Previously, both NULL and ff:ff:ff:ff:ff:ff addr were used in various
places to indicate default/broadcast keys. Make this more consistent
and useful by defining NULL to mean default key (i.e., used both for
unicast and broadcast) and ff:ff:ff:ff:ff:ff to indicate broadcast
key (i.e., used only with broadcast).
This commit adds a new wrapper, random_get_bytes(), that is currently
defined to use os_get_random() as is. The places using
random_get_bytes() depend on the returned value being strong random
number, i.e., something that is infeasible for external device to
figure out. These values are used either directly as a key or as
nonces/challenges that are used as input for key derivation or
authentication.
The remaining direct uses of os_get_random() do not need as strong
random numbers to function correctly.
Commit 83935317a7 added forced
disconnection in case of 4-way handshake failures. However, it should
not have changed the case where the supplicant is requesting fallback
to full EAP authentication if the PMKID in EAPOL-Key message 1/4 is
not know. This case needs to send an EAPOL-Start frame instead of
EAPOL-Key message 2/4.
This works around a problem with APs that try to force PMKSA caching
even when the client does not include PMKID in (re)association request
frame to request it. [Bug 355]
This sets the FT Capability and Policy field in the MDIE to the values
received from the target AP (if available). This fixes the MDIE contents
during FT Protocol, but the correct value may not yet be used in initial
mobility domain association.
IEEE Std 802.11r-2008, 11A.4.2 describes FT initial mobility domain
association in an RSN to include PMKR1Name in the PMKID-List field
in RSN IE in messages 2/4 and 3/4. This makes the RSN IE not be
bitwise identical with the values used in Beacon, Probe Response,
(Re)association Request frames.
The previous versions of wpa_supplicant and hostapd did not add the
PMKR1Name value in EAPOL-Key frame and did not accept it if added
(due to bitwise comparison of RSN IEs). This commit fixes the
implementation to be compliant with the standard by adding the
PMKR1Name value into EAPOL-Key messages during FT 4-Way Handshake and
by verifying that the received value matches with the value derived
locally.
This breaks interoperability with previous wpa_supplicant/hostapd
versions.
In addition, start ordering header file includes to be in more
consistent order: system header files, src/utils, src/*, same
directory as the *.c file.
This makes it clearer which files are including header from src/common.
Some of these cases should probably be cleaned up in the future not to
do that.
In addition, src/common/nl80211_copy.h and wireless_copy.h were moved
into src/drivers since they are only used by driver wrappers and do not
need to live in src/common.
There is no point in trying to continue if a 4-way handshake frame is
discarded or if PTK/GTK/IGTK configuration fails. Force the client to
disconnect in such a case to avoid confusing user by claiming the
connection was successfully completed.
IEEE 802.11r KDF uses key length in the derivation and as such, the PTK
length must be specified correctly. The previous version was deriving
using 512-bit PTK regardless of the negotiated cipher suite; this works
for TKIP, but not for CCMP. Update the code to use proper PTK length
based on the pairwise cipher.
This fixed PTK derivation for both IEEE 802.11r and IEEE 802.11w (when
using AKMP that specifies SHA-256-based key derivation). The fixed
version does not interoperate with the previous versions. [Bug 307]
Previously, both CONFIG_IEEE80211W=y and CONFIG_IEEE80211R=y were needed
to enable SHA256-based key handshake (WPA-PSK-SHA256 and
WPA-EAP-SHA256). This can now be done with just CONFIG_IEEE80211W=y.
It looks like some Windows NDIS drivers (e.g., Intel) do not clear the
PMKID list even when wpa_supplicant explicitly sets the list to be
empty. In such a case, the driver ends up trying to use PMKSA caching
with the AP and wpa_supplicant may not have the PMK that would be needed
to complete 4-way handshake.
RSN processing already had some code for aborting PMKSA caching by
sending EAPOL-Start. However, this was not triggered in this particular
case where the driver generates the RSN IE. With this change, this case
is included, too, and the failed PMKSA caching attempt is cleanly
canceled and wpa_supplicant can fall back to full EAP authentication.
Added a new configuration option, wpa_ptk_rekey, that can be used to
enforce frequent PTK rekeying, e.g., to mitigate some attacks against TKIP
deficiencies. This can be set either by the Authenticator (to initiate
periodic 4-way handshake to rekey PTK) or by the Supplicant (to request
Authenticator to rekey PTK).
With both wpa_ptk_rekey and wpa_group_rekey (in hostapd) set to 600, TKIP
keys will not be used for more than 10 minutes which may make some attacks
against TKIP more difficult to implement.
IEEE 802.11w/D6.0 defines new AKMPs to indicate SHA256-based algorithms for
key derivation (and AES-CMAC for EAPOL-Key MIC). Add support for using new
AKMPs and clean up AKMP processing with helper functions in defs.h.
wpa_sm_set_config() can be called even if the network block does not
change. However, the previous version ended up calling
pmksa_cache_notify_reconfig() every time and this cleared the network
context from PMKSA cache entries. This prevented OKC from ever being used.
Do not call pmksa_cache_notify_reconfig() if the network context remains
unchanged to allow OKC to be used.
Function 'wpa_sm_set_config' used the argument 'config' as the network
context which is a pointer to a local variable of the function
'wpa_supplicant_rsn_supp_set_config'.
This is one reason why no proactive key was generated. This network
context never matched with the network context saved in the pmksa cache
entries.
The structure 'rsn_supp_config' has already a member 'network_ctx' which
is now filled in by this patch with 'ssid'.
Signed-off-by: Michael Bernhard <michael.bernhard@bfh.ch>
This avoids getting stuck in state where wpa_supplicant has canceled scans,
but the driver is actually in disassociated state. The previously used code
that controlled scan timeout from WPA module is not really needed anymore
(and has not been needed for past four years since authentication timeout
was separated from scan request timeout), so this can simply be removed to
resolved the race condition. As an extra bonus, this simplifies the
interface to WPA module.
[Bug 261]
Transition. This fixes a potential issue where an incorrectly behaving AP
could send a group key update using the old (now invalid after reassociate)
PTK. This could also happen if there is a race condition between reporting
received EAPOL frames and association events.
