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Path: utzoo!linus!decvax!tektronix!orca!andrew
From: andrew@orca.UUCP (Andrew Klossner)
Newsgroups: net.unix-wizards
Subject: Re: Why you shouldn't chmod 500 /bin/login
Message-ID: <1180@orca.UUCP>
Date: Sat, 24-Nov-84 20:25:51 EST
Article-I.D.: orca.1180
Posted: Sat Nov 24 20:25:51 1984
Date-Received: Sun, 25-Nov-84 04:06:28 EST
References: <5807@brl-tgr.ARPA> <269@ut-sally.UUCP> <1173@orca.UUCP> <1250@utah-gr.UUCP>
Organization: Tektronix, Wilsonville OR
Lines: 16

>In article <1173@orca.UUCP> andrew@orca.UUCP (Andrew Klossner) writes:
>>
>>The big win of the builtin shell "login" command is that it logs me out
>>and lets you log in without hanging up the modem line.  If you chmod
>>500 /bin/login, then the line will drop when exec("/bin/login") fails.
>>Inconvenient.
>
>An easy fix (if you have source) is to have /bin/login check if its ppid
>== 1, and exit if not.  Foils those recursive logins right away.

If you use "rlogin", then during network connections, login is run as a
child of a child of /etc/rlogind.  Thus, if you install this fix, you
disable remote logins.

  -- Andrew Klossner   (decvax!tektronix!orca!andrew)       [UUCP]
                       (orca!andrew.tektronix@csnet-relay)  [ARPA]