Modify rvgo for local context support

Author: pcw109550

rvgo/fast/evm.go

@@ -3,7 +3,8 @@ package fast
 import "github.com/ethereum/go-ethereum/crypto"
 
 var (
-	StepBytes4                      = crypto.Keccak256([]byte("step(bytes,bytes)"))[:4]
+	StepBytes4                      = crypto.Keccak256([]byte("step(bytes,bytes,bytes32)"))[:4]
 	CheatBytes4                     = crypto.Keccak256([]byte("cheat(uint256,bytes32,bytes32,uint256)"))[:4]
+	CheatLocalKeyBytes4             = crypto.Keccak256([]byte("cheatLocalKey(uint256,bytes32,bytes32,uint256,bytes32)"))[:4]
 	LoadKeccak256PreimagePartBytes4 = crypto.Keccak256([]byte("loadKeccak256PreimagePart(uint256,bytes)"))[:4]
 )

rvgo/fast/witness.go

@@ -5,9 +5,12 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/ethereum-optimism/optimism/op-preimage"
+	preimage "github.com/ethereum-optimism/optimism/op-preimage"
+	"github.com/ethereum/go-ethereum/common"
 )
 
+type LocalContext common.Hash
+
 type StepWitness struct {
 	// encoded state witness
 	State []byte
@@ -25,29 +28,35 @@ func uint64ToBytes32(v uint64) []byte {
 	return out[:]
 }
 
-func (wit *StepWitness) EncodeStepInput() []byte {
+func (wit *StepWitness) EncodeStepInput(localContext LocalContext) []byte {
 	abiStatePadding := (32 - (uint64(len(wit.State)) % 32)) % 32
+	abiProofPadding := (32 - (uint64(len(wit.MemProof)) % 32)) % 32
 
 	var input []byte
 	input = append(input, StepBytes4...)
-	input = append(input, uint64ToBytes32(32*2)...)                                           // state data offset in bytes
-	input = append(input, uint64ToBytes32(32*2+32+uint64(len(wit.State))+abiStatePadding)...) // proof data offset in bytes
-	// TODO pad state data to multiple of 32 bytes
-	// TODO also pad proof data
-
-	input = append(input, uint64ToBytes32(uint64(len(wit.State)))...) // state data length in bytes
+	// state data offset in bytes
+	input = append(input, uint64ToBytes32(32*3)...)
+	// proof data offset in bytes
+	input = append(input, uint64ToBytes32(32*3+32+uint64(len(wit.State))+abiStatePadding)...)
+	// local context in bytes
+	input = append(input, common.Hash(localContext).Bytes()...)
+	
+	// state data length in bytes
+	input = append(input, uint64ToBytes32(uint64(len(wit.State)))...)
 	input = append(input, wit.State[:]...)
 	input = append(input, make([]byte, abiStatePadding)...)
-	input = append(input, uint64ToBytes32(uint64(len(wit.MemProof)))...) // proof data length in bytes
+	// proof data length in bytes
+	input = append(input, uint64ToBytes32(uint64(len(wit.MemProof)))...)
 	input = append(input, wit.MemProof[:]...)
+	input = append(input, make([]byte, abiProofPadding)...)
 	return input
 }
 
 func (wit *StepWitness) HasPreimage() bool {
 	return wit.PreimageKey != ([32]byte{})
 }
 
-func (wit *StepWitness) EncodePreimageOracleInput() ([]byte, error) {
+func (wit *StepWitness) EncodePreimageOracleInput(localContext LocalContext) ([]byte, error) {
 	if wit.PreimageKey == ([32]byte{}) {
 		return nil, errors.New("cannot encode pre-image oracle input, witness has no pre-image to proof")
 	}
@@ -59,13 +68,14 @@ func (wit *StepWitness) EncodePreimageOracleInput() ([]byte, error) {
 		// In production usage there should be an on-chain contract that exposes this,
 		// rather than going through the global keccak256 oracle.
 		var input []byte
-		input = append(input, CheatBytes4...)
+		input = append(input, CheatLocalKeyBytes4...)
 		input = append(input, uint64ToBytes32(wit.PreimageOffset)...)
 		input = append(input, wit.PreimageKey[:]...)
 		var tmp [32]byte
 		copy(tmp[:], wit.PreimageValue[wit.PreimageOffset:])
 		input = append(input, tmp[:]...)
 		input = append(input, uint64ToBytes32(uint64(len(wit.PreimageValue))-8)...)
+		input = append(input, common.Hash(localContext).Bytes()...)
 		// Note: we can pad calldata to 32 byte multiple, but don't strictly have to
 		return input, nil
 	case preimage.Keccak256KeyType:

rvgo/slow/vm.go

@@ -3,6 +3,7 @@ package slow
 import (
 	"encoding/binary"
 	"fmt"
+
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 )
@@ -103,8 +104,8 @@ func Step(calldata []byte, po PreimageOracle) (stateHash common.Hash, outErr err
 
 	// TODO: validate abi offset values?
 
-	stateContentOffset := uint8(4 + 32 + 32 + 32)
-	if iszero(eq(b32asBEWord(calldataload(toU64(4+32*2))), shortToU256(stateSize))) {
+	stateContentOffset := uint8(4 + 32 + 32 + 32 + 32)
+	if iszero(eq(b32asBEWord(calldataload(toU64(4+32*3))), shortToU256(stateSize))) {
 		// user-provided state size must match expected state size
 		panic("invalid state size input")
 	}

rvgo/test/evm_test.go

@@ -149,13 +149,13 @@ func stepEVM(t *testing.T, env *vm.EVM, wit *fast.StepWitness, addrs *Addresses,
 	snap := env.StateDB.Snapshot()
 
 	if wit.HasPreimage() {
-		input, err := wit.EncodePreimageOracleInput()
+		input, err := wit.EncodePreimageOracleInput(fast.LocalContext{})
 		require.NoError(t, err)
 		ret, leftOverGas, err := env.Call(vm.AccountRef(addrs.Sender), addrs.Oracle, input, startingGas, big.NewInt(0))
 		require.NoError(t, err, "evm must not fail (ret: %x, gas: %d)", ret, startingGas-leftOverGas)
 	}
 
-	input := wit.EncodeStepInput()
+	input := wit.EncodeStepInput(fast.LocalContext{})
 
 	ret, leftOverGas, err := env.Call(vm.AccountRef(addrs.Sender), addrs.RISCV, input, startingGas, big.NewInt(0))
 	require.NoError(t, err, "evm must not fail (ret: %x), at step %d", ret, step)

rvgo/test/vm_go_test.go

@@ -108,7 +108,7 @@ func fullTest(t *testing.T, vmState *fast.VMState, po *testOracle, symbols fast.
 			require.NoError(t, err)
 
 			if runSlow {
-				slowPostHash, err := slow.Step(wit.EncodeStepInput(), po)
+				slowPostHash, err := slow.Step(wit.EncodeStepInput(fast.LocalContext{}), po)
 				require.NoErrorf(t, err, "slow VM err at step %d, PC %08x: %v", i, vmState.PC, err)
 				require.Equal(t, fastStateHash, slowPostHash, "fast post-state must match slow post-state")
 			}

rvgo/test/vm_test.go

@@ -75,7 +75,7 @@ func runSlowTestSuite(t *testing.T, path string) {
 		require.NoError(t, err)
 
 		// Now run the same in slow mode
-		input := wit.EncodeStepInput()
+		input := wit.EncodeStepInput(fast.LocalContext{})
 		post, err := slow.Step(input, nil)
 		require.NoErrorf(t, err, "slow VM err at step %d, PC %08x: %v", i, vmState.PC, err)