From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH RFC] tpm: define a command filter Date: Mon, 23 Jan 2017 17:19:18 -0700 Message-ID: <20170124001918.GA29735@obsidianresearch.com> References: <20170124000258.16818-1-jarkko.sakkinen@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170124000258.16818-1-jarkko.sakkinen@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Jarkko Sakkinen Cc: tpmdd-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, Peter Huewe , Marcel Selhorst , open list List-Id: tpmdd-devel@lists.sourceforge.net On Tue, Jan 24, 2017 at 02:02:52AM +0200, Jarkko Sakkinen wrote: > This commit adds a command filter for whitelisting a set of commands in > a TPM space. When a TPM space is created through /dev/tpms0, no > commands are allowed. The user of the TPM space must explicitly define > the list of commands allowed before sending any commands. This ioctl is > a one shot call so that a resource manager daemon can call it before > sending the file descriptor to the client. I don't think it makes sense to have a daemon in user space that passes an open'd /dev/tpms0 FD directly to a client.. It is trivial and more powerful to just proxy the messages. Can you see some reason why passing a FD through a daemon would make sense? The earlier discussion with James was to have some way to apply a global command filter to all tpms0 users with the idea that the 'right' restricted command set would enable a 0666 cdev node, and no daemon. > Signed-off-by: Jarkko Sakkinen > 1. This patch applies on top of 'tabrm4' brach. > 2. Only compilation is tested (just drafted the idea) > drivers/char/tpm/tpm-interface.c | 12 +++++-- > drivers/char/tpm/tpm.h | 1 + > drivers/char/tpm/tpm2-space.c | 7 ++++ > drivers/char/tpm/tpms-dev.c | 75 ++++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/tpms.h | 29 ++++++++++++++++ BTW, don't forget to update kbuild when you add uapi files... Applies to other patches.. Jason