Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 4 Dec 2002 20:27:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 4 Dec 2002 20:27:05 -0500 Received: from holly.csn.ul.ie ([136.201.105.4]:21642 "EHLO holly.csn.ul.ie") by vger.kernel.org with ESMTP id ; Wed, 4 Dec 2002 20:27:04 -0500 Date: Thu, 5 Dec 2002 01:34:41 +0000 (GMT) From: Dave Airlie X-X-Sender: airlied@skynet To: linux-kernel@vger.kernel.org Subject: Process verification while running Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1705 Lines: 42 Hi, I have an embedded Linux project that requires (by standards + laws) that all code running in the system be verified against prestored CRCs at a number of stages of execution.... (and they mean all code : both kernel and userspace) to protect against memory issue and tampering. I don't wish to debate the merits of these ideas, they are cast in stone, what I want to know what is the best approach to doing this under Linux? There is no swap in the system, and all process will be running with mlockall(). For the kernel I'm going to add a kernel thread that loops over the text segment verifying integrity. For userspace I was initially going to use a userspace daemon that reads via /proc/pid/mem interface and tests the text segments against what I hope is in there.. but this seems to be a problem as I need to ptrace attach the process (which starts sending SIGSTOPs around when the process gets a signal) to get a /proc/pid/mem. My other option is to implement my own kernel module to do the work, and have a kernel thread running around.. I'd have to feed it the CRCs and stuff at the start and let it go... Could I remove the check that stops other processes reading /proc/pid/mem? safely enough considering this system runs embedded with very little scope for outside interference... Thanks, Dave. -- David Airlie, Software Engineer http://www.skynet.ie/~airlied / airlied@skynet.ie pam_smb / Linux DecStation / Linux VAX / ILUG person - 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/