SecKeyCopyKeyExchangeResult() 函数返回错误，“kSecKeyKeyExchangeParameterRequestedSize 丢失”

Question

我使用 Xcode11 Beta 作为 IDE 和 Swift。

下面是我的代码，我的代码在Xcode10.3上可以很好地工作，但在Xcode11上却不能工作。当我调用函数 SecKeyCopyKeyExchangeResult() 时，堆栈总是返回错误“kSecKeyKeyExchangeParameterRequestedSize is Missing”，但在 Xcode10.3 上没问题。我检查了苹果开发者门户，没有任何线索。

`
函数主() {

    testECDH()
}

private func testECDH(){
    generateKeyPair()
    let alicePublicKey = getPublicKey()
    let alicePrivateKey = getPrivateKey()
    print(alicePublicKey)
    print(alicePrivateKey)

    generateKeyPair()
    let bobPublicKey = getPublicKey()
    let bobPrivateKey = getPrivateKey()
    print(bobPublicKey)
    print(bobPrivateKey)

    let alice_bob_ecdhsecret = ecdhSecretCalculation(publicKey: alicePublicKey, privateKey: bobPrivateKey)!
    let bob_alice_ecdhsecret = ecdhSecretCalculation(publicKey: bobPublicKey, privateKey: alicePrivateKey)!

    os_log("alice_bob_ecdhsecret = %@", alice_bob_ecdhsecret)
    os_log("bob_alice_ecdhsecret = %@", bob_alice_ecdhsecret)
}

private func generateKeyPair(){
    let attributes: [String: Any] = [kSecAttrKeySizeInBits as String: 256,
                                     kSecAttrKeyType as String: kSecAttrKeyTypeECSECPrimeRandom,
                                     kSecPrivateKeyAttrs as String: [kSecAttrIsPermanent as String: false],
                                     kSecPublicKeyAttrs as String:[kSecAttrIsPermanent as String: false]]

    var error: Unmanaged<CFError>?

    privateKey = SecKeyCreateRandomKey(attributes as CFDictionary, &error)!

    if privateKey != nil {
        publicKey = SecKeyCopyPublicKey(privateKey!)
    }


}

private func getPrivateKey()->SecKey{
    return privateKey!
}

private func getPublicKey()->SecKey{
    return publicKey!
}

private func ecdhSecretCalculation(publicKey: SecKey, privateKey: SecKey) -> NSData?
{
    var error: Unmanaged<CFError>?

    let keyPairAttr:[String : Any] = [kSecAttrKeySizeInBits as String: 256,
                                      kSecAttrKeyType as String: kSecAttrKeyTypeECSECPrimeRandom,
                                      kSecPrivateKeyAttrs as String: [kSecAttrIsPermanent as String: false],
                                      kSecPublicKeyAttrs as String:[kSecAttrIsPermanent as String: false]]
    let algorithm:SecKeyAlgorithm = SecKeyAlgorithm.ecdhKeyExchangeStandardX963SHA256//ecdhKeyExchangeStandardX963SHA256

    let shared:CFData? = SecKeyCopyKeyExchangeResult(privateKey, algorithm, publicKey, keyPairAttr as! CFDictionary, &error)

    return shared
}`

Answer 1

我只是通过下面的代码片段解决了这个问题

let keyPairAttr:[String : Any] = [kSecAttrKeySizeInBits as String: 256,

                                      SecKeyKeyExchangeParameter.requestedSize.rawValue as String: 32,
                                      kSecAttrKeyType as String: kSecAttrKeyTypeECSECPrimeRandom,
                                      kSecPrivateKeyAttrs as String: [kSecAttrIsPermanent as String: false],
                                      kSecPublicKeyAttrs as String:[kSecAttrIsPermanent as String: false]]
    let algorithm:SecKeyAlgorithm = SecKeyAlgorithm.ecdhKeyExchangeStandardX963SHA256//ecdhKeyExchangeStandardX963SHA256

    let shared:CFData? = SecKeyCopyKeyExchangeResult(privateKey, algorithm, publicKey, keyPairAttr as! CFDictionary, &error)

请注意，下面是我添加的用于解决此问题的代码：

SecKeyKeyExchangeParameter.requestedSize.rawValue as String: 32,