[PATCH v2 3/4] nl80211: support SAE authentication offload in AP mode

[Chung-Hsien Hsu <stanley.hsu@cypress.com>]

Let drivers advertise support for AP-mode SAE authentication offload
with a new NL80211_EXT_FEATURE_SAE_OFFLOAD_AP flag.

Signed-off-by: Chung-Hsien Hsu <stanley.hsu@cypress.com>
Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
---
Chances in v2:
  - use a new flag for SAE offload in AP mode.
---
 include/uapi/linux/nl80211.h | 14 +++++++++++---
 net/wireless/nl80211.c       |  9 ++++++---
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 0d267ac3858c..038205fe19c3 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -252,9 +252,13 @@
  * DOC: SAE authentication offload
  *
  * By setting @NL80211_EXT_FEATURE_SAE_OFFLOAD flag drivers can indicate they
- * support offloading SAE authentication for WPA3-Personal networks. In
- * %NL80211_CMD_CONNECT the password for SAE should be specified using
- * %NL80211_ATTR_SAE_PASSWORD.
+ * support offloading SAE authentication for WPA3-Personal networks in station
+ * mode. Similarly @NL80211_EXT_FEATURE_SAE_OFFLOAD_AP flag can be set by
+ * drivers indicating the offload support in AP mode.
+ *
+ * The password for SAE should be specified using %NL80211_ATTR_SAE_PASSWORD in
+ * %NL80211_CMD_CONNECT and %NL80211_CMD_START_AP for station and AP mode
+ * respectively.
  */
 
 /**
@@ -5787,6 +5791,9 @@ enum nl80211_feature_flags {
  *	handshake with PSK in AP mode (PSK is passed as part of the start AP
  *	command).
  *
+ * @NL80211_EXT_FEATURE_SAE_OFFLOAD_AP: Device wants to do SAE authentication
+ *	in AP mode (SAE password is passed as part of the start AP command).
+ *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
  */
@@ -5843,6 +5850,7 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_SCAN_FREQ_KHZ,
 	NL80211_EXT_FEATURE_CONTROL_PORT_OVER_NL80211_TX_STATUS,
 	NL80211_EXT_FEATURE_4WAY_HANDSHAKE_AP_PSK,
+	NL80211_EXT_FEATURE_SAE_OFFLOAD_AP,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 8e7c6a022205..497f8ea231fd 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -4831,8 +4831,9 @@ static bool nl80211_valid_auth_type(struct cfg80211_registered_device *rdev,
 			return false;
 		return true;
 	case NL80211_CMD_START_AP:
-		/* SAE not supported yet */
-		if (auth_type == NL80211_AUTHTYPE_SAE)
+		if (!wiphy_ext_feature_isset(&rdev->wiphy,
+					     NL80211_EXT_FEATURE_SAE_OFFLOAD_AP) &&
+		    auth_type == NL80211_AUTHTYPE_SAE)
 			return false;
 		/* FILS not supported yet */
 		if (auth_type == NL80211_AUTHTYPE_FILS_SK ||
@@ -9447,7 +9448,9 @@ static int nl80211_crypto_settings(struct cfg80211_registered_device *rdev,
 
 	if (info->attrs[NL80211_ATTR_SAE_PASSWORD]) {
 		if (!wiphy_ext_feature_isset(&rdev->wiphy,
-					     NL80211_EXT_FEATURE_SAE_OFFLOAD))
+					     NL80211_EXT_FEATURE_SAE_OFFLOAD) &&
+		    !wiphy_ext_feature_isset(&rdev->wiphy,
+					     NL80211_EXT_FEATURE_SAE_OFFLOAD_AP))
 			return -EINVAL;
 		settings->sae_pwd =
 			nla_data(info->attrs[NL80211_ATTR_SAE_PASSWORD]);
-- 
2.25.0