nl80211: Use the new NL80211_MFP_OPTIONAL option

Now we can configure the network block so that it allows MFP setting for
the NL80211_CMD_CONNECT command. If the kernel finds an AP that requires
MFP, it'll be able to connect to it.

Note that since NL80211_MFP_OPTIONAL isn't supported for
NL80211_CMD_ASSOCIATE, we need to take the MFP configuration outside
nl80211_connect_common(). In addition, check that
NL80211_EXT_FEATURE_MFP_OPTIONAL is supported, to be backward compatible
with older kernels.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

src/drivers/driver.h

@@ -1563,6 +1563,8 @@ struct wpa_driver_capa {
  * functionality but can support only OCE STA-CFON functionality.
  */
 #define WPA_DRIVER_FLAGS_OCE_STA_CFON		0x0020000000000000ULL
+/** Driver supports MFP-optional in the connect command */
+#define WPA_DRIVER_FLAGS_MFP_OPTIONAL		0x0040000000000000ULL
 	u64 flags;
 
 #define FULL_AP_CLIENT_STATE_SUPP(drv_flags) \

src/drivers/driver_nl80211.c

@@ -5408,10 +5408,6 @@ static int nl80211_connect_common(struct wpa_driver_nl80211_data *drv,
 	     nla_put_flag(msg, NL80211_ATTR_CONTROL_PORT_NO_ENCRYPT)))
 		return -1;
 
-	if (params->mgmt_frame_protection == MGMT_FRAME_PROTECTION_REQUIRED &&
-	    nla_put_u32(msg, NL80211_ATTR_USE_MFP, NL80211_MFP_REQUIRED))
-		return -1;
-
 	if (params->rrm_used) {
 		u32 drv_rrm_flags = drv->capa.rrm_flags;
 		if ((!((drv_rrm_flags &
@@ -5488,6 +5484,15 @@ static int wpa_driver_nl80211_try_connect(
 	if (ret)
 		goto fail;
 
+	if (params->mgmt_frame_protection == MGMT_FRAME_PROTECTION_REQUIRED &&
+	    nla_put_u32(msg, NL80211_ATTR_USE_MFP, NL80211_MFP_REQUIRED))
+		goto fail;
+
+	if (params->mgmt_frame_protection == MGMT_FRAME_PROTECTION_OPTIONAL &&
+	    (drv->capa.flags & WPA_DRIVER_FLAGS_MFP_OPTIONAL) &&
+	    nla_put_u32(msg, NL80211_ATTR_USE_MFP, NL80211_MFP_OPTIONAL))
+		goto fail;
+
 	algs = 0;
 	if (params->auth_alg & WPA_AUTH_ALG_OPEN)
 		algs++;
@@ -5607,6 +5612,10 @@ static int wpa_driver_nl80211_associate(
 	if (ret)
 		goto fail;
 
+	if (params->mgmt_frame_protection == MGMT_FRAME_PROTECTION_REQUIRED &&
+	    nla_put_u32(msg, NL80211_ATTR_USE_MFP, NL80211_MFP_REQUIRED))
+		goto fail;
+
 	if (params->fils_kek) {
 		wpa_printf(MSG_DEBUG, "  * FILS KEK (len=%u)",
 			   (unsigned int) params->fils_kek_len);

src/drivers/driver_nl80211_capa.c

@@ -407,6 +407,10 @@ static void wiphy_info_ext_feature_flags(struct wiphy_info_data *info,
 	    ext_feature_isset(ext_features, len,
 			      NL80211_EXT_FEATURE_4WAY_HANDSHAKE_STA_1X))
 		capa->flags |= WPA_DRIVER_FLAGS_4WAY_HANDSHAKE;
+
+	if (ext_feature_isset(ext_features, len,
+			      NL80211_EXT_FEATURE_MFP_OPTIONAL))
+		capa->flags |= WPA_DRIVER_FLAGS_MFP_OPTIONAL;
 }