*BSD News Article 48845


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From: Jeff Blattman <n9410493@waldorf.cc.wwu.edu>
Newsgroups: comp.unix.bsd.bsdi.misc
Subject: Re: help:dial in modem access
Date: Fri, 18 Aug 1995 06:12:51 -0700
Organization: Western Washington University
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On 16 Aug 1995, Duncan Campbell wrote:

> Do the following:
> 
> to /etc/gettytab, add the lines
> ###Dhu's entries
> bidir.384|bidirectional line, DCE locked to 38.4kbps, Hard Flow, 8b,noP:\

....

> You should now be able to execute "tip tty01" and have access to your modem.
> You can then set your modem to auto answer by entering 
> ats0=1&w
> 
> Note that dialin/dialout lines have inherent security problems on a
> machine with uncontrolled access.

the obvious reason this works is that tip is setuid root.  yes, it has
unrestricted access to the com port.  giving a user access to a serial
port by changinging perms on /dev/ttyXX seems less insecure than giving
them access to the serial device through a setuid program. 

my question was: is there anyway to give a user access to a dialout 
serial line.  i am specifically using kermit, and don't want to make 
kermit setuid.

it makes sense to me to set group perms on /dev/ttyXX so 'dialer' can use 
it, but as i mentioned, something (getty?) alays resets permissions.

 --
	Jeff Blattman			Administrative Computing Services
	n9410493@admcs.wwu.edu		Western Washington University
					Bellingham, WA 98225
					(360) 650-7709