How https request is handling using NSURLConnection

Question

Can anybody help me to know how https request are processing using NSRULConnection? I had gone through lot of tutorials and Apple documentation. But I am not able to understand how it is working. I have implemented the following delegates to process an https request.

- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace 
{    
    return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];
}

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

When I implemented the above delegate, I got response from the server successfully. Can anyone help me to know how this is working. Also what are each parameters in the delegate and what it is doing?

Thanks in advance.

Answer 1

Think of the protectionSpace as the server. The delegate method connection: canAuthenticateAgainstProtectionSpace is used to ask you if you can handle the authentication requirements of the server. In your case, you say "if we're talking about the SSL certificate (that's what NSURLAuthenticationMethodServerTrust usually means), yes, I can handle that".

The connection then asks you to do just that with connection:didReceiveAuthenticationChallenge and provide a NSURLCredential for this specific server. With credentialForTrust: you create the credential by using the information stored in your keychain for the certificate of this server. With useCredential:forAuthenticationChallenge: you finally tell the connection to answer the challenge with this credential, i.e. use the keychain data to validate the certificate.

Answer 2

This example will help you How To Use iOS NSURLConnection By Example