ether_gen_addr9
Generate an arbitrary mac address for use
Usage
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/ethernet.h>
void
ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr);
Overview
The ether_gen_addr() function generates an arbitrary MAC address for use by an ethernet interface that does not have an assigned address.
By default, ether_gen_addr attempts to generate a stable MAC address using the hostid of the jail that the ifp is being added to. During early boot, the hostid may not be set on machines that haven't yet populated /etc/hostid, or on machines that do not use loader(8).
ether_gen_addr can fail to derive a MAC address due to memory allocation failure, or because the hostid has not been populated. In these cases, a locally-administered unicast MAC address will be randomly generated and returned via the hwaddr parameter.
If ether_gen_addr succeeds, then it will return a MAC address in the FreeBSD Foundation OUI, “58:9c:fc”, via the hwaddr parameter.
Releases
16 releases since FreeBSD 12.3-RELEASE; the text changed 1 time.