cfg.c

/*
 * mac80211 configuration hooks for cfg80211
 *
 * Copyright 2006, 2007	Johannes Berg <johannes@sipsolutions.net>
 *
 * This file is GPLv2 as found in COPYING.
 */

#include <linux/ieee80211.h>
#include <linux/nl80211.h>
#include <linux/rtnetlink.h>
#include <net/net_namespace.h>
#include <linux/rcupdate.h>
#include <net/cfg80211.h>
#include "ieee80211_i.h"
#include "cfg.h"
#include "ieee80211_rate.h"

static enum ieee80211_if_types
nl80211_type_to_mac80211_type(enum nl80211_iftype type)
{
	switch (type) {
	case NL80211_IFTYPE_UNSPECIFIED:
		return IEEE80211_IF_TYPE_STA;
	case NL80211_IFTYPE_ADHOC:
		return IEEE80211_IF_TYPE_IBSS;
	case NL80211_IFTYPE_STATION:
		return IEEE80211_IF_TYPE_STA;
	case NL80211_IFTYPE_MONITOR:
		return IEEE80211_IF_TYPE_MNTR;
	default:
		return IEEE80211_IF_TYPE_INVALID;
	}
}

static int ieee80211_add_iface(struct wiphy *wiphy, char *name,
			       enum nl80211_iftype type, u32 *flags,
			       struct vif_params *params)
{
	struct ieee80211_local *local = wiphy_priv(wiphy);
	enum ieee80211_if_types itype;
	struct net_device *dev;
	struct ieee80211_sub_if_data *sdata;
	int err;

	if (unlikely(local->reg_state != IEEE80211_DEV_REGISTERED))
		return -ENODEV;

	itype = nl80211_type_to_mac80211_type(type);
	if (itype == IEEE80211_IF_TYPE_INVALID)
		return -EINVAL;

	err = ieee80211_if_add(local->mdev, name, &dev, itype, params);
	if (err || itype != IEEE80211_IF_TYPE_MNTR || !flags)
		return err;

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	sdata->u.mntr_flags = *flags;
	return 0;
}

static int ieee80211_del_iface(struct wiphy *wiphy, int ifindex)
{
	struct ieee80211_local *local = wiphy_priv(wiphy);
	struct net_device *dev;
	char *name;

	if (unlikely(local->reg_state != IEEE80211_DEV_REGISTERED))
		return -ENODEV;

	/* we're under RTNL */
	dev = __dev_get_by_index(&init_net, ifindex);
	if (!dev)
		return 0;

	name = dev->name;

	return ieee80211_if_remove(local->mdev, name, -1);
}

static int ieee80211_change_iface(struct wiphy *wiphy, int ifindex,
				  enum nl80211_iftype type, u32 *flags,
				  struct vif_params *params)
{
	struct ieee80211_local *local = wiphy_priv(wiphy);
	struct net_device *dev;
	enum ieee80211_if_types itype;
	struct ieee80211_sub_if_data *sdata;

	if (unlikely(local->reg_state != IEEE80211_DEV_REGISTERED))
		return -ENODEV;

	/* we're under RTNL */
	dev = __dev_get_by_index(&init_net, ifindex);
	if (!dev)
		return -ENODEV;

	if (netif_running(dev))
		return -EBUSY;

	itype = nl80211_type_to_mac80211_type(type);
	if (itype == IEEE80211_IF_TYPE_INVALID)
		return -EINVAL;

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);

	if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN)
		return -EOPNOTSUPP;

	ieee80211_if_reinit(dev);
	ieee80211_if_set_type(dev, itype);

	if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR || !flags)
		return 0;

	sdata->u.mntr_flags = *flags;
	return 0;
}

static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev,
			     u8 key_idx, u8 *mac_addr,
			     struct key_params *params)
{
	struct ieee80211_sub_if_data *sdata;
	struct sta_info *sta = NULL;
	enum ieee80211_key_alg alg;
	int ret;
	struct ieee80211_key *key;

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);

	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_WEP40:
	case WLAN_CIPHER_SUITE_WEP104:
		alg = ALG_WEP;
		break;
	case WLAN_CIPHER_SUITE_TKIP:
		alg = ALG_TKIP;
		break;
	case WLAN_CIPHER_SUITE_CCMP:
		alg = ALG_CCMP;
		break;
	default:
		return -EINVAL;
	}

	key = ieee80211_key_alloc(alg, key_idx, params->key_len, params->key);
	if (!key)
		return -ENOMEM;

	if (mac_addr) {
		sta = sta_info_get(sdata->local, mac_addr);
		if (!sta) {
			ieee80211_key_free(key);
			return -ENOENT;
		}
	}

	ieee80211_key_link(key, sdata, sta);

	ret = 0;

	if (sta)
		sta_info_put(sta);

	return ret;
}

static int ieee80211_del_key(struct wiphy *wiphy, struct net_device *dev,
			     u8 key_idx, u8 *mac_addr)
{
	struct ieee80211_sub_if_data *sdata;
	struct sta_info *sta;
	int ret;
	struct ieee80211_key *key;

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);

	if (mac_addr) {
		sta = sta_info_get(sdata->local, mac_addr);
		if (!sta)
			return -ENOENT;

		ret = 0;
		if (sta->key) {
			key = sta->key;
			ieee80211_key_free(key);
			WARN_ON(sta->key);
		} else
			ret = -ENOENT;

		sta_info_put(sta);
		return ret;
	}

	if (!sdata->keys[key_idx])
		return -ENOENT;

	key = sdata->keys[key_idx];
	ieee80211_key_free(key);
	WARN_ON(sdata->keys[key_idx]);

	return 0;
}

static int ieee80211_get_key(struct wiphy *wiphy, struct net_device *dev,
			     u8 key_idx, u8 *mac_addr, void *cookie,
			     void (*callback)(void *cookie,
					      struct key_params *params))
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct sta_info *sta = NULL;
	u8 seq[6] = {0};
	struct key_params params;
	struct ieee80211_key *key;
	u32 iv32;
	u16 iv16;
	int err = -ENOENT;

	if (mac_addr) {
		sta = sta_info_get(sdata->local, mac_addr);
		if (!sta)
			goto out;

		key = sta->key;
	} else
		key = sdata->keys[key_idx];

	if (!key)
		goto out;

	memset(&params, 0, sizeof(params));

	switch (key->conf.alg) {
	case ALG_TKIP:
		params.cipher = WLAN_CIPHER_SUITE_TKIP;

		iv32 = key->u.tkip.iv32;
		iv16 = key->u.tkip.iv16;

		if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE &&
		    sdata->local->ops->get_tkip_seq)
			sdata->local->ops->get_tkip_seq(
				local_to_hw(sdata->local),
				key->conf.hw_key_idx,
				&iv32, &iv16);

		seq[0] = iv16 & 0xff;
		seq[1] = (iv16 >> 8) & 0xff;
		seq[2] = iv32 & 0xff;
		seq[3] = (iv32 >> 8) & 0xff;
		seq[4] = (iv32 >> 16) & 0xff;
		seq[5] = (iv32 >> 24) & 0xff;
		params.seq = seq;
		params.seq_len = 6;
		break;
	case ALG_CCMP:
		params.cipher = WLAN_CIPHER_SUITE_CCMP;
		seq[0] = key->u.ccmp.tx_pn[5];
		seq[1] = key->u.ccmp.tx_pn[4];
		seq[2] = key->u.ccmp.tx_pn[3];
		seq[3] = key->u.ccmp.tx_pn[2];
		seq[4] = key->u.ccmp.tx_pn[1];
		seq[5] = key->u.ccmp.tx_pn[0];
		params.seq = seq;
		params.seq_len = 6;
		break;
	case ALG_WEP:
		if (key->conf.keylen == 5)
			params.cipher = WLAN_CIPHER_SUITE_WEP40;
		else
			params.cipher = WLAN_CIPHER_SUITE_WEP104;
		break;
	}

	params.key = key->conf.key;
	params.key_len = key->conf.keylen;

	callback(cookie, &params);
	err = 0;

 out:
	if (sta)
		sta_info_put(sta);
	return err;
}

static int ieee80211_config_default_key(struct wiphy *wiphy,
					struct net_device *dev,
					u8 key_idx)
{
	struct ieee80211_sub_if_data *sdata;

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	ieee80211_set_default_key(sdata, key_idx);

	return 0;
}

static int ieee80211_get_station(struct wiphy *wiphy, struct net_device *dev,
				 u8 *mac, struct station_info *sinfo)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sta_info *sta;

	sta = sta_info_get(local, mac);
	if (!sta)
		return -ENOENT;

	/* XXX: verify sta->dev == dev */

	sinfo->filled = STATION_INFO_INACTIVE_TIME |
			STATION_INFO_RX_BYTES |
			STATION_INFO_TX_BYTES;

	sinfo->inactive_time = jiffies_to_msecs(jiffies - sta->last_rx);
	sinfo->rx_bytes = sta->rx_bytes;
	sinfo->tx_bytes = sta->tx_bytes;

	sta_info_put(sta);

	return 0;
}

/*
 * This handles both adding a beacon and setting new beacon info
 */
static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
				   struct beacon_parameters *params)
{
	struct beacon_data *new, *old;
	int new_head_len, new_tail_len;
	int size;
	int err = -EINVAL;

	old = sdata->u.ap.beacon;

	/* head must not be zero-length */
	if (params->head && !params->head_len)
		return -EINVAL;

	/*
	 * This is a kludge. beacon interval should really be part
	 * of the beacon information.
	 */
	if (params->interval) {
		sdata->local->hw.conf.beacon_int = params->interval;
		if (ieee80211_hw_config(sdata->local))
			return -EINVAL;
		/*
		 * We updated some parameter so if below bails out
		 * it's not an error.
		 */
		err = 0;
	}

	/* Need to have a beacon head if we don't have one yet */
	if (!params->head && !old)
		return err;

	/* sorry, no way to start beaconing without dtim period */
	if (!params->dtim_period && !old)
		return err;

	/* new or old head? */
	if (params->head)
		new_head_len = params->head_len;
	else
		new_head_len = old->head_len;

	/* new or old tail? */
	if (params->tail || !old)
		/* params->tail_len will be zero for !params->tail */
		new_tail_len = params->tail_len;
	else
		new_tail_len = old->tail_len;

	size = sizeof(*new) + new_head_len + new_tail_len;

	new = kzalloc(size, GFP_KERNEL);
	if (!new)
		return -ENOMEM;

	/* start filling the new info now */

	/* new or old dtim period? */
	if (params->dtim_period)
		new->dtim_period = params->dtim_period;
	else
		new->dtim_period = old->dtim_period;

	/*
	 * pointers go into the block we allocated,
	 * memory is | beacon_data | head | tail |
	 */
	new->head = ((u8 *) new) + sizeof(*new);
	new->tail = new->head + new_head_len;
	new->head_len = new_head_len;
	new->tail_len = new_tail_len;

	/* copy in head */
	if (params->head)
		memcpy(new->head, params->head, new_head_len);
	else
		memcpy(new->head, old->head, new_head_len);

	/* copy in optional tail */
	if (params->tail)
		memcpy(new->tail, params->tail, new_tail_len);
	else
		if (old)
			memcpy(new->tail, old->tail, new_tail_len);

	rcu_assign_pointer(sdata->u.ap.beacon, new);

	synchronize_rcu();

	kfree(old);

	return ieee80211_if_config_beacon(sdata->dev);
}

static int ieee80211_add_beacon(struct wiphy *wiphy, struct net_device *dev,
				struct beacon_parameters *params)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct beacon_data *old;

	if (sdata->vif.type != IEEE80211_IF_TYPE_AP)
		return -EINVAL;

	old = sdata->u.ap.beacon;

	if (old)
		return -EALREADY;

	return ieee80211_config_beacon(sdata, params);
}

static int ieee80211_set_beacon(struct wiphy *wiphy, struct net_device *dev,
				struct beacon_parameters *params)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct beacon_data *old;

	if (sdata->vif.type != IEEE80211_IF_TYPE_AP)
		return -EINVAL;

	old = sdata->u.ap.beacon;

	if (!old)
		return -ENOENT;

	return ieee80211_config_beacon(sdata, params);
}

static int ieee80211_del_beacon(struct wiphy *wiphy, struct net_device *dev)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct beacon_data *old;

	if (sdata->vif.type != IEEE80211_IF_TYPE_AP)
		return -EINVAL;

	old = sdata->u.ap.beacon;

	if (!old)
		return -ENOENT;

	rcu_assign_pointer(sdata->u.ap.beacon, NULL);
	synchronize_rcu();
	kfree(old);

	return ieee80211_if_config_beacon(dev);
}

/* Layer 2 Update frame (802.2 Type 1 LLC XID Update response) */
struct iapp_layer2_update {
	u8 da[ETH_ALEN];	/* broadcast */
	u8 sa[ETH_ALEN];	/* STA addr */
	__be16 len;		/* 6 */
	u8 dsap;		/* 0 */
	u8 ssap;		/* 0 */
	u8 control;
	u8 xid_info[3];
} __attribute__ ((packed));

static void ieee80211_send_layer2_update(struct sta_info *sta)
{
	struct iapp_layer2_update *msg;
	struct sk_buff *skb;

	/* Send Level 2 Update Frame to update forwarding tables in layer 2
	 * bridge devices */

	skb = dev_alloc_skb(sizeof(*msg));
	if (!skb)
		return;
	msg = (struct iapp_layer2_update *)skb_put(skb, sizeof(*msg));

	/* 802.2 Type 1 Logical Link Control (LLC) Exchange Identifier (XID)
	 * Update response frame; IEEE Std 802.2-1998, 5.4.1.2.1 */

	memset(msg->da, 0xff, ETH_ALEN);
	memcpy(msg->sa, sta->addr, ETH_ALEN);
	msg->len = htons(6);
	msg->dsap = 0;
	msg->ssap = 0x01;	/* NULL LSAP, CR Bit: Response */
	msg->control = 0xaf;	/* XID response lsb.1111F101.
				 * F=0 (no poll command; unsolicited frame) */
	msg->xid_info[0] = 0x81;	/* XID format identifier */
	msg->xid_info[1] = 1;	/* LLC types/classes: Type 1 LLC */
	msg->xid_info[2] = 0;	/* XID sender's receive window size (RW) */

	skb->dev = sta->dev;
	skb->protocol = eth_type_trans(skb, sta->dev);
	memset(skb->cb, 0, sizeof(skb->cb));
	netif_rx(skb);
}

static void sta_apply_parameters(struct ieee80211_local *local,
				 struct sta_info *sta,
				 struct station_parameters *params)
{
	u32 rates;
	int i, j;
	struct ieee80211_supported_band *sband;

	if (params->station_flags & STATION_FLAG_CHANGED) {
		sta->flags &= ~WLAN_STA_AUTHORIZED;
		if (params->station_flags & STATION_FLAG_AUTHORIZED)
			sta->flags |= WLAN_STA_AUTHORIZED;

		sta->flags &= ~WLAN_STA_SHORT_PREAMBLE;
		if (params->station_flags & STATION_FLAG_SHORT_PREAMBLE)
			sta->flags |= WLAN_STA_SHORT_PREAMBLE;

		sta->flags &= ~WLAN_STA_WME;
		if (params->station_flags & STATION_FLAG_WME)
			sta->flags |= WLAN_STA_WME;
	}

	if (params->aid) {
		sta->aid = params->aid;
		if (sta->aid > IEEE80211_MAX_AID)
			sta->aid = 0; /* XXX: should this be an error? */
	}

	if (params->listen_interval >= 0)
		sta->listen_interval = params->listen_interval;

	if (params->supported_rates) {
		rates = 0;
		sband = local->hw.wiphy->bands[local->oper_channel->band];

		for (i = 0; i < params->supported_rates_len; i++) {
			int rate = (params->supported_rates[i] & 0x7f) * 5;
			for (j = 0; j < sband->n_bitrates; j++) {
				if (sband->bitrates[j].bitrate == rate)
					rates |= BIT(j);
			}
		}
		sta->supp_rates[local->oper_channel->band] = rates;
	}
}

static int ieee80211_add_station(struct wiphy *wiphy, struct net_device *dev,
				 u8 *mac, struct station_parameters *params)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sta_info *sta;
	struct ieee80211_sub_if_data *sdata;

	/* Prevent a race with changing the rate control algorithm */
	if (!netif_running(dev))
		return -ENETDOWN;

	if (params->vlan) {
		sdata = IEEE80211_DEV_TO_SUB_IF(params->vlan);

		if (sdata->vif.type != IEEE80211_IF_TYPE_VLAN ||
		    sdata->vif.type != IEEE80211_IF_TYPE_AP)
			return -EINVAL;
	} else
		sdata = IEEE80211_DEV_TO_SUB_IF(dev);

	sta = sta_info_add(local, dev, mac, GFP_KERNEL);
	if (IS_ERR(sta))
		return PTR_ERR(sta);

	sta->dev = sdata->dev;
	if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN ||
	    sdata->vif.type == IEEE80211_IF_TYPE_AP)
		ieee80211_send_layer2_update(sta);

	sta->flags = WLAN_STA_AUTH | WLAN_STA_ASSOC;

	sta_apply_parameters(local, sta, params);

	rate_control_rate_init(sta, local);

	sta_info_put(sta);

	return 0;
}

static int ieee80211_del_station(struct wiphy *wiphy, struct net_device *dev,
				 u8 *mac)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sta_info *sta;

	if (mac) {
		/* XXX: get sta belonging to dev */
		sta = sta_info_get(local, mac);
		if (!sta)
			return -ENOENT;

		sta_info_free(sta);
		sta_info_put(sta);
	} else
		sta_info_flush(local, dev);

	return 0;
}

static int ieee80211_change_station(struct wiphy *wiphy,
				    struct net_device *dev,
				    u8 *mac,
				    struct station_parameters *params)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sta_info *sta;
	struct ieee80211_sub_if_data *vlansdata;

	/* XXX: get sta belonging to dev */
	sta = sta_info_get(local, mac);
	if (!sta)
		return -ENOENT;

	if (params->vlan && params->vlan != sta->dev) {
		vlansdata = IEEE80211_DEV_TO_SUB_IF(params->vlan);

		if (vlansdata->vif.type != IEEE80211_IF_TYPE_VLAN ||
		    vlansdata->vif.type != IEEE80211_IF_TYPE_AP)
			return -EINVAL;

		sta->dev = params->vlan;
		ieee80211_send_layer2_update(sta);
	}

	sta_apply_parameters(local, sta, params);

	sta_info_put(sta);

	return 0;
}

struct cfg80211_ops mac80211_config_ops = {
	.add_virtual_intf = ieee80211_add_iface,
	.del_virtual_intf = ieee80211_del_iface,
	.change_virtual_intf = ieee80211_change_iface,
	.add_key = ieee80211_add_key,
	.del_key = ieee80211_del_key,
	.get_key = ieee80211_get_key,
	.set_default_key = ieee80211_config_default_key,
	.add_beacon = ieee80211_add_beacon,
	.set_beacon = ieee80211_set_beacon,
	.del_beacon = ieee80211_del_beacon,
	.add_station = ieee80211_add_station,
	.del_station = ieee80211_del_station,
	.change_station = ieee80211_change_station,
	.get_station = ieee80211_get_station,
};