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#1 mac addresses...again

Posted: Wed Jul 28, 2021 11:04 am
by ed
some may recall, if I'm lucky, that I had a problem last September whereby I was trying to get the wifi adapter in Seb's machine to lock it's mac address. This was necessary in order to tell the router which machine to apply the parental controls to.
If the machine boots up with a different mac address on the wifi card each time then it's impossible for the router to apply parental controls.....

after much hair pulling and web searching I finally found a fix...
https://www.audio-talk.co.uk/phpBB3/vie ... 32#p180232

well...move on nearly 12 months and the boy is now running a dual boot and every time he boots to linux the m/c uses a different mac address....

anybody got any idea how to lock the mac address on the wifi card under linux??

I'm not entirely sure that he didn't know this might be a loophole in the parental control malarky...I'm doomed...I'm such an infrequent user these days that it's much worse than knowing absolutely nothing about IT.

#2 Re: mac addresses...again

Posted: Wed Jul 28, 2021 11:30 am
by Nick
If he is running Linux, then effectively he can get around anything you do by using a VPN or Tor.

Its none of my business, but maybe its time for a conversation instead of trying to close the barn door?

#3 Re: mac addresses...again

Posted: Wed Jul 28, 2021 11:45 am
by ed
I'm intrigued....
how can tor circumvent the router cutting the connection?
in regard to the conversation.....there are issues....I'm willing to take advice offline.....

#4 Re: mac addresses...again

Posted: Wed Jul 28, 2021 12:04 pm
by Nick
ed wrote: Wed Jul 28, 2021 11:45 am I'm intrigued....
how can tor circumvent the router cutting the connection?
in regard to the conversation.....there are issues....I'm willing to take advice offline.....
Well. what restrictions were you placing on the router that prevented stuff before? Give that I will see if I can think of a way around it. Or were you just blocking the mac address from sending any packets on the lan outside given times? Simple way around that would be to create a new mac address.

AS for the second part, I don't have that much to offer, all I did with mine was have the "don't be stupid and if you want ask" conversation. Between the three of them they seem to have ended up net savvy more by interactions with their peers than us.

#5 Re: mac addresses...again

Posted: Wed Jul 28, 2021 12:05 pm
by Nick
Oh, and also check if there are any other wifi networks that may be available.

#6 Re: mac addresses...again

Posted: Wed Jul 28, 2021 1:19 pm
by ed
the linksys router offers the following in parental control:

select the client from the map(router identifies by the mac address, assuming it won't change):
map.jpg
map.jpg (75.58 KiB) Viewed 4963 times
select restrict specific times from the choice page:
pcontrol.jpg
pcontrol.jpg (65.78 KiB) Viewed 4963 times
select times to cut the client device access to the wan:
edit-pc.jpg
edit-pc.jpg (50.26 KiB) Viewed 4963 times
if the device reboots with a different mac address it is invisible to the parental control
Or were you just blocking the mac address from sending any packets on the lan outside given times? Simple way around that would be to create a new mac address.
exactly so!...but he can't do that.

#7 Re: mac addresses...again

Posted: Wed Jul 28, 2021 1:40 pm
by ed
Nick wrote: Wed Jul 28, 2021 12:04 pm AS for the second part, I don't have that much to offer, all I did with mine was have the "don't be stupid and if you want ask" conversation.

yep, worked a treat for my previous 4 offspring.

#8 Re: mac addresses...again

Posted: Wed Jul 28, 2021 1:49 pm
by Nick
Well of he has the ability to dual boot then he can certainly change the MAC address.

#9 Re: mac addresses...again

Posted: Wed Jul 28, 2021 2:05 pm
by ed
Nick wrote: Wed Jul 28, 2021 1:49 pm Well of he has the ability to dual boot then he can certainly change the MAC address.
well that really comes back to my first post and the question..how?????

If it's as arcane as the windows method then it'll be a few years before he finds that.

#10 Re: mac addresses...again

Posted: Wed Jul 28, 2021 3:03 pm
by ed
ok...thanks for the effort, I think you're correct in pointing out that he may well find the method for setting a new mac address....
It didn't take much googling: macchanger or ip link...
I will set it for the time being, and see how long it takes him to twig...

I'm deffo losing it, I should have realised it would be far easier than the cobblers for windows.

#11 Re: mac addresses...again

Posted: Wed Jul 28, 2021 5:09 pm
by Nick
You can get a Linux distro that boots from a usb key so that's simple enough.

#12 Re: mac addresses...again

Posted: Wed Jul 28, 2021 5:12 pm
by rowuk
The answer is simple: White list instead of blacklist. Only allow your devices with their fixed MAC addresses. Everything else is blocked regardless if VPN or TOR. There is no easy way around except to steal your credentials...

#13 Re: mac addresses...again

Posted: Wed Jul 28, 2021 5:32 pm
by ed
rowuk wrote: Wed Jul 28, 2021 5:12 pm The answer is simple: White list instead of blacklist. Only allow your devices with their fixed MAC addresses. Everything else is blocked regardless if VPN or TOR. There is no easy way around except to steal your credentials...
yes rowuk, but that's the answer to a different question...

#14 Re: mac addresses...again

Posted: Wed Jul 28, 2021 5:48 pm
by Nick
There is no easy way around except to steal your credentials
Wireshark to find the mac address of a interface that is allowed through, then use that address when its not being used.

#15 Re: mac addresses...again

Posted: Wed Jul 28, 2021 6:02 pm
by ed
many thanks chaps.....I found the answer to my question at post 10...

the rest is way beyond my pay grade.

just to recap:
I need to fix the mac address in his pc so that I can set the parental controls in the router.
At the moment he plays games and doesn't know anything about mac addresses....when he does finally get round to such things I will cross the bridge. It may be a while, in which case I get a bit of rest from worrying about such things.