Messages in this thread | | | Date | Fri, 16 Apr 1999 14:12:39 -0400 (EDT) | From | "David L. Parsley (lkml account)" <> | Subject | Re: caps in elf headers: use the sticky bit! |
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Hi David,
On Fri, 16 Apr 1999, David Lang wrote:
> -----BEGIN PGP SIGNED MESSAGE----- > > On Thu, 15 Apr 1999, Theodore Y. Ts'o wrote: > > > > > Date: Thu, 15 Apr 1999 16:07:35 -0700 (PDT) > > From: David Lang <dlang@diginsite.com> > > > > As for the NFS issue, there are situations where NFS can be used in a > > (at least semi)secure environment. If the NFS traffic is on a dedicated > > LAN (often done for performance anyway) then the only way that NFS can be > > a problem is if one of your machines in hacked into anyway. The ability to > > use capabilities on NFS mounted files would significantly help in server > > farm situations. > > > > So if I can manage to hack into one of your machines, (say, the one > > which is running the sendmail that didn't get updated to fix the > > sendmail security bug of the week) I get to break into all of the > > rest?!? > > > > This is real security? I think not. > > But if we are using capabilities on all the machines, hacking into > sendmail won't give you this sort of access (or am I misunderstanding what > we are after here?)
Well, I certainly am not in favor of trying to hack capabilities to work in a heterogenous environment. I see no reason why nfs can't be hacked so that two Linux machines can use capabilities over nfs. As far as IRIX, Linux 2.0 nfs servers, ... I just don't see this as an absolute necessity, especially when it adds what I consider unneeded bloat and complexity to our implementation.
Of course, at least one gentleman from SGI has been very helpful in this thread; perhaps IRIX will get patched for this. ;-)
> > A real world example. you setup a web server farm with the common > > files/binarys NFS mounted. > > > > Disk space is cheap these days. $300 USD will buy you 20 gigabytes of > > space; a complete Linux system worth of binaries is maybe 1, 2 gigs tops > > for a fully loaded system. If you're not willing to pay $15-30 extra > > per server so that each system can have its own copy of its system > > software, you're not serious about your system security. > > > > Besides, running your server farm with standalone disk increases your > > performance and your robustness, since you remove a single point of > > failure. (If your NFS server crashs, your entire server farm goes out.) > > > > The reason to use the NFS server is not cost (A good, redundant NFS server > can be very expensive) the reason is ease of management, if you only have > one copy of the data the possibility that different servers have different > info just isn't there.
For binaries, hack rdist; for _data_, just use nfs as is w/o caps.
cheers, David
- -- David L. Parsley Network Specialist City of Salem Schools
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