IEEE80211_NODE(9) | Kernel Developer's Manual | IEEE80211_NODE(9)

# NAME

`ieee80211_node_attach`, `ieee80211_node_lateattach`, `ieee80211_node_detach`, `ieee80211_begin_scan`, `ieee80211_next_scan`, `ieee80211_end_scan`, `ieee80211_create_ibss`, `ieee80211_alloc_node`, `ieee80211_dup_bss`, `ieee80211_find_node`, `ieee80211_free_node`, `ieee80211_free_allnodes`, `ieee80211_iterate_nodes` —
software 802.11 stack node management functions

# SYNOPSIS

`#include <net80211/ieee80211_var.h>`
`#include <net80211/ieee80211_proto.h>`
`#include <net80211/ieee80211_node.h>`

void
`ieee80211_node_attach`(struct ieee80211com *ic);

void
`ieee80211_node_lateattach`(struct ieee80211com *ic);

void
`ieee80211_node_detach`(struct ieee80211com *ic);

void
`ieee80211_begin_scan`(struct ieee80211com *ic, int reset);

void
`ieee80211_next_scan`(struct ieee80211com *ic);

void
`ieee80211_end_scan`(struct ieee80211com *ic);

void
`ieee80211_create_ibss`(struct ieee80211com *ic, struct ieee80211_channel *chan);

struct ieee80211_node *
`ieee80211_alloc_node`(struct ieee80211com *ic, u_int8_t *macaddr);

struct ieee80211_node *
`ieee80211_dup_bss`(struct ieee80211_node_table *nt, const u_int8_t *macaddr);

struct ieee80211_node *
`ieee80211_find_node`(struct ieee80211_node_table *nt, const u_int8_t *macaddr);

void
`ieee80211_free_node`(struct ieee80211_node *ni);

void
`ieee80211_free_allnodes`(struct ieee80211_node_table *nt);

void
`ieee80211_iterate_nodes`(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg);

# DESCRIPTION

These functions are used to manage node lists within the software 802.11 stack. These lists are typically used for implementing host-mode AP functionality, or providing signal quality information about neighbouring nodes.

The `ieee80211_node_attach`() function is called from ieee80211_ifattach(9) to initialize node database management callbacks for the interface ic (specifically for memory allocation, node copying and node signal inspection). These functions may be overridden in special circumstances, as long as this is done after calling ieee80211_ifattach(9) and prior to any other call which may allocate a node.

The `ieee80211_node_lateattach`() function initialises the ic_bss node element of the interface ic during ieee80211_media_init(9). This late attachment is to account for certain special cases described under `ieee80211_node_attach`().

The `ieee80211_node_detach`() function destroys all node database state associated with the interface ic, and is usually called during device detach.

The `ieee80211_begin_scan`() function initialises the node database in preparation of a scan for an access point on the interface ic and begins the scan. The parameter reset controls if a previously built node list should be cleared. The actual scanning for an access point is not fully automated: the device driver itself controls stepping through the channels, usually by a periodical callback.

The `ieee80211_next_scan`() function is used to inform the ieee80211(9) layer that the next channel for interface ic should be scanned.

The `ieee80211_create_ibss`() function sets up the net80211-specific portion of an interface's softc, ic, for use in IBSS mode.

The `ieee80211_end_scan`() function is called by `ieee80211_next_scan`() when the state machine has performed a full cycle of scanning on all available radio channels. Internally, `ieee80211_end_scan`() will inspect the node cache associated with the interface ic for suitable access points found during scanning, and associate with one, should the parameters of the node match those of the configuration requested.

The `ieee80211_alloc_node`() function allocates an instance of struct ieee80211_node for a node having the MAC address macaddr, and associates it with the node table nt. If the allocation is successful, the node structure is initialised by `ieee80211_setup_node`(); otherwise, `NULL` is returned.

The `ieee80211_dup_bss`() function is similar to `ieee80211_alloc_node`(), but is instead used to create a node database entry for the BSSID macaddr associated with the note table nt. If the allocation is successful, the node structure is initialised by `ieee80211_setup_node`(); otherwise, `NULL` is returned.

The `ieee80211_find_node`() function will iterate through the node table nt, searching for a node entry which matches macaddr. If the entry is found, its reference count is incremented, and a pointer to the node is returned; otherwise, `NULL` is returned.

The `ieee80211_free_allnodes`() function will iterate through the node list calling `ieee80211_free_node`() for all the nodes in table nt.

The `ieee80211_iterate_nodes`() function will call the user-defined callback function f for all nodes in the table nt. The callback is invoked with the with the user-supplied value arg and a pointer to the current node.

# SEE ALSO

ieee80211(9)

# HISTORY

The `ieee80211` series of functions first appeared in NetBSD 1.5, and were later ported to FreeBSD 4.6.

# AUTHORS

This man page was written by Bruce M. Simpson <bms@FreeBSD.org> and Darron Broad <darron@kewl.org>.

September 12, 2006 | NetBSD 9.2