From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Getz Subject: Re: IRQF_SAMPLE_RANDOM question... Date: Tue, 7 Apr 2009 18:30:37 -0400 Message-ID: <200904071830.38081.rgetz@blackfin.uclinux.org> References: <200904061430.26276.rgetz@blackfin.uclinux.org> <1239116251.14392.133.camel@calx> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: "Matt Mackall" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: "Chris Peterson" Return-path: Received: from nwd2mail11.analog.com ([137.71.25.57]:27927 "EHLO nwd2mail11.analog.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755451AbZDGW3T (ORCPT ); Tue, 7 Apr 2009 18:29:19 -0400 In-Reply-To: Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: On Tue 7 Apr 2009 17:39, Chris Peterson pondered: > 1. Are there any new add_*_randomness() functions that could be added? I can think of - USB, serial, SDIO - but if any are heavily loaded with constant data - their randomness reduces, and becomes less useful. if it is the normal use case - then these might be better - but it is a function of the local users's use of the device - and is not remotely attackable. > Some userspace daemons like EGD (running as root) feed random system > info (e.g. vmstat) into /dev/random. But how many Linux distros > actually run entropy-gathering daemons by default? Not many that I can find. > Would /dev/random > be more secure if entropy-gathering daemons were replaced with new > kernel functions like add_vmstat_randomness() or add_ps_randomness()? on embedded and server - it is likely most of ps (except load) will be pretty stable - even vmstat - might be on more stable than you think on embedded - which starts processes, allocates memory, and then just runs forever..... > 2. Are there any other functions that could be calling the existing > add_*_randomness() functions? Currently: > > * add_input_randomness() is called from input_event(). Could be added in the serial core? usb? spi? i2c? > * add_interrupt_randomess() is called from handle_IRQ_event() if > IRQF_SAMPLE_RANDOM is set. > * add_disk_randomness() is called from blk_end_io() and __blk_end_request().