ieee80211_sta.c

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		return;
	}

	if (sdata->type != IEEE80211_IF_TYPE_IBSS &&
	    memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0) {
		printk(KERN_DEBUG "%s: authentication frame received from "
		       "unknown AP (SA=%s BSSID=%s) - "
		       "ignored\n", dev->name, print_mac(mac, mgmt->sa),
		       print_mac(mac, mgmt->bssid));
		return;
	}

	if (sdata->type != IEEE80211_IF_TYPE_IBSS &&
	    memcmp(ifsta->bssid, mgmt->bssid, ETH_ALEN) != 0) {
		printk(KERN_DEBUG "%s: authentication frame received from "
		       "unknown BSSID (SA=%s BSSID=%s) - "
		       "ignored\n", dev->name, print_mac(mac, mgmt->sa),
		       print_mac(mac, mgmt->bssid));
		return;
	}

	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
	status_code = le16_to_cpu(mgmt->u.auth.status_code);

	printk(KERN_DEBUG "%s: RX authentication from %s (alg=%d "
	       "transaction=%d status=%d)\n",
	       dev->name, print_mac(mac, mgmt->sa), auth_alg,
	       auth_transaction, status_code);

	if (sdata->type == IEEE80211_IF_TYPE_IBSS) {
		/* IEEE 802.11 standard does not require authentication in IBSS
		 * networks and most implementations do not seem to use it.
		 * However, try to reply to authentication attempts if someone
		 * has actually implemented this.
		 * TODO: Could implement shared key authentication. */
		if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) {
			printk(KERN_DEBUG "%s: unexpected IBSS authentication "
			       "frame (alg=%d transaction=%d)\n",
			       dev->name, auth_alg, auth_transaction);
			return;
		}
		ieee80211_send_auth(dev, ifsta, 2, NULL, 0, 0);
	}

	if (auth_alg != ifsta->auth_alg ||
	    auth_transaction != ifsta->auth_transaction) {
		printk(KERN_DEBUG "%s: unexpected authentication frame "
		       "(alg=%d transaction=%d)\n",
		       dev->name, auth_alg, auth_transaction);
		return;
	}

	if (status_code != WLAN_STATUS_SUCCESS) {
		printk(KERN_DEBUG "%s: AP denied authentication (auth_alg=%d "
		       "code=%d)\n", dev->name, ifsta->auth_alg, status_code);
		if (status_code == WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG) {
			u8 algs[3];
			const int num_algs = ARRAY_SIZE(algs);
			int i, pos;
			algs[0] = algs[1] = algs[2] = 0xff;
			if (ifsta->auth_algs & IEEE80211_AUTH_ALG_OPEN)
				algs[0] = WLAN_AUTH_OPEN;
			if (ifsta->auth_algs & IEEE80211_AUTH_ALG_SHARED_KEY)
				algs[1] = WLAN_AUTH_SHARED_KEY;
			if (ifsta->auth_algs & IEEE80211_AUTH_ALG_LEAP)
				algs[2] = WLAN_AUTH_LEAP;
			if (ifsta->auth_alg == WLAN_AUTH_OPEN)
				pos = 0;
			else if (ifsta->auth_alg == WLAN_AUTH_SHARED_KEY)
				pos = 1;
			else
				pos = 2;
			for (i = 0; i < num_algs; i++) {
				pos++;
				if (pos >= num_algs)
					pos = 0;
				if (algs[pos] == ifsta->auth_alg ||
				    algs[pos] == 0xff)
					continue;
				if (algs[pos] == WLAN_AUTH_SHARED_KEY &&
				    !ieee80211_sta_wep_configured(dev))
					continue;
				ifsta->auth_alg = algs[pos];
				printk(KERN_DEBUG "%s: set auth_alg=%d for "
				       "next try\n",
				       dev->name, ifsta->auth_alg);
				break;
			}
		}
		return;
	}

	switch (ifsta->auth_alg) {
	case WLAN_AUTH_OPEN:
	case WLAN_AUTH_LEAP:
		ieee80211_auth_completed(dev, ifsta);
		break;
	case WLAN_AUTH_SHARED_KEY:
		if (ifsta->auth_transaction == 4)
			ieee80211_auth_completed(dev, ifsta);
		else
			ieee80211_auth_challenge(dev, ifsta, mgmt, len);
		break;
	}
}


static void ieee80211_rx_mgmt_deauth(struct net_device *dev,
				     struct ieee80211_if_sta *ifsta,
				     struct ieee80211_mgmt *mgmt,
				     size_t len)
{
	u16 reason_code;
	DECLARE_MAC_BUF(mac);

	if (len < 24 + 2) {
		printk(KERN_DEBUG "%s: too short (%zd) deauthentication frame "
		       "received from %s - ignored\n",
		       dev->name, len, print_mac(mac, mgmt->sa));
		return;
	}

	if (memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0) {
		printk(KERN_DEBUG "%s: deauthentication frame received from "
		       "unknown AP (SA=%s BSSID=%s) - "
		       "ignored\n", dev->name, print_mac(mac, mgmt->sa),
		       print_mac(mac, mgmt->bssid));
		return;
	}

	reason_code = le16_to_cpu(mgmt->u.deauth.reason_code);

	printk(KERN_DEBUG "%s: RX deauthentication from %s"
	       " (reason=%d)\n",
	       dev->name, print_mac(mac, mgmt->sa), reason_code);

	if (ifsta->flags & IEEE80211_STA_AUTHENTICATED) {
		printk(KERN_DEBUG "%s: deauthenticated\n", dev->name);
	}

	if (ifsta->state == IEEE80211_AUTHENTICATE ||
	    ifsta->state == IEEE80211_ASSOCIATE ||
	    ifsta->state == IEEE80211_ASSOCIATED) {
		ifsta->state = IEEE80211_AUTHENTICATE;
		mod_timer(&ifsta->timer, jiffies +
				      IEEE80211_RETRY_AUTH_INTERVAL);
	}

	ieee80211_set_disassoc(dev, ifsta, 1);
	ifsta->flags &= ~IEEE80211_STA_AUTHENTICATED;
}


static void ieee80211_rx_mgmt_disassoc(struct net_device *dev,
				       struct ieee80211_if_sta *ifsta,
				       struct ieee80211_mgmt *mgmt,
				       size_t len)
{
	u16 reason_code;
	DECLARE_MAC_BUF(mac);

	if (len < 24 + 2) {
		printk(KERN_DEBUG "%s: too short (%zd) disassociation frame "
		       "received from %s - ignored\n",
		       dev->name, len, print_mac(mac, mgmt->sa));
		return;
	}

	if (memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0) {
		printk(KERN_DEBUG "%s: disassociation frame received from "
		       "unknown AP (SA=%s BSSID=%s) - "
		       "ignored\n", dev->name, print_mac(mac, mgmt->sa),
		       print_mac(mac, mgmt->bssid));
		return;
	}

	reason_code = le16_to_cpu(mgmt->u.disassoc.reason_code);

	printk(KERN_DEBUG "%s: RX disassociation from %s"
	       " (reason=%d)\n",
	       dev->name, print_mac(mac, mgmt->sa), reason_code);

	if (ifsta->flags & IEEE80211_STA_ASSOCIATED)
		printk(KERN_DEBUG "%s: disassociated\n", dev->name);

	if (ifsta->state == IEEE80211_ASSOCIATED) {
		ifsta->state = IEEE80211_ASSOCIATE;
		mod_timer(&ifsta->timer, jiffies +
				      IEEE80211_RETRY_AUTH_INTERVAL);
	}

	ieee80211_set_disassoc(dev, ifsta, 0);
}


static void ieee80211_rx_mgmt_assoc_resp(struct net_device *dev,
					 struct ieee80211_if_sta *ifsta,
					 struct ieee80211_mgmt *mgmt,
					 size_t len,
					 int reassoc)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_hw_mode *mode;
	struct sta_info *sta;
	u32 rates;
	u16 capab_info, status_code, aid;
	struct ieee802_11_elems elems;
	u8 *pos;
	int i, j;
	DECLARE_MAC_BUF(mac);

	/* AssocResp and ReassocResp have identical structure, so process both
	 * of them in this function. */

	if (ifsta->state != IEEE80211_ASSOCIATE) {
		printk(KERN_DEBUG "%s: association frame received from "
		       "%s, but not in associate state - ignored\n",
		       dev->name, print_mac(mac, mgmt->sa));
		return;
	}

	if (len < 24 + 6) {
		printk(KERN_DEBUG "%s: too short (%zd) association frame "
		       "received from %s - ignored\n",
		       dev->name, len, print_mac(mac, mgmt->sa));
		return;
	}

	if (memcmp(ifsta->bssid, mgmt->sa, ETH_ALEN) != 0) {
		printk(KERN_DEBUG "%s: association frame received from "
		       "unknown AP (SA=%s BSSID=%s) - "
		       "ignored\n", dev->name, print_mac(mac, mgmt->sa),
		       print_mac(mac, mgmt->bssid));
		return;
	}

	capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info);
	status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
	aid = le16_to_cpu(mgmt->u.assoc_resp.aid);

	printk(KERN_DEBUG "%s: RX %sssocResp from %s (capab=0x%x "
	       "status=%d aid=%d)\n",
	       dev->name, reassoc ? "Rea" : "A", print_mac(mac, mgmt->sa),
	       capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));

	if (status_code != WLAN_STATUS_SUCCESS) {
		printk(KERN_DEBUG "%s: AP denied association (code=%d)\n",
		       dev->name, status_code);
		/* if this was a reassociation, ensure we try a "full"
		 * association next time. This works around some broken APs
		 * which do not correctly reject reassociation requests. */
		ifsta->flags &= ~IEEE80211_STA_PREV_BSSID_SET;
		return;
	}

	if ((aid & (BIT(15) | BIT(14))) != (BIT(15) | BIT(14)))
		printk(KERN_DEBUG "%s: invalid aid value %d; bits 15:14 not "
		       "set\n", dev->name, aid);
	aid &= ~(BIT(15) | BIT(14));

	pos = mgmt->u.assoc_resp.variable;
	ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);

	if (!elems.supp_rates) {
		printk(KERN_DEBUG "%s: no SuppRates element in AssocResp\n",
		       dev->name);
		return;
	}

	/* it probably doesn't, but if the frame includes an ERP value then
	 * update our stored copy */
	if (elems.erp_info && elems.erp_info_len >= 1) {
		struct ieee80211_sta_bss *bss
			= ieee80211_rx_bss_get(dev, ifsta->bssid,
					       local->hw.conf.channel,
					       ifsta->ssid, ifsta->ssid_len);
		if (bss) {
			bss->erp_value = elems.erp_info[0];
			bss->has_erp_value = 1;
			ieee80211_rx_bss_put(dev, bss);
		}
	}

	printk(KERN_DEBUG "%s: associated\n", dev->name);
	ifsta->aid = aid;
	ifsta->ap_capab = capab_info;

	kfree(ifsta->assocresp_ies);
	ifsta->assocresp_ies_len = len - (pos - (u8 *) mgmt);
	ifsta->assocresp_ies = kmalloc(ifsta->assocresp_ies_len, GFP_KERNEL);
	if (ifsta->assocresp_ies)
		memcpy(ifsta->assocresp_ies, pos, ifsta->assocresp_ies_len);

	ieee80211_set_associated(dev, ifsta, 1);

	/* Add STA entry for the AP */
	sta = sta_info_get(local, ifsta->bssid);
	if (!sta) {
		struct ieee80211_sta_bss *bss;
		sta = sta_info_add(local, dev, ifsta->bssid, GFP_KERNEL);
		if (!sta) {
			printk(KERN_DEBUG "%s: failed to add STA entry for the"
			       " AP\n", dev->name);
			return;
		}
		bss = ieee80211_rx_bss_get(dev, ifsta->bssid,
					   local->hw.conf.channel,
					   ifsta->ssid, ifsta->ssid_len);
		if (bss) {
			sta->last_rssi = bss->rssi;
			sta->last_signal = bss->signal;
			sta->last_noise = bss->noise;
			ieee80211_rx_bss_put(dev, bss);
		}
	}

	sta->dev = dev;
	sta->flags |= WLAN_STA_AUTH | WLAN_STA_ASSOC | WLAN_STA_ASSOC_AP;

	rates = 0;
	mode = local->oper_hw_mode;
	for (i = 0; i < elems.supp_rates_len; i++) {
		int rate = (elems.supp_rates[i] & 0x7f) * 5;
		for (j = 0; j < mode->num_rates; j++)
			if (mode->rates[j].rate == rate)
				rates |= BIT(j);
	}
	for (i = 0; i < elems.ext_supp_rates_len; i++) {
		int rate = (elems.ext_supp_rates[i] & 0x7f) * 5;
		for (j = 0; j < mode->num_rates; j++)
			if (mode->rates[j].rate == rate)
				rates |= BIT(j);
	}
	sta->supp_rates = rates;

	rate_control_rate_init(sta, local);

	if (elems.wmm_param && (ifsta->flags & IEEE80211_STA_WMM_ENABLED)) {
		sta->flags |= WLAN_STA_WME;
		ieee80211_sta_wmm_params(dev, ifsta, elems.wmm_param,
					 elems.wmm_param_len);
	}


	sta_info_put(sta);

	ieee80211_associated(dev, ifsta);
}


/* Caller must hold local->sta_bss_lock */
static void __ieee80211_rx_bss_hash_add(struct net_device *dev,
					struct ieee80211_sta_bss *bss)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	bss->hnext = local->sta_bss_hash[STA_HASH(bss->bssid)];
	local->sta_bss_hash[STA_HASH(bss->bssid)] = bss;
}


/* Caller must hold local->sta_bss_lock */
static void __ieee80211_rx_bss_hash_del(struct net_device *dev,
					struct ieee80211_sta_bss *bss)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_sta_bss *b, *prev = NULL;
	b = local->sta_bss_hash[STA_HASH(bss->bssid)];
	while (b) {
		if (b == bss) {
			if (!prev)
				local->sta_bss_hash[STA_HASH(bss->bssid)] =
					bss->hnext;
			else
				prev->hnext = bss->hnext;
			break;
		}
		prev = b;
		b = b->hnext;
	}
}


static struct ieee80211_sta_bss *
ieee80211_rx_bss_add(struct net_device *dev, u8 *bssid, int channel,
		     u8 *ssid, u8 ssid_len)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_sta_bss *bss;

	bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
	if (!bss)
		return NULL;
	atomic_inc(&bss->users);
	atomic_inc(&bss->users);
	memcpy(bss->bssid, bssid, ETH_ALEN);
	bss->channel = channel;
	if (ssid && ssid_len <= IEEE80211_MAX_SSID_LEN) {
		memcpy(bss->ssid, ssid, ssid_len);
		bss->ssid_len = ssid_len;
	}

	spin_lock_bh(&local->sta_bss_lock);
	/* TODO: order by RSSI? */
	list_add_tail(&bss->list, &local->sta_bss_list);
	__ieee80211_rx_bss_hash_add(dev, bss);
	spin_unlock_bh(&local->sta_bss_lock);
	return bss;
}


static struct ieee80211_sta_bss *
ieee80211_rx_bss_get(struct net_device *dev, u8 *bssid, int channel,
		     u8 *ssid, u8 ssid_len)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_sta_bss *bss;

	spin_lock_bh(&local->sta_bss_lock);
	bss = local->sta_bss_hash[STA_HASH(bssid)];
	while (bss) {
		if (!memcmp(bss->bssid, bssid, ETH_ALEN) &&
		    bss->channel == channel &&
		    bss->ssid_len == ssid_len &&
		    (ssid_len == 0 || !memcmp(bss->ssid, ssid, ssid_len))) {
			atomic_inc(&bss->users);
			break;
		}
		bss = bss->hnext;
	}
	spin_unlock_bh(&local->sta_bss_lock);
	return bss;
}


static void ieee80211_rx_bss_free(struct ieee80211_sta_bss *bss)
{
	kfree(bss->wpa_ie);
	kfree(bss->rsn_ie);
	kfree(bss->wmm_ie);
	kfree(bss);
}


static void ieee80211_rx_bss_put(struct net_device *dev,
				 struct ieee80211_sta_bss *bss)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	if (!atomic_dec_and_test(&bss->users))
		return;

	spin_lock_bh(&local->sta_bss_lock);
	__ieee80211_rx_bss_hash_del(dev, bss);
	list_del(&bss->list);
	spin_unlock_bh(&local->sta_bss_lock);
	ieee80211_rx_bss_free(bss);
}


void ieee80211_rx_bss_list_init(struct net_device *dev)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	spin_lock_init(&local->sta_bss_lock);
	INIT_LIST_HEAD(&local->sta_bss_list);
}


void ieee80211_rx_bss_list_deinit(struct net_device *dev)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_sta_bss *bss, *tmp;