Commit Graph

25 Commits

Author SHA1 Message Date
Stephen Hemminger 68aae11674 [MAC80211]: use internal network device stats
Stats are now available for device usage inside network_device

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:31 -07:00
Johannes Berg 7848ba7d7a [MAC80211]: rework hardware crypto flags
This patch reworks the various hardware crypto related
flags to make them more local, i.e. put them with each
key or each packet instead of into the hw struct.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:27 -07:00
Johannes Berg b708e61062 [MAC80211]: remove turbo modes
This patch removes all mention of the atheros turbo modes that
can't possibly work properly anyway since in some places we don't
check for them when we should.

I have no idea what the iwlwifi drivers were doing with these but
it can't possibly have been correct.

Cc: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:27 -07:00
Johannes Berg d4e46a3d98 [MAC80211]: fix race conditions with keys
During receive processing, we select the key long before using it and
because there's no locking it is possible that we kfree() the key
after having selected it but before using it for crypto operations.
Obviously, this is bad.

Secondly, during transmit processing, there are two possible races: We
have a similar race between select_key() and using it for encryption,
but we also have a race here between select_key() and hardware
encryption (both when a key is removed.)

This patch solves these issues by using RCU: when a key is to be freed,
we first remove the pointer from the appropriate places (sdata->keys,
sdata->default_key, sta->key) using rcu_assign_pointer() and then
synchronize_rcu(). Then, we can safely kfree() the key and remove it
from the hardware. There's a window here where the hardware may still
be using it for decryption, but we can't work around that without having
two hardware callbacks, one to disable the key for RX and one to disable
it for TX; but the worst thing that will happen is that we receive a
packet decrypted that we don't find a key for any more and then drop it.

When we add a key, we first need to upload it to the hardware and then,
using rcu_assign_pointer() again, link it into our structures.

In the code using keys (TX/RX paths) we use rcu_dereference() to get the
key and enclose the whole tx/rx section in a rcu_read_lock() ...
rcu_read_unlock() block. Because we've uploaded the key to hardware
before linking it into internal structures, we can guarantee that it is
valid once get to into tx().

One possible race condition remains, however: when we have hardware
acceleration enabled and the driver shuts down the queues, we end up
queueing the frame. If now somebody removes the key, the key will be
removed from hwaccel and then then driver will be asked to encrypt the
frame with a key index that has been removed. Hence, drivers will need
to be aware that the hw_key_index they are passed might not be under
all circumstances. Most drivers will, however, simply ignore that
condition and encrypt the frame with the selected key anyway, this
only results in a frame being encrypted with a wrong key or dropped
(rightfully) because the key was not valid. There isn't much we can
do about it unless we want to walk the pending frame queue every time
a key is removed and remove all frames that used it.

This race condition, however, will most likely be solved once we add
multiqueue support to mac80211 because then frames will be queued
further up the stack instead of after being processed.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:26 -07:00
Johannes Berg c9ee23dfac [MAC80211]: make assoc_ap a flag
The sta_info.assoc_ap value is used as a flag, move it
into flags.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:58 -07:00
Johannes Berg 8dc06a1c61 [MAC80211]: improve key selection comment
When I changed the code there I forgot to mention what happens
with multicast frames in a regular BSS and keep wondering myself
if the code is correct. Add appropriate comments.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:56 -07:00
John W. Linville b331615722 [MAC80211]: filter locally-originated multicast frames
In STA mode, the AP will echo our traffic.  This includes multicast
traffic.

Receiving these frames confuses some protocols and applications,
notably IPv6 Duplicate Address Detection.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:56 -07:00
Larry Finger 6c55aa9735 [MAC80211]: Remove overly sticky averaging filters for rssi, signal, noise
The current version of wireless statistics contains a bug in the averaging
that makes the numbers be too sticky and not react to small changes. This
patch removes all averaging.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:54 -07:00
Johannes Berg 11a843b7e1 [MAC80211]: rework key handling
This moves all the key handling code out from ieee80211_ioctl.c
into key.c and also does the following changes including documentation
updates in mac80211.h:

 1) Turn off hardware acceleration for keys when the interface
    is down. This is necessary because otherwise monitor
    interfaces could be decrypting frames for other interfaces
    that are down at the moment. Also, it should go some way
    towards better suspend/resume support, in any case the
    routines used here could be used for that as well.
    Additionally, this makes the driver interface nicer, keys
    for a specific local MAC address are only ever present
    while an interface with that MAC address is enabled.

 2) Change driver set_key() callback interface to allow only
    return values of -ENOSPC, -EOPNOTSUPP and 0, warn on all
    other return values. This allows debugging the stack when
    a driver notices it's handed a key while it is down.

 3) Invert the flag meaning to KEY_FLAG_UPLOADED_TO_HARDWARE.

 4) Remove REMOVE_ALL_KEYS command as it isn't used nor do we
    want to use it, we'll use DISABLE_KEY for each key. It is
    hard to use REMOVE_ALL_KEYS because we can handle multiple
    virtual interfaces with different key configuration, so we'd
    have to keep track of a lot of state for this and that isn't
    worth it.

 5) Warn when disabling a key fails, it musn't.

 6) Remove IEEE80211_HW_NO_TKIP_WMM_HWACCEL in favour of per-key
    IEEE80211_KEY_FLAG_WMM_STA to let driver sort it out itself.

 7) Tell driver that a (non-WEP) key is used only for transmission
    by using an all-zeroes station MAC address when configuring.

 8) Change the set_key() callback to have access to the local MAC
    address the key is being added for.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:53 -07:00
Johannes Berg 8f20fc2498 [MAC80211]: embed key conf in key, fix driver interface
This patch embeds the struct ieee80211_key_conf into struct ieee80211_key
and thus avoids allocations and having data present twice.

This required some more changes:
 1) The removal of the IEEE80211_KEY_DEFAULT_TX_KEY key flag.
    This flag isn't used by drivers nor should it be since
    we have a set_key_idx() callback. Maybe that callback needs
    to be extended to include the key conf, but only a driver that
    requires it will tell.
 2) The removal of the IEEE80211_KEY_DEFAULT_WEP_ONLY key flag.
    This flag is global, so it shouldn't be passed in the key
    conf structure. Pass it to the function instead.

Also, this patch removes the AID parameter to the set_key() callback
because it is currently unused and the hardware currently cannot know
about the AID anyway. I suspect this was used with some hardware that
actually selected the AID itself, but that functionality was removed.

Additionally, I've removed the ALG_NULL key algorithm since we have
ALG_NONE.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:51 -07:00
Jiri Slaby 13262ffd49 [MAC80211]: Remove bitfields from struct ieee80211_sub_if_data
mac80211, remove bitfields from struct ieee80211_sub_if_data

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:50 -07:00
Jiri Slaby badffb725c [MAC80211]: Remove bitfields from struct ieee80211_txrx_data
mac80211, remove bitfields from struct ieee80211_txrx_data

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:49 -07:00
Jiri Slaby e8bf96495c [MAC80211]: Remove bitfields from struct ieee80211_tx_packet_data
remove bitfields from struct ieee80211_tx_packet_data

[Johannes: completely clear flags in ieee80211_remove_tx_extra]

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:48 -07:00
Johannes Berg eb063c1702 [MAC80211]: refactor event sending
Create a new file event.c that will contain code to send mac/mlme
events to userspace. For now put the Michael MIC failure condition
into it and remove sending of that condition via the management
interface, hostapd interestingly doesn't do anything when it gets
such a packet besides printing a message, it reacts only on the
private iwevent.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:47 -07:00
Johannes Berg 3017b80bf0 [MAC80211]: fix software decryption
When doing key selection for software decryption, mac80211 gets
a few things wrong: it always uses pairwise keys if configured,
even if the frame is addressed to a multicast address. Also, it
doesn't allow using a key index of zero if a pairwise key has
also been found.

This patch changes the key selection code to be (more) in line
with the 802.11 specification. I have confirmed that with this,
multicast frames are correctly decrypted and I've tested with
WEP as well.

While at it, I've cleaned up the semantics of the hardware flags
IEEE80211_HW_WEP_INCLUDE_IV and IEEE80211_HW_DEVICE_HIDES_WEP
and clarified them in the mac80211.h header; it is also now
allowed to set the IEEE80211_HW_DEVICE_HIDES_WEP option even if
it only applies to frames that have been decrypted by the hw,
unencrypted frames must be dropped but encrypted frames that
the hardware couldn't handle can be passed up unmodified.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:48:44 -07:00
Johannes Berg 643856729e [MAC80211]: remove ieee80211_msg_wep_frame_unknown_key
Neither hostapd nor wpa_supplicant really use it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:48:43 -07:00
Johannes Berg 1a84f3fd14 [MAC80211]: ratelimit some RX messages
Many if not all of these messages can be triggered by sending
a few rogue frames which is trivially done and then we overflow
our logs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:42 -07:00
Johannes Berg 2a8a9a88fc [MAC80211]: avoid copying packets to interfaces that are down
David Woodhouse noticed that under some circumstances the number of slab
allocations kept growing. After looking a bit, this seemed to happen
when you had a management mode interface that was *down*.

The reason for this is that when the device is down, all management
frames get queued to the in-kernel MLME (via ieee80211_sta_rx_mgmt) but
then the sta work is invoked but doesn't run when the netif is down.
When you then bring the interface up, all such frames are freed, but if
you change the mode all of them are lost because the skb queue is
reinitialised as soon as you go back to managed mode. The skb queue is
correctly cleared when the interface is brought down, but the code
doesn't account for the fact that it may be filled while it is not up.

This patch should fix the issue by simply ignoring all interfaces that
are down when going through the RX handlers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:39 -07:00
Johannes Berg 340e11f332 [MAC80211]: rx cleanups (2)
Some more outdenting to make the code more readable.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:32 -07:00
Johannes Berg 52865dfd52 [MAC80211]: fix bug for per-sta stats
pre_rx handlers can't really touch sta since for IBSS it might not be
assigned yet, it can create sta info structs on-the-fly.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:32 -07:00
Johannes Berg 23a24defa0 [MAC80211]: split up __ieee80211_rx
The really indented part that does the huge switch on the interface
type is a nuisance. Put it into an own function 'prepare_for_handlers'.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:31 -07:00
Johannes Berg 570bd537a9 [MAC80211]: split ieee80211_rx_h_check handler
The ieee80211_rx_h_check handler really does two things, it's
a lot easier to understand if it's split into ieee80211_rx_h_check
and ieee80211_rx_h_load_key, and it may be possible in the future
to optimise the key loading to not do it for each interface.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:31 -07:00
Johannes Berg 8e6f003274 [MAC80211]: rx cleanups (1)
Make some really indented code more readable by outdenting.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:30 -07:00
Johannes Berg 6e0d114d52 [MAC80211]: move QoS rx handlers into rx.c
This patch moves the QoS handlers into rx.c making it possible
to compile wme.c only when NET_SCHED is defined.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:30 -07:00
Johannes Berg 571ecf676d [MAC80211]: split RX handlers into own file
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:29 -07:00