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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6A039C31E40 for ; Mon, 10 Jun 2019 17:11:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4BF2220820 for ; Mon, 10 Jun 2019 17:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728407AbfFJRLN (ORCPT ); Mon, 10 Jun 2019 13:11:13 -0400 Received: from ms.lwn.net ([45.79.88.28]:44806 "EHLO ms.lwn.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726514AbfFJRLM (ORCPT ); Mon, 10 Jun 2019 13:11:12 -0400 Received: from lwn.net (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id C166D2BB; Mon, 10 Jun 2019 17:11:11 +0000 (UTC) Date: Mon, 10 Jun 2019 11:11:10 -0600 From: Jonathan Corbet To: David Howells Cc: viro@zeniv.linux.org.uk, raven@themaw.net, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-block@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 06/13] keys: Add a notification facility [ver #4] Message-ID: <20190610111110.72468326@lwn.net> In-Reply-To: <155991709983.15579.13232123365803197237.stgit@warthog.procyon.org.uk> References: <155991702981.15579.6007568669839441045.stgit@warthog.procyon.org.uk> <155991709983.15579.13232123365803197237.stgit@warthog.procyon.org.uk> Organization: LWN.net MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, 07 Jun 2019 15:18:19 +0100 David Howells wrote: > Add a key/keyring change notification facility whereby notifications about > changes in key and keyring content and attributes can be received. > > Firstly, an event queue needs to be created: > > fd = open("/dev/event_queue", O_RDWR); > ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, page_size << n); > > then a notification can be set up to report notifications via that queue: > > struct watch_notification_filter filter = { > .nr_filters = 1, > .filters = { > [0] = { > .type = WATCH_TYPE_KEY_NOTIFY, > .subtype_filter[0] = UINT_MAX, > }, > }, > }; > ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter); > keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01); One little nit: it seems that keyctl_watch_key is actually spelled keyctl(KEYCTL_WATCH_KEY, ...). jon