On Thu, 26 Mar 2015 17:43:42 -0500, Dan Williams wrote:

ipvlan currently fails DHCP addressing for two reasons:

1) DHCP offers are typically unicast back to the device's MAC
address, and at the IP layer have a destination IP address
matching the new lease address.  In ipvlan unicast packets
are checked against existing addresses assigned to the ipvlan
interface, so clearly this fails hard because the ipvlan
interface has no IP addresses yet.  Workaround: request
that the server broadcast replies (-B for dhclient), which
don't get checked against the IP address list.

2) Even when that's done, mac_filters only allows the
broadcast MAC address when the interface has >= 1 IPv4
addresses, so double-fail, and the incoming DHCP offer
gets dropped on the floor again.

Instead of doing ugly stuff like watching for outgoing DHCP
requests and adding the broadcast MAC to mac_filters for
a period of time, just always allow the broadcast MAC.  This
lets the ipvlan interface be configured with DHCP in
Layer2 mode as long as as broadcast replies are used.

Signed-off-by: Dan Williams <redacted>

I don't see any better option, either.

Reviewed-by: Jiri Benc <redacted>

-- 
Jiri Benc