params: update

params/chainparam.go

@@ -1,6 +1,7 @@
 package params
 
 import (
+	"fmt"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -10,9 +11,46 @@ import (
 // ChainID
 type ChainID big.Int
 
+func NewChainID(input string) *ChainID {
+	b, ok := new(big.Int).SetString(input, 0)
+	if !ok {
+		panic("invalid chainID: " + input)
+	}
+	return (*ChainID)(b)
+}
+
+func (v *ChainID) MarshalText() ([]byte, error) {
+	return (*big.Int)(v).MarshalText()
+}
+
+func (v *ChainID) UnmarshalText(input []byte) error {
+	return (*big.Int)(v).UnmarshalText(input)
+}
+
+func (v *ChainID) BigInt() *big.Int {
+	return (*big.Int)(v)
+}
+
+func (v *ChainID) Validate(cfg *Config2) error {
+	b := (*big.Int)(v)
+	if b.Sign() <= 0 {
+		return fmt.Errorf("invalid chainID value %v", b)
+	}
+
+	return nil
+}
+
 // TerminalTotalDifficulty (TTD) is the total difficulty value where
 type TerminalTotalDifficulty big.Int
 
+func NewTerminalTotalDifficulty(input string) *TerminalTotalDifficulty {
+	b, ok := new(big.Int).SetString(input, 0)
+	if !ok {
+		panic("invalid terminal total difficulty: " + input)
+	}
+	return (*TerminalTotalDifficulty)(b)
+}
+
 func (v *TerminalTotalDifficulty) MarshalText() ([]byte, error) {
 	return (*big.Int)(v).MarshalText()
 }
@@ -21,18 +59,49 @@ func (v *TerminalTotalDifficulty) UnmarshalText(input []byte) error {
 	return (*big.Int)(v).UnmarshalText(input)
 }
 
+func (v *TerminalTotalDifficulty) Validate(cfg *Config2) error {
+	return nil
+}
+
 // DepositContractAddress configures the location of the deposit contract.
 type DepositContractAddress common.Address
 
+func (v DepositContractAddress) Validate(cfg *Config2) error {
+	return nil
+}
+
 // This configures the EIP-4844 parameters across forks.
 // There must be an entry for each fork
 type BlobSchedule map[forks.Fork]BlobConfig
 
+// Validate checks that all forks with blobs explicitly define the blob schedule configuration.
+func (v BlobSchedule) Validate(cfg *Config2) error {
+	for _, f := range forks.CanonOrder {
+		if f.HasBlobs() {
+			schedule := Get[BlobSchedule](cfg)
+			bcfg, defined := schedule[f]
+			if cfg.Scheduled(f) && !defined {
+				return fmt.Errorf("invalid chain configuration: missing entry for fork %q in blobSchedule", f)
+			}
+			if defined {
+				if err := bcfg.validate(); err != nil {
+					return fmt.Errorf("invalid chain configuration in blobSchedule for fork %q: %v", f, err)
+				}
+			}
+		}
+	}
+	return nil
+}
+
 // DAOForkSupport is the chain parameter that configures the DAO fork.
 // true=supports or false=opposes the fork.
 // The default value is true.
 type DAOForkSupport bool
 
+func (v DAOForkSupport) Validate(cfg *Config2) error {
+	return nil
+}
+
 func init() {
 	Define(Parameter[*ChainID]{
 		Name:     "chainId",

params/config2.go

@@ -43,6 +43,7 @@ func NewConfig2(activations Activations, param ...ParameterType) *Config2 {
 		activation: maps.Clone(activations),
 		param:      make(map[reflect.Type]ParameterType, len(param)),
 	}
+	cfg.activation[forks.Frontier] = 0
 	for _, pv := range param {
 		info, ok := findParam(pv)
 		if !ok {
@@ -62,6 +63,16 @@ func (cfg *Config2) Active(f forks.Fork, block, timestamp uint64) bool {
 	return ok && timestamp >= activation
 }
 
+// ActiveAtBlock reports whether the given fork is active for a block number/time.
+func (cfg *Config2) ActiveAtBlock(f forks.Fork, block *big.Int) bool {
+	if !f.BlockBased() {
+		panic(fmt.Sprintf("fork %v has time-based scheduling", f))
+	}
+	activation, ok := cfg.activation[f]
+	return ok && block.Uint64() >= activation
+}
+
+// Activation returns the activation block/number of a fork.
 func (cfg *Config2) Activation(f forks.Fork) (uint64, bool) {
 	a, ok := cfg.activation[f]
 	return a, ok
@@ -80,11 +91,6 @@ func (cfg *Config2) SetActivations(forks Activations) *Config2 {
 	return &Config2{activation: newA, param: cfg.param}
 }
 
-// SetParam returns a new configuration with parameters modified.
-func (cfg *Config2) SetParam(p ParameterType) *Config2 {
-	return &Config2{activation: cfg.activation}
-}
-
 // LatestFork returns the latest time-based fork that would be active for the given time.
 func (cfg *Config2) LatestFork(time uint64) forks.Fork {
 	londonBlock := cfg.activation[forks.London]
@@ -189,7 +195,7 @@ func (cfg *Config2) decodeParameter(key string, dec *json.Decoder) error {
 	if err := dec.Decode(v); err != nil {
 		return err
 	}
-	cfg.param[info.rtype] = v
+	cfg.param[info.rtype] = v.(ParameterType)
 	return nil
 }
 
@@ -198,6 +204,7 @@ func (cfg *Config2) decodeParameter(key string, dec *json.Decoder) error {
 func (cfg *Config2) Validate() error {
 	sanityCheckCanonOrder()
 
+	// Check forks.
 	lastFork := forks.CanonOrder[0]
 	for _, f := range forks.CanonOrder[1:] {
 		act := "timestamp"
@@ -225,21 +232,22 @@ func (cfg *Config2) Validate() error {
 		if !f.Optional() || cfg.Scheduled(f) {
 			lastFork = f
 		}
+	}
 
-		// Check that all forks with blobs explicitly define the blob schedule configuration.
+	// Check parameters.
-		if f.HasBlobs() {
+	for rtype, info := range paramRegistry {
-			schedule := Get[BlobSchedule](cfg)
+		v, isSet := cfg.param[rtype]
-			bcfg, defined := schedule[f]
+		if !isSet {
-			if cfg.Scheduled(f) && !defined {
+			if !info.optional {
-				return fmt.Errorf("invalid chain configuration: missing entry for fork %q in blobSchedule", f)
+				return fmt.Errorf("required chain parameter %s is not set", info.name)
-			}
-			if defined {
-				if err := bcfg.validate(); err != nil {
-					return fmt.Errorf("invalid chain configuration in blobSchedule for fork %q: %v", f, err)
-				}
 			}
+			v = info.defaultVal
+		}
+		if err := v.Validate(cfg); err != nil {
+			return fmt.Errorf("invalid %s: %w", info.name, err)
 		}
 	}
+
 	return nil
 }
 
@@ -286,16 +294,17 @@ func (cfg *Config2) checkCompatible(newcfg *Config2, num uint64, time uint64) *C
 			}
 			return newTimestampCompatError2("%v fork timestamp", f, cfg, newcfg)
 		}
-		// Specialty checks:
-		if cfg.Active(forks.DAO, num, time) && Get[DAOForkSupport](cfg) != Get[DAOForkSupport](newcfg) {
-			return newBlockCompatError2("DAO fork support flag", f, cfg, newcfg)
-		}
-		chainID := (*big.Int)(Get[*ChainID](cfg))
-		newChainID := (*big.Int)(Get[*ChainID](newcfg))
-		if cfg.Active(forks.TangerineWhistle, num, time) && !configBlockEqual(chainID, newChainID) {
-			return newBlockCompatError2("EIP158 chain ID", f, cfg, newcfg)
-		}
 	}
+
+	if cfg.Active(forks.DAO, num, time) && Get[DAOForkSupport](cfg) != Get[DAOForkSupport](newcfg) {
+		return newBlockCompatError2("DAO fork support flag", forks.DAO, cfg, newcfg)
+	}
+	chainID := (*big.Int)(Get[*ChainID](cfg))
+	newChainID := (*big.Int)(Get[*ChainID](newcfg))
+	if cfg.Active(forks.TangerineWhistle, num, time) && !configBlockEqual(chainID, newChainID) {
+		return newBlockCompatError2("EIP158 chain ID", forks.TangerineWhistle, cfg, newcfg)
+	}
+
 	return nil
 }
 

params/config2_presets.go

@@ -1,115 +0,0 @@
-// Copyright 2025 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 params
-
-import (
-	"math"
-	"math/big"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/params/forks"
-)
-
-var (
-	MainnetConfig2            *Config2
-	AllEthashProtocolChanges2 *Config2
-	MergedTestChainConfig2    *Config2
-)
-
-func init() {
-	MainnetConfig2 = NewConfig2(
-		Activations{
-			forks.Homestead:        1_150_000,
-			forks.DAO:              1_920_000,
-			forks.TangerineWhistle: 2_463_000,
-			forks.SpuriousDragon:   2_675_000,
-			forks.Byzantium:        4_370_000,
-			forks.Constantinople:   7_280_000,
-			forks.Petersburg:       7_280_000,
-			forks.Istanbul:         9_069_000,
-			forks.MuirGlacier:      9_200_000,
-			forks.Berlin:           12_244_000,
-			forks.London:           12_965_000,
-			forks.ArrowGlacier:     13_773_000,
-			forks.GrayGlacier:      15_050_000,
-			// time-based forks
-			forks.Shanghai: 1681338455,
-			forks.Cancun:   1710338135,
-			forks.Prague:   1746612311,
-		},
-		(*ChainID)(big.NewInt(1)),
-		(*TerminalTotalDifficulty)(MainnetTerminalTotalDifficulty),
-		DepositContractAddress(common.HexToAddress("0x00000000219ab540356cbb839cbe05303d7705fa")),
-		DAOForkSupport(true),
-		BlobSchedule{
-			forks.Cancun: *DefaultCancunBlobConfig,
-			forks.Prague: *DefaultPragueBlobConfig,
-		},
-	)
-
-	// AllEthashProtocolChanges2 contains every protocol change (EIPs) introduced
-	// and accepted by the Ethereum core developers into the Ethash consensus.
-	AllEthashProtocolChanges2 = NewConfig2(
-		Activations{
-			forks.Homestead:        0,
-			forks.TangerineWhistle: 0,
-			forks.SpuriousDragon:   0,
-			forks.Byzantium:        0,
-			forks.Constantinople:   0,
-			forks.Petersburg:       0,
-			forks.Istanbul:         0,
-			forks.MuirGlacier:      0,
-			forks.Berlin:           0,
-			forks.London:           0,
-			forks.ArrowGlacier:     0,
-			forks.GrayGlacier:      0,
-		},
-		(*ChainID)(big.NewInt(1337)),
-		(*TerminalTotalDifficulty)(big.NewInt(math.MaxInt64)),
-	)
-
-	// MergedTestChainConfig2 contains every protocol change (EIPs) introduced
-	// and accepted by the Ethereum core developers for testing purposes.
-	MergedTestChainConfig2 = NewConfig2(
-		Activations{
-			forks.Homestead:        0,
-			forks.TangerineWhistle: 0,
-			forks.SpuriousDragon:   0,
-			forks.Byzantium:        0,
-			forks.Constantinople:   0,
-			forks.Petersburg:       0,
-			forks.Istanbul:         0,
-			forks.MuirGlacier:      0,
-			forks.Berlin:           0,
-			forks.London:           0,
-			forks.ArrowGlacier:     0,
-			forks.GrayGlacier:      0,
-			forks.Paris:            0,
-			forks.Shanghai:         0,
-			forks.Cancun:           0,
-			forks.Prague:           0,
-			forks.Osaka:            0,
-		},
-		(*ChainID)(big.NewInt(1)),
-		(*TerminalTotalDifficulty)(big.NewInt(0)),
-		BlobSchedule{
-			forks.Cancun: *DefaultCancunBlobConfig,
-			forks.Prague: *DefaultPragueBlobConfig,
-			forks.Osaka:  *DefaultOsakaBlobConfig,
-		},
-	)
-}

params/presets/presets.go

@@ -0,0 +1,134 @@
+// Copyright 2025 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 presets
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/params"
+	"github.com/ethereum/go-ethereum/params/forks"
+)
+
+var Mainnet = params.NewConfig2(
+	params.Activations{
+		forks.Homestead:        1_150_000,
+		forks.DAO:              1_920_000,
+		forks.TangerineWhistle: 2_463_000,
+		forks.SpuriousDragon:   2_675_000,
+		forks.Byzantium:        4_370_000,
+		forks.Constantinople:   7_280_000,
+		forks.Petersburg:       7_280_000,
+		forks.Istanbul:         9_069_000,
+		forks.MuirGlacier:      9_200_000,
+		forks.Berlin:           12_244_000,
+		forks.London:           12_965_000,
+		forks.ArrowGlacier:     13_773_000,
+		forks.GrayGlacier:      15_050_000,
+		forks.Paris:            15_537_393,
+		// time-based forks
+		forks.Shanghai: 1681338455,
+		forks.Cancun:   1710338135,
+		forks.Prague:   1746612311,
+	},
+	params.NewChainID("1"),
+	params.NewTerminalTotalDifficulty("58_750_000_000_000_000_000_000"),
+	params.DepositContractAddress(common.HexToAddress("0x00000000219ab540356cbb839cbe05303d7705fa")),
+	params.DAOForkSupport(true),
+	params.BlobSchedule{
+		forks.Cancun: *params.DefaultCancunBlobConfig,
+		forks.Prague: *params.DefaultPragueBlobConfig,
+	},
+)
+
+// SepoliaChainConfig contains the chain parameters to run a node on the Sepolia test network.
+var Sepolia = params.NewConfig2(
+	params.Activations{
+		forks.Homestead:        0,
+		forks.TangerineWhistle: 0,
+		forks.SpuriousDragon:   0,
+		forks.Byzantium:        0,
+		forks.Constantinople:   0,
+		forks.Petersburg:       0,
+		forks.Istanbul:         0,
+		forks.MuirGlacier:      0,
+		forks.Berlin:           0,
+		forks.London:           0,
+		forks.Paris:            1735371,
+		// time-based forks
+		forks.Shanghai: 1677557088,
+		forks.Cancun:   1706655072,
+		forks.Prague:   1741159776,
+	},
+	params.NewChainID("11155111"),
+	params.NewTerminalTotalDifficulty("17_000_000_000_000_000"),
+	params.DepositContractAddress(common.HexToAddress("0x7f02c3e3c98b133055b8b348b2ac625669ed295d")),
+	params.BlobSchedule{
+		forks.Cancun: *params.DefaultCancunBlobConfig,
+		forks.Prague: *params.DefaultPragueBlobConfig,
+	},
+)
+
+// AllEthashProtocolChanges2 contains every protocol change (EIPs) introduced
+// and accepted by the Ethereum core developers into the Ethash consensus.
+var AllEthashProtocolChanges = params.NewConfig2(
+	params.Activations{
+		forks.Homestead:        0,
+		forks.TangerineWhistle: 0,
+		forks.SpuriousDragon:   0,
+		forks.Byzantium:        0,
+		forks.Constantinople:   0,
+		forks.Petersburg:       0,
+		forks.Istanbul:         0,
+		forks.MuirGlacier:      0,
+		forks.Berlin:           0,
+		forks.London:           0,
+		forks.ArrowGlacier:     0,
+		forks.GrayGlacier:      0,
+	},
+	params.NewChainID("1337"),
+	params.NewTerminalTotalDifficulty("0xffffffffffffff"),
+)
+
+// MergedTestChainConfig2 contains every protocol change (EIPs) introduced
+// and accepted by the Ethereum core developers for testing purposes.
+var MergedTestChainConfig = params.NewConfig2(
+	params.Activations{
+		forks.Homestead:        0,
+		forks.TangerineWhistle: 0,
+		forks.SpuriousDragon:   0,
+		forks.Byzantium:        0,
+		forks.Constantinople:   0,
+		forks.Petersburg:       0,
+		forks.Istanbul:         0,
+		forks.MuirGlacier:      0,
+		forks.Berlin:           0,
+		forks.London:           0,
+		forks.ArrowGlacier:     0,
+		forks.GrayGlacier:      0,
+		forks.Paris:            0,
+		forks.Shanghai:         0,
+		forks.Cancun:           0,
+		forks.Prague:           0,
+		forks.Osaka:            0,
+	},
+	params.NewChainID("1"),
+	params.NewTerminalTotalDifficulty("0"),
+	params.BlobSchedule{
+		forks.Cancun: *params.DefaultCancunBlobConfig,
+		forks.Prague: *params.DefaultPragueBlobConfig,
+		forks.Osaka:  *params.DefaultOsakaBlobConfig,
+	},
+)

params/presets/presets_test.go

@@ -0,0 +1,12 @@
+package presets
+
+import "testing"
+
+func TestPresetsValidate(t *testing.T) {
+	if err := Mainnet.Validate(); err != nil {
+		t.Fatal("mainnet is invalid:", err)
+	}
+	if err := Sepolia.Validate(); err != nil {
+		t.Fatal("sepolia is invalid:", err)
+	}
+}

params/registry.go

@@ -21,13 +21,15 @@ import (
 	"reflect"
 )
 
-type ParameterType any
+type ParameterType interface{
+	Validate(*Config2) error
+}
 
 type paramInfo struct {
 	rtype      reflect.Type
 	name       string
 	optional   bool
-	defaultVal any
+	defaultVal ParameterType
 }
 
 var (
@@ -35,12 +37,6 @@ var (
 	paramRegistryByName = map[string]*paramInfo{}
 )
 
-type Parameter[T ParameterType] struct {
-	Name     string
-	Optional bool
-	Default  T
-}
-
 // Get retrieves the value of a chain parameter.
 func Get[T ParameterType](cfg *Config2) T {
 	for _, p := range cfg.param {
@@ -57,6 +53,14 @@ func Get[T ParameterType](cfg *Config2) T {
 	return info.defaultVal.(T)
 }
 
+// Parameter is the definition of a chain parameter.
+type Parameter[T ParameterType] struct {
+	Name     string
+	Optional bool
+	Default  T
+}
+
+// Define creates a chain parameter in the registry.
 func Define[T ParameterType](def Parameter[T]) {
 	var z T
 	info, defined := paramRegistryByName[def.Name]