docs/132260: dhcpd(8) pid not stored in documented location

[Daniel Feenberg]

The following reply was made to PR docs/132260; it has been noted by GNATS.

From: Daniel Feenberg <feenberg at nber.org>
To: Josh Paetzel <jpaetzel at FreeBSD.org>
Cc: bug-followup at FreeBSD.org, Giorgos Keramidas <keramida at FreeBSD.org>
Subject: Re: docs/132260: dhcpd(8) pid not stored in documented location
Date: Thu, 22 Oct 2009 18:37:13 -0400 (EDT)

 I think I will drop out of this discussion now, as it seems likely to go 
 over my head, and we are upgrading to 8.0 next month, and I never meant to 
 make trouble. If paranoia was the default, then I expect it was set for 
 our installation - I wasn't aware of that. I thought there was a minor 
 documentation slip, and thought it would be useful to file a report. I am 
 not qualified to do much more than that, although I do wonder at the 
 desirability of accepting patches to the code without requiring equivalent 
 patches to the documentation.
 
 Sorry for butting in on matters I don't understand.
 
 Daniel Feenberg
 
 On Thu, 22 Oct 2009, Josh Paetzel wrote:
 
 >
 > On Oct 22, 2009, at 1:43 PM, Daniel Feenberg wrote:
 >
 >> 
 >> 
 >> On Thu, 22 Oct 2009, Josh Paetzel wrote:
 >> 
 >>> The reason that it puts the pidfile in /var/run/dhcpd is that you are 
 >>> running with either paranoia or chmodded as the dhcpd user.  In either 
 >>> case it can't write to /var/run as it starts up as the dhcpd user.
 >> 
 >> If you say so.
 >> 
 >>> 
 >>> If you look at the ownership of /var/run/dhcpd you'll see it is owned by 
 >>> dhcpd:dhcpd
 >> 
 >> Yes
 >> 
 >>> 
 >>> If you run as root, or without paranoia it will in fact create the pidfile 
 >>> in /var/run/
 >> 
 >> I do run dhcpd as root and without paranoia, so I question this claim. If 
 >> the daemon changes its uid for security purposes, I have no objection 
 >> (although there is no mention of this on the man page) but why not fill in 
 >> /var/run as documented before dropping priviledges?
 >> 
 >
 >> ls -lah /var/run/dhcpd.pid
 > -rw-r--r--  1 root  wheel     6B Oct 22 12:18 /var/run/dhcpd.pid
 >
 > The FreeBSD version of ISC-DHCP is heavily patched.   The man page is 
 > straight from ISC, so it doesn't cover a lot of things, for instance the 
 > mangling that is done to run in a jail.  I haven't had a chance to fully 
 > analyze the startup script (which is also FreeBSD specific of course)  I 
 > suspect that the reason /var/run/dhcpd.pid isn't always used is there is code 
 > being shared that concerns the chroot option.  It could be that the use case 
 > you are encountering is a bug, maybe it should be writing to 
 > /var/run/dhcpd.pid and it isn't by mistake.
 >
 >
 >>> 
 >>> I suppose we could patch the man pages depending on the compilation 
 >>> options or something.
 >>> 
 >> 
 >> No need for anything so elaborate. You could just add a fourth file path to 
 >> the list of files used.
 >> 
 >> Thanks for having a look. It isn't a big deal and I thought I was helping.
 >> 
 >> Daniel Feenberg
 >> 
 >> 
 >
 > Getting the path correct depends on compile time options.  If you select 
 > PARANOIA from the menu when you build this port (which is the default) (or 
 > use the package) it will use /var/run/dhcpd/dhcpd.conf
 >
 > Could you provide me with the output of cat 
 > /var/db/ports/isc-dhcp30-server/options please?  If you are using a package 
 > there won't be an options file.  I'd also be interested in whatever settings 
 > you have in /etc/rc.conf that are relevant to the dhcpd so I can try and 
 > duplicate this locally.
 >
 > Clearly the documentation does not match actual behavior in some instances. 
 > I'd like to fix that, and I appreciate you pointing it out.
 >
 > Thanks,
 >
 > Josh Paetzel
 >
 >
 >