wifi: mac80211: properly implement MLO key handling

Implement key installation and lookup (on TX and RX)
for MLO, so we can use multiple GTKs/IGTKs/BIGTKs.

Co-authored-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 46 insertions, 10 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 45df9932d0ba..8683f24aaec5 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -576,6 +576,51 @@ ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
 	return TX_CONTINUE;
 }
 
+static struct ieee80211_key *
+ieee80211_select_link_key(struct ieee80211_tx_data *tx)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
+	enum {
+		USE_NONE,
+		USE_MGMT_KEY,
+		USE_MCAST_KEY,
+	} which_key = USE_NONE;
+	struct ieee80211_link_data *link;
+	unsigned int link_id;
+
+	if (ieee80211_is_group_privacy_action(tx->skb))
+		which_key = USE_MCAST_KEY;
+	else if (ieee80211_is_mgmt(hdr->frame_control) &&
+		 is_multicast_ether_addr(hdr->addr1) &&
+		 ieee80211_is_robust_mgmt_frame(tx->skb))
+		which_key = USE_MGMT_KEY;
+	else if (is_multicast_ether_addr(hdr->addr1))
+		which_key = USE_MCAST_KEY;
+	else
+		return NULL;
+
+	link_id = u32_get_bits(info->control.flags, IEEE80211_TX_CTRL_MLO_LINK);
+	if (link_id == IEEE80211_LINK_UNSPECIFIED) {
+		link = &tx->sdata->deflink;
+	} else {
+		link = rcu_dereference(tx->sdata->link[link_id]);
+		if (!link)
+			return NULL;
+	}
+
+	switch (which_key) {
+	case USE_NONE:
+		break;
+	case USE_MGMT_KEY:
+		return rcu_dereference(link->default_mgmt_key);
+	case USE_MCAST_KEY:
+		return rcu_dereference(link->default_multicast_key);
+	}
+
+	return NULL;
+}
+
 static ieee80211_tx_result debug_noinline
 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
 {
@@ -591,16 +636,7 @@ ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
 	if (tx->sta &&
 	    (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
 		tx->key = key;
-	else if (ieee80211_is_group_privacy_action(tx->skb) &&
-		(key = rcu_dereference(tx->sdata->deflink.default_multicast_key)))
-		tx->key = key;
-	else if (ieee80211_is_mgmt(hdr->frame_control) &&
-		 is_multicast_ether_addr(hdr->addr1) &&
-		 ieee80211_is_robust_mgmt_frame(tx->skb) &&
-		 (key = rcu_dereference(tx->sdata->deflink.default_mgmt_key)))
-		tx->key = key;
-	else if (is_multicast_ether_addr(hdr->addr1) &&
-		 (key = rcu_dereference(tx->sdata->deflink.default_multicast_key)))
+	else if ((key = ieee80211_select_link_key(tx)))
 		tx->key = key;
 	else if (!is_multicast_ether_addr(hdr->addr1) &&
 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))