Commit Graph

32 Commits

Author SHA1 Message Date
Adrian Chadd
f7f155fa58 Break out the current 802.11 software scan methods into an indirect table.
In order for drivers to provide an alternate set of scan methods,
these have to finally use an indirection table and all of the calls
in ieee80211_scan.c need to use said table.

For all existing drivers - this is basically a glorified, KBI-breaking
functional no-op.

This is also not the final form - too much functionality is currently
hiding in ieee80211_scan_sw.c that should be in ieee80211_scan.c.
That'll be the target of some follow-up commits.

Note:

* You have to recompile your kernel/drivers after this - the net80211 KBI has
  changed.
* I'm not yet planning on bumping any versioning - I have a few more things
  to shuffle around.

Tested:

* urtwn(4) - STA mode
* Intel 7260 in local repo - overriding the methods and table at
  attach time has the desired effect (ie, all the methods are called,
  but nothing is ever performed.)
2015-06-08 02:35:43 +00:00
Adrian Chadd
2808a02bf4 Prepare for supporting driver-overridden curchan when submitting scan
results.

Right now the scan infrastructure assumes the channel is under net80211
control, and that when receiving beacon frames for scanning, the
current channel is indeed what ic_curchan is set to.

But firmware NICs with firmware scan support need more than this -
they can do background scans whilst hiding the off-channel behaviour
from net80211.  Ie, net80211 still thinks everything is associated
and on the main channel, but it's getting scan results from all the
background traffic.

However sta_add() pays attention to ic_curchan and discards scan
results that aren't on the right channel.  CCK beacon frames can be
decoded from adjacent channels so the receive path and sta_add
discard these as appropriate.  This is fine for software scanning
like for ath(4), but not for firmware NICs.  So with those, the
whole concept of background firmware scanning won't work without
major hacks (eg, overriding ic_curchan before calling the beacon
input / scan add.)

As part of my scan overhaul, modify sta_add() and the scan_add()
APIs to take an explicit current channel.  The normal RX path
will set it to ic_curchan so it's a no-op.  However, drivers may
decide to (eventually!) override the scan method to set the
"right" current channel based on what the firmware reports the
scan state is.

So for example, iwn, rsu and other NICs will eventually do this:

* driver issues scan start firmware command;
* firmware sends a "scan start on channel X" notify;
* firmware sends a bunch of beacon RX's as part of
  the scan results;
* .. and the driver will replace scan_add() curchan with channel X,
  so scan results are correct.
* firmware sends a "scan start on channel Y" notify;
* firmware sends more beacons...
* .. the driver replaces scan_add() curchan with channel Y.

Note:

* Eventually, net80211 should eventually grow the idea of a per-packet
  current channel.  It's possible in various modes (eg WAVE, P2P, etc)
  that individual frames can come in from different channels and that
  is under firmware control rather than driver/net80211 control, so
  we should support that.
2015-05-10 22:07:53 +00:00
Adrian Chadd
bfca9c9400 Turn ieee80211_start_scan_locked() into a swscan module private method.
It turns out that ieee80211_start_scan_locked() is only ever called by
the swscan code and it won't likely be required by firmware scanning
implementations.

So, don't bother keeping it in ieee80211_scan.c and it likely won't
become an API call.

Tested:

* Intel 5100, STA mode
* AR5416, STA mode
2015-05-10 06:59:34 +00:00
Adrian Chadd
a1cbd04334 Global-ify channel_type() - this fixes non-debug net80211 builds. 2015-01-06 18:25:10 +00:00
Adrian Chadd
cc6dd788c6 Refactor and split out the net80211 software scan engine from the rest
of the scan API.

The eventual aim is to have 'ieee80211_scan.c' have the net80211 and
driver facing scan API to start, finish and continue doing scanning
while 'ieee80211_swscan.c' implements the software scanner that
runs the scan task, handles probe request/reply bits, configures
the VAP off-channel, changes channel and does the scanning bits.

For NICs that do no scanning at all, the existing code is needed.
ath(4) and most of the other NICs (dumb USB ones in particular)
do little to no scan offload - it's all done in software.

Some NICs may do single channel at a time scanning; I haven't really
checked them out in detail.

iwn(4), the upcoming 7260 driver stuff, the new Qualcomm Atheros
11ac chipsets and the Atheros mobile/USB full-offload chips all
have complete scan engines in firmware.  We don't have to drive
any of it at all - the firmware just needs to be told what to scan,
when to scan, how long to scan.  It'll take care of going off
channel, pausing TX/RX appropriately, sending sleep notification
to the AP, sending probe requests and handling probe responses.
It'll do passive/active scan itself.  It's almost completely
transparent to the network stack - all we see are scan notifications
when it finishes scanning each channel and beacons/probe responses
when it does its thing.  Once it's done we get a final notification
that the scan is complete, with some scan results in the message.
The iwn(4) NICs handle doing active scanning too as an option
and will handle waiting appropriately on 5GHz passive channels
before active scanning.

There's some more refactoring, tidying up and lock assertions to
sprinkle around to tidy this whole thing up before I turn swscan.c
into another set of ic methods to override by the driver or
alternate scan module.  So in theory this is all one big no-op
commit.  In theory.

Tested:

* iwn(4) 5200, STA mode
* ath(4) 6205, STA mode
* ath(4) - various NICs, AP mode
2015-01-06 02:08:45 +00:00
Adrian Chadd
2c6179401b Add more debugging to try and track down this scan hang nonsense. 2014-12-21 01:15:55 +00:00
Adrian Chadd
f13a4d33ef Add some more debugging to the scan cancel methods - I'd like to see
what situations would cause the scan cancel's to not complete.
2014-12-20 23:41:37 +00:00
Adrian Chadd
92c59ab94f Document where in scan_task the scan state can change, and potentially
deal/log a warning if the scan flags change during one of those race
windows.

It's highly likely that I need to actually sit down and replace this
scan infrastructure at some point.  It has some other side effects too -
the scan task is a blocking task scheduled in the net80211 taskqueue;
so drivers that use this taskqueue have other things not run.  Eek.

If you see this printf happen then please let me know!
2014-12-20 19:41:31 +00:00
Adrian Chadd
1db2772f43 Make sure any waiters on the scan results get notified if the scan task
decides to do nothing.

If this isn't done, then a scan request whilst a scan occurs in an active
channel set or a completed channel set will hang.

Tested:

* Intel 5100, STA mode
2013-11-29 22:24:57 +00:00
Gleb Smirnoff
76039bc84f The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2013-10-26 17:58:36 +00:00
Adrian Chadd
e7f0d7cf47 Migrate the power-save functions to be overridable VAP methods.
This turns ieee80211_node_pwrsave(), ieee80211_sta_pwrsave() and
ieee80211_recv_pspoll() into methods.

The intent is to let drivers override these and tie into the power save
management pathway.

For ath(4), this is the beginning of forcing a node software queue to
stop and start as needed, as well as supporting "leaking" single frames
from the software queue to the hardware.

Right now, ieee80211_recv_pspoll() will attempt to transmit a single frame
to the hardware (whether it be a data frame on the power-save queue or
a NULL data frame) but the driver may have hardware/software queued frames
queued up.  This initial work is an attempt at providing the hooks required
to implement correct behaviour.

Allowing ieee80211_node_pwrsave() to be overridden allows the ath(4)
driver to pause and unpause the entire software queue for a given node.
It doesn't make sense to transmit anything whilst the node is asleep.

Please note that there are other corner cases to correctly handle -
specifically, setting the MORE data bit correctly on frames to a station,
as well as keeping the TIM updated.  Those particular issues can be
addressed later.
2012-10-02 17:45:19 +00:00
Adrian Chadd
66b74386c7 Attempt to catch scan cancellations at exactly the wrong time from occuring.
The scan code unlocks the comlock and calls into the driver.  It then
assumes the state hasn't changed from underneath it.

Although I haven't seen this particular condition trigger, I'd like to
be informed if I or anyone else sees it.

What I'm thinking may occur:

* A cancellation comes in during the scan_end call;
* the cancel flag is set;
* but it's never checked, so scandone isn't updated;
* .. and the interface stays in the STA power save mode.

It's a subtle race, if it even exists.

PR:		kern/163318
2012-03-02 02:53:43 +00:00
Bernhard Schmidt
27612ff8c9 Change return code semantics of start_scan_locked(). Instead of reporting
if a scan is running, report if a scan has been started. The return value
itself is not (yet) used anywhere in the tree and it is also not exported
to userspace.

MFC after:	1 month
2011-01-30 14:00:50 +00:00
Bernhard Schmidt
abf0f91e13 Honor the IEEE80211_SCAN_BGSCAN flag, which makes it possible to actually
request a background scan using IEEE80211_IOC_SCAN_BGSCAN.

MFC after:	1 month
2011-01-30 11:23:59 +00:00
Rui Paulo
59aa14a91d Implementation of the upcoming Wireless Mesh standard, 802.11s, on the
net80211 wireless stack. This work is based on the March 2009 D3.0 draft
standard. This standard is expected to become final next year.
This includes two main net80211 modules, ieee80211_mesh.c
which deals with peer link management, link metric calculation,
routing table control and mesh configuration and ieee80211_hwmp.c
which deals with the actually routing process on the mesh network.
HWMP is the mandatory routing protocol on by the mesh standard, but
others, such as RA-OLSR, can be implemented.

Authentication and encryption are not implemented.

There are several scripts under tools/tools/net80211/scripts that can be
used to test different mesh network topologies and they also teach you
how to setup a mesh vap (for the impatient: ifconfig wlan0 create
wlandev ... wlanmode mesh).

A new build option is available: IEEE80211_SUPPORT_MESH and it's enabled
by default on GENERIC kernels for i386, amd64, sparc64 and pc98.

Drivers that support mesh networks right now are: ath, ral and mwl.

More information at: http://wiki.freebsd.org/WifiMesh

Please note that this work is experimental. Also, please note that
bridging a mesh vap with another network interface is not yet supported.

Many thanks to the FreeBSD Foundation for sponsoring this project and to
Sam Leffler for his support.
Also, I would like to thank Gateworks Corporation for sending me a
Cambria board which was used during the development of this project.

Reviewed by:	sam
Approved by:	re (kensmith)
Obtained from:	projects/mesh11s
2009-07-11 15:02:45 +00:00
Weongyo Jeong
38812f8ee6 calls callout_drain(9) to un-schedule a scan timer to prevent a page
fault in softclock.

Submitted by:	sam
Reviewed by:	jhb, sam (original version), thompsa
2009-06-03 04:10:22 +00:00
Sam Leffler
5463c4a485 Overhaul monitor mode handling:
o replace DLT_IEEE802_11 support in net80211 with DLT_IEEE802_11_RADIO
  and remove explicit bpf support from wireless drivers; drivers now
  use ieee80211_radiotap_attach to setup shared data structures that
  hold the radiotap header for each packet tx/rx
o remove rx timestamp from the rx path; it was used only by the tdma support
  for debugging and was mostly useless due to it being 32-bits and mostly
  unavailable
o track DLT_IEEE80211_RADIO bpf attachments and maintain per-vap and
  per-com state when there are active taps
o track the number of monitor mode vaps
o use bpf tap and monitor mode vap state to decide when to collect radiotap
  state and dispatch frames; drivers no longer explicitly directly check
  bpf state or use bpf calls to tap frames
o handle radiotap state updates on channel change in net80211; drivers
  should not do this (unless they bypass net80211 which is almost always
  a mistake)
o update various drivers to be more consistent/correct in handling radiotap
o update ral to include TSF in radiotap'd frames
o add promisc mode callback to wi

Reviewed by:	cbzimmer, rpaulo, thompsa
2009-05-20 20:00:40 +00:00
Andrew Thompson
5efea30f03 Create a taskqueue for each wireless interface which provides a serialised
sleepable context for net80211 driver callbacks. This removes the need for USB
and firmware based drivers to roll their own code to defer the chip programming
for state changes, scan requests, channel changes and mcast/promisc updates.
When a driver callback completes the hardware state is now guaranteed to have
been updated and is in sync with net80211 layer.

This nukes around 1300 lines of code from the wireless device drivers making
them more readable and less race prone.

The net80211 layer has been updated as follows
 - all state/channel changes are serialised on the taskqueue.
 - ieee80211_new_state() always queues and can now be called from any context
 - scanning runs from a single taskq function and executes to completion. driver
   callbacks are synchronous so the channel, phy mode and rx filters are
   guaranteed to be set in hardware before probe request frames are
   transmitted.

Help and contributions from Sam Leffler.

Reviewed by:	sam
2009-05-02 15:14:18 +00:00
Sam Leffler
26d39e2c68 o add ic_rt to track the rate table for the current channel; this enables
calculation of packet transmit times to do things like check txop limits
o remove equivalent driver code and convert to use net80211 state
2009-03-29 21:17:08 +00:00
Sam Leffler
110a70e3b2 display min/max dwell times in msecs in debug msgs 2009-02-22 18:46:36 +00:00
Sam Leffler
6a76ae216e Add modes for 1/2 and 1/4-width channels so we have separate roaming
and xmit parameters.  This makes it possible to use tdma on fractional
channels.
o add IEEE80211_MODE_HALF and IEEE80211_MODE_QUARTER; note these are
  band-agnostic (may need revisiting)
o setup all default rates in ic_sup_rates instead of doing it only
  for active modes; we need these to calculate the default tx parameters
  which are not recalculated after a regulatory update (can't just
  recalculate after installing a new channel list because we might
  clobber user settings)
o remove special case code in ieee80211_get_suprates; this is now
  a candidate for an inline or removal
o add various entries for new modes (roaming+tx params, wme, rate
  mapping, scan set setup, country ie construction, tdma, basic rates)

Note these modes are intentionally not visible through if_media.
2009-02-19 05:21:54 +00:00
Sam Leffler
82c990a4ef simplify setting up the roaming parameters; writing default parameters only
for active modes hasn't turned out to be useful so just define a const table
and copy it in place
2009-02-19 04:37:44 +00:00
Sam Leffler
e2126dec84 convert MALLOC/FREE to malloc/free 2008-12-18 23:00:09 +00:00
Dag-Erling Smørgrav
c5abbba314 Revert the removal of the MALLOC and FREE macros from the net80211 code.
Requested by:	sam
2008-10-23 19:57:13 +00:00
Dag-Erling Smørgrav
1ede983cc9 Retire the MALLOC and FREE macros. They are an abomination unto style(9).
MFC after:	3 months
2008-10-23 15:53:51 +00:00
Sam Leffler
aa0fbc732a Simplify some contorted logic that wrongly left ISCAN_DISCARD set
in certain cases causing the current ap to be lost from the scan cache.

Obtained from:	Atheros (original bug)
2008-05-28 23:15:24 +00:00
Sam Leffler
978359b3f6 Revise lock name handling:
o construct a name for the com lock as done for other locks
o pass the device name to IEEE80211_LOCK_INIT so the mtx name
  is constructed as foo_com_lock
o introduce *_LOCK_OBJ macro's to hide the lock contents and
  minimize redundant code
2008-05-28 23:10:53 +00:00
Sam Leffler
b032f27c36 Multi-bss (aka vap) support for 802.11 devices.
Note this includes changes to all drivers and moves some device firmware
loading to use firmware(9) and a separate module (e.g. ral).  Also there
no longer are separate wlan_scan* modules; this functionality is now
bundled into the wlan module.

Supported by:	Hobnob and Marvell
Reviewed by:	many
Obtained from:	Atheros (some bits)
2008-04-20 20:35:46 +00:00
Sam Leffler
b161c30793 silence complaint about not loading the wlan_scan_monitor module;
it does not exist and is not needed as monitor mode operation has
always required setting the current channel

Reviewed by:	thompsa
MFC after:	1 week
2007-10-24 20:20:41 +00:00
Andrew Thompson
d81b3a5588 Fix scanning issues since the new net80211 code went in
- provide dummy routines for ic_scan_curchan and ic_scan_mindwell, we do not support those operations.
- add ieee80211_scan_done() to tell the scanning module that all channels have been scanned.
- pass IEEE80211_S_SCAN state off to net80211 so it can initiate scanning
- fix overflow in the rates array
- scale the rate value passed back from the firmware scan to the units that net80211 uses.

Submitted by:	Token
Reviewed by:	sam, avatar
Approved by:	re (kensmith)
2007-06-30 21:39:21 +00:00
Andrew Thompson
b54b1bab4b Change the channel number in the scan results struct to be a pointer to the
operating channel and use this in the scan cache rather than directly using
ic_curchan. Some firmware cards can only do a full scan and so ic_curchan does
not have the correct value.

Also add IEEE80211_CHAN2IEEE to directly dereference ic_ieee from the channel
to be used in the fast path.

Reviewed by:	sam, sephe
Approved by:	re (kensmith)
2007-06-30 21:23:23 +00:00
Sam Leffler
68e8e04e93 Update 802.11 wireless support:
o major overhaul of the way channels are handled: channels are now
  fully enumerated and uniquely identify the operating characteristics;
  these changes are visible to user applications which require changes
o make scanning support independent of the state machine to enable
  background scanning and roaming
o move scanning support into loadable modules based on the operating
  mode to enable different policies and reduce the memory footprint
  on systems w/ constrained resources
o add background scanning in station mode (no support for adhoc/ibss
  mode yet)
o significantly speedup sta mode scanning with a variety of techniques
o add roaming support when background scanning is supported; for now
  we use a simple algorithm to trigger a roam: we threshold the rssi
  and tx rate, if either drops too low we try to roam to a new ap
o add tx fragmentation support
o add first cut at 802.11n support: this code works with forthcoming
  drivers but is incomplete; it's included now to establish a baseline
  for other drivers to be developed and for user applications
o adjust max_linkhdr et. al. to reflect 802.11 requirements; this eliminates
  prepending mbufs for traffic generated locally
o add support for Atheros protocol extensions; mainly the fast frames
  encapsulation (note this can be used with any card that can tx+rx
  large frames correctly)
o add sta support for ap's that beacon both WPA1+2 support
o change all data types from bsd-style to posix-style
o propagate noise floor data from drivers to net80211 and on to user apps
o correct various issues in the sta mode state machine related to handling
  authentication and association failures
o enable the addition of sta mode power save support for drivers that need
  net80211 support (not in this commit)
o remove old WI compatibility ioctls (wicontrol is officially dead)
o change the data structures returned for get sta info and get scan
  results so future additions will not break user apps
o fixed tx rate is now maintained internally as an ieee rate and not an
  index into the rate set; this needs to be extended to deal with
  multi-mode operation
o add extended channel specifications to radiotap to enable 11n sniffing

Drivers:
o ath: add support for bg scanning, tx fragmentation, fast frames,
       dynamic turbo (lightly tested), 11n (sniffing only and needs
       new hal)
o awi: compile tested only
o ndis: lightly tested
o ipw: lightly tested
o iwi: add support for bg scanning (well tested but may have some
       rough edges)
o ral, ural, rum: add suppoort for bg scanning, calibrate rssi data
o wi: lightly tested

This work is based on contributions by Atheros, kmacy, sephe, thompsa,
mlaier, kevlo, and others.  Much of the scanning work was supported by
Atheros.  The 11n work was supported by Marvell.
2007-06-11 03:36:55 +00:00