core/forkid: skip genesis forks by time (#28034)

* core/forkid: skip genesis forks by time

* core/forkid: add comment about skipping non-zero fork times

* core/forkid: skip all time based forks in genesis using loop

* core/forkid: simplify logic for dropping time-based forks

Author: lightclient

cmd/devp2p/nodesetcmd.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/forkid"
 	"github.com/ethereum/go-ethereum/p2p/enr"
 	"github.com/ethereum/go-ethereum/params"
@@ -228,13 +229,13 @@ func ethFilter(args []string) (nodeFilter, error) {
 	var filter forkid.Filter
 	switch args[0] {
 	case "mainnet":
-		filter = forkid.NewStaticFilter(params.MainnetChainConfig, params.MainnetGenesisHash)
+		filter = forkid.NewStaticFilter(params.MainnetChainConfig, core.DefaultGenesisBlock().ToBlock())
 	case "goerli":
-		filter = forkid.NewStaticFilter(params.GoerliChainConfig, params.GoerliGenesisHash)
+		filter = forkid.NewStaticFilter(params.GoerliChainConfig, core.DefaultGoerliGenesisBlock().ToBlock())
 	case "sepolia":
-		filter = forkid.NewStaticFilter(params.SepoliaChainConfig, params.SepoliaGenesisHash)
+		filter = forkid.NewStaticFilter(params.SepoliaChainConfig, core.DefaultSepoliaGenesisBlock().ToBlock())
 	case "holesky":
-		filter = forkid.NewStaticFilter(params.HoleskyChainConfig, params.HoleskyGenesisHash)
+		filter = forkid.NewStaticFilter(params.HoleskyChainConfig, core.DefaultHoleskyGenesisBlock().ToBlock())
 	default:
 		return nil, fmt.Errorf("unknown network %q", args[0])
 	}

core/forkid/forkid.go

@@ -26,7 +26,6 @@ import (
 	"reflect"
 	"strings"
 
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
@@ -78,7 +77,7 @@ func NewID(config *params.ChainConfig, genesis *types.Block, head, time uint64)
 	hash := crc32.ChecksumIEEE(genesis.Hash().Bytes())
 
 	// Calculate the current fork checksum and the next fork block
-	forksByBlock, forksByTime := gatherForks(config)
+	forksByBlock, forksByTime := gatherForks(config, genesis.Time())
 	for _, fork := range forksByBlock {
 		if fork <= head {
 			// Fork already passed, checksum the previous hash and the fork number
@@ -88,10 +87,6 @@ func NewID(config *params.ChainConfig, genesis *types.Block, head, time uint64)
 		return ID{Hash: checksumToBytes(hash), Next: fork}
 	}
 	for _, fork := range forksByTime {
-		if fork <= genesis.Time() {
-			// Fork active in genesis, skip in forkid calculation
-			continue
-		}
 		if fork <= time {
 			// Fork already passed, checksum the previous hash and fork timestamp
 			hash = checksumUpdate(hash, fork)
@@ -119,7 +114,7 @@ func NewIDWithChain(chain Blockchain) ID {
 func NewFilter(chain Blockchain) Filter {
 	return newFilter(
 		chain.Config(),
-		chain.Genesis().Hash(),
+		chain.Genesis(),
 		func() (uint64, uint64) {
 			head := chain.CurrentHeader()
 			return head.Number.Uint64(), head.Time
@@ -128,22 +123,22 @@ func NewFilter(chain Blockchain) Filter {
 }
 
 // NewStaticFilter creates a filter at block zero.
-func NewStaticFilter(config *params.ChainConfig, genesis common.Hash) Filter {
+func NewStaticFilter(config *params.ChainConfig, genesis *types.Block) Filter {
 	head := func() (uint64, uint64) { return 0, 0 }
 	return newFilter(config, genesis, head)
 }
 
 // newFilter is the internal version of NewFilter, taking closures as its arguments
 // instead of a chain. The reason is to allow testing it without having to simulate
 // an entire blockchain.
-func newFilter(config *params.ChainConfig, genesis common.Hash, headfn func() (uint64, uint64)) Filter {
+func newFilter(config *params.ChainConfig, genesis *types.Block, headfn func() (uint64, uint64)) Filter {
 	// Calculate the all the valid fork hash and fork next combos
 	var (
-		forksByBlock, forksByTime = gatherForks(config)
+		forksByBlock, forksByTime = gatherForks(config, genesis.Time())
 		forks                     = append(append([]uint64{}, forksByBlock...), forksByTime...)
 		sums                      = make([][4]byte, len(forks)+1) // 0th is the genesis
 	)
-	hash := crc32.ChecksumIEEE(genesis[:])
+	hash := crc32.ChecksumIEEE(genesis.Hash().Bytes())
 	sums[0] = checksumToBytes(hash)
 	for i, fork := range forks {
 		hash = checksumUpdate(hash, fork)
@@ -244,7 +239,7 @@ func checksumToBytes(hash uint32) [4]byte {
 
 // gatherForks gathers all the known forks and creates two sorted lists out of
 // them, one for the block number based forks and the second for the timestamps.
-func gatherForks(config *params.ChainConfig) ([]uint64, []uint64) {
+func gatherForks(config *params.ChainConfig, genesis uint64) ([]uint64, []uint64) {
 	// Gather all the fork block numbers via reflection
 	kind := reflect.TypeOf(params.ChainConfig{})
 	conf := reflect.ValueOf(config).Elem()
@@ -294,7 +289,8 @@ func gatherForks(config *params.ChainConfig) ([]uint64, []uint64) {
 	if len(forksByBlock) > 0 && forksByBlock[0] == 0 {
 		forksByBlock = forksByBlock[1:]
 	}
-	if len(forksByTime) > 0 && forksByTime[0] == 0 {
+	// Skip any forks before genesis.
+	for len(forksByTime) > 0 && forksByTime[0] <= genesis {
 		forksByTime = forksByTime[1:]
 	}
 	return forksByBlock, forksByTime

core/forkid/forkid_test.go

@@ -357,7 +357,7 @@ func TestValidation(t *testing.T) {
 		//{params.MainnetChainConfig, 20999999, 1677999999, ID{Hash: checksumToBytes(0x71147644), Next: 1678000000}, ErrLocalIncompatibleOrStale},
 	}
 	for i, tt := range tests {
-		filter := newFilter(tt.config, params.MainnetGenesisHash, func() (uint64, uint64) { return tt.head, tt.time })
+		filter := newFilter(tt.config, core.DefaultGenesisBlock().ToBlock(), func() (uint64, uint64) { return tt.head, tt.time })
 		if err := filter(tt.id); err != tt.err {
 			t.Errorf("test %d: validation error mismatch: have %v, want %v", i, err, tt.err)
 		}