chore: fix decryption

fhevm/tee_crypto.go

@@ -131,20 +131,30 @@ func teeOptimisticRequireRun(environment EVMEnvironment, caller common.Address,
 // one 0, the result will be 0 (false).
 func teeEvaluateRemainingOptimisticRequires(environment EVMEnvironment) (bool, error) {
 	requires := environment.FhevmData().optimisticRequires
-	len := len(requires)
+	length := len(requires)
 	defer func() { environment.FhevmData().resetTeeOptimisticRequires() }()
-	if len != 0 {
+	if length != 0 {
 		var cumulative *tfhe.TfheCiphertext = requires[0]
 		var err error
-		for i := 1; i < len; i++ {
+		for i := 1; i < length; i++ {
 			cumulative, err = cumulative.Bitand(requires[i])
 			if err != nil {
 				environment.GetLogger().Error("evaluateRemainingOptimisticRequires bitand failed", "err", err)
 				return false, err
 			}
 		}
-		result, err := decryptValue(environment, cumulative)
-		return result != 0, err
+		result, err := tee.Decrypt(cumulative)
+		if err != nil {
+			return false, err
+		}
+
+		plaintext := result.Value
+		// Always return a 32-byte big-endian integer.
+		ret := make([]byte, 32)
+		copy(ret[32-len(plaintext):], plaintext)
+
+		retVal := *new(big.Int).SetBytes(ret)
+		return retVal.Uint64() != 0, err
 	}
 	return true, nil
 }

fhevm/tee_crypto_test.go

@@ -46,3 +46,41 @@ func TestTeeDecryptRun(t *testing.T) {
 		}
 	})
 }
+
+func TestTeeOptimisticRequire(t *testing.T) {
+	signature := "teeOptimisticRequire(uint256)"
+	// func teeOptimisticRequireRun(environment EVMEnvironment, caller common.Address, addr common.Address, input []byte, readOnly bool, runSpan trace.Span) ([]byte, error) {
+
+	rapid.Check(t, func(t *rapid.T) {
+		testcases := []struct {
+			typ     tfhe.FheUintType
+			require uint64
+		}{
+			{tfhe.FheUint8, uint64(1)},
+			{tfhe.FheUint8, uint64(1)},
+		}
+
+		environment := newTestEVMEnvironment()
+		depth := 1
+		environment.depth = depth
+		for _, tc := range testcases {
+			addr := common.Address{}
+			readOnly := false
+			ct, err := importTeePlaintextToEVM(environment, depth, tc.require, tc.typ)
+			if err != nil {
+				t.Fatalf(err.Error())
+			}
+
+			input := toLibPrecompileInput(signature, false, ct.GetHash())
+			_, err = FheLibRun(environment, addr, addr, input, readOnly)
+			if err != nil {
+				t.Fatalf(err.Error())
+			}
+		}
+
+		optReqResult, _ := teeEvaluateRemainingOptimisticRequires(environment)
+		if !optReqResult {
+			t.Fatalf("incorrect result, expected=%d, got=0", 1)
+		}
+	})
+}