config: support extra precompiles

Author: tsahee

core/state_transition.go

@@ -308,7 +308,7 @@ func (st *StateTransition) TransitionDb() (*ExecutionResult, error) {
 
 	// Set up the initial access list.
 	if rules := st.evm.ChainConfig().Rules(st.evm.Context.BlockNumber); rules.IsBerlin {
-		st.state.PrepareAccessList(msg.From(), msg.To(), vm.ActivePrecompiles(rules), msg.AccessList())
+		st.state.PrepareAccessList(msg.From(), msg.To(), vm.ActivePrecompiles(rules, st.evm.ChainConfig()), msg.AccessList())
 	}
 	var (
 		ret   []byte

core/vm/contracts.go

@@ -128,8 +128,7 @@ func init() {
 	}
 }
 
-// ActivePrecompiles returns the precompiles enabled with the current configuration.
-func ActivePrecompiles(rules params.Rules) []common.Address {
+func ethereumPrecompiles(rules params.Rules) []common.Address {
 	switch {
 	case rules.IsBerlin:
 		return PrecompiledAddressesBerlin
@@ -142,6 +141,15 @@ func ActivePrecompiles(rules params.Rules) []common.Address {
 	}
 }
 
+// ActivePrecompiles returns the precompiles enabled with the current configuration.
+func ActivePrecompiles(rules params.Rules, chainConfig *params.ChainConfig) []common.Address {
+	res := ethereumPrecompiles(rules)
+	for _, precompile := range chainConfig.ExtraPrecompiles {
+		res = append(res, common.BigToAddress(&precompile))
+	}
+	return res
+}
+
 // RunPrecompiledContract runs and evaluates the output of a precompiled contract.
 // It returns
 // - the returned bytes,

core/vm/evm.go

@@ -42,6 +42,11 @@ type (
 )
 
 func (evm *EVM) precompile(addr common.Address) (PrecompiledContract, bool) {
+	p0, ok0 := evm.Config.ExtraPrecompiles[addr]
+	if ok0 {
+		return p0, ok0
+	}
+
 	var precompiles map[common.Address]PrecompiledContract
 	switch {
 	case evm.chainRules.IsBerlin:

core/vm/interpreter.go

@@ -36,6 +36,8 @@ type Config struct {
 	JumpTable [256]*operation // EVM instruction table, automatically populated if unset
 
 	ExtraEips []int // Additional EIPS that are to be enabled
+
+	ExtraPrecompiles map[common.Address]PrecompiledContract
 }
 
 // ScopeContext contains the things that are per-call, such as stack and memory,

core/vm/runtime/runtime.go

@@ -119,7 +119,7 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 		sender  = vm.AccountRef(cfg.Origin)
 	)
 	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
-		cfg.State.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules), nil)
+		cfg.State.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules, cfg.ChainConfig), nil)
 	}
 	cfg.State.CreateAccount(address)
 	// set the receiver's (the executing contract) code for execution.
@@ -151,7 +151,7 @@ func Create(input []byte, cfg *Config) ([]byte, common.Address, uint64, error) {
 		sender = vm.AccountRef(cfg.Origin)
 	)
 	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
-		cfg.State.PrepareAccessList(cfg.Origin, nil, vm.ActivePrecompiles(rules), nil)
+		cfg.State.PrepareAccessList(cfg.Origin, nil, vm.ActivePrecompiles(rules, cfg.ChainConfig), nil)
 	}
 	// Call the code with the given configuration.
 	code, address, leftOverGas, err := vmenv.Create(
@@ -177,7 +177,7 @@ func Call(address common.Address, input []byte, cfg *Config) ([]byte, uint64, er
 	statedb := cfg.State
 
 	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
-		statedb.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules), nil)
+		statedb.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules, cfg.ChainConfig), nil)
 	}
 	// Call the code with the given configuration.
 	ret, leftOverGas, err := vmenv.Call(

eth/tracers/tracer.go

@@ -687,7 +687,7 @@ func (jst *Tracer) CaptureStart(env *vm.EVM, from common.Address, to common.Addr
 	jst.dbWrapper.db = env.StateDB
 	// Update list of precompiles based on current block
 	rules := env.ChainConfig().Rules(env.Context.BlockNumber)
-	jst.activePrecompiles = vm.ActivePrecompiles(rules)
+	jst.activePrecompiles = vm.ActivePrecompiles(rules, env.ChainConfig())
 
 	// Compute intrinsic gas
 	isHomestead := env.ChainConfig().IsHomestead(env.Context.BlockNumber)

internal/ethapi/api.go

@@ -1429,7 +1429,7 @@ func AccessList(ctx context.Context, b Backend, blockNrOrHash rpc.BlockNumberOrH
 		to = crypto.CreateAddress(args.from(), uint64(*args.Nonce))
 	}
 	// Retrieve the precompiles since they don't need to be added to the access list
-	precompiles := vm.ActivePrecompiles(b.ChainConfig().Rules(header.Number))
+	precompiles := vm.ActivePrecompiles(b.ChainConfig().Rules(header.Number), b.ChainConfig())
 
 	// Create an initial tracer
 	prevTracer := vm.NewAccessListTracer(nil, args.from(), to, precompiles)

params/config.go

@@ -225,16 +225,16 @@ var (
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil}
+	AllEthashProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil, nil}
 
 	// AllCliqueProtocolChanges contains every protocol change (EIPs) introduced
 	// and accepted by the Ethereum core developers into the Clique consensus.
 	//
 	// This configuration is intentionally not using keyed fields to force anyone
 	// adding flags to the config to also have to set these fields.
-	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}}
+	AllCliqueProtocolChanges = &ChainConfig{big.NewInt(1337), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, nil, &CliqueConfig{Period: 0, Epoch: 30000}, nil}
 
-	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil}
+	TestChainConfig = &ChainConfig{big.NewInt(1), big.NewInt(0), nil, false, big.NewInt(0), common.Hash{}, big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), big.NewInt(0), nil, new(EthashConfig), nil, nil}
 	TestRules       = TestChainConfig.Rules(new(big.Int))
 )
 
@@ -319,6 +319,8 @@ type ChainConfig struct {
 	// Various consensus engines
 	Ethash *EthashConfig `json:"ethash,omitempty"`
 	Clique *CliqueConfig `json:"clique,omitempty"`
+
+	ExtraPrecompiles []big.Int `json:"extraPrecompiles,omitempty"`
 }
 
 // EthashConfig is the consensus engine configs for proof-of-work based sealing.