NAME
ieee80211_ifattach
,
ieee80211_ifdetach
,
ieee80211_mhz2ieee
,
ieee80211_chan2ieee
,
ieee80211_ieee2mhz
,
ieee80211_media_init
,
ieee80211_media_change
,
ieee80211_media_status
,
ieee80211_watchdog
,
ieee80211_setmode
,
ieee80211_chan2mode
,
ieee80211_rate2media
,
ieee80211_media2rate
,
ieee80211_rate2plcp
,
ieee80211_plcp2rate
—
core 802.11 network stack
functions
SYNOPSIS
#include
<net80211/ieee80211_var.h>
#include
<net80211/ieee80211_proto.h>
void
ieee80211_ifattach
(struct
ifnet *ifp);
void
ieee80211_ifdetach
(struct
ifnet *ifp);
u_int
ieee80211_mhz2ieee
(u_int
freq, u_int
flags);
u_int
ieee80211_chan2ieee
(struct
ieee80211com *ic, const
struct ieee80211_channel *c);
u_int
ieee80211_ieee2mhz
(u_int
chan, u_int
flags);
void
ieee80211_media_init
(struct ifnet
*ifp, ifm_change_cb_t media_change,
ifm_stat_cb_t media_stat); int
ieee80211_media_change
(struct
ifnet *ifp); void
ieee80211_media_status
(struct
ifnet *ifp, struct
ifmediareq *imr);
void
ieee80211_watchdog
(struct
ifnet *ifp);
int
ieee80211_setmode
(struct
ieee80211com *ic, enum
ieee80211_phymode mode);
enum ieee80211_phymode
ieee80211_chan2mode
(struct
ieee80211com *ic, const struct ieee80211_channel
*chan);
int
ieee80211_rate2media
(struct
ieee80211com *ic, int rate, enum
ieee80211_phymode mode);
int
ieee80211_media2rate
(int
mword);
u_int8_t
ieee80211_rate2plcp
(u_int8_t
rate, enum
ieee80211_phymode mode);
u_int8_t
ieee80211_plcp2rate
(u_int8_t
plcp, enum
ieee80211_phymode mode);
DESCRIPTION
The ieee80211
collection of functions are
used to manage wireless network interfaces in the system which use the
system's software 802.11 network stack. Most of these functions require that
attachment to the stack is performed before calling. Several utility
functions are also provided; these are safe to call from any driver without
prior initialization.
The
ieee80211_ifattach
()
function attaches the network interface ifp to the
802.11 network stack layer. This function must be called before using any of
the ieee80211
functions which need to store driver
state across invocations. The struct ifnet instance
pointed to by ifp MUST be an instance of
struct ieee80211com, with various fields initialized
to tell ieee80211
about its capabilities. This
function performs Ethernet and BPF attachment (by calling
ether_ifattach
()
and
bpfattach
())
on behalf of the caller. It also implements the
ifmedia interface.
The
ieee80211_ifdetach
()
function frees any ieee80211
structures associated
with the driver, and performs Ethernet and BPF detachment on behalf of the
caller.
The
ieee80211_mhz2ieee
()
utility function converts the frequency freq
(specified in MHz) to an IEEE 802.11 channel number. The
flags argument is a hint which specifies whether the
frequency is in the 2GHz ISM band
(IEEE80211_CHAN_2GHZ) or the 5GHz band
(IEEE80211_CHAN_5GHZ); appropriate clipping of the
result is then performed.
The
ieee80211_chan2ieee
()
function converts the channel specified in *c to an
IEEE channel number for the driver ic. If the
conversion would be invalid, an error message is printed to the system
console. This function requires that the driver is hooked up to the
ieee80211
subsystem.
The
ieee80211_ieee2mhz
()
utility function converts the IEEE channel number chan
to a frequency (in MHz). The flags argument is a hint
which specifies whether the frequency is in the 2GHz ISM band
(IEEE80211_CHAN_2GHZ) or the 5GHz band
(IEEE80211_CHAN_5GHZ); appropriate clipping of the
result is then performed.
The
ieee80211_media_init
()
function initializes media data structures used by the
ifmedia interface, for the driver
ifp. It must be called by the driver after calling
ieee80211_ifattach
() and before calling most
ieee80211
functions. The
media_change and media_stat
arguments specify helper functions which will be invoked by the
ifmedia framework when the user changes or queries
media options, using a command such as
ifconfig(8).
The
ieee80211_media_status
()
and
ieee80211_media_change
()
functions are device-independent handlers for ifmedia
commands and are not intended to be called directly.
The
ieee80211_watchdog
()
function is intended to be called from a driver's
if_watchdog routine. It is used to perform periodic
cleanup of state within the software 802.11 stack, as well as timing out
scans.
The
ieee80211_setmode
()
function is called from within the 802.11 stack to change the mode of the
driver's PHY; it is not intended to be called directly.
The
ieee80211_chan2mode
()
function returns the PHY mode required for use with the channel
chan on the device ic. This is
typically used when selecting a rate set, to be advertised in beacons, for
example.
The
ieee80211_rate2media
()
function converts the bit rate rate (measured in units
of 0.5Mbps) to an ifmedia sub-type, for the device
ic running in PHY mode mode. The
ieee80211_media2rate
()
performs the reverse of this conversion, returning the bit rate (in 0.5Mbps
units) corresponding to an ifmedia sub-type.
The
ieee80211_rate2plcp
()
function converts the bit rate rate (measured in units
of 0.5Mbps) to a plcp signal (in msb-first R4-R1
format). The
ieee80211_plcp2rate
()
function performs the reverse of this conversion, returning the bit rate (in
0.5Mbps units) corresponding to a plcp signal (in
msb-first R4-R1 format).
SEE ALSO
ifmedia(4), ieee80211_crypto(9), ieee80211_input(9), ieee80211_ioctl(9), ieee80211_node(9), ieee80211_output(9), ieee80211_proto(9), ieee80211_radiotap(9), rssadapt(9)
HISTORY
The ieee80211
series of functions first
appeared in NetBSD 1.5, and were later ported to
FreeBSD 4.6 and OpenBSD
3.6.
AUTHORS
This man page was written by Bruce M. Simpson ⟨bms@FreeBSD.org⟩ and Darron Broad ⟨darron@kewl.org⟩.