wifi: nl80211: support MLO in auth/assoc

For authentication, we need the BSS, the link_id and the AP
MLD address to create the link and station, (for now) the
driver assigns a link address and sends the frame, the MLD
address needs to be the address of the interface.

For association, pass the list of BSSes that were selected
for the MLO connection, along with extra per-STA profile
elements, the AP MLD address and the link ID on which the
association request should be sent.

Note that for now we don't have a proper way to pass the link
address(es) and so the driver/mac80211 will select one, but
depending on how that selection works it means that assoc w/o
auth data still being around (mac80211 implementation detail)
the association won't necessarily work - so this will need to
be extended in the future to sort out the link addressing.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 117 insertions, 6 deletions

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 532113937469..d92eed0e52cd 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -241,6 +241,10 @@ int cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
 	if (!req->bss)
 		return -ENOENT;
 
+	if (req->link_id >= 0 &&
+	    !(wdev->wiphy->flags & WIPHY_FLAG_SUPPORTS_MLO))
+		return -EINVAL;
+
 	if (req->auth_type == NL80211_AUTHTYPE_SHARED_KEY) {
 		if (!req->key || !req->key_len ||
 		    req->key_idx < 0 || req->key_idx > 3)
@@ -294,10 +298,19 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 			struct cfg80211_assoc_request *req)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
-	int err;
+	int err, i, j;
 
 	ASSERT_WDEV_LOCK(wdev);
 
+	for (i = 1; i < ARRAY_SIZE(req->links); i++) {
+		if (!req->links[i].bss)
+			continue;
+		for (j = 0; j < i; j++) {
+			if (req->links[i].bss == req->links[j].bss)
+				return -EINVAL;
+		}
+	}
+
 	if (wdev->connected &&
 	    (!req->prev_bssid ||
 	     !ether_addr_equal(wdev->u.client.connected_addr, req->prev_bssid)))
@@ -310,8 +323,19 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 
 	err = rdev_assoc(rdev, dev, req);
 	if (!err) {
-		cfg80211_ref_bss(&rdev->wiphy, req->bss);
-		cfg80211_hold_bss(bss_from_pub(req->bss));
+		int link_id;
+
+		if (req->bss) {
+			cfg80211_ref_bss(&rdev->wiphy, req->bss);
+			cfg80211_hold_bss(bss_from_pub(req->bss));
+		}
+
+		for (link_id = 0; link_id < ARRAY_SIZE(req->links); link_id++) {
+			if (!req->links[link_id].bss)
+				continue;
+			cfg80211_ref_bss(&rdev->wiphy, req->links[link_id].bss);
+			cfg80211_hold_bss(bss_from_pub(req->links[link_id].bss));
+		}
 	}
 	return err;
 }
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 5a4d3ddcdf80..9bc66a21ac3a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -796,6 +796,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 		NLA_POLICY_NESTED_ARRAY(nl80211_policy),
 	[NL80211_ATTR_MLO_LINK_ID] =
 		NLA_POLICY_RANGE(NLA_U8, 0, IEEE80211_MLD_MAX_NUM_LINKS),
+	[NL80211_ATTR_MLD_ADDR] = NLA_POLICY_EXACT_LEN(ETH_ALEN),
 };
 
 /* policy for the key attributes */
@@ -10282,6 +10283,12 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 	req.key = key.p.key;
 	req.key_len = key.p.key_len;
 	req.key_idx = key.idx;
+	req.link_id = nl80211_link_id_or_invalid(info->attrs);
+	if (req.link_id >= 0) {
+		if (!info->attrs[NL80211_ATTR_MLD_ADDR])
+			return -EINVAL;
+		req.ap_mld_addr = nla_data(info->attrs[NL80211_ATTR_MLD_ADDR]);
+	}
 
 	req.bss = cfg80211_get_bss(&rdev->wiphy, chan, bssid, ssid, ssid_len,
 				   IEEE80211_BSS_TYPE_ESS,
@@ -10475,7 +10482,9 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
 	struct net_device *dev = info->user_ptr[1];
 	struct cfg80211_assoc_request req = {};
+	struct nlattr **attrs = NULL;
 	const u8 *bssid, *ssid;
+	unsigned int link_id;
 	int err, ssid_len;
 
 	if (dev->ieee80211_ptr->conn_owner_nlportid &&
@@ -10585,9 +10594,81 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 		       sizeof(req.s1g_capa));
 	}
 
-	req.bss = nl80211_assoc_bss(rdev, ssid, ssid_len, info->attrs, &bssid);
-	if (IS_ERR(req.bss))
-		return PTR_ERR(req.bss);
+	req.link_id = nl80211_link_id_or_invalid(info->attrs);
+
+	if (info->attrs[NL80211_ATTR_MLO_LINKS]) {
+		unsigned int attrsize = NUM_NL80211_ATTR * sizeof(*attrs);
+		struct nlattr *link;
+		int rem = 0;
+
+		if (req.link_id < 0)
+			return -EINVAL;
+
+		if (!(rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_MLO))
+			return -EINVAL;
+
+		if (info->attrs[NL80211_ATTR_MAC] ||
+		    info->attrs[NL80211_ATTR_WIPHY_FREQ] ||
+		    !info->attrs[NL80211_ATTR_MLD_ADDR])
+			return -EINVAL;
+
+		req.ap_mld_addr = nla_data(info->attrs[NL80211_ATTR_MLD_ADDR]);
+
+		attrs = kzalloc(attrsize, GFP_KERNEL);
+		if (!attrs)
+			return -ENOMEM;
+
+		nla_for_each_nested(link,
+				    info->attrs[NL80211_ATTR_MLO_LINKS],
+				    rem) {
+			memset(attrs, 0, attrsize);
+
+			nla_parse_nested(attrs, NL80211_ATTR_MAX,
+					 link, NULL, NULL);
+
+			if (!attrs[NL80211_ATTR_MLO_LINK_ID]) {
+				err = -EINVAL;
+				goto free;
+			}
+
+			link_id = nla_get_u8(attrs[NL80211_ATTR_MLO_LINK_ID]);
+			/* cannot use the same link ID again */
+			if (req.links[link_id].bss) {
+				err = -EINVAL;
+				goto free;
+			}
+			req.links[link_id].bss =
+				nl80211_assoc_bss(rdev, ssid, ssid_len, attrs,
+						  &bssid);
+			if (IS_ERR(req.links[link_id].bss)) {
+				err = PTR_ERR(req.links[link_id].bss);
+				goto free;
+			}
+
+			if (attrs[NL80211_ATTR_IE]) {
+				req.links[link_id].elems =
+					nla_data(attrs[NL80211_ATTR_IE]);
+				req.links[link_id].elems_len =
+					nla_len(attrs[NL80211_ATTR_IE]);
+			}
+		}
+
+		if (!req.links[req.link_id].bss) {
+			err = -EINVAL;
+			goto free;
+		}
+
+		kfree(attrs);
+		attrs = NULL;
+	} else {
+		if (req.link_id >= 0)
+			return -EINVAL;
+
+		req.bss = nl80211_assoc_bss(rdev, ssid, ssid_len, info->attrs,
+					    &bssid);
+		if (IS_ERR(req.bss))
+			return PTR_ERR(req.bss);
+	}
 
 	err = nl80211_crypto_settings(rdev, info, &req.crypto, 1);
 	if (!err) {
@@ -10605,7 +10686,11 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 		wdev_unlock(dev->ieee80211_ptr);
 	}
 
+free:
+	for (link_id = 0; link_id < ARRAY_SIZE(req.links); link_id++)
+		cfg80211_put_bss(&rdev->wiphy, req.links[link_id].bss);
 	cfg80211_put_bss(&rdev->wiphy, req.bss);
+	kfree(attrs);
 
 	return err;
 }
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index c8a99b90723b..b3c6ce4f85ee 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -177,6 +177,7 @@ static int cfg80211_conn_do_work(struct wireless_dev *wdev,
 						params->ssid, params->ssid_len,
 						IEEE80211_BSS_TYPE_ESS,
 						IEEE80211_PRIVACY_ANY);
+		auth_req.link_id = -1;
 		err = cfg80211_mlme_auth(rdev, wdev->netdev, &auth_req);
 		cfg80211_put_bss(&rdev->wiphy, auth_req.bss);
 		return err;
@@ -198,6 +199,7 @@ static int cfg80211_conn_do_work(struct wireless_dev *wdev,
 		req.ht_capa_mask = params->ht_capa_mask;
 		req.vht_capa = params->vht_capa;
 		req.vht_capa_mask = params->vht_capa_mask;
+		req.link_id = -1;
 
 		req.bss = cfg80211_get_bss(&rdev->wiphy, params->channel,
 					   params->bssid,