Revert "all: remove ethash pow, only retain shims needed for consensu…

…s and tests (ethereum#27178)"

This reverts commit 3eb5306.

cmd/devp2p/internal/ethtest/testdata/genesis.json

@@ -6,7 +6,6 @@
         "eip155Block": 0,
         "eip158Block": 0,
         "byzantiumBlock": 0,
-        "terminalTotalDifficultyPassed": true,
         "ethash": {}
     },
     "nonce": "0xdeadbeefdeadbeef",

cmd/evm/internal/t8ntool/block.go

@@ -28,6 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/common/math"
 	"github.com/ethereum/go-ethereum/consensus/clique"
+	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
@@ -73,9 +74,11 @@ type bbInput struct {
 	Withdrawals []*types.Withdrawal `json:"withdrawals,omitempty"`
 	Clique      *cliqueInput        `json:"clique,omitempty"`
 
-	Ethash bool                 `json:"-"`
-	Txs    []*types.Transaction `json:"-"`
-	Ommers []*types.Header      `json:"-"`
+	Ethash    bool                 `json:"-"`
+	EthashDir string               `json:"-"`
+	PowMode   ethash.Mode          `json:"-"`
+	Txs       []*types.Transaction `json:"-"`
+	Ommers    []*types.Header      `json:"-"`
 }
 
 type cliqueInput struct {
@@ -159,13 +162,42 @@ func (i *bbInput) ToBlock() *types.Block {
 // SealBlock seals the given block using the configured engine.
 func (i *bbInput) SealBlock(block *types.Block) (*types.Block, error) {
 	switch {
+	case i.Ethash:
+		return i.sealEthash(block)
 	case i.Clique != nil:
 		return i.sealClique(block)
 	default:
 		return block, nil
 	}
 }
 
+// sealEthash seals the given block using ethash.
+func (i *bbInput) sealEthash(block *types.Block) (*types.Block, error) {
+	if i.Header.Nonce != nil {
+		return nil, NewError(ErrorConfig, fmt.Errorf("sealing with ethash will overwrite provided nonce"))
+	}
+	ethashConfig := ethash.Config{
+		PowMode:        i.PowMode,
+		DatasetDir:     i.EthashDir,
+		CacheDir:       i.EthashDir,
+		DatasetsInMem:  1,
+		DatasetsOnDisk: 2,
+		CachesInMem:    2,
+		CachesOnDisk:   3,
+	}
+	engine := ethash.New(ethashConfig, nil, true)
+	defer engine.Close()
+	// Use a buffered chan for results.
+	// If the testmode is used, the sealer will return quickly, and complain
+	// "Sealing result is not read by miner" if it cannot write the result.
+	results := make(chan *types.Block, 1)
+	if err := engine.Seal(nil, block, results, nil); err != nil {
+		panic(fmt.Sprintf("failed to seal block: %v", err))
+	}
+	found := <-results
+	return block.WithSeal(found.Header()), nil
+}
+
 // sealClique seals the given block using clique.
 func (i *bbInput) sealClique(block *types.Block) (*types.Block, error) {
 	// If any clique value overwrites an explicit header value, fail
@@ -235,8 +267,28 @@ func readInput(ctx *cli.Context) (*bbInput, error) {
 		withdrawalsStr = ctx.String(InputWithdrawalsFlag.Name)
 		txsStr         = ctx.String(InputTxsRlpFlag.Name)
 		cliqueStr      = ctx.String(SealCliqueFlag.Name)
+		ethashOn       = ctx.Bool(SealEthashFlag.Name)
+		ethashDir      = ctx.String(SealEthashDirFlag.Name)
+		ethashMode     = ctx.String(SealEthashModeFlag.Name)
 		inputData      = &bbInput{}
 	)
+	if ethashOn && cliqueStr != "" {
+		return nil, NewError(ErrorConfig, fmt.Errorf("both ethash and clique sealing specified, only one may be chosen"))
+	}
+	if ethashOn {
+		inputData.Ethash = ethashOn
+		inputData.EthashDir = ethashDir
+		switch ethashMode {
+		case "normal":
+			inputData.PowMode = ethash.ModeNormal
+		case "test":
+			inputData.PowMode = ethash.ModeTest
+		case "fake":
+			inputData.PowMode = ethash.ModeFake
+		default:
+			return nil, NewError(ErrorConfig, fmt.Errorf("unknown pow mode: %s, supported modes: test, fake, normal", ethashMode))
+		}
+	}
 	if headerStr == stdinSelector || ommersStr == stdinSelector || txsStr == stdinSelector || cliqueStr == stdinSelector {
 		decoder := json.NewDecoder(os.Stdin)
 		if err := decoder.Decode(inputData); err != nil {

cmd/evm/internal/t8ntool/flags.go

@@ -125,6 +125,19 @@ var (
 		Name:  "seal.clique",
 		Usage: "Seal block with Clique. `stdin` or file name of where to find the Clique sealing data.",
 	}
+	SealEthashFlag = &cli.BoolFlag{
+		Name:  "seal.ethash",
+		Usage: "Seal block with ethash.",
+	}
+	SealEthashDirFlag = &cli.StringFlag{
+		Name:  "seal.ethash.dir",
+		Usage: "Path to ethash DAG. If none exists, a new DAG will be generated.",
+	}
+	SealEthashModeFlag = &cli.StringFlag{
+		Name:  "seal.ethash.mode",
+		Usage: "Defines the type and amount of PoW verification an ethash engine makes.",
+		Value: "normal",
+	}
 	RewardFlag = &cli.Int64Flag{
 		Name:  "state.reward",
 		Usage: "Mining reward. Set to -1 to disable",

cmd/evm/main.go

@@ -179,6 +179,9 @@ var blockBuilderCommand = &cli.Command{
 		t8ntool.InputWithdrawalsFlag,
 		t8ntool.InputTxsRlpFlag,
 		t8ntool.SealCliqueFlag,
+		t8ntool.SealEthashFlag,
+		t8ntool.SealEthashDirFlag,
+		t8ntool.SealEthashModeFlag,
 		t8ntool.VerbosityFlag,
 	},
 }

cmd/geth/genesis_test.go

@@ -41,9 +41,7 @@ var customGenesisTests = []struct {
 			"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
 			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
 			"timestamp"  : "0x00",
-			"config"     : {
-				"terminalTotalDifficultyPassed": true
-			}
+			"config"     : {}
 		}`,
 		query:  "eth.getBlock(0).nonce",
 		result: "0x0000000000001338",
@@ -61,10 +59,9 @@ var customGenesisTests = []struct {
 			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
 			"timestamp"  : "0x00",
 			"config"     : {
-				"homesteadBlock"                : 42,
-				"daoForkBlock"                  : 141,
-				"daoForkSupport"                : true,
-				"terminalTotalDifficultyPassed" : true
+				"homesteadBlock" : 42,
+				"daoForkBlock"   : 141,
+				"daoForkSupport" : true
 			}
 		}`,
 		query:  "eth.getBlock(0).nonce",
@@ -114,10 +111,8 @@ func TestCustomBackend(t *testing.T) {
 			"mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
 			"parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
 			"timestamp"  : "0x00",
-			"config"     : {
-				"terminalTotalDifficultyPassed": true
-			}
-		}`
+			"config"     : {}
+	}`
 	type backendTest struct {
 		initArgs   []string
 		initExpect string

cmd/geth/main.go

@@ -66,6 +66,14 @@ var (
 		utils.SmartCardDaemonPathFlag,
 		utils.OverrideCancun,
 		utils.EnablePersonal,
+		utils.EthashCacheDirFlag,
+		utils.EthashCachesInMemoryFlag,
+		utils.EthashCachesOnDiskFlag,
+		utils.EthashCachesLockMmapFlag,
+		utils.EthashDatasetDirFlag,
+		utils.EthashDatasetsInMemoryFlag,
+		utils.EthashDatasetsOnDiskFlag,
+		utils.EthashDatasetsLockMmapFlag,
 		utils.TxPoolLocalsFlag,
 		utils.TxPoolNoLocalsFlag,
 		utils.TxPoolJournalFlag,
@@ -112,11 +120,14 @@ var (
 		utils.MaxPeersFlag,
 		utils.MaxPendingPeersFlag,
 		utils.MiningEnabledFlag,
+		utils.MinerThreadsFlag,
+		utils.MinerNotifyFlag,
 		utils.MinerGasLimitFlag,
 		utils.MinerGasPriceFlag,
 		utils.MinerEtherbaseFlag,
 		utils.MinerExtraDataFlag,
 		utils.MinerRecommitIntervalFlag,
+		utils.MinerNoVerifyFlag,
 		utils.MinerNewPayloadTimeout,
 		utils.NATFlag,
 		utils.NoDiscoverFlag,
@@ -131,11 +142,13 @@ var (
 		utils.VMEnableDebugFlag,
 		utils.NetworkIdFlag,
 		utils.EthStatsURLFlag,
+		utils.FakePoWFlag,
 		utils.NoCompactionFlag,
 		utils.GpoBlocksFlag,
 		utils.GpoPercentileFlag,
 		utils.GpoMaxGasPriceFlag,
 		utils.GpoIgnoreGasPriceFlag,
+		utils.MinerNotifyFullFlag,
 		configFileFlag,
 	}, utils.NetworkFlags, utils.DatabasePathFlags)
 
@@ -211,6 +224,8 @@ func init() {
 		attachCommand,
 		javascriptCommand,
 		// See misccmd.go:
+		makecacheCommand,
+		makedagCommand,
 		versionCommand,
 		versionCheckCommand,
 		licenseCommand,
@@ -423,7 +438,9 @@ func startNode(ctx *cli.Context, stack *node.Node, backend ethapi.Backend, isCon
 		// Set the gas price to the limits from the CLI and start mining
 		gasprice := flags.GlobalBig(ctx, utils.MinerGasPriceFlag.Name)
 		ethBackend.TxPool().SetGasPrice(gasprice)
-		if err := ethBackend.StartMining(); err != nil {
+		// start mining
+		threads := ctx.Int(utils.MinerThreadsFlag.Name)
+		if err := ethBackend.StartMining(threads); err != nil {
 			utils.Fatalf("Failed to start mining: %v", err)
 		}
 	}

cmd/geth/misccmd.go

@@ -20,8 +20,11 @@ import (
 	"fmt"
 	"os"
 	"runtime"
+	"strconv"
 	"strings"
 
+	"github.com/ethereum/go-ethereum/cmd/utils"
+	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/internal/version"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/urfave/cli/v2"
@@ -38,6 +41,30 @@ var (
 		Usage: "Version to check",
 		Value: version.ClientName(clientIdentifier),
 	}
+	makecacheCommand = &cli.Command{
+		Action:    makecache,
+		Name:      "makecache",
+		Usage:     "Generate ethash verification cache (for testing)",
+		ArgsUsage: "<blockNum> <outputDir>",
+		Description: `
+The makecache command generates an ethash cache in <outputDir>.
+
+This command exists to support the system testing project.
+Regular users do not need to execute it.
+`,
+	}
+	makedagCommand = &cli.Command{
+		Action:    makedag,
+		Name:      "makedag",
+		Usage:     "Generate ethash mining DAG (for testing)",
+		ArgsUsage: "<blockNum> <outputDir>",
+		Description: `
+The makedag command generates an ethash DAG in <outputDir>.
+
+This command exists to support the system testing project.
+Regular users do not need to execute it.
+`,
+	}
 	versionCommand = &cli.Command{
 		Action:    printVersion,
 		Name:      "version",
@@ -69,6 +96,36 @@ and displays information about any security vulnerabilities that affect the curr
 	}
 )
 
+// makecache generates an ethash verification cache into the provided folder.
+func makecache(ctx *cli.Context) error {
+	args := ctx.Args().Slice()
+	if len(args) != 2 {
+		utils.Fatalf(`Usage: geth makecache <block number> <outputdir>`)
+	}
+	block, err := strconv.ParseUint(args[0], 0, 64)
+	if err != nil {
+		utils.Fatalf("Invalid block number: %v", err)
+	}
+	ethash.MakeCache(block, args[1])
+
+	return nil
+}
+
+// makedag generates an ethash mining DAG into the provided folder.
+func makedag(ctx *cli.Context) error {
+	args := ctx.Args().Slice()
+	if len(args) != 2 {
+		utils.Fatalf(`Usage: geth makedag <block number> <outputdir>`)
+	}
+	block, err := strconv.ParseUint(args[0], 0, 64)
+	if err != nil {
+		utils.Fatalf("Invalid block number: %v", err)
+	}
+	ethash.MakeDataset(block, args[1])
+
+	return nil
+}
+
 func printVersion(ctx *cli.Context) error {
 	git, _ := version.VCS()