privsep: Add support for priviledge separation

Not enabled by default - enable with ./configure --enable-privsep
Requires a user added to the system - default _dhcpcd

Several processes will be spawned off the main state engine:
a privileged actioneer and a generic network proxy.
Only the privileged actioneer process will retain root permissions.

When required, the privileged actioneer will also spawn
BPF listeners for BOOTP (DHCP) and ARP.
The BOOTP BPF listener should be a short lived process.
On kernels with RFC 5227 support, the ARP BPF listener will only
be used for ARPing and announcing a preferred address and will
also be a short lived process.

When not running in master mode, an address listener will be
spawned for each address (with the exception of RA dervived addresses)
dhcpcd cares about.

TODO:
 * Solaris support.
 * ARP BPF address filtering.

1 files changed, 5 insertions, 1 deletions

diff --git a/README.md b/README.md
index f5c40a9f..d5989d35 100644
--- a/README.md
+++ b/README.md
@@ -91,7 +91,11 @@ dhcpcd-7 defaults the database directory to `/var/db/dhcpcd` instead of
 in /etc.
 The Makefile `_confinstall` target will attempt to move the files correctly from
 the old locations to the new locations.
-Of course this won't work if dhcpcd-7 is packaged up, so packagers will need to
+
+dhcpcd-9 defaults the run directory to `/var/run/dhcpcd` instead of
+`/var/run` and the prefix of dhcpcd has been removed from the files.
+
+Of course this won't work if dhcpcd is packaged up, so packagers will need to
 install similar logic into their dhcpcd package.
 
 ## ChangeLog