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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 79BCEC433E1 for ; Wed, 26 Aug 2020 01:50:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 530AF206E3 for ; Wed, 26 Aug 2020 01:50:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="OR7jYTnn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726766AbgHZBt5 (ORCPT ); Tue, 25 Aug 2020 21:49:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726772AbgHZBtx (ORCPT ); Tue, 25 Aug 2020 21:49:53 -0400 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87451C061757 for ; Tue, 25 Aug 2020 18:49:52 -0700 (PDT) Received: by mail-wm1-x342.google.com with SMTP id x5so204904wmi.2 for ; Tue, 25 Aug 2020 18:49:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=googlenew; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FSqpiVb2VHbicFs91NoR7CGMW6s7gPW0OnsX8hYxTdk=; b=OR7jYTnnl/7sfX3AWTgCn4ixomtkfiZbj9dmPl59jLvYB4wAxvvAQYP9KwBCCr0PZk jhYD8aHRPiVu/DvukwWmIbdCMZqLYcIkdS+nS5kfsoH/bNkhV2MoWoATWWK9VJG3DgRP vQE6g3IBDMOdgAXtgs+LUzJocokrARZoJOPkh9iZDZKXc4Ajo+F984BG34yLGmoLwXtr lVLW36hRIx5lgf3awKaV90QtJi+o8gImOq4Hfnw+G4557klA7+MibaQU0k506N4D/nSU RLYWeBerdZs8aRymiT32FFpDrmATQCszSfD0t7SImQc+/1hIg28l4HkChBzjGSZkCJYV c8EA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FSqpiVb2VHbicFs91NoR7CGMW6s7gPW0OnsX8hYxTdk=; b=A2+j/vqBhhHfOp3zV97LSz3cBk19V3qG2rHRwyWutvbnzcRocNNRmpp46i2E6rETKW V0FH0IYXf5LANNMmVqxwlrgCaxSK2yt6TXHN8kYn9RW8mYWdOgQ42Yfpgh5etTo+uXuS yHe3StEcdSxReHLOgQAiZ7SYBOBnmIVq0uew9uLkAd4BgTsZLlbXUeSmdZWLyfVKC/l6 k2Gz+GGleeuX4YmvNSZWrCC45NzY5Enj4RA/SWVSzc+vTZoeOGYHfvLm/bSQPudYJo/p zwHvtoaV6sbWYe35Ajfye0u4AiHIoT0fMBmEpYr3vULY4ESCEfpkgTz/JULy3+7rZnxJ XS9A== X-Gm-Message-State: AOAM530IRWhojKqNlC7Ow50b3oz4BCllkWYTg/UTe4ovVWnaHblhymOb GIhBmXhh7lTSIuWZ5ElfVKT6oAXZ5V/V4aiyGIc= X-Google-Smtp-Source: ABdhPJwNMNkrni4rBF7mJl0ZgMtnGn8jDQ5Kr9MAaUf7fQSiMZ34ZwUojW/wTvT0Oe3KXMiZbzqt9w== X-Received: by 2002:a7b:cc95:: with SMTP id p21mr4321648wma.167.1598406590787; Tue, 25 Aug 2020 18:49:50 -0700 (PDT) Received: from localhost.localdomain ([2a02:8084:e84:2480:228:f8ff:fe6f:83a8]) by smtp.gmail.com with ESMTPSA id c10sm1263661wmk.30.2020.08.25.18.49.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2020 18:49:50 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Dmitry Safonov , "David S. Miller" , Florian Westphal , Herbert Xu , Jakub Kicinski , Steffen Klassert , Stephen Suryaputra , netdev@vger.kernel.org, Johannes Berg , Shuah Khan , linux-kselftest@vger.kernel.org Subject: [PATCH v2 0/6] xfrm: Add compat layer Date: Wed, 26 Aug 2020 02:49:43 +0100 Message-Id: <20200826014949.644441-1-dima@arista.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changes since v1: - reworked patches set to use translator - separated the compat layer into xfrm_compat.c, compiled under XFRM_USER_COMPAT config - 32-bit messages now being sent in frag_list (like wext-core does) - instead of __packed add compat_u64 members in compat structures - selftest reworked to kselftest lib API - added netlink dump testing to the selftest XFRM is disabled for compatible users because of the UABI difference. The difference is in structures paddings and in the result the size of netlink messages differ. Possibility for compatible application to manage xfrm tunnels was disabled by: the commmit 19d7df69fdb2 ("xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems") and the commit 74005991b78a ("xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host"). This is my second attempt to resolve the xfrm/compat problem by adding the 64=>32 and 32=>64 bit translators those non-visibly to a user provide translation between compatible user and kernel. Previous attempt was to interrupt the message ABI according to a syscall by xfrm_user, which resulted in over-complicated code [1]. Florian Westphal provided the idea of translator and some draft patches in the discussion. In these patches, his idea is reused and some of his initial code is also present. There were a couple of attempts to solve xfrm compat problem: https://lkml.org/lkml/2017/1/20/733 https://patchwork.ozlabs.org/patch/44600/ http://netdev.vger.kernel.narkive.com/2Gesykj6/patch-net-next-xfrm-correctly-parse-netlink-msg-from-32bits-ip-command-on-64bits-host All the discussions end in the conclusion that xfrm should have a full compatible layer to correctly work with 32-bit applications on 64-bit kernels: https://lkml.org/lkml/2017/1/23/413 https://patchwork.ozlabs.org/patch/433279/ In some recent lkml discussion, Linus said that it's worth to fix this problem and not giving people an excuse to stay on 32-bit kernel: https://lkml.org/lkml/2018/2/13/752 There is also an selftest for ipsec tunnels. It doesn't depend on any library and compat version can be easy build with: make CFLAGS=-m32 net/ipsec Patches as a .git branch: https://github.com/0x7f454c46/linux/tree/xfrm-compat-v2 [1]: https://lkml.kernel.org/r/20180726023144.31066-1-dima@arista.com Cc: "David S. Miller" Cc: Florian Westphal Cc: Herbert Xu Cc: Jakub Kicinski Cc: Steffen Klassert Cc: Stephen Suryaputra Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: netdev@vger.kernel.org Dmitry Safonov (6): xfrm/compat: Add 64=>32-bit messages translator xfrm/compat: Attach xfrm dumps to 64=>32 bit translator netlink/compat: Append NLMSG_DONE/extack to frag_list xfrm/compat: Add 32=>64-bit messages translator xfrm/compat: Translate 32-bit user_policy from sockptr selftest/net/xfrm: Add test for ipsec tunnel MAINTAINERS | 1 + include/net/xfrm.h | 32 + net/netlink/af_netlink.c | 48 +- net/xfrm/Kconfig | 11 + net/xfrm/Makefile | 1 + net/xfrm/xfrm_compat.c | 609 +++++++ net/xfrm/xfrm_state.c | 11 +- net/xfrm/xfrm_user.c | 79 +- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/ipsec.c | 2195 ++++++++++++++++++++++++ 11 files changed, 2953 insertions(+), 36 deletions(-) create mode 100644 net/xfrm/xfrm_compat.c create mode 100644 tools/testing/selftests/net/ipsec.c -- 2.27.0