[RFC v2 96/99] NAN: Add API to get peer elements

[Andrei Otcheretianski]

Add an API to get IEs included in peer's element container attribute.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski at intel.com>
---
 src/nan/nan.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++
 src/nan/nan.h |  1 +
 2 files changed, 68 insertions(+)

diff --git a/src/nan/nan.c b/src/nan/nan.c
index 1008cc9fa7..869f9fbac1 100644
--- a/src/nan/nan.c
+++ b/src/nan/nan.c
@@ -2247,3 +2247,70 @@ int nan_peer_del_all_ndps(struct nan_data *nan, const u8 *addr)
 
 	return 0;
 }
+
+
+/*
+ * nan_get_peer_elems - Get element container data for a peer
+ *
+ * @nan: NAN module context from nan_init()
+ * @addr: NAN MAC address of the peer
+ * @elems: On return, pointer to the element container data
+ * Return: Length of the element data on success; -1 on failure
+ *
+ * Retrieve the element container data associated with a peer. The function
+ * first looks for an entry with map_id 0. If not found and the peer has an
+ * active NDL, it returns the elements corresponding to the NDC channel's
+ * map_id. If no NDC map_id entry is found, it returns the first entry found.
+ */
+int nan_get_peer_elems(struct nan_data *nan, const u8 *addr, u8 **elems)
+{
+	struct nan_elem_container_entry *entry;
+	struct nan_peer *peer;
+	u8 ndc_map_id = 0;
+	bool ndc_map_id_found = false;
+
+	peer = nan_get_peer(nan, addr);
+	if (!peer)
+		return -1;
+
+	if (peer->ndl) {
+		struct nan_sched_entry *peer_ndc =
+			(void *)peer->ndl->ndc_sched;
+
+		if (peer_ndc &&
+		    peer->ndl->ndc_sched_len >= sizeof(*peer_ndc))
+			ndc_map_id = peer_ndc->map_id;
+	}
+
+	/* Prefer map_id == 0, so it applies for all */
+	dl_list_for_each(entry, &peer->info.element_container,
+			 struct nan_elem_container_entry, list) {
+		if (entry->map_id == 0) {
+			*elems = entry->data;
+			return entry->len;
+		}
+
+		if (ndc_map_id && entry->map_id == ndc_map_id)
+			ndc_map_id_found = true;
+	}
+
+	/*
+	 * TODO: Properly support different elements per map_id,
+	 * currently take the elements that correspond to the NDC
+	 * channel if available.
+	 * Currently upper layers don't support configuring different
+	 * elements per map_id. Until that is changed, take the map_id
+	 * corresponding to the NDC channel as it at least must intersect
+	 * with the local schedule. If no such entry exists, return the
+	 * first entry found.
+	 */
+	dl_list_for_each(entry, &peer->info.element_container,
+			 struct nan_elem_container_entry, list) {
+		if (!ndc_map_id_found || entry->map_id == ndc_map_id) {
+			*elems = entry->data;
+			return entry->len;
+		}
+	}
+
+	return -1;
+}
diff --git a/src/nan/nan.h b/src/nan/nan.h
index 3ddf47f2cb..e1cdc331fa 100644
--- a/src/nan/nan.h
+++ b/src/nan/nan.h
@@ -578,4 +578,5 @@ void nan_add_dev_capa_attr(struct nan_data *nan, struct wpabuf *buf);
 int nan_peer_del_all_ndps(struct nan_data *nan, const u8 *addr);
 int nan_get_chan_entry(struct nan_data *nan, const struct nan_sched_chan *chan,
 		       struct nan_chan_entry *chan_entry);
+int nan_get_peer_elems(struct nan_data *nan, const u8 *addr, u8 **elems);
 #endif /* NAN_H */
-- 
2.49.0