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zorprime
09-13-2003, 08:38 PM
I am going to try my hand at contributing some code. I would like to try to tackle the PPPoE decode if it hasn't been done yet (I haven't seen any other mention of it here in the forums so I am assuming it hasn't).

I don't know beans about unix network programming but I figure all the coding I've done in school now shouldn't make this too much of an obstacle.

I'm starting my journey with RFC 2516 and packet.cpp in front of me, after all the laughter subsides if anyone could point me to a better starting spot I'm all ears :p

Thanks

Zorprime

ksmith
09-14-2003, 08:41 PM
I'm not sure I see the point of that.

zorprime
09-14-2003, 09:04 PM
Well true hubs have become a rarity... so then there are 2 choices: Have a linux box login PPPoE to your DSL modem or use same linux box to bridge between router and modem and catch the packets as they come through (which would be the PPPoE packets)

off topic but related: If I can get my hands on a linksys G router/AP I'd like to see if showeq would compile on it and try doing X forwarding... that would rock.

zorprime

junk
09-15-2003, 04:28 AM
But it already works if your linux box bridges your router and your modem (i.e. is your gateway). Or did I misunderstand?

S_B_R
09-15-2003, 08:12 AM
By his description I'm guessing he doesn't have his router setup to do PPPoE so he's doing it with his client machine... Since Most "Broadband Routers" do infact support PPPoE the traffic coming out of the private side ports should be Ethernet, if configured propperly.

Secondly, if your linux box is doing PPPoE attached to your DSL(or whatever) then simply sniffing the private interface for the private IP address of you EQ Client machine would be successful. Since again the Packets coming out of the private side interface should be standard Ethernet.

zorprime
09-15-2003, 09:00 PM
Originally posted by S_B_R
By his description I'm guessing he doesn't have his router setup to do PPPoE so he's doing it with his client machine... Since Most "Broadband Routers" do infact support PPPoE the traffic coming out of the private side ports should be Ethernet, if configured propperly.

Secondly, if your linux box is doing PPPoE attached to your DSL(or whatever) then simply sniffing the private interface for the private IP address of you EQ Client machine would be successful. Since again the Packets coming out of the private side interface should be standard Ethernet.

My router is setup to do PPPoE but since all the dsl/cable routers I know of are all switches then attaching a showeq box to another port won't do any good.

I remember a thread a while back that hinted that PPPoE decoding might be useful... I guess that has changed. The only use personally I see it having right now is that my roommate and I have multiple accounts. So have a linux box sitting at the modem and sniff all streams there and use X forwarding to a couple of other boxes.

fester
09-16-2003, 05:18 AM
I believe this is a waste of time.

Place a linux machine between the Cable/DSL modem and your LAN and have the linux machine do PPPoE to the modem and run ShowEQ on the connection to your LAN.

Both of you use one account and cancel the other PPPoE account (you don't need two.)

S_B_R
09-16-2003, 08:10 AM
Originally posted by zorprime
My router is setup to do PPPoE but since all the dsl/cable routers I know of are all switches then attaching a showeq box to another port won't do any good.

I remember a thread a while back that hinted that PPPoE decoding might be useful... I guess that has changed. The only use personally I see it having right now is that my roommate and I have multiple accounts. So have a linux box sitting at the modem and sniff all streams there and use X forwarding to a couple of other boxes.
Your Idea which require SEQ to decode PPPoE

DSL Modem
|
Hub-------SEQ
|
BroadbandRouter w/PPPoE
| |
EQClient1 EQClient2
My idea which doesn't require SEQ to decode PPPoE

DSL Modem
|
BroadbandRouter w/PPPoE
|
------Hub-------
| | |
EQClient1 | EQClient2
SEQ

Or here's a 3rd option, and in my opinion the best method.

DSL Modem
|
Linux Box
(Doing PPPoE,NAT, and SEQ)
|
------Hub-------
| |
EQClient1 EQClient2

zorprime
09-16-2003, 03:44 PM
To fester's reply --- we do have one PPPoE account - I'm talking multiple EQ accounts

S_B_R: Yes option 3 is best, but again it seems that hubs have all but disappeared.

Since this is getting off topic of development... if anyone wants PPPoE decoding as a possible feature raise your hand - otherwise we can lock this thread and call it a day.

Ciao

zorprime

S_B_R
09-16-2003, 03:56 PM
The thing is, inorder for you SEQ box to see the PPPoE packets it's either going to have to be on a hub connected to the DSL Modem Directly connected to the DSL Modem.so you see in either case there would be an option to not use PPPoE. in option "A" you need a true hub, in option "B" you almost have a NAT situation anyway.

That was my only point.

I think what changed is now Linux can be used to authenticate PPPoE... maybe? Anyway more developers working on SEQ is always a good thing in my book ;)

--EDIT--
Oh btw option 3 from my other post, does not require a hub (or even promiscuous mode). All the packets are passing through you linux box, so it has ready access to the EQ stream.

Mr. Suspicious
09-16-2003, 04:11 PM
S_B_R's option number 3 will also work if you replace the HUB in the schematic with a Switch.