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My goal is: Generate a public and private key pair Add the private key to the keychain and protect it with the secure enclave Create a self-signed certificate with the public key and send it to a server Add the certificate to the keychain When I communicate with the server I want to create a SecIdentity during the client challenge which is basically a SecCertificate + SecKey combo. For the certificate generation I would like to use the swift-certificates library to not have to compose manually the certificate fields and signature. My problem is that the swift-certificates during the Certificate initialisation needs a SecureEnclave.P256.Signing.PrivateKey private key and to add a key to the keychain we need a SecKey object. And unfortunately there is no clean way to create from one of them the other one. I read several threads here about this, but I haven't found a clean solution for it. I tried to approach the problem from two directions: First: Create the key with the SecKeyCreateRandomKey, mark in the attributes that I want to protect the key with secure enclave and also mark that I want the private key to be kSecAttrIsPermanent so it is automatically saved in the keychain The SecKeyCreateRandomKey returns a SecKey which is a reference to the private key from the keychain (!) Unfortunately I haven't found a clean way to convert a SecKey to a -> SecureEnclave.P256.Signing.PrivateKey There is a workaround to SecKeyCopyAttributes of the private key and to extract the bytes from the attributes["toid"], but I guess it's not safe to use an undocumented key ("toid") if there is no constant defined to it (the name could be changed in future releases) Second approach: Create a SecureEnclave.P256.Signing.PrivateKey Create the Certificate using the swift-certificates The created private key is protected by the secure enclave but it's not added automatically to the keychain so we should add it to can query after that the SecIdentity (!) Unfortunately I haven't found a way to convert the SecureEnclave.P256.Signing.PrivateKey to -> SecKey. There are threads which say that the SecKeyCreateWithData(...) helps us, but unfortunately if we set the kSecAttrTokenIDSecureEnclave in the attribute dictionary, the method creates a brand new key for us, regardless the passed data. So the initial key will never be the same as the newly created SecKey. This we can see in the method's implementation. So I got stuck with both approaches because seemingly there is no clean way to switch between SecureEnclave.P256.Signing.PrivateKey and SecKey. One solution would be to compose manually the certificate, without swift-certificates because like that we would not need a SecureEnclave.P256.Signing.PrivateKey object. But I would like to avoid the manual composition and signature calculation... Anybody has any idea?