From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Aring Subject: RFC: right userspace interface for providing 6lowpan contexts Date: Wed, 18 Nov 2015 00:03:57 +0100 Message-ID: <20151117230332.GA6219@omega> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: linux-bluetooth@vger.kernel.org, linux-wpan@vger.kernel.org, kernel@pengutronix.de, mcr@sandelman.ca, lukasz.duda@nordicsemi.no, martin.gergeleit@hs-rm.de, marcel@holtmann.org To: netdev@vger.kernel.org Return-path: Received: from mail-wm0-f52.google.com ([74.125.82.52]:37869 "EHLO mail-wm0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932286AbbKQXEF (ORCPT ); Tue, 17 Nov 2015 18:04:05 -0500 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Hi, I recently sent some 6lowpan stateful compression patches to netdev. It provides to setup 6lowpan contexts entries (ipv6 prefixes and prefix-length by id) via debugfs manually at the moment. This means, it works when all other "network nodes" also sets the same ID's inside the table _manually_. Well, it exists a RFC (and others) [0] to share the prefixes (contexts) inside the network without manually manipulate the tables. The rfc6775 describes new ICMPv6 option fields and ICMPv6 messages. I want to talk about the ICMPv6 messages which are handled by userspace to handle the necessary option fields. The case is now, rfc6775 describes 6CO option fields for RA [1]. For this reason we need an userspace interface to manipulate/get the current context entries which are currently stored inside the kernel. These context tables are: - A per interface declaration. - Maximum 16 entries. - Provides: ID, address prefix (can also 128 bit) and prefix-len My question is what would be the best to do a userspace interface: Note: These context tables should only available for 6LoWPAN interface types, which means: ARPHRD_6LOWPAN. - netlink entry? - RTNL netlink? - 6lowpan netlink? - We don't currently has any netlink connection for net/6lowpan branch, but it's possible to add one special "6lowpan" netlink family to provide all 6LoWPAN configuration which belongs to ARPHRD_6LOWPAN. We need such interface of course for other settings as well. - per interface, sysfs entry - should _maybe_ looks like the debugfs entries. Thanks for any suggestion. - Alex [0] https://tools.ietf.org/html/rfc6775 [1] https://tools.ietf.org/html/rfc6775#section-5.4