dhcp: add nettools dhcp4 client

This is inspired by the existing systemd integration, with a few differences:

* This parses the WPAD option, which systemd requested, but did not use.
* We hook into the DAD handling, only making use of the configured address
  once DAD has completed successfully, and declining the lease if it fails.

There are still many areas of possible improvement. In particular, we need
to ensure the parsing of all options are compliant, as n-dhcp4 treats all
options as opaque, unlike sd-dhcp4. We probably also need to look at how
to handle failures and retries (in particular if we decline a lease).

We need to query the current MTU at client startu, as well as the hardware
broadcast address. Both these are provided by the kernel over netlink, so
it should simply be a matter of hooking that up with NM's netlink layer.

Contribution under LGPL2.0+, in addition to stated licenses.

1 files changed, 1 insertions, 1 deletions

diff --git a/contrib/scripts/checkpatch.pl b/contrib/scripts/checkpatch.pl
index f50b37d413..b5af6dfc2f 100755
--- a/contrib/scripts/checkpatch.pl
+++ b/contrib/scripts/checkpatch.pl
@@ -181,7 +181,7 @@ next if $filename =~ /\/nm-[^\/]+-enum-types\.[ch]$/;
 next if $filename =~ /\bsrc\/systemd\//
 	and not $filename =~ /\/sd-adapt\//
 	and not $filename =~ /\/nm-/;
-next if $filename =~ /\/(n-acd|c-list|c-siphash)\//;
+next if $filename =~ /\/(n-acd|c-list|c-siphash|n-dhcp4)\//;
 
 complain ('Tabs are only allowed at the beginning of a line') if $line =~ /[^\t]\t/;
 complain ('Trailing whitespace') if $line =~ /[ \t]$/;