Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761891AbZDGW3b (ORCPT ); Tue, 7 Apr 2009 18:29:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758263AbZDGW3U (ORCPT ); Tue, 7 Apr 2009 18:29:20 -0400 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 X-IronPort-AV: E=Sophos;i="4.39,339,1235970000"; d="scan'208";a="69212057" From: Robin Getz Organization: Blackfin uClinux org To: "Chris Peterson" Subject: Re: IRQF_SAMPLE_RANDOM question... Date: Tue, 7 Apr 2009 18:30:37 -0400 User-Agent: KMail/1.9.5 CC: "Matt Mackall" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <200904061430.26276.rgetz@blackfin.uclinux.org> <1239116251.14392.133.camel@calx> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-ID: <200904071830.38081.rgetz@blackfin.uclinux.org> X-OriginalArrivalTime: 07 Apr 2009 22:28:18.0171 (UTC) FILETIME=[266084B0:01C9B7D0] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1681 Lines: 37 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(). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/