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WiFi without internet on a Southwest flight

jamesbvaughan.com

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Re: WiFi without internet on a Southwest flight

#271

Post by AdamJacobMuller »

savrajsingh wrote: post #219
KMnO4 wrote: post #214

Earlier quoted context omitted.

I used to do the same thing at hotels. Still often works. nmap -sn 192.168.0.1-255 To find everyone on the network, then start spoofing each of their MACs until you find one that works

I should probably know the answer, but what happens when two devices have the same MAC address?

"it depends, nothing good"

Network devices forward (switch, more technically) packets to and end device based on an internal MAC table (send packets for DE:AD:BE:EF to interface ge-0/0/0.0) and most devices populate their MAC table simply by looking at input packets and sending the "next" packet for that MAC address out the "last" received interface.

If two devices in a network have the same MAC address, they will effectively "fight" for control of the packet flow. You can win that fight by sending a lot of packets.

In practice, the other person is going to get annoyed and give up.

There are lots of technology which avoid this issue now, but the two primary ones are 802.1x (used in corporate/government environments) and DHCP snooping which can be much more broadly deployed. 802.1x is very complicated and I won't go into it, but, DHCP snooping works by limiting L2 forwarding (MAC table population) to only what the DHCP server says the end device should have and it does this just by inspecting the DHCP replies (no custom protocol) with some vendor specific extensions on the DHCP server side for complex scenarios (you can even do things like put ports in a specific VLAN based on the DHCP reply).

This works fine on a physical layer and most hotels are probably using something similar now (less for malicious abusive reasons, though that's a thing) but also just to work around poorly behaving devices and to reduce customer complaints. If you care (and have a modest amount of money) MAC and IP spoofing are dead on the physical layer.

For the wifi layer, very similar stuff exists in high-end gear (Rukus/Cisco) and is starting to trickle down to prosumer level gear like unifi. If you care (and have serious cash for Rukus) MAC and IP spoofing are also dead on the wifi layer.

Re: WiFi without internet on a Southwest flight

#272

Post by spmurrayzzz »

savrajsingh wrote: post #219
KMnO4 wrote: post #214

Earlier quoted context omitted.

I used to do the same thing at hotels. Still often works. nmap -sn 192.168.0.1-255 To find everyone on the network, then start spoofing each of their MACs until you find one that works

I should probably know the answer, but what happens when two devices have the same MAC address?

It more or less turns into an ARP cache race, only one device is gonna win. You can do some tricks with gratuitous ARPs as well for "dumber" networks, but more sophisticated setups usually have some broadcast ARP filters that are tied to an auth layer (radius, 802.1x. etc) and will drop broadcast frames from un-authed hosts.

Re: WiFi without internet on a Southwest flight

#273

Post by system2 »

sswaner wrote: post #109

On many United flights you can connect to onboard wifi without buying the plan and have internet access on port 22 and apparently unrestricted UDP. This allows me to connect to an EC2 instance running mosh. Coding in vim is a great way to pass the time on a flight.

Can't you create an SSH tunnel to a machine and RDP with it? Then you'd have fully functioning internet.

Re: WiFi without internet on a Southwest flight

#274

Post by ahoka »

commandlinefan wrote: post #246
savrajsingh wrote: post #219

Earlier quoted context omitted.

I should probably know the answer, but what happens when two devices have the same MAC address?

No way to tell for sure, but I can only assume that he had actually hijacked somebody else's connection and the other person's device stopped working for them. I sure wasn't going to stand up and ask the plane if anybody had had their internet plan hacked...

That’s not how it works, but probably made someones browsing experience worse.

Re: WiFi without internet on a Southwest flight

#275

Post by hackmiester »

remram wrote: post #159
hackmiester wrote: post #87

Here is how to get the equivalent data on a Delta flight. $ curl https://wifi.delta.com/api/flight-data | jq % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 448 100 448 0 0 5600 0 --:--:-- --:--:-- --:--:-- 5743 { "timestamp": "2023-07-11T14:54:41Z", "eta": "17:48", "flightDuration": 278, "flightNumber": "DAL786", "latitude": 39.723472595214844, "longitude": -97…

You can use jq's string interpolation feature to simplify this: $ curl -s https://wifi.delta.com/api/flight-data | jq -r '"https://maps.google.com/?q=\(.latitude),\(.longitude)"'

Thanks! I was trying to figure this out but I didn't have great Internet access (for some reason...) so I just hacked it instead.

Re: WiFi without internet on a Southwest flight

#276

Post by louison11 »

KMnO4 wrote: post #214
commandlinefan wrote: post #205

When my son was younger - maybe 9 or 10 or so, we were on a plane and he was using his phone and I looked over his shoulder and realized he was on the internet... but I hadn't paid for an internet plan. I said, "son, how are you using the internet?" He said, "oh, a kid at school showed me - if you go here" (he opened up the wifi settings where the DHCP assigned IP address is) "and start changing the numbers, eventual…

I used to do the same thing at hotels. Still often works. nmap -sn 192.168.0.1-255 To find everyone on the network, then start spoofing each of their MACs until you find one that works

This is what I did about 7-8 years ago on flights when I was still a reckless teenager. Would just wait for people to buy the plan, then spoof their Mac address. There was also a specific airline, although I can't remember which one, which let me in for free without MAC spoofing - by using a Google Cloud VPN I had previously set up. The paywall was essentially blocking all IP ranges except for Google servers for Google Analytics.

Re: WiFi without internet on a Southwest flight

#278

Post by s3p »

constantly wrote: post #211
catiopatio wrote: post #181

Earlier quoted context omitted.

Slack/Discord/Teams ? Those are desktop web applications hosted via Electron. Failing to leverage basic platform functionality is practically their telos. It’s a trivial, documented, supported, long-standing API for a common use-case. It is widely used, as documented, for its intended purpose. I cannot share information about specific applications.

No one is asking for a survey of apps that do this. You’re making the claim that it’s far from rare, so you have enough knowledge to make this claim. Share with us the smallest piece of your knowledge by naming one single other app that does this. It’s the least you can do since you’re making the claim. Please, I’m very curious!

I'm curious as well.

Re: WiFi without internet on a Southwest flight

#279

Post by ahoka »

system2 wrote: post #253
lupire wrote: post #223

Earlier quoted context omitted.

Does that work if both of you are trying to send/receive packets at the same time?

WiFi signal is received by both. Packages are ignored if they are not requested by either one of the systems. You can also receive anyone else's packages while you are using your internet but ignoring the ones you don't need. (If interested try aircrack-ng.)

Only if it’s unencrypted, of course. Rarely the case nowadays.

Re: WiFi without internet on a Southwest flight

#280

Post by pantalaimon »

KMnO4 wrote: post #214
commandlinefan wrote: post #205

When my son was younger - maybe 9 or 10 or so, we were on a plane and he was using his phone and I looked over his shoulder and realized he was on the internet... but I hadn't paid for an internet plan. I said, "son, how are you using the internet?" He said, "oh, a kid at school showed me - if you go here" (he opened up the wifi settings where the DHCP assigned IP address is) "and start changing the numbers, eventual…

I used to do the same thing at hotels. Still often works. nmap -sn 192.168.0.1-255 To find everyone on the network, then start spoofing each of their MACs until you find one that works

I’ve never been at a hotel that charged for WiFi - is that a US thing?
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