Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!usc!wuarchive!ukma!psuvax1!psuvax1!okunewck From: okunewck@psuvax1.cs.psu.edu (Phil OKunewick) Newsgroups: alt.hackers Subject: Re: TIOCSTI Message-ID: Date: 10 Jun 91 18:34:40 GMT References: <1991May26.025736.20208@cs.warwick.ac.uk> <1991Jun5.151357.9482@panix.uucp> Sender: news@cs.psu.edu (Usenet) Organization: Random, at best Lines: 36 Approved: JSG3's dog. Nntp-Posting-Host: psuvax1.cs.psu.edu eravin@panix.uucp (Ed Ravin) writes: >Are there any legitimate uses for TIOCSTI that make it worthwhile, or even >worth the inconvenient security risks? Why did the vendors put it in there >in the first place? Yep - here's a hardware ObHack that does something like it: I have several operators doing backups of our systems in the wee hours of the morning. Back before I had my "best and brightest" students doing the backups, it was often easier to read and type on the console myself and have them watch. This is hard to do when I'm at home talking them through things on the phone. So, I wired consoles to I/O ports of other systems using an "and" connection on the rs-232 lines. I could then dial in to psuvax1 and tip to the console of gondor, and remotely take over managing gondor's problem, with the operator watching the console type things itself. (One guy continued to read the consle output to me after I had told him what I was doing, and didn't really realize what was happenning until I typed "Hi Fred.") Even when gondor was down in single user mode, I could still dial in to it. I often used this to remotely fix the vaxen when I got middle-of-the-night phone calls about a crash. There are a couple problems with this idea - the main one is that the tip line must be _secure_. If the port isn't protected from the world, then the random cracker could have all sorts of remote fun on the console. Now that we've got Suns, there's a risk of a "break" accidentally happenning when I connect/disconnect. Since I've got good operators and stable systems now, the tip-to-consoles aren't worth the risk any more. But if they're ever needed, they're easy to set up again. Admittedly this is a hardware version of remote terminal control, but it does a very similar function.