[comp.protocols.nfs] PCNFS gid

jbvb@ftp.COM (James Van Bokkelen) (04/21/89)

In article <462@sequoia.UUCP>, teb@sequoia.UUCP (Thomas E. Bernhard) writes:
> How can I set my group id different from what the passwd file returns?
> The 'net name' command returns me with a group id but I belong to other
> groups (in yp database group). How can I set my group id for access to
> these other groups?

The fact that PCNFSD returns the UID/GID you wind up using is central
to the current "security" mechanism of NFS on DOS.  If you could set
it yourself, there would have to be some way of limiting the values you
could set.  One could enhance the authentication protocol implementation,
so that a list of valid UID/GIDs was returned, but that is a back-door route
to a "heuristic piratical NFS", which figures out which UID/GID can perform
the requested operation and switches to them on the fly...

The real solution is to change both the clients and servers so that
something substantial is passed in the "authentication" field.  I think
that Sun plans this in the next version of RPC.


-- 
James B. VanBokkelen		26 Princess St., Wakefield, MA  01880
FTP Software Inc.		voice: (617) 246-0900  fax: (617) 246-0901

mike@relgyro.stanford.edu (Mike Macgirvin) (04/21/89)

In article <642@ftp.COM> jbvb@ftp.COM (James Van Bokkelen) writes:
>In article <462@sequoia.UUCP>, teb@sequoia.UUCP (Thomas E. Bernhard) writes:
>> How can I set my group id different from what the passwd file returns?
>The real solution is to change both the clients and servers so that
>something substantial is passed in the "authentication" field.  I think
>that Sun plans this in the next version of RPC.
>
	I accomplished this task by hacking up the 'r_pcnfsd.c' that came
with PC-NFS. Unfortunately, I can't seem to locate it right now, but the
skinny on it is:
	The authentication procedure was altered to accept a username
followed by a backslash followed by a group, and then to look up the
name (after password checking) in the group database, and return ok
if the person had access for that group. On the PC side, it worked like
this:
	NET NAME name\30 mypassword

	which would log 'name' in with the GID set to 30. The hack included
checking for name and group by either number or text, because it turns out
that PC-NFS only sends 8 characters for a username. So the following syntaxes
would all be correct for name == "mike" == UID 20 :
	NET NAME MIKE *			#login with default group
	NET NAME 20\20 *		#login with group 20
	NET NAME MIKE\BIN *		#login with group bin
	NET NAME MIKE\20 *		#login with group 20
	NET NAME 20\STAFF *		#login with group staff
	NET NAME MIKE\STAFF *		#won't work, more than 8 chars

	All of this is easily accomplished with a little knowledge of the
system uid and gid functions. This solved our immediate problem, and didn't
require any changes to the PC software, only the authentication daemon,
(for which source is supplied). I have been told by very reliable sources
that support for multiple groups will be built in to the next version
of PC-NFS, so I would avoid doing this, if it can wait another month or two...

------------------------------------------------------------------------
	
 m     m     k              Mike Macgirvin
 m m m m  o  k  k   eee     Stanford Relativity Gyro Experiment
 m  m  m     k k   e   e    Stanford University
 m     m  i  kk    eeeee        (415) 725-4117
 m     m  i  k k   e        ARPA: mike@relgyro.stanford.edu (36.64.0.50)
 m     m  i  k  k   eeee    UUCP: /dev/null

	This room has been punched out.
		Now where are all the gazingas?

guy@auspex.auspex.com (Guy Harris) (04/23/89)

>The real solution is to change both the clients and servers so that
>something substantial is passed in the "authentication" field.  I think
>that Sun plans this in the next version of RPC.

"Next version"?  The version that came out with SunOS 4.0, and the
NFSSRC 4.0 ONC/NFS distribution, already includes this, if you're
referring to "DES authentication".  I don't know if it's in the 3.9
version of RPC posted to "comp.sources.unix".

More correctly, I don't know whether *most* of it is there; assorted
bureaucrats in the US government have decided that encryption mechanisms
are "munitions", and therefore the encryption code used in DES
authentication requires all sorts of obnoxious export licenses, at least
in source form.  As such, I doubt the 3.9 version has the encryption
code, and I suspect 4.0 source and the NFSSRC 4.0 distribution has
"domestic" and "international" versions, with the latter not including
the DES code.

sxn%ingersoll@Sun.COM (Stephen X. Nahm) (04/24/89)

In article <1489@auspex.auspex.com> guy@auspex.auspex.com (Guy Harris) writes:
>"Next version"?  The version that came out with SunOS 4.0, and the
>NFSSRC 4.0 ONC/NFS distribution, already includes this, if you're
>referring to "DES authentication".  I don't know if it's in the 3.9
>version of RPC posted to "comp.sources.unix".

RPCSRC 3.9 was based on SunOS 4.0 Beta code; the DES stuff was removed since it
hadn't been completely tested yet.

RPCSRC 4.0 does have Secure RPC included with it; however the DES encryption
routine was removed due to export restrictions.

Incidentally, I sent RPCSRC 4.0 to sun-spots for inclusion in its archives, but
this hasn't happened yet.  But you can find it sitting in the "incoming"
directory on titan.rice.edu if you have FTP access.  In that directory you'll
find:

    rpc_40.01 thru rpc_40.17            RPCSRC, less Secure RPC
    rpc_39-40.01 thru rpc_39-40.03      "patch" files to upgrade RPCSRC 3.9
                                        to RPCSRC 4.0, less Secure RPC
    secure_rpc.01 thru secure_rpc.04    Secure RPC, less DES code

Steve Nahm                              sxn@sun.COM or sun!sxn

geoff@hinode.east.sun.com (Geoff Arnold @ Sun ECD - R.H. coast near the top) (04/26/89)

In article <462@sequoia.UUCP> teb@sequoia.UUCP () writes:
>How can I set my group id different from what the passwd file returns?
>The 'net name' command returns me with a group id but I belong to other
>groups (in yp database group). How can I set my group id for access to
>these other groups?

In the next release of PC-NFS the "net name XXX" command will consult
the "group" YP map for additional group membership. Stay tuned for
the formal announcement on comp.newprod.

Geoff

Geoff Arnold,                              Internet: garnold@sun.com
Manager, PC-NFS Engineering                UUCP: ....!sun!garnold
PCDS Group, Sun Microsystems Inc.
"A disclaimer? Sure, at that price you can have half a dozen of 'em."