Up to now, key manipulation is supposed to run under RTNL to
avoid concurrent manipulations and also allow the set_key()
hardware callback to sleep. This is not feasible because STA
structs are rcu-protected and thus a lot of operations there
cannot take the RTNL. Also, key references are rcu-protected
so we cannot do things atomically.
This patch changes key locking completely:
* key operations are now atomic
* hardware crypto offload is enabled and disabled from
a workqueue, due to that key freeing is also delayed
* debugfs code is also run from a workqueue
* keys reference STAs (and vice versa!) so during STA
unlink the STAs key reference is removed but not the
keys STA reference, to avoid races key todo work is
run before STA destruction.
* fewer STA operations now need the RTNL which was
required due to key operations
This fixes the locking problems lockdep pointed out and also
makes things more light-weight because the rtnl isn't required
as much.
Note that the key todo lock/key mutex are global locks, this
is not required, of course, they could be per-hardware instead.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add a new file 'ifindex' to each key's debugfs dir to
allow finding which interface the key was configured on.
This isn't done as a symlink because of possible netdev
name changes.
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>
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>
This patch embeds the struct ieee80211_key_conf into struct ieee80211_key
and thus avoids allocations and having data present twice.
This required some more changes:
1) The removal of the IEEE80211_KEY_DEFAULT_TX_KEY key flag.
This flag isn't used by drivers nor should it be since
we have a set_key_idx() callback. Maybe that callback needs
to be extended to include the key conf, but only a driver that
requires it will tell.
2) The removal of the IEEE80211_KEY_DEFAULT_WEP_ONLY key flag.
This flag is global, so it shouldn't be passed in the key
conf structure. Pass it to the function instead.
Also, this patch removes the AID parameter to the set_key() callback
because it is currently unused and the hardware currently cannot know
about the AID anyway. I suspect this was used with some hardware that
actually selected the AID itself, but that functionality was removed.
Additionally, I've removed the ALG_NULL key algorithm since we have
ALG_NONE.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes two issues with the key debugfs:
1) key index obviously isn't unique
2) various missing break statements led to bogus output
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>
Export various mac80211 internal variables through debugfs.
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg
Joe Perches
Jiri Benc