On Tue, 2018-08-14 at 13:11 +0200, Johannes Berg wrote: > On Tue, 2018-08-07 at 00:48 +0200, Mathy Vanhoef wrote: > > When operating in station mode, ignore SA Query Request frames that > > contain extra payload data. The kernel doesn't know how to handle these > > frames. Instead, give userspace a chance to handle these frames. > > > > For example, with Operating Channel Validation, SA Query Requests may > > now contain an extra Operating Channel Information (OCI) element as > > payload data. The kernel should ignore these frames, since it does not > > know how to properly handle them. Instead, let userspace process these > > frames. > > > > Signed-off-by: Mathy Vanhoef <[email protected]> > > --- > > For background on Operating Channel Validation, see: > > https://mentor.ieee.org/802.11/dcn/17/11-17-1807-12-000m-defense-against-multi-channel-mitm-attacks-via-operating-channel-validation.docx > > > > A corresponding patchset was also recently submitted to Hostap, see "Add > > support for Operating Channel Validation (OCV)". > > In a perfect world, this seems fine. However, what if wpa_s doesn't > implement this (yet)? In that case, wouldn't it be better (or really > required) to still respond to the SA query request in the kernel? > > Since you change wpa_s to subscribe to the relevant action frame: > > > + /* SA Query Request */ > > + if (nl80211_register_action_frame(bss, (u8 *) "\x08\x00", 2) < 0) > > + ret = -1; > > we could change the logic to be > > if (!frame_includes_OCV || !cfg80211_rx_mgmt(...)) > respond_in_kernel(); >
An easier alternative might be to push ieee80211_process_sa_query_req() to after ieee80211_rx_h_userspace_mgmt() so it won't see the frames if userspace claimed them, but I'm not sure how that works in AP mode where hostapd claims all frames - though I guess these aren't relevant in AP mode? johannes
