4 ms·

Not to be conspiratorial, but captive portals always felt like a little broken piece of internet technology that's never been fixed bc it benefits Google This

by geokon 3y ago

Not to be conspiratorial, but captive portals always felt like a little broken piece of internet technology that's never been fixed bc it benefits Google This has a very cryptic failure mode if you travel to China. Android will just tells you you can't connect to the internet :) It's pretty easy to work around. You just go to detectportal.firefox.com/ But naturally you need to know what's gone wrong in the first place !

izacus 3y ago
> Not to be conspiratorial, but captive portals always felt like a little broken piece of internet technology that's never been fixed bc it benefits Google Against my better judgement and for my grim fascination, I'd love to hear a full explanation of this conspiracy theory. Can you elaborate?
stavros 3y ago
How do captive portals benefit Google?
- acover 3y ago
  > But, why should I change it? > Well, on Android 6 or higher, every time you switch networks, your phone tries to access the following URL: > http://connectivitycheck.gstatic.com/generate_204 http://connectivitycheck.gstatic.com/generate_204 > As we can see, gstatic.com – Google’s servers. We might not want Google to know our new IP address or when we switched between networks. So… Why don’t we just self-host it? It’s pretty easy.
  - stavros 3y ago
    Yeah, that's not Google having a say on whether captive portals exist and deciding to keep them there, that's just Google deciding that it wants to know your IP whenever you connect to a network. I don't know why this is such a big issue, given that they have your more or less exact location at all times, but changing it is so easy that, why not.
    - duskwuff 3y ago
      > that's just Google deciding that it wants to know your IP whenever you connect to a network. No, it's Google wanting Android users to be notified when they sign in to a wifi network that uses a captive portal, rather than having all network requests silently fail because they're being redirected. Fixing the (generally terrible) user experience of captive portals is the primary goal of this feature. Any data collection is secondary.
  - charcircuit 3y ago
    Google already knows every IP address. There is a fixed amount. Anyone can send a request to that address. This doesn't give Google any new information either.
    - hackmiester 3y ago
      I guess that is true, but the IP address space today is so large as to be unscannable. Practically speaking, you have to have some evidence that some host is there before you can start prodding at that host.
      - philipkglass 3y ago
        Do you mean the IPv6 space? The full Ipv4 space has been practically scannable for quite a while now. https://zmap.io/ https://zmap.io/ ZMap is a fast single-packet network scanner optimized for Internet-wide network surveys. On a computer with a gigabit connection, ZMap can scan the entire public IPv4 address space on a single port in under 45 minutes. With a 10gigE connection and PF_RING, ZMap can scan the IPv4 address space in 5 minutes.
        hackmiester 3y ago
        Yes of course. Most devices on the Internet don't have IPv4 addresses.
  - lern_too_spel 3y ago
    gstatic.com is a cookieless domain. The persistent push connection needed by FCM (like APNS on iPhones) can tie the IP to a specific account, so this captive portal check gives them less information than they already have. Luckily on Android, you can use UnifiedPush and run your own push server to gain actual privacy.
kevincox 3y ago
> bc it benefits Google I doubt this is the reason. It seems more likely that no one has bothered to fix it. I agree that captive portals are a big hack with poor UX. This auto-detection does mitigate it but it is still very annoying especially if you have secure setups like encrypted DNS so the basic hijacking doesn't work properly.
Pxtl 3y ago
I find NeverSSL.com is a short, easy-to-remember URL for "oh crap am I in a captive portal or not".
_rdvw 3y ago
AOSP actually has handling when it detects a SIM MCC matching China: https://cs.android.com/android/platform/superproject/+/main:packages/modules/NetworkStack/res/values-mcc460/config.xml;l=1 https://cs.android.com/android/platform/superproject/+/main:...

by geokon 3y ago

izacus 3y ago

> Not to be conspiratorial, but captive portals always felt like a little broken piece of internet technology that's never been fixed bc it benefits Google Against my better judgement and for my grim fascination, I'd love to hear a full explanation of this conspiracy theory. Can you elaborate?

stavros 3y ago

How do captive portals benefit Google?

acover 3y ago
> But, why should I change it? > Well, on Android 6 or higher, every time you switch networks, your phone tries to access the following URL: > http://connectivitycheck.gstatic.com/generate_204 http://connectivitycheck.gstatic.com/generate_204 > As we can see, gstatic.com – Google’s servers. We might not want Google to know our new IP address or when we switched between networks. So… Why don’t we just self-host it? It’s pretty easy.
- stavros 3y ago
  Yeah, that's not Google having a say on whether captive portals exist and deciding to keep them there, that's just Google deciding that it wants to know your IP whenever you connect to a network. I don't know why this is such a big issue, given that they have your more or less exact location at all times, but changing it is so easy that, why not.
  - duskwuff 3y ago
    > that's just Google deciding that it wants to know your IP whenever you connect to a network. No, it's Google wanting Android users to be notified when they sign in to a wifi network that uses a captive portal, rather than having all network requests silently fail because they're being redirected. Fixing the (generally terrible) user experience of captive portals is the primary goal of this feature. Any data collection is secondary.
- charcircuit 3y ago
  Google already knows every IP address. There is a fixed amount. Anyone can send a request to that address. This doesn't give Google any new information either.
  - hackmiester 3y ago
    I guess that is true, but the IP address space today is so large as to be unscannable. Practically speaking, you have to have some evidence that some host is there before you can start prodding at that host.
    - philipkglass 3y ago
      Do you mean the IPv6 space? The full Ipv4 space has been practically scannable for quite a while now. https://zmap.io/ https://zmap.io/ ZMap is a fast single-packet network scanner optimized for Internet-wide network surveys. On a computer with a gigabit connection, ZMap can scan the entire public IPv4 address space on a single port in under 45 minutes. With a 10gigE connection and PF_RING, ZMap can scan the IPv4 address space in 5 minutes.
      - hackmiester 3y ago
        Yes of course. Most devices on the Internet don't have IPv4 addresses.
- lern_too_spel 3y ago
  gstatic.com is a cookieless domain. The persistent push connection needed by FCM (like APNS on iPhones) can tie the IP to a specific account, so this captive portal check gives them less information than they already have. Luckily on Android, you can use UnifiedPush and run your own push server to gain actual privacy.

kevincox 3y ago

> bc it benefits Google I doubt this is the reason. It seems more likely that no one has bothered to fix it. I agree that captive portals are a big hack with poor UX. This auto-detection does mitigate it but it is still very annoying especially if you have secure setups like encrypted DNS so the basic hijacking doesn't work properly.

Pxtl 3y ago

I find NeverSSL.com is a short, easy-to-remember URL for "oh crap am I in a captive portal or not".

_rdvw 3y ago

AOSP actually has handling when it detects a SIM MCC matching China: https://cs.android.com/android/platform/superproject/+/main:packages/modules/NetworkStack/res/values-mcc460/config.xml;l=1 https://cs.android.com/android/platform/superproject/+/main:...