blob: 248d31a7aa33ff8c7990c6a4b6231729be589c8b [file] [log] [blame]
/*
* 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 <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");
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 = 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 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]);
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_drvdata(hwsim_class, NULL, 0, hw,
"hwsim%d", i);
if (IS_ERR(data->dev)) {
printk(KERN_DEBUG
"mac80211_hwsim: device_create_drvdata "
"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 = 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_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);
}
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);
hwsim_radios[i] = NULL;
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);