Add cast/decrypt and hardcoded keys

fhevm/evm.go

@@ -44,19 +44,19 @@ func makeKeccakSignature(input string) uint32 {
 	return binary.BigEndian.Uint32(crypto.Keccak256([]byte(input))[0:4])
 }
 
-func isScalarOp(environment *EVMEnvironment, input []byte) (bool, error) {
+func isScalarOp(input []byte) (bool, error) {
 	if len(input) != 65 {
 		return false, errors.New("input needs to contain two 256-bit sized values and 1 8-bit value")
 	}
 	isScalar := (input[64] == 1)
 	return isScalar, nil
 }
 
-func getVerifiedCiphertext(environment *EVMEnvironment, ciphertextHash common.Hash) *verifiedCiphertext {
-	return getVerifiedCiphertextFromEVM(*environment, ciphertextHash)
+func getVerifiedCiphertext(environment EVMEnvironment, ciphertextHash common.Hash) *verifiedCiphertext {
+	return getVerifiedCiphertextFromEVM(environment, ciphertextHash)
 }
 
-func get2VerifiedOperands(environment *EVMEnvironment, input []byte) (lhs *verifiedCiphertext, rhs *verifiedCiphertext, err error) {
+func get2VerifiedOperands(environment EVMEnvironment, input []byte) (lhs *verifiedCiphertext, rhs *verifiedCiphertext, err error) {
 	if len(input) != 65 {
 		return nil, nil, errors.New("input needs to contain two 256-bit sized values and 1 8-bit value")
 	}
@@ -72,7 +72,7 @@ func get2VerifiedOperands(environment *EVMEnvironment, input []byte) (lhs *verif
 	return
 }
 
-func getScalarOperands(environment *EVMEnvironment, input []byte) (lhs *verifiedCiphertext, rhs *big.Int, err error) {
+func getScalarOperands(environment EVMEnvironment, input []byte) (lhs *verifiedCiphertext, rhs *big.Int, err error) {
 	if len(input) != 65 {
 		return nil, nil, errors.New("input needs to contain two 256-bit sized values and 1 8-bit value")
 	}
@@ -85,8 +85,8 @@ func getScalarOperands(environment *EVMEnvironment, input []byte) (lhs *verified
 	return
 }
 
-func importCiphertextToEVMAtDepth(environment *EVMEnvironment, ct *tfheCiphertext, depth int) *verifiedCiphertext {
-	existing, ok := (*environment).GetFhevmData().verifiedCiphertexts[ct.getHash()]
+func importCiphertextToEVMAtDepth(environment EVMEnvironment, ct *tfheCiphertext, depth int) *verifiedCiphertext {
+	existing, ok := environment.GetFhevmData().verifiedCiphertexts[ct.getHash()]
 	if ok {
 		existing.verifiedDepths.add(depth)
 		return existing
@@ -97,21 +97,21 @@ func importCiphertextToEVMAtDepth(environment *EVMEnvironment, ct *tfheCiphertex
 			verifiedDepths,
 			ct,
 		}
-		(*environment).GetFhevmData().verifiedCiphertexts[ct.getHash()] = new
+		environment.GetFhevmData().verifiedCiphertexts[ct.getHash()] = new
 		return new
 	}
 }
 
-func importCiphertextToEVM(environment *EVMEnvironment, ct *tfheCiphertext) *verifiedCiphertext {
-	return importCiphertextToEVMAtDepth(environment, ct, (*environment).GetDepth())
+func importCiphertextToEVM(environment EVMEnvironment, ct *tfheCiphertext) *verifiedCiphertext {
+	return importCiphertextToEVMAtDepth(environment, ct, environment.GetDepth())
 }
 
-func importCiphertext(environment *EVMEnvironment, ct *tfheCiphertext) *verifiedCiphertext {
+func importCiphertext(environment EVMEnvironment, ct *tfheCiphertext) *verifiedCiphertext {
 	return importCiphertextToEVM(environment, ct)
 }
 
-func importRandomCiphertext(environment *EVMEnvironment, t fheUintType) []byte {
-	nextCtHash := &(*environment).GetFhevmData().nextCiphertextHashOnGasEst
+func importRandomCiphertext(environment EVMEnvironment, t fheUintType) []byte {
+	nextCtHash := &environment.GetFhevmData().nextCiphertextHashOnGasEst
 	ctHashBytes := crypto.Keccak256(nextCtHash.Bytes())
 	handle := common.BytesToHash(ctHashBytes)
 	ct := new(tfheCiphertext)
@@ -129,3 +129,40 @@ func minInt(a int, b int) int {
 	}
 	return b
 }
+
+// Return a memory with a layout that matches the `bytes` EVM type, namely:
+//   - 32 byte integer in big-endian order as length
+//   - the actual bytes in the `bytes` value
+//   - add zero byte padding until nearest multiple of 32
+func toEVMBytes(input []byte) []byte {
+	arrLen := uint64(len(input))
+	lenBytes32 := uint256.NewInt(arrLen).Bytes32()
+	ret := make([]byte, 0, arrLen+32)
+	ret = append(ret, lenBytes32[:]...)
+	ret = append(ret, input...)
+	return ret
+}
+
+func InitFhevm(accessibleState EVMEnvironment) {
+	persistFhePubKeyHash(accessibleState)
+}
+
+func persistFhePubKeyHash(accessibleState EVMEnvironment) {
+	existing := accessibleState.GetState(fhePubKeyHashPrecompile, fhePubKeyHashSlot)
+	if newInt(existing[:]).IsZero() {
+		accessibleState.SetState(fhePubKeyHashPrecompile, fhePubKeyHashSlot, pksHash)
+	}
+}
+
+// apply padding to slice to the multiple of 32
+func padArrayTo32Multiple(input []byte) []byte {
+	modRes := len(input) % 32
+	if modRes > 0 {
+		padding := 32 - modRes
+		for padding > 0 {
+			padding--
+			input = append(input, 0x0)
+		}
+	}
+	return input
+}

fhevm/interface.go

@@ -33,3 +33,10 @@ type FhevmData struct {
 
 	nextCiphertextHashOnGasEst uint256.Int
 }
+
+func NewFhevmData() FhevmData {
+	return FhevmData{
+		verifiedCiphertexts: make(map[common.Hash]*verifiedCiphertext),
+		optimisticRequires:  make([]*tfheCiphertext, 0),
+	}
+}