xref: /openbsd/share/man/man4/bwi.4 (revision e5dd7070)
1.\" $OpenBSD: bwi.4,v 1.44 2020/07/02 13:59:32 mglocker Exp $
2.\"
3.\" Copyright (c) 2007 Marcus Glocker <mglocker@openbsd.org>
4.\"
5.\" Permission to use, copy, modify, and distribute this software for any
6.\" purpose with or without fee is hereby granted, provided that the above
7.\" copyright notice and this permission notice appear in all copies.
8.\"
9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16.\"
17.Dd $Mdocdate: July 2 2020 $
18.Dt BWI 4
19.Os
20.Sh NAME
21.Nm bwi
22.Nd Broadcom AirForce IEEE 802.11b/g wireless network device
23.Sh SYNOPSIS
24.Cd "bwi* at cardbus?"
25.Cd "bwi* at pci?"
26.Sh DESCRIPTION
27The
28.Nm
29driver provides support for Broadcom AirForce based
30PCI/Cardbus network adapters.
31.Pp
32These are the modes the
33.Nm
34driver can operate in:
35.Bl -tag -width "IBSS-masterXX"
36.It BSS mode
37Also known as
38.Em infrastructure
39mode, this is used when associating with an access point, through
40which all traffic passes.
41This mode is the default.
42.It monitor mode
43In this mode the driver is able to receive packets without
44associating with an access point.
45This disables the internal receive filter and enables the card to
46capture packets from networks which it wouldn't normally have access to,
47or to scan for access points.
48.El
49.Pp
50The
51.Nm
52driver can be configured to use
53Wired Equivalent Privacy (WEP) or
54Wi-Fi Protected Access (WPA1 and WPA2).
55WPA2 is the current encryption standard for wireless networks.
56It is strongly recommended that neither WEP nor WPA1
57are used as the sole mechanism to secure wireless communication,
58due to serious weaknesses.
59WPA1 is disabled by default and may be enabled using the option
60.Qq Cm wpaprotos Ar wpa1,wpa2 .
61For standard WPA networks which use pre-shared keys (PSK),
62keys are configured using the
63.Qq Cm wpakey
64option.
65WPA-Enterprise networks require use of the wpa_supplicant package.
66The
67.Nm
68driver relies on the software 802.11 stack for both encryption and decryption
69of data frames.
70.Pp
71The transmit speed is user-selectable or can be adapted automatically by the
72driver depending on the received signal strength and on the number of hardware
73transmission retries.
74.Pp
75The
76.Nm
77driver can be configured at runtime with
78.Xr ifconfig 8
79or on boot with
80.Xr hostname.if 5 .
81.Sh FILES
82The driver needs a firmware file which is loaded when an interface is
83brought up:
84.Pp
85.Bl -tag -width Ds -offset indent -compact
86.It Pa /etc/firmware/bwi-airforce
87.El
88.\".Pp
89.\"These firmware files are not free because Broadcom refuses
90.\"to grant distribution rights.
91.\"As a result, even though
92.\".Ox
93.\"includes the driver, the firmware files cannot be included and
94.\"users have to download these files on their own.
95.Pp
96A prepackaged version of the firmware can be installed using
97.Xr fw_update 1 .
98.Sh HARDWARE
99The following cards are among those supported by the
100.Nm
101driver:
102.Bl -column "TRENDnet TEW-401PCplus" "BCM4306" "CardBus" "Standard" -offset 6n
103.It Em Card Ta Em Chip Ta Em Bus Ta Em Standard
104.It "Apple Airport Extreme" Ta BCM4306 Ta PCI Ta b/g
105.It "Apple Airport Extreme" Ta BCM4318 Ta PCI Ta b/g
106.It "ASUS WL-138g" Ta BCM4318 Ta PCI Ta b/g
107.It "Buffalo WLI-CB-G54" Ta BCM4306 Ta CardBus Ta b/g
108.It "Compaq R4035 onboard" Ta BCM4306 Ta PCI Ta b/g
109.It "HP nx6125" Ta BCM4319 Ta PCI Ta b/g
110.It "Linksys WPC54G Ver 3" Ta BCM4318 Ta CardBus Ta b/g
111.It "Linksys WPC54GS Ver 2" Ta BCM4318 Ta CardBus Ta b/g
112.It "TRENDnet TEW-401PCplus" Ta BCM4306 Ta CardBus Ta b/g
113.It "US Robotics 5411" Ta BCM4318 Ta CardBus Ta b/g
114.El
115.Sh EXAMPLES
116The following example scans for available networks:
117.Pp
118.Dl # ifconfig bwi0 scan
119.Pp
120The following
121.Xr hostname.if 5
122example configures bwi0 to join network
123.Dq mynwid ,
124using WPA key
125.Dq mywpakey ,
126obtaining an IP address using DHCP:
127.Bd -literal -offset indent
128nwid mynwid wpakey mywpakey
129dhcp
130.Ed
131.Sh SEE ALSO
132.Xr arp 4 ,
133.Xr cardbus 4 ,
134.Xr ifmedia 4 ,
135.Xr intro 4 ,
136.Xr netintro 4 ,
137.Xr pci 4 ,
138.Xr hostname.if 5 ,
139.\".Xr hostapd 8 ,
140.Xr ifconfig 8
141.Sh HISTORY
142The
143.Nm
144driver first appeared in
145.Ox 4.3 .
146.Sh AUTHORS
147.An -nosplit
148The
149.Nm
150driver was written for
151.Dx
152by
153.An Sepherosa Ziehau
154and ported to
155.Ox
156by
157.An Jonathan Gray
158and
159.An Marcus Glocker .
160.Sh CAVEATS
161Some chips are incorrectly calibrated due to the lack of documentation,
162which can slow the amount of traffic to the point of being unusable.
163Furthermore this driver only supports firmware version 3.
164.Pp
165The BCM4331 chip isn't supported by this driver but the driver disables
166the chip if detected, since some buggy EFI revisions found in 2011-2012
167Macs leave the chip enabled, causing it to emit spurious interrupts when
168the shared interrupt line is enabled.
169.Pp
170This driver does not support powersave mode.
171