wifi: mac80211: support MLO authentication/association with one link

It might seem a bit pointless to do a multi-link operation
connection with just a single link, but this is already a
big change, so for now, limit MLO connections to a single
link.

Extending that to multiple links will require
 * work on parsing the multi-link element with STA profile
   properly, including element fragmentation;
 * checking the per-link status in the multi-link element
 * implementing logic to have active/inactive links to let
   drivers decide which links should be active;
 * implementing multicast RX deduplication;
 * and likely more.

For now this is still useful since it lets us do multi-link
connections for the purposes of testing APIs and the higher
layers such as wpa_supplicant.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/ieee80211_i.h

@@ -389,37 +389,55 @@ struct ieee80211_mgd_auth_data {
 	bool peer_confirmed;
 	bool timeout_started;
 
+	u8 ap_addr[ETH_ALEN] __aligned(2);
+
 	u16 sae_trans, sae_status;
 	size_t data_len;
 	u8 data[];
 };
 
 struct ieee80211_mgd_assoc_data {
-	struct cfg80211_bss *bss;
+	struct {
+		struct cfg80211_bss *bss;
+
+		u8 addr[ETH_ALEN] __aligned(2);
+
+		u8 ap_ht_param;
+
+		struct ieee80211_vht_cap ap_vht_cap;
+
+		size_t elems_len;
+		u8 *elems; /* pointing to inside ie[] below */
+
+		ieee80211_conn_flags_t conn_flags;
+	} link[IEEE80211_MLD_MAX_NUM_LINKS];
+
+	u8 ap_addr[ETH_ALEN] __aligned(2);
+
+	/* this is for a workaround, so we use it only for non-MLO */
 	const u8 *supp_rates;
+	u8 supp_rates_len;
 
 	unsigned long timeout;
 	int tries;
 
-	u16 capability;
-	u8 prev_bssid[ETH_ALEN];
+	u8 prev_ap_addr[ETH_ALEN];
 	u8 ssid[IEEE80211_MAX_SSID_LEN];
 	u8 ssid_len;
-	u8 supp_rates_len;
 	bool wmm, uapsd;
 	bool need_beacon;
 	bool synced;
 	bool timeout_started;
+	bool s1g;
 
-	u8 ap_ht_param;
-
-	struct ieee80211_vht_cap ap_vht_cap;
+	unsigned int assoc_link_id;
 
 	u8 fils_nonces[2 * FILS_NONCE_LEN];
 	u8 fils_kek[FILS_MAX_KEK_LEN];
 	size_t fils_kek_len;
 
 	size_t ie_len;
+	u8 *ie_pos; /* used to fill ie[] with link[].elems */
 	u8 ie[];
 };
 

net/mac80211/tx.c

@@ -2478,7 +2478,7 @@ int ieee80211_lookup_ra_sta(struct ieee80211_sub_if_data *sdata,
 
 		}
 
-		sta = sta_info_get(sdata, sdata->deflink.u.mgd.bssid);
+		sta = sta_info_get(sdata, sdata->vif.cfg.ap_addr);
 		if (!sta)
 			return -ENOLINK;
 		break;

net/wireless/mlme.c

@@ -50,6 +50,9 @@ void cfg80211_rx_assoc_resp(struct net_device *dev,
 		/* need to have local link addresses for MLO connections */
 		WARN_ON(cr.ap_mld_addr && !cr.links[link_id].addr);
 
+		printk(KERN_CRIT "BSS pointer 0x%lx\n", (unsigned long)cr.links[link_id].bss);
+		BUG_ON(!cr.links[link_id].bss->channel);
+
 		if (cr.links[link_id].bss->channel->band == NL80211_BAND_S1GHZ) {
 			WARN_ON(link_id);
 			cr.resp_ie = (u8 *)&mgmt->u.s1g_assoc_resp.variable;