system/CodeIgniter.php
protected function forceSecureAccess($duration = 31536000)
	{
		if ($this->config->forceGlobalSecureRequests !== true)
		{
			return;
		}

		force_https($duration, $this->request, $this->response);
	}
protected function forceSecureAccess($duration = 31536000)
	{
		if ($this->config->forceGlobalSecureRequests !== true)
		{
			return;
		}

		force_https($duration, $this->request, $this->response);
	}
Force Secure Site Access? If the config value 'forceGlobalSecureRequests'
is true, will enforce that all requests to this site are made through
HTTPS. Will redirect the user to the current page with HTTPS, as well
as set the HTTP Strict Transport Security header for those browsers
that support it.

@param integer $duration How long the Strict Transport Security
should be enforced for this URL.