core/evm: RANDOM opcode (EIP-4399) (#24141)

* core: implement eip-4399 random opcode

* core: make vmconfig threadsafe

* core: miner: pass vmConfig by value not reference

* all: enable 4399 by Rules

* core: remove diff (f)

* tests: set proper difficulty (f)

* smaller diff (f)

* eth/catalyst: nit

* core: make RANDOM a pointer which is only set post-merge

* cmd/evm/internal/t8ntool: fix t8n tracing of 4399

* tests: set difficulty

* cmd/evm/internal/t8ntool: check that baserules are london before applying the merge chainrules

core/vm/evm.go

@@ -75,6 +75,7 @@ type BlockContext struct {
 	Time        *big.Int       // Provides information for TIME
 	Difficulty  *big.Int       // Provides information for DIFFICULTY
 	BaseFee     *big.Int       // Provides information for BASEFEE
+	Random      *common.Hash   // Provides information for RANDOM
 }
 
 // TxContext provides the EVM with information about a transaction.
@@ -131,7 +132,7 @@ func NewEVM(blockCtx BlockContext, txCtx TxContext, statedb StateDB, chainConfig
 		StateDB:     statedb,
 		Config:      config,
 		chainConfig: chainConfig,
-		chainRules:  chainConfig.Rules(blockCtx.BlockNumber),
+		chainRules:  chainConfig.Rules(blockCtx.BlockNumber, blockCtx.Random != nil),
 	}
 	evm.interpreter = NewEVMInterpreter(evm, config)
 	return evm

core/vm/instructions.go

@@ -477,6 +477,12 @@ func opDifficulty(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext)
 	return nil, nil
 }
 
+func opRandom(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) ([]byte, error) {
+	v := new(uint256.Int).SetBytes((interpreter.evm.Context.Random.Bytes()))
+	scope.Stack.push(v)
+	return nil, nil
+}
+
 func opGasLimit(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) ([]byte, error) {
 	scope.Stack.push(new(uint256.Int).SetUint64(interpreter.evm.Context.GasLimit))
 	return nil, nil

core/vm/instructions_test.go

@@ -21,6 +21,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"math/big"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -654,3 +655,36 @@ func TestCreate2Addreses(t *testing.T) {
 		}
 	}
 }
+
+func TestRandom(t *testing.T) {
+	type testcase struct {
+		name   string
+		random common.Hash
+	}
+
+	for _, tt := range []testcase{
+		{name: "empty hash", random: common.Hash{}},
+		{name: "1", random: common.Hash{0}},
+		{name: "emptyCodeHash", random: emptyCodeHash},
+		{name: "hash(0x010203)", random: crypto.Keccak256Hash([]byte{0x01, 0x02, 0x03})},
+	} {
+		var (
+			env            = NewEVM(BlockContext{Random: &tt.random}, TxContext{}, nil, params.TestChainConfig, Config{})
+			stack          = newstack()
+			pc             = uint64(0)
+			evmInterpreter = env.interpreter
+		)
+		opRandom(&pc, evmInterpreter, &ScopeContext{nil, stack, nil})
+		if len(stack.data) != 1 {
+			t.Errorf("Expected one item on stack after %v, got %d: ", tt.name, len(stack.data))
+		}
+		actual := stack.pop()
+		expected, overflow := uint256.FromBig(new(big.Int).SetBytes(tt.random.Bytes()))
+		if overflow {
+			t.Errorf("Testcase %v: invalid overflow", tt.name)
+		}
+		if actual.Cmp(expected) != 0 {
+			t.Errorf("Testcase %v: expected  %x, got %x", tt.name, expected, actual)
+		}
+	}
+}

core/vm/interpreter.go

@@ -69,6 +69,8 @@ func NewEVMInterpreter(evm *EVM, cfg Config) *EVMInterpreter {
 	// If jump table was not initialised we set the default one.
 	if cfg.JumpTable == nil {
 		switch {
+		case evm.chainRules.IsMerge:
+			cfg.JumpTable = &mergeInstructionSet
 		case evm.chainRules.IsLondon:
 			cfg.JumpTable = &londonInstructionSet
 		case evm.chainRules.IsBerlin:

core/vm/jump_table.go

@@ -54,6 +54,7 @@ var (
 	istanbulInstructionSet         = newIstanbulInstructionSet()
 	berlinInstructionSet           = newBerlinInstructionSet()
 	londonInstructionSet           = newLondonInstructionSet()
+	mergeInstructionSet            = newMergeInstructionSet()
 )
 
 // JumpTable contains the EVM opcodes supported at a given fork.
@@ -77,6 +78,17 @@ func validate(jt JumpTable) JumpTable {
 	return jt
 }
 
+func newMergeInstructionSet() JumpTable {
+	instructionSet := newLondonInstructionSet()
+	instructionSet[RANDOM] = &operation{
+		execute:     opRandom,
+		constantGas: GasQuickStep,
+		minStack:    minStack(0, 1),
+		maxStack:    maxStack(0, 1),
+	}
+	return validate(instructionSet)
+}
+
 // newLondonInstructionSet returns the frontier, homestead, byzantium,
 // contantinople, istanbul, petersburg, berlin and london instructions.
 func newLondonInstructionSet() JumpTable {

core/vm/opcodes.go

@@ -95,6 +95,7 @@ const (
 	TIMESTAMP   OpCode = 0x42
 	NUMBER      OpCode = 0x43
 	DIFFICULTY  OpCode = 0x44
+	RANDOM      OpCode = 0x44 // Same as DIFFICULTY
 	GASLIMIT    OpCode = 0x45
 	CHAINID     OpCode = 0x46
 	SELFBALANCE OpCode = 0x47
@@ -275,7 +276,7 @@ var opCodeToString = map[OpCode]string{
 	COINBASE:    "COINBASE",
 	TIMESTAMP:   "TIMESTAMP",
 	NUMBER:      "NUMBER",
-	DIFFICULTY:  "DIFFICULTY",
+	DIFFICULTY:  "DIFFICULTY", // TODO (MariusVanDerWijden) rename to RANDOM post merge
 	GASLIMIT:    "GASLIMIT",
 	CHAINID:     "CHAINID",
 	SELFBALANCE: "SELFBALANCE",

core/vm/runtime/runtime.go

@@ -118,7 +118,7 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 		vmenv   = NewEnv(cfg)
 		sender  = vm.AccountRef(cfg.Origin)
 	)
-	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
+	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber, vmenv.Context.Random != nil); rules.IsBerlin {
 		cfg.State.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules), nil)
 	}
 	cfg.State.CreateAccount(address)
@@ -150,7 +150,7 @@ func Create(input []byte, cfg *Config) ([]byte, common.Address, uint64, error) {
 		vmenv  = NewEnv(cfg)
 		sender = vm.AccountRef(cfg.Origin)
 	)
-	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
+	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber, vmenv.Context.Random != nil); rules.IsBerlin {
 		cfg.State.PrepareAccessList(cfg.Origin, nil, vm.ActivePrecompiles(rules), nil)
 	}
 	// Call the code with the given configuration.
@@ -176,7 +176,7 @@ func Call(address common.Address, input []byte, cfg *Config) ([]byte, uint64, er
 	sender := cfg.State.GetOrNewStateObject(cfg.Origin)
 	statedb := cfg.State
 
-	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber); rules.IsBerlin {
+	if rules := cfg.ChainConfig.Rules(vmenv.Context.BlockNumber, vmenv.Context.Random != nil); rules.IsBerlin {
 		statedb.PrepareAccessList(cfg.Origin, &address, vm.ActivePrecompiles(rules), nil)
 	}
 	// Call the code with the given configuration.