Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!ptsfa!ames!oliveb!jerry From: jerry@oliveb.UUCP Newsgroups: comp.unix.wizards Subject: Re: UNIX classified operation - (nf) Message-ID: <1894@oliveb.UUCP> Date: Wed, 8-Jul-87 17:14:35 EDT Article-I.D.: oliveb.1894 Posted: Wed Jul 8 17:14:35 1987 Date-Received: Sat, 11-Jul-87 13:58:35 EDT References: <175@uw-apl.UUCP> <8300007@iaoobelix.UUCP> <1110@rayssd.RAY.COM> Reply-To: jerry@oliveb.UUCP (Jerry F Aguirre) Organization: Olivetti ATC; Cupertino, Ca Lines: 18 In article <1110@rayssd.RAY.COM> dhb@rayssd.RAY.COM (David H. Brierley) writes: >Protecting normal users from reading the raw disk is not only easy, >it is essential to system security. All block and character device >entries for the various disk drives (i.e. /dev/rhp0a, /dev/rra0a) >should be made mode 600 and owned by either root or some other "secure" >account. If the raw disk is readable by general users it effectively >overrides any file permissions that other users might set up. Actually you should consider making them mode 640, owned by root and with group set to the group your operators are in. This allows them to do dumps without being root. Of course this depends on the procedures you use for backup but it can add an extra measure of security. The /dev/mem and /dev/kmem entries are another area that should have similar protection. On 4.3BSD they are mode 640 with a group of "kmem". This allows programs like "ps" to be set group id to kmem instead of set uid to root. Jerry Aguirre