Import dhcpcd(8) into FreeBSD base.
This exists in parallel with dhclient(8), which continues to be the
default DHCP client. This can be changed by setting dhcp_client="dhcpcd"
into /etc/rc.conf.
Once set as the default, dhcpcd(8) can be used in 2 different modes:
1. Master mode - by setting dhcpcd_enable="YES" in /etc/rc.conf.
This will enabled dhcpcd(8) for all network interfaces (except those
that cannot utilise DHCP - such as firewire, tap and bridge).
By default, dhcpcd(8) will try to configure DHCPv4 and DHCPv6.
Consider modifying dhcpcd.conf(5) to further configure per interface
settings in this mode.
2. Interface mode - by setting the following parameters in /etc/rc.conf:
ifconfig_em0="DHCP"
ifconfig_em0_ipv6="DHCP"
Setting these will enable DHCPv4 and DHCPv6 respectively on the
specified interface. These can be set independently of each other.
dhcpcd_enable should not be set in this mode (it defaults to "NO").