From owner-freebsd-security Fri Aug 14 03:34:24 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id DAA02280 for freebsd-security-outgoing; Fri, 14 Aug 1998 03:34:24 -0700 (PDT) (envelope-from owner-freebsd-security@FreeBSD.ORG) Received: from mail.ftf.dk (mail.ftf.dk [129.142.64.2]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id DAA02267 for ; Fri, 14 Aug 1998 03:34:22 -0700 (PDT) (envelope-from regnauld@deepo.prosa.dk) Received: from mail.prosa.dk ([192.168.100.254]) by mail.ftf.dk (8.8.8/8.8.8/gw-ftf-1.0) with ESMTP id MAA17244 for ; Fri, 14 Aug 1998 12:39:06 +0200 (CEST) (envelope-from regnauld@deepo.prosa.dk) Received: from deepo.prosa.dk (deepo.prosa.dk [192.168.100.10]) by mail.prosa.dk (8.8.8/8.8.5/prosa-1.1) with ESMTP id MAA20454 for ; Fri, 14 Aug 1998 12:41:25 +0200 (CEST) Received: (from regnauld@localhost) by deepo.prosa.dk (8.8.8/8.8.5/prosa-1.1) id MAA06165; Fri, 14 Aug 1998 12:32:40 +0200 (CEST) Message-ID: <19980814123240.63855@deepo.prosa.dk> Date: Fri, 14 Aug 1998 12:32:40 +0200 From: Philippe Regnauld To: freebsd-security@FreeBSD.ORG Subject: Fwd: "Using capabilties aaginst shell code" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.88e X-Operating-System: FreeBSD 2.2.6-RELEASE i386 Phone: +45 3336 4148 Address: Ahlefeldtsgade 16, 1359 Copenhagen K, Denmark Organization: PROSA Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org (see message below) Is this any form of restriction that can be implemented in *BSD systems ? I.e.: restricting system calls to certain classes of daemons ? As mentioned in the example below, why should POPd be allowed to exec() ? This seems like a very sane approach (of course, it implies knowledge/auditing of the code). Then we could have certain untrusted (i.e.: running as root) daemons launched in such an environment, on top of being chroot()ed. -----Forwarded message from Duncan Simpson ----- From: Duncan Simpson Subject: Using capabilties aaginst shell code To: BUGTRAQ@NETSPACE.ORG Date: Wed, 12 Aug 1998 21:33:51 +0200 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The development of capabilities with Linux (and some section of POSIX, if the header is to be believed) creates an opportunity for tightening security by sandboxing daemons---imapd and popd have no legitimate use for various system calls, for example. In particular exec is fundamental to most buffer overrun shellcode and not required by many daemons. [...] -----End of forwarded message----- -- -[ Philippe Regnauld / sysadmin / regnauld@deepo.prosa.dk / +55.4N +11.3E ]- The Internet is busy. Please try again later. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe security" in the body of the message