ios - 如何使用 swift 将 VPN 服务器与我们的 iOS 应用程序连接

Question

我想将 VPN 服务器与我的 iOS 应用程序连接。我无法与 VPN 服务器建立连接。我对此进行了很多搜索，但没有得到任何解决方案。

这是我的代码：

import UIKit
import NetworkExtension
import Security

class VPN
{
   static let shared = VPN()
    let vpnManager = NEVPNManager.shared()
    private var vpnLoadHandler: (Error?) -> Void { return
    { (error:Error?) in
        if ((error) != nil) {
            print("Could not load VPN Configurations")
            return;
        }



        let p = NEVPNProtocolIPSec()
        p.username = UserDefaults.standard.string(forKey: "uname")
        p.serverAddress = UserDefaults.standard.string(forKey: "server")

        p.authenticationMethod = NEVPNIKEAuthenticationMethod.sharedSecret

            p.passwordReference = UserDefaults.standard.string(forKey: "pwd")?.data(using: .utf8)!

            p.useExtendedAuthentication = true
            p.disconnectOnSleep = true
            self.vpnManager.protocolConfiguration = p
            self.vpnManager.localizedDescription = "Contensi"
            self.vpnManager.isEnabled = true
        self.vpnManager.saveToPreferences(completionHandler: nil)
            }

    }

    private var vpnSaveHandler: (Error?) -> Void { return
    {
        (error:Error?) in
        if (error != nil) {
            print("Could not save VPN Configurations")
            return
        } else
        {
            do
            {
                try self.vpnManager.connection.startVPNTunnel()
            } catch let error
            {
                print("Error starting VPN Connection \(error.localizedDescription)");
            }
        }
        }
//        self.vpnlock = false
    }
    public func connectVPN() {

        do
        {
            try self.vpnManager.loadFromPreferences(completionHandler: self.vpnLoadHandler)
        } catch let error
        {
            print("Could not start VPN Connection: \(error.localizedDescription)" )
        }
    }

    public func disconnectVPN() ->Void {
        vpnManager.connection.stopVPNTunnel()
    }

class VPNViewController: UIViewController
{
    override func viewDidLoad()
    {
        super.viewDidLoad()

    }

}