From 973539b022f47a57a9342d36e6a39fd3f04569d2 Mon Sep 17 00:00:00 2001
From: Petar Ivanov <29689712+dartdart26@users.noreply.github.com>
Date: Thu, 2 Nov 2023 18:11:27 +0200
Subject: [PATCH] feat: add implementation of OpSelfdestruct

---
 fhevm/evm.go          |  6 +++---
 fhevm/instructions.go | 18 +++++++++++++++---
 fhevm/interface.go    |  4 ++++
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/fhevm/evm.go b/fhevm/evm.go
index db090e6..e986d12 100644
--- a/fhevm/evm.go
+++ b/fhevm/evm.go
@@ -9,7 +9,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/holiman/uint256"
-	ps "github.com/zama-ai/fhevm-go/crypto"
+	fhevm_crypto "github.com/zama-ai/fhevm-go/crypto"
 )
 
 // A Logger interface for the EVM.
@@ -170,7 +170,7 @@ func padArrayTo32Multiple(input []byte) []byte {
 
 func Create(evm EVMEnvironment, caller common.Address, code []byte, gas uint64, value *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
 	contractAddr = crypto.CreateAddress(caller, evm.GetNonce(caller))
-	protectedStorageAddr := ps.CreateProtectedStorageContractAddress(contractAddr)
+	protectedStorageAddr := fhevm_crypto.CreateProtectedStorageContractAddress(contractAddr)
 	_, _, leftOverGas, err = evm.CreateContract(caller, nil, gas, big.NewInt(0), protectedStorageAddr)
 	if err != nil {
 		ret = nil
@@ -184,7 +184,7 @@ func Create(evm EVMEnvironment, caller common.Address, code []byte, gas uint64,
 func Create2(evm EVMEnvironment, caller common.Address, code []byte, gas uint64, endowment *big.Int, salt *uint256.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
 	codeHash := crypto.Keccak256Hash(code)
 	contractAddr = crypto.CreateAddress2(caller, salt.Bytes32(), codeHash.Bytes())
-	protectedStorageAddr := ps.CreateProtectedStorageContractAddress(contractAddr)
+	protectedStorageAddr := fhevm_crypto.CreateProtectedStorageContractAddress(contractAddr)
 	_, _, leftOverGas, err = evm.CreateContract2(caller, nil, common.Hash{}, gas, big.NewInt(0), protectedStorageAddr)
 	if err != nil {
 		ret = nil
diff --git a/fhevm/instructions.go b/fhevm/instructions.go
index 87237bd..3f479e3 100644
--- a/fhevm/instructions.go
+++ b/fhevm/instructions.go
@@ -4,12 +4,13 @@ import (
 	"bytes"
 	"encoding/hex"
 	"errors"
+	"math/big"
 	"strings"
 
 	"github.com/ethereum/go-ethereum/common"
 	crypto "github.com/ethereum/go-ethereum/crypto"
 	"github.com/holiman/uint256"
-	ps "github.com/zama-ai/fhevm-go/crypto"
+	fhevm_crypto "github.com/zama-ai/fhevm-go/crypto"
 )
 
 var zero = uint256.NewInt(0).Bytes32()
@@ -152,7 +153,7 @@ func verifyIfCiphertextHandle(handle common.Hash, env EVMEnvironment, contractAd
 	}
 
 	metadataKey := crypto.Keccak256Hash(handle.Bytes())
-	protectedStorage := ps.CreateProtectedStorageContractAddress(contractAddress)
+	protectedStorage := fhevm_crypto.CreateProtectedStorageContractAddress(contractAddress)
 	metadataInt := newInt(env.GetState(protectedStorage, metadataKey).Bytes())
 	if !metadataInt.IsZero() {
 		metadata := newCiphertextMetadata(metadataInt.Bytes32())
@@ -274,7 +275,7 @@ func OpSstore(pc *uint64, env EVMEnvironment, scope ScopeContext) ([]byte, error
 	oldValHash := env.GetState(scope.GetContract().Address(), common.Hash(loc.Bytes32()))
 	// If the value is the same or if we are not going to commit, don't do anything to protected storage.
 	if newValHash != oldValHash && env.IsCommitting() {
-		protectedStorage := ps.CreateProtectedStorageContractAddress(scope.GetContract().Address())
+		protectedStorage := fhevm_crypto.CreateProtectedStorageContractAddress(scope.GetContract().Address())
 
 		// Define flag location as keccak256(keccak256(loc)) in protected storage. Used to mark the location as containing a handle.
 		// Note: We apply the hash function twice to make sure a flag location in protected storage cannot clash with a ciphertext
@@ -352,3 +353,14 @@ func OpReturn(pc *uint64, env EVMEnvironment, scope ScopeContext) []byte {
 	delegateCiphertextHandlesToCaller(env, ret)
 	return ret
 }
+
+func OpSelfdestruct(pc *uint64, env EVMEnvironment, scope ScopeContext) (beneficiary uint256.Int, balance *big.Int) {
+	beneficiary = scope.GetStack().Pop()
+	protectedStorage := fhevm_crypto.CreateProtectedStorageContractAddress(scope.GetContract().Address())
+	balance = env.GetBalance(scope.GetContract().Address())
+	balance.Add(balance, env.GetBalance(protectedStorage))
+	env.AddBalance(beneficiary.Bytes20(), balance)
+	env.Suicide(scope.GetContract().Address())
+	env.Suicide(protectedStorage)
+	return
+}
diff --git a/fhevm/interface.go b/fhevm/interface.go
index ca3f3b4..75c8285 100644
--- a/fhevm/interface.go
+++ b/fhevm/interface.go
@@ -12,6 +12,10 @@ type EVMEnvironment interface {
 	GetState(common.Address, common.Hash) common.Hash
 	SetState(common.Address, common.Hash, common.Hash)
 	GetNonce(common.Address) uint64
+	AddBalance(common.Address, *big.Int)
+	GetBalance(common.Address) *big.Int
+
+	Suicide(common.Address) bool
 
 	// EVM call stack depth
 	GetDepth() int