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...

struct	neighbour_delay
	A neighbour transmission delay pseudo-header. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)

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)
	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_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
	)

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

Return values

rc	Return status code

Definition at line 367 of file neighbour.c.

                                             {
         struct neighbour *neighbour;
         struct neighbour_delay *delay;
         int rc;
 
         /* 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 discovery is still in progress or if delay injection is
          * in use, then queue for later transmission.
          */
         if ( NEIGHBOUR_DELAY_MS || neighbour->discovery ) {
 
                 /* Add to deferred packet queue */
                 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 );
 
                 /* Handle delay injection, if applicable */
                 if ( NEIGHBOUR_DELAY_MS ) {
 
                         /* Record original transmission time */
                         delay = iob_push ( iobuf, sizeof ( *delay ) );
                         delay->start = currticks();
 
                         /* Process deferred packet queue, if possible */
                         if ( ! neighbour->discovery )
                                 neighbour_tx_queue ( neighbour );
                 }
 
                 return 0;
         }
 
         /* Otherwise, transmit immediately */
         if ( ( rc = net_tx ( iobuf, netdev, net_protocol, neighbour->ll_dest,
                              netdev->ll_addr ) ) != 0 ) {
                 return rc;
         }
 
         return 0;
 }

References currticks(), DBGC2, delay, neighbour::discovery, ENOMEM, iob_push, io_buffer::list, list_add_tail, net_device::ll_addr, neighbour::ll_dest, net_protocol::name, net_device::name, neighbour_create(), NEIGHBOUR_DELAY_MS, neighbour_discover(), neighbour_find(), neighbour_tx_queue(), net_tx(), netdev, net_protocol::ntoa, rc, 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 428 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 453 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;
 }