feat(core): implement EIP-2935 #29465 #30924 (#2033)

common/big.go

@@ -16,7 +16,11 @@
 
 package common
 
-import "math/big"
+import (
+	"math/big"
+
+	"github.com/holiman/uint256"
+)
 
 // Common big integers often used
 var (
@@ -27,4 +31,6 @@ var (
 	Big32  = big.NewInt(32)
 	Big256 = big.NewInt(256)
 	Big257 = big.NewInt(257)
+
+	U2560 = uint256.NewInt(0)
 )

core/chain_makers.go

@@ -193,7 +193,7 @@ func (b *BlockGen) OffsetTime(seconds int64) {
 	if b.header.Time <= b.parent.Header().Time {
 		panic("block time out of range")
 	}
-	chainReader := &fakeChainReader{config: b.config}
+	chainReader := &fakeChainReader{config: b.config, engine: b.engine}
 	b.header.Difficulty = b.engine.CalcDifficulty(chainReader, b.header.Time, b.parent.Header())
 }
 
@@ -214,7 +214,7 @@ func GenerateChain(config *params.ChainConfig, parent *types.Block, engine conse
 		config = params.TestChainConfig
 	}
 	blocks, receipts := make(types.Blocks, n), make([]types.Receipts, n)
-	chainReader := &fakeChainReader{config: config}
+	chainReader := &fakeChainReader{config: config, engine: engine}
 	genblock := func(i int, parent *types.Block, statedb *state.StateDB) (*types.Block, types.Receipts) {
 		b := &BlockGen{i: i, parent: parent, chain: blocks, statedb: statedb, config: config, engine: engine}
 		b.header = makeHeader(chainReader, parent, statedb, b.engine)
@@ -231,10 +231,19 @@ func GenerateChain(config *params.ChainConfig, parent *types.Block, engine conse
 		if config.DAOForkSupport && config.DAOForkBlock != nil && config.DAOForkBlock.Cmp(b.header.Number) == 0 {
 			misc.ApplyDAOHardFork(statedb)
 		}
-		// Execute any user modifications to the block and finalize it
+
+		if config.IsPrague(b.header.Number) {
+			// EIP-2935
+			blockContext := NewEVMBlockContext(b.header, chainReader, &b.header.Coinbase)
+			evm := vm.NewEVM(blockContext, vm.TxContext{}, statedb, nil, config, vm.Config{})
+			ProcessParentBlockHash(b.header.ParentHash, evm, statedb)
+		}
+
+		// Execute any user modifications to the block
 		if gen != nil {
 			gen(i, b)
 		}
+
 		if b.engine != nil {
 			// Finalize and seal the block
 			block, _ := b.engine.Finalize(chainReader, b.header, statedb, statedb.Copy(), b.txs, b.uncles, b.receipts)
@@ -323,6 +332,7 @@ func makeBlockChain(parent *types.Block, n int, engine consensus.Engine, db ethd
 
 type fakeChainReader struct {
 	config *params.ChainConfig
+	engine consensus.Engine
 }
 
 // Config returns the chain configuration.
@@ -330,6 +340,7 @@ func (cr *fakeChainReader) Config() *params.ChainConfig {
 	return cr.config
 }
 
+func (cr *fakeChainReader) Engine() consensus.Engine                                { return cr.engine }
 func (cr *fakeChainReader) CurrentHeader() *types.Header                            { return nil }
 func (cr *fakeChainReader) GetHeaderByNumber(number uint64) *types.Header           { return nil }
 func (cr *fakeChainReader) GetHeaderByHash(hash common.Hash) *types.Header          { return nil }

core/genesis.go

@@ -465,8 +465,7 @@ func DefaultDevnetGenesisBlock() *Genesis {
 	}
 }
 
-// DeveloperGenesisBlock returns the 'geth --dev' genesis block. Note, this must
+// DeveloperGenesisBlock returns the 'geth --dev' genesis block.
-// be seeded with the
 func DeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis {
 	// Override the default period to the user requested one
 	config := *params.AllXDPoSProtocolChanges
@@ -489,6 +488,8 @@ func DeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis {
 			common.BytesToAddress([]byte{7}): {Balance: big.NewInt(1)}, // ECScalarMul
 			common.BytesToAddress([]byte{8}): {Balance: big.NewInt(1)}, // ECPairing
 			faucet:                           {Balance: new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(9))},
+			// Pre-deploy system contracts
+			params.HistoryStorageAddress: {Nonce: 1, Code: params.HistoryStorageCode, Balance: common.Big0},
 		},
 	}
 }

core/state_processor.go

@@ -17,6 +17,8 @@
 package core
 
 import (
+	"bytes"
+	"encoding/binary"
 	"fmt"
 	"math/big"
 	"runtime"
@@ -100,6 +102,10 @@ func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, tra
 	signer := types.MakeSigner(p.config, blockNumber)
 	coinbaseOwner := getCoinbaseOwner(p.bc, statedb, header, nil)
 
+	if p.config.IsPrague(block.Number()) {
+		ProcessParentBlockHash(block.ParentHash(), vmenv, tracingStateDB)
+	}
+
 	// Iterate over and process the individual transactions
 	for i, tx := range block.Transactions() {
 		// check denylist txs after hf
@@ -203,6 +209,10 @@ func (p *StateProcessor) ProcessBlockNoValidator(cBlock *CalculatedBlock, stated
 	signer := types.MakeSigner(p.config, blockNumber)
 	coinbaseOwner := getCoinbaseOwner(p.bc, statedb, header, nil)
 
+	if p.config.IsPrague(block.Number()) {
+		ProcessParentBlockHash(block.ParentHash(), vmenv, tracingStateDB)
+	}
+
 	// Iterate over and process the individual transactions
 	receipts = make([]*types.Receipt, block.Transactions().Len())
 	for i, tx := range block.Transactions() {
@@ -639,3 +649,95 @@ func InitSignerInTransactions(config *params.ChainConfig, header *types.Header,
 	}
 	wg.Wait()
 }
+
+// ProcessParentBlockHash writes the parent hash to the EIP-2935 history contract
+// and enforces the expected code, with a one-time Prague backfill if missing.
+func ProcessParentBlockHash(prevHash common.Hash, vmenv *vm.EVM, statedb vm.StateDB) {
+	// Verify history contract code matches the expected bytecode
+	code := statedb.GetCode(params.HistoryStorageAddress)
+	if len(code) > 0 && !bytes.Equal(code, params.HistoryStorageCode) {
+		log.Error("History storage code mismatch",
+			"have", crypto.Keccak256Hash(code),
+			"want", crypto.Keccak256Hash(params.HistoryStorageCode),
+		)
+		panic("history storage code mismatch")
+	}
+
+	blockNumber := vmenv.Context.BlockNumber
+	if blockNumber == nil || !vmenv.ChainConfig().IsPrague(blockNumber) {
+		return
+	}
+	forkBlock := vmenv.ChainConfig().PragueBlock
+	if forkBlock == nil {
+		forkBlock = common.PragueBlock
+	}
+	if forkBlock == nil || blockNumber.Cmp(forkBlock) < 0 {
+		return
+	}
+
+	// Only deploy and backfill if the contract is missing at/after Prague activation.
+	if len(code) == 0 {
+		if !statedb.Exist(params.HistoryStorageAddress) {
+			statedb.CreateAccount(params.HistoryStorageAddress)
+		}
+		if statedb.GetNonce(params.HistoryStorageAddress) == 0 {
+			statedb.SetNonce(params.HistoryStorageAddress, 1)
+		}
+		statedb.SetCode(params.HistoryStorageAddress, params.HistoryStorageCode)
+
+		if blockNumber.Sign() > 0 {
+			end := blockNumber.Uint64() - 1
+			start := end
+			if end+1 > params.HistoryServeWindow {
+				start = end + 1 - params.HistoryServeWindow
+			}
+			if forkBlock.Sign() > 0 {
+				forkStart := forkBlock.Uint64() - 1
+				if forkStart > start {
+					start = forkStart
+				}
+			}
+			for n := start; n <= end; n++ {
+				hash := vmenv.Context.GetHash(n)
+				if hash == (common.Hash{}) {
+					log.Debug("History backfill missing hash", "number", n)
+					continue
+				}
+				statedb.SetState(params.HistoryStorageAddress, historyStorageKey(n), hash)
+			}
+		}
+	}
+
+	if tracer := vmenv.Config.Tracer; tracer != nil {
+		if tracer.OnSystemCallStart != nil {
+			tracer.OnSystemCallStart()
+		}
+		if tracer.OnSystemCallEnd != nil {
+			defer tracer.OnSystemCallEnd()
+		}
+	}
+
+	msg := &Message{
+		From:      params.SystemAddress,
+		GasLimit:  30_000_000,
+		GasPrice:  common.Big0,
+		GasFeeCap: common.Big0,
+		GasTipCap: common.Big0,
+		To:        &params.HistoryStorageAddress,
+		Data:      prevHash.Bytes(),
+	}
+	vmenv.Reset(NewEVMTxContext(msg), statedb)
+	statedb.AddAddressToAccessList(params.HistoryStorageAddress)
+	_, _, err := vmenv.Call(vm.AccountRef(msg.From), *msg.To, msg.Data, 30_000_000, common.U2560)
+	if err != nil {
+		panic(err)
+	}
+	statedb.Finalise(true)
+}
+
+func historyStorageKey(number uint64) common.Hash {
+	ringIndex := number % params.HistoryServeWindow
+	var key common.Hash
+	binary.BigEndian.PutUint64(key[24:], ringIndex)
+	return key
+}

core/state_processor_test.go

@@ -18,6 +18,7 @@ package core
 
 import (
 	"crypto/ecdsa"
+	"encoding/binary"
 	"math"
 	"math/big"
 	"testing"
@@ -26,10 +27,12 @@ import (
 	"github.com/XinFinOrg/XDPoSChain/consensus"
 	"github.com/XinFinOrg/XDPoSChain/consensus/ethash"
 	"github.com/XinFinOrg/XDPoSChain/core/rawdb"
+	"github.com/XinFinOrg/XDPoSChain/core/state"
 	"github.com/XinFinOrg/XDPoSChain/core/tracing"
 	"github.com/XinFinOrg/XDPoSChain/core/types"
 	"github.com/XinFinOrg/XDPoSChain/core/vm"
 	"github.com/XinFinOrg/XDPoSChain/crypto"
+	"github.com/XinFinOrg/XDPoSChain/ethdb/memorydb"
 	"github.com/XinFinOrg/XDPoSChain/params"
 	"github.com/XinFinOrg/XDPoSChain/trie"
 	"github.com/holiman/uint256"
@@ -318,7 +321,7 @@ func GenerateBadBlock(t *testing.T, parent *types.Block, engine consensus.Engine
 	header := &types.Header{
 		ParentHash: parent.Hash(),
 		Coinbase:   parent.Coinbase(),
-		Difficulty: engine.CalcDifficulty(&fakeChainReader{config}, parent.Time()+10, &types.Header{
+		Difficulty: engine.CalcDifficulty(&fakeChainReader{config: config, engine: engine}, parent.Time()+10, &types.Header{
 			Number:     parent.Number(),
 			Time:       parent.Time(),
 			Difficulty: parent.Difficulty(),
@@ -489,3 +492,146 @@ func TestApplyTransactionWithEVMTracer(t *testing.T) {
 		})
 	}
 }
+
+func TestProcessParentBlockHash(t *testing.T) {
+	var (
+		chainConfig = params.MergedTestChainConfig
+		hashA       = common.Hash{0x01}
+		hashB       = common.Hash{0x02}
+		header      = &types.Header{ParentHash: hashA, Number: big.NewInt(2), Difficulty: big.NewInt(0)}
+		parent      = &types.Header{ParentHash: hashB, Number: big.NewInt(1), Difficulty: big.NewInt(0)}
+		coinbase    = common.Address{}
+	)
+	test := func(statedb *state.StateDB) {
+		statedb.SetNonce(params.HistoryStorageAddress, 1)
+		statedb.SetCode(params.HistoryStorageAddress, params.HistoryStorageCode)
+		statedb.IntermediateRoot(true)
+
+		vmContext := NewEVMBlockContext(header, nil, &coinbase)
+		evm := vm.NewEVM(vmContext, vm.TxContext{}, statedb, nil, chainConfig, vm.Config{})
+		ProcessParentBlockHash(header.ParentHash, evm, statedb)
+
+		vmContext = NewEVMBlockContext(parent, nil, &coinbase)
+		evm = vm.NewEVM(vmContext, vm.TxContext{}, statedb, nil, chainConfig, vm.Config{})
+		ProcessParentBlockHash(parent.ParentHash, evm, statedb)
+
+		// make sure that the state is correct
+		if have := getParentBlockHash(statedb, 1); have != hashA {
+			t.Errorf("want parent hash %v, have %v", hashA, have)
+		}
+		if have := getParentBlockHash(statedb, 0); have != hashB {
+			t.Errorf("want parent hash %v, have %v", hashB, have)
+		}
+	}
+	t.Run("MPT", func(t *testing.T) {
+		statedb, _ := state.New(types.EmptyRootHash, state.NewDatabase(rawdb.NewDatabase(memorydb.New())))
+		test(statedb)
+	})
+}
+
+func TestProcessParentBlockHashPragueGuard(t *testing.T) {
+	config := *params.MergedTestChainConfig
+	config.PragueBlock = big.NewInt(10)
+
+	statedb, _ := state.New(types.EmptyRootHash, state.NewDatabase(rawdb.NewDatabase(memorydb.New())))
+	blockNumber := big.NewInt(5)
+	random := common.Hash{}
+	blockContext := vm.BlockContext{
+		CanTransfer: CanTransfer,
+		Transfer:    Transfer,
+		GetHash:     func(uint64) common.Hash { return common.Hash{} },
+		Coinbase:    common.Address{},
+		BlockNumber: blockNumber,
+		Time:        0,
+		Difficulty:  big.NewInt(0),
+		GasLimit:    0,
+		BaseFee:     nil,
+		Random:      &random,
+	}
+	evmenv := vm.NewEVM(blockContext, vm.TxContext{}, statedb, nil, &config, vm.Config{})
+	ProcessParentBlockHash(common.Hash{0x01}, evmenv, statedb)
+
+	if code := statedb.GetCode(params.HistoryStorageAddress); len(code) != 0 {
+		t.Fatalf("unexpected history contract code predeploy: %x", code)
+	}
+	if have := getParentBlockHash(statedb, 0); have != (common.Hash{}) {
+		t.Fatalf("expected empty history slot, have %v", have)
+	}
+}
+
+func TestProcessParentBlockHashBackfillMissingHistory(t *testing.T) {
+	config := *params.MergedTestChainConfig
+	statedb, _ := state.New(types.EmptyRootHash, state.NewDatabase(rawdb.NewDatabase(memorydb.New())))
+	blockNumber := big.NewInt(int64(params.HistoryServeWindow + 1))
+	available := map[uint64]common.Hash{
+		1:   {0x11},
+		100: {0x22},
+	}
+
+	random := common.Hash{}
+	blockContext := vm.BlockContext{
+		CanTransfer: CanTransfer,
+		Transfer:    Transfer,
+		GetHash: func(n uint64) common.Hash {
+			if hash, ok := available[n]; ok {
+				return hash
+			}
+			return common.Hash{}
+		},
+		Coinbase:    common.Address{},
+		BlockNumber: blockNumber,
+		Time:        0,
+		Difficulty:  big.NewInt(0),
+		GasLimit:    0,
+		BaseFee:     nil,
+		Random:      &random,
+	}
+	evmenv := vm.NewEVM(blockContext, vm.TxContext{}, statedb, nil, &config, vm.Config{})
+	ProcessParentBlockHash(common.Hash{0x01}, evmenv, statedb)
+
+	if have := getParentBlockHash(statedb, 1); have != available[1] {
+		t.Fatalf("expected hash at slot 1, have %v", have)
+	}
+	if have := getParentBlockHash(statedb, 100); have != available[100] {
+		t.Fatalf("expected hash at slot 100, have %v", have)
+	}
+	if have := getParentBlockHash(statedb, 2); have != (common.Hash{}) {
+		t.Fatalf("expected empty history slot, have %v", have)
+	}
+}
+
+func TestProcessParentBlockHashCodeMismatchPanics(t *testing.T) {
+	config := *params.MergedTestChainConfig
+	statedb, _ := state.New(types.EmptyRootHash, state.NewDatabase(rawdb.NewDatabase(memorydb.New())))
+	statedb.SetCode(params.HistoryStorageAddress, []byte{0x01})
+
+	blockNumber := big.NewInt(1)
+	random := common.Hash{}
+	blockContext := vm.BlockContext{
+		CanTransfer: CanTransfer,
+		Transfer:    Transfer,
+		GetHash:     func(uint64) common.Hash { return common.Hash{} },
+		Coinbase:    common.Address{},
+		BlockNumber: blockNumber,
+		Time:        0,
+		Difficulty:  big.NewInt(0),
+		GasLimit:    0,
+		BaseFee:     nil,
+		Random:      &random,
+	}
+	evmenv := vm.NewEVM(blockContext, vm.TxContext{}, statedb, nil, &config, vm.Config{})
+
+	defer func() {
+		if recover() == nil {
+			t.Fatal("expected panic on history storage code mismatch")
+		}
+	}()
+	ProcessParentBlockHash(common.Hash{0x01}, evmenv, statedb)
+}
+
+func getParentBlockHash(statedb *state.StateDB, number uint64) common.Hash {
+	ringIndex := number % params.HistoryServeWindow
+	var key common.Hash
+	binary.BigEndian.PutUint64(key[24:], ringIndex)
+	return statedb.GetState(params.HistoryStorageAddress, key)
+}

docs/README.md

@@ -4,3 +4,4 @@
 - [Validator Contract](xdc/validator.md)
 - [Development environment](develop.md)
 - [Solidity](solidity.md)
+- [Upgrade notes](upgrade.md)

docs/upgrade.md

@@ -0,0 +1,8 @@
+# Upgrade Notes
+
+## Prague / EIP-2935
+
+- The history storage contract is predeployed only in the developer genesis.
+- For other networks, the contract is deployed at Prague activation by the system call during block processing and state access.
+- Nodes upgrading after Prague will perform a one-time backfill of recent parent hashes into the ring buffer. If historical headers are pruned or unavailable, missing slots are skipped and only available hashes are filled.
+- If you maintain a custom genesis and want predeployment, add an account entry for `HistoryStorageAddress` with `Nonce: 1` and `Code: HistoryStorageCode`.

eth/state_accessor.go

@@ -206,6 +206,12 @@ func (eth *Ethereum) stateAtTransaction(ctx context.Context, block *types.Block,
 	if err != nil {
 		return nil, vm.BlockContext{}, nil, nil, err
 	}
+	// If prague hardfork, insert parent block hash in the state as per EIP-2935.
+	if eth.blockchain.Config().IsPrague(block.Number()) {
+		context := core.NewEVMBlockContext(block.Header(), eth.blockchain, nil)
+		vmenv := vm.NewEVM(context, vm.TxContext{}, statedb, nil, eth.blockchain.Config(), vm.Config{})
+		core.ProcessParentBlockHash(block.ParentHash(), vmenv, statedb)
+	}
 	if txIndex == 0 && len(block.Transactions()) == 0 {
 		return nil, vm.BlockContext{}, statedb, release, nil
 	}

eth/tracers/api.go

@@ -379,6 +379,12 @@ func (api *API) traceChain(start, end *types.Block, config *TraceConfig, closed
 				failed = err
 				break
 			}
+			// Insert parent hash in history contract.
+			if api.backend.ChainConfig().IsPrague(next.Number()) {
+				context := core.NewEVMBlockContext(next.Header(), api.chainContext(ctx), nil)
+				vmenv := vm.NewEVM(context, vm.TxContext{}, statedb, nil, api.backend.ChainConfig(), vm.Config{})
+				core.ProcessParentBlockHash(next.ParentHash(), vmenv, statedb)
+			}
 			// Clean out any pending release functions of trace state. Note this
 			// step must be done after constructing tracing state, because the
 			// tracing state of block next depends on the parent state and construction
@@ -513,6 +519,9 @@ func (api *API) IntermediateRoots(ctx context.Context, hash common.Hash, config
 		vmctx              = core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil)
 		deleteEmptyObjects = chainConfig.IsEIP158(block.Number())
 	)
+	if chainConfig.IsPrague(block.Number()) {
+		core.ProcessParentBlockHash(block.ParentHash(), vm.NewEVM(vmctx, vm.TxContext{}, statedb, nil, chainConfig, vm.Config{}), statedb)
+	}
 	feeCapacity := statedb.GetTRC21FeeCapacityFromState()
 	for i, tx := range block.Transactions() {
 		if err := ctx.Err(); err != nil {
@@ -593,6 +602,10 @@ func (api *API) traceBlock(ctx context.Context, block *types.Block, config *Trac
 		signer    = types.MakeSigner(api.backend.ChainConfig(), block.Number())
 		results   = make([]*txTraceResult, len(txs))
 	)
+	if api.backend.ChainConfig().IsPrague(block.Number()) {
+		vmenv := vm.NewEVM(blockCtx, vm.TxContext{}, statedb, nil, api.backend.ChainConfig(), vm.Config{})
+		core.ProcessParentBlockHash(block.ParentHash(), vmenv, statedb)
+	}
 	feeCapacity := statedb.GetTRC21FeeCapacityFromState()
 	for i, tx := range txs {
 		var balance *big.Int

miner/worker.go

@@ -787,6 +787,11 @@ func (w *worker) commitNewWork() {
 	if common.TIPSigning.Cmp(header.Number) == 0 {
 		work.state.DeleteAddress(common.BlockSignersBinary)
 	}
+	if w.config.IsPrague(header.Number) {
+		context := core.NewEVMBlockContext(header, w.chain, nil)
+		vmenv := vm.NewEVM(context, vm.TxContext{}, w.current.state, nil, w.config, vm.Config{})
+		core.ProcessParentBlockHash(header.ParentHash, vmenv, w.current.state)
+	}
 	// won't grasp txs at checkpoint
 	var (
 		txs                                                                  *transactionsByPriceAndNonce

params/protocol_params.go

@@ -16,7 +16,11 @@
 
 package params
 
-import "math/big"
+import (
+	"math/big"
+
+	"github.com/XinFinOrg/XDPoSChain/common"
+)
 
 const (
 	GasLimitBoundDivisor uint64 = 1024               // The bound divisor of the gas limit, used in update calculations.
@@ -160,6 +164,8 @@ const (
 	Bn256PairingBaseGasIstanbul      uint64 = 45000  // Base price for an elliptic curve pairing check
 	Bn256PairingPerPointGasByzantium uint64 = 80000  // Byzantium per-point price for an elliptic curve pairing check
 	Bn256PairingPerPointGasIstanbul  uint64 = 34000  // Per-point price for an elliptic curve pairing check
+
+	HistoryServeWindow = 8191 // Number of blocks to serve historical block hashes for, EIP-2935.
 )
 
 var (
@@ -170,3 +176,13 @@ var (
 
 	TargetGasLimit uint64 = XDCGenesisGasLimit // The artificial target
 )
+
+// System contracts.
+var (
+	// SystemAddress is where the system-transaction is sent from as per EIP-2935
+	SystemAddress = common.HexToAddress("0xfffffffffffffffffffffffffffffffffffffffe")
+
+	// EIP-2935 - Serve historical block hashes from state
+	HistoryStorageAddress = common.HexToAddress("0x0000F90827F1C53a10cb7A02335B175320002935")
+	HistoryStorageCode    = common.FromHex("3373fffffffffffffffffffffffffffffffffffffffe14604657602036036042575f35600143038111604257611fff81430311604257611fff9006545f5260205ff35b5f5ffd5b5f35611fff60014303065500")
+)