IOS https authentication

Question

I want my application to authenticate against appliance i.e passing username and password over https.

I looked at few examples and basically build the following:

Answer 1

You must use NSURLConnectionDelegate delegate to handle NSURLConnection events.

For authentication there are two delegates methods:connection:canAuthenticateAgainstProtectionSpace: and connection:didReceiveAuthenticationChallenge:

See examples in URL Loading System Programming Guide

Answer 2

When making a request requiring authentication, you will receive a callback to didReceiveAuthenticationChallenge, which you handle as follows:

-(void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
   if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
   {
       if ([challenge.protectionSpace.host isEqualToString:MY_PROTECTION_SPACE_HOST])
       {
           [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
       }

       [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
   }
   else if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic])
   {
      if ([challenge previousFailureCount] == 0)
      {
          NSURLCredential *newCredential;

          newCredential = [NSURLCredential credentialWithUser:MY_USERNAME
                        password:MY_PASSWORD
                        persistence:NSURLCredentialPersistenceForSession];

          [[challenge sender] useCredential:newCredential forAuthenticationChallenge:challenge];
      }
      else
      {
          [[challenge sender] cancelAuthenticationChallenge:challenge];

          // inform the user that the user name and password
          // in the preferences are incorrect

          NSLog (@"failed authentication");

          // ...error will be handled by connection didFailWithError
      }
  }
}