1.\" 2.\" Copyright (c) 2009 Sam Leffler, Errno Consulting 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd August 4, 2009 29.Dt IEEE80211_REGDOMAIN 9 30.Os 31.Sh NAME 32.Nm ieee80211_regdomain 33.Nd 802.11 regulatory support 34.Sh SYNOPSIS 35.In net80211/ieee80211_var.h 36.In net80211/ieee80211_regdomain.h 37.Pp 38.Ft int 39.Fo ieee80211_init_channels 40.Fa "struct ieee80211com *" 41.Fa "const struct ieee80211_regdomain *" 42.Fa "const uint8_t bands[]" 43.Fc 44.\" 45.Ft void 46.Fo ieee80211_sort_channels 47.Fa "struct ieee80211_channel *" 48.Fa "int nchans" 49.Fc 50.\" 51.Ft "struct ieee80211_appie *" 52.Fn ieee80211_alloc_countryie "struct ieee80211com *" 53.Sh DESCRIPTION 54The 55.Nm net80211 56software layer provides a support framework for drivers that includes 57comprehensive regulatory support. 58.Nm net80211 59provides mechanisms that enforce 60.Em "regulatory policy" 61by privileged user applications. 62.Pp 63Drivers define a device's capabilities and can 64intercept and control regulatory changes requested through 65.Nm net80211 . 66The initial regulatory state, including the channel list, must be 67filled in by the driver before calling 68.Fn ieee80211_ifattach . 69The channel list should reflect the set of channels the device is 70.Em calibrated 71for use on. 72This list may also be requested later through the 73.Vt ic_getradiocaps 74method in the 75.Vt ieee80211com 76structure. 77The 78.Fn ieee80211_init_channels 79function is provided as a rudimentary fallback for drivers that do not 80(or cannot) fill in a proper channel list. 81Default regulatory state is supplied such as the regulatory SKU, 82ISO country code, location (e.g. indoor, outdoor), and a set of 83frequency bands the device is capable of operating on. 84.Nm net80211 85populates the channel table in 86.Vt ic_channels 87with a default set of channels and capabilities. 88Note this mechanism should be used with care as any mismatch between 89the channel list created and the device's capabilities can result 90in runtime errors (e.g. a request to operate on a channel the device 91does not support). 92The SKU and country information are used for generating 802.11h protocol 93elements and related operation such as for 802.11d; mis-setup by a 94driver is not fatal, only potentially confusing. 95.Pp 96Devices that do not have a fixed/default regulatory state can set 97the regulatory SKU to 98.Dv SKU_DEBUG 99and country code to 100.Dv CTRY_DEFAULT 101and leave proper setup to user applications. 102If default settings are known they can be installed and/or an event 103can be dispatched to user space using 104.Fn ieee80211_notify_country 105so that 106.Xr devd 8 107will do the appropriate setup work at system boot (or device insertion). 108.Pp 109The channel table is sorted to optimize lookups using the 110.Fn ieee80211_sort_channels 111routine. 112This should be done whenever the channel table contents are modified. 113.Pp 114The 115.Fn ieee80211_alloc_countrie 116function allocates an information element as specified by 802.11h. 117Because this is expensive to generate it is cached in 118.Vt ic_countryie 119and generated only when regulatory state changes. 120Drivers that call 121.Fn ieee80211_alloc_countryie 122directly should not help with this caching; doing so may confuse the 123.Nm net80211 124layer. 125.Sh DRIVER REGULATORY CONTROL 126Drivers can control regulatory change requests by overriding the 127.Vt ic_setregdomain 128method that checks change requests. 129While drivers can reject any request that does not meet its requirements 130it is recommended that one be lenient in what is accepted and, whenever 131possible, instead of rejecting a request, alter it to be correct. 132For example, if the transmit power cap for a channel is too high the 133driver can either reject the request or (better) reduce the cap to be 134compliant. 135Requests that include unacceptable channels should cause the request 136to be rejected as otherwise a mismatch may be created between application 137state and the state managed by 138.Nm net80211 . 139The exact rules by which to operate are still being codified. 140.Sh SEE ALSO 141.Xr regdomain 5 , 142.Xr ifconfig 8 , 143.Xr ieee80211 9 . 144