[30] in bugtraq
Re: Internet Worm
daemon@ATHENA.MIT.EDU (jim@Tadpole.COM)
Tue Oct 18 16:59:25 1994
From: jim@Tadpole.COM
Date: Tue, 18 Oct 1994 13:57:56 -0500
To: perry@imsi.com, schwartz@galapagos.cse.psu.edu
Cc: bugtraq@fc.net, jmb@kryten.Atinc.COM
Sun (at least in SunOS 4) didn't do any "mucking about" with
libresolv and YP in libc. ypserv(e) is responsible for
consulting the DNS, if the NIS maps (host.byname/byaddr) are
setup with a special key/value pair. Things are different in
Solaris.
The resolv+ package shows exactly how to replace routines in
the libc.so/sa files such that the gethostbyname()/gethostbyaddr()
lookups happen via the DNS (or NIS, or just the /etc/host file, it
depends on how you configure things). Similar things could be done
for any routine in libc, or any other shared library, for that matter.
[Unfortunately, 'rcp' and everything in /sbin (SunOS 4 again) are staticly
linked, so if 'rcp' is important to you and you want to use the resolv+
functionality, you'll have to find the BSD source and build a copy for
yourself.]
Replacing ruserok() and friends should be trivial.
Jim