---
title: useClassicalSignature
framework: Security
role: symbol
role_heading: Type Property
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+]
path: security/seccsflags/useclassicalsignature
---

# useClassicalSignature

## Declaration

```swift
static var useClassicalSignature: SecCSFlags { get }
```

## Discussion

Discussion When passed to a validation or inspection call on a dual-signed code object, select the classical (RSA) signature slot for validation and information retrieval. Mutually exclusive with kSecCSUsePostQuantumSignature; passing both returns errSecCSInvalidFlags.