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>

3 files changed, 55 insertions, 0 deletions

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 33ff7cca496b..1407244a647e 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -43,3 +43,13 @@ void cfg80211_send_disassoc(struct net_device *dev, const u8 *buf, size_t len)
         nl80211_send_disassoc(rdev, dev, buf, len);
 }
 EXPORT_SYMBOL(cfg80211_send_disassoc);
+
+void cfg80211_michael_mic_failure(struct net_device *dev, const u8 *addr,
+                                  enum nl80211_key_type key_type, int key_id,
+                                  const u8 *tsc)
+{
+        struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
+        nl80211_michael_mic_failure(rdev, dev, addr, key_type, key_id, tsc);
+}
+EXPORT_SYMBOL(cfg80211_michael_mic_failure);
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)
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 55686fc264f0..e4b92cccd157 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -23,5 +23,10 @@ extern void nl80211_send_deauth(struct cfg80211_registered_device *rdev,
 extern void nl80211_send_disassoc(struct cfg80211_registered_device *rdev,
                                   struct net_device *netdev,
                                   const u8 *buf, size_t len);
+extern 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);
 
 #endif /* __NET_WIRELESS_NL80211_H */