From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B727C04AAC for ; Thu, 23 May 2019 03:42:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD8F22089E for ; Thu, 23 May 2019 03:42:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="B0gSmD7D" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728189AbfEWDmh (ORCPT ); Wed, 22 May 2019 23:42:37 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:33159 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726070AbfEWDmh (ORCPT ); Wed, 22 May 2019 23:42:37 -0400 Received: by mail-pf1-f194.google.com with SMTP id z28so2457466pfk.0 for ; Wed, 22 May 2019 20:42:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=mSz3HTfyv7+QQGumFbkOTWi87sl665Jw1P7icz4c5qc=; b=B0gSmD7DfhNwq+Bu4OhjHS7iGgdbEN9KUmDTqZ73nrP4mqV5ZP9xT+Wm6CWm7FYVN3 sMtn1MqGkvOm54vqBAhSVOHmUwl7RKu/oZ74Pm/jCUqbnmOsh4mXVhDBMwHpgYDGtnBQ T4UGWbKxaIfwwb8MdHSpF0KuKhxFWFqqvHLdg3yGgUooLJ6wkRuoB/c0nC7zZNQ4pBb2 +zPnSiNtJK2m5dEkxnb8POq7J2Hspj+gpyKRD1nlSB/2AQpJ3kNYvVAG/idpus2HsvHz tBnI8xQFNpbbbtozPt2uWLV+Ydf54WonVXz2lgA3l6sn09I1eG83OXFBHfnNLVg3gK1s 71dw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=mSz3HTfyv7+QQGumFbkOTWi87sl665Jw1P7icz4c5qc=; b=UIacfPF3RXf5TY0TCd6VqjW/VfkQP+s38e/QxZkGaLUDMyjLZdOL4p1X09T6Aj38u/ T1xwE2x1CC9Pbc2hJTLcIkFdO25aotzygI8Qum3hpYQOTHVpOFemLAt6evUIPNORBsel XPOfalvZCy29r/CR9tml0nYe5j90kYQZvj4y2OFAQ/aiScyDvDhUTcjHK1vTon6GAfyd 4FJBSxsrDNNb1UkPmIQsld91EMrrBraM3PKrGwVoSvQiEEEeXJirEtANsZr2G5OHPMRf dGVUrPJpAsIIhaxmOXwLgXNkBJzuWtLji848urSsL553oS93ynIBeLk5rluq7cl4MYVW dbpw== X-Gm-Message-State: APjAAAWF12VAcSyykzKWrfOEEdFCgQWId7MYjBNq2YoHx1A9rJkxfx0C W6aJM22d7ZyZG4ZNafPcDouh3HZJ X-Google-Smtp-Source: APXvYqzus9Pn4wjUdJonxk/g6Cgt5We7Ey2D6vSeT6FZdK+K1U1rNqnYIst0g0crfdP84idTrpheCA== X-Received: by 2002:a65:62cc:: with SMTP id m12mr39441938pgv.237.1558582956711; Wed, 22 May 2019 20:42:36 -0700 (PDT) Received: from ?IPv6:2601:282:800:fd80:f892:82c5:66c:c52c? ([2601:282:800:fd80:f892:82c5:66c:c52c]) by smtp.googlemail.com with ESMTPSA id a8sm17031277pfk.14.2019.05.22.20.42.34 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 22 May 2019 20:42:35 -0700 (PDT) Subject: Re: [PATCH iproute2] ip route: Set rtm_dst_len to 32 for all ip route get requests To: Stephen Hemminger , David Ahern Cc: netdev@vger.kernel.org, Jason@zx2c4.com References: <20190517175913.20629-1-dsahern@kernel.org> <20190522161652.42104430@xps13.lan> From: David Ahern Message-ID: <35f170ea-d051-3e76-bfa7-1a5259a1d5c8@gmail.com> Date: Wed, 22 May 2019 21:42:33 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190522161652.42104430@xps13.lan> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 5/22/19 5:16 PM, Stephen Hemminger wrote: > On Fri, 17 May 2019 10:59:13 -0700 > David Ahern wrote: > >> index 2b3dcc5dbd53..d980b86ffd42 100644 >> --- a/ip/iproute.c >> +++ b/ip/iproute.c >> @@ -2035,7 +2035,11 @@ static int iproute_get(int argc, char **argv) >> if (addr.bytelen) >> addattr_l(&req.n, sizeof(req), >> RTA_DST, &addr.data, addr.bytelen); >> - req.r.rtm_dst_len = addr.bitlen; >> + /* kernel ignores prefix length on 'route get' >> + * requests; to allow ip to work with strict mode >> + * but not break existing users, just set to 32 >> + */ >> + req.r.rtm_dst_len = 32; >> address_found = true; >> } >> argc--; argv++; > > Why not warn user that any prefix length (ie not 32) is ignored, > then do what you propose. > My first version did that. I thought people would complain about a stderr message. At least with failing the 'route get' scripts can be fixed. After more thought even changing the prefix length for users presents a limitation on future changes.