In Swift, I created a SecKeyRef object by calling SecTrustCopyPublicKey on some raw X509 certificate data. This is what this SecKeyRef object looks like.
From How do I encode an unmanaged
func convertSecKeyToBase64(inputKey: SecKey) ->String? {
// Add to keychain
let tempTag = "net.example." + NSUUID().UUIDString
let addParameters :[String:AnyObject] = [
String(kSecClass): kSecClassKey,
String(kSecAttrApplicationTag): tempTag,
String(kSecAttrKeyType): kSecAttrKeyTypeRSA,
String(kSecValueRef): inputKey,
String(kSecReturnData):kCFBooleanTrue
]
var result: String?
var keyPtr: AnyObject?
if (SecItemAdd(addParameters, &keyPtr) == noErr) {
let data = keyPtr! as! NSData
result = data.base64EncodedStringWithOptions(NSDataBase64EncodingOptions(rawValue: 0))
}
// Remove from Keychain:
SecItemDelete(addParameters)
return result
}
But if you want to avoid adding to keychain, you can use Mirror:
let mirrorKey = Mirror(reflecting: secKey)
let exponent = mirrorKey.descendant("exponent")
let modulus = mirrorKey.descendant("modulus");
[edit: Mirror not working according to Josh]