From owner-freebsd-hackers@FreeBSD.ORG Wed Aug 20 23:58:58 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A4E7616A4BF for ; Wed, 20 Aug 2003 23:58:58 -0700 (PDT) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id 18EB143FF2 for ; Wed, 20 Aug 2003 23:58:58 -0700 (PDT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.12.9/8.12.9) id h7L6wstg041783; Thu, 21 Aug 2003 01:58:54 -0500 (CDT) (envelope-from dan) Date: Thu, 21 Aug 2003 01:58:54 -0500 From: Dan Nelson To: ari Message-ID: <20030821065854.GA11586@dan.emsphone.com> References: <20030817181315.GL55671@episec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030817181315.GL55671@episec.com> X-OS: FreeBSD 5.1-CURRENT X-message-flag: Outlook Error User-Agent: Mutt/1.5.4i cc: freebsd-hackers@freebsd.org Subject: Re: [future patch] dropping user privileges on demand X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Aug 2003 06:58:58 -0000 In the last episode (Aug 17), ari said: > Currently, root is the only user that can actually drop significant > privileges, as root is the only user that has access to such > functions. This is flawed --- any user should be able to relinquish > his privileges, and i've begun a patch to put this into effect. Have you taken a look at Cerb? http://cerber.sourceforge.net/ It does something similar, but uses a C-like language to control a processes actions. This lets you get extremely fine-grained control (allow httpd to bind to only port 80, once), but the rules run as "root", so they can grant as well as revoke privileges. A useful modification would be to allow users to submit their own policies that can only disallow actions (i.e. all arguments and process variables are read-only, and the script can either pass the syscall through or return a failure code, nothing else). -- Dan Nelson dnelson@allantgroup.com