Hi, > > > If so, can we do something like what ieee80211_process_sa_query_req in > > > net/mac80211/rx.c or ieee80211_tdls_prep_mgmt_packet in > > > net/mac80211/tdls.c do? E.g. use ieee80211_tx_skb or > > > __ieee80211_subif_start_xmit or similar to inject the skb with the > > > DONT_ENCRYPT flag? > > > > Yes, this will work - but like I said, it requires more control over > > the SKB than cfg80211 has today, and than you can get through the > > regular netdev xmit. > > So, I'm a bit lost here. You're saying this will work but then it > won't. Are you saying this would only work for mac80211 based devices > (e.g. ones that implement ieee80211_ops) but not ones that implement > cfg80211_ops? I presume because those provide their own net_device_ops? Heh, yeah, badly phrased. It'll work to do it like process_sa_query or similar code, for mac80211 drivers. What will *not* work is actually building and submitting the SKB in cfg80211 though, since you can't even set the DONT_ENCRYPT flag from there. > > > This would likely mean that legacy behavior would still have to be > > > supported for quite some time (forever?) for drivers that don't get > > > around to implementing this, which would be unfortunate. > > > > What do you mean by "legacy behaviour"? *Drivers* don't really need to > > do anything one way or the other, and mac80211 is the only thing > > implementing control port encrypt/ethertype right now, I suspect. > > > > When I say legacy I mean 'over netdev', e.g. not over nl80211. We need to support that behaviour forever anyway, for existing versions of userspace software. > Okay, so what you're saying is that the current CONTROL_PORT_* stuff > doesn't work on anything besides mac80211 since drivers can completely > ignore stuff inside cfg80211_connect_params. And there's no way for > userspace to know this ahead of time? Yes, NL80211_ATTR_CONTROL_PORT_ETHERTYPE is an attribute set in the wiphy info - see WIPHY_FLAG_CONTROL_PORT_PROTOCOL in the code. > So essentially we'd need a new operation in cfg80211_ops that would > accept the control port frame data and some control flags. Do we want > to pass in an skb with all the 802.11 headers set or a 802.3 formatted > skb (since that is what other data frames look like initially on the > netdev). I think 802.3 format would be better - matches better for full-MAC devices that might do all header conversion in the device, and getting the BSSID might even be difficult from cfg80211, etc. johannes
