wifi: mac80211_hwsim: Add simulation support for NAN device

Add support for simulating a NAN Device interface:

- Update interface limits to include support for NAN Device.
- Increase the number of supported HW addresses to allow unique
addresses for combination such as: station interface + P2P
Device interface + NAN Device interface.
- Declare support for NAN capabilities, specifically support for
NAN synchronization offload and NAN DE user space support.
- Add the relevant callbacks to support start/stop NAN Device
operation.
- Use a timer to simulate starting a Discovery Window (currently
the timer doesn't do much).
- Update the Tx path to simulate that the channel used for NAN
Device is either channel 6 or channel 149.
- Send DW notification when DW starts.
- Send cluster join notification when new cluster starts, or when an
existing cluster is joined. "Joining" is implemented by reusing the
cluster id of any other existing NAN management interface.

Signed-off-by: Ilan Peer <[e-mail]>
Signed-off-by: Miri Korenblit <[e-mail]>
Link: https://patch.msgid.link/20250908140015.2d02d5be6468.I3badfdb80c29e7713bd37373650ccbf099547a59@changeid
Signed-off-by: Johannes Berg <[e-mail]>

drivers/net/wireless/virtual/mac80211_hwsim.c

···
 static struct rhashtable hwsim_radios_rht;
 static int hwsim_radio_idx;
 static int hwsim_radios_generation = 1;
+static u8 hwsim_nan_cluster_id[ETH_ALEN];
 
 static struct platform_driver mac80211_hwsim_driver = {
 	.driver = {
···
 	struct ieee80211_channel channels_s1g[ARRAY_SIZE(hwsim_channels_s1g)];
 	struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];
 	struct ieee80211_iface_combination if_combination;
-	struct ieee80211_iface_limit if_limits[3];
+	struct ieee80211_iface_limit if_limits[4];
 	int n_if_limits;
 
 	struct ieee80211_iface_combination if_combination_radio;
···
 
 	u32 ciphers[ARRAY_SIZE(hwsim_ciphers)];
 
-	struct mac_address addresses[2];
+	struct mac_address addresses[3];
 	int channels, idx;
 	bool use_chanctx;
 	bool destroy_on_close;
···
 	struct wireless_dev *pmsr_request_wdev;
 
 	struct mac80211_hwsim_link_data link_data[IEEE80211_MLD_MAX_NUM_LINKS];
+
+	struct ieee80211_vif *nan_device_vif;
+	u8 nan_bands;
+
+	enum nl80211_band nan_curr_dw_band;
+	struct hrtimer nan_timer;
+	bool notify_dw;
+	struct ieee80211_vif *nan_vif;
 };
 
 static const struct rhashtable_params hwsim_rht_params = {
···
 	[HWSIM_ATTR_PMSR_SUPPORT] = NLA_POLICY_NESTED(hwsim_pmsr_capa_policy),
 	[HWSIM_ATTR_PMSR_RESULT] = NLA_POLICY_NESTED(hwsim_pmsr_peers_result_policy),
 	[HWSIM_ATTR_MULTI_RADIO] = { .type = NLA_FLAG },
+	[HWSIM_ATTR_SUPPORT_NAN_DEVICE] = { .type = NLA_FLAG },
 };
 
 #if IS_REACHABLE(CONFIG_VIRTIO)
···
 	struct tx_iter_data *data = _data;
 	int i;
 
+	/* For NAN Device simulation purposes, assume that NAN is always
+	 * on channel 6 or channel 149.
+	 */
+	if (vif->type == NL80211_IFTYPE_NAN) {
+		data->receive = (data->channel &&
+				 (data->channel->center_freq == 2437 ||
+				  data->channel->center_freq == 5745));
+		return;
+	}
+
 	for (i = 0; i < ARRAY_SIZE(vif->link_conf); i++) {
 		struct ieee80211_bss_conf *conf;
 		struct ieee80211_chanctx_conf *chanctx;
···
 	struct ieee80211_hdr *hdr = (void *)skb->data;
 	struct ieee80211_chanctx_conf *chanctx_conf;
 	struct ieee80211_channel *channel;
+	struct ieee80211_vif *vif = txi->control.vif;
 	bool ack;
 	enum nl80211_chan_width confbw = NL80211_CHAN_WIDTH_20_NOHT;
 	u32 _portid, i;
···
 		return;
 	}
 
-	if (!data->use_chanctx) {
+	if (vif && vif->type == NL80211_IFTYPE_NAN && !data->tmp_chan) {
+		/* For NAN Device simulation purposes, assume that NAN is always
+		 * on channel 6 or channel 149, unless a ROC is in progress (for
+		 * USD use cases).
+		 */
+		if (data->nan_curr_dw_band == NL80211_BAND_2GHZ)
+			channel = ieee80211_get_channel(hw->wiphy, 2437);
+		else if (data->nan_curr_dw_band == NL80211_BAND_5GHZ)
+			channel = ieee80211_get_channel(hw->wiphy, 5745);
+		else
+			channel = NULL;
+
+		if (WARN_ON(!channel)) {
+			ieee80211_free_txskb(hw, skb);
+			return;
+		}
+	} else if (!data->use_chanctx) {
 		channel = data->channel;
 		confbw = data->bw;
 	} else if (txi->hw_queue == 4) {
···
 	} else {
 		u8 link = u32_get_bits(IEEE80211_SKB_CB(skb)->control.flags,
 				       IEEE80211_TX_CTRL_MLO_LINK);
-		struct ieee80211_vif *vif = txi->control.vif;
 		struct ieee80211_link_sta *link_sta = NULL;
 		struct ieee80211_sta *sta = control->sta;
 		struct ieee80211_bss_conf *bss_conf;
···
 	return err;
 }
 
+static enum hrtimer_restart
+mac80211_hwsim_nan_dw_start(struct hrtimer *timer)
+{
+	struct mac80211_hwsim_data *data =
+		container_of(timer, struct mac80211_hwsim_data,
+			     nan_timer);
+	struct ieee80211_hw *hw = data->hw;
+	u64 orig_tsf = mac80211_hwsim_get_tsf(hw, NULL), tsf = orig_tsf;
+	u32 dw_int = 512 * 1024;
+	u64 until_dw;
+
+	if (!data->nan_device_vif)
+		return HRTIMER_NORESTART;
+
+	if (data->nan_bands & BIT(NL80211_BAND_5GHZ)) {
+		if (data->nan_curr_dw_band == NL80211_BAND_2GHZ) {
+			dw_int = 128 * 1024;
+			data->nan_curr_dw_band = NL80211_BAND_5GHZ;
+		} else if (data->nan_curr_dw_band == NL80211_BAND_5GHZ) {
+			data->nan_curr_dw_band = NL80211_BAND_2GHZ;
+		}
+	}
+
+	until_dw = dw_int - do_div(tsf, dw_int);
+
+	/* The timer might fire just before the actual DW, in which case
+	 * update the timeout to the actual next DW
+	 */
+	if (until_dw < dw_int / 2)
+		until_dw += dw_int;
+
+	/* The above do_div() call directly modifies the 'tsf' variable, thus,
+	 * use a copy so that the print below would show the original TSF.
+	 */
+	wiphy_debug(hw->wiphy,
+		    "%s: tsf=%llx, curr_dw_band=%u, next_dw=%llu\n",
+		    __func__, orig_tsf, data->nan_curr_dw_band,
+		    until_dw);
+
+	hrtimer_forward_now(&data->nan_timer,
+			    ns_to_ktime(until_dw * NSEC_PER_USEC));
+
+	if (data->notify_dw) {
+		struct ieee80211_channel *ch;
+		struct wireless_dev *wdev =
+			ieee80211_vif_to_wdev(data->nan_device_vif);
+
+		if (data->nan_curr_dw_band == NL80211_BAND_5GHZ)
+			ch = ieee80211_get_channel(hw->wiphy, 5475);
+		else
+			ch = ieee80211_get_channel(hw->wiphy, 2437);
+
+		cfg80211_next_nan_dw_notif(wdev, ch, GFP_ATOMIC);
+	}
+
+	return HRTIMER_RESTART;
+}
+
+static int mac80211_hwsim_start_nan(struct ieee80211_hw *hw,
+				    struct ieee80211_vif *vif,
+				    struct cfg80211_nan_conf *conf)
+{
+	struct mac80211_hwsim_data *data = hw->priv;
+	u64 tsf = mac80211_hwsim_get_tsf(hw, NULL);
+	u32 dw_int = 512 * 1000;
+	u64 until_dw = dw_int - do_div(tsf, dw_int);
+	struct wireless_dev *wdev = ieee80211_vif_to_wdev(vif);
+
+	if (vif->type != NL80211_IFTYPE_NAN)
+		return -EINVAL;
+
+	if (data->nan_device_vif)
+		return -EALREADY;
+
+	/* set this before starting the timer, as preemption might occur */
+	data->nan_device_vif = vif;
+	data->nan_bands = conf->bands;
+	data->nan_curr_dw_band = NL80211_BAND_2GHZ;
+
+	wiphy_debug(hw->wiphy, "nan_started, next_dw=%llu\n",
+		    until_dw);
+
+	hrtimer_start(&data->nan_timer,
+		      ns_to_ktime(until_dw * NSEC_PER_USEC),
+		      HRTIMER_MODE_REL_SOFT);
+
+	if (conf->cluster_id && !is_zero_ether_addr(conf->cluster_id) &&
+	    is_zero_ether_addr(hwsim_nan_cluster_id)) {
+		memcpy(hwsim_nan_cluster_id, conf->cluster_id, ETH_ALEN);
+	} else if (is_zero_ether_addr(hwsim_nan_cluster_id)) {
+		hwsim_nan_cluster_id[0] = 0x50;
+		hwsim_nan_cluster_id[1] = 0x6f;
+		hwsim_nan_cluster_id[2] = 0x9a;
+		hwsim_nan_cluster_id[3] = 0x01;
+		hwsim_nan_cluster_id[4] = get_random_u8();
+		hwsim_nan_cluster_id[5] = get_random_u8();
+	}
+
+	data->notify_dw = conf->enable_dw_notification;
+
+	cfg80211_nan_cluster_joined(wdev, hwsim_nan_cluster_id, true,
+				    GFP_KERNEL);
+
+	return 0;
+}
+
+static int mac80211_hwsim_stop_nan(struct ieee80211_hw *hw,
+				   struct ieee80211_vif *vif)
+{
+	struct mac80211_hwsim_data *data = hw->priv;
+	struct mac80211_hwsim_data *data2;
+	bool nan_cluster_running = false;
+
+	if (vif->type != NL80211_IFTYPE_NAN || !data->nan_device_vif ||
+	    data->nan_device_vif != vif)
+		return -EINVAL;
+
+	hrtimer_cancel(&data->nan_timer);
+	data->nan_device_vif = NULL;
+
+	spin_lock(&hwsim_radio_lock);
+	list_for_each_entry(data2, &hwsim_radios, list) {
+		if (data2->nan_device_vif) {
+			nan_cluster_running = true;
+			break;
+		}
+	}
+	spin_unlock(&hwsim_radio_lock);
+
+	if (!nan_cluster_running)
+		memset(hwsim_nan_cluster_id, 0, ETH_ALEN);
+
+	return 0;
+}
+
+static int mac80211_hwsim_change_nan_config(struct ieee80211_hw *hw,
+					    struct ieee80211_vif *vif,
+					    struct cfg80211_nan_conf *conf,
+					    u32 changes)
+{
+	struct mac80211_hwsim_data *data = hw->priv;
+
+	if (vif->type != NL80211_IFTYPE_NAN)
+		return -EINVAL;
+
+	if (!data->nan_device_vif)
+		return -EINVAL;
+
+	wiphy_debug(hw->wiphy, "nan_config_changed: changes=0x%x\n", changes);
+
+	/* Handle only the changes we care about for simulation purposes */
+	if (changes & CFG80211_NAN_CONF_CHANGED_BANDS) {
+		data->nan_bands = conf->bands;
+		data->nan_curr_dw_band = NL80211_BAND_2GHZ;
+	}
+
+	if (changes & CFG80211_NAN_CONF_CHANGED_CONFIG)
+		data->notify_dw = conf->enable_dw_notification;
+
+	return 0;
+}
+
 #ifdef CONFIG_MAC80211_DEBUGFS
 #define HWSIM_DEBUGFS_OPS					\
 	.link_add_debugfs = mac80211_hwsim_link_add_debugfs,
···
 	.get_et_strings = mac80211_hwsim_get_et_strings,	\
 	.start_pmsr = mac80211_hwsim_start_pmsr,		\
 	.abort_pmsr = mac80211_hwsim_abort_pmsr,		\
+	.start_nan = mac80211_hwsim_start_nan,                  \
+	.stop_nan = mac80211_hwsim_stop_nan,                    \
+	.nan_change_conf = mac80211_hwsim_change_nan_config,    \
 	HWSIM_DEBUGFS_OPS
 
 #define HWSIM_NON_MLO_OPS					\
···
 	u8 n_ciphers;
 	bool mlo;
 	const struct cfg80211_pmsr_capabilities *pmsr_capa;
+	bool nan_device;
 };
 
 static void hwsim_mcast_config_msg(struct sk_buff *mcast_skb,
···
 			return ret;
 	}
 
+	if (param->nan_device) {
+		ret = nla_put_flag(skb, HWSIM_ATTR_SUPPORT_NAN_DEVICE);
+		if (ret < 0)
+			return ret;
+	}
 	return 0;
 }
 
···
 		/* Why need here second address ? */
 		memcpy(data->addresses[1].addr, addr, ETH_ALEN);
 		data->addresses[1].addr[0] |= 0x40;
-		hw->wiphy->n_addresses = 2;
+		memcpy(data->addresses[2].addr, addr, ETH_ALEN);
+		data->addresses[2].addr[0] |= 0x50;
+
+		hw->wiphy->n_addresses = 3;
 		hw->wiphy->addresses = data->addresses;
 		/* possible address clash is checked at hash table insertion */
 	} else {
 		memcpy(data->addresses[0].addr, param->perm_addr, ETH_ALEN);
 		/* compatibility with automatically generated mac addr */
 		memcpy(data->addresses[1].addr, param->perm_addr, ETH_ALEN);
-		hw->wiphy->n_addresses = 2;
+		memcpy(data->addresses[2].addr, param->perm_addr, ETH_ALEN);
+		hw->wiphy->n_addresses = 3;
 		hw->wiphy->addresses = data->addresses;
 	}
 
···
 		data->if_limits[n_limits].types =
 						BIT(NL80211_IFTYPE_P2P_DEVICE);
 		n_limits++;
+	}
+
+	if (param->iftypes & BIT(NL80211_IFTYPE_NAN)) {
+		data->if_limits[n_limits].max = 1;
+		data->if_limits[n_limits].types = BIT(NL80211_IFTYPE_NAN);
+		n_limits++;
+
+		hw->wiphy->nan_supported_bands = BIT(NL80211_BAND_2GHZ) |
+						 BIT(NL80211_BAND_5GHZ);
+
+		hw->wiphy->nan_capa.flags = WIPHY_NAN_FLAGS_CONFIGURABLE_SYNC |
+					    WIPHY_NAN_FLAGS_USERSPACE_DE;
+		hw->wiphy->nan_capa.op_mode = NAN_OP_MODE_PHY_MODE_MASK |
+					      NAN_OP_MODE_80P80MHZ |
+					      NAN_OP_MODE_160MHZ;
+
+		hw->wiphy->nan_capa.n_antennas = 0x22;
+		hw->wiphy->nan_capa.max_channel_switch_time = 0;
+		hw->wiphy->nan_capa.dev_capabilities =
+			NAN_DEV_CAPA_EXT_KEY_ID_SUPPORTED |
+			NAN_DEV_CAPA_NDPE_SUPPORTED;
+
+		hrtimer_setup(&data->nan_timer, mac80211_hwsim_nan_dw_start,
+			      CLOCK_MONOTONIC, HRTIMER_MODE_ABS_SOFT);
 	}
 
 	data->if_combination.radar_detect_widths =
···
 					REGULATORY_STRICT_REG);
 	param.p2p_device = !!(data->hw->wiphy->interface_modes &
 					BIT(NL80211_IFTYPE_P2P_DEVICE));
+	param.nan_device = !!(data->hw->wiphy->interface_modes &
+					BIT(NL80211_IFTYPE_NAN));
 	param.use_chanctx = data->use_chanctx;
 	param.regd = data->regd;
 	param.channels = data->channels;
···
 
 	param.reg_strict = info->attrs[HWSIM_ATTR_REG_STRICT_REG];
 	param.p2p_device = info->attrs[HWSIM_ATTR_SUPPORT_P2P_DEVICE];
+	param.nan_device = info->attrs[HWSIM_ATTR_SUPPORT_NAN_DEVICE];
 	param.channels = channels;
 	param.destroy_on_close =
 		info->attrs[HWSIM_ATTR_DESTROY_RADIO_ON_CLOSE];
···
 	    param.iftypes & BIT(NL80211_IFTYPE_P2P_DEVICE)) {
 		param.iftypes |= BIT(NL80211_IFTYPE_P2P_DEVICE);
 		param.p2p_device = true;
+	}
+
+	/* ensure both flag and iftype support is honored */
+	if (param.nan_device ||
+	    param.iftypes & BIT(NL80211_IFTYPE_NAN)) {
+		param.iftypes |= BIT(NL80211_IFTYPE_NAN);
+		param.nan_device = true;
 	}
 
 	if (info->attrs[HWSIM_ATTR_CIPHER_SUPPORT]) {
···
 		}
 
 		param.p2p_device = support_p2p_device;
+		param.nan_device = true;
 		param.mlo = mlo;
 		param.multi_radio = multi_radio;
 		param.use_chanctx = channels > 1 || mlo || multi_radio;
 		param.iftypes = HWSIM_IFTYPE_SUPPORT_MASK;
 		if (param.p2p_device)
 			param.iftypes |= BIT(NL80211_IFTYPE_P2P_DEVICE);
+		param.iftypes |= BIT(NL80211_IFTYPE_NAN);
 
 		err = mac80211_hwsim_new_radio(NULL, &param);
 		if (err < 0)

drivers/net/wireless/virtual/mac80211_hwsim.h

···
  * mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
  * Copyright (c) 2008, Jouni Malinen <[e-mail]>
  * Copyright (c) 2011, Javier Lopez <[e-mail]>
- * Copyright (C) 2020, 2022-2024 Intel Corporation
+ * Copyright (C) 2020, 2022-2025 Intel Corporation
  */
 
 #ifndef __MAC80211_HWSIM_H
···
  * @HWSIM_ATTR_MULTI_RADIO: Register multiple wiphy radios (flag).
  *	Adds one radio for each band. Number of supported channels will be set for
  *	each radio instead of for the wiphy.
+ * @HWSIM_ATTR_SUPPORT_NAN_DEVICE: support NAN Device virtual interface (flag)
  * @__HWSIM_ATTR_MAX: enum limit
  */
 enum hwsim_attrs {
···
 	HWSIM_ATTR_PMSR_REQUEST,
 	HWSIM_ATTR_PMSR_RESULT,
 	HWSIM_ATTR_MULTI_RADIO,
+	HWSIM_ATTR_SUPPORT_NAN_DEVICE,
 	__HWSIM_ATTR_MAX,
 };
 #define HWSIM_ATTR_MAX (__HWSIM_ATTR_MAX - 1)