Manual browser: ETHER_IS_MULTICAST(9)

ETHERSUBR(9) Kernel Developer's Manual ETHERSUBR(9)


ethersubr, ether_ifattach, ether_addmulti, ether_delmulti, ETHER_FIRST_MULTI, ETHER_NEXT_MULTI, ETHER_IS_MULTICAST, fddi_ifattach, fddi_addmulti, fddi_delmultiEthernet and FDDI driver support functions and macros


#include <net/if_ether.h>

ether_ifattach(struct ifnet *ifp, uint8_t *lla);

ether_addmulti(const struct sockaddr *sa, struct ethercom *ec);

ether_delmulti(const struct sockaddr *sa, struct ethercom *ec);

ETHER_FIRST_MULTI(struct ether_multistep step, struct ethercom *ec, struct ether_multi *enm);

ETHER_NEXT_MULTI(struct ether_multistep step, struct ether_multi *enm);

ETHER_IS_MULTICAST(uint8_t *addr);

#include <net/if_fddi.h>

fddi_ifattach(struct ifnet *ifp, uint8_t *lla);

fddi_addmulti(const struct sockaddr *sa, struct ethercom *ec);

fddi_delmulti(const struct sockaddr *sa, struct ethercom *ec);


The ethersubr functions provide the interface between the ethersubr module and the network drivers which need Ethernet support. Such drivers must request the ether attribute in their files declaration and call the appropriate functions as specified below.

FDDI drivers must request the "fddi" attribute in their "files" declaration and call the functions tagged with "fddi_" or "FDDI_" instead, where different. Some macros are shared.

Note that you also need the arp(9) stuff to support IPv4 on your hardware.

ether_ifattach(ifp, lla)
Perform the device-independent, but Ethernet-specific initialization of the interface pointed to by ifp.

Among other duties, this function creates a record for the link level address in the interface's address list and records the link level address pointed to by lla there.

This function must be called from the driver's attach function.

fddi_ifattach(ifp, lla)
Corresponding function for FDDI devices.
ether_addmulti(sa, ec)
ether_delmulti(sa, ec)
Add (ether_addmulti()) or delete (ether_delmulti()) the address described by the sa pointer to the Ethernet multicast list belonging to ec.

These functions must be called from the driver's ioctl function to handle SIOCADDMULTI and SIOCDELMULTI requests. If these return ENETRESET, the hardware multicast filter must be reinitialized.

These functions accept AF_UNSPEC addresses, which are interpreted as Ethernet addresses, or AF_INET addresses. In the latter case, INADDR_ANY is mapped to a range describing all the Ethernet address space reserved for IPv4 multicast addresses.

The ether_addmulti() returns EAFNOSUPPORT if an unsupported address family is specified, EINVAL if a non-multicast address is specified, or ENETRESET if the multicast list really changed and the driver should synchronize its hardware filter with it.

The ether_delmulti() returns, in addition to the above errors, ENXIO if the specified address can't be found in the list of multicast addresses.

fddi_addmulti(sa, ec)
fddi_delmulti(sa, ec)
Corresponding functions for FDDI devices.
A macro to step through all of the ether_multi records, one at a time. The current position is remembered in step, which the caller must provide.
ETHER_FIRST_MULTI(step, ec, enm)
A macro that must be called to initialize step and get the first record. Both macros return a NULL enm when there are no remaining records.
A macro that returns 1, if addr points to an Ethernet/FDDI multicast (or broadcast) address.


Ethernet support functions are declared in <net/if_ether.h> and defined (if not implemented as macro) in sys/net/if_ethersubr.c.

FDDI support functions are declared in <net/if_fddi.h> and defined (if not implemented as macro) in sys/net/if_fddisubr.c.




Rewritten to attach to the new ARP system in NetBSD 1.3.


UCB CSRG (original implementation)

Ignatios Souvatzis (support for new ARP system)

March 3, 1997 NetBSD 7.0