From patchwork Thu Dec 23 15:39:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 12698394 X-Patchwork-Delegate: kuba@kernel.org 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 2883DC43219 for ; Thu, 23 Dec 2021 15:40:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349031AbhLWPko (ORCPT ); Thu, 23 Dec 2021 10:40:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33794 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349013AbhLWPkm (ORCPT ); Thu, 23 Dec 2021 10:40:42 -0500 Received: from mail-ed1-x52f.google.com (mail-ed1-x52f.google.com [IPv6:2a00:1450:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E79ABC061757; Thu, 23 Dec 2021 07:40:41 -0800 (PST) Received: by mail-ed1-x52f.google.com with SMTP id o6so22972532edc.4; Thu, 23 Dec 2021 07:40:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=dkmS0Cn+xGZLK+jdSmt5kOascj8B8GCiGD14/T3W7CI=; b=T9lR1BqjJlLABep1NTKOI6UKfJb9U+22sWOMnYNzIdJM5fRvvnC1GNrrb0pw0RzFgz yjgz+o4y8jEl2p6hgEJgarlhrVB9wJT1XZq32PdiRuBRXaF1MoJDI8s33ddtUb7FqzUG 7vlJsXevJ3whHk+UWV1sf5s9NJPqh54AmDdK7uqL3uRrcIwpgGS3cTCE36fg58yyP0pV VK0aSNsqeWctt15JrI7UTTv0PtvlGZDP2dgokjq3mDP2N6iDzjFfyvalomZV6bzTfCUA 2juXiqh5U+h4eBOXP7XS3vvOMCQJ0E9xBf8+GIZXg0wPyMKLjRucKnPdyW/zJNlDT1Cs +0hQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=dkmS0Cn+xGZLK+jdSmt5kOascj8B8GCiGD14/T3W7CI=; b=elZP4w2Paa/inXVG2JiN5QhEG3FfBgmlXsUpdphQm31XJjQ2/6PMTbkECVBAd7SKB6 9LosS2CSFbne87hW20D7Ibwh5AFF3P9UaHC7nhw7lSDwBTesz6T+Om38AuyCSeevAxIS eliZTwCwg8Oo9D4dg4d9mmmi7Idbza1ToPkNaeZ9kMi5vb8Dkp5Zp/lApHSGoNYdZIcL P7ogUEYvyK6PenbBqEc/21xZ5FQo8LN4QyVdWpvJ/76BiXtNre7W7QWsfAuR4XQy5z0d m1VXf2VCvKQS7Quehwvo7BAOX2IgmJ3yklQKdgegh3vgqQ9TLZCD6A8UZTYSFaJJbRhe n+tg== X-Gm-Message-State: AOAM530qs7fkbNXoobQHc2aFkJRcIAy8tMYuyPHm5sA03sYxK1T7W3J6 B7noSXFPKcL27RlEn3yOh5Y= X-Google-Smtp-Source: ABdhPJx+PaQa0e19Kafpqo5KgHmsytvqhKFXKZIMk4610aJntPYi1bjuNgzeKI1ey547amYqbqOo9Q== X-Received: by 2002:a17:906:5208:: with SMTP id g8mr2312261ejm.634.1640274040511; Thu, 23 Dec 2021 07:40:40 -0800 (PST) Received: from ponky.lan ([2a04:241e:501:3870:7c02:dfc6:b554:ab10]) by smtp.gmail.com with ESMTPSA id bx6sm2088617edb.78.2021.12.23.07.40.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Dec 2021 07:40:39 -0800 (PST) From: Leonard Crestez To: David Ahern , Eric Dumazet , Philip Paeps , Dmitry Safonov <0x7f454c46@gmail.com> Cc: Shuah Khan , "David S. Miller" , Herbert Xu , Kuniyuki Iwashima , Hideaki YOSHIFUJI , Jakub Kicinski , Yuchung Cheng , Francesco Ruggeri , Mat Martineau , Christoph Paasch , Ivan Delalande , Priyaranjan Jha , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 02/19] docs: Add user documentation for tcp_authopt Date: Thu, 23 Dec 2021 17:39:57 +0200 Message-Id: <68b9a766f7ea045f0ea56f27d7523abb41daab37.1640273966.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: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@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 58bc8cd367c6..f5c324a060d8 100644 --- a/Documentation/networking/index.rst +++ b/Documentation/networking/index.rst @@ -100,10 +100,11 @@ 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