[RFC v2 20/99] NAN: Add support for adding availability attributes
Andrei Otcheretianski
andrei.otcheretianski at intel.com
Tue Dec 23 03:51:24 PST 2025
From: Ilan Peer <ilan.peer at intel.com>
Add support for constructing NAN availability attributes
from the NAN schedule.
---
src/nan/nan_i.h | 17 +++
src/nan/nan_ndl.c | 59 +++++++++++
src/nan/nan_util.c | 253 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 329 insertions(+)
diff --git a/src/nan/nan_i.h b/src/nan/nan_i.h
index a01d318fe7..5c48865b1b 100644
--- a/src/nan/nan_i.h
+++ b/src/nan/nan_i.h
@@ -16,6 +16,8 @@
struct nan_config;
+#define NAN_INVALID_MAP_ID 0xff
+
/*
* enum nan_ndp_state - State of NDP establishment
* @NAN_NDP_STATE_NONE: No NDP establishment in progress.
@@ -124,6 +126,11 @@ enum nan_band_chan_type {
NAN_TYPE_CHANNEL,
};
+/* Default availability entry parameter values */
+#define NAN_AVAIL_ENTRY_DEF_UTIL NAN_AVAIL_ENTRY_CTRL_UTIL_UNKNOWN
+#define NAN_AVAIL_ENTRY_DEF_NSS 2
+#define NAN_AVAIL_ENTRY_DEF_PREF 3
+
/*
* struct nan_avail_entry - NAN availability entry
*
@@ -414,4 +421,14 @@ int nan_chan_to_chan_idx_map(struct nan_data *nan,
u8 op_class, u8 channel, u16 *chan_idx_map);
int nan_ndl_naf_sent(struct nan_data *nan, struct nan_peer *peer,
enum nan_subtype subtype);
+int nan_ndl_add_avail_attrs(struct nan_data *nan,
+ const struct nan_peer *peer,
+ struct wpabuf *buf);
+int nan_get_chan_bm(struct nan_data *nan, struct nan_sched_chan *chan,
+ u8 *op_class, u16 *chan_bm, u16 *pri_chan_bm);
+int nan_add_avail_attrs(struct nan_data *nan, u8 sequence_id,
+ u32 map_ids_bitmap,
+ u8 type_for_conditional,
+ size_t n_chans, struct nan_chan_schedule *chans,
+ struct wpabuf *buf);
#endif
diff --git a/src/nan/nan_ndl.c b/src/nan/nan_ndl.c
index e3cb8f0ed3..afca5e55a2 100644
--- a/src/nan/nan_ndl.c
+++ b/src/nan/nan_ndl.c
@@ -8,6 +8,7 @@
#include "includes.h"
#include "common.h"
+#include "common/ieee802_11_common.h"
#include "nan_i.h"
struct ndl_attr_params {
@@ -862,6 +863,64 @@ int nan_ndl_handle_ndl_attr(struct nan_data *nan, struct nan_peer *peer,
}
}
+/*
+ * nan_ndl_add_avail_attrs - Add availability attributes
+ *
+ * @nan: NAN module context from nan_init()
+ * @peer: NAN peer for NDL establishment
+ * @buf: Frame buffer to which the attribute would be added
+ * Returns: 0 on success, negative on failure.
+ *
+ * An availability attribute is added for each map (identified by map ID) in the
+ * NDL schedule. Each attribute would hold an availability entry for committed
+ * slots and an availability entry for conditional slots.
+ */
+int nan_ndl_add_avail_attrs(struct nan_data *nan,
+ const struct nan_peer *peer,
+ struct wpabuf *buf)
+{
+ struct nan_schedule *sched;
+ u8 type_for_conditional = NAN_AVAIL_ENTRY_CTRL_TYPE_COND;
+
+ if (!peer || !peer->ndl)
+ return -1;
+
+ sched = &peer->ndl->sched;
+
+ wpa_printf(MSG_DEBUG,
+ "NAN: NDL: Add Avail attribute. state=%s, status=%u",
+ nan_ndl_state_str(peer->ndl->state), peer->ndl->status);
+
+ if (sched->n_chans < 1) {
+ if (peer->ndl->status == NAN_NDL_STATUS_REJECTED) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: NDL: Rejected. Not adding availability attributes");
+ return 0;
+ }
+
+ wpa_printf(MSG_DEBUG,
+ "NAN: NDL: Cannot build availability without channels");
+ return -1;
+ }
+
+ /* In case that NDL exchange was complete successfully,
+ * consider the conditional entries as committed, as
+ * this is expected by the spec.
+ */
+ if (peer->ndl->status == NAN_NDL_STATUS_ACCEPTED) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: NDL: Add conditional entry as committed");
+ type_for_conditional = NAN_AVAIL_ENTRY_CTRL_TYPE_COMMITTED;
+ }
+
+ return nan_add_avail_attrs(nan, sched->sequence_id,
+ sched->map_ids_bitmap,
+ type_for_conditional,
+ sched->n_chans,
+ sched->chans, buf);
+
+}
+
/*
* nan_ndl_add_ndl_attr - Add NDL attribute to frame
diff --git a/src/nan/nan_util.c b/src/nan/nan_util.c
index f7c35a3155..57414cdc37 100644
--- a/src/nan/nan_util.c
+++ b/src/nan/nan_util.c
@@ -367,3 +367,256 @@ int nan_chan_to_chan_idx_map(struct nan_data *nan,
*chan_idx_map = BIT(ret);
return 0;
}
+
+
+static u16 nan_add_avail_entry(struct nan_data *nan,
+ struct nan_time_bitmap *tbm,
+ u8 type, u8 op_class,
+ u16 chan_bm, u8 prim_chan_bm,
+ struct wpabuf *buf)
+{
+ u16 ctrl;
+ u8 chan_ctrl;
+ u8 *len_ptr;
+ u8 nss = BITS(nan->cfg->dev_capa.n_antennas, NAN_DEV_CAPA_RX_ANT_MASK,
+ NAN_DEV_CAPA_RX_ANT_POS);
+
+ len_ptr = wpabuf_put(buf, 2);
+
+ /*
+ * TODO: Need to also add potential entries as otherwise the peer would
+ * not be able to counter
+ */
+ if (type != NAN_AVAIL_ENTRY_CTRL_TYPE_COMMITTED &&
+ type != NAN_AVAIL_ENTRY_CTRL_TYPE_COND) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: Cannot add non committed/conditional entry");
+ return 0;
+ }
+
+ /*
+ * Add the entry control field
+ * - usage preference is not set for committed and conditional
+ * - utilization is max.
+ */
+ ctrl = type;
+ ctrl |= NAN_AVAIL_ENTRY_DEF_UTIL << NAN_AVAIL_ENTRY_CTRL_UTIL_POS;
+ ctrl |= nss << NAN_AVAIL_ENTRY_CTRL_RX_NSS_POS;
+ ctrl |= NAN_AVAIL_ENTRY_CTRL_TBM_PRESENT;
+ wpabuf_put_le16(buf, ctrl);
+
+ /* Add the time bitmap control field */
+ ctrl = tbm->duration << NAN_TIME_BM_CTRL_BIT_DURATION_POS;
+ ctrl |= tbm->period << NAN_TIME_BM_CTRL_PERIOD_POS;
+ ctrl |= tbm->offset << NAN_TIME_BM_CTRL_START_OFFSET_POS;
+ wpabuf_put_le16(buf, ctrl);
+
+ wpabuf_put_u8(buf, tbm->len);
+
+ wpabuf_put_data(buf, tbm->bitmap, tbm->len);
+
+ /* Add the channel entry: single contiguous channel entry */
+ chan_ctrl = NAN_BAND_CHAN_CTRL_TYPE;
+ chan_ctrl |= 1 << NAN_BAND_CHAN_CTRL_NUM_ENTRIES_POS;
+ wpabuf_put_u8(buf, chan_ctrl);
+ wpabuf_put_u8(buf, op_class);
+ wpabuf_put_le16(buf, chan_bm);
+ wpabuf_put_u8(buf, prim_chan_bm);
+
+ WPA_PUT_LE16(len_ptr, (u8 *)wpabuf_put(buf, 0) - len_ptr - 2);
+ return (u8 *)wpabuf_put(buf, 0) - len_ptr;
+}
+
+
+int nan_get_chan_bm(struct nan_data *nan, struct nan_sched_chan *chan,
+ u8 *op_class, u16 *chan_bm, u16 *pri_chan_bm)
+{
+ u8 bandwidth, channel;
+ enum hostapd_hw_mode mode;
+ int ret, sec_channel_offset;
+ int freq_offsset = chan->freq - chan->center_freq1;
+ u32 idx;
+
+ switch (chan->bandwidth) {
+ case 20:
+ case 40:
+ default:
+ bandwidth = CHANWIDTH_USE_HT;
+ break;
+ case 80:
+ bandwidth = CHANWIDTH_80MHZ;
+
+ idx = (freq_offsset + 30) / 20;
+ *pri_chan_bm = BIT(idx);
+ break;
+ case 160:
+ if (chan->center_freq2) {
+ bandwidth = CHANWIDTH_80P80MHZ;
+
+ /* TODO: Need to support auxiliary channel bitmap */
+ idx = (freq_offsset + 30) / 20;
+ *pri_chan_bm = BIT(idx);
+ } else {
+ bandwidth = CHANWIDTH_160MHZ;
+ idx = (freq_offsset + 70) / 20;
+ *pri_chan_bm = BIT(idx);
+ }
+ break;
+ }
+
+ if (freq_offsset > 0)
+ sec_channel_offset = 1;
+ else if (freq_offsset < 0)
+ sec_channel_offset = -1;
+ else
+ sec_channel_offset = 0;
+
+ /* For bandwidths >= 80 need to use the center frequency */
+ mode = ieee80211_freq_to_channel_ext(bandwidth == CHANWIDTH_USE_HT ?
+ chan->freq : chan->center_freq1,
+ sec_channel_offset,
+ bandwidth,
+ op_class, &channel);
+ if (mode == NUM_HOSTAPD_MODES) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: Cannot get channel and op_class");
+ return -1;
+ }
+
+ ret = nan_chan_to_chan_idx_map(nan, *op_class, channel, chan_bm);
+ if (ret) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: Failed to derive channel bitmap");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/**
+ * nan_add_avail_attrs - Add NAN availability attributes
+ * @nan: NAN module context from nan_init()
+ * @sequence_id: Sequence ID to be used in the availability attributes
+ * @map_ids_bitmap: Bitmap of map IDs to be included in the availability
+ * attributes
+ * @type_for_conditional: Type field to be used for conditional entries
+ * @n_chans: Number of channels in chans
+ * @chans: Channel schedules
+ * @buf: Frame buffer to which the attribute would be added
+ * Returns: 0 on success, negative on failure.
+ *
+ * An availability attribute is added for each map (identified by map ID) in the
+ * schedule. All channels with the same map ID are added to the same
+ * availability attribute. Each attribute will hold an availability entry for
+ * committed slots and an availability entry for conditional slots.
+ */
+int nan_add_avail_attrs(struct nan_data *nan, u8 sequence_id,
+ u32 map_ids_bitmap,
+ u8 type_for_conditional,
+ size_t n_chans, struct nan_chan_schedule *chans,
+ struct wpabuf *buf)
+{
+ u8 last_map_id = NAN_INVALID_MAP_ID;
+ u8 *len_ptr = NULL;
+ u8 i;
+
+ wpa_printf(MSG_DEBUG, "NAN: Add availability attrs. n_chans=%zu",
+ n_chans);
+
+ for (i = 0; i < n_chans; i++) {
+ struct nan_chan_schedule *chan = &chans[i];
+ u8 op_class;
+ u16 chan_bm, pri_chan_bm;
+ int ret;
+
+ if (!chan->conditional.len && !chan->committed.len) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: committed and conditional are empty");
+ continue;
+ }
+
+ ret = nan_get_chan_bm(nan, &chan->chan, &op_class,
+ &chan_bm, &pri_chan_bm);
+ if (ret)
+ continue;
+
+ /*
+ * All channels with the same map ID should be added to the same
+ * availability attribute, so verify that the map IDs are
+ * sorted.
+ */
+ if (last_map_id != NAN_INVALID_MAP_ID &&
+ last_map_id > chan->map_id) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: map IDs not sorted properly");
+ return -1;
+ }
+
+ if (!(map_ids_bitmap & BIT(chan->map_id))) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: skip adding availability for map_id=%u",
+ chan->map_id);
+ continue;
+ }
+
+ if (last_map_id != chan->map_id) {
+ u16 ctrl;
+
+ if (last_map_id != NAN_INVALID_MAP_ID) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: Add avail attr done: map_id=%u",
+ last_map_id);
+
+ WPA_PUT_LE16(len_ptr,
+ (u8 *)wpabuf_put(buf, 0) - len_ptr - 2);
+ }
+
+ last_map_id = chan->map_id;
+ map_ids_bitmap &= ~BIT(last_map_id);
+
+ wpa_printf(MSG_DEBUG, "NAN: Add avail attr map_id=%u",
+ last_map_id);
+
+ wpabuf_put_u8(buf, NAN_ATTR_NAN_AVAILABILITY);
+ len_ptr = wpabuf_put(buf, 2);
+ wpabuf_put_u8(buf, sequence_id);
+
+ ctrl = last_map_id << NAN_AVAIL_CTRL_MAP_ID_POS;
+
+ /*
+ * The spec states that this bit should be set if the
+ * committed changed or if conditional is included. Set
+ * it anyway, as it is not known what information the
+ * peer has on our schedule.
+ */
+ ctrl |= NAN_AVAIL_CTRL_COMMITTED_CHANGED;
+ wpabuf_put_le16(buf, ctrl);
+ }
+
+ /* TODO: handle primary channel configuration */
+ if (chan->committed.len)
+ nan_add_avail_entry(nan, &chan->committed,
+ NAN_AVAIL_ENTRY_CTRL_TYPE_COMMITTED,
+ op_class, chan_bm, pri_chan_bm,
+ buf);
+
+ if (chan->conditional.len)
+ nan_add_avail_entry(nan, &chan->conditional,
+ type_for_conditional,
+ op_class, chan_bm, 0, buf);
+ }
+
+ if (last_map_id == NAN_INVALID_MAP_ID) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: No valid availability entries added");
+ return -1;
+ }
+
+ wpa_printf(MSG_DEBUG, "NAN: Add avail attr done: map_id=%u",
+ last_map_id);
+
+ WPA_PUT_LE16(len_ptr, (u8 *)wpabuf_put(buf, 0) - len_ptr - 2);
+
+ return 0;
+}
--
2.49.0
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