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2015-05-20mac80211: fix AP_VLAN crypto tailroom calculationMichal Kazior
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>
2015-03-17mac80211: Get IV len from key conf and not cipher schemeCedric Izoard
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>
2015-01-27mac80111: Add BIP-GMAC-128 and BIP-GMAC-256 ciphersJouni Malinen
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>
2015-01-27mac80111: Add BIP-CMAC-256 cipherJouni Malinen
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>
2015-01-27mac80111: Add CCMP-256 cipherJouni Malinen
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>
2015-01-27mac80111: Add GCMP and GCMP-256 ciphersJouni Malinen
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>
2015-01-22mac80211: allow drivers to control software cryptoJohannes Berg
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>
2015-01-07mac80211: Re-fix accounting of the tailroom-needed counterIdo Yariv
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>
2015-01-05Revert "mac80211: Fix accounting of the tailroom-needed counter"Johannes Berg
This reverts commit ca34e3b5c808385b175650605faa29e71e91991b. 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: ca34e3b5c808 ("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>
2014-12-17mac80211: free management frame keys when removing stationJohannes Berg
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: e31b82136d1a ("cfg80211/mac80211: allow per-station GTKs") Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-10-22mac80211: don't remove tainted keys after not programmingJohannes Berg
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>
2014-09-11mac80211: clear key material when freeing keysJohannes Berg
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>
2014-09-05mac80211: add Intel Mobile Communications copyrightJohannes Berg
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>
2014-08-26mac80211: Fix accounting of the tailroom-needed counterIdo Yariv
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>
2014-07-21mac80211: remove useless NULL checksEytan Lifshitz
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>
2014-04-29mac80211: remove BUG_ON usageJohannes Berg
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>
2013-12-16mac80211: free all AP/VLAN keys at onceJohannes Berg
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>
2013-12-16mac80211: move synchronize_net() before sta key removalJohannes Berg
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>
2013-11-25mac80211: add generic cipher scheme supportMax Stepanov
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>
2013-11-25mac80211: verify ieee80211_key_replace() argumentsJohannes Berg
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>
2013-09-26mac80211: use ERR_CAST()Johannes Berg
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>
2013-08-16mac80211: add APIs to allow keeping connections after WoWLANJohannes Berg
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>
2013-05-16wireless: move crypto constants to ieee80211.hJohannes Berg
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>
2013-03-11mac80211: batch key free synchronize_net()Johannes Berg
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>
2013-03-11mac80211: remove underscores from some key functionsJohannes Berg
Some key function don't exist without underscores, so remove the underscores from those. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-03-11mac80211: clean up key freeing a bitJohannes Berg
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>
2013-03-06mac80211: defer tailroom counter manipulation when roamingJohannes Berg
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>
2013-03-06mac80211: remove IEEE80211_KEY_FLAG_WMM_STAJohannes Berg
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>
2013-03-06mac80211: cleanup generic suspend/resume proceduresStanislaw Gruszka
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>
2013-01-18mac80211: add op to configure default key idYoni Divinsky
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>
2012-11-19mac80211: introduce IEEE80211_NUM_TIDS and use itJohannes Berg
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>
2012-11-19mac80211: use CMAC_PN_LENJohannes Berg
Instead of hardcoding its value (6), use the constant. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-06mac80211: use synchronize_net() on key destroyingEliad Peller
__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>
2012-07-09mac80211: remove ieee80211_key_removedJohannes Berg
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>
2012-06-24mac80211: clean up debuggingJohannes Berg
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>
2012-02-27mac80211: clean up asm/unaligned.h inclusionJohannes Berg
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>
2012-02-06mac80211: dont program keys for stations not uploadedJohannes Berg
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>
2012-02-06mac80211: simplify AP_VLAN handlingJohannes Berg
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>
2011-11-17Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem Conflicts: include/net/bluetooth/bluetooth.h
2011-11-08mac80211: support adding IV-room in the skb for CCMP keysArik Nemtsov
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>
2011-10-31net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modulesPaul Gortmaker
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>
2011-09-30mac80211: optimise station flagsJohannes Berg
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>
2011-07-15mac80211: let key iteration get keys in install orderJohannes Berg
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>
2011-07-08mac80211: allow drivers to access key sequence counterJohannes Berg
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>
2011-07-08mac80211: fix TKIP races, make API easier to useJohannes Berg
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>
2011-07-06mac80211: support GTK rekey offloadJohannes Berg
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>
2011-07-06mac80211: allow driver to iterate keysJohannes Berg
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>
2011-07-05mac80211: Skip tailroom reservation for full HW-crypto devices with race fixYogesh Ashok Powar
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>
2011-06-06Revert "mac80211: Skip tailroom reservation for full HW-crypto devices"John W. Linville
This reverts commit aac6af5534fade2b18682a0b9efad1a6c04c34c6. Conflicts: net/mac80211/key.c That commit has a race that causes a warning, as documented in the thread here: http://marc.info/?l=linux-wireless&m=130717684914101&w=2 Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-16mac80211: sparse RCU annotationsJohannes Berg
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>