Otherwise we risk leaking information via timing side channel.
Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a key is reinstalled we can reset the replay counters
etc. which can lead to nonce reuse and/or replay detection
being impossible, breaking security properties, as described
in the "KRACK attacks".
In particular, CVE-2017-13080 applies to GTK rekeying that
happened in firmware while the host is in D3, with the second
part of the attack being done after the host wakes up. In
this case, the wpa_supplicant mitigation isn't sufficient
since wpa_supplicant doesn't know the GTK material.
In case this happens, simply silently accept the new key
coming from userspace but don't take any action on it since
it's the same key; this keeps the PN replay counters intact.
Change-Id: Ie3402dce344b6471a2a213722eef66da8f14f4f9
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
commit 28a9bc68124c319b2b3dc861e80828a8865fd1ba upstream.
When writing the code to allow per-station GTKs, I neglected to
take into account the management frame keys (index 4 and 5) when
freeing the station and only added code to free the first four
data frame keys.
Fix this by iterating the array of keys over the right length.
Fixes: e31b82136d ("cfg80211/mac80211: allow per-station GTKs")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of calling synchronize_net() for every key
on an interface or when a station is removed, do it
only once for all keys in both of these cases.
As a side-effect, removing station keys now always
calls synchronize_net() even if there are no keys,
which fixes an issue with station removal happening
in the driver while the station could still be used
for TX.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a key is allocated but not really added, there's no
need to go through the entire teardown process. Also, if
adding a key fails, ieee80211_key_link() can take care of
freeing it instead of the (only) caller.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
During roaming, the crypto_tx_tailroom_needed_cnt counter
will often take values 2,1,0,1,2 because first keys are
removed and then new keys are added. This is inefficient
because during the 0->1 transition, synchronize_net must
be called to avoid packet races, although typically no
packets would be flowing during that time.
To avoid that, defer the decrement (2->1, 1->0) when keys
are removed (by half a second). This means the counter
will really have the values 2,2,2,3,4 ... 2, thus never
reaching 0 and having to do the 0->1 transition.
Note that this patch entirely disregards the drivers for
which this optimisation was done to start with, for them
the key removal itself will be expensive because it has
to synchronize_net() after the counter is incremented to
remove the key from HW crypto. For them the sequence will
look like this: 0,1,0,1,0,1,0,1,0 (*) which is clearly a
lot more inefficient. This could be addressed separately,
during key removal the 0->1->0 sequence isn't necessary.
(*) it starts at 0 because HW crypto is on, then goes to
1 when HW crypto is disabled for a key, then back to
0 because the key is deleted; this happens for both
keys in the example. When new keys are added, it goes
to 1 first because they're added in software; when a
key is moved to hardware it goes back to 0
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no driver using this flag, so it seems
that all drivers support HW crypto with WMM or
don't support it at all. Remove the flag and
code setting it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since now we disconnect before suspend, various code which save
connection state can now be removed from suspend and resume
procedure. Cleanup on resume side is smaller as ieee80211_reconfig()
is also used for H/W restart.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are hardwares which support offload of data packets
for example when auto ARP is enabled the hw will send
the ARP response. In such cases if WEP encryption is
configured the hw must know the default WEP key in order
to encrypt the packets correctly.
When hw_accel is enabled and encryption type is set to WEP,
the driver should get the default key index from mac80211.
Signed-off-by: Yoni Divinsky <yoni.divinsky@ti.com>
[cleanups, fixes, documentation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Introduce IEEE80211_NUM_TIDS in the generic 802.11
header file and use it in place of STA_TID_NUM and
NUM_RX_DATA_QUEUES which are both really the number
of TIDs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
__ieee80211_key_destroy() calls synchronize_rcu() in
order to sync the tx path before destroying the key.
However, synching the tx path can be done with
synchronize_net() as well, which is usually faster
(the timing might be important for roaming scenarios).
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This API call was intended to be used by drivers
if they want to optimize key handling by removing
one key when another is added. Remove it since no
driver is using it. If needed, it can always be
added back.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are a few things that make the logging and
debugging in mac80211 less useful than it should
be right now:
* a lot of messages should be pr_info, not pr_debug
* wholesale use of pr_debug makes it require *both*
Kconfig and dynamic configuration
* there are still a lot of ifdefs
* the style is very inconsistent, sometimes the
sdata->name is printed in front
Clean up everything, introducing new macros and
separating out the station MLME debugging into
a new Kconfig symbol.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some files implicitly get this via mesh.h
which itself doesn't need it, so move the
inclusion into the right files. Some other
files don't need it at all but include it,
so remove it from there.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If a station couldn't be uploaded to the driver but
is still kept (only in IBSS mode) we still shouldn't
try to program the keys for it into hardware; fix
this bug by skipping the key upload in this case.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Setting keys and updating TKIP keys must use the
BSS sdata (not AP_VLAN), so we translate. Move
the translation into driver-ops wrappers instead
of having it inline in the code to simplify the
normal code flow.
The same can be done for sta_add/remove which
already does the translation in the wrapper.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some cards can generate CCMP IVs in HW, but require the space for the IV
to be pre-allocated in the frame at the correct offset. Add a key flag
that allows us to achieve this.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The flaglock in struct sta_info has long been
something that I wanted to get rid of, this
finally does the conversion to atomic bitops.
The conversion itself is straight-forward in
most places, a few things needed to change a
bit since we can no longer use multiple bits
at the same time.
On x86-64, this is a fairly significant code
size reduction:
text data bss dec hex
427861 23648 1008 452517 6e7a5 before
425383 23648 976 450007 6ddd7 after
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ieee80211_iter_keys() currently returns keys in
the backward order they were installed in, which
is a bit confusing. Add them to the tail of the
key list to make sure iterations go in the same
order that keys were originally installed in.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In order to implement GTK rekeying, the device needs
to be able to encrypt frames with the right PN/IV and
check the PN/IV in RX frames. To be able to tell it
about all those counters, we need to be able to get
them from mac80211, this adds the required API.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Our current TKIP code races against itself on TX
since we can process multiple packets at the same
time on different ACs, but they all share the TX
context for TKIP. This can lead to bad IVs etc.
Also, the crypto offload helper code just obtains
the P1K/P2K from the cache, and can update it as
well, but there's no guarantee that packets are
really processed in order.
To fix these issues, first introduce a spinlock
that will protect the IV16/IV32 values in the TX
context. This first step makes sure that we don't
assign the same IV multiple times or get confused
in other ways.
Secondly, change the way the P1K cache works. I
add a field "p1k_iv32" that stores the value of
the IV32 when the P1K was last recomputed, and
if different from the last time, then a new P1K
is recomputed. This can cause the P1K computation
to flip back and forth if packets are processed
out of order. All this also happens under the new
spinlock.
Finally, because there are argument differences,
split up the ieee80211_get_tkip_key() API into
ieee80211_get_tkip_p1k() and ieee80211_get_tkip_p2k()
and give them the correct arguments.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This adds the necessary mac80211 APIs to support
GTK rekey offload, mirroring the functionality
from cfg80211.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When in suspend/wowlan, devices might implement crypto
offload differently (more features), and might require
reprogramming keys for the WoWLAN (as it is the case
for Intel devices that use another uCode image). Thus
allow the driver to iterate all keys in this context.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Based on inputs from Johannes Berg <johannes@sipsolutions.net>
from http://article.gmane.org/gmane.linux.kernel.wireless.general/68193
and http://article.gmane.org/gmane.linux.kernel.wireless.general/71702
In xmit path, devices that do full hardware crypto (including
MMIC and ICV) need no tailroom. For such devices, tailroom
reservation can be skipped if all the keys are programmed into
the hardware (i.e software crypto is not used for any of the
keys) and none of the keys wants software to generate Michael
MIC and IV.
v2: Added check for IV along with MMIC.
Reported-by: Fabio Rossi <rossi.f@inwind.it>
Tested-by: Fabio Rossi <rossi.f@inwind.it>
Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Cc: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
v3: Fixing races to avoid WARNING: at net/mac80211/wpa.c:397
ccmp_encrypt_skb+0xc4/0x1f0
Reported-by: Andreas Hartmann <andihartmann@01019freenet.de>
Tested-by: Andreas Hartmann <andihartmann@01019freenet.de>
v4: Added links with message ID
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This adds sparse RCU annotations to most of
mac80211, only the mesh code remains to be
done.
Due the the previous patches, the annotations
are pretty simple. The only thing that this
actually changes is removing the RCU usage of
key->sta in debugfs since this pointer isn't
actually an RCU-managed pointer (it only has
a single assignment done before the key even
goes live). As that is otherwise harmless, I
decided to make it part of this patch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The code in ieee80211_del_key() doesn't acquire the
key_mtx properly when it dereferences the keys. It
turns out that isn't actually necessary since the
key_mtx itself seems to be redundant since all key
manipulations are done under the RTNL, but as long
as we have the key_mtx we should use it the right
way too.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In xmit path, devices that do full hardware crypto (including
TKIP MMIC) need no tailroom. For such devices, tailroom
reservation can be skipped if all the keys are programmed into
the hardware (i.e software crypto is not used for any of the
keys) and none of the keys wants software to generate Michael
MIC.
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch moves 'key' dereference after BUG_ON(!key) so that when key is NULL
we will see proper trace instead of oops.
Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The ieee80211_key struct can be kfree()d several times in the function, for
example if some of the key setup functions fails beforehand, but there's no
check if the struct is still valid before we call memcpy() and INIT_LIST_HEAD()
on it. In some cases (like it was in my case), if there's missing aes-generic
module it could lead to the following kernel OOPS:
Unable to handle kernel NULL pointer dereference at virtual address 0000018c
....
PC is at memcpy+0x80/0x29c
...
Backtrace:
[<bf11c5e4>] (ieee80211_key_alloc+0x0/0x234 [mac80211]) from [<bf1148b4>] (ieee80211_add_key+0x70/0x12c [mac80211])
[<bf114844>] (ieee80211_add_key+0x0/0x12c [mac80211]) from [<bf070cc0>] (__cfg80211_set_encryption+0x2a8/0x464 [cfg80211])
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The key documentation is slightly out of date, fix
that. Also, the list entry in the key struct is no
longer used that way, so list_del_init() isn't
necessary any more there.
Finally, ieee80211_key_link() is no longer invoked
under RCU read lock, but rather with an appropriate
station lock held.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
commit ad0e2b5a00
Author: Johannes Berg <johannes.berg@intel.com>
Date: Tue Jun 1 10:19:19 2010 +0200
mac80211: simplify key locking
removed the synchronization against RCU and thus
opened a race window where we can use a key for
TX while it is already freed. Put a synchronisation
into the right place to close that window.
Reported-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Cc: stable@kernel.org [2.6.36+]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add support for split default keys (unicast
and multicast) in mac80211.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When using AP VLAN interfaces, each VLAN interface should be in its own
broadcast domain. Hostapd achieves this by assigning different GTKs to
different AP VLAN interfaces.
However, mac80211 drivers are not aware of AP VLAN interfaces and as
such mac80211 sends the GTK to the driver in the context of the base AP
mode interface. This causes problems when multiple AP VLAN interfaces
are used since the driver will use the same key slot for the different
GTKs (there's no way for the driver to distinguish the different GTKs
from different AP VLAN interfaces). Thus, only the clients associated
to one AP VLAN interface (the one that was created last) can actually
use broadcast traffic.
Fix this by not programming any GTKs for AP VLAN interfaces into the hw
but fall back to using software crypto. The GTK for the underlying AP
interface is still sent to the driver.
That means, broadcast traffic to stations associated to an AP VLAN
interface is encrypted in software whereas broadcast traffic to
stations associated to the non-VLAN AP interface is encrypted in
hardware.
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This adds API to allow adding per-station GTKs,
updates mac80211 to support it, and also allows
drivers to remove a key from hwaccel again when
this may be necessary due to multiple GTKs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Instead of using a WARN_ON(!mutex_is_locked())
use lockdep_assert_held() which compiles away
completely when lockdep isn't enabled, and
also is a more accurate assertion since it
checks that the current thread is holding the
mutex.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Allow drivers to specify their own set of cipher
suites to advertise vendor-specific ciphers. The
driver is then required to implement hardware
crypto offload for it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Standardize logging messages from
printk(KERN_<level> "%s: " fmt , wiphy_name(foo), args);
to
wiphy_<level>(foo, fmt, args);
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
There's no need to keep separate if statements
for setting up the CCMP/AES-CMAC tfm structs;
move that into the existing switch statement.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Currently, mac80211 translates the cfg80211
cipher suite selectors into ALG_* values.
That isn't all too useful, and some drivers
benefit from the distinction between WEP40
and WEP104 as well. Therefore, convert it
all to use the cipher suite selectors.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ieee80211_add_key() currently returns -ENOMEM in case of any error,
including a missing crypto algorithm. Change ieee80211_key_alloc()
and ieee80211_aes_{key_setup_encrypt,cmac_key_setup}() to encode
errors with ERR_PTR() rather than returning NULL, and change
ieee80211_add_key() accordingly.
Compile-tested only.
Reported-by: Marcin Owsiany <porridge@debian.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Key locking simplification removed key->sdata != NULL verification from
ieee80211_key_free(). While that is fine for most use cases, there is one
path where this function can be called with an unlinked key (i.e.,
key->sdata == NULL && key->local == NULL). This results in a NULL pointer
dereference with the current implementation. This is known to happen at
least with FT protocol when wpa_supplicant tries to configure the key
before association.
Avoid the issue by passing in the local pointer to
ieee80211_key_free(). In addition, do not clear the key from hw_accel
or debugfs if it has not yet been added. At least the hw_accel one could
trigger another NULL pointer dereference.
Signed-off-by: Jouni Malinen <j@w1.fi>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When management frame protection (IEEE 802.11w) is used, we must use a
separate counter for tracking received CCMP packet number for the
management frames. The previously used NUM_RX_DATA_QUEUESth queue was
shared with data frames when QoS was not used and that can cause
problems in detecting replays incorrectly for robust management frames.
Add a new counter just for robust management frames to avoid this issue.
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Since I recently made station management able
to sleep, I can now rework key management as
well; since it will no longer need a spinlock
and can also use a mutex instead, a bunch of
code to allow drivers' set_key to sleep while
key management is protected by a spinlock can
now be removed.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Jason A. Donenfeld
Johannes Berg
Stanislaw Gruszka
Yoni Divinsky
Eliad Peller
John W. Linville
Arik Nemtsov
Paul Gortmaker
Yogesh Ashok Powar
Mohammed Shafi Shajakhan
Mariusz Kozlowski
Petr Štetiar
Helmut Schaa
Joe Perches
Ben Hutchings
Jouni Malinen
Jouni Malinen