/* * mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211 * Copyright (c) 2008, Jouni Malinen * * 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 #include #include #include #include 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"); static struct class *hwsim_class; static struct ieee80211_hw **hwsim_radios; static int hwsim_radio_count; 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 } }; struct mac80211_hwsim_data { 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 = 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 int mac80211_hwsim_tx_frame(struct ieee80211_hw *hw, struct sk_buff *skb) { struct mac80211_hwsim_data *data = hw->priv; int i, ack = 0; 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 */ for (i = 0; i < hwsim_radio_count; i++) { struct mac80211_hwsim_data *data2; struct sk_buff *nskb; if (hwsim_radios[i] == NULL || hwsim_radios[i] == hw) continue; data2 = hwsim_radios[i]->priv; 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, hwsim_radios[i]->wiphy->perm_addr, ETH_ALEN) == 0) ack = 1; ieee80211_rx_irqsafe(hwsim_radios[i], nskb, &rx_status); } return ack; } static int mac80211_hwsim_tx(struct ieee80211_hw *hw, struct sk_buff *skb) { struct mac80211_hwsim_data *data = hw->priv; int 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); 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)); 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)); } 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; if (vif->type != IEEE80211_IF_TYPE_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 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, }; static void mac80211_hwsim_free(void) { int i; for (i = 0; i < hwsim_radio_count; i++) { if (hwsim_radios[i]) { struct mac80211_hwsim_data *data; data = hwsim_radios[i]->priv; ieee80211_unregister_hw(hwsim_radios[i]); if (!IS_ERR(data->dev)) device_unregister(data->dev); ieee80211_free_hw(hwsim_radios[i]); } } kfree(hwsim_radios); 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 > 65535) return -EINVAL; hwsim_radio_count = radios; hwsim_radios = kcalloc(hwsim_radio_count, sizeof(struct ieee80211_hw *), GFP_KERNEL); if (hwsim_radios == NULL) return -ENOMEM; hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim"); if (IS_ERR(hwsim_class)) { kfree(hwsim_radios); return PTR_ERR(hwsim_class); } memset(addr, 0, ETH_ALEN); addr[0] = 0x02; for (i = 0; i < hwsim_radio_count; i++) { printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n", i); hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops); if (hw == NULL) { printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw " "failed\n"); err = -ENOMEM; goto failed; } hwsim_radios[i] = hw; data = hw->priv; data->dev = device_create(hwsim_class, NULL, 0, "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; } data->dev->driver = &mac80211_hwsim_driver; dev_set_drvdata(data->dev, hw); 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 = 1; 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); 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; } 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); } 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); failed: mac80211_hwsim_free(); return err; } static void __exit exit_mac80211_hwsim(void) { printk(KERN_DEBUG "mac80211_hwsim: unregister %d radios\n", hwsim_radio_count); unregister_netdev(hwsim_mon); mac80211_hwsim_free(); } module_init(init_mac80211_hwsim); module_exit(exit_mac80211_hwsim);