drivers/net/wireless/mac80211_hwsim.c - kernel/msm - Gitiles

 /*
  * mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
  * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 /*
  * TODO:
  * - IBSS mode simulation (Beacon transmission with competition for "air time")
  * - IEEE 802.11a and 802.11n modes
  * - RX filtering based on filter configuration (data->rx_filter)
  */

 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <net/mac80211.h>
 #include <net/ieee80211_radiotap.h>
 #include <linux/if_arp.h>
 #include <linux/rtnetlink.h>
 #include <linux/etherdevice.h>

 MODULE_AUTHOR("Jouni Malinen");
 MODULE_DESCRIPTION("Software simulator of 802.11 radio(s) for mac80211");
 MODULE_LICENSE("GPL");

 static int radios = 2;
 module_param(radios, int, 0444);
 MODULE_PARM_DESC(radios, "Number of simulated radios");

 struct hwsim_vif_priv {
 	u32 magic;
 };

 #define HWSIM_VIF_MAGIC	0x69537748

 static inline void hwsim_check_magic(struct ieee80211_vif *vif)
 {
 	struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
 	WARN_ON(vp->magic != HWSIM_VIF_MAGIC);
 }

 static inline void hwsim_set_magic(struct ieee80211_vif *vif)
 {
 	struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
 	vp->magic = HWSIM_VIF_MAGIC;
 }

 static inline void hwsim_clear_magic(struct ieee80211_vif *vif)
 {
 	struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
 	vp->magic = 0;
 }

 struct hwsim_sta_priv {
 	u32 magic;
 };

 #define HWSIM_STA_MAGIC	0x6d537748

 static inline void hwsim_check_sta_magic(struct ieee80211_sta *sta)
 {
 	struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
 	WARN_ON(sp->magic != HWSIM_VIF_MAGIC);
 }

 static inline void hwsim_set_sta_magic(struct ieee80211_sta *sta)
 {
 	struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
 	sp->magic = HWSIM_VIF_MAGIC;
 }

 static inline void hwsim_clear_sta_magic(struct ieee80211_sta *sta)
 {
 	struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
 	sp->magic = 0;
 }

 static struct class *hwsim_class;

 static struct net_device *hwsim_mon; /* global monitor netdev */


 static const struct ieee80211_channel hwsim_channels[] = {
 	{ .center_freq = 2412 },
 	{ .center_freq = 2417 },
 	{ .center_freq = 2422 },
 	{ .center_freq = 2427 },
 	{ .center_freq = 2432 },
 	{ .center_freq = 2437 },
 	{ .center_freq = 2442 },
 	{ .center_freq = 2447 },
 	{ .center_freq = 2452 },
 	{ .center_freq = 2457 },
 	{ .center_freq = 2462 },
 	{ .center_freq = 2467 },
 	{ .center_freq = 2472 },
 	{ .center_freq = 2484 },
 };

 static const struct ieee80211_rate hwsim_rates[] = {
 	{ .bitrate = 10 },
 	{ .bitrate = 20, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 	{ .bitrate = 55, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 	{ .bitrate = 110, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 	{ .bitrate = 60 },
 	{ .bitrate = 90 },
 	{ .bitrate = 120 },
 	{ .bitrate = 180 },
 	{ .bitrate = 240 },
 	{ .bitrate = 360 },
 	{ .bitrate = 480 },
 	{ .bitrate = 540 }
 };

 static spinlock_t hwsim_radio_lock;
 static struct list_head hwsim_radios;

 struct mac80211_hwsim_data {
 	struct list_head list;
 	struct ieee80211_hw *hw;
 	struct device *dev;
 	struct ieee80211_supported_band band;
 	struct ieee80211_channel channels[ARRAY_SIZE(hwsim_channels)];
 	struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];

 	struct ieee80211_channel *channel;
 	int radio_enabled;
 	unsigned long beacon_int; /* in jiffies unit */
 	unsigned int rx_filter;
 	int started;
 	struct timer_list beacon_timer;
 };


 struct hwsim_radiotap_hdr {
 	struct ieee80211_radiotap_header hdr;
 	u8 rt_flags;
 	u8 rt_rate;
 	__le16 rt_channel;
 	__le16 rt_chbitmask;
 } __attribute__ ((packed));


 static int hwsim_mon_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	/* TODO: allow packet injection */
 	dev_kfree_skb(skb);
 	return 0;
 }


 static void mac80211_hwsim_monitor_rx(struct ieee80211_hw *hw,
 				      struct sk_buff *tx_skb)
 {
 	struct mac80211_hwsim_data *data = hw->priv;
 	struct sk_buff *skb;
 	struct hwsim_radiotap_hdr *hdr;
 	u16 flags;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx_skb);
 	struct ieee80211_rate *txrate = ieee80211_get_tx_rate(hw, info);

 	if (!netif_running(hwsim_mon))
 		return;

 	skb = skb_copy_expand(tx_skb, sizeof(*hdr), 0, GFP_ATOMIC);
 	if (skb == NULL)
 		return;

 	hdr = (struct hwsim_radiotap_hdr *) skb_push(skb, sizeof(*hdr));
 	hdr->hdr.it_version = PKTHDR_RADIOTAP_VERSION;
 	hdr->hdr.it_pad = 0;
 	hdr->hdr.it_len = cpu_to_le16(sizeof(*hdr));
 	hdr->hdr.it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 					  (1 << IEEE80211_RADIOTAP_RATE) |
 					  (1 << IEEE80211_RADIOTAP_CHANNEL));
 	hdr->rt_flags = 0;
 	hdr->rt_rate = txrate->bitrate / 5;
 	hdr->rt_channel = cpu_to_le16(data->channel->center_freq);
 	flags = IEEE80211_CHAN_2GHZ;
 	if (txrate->flags & IEEE80211_RATE_ERP_G)
 		flags |= IEEE80211_CHAN_OFDM;
 	else
 		flags |= IEEE80211_CHAN_CCK;
 	hdr->rt_chbitmask = cpu_to_le16(flags);

 	skb->dev = hwsim_mon;
 	skb_set_mac_header(skb, 0);
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
 	skb->pkt_type = PACKET_OTHERHOST;
 	skb->protocol = htons(ETH_P_802_2);
 	memset(skb->cb, 0, sizeof(skb->cb));
 	netif_rx(skb);
 }


 static bool mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
 				    struct sk_buff *skb)
 {
 	struct mac80211_hwsim_data *data = hw->priv, *data2;
 	bool ack = false;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct ieee80211_rx_status rx_status;

 	memset(&rx_status, 0, sizeof(rx_status));
 	/* TODO: set mactime */
 	rx_status.freq = data->channel->center_freq;
 	rx_status.band = data->channel->band;
 	rx_status.rate_idx = info->tx_rate_idx;
 	/* TODO: simulate signal strength (and optional packet drop) */

 	/* Copy skb to all enabled radios that are on the current frequency */
 	spin_lock(&hwsim_radio_lock);
 	list_for_each_entry(data2, &hwsim_radios, list) {
 		struct sk_buff *nskb;

 		if (data == data2)
 			continue;

 		if (!data2->started || !data2->radio_enabled ||
 		    data->channel->center_freq != data2->channel->center_freq)
 			continue;

 		nskb = skb_copy(skb, GFP_ATOMIC);
 		if (nskb == NULL)
 			continue;

 		if (memcmp(hdr->addr1, data2->hw->wiphy->perm_addr,
 			   ETH_ALEN) == 0)
 			ack = true;
 		ieee80211_rx_irqsafe(data2->hw, nskb, &rx_status);
 	}
 	spin_unlock(&hwsim_radio_lock);

 	return ack;
 }


 static int mac80211_hwsim_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
 	struct mac80211_hwsim_data *data = hw->priv;
 	bool ack;
 	struct ieee80211_tx_info *txi;

 	mac80211_hwsim_monitor_rx(hw, skb);

 	if (skb->len < 10) {
 		/* Should not happen; just a sanity check for addr1 use */
 		dev_kfree_skb(skb);
 		return NETDEV_TX_OK;
 	}

 	if (!data->radio_enabled) {
 		printk(KERN_DEBUG "%s: dropped TX frame since radio "
 		       "disabled\n", wiphy_name(hw->wiphy));
 		dev_kfree_skb(skb);
 		return NETDEV_TX_OK;
 	}

 	ack = mac80211_hwsim_tx_frame(hw, skb);

 	txi = IEEE80211_SKB_CB(skb);

 	if (txi->control.vif)
 		hwsim_check_magic(txi->control.vif);
 	if (txi->control.sta)
 		hwsim_check_sta_magic(txi->control.sta);

 	memset(&txi->status, 0, sizeof(txi->status));
 	if (!(txi->flags & IEEE80211_TX_CTL_NO_ACK)) {
 		if (ack)
 			txi->flags |= IEEE80211_TX_STAT_ACK;
 		else
 			txi->status.excessive_retries = 1;
 	}
 	ieee80211_tx_status_irqsafe(hw, skb);
 	return NETDEV_TX_OK;
 }


 static int mac80211_hwsim_start(struct ieee80211_hw *hw)
 {
 	struct mac80211_hwsim_data *data = hw->priv;
 	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 	data->started = 1;
 	return 0;
 }


 static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
 {
 	struct mac80211_hwsim_data *data = hw->priv;
 	data->started = 0;
 	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 }


 static int mac80211_hwsim_add_interface(struct ieee80211_hw *hw,
 					struct ieee80211_if_init_conf *conf)
 {
 	DECLARE_MAC_BUF(mac);
 	printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 	       wiphy_name(hw->wiphy), __func__, conf->type,
 	       print_mac(mac, conf->mac_addr));
 	hwsim_set_magic(conf->vif);
 	return 0;
 }


 static void mac80211_hwsim_remove_interface(
 	struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf)
 {
 	DECLARE_MAC_BUF(mac);
 	printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 	       wiphy_name(hw->wiphy), __func__, conf->type,
 	       print_mac(mac, conf->mac_addr));
 	hwsim_check_magic(conf->vif);
 	hwsim_clear_magic(conf->vif);
 }


 static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
 				     struct ieee80211_vif *vif)
 {
 	struct ieee80211_hw *hw = arg;
 	struct sk_buff *skb;
 	struct ieee80211_tx_info *info;

 	hwsim_check_magic(vif);

 	if (vif->type != NL80211_IFTYPE_AP)
 		return;

 	skb = ieee80211_beacon_get(hw, vif);
 	if (skb == NULL)
 		return;
 	info = IEEE80211_SKB_CB(skb);

 	mac80211_hwsim_monitor_rx(hw, skb);
 	mac80211_hwsim_tx_frame(hw, skb);
 	dev_kfree_skb(skb);
 }


 static void mac80211_hwsim_beacon(unsigned long arg)
 {
 	struct ieee80211_hw *hw = (struct ieee80211_hw *) arg;
 	struct mac80211_hwsim_data *data = hw->priv;

 	if (!data->started || !data->radio_enabled)
 		return;

 	ieee80211_iterate_active_interfaces_atomic(
 		hw, mac80211_hwsim_beacon_tx, hw);

 	data->beacon_timer.expires = jiffies + data->beacon_int;
 	add_timer(&data->beacon_timer);
 }


 static int mac80211_hwsim_config(struct ieee80211_hw *hw,
 				 struct ieee80211_conf *conf)
 {
 	struct mac80211_hwsim_data *data = hw->priv;

 	printk(KERN_DEBUG "%s:%s (freq=%d radio_enabled=%d beacon_int=%d)\n",
 	       wiphy_name(hw->wiphy), __func__,
 	       conf->channel->center_freq, conf->radio_enabled,
 	       conf->beacon_int);

 	data->channel = conf->channel;
 	data->radio_enabled = conf->radio_enabled;
 	data->beacon_int = 1024 * conf->beacon_int / 1000 * HZ / 1000;
 	if (data->beacon_int < 1)
 		data->beacon_int = 1;

 	if (!data->started || !data->radio_enabled)
 		del_timer(&data->beacon_timer);
 	else
 		mod_timer(&data->beacon_timer, jiffies + data->beacon_int);

 	return 0;
 }


 static void mac80211_hwsim_configure_filter(struct ieee80211_hw *hw,
 					    unsigned int changed_flags,
 					    unsigned int *total_flags,
 					    int mc_count,
 					    struct dev_addr_list *mc_list)
 {
 	struct mac80211_hwsim_data *data = hw->priv;

 	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);

 	data->rx_filter = 0;
 	if (*total_flags & FIF_PROMISC_IN_BSS)
 		data->rx_filter |= FIF_PROMISC_IN_BSS;
 	if (*total_flags & FIF_ALLMULTI)
 		data->rx_filter |= FIF_ALLMULTI;

 	*total_flags = data->rx_filter;
 }

 static int mac80211_hwsim_config_interface(struct ieee80211_hw *hw,
 					   struct ieee80211_vif *vif,
 					   struct ieee80211_if_conf *conf)
 {
 	hwsim_check_magic(vif);
 	return 0;
 }

 static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw,
 					    struct ieee80211_vif *vif,
 					    struct ieee80211_bss_conf *info,
 					    u32 changed)
 {
 	hwsim_check_magic(vif);
 }

 static void mac80211_hwsim_sta_notify(struct ieee80211_hw *hw,
 				      struct ieee80211_vif *vif,
 				      enum sta_notify_cmd cmd,
 				      struct ieee80211_sta *sta)
 {
 	hwsim_check_magic(vif);
 	switch (cmd) {
 	case STA_NOTIFY_ADD:
 		hwsim_set_sta_magic(sta);
 		break;
 	case STA_NOTIFY_REMOVE:
 		hwsim_clear_sta_magic(sta);
 		break;
 	}
 }

 static int mac80211_hwsim_set_tim(struct ieee80211_hw *hw,
 				  struct ieee80211_sta *sta,
 				  bool set)
 {
 	hwsim_check_sta_magic(sta);
 	return 0;
 }

 static const struct ieee80211_ops mac80211_hwsim_ops =
 {
 	.tx = mac80211_hwsim_tx,
 	.start = mac80211_hwsim_start,
 	.stop = mac80211_hwsim_stop,
 	.add_interface = mac80211_hwsim_add_interface,
 	.remove_interface = mac80211_hwsim_remove_interface,
 	.config = mac80211_hwsim_config,
 	.configure_filter = mac80211_hwsim_configure_filter,
 	.config_interface = mac80211_hwsim_config_interface,
 	.bss_info_changed = mac80211_hwsim_bss_info_changed,
 	.sta_notify = mac80211_hwsim_sta_notify,
 	.set_tim = mac80211_hwsim_set_tim,
 };


 static void mac80211_hwsim_free(void)
 {
 	struct list_head tmplist, *i, *tmp;
 	struct mac80211_hwsim_data *data;

 	INIT_LIST_HEAD(&tmplist);

 	spin_lock_bh(&hwsim_radio_lock);
 	list_for_each_safe(i, tmp, &hwsim_radios)
 		list_move(i, &tmplist);
 	spin_unlock_bh(&hwsim_radio_lock);

 	list_for_each_entry(data, &tmplist, list) {
 		ieee80211_unregister_hw(data->hw);
 		device_unregister(data->dev);
 		ieee80211_free_hw(data->hw);
 	}
 	class_destroy(hwsim_class);
 }


 static struct device_driver mac80211_hwsim_driver = {
 	.name = "mac80211_hwsim"
 };


 static void hwsim_mon_setup(struct net_device *dev)
 {
 	dev->hard_start_xmit = hwsim_mon_xmit;
 	dev->destructor = free_netdev;
 	ether_setup(dev);
 	dev->tx_queue_len = 0;
 	dev->type = ARPHRD_IEEE80211_RADIOTAP;
 	memset(dev->dev_addr, 0, ETH_ALEN);
 	dev->dev_addr[0] = 0x12;
 }


 static int __init init_mac80211_hwsim(void)
 {
 	int i, err = 0;
 	u8 addr[ETH_ALEN];
 	struct mac80211_hwsim_data *data;
 	struct ieee80211_hw *hw;
 	DECLARE_MAC_BUF(mac);

 	if (radios < 1 || radios > 100)
 		return -EINVAL;

 	spin_lock_init(&hwsim_radio_lock);
 	INIT_LIST_HEAD(&hwsim_radios);

 	hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim");
 	if (IS_ERR(hwsim_class))
 		return PTR_ERR(hwsim_class);

 	memset(addr, 0, ETH_ALEN);
 	addr[0] = 0x02;

 	for (i = 0; i < radios; i++) {
 		printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n",
 		       i);
 		hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops);
 		if (!hw) {
 			printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw "
 			       "failed\n");
 			err = -ENOMEM;
 			goto failed;
 		}
 		data = hw->priv;
 		data->hw = hw;

 		data->dev = device_create(hwsim_class, NULL, 0, hw,
 					  "hwsim%d", i);
 		if (IS_ERR(data->dev)) {
 			printk(KERN_DEBUG
 			       "mac80211_hwsim: device_create "
 			       "failed (%ld)\n", PTR_ERR(data->dev));
 			err = -ENOMEM;
 			goto failed_drvdata;
 		}
 		data->dev->driver = &mac80211_hwsim_driver;

 		SET_IEEE80211_DEV(hw, data->dev);
 		addr[3] = i >> 8;
 		addr[4] = i;
 		SET_IEEE80211_PERM_ADDR(hw, addr);

 		hw->channel_change_time = 1;
 		hw->queues = 4;
 		hw->wiphy->interface_modes =
 			BIT(NL80211_IFTYPE_STATION) |
 			BIT(NL80211_IFTYPE_AP);
 		hw->ampdu_queues = 1;

 		/* ask mac80211 to reserve space for magic */
 		hw->vif_data_size = sizeof(struct hwsim_vif_priv);
 		hw->sta_data_size = sizeof(struct hwsim_sta_priv);

 		memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));
 		memcpy(data->rates, hwsim_rates, sizeof(hwsim_rates));
 		data->band.channels = data->channels;
 		data->band.n_channels = ARRAY_SIZE(hwsim_channels);
 		data->band.bitrates = data->rates;
 		data->band.n_bitrates = ARRAY_SIZE(hwsim_rates);
 		data->band.ht_info.ht_supported = 1;
 		data->band.ht_info.cap = IEEE80211_HT_CAP_SUP_WIDTH |
 			IEEE80211_HT_CAP_GRN_FLD |
 			IEEE80211_HT_CAP_SGI_40 |
 			IEEE80211_HT_CAP_DSSSCCK40;
 		data->band.ht_info.ampdu_factor = 0x3;
 		data->band.ht_info.ampdu_density = 0x6;
 		memset(data->band.ht_info.supp_mcs_set, 0,
 		       sizeof(data->band.ht_info.supp_mcs_set));
 		data->band.ht_info.supp_mcs_set[0] = 0xff;
 		data->band.ht_info.supp_mcs_set[1] = 0xff;
 		data->band.ht_info.supp_mcs_set[12] =
 			IEEE80211_HT_CAP_MCS_TX_DEFINED;
 		hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &data->band;

 		err = ieee80211_register_hw(hw);
 		if (err < 0) {
 			printk(KERN_DEBUG "mac80211_hwsim: "
 			       "ieee80211_register_hw failed (%d)\n", err);
 			goto failed_hw;
 		}

 		printk(KERN_DEBUG "%s: hwaddr %s registered\n",
 		       wiphy_name(hw->wiphy),
 		       print_mac(mac, hw->wiphy->perm_addr));

 		setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
 			    (unsigned long) hw);

 		list_add_tail(&data->list, &hwsim_radios);
 	}

 	hwsim_mon = alloc_netdev(0, "hwsim%d", hwsim_mon_setup);
 	if (hwsim_mon == NULL)
 		goto failed;

 	rtnl_lock();

 	err = dev_alloc_name(hwsim_mon, hwsim_mon->name);
 	if (err < 0)
 		goto failed_mon;


 	err = register_netdevice(hwsim_mon);
 	if (err < 0)
 		goto failed_mon;

 	rtnl_unlock();

 	return 0;

 failed_mon:
 	rtnl_unlock();
 	free_netdev(hwsim_mon);
 	mac80211_hwsim_free();
 	return err;

 failed_hw:
 	device_unregister(data->dev);
 failed_drvdata:
 	ieee80211_free_hw(hw);
 failed:
 	mac80211_hwsim_free();
 	return err;
 }


 static void __exit exit_mac80211_hwsim(void)
 {
 	printk(KERN_DEBUG "mac80211_hwsim: unregister radios\n");

 	unregister_netdev(hwsim_mon);
 	mac80211_hwsim_free();
 }


 module_init(init_mac80211_hwsim);
 module_exit(exit_mac80211_hwsim);
	/*
	* mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
	* Copyright (c) 2008, Jouni Malinen <j@w1.fi>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	/*
	* TODO:
	* - IBSS mode simulation (Beacon transmission with competition for "air time")
	* - IEEE 802.11a and 802.11n modes
	* - RX filtering based on filter configuration (data->rx_filter)
	*/

	#include <linux/list.h>
	#include <linux/spinlock.h>
	#include <net/mac80211.h>
	#include <net/ieee80211_radiotap.h>
	#include <linux/if_arp.h>
	#include <linux/rtnetlink.h>
	#include <linux/etherdevice.h>

	MODULE_AUTHOR("Jouni Malinen");
	MODULE_DESCRIPTION("Software simulator of 802.11 radio(s) for mac80211");
	MODULE_LICENSE("GPL");

	static int radios = 2;
	module_param(radios, int, 0444);
	MODULE_PARM_DESC(radios, "Number of simulated radios");

	struct hwsim_vif_priv {
	u32 magic;
	};

	#define HWSIM_VIF_MAGIC 0x69537748

	static inline void hwsim_check_magic(struct ieee80211_vif *vif)
	{
	struct hwsim_vif_priv vp = (void )vif->drv_priv;
	WARN_ON(vp->magic != HWSIM_VIF_MAGIC);
	}

	static inline void hwsim_set_magic(struct ieee80211_vif *vif)
	{
	struct hwsim_vif_priv vp = (void )vif->drv_priv;
	vp->magic = HWSIM_VIF_MAGIC;
	}

	static inline void hwsim_clear_magic(struct ieee80211_vif *vif)
	{
	struct hwsim_vif_priv vp = (void )vif->drv_priv;
	vp->magic = 0;
	}

	struct hwsim_sta_priv {
	u32 magic;
	};

	#define HWSIM_STA_MAGIC 0x6d537748

	static inline void hwsim_check_sta_magic(struct ieee80211_sta *sta)
	{
	struct hwsim_sta_priv sp = (void )sta->drv_priv;
	WARN_ON(sp->magic != HWSIM_VIF_MAGIC);
	}

	static inline void hwsim_set_sta_magic(struct ieee80211_sta *sta)
	{
	struct hwsim_sta_priv sp = (void )sta->drv_priv;
	sp->magic = HWSIM_VIF_MAGIC;
	}

	static inline void hwsim_clear_sta_magic(struct ieee80211_sta *sta)
	{
	struct hwsim_sta_priv sp = (void )sta->drv_priv;
	sp->magic = 0;
	}

	static struct class *hwsim_class;

	static struct net_device hwsim_mon; / global monitor netdev */


	static const struct ieee80211_channel hwsim_channels[] = {
	{ .center_freq = 2412 },
	{ .center_freq = 2417 },
	{ .center_freq = 2422 },
	{ .center_freq = 2427 },
	{ .center_freq = 2432 },
	{ .center_freq = 2437 },
	{ .center_freq = 2442 },
	{ .center_freq = 2447 },
	{ .center_freq = 2452 },
	{ .center_freq = 2457 },
	{ .center_freq = 2462 },
	{ .center_freq = 2467 },
	{ .center_freq = 2472 },
	{ .center_freq = 2484 },
	};

	static const struct ieee80211_rate hwsim_rates[] = {
	{ .bitrate = 10 },
	{ .bitrate = 20, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 55, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 110, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
	{ .bitrate = 60 },
	{ .bitrate = 90 },
	{ .bitrate = 120 },
	{ .bitrate = 180 },
	{ .bitrate = 240 },
	{ .bitrate = 360 },
	{ .bitrate = 480 },
	{ .bitrate = 540 }
	};

	static spinlock_t hwsim_radio_lock;
	static struct list_head hwsim_radios;

	struct mac80211_hwsim_data {
	struct list_head list;
	struct ieee80211_hw *hw;
	struct device *dev;
	struct ieee80211_supported_band band;
	struct ieee80211_channel channels[ARRAY_SIZE(hwsim_channels)];
	struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];

	struct ieee80211_channel *channel;
	int radio_enabled;
	unsigned long beacon_int; /* in jiffies unit */
	unsigned int rx_filter;
	int started;
	struct timer_list beacon_timer;
	};


	struct hwsim_radiotap_hdr {
	struct ieee80211_radiotap_header hdr;
	u8 rt_flags;
	u8 rt_rate;
	__le16 rt_channel;
	__le16 rt_chbitmask;
	} __attribute__ ((packed));


	static int hwsim_mon_xmit(struct sk_buff skb, struct net_device dev)
	{
	/* TODO: allow packet injection */
	dev_kfree_skb(skb);
	return 0;
	}


	static void mac80211_hwsim_monitor_rx(struct ieee80211_hw *hw,
	struct sk_buff *tx_skb)
	{
	struct mac80211_hwsim_data *data = hw->priv;
	struct sk_buff *skb;
	struct hwsim_radiotap_hdr *hdr;
	u16 flags;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx_skb);
	struct ieee80211_rate *txrate = ieee80211_get_tx_rate(hw, info);

	if (!netif_running(hwsim_mon))
	return;

	skb = skb_copy_expand(tx_skb, sizeof(*hdr), 0, GFP_ATOMIC);
	if (skb == NULL)
	return;

	hdr = (struct hwsim_radiotap_hdr ) skb_push(skb, sizeof(hdr));
	hdr->hdr.it_version = PKTHDR_RADIOTAP_VERSION;
	hdr->hdr.it_pad = 0;
	hdr->hdr.it_len = cpu_to_le16(sizeof(*hdr));
	hdr->hdr.it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) \|
	(1 << IEEE80211_RADIOTAP_RATE) \|
	(1 << IEEE80211_RADIOTAP_CHANNEL));
	hdr->rt_flags = 0;
	hdr->rt_rate = txrate->bitrate / 5;
	hdr->rt_channel = cpu_to_le16(data->channel->center_freq);
	flags = IEEE80211_CHAN_2GHZ;
	if (txrate->flags & IEEE80211_RATE_ERP_G)
	flags \|= IEEE80211_CHAN_OFDM;
	else
	flags \|= IEEE80211_CHAN_CCK;
	hdr->rt_chbitmask = cpu_to_le16(flags);

	skb->dev = hwsim_mon;
	skb_set_mac_header(skb, 0);
	skb->ip_summed = CHECKSUM_UNNECESSARY;
	skb->pkt_type = PACKET_OTHERHOST;
	skb->protocol = htons(ETH_P_802_2);
	memset(skb->cb, 0, sizeof(skb->cb));
	netif_rx(skb);
	}


	static bool mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
	struct sk_buff *skb)
	{
	struct mac80211_hwsim_data data = hw->priv, data2;
	bool ack = false;
	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct ieee80211_rx_status rx_status;

	memset(&rx_status, 0, sizeof(rx_status));
	/* TODO: set mactime */
	rx_status.freq = data->channel->center_freq;
	rx_status.band = data->channel->band;
	rx_status.rate_idx = info->tx_rate_idx;
	/* TODO: simulate signal strength (and optional packet drop) */

	/* Copy skb to all enabled radios that are on the current frequency */
	spin_lock(&hwsim_radio_lock);
	list_for_each_entry(data2, &hwsim_radios, list) {
	struct sk_buff *nskb;

	if (data == data2)
	continue;

	if (!data2->started \|\| !data2->radio_enabled \|\|
	data->channel->center_freq != data2->channel->center_freq)
	continue;

	nskb = skb_copy(skb, GFP_ATOMIC);
	if (nskb == NULL)
	continue;

	if (memcmp(hdr->addr1, data2->hw->wiphy->perm_addr,
	ETH_ALEN) == 0)
	ack = true;
	ieee80211_rx_irqsafe(data2->hw, nskb, &rx_status);
	}
	spin_unlock(&hwsim_radio_lock);

	return ack;
	}


	static int mac80211_hwsim_tx(struct ieee80211_hw hw, struct sk_buff skb)
	{
	struct mac80211_hwsim_data *data = hw->priv;
	bool ack;
	struct ieee80211_tx_info *txi;

	mac80211_hwsim_monitor_rx(hw, skb);

	if (skb->len < 10) {
	/* Should not happen; just a sanity check for addr1 use */
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
	}

	if (!data->radio_enabled) {
	printk(KERN_DEBUG "%s: dropped TX frame since radio "
	"disabled\n", wiphy_name(hw->wiphy));
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
	}

	ack = mac80211_hwsim_tx_frame(hw, skb);

	txi = IEEE80211_SKB_CB(skb);

	if (txi->control.vif)
	hwsim_check_magic(txi->control.vif);
	if (txi->control.sta)
	hwsim_check_sta_magic(txi->control.sta);

	memset(&txi->status, 0, sizeof(txi->status));
	if (!(txi->flags & IEEE80211_TX_CTL_NO_ACK)) {
	if (ack)
	txi->flags \|= IEEE80211_TX_STAT_ACK;
	else
	txi->status.excessive_retries = 1;
	}
	ieee80211_tx_status_irqsafe(hw, skb);
	return NETDEV_TX_OK;
	}


	static int mac80211_hwsim_start(struct ieee80211_hw *hw)
	{
	struct mac80211_hwsim_data *data = hw->priv;
	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
	data->started = 1;
	return 0;
	}


	static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
	{
	struct mac80211_hwsim_data *data = hw->priv;
	data->started = 0;
	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
	}


	static int mac80211_hwsim_add_interface(struct ieee80211_hw *hw,
	struct ieee80211_if_init_conf *conf)
	{
	DECLARE_MAC_BUF(mac);
	printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
	wiphy_name(hw->wiphy), __func__, conf->type,
	print_mac(mac, conf->mac_addr));
	hwsim_set_magic(conf->vif);
	return 0;
	}


	static void mac80211_hwsim_remove_interface(
	struct ieee80211_hw hw, struct ieee80211_if_init_conf conf)
	{
	DECLARE_MAC_BUF(mac);
	printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
	wiphy_name(hw->wiphy), __func__, conf->type,
	print_mac(mac, conf->mac_addr));
	hwsim_check_magic(conf->vif);
	hwsim_clear_magic(conf->vif);
	}


	static void mac80211_hwsim_beacon_tx(void arg, u8 mac,
	struct ieee80211_vif *vif)
	{
	struct ieee80211_hw *hw = arg;
	struct sk_buff *skb;
	struct ieee80211_tx_info *info;

	hwsim_check_magic(vif);

	if (vif->type != NL80211_IFTYPE_AP)
	return;

	skb = ieee80211_beacon_get(hw, vif);
	if (skb == NULL)
	return;
	info = IEEE80211_SKB_CB(skb);

	mac80211_hwsim_monitor_rx(hw, skb);
	mac80211_hwsim_tx_frame(hw, skb);
	dev_kfree_skb(skb);
	}


	static void mac80211_hwsim_beacon(unsigned long arg)
	{
	struct ieee80211_hw hw = (struct ieee80211_hw ) arg;
	struct mac80211_hwsim_data *data = hw->priv;

	if (!data->started \|\| !data->radio_enabled)
	return;

	ieee80211_iterate_active_interfaces_atomic(
	hw, mac80211_hwsim_beacon_tx, hw);

	data->beacon_timer.expires = jiffies + data->beacon_int;
	add_timer(&data->beacon_timer);
	}


	static int mac80211_hwsim_config(struct ieee80211_hw *hw,
	struct ieee80211_conf *conf)
	{
	struct mac80211_hwsim_data *data = hw->priv;

	printk(KERN_DEBUG "%s:%s (freq=%d radio_enabled=%d beacon_int=%d)\n",
	wiphy_name(hw->wiphy), __func__,
	conf->channel->center_freq, conf->radio_enabled,
	conf->beacon_int);

	data->channel = conf->channel;
	data->radio_enabled = conf->radio_enabled;
	data->beacon_int = 1024 * conf->beacon_int / 1000 * HZ / 1000;
	if (data->beacon_int < 1)
	data->beacon_int = 1;

	if (!data->started \|\| !data->radio_enabled)
	del_timer(&data->beacon_timer);
	else
	mod_timer(&data->beacon_timer, jiffies + data->beacon_int);

	return 0;
	}


	static void mac80211_hwsim_configure_filter(struct ieee80211_hw *hw,
	unsigned int changed_flags,
	unsigned int *total_flags,
	int mc_count,
	struct dev_addr_list *mc_list)
	{
	struct mac80211_hwsim_data *data = hw->priv;

	printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);

	data->rx_filter = 0;
	if (*total_flags & FIF_PROMISC_IN_BSS)
	data->rx_filter \|= FIF_PROMISC_IN_BSS;
	if (*total_flags & FIF_ALLMULTI)
	data->rx_filter \|= FIF_ALLMULTI;

	*total_flags = data->rx_filter;
	}

	static int mac80211_hwsim_config_interface(struct ieee80211_hw *hw,
	struct ieee80211_vif *vif,
	struct ieee80211_if_conf *conf)
	{
	hwsim_check_magic(vif);
	return 0;
	}

	static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw,
	struct ieee80211_vif *vif,
	struct ieee80211_bss_conf *info,
	u32 changed)
	{
	hwsim_check_magic(vif);
	}

	static void mac80211_hwsim_sta_notify(struct ieee80211_hw *hw,
	struct ieee80211_vif *vif,
	enum sta_notify_cmd cmd,
	struct ieee80211_sta *sta)
	{
	hwsim_check_magic(vif);
	switch (cmd) {
	case STA_NOTIFY_ADD:
	hwsim_set_sta_magic(sta);
	break;
	case STA_NOTIFY_REMOVE:
	hwsim_clear_sta_magic(sta);
	break;
	}
	}

	static int mac80211_hwsim_set_tim(struct ieee80211_hw *hw,
	struct ieee80211_sta *sta,
	bool set)
	{
	hwsim_check_sta_magic(sta);
	return 0;
	}

	static const struct ieee80211_ops mac80211_hwsim_ops =
	{
	.tx = mac80211_hwsim_tx,
	.start = mac80211_hwsim_start,
	.stop = mac80211_hwsim_stop,
	.add_interface = mac80211_hwsim_add_interface,
	.remove_interface = mac80211_hwsim_remove_interface,
	.config = mac80211_hwsim_config,
	.configure_filter = mac80211_hwsim_configure_filter,
	.config_interface = mac80211_hwsim_config_interface,
	.bss_info_changed = mac80211_hwsim_bss_info_changed,
	.sta_notify = mac80211_hwsim_sta_notify,
	.set_tim = mac80211_hwsim_set_tim,
	};


	static void mac80211_hwsim_free(void)
	{
	struct list_head tmplist, i, tmp;
	struct mac80211_hwsim_data *data;

	INIT_LIST_HEAD(&tmplist);

	spin_lock_bh(&hwsim_radio_lock);
	list_for_each_safe(i, tmp, &hwsim_radios)
	list_move(i, &tmplist);
	spin_unlock_bh(&hwsim_radio_lock);

	list_for_each_entry(data, &tmplist, list) {
	ieee80211_unregister_hw(data->hw);
	device_unregister(data->dev);
	ieee80211_free_hw(data->hw);
	}
	class_destroy(hwsim_class);
	}


	static struct device_driver mac80211_hwsim_driver = {
	.name = "mac80211_hwsim"
	};


	static void hwsim_mon_setup(struct net_device *dev)
	{
	dev->hard_start_xmit = hwsim_mon_xmit;
	dev->destructor = free_netdev;
	ether_setup(dev);
	dev->tx_queue_len = 0;
	dev->type = ARPHRD_IEEE80211_RADIOTAP;
	memset(dev->dev_addr, 0, ETH_ALEN);
	dev->dev_addr[0] = 0x12;
	}


	static int __init init_mac80211_hwsim(void)
	{
	int i, err = 0;
	u8 addr[ETH_ALEN];
	struct mac80211_hwsim_data *data;
	struct ieee80211_hw *hw;
	DECLARE_MAC_BUF(mac);

	if (radios < 1 \|\| radios > 100)
	return -EINVAL;

	spin_lock_init(&hwsim_radio_lock);
	INIT_LIST_HEAD(&hwsim_radios);

	hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim");
	if (IS_ERR(hwsim_class))
	return PTR_ERR(hwsim_class);

	memset(addr, 0, ETH_ALEN);
	addr[0] = 0x02;

	for (i = 0; i < radios; i++) {
	printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n",
	i);
	hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops);
	if (!hw) {
	printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw "
	"failed\n");
	err = -ENOMEM;
	goto failed;
	}
	data = hw->priv;
	data->hw = hw;

	data->dev = device_create(hwsim_class, NULL, 0, hw,
	"hwsim%d", i);
	if (IS_ERR(data->dev)) {
	printk(KERN_DEBUG
	"mac80211_hwsim: device_create "
	"failed (%ld)\n", PTR_ERR(data->dev));
	err = -ENOMEM;
	goto failed_drvdata;
	}
	data->dev->driver = &mac80211_hwsim_driver;

	SET_IEEE80211_DEV(hw, data->dev);
	addr[3] = i >> 8;
	addr[4] = i;
	SET_IEEE80211_PERM_ADDR(hw, addr);

	hw->channel_change_time = 1;
	hw->queues = 4;
	hw->wiphy->interface_modes =
	BIT(NL80211_IFTYPE_STATION) \|
	BIT(NL80211_IFTYPE_AP);
	hw->ampdu_queues = 1;

	/* ask mac80211 to reserve space for magic */
	hw->vif_data_size = sizeof(struct hwsim_vif_priv);
	hw->sta_data_size = sizeof(struct hwsim_sta_priv);

	memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));
	memcpy(data->rates, hwsim_rates, sizeof(hwsim_rates));
	data->band.channels = data->channels;
	data->band.n_channels = ARRAY_SIZE(hwsim_channels);
	data->band.bitrates = data->rates;
	data->band.n_bitrates = ARRAY_SIZE(hwsim_rates);
	data->band.ht_info.ht_supported = 1;
	data->band.ht_info.cap = IEEE80211_HT_CAP_SUP_WIDTH \|
	IEEE80211_HT_CAP_GRN_FLD \|
	IEEE80211_HT_CAP_SGI_40 \|
	IEEE80211_HT_CAP_DSSSCCK40;
	data->band.ht_info.ampdu_factor = 0x3;
	data->band.ht_info.ampdu_density = 0x6;
	memset(data->band.ht_info.supp_mcs_set, 0,
	sizeof(data->band.ht_info.supp_mcs_set));
	data->band.ht_info.supp_mcs_set[0] = 0xff;
	data->band.ht_info.supp_mcs_set[1] = 0xff;
	data->band.ht_info.supp_mcs_set[12] =
	IEEE80211_HT_CAP_MCS_TX_DEFINED;
	hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &data->band;

	err = ieee80211_register_hw(hw);
	if (err < 0) {
	printk(KERN_DEBUG "mac80211_hwsim: "
	"ieee80211_register_hw failed (%d)\n", err);
	goto failed_hw;
	}

	printk(KERN_DEBUG "%s: hwaddr %s registered\n",
	wiphy_name(hw->wiphy),
	print_mac(mac, hw->wiphy->perm_addr));

	setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
	(unsigned long) hw);

	list_add_tail(&data->list, &hwsim_radios);
	}

	hwsim_mon = alloc_netdev(0, "hwsim%d", hwsim_mon_setup);
	if (hwsim_mon == NULL)
	goto failed;

	rtnl_lock();

	err = dev_alloc_name(hwsim_mon, hwsim_mon->name);
	if (err < 0)
	goto failed_mon;


	err = register_netdevice(hwsim_mon);
	if (err < 0)
	goto failed_mon;

	rtnl_unlock();

	return 0;

	failed_mon:
	rtnl_unlock();
	free_netdev(hwsim_mon);
	mac80211_hwsim_free();
	return err;

	failed_hw:
	device_unregister(data->dev);
	failed_drvdata:
	ieee80211_free_hw(hw);
	failed:
	mac80211_hwsim_free();
	return err;
	}


	static void __exit exit_mac80211_hwsim(void)
	{
	printk(KERN_DEBUG "mac80211_hwsim: unregister radios\n");

	unregister_netdev(hwsim_mon);
	mac80211_hwsim_free();
	}


	module_init(init_mac80211_hwsim);
	module_exit(exit_mac80211_hwsim);