From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9003 invoked by alias); 17 Jun 2005 11:30:34 -0000 Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Received: (qmail 8947 invoked by uid 22791); 17 Jun 2005 11:30:21 -0000 Received: from londo.lunn.ch (HELO londo.lunn.ch) (80.238.139.98) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Fri, 17 Jun 2005 11:30:21 +0000 Received: from lunn by londo.lunn.ch with local (Exim 3.36 #1 (Debian)) id 1DjF18-0001IV-00; Fri, 17 Jun 2005 13:28:10 +0200 Date: Fri, 17 Jun 2005 11:30:00 -0000 To: Sturle Mastberg Cc: Gary Thomas , eCos Discussion Message-ID: <20050617112810.GA4982@lunn.ch> Mail-Followup-To: Sturle Mastberg , Gary Thomas , eCos Discussion References: <42B28F30.1070905@tandberg.net> <1119002495.13965.224.camel@hermes> <42B2ACAD.5030608@tandberg.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42B2ACAD.5030608@tandberg.net> User-Agent: Mutt/1.5.9i From: Andrew Lunn Subject: Re: [ECOS] Possible fix for duplicated ARP entries in the FreeBSD stack X-SW-Source: 2005-06/txt/msg00136.txt.bz2 On Fri, Jun 17, 2005 at 12:57:49PM +0200, Sturle Mastberg wrote: > Gary Thomas wrote: > >On Fri, 2005-06-17 at 10:52 +0200, Sturle Mastberg wrote: > > > >>Hello, > >> > >>For some time I've had problem with duplicated ARP entries that have > >>caused all sorts of problems. I searched the archive and discovered that > >>the problem had been reported before: > >> > >> > >>http://sourceware.org/ml/ecos-discuss/2004-11/msg00097.html > >> > >> > >>My proposal to a fix is to make the sockaddr_inarp struct > >>(include/netinet/if_ether.h) equal in size to the sockaddr struct by > >>padding it at the end. This is exactly what is done to the sockaddr_in > >>struct (include/netinet/in.h) for different reasons. > >> > >> > >>I reached this conclusion after I discovered that two virutally > >>identical calls to rtalloc1 (net/route.c) returned different results. > >>The first instance appears in arplookup (netinet/if_ether.c) where the > >>first parameter to rtalloc1 is a struct sockaddr_inarp cast to a struct > >>sockaddr. The second instance appears in ip_output (netinet/ip_output) > >>via rtalloc_ign (net/route.c) where the first parameter to rtalloc1 is > >>an actual struct sockaddr. The rtalloc1 function does a radix tree > >>search with a call to the rn_match function (net/radix.c). A closer look > >>at this code reveals that it does indeed depend on the size of the > >>supplied struct. > >> > >> > >>The only conclusion a can draw from this is that the three structs: > >>sockaddr, sockaddr_in and sockaddr_inarp must all be of equal size. I > >>have checked the FreeBSD source repository that this is the case for the > >>original code. > >> > >> > >>While browsing the FreeBSD source repository I discovered that the > >>sa_data character array member of the sockaddr struct was increased in > >>size in the eCos FreeBSD stack. Does anyone know why this increase was > >>introduced in eCos? I beleave Nick did this for IPv6. This bigger size allows an IPv6 address to be placed into a sockaddr which you cannot normally do. Andrew -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss