From owner-freebsd-hackers@FreeBSD.ORG Tue Jul 24 22:51:59 2007 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 944CC16A417 for ; Tue, 24 Jul 2007 22:51:59 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (gate.funkthat.com [69.17.45.168]) by mx1.freebsd.org (Postfix) with ESMTP id 5E70A13C45D for ; Tue, 24 Jul 2007 22:51:59 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (x54mvj0fpq1rpqqk@localhost.funkthat.com [127.0.0.1]) by hydrogen.funkthat.com (8.13.6/8.13.3) with ESMTP id l6OMpwa7043769; Tue, 24 Jul 2007 15:51:58 -0700 (PDT) (envelope-from jmg@hydrogen.funkthat.com) Received: (from jmg@localhost) by hydrogen.funkthat.com (8.13.6/8.13.3/Submit) id l6OMpvGc043768; Tue, 24 Jul 2007 15:51:57 -0700 (PDT) (envelope-from jmg) Date: Tue, 24 Jul 2007 15:51:57 -0700 From: John-Mark Gurney To: Victor Loureiro Lima Message-ID: <20070724225157.GI99491@funkthat.com> Mail-Followup-To: Victor Loureiro Lima , Daniel Molina Wegener , FreeBSD Hackers References: <200707232052.58485.dmw@unete.cl> <20070724184355.GH99491@funkthat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-Operating-System: FreeBSD 5.4-RELEASE-p6 i386 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html Cc: FreeBSD Hackers , Daniel Molina Wegener Subject: Re: A few questions... X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: John-Mark Gurney List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Jul 2007 22:51:59 -0000 Victor Loureiro Lima wrote this message on Tue, Jul 24, 2007 at 16:35 -0300: > 2007/7/24, John-Mark Gurney : > >Daniel Molina Wegener wrote this message on Mon, Jul 23, 2007 at 20:52 > >-0400: > >> a) Is there any function or variable that tells me which is the > >> root user UID in the system, or root always have 0 and it's > >> an "elegant" option to compare the variables or structure > >> members against zero. > > > >#include > > > >uid == UID_ROOT > > > >> b) Can normal users look for system processes or kernel threads? > > > >Yes, ps does this... > > > > ps(1) either elevates its priviledges during execution, or has some > other way of medling into the afairs of other processes that will > eventually need some higher priviledge status (either that, or I am > really out-dated on modern operational systems) hydrogen,ttypm,/home/johng,503$ls -l /bin/ps -r-xr-xr-x 1 root wheel 31372 May 8 2005 /bin/ps* So, as you see, no suid or sgid necessary for ps to function... FreeBSD exports most/all of the info through sysctl which does not require elevated privs to get... And ps doesn't medling.. it's just a voyeur.. -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."