mac80211: support MIC error/replay detected counters driver update

Support the driver incrementing MIC error and replay detected
counters when having detected a bad frame, if it drops it directly
instead of relying on mac80211 to do the checks.

These are then exposed to userspace, though currently only in some
cases and in debugfs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20201129172929.fb59be9c6de8.Ife2260887366f585afadd78c983ebea93d2bb54b@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -5321,6 +5321,26 @@ ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 				const u8 *replay_ctr, gfp_t gfp);
 
+/**
+ * ieee80211_key_mic_failure - increment MIC failure counter for the key
+ *
+ * Note: this is really only safe if no other RX function is called
+ * at the same time.
+ *
+ * @keyconf: the key in question
+ */
+void ieee80211_key_mic_failure(struct ieee80211_key_conf *keyconf);
+
+/**
+ * ieee80211_key_replay - increment replay counter for the key
+ *
+ * Note: this is really only safe if no other RX function is called
+ * at the same time.
+ *
+ * @keyconf: the key in question
+ */
+void ieee80211_key_replay(struct ieee80211_key_conf *keyconf);
+
 /**
  * ieee80211_wake_queue - wake specific queue
  * @hw: pointer as obtained from ieee80211_alloc_hw().

net/mac80211/key.c

@@ -1300,3 +1300,52 @@ ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
 	return &key->conf;
 }
 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);
+
+void ieee80211_key_mic_failure(struct ieee80211_key_conf *keyconf)
+{
+	struct ieee80211_key *key;
+
+	key = container_of(keyconf, struct ieee80211_key, conf);
+
+	switch (key->conf.cipher) {
+	case WLAN_CIPHER_SUITE_AES_CMAC:
+	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
+		key->u.aes_cmac.icverrors++;
+		break;
+	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
+	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
+		key->u.aes_gmac.icverrors++;
+		break;
+	default:
+		/* ignore the others for now, we don't keep counters now */
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(ieee80211_key_mic_failure);
+
+void ieee80211_key_replay(struct ieee80211_key_conf *keyconf)
+{
+	struct ieee80211_key *key;
+
+	key = container_of(keyconf, struct ieee80211_key, conf);
+
+	switch (key->conf.cipher) {
+	case WLAN_CIPHER_SUITE_CCMP:
+	case WLAN_CIPHER_SUITE_CCMP_256:
+		key->u.ccmp.replays++;
+		break;
+	case WLAN_CIPHER_SUITE_AES_CMAC:
+	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
+		key->u.aes_cmac.replays++;
+		break;
+	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
+	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
+		key->u.aes_gmac.replays++;
+		break;
+	case WLAN_CIPHER_SUITE_GCMP:
+	case WLAN_CIPHER_SUITE_GCMP_256:
+		key->u.gcmp.replays++;
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(ieee80211_key_replay);