URLSession Delegate for authentication challenge

NSURLSessionDelegate.swift

func URLSession(session: NSURLSession, didReceiveChallenge challenge: NSURLAuthenticationChallenge, completionHandler: (NSURLSessionAuthChallengeDisposition, NSURLCredential?) -> Void) {

    if challenge.protectionSpace.authenticationMethod == (NSURLAuthenticationMethodServerTrust) {


    let serverTrust:SecTrustRef = challenge.protectionSpace.serverTrust!
    let certificate: SecCertificateRef = SecTrustGetCertificateAtIndex(serverTrust, 0)!
    let remoteCertificateData = CFBridgingRetain(SecCertificateCopyData(certificate))!
    let cerPath: String = NSBundle.mainBundle().pathForResource("xyz.com", ofType: "cer")!
    let localCertificateData = NSData(contentsOfFile:cerPath)!


        if (remoteCertificateData.isEqualToData(localCertificateData) == true) {
            let credential:NSURLCredential = NSURLCredential(forTrust: serverTrust)

            challenge.sender?.useCredential(credential, forAuthenticationChallenge: challenge)


            completionHandler(NSURLSessionAuthChallengeDisposition.UseCredential, NSURLCredential(forTrust: challenge.protectionSpace.serverTrust!))

        } else {

            completionHandler(NSURLSessionAuthChallengeDisposition.CancelAuthenticationChallenge, nil)
        }
    }
    else if challenge.protectionSpace.authenticationMethod == NSURLAuthenticationMethodClientCertificate
    {

        let path: String = NSBundle.mainBundle().pathForResource("client", ofType: "p12")!
        let PKCS12Data = NSData(contentsOfFile:path)!


        let identityAndTrust:IdentityAndTrust = self.extractIdentity(PKCS12Data);



            let urlCredential:NSURLCredential = NSURLCredential(
                identity: identityAndTrust.identityRef,
                certificates: identityAndTrust.certArray as? [AnyObject],
                persistence: NSURLCredentialPersistence.ForSession);

            completionHandler(NSURLSessionAuthChallengeDisposition.UseCredential, urlCredential);




    }
    else
    {
        completionHandler(NSURLSessionAuthChallengeDisposition.CancelAuthenticationChallenge, nil);
    }
}

 struct IdentityAndTrust {

    var identityRef:SecIdentityRef
    var trust:SecTrustRef
    var certArray:AnyObject
}

func extractIdentity(certData:NSData) -> IdentityAndTrust {
    var identityAndTrust:IdentityAndTrust!
    var securityError:OSStatus = errSecSuccess

    let path: String = NSBundle.mainBundle().pathForResource("client", ofType: "p12")!
    let PKCS12Data = NSData(contentsOfFile:path)!
    let key : NSString = kSecImportExportPassphrase as NSString
    let options : NSDictionary = [key : "xyz"]
    //create variable for holding security information
    //var privateKeyRef: SecKeyRef? = nil

    var items : CFArray?

     securityError = SecPKCS12Import(PKCS12Data, options, &items)

    if securityError == errSecSuccess {
        let certItems:CFArray = items as CFArray!;
        let certItemsArray:Array = certItems as Array
        let dict:AnyObject? = certItemsArray.first;
        if let certEntry:Dictionary = dict as? Dictionary<String, AnyObject> {

            // grab the identity
            let identityPointer:AnyObject? = certEntry["identity"];
            let secIdentityRef:SecIdentityRef = identityPointer as! SecIdentityRef!;
            print("\(identityPointer)  :::: \(secIdentityRef)")
            // grab the trust
            let trustPointer:AnyObject? = certEntry["trust"];
            let trustRef:SecTrustRef = trustPointer as! SecTrustRef;
            print("\(trustPointer)  :::: \(trustRef)")
            // grab the cert
            let chainPointer:AnyObject? = certEntry["chain"];
            identityAndTrust = IdentityAndTrust(identityRef: secIdentityRef, trust: trustRef, certArray:  chainPointer!);
        }
    }
    return identityAndTrust;
}