From owner-freebsd-net Sat Nov 2 23:20:20 2002 Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8290537B401 for ; Sat, 2 Nov 2002 23:20:19 -0800 (PST) Received: from InterJet.elischer.org (12-232-206-8.client.attbi.com [12.232.206.8]) by mx1.FreeBSD.org (Postfix) with ESMTP id EEFD643E97 for ; Sat, 2 Nov 2002 23:20:18 -0800 (PST) (envelope-from julian@elischer.org) Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id XAA55315; Sat, 2 Nov 2002 23:15:44 -0800 (PST) Date: Sat, 2 Nov 2002 23:15:43 -0800 (PST) From: Julian Elischer To: Pawel Tyll Cc: brian@awfulhak.org, net@freebsd.org Subject: Re: PPPoEd Bug. In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Sun, 3 Nov 2002, Pawel Tyll wrote: > Hi Brian, > > Today, after few hours of fighting with FreeBSD, I found one nasty bug in > your PPPoEd implementation. It all started with accidental patching of > RASPPPoE windows PPPoE client (http://user.cs.tu-berlin.de/~normanb/). > > There is a patch for RASPPPoE, which allows it to connect to non-RFC > compliant PPPoE servers, like 3Com modems. PPPoEd supports such clients, > however - after processing request from such client, it doesn't talk to > normal RFC-compliant clients anymore :( The code for doing non complient pppoe was written to be used as a client. I'm amazed it works as a server too.. (and I wrote it). Am I right in understanding that you accidentally had a non-compliant client, and therefore discoverd that FreeBSD as a server could cope with that, but that once it did, it couldn't go back? > - it looks like a quite nice DoS > attack possibility for me, ISP, lots of RFC-compliant users, and one > kiddie with patched RASPPPoE...Patched clients can connect without > problems, PPPoE receives requests from normal clients, however it > (probably - didn't check it) answers them with modified ether-type, > which makes it impossible for them to 'hear' the answer. Hope you can > come up with a fix soon :) > I'll have a look. > Best regards, > > Pawel 'ofca' Tyll. > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-net" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message