No description
17d4b77472
PMKID derivation with the Suite B AKMs is a special case compared to other AKMs since that derivation uses KCK instead of PMK as an input. This means that the PMKSA cache entry can be added only after KCK has been derived during 4-way handshake. This also means that PMKID would change every time 4-way handshake is repeated even when maintaining the same PMK (i.e., during PTK rekeying and new associations even if they use PMKSA caching). wpa_supplicant was previously replacing the PMKSA cache entry whenever a new PMKID was derived. This did not match hostapd expectations on the AP side since hostapd did not update the PMKSA cache entry after it was created. Consequently, PMKSA caching could be used only once (assuming no PTK rekeying happened before that). Fix this by making wpa_supplicant behave consistently with hostapd, i.e., by adding the Suite B PMKSA cache entries with the PMKID from the very first 4-way handshake following PMK derivation and then not updating the PMKID. IEEE Std 802.11-2016 is somewhat vague in this area and it seems to allow both cases to be used (initial PMKID or any consecutive PMKID derived from the same PMK). While both cases could be supported that would result in significantly more complex implementation and need to store multiple PMKID values. It looks better to clarify the standard to explicitly note that only the first PMKID derived after PMK derivation is used (i.e., match the existing hostapd implementation). Signed-off-by: Jouni Malinen <jouni@codeaurora.org> |
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| doc | ||
| eap_example | ||
| hostapd | ||
| hs20 | ||
| mac80211_hwsim/tools | ||
| radius_example | ||
| src | ||
| tests | ||
| wlantest | ||
| wpa_supplicant | ||
| wpadebug | ||
| wpaspy | ||
| .gitignore | ||
| Android.mk | ||
| build_release | ||
| CONTRIBUTIONS | ||
| COPYING | ||
| README | ||
wpa_supplicant and hostapd -------------------------- Copyright (c) 2002-2017, Jouni Malinen <j@w1.fi> and contributors All Rights Reserved. These programs are licensed under the BSD license (the one with advertisement clause removed). If you are submitting changes to the project, please see CONTRIBUTIONS file for more instructions. This package may include either wpa_supplicant, hostapd, or both. See README file respective subdirectories (wpa_supplicant/README or hostapd/README) for more details. Source code files were moved around in v0.6.x releases and compared to earlier releases, the programs are now built by first going to a subdirectory (wpa_supplicant or hostapd) and creating build configuration (.config) and running 'make' there (for Linux/BSD/cygwin builds). License ------- This software may be distributed, used, and modified under the terms of BSD license: Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name(s) of the above-listed copyright holder(s) nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.