From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Woodhouse Subject: Re: vpnc-script fix for changed iproute output with newer kernels Date: Fri, 29 Jul 2011 22:26:36 +0100 Message-ID: <1311974797.20983.0.camel@i7.infradead.org> References: <20110728021227.GA3620@gmail.com> <20110728021853.GB3620@gmail.com> <1311942793.17528.57.camel@i7.infradead.org> <20110729.054649.1274733167127164255.davem@davemloft.net> <1311944244.17528.76.camel@i7.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: jsbronder@gentoo.org, netdev@vger.kernel.org, shemminger@vyatta.com To: David Miller Return-path: Received: from casper.infradead.org ([85.118.1.10]:51119 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752838Ab1G2V0m (ORCPT ); Fri, 29 Jul 2011 17:26:42 -0400 In-Reply-To: <1311944244.17528.76.camel@i7.infradead.org> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 2011-07-29 at 13:57 +0100, David Woodhouse wrote: > > You're going to have to be knowledgable about which attributes are > > part of the route, whether you want to do this with iproute2 as a tool > > or whether you do this directly with C code using netlink. > > I don't think I really want to try shipping vpnc-script with C code. > > The 'opt-in' approach seems like the best one for now, then. I suppose > we want just the 'via' and 'dev' and 'src' attributes... anything else? This should do it for now, I suppose: --- a/vpnc-script +++ b/vpnc-script @@ -139,8 +139,9 @@ destroy_tun_device() { if [ -n "$IPROUTE" ]; then fix_ip_get_output () { - sed 's/cache//;s/metric \?[0-9]\+ [0-9]\+//g;s/hoplimit [0-9]\+//g;s/ipid 0x....//g' + sed -e 's/ /\n/g' | \ + sed -ne '1p;/via/{N;p};/dev/{N;p};/src/{N;p};/mtu/{N;p}' } set_vpngateway_route() { $IPROUTE route add `$IPROUTE route get "$VPNGATEWAY" | fix_ip_get_output` I'm still not happy with it, since I'm not 100% convinced I'm preserving all the attributes that need to be preserved, and will need to be preserved in future. I managed to keep 'src', but what else might there be? I just don't want to have to know. On trying to torture-test it, I also noticed that 'ip route get' doesn't do what I'd want in the case of the following route: default src 90.155.92.214 nexthop via 81.2.98.173 dev eth1 weight 1 nexthop dev ppp1 weight 1 [root@solos ~]# ip route get 131.111.8.42 131.111.8.42 via 81.2.98.173 dev eth1 src 90.155.92.214 cache mtu 1500 advmss 1460 hoplimit 64 -- dwmw2