linux/net/mac80211/key.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2013-2014 Intel Mobile Communications GmbH
* Copyright 2015-2017 Intel Deutschland GmbH
* Copyright 2018-2020, 2022-2023 Intel Corporation
*/
#include <crypto/utils.h>
[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>
2007-08-28 21:01:55 +00:00
#include <linux/if_ether.h>
#include <linux/etherdevice.h>
#include <linux/list.h>
[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>
2007-09-14 15:10:24 +00:00
#include <linux/rcupdate.h>
#include <linux/rtnetlink.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "debugfs_key.h"
#include "aes_ccm.h"
#include "aes_cmac.h"
#include "aes_gmac.h"
#include "aes_gcm.h"
[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>
2007-08-28 21:01:55 +00:00
/**
* DOC: Key handling basics
[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>
2007-08-28 21:01:55 +00:00
*
* Key handling in mac80211 is done based on per-interface (sub_if_data)
* keys and per-station keys. Since each station belongs to an interface,
* each station key also belongs to that interface.
*
* Hardware acceleration is done on a best-effort basis for algorithms
* that are implemented in software, for each key the hardware is asked
* to enable that key for offloading but if it cannot do that the key is
* simply kept for software encryption (unless it is for an algorithm
* that isn't implemented in software).
* There is currently no way of knowing whether a key is handled in SW
* or HW except by looking into debugfs.
[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>
2007-08-28 21:01:55 +00:00
*
* All key management is internally protected by a mutex. Within all
* other parts of mac80211, key references are, just as STA structure
* references, protected by RCU. Note, however, that some things are
* unprotected, namely the key->sta dereferences within the hardware
* acceleration functions. This means that sta_info_destroy() must
* remove the key which waits for an RCU grace period.
[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>
2007-08-28 21:01:55 +00:00
*/
static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
static void assert_key_lock(struct ieee80211_local *local)
{
lockdep_assert_held(&local->key_mtx);
}
static void
update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
{
struct ieee80211_sub_if_data *vlan;
if (sdata->vif.type != NL80211_IFTYPE_AP)
return;
/* crypto_tx_tailroom_needed_cnt is protected by this */
assert_key_lock(sdata->local);
rcu_read_lock();
list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)
vlan->crypto_tx_tailroom_needed_cnt += delta;
rcu_read_unlock();
}
static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
{
/*
* When this count is zero, SKB resizing for allocating tailroom
* for IV or MMIC is skipped. But, this check has created two race
* cases in xmit path while transiting from zero count to one:
*
* 1. SKB resize was skipped because no key was added but just before
* the xmit key is added and SW encryption kicks off.
*
* 2. SKB resize was skipped because all the keys were hw planted but
* just before xmit one of the key is deleted and SW encryption kicks
* off.
*
* In both the above case SW encryption will find not enough space for
* tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
*
* Solution has been explained at
* http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
*/
assert_key_lock(sdata->local);
update_vlan_tailroom_need_count(sdata, 1);
if (!sdata->crypto_tx_tailroom_needed_cnt++) {
/*
* Flush all XMIT packets currently using HW encryption or no
* encryption at all if the count transition is from 0 -> 1.
*/
synchronize_net();
}
}
static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
int delta)
{
assert_key_lock(sdata->local);
WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
update_vlan_tailroom_need_count(sdata, -delta);
sdata->crypto_tx_tailroom_needed_cnt -= delta;
}
static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
[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>
2007-08-28 21:01:55 +00:00
{
struct ieee80211_sub_if_data *sdata = key->sdata;
struct sta_info *sta;
int ret = -EOPNOTSUPP;
[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>
2007-08-28 21:01:55 +00:00
might_sleep();
if (key->flags & KEY_FLAG_TAINTED) {
/* If we get here, it's during resume and the key is
* tainted so shouldn't be used/programmed any more.
* However, its flags may still indicate that it was
* programmed into the device (since we're in resume)
* so clear that flag now to avoid trying to remove
* it again later.
*/
if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE &&
!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
increment_tailroom_need_count(sdata);
key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
return -EINVAL;
}
if (!key->local->ops->set_key)
goto out_unsupported;
[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>
2007-08-28 21:01:55 +00:00
assert_key_lock(key->local);
sta = key->sta;
/*
* If this is a per-STA GTK, check if it
* is supported; if not, return.
*/
if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
!ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))
goto out_unsupported;
if (sta && !sta->uploaded)
goto out_unsupported;
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
/*
* The driver doesn't know anything about VLAN interfaces.
* Hence, don't send GTKs for VLAN interfaces to the driver.
*/
if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
ret = 1;
goto out_unsupported;
}
}
[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>
2007-08-28 21:01:55 +00:00
if (key->conf.link_id >= 0 && sdata->vif.active_links &&
!(sdata->vif.active_links & BIT(key->conf.link_id)))
return 0;
ret = drv_set_key(key->local, SET_KEY, sdata,
sta ? &sta->sta : NULL, &key->conf);
[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>
2007-08-28 21:01:55 +00:00
if (!ret) {
[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>
2007-08-28 21:01:55 +00:00
key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
decrease_tailroom_need_count(sdata, 1);
WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));
return 0;
}
[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>
2007-08-28 21:01:55 +00:00
if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
sdata_err(sdata,
"failed to set key (%d, %pM) to hardware (%d)\n",
key->conf.keyidx,
sta ? sta->sta.addr : bcast_addr, ret);
out_unsupported:
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104:
case WLAN_CIPHER_SUITE_TKIP:
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
/* all of these we can do in software - if driver can */
if (ret == 1)
return 0;
if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))
return -EINVAL;
return 0;
default:
return -EINVAL;
}
[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>
2007-08-28 21:01:55 +00:00
}
static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
{
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
[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>
2007-08-28 21:01:55 +00:00
int ret;
might_sleep();
if (!key || !key->local->ops->set_key)
[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>
2007-08-28 21:01:55 +00:00
return;
assert_key_lock(key->local);
if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
[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>
2007-08-28 21:01:55 +00:00
return;
sta = key->sta;
sdata = key->sdata;
if (key->conf.link_id >= 0 && sdata->vif.active_links &&
!(sdata->vif.active_links & BIT(key->conf.link_id)))
return;
if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
increment_tailroom_need_count(sdata);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
ret = drv_set_key(key->local, DISABLE_KEY, sdata,
sta ? &sta->sta : NULL, &key->conf);
[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>
2007-08-28 21:01:55 +00:00
if (ret)
sdata_err(sdata,
"failed to remove key (%d, %pM) from hardware (%d)\n",
key->conf.keyidx,
sta ? sta->sta.addr : bcast_addr, ret);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
}
[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>
2007-08-28 21:01:55 +00:00
static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force)
{
struct sta_info *sta = key->sta;
struct ieee80211_local *local = key->local;
assert_key_lock(local);
set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION);
sta->ptk_idx = key->conf.keyidx;
if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
ieee80211_check_fast_xmit(sta);
return 0;
}
int ieee80211_set_tx_key(struct ieee80211_key *key)
{
return _ieee80211_set_tx_key(key, false);
}
static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
struct ieee80211_key *new)
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
{
struct ieee80211_local *local = new->local;
struct sta_info *sta = new->sta;
int i;
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
assert_key_lock(local);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) {
/* Extended Key ID key install, initial one or rekey */
if (sta->ptk_idx != INVALID_PTK_KEYIDX &&
!ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) {
/* Aggregation Sessions with Extended Key ID must not
* mix MPDUs with different keyIDs within one A-MPDU.
* Tear down running Tx aggregation sessions and block
* new Rx/Tx aggregation requests during rekey to
* ensure there are no A-MPDUs when the driver is not
* supporting A-MPDU key borders. (Blocking Tx only
* would be sufficient but WLAN_STA_BLOCK_BA gets the
* job done for the few ms we need it.)
*/
set_sta_flag(sta, WLAN_STA_BLOCK_BA);
mutex_lock(&sta->ampdu_mlme.mtx);
for (i = 0; i < IEEE80211_NUM_TIDS; i++)
___ieee80211_stop_tx_ba_session(sta, i,
AGG_STOP_LOCAL_REQUEST);
mutex_unlock(&sta->ampdu_mlme.mtx);
}
} else if (old) {
/* Rekey without Extended Key ID.
* Aggregation sessions are OK when running on SW crypto.
* A broken remote STA may cause issues not observed with HW
* crypto, though.
*/
if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
return;
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
/* Stop Tx till we are on the new key */
old->flags |= KEY_FLAG_TAINTED;
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
ieee80211_clear_fast_xmit(sta);
if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
set_sta_flag(sta, WLAN_STA_BLOCK_BA);
ieee80211_sta_tear_down_BA_sessions(sta,
AGG_STOP_LOCAL_REQUEST);
}
if (!wiphy_ext_feature_isset(local->hw.wiphy,
NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) {
pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.",
sta->sta.addr);
/* Flushing the driver queues *may* help prevent
* the clear text leaks and freezes.
*/
ieee80211_flush_queues(local, old->sdata, false);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
}
}
}
static void __ieee80211_set_default_key(struct ieee80211_link_data *link,
int idx, bool uni, bool multi)
{
struct ieee80211_sub_if_data *sdata = link->sdata;
struct ieee80211_key *key = NULL;
assert_key_lock(sdata->local);
if (idx >= 0 && idx < NUM_DEFAULT_KEYS) {
key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
if (!key)
key = key_mtx_dereference(sdata->local, link->gtk[idx]);
}
if (uni) {
rcu_assign_pointer(sdata->default_unicast_key, key);
ieee80211_check_fast_xmit_iface(sdata);
if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
drv_set_default_unicast_key(sdata->local, sdata, idx);
}
if (multi)
rcu_assign_pointer(link->default_multicast_key, key);
ieee80211_debugfs_key_update_default(sdata);
}
void ieee80211_set_default_key(struct ieee80211_link_data *link, int idx,
bool uni, bool multi)
{
mutex_lock(&link->sdata->local->key_mtx);
__ieee80211_set_default_key(link, idx, uni, multi);
mutex_unlock(&link->sdata->local->key_mtx);
}
static void
__ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link, int idx)
{
struct ieee80211_sub_if_data *sdata = link->sdata;
struct ieee80211_key *key = NULL;
assert_key_lock(sdata->local);
if (idx >= NUM_DEFAULT_KEYS &&
idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
key = key_mtx_dereference(sdata->local, link->gtk[idx]);
rcu_assign_pointer(link->default_mgmt_key, key);
ieee80211_debugfs_key_update_default(sdata);
}
void ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link,
int idx)
{
mutex_lock(&link->sdata->local->key_mtx);
__ieee80211_set_default_mgmt_key(link, idx);
mutex_unlock(&link->sdata->local->key_mtx);
}
static void
__ieee80211_set_default_beacon_key(struct ieee80211_link_data *link, int idx)
{
struct ieee80211_sub_if_data *sdata = link->sdata;
struct ieee80211_key *key = NULL;
assert_key_lock(sdata->local);
if (idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS &&
idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
NUM_DEFAULT_BEACON_KEYS)
key = key_mtx_dereference(sdata->local, link->gtk[idx]);
rcu_assign_pointer(link->default_beacon_key, key);
ieee80211_debugfs_key_update_default(sdata);
}
void ieee80211_set_default_beacon_key(struct ieee80211_link_data *link,
int idx)
{
mutex_lock(&link->sdata->local->key_mtx);
__ieee80211_set_default_beacon_key(link, idx);
mutex_unlock(&link->sdata->local->key_mtx);
}
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
struct ieee80211_link_data *link,
struct sta_info *sta,
bool pairwise,
struct ieee80211_key *old,
struct ieee80211_key *new)
{
struct link_sta_info *link_sta = sta ? &sta->deflink : NULL;
int link_id;
int idx;
int ret = 0;
bool defunikey, defmultikey, defmgmtkey, defbeaconkey;
bool is_wep;
/* caller must provide at least one old/new */
if (WARN_ON(!new && !old))
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
return 0;
if (new) {
idx = new->conf.keyidx;
is_wep = new->conf.cipher == WLAN_CIPHER_SUITE_WEP40 ||
new->conf.cipher == WLAN_CIPHER_SUITE_WEP104;
link_id = new->conf.link_id;
} else {
idx = old->conf.keyidx;
is_wep = old->conf.cipher == WLAN_CIPHER_SUITE_WEP40 ||
old->conf.cipher == WLAN_CIPHER_SUITE_WEP104;
link_id = old->conf.link_id;
}
if (WARN(old && old->conf.link_id != link_id,
"old link ID %d doesn't match new link ID %d\n",
old->conf.link_id, link_id))
return -EINVAL;
if (link_id >= 0) {
if (!link) {
link = sdata_dereference(sdata->link[link_id], sdata);
if (!link)
return -ENOLINK;
}
if (sta) {
link_sta = rcu_dereference_protected(sta->link[link_id],
lockdep_is_held(&sta->local->hw.wiphy->mtx));
if (!link_sta)
return -ENOLINK;
}
} else {
link = &sdata->deflink;
}
if ((is_wep || pairwise) && idx >= NUM_DEFAULT_KEYS)
return -EINVAL;
WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
if (new && sta && pairwise) {
/* Unicast rekey needs special handling. With Extended Key ID
* old is still NULL for the first rekey.
*/
ieee80211_pairwise_rekey(old, new);
}
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
if (old) {
if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
ieee80211_key_disable_hw_accel(old);
if (new)
ret = ieee80211_key_enable_hw_accel(new);
}
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
} else {
if (!new->local->wowlan) {
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
ret = ieee80211_key_enable_hw_accel(new);
} else {
assert_key_lock(new->local);
new->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
}
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
}
if (ret)
return ret;
if (new)
list_add_tail_rcu(&new->list, &sdata->key_list);
if (sta) {
if (pairwise) {
rcu_assign_pointer(sta->ptk[idx], new);
if (new &&
!(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX))
_ieee80211_set_tx_key(new, true);
} else {
rcu_assign_pointer(link_sta->gtk[idx], new);
}
/* Only needed for transition from no key -> key.
* Still triggers unnecessary when using Extended Key ID
* and installing the second key ID the first time.
*/
if (new && !old)
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
ieee80211_check_fast_rx(sta);
} else {
defunikey = old &&
old == key_mtx_dereference(sdata->local,
sdata->default_unicast_key);
defmultikey = old &&
old == key_mtx_dereference(sdata->local,
link->default_multicast_key);
defmgmtkey = old &&
old == key_mtx_dereference(sdata->local,
link->default_mgmt_key);
defbeaconkey = old &&
old == key_mtx_dereference(sdata->local,
link->default_beacon_key);
if (defunikey && !new)
__ieee80211_set_default_key(link, -1, true, false);
if (defmultikey && !new)
__ieee80211_set_default_key(link, -1, false, true);
if (defmgmtkey && !new)
__ieee80211_set_default_mgmt_key(link, -1);
if (defbeaconkey && !new)
__ieee80211_set_default_beacon_key(link, -1);
if (is_wep || pairwise)
rcu_assign_pointer(sdata->keys[idx], new);
else
rcu_assign_pointer(link->gtk[idx], new);
if (defunikey && new)
__ieee80211_set_default_key(link, new->conf.keyidx,
true, false);
if (defmultikey && new)
__ieee80211_set_default_key(link, new->conf.keyidx,
false, true);
if (defmgmtkey && new)
__ieee80211_set_default_mgmt_key(link,
new->conf.keyidx);
if (defbeaconkey && new)
__ieee80211_set_default_beacon_key(link,
new->conf.keyidx);
}
if (old)
list_del_rcu(&old->list);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
return 0;
[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>
2007-08-28 21:01:55 +00:00
}
struct ieee80211_key *
ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
const u8 *key_data,
size_t seq_len, const u8 *seq)
{
struct ieee80211_key *key;
int i, j, err;
if (WARN_ON(idx < 0 ||
idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
NUM_DEFAULT_BEACON_KEYS))
return ERR_PTR(-EINVAL);
[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>
2007-08-28 21:01:55 +00:00
key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
if (!key)
return ERR_PTR(-ENOMEM);
[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>
2007-08-28 21:01:55 +00:00
/*
* Default to software encryption; we'll later upload the
* key to the hardware if possible.
*/
key->conf.flags = 0;
key->flags = 0;
key->conf.link_id = -1;
key->conf.cipher = cipher;
[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>
2007-08-28 21:01:55 +00:00
key->conf.keyidx = idx;
key->conf.keylen = key_len;
switch (cipher) {
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104:
key->conf.iv_len = IEEE80211_WEP_IV_LEN;
key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
break;
case WLAN_CIPHER_SUITE_TKIP:
key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
if (seq) {
for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
key->u.tkip.rx[i].iv32 =
get_unaligned_le32(&seq[2]);
key->u.tkip.rx[i].iv16 =
get_unaligned_le16(seq);
}
}
spin_lock_init(&key->u.tkip.txlock);
break;
case WLAN_CIPHER_SUITE_CCMP:
key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
if (seq) {
for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
key->u.ccmp.rx_pn[i][j] =
seq[IEEE80211_CCMP_PN_LEN - j - 1];
}
[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>
2007-08-28 21:01:55 +00:00
/*
* Initialize AES key state here as an optimization so that
* it does not need to be initialized for every packet.
*/
key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
key_data, key_len, IEEE80211_CCMP_MIC_LEN);
if (IS_ERR(key->u.ccmp.tfm)) {
err = PTR_ERR(key->u.ccmp.tfm);
kfree(key);
return ERR_PTR(err);
}
break;
case WLAN_CIPHER_SUITE_CCMP_256:
key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
key->u.ccmp.rx_pn[i][j] =
seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
/* Initialize AES key state here as an optimization so that
* it does not need to be initialized for every packet.
*/
key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
if (IS_ERR(key->u.ccmp.tfm)) {
err = PTR_ERR(key->u.ccmp.tfm);
kfree(key);
return ERR_PTR(err);
[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>
2007-08-28 21:01:55 +00:00
}
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
key->conf.iv_len = 0;
if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
key->conf.icv_len = sizeof(struct ieee80211_mmie);
else
key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
if (seq)
for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
key->u.aes_cmac.rx_pn[j] =
seq[IEEE80211_CMAC_PN_LEN - j - 1];
/*
* Initialize AES key state here as an optimization so that
* it does not need to be initialized for every packet.
*/
key->u.aes_cmac.tfm =
ieee80211_aes_cmac_key_setup(key_data, key_len);
if (IS_ERR(key->u.aes_cmac.tfm)) {
err = PTR_ERR(key->u.aes_cmac.tfm);
kfree(key);
return ERR_PTR(err);
}
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
key->conf.iv_len = 0;
key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
if (seq)
for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
key->u.aes_gmac.rx_pn[j] =
seq[IEEE80211_GMAC_PN_LEN - j - 1];
/* Initialize AES key state here as an optimization so that
* it does not need to be initialized for every packet.
*/
key->u.aes_gmac.tfm =
ieee80211_aes_gmac_key_setup(key_data, key_len);
if (IS_ERR(key->u.aes_gmac.tfm)) {
err = PTR_ERR(key->u.aes_gmac.tfm);
kfree(key);
return ERR_PTR(err);
}
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
key->u.gcmp.rx_pn[i][j] =
seq[IEEE80211_GCMP_PN_LEN - j - 1];
/* Initialize AES key state here as an optimization so that
* it does not need to be initialized for every packet.
*/
key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
key_len);
if (IS_ERR(key->u.gcmp.tfm)) {
err = PTR_ERR(key->u.gcmp.tfm);
kfree(key);
return ERR_PTR(err);
}
break;
}
memcpy(key->conf.key, key_data, key_len);
INIT_LIST_HEAD(&key->list);
return key;
}
[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>
2007-08-28 21:01:55 +00:00
static void ieee80211_key_free_common(struct ieee80211_key *key)
{
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
ieee80211_aes_key_free(key->u.ccmp.tfm);
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
break;
}
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 06:18:13 +00:00
kfree_sensitive(key);
}
static void __ieee80211_key_destroy(struct ieee80211_key *key,
bool delay_tailroom)
{
if (key->local) {
struct ieee80211_sub_if_data *sdata = key->sdata;
ieee80211_debugfs_key_remove(key);
if (delay_tailroom) {
/* see ieee80211_delayed_tailroom_dec */
sdata->crypto_tx_tailroom_pending_dec++;
wiphy_delayed_work_queue(sdata->local->hw.wiphy,
&sdata->dec_tailroom_needed_wk,
HZ / 2);
} else {
decrease_tailroom_need_count(sdata, 1);
}
}
ieee80211_key_free_common(key);
}
static void ieee80211_key_destroy(struct ieee80211_key *key,
bool delay_tailroom)
{
if (!key)
return;
/*
* Synchronize so the TX path and rcu key iterators
* can no longer be using this key before we free/remove it.
*/
synchronize_net();
__ieee80211_key_destroy(key, delay_tailroom);
}
void ieee80211_key_free_unused(struct ieee80211_key *key)
{
WARN_ON(key->sdata || key->local);
ieee80211_key_free_common(key);
}
static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
struct ieee80211_key *old,
struct ieee80211_key *new)
{
u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
u8 *tk_old, *tk_new;
if (!old || new->conf.keylen != old->conf.keylen)
return false;
tk_old = old->conf.key;
tk_new = new->conf.key;
/*
* In station mode, don't compare the TX MIC key, as it's never used
* and offloaded rekeying may not care to send it to the host. This
* is the case in iwlwifi, for example.
*/
if (sdata->vif.type == NL80211_IFTYPE_STATION &&
new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
new->conf.keylen == WLAN_KEY_LEN_TKIP &&
!(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
tk_old = tkip_old;
tk_new = tkip_new;
}
return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
}
int ieee80211_key_link(struct ieee80211_key *key,
struct ieee80211_link_data *link,
struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = link->sdata;
static atomic_t key_color = ATOMIC_INIT(0);
struct ieee80211_key *old_key = NULL;
mac80211: restrict delayed tailroom needed decrement 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>
2018-07-10 11:18:27 +00:00
int idx = key->conf.keyidx;
bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
/*
* We want to delay tailroom updates only for station - in that
* case it helps roaming speed, but in other cases it hurts and
* can cause warnings to appear.
*/
bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;
int ret = -EOPNOTSUPP;
mutex_lock(&sdata->local->key_mtx);
if (sta && pairwise) {
struct ieee80211_key *alt_key;
old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]);
/* The rekey code assumes that the old and new key are using
* the same cipher. Enforce the assumption for pairwise keys.
*/
if ((alt_key && alt_key->conf.cipher != key->conf.cipher) ||
(old_key && old_key->conf.cipher != key->conf.cipher))
goto out;
} else if (sta) {
struct link_sta_info *link_sta = &sta->deflink;
int link_id = key->conf.link_id;
if (link_id >= 0) {
link_sta = rcu_dereference_protected(sta->link[link_id],
lockdep_is_held(&sta->local->hw.wiphy->mtx));
if (!link_sta) {
ret = -ENOLINK;
goto out;
}
}
old_key = key_mtx_dereference(sdata->local, link_sta->gtk[idx]);
} else {
if (idx < NUM_DEFAULT_KEYS)
old_key = key_mtx_dereference(sdata->local,
sdata->keys[idx]);
if (!old_key)
old_key = key_mtx_dereference(sdata->local,
link->gtk[idx]);
}
/* Non-pairwise keys must also not switch the cipher on rekey */
if (!pairwise) {
if (old_key && old_key->conf.cipher != key->conf.cipher)
goto out;
}
/*
* Silently accept key re-installation without really installing the
* new version of the key to avoid nonce reuse or replay issues.
*/
if (ieee80211_key_identical(sdata, old_key, key)) {
ieee80211_key_free_unused(key);
ret = 0;
goto out;
}
key->local = sdata->local;
key->sdata = sdata;
key->sta = sta;
/*
* Assign a unique ID to every key so we can easily prevent mixed
* key and fragment cache attacks.
*/
key->color = atomic_inc_return(&key_color);
increment_tailroom_need_count(sdata);
ret = ieee80211_key_replace(sdata, link, sta, pairwise, old_key, key);
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
if (!ret) {
ieee80211_debugfs_key_add(key);
ieee80211_key_destroy(old_key, delay_tailroom);
} else {
mac80211: Fix PTK rekey freezes and clear text leak 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>
2018-08-31 13:00:38 +00:00
ieee80211_key_free(key, delay_tailroom);
}
out:
mutex_unlock(&sdata->local->key_mtx);
return ret;
}
void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
{
if (!key)
return;
/*
* Replace key with nothingness if it was ever used.
*/
if (key->sdata)
ieee80211_key_replace(key->sdata, NULL, key->sta,
key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
key, NULL);
ieee80211_key_destroy(key, delay_tailroom);
}
[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>
2007-09-14 15:10:24 +00:00
mac80211: clear crypto tx tailroom counter upon keys enable In case we got a fw restart while roaming from encrypted AP to non-encrypted one, we might end up with hitting a warning on the pending counter crypto_tx_tailroom_pending_dec having a non-zero value. The following comment taken from net/mac80211/key.c explains the rational for the delayed tailroom needed: /* * The reason for the delayed tailroom needed decrementing is to * make roaming faster: during roaming, all keys are first deleted * and then new keys are installed. The first new key causes the * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes * the cost of synchronize_net() (which can be slow). Avoid this * by deferring the crypto_tx_tailroom_needed_cnt decrementing on * key removal for a while, so if we roam the value is larger than * zero and no 0->1 transition happens. * * The cost is that if the AP switching was from an AP with keys * to one without, we still allocate tailroom while it would no * longer be needed. However, in the typical (fast) roaming case * within an ESS this usually won't happen. */ The next flow lead to the warning eventually reported as a bug: 1. Disconnect from encrypted AP 2. Set crypto_tx_tailroom_pending_dec = 1 for the key 3. Schedule work 4. Reconnect to non-encrypted AP 5. Add a new key, setting the tailroom counter = 1 6. Got FW restart while pending counter is set ---> hit the warning While on it, the ieee80211_reset_crypto_tx_tailroom() func was merged into its single caller ieee80211_reenable_keys (previously called ieee80211_enable_keys). Also, we reset the crypto_tx_tailroom_pending_dec and remove the counters warning as we just reset both. Signed-off-by: Lior Cohen <lior2.cohen@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Link: https://lore.kernel.org/r/20190830112451.21655-7-luca@coelho.fi Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-30 11:24:49 +00:00
void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_key *key;
struct ieee80211_sub_if_data *vlan;
[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>
2007-08-28 21:01:55 +00:00
lockdep_assert_wiphy(sdata->local->hw.wiphy);
[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>
2007-08-28 21:01:55 +00:00
mutex_lock(&sdata->local->key_mtx);
sdata->crypto_tx_tailroom_needed_cnt = 0;
mac80211: clear crypto tx tailroom counter upon keys enable In case we got a fw restart while roaming from encrypted AP to non-encrypted one, we might end up with hitting a warning on the pending counter crypto_tx_tailroom_pending_dec having a non-zero value. The following comment taken from net/mac80211/key.c explains the rational for the delayed tailroom needed: /* * The reason for the delayed tailroom needed decrementing is to * make roaming faster: during roaming, all keys are first deleted * and then new keys are installed. The first new key causes the * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes * the cost of synchronize_net() (which can be slow). Avoid this * by deferring the crypto_tx_tailroom_needed_cnt decrementing on * key removal for a while, so if we roam the value is larger than * zero and no 0->1 transition happens. * * The cost is that if the AP switching was from an AP with keys * to one without, we still allocate tailroom while it would no * longer be needed. However, in the typical (fast) roaming case * within an ESS this usually won't happen. */ The next flow lead to the warning eventually reported as a bug: 1. Disconnect from encrypted AP 2. Set crypto_tx_tailroom_pending_dec = 1 for the key 3. Schedule work 4. Reconnect to non-encrypted AP 5. Add a new key, setting the tailroom counter = 1 6. Got FW restart while pending counter is set ---> hit the warning While on it, the ieee80211_reset_crypto_tx_tailroom() func was merged into its single caller ieee80211_reenable_keys (previously called ieee80211_enable_keys). Also, we reset the crypto_tx_tailroom_pending_dec and remove the counters warning as we just reset both. Signed-off-by: Lior Cohen <lior2.cohen@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Link: https://lore.kernel.org/r/20190830112451.21655-7-luca@coelho.fi Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-30 11:24:49 +00:00
sdata->crypto_tx_tailroom_pending_dec = 0;
if (sdata->vif.type == NL80211_IFTYPE_AP) {
mac80211: clear crypto tx tailroom counter upon keys enable In case we got a fw restart while roaming from encrypted AP to non-encrypted one, we might end up with hitting a warning on the pending counter crypto_tx_tailroom_pending_dec having a non-zero value. The following comment taken from net/mac80211/key.c explains the rational for the delayed tailroom needed: /* * The reason for the delayed tailroom needed decrementing is to * make roaming faster: during roaming, all keys are first deleted * and then new keys are installed. The first new key causes the * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes * the cost of synchronize_net() (which can be slow). Avoid this * by deferring the crypto_tx_tailroom_needed_cnt decrementing on * key removal for a while, so if we roam the value is larger than * zero and no 0->1 transition happens. * * The cost is that if the AP switching was from an AP with keys * to one without, we still allocate tailroom while it would no * longer be needed. However, in the typical (fast) roaming case * within an ESS this usually won't happen. */ The next flow lead to the warning eventually reported as a bug: 1. Disconnect from encrypted AP 2. Set crypto_tx_tailroom_pending_dec = 1 for the key 3. Schedule work 4. Reconnect to non-encrypted AP 5. Add a new key, setting the tailroom counter = 1 6. Got FW restart while pending counter is set ---> hit the warning While on it, the ieee80211_reset_crypto_tx_tailroom() func was merged into its single caller ieee80211_reenable_keys (previously called ieee80211_enable_keys). Also, we reset the crypto_tx_tailroom_pending_dec and remove the counters warning as we just reset both. Signed-off-by: Lior Cohen <lior2.cohen@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Link: https://lore.kernel.org/r/20190830112451.21655-7-luca@coelho.fi Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-30 11:24:49 +00:00
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
vlan->crypto_tx_tailroom_needed_cnt = 0;
mac80211: clear crypto tx tailroom counter upon keys enable In case we got a fw restart while roaming from encrypted AP to non-encrypted one, we might end up with hitting a warning on the pending counter crypto_tx_tailroom_pending_dec having a non-zero value. The following comment taken from net/mac80211/key.c explains the rational for the delayed tailroom needed: /* * The reason for the delayed tailroom needed decrementing is to * make roaming faster: during roaming, all keys are first deleted * and then new keys are installed. The first new key causes the * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes * the cost of synchronize_net() (which can be slow). Avoid this * by deferring the crypto_tx_tailroom_needed_cnt decrementing on * key removal for a while, so if we roam the value is larger than * zero and no 0->1 transition happens. * * The cost is that if the AP switching was from an AP with keys * to one without, we still allocate tailroom while it would no * longer be needed. However, in the typical (fast) roaming case * within an ESS this usually won't happen. */ The next flow lead to the warning eventually reported as a bug: 1. Disconnect from encrypted AP 2. Set crypto_tx_tailroom_pending_dec = 1 for the key 3. Schedule work 4. Reconnect to non-encrypted AP 5. Add a new key, setting the tailroom counter = 1 6. Got FW restart while pending counter is set ---> hit the warning While on it, the ieee80211_reset_crypto_tx_tailroom() func was merged into its single caller ieee80211_reenable_keys (previously called ieee80211_enable_keys). Also, we reset the crypto_tx_tailroom_pending_dec and remove the counters warning as we just reset both. Signed-off-by: Lior Cohen <lior2.cohen@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Link: https://lore.kernel.org/r/20190830112451.21655-7-luca@coelho.fi Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-08-30 11:24:49 +00:00
vlan->crypto_tx_tailroom_pending_dec = 0;
}
}
if (ieee80211_sdata_running(sdata)) {
list_for_each_entry(key, &sdata->key_list, list) {
increment_tailroom_need_count(sdata);
ieee80211_key_enable_hw_accel(key);
}
}
mutex_unlock(&sdata->local->key_mtx);
}
void ieee80211_iter_keys(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
void (*iter)(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct ieee80211_key_conf *key,
void *data),
void *iter_data)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_key *key, *tmp;
struct ieee80211_sub_if_data *sdata;
lockdep_assert_wiphy(hw->wiphy);
mutex_lock(&local->key_mtx);
if (vif) {
sdata = vif_to_sdata(vif);
list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
iter(hw, &sdata->vif,
key->sta ? &key->sta->sta : NULL,
&key->conf, iter_data);
} else {
list_for_each_entry(sdata, &local->interfaces, list)
list_for_each_entry_safe(key, tmp,
&sdata->key_list, list)
iter(hw, &sdata->vif,
key->sta ? &key->sta->sta : NULL,
&key->conf, iter_data);
}
mutex_unlock(&local->key_mtx);
}
EXPORT_SYMBOL(ieee80211_iter_keys);
static void
_ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
struct ieee80211_sub_if_data *sdata,
void (*iter)(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct ieee80211_key_conf *key,
void *data),
void *iter_data)
{
struct ieee80211_key *key;
list_for_each_entry_rcu(key, &sdata->key_list, list) {
/* skip keys of station in removal process */
if (key->sta && key->sta->removed)
continue;
if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
continue;
iter(hw, &sdata->vif,
key->sta ? &key->sta->sta : NULL,
&key->conf, iter_data);
}
}
void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
void (*iter)(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct ieee80211_key_conf *key,
void *data),
void *iter_data)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
if (vif) {
sdata = vif_to_sdata(vif);
_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
} else {
list_for_each_entry_rcu(sdata, &local->interfaces, list)
_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
}
}
EXPORT_SYMBOL(ieee80211_iter_keys_rcu);
static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
struct list_head *keys)
{
struct ieee80211_key *key, *tmp;
decrease_tailroom_need_count(sdata,
sdata->crypto_tx_tailroom_pending_dec);
sdata->crypto_tx_tailroom_pending_dec = 0;
ieee80211_debugfs_key_remove_mgmt_default(sdata);
ieee80211_debugfs_key_remove_beacon_default(sdata);
list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
ieee80211_key_replace(key->sdata, NULL, key->sta,
key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
key, NULL);
list_add_tail(&key->list, keys);
}
ieee80211_debugfs_key_update_default(sdata);
}
void ieee80211_remove_link_keys(struct ieee80211_link_data *link,
struct list_head *keys)
{
struct ieee80211_sub_if_data *sdata = link->sdata;
struct ieee80211_local *local = sdata->local;
struct ieee80211_key *key, *tmp;
mutex_lock(&local->key_mtx);
list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
if (key->conf.link_id != link->link_id)
continue;
ieee80211_key_replace(key->sdata, link, key->sta,
key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
key, NULL);
list_add_tail(&key->list, keys);
}
mutex_unlock(&local->key_mtx);
}
void ieee80211_free_key_list(struct ieee80211_local *local,
struct list_head *keys)
{
struct ieee80211_key *key, *tmp;
mutex_lock(&local->key_mtx);
list_for_each_entry_safe(key, tmp, keys, list)
__ieee80211_key_destroy(key, false);
mutex_unlock(&local->key_mtx);
}
void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
bool force_synchronize)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_sub_if_data *vlan;
struct ieee80211_sub_if_data *master;
struct ieee80211_key *key, *tmp;
LIST_HEAD(keys);
wiphy_delayed_work_cancel(local->hw.wiphy,
&sdata->dec_tailroom_needed_wk);
mutex_lock(&local->key_mtx);
ieee80211_free_keys_iface(sdata, &keys);
if (sdata->vif.type == NL80211_IFTYPE_AP) {
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
ieee80211_free_keys_iface(vlan, &keys);
}
if (!list_empty(&keys) || force_synchronize)
synchronize_net();
list_for_each_entry_safe(key, tmp, &keys, list)
__ieee80211_key_destroy(key, false);
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
if (sdata->bss) {
master = container_of(sdata->bss,
struct ieee80211_sub_if_data,
u.ap);
WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
master->crypto_tx_tailroom_needed_cnt);
}
} else {
WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
sdata->crypto_tx_tailroom_pending_dec);
}
if (sdata->vif.type == NL80211_IFTYPE_AP) {
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
vlan->crypto_tx_tailroom_pending_dec);
}
mutex_unlock(&local->key_mtx);
[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>
2007-08-28 21:01:55 +00:00
}
void ieee80211_free_sta_keys(struct ieee80211_local *local,
struct sta_info *sta)
{
struct ieee80211_key *key;
int i;
mutex_lock(&local->key_mtx);
mac80211: prepare sta handling for MLO support Currently in mac80211 each STA object is represented using sta_info datastructure with the associated STA specific information and drivers access ieee80211_sta part of it. With MLO (Multi Link Operation) support being added in 802.11be standard, though the association is logically with a single Multi Link capable STA, at the physical level communication can happen via different advertised links (uniquely identified by Channel, operating class, BSSID) and hence the need to handle multiple link STA parameters within a composite sta_info object called the MLD STA. The different link STA part of MLD STA are identified using the link address which can be same or different as the MLD STA address and unique link id based on the link vif. To support extension of such a model, the sta_info datastructure is modified to hold multiple link STA objects with link specific params currently within sta_info moved to this new structure. Similarly this is done for ieee80211_sta as well which will be accessed within mac80211 as well as by drivers, hence trivial driver changes are expected to support this. For current non MLO supported drivers, only one link STA is present and link information is accessed via 'deflink' member. For MLO drivers, we still need to define the APIs etc. to get the correct link ID and access the correct part of the station info. Currently in mac80211, all link STA info are accessed directly via deflink. These will be updated to access via link pointers indexed by link id with MLO support patches, with link id being 0 for non MLO supported cases. Except for couple of macro related changes, below spatch takes care of updating mac80211 and driver code to access to the link STA info via deflink. @ieee80211_sta@ struct ieee80211_sta *s; struct sta_info *si; identifier var = {supp_rates, ht_cap, vht_cap, he_cap, he_6ghz_capa, eht_cap, rx_nss, bandwidth, txpwr}; @@ ( s-> - var + deflink.var | si->sta. - var + deflink.var ) @sta_info@ struct sta_info *si; identifier var = {gtk, pcpu_rx_stats, rx_stats, rx_stats_avg, status_stats, tx_stats, cur_max_bandwidth}; @@ ( si-> - var + deflink.var ) Signed-off-by: Sriram R <quic_srirrama@quicinc.com> Link: https://lore.kernel.org/r/1649086883-13246-1-git-send-email-quic_srirrama@quicinc.com [remove MLO-drivers notes from commit message, not clear yet; run spatch] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2022-04-04 15:41:23 +00:00
for (i = 0; i < ARRAY_SIZE(sta->deflink.gtk); i++) {
key = key_mtx_dereference(local, sta->deflink.gtk[i]);
if (!key)
continue;
ieee80211_key_replace(key->sdata, NULL, key->sta,
key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
key, NULL);
mac80211: restrict delayed tailroom needed decrement 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>
2018-07-10 11:18:27 +00:00
__ieee80211_key_destroy(key, key->sdata->vif.type ==
NL80211_IFTYPE_STATION);
}
for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
key = key_mtx_dereference(local, sta->ptk[i]);
if (!key)
continue;
ieee80211_key_replace(key->sdata, NULL, key->sta,
key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
key, NULL);
mac80211: restrict delayed tailroom needed decrement 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>
2018-07-10 11:18:27 +00:00
__ieee80211_key_destroy(key, key->sdata->vif.type ==
NL80211_IFTYPE_STATION);
}
mutex_unlock(&local->key_mtx);
}
void ieee80211_delayed_tailroom_dec(struct wiphy *wiphy,
struct wiphy_work *wk)
{
struct ieee80211_sub_if_data *sdata;
sdata = container_of(wk, struct ieee80211_sub_if_data,
dec_tailroom_needed_wk.work);
/*
* The reason for the delayed tailroom needed decrementing is to
* make roaming faster: during roaming, all keys are first deleted
* and then new keys are installed. The first new key causes the
* crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
* the cost of synchronize_net() (which can be slow). Avoid this
* by deferring the crypto_tx_tailroom_needed_cnt decrementing on
* key removal for a while, so if we roam the value is larger than
* zero and no 0->1 transition happens.
*
* The cost is that if the AP switching was from an AP with keys
* to one without, we still allocate tailroom while it would no
* longer be needed. However, in the typical (fast) roaming case
* within an ESS this usually won't happen.
*/
mutex_lock(&sdata->local->key_mtx);
decrease_tailroom_need_count(sdata,
sdata->crypto_tx_tailroom_pending_dec);
sdata->crypto_tx_tailroom_pending_dec = 0;
mutex_unlock(&sdata->local->key_mtx);
}
void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
const u8 *replay_ctr, gfp_t gfp)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
}
EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
int tid, struct ieee80211_key_seq *seq)
{
struct ieee80211_key *key;
const u8 *pn;
key = container_of(keyconf, struct ieee80211_key, conf);
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_TKIP:
if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
return;
seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
break;
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
return;
if (tid < 0)
pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
else
pn = key->u.ccmp.rx_pn[tid];
memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
if (WARN_ON(tid != 0))
return;
pn = key->u.aes_cmac.rx_pn;
memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
if (WARN_ON(tid != 0))
return;
pn = key->u.aes_gmac.rx_pn;
memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
return;
if (tid < 0)
pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
else
pn = key->u.gcmp.rx_pn[tid];
memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
break;
}
}
EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
int tid, struct ieee80211_key_seq *seq)
{
struct ieee80211_key *key;
u8 *pn;
key = container_of(keyconf, struct ieee80211_key, conf);
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_TKIP:
if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
return;
key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
break;
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
return;
if (tid < 0)
pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
else
pn = key->u.ccmp.rx_pn[tid];
memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
if (WARN_ON(tid != 0))
return;
pn = key->u.aes_cmac.rx_pn;
memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
if (WARN_ON(tid != 0))
return;
pn = key->u.aes_gmac.rx_pn;
memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
return;
if (tid < 0)
pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
else
pn = key->u.gcmp.rx_pn[tid];
memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
break;
default:
WARN_ON(1);
break;
}
}
EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
{
struct ieee80211_key *key;
key = container_of(keyconf, struct ieee80211_key, conf);
assert_key_lock(key->local);
/*
* if key was uploaded, we assume the driver will/has remove(d)
* it, so adjust bookkeeping accordingly
*/
if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
increment_tailroom_need_count(key->sdata);
}
ieee80211_key_free(key, false);
}
EXPORT_SYMBOL_GPL(ieee80211_remove_key);
struct ieee80211_key_conf *
ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
struct ieee80211_key_conf *keyconf)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct ieee80211_key *key;
int err;
if (WARN_ON(!local->wowlan))
return ERR_PTR(-EINVAL);
if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
return ERR_PTR(-EINVAL);
key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
keyconf->keylen, keyconf->key,
0, NULL);
if (IS_ERR(key))
return ERR_CAST(key);
if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
/* FIXME: this function needs to get a link ID */
err = ieee80211_key_link(key, &sdata->deflink, NULL);
if (err)
return ERR_PTR(err);
return &key->conf;
}
EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
void ieee80211_key_mic_failure(struct ieee80211_key_conf *keyconf)
{
struct ieee80211_key *key;
key = container_of(keyconf, struct ieee80211_key, conf);
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
key->u.aes_cmac.icverrors++;
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
key->u.aes_gmac.icverrors++;
break;
default:
/* ignore the others for now, we don't keep counters now */
break;
}
}
EXPORT_SYMBOL_GPL(ieee80211_key_mic_failure);
void ieee80211_key_replay(struct ieee80211_key_conf *keyconf)
{
struct ieee80211_key *key;
key = container_of(keyconf, struct ieee80211_key, conf);
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
key->u.ccmp.replays++;
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
key->u.aes_cmac.replays++;
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
key->u.aes_gmac.replays++;
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
key->u.gcmp.replays++;
break;
}
}
EXPORT_SYMBOL_GPL(ieee80211_key_replay);
int ieee80211_key_switch_links(struct ieee80211_sub_if_data *sdata,
unsigned long del_links_mask,
unsigned long add_links_mask)
{
struct ieee80211_key *key;
int ret;
list_for_each_entry(key, &sdata->key_list, list) {
if (key->conf.link_id < 0 ||
!(del_links_mask & BIT(key->conf.link_id)))
continue;
/* shouldn't happen for per-link keys */
WARN_ON(key->sta);
ieee80211_key_disable_hw_accel(key);
}
list_for_each_entry(key, &sdata->key_list, list) {
if (key->conf.link_id < 0 ||
!(add_links_mask & BIT(key->conf.link_id)))
continue;
/* shouldn't happen for per-link keys */
WARN_ON(key->sta);
ret = ieee80211_key_enable_hw_accel(key);
if (ret)
return ret;
}
return 0;
}