[CentOS] RADIUS

Fri Mar 2 17:07:35 UTC 2018
hw <hw at gc-24.de>

Stephen John Smoogen wrote:
> On 1 March 2018 at 12:26, hw <hw at gc-24.de> wrote:
>> Stephen John Smoogen wrote:
>>>
>>> On 1 March 2018 at 08:42, hw <hw at gc-24.de> wrote:
>>>
>>>>
>>>> I didn´t say I want that, and I don´t know yet what I want.  A captive
>>>> portal may
>>>> be nice, but I haven´t found a way to set one up yet, and I don´t have an
>>>> access
>>>> point controller which would provide one, so I can´t tell if that´s the
>>>> right
>>>> solution.
>>>>
>>>
>>> This is the problem with this entire thread in a nutshell. You don't
>>> know what you want but what you have articulated at various points is
>>> that you do know what you want. You then state something that won't
>>> work because of some factor or another. People then correct you on
>>> that, and you then get hostile because you were just thinking out loud
>>> but no one knew that. Thinking out loud works ok in real life because
>>> we give special queues like looking abstractly or being able to say
>>> "Oh no I am just thinking out loud" right away. Instead in email none
>>> of that happens and people get more and more hostile and angry
>>> thinking the other side is trying to make them do completely opposite.
>>>
>>> Let us try starting over. You may have answered these in other places,
>>> but people need to see them in one place at one time versus trying to
>>> look through cache of other emails.
>>>
>>> What do you want?
>>
>>
>> I was asking for documentation telling me how RADIUS can be used, not only
>> that it can be used.
>>
>>> What are your constraints? [AKA what have you been told to do.]
>>
>>
>> The task is to provide wireless coverage for employees and customers on
>> company premises.  It is desirable to be able to keep track of customers,
>> as in knowing where exactly on the premises they currently are (within
>> like 3--5 feet, which is apparently tough), and simpler things like knowing
>> how long they stay and if they have been on the premises before.  To avoid
>> legal issues, it is probably advisable that customers need to agree to
>> some sort of terms of usage.
>>
> 
> Oh yeah. Who ever gave you those marching orders needs to talk with
> all kinds of lawyers... even researching for it might be problematic
> in some countries due to a multitude of laws. You are walking out of
> setting up a wireless environment into full-scale surveillance.

That´s not my problem to solve, but think about it:  You can get a lot more
information using CCTV cameras, and those are everywhere.  Unfortunately,
nobody cares, and it´s not like you have a choice.  So why would there
be any legal issues?

> That said, what you are looking for is not going to be accomplished
> with simple radius without a large amount of development. It is also
> going to need a lot of wireless sensors running at different
> frequencies through out the building. Most of that is done usually
> with special commercial hardware/software and falls outside of scope
> of this list by a mile.

RADIUS would only be a tool to use for authentication and perhaps accounting.
Figuring out where users are is an entirely different problem.

> RADIUS may be something that is done with all of this but only far way
> back in the chain of tools needed. It might be something that the
> specialized hardware, scanners, sensors, etc might tie into if they
> don't have their own specialized tool. Worrying about it before those
> are researched, etc is to use an English idiom: putting the cart
> before the horse.

I´m surprised that wireless access point controllers, by default, do not
use the strength of the signal received from a device by three or more access
points to simply triangulate the position of the device.  Of course, you
only get the positions of devices relative to access points, but once you
have that, you only need to use a map of the place that shows all the access
points and the positions of devices relative to them to figure out where
everyone is.

That´s a rather simple thing to do, isn´t it?  Some documentation of HPs MSRs
stated that the controller can distribute the wireless devices between access
points to even out the bandwidth, and if it can do that, it could as well
distribute them for triangulation.

>> It is desirable to be able to know where employees currently are, though
>> it doesn´t neeed to be as precise.
>>
>>> When do you need it?
>>
>>
>> There´s no given time frame; it´s as soon as possible and preferably
>> this year.
>>
>> It is necessary to (re-)do the entire network infrastructure before wireless
>> coverage can be achieved, one of the reasons being that it is currently
>> impossible to use VLANs all over the place.
>>
>>> What is the environment that it is to run in?
>>
>>
>> a shopping area
>>
>> Some of the wireless access points may need to take part in what is
>> apparently called a mesh to be able to supply remote parts of the premises.
>>
>>> What research have you done (with references)?
>>
>>
>> I searched for documenation about how to actually use RADIUS and didn´t
>> find any.  I´ve asked for pointers to such documentation here.
>> I´ve read the RADUIS admin guide.  I´ve done a test setup by installing
>> RADIUS and configuring a switch to use it to authenticate users logging
>> into the switch via ssh and found it works fine.  I have set up a couple
>> access points in a test setup which currently provide wireless access for
>> employees and wireless internet access for customers around some points
>> of the premises.  I found out what a captive portal is.
>>
>>> Then people will have a better ability to answer:
>>> What have others done to meet those needs?
>>> How have they implemented it?
>>>
>>> Then ask
>>> What other things do you need for me to help?
>>>
>>> People can then ask questions about things you didn't fully explain.
>>> This is helpful because going from the previous emails your phrasing
>>> made it sound like you needed unknown people to not be able to get
>>> onto the network until they were authenticated, but authentication
>>> requires them to be on a network, but you can't allow them to be on
>>> any network until they are authenticated. That may not be what you
>>> mean (on the other hand, I have had that conundrum given to me at a
>>> job and we had to spend 3 months convincing the boss(es) that was
>>> impossible with the tools we had (and probably impossible without)).
>>
>>
>> That is what using RADIUS apparently leads to when you have devices using
>> PXE boot.  Maybe they need to be considered as a security risk and be
>> replaced.
>>
> 
> OK I think this is where we are also getting confusion. PXE booting is
> a multistep process to get a hardware device onto the network and
> running a provided kernel. It is also something which usually only
> works on wireless in controlled situations (aka magic).

Oh I never thought of using it for wireless devices.

> So people aren't sure why you are wanting to PXE boot something a
> customer would carry (aka a cell phone/tablet) since that does not PXE
> boot at all. You might be meaning DHCP instead but maybe you are
> meaning something else.

When there´s a RADIUS server on the network, not only wireless devices
could/should use it.

> So the normal tools are to set up different LANs for different access.
> On wired or wireless this is usually done with a dedicated network
> which only devices which a) have a proven mac, b) use WPA-Enterprise
> with radius to log in. For untrusted devices that might be looking for
> any open lan, you have an open net which has a captive portal which
> can 'kick' certain devices to a semi-trusted lan. [This is device
> dependent so don't expect it to work for everyone.] Then you have a
> semi-trusted lan which may have a guest password. It is still a
> captive portal so that people on it are only able to get out after
> they provided a second allowed password. The captive portals may be
> backed by Radius, but it will depend on what software they are using.
> 
> [The above comes from doing this a decade ago.. things have changed so
> please follow any new guidance/books on commercial wireless design.]

Well, I don´t want to trust MAC addresses because they can be faked.

>> Unauthenticated people are easier to handle because people can provide
>> credentials for authentication without PXE booting them first and do not
>> access the network without a device (unless they mess with the very network
>> hardware, using cables to create loops or accidentially cutting them or
>> unplugging them or whatever --- people do all kinds of things, with
>> authentication and without ...).
>>
>> Devices with network access are much more dangerous than unauthenticated
>> people because such devices could be used by such people to also gain
>> network
>> access, or they could try to have bad effects on the network.
>>
>> So everthing is dangerous, authenticated or not.
>>
> 
> Everything is always dangerous :). It is good to recognize that
> because a lot of times people just assume there is a magical
> non-dangerous way and then spend all their time trying to find it. The
> best we can do is find how to respond to the danger.

hm

Is sleeping dangerous?