How does Windows decide whether your computer has full Internet access? • Hacker News Board

Re: How does Windows decide whether your computer has full Internet access?

#31

Post by fegu » Sat, Nov 19, 2022, 2:04 AM UTC

eightysixfour wrote: post #27

jasonzemos wrote: post #7

Is it a problem that the URL is not HTTPS or is it the blessing required to defeat it?

I realized a while back that msftconnecttest.com is the domain it uses to check online status, and is the domain it checks in the background that gets redirected to wifi captive portals and pulls up. Any time I have an issue with a captive portal, I use that domain and the redirect works, because I know any other URL with end up with a certificate issue and I won’t be able to get to the portal.

This is why neverssl.com exists. I always use that when I need the login page of a wifi.

Re: How does Windows decide whether your computer has full Internet access?

#32

Post by dahdum » Sat, Nov 19, 2022, 2:06 AM UTC

gerdesj wrote: post #11

This really gets on my nerves! Some twit of a programmer (probably via a committee) "knows" whether a system has connectivity. For some people Facebook is the internet and for others it is Outlook. Somehow a twiddler at MS has decided that a file on a web server at some wanky location is the internet and that's the final answer. "I cn haz a file" is fine lovely internets! No it bloody well isn't. You should be constr…

> I run quite a few systems/sites that have multiple internet connections - deciding whether the internet is available is quite a nuanced thing and that Windows internet detector is bloody stupid, naive and a fucking hindrance.

I'm not following this, where is the nuance? What problems does this cause and why are they so difficult to solve? Even if behind a strict firewall that allows only a few IPs or ranges (arguable that would still be the "internet" as commonly understood), couldn't you just override DNS to return the same file from your server?

I've been annoyed by iOS disconnecting from wifi when no access is detected and I'm just trying to stream something from local network, but not Windows.

Re: How does Windows decide whether your computer has full Internet access?

#33

Post by moduspol » Sat, Nov 19, 2022, 2:07 AM UTC

rkagerer wrote: post #12

YPPH wrote: post #9

Earlier quoted context omitted.

One reason for that is explained well in a comment on the article. Note that as with the Windows version, the protocol is HTTP, not HTTPS – because captive portals completely break TLS, but plaintext HTTP will result in a clean redirect to the portal, allowing the network service to detect the presence of the portal and to bring up a browser window to let the user authenticate. ( https://devblogs.microsoft.com/oldnew…

Yeah, and there's also no guarantee the computer's certificates are even up to date (eg. first time you connect a PC after a fresh install off older media)

Also no guarantee the computer's clock is set ballpark accurately (which TLS requires), which can be relevant if Windows is checking for Internet connectivity before (for example) using NTP to update the computer's clock.

Re: How does Windows decide whether your computer has full Internet access?

#34

Post by Kuinox » Sat, Nov 19, 2022, 2:09 AM UTC

eightysixfour wrote: post #27

jasonzemos wrote: post #7

Is it a problem that the URL is not HTTPS or is it the blessing required to defeat it?

I realized a while back that msftconnecttest.com is the domain it uses to check online status, and is the domain it checks in the background that gets redirected to wifi captive portals and pulls up. Any time I have an issue with a captive portal, I use that domain and the redirect works, because I know any other URL with end up with a certificate issue and I won’t be able to get to the portal.

http://example.com will forever be http.

Re: How does Windows decide whether your computer has full Internet access?

#35

Post by cronin101 » Sat, Nov 19, 2022, 2:09 AM UTC

throwaway0x7E6 wrote: post #30

photoGrant wrote: post #2

Doing this during a Windows 11 install will result in a road block until you fix said connection issues. You literally can't proceed without finding a hidden terminal and disabling the process and restarting. Insane.

even with the cable unplugged and no wifi module?

Yes, can confirm I was installing Win11 on my brother-in-law's new PC that I built last week and there were no default drivers for the USB wifi adapter I had attempted to reuse from his old machine. The entire process was roadblocked wanting me to plug into Ethernet until I researched the secret keyboard combination that allows you to shell out and then restart with the ability to do a network-free install.

Re: How does Windows decide whether your computer has full Internet access?

#36

Post by meltyness » Sat, Nov 19, 2022, 2:11 AM UTC

This is sort of a nightmare since, at least on Windows 10, this is determined differently for different facilities.

I'm in a situation where I needed to modify my Registry https://learn.microsoft.com/en-us/windows/win32/cimwin32prov... in order to convince the Metro UI that I was actually connected, whereas everything else was working fine.

I can't remember exactly what I did now, but it's been working great.

Re: How does Windows decide whether your computer has full Internet access?

#37

Post by empyrrhicist » Sat, Nov 19, 2022, 2:11 AM UTC

cronin101 wrote: post #35

throwaway0x7E6 wrote: post #30

Earlier quoted context omitted.

even with the cable unplugged and no wifi module?

Yes, can confirm I was installing Win11 on my brother-in-law's new PC that I built last week and there were no default drivers for the USB wifi adapter I had attempted to reuse from his old machine. The entire process was roadblocked wanting me to plug into Ethernet until I researched the secret keyboard combination that allows you to shell out and then restart with the ability to do a network-free install.

Madness

Re: How does Windows decide whether your computer has full Internet access?

#38

Post by httpz » Sat, Nov 19, 2022, 2:11 AM UTC

I'm not sure if it's still in use but iPhones used to hit http://www.apple.com/library/test/success.html to test connectivity.

I used to use it to test connectivity on my own apps because Apple is probably better at making sure a url reachable than I am.

Re: How does Windows decide whether your computer has full Internet access?

#39

Post by hsbauauvhabzb » Sat, Nov 19, 2022, 2:12 AM UTC

Two things I’ve always wanted to do is figure out how to cache windows updates on my local network without an enterprise windows install, and how to block windows updates by sinkholing domains and/or ip addresses (I work in IT security).

Can anyone give any tips on either of these?

Re: How does Windows decide whether your computer has full Internet access?

#40

Post by throwaway0x7E6 » Sat, Nov 19, 2022, 2:14 AM UTC

cronin101 wrote: post #35

throwaway0x7E6 wrote: post #30

Earlier quoted context omitted.

even with the cable unplugged and no wifi module?

Yes, can confirm I was installing Win11 on my brother-in-law's new PC that I built last week and there were no default drivers for the USB wifi adapter I had attempted to reuse from his old machine. The entire process was roadblocked wanting me to plug into Ethernet until I researched the secret keyboard combination that allows you to shell out and then restart with the ability to do a network-free install.

No post body was provided.