.\" $OpenBSD: ieee80211.9,v 1.15 2022/03/29 18:15:52 naddy Exp $ .\" .\" Copyright (c) 2004 Bruce M. Simpson .\" Copyright (c) 2004 Darron Broad .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $FreeBSD: src/share/man/man9/ieee80211.9,v 1.3 2004/07/07 12:59:39 ru Exp $ .\" $Id: ieee80211.9,v 1.15 2022/03/29 18:15:52 naddy Exp $ .\" .Dd $Mdocdate: March 29 2022 $ .Dt IEEE80211_IFATTACH 9 .Os .Sh NAME .Nm ieee80211_ifattach , ieee80211_ifdetach , .Nm ieee80211_mhz2ieee , ieee80211_chan2ieee , ieee80211_ieee2mhz , .Nm ieee80211_media_init , ieee80211_media_change , ieee80211_media_status , .Nm ieee80211_watchdog , .Nm ieee80211_setmode , ieee80211_chan2mode , .Nm ieee80211_rate2media , ieee80211_media2rate , .Nm ieee80211_rate2plcp , ieee80211_plcp2rate .Nd core 802.11 network stack functions .Sh SYNOPSIS .In net80211/ieee80211_var.h .In net80211/ieee80211_proto.h .Ft void .Fn ieee80211_ifattach "struct ifnet *ifp" .Ft void .Fn ieee80211_ifdetach "struct ifnet *ifp" .Ft u_int .Fn ieee80211_mhz2ieee "u_int freq" "u_int flags" .Ft u_int .Fn ieee80211_chan2ieee "struct ieee80211com *ic" \ "const struct ieee80211_channel *c" .Ft u_int .Fn ieee80211_ieee2mhz "u_int chan" "u_int flags" .Ft void .Fo ieee80211_media_init .Fa "struct ifnet *ifp" "ifm_change_cb_t media_change" .Fa "ifm_stat_cb_t media_stat" .Fc .Ft int .Fn ieee80211_media_change "struct ifnet *ifp" .Ft void .Fn ieee80211_media_status "struct ifnet *ifp" "struct ifmediareq *imr" .Ft void .Fn ieee80211_watchdog "struct ifnet *ifp" .Ft int .Fn ieee80211_setmode "struct ieee80211com *ic" "enum ieee80211_phymode mode" .Ft enum ieee80211_phymode .Fo ieee80211_chan2mode .Fa "struct ieee80211com *ic" "const struct ieee80211_channel *chan" .Fc .Ft int .Fo ieee80211_rate2media .Fa "struct ieee80211com *ic" "int rate" "enum ieee80211_phymode mode" .Fc .Ft int .Fn ieee80211_media2rate "int mword" .Ft u_int8_t .Fn ieee80211_rate2plcp "u_int8_t rate" "enum ieee80211_phymode mode" .Ft u_int8_t .Fn ieee80211_plcp2rate "u_int8_t plcp" "enum ieee80211_phymode mode" .Sh DESCRIPTION The .Nm 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. .Pp .\" The .Fn ieee80211_ifattach function attaches the network interface .Fa ifp to the 802.11 network stack layer. This function must be called before using any of the .Nm ieee80211 functions which need to store driver state across invocations. The .Vt struct ifnet instance pointed to by .Fa ifp MUST be an instance of .Vt struct ieee80211com , with various fields initialized to tell .Nm ieee80211 about its capabilities. This function performs Ethernet and BPF attachment (by calling .Fn ether_ifattach and .Fn bpfattach ) on behalf of the caller. It also implements the .Vt ifmedia interface. .Pp .\" The .Fn ieee80211_ifdetach function frees any .Nm ieee80211 structures associated with the driver, and performs Ethernet and BPF detachment on behalf of the caller. .Pp .\" The .Fn ieee80211_mhz2ieee utility function converts the frequency .Fa freq (specified in MHz) to an IEEE 802.11 channel number. The .Fa flags argument is a hint which specifies whether the frequency is in the 2GHz ISM band .Pq Vt IEEE80211_CHAN_2GHZ or the 5GHz band .Pq Vt IEEE80211_CHAN_5GHZ ; appropriate clipping of the result is then performed. .Pp .\" The .Fn ieee80211_chan2ieee function converts the channel specified in .Fa *c to an IEEE channel number for the driver .Fa 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 .Nm ieee80211 subsystem. .Pp .\" The .Fn ieee80211_ieee2mhz utility function converts the IEEE channel number .Ft chan to a frequency (in MHz). The .Fa flags argument is a hint which specifies whether the frequency is in the 2GHz ISM band .Pq Vt IEEE80211_CHAN_2GHZ or the 5GHz band .Pq Vt IEEE80211_CHAN_5GHZ ; appropriate clipping of the result is then performed. .Pp .\" The .Fn ieee80211_media_init function initializes media data structures used by the .Vt ifmedia interface, for the driver .Fa ifp . It must be called by the driver after calling .Fn ieee80211_ifattach and before calling most .Nm ieee80211 functions. The .Fa media_change and .Fa media_stat arguments specify helper functions which will be invoked by the .Vt ifmedia framework when the user changes or queries media options, using a command such as .Xr ifconfig 8 . .Pp .\" The .Fn ieee80211_media_status and .Fn ieee80211_media_change functions are device-independent handlers for .Vt ifmedia commands and are not intended to be called directly. .Pp .\" The .Fn ieee80211_watchdog function is intended to be called from a driver's .Va if_watchdog routine. It is used to perform periodic cleanup of state within the software 802.11 stack, as well as timing out scans. .Pp .\" The .Fn 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. .Pp .\" The .Fn ieee80211_chan2mode function returns the PHY mode required for use with the channel .Fa chan on the device .Fa ic . This is typically used when selecting a rate set, to be advertised in beacons, for example. .Pp .\" The .Fn ieee80211_rate2media function converts the bit rate .Fa rate (measured in units of 0.5Mbps) to an .Vt ifmedia sub-type, for the device .Fa ic running in PHY mode .Fa mode . The .Fn ieee80211_media2rate function performs the reverse of this conversion, returning the bit rate (in 0.5Mbps units) corresponding to an .Vt ifmedia sub-type. .Pp .\" The .Fn ieee80211_rate2plcp function converts the bit rate .Fa rate (measured in units of 0.5Mbps) to a .Vt plcp signal (in msb-first R4-R1 format). The .Fn ieee80211_plcp2rate function performs the reverse of this conversion, returning the bit rate (in 0.5Mbps units) corresponding to a .Vt plcp signal (in msb-first R4-R1 format). .\" .Sh SEE ALSO .Xr ifmedia 4 , .Xr ieee80211_crypto 9 , .Xr ieee80211_input 9 , .Xr ieee80211_ioctl 9 , .Xr ieee80211_node 9 , .Xr ieee80211_output 9 , .Xr ieee80211_proto 9 , .Xr ieee80211_radiotap 9 , .Xr rssadapt 9 .Sh HISTORY The .Nm ieee80211 series of functions first appeared in .Nx 1.5 , and were later ported to .Fx 4.6 and .Ox 3.6 . .Sh AUTHORS .An -nosplit This man page was written by .An Bruce M. Simpson Aq Mt bms@FreeBSD.org and .An Darron Broad Aq Mt darron@kewl.org .