cfg80211/nl80211: Add PMKSA caching candidate event

When the driver (or most likely firmware) decides which AP to use
for roaming based on internal scan result processing, user space
needs to be notified of PMKSA caching candidates to allow RSN
pre-authentication to be used.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index f173075..460b12a 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -499,6 +499,9 @@
  *	this command may also be sent by the driver as an MLME event to
  *	inform userspace of the new replay counter.
  *
+ * @NL80211_CMD_PMKSA_CANDIDATE: This is used as an event to inform userspace
+ *	of PMKSA caching dandidates.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -623,6 +626,8 @@
 
 	NL80211_CMD_SET_REKEY_OFFLOAD,
 
+	NL80211_CMD_PMKSA_CANDIDATE,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -1070,6 +1075,9 @@
  * @NL80211_ATTR_ROAM_SUPPORT: Indicates whether the firmware is capable of
  *	roaming to another AP in the same ESS if the signal lever is low.
  *
+ * @NL80211_ATTR_PMKSA_CANDIDATE: Nested attribute containing the PMKSA caching
+ *	candidate information, see &enum nl80211_pmksa_candidate_attr.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -1288,6 +1296,8 @@
 	NL80211_ATTR_SCHED_SCAN_MATCH,
 	NL80211_ATTR_MAX_MATCH_SETS,
 
+	NL80211_ATTR_PMKSA_CANDIDATE,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -2558,4 +2568,27 @@
 	NL80211_STA_WME_MAX = __NL80211_STA_WME_AFTER_LAST - 1
 };
 
+/**
+ * enum nl80211_pmksa_candidate_attr - attributes for PMKSA caching candidates
+ * @__NL80211_PMKSA_CANDIDATE_INVALID: invalid number for nested attributes
+ * @NL80211_PMKSA_CANDIDATE_INDEX: candidate index (u32; the smaller, the higher
+ *	priority)
+ * @NL80211_PMKSA_CANDIDATE_BSSID: candidate BSSID (6 octets)
+ * @NL80211_PMKSA_CANDIDATE_PREAUTH: RSN pre-authentication supported (flag)
+ * @NUM_NL80211_PMKSA_CANDIDATE: number of PMKSA caching candidate attributes
+ *	(internal)
+ * @MAX_NL80211_PMKSA_CANDIDATE: highest PMKSA caching candidate attribute
+ *	(internal)
+ */
+enum nl80211_pmksa_candidate_attr {
+	__NL80211_PMKSA_CANDIDATE_INVALID,
+	NL80211_PMKSA_CANDIDATE_INDEX,
+	NL80211_PMKSA_CANDIDATE_BSSID,
+	NL80211_PMKSA_CANDIDATE_PREAUTH,
+
+	/* keep last */
+	NUM_NL80211_PMKSA_CANDIDATE,
+	MAX_NL80211_PMKSA_CANDIDATE = NUM_NL80211_PMKSA_CANDIDATE - 1
+};
+
 #endif /* __LINUX_NL80211_H */