cfg80211/mac80211: Add 802.11d support

This adds country IE parsing to mac80211 and enables its usage
within the new regulatory infrastructure in cfg80211. We parse
the country IEs only on management beacons for the BSSID you are
associated to and disregard the IEs when the country and environment
(indoor, outdoor, any) matches the already processed country IE.

To avoid following misinformed or outdated APs we build and use
a regulatory domain out of the intersection between what the AP
provides us on the country IE and what CRDA is aware is allowed
on the same country.

A secondary device is allowed to follow only the same country IE
as it make no sense for two devices on a system to be in two
different countries.

In the case the AP is using country IEs for an incorrect country
the user may help compliance further by setting the regulatory
domain before or after the IE is parsed and in that case another
intersection will be performed.

CONFIG_WIRELESS_OLD_REGULATORY is supported but requires CRDA
present.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index d81a4d2cd3aa..30adaddeed27 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1736,6 +1736,13 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 					       ap_ht_cap_flags);
 	}
 
+	if (elems.country_elem) {
+		/* Note we are only reviewing this on beacons
+		 * for the BSSID we are associated to */
+		regulatory_hint_11d(local->hw.wiphy,
+			elems.country_elem, elems.country_elem_len);
+	}
+
 	ieee80211_bss_info_change_notify(sdata, changed);
 }