Both old and new cannot be NULL at the same time, hence checking
new when old is not NULL is unnecessary.
Also, notice that new is being dereferenced before it is checked:
idx = new->conf.keyidx;
The above triggers a static code analysis warning.
Address this by removing the NULL check on new and adding a code
comment based on the following piece of code:
387 /* caller must provide at least one old/new */
388 if (WARN_ON(!new && !old))
389 return 0;
Addresses-Coverity-ID: 1473176 ("Dereference before null check")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Rekeying PTK keys without "Extended Key ID for Individually Addressed
Frames" did use a procedure not suitable to replace in-use keys and
could caused the following issues:
1) Freeze caused by incoming frames:
If the local STA installed the key prior to the remote STA we still
had the old key active in the hardware when mac80211 switched over
to the new key.
Therefore there was a window where the card could hand over frames
decoded with the old key to mac80211 and bump the new PN (IV) value
to an incorrect high number. When it happened the local replay
detection silently started to drop all frames sent with the new key.
2) Freeze caused by outgoing frames:
If mac80211 was providing the PN (IV) and handed over a clear text
frame for encryption to the hardware prior to a key change the
driver/card could have processed the queued frame after switching
to the new key. This bumped the PN value on the remote STA to an
incorrect high number, tricking the remote STA to discard all frames
we sent later.
3) Freeze caused by RX aggregation reorder buffer:
An aggregation session started with the old key and ending after the
switch to the new key also bumped the PN to an incorrect high number,
freezing the connection quite similar to 1).
4) Freeze caused by repeating lost frames in an aggregation session:
A driver could repeat a lost frame and encrypt it with the new key
while in a TX aggregation session without updating the PN for the
new key. This also could freeze connections similar to 2).
5) Clear text leak:
Removing encryption offload from the card cleared the encryption
offload flag only after the card had deleted the key and we did not
stop TX during the rekey. The driver/card could therefore get
unencrypted frames from mac80211 while no longer be instructed to
encrypt them.
To prevent those issues the key install logic has been changed:
- Mac80211 divers known to be able to rekey PTK0 keys have to set
@NL80211_EXT_FEATURE_CAN_REPLACE_PTK0,
- mac80211 stops queuing frames depending on the key during the replace
- the key is first replaced in the hardware and after that in mac80211
- and mac80211 stops/blocks new aggregation sessions during the rekey.
For drivers not setting
@NL80211_EXT_FEATURE_CAN_REPLACE_PTK0 the user space must avoid PTK
rekeys if "Extended Key ID for Individually Addressed Frames" is not
being used. Rekeys for mac80211 drivers without this flag will generate a
warning and use an extra call to ieee80211_flush_queues() to both
highlight and try to prevent the issues with not updated drivers.
The core of the fix changes the key install procedure from:
- atomic switch over to the new key in mac80211
- remove the old key in the hardware (stops encryption offloading, fall
back to software encryption with a potential clear text packet leak
in between)
- delete the inactive old key in mac80211
- enable hardware encryption offloading for the new key
to:
- if it's a PTK mark the old key as tainted to drop TX frames with the
outgoing key
- replace the key in hardware with the new one
- atomic switch over to the new (not marked as tainted) key in
mac80211 (which also resumes TX)
- delete the inactive old key in mac80211
With the new sequence the hardware will be unable to decrypt frames
encrypted with the old key prior to switching to the new key in mac80211
and thus prevent PNs from packets decrypted with the old key to be
accounted against the new key.
For that to work the drivers have to provide a clear boundary.
Mac80211 drivers setting @NL80211_EXT_FEATURE_CAN_REPLACE_PTK0 confirm
to provide it and mac80211 will then be able to correctly rekey in-use
PTK keys with those drivers.
The mac80211 requirements for drivers to set the flag have been added to
the "Hardware crypto acceleration" documentation section. It drills down
to:
The drivers must not hand over frames decrypted with the old key to
mac80211 once the call to set_key() with %DISABLE_KEY has been
completed. It's allowed to either drop or continue to use the old key
for any outgoing frames which are already in the queues, but it must not
send out any of them unencrypted or encrypted with the new key.
Even with the new boundary in place aggregation sessions with the
reorder buffer are problematic:
RX aggregation session started prior and completed after the rekey could
still dump frames received with the old key at mac80211 after it
switched over to the new key. This is side stepped by stopping all (RX
and TX) aggregation sessions when replacing a PTK key and hardware key
offloading.
Stopping TX aggregation sessions avoids the need to get
the PNs (IVs) updated in frames prepared for the old key and
(re)transmitted after the switch to the new key. As a bonus it improves
the compatibility when the remote STA is not handling rekeys as it
should.
When using software crypto aggregation sessions are not stopped.
Mac80211 won't be able to decode the dangerous frames and discard them
without special handling.
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
[trim overly long rekey warning]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As explained in ieee80211_delayed_tailroom_dec(), during roam,
keys of the old AP will be destroyed and new keys will be
installed. Deletion of the old key causes
crypto_tx_tailroom_needed_cnt to go from 1 to 0 and the new key
installation causes a transition from 0 to 1.
Whenever crypto_tx_tailroom_needed_cnt transitions from 0 to 1,
we invoke synchronize_net(); the reason for doing this is to avoid
a race in the TX path as explained in increment_tailroom_need_count().
This synchronize_net() operation can be slow and can affect the station
roam time. To avoid this, decrementing the crypto_tx_tailroom_needed_cnt
is delayed for a while so that upon installation of new key the
transition would be from 1 to 2 instead of 0 to 1 and thereby
improving the roam time.
This is all correct for a STA iftype, but deferring the tailroom_needed
decrement for other iftypes may be unnecessary.
For example, let's consider the case of a 4-addr client connecting to
an AP for which AP_VLAN interface is also created, let the initial
value for tailroom_needed on the AP be 1.
* 4-addr client connects to the AP (AP: tailroom_needed = 1)
* AP will clear old keys, delay decrement of tailroom_needed count
* AP_VLAN is created, it takes the tailroom count from master
(AP_VLAN: tailroom_needed = 1, AP: tailroom_needed = 1)
* Install new key for the station, assume key is plumbed in the HW,
there won't be any change in tailroom_needed count on AP iface
* Delayed decrement of tailroom_needed count on AP
(AP: tailroom_needed = 0, AP_VLAN: tailroom_needed = 1)
Because of the delayed decrement on AP iface, tailroom_needed count goes
out of sync between AP(master iface) and AP_VLAN(slave iface) and
there would be unnecessary tailroom created for the packets going
through AP_VLAN iface.
Also, WARN_ONs were observed while trying to bring down the AP_VLAN
interface:
(warn_slowpath_common) (warn_slowpath_null+0x18/0x20)
(warn_slowpath_null) (ieee80211_free_keys+0x114/0x1e4)
(ieee80211_free_keys) (ieee80211_del_virtual_monitor+0x51c/0x850)
(ieee80211_del_virtual_monitor) (ieee80211_stop+0x30/0x3c)
(ieee80211_stop) (__dev_close_many+0x94/0xb8)
(__dev_close_many) (dev_close_many+0x5c/0xc8)
Restricting delayed decrement to station interface alone fixes the problem
and it makes sense to do so because delayed decrement is done to improve
roam time which is applicable only for client devices.
Signed-off-by: Manikanta Pubbisetty <mpubbise@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In the current implementation, mac80211 advertises the support of
AP_VLANs based on the driver's support for AP mode; it also
blocks encrypted AP_VLAN operation on devices advertising
SW_CRYPTO_CONTROL.
The implementation seems weird in it's current form and could be
often confusing, this is because there can be drivers advertising
both SW_CRYPTO_CONTROL and AP mode support (ex: ath10k) in which case
AP_VLAN will still be supported but only in open BSS and not in
secured BSS.
When SW_CRYPTO_CONTROL is enabled, it makes more sense if the decision
to support AP_VLANs is left to the driver. Mac80211 can then allow
AP_VLAN operations depending on the driver support.
Signed-off-by: Manikanta Pubbisetty <mpubbise@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Add a key flag to indicates that the device only needs
MIC space and not a real MIC.
In such cases, keep the MIC zeroed for ease of debug.
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
For the reinstall prevention, the code I had added compares the
whole key. It turns out though that iwlwifi firmware doesn't
provide the TKIP TX MIC key as it's not needed in client mode,
and thus the comparison will always return false.
For client mode, thus always zero out the TX MIC key part before
doing the comparison in order to avoid accepting the reinstall
of the key with identical encryption and RX MIC key, but not the
same TX MIC key (since the supplicant provides the real one.)
Fixes: fdf7cb4185 ("mac80211: accept key reinstall without changing anything")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Otherwise we risk leaking information via timing side channel.
Fixes: fdf7cb4185 ("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.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since drivers know nothing about AP_VLAN interfaces, trying to
call drv_set_default_unicast_key() just results in a warning
and no call to the driver. Avoid the warning by not calling the
driver for this on AP_VLAN interfaces.
This means that drivers that somehow need this call for AP mode
will fail to work properly in the presence of VLAN interfaces,
but the current drivers don't seem to use it, and mac80211 will
select and indicate the key - so drivers should be OK now.
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The regular RX path has a lot of code, but with a few
assumptions on the hardware it's possible to reduce the
amount of code significantly. Currently the assumptions
on the driver are the following:
* hardware/driver reordering buffer (if supporting aggregation)
* hardware/driver decryption & PN checking (if using encryption)
* hardware/driver did de-duplication
* hardware/driver did A-MSDU deaggregation
* AP_LINK_PS is used (in AP mode)
* no client powersave handling in mac80211 (in client mode)
of which some are actually checked per packet:
* de-duplication
* PN checking
* decryption
and additionally packets must
* not be A-MSDU (have been deaggregated by driver/device)
* be data packets
* not be fragmented
* be unicast
* have RFC 1042 header
Additionally dynamically we assume:
* no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
* station must be authorized
* 4-addr format not enabled
Some data needed for the RX path is cached in a new per-station
"fast_rx" structure, so that we only need to look at this and
the packet, no other memory when processing packets on the fast
RX path.
After doing the above per-packet checks, the data path collapses
down to a pretty simple conversion function taking advantage of
the data cached in the small fast_rx struct.
This should speed up the RX processing, and will make it easier
to reason about parallelizing RX (for which statistics will need
to be per-CPU still.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since the PNs of all the tx keys are now tracked in the public
part of the key struct (with atomic counter), we no longer
need these functions.
dvm and vt665{5,6} are currently the only users of these functions,
so update them accordingly.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some drivers/devices might want to set the IVs by
themselves (and still let mac80211 generate MMIC).
Specifically, this is needed when the device does
offloading at certain times, and the driver has
to make sure that the IVs of new tx frames (from
the host) are synchronized with IVs that were
potentially used during the offloading.
Similarly to CCMP, move the TX IVs of TKIP keys to the
public part of the key struct, and export a function
to add the IV right into the crypto header.
The public tx_pn field is defined as atomic64, so define
TKIP_PN_TO_IV16/32 helper macros to convert it to iv16/32
when needed.
Since the iv32 used for the p1k cache is taken
directly from the frame, we can safely remove
iv16/32 from being protected by tkip.txlock.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
add ieee80211_iter_keys_rcu() to iterate over uploaded
keys in atomic context (when rcu is locked)
The station removal code removes the keys only after
calling synchronize_net(), so it's not safe to iterate
the keys at this point (and postponing the actual key
deletion with call_rcu() might result in some
badly-ordered ops calls).
Add a flag to indicate a station is being removed,
and skip the configured keys if it's set.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Conflicts:
drivers/net/ethernet/mellanox/mlx4/main.c
net/packet/af_packet.c
Both conflicts were cases of simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Unfortunately, Michal's change to fix AP_VLAN crypto tailroom
caused a locking issue that was reported by lockdep, but only
in a few cases - the issue was a classic ABBA deadlock caused
by taking the mtx after the key_mtx, where normally they're
taken the other way around.
As the key mutex protects the field in question (I'm adding a
few annotations to make that clear) only the iteration needs
to be protected, but we can also iterate the interface list
with just RCU protection while holding the key mutex.
Fixes: f9dca80b98 ("mac80211: fix AP_VLAN crypto tailroom calculation")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As we're running out of hardware capability flags pretty quickly,
convert them to use the regular test_bit() style unsigned long
bitmaps.
This introduces a number of helper functions/macros to set and to
test the bits, along with new debugfs code.
The occurrences of an explicit __clear_bit() are intentional, the
drivers were never supposed to change their supported bits on the
fly. We should investigate changing this to be a per-frame flag.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Merge back net-next to get wireless driver changes (from Kalle)
to be able to create the API change across all trees properly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
For drivers supporting TSO or similar features, but that still have
PN assignment in software, there's a need to have some memory to
store the current PN value. As mac80211 already stores this and it's
somewhat complicated to add a per-driver area to the key struct (due
to the dynamic sizing thereof) it makes sense to just move the TX PN
to the keyconf, i.e. the public part of the key struct.
As TKIP is more complicated and we won't able to offload it in this
way right now (fast-xmit is skipped for TKIP unless the HW does it
all, and our hardware needs MMIC calculation in software) I've not
moved that for now - it's possible but requires exposing a lot of
the internal TKIP state.
As an bonus side effect, we can remove a lot of code by assuming the
keyseq struct has a certain layout - with BUILD_BUG_ON to verify it.
This might also improve performance, since now TX and RX no longer
share a cacheline.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Conflicts:
drivers/net/phy/amd-xgbe-phy.c
drivers/net/wireless/iwlwifi/Kconfig
include/net/mac80211.h
iwlwifi/Kconfig and mac80211.h were both trivial overlapping
changes.
The drivers/net/phy/amd-xgbe-phy.c file got removed in 'net-next' and
the bug fix that happened on the 'net' side is already integrated
into the rest of the amd-xgbe driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some splats I was seeing:
(a) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wep.c:102 ieee80211_wep_add_iv
(b) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:73 ieee80211_tx_h_michael_mic_add
(c) WARNING: CPU: 3 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:433 ieee80211_crypto_ccmp_encrypt
I've seen (a) and (b) with ath9k hw crypto and (c)
with ath9k sw crypto. All of them were related to
insufficient skb tailroom and I was able to
trigger these with ping6 program.
AP_VLANs may inherit crypto keys from parent AP.
This wasn't considered and yielded problems in
some setups resulting in inability to transmit
data because mac80211 wouldn't resize skbs when
necessary and subsequently drop some packets due
to insufficient tailroom.
For efficiency purposes don't inspect both AP_VLAN
and AP sdata looking for tailroom counter. Instead
update AP_VLAN tailroom counters whenever their
master AP tailroom counter changes.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Currently, a cipher scheme can advertise an arbitrarily long
sequence counter, but mac80211 only supports up to 16 bytes
and the initial value from userspace will be truncated.
Fix two things:
* don't allow the driver to register anything longer than
the 16 bytes that mac80211 reserves space for
* require userspace to specify a starting value with the
correct length (or none at all)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
For ciphers not supported by mac80211, the function currently
doesn't return any PN data. Fix this by extending the driver's
get_key_seq() a little more to allow moving arbitrary PN data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to speed up mac80211's TX path, add the "fast-xmit" cache
that will cache the data frame 802.11 header and other data to be
able to build the frame more quickly. This cache is rebuilt when
external triggers imply changes, but a lot of the checks done per
packet today are simplified away to the check for the cache.
There's also a more detailed description in the code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a key is installed using a cipher scheme, set a new
internal key flag (KEY_FLAG_CIPHER_SCHEME) on it, to allow
distinguishing such keys more easily.
In particular, use this flag on the TX path instead of
testing the sta->cipher_scheme pointer, as the station is
NULL for broad-/multicast message, and use the key's iv_len
instead of the cipher scheme information.
Signed-off-by: Cedric Izoard <cedric.izoard@ceva-dsp.com>
[add missing documentation, rewrite commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure BIP-GMAC-128 and BIP-GMAC-256 to the
driver and also use software-implementation within mac80211 when the
driver does not support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure BIP-CMAC-256 to the driver and also
use software-implementation within mac80211 when the driver does not
support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure CCMP-256 to the driver and also use
software-implementation within mac80211 when the driver does not support
this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[squash ccmp256 -> mic_len argument change]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure GCMP and GCMP-256 to the driver and
also use software-implementation within mac80211 when the driver does
not support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[remove a spurious newline]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some drivers unfortunately cannot support software crypto, but
mac80211 currently assumes that they do.
This has the issue that if the hardware enabling fails for some
reason, the software fallback is used, which won't work. This
clearly isn't desirable, the error should be reported and the
key setting refused.
Support this in mac80211 by allowing drivers to set a new HW
flag IEEE80211_HW_SW_CRYPTO_CONTROL, in which case mac80211 will
only allow software fallback if the set_key() method returns 1.
The driver will also need to advertise supported cipher suites
so that mac80211 doesn't advertise any (future) software ciphers
that the driver can't actually do.
While at it, to make it easier to support this, refactor the
ieee80211_init_cipher_suites() code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When hw acceleration is enabled, the GENERATE_IV or PUT_IV_SPACE flags
only require headroom space. Therefore, the tailroom-needed counter can
safely be decremented for most drivers.
The older incarnation of this patch (ca34e3b5) assumed that the above
holds true for all drivers. As reported by Christopher Chavez and
researched by Christian Lamparter and Larry Finger, this isn't a valid
assumption for p54 and cw1200.
Drivers that still require tailroom for ICV/MIC even when HW encryption
is enabled can use IEEE80211_KEY_FLAG_RESERVE_TAILROOM to indicate it.
Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Cc: Christopher Chavez <chrischavez@gmx.us>
Cc: Christian Lamparter <chunkeey@googlemail.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This reverts commit ca34e3b5c8.
It turns out that the p54 and cw2100 drivers assume that there's
tailroom even when they don't say they really need it. However,
there's currently no way for them to explicitly say they do need
it, so for now revert this.
This fixes https://bugzilla.kernel.org/show_bug.cgi?id=90331.
Cc: stable@vger.kernel.org
Fixes: ca34e3b5c8 ("mac80211: Fix accounting of the tailroom-needed counter")
Reported-by: Christopher Chavez <chrischavez@gmx.us>
Bisected-by: Larry Finger <Larry.Finger@lwfinger.net>
Debugged-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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.
Cc: stable@vger.kernel.org
Fixes: e31b82136d ("cfg80211/mac80211: allow per-station GTKs")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a key is tainted during resume, it is no longer programmed
into the device; however, it's uploaded flag may (will) be set.
Clear the flag when not programming it because it's tainted to
avoid attempting to remove it again later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When freeing the key, clear the memory to avoid having the
key material stick around in memory "forever".
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Our legal structure changed at some point (see wikipedia), but
we forgot to immediately switch over to the new copyright
notice.
For files that we have modified in the time since the change,
add the proper copyright notice now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When hw acceleration is enabled, the GENERATE_IV or PUT_IV_SPACE flags
will only require headroom space. Consequently, the tailroom-needed
counter can safely be decremented.
Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
sdata can't be NULL, and key being NULL is really not possible
unless the code is modified.
The sdata check made a static analyze (klocwork) unhappy because
we would get pointer to local (sdata->local) and only then check
if sdata is non-NULL.
Signed-off-by: Eytan Lifshitz <eytan.lifshitz@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
[remove !key check as well]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
These BUG_ON statements should never trigger, but in the unlikely
event that somebody does manage don't stop everything but simply
exit the code path with an error.
Leave the one BUG_ON where changing it would result in a NULL
pointer dereference.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When the AP interface is stopped, free all AP and VLAN keys at
once to only require synchronize_net() once. Since that does
synchronize_net(), also move two such calls into the function
(using the new force_synchronize parameter) to avoid doing it
twice.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no reason to do this inside the sta key removal
since the keys can only be reached through the sta (and
not by the driver at all) so once the sta can no longer
be reached, the keys are safe.
This will allow further optimisation opportunities with
multiple stations.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This adds generic cipher scheme support to mac80211, such schemes
are fully under control by the driver. On hw registration drivers
may specify additional HW ciphers with a scheme how these ciphers
have to be handled by mac80211 TX/RR. A cipher scheme specifies a
cipher suite value, a size of the security header to be added to
or stripped from frames and how the PN is to be verified on RX.
Signed-off-by: Max Stepanov <Max.Stepanov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no code calling ieee80211_key_replace() with both
arguments NULL and it wouldn't make sense, but in the
interest of maintainability add a warning for it. As a
side effect, this also shuts up a smatch warning.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
No need for ERR_PTR(PTR_ERR()) since there's ERR_CAST, use it.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to be able to (securely) keep connections alive after
the system was suspended for WoWLAN, we need some additional
APIs. We already have API (ieee80211_gtk_rekey_notify) to tell
wpa_supplicant about the new replay counter if GTK rekeying
was done by the device while the host was asleep, but that's
not sufficient.
If GTK rekeying wasn't done, we need to tell the host about
sequence counters for the GTK (and PTK regardless of rekeying)
that was used while asleep, add ieee80211_set_key_rx_seq() for
that.
If GTK rekeying was done, then we need to be able to disable
the old keys (with ieee80211_remove_key()) and allocate the
new GTK key(s) in mac80211 (with ieee80211_gtk_rekey_add()).
If protocol offload (e.g. ARP) is implemented, then also the
TX sequence counter for the PTK must be updated, using the new
ieee80211_set_key_tx_seq() function.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211 and the Intel drivers all define crypto
constants, move them to ieee80211.h instead.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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>
