nl80211: Add Michael MIC failure event

Define a new nl80211 event, NL80211_CMD_MICHAEL_MIC_FAILURE, to be
used to notify user space about locally detected Michael MIC failures.
This matches with the MLME-MICHAELMICFAILURE.indication() primitive.

Since we do not actually have TSC in the skb anymore when
mac80211_ev_michael_mic_failure() is called, that function is changed
to take in the TSC as an optional parameter instead of as a
requirement to include the TSC after the hdr field (which we did not
really follow). For now, TSC is not included in the events from
mac80211, but it could be added at some point.

Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 195424eee77d..1394115cde95 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3430,6 +3430,46 @@ void nl80211_send_disassoc(struct cfg80211_registered_device *rdev,
                                 NL80211_CMD_DISASSOCIATE);
 }
 
+void nl80211_michael_mic_failure(struct cfg80211_registered_device *rdev,
+                                 struct net_device *netdev, const u8 *addr,
+                                 enum nl80211_key_type key_type, int key_id,
+                                 const u8 *tsc)
+{
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_MICHAEL_MIC_FAILURE);
+        if (!hdr) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx);
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex);
+        if (addr)
+                NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, addr);
+        NLA_PUT_U32(msg, NL80211_ATTR_KEY_TYPE, key_type);
+        NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, key_id);
+        if (tsc)
+                NLA_PUT(msg, NL80211_ATTR_KEY_SEQ, 6, tsc);
+
+        if (genlmsg_end(msg, hdr) < 0) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        genlmsg_multicast(msg, 0, nl80211_mlme_mcgrp.id, GFP_KERNEL);
+        return;
+
+ nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+        nlmsg_free(msg);
+}
+
 /* initialisation/exit functions */
 
 int nl80211_init(void)