Neighbour discovery. More...

#include <stdint.h>
#include <ipxe/refcnt.h>
#include <ipxe/list.h>
#include <ipxe/netdevice.h>
#include <ipxe/retry.h>

Data Structures
struct	neighbour_discovery
	A neighbour discovery protocol. More...

struct	neighbour
	A neighbour cache entry. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)

static int	neighbour_has_ll_dest (struct neighbour *neighbour)
	Test if neighbour cache entry has a valid link-layer address. More...

int	neighbour_tx (struct io_buffer iobuf, struct net_device netdev, struct net_protocol net_protocol, const void net_dest, struct neighbour_discovery discovery, const void net_source, const void *ll_source)
	Transmit packet, determining link-layer address via neighbour discovery. More...

int	neighbour_update (struct net_device netdev, struct net_protocol net_protocol, const void net_dest, const void ll_dest)
	Update existing neighbour cache entry. More...

int	neighbour_define (struct net_device netdev, struct net_protocol net_protocol, const void net_dest, const void ll_dest)
	Define neighbour cache entry. More...

Variables
struct list_head	neighbours
	The neighbour cache. More...

Detailed Description

Neighbour discovery.

Definition in file neighbour.h.

Function Documentation

◆ FILE_LICENCE()

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )

◆ neighbour_has_ll_dest()

static int neighbour_has_ll_dest ( struct neighbour * neighbour )

inlinestatic

Test if neighbour cache entry has a valid link-layer address.

Parameters

neighbour Neighbour cache entry

Return values

has_ll_dest Neighbour cache entry has a valid link-layer address

Definition at line 70 of file neighbour.h.

                                                       {
         return ( ! timer_running ( &neighbour->timer ) );
 }

References neighbour::timer.

Referenced by neighbour_tx(), and nstat().

◆ neighbour_tx()

int neighbour_tx	(	struct io_buffer *	iobuf,
		struct net_device *	netdev,
		struct net_protocol *	net_protocol,
		const void *	net_dest,
		struct neighbour_discovery *	discovery,
		const void *	net_source,
		const void *	ll_source
	)

Transmit packet, determining link-layer address via neighbour discovery.

Parameters

iobuf	I/O buffer
netdev	Network device
discovery	Neighbour discovery protocol
net_protocol	Network-layer protocol
net_dest	Destination network-layer address
net_source	Source network-layer address
ll_source	Source link-layer address

Return values

rc	Return status code

Definition at line 299 of file neighbour.c.

                                                                    {
         struct neighbour *neighbour;
 
         /* Find or create neighbour cache entry */
         neighbour = neighbour_find ( netdev, net_protocol, net_dest );
         if ( ! neighbour ) {
                 neighbour = neighbour_create ( netdev, net_protocol, net_dest );
                 if ( ! neighbour )
                         return -ENOMEM;
                 neighbour_discover ( neighbour, discovery, net_source );
         }
 
         /* If a link-layer address is available then transmit
          * immediately, otherwise queue for later transmission.
          */
         if ( neighbour_has_ll_dest ( neighbour ) ) {
                 return net_tx ( iobuf, netdev, net_protocol, neighbour->ll_dest,
                                 ll_source );
         } else {
                 DBGC2 ( neighbour, "NEIGHBOUR %s %s %s deferring packet\n",
                         netdev->name, net_protocol->name,
                         net_protocol->ntoa ( net_dest ) );
                 list_add_tail ( &iobuf->list, &neighbour->tx_queue );
                 return 0;
         }
 }

References DBGC2, neighbour::discovery, ENOMEM, io_buffer::list, list_add_tail, neighbour::ll_dest, net_protocol::name, net_device::name, neighbour_create(), neighbour_discover(), neighbour_find(), neighbour_has_ll_dest(), neighbour::net_dest, neighbour::net_source, net_tx(), netdev, net_protocol::ntoa, and neighbour::tx_queue.

Referenced by arp_tx(), and ndp_tx().

◆ neighbour_update()

int neighbour_update	(	struct net_device *	netdev,
		struct net_protocol *	net_protocol,
		const void *	net_dest,
		const void *	ll_dest
	)

Update existing neighbour cache entry.

Parameters

netdev	Network device
net_protocol	Network-layer protocol
net_dest	Destination network-layer address
ll_dest	Destination link-layer address

Return values

rc	Return status code

Definition at line 338 of file neighbour.c.

                                                                    {
         struct neighbour *neighbour;
 
         /* Find neighbour cache entry */
         neighbour = neighbour_find ( netdev, net_protocol, net_dest );
         if ( ! neighbour )
                 return -ENOENT;
 
         /* Set destination address */
         neighbour_discovered ( neighbour, ll_dest );
 
         return 0;
 }

References ENOENT, neighbour::ll_dest, neighbour_discovered(), neighbour_find(), neighbour::net_dest, and netdev.

Referenced by arp_rx(), and ndp_rx_neighbour_advertisement_ll_target().

◆ neighbour_define()

int neighbour_define	(	struct net_device *	netdev,
		struct net_protocol *	net_protocol,
		const void *	net_dest,
		const void *	ll_dest
	)

Define neighbour cache entry.

Parameters

netdev	Network device
net_protocol	Network-layer protocol
net_dest	Destination network-layer address
ll_dest	Destination link-layer address, if known

Return values

rc	Return status code

Definition at line 363 of file neighbour.c.

                                                                    {
         struct neighbour *neighbour;
 
         /* Find or create neighbour cache entry */
         neighbour = neighbour_find ( netdev, net_protocol, net_dest );
         if ( ! neighbour ) {
                 neighbour = neighbour_create ( netdev, net_protocol, net_dest );
                 if ( ! neighbour )
                         return -ENOMEM;
         }
 
         /* Set destination address */
         neighbour_discovered ( neighbour, ll_dest );
 
         return 0;
 }