From owner-freebsd-bugs@FreeBSD.ORG Sun Jul 22 19:30:09 2007 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 696D416A419 for ; Sun, 22 Jul 2007 19:30:09 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 449DB13C467 for ; Sun, 22 Jul 2007 19:30:09 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.14.1/8.14.1) with ESMTP id l6MJU8mF072016 for ; Sun, 22 Jul 2007 19:30:08 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.1/8.14.1/Submit) id l6MJU8rX072015; Sun, 22 Jul 2007 19:30:08 GMT (envelope-from gnats) Date: Sun, 22 Jul 2007 19:30:08 GMT Message-Id: <200707221930.l6MJU8rX072015@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Dan Lukes Cc: Subject: Re: bin/111493: routed doesn't use multicasts for RIPv2 via P2P interfaces X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Dan Lukes List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Jul 2007 19:30:09 -0000 The following reply was made to PR bin/111493; it has been noted by GNATS. From: Dan Lukes To: Vernon Schryver Cc: freebsd-gnats-submit@FreeBSD.org, bms@incunabulum.net, carlson@workingcode.com Subject: Re: bin/111493: routed doesn't use multicasts for RIPv2 via P2P interfaces Date: Sun, 22 Jul 2007 21:24:57 +0200 Vernon Schryver napsal/wrote, On 07/21/07 15:45: > If an interface is point-to-point (it sets the IFF_POINTOPOINT bit), > is it right to send to the RIPv2 multicast address? Why not ? To send or not to send the multicast is question related to "is supported or is not supported multicasting on interface". It isn't related to question "is the interface of type X". > Even on a GRE tunnel, why isn't it better to unicast to the router at > the other end of the tunnel instead of multicasting? 'it is better' and 'it is right' is questions of wo different categories. The answer for the first is "yes, there is no reason to forbid multicast addresses on P2P interface when if network stack support it". There is no reason to punish GRE users even if we don't like the protocol personally. The answer for the second is not simple. "Better" is subjective category - I don't know the all details of all network specifications of all networks. If you trust the administrator to decide on ethernet interface, I see no reason not to trust them on P2P interface as well. > Consider the error of the missing () in the first change: > + if (ifp->int_if_flags & IFF_POINTOPOINT && ! ifp->int_if_flags & IFF_MULTICAST) { You are true. > description of the failure with the current code. The descripion "of the failuter" is simple. The administrator of other side use not FreeBSD nor your routed. It's policy is - RIPv2 on multicasts. The RIPv2 on unicasts are blocked by firewall. He says that RIPv2 daemon on multicast link shall be able to use multicast, unless it's implementation is incomplete. I don't want dispute about it's mad policy decision. I dislike the GRE tunnels as you. Despite of it, there is no technical reason not to allow RIPv2 multicasting over a multicast capable interface, so the statement about incomplete implementation seems to be true. The required changes in the current code is simple, but the final decision is yours. Please note my knowledge of english language is far from perfect. Dan