From patchwork Thu Aug 18 19:59:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 12947781 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6E51C32789 for ; Thu, 18 Aug 2022 20:01:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345703AbiHRUA6 (ORCPT ); Thu, 18 Aug 2022 16:00:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232582AbiHRUAW (ORCPT ); Thu, 18 Aug 2022 16:00:22 -0400 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD4ECD11C8; Thu, 18 Aug 2022 13:00:21 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id kb8so5194619ejc.4; Thu, 18 Aug 2022 13:00:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc; bh=6LjuhIC/pbHS+8spopbsWARAYbdtibeJdvNxgS2b0Q0=; b=DnEEg/NVdSgE+1sW6RKuwbjtxKGZpWutEE0ukCallUqZPOtl5DGAY/60C/teKchf9B jMwhuG22I9Ro7Xhqu4aM1nDNACE70KAeTQOgM1050z/FQ5AtSNyfdJXQuZUu6Wko3aur c4kdKHPUSPJpYLF4YppAyrsKg+Yu6dbzXmZ1DhtX7j3YCGIJMoVb53guIlO2VtJOpA2F jQNml7DfIPOTBaKwhiOR6pw+px3KYtbsw0jNW/P+l2M+n6DiE00uQ5HKKxGwtkKR3FF3 HLoPu5AZjj+DONA0RrTp2w7EtjcVAYJD/ddZUT9vB35pr/PO5SIG4rVAd9IVd40+63vs x+qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc; bh=6LjuhIC/pbHS+8spopbsWARAYbdtibeJdvNxgS2b0Q0=; b=KuA5VDrkdz9lBzETOK5EQeP/yh1sHAJ6hf6UAmV9Y3QlB2dKz2YQM71p2PCPpVIXsv JCkoMEdoRkBRkh+CzvsTAo1aOaOr3TU6QWCZ6CbayrdFp4kk7fxMoKlKfMh7T6v0KK1j GTgpjkgK8qSS154BdWFLjS0w2+CPbumfc5ZYNEWb0FyiaYfQnuH4u5BCq06IgZZtMbQw xHZbN8Zzz5qp8N/TnzFDvAksN7qVtmPRkGD1zH2jwPWeYDHbC6NzdK3nP5gOwfTYB62J yxEEIDBW8RgxaA9T0jiqqtDuFLqk8P7vY3D2kG3uu7Xmtc7PSZVOr3nmc2I+1HN2KbH4 Cp0A== X-Gm-Message-State: ACgBeo2P+vEL/Q+KXHuToJ4d5+oe22qvG0Vmx0173KPp3qfCYup2Q/Lj Z03a1AaUcM8EuchUztfz4sw= X-Google-Smtp-Source: AA6agR7pucv+3lef3sfcTrOznJ+6O5RQdTj3b/E418awSUW7na9pwOsT7lFDV/VmSwVA0AfCvoxARQ== X-Received: by 2002:a17:907:a40f:b0:730:c4ce:631c with SMTP id sg15-20020a170907a40f00b00730c4ce631cmr2743974ejc.362.1660852820274; Thu, 18 Aug 2022 13:00:20 -0700 (PDT) Received: from localhost.localdomain ([2a04:241e:502:a080:17c8:ba1c:b6f3:3fe0]) by smtp.gmail.com with ESMTPSA id fw30-20020a170907501e00b00722e4bab163sm1215087ejc.200.2022.08.18.13.00.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Aug 2022 13:00:19 -0700 (PDT) From: Leonard Crestez To: David Ahern , Eric Dumazet , Philip Paeps Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Shuah Khan , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , Francesco Ruggeri , Mat Martineau , Christoph Paasch , Ivan Delalande , Caowangbao , Priyaranjan Jha , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 02/26] docs: Add user documentation for tcp_authopt Date: Thu, 18 Aug 2022 22:59:36 +0300 Message-Id: <8594c8d9de865b7d4d6ec3a783758fec23a70104.1660852705.git.cdleonard@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org The .rst documentation contains a brief description of the user interface and includes kernel-doc generated from uapi header. Signed-off-by: Leonard Crestez --- Documentation/networking/index.rst | 1 + Documentation/networking/tcp_authopt.rst | 51 ++++++++++++++++++++++++ 2 files changed, 52 insertions(+) create mode 100644 Documentation/networking/tcp_authopt.rst diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst index 03b215bddde8..294b87137cd2 100644 --- a/Documentation/networking/index.rst +++ b/Documentation/networking/index.rst @@ -103,10 +103,11 @@ Contents: strparser switchdev sysfs-tagging tc-actions-env-rules tcp-thin + tcp_authopt team timestamping tipc tproxy tuntap diff --git a/Documentation/networking/tcp_authopt.rst b/Documentation/networking/tcp_authopt.rst new file mode 100644 index 000000000000..72adb7a891ce --- /dev/null +++ b/Documentation/networking/tcp_authopt.rst @@ -0,0 +1,51 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================= +TCP Authentication Option +========================= + +The TCP Authentication option specified by RFC5925 replaces the TCP MD5 +Signature option. It similar in goals but not compatible in either wire formats +or ABI. + +Interface +========= + +Individual keys can be added to or removed through an TCP socket by using +TCP_AUTHOPT_KEY setsockopt and a struct tcp_authopt_key. There is no +support for reading back keys and updates always replace the old key. These +structures represent "Master Key Tuples (MKTs)" as described by the RFC. + +Per-socket options can set or read using the TCP_AUTHOPT sockopt and a struct +tcp_authopt. This is optional: doing setsockopt TCP_AUTHOPT_KEY is sufficient to +enable the feature. + +Configuration associated with TCP Authentication is global for each network +namespace, this means that all sockets for which TCP_AUTHOPT is enabled will +be affected by the same set of keys. + +Manipulating keys requires ``CAP_NET_ADMIN``. + +Key binding +----------- + +Keys can be bound to remote addresses in a way that is somewhat similar to +``TCP_MD5SIG``. By default a key matches all connections but matching criteria can +be specified as fields inside struct tcp_authopt_key together with matching +flags in tcp_authopt_key.flags. The sort of these "matching criteria" can +expand over time by increasing the size of `struct tcp_authopt_key` and adding +new flags. + + * Address binding is optional, by default keys match all addresses + * Local address is ignored, matching is done by remote address + * Ports are ignored + +RFC5925 requires that key ids do not overlap when tcp identifiers (addr/port) +overlap. This is not enforced by linux, configuring ambiguous keys will result +in packet drops and lost connections. + +ABI Reference +============= + +.. kernel-doc:: include/uapi/linux/tcp.h + :identifiers: tcp_authopt tcp_authopt_flag tcp_authopt_key tcp_authopt_key_flag tcp_authopt_alg