fix(tfhe): remove unsafe integer parsing (ethereum#98)

* fix(tfhe): remove unsafe integer parsing

* fix(tfhe): remove unused import

Author: tremblaythibaultl

core/vm/tfhe.go

@@ -410,7 +410,6 @@ import "C"
 
 import (
 	"crypto/rand"
-	"encoding/binary"
 	"errors"
 	"fmt"
 	"math/big"
@@ -545,19 +544,11 @@ func (ct *tfheCiphertext) encrypt(value big.Int, t fheUintType) {
 
 	switch t {
 	case FheUint8:
-		valBytes := [1]byte{}
-		value.FillBytes(valBytes[:])
-		ct.setPtr(C.client_key_encrypt_fhe_uint8(cks, C.uchar(valBytes[len(valBytes)-1])))
+		ct.setPtr(C.client_key_encrypt_fhe_uint8(cks, C.uchar(value.Uint64())))
 	case FheUint16:
-		valBytes := [2]byte{}
-		value.FillBytes(valBytes[:])
-		var valInt uint16 = binary.BigEndian.Uint16(valBytes[:])
-		ct.setPtr(C.client_key_encrypt_fhe_uint16(cks, C.ushort(valInt)))
+		ct.setPtr(C.client_key_encrypt_fhe_uint16(cks, C.ushort(value.Uint64())))
 	case FheUint32:
-		valBytes := [4]byte{}
-		value.FillBytes(valBytes[:])
-		var valInt uint32 = binary.BigEndian.Uint32(valBytes[:])
-		ct.setPtr(C.client_key_encrypt_fhe_uint32(cks, C.uint(valInt)))
+		ct.setPtr(C.client_key_encrypt_fhe_uint32(cks, C.uint(value.Uint64())))
 	}
 	ct.fheUintType = t
 	ct.value = &value