nl80211: add a parameter for using 4-address frames on virtual interfaces

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/linux/nl80211.h

@@ -584,6 +584,8 @@ enum nl80211_commands {
  *	changed then the list changed and the dump should be repeated
  *	completely from scratch.
  *
+ * @NL80211_ATTR_4ADDR: Use 4-address frames on a virtual interface
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -714,6 +716,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_PID,
 
+	NL80211_ATTR_4ADDR,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,

include/net/cfg80211.h

@@ -206,10 +206,12 @@ struct ieee80211_supported_band {
  * struct vif_params - describes virtual interface parameters
  * @mesh_id: mesh ID to use
  * @mesh_id_len: length of the mesh ID
+ * @use_4addr: use 4-address frames
  */
 struct vif_params {
        u8 *mesh_id;
        int mesh_id_len;
+       int use_4addr;
 };
 
 /**

net/wireless/nl80211.c

@@ -138,6 +138,7 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
 	[NL80211_ATTR_CIPHER_SUITE_GROUP] = { .type = NLA_U32 },
 	[NL80211_ATTR_WPA_VERSIONS] = { .type = NLA_U32 },
 	[NL80211_ATTR_PID] = { .type = NLA_U32 },
+	[NL80211_ATTR_4ADDR] = { .type = NLA_U8 },
 };
 
 /* policy for the attributes */
@@ -987,6 +988,13 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
 		change = true;
 	}
 
+	if (info->attrs[NL80211_ATTR_4ADDR]) {
+		params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
+		change = true;
+	} else {
+		params.use_4addr = -1;
+	}
+
 	if (info->attrs[NL80211_ATTR_MNTR_FLAGS]) {
 		if (ntype != NL80211_IFTYPE_MONITOR) {
 			err = -EINVAL;
@@ -1053,6 +1061,9 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 		params.mesh_id_len = nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
 	}
 
+	if (info->attrs[NL80211_ATTR_4ADDR])
+		params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
+
 	err = parse_monitor_flags(type == NL80211_IFTYPE_MONITOR ?
 				  info->attrs[NL80211_ATTR_MNTR_FLAGS] : NULL,
 				  &flags);