.
 func MakeDatabaseHandles() int {
@@ -689,7 +680,6 @@ func MakeSystemNode(name, version string, relconf release.Config, extra []byte,
 
 	ethConf := &eth.Config{
 		ChainConfig:             MustMakeChainConfig(ctx),
-		Genesis:                 MakeGenesisBlock(ctx),
 		FastSync:                ctx.GlobalBool(FastSyncFlag.Name),
 		BlockChainVersion:       ctx.GlobalInt(BlockchainVersionFlag.Name),
 		DatabaseCache:           ctx.GlobalInt(CacheFlag.Name),
@@ -722,17 +712,13 @@ func MakeSystemNode(name, version string, relconf release.Config, extra []byte,
 		if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
 			ethConf.NetworkId = 1
 		}
-		if !ctx.GlobalIsSet(GenesisFileFlag.Name) {
 		ethConf.Genesis = core.OlympicGenesisBlock()
-		}
 
 	case ctx.GlobalBool(TestNetFlag.Name):
 		if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
 			ethConf.NetworkId = 2
 		}
-		if !ctx.GlobalIsSet(GenesisFileFlag.Name) {
 		ethConf.Genesis = core.TestNetGenesisBlock()
-		}
 		state.StartingNonce = 1048576 // (2**20)
 
 	case ctx.GlobalBool(DevModeFlag.Name):
@@ -747,9 +733,7 @@ func MakeSystemNode(name, version string, relconf release.Config, extra []byte,
 			stackConf.ListenAddr = ":0"
 		}
 		// Override the Ethereum protocol configs
-		if !ctx.GlobalIsSet(GenesisFileFlag.Name) {
 		ethConf.Genesis = core.OlympicGenesisBlock()
-		}
 		if !ctx.GlobalIsSet(GasPriceFlag.Name) {
 			ethConf.GasPrice = new(big.Int)
 		}
@@ -813,24 +797,43 @@ func MustMakeChainConfig(ctx *cli.Context) *core.ChainConfig {
 
 // MustMakeChainConfigFromDb reads the chain configuration from the given database.
 func MustMakeChainConfigFromDb(ctx *cli.Context, db ethdb.Database) *core.ChainConfig {
-	genesis := core.GetBlock(db, core.GetCanonicalHash(db, 0), 0)
+	// If the chain is already initialized, use any existing chain configs
+	config := new(core.ChainConfig)
 
-	if genesis != nil {
+	if genesis := core.GetBlock(db, core.GetCanonicalHash(db, 0), 0); genesis != nil {
-		// Existing genesis block, use stored config if available.
 		storedConfig, err := core.GetChainConfig(db, genesis.Hash())
-		if err == nil {
+		switch err {
-			return storedConfig
+		case nil:
-		} else if err != core.ChainConfigNotFoundErr {
+			config = storedConfig
+		case core.ChainConfigNotFoundErr:
+			// No configs found, use empty, will populate below
+		default:
 			Fatalf("Could not make chain configuration: %v", err)
 		}
 	}
-	var homesteadBlockNo *big.Int
+	// Set any missing fields due to them being unset or system upgrade
+	if config.HomesteadBlock == nil {
 		if ctx.GlobalBool(TestNetFlag.Name) {
-		homesteadBlockNo = params.TestNetHomesteadBlock
+			config.HomesteadBlock = new(big.Int).Set(params.TestNetHomesteadBlock)
 		} else {
-		homesteadBlockNo = params.MainNetHomesteadBlock
+			config.HomesteadBlock = new(big.Int).Set(params.MainNetHomesteadBlock)
 		}
-	return &core.ChainConfig{HomesteadBlock: homesteadBlockNo}
+	}
+	if config.DAOForkBlock == nil {
+		if ctx.GlobalBool(TestNetFlag.Name) {
+			config.DAOForkBlock = new(big.Int).Set(params.TestNetDAOForkBlock)
+		} else {
+			config.DAOForkBlock = new(big.Int).Set(params.MainNetDAOForkBlock)
+		}
+	}
+	// Force override any existing configs if explicitly requested
+	switch {
+	case ctx.GlobalBool(SupportDAOFork.Name):
+		config.DAOForkSupport = true
+	case ctx.GlobalBool(OpposeDAOFork.Name):
+		config.DAOForkSupport = false
+	}
+	return config
 }
 
 // MakeChainDatabase open an LevelDB using the flags passed to the client and will hard crash if it fails.

core/block_validator.go

@@ -17,6 +17,7 @@
 package core
 
 import (
+	"bytes"
 	"fmt"
 	"math/big"
 	"time"
@@ -247,6 +248,33 @@ func ValidateHeader(config *ChainConfig, pow pow.PoW, header *types.Header, pare
 			return &BlockNonceErr{header.Number, header.Hash(), header.Nonce.Uint64()}
 		}
 	}
+	// If all checks passed, validate the extra-data field for hard forks
+	return ValidateHeaderExtraData(config, header)
+}
+
+// ValidateHeaderExtraData validates the extra-data field of a block header to
+// ensure it conforms to hard-fork rules.
+func ValidateHeaderExtraData(config *ChainConfig, header *types.Header) error {
+	// 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.
+	if daoBlock := config.DAOForkBlock; daoBlock != nil {
+		// Check whether the block is among the fork extra-override range
+		limit := new(big.Int).Add(daoBlock, params.DAOForkExtraRange)
+		if daoBlock.Cmp(header.Number) <= 0 && header.Number.Cmp(limit) < 0 {
+			// Depending whether we support or oppose the fork, verrift the extra-data contents
+			if config.DAOForkSupport {
+				if bytes.Compare(header.Extra, params.DAOForkBlockExtra) != 0 {
+					return ValidationError("DAO pro-fork bad block extra-data: 0x%x", header.Extra)
+				}
+			} else {
+				if bytes.Compare(header.Extra, params.DAOForkBlockExtra) == 0 {
+					return ValidationError("DAO no-fork bad block extra-data: 0x%x", header.Extra)
+				}
+			}
+		}
+	}
 	return nil
 }
 

core/block_validator_test.go

@@ -27,6 +27,7 @@ import (
 	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/pow/ezp"
 )
 
@@ -92,3 +93,107 @@ func TestPutReceipt(t *testing.T) {
 		t.Error("expected to get 1 receipt, got none.")
 	}
 }
+
+// Tests that DAO-fork enabled clients can properly filter out fork-commencing
+// blocks based on their extradata fields.
+func TestDAOForkRangeExtradata(t *testing.T) {
+	forkBlock := big.NewInt(32)
+
+	// Generate a common prefix for both pro-forkers and non-forkers
+	db, _ := ethdb.NewMemDatabase()
+	genesis := WriteGenesisBlockForTesting(db)
+	prefix, _ := GenerateChain(genesis, db, int(forkBlock.Int64()-1), func(i int, gen *BlockGen) {})
+
+	// Create the concurrent, conflicting two nodes
+	proDb, _ := ethdb.NewMemDatabase()
+	WriteGenesisBlockForTesting(proDb)
+	proBc, _ := NewBlockChain(proDb, &ChainConfig{HomesteadBlock: big.NewInt(0), DAOForkBlock: forkBlock, DAOForkSupport: true}, new(FakePow), new(event.TypeMux))
+
+	conDb, _ := ethdb.NewMemDatabase()
+	WriteGenesisBlockForTesting(conDb)
+	conBc, _ := NewBlockChain(conDb, &ChainConfig{HomesteadBlock: big.NewInt(0), DAOForkBlock: forkBlock, DAOForkSupport: false}, new(FakePow), new(event.TypeMux))
+
+	if _, err := proBc.InsertChain(prefix); err != nil {
+		t.Fatalf("pro-fork: failed to import chain prefix: %v", err)
+	}
+	if _, err := conBc.InsertChain(prefix); err != nil {
+		t.Fatalf("con-fork: failed to import chain prefix: %v", err)
+	}
+	// Try to expand both pro-fork and non-fork chains iteratively with other camp's blocks
+	for i := int64(0); i < params.DAOForkExtraRange.Int64(); i++ {
+		// Create a pro-fork block, and try to feed into the no-fork chain
+		db, _ = ethdb.NewMemDatabase()
+		WriteGenesisBlockForTesting(db)
+		bc, _ := NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))
+
+		blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()+1))
+		for j := 0; j < len(blocks)/2; j++ {
+			blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
+		}
+		if _, err := bc.InsertChain(blocks); err != nil {
+			t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
+		}
+		blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
+		if _, err := conBc.InsertChain(blocks); err == nil {
+			t.Fatalf("contra-fork chain accepted pro-fork block: %v", blocks[0])
+		}
+		// Create a proper no-fork block for the contra-forker
+		blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
+		if _, err := conBc.InsertChain(blocks); err != nil {
+			t.Fatalf("contra-fork chain didn't accepted no-fork block: %v", err)
+		}
+		// Create a no-fork block, and try to feed into the pro-fork chain
+		db, _ = ethdb.NewMemDatabase()
+		WriteGenesisBlockForTesting(db)
+		bc, _ = NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))
+
+		blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()+1))
+		for j := 0; j < len(blocks)/2; j++ {
+			blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
+		}
+		if _, err := bc.InsertChain(blocks); err != nil {
+			t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
+		}
+		blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
+		if _, err := proBc.InsertChain(blocks); err == nil {
+			t.Fatalf("pro-fork chain accepted contra-fork block: %v", blocks[0])
+		}
+		// Create a proper pro-fork block for the pro-forker
+		blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
+		if _, err := proBc.InsertChain(blocks); err != nil {
+			t.Fatalf("pro-fork chain didn't accepted pro-fork block: %v", err)
+		}
+	}
+	// Verify that contra-forkers accept pro-fork extra-datas after forking finishes
+	db, _ = ethdb.NewMemDatabase()
+	WriteGenesisBlockForTesting(db)
+	bc, _ := NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))
+
+	blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()+1))
+	for j := 0; j < len(blocks)/2; j++ {
+		blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
+	}
+	if _, err := bc.InsertChain(blocks); err != nil {
+		t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
+	}
+	blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
+	if _, err := conBc.InsertChain(blocks); err != nil {
+		t.Fatalf("contra-fork chain didn't accept pro-fork block post-fork: %v", err)
+	}
+	// Verify that pro-forkers accept contra-fork extra-datas after forking finishes
+	db, _ = ethdb.NewMemDatabase()
+	WriteGenesisBlockForTesting(db)
+	bc, _ = NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))
+
+	blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()+1))
+	for j := 0; j < len(blocks)/2; j++ {
+		blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
+	}
+	if _, err := bc.InsertChain(blocks); err != nil {
+		t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
+	}
+	blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
+	if _, err := proBc.InsertChain(blocks); err != nil {
+		t.Fatalf("pro-fork chain didn't accept contra-fork block post-fork: %v", err)
+	}
+}

core/config.go

@@ -31,16 +31,17 @@ var ChainConfigNotFoundErr = errors.New("ChainConfig not found") // general conf
 // that any network, identified by its genesis block, can have its own
 // set of configuration options.
 type ChainConfig struct {
-	HomesteadBlock *big.Int // homestead switch block
+	HomesteadBlock *big.Int `json:"homesteadBlock"` // Homestead switch block (nil = no fork, 0 = already homestead)
+	DAOForkBlock   *big.Int `json:"daoForkBlock"`   // TheDAO hard-fork switch block (nil = no fork)
+	DAOForkSupport bool     `json:"daoForkSupport"` // Whether the nodes supports or opposes the DAO hard-fork
 
 	VmConfig vm.Config `json:"-"`
 }
 
 // IsHomestead returns whether num is either equal to the homestead block or greater.
 func (c *ChainConfig) IsHomestead(num *big.Int) bool {
-	if num == nil {
+	if c.HomesteadBlock == nil || num == nil {
 		return false
 	}
-
 	return num.Cmp(c.HomesteadBlock) >= 0
 }

eth/backend.go

@@ -205,6 +205,8 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 	if config.ChainConfig == nil {
 		return nil, errors.New("missing chain config")
 	}
+	core.WriteChainConfig(chainDb, genesis.Hash(), config.ChainConfig)
+
 	eth.chainConfig = config.ChainConfig
 	eth.chainConfig.VmConfig = vm.Config{
 		EnableJit: config.EnableJit,

eth/handler.go

@@ -45,6 +45,10 @@ const (
 	estHeaderRlpSize  = 500             // Approximate size of an RLP encoded block header
 )
 
+var (
+	daoChallengeTimeout = 15 * time.Second // Time allowance for a node to reply to the DAO handshake challenge
+)
+
 // errIncompatibleConfig is returned if the requested protocols and configs are
 // not compatible (low protocol version restrictions and high requirements).
 var errIncompatibleConfig = errors.New("incompatible configuration")
@@ -65,6 +69,7 @@ type ProtocolManager struct {
 	txpool      txPool
 	blockchain  *core.BlockChain
 	chaindb     ethdb.Database
+	chainconfig *core.ChainConfig
 
 	downloader *downloader.Downloader
 	fetcher    *fetcher.Fetcher
@@ -99,6 +104,7 @@ func NewProtocolManager(config *core.ChainConfig, fastSync bool, networkId int,
 		txpool:      txpool,
 		blockchain:  blockchain,
 		chaindb:     chaindb,
+		chainconfig: config,
 		peers:       newPeerSet(),
 		newPeerCh:   make(chan *peer),
 		noMorePeers: make(chan struct{}),
@@ -278,6 +284,18 @@ func (pm *ProtocolManager) handle(p *peer) error {
 	// after this will be sent via broadcasts.
 	pm.syncTransactions(p)
 
+	// If we're DAO hard-fork aware, validate any remote peer with regard to the hard-fork
+	if daoBlock := pm.chainconfig.DAOForkBlock; daoBlock != nil {
+		// Request the peer's DAO fork header for extra-data validation
+		if err := p.RequestHeadersByNumber(daoBlock.Uint64(), 1, 0, false); err != nil {
+			return err
+		}
+		// Start a timer to disconnect if the peer doesn't reply in time
+		p.forkDrop = time.AfterFunc(daoChallengeTimeout, func() {
+			glog.V(logger.Warn).Infof("%v: timed out DAO fork-check, dropping", p)
+			pm.removePeer(p.id)
+		})
+	}
 	// main loop. handle incoming messages.
 	for {
 		if err := pm.handleMsg(p); err != nil {
@@ -481,9 +499,43 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		if err := msg.Decode(&headers); err != nil {
 			return errResp(ErrDecode, "msg %v: %v", msg, err)
 		}
+		// If no headers were received, but we're expending a DAO fork check, maybe it's that
+		if len(headers) == 0 && p.forkDrop != nil {
+			// Possibly an empty reply to the fork header checks, sanity check TDs
+			verifyDAO := true
+
+			// If we already have a DAO header, we can check the peer's TD against it. If
+			// the peer's ahead of this, it too must have a reply to the DAO check
+			if daoHeader := pm.blockchain.GetHeaderByNumber(pm.chainconfig.DAOForkBlock.Uint64()); daoHeader != nil {
+				if p.Td().Cmp(pm.blockchain.GetTd(daoHeader.Hash(), daoHeader.Number.Uint64())) >= 0 {
+					verifyDAO = false
+				}
+			}
+			// If we're seemingly on the same chain, disable the drop timer
+			if verifyDAO {
+				glog.V(logger.Info).Infof("%v: seems to be on the same side of the DAO fork", p)
+				p.forkDrop.Stop()
+				p.forkDrop = nil
+				return nil
+			}
+		}
 		// Filter out any explicitly requested headers, deliver the rest to the downloader
 		filter := len(headers) == 1
 		if filter {
+			// If it's a potential DAO fork check, validate against the rules
+			if p.forkDrop != nil && pm.chainconfig.DAOForkBlock.Cmp(headers[0].Number) == 0 {
+				// Disable the fork drop timer
+				p.forkDrop.Stop()
+				p.forkDrop = nil
+
+				// Validate the header and either drop the peer or continue
+				if err := core.ValidateHeaderExtraData(pm.chainconfig, headers[0]); err != nil {
+					glog.V(logger.Info).Infof("%v: verified to be on the other side of the DAO fork, dropping", p)
+					return err
+				}
+				glog.V(logger.Info).Infof("%v: verified to be on the same side of the DAO fork", p)
+			}
+			// Irrelevant of the fork checks, send the header to the fetcher just in case
 			headers = pm.fetcher.FilterHeaders(headers, time.Now())
 		}
 		if len(headers) > 0 || !filter {

eth/handler_test.go

@@ -20,6 +20,7 @@ import (
 	"math/big"
 	"math/rand"
 	"testing"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -28,6 +29,7 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/params"
 )
@@ -580,3 +582,74 @@ func testGetReceipt(t *testing.T, protocol int) {
 		t.Errorf("receipts mismatch: %v", err)
 	}
 }
+
+// Tests that post eth protocol handshake, DAO fork-enabled clients also execute
+// a DAO "challenge" verifying each others' DAO fork headers to ensure they're on
+// compatible chains.
+func TestDAOChallengeNoVsNo(t *testing.T)       { testDAOChallenge(t, false, false, false) }
+func TestDAOChallengeNoVsPro(t *testing.T)      { testDAOChallenge(t, false, true, false) }
+func TestDAOChallengeProVsNo(t *testing.T)      { testDAOChallenge(t, true, false, false) }
+func TestDAOChallengeProVsPro(t *testing.T)     { testDAOChallenge(t, true, true, false) }
+func TestDAOChallengeNoVsTimeout(t *testing.T)  { testDAOChallenge(t, false, false, true) }
+func TestDAOChallengeProVsTimeout(t *testing.T) { testDAOChallenge(t, true, true, true) }
+
+func testDAOChallenge(t *testing.T, localForked, remoteForked bool, timeout bool) {
+	// Reduce the DAO handshake challenge timeout
+	if timeout {
+		defer func(old time.Duration) { daoChallengeTimeout = old }(daoChallengeTimeout)
+		daoChallengeTimeout = 500 * time.Millisecond
+	}
+	// Create a DAO aware protocol manager
+	var (
+		evmux         = new(event.TypeMux)
+		pow           = new(core.FakePow)
+		db, _         = ethdb.NewMemDatabase()
+		genesis       = core.WriteGenesisBlockForTesting(db)
+		config        = &core.ChainConfig{DAOForkBlock: big.NewInt(1), DAOForkSupport: localForked}
+		blockchain, _ = core.NewBlockChain(db, config, pow, evmux)
+	)
+	pm, err := NewProtocolManager(config, false, NetworkId, evmux, new(testTxPool), pow, blockchain, db)
+	if err != nil {
+		t.Fatalf("failed to start test protocol manager: %v", err)
+	}
+	pm.Start()
+	defer pm.Stop()
+
+	// Connect a new peer and check that we receive the DAO challenge
+	peer, _ := newTestPeer("peer", eth63, pm, true)
+	defer peer.close()
+
+	challenge := &getBlockHeadersData{
+		Origin:  hashOrNumber{Number: config.DAOForkBlock.Uint64()},
+		Amount:  1,
+		Skip:    0,
+		Reverse: false,
+	}
+	if err := p2p.ExpectMsg(peer.app, GetBlockHeadersMsg, challenge); err != nil {
+		t.Fatalf("challenge mismatch: %v", err)
+	}
+	// Create a block to reply to the challenge if no timeout is simualted
+	if !timeout {
+		blocks, _ := core.GenerateChain(genesis, db, 1, func(i int, block *core.BlockGen) {
+			if remoteForked {
+				block.SetExtra(params.DAOForkBlockExtra)
+			}
+		})
+		if err := p2p.Send(peer.app, BlockHeadersMsg, []*types.Header{blocks[0].Header()}); err != nil {
+			t.Fatalf("failed to answer challenge: %v", err)
+		}
+	} else {
+		// Otherwise wait until the test timeout passes
+		time.Sleep(daoChallengeTimeout + 500*time.Millisecond)
+	}
+	// Verify that depending on fork side, the remote peer is maintained or dropped
+	if localForked == remoteForked && !timeout {
+		if peers := pm.peers.Len(); peers != 1 {
+			t.Fatalf("peer count mismatch: have %d, want %d", peers, 1)
+		}
+	} else {
+		if peers := pm.peers.Len(); peers != 0 {
+			t.Fatalf("peer count mismatch: have %d, want %d", peers, 0)
+		}
+	}
+}

eth/peer.go

@@ -60,6 +60,8 @@ type peer struct {
 	rw p2p.MsgReadWriter
 
 	version  int         // Protocol version negotiated
+	forkDrop *time.Timer // Timed connection dropper if forks aren't validated in time
+
 	head common.Hash
 	td   *big.Int
 	lock sync.RWMutex

miner/worker.go

@@ -17,6 +17,7 @@
 package miner
 
 import (
+	"bytes"
 	"fmt"
 	"math/big"
 	"sync"
@@ -33,6 +34,7 @@ import (
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
+	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/pow"
 	"gopkg.in/fatih/set.v0"
 )
@@ -468,7 +470,19 @@ func (self *worker) commitNewWork() {
 		Extra:      self.extra,
 		Time:       big.NewInt(tstamp),
 	}
-
+	// If we are care about TheDAO hard-fork check whether to override the extra-data or not
+	if daoBlock := self.config.DAOForkBlock; daoBlock != nil {
+		// Check whether the block is among the fork extra-override range
+		limit := new(big.Int).Add(daoBlock, params.DAOForkExtraRange)
+		if daoBlock.Cmp(header.Number) <= 0 && header.Number.Cmp(limit) < 0 {
+			// Depending whether we support or oppose the fork, override differently
+			if self.config.DAOForkSupport {
+				header.Extra = common.CopyBytes(params.DAOForkBlockExtra)
+			} else if bytes.Compare(header.Extra, params.DAOForkBlockExtra) == 0 {
+				header.Extra = []byte{} // If miner opposes, don't let it use the reserved extra-data
+			}
+		}
+	}
 	previous := self.current
 	// Could potentially happen if starting to mine in an odd state.
 	err := self.makeCurrent(parent, header)

params/util.go

@@ -16,9 +16,18 @@
 
 package params
 
-import "math/big"
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+)
 
 var (
-	TestNetHomesteadBlock = big.NewInt(494000)  // testnet homestead block
+	TestNetHomesteadBlock = big.NewInt(494000)  // Testnet homestead block
-	MainNetHomesteadBlock = big.NewInt(1150000) // mainnet homestead block
+	MainNetHomesteadBlock = big.NewInt(1150000) // Mainnet homestead block
+
+	TestNetDAOForkBlock = big.NewInt(8888888)                            // Testnet dao hard-fork block
+	MainNetDAOForkBlock = big.NewInt(9999999)                            // Mainnet dao hard-fork block
+	DAOForkBlockExtra   = common.FromHex("0x64616f2d686172642d666f726b") // Block extradata to signel the fork with ("dao-hard-fork")
+	DAOForkExtraRange   = big.NewInt(10)                                 // Number of blocks to override the extradata (prevent no-fork attacks)
 )