From owner-freebsd-hackers Sun May 31 05:24:15 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id FAA18915 for freebsd-hackers-outgoing; Sun, 31 May 1998 05:24:15 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from implode.root.com (implode.root.com [198.145.90.17]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id FAA18838 for ; Sun, 31 May 1998 05:22:59 -0700 (PDT) (envelope-from root@implode.root.com) Received: from implode.root.com (localhost [127.0.0.1]) by implode.root.com (8.8.5/8.8.5) with ESMTP id FAA07750; Sun, 31 May 1998 05:22:28 -0700 (PDT) Message-Id: <199805311222.FAA07750@implode.root.com> To: Terry Lambert cc: abial@nask.pl (Andrzej Bialecki), freebsd-hackers@FreeBSD.ORG Subject: Re: Signed executables, safe delete etc. In-reply-to: Your message of "Sun, 31 May 1998 09:34:54 -0000." <199805310934.CAA19826@usr04.primenet.com> From: David Greenman Reply-To: dg@root.com Date: Sun, 31 May 1998 05:22:28 -0700 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG >> You can wonder what all this is for: it helps to ensure that no element of >> the system has been changed without you knowing it. It could be performed >> during startup of the system, and/or just before executing each binary (as >> far as I understand it, ELF allows to put pretty arbitrary sections into >> the binary). Moreover, this helps to ensure that the system won't boot >> without proper authorization, and even if someone steals it, it could >> refuse to give in (this would require encrypting the disk contents, of >> course - that's why I said about bootblocks...). > >VMS will not mark an executable as executable unless the VMS linker is >the program that created the file. > >In general, the VMS mechanism prevents programs without SYSPRIV from >generating programs that can be loaded as executable. The mechanism >prevents the common case in BSD-land of LISP and other binaries that >extend the data space of executables with code. > >Typically, this is a bad trade-off, favoring security over usability. Terry, sometimes I think we exist in different realities. First of all, any user can set a file as executable in VMS. It does not require any special privileges. Second, there is no "SYSPRIV" privilege. There is a "SYSPRV" privilege, however, that allows the holder access system resources as if he had a system UIC. One does not have to have a system UIC to change file permissions (including the executable flag); all one needs is to be the owner of the file - just like it is in Unix. Third, LISP works just fine in VMS, including dynamic compilation and process extension. -DG David Greenman Co-founder/Principal Architect, The FreeBSD Project To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message