CryptoKit/不能使用SymmetricKey(data:)初始化SymmetricKey ?

Question

我试图从自定义字符串创建symmetricKey。当我使用SymmetricKey(size:)时，我的代码工作得很好，但是我想从自定义字符串创建symmetricKey，所以我使用SymmetricKey(data:)。我不知道我的代码出了什么问题。

func encryptAccessToken(with accessToken: String) {
guard #available(iOS 13.0, *) else  { return }
guard  let keyData = "myStringKey".data(using: .utf8), let data = accessToken.data(using: .utf8) else { return }
let symmetricKey = SymmetricKey(data: keyData)
do {
let encryptedData = try AES.GCM.seal(data, using: symmetricKey).combined
UserDefaults.standard.set(encryptedData, forKey: secretKey)
} catch {
print("(error.localizedDescription)")
}
}

Answer 1

我自己回答了这个问题，这里的答案可能有人需要。

func encryptAccessToken(with accessToken: String) {
guard #available(iOS 13.0, *) else  { return }
guard let data = accessToken.data(using: .utf8) else { return }
let myString = "myString"
let keyData = SHA256.hash(data: myString.data(using: .utf8)!)
let symmetricKey = SymmetricKey(data: keyData)
do {
let encryptedData = try AES.GCM.seal(data, using: symmetricKey).combined
UserDefaults.standard.set(encryptedData, forKey: secretKey)
} catch {
print("(error.localizedDescription)")
}
}