drivers/net/wireless/mac80211_hwsim.c

   1 /*
   2  * mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
   3  * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 /*
  11  * TODO:
  12  * - IBSS mode simulation (Beacon transmission with competition for "air time")
  13  * - IEEE 802.11a and 802.11n modes
  14  * - RX filtering based on filter configuration (data->rx_filter)
  15  */
  16
  17 #include <net/mac80211.h>
  18 #include <net/ieee80211_radiotap.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/rtnetlink.h>
  21 #include <linux/etherdevice.h>
  22
  23 MODULE_AUTHOR("Jouni Malinen");
  24 MODULE_DESCRIPTION("Software simulator of 802.11 radio(s) for mac80211");
  25 MODULE_LICENSE("GPL");
  26
  27 static int radios = 2;
  28 module_param(radios, int, 0444);
  29 MODULE_PARM_DESC(radios, "Number of simulated radios");
  30
  31 struct hwsim_vif_priv {
  32         u32 magic;
  33 };
  34
  35 #define HWSIM_VIF_MAGIC 0x69537748
  36
  37 static inline void hwsim_check_magic(struct ieee80211_vif *vif)
  38 {
  39         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  40         WARN_ON(vp->magic != HWSIM_VIF_MAGIC);
  41 }
  42
  43 static inline void hwsim_set_magic(struct ieee80211_vif *vif)
  44 {
  45         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  46         vp->magic = HWSIM_VIF_MAGIC;
  47 }
  48
  49 static inline void hwsim_clear_magic(struct ieee80211_vif *vif)
  50 {
  51         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  52         vp->magic = 0;
  53 }
  54
  55 static struct class *hwsim_class;
  56
  57 static struct ieee80211_hw **hwsim_radios;
  58 static int hwsim_radio_count;
  59 static struct net_device *hwsim_mon; /* global monitor netdev */
  60
  61
  62 static const struct ieee80211_channel hwsim_channels[] = {
  63         { .center_freq = 2412 },
  64         { .center_freq = 2417 },
  65         { .center_freq = 2422 },
  66         { .center_freq = 2427 },
  67         { .center_freq = 2432 },
  68         { .center_freq = 2437 },
  69         { .center_freq = 2442 },
  70         { .center_freq = 2447 },
  71         { .center_freq = 2452 },
  72         { .center_freq = 2457 },
  73         { .center_freq = 2462 },
  74         { .center_freq = 2467 },
  75         { .center_freq = 2472 },
  76         { .center_freq = 2484 },
  77 };
  78
  79 static const struct ieee80211_rate hwsim_rates[] = {
  80         { .bitrate = 10 },
  81         { .bitrate = 20, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  82         { .bitrate = 55, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  83         { .bitrate = 110, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  84         { .bitrate = 60 },
  85         { .bitrate = 90 },
  86         { .bitrate = 120 },
  87         { .bitrate = 180 },
  88         { .bitrate = 240 },
  89         { .bitrate = 360 },
  90         { .bitrate = 480 },
  91         { .bitrate = 540 }
  92 };
  93
  94 struct mac80211_hwsim_data {
  95         struct device *dev;
  96         struct ieee80211_supported_band band;
  97         struct ieee80211_channel channels[ARRAY_SIZE(hwsim_channels)];
  98         struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];
  99
 100         struct ieee80211_channel *channel;
 101         int radio_enabled;
 102         unsigned long beacon_int; /* in jiffies unit */
 103         unsigned int rx_filter;
 104         int started;
 105         struct timer_list beacon_timer;
 106 };
 107
 108
 109 struct hwsim_radiotap_hdr {
 110         struct ieee80211_radiotap_header hdr;
 111         u8 rt_flags;
 112         u8 rt_rate;
 113         __le16 rt_channel;
 114         __le16 rt_chbitmask;
 115 } __attribute__ ((packed));
 116
 117
 118 static int hwsim_mon_xmit(struct sk_buff *skb, struct net_device *dev)
 119 {
 120         /* TODO: allow packet injection */
 121         dev_kfree_skb(skb);
 122         return 0;
 123 }
 124
 125
 126 static void mac80211_hwsim_monitor_rx(struct ieee80211_hw *hw,
 127                                       struct sk_buff *tx_skb)
 128 {
 129         struct mac80211_hwsim_data *data = hw->priv;
 130         struct sk_buff *skb;
 131         struct hwsim_radiotap_hdr *hdr;
 132         u16 flags;
 133         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx_skb);
 134         struct ieee80211_rate *txrate = ieee80211_get_tx_rate(hw, info);
 135
 136         if (!netif_running(hwsim_mon))
 137                 return;
 138
 139         skb = skb_copy_expand(tx_skb, sizeof(*hdr), 0, GFP_ATOMIC);
 140         if (skb == NULL)
 141                 return;
 142
 143         hdr = (struct hwsim_radiotap_hdr *) skb_push(skb, sizeof(*hdr));
 144         hdr->hdr.it_version = PKTHDR_RADIOTAP_VERSION;
 145         hdr->hdr.it_pad = 0;
 146         hdr->hdr.it_len = cpu_to_le16(sizeof(*hdr));
 147         hdr->hdr.it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 148                                           (1 << IEEE80211_RADIOTAP_RATE) |
 149                                           (1 << IEEE80211_RADIOTAP_CHANNEL));
 150         hdr->rt_flags = 0;
 151         hdr->rt_rate = txrate->bitrate / 5;
 152         hdr->rt_channel = cpu_to_le16(data->channel->center_freq);
 153         flags = IEEE80211_CHAN_2GHZ;
 154         if (txrate->flags & IEEE80211_RATE_ERP_G)
 155                 flags |= IEEE80211_CHAN_OFDM;
 156         else
 157                 flags |= IEEE80211_CHAN_CCK;
 158         hdr->rt_chbitmask = cpu_to_le16(flags);
 159
 160         skb->dev = hwsim_mon;
 161         skb_set_mac_header(skb, 0);
 162         skb->ip_summed = CHECKSUM_UNNECESSARY;
 163         skb->pkt_type = PACKET_OTHERHOST;
 164         skb->protocol = htons(ETH_P_802_2);
 165         memset(skb->cb, 0, sizeof(skb->cb));
 166         netif_rx(skb);
 167 }
 168
 169
 170 static int mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
 171                                    struct sk_buff *skb)
 172 {
 173         struct mac80211_hwsim_data *data = hw->priv;
 174         int i, ack = 0;
 175         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 176         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 177         struct ieee80211_rx_status rx_status;
 178
 179         memset(&rx_status, 0, sizeof(rx_status));
 180         /* TODO: set mactime */
 181         rx_status.freq = data->channel->center_freq;
 182         rx_status.band = data->channel->band;
 183         rx_status.rate_idx = info->tx_rate_idx;
 184         /* TODO: simulate signal strength (and optional packet drop) */
 185
 186         /* Copy skb to all enabled radios that are on the current frequency */
 187         for (i = 0; i < hwsim_radio_count; i++) {
 188                 struct mac80211_hwsim_data *data2;
 189                 struct sk_buff *nskb;
 190
 191                 if (hwsim_radios[i] == NULL || hwsim_radios[i] == hw)
 192                         continue;
 193                 data2 = hwsim_radios[i]->priv;
 194                 if (!data2->started || !data2->radio_enabled ||
 195                     data->channel->center_freq != data2->channel->center_freq)
 196                         continue;
 197
 198                 nskb = skb_copy(skb, GFP_ATOMIC);
 199                 if (nskb == NULL)
 200                         continue;
 201
 202                 if (memcmp(hdr->addr1, hwsim_radios[i]->wiphy->perm_addr,
 203                            ETH_ALEN) == 0)
 204                         ack = 1;
 205                 ieee80211_rx_irqsafe(hwsim_radios[i], nskb, &rx_status);
 206         }
 207
 208         return ack;
 209 }
 210
 211
 212 static int mac80211_hwsim_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 213 {
 214         struct mac80211_hwsim_data *data = hw->priv;
 215         int ack;
 216         struct ieee80211_tx_info *txi;
 217
 218         mac80211_hwsim_monitor_rx(hw, skb);
 219
 220         if (skb->len < 10) {
 221                 /* Should not happen; just a sanity check for addr1 use */
 222                 dev_kfree_skb(skb);
 223                 return NETDEV_TX_OK;
 224         }
 225
 226         if (!data->radio_enabled) {
 227                 printk(KERN_DEBUG "%s: dropped TX frame since radio "
 228                        "disabled\n", wiphy_name(hw->wiphy));
 229                 dev_kfree_skb(skb);
 230                 return NETDEV_TX_OK;
 231         }
 232
 233         ack = mac80211_hwsim_tx_frame(hw, skb);
 234
 235         txi = IEEE80211_SKB_CB(skb);
 236
 237         hwsim_check_magic(txi->control.vif);
 238
 239         memset(&txi->status, 0, sizeof(txi->status));
 240         if (!(txi->flags & IEEE80211_TX_CTL_NO_ACK)) {
 241                 if (ack)
 242                         txi->flags |= IEEE80211_TX_STAT_ACK;
 243                 else
 244                         txi->status.excessive_retries = 1;
 245         }
 246         ieee80211_tx_status_irqsafe(hw, skb);
 247         return NETDEV_TX_OK;
 248 }
 249
 250
 251 static int mac80211_hwsim_start(struct ieee80211_hw *hw)
 252 {
 253         struct mac80211_hwsim_data *data = hw->priv;
 254         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 255         data->started = 1;
 256         return 0;
 257 }
 258
 259
 260 static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
 261 {
 262         struct mac80211_hwsim_data *data = hw->priv;
 263         data->started = 0;
 264         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 265 }
 266
 267
 268 static int mac80211_hwsim_add_interface(struct ieee80211_hw *hw,
 269                                         struct ieee80211_if_init_conf *conf)
 270 {
 271         DECLARE_MAC_BUF(mac);
 272         printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 273                wiphy_name(hw->wiphy), __func__, conf->type,
 274                print_mac(mac, conf->mac_addr));
 275         hwsim_set_magic(conf->vif);
 276         return 0;
 277 }
 278
 279
 280 static void mac80211_hwsim_remove_interface(
 281         struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf)
 282 {
 283         DECLARE_MAC_BUF(mac);
 284         printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 285                wiphy_name(hw->wiphy), __func__, conf->type,
 286                print_mac(mac, conf->mac_addr));
 287         hwsim_check_magic(conf->vif);
 288         hwsim_clear_magic(conf->vif);
 289 }
 290
 291
 292 static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
 293                                      struct ieee80211_vif *vif)
 294 {
 295         struct ieee80211_hw *hw = arg;
 296         struct sk_buff *skb;
 297         struct ieee80211_tx_info *info;
 298
 299         hwsim_check_magic(vif);
 300
 301         if (vif->type != NL80211_IFTYPE_AP)
 302                 return;
 303
 304         skb = ieee80211_beacon_get(hw, vif);
 305         if (skb == NULL)
 306                 return;
 307         info = IEEE80211_SKB_CB(skb);
 308
 309         mac80211_hwsim_monitor_rx(hw, skb);
 310         mac80211_hwsim_tx_frame(hw, skb);
 311         dev_kfree_skb(skb);
 312 }
 313
 314
 315 static void mac80211_hwsim_beacon(unsigned long arg)
 316 {
 317         struct ieee80211_hw *hw = (struct ieee80211_hw *) arg;
 318         struct mac80211_hwsim_data *data = hw->priv;
 319
 320         if (!data->started || !data->radio_enabled)
 321                 return;
 322
 323         ieee80211_iterate_active_interfaces_atomic(
 324                 hw, mac80211_hwsim_beacon_tx, hw);
 325
 326         data->beacon_timer.expires = jiffies + data->beacon_int;
 327         add_timer(&data->beacon_timer);
 328 }
 329
 330
 331 static int mac80211_hwsim_config(struct ieee80211_hw *hw,
 332                                  struct ieee80211_conf *conf)
 333 {
 334         struct mac80211_hwsim_data *data = hw->priv;
 335
 336         printk(KERN_DEBUG "%s:%s (freq=%d radio_enabled=%d beacon_int=%d)\n",
 337                wiphy_name(hw->wiphy), __func__,
 338                conf->channel->center_freq, conf->radio_enabled,
 339                conf->beacon_int);
 340
 341         data->channel = conf->channel;
 342         data->radio_enabled = conf->radio_enabled;
 343         data->beacon_int = 1024 * conf->beacon_int / 1000 * HZ / 1000;
 344         if (data->beacon_int < 1)
 345                 data->beacon_int = 1;
 346
 347         if (!data->started || !data->radio_enabled)
 348                 del_timer(&data->beacon_timer);
 349         else
 350                 mod_timer(&data->beacon_timer, jiffies + data->beacon_int);
 351
 352         return 0;
 353 }
 354
 355
 356 static void mac80211_hwsim_configure_filter(struct ieee80211_hw *hw,
 357                                             unsigned int changed_flags,
 358                                             unsigned int *total_flags,
 359                                             int mc_count,
 360                                             struct dev_addr_list *mc_list)
 361 {
 362         struct mac80211_hwsim_data *data = hw->priv;
 363
 364         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 365
 366         data->rx_filter = 0;
 367         if (*total_flags & FIF_PROMISC_IN_BSS)
 368                 data->rx_filter |= FIF_PROMISC_IN_BSS;
 369         if (*total_flags & FIF_ALLMULTI)
 370                 data->rx_filter |= FIF_ALLMULTI;
 371
 372         *total_flags = data->rx_filter;
 373 }
 374
 375 static int mac80211_hwsim_config_interface(struct ieee80211_hw *hw,
 376                                            struct ieee80211_vif *vif,
 377                                            struct ieee80211_if_conf *conf)
 378 {
 379         hwsim_check_magic(vif);
 380         return 0;
 381 }
 382
 383 static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw,
 384                                             struct ieee80211_vif *vif,
 385                                             struct ieee80211_bss_conf *info,
 386                                             u32 changed)
 387 {
 388         hwsim_check_magic(vif);
 389 }
 390
 391 static void mac80211_hwsim_sta_notify(struct ieee80211_hw *hw,
 392                                       struct ieee80211_vif *vif,
 393                                       enum sta_notify_cmd cmd, const u8 *addr)
 394 {
 395         hwsim_check_magic(vif);
 396 }
 397
 398 static const struct ieee80211_ops mac80211_hwsim_ops =
 399 {
 400         .tx = mac80211_hwsim_tx,
 401         .start = mac80211_hwsim_start,
 402         .stop = mac80211_hwsim_stop,
 403         .add_interface = mac80211_hwsim_add_interface,
 404         .remove_interface = mac80211_hwsim_remove_interface,
 405         .config = mac80211_hwsim_config,
 406         .configure_filter = mac80211_hwsim_configure_filter,
 407         .config_interface = mac80211_hwsim_config_interface,
 408         .bss_info_changed = mac80211_hwsim_bss_info_changed,
 409         .sta_notify = mac80211_hwsim_sta_notify,
 410 };
 411
 412
 413 static void mac80211_hwsim_free(void)
 414 {
 415         int i;
 416
 417         for (i = 0; i < hwsim_radio_count; i++) {
 418                 if (hwsim_radios[i]) {
 419                         struct mac80211_hwsim_data *data;
 420                         data = hwsim_radios[i]->priv;
 421                         ieee80211_unregister_hw(hwsim_radios[i]);
 422                         device_unregister(data->dev);
 423                         ieee80211_free_hw(hwsim_radios[i]);
 424                 }
 425         }
 426         kfree(hwsim_radios);
 427         class_destroy(hwsim_class);
 428 }
 429
 430
 431 static struct device_driver mac80211_hwsim_driver = {
 432         .name = "mac80211_hwsim"
 433 };
 434
 435
 436 static void hwsim_mon_setup(struct net_device *dev)
 437 {
 438         dev->hard_start_xmit = hwsim_mon_xmit;
 439         dev->destructor = free_netdev;
 440         ether_setup(dev);
 441         dev->tx_queue_len = 0;
 442         dev->type = ARPHRD_IEEE80211_RADIOTAP;
 443         memset(dev->dev_addr, 0, ETH_ALEN);
 444         dev->dev_addr[0] = 0x12;
 445 }
 446
 447
 448 static int __init init_mac80211_hwsim(void)
 449 {
 450         int i, err = 0;
 451         u8 addr[ETH_ALEN];
 452         struct mac80211_hwsim_data *data;
 453         struct ieee80211_hw *hw;
 454         DECLARE_MAC_BUF(mac);
 455
 456         if (radios < 1 || radios > 65535)
 457                 return -EINVAL;
 458
 459         hwsim_radio_count = radios;
 460         hwsim_radios = kcalloc(hwsim_radio_count,
 461                                sizeof(struct ieee80211_hw *), GFP_KERNEL);
 462         if (hwsim_radios == NULL)
 463                 return -ENOMEM;
 464
 465         hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim");
 466         if (IS_ERR(hwsim_class)) {
 467                 kfree(hwsim_radios);
 468                 return PTR_ERR(hwsim_class);
 469         }
 470
 471         memset(addr, 0, ETH_ALEN);
 472         addr[0] = 0x02;
 473
 474         for (i = 0; i < hwsim_radio_count; i++) {
 475                 printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n",
 476                        i);
 477                 hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops);
 478                 if (hw == NULL) {
 479                         printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw "
 480                                "failed\n");
 481                         err = -ENOMEM;
 482                         goto failed;
 483                 }
 484                 hwsim_radios[i] = hw;
 485
 486                 data = hw->priv;
 487                 data->dev = device_create_drvdata(hwsim_class, NULL, 0, hw,
 488                                                 "hwsim%d", i);
 489                 if (IS_ERR(data->dev)) {
 490                         printk(KERN_DEBUG
 491                                "mac80211_hwsim: device_create_drvdata "
 492                                "failed (%ld)\n", PTR_ERR(data->dev));
 493                         err = -ENOMEM;
 494                         goto failed_drvdata;
 495                 }
 496                 data->dev->driver = &mac80211_hwsim_driver;
 497
 498                 SET_IEEE80211_DEV(hw, data->dev);
 499                 addr[3] = i >> 8;
 500                 addr[4] = i;
 501                 SET_IEEE80211_PERM_ADDR(hw, addr);
 502
 503                 hw->channel_change_time = 1;
 504                 hw->queues = 4;
 505                 hw->wiphy->interface_modes =
 506                         BIT(NL80211_IFTYPE_STATION) |
 507                         BIT(NL80211_IFTYPE_AP);
 508                 hw->ampdu_queues = 1;
 509
 510                 /* ask mac80211 to reserve space for magic */
 511                 hw->vif_data_size = sizeof(struct hwsim_vif_priv);
 512
 513                 memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));
 514                 memcpy(data->rates, hwsim_rates, sizeof(hwsim_rates));
 515                 data->band.channels = data->channels;
 516                 data->band.n_channels = ARRAY_SIZE(hwsim_channels);
 517                 data->band.bitrates = data->rates;
 518                 data->band.n_bitrates = ARRAY_SIZE(hwsim_rates);
 519                 data->band.ht_info.ht_supported = 1;
 520                 data->band.ht_info.cap = IEEE80211_HT_CAP_SUP_WIDTH |
 521                         IEEE80211_HT_CAP_GRN_FLD |
 522                         IEEE80211_HT_CAP_SGI_40 |
 523                         IEEE80211_HT_CAP_DSSSCCK40;
 524                 data->band.ht_info.ampdu_factor = 0x3;
 525                 data->band.ht_info.ampdu_density = 0x6;
 526                 memset(data->band.ht_info.supp_mcs_set, 0,
 527                        sizeof(data->band.ht_info.supp_mcs_set));
 528                 data->band.ht_info.supp_mcs_set[0] = 0xff;
 529                 data->band.ht_info.supp_mcs_set[1] = 0xff;
 530                 data->band.ht_info.supp_mcs_set[12] =
 531                         IEEE80211_HT_CAP_MCS_TX_DEFINED;
 532                 hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &data->band;
 533
 534                 err = ieee80211_register_hw(hw);
 535                 if (err < 0) {
 536                         printk(KERN_DEBUG "mac80211_hwsim: "
 537                                "ieee80211_register_hw failed (%d)\n", err);
 538                         goto failed_hw;
 539                 }
 540
 541                 printk(KERN_DEBUG "%s: hwaddr %s registered\n",
 542                        wiphy_name(hw->wiphy),
 543                        print_mac(mac, hw->wiphy->perm_addr));
 544
 545                 setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
 546                             (unsigned long) hw);
 547         }
 548
 549         hwsim_mon = alloc_netdev(0, "hwsim%d", hwsim_mon_setup);
 550         if (hwsim_mon == NULL)
 551                 goto failed;
 552
 553         rtnl_lock();
 554
 555         err = dev_alloc_name(hwsim_mon, hwsim_mon->name);
 556         if (err < 0)
 557                 goto failed_mon;
 558
 559
 560         err = register_netdevice(hwsim_mon);
 561         if (err < 0)
 562                 goto failed_mon;
 563
 564         rtnl_unlock();
 565
 566         return 0;
 567
 568 failed_mon:
 569         rtnl_unlock();
 570         free_netdev(hwsim_mon);
 571         mac80211_hwsim_free();
 572         return err;
 573
 574 failed_hw:
 575         device_unregister(data->dev);
 576 failed_drvdata:
 577         ieee80211_free_hw(hw);
 578         hwsim_radios[i] = NULL;
 579 failed:
 580         mac80211_hwsim_free();
 581         return err;
 582 }
 583
 584
 585 static void __exit exit_mac80211_hwsim(void)
 586 {
 587         printk(KERN_DEBUG "mac80211_hwsim: unregister %d radios\n",
 588                hwsim_radio_count);
 589
 590         unregister_netdev(hwsim_mon);
 591         mac80211_hwsim_free();
 592 }
 593
 594
 595 module_init(init_mac80211_hwsim);
 596 module_exit(exit_mac80211_hwsim);