Extract Data from P8 file

Hi,

I am trying to extract the data from the P8 file to use it generate JWT.

I understand that it is possible using dumpasn1 and extracting the OCTET STRING section. This is great, and is definitely possible.

I was wondering if it was possible to do it on macOS using Apple's APIs (example SecItemImport), would make it simpler if it was possible all in the mac app.

I tried the following but it didn't work:

Error:

I got the OSStatus as -25257

Questions:

- Is there a way to do this using SecItemImport or any other Apple APIs as I am using it in a command line mac app ?

- Are the parameters to SecItemImport are incorrect ?

- Am down the wrong path? , any direction to the correct API would help.

What I tried with SecItemImport:

- Data extracted from the file

- Decoding the data from the file

- Some input formats

Many thanks.

import Foundation
import Security

func f1() {
    
    do {
        let fileURL = URL(fileURLWithPath: "some valid path");
        
        let data = try Data(contentsOf: fileURL)
        
        guard let string = String(data: data, encoding: .utf8) else {
            print("Failed to convert data to string")
            return
        }
        
        let b64Text = string
            .replacingOccurrences(of: "-----END PRIVATE KEY-----", with: "")
            .replacingOccurrences(of: "-----BEGIN PRIVATE KEY-----", with: "")
            .replacingOccurrences(of: "\n", with: "")
        
        guard let b64Data = b64Text.data(using: .utf8),
            let decodedData = Data(base64Encoded: b64Data) else {
            print("Was not b64 data")
            return
        }
        
        print(string)
        
        
        var outArray : CFArray?
        let filename : CFString? = nil
        var inputFormat = SecExternalFormat.formatUnknown
        var itemType = SecExternalItemType.itemTypePrivateKey
        let flags = SecItemImportExportFlags()
        
        //I tried data, b64Data, decodedData all seems to return an error
        let status = SecItemImport(decodedData as CFData,
                                   filename,
                                   &inputFormat,
                                   &itemType,
                                   flags,
                                   nil,
                                   nil,
                                   &outArray)
        
        //status = -25257
        
        print("status = \(status)")
        
        for element in (outArray as [AnyObject]?) ?? [] {
            
            print("element = \(element)")
        }
    }
    catch {
        print("Error: \(error)")
    }
}

f1()