Re: [gpsd-dev] Updated docs on NTP segment management

[Gary E. Miller]

Yo Hal!

On Tue, 17 Feb 2015 12:47:37 -0800
Hal Murray <address@hidden> wrote:

> 
> > Yes, but I have been pushing Harlan and Pearly to all ntpshm
> > segments can be group ntpd and perms 660.  We should coordinate
> > this with them. This swamp could be mostly drained if we do it
> > together. 
> 
> Please don't spend a lot of time trying to drain the old swamp.

I don't think it will take much time if we just convert to perms
660.  ntpshm is pretty close to being pretty damn good.

> We can replace it with a new scheme that is read only to clients.

Yes, there are cool new things to do, but ntpshm is very lightweight,
thus embedded friendly.  Plus, I assume, a large legacy usage.

> Does that solve the protection issues?

An interesting idea.  You are suggesting perms 640 or 644?  If
ntpd runs as ntpd:ntpd and creates the ntpshm as 640, then how
does gpsd which runs as gpsd:ntpd write to it?

I would hate to enforce that ntpd never create the ntpshm, or that
ntpd and gpsd run as the same user.

> Is there any reason to make gpsd's SHM not world readable?

Not that I can think of, but worth asking around.  Seems to me
local time is not exactly a secret.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701
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