Open Radar

 
Summary:
I'm seeing an assertion failure in the iPhone Captive Network WebSheet when a Wi-Fi network is set up with an automatic Proxy PAC URL.

Specifically, the logs show (line #12 in attached iPhone console log):
iPhone WebSheet[426] <Error>: assertion failed: 12F70: libxpc.dylib + 71768 [B870B51D-AA85-3686-A7D9-ACD48C5FE153]: 0x7d

The result is that the web sheet doesn't even make a request to the identified captive network redirect page (we can see this from the server side) and shows a blank screen to the user, followed eventually by an alert saying "Error Opening Page / Hotspot login could not open the page because the server stopped responding."

We also see no request to the Proxy PAC URL during this process (see attached apache web logs).

Steps to Reproduce:
1. Set up a captive network with a Proxy PAC URL accessible within the walled garden
2. Find the SSID in the iPhone's Wi-Fi network list and press the (i) to get the Wi-Fi settings
3. Select Auto from the HTTP Proxy section and input the Proxy PAC URL
4. Attempt to Join the network

Expected Results:
The Captive Network web sheet should appear and display the captive network's login page. Also the iPhone should call the Proxy PAC URL.

Actual Results:
The Captive Network web sheet appears but is blank and times out after 1 minute with the following alert: "Error Opening Page / Hotspot login could not open the page because the server stopped responding."

Also the Proxy PAC URL is not called

Version:
iOS 8.3 (12F70)

Notes:


Configuration:
iPhone 6 64Gb using WiFi