If there are v4 or v6 specific options we can keep those in separate sections,
but for the common options, we will use only one.
Moreovere only use DHCP=[yes/both|no/none|v4|v6] to enable or disable the clients.
When enabled in [Network] it will set up a dhcp server on the interface, listening
on one of its statically configured IPv4 addresses and with a fixed size pool of
leases determined from it.
Example:
[Match]
Name=ve-arch-tree
[Network]
Address=192.168.12.5/24
DHCPServer=yes
[Route]
Gateway=192.168.12.5
Destination=192.168.12.0/24
In this case we will configure ve-arch-tree with the address 192.168.12.5 and
hand out addresses in the range 192.168.12.6 - 192.168.12.38.
In the future, we should (as suggested by Lennart) introduce a syntax to pick the
server address automatically.
This does not belong in shared as it is mostly a detail of our networking subsystem.
Moreover, now we can use libudev here, which will simplify things.
Implements IPv4LL with respect to RFC 3927
(http://tools.ietf.org/rfc/rfc3927.txt) and integrates it
with networkd. Majority of the IPv4LL state machine is
taken from avahi (http://avahi.org/) project's autoip.
IPv4LL can be enabled by IPv4LL=yes under [Network]
section of .network file.
IPv4LL works independent of DHCP but if DHCP lease is
aquired, then LL address will be dropped.
[tomegun: removed a trailing newline and a compiler warning]
