Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!bloom-beacon!snorkelwacker!spdcc!dyer From: dyer@spdcc.COM (Steve Dyer) Newsgroups: comp.unix.i386 Subject: Re: RFS is by far better that NFS! Message-ID: <884@ursa-major.SPDCC.COM> Date: 16 Dec 89 05:55:44 GMT References: <218@inpnms.UUCP> <221@inpnms.UUCP> Reply-To: dyer@ursa-major.spdcc.COM (Steve Dyer) Distribution: na Organization: S.P. Dyer Computer Consulting, Cambridge MA Lines: 19 Yes, it's true. An amazingly big security hole once you start thinking about it. I thought that Sun had some "secure RPC" feature in recent releases which suffices to limit its impact, but I don't know the details. At Project Athena, we added a small amount of code to our NFS servers such that every uid (not just root) is mapped to "nobody" unless that uid/IP address pair has a "uid mapping structure", a new data structure residing in the NFS server kernel. UID mapping structures are securely installed on the server using a new rpc.mountd RPC call which uses the Kerberos authentication system. We have an application which runs on the client called "attach" which integrates name service, authentication and the mount protocol. -- Steve Dyer dyer@ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer dyer@arktouros.mit.edu, dyer@hstbme.mit.edu