[v3] cfg80211: Enhance the AKM advertizement to support per interface.

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index fa027d0d031b..83e92d5c20d8 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4398,6 +4398,21 @@  struct cfg80211_pmsr_capabilities {
 	} ftm;
 };
 
+/**
+ * struct wiphy_iftype_akm_suites - This structure encapsulates supported akm
+ * suites for interface types defined in @iftypes_mask. Each type in the
+ * @iftypes_mask must be unique across all instances of iftype_akm_suites.
+ *
+ * @iftypes_mask: bitmask of interfaces types
+ * @akm_suites: points to an array of supported akm suites
+ * @n_akm_suites: number of supported AKM suites
+ */
+struct wiphy_iftype_akm_suites {
+	u16 iftypes_mask;
+	const u32 *akm_suites;
+	int n_akm_suites;
+};
+
 /**
  * struct wiphy - wireless hardware description
  * @reg_notifier: the driver's regulatory notification callback,
@@ -4410,8 +4425,16 @@  struct cfg80211_pmsr_capabilities {
  * @signal_type: signal type reported in &struct cfg80211_bss.
  * @cipher_suites: supported cipher suites
  * @n_cipher_suites: number of supported cipher suites
- * @akm_suites: supported AKM suites
+ * @akm_suites: supported AKM suites. These are the default AKMs supported if
+ *	the supported AKMs not advertized for a specific interface type in
+ *	iftype_akm_suites.
  * @n_akm_suites: number of supported AKM suites
+ * @iftype_akm_suites: array of supported akm suites info per interface type.
+ *	Note that the bits in @iftypes_mask inside this structure cannot
+ *	overlap (i.e. only one occurrence of each type is allowed across all
+ *	instances of iftype_akm_suites).
+ * @num_iftype_akm_suites: number of interface types for which supported akm
+ *	suites are specified separately.
  * @retry_short: Retry limit for short frames (dot11ShortRetryLimit)
  * @retry_long: Retry limit for long frames (dot11LongRetryLimit)
  * @frag_threshold: Fragmentation threshold (dot11FragmentationThreshold);
@@ -4618,6 +4641,9 @@  struct wiphy {
 	int n_akm_suites;
 	const u32 *akm_suites;
 
+	const struct wiphy_iftype_akm_suites *iftype_akm_suites;
+	unsigned int num_iftype_akm_suites;
+
 	u8 retry_short;
 	u8 retry_long;
 	u32 frag_threshold;
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 809ef9165684..108c039cc54b 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2402,6 +2402,11 @@  enum nl80211_commands {
  *
  * @NL80211_ATTR_HE_BSS_COLOR: nested attribute for BSS Color Settings.
  *
+ * @NL80211_ATTR_IFTYPE_AKM_SUITES: Used for AKM suite capability advertisement
+ *	per interface. This is a nested attribute of %NL80211_ATTR_AKM_SUITES
+ *	and %NL80211_ATTR_SUPPORTED_IFTYPE to specify supported AKMs per
+ *	interface type.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2868,6 +2873,8 @@  enum nl80211_attrs {
 
 	NL80211_ATTR_HE_BSS_COLOR,
 
+	NL80211_ATTR_IFTYPE_AKM_SUITES,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 00f24d4c623e..7dd0e622b2f1 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1893,6 +1893,46 @@  static int nl80211_send_pmsr_capa(struct cfg80211_registered_device *rdev,
 	return 0;
 }
 
+static int
+nl80211_put_iftype_akm_suites(struct cfg80211_registered_device *rdev,
+			      struct sk_buff *msg)
+{
+	int i;
+	struct nlattr *nested, *nested_akms;
+	const struct wiphy_iftype_akm_suites *iftype_akms;
+
+	if (!rdev->wiphy.num_iftype_akm_suites ||
+	    !rdev->wiphy.iftype_akm_suites)
+		return 0;
+
+	nested = nla_nest_start(msg, NL80211_ATTR_IFTYPE_AKM_SUITES);
+	if (!nested)
+		return -ENOBUFS;
+
+	for (i = 0; i < rdev->wiphy.num_iftype_akm_suites; i++) {
+		nested_akms = nla_nest_start(msg, i + 1);
+		if (!nested_akms)
+			return -ENOBUFS;
+
+		iftype_akms = &rdev->wiphy.iftype_akm_suites[i];
+
+		if (nl80211_put_iftypes(msg, NL80211_ATTR_SUPPORTED_IFTYPES,
+					iftype_akms->iftypes_mask))
+			return -ENOBUFS;
+
+		if (nla_put(msg, NL80211_ATTR_AKM_SUITES,
+			    sizeof(u32) * iftype_akms->n_akm_suites,
+			    iftype_akms->akm_suites)) {
+			return -ENOBUFS;
+		}
+		nla_nest_end(msg, nested_akms);
+	}
+
+	nla_nest_end(msg, nested);
+
+	return 0;
+}
+
 struct nl80211_dump_wiphy_state {
 	s64 filter_wiphy;
 	long start;
@@ -2451,6 +2491,9 @@  static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
 			    rdev->wiphy.akm_suites))
 			goto nla_put_failure;
 
+		if (nl80211_put_iftype_akm_suites(rdev, msg))
+			goto nla_put_failure;
+
 		/* done */
 		state->split_start = 0;
 		break;