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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

#651

Post by colanderman »

withinboredom wrote: post #601
colanderman wrote: post #589

Earlier quoted context omitted.

Yes so that is the hub case (2nd half of my comment) -- clients will RST each others' connections then. Unless you are MAC cloning but not IP cloning.

A computer doesn’t send a RST when it gets an unknown packet…

Yes, it does, that is the purpose of RST [1]:

> As a general rule, reset (RST) is sent whenever a segment arrives that apparently is not intended for the current connection. A reset must not be sent if it is not clear that this is the case. There are three groups of states:

> 1. If the connection does not exist (CLOSED), then a reset is sent in response to any incoming segment except another reset. A SYN segment that does not match an existing connection is rejected by this means.

It's possible for a node to be configured not to do this, but this is the default behavior.

[1] https://www.ietf.org/rfc/rfc9293.html#name-reset-generation

Re: WiFi without internet on a Southwest flight

#652

Post by angry_octet »

colanderman wrote: post #399
angry_octet wrote: post #376

Earlier quoted context omitted.

That greatly depends on whether the medium is broadcast (like a radio) or broadcast-like (a shared copper wire) and if it has CSMA/CD logic. Many of the replies are losing that detail and thinking of how it would effect a 1000base-T network, which maps MAC addresses to specific ports. For a broadcast network, the answer could be 'nothing' in the sense that both receivers would get the same traffic. The IP stack would…

Can't this often result in the two machines RSTing each others' TCP connections, depending on firewall settings?

Great question. It could, but there is a strong chance that the true recipient has already partially or fully ACKd the segment, thereby changing the sequence number and preventing a reset.

Re: WiFi without internet on a Southwest flight

#653

Post by phyzome »

duckqlz wrote: post #579
pak9rabid wrote: post #285

Earlier quoted context omitted.

lol, I used to do this all the time at non-free wifi hotspot locations, only I'd start off with a ping sweep of the entire subnet (nmap -sP) in order to get my ARP cache filled with a bunch of potential usable IP/mac addresses on the network. From there, I'd iterate through each one and set the IP & mac address until I found one that would let me through the firewall. Granted, being a NOC engineer at Wayport (now AT&…

If any lawyers or FAA employees are reading this I’m genuinely interested in what, if any, legal implications there would be for running nmap mid flight on an airline. Surely once you have spoofed the MAC address and IP of another passenger to gain unauthorized access to the planes LAN you have committed a crime but what about passively scanning?

nmap is not a "passive scan". You might be thinking of packet capture?

Re: WiFi without internet on a Southwest flight

#654

Post by phyzome »

spixy wrote: post #473
GuB-42 wrote: post #432

Earlier quoted context omitted.

I have read somewhere that so much precision could actually be dangerous in some circumstances. This is because this way, if a pilot goes 3000 ft for instance, it will be exactly 3000 ft, if another pilot also wants to go 3000 ft on a collision trajectory, it will be a guaranteed collision. When altitudes are not that accurate, there is a higher chance it being just a near miss. The solution, I think, was to simply a…

how is it any better when 2 opposite planes choose same 2950ft?

I vaguely recall that planes flying in different directions are assigned different altitude buckets.

Re: WiFi without internet on a Southwest flight

#655

Post by astura »

chankstein38 wrote: post #312
kxrm wrote: post #265

Earlier quoted context omitted.

A few years ago I was on a Southwest flight and had OpenVPN running because I forgot to turn it off. I was able to access the Internet through my tunnel without paying for access. I guess at the time they were only port blocking common ports (80, 443, 53 etc) if you didn't pay. They have since closed that hole.

For this same reason you used to be able to send messages via platforms like whatsapp without internet as well! I don't remember the airline I just remember I hadn't paid for internet but I could message and do a few other things but I couldn't browse the internet.

That's an advertised feature on some airlines.

Re: WiFi without internet on a Southwest flight

#656

Post by lr4444lr »

wannacboatmovie wrote: post #638
hk1337 wrote: post #179

Earlier quoted context omitted.

Someone will probably figure out how to send a request to disable auto-pilot or turn off the fasten seat belt sign.

Is this the thread where the web developers speculate wildly without facts or evidence and pretend to know more about airplanes than the aerospace engineers who built it?

Maybe it would help if Boeing 737's crash wasn't making the case for such incompetence.

Re: WiFi without internet on a Southwest flight

#657

Post by aselvan »

pak9rabid wrote: post #285
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…

lol, I used to do this all the time at non-free wifi hotspot locations, only I'd start off with a ping sweep of the entire subnet (nmap -sP) in order to get my ARP cache filled with a bunch of potential usable IP/mac addresses on the network. From there, I'd iterate through each one and set the IP & mac address until I found one that would let me through the firewall. Granted, being a NOC engineer at Wayport (now AT&…

I wrote this script to do exactly that a while back :)

https://github.com/aselvan/scripts/blob/master/macos/free_wi...

Re: WiFi without internet on a Southwest flight

#658

Post by mistymountains »

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…

You gave your 9 year old a smartphone?

Re: WiFi without internet on a Southwest flight

#659

Post by HouseOfStairs »

thedanbob wrote: post #317
chankstein38 wrote: post #312

Earlier quoted context omitted.

For this same reason you used to be able to send messages via platforms like whatsapp without internet as well! I don't remember the airline I just remember I hadn't paid for internet but I could message and do a few other things but I couldn't browse the internet.

That was probably deliberate. I flew United recently and they advertised free wifi for certain messaging apps, or you could pay to access more apps or the general internet.

I had a mosh connection open before I got on my last United flight and was able to use it the whole time. Seemed to me the free messaging/inflight entertainment tier doesn't block arbitrary UDP packets at all.

Re: WiFi without internet on a Southwest flight

#660

Post by glitchcrab »

noduerme wrote: post #549
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…

Wait, they like, opened up a private local IP on every plane for some guy who paid for a certain dedicated one?!

No, the IP is just that of a random paying user on that particular flight.
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