From patchwork Thu Jul 26 02:31:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 949435 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=arista.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=arista.com header.i=@arista.com header.b="hMmVlOjg"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 41bbjr4yy6z9s21 for ; Thu, 26 Jul 2018 12:33:04 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729144AbeGZDqc (ORCPT ); Wed, 25 Jul 2018 23:46:32 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:39191 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728975AbeGZDq3 (ORCPT ); Wed, 25 Jul 2018 23:46:29 -0400 Received: by mail-ed1-f68.google.com with SMTP id h4-v6so331518edi.6 for ; Wed, 25 Jul 2018 19:31:56 -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:in-reply-to:references; bh=KGoK3OMLZtNNtazxqMz9O1g2b/QG4N/rvtrmfVBaNKw=; b=hMmVlOjgu3cExAPljGXnFlQTIdhe78lf0XeL2+7TMs2vyPC0CLm9NDLe8hHRqzhPGK v5k5DzwZJ9afvV+2eWV4wfxAAW7q2LJ8p+kYm6aZOwVzxJtoeKeE5dgDoTVIsnfLGHSR ALvMPhlnF2U07EMdj/LD6BRnKx60Ajtz62Q6oWdxakQjMeRQoWqi2xap/HB0EVsDyjuX wL0JhXNgN6IZ0HzPEfuBObuMx0sqD8Wy+2e7BjbVkVN6HOFJcCNuUwFrG2Pm6Ey+zenX UPc0IeqrxthOdcy0eBd3xGvkvDNXhsX/ie+x/DG1eZJIJeWRJTDuLTZmcKtqoFO5zOpD iqKw== 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:in-reply-to :references; bh=KGoK3OMLZtNNtazxqMz9O1g2b/QG4N/rvtrmfVBaNKw=; b=HP+UL/TsLg+VUsI4VGAWdJsIoqYcvyPVOKK4q2wAEDH/Ytj0Pojxzc91ZcVeJFfQwX ghbUJLsbKPMioeyM+gCB2ibK+xb2S5L01i9dtVJtBZBhEjIkoVn1wLV6lE7iT9sBh9ra kPBdjhyW1VE0EmTwaAP5e9JEIT3mLD4LNbqkNNdDpn5A6apxfymyTMjzC+W4dBPewlCF dUG31fHSZzw0H6W7ffaz+df/2yKB/NneX1+Ytq1/Cs1RTyY66rtamK9cFZMxO8uEppsd MRQuxBxzObUVwps9H36oeBSf3uWHZSMUIGWDeQah4E7uXzGwioBVbn5/sNUCap04n54B m8kw== X-Gm-Message-State: AOUpUlE0dmhj+Y20tiFc9wu8gVxcR0GRivQtezD6Lbq8QBWAIP2peCRe 3T0SUFWHI8IgKEzfWvo5vE71RQ== X-Google-Smtp-Source: AAOMgpcCx3zX76fNkUdYYaZw3nPEC29UpNy9FQ4yDkLe6RMPV6dLWZLv7f+lyUK2dsznK4WoA9JMRA== X-Received: by 2002:a50:a402:: with SMTP id u2-v6mr459068edb.237.1532572315834; Wed, 25 Jul 2018 19:31:55 -0700 (PDT) Received: from dhcp.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id x13-v6sm241024edx.17.2018.07.25.19.31.54 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 25 Jul 2018 19:31:55 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov , "David S. Miller" , Herbert Xu , Steffen Klassert , Dmitry Safonov <0x7f454c46@gmail.com>, netdev@vger.kernel.org Subject: [PATCH 08/18] xfrm: Add in-kernel groups for compat notifications Date: Thu, 26 Jul 2018 03:31:34 +0100 Message-Id: <20180726023144.31066-9-dima@arista.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20180726023144.31066-1-dima@arista.com> References: <20180726023144.31066-1-dima@arista.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Introduce kernel-only, hidden from userspace groups. Application that bind()ed by kernel to such group will receive netlink messages in compatible ABI on 64-bit kernels. Cc: "David S. Miller" Cc: Herbert Xu Cc: Steffen Klassert Cc: netdev@vger.kernel.org Signed-off-by: Dmitry Safonov --- net/xfrm/xfrm_user.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index bf2ca93edaf5..b123e788488f 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -67,6 +67,29 @@ struct xfrm_userspi_info_packed { __u32 max; } __packed; +/* In-kernel, non-uapi compat groups. + * As compat/native messages differ, send notifications according + * to .bind() caller's ABI. There are *_COMPAT hidden from userspace + * groups for such task. + */ +enum xfrm_nlgroups_kernel { + XFRMNLGRP_COMPAT_MIN = XFRMNLGRP_MAX, + XFRMNLGRP_COMPAT_ACQUIRE, + XFRMNLGRP_COMPAT_EXPIRE, + XFRMNLGRP_COMPAT_SA, + XFRMNLGRP_COMPAT_POLICY, + /* Group messages for the following notifications do not differ + * in size between native and compat structures: + * XFRMNLGRP_AEVENTS, + * XFRMNLGRP_REPORT, + * XFRMNLGRP_MIGRATE, + * XFRMNLGRP_MAPPING, + */ + __XFRMNLGRP_COMPAT_MAX +}; + +#define XFRMNLGRP_KERNEL_MAX (__XFRMNLGRP_COMPAT_MAX - 1) + static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type) { struct nlattr *rt = attrs[type]; @@ -2645,6 +2668,34 @@ static void xfrm_netlink_rcv(struct sk_buff *skb) mutex_unlock(&net->xfrm.xfrm_cfg_mutex); } +static inline void xfrm_nlgrp_compat(unsigned long *groups, + int group, int group_compat) +{ + unsigned long group_bit = 1UL << (group - 1); + + if (*groups & group_bit) { + *groups &= ~group_bit; + *groups |= 1UL << (group_compat - 1); + } +} + +static int xfrm_netlink_bind(struct net *net, unsigned long *groups) +{ + unsigned long uapi_mask = (1UL << XFRMNLGRP_MAX) - 1; + + *groups &= uapi_mask; + + if (!in_compat_syscall()) + return 0; + + xfrm_nlgrp_compat(groups, XFRMNLGRP_ACQUIRE, XFRMNLGRP_COMPAT_ACQUIRE); + xfrm_nlgrp_compat(groups, XFRMNLGRP_EXPIRE, XFRMNLGRP_COMPAT_EXPIRE); + xfrm_nlgrp_compat(groups, XFRMNLGRP_SA, XFRMNLGRP_COMPAT_SA); + xfrm_nlgrp_compat(groups, XFRMNLGRP_POLICY, XFRMNLGRP_COMPAT_POLICY); + + return 0; +} + static inline unsigned int xfrm_expire_msgsize(void) { return NLMSG_ALIGN(sizeof(struct xfrm_user_expire)) @@ -3283,8 +3334,9 @@ static int __net_init xfrm_user_net_init(struct net *net) { struct sock *nlsk; struct netlink_kernel_cfg cfg = { - .groups = XFRMNLGRP_MAX, + .groups = XFRMNLGRP_KERNEL_MAX, .input = xfrm_netlink_rcv, + .bind = xfrm_netlink_bind, }; nlsk = netlink_kernel_create(net, NETLINK_XFRM, &cfg);