Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!cs.utexas.edu!rutgers!netnews.upenn.edu!jes From: jes@mbio.med.upenn.edu (Joe Smith) Newsgroups: comp.unix.i386 Subject: Re: Is DOS under Unix immune? Message-ID: Date: 4 Aug 90 00:36:55 GMT References: <15722@bfmny0.BFM.COM> Sender: news@netnews.upenn.edu Distribution: comp Organization: University of Pennsylvania, Philadelphia, PA Lines: 36 In-reply-to: tneff@bfmny0.BFM.COM's message of 3 Aug 90 10:23:57 GMT > (4) The UNIX filesystem at the 'stdio' level, through a TSR resident > under DOS (Redirect) that uses hooks to the VP/ix executive. Would it be possible then for all your 'DOS' files to really be UNIX files, with the appropriate ownership/permissions (e.g. *real* read-only directories), which would be inaccessible to the DOS executable? I mean, just making your COMMAND.COM owned by root, and mode 755 would be sufficient to stop several of the common viruses (I presume VP/ix doesn't support the setuid call, and that the Unix permission bits are mapped appropriately). Is that sort of thing possible? > But any virus that's dependent on such things as precise clock timing > or transparent access to the controller hardware seems likely to fail, > although it could certainly lock up the box in failing. Aren't hardware (i/o) accesses trapped and 'tamed' in some way? I mean, I could care less what the goofy DOS software does with my speaker, but I'd be real uncomfortable knowing it could start fiddling with the disk controller registers. As I think about it I guess it's just impossible to accommodate all the DOS software that assumes it has free reign of the machine without really giving it that kind of access. BTW, there was apparently an article in this thread from Peter da Silva which I couldn't retrieve. I'd appreciate it if someone could pass that along by e-mail.