linux/net/mac80211/tdls.c

568 lines
15 KiB
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/*
* mac80211 TDLS handling code
*
* Copyright 2006-2010 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2014, Intel Corporation
*
* This file is GPLv2 as found in COPYING.
*/
#include <linux/ieee80211.h>
#include <net/cfg80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
/* give usermode some time for retries in setting up the TDLS session */
#define TDLS_PEER_SETUP_TIMEOUT (15 * HZ)
void ieee80211_tdls_peer_del_work(struct work_struct *wk)
{
struct ieee80211_sub_if_data *sdata;
struct ieee80211_local *local;
sdata = container_of(wk, struct ieee80211_sub_if_data,
tdls_peer_del_work.work);
local = sdata->local;
mutex_lock(&local->mtx);
if (!is_zero_ether_addr(sdata->tdls_peer)) {
tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->tdls_peer);
sta_info_destroy_addr(sdata, sdata->tdls_peer);
eth_zero_addr(sdata->tdls_peer);
}
mutex_unlock(&local->mtx);
}
static void ieee80211_tdls_add_ext_capab(struct sk_buff *skb)
{
u8 *pos = (void *)skb_put(skb, 7);
*pos++ = WLAN_EID_EXT_CAPABILITY;
*pos++ = 5; /* len */
*pos++ = 0x0;
*pos++ = 0x0;
*pos++ = 0x0;
*pos++ = 0x0;
*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
}
static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
u16 capab;
capab = 0;
if (ieee80211_get_sdata_band(sdata) != IEEE80211_BAND_2GHZ)
return capab;
if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
return capab;
}
static void ieee80211_tdls_add_link_ie(struct sk_buff *skb, const u8 *src_addr,
const u8 *peer, const u8 *bssid)
{
struct ieee80211_tdls_lnkie *lnkid;
lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
lnkid->ie_type = WLAN_EID_LINK_ID;
lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
memcpy(lnkid->bssid, bssid, ETH_ALEN);
memcpy(lnkid->init_sta, src_addr, ETH_ALEN);
memcpy(lnkid->resp_sta, peer, ETH_ALEN);
}
static int
ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code, u8 dialog_token,
u16 status_code, struct sk_buff *skb)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
struct ieee80211_tdls_data *tf;
tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
memcpy(tf->da, peer, ETH_ALEN);
memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
tf->ether_type = cpu_to_be16(ETH_P_TDLS);
tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
switch (action_code) {
case WLAN_TDLS_SETUP_REQUEST:
tf->category = WLAN_CATEGORY_TDLS;
tf->action_code = WLAN_TDLS_SETUP_REQUEST;
skb_put(skb, sizeof(tf->u.setup_req));
tf->u.setup_req.dialog_token = dialog_token;
tf->u.setup_req.capability =
cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
ieee80211_add_srates_ie(sdata, skb, false, band);
ieee80211_add_ext_srates_ie(sdata, skb, false, band);
ieee80211_tdls_add_ext_capab(skb);
break;
case WLAN_TDLS_SETUP_RESPONSE:
tf->category = WLAN_CATEGORY_TDLS;
tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
skb_put(skb, sizeof(tf->u.setup_resp));
tf->u.setup_resp.status_code = cpu_to_le16(status_code);
tf->u.setup_resp.dialog_token = dialog_token;
tf->u.setup_resp.capability =
cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
ieee80211_add_srates_ie(sdata, skb, false, band);
ieee80211_add_ext_srates_ie(sdata, skb, false, band);
ieee80211_tdls_add_ext_capab(skb);
break;
case WLAN_TDLS_SETUP_CONFIRM:
tf->category = WLAN_CATEGORY_TDLS;
tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
skb_put(skb, sizeof(tf->u.setup_cfm));
tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
tf->u.setup_cfm.dialog_token = dialog_token;
break;
case WLAN_TDLS_TEARDOWN:
tf->category = WLAN_CATEGORY_TDLS;
tf->action_code = WLAN_TDLS_TEARDOWN;
skb_put(skb, sizeof(tf->u.teardown));
tf->u.teardown.reason_code = cpu_to_le16(status_code);
break;
case WLAN_TDLS_DISCOVERY_REQUEST:
tf->category = WLAN_CATEGORY_TDLS;
tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
skb_put(skb, sizeof(tf->u.discover_req));
tf->u.discover_req.dialog_token = dialog_token;
break;
default:
return -EINVAL;
}
return 0;
}
static int
ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code, u8 dialog_token,
u16 status_code, struct sk_buff *skb)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
struct ieee80211_mgmt *mgmt;
mgmt = (void *)skb_put(skb, 24);
memset(mgmt, 0, 24);
memcpy(mgmt->da, peer, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
switch (action_code) {
case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
mgmt->u.action.u.tdls_discover_resp.action_code =
WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
mgmt->u.action.u.tdls_discover_resp.dialog_token =
dialog_token;
mgmt->u.action.u.tdls_discover_resp.capability =
cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
ieee80211_add_srates_ie(sdata, skb, false, band);
ieee80211_add_ext_srates_ie(sdata, skb, false, band);
ieee80211_tdls_add_ext_capab(skb);
break;
default:
return -EINVAL;
}
return 0;
}
static int
ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code,
u8 dialog_token, u16 status_code,
u32 peer_capability, bool initiator,
const u8 *extra_ies, size_t extra_ies_len)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb = NULL;
bool send_direct;
const u8 *init_addr, *rsp_addr;
struct sta_info *sta;
int ret;
skb = dev_alloc_skb(local->hw.extra_tx_headroom +
max(sizeof(struct ieee80211_mgmt),
sizeof(struct ieee80211_tdls_data)) +
50 + /* supported rates */
7 + /* ext capab */
extra_ies_len +
sizeof(struct ieee80211_tdls_lnkie));
if (!skb)
return -ENOMEM;
skb_reserve(skb, local->hw.extra_tx_headroom);
switch (action_code) {
case WLAN_TDLS_SETUP_REQUEST:
case WLAN_TDLS_SETUP_RESPONSE:
case WLAN_TDLS_SETUP_CONFIRM:
case WLAN_TDLS_TEARDOWN:
case WLAN_TDLS_DISCOVERY_REQUEST:
ret = ieee80211_prep_tdls_encap_data(wiphy, dev, peer,
action_code, dialog_token,
status_code, skb);
send_direct = false;
break;
case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
ret = ieee80211_prep_tdls_direct(wiphy, dev, peer, action_code,
dialog_token, status_code,
skb);
send_direct = true;
break;
default:
ret = -ENOTSUPP;
break;
}
if (ret < 0)
goto fail;
if (extra_ies_len)
memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
rcu_read_lock();
sta = sta_info_get(sdata, peer);
/* infer the initiator if we can, to support old userspace */
switch (action_code) {
case WLAN_TDLS_SETUP_REQUEST:
if (sta)
set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
/* fall-through */
case WLAN_TDLS_SETUP_CONFIRM:
case WLAN_TDLS_DISCOVERY_REQUEST:
initiator = true;
break;
case WLAN_TDLS_SETUP_RESPONSE:
/*
* In some testing scenarios, we send a request and response.
* Make the last packet sent take effect for the initiator
* value.
*/
if (sta)
clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
/* fall-through */
case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
initiator = false;
break;
case WLAN_TDLS_TEARDOWN:
/* any value is ok */
break;
default:
ret = -ENOTSUPP;
break;
}
if (initiator || (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))) {
init_addr = sdata->vif.addr;
rsp_addr = peer;
} else {
init_addr = peer;
rsp_addr = sdata->vif.addr;
}
rcu_read_unlock();
if (ret < 0)
goto fail;
ieee80211_tdls_add_link_ie(skb, init_addr, rsp_addr,
sdata->u.mgd.bssid);
if (send_direct) {
ieee80211_tx_skb(sdata, skb);
return 0;
}
/*
* According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
* we should default to AC_VI.
*/
switch (action_code) {
case WLAN_TDLS_SETUP_REQUEST:
case WLAN_TDLS_SETUP_RESPONSE:
skb_set_queue_mapping(skb, IEEE80211_AC_BK);
skb->priority = 2;
break;
default:
skb_set_queue_mapping(skb, IEEE80211_AC_VI);
skb->priority = 5;
break;
}
/* disable bottom halves when entering the Tx path */
local_bh_disable();
ret = ieee80211_subif_start_xmit(skb, dev);
local_bh_enable();
return ret;
fail:
dev_kfree_skb(skb);
return ret;
}
static int
ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code, u8 dialog_token,
u16 status_code, u32 peer_capability, bool initiator,
const u8 *extra_ies, size_t extra_ies_len)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
int ret;
mutex_lock(&local->mtx);
/* we don't support concurrent TDLS peer setups */
if (!is_zero_ether_addr(sdata->tdls_peer) &&
!ether_addr_equal(sdata->tdls_peer, peer)) {
ret = -EBUSY;
goto exit;
}
/*
* make sure we have a STA representing the peer so we drop or buffer
* non-TDLS-setup frames to the peer. We can't send other packets
* during setup through the AP path
*/
rcu_read_lock();
if (!sta_info_get(sdata, peer)) {
rcu_read_unlock();
ret = -ENOLINK;
goto exit;
}
rcu_read_unlock();
ieee80211_flush_queues(local, sdata);
ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
dialog_token, status_code,
peer_capability, initiator,
extra_ies, extra_ies_len);
if (ret < 0)
goto exit;
memcpy(sdata->tdls_peer, peer, ETH_ALEN);
ieee80211_queue_delayed_work(&sdata->local->hw,
&sdata->tdls_peer_del_work,
TDLS_PEER_SETUP_TIMEOUT);
exit:
mutex_unlock(&local->mtx);
return ret;
}
static int
ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code, u8 dialog_token,
u16 status_code, u32 peer_capability,
bool initiator, const u8 *extra_ies,
size_t extra_ies_len)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
int ret;
/*
* No packets can be transmitted to the peer via the AP during setup -
* the STA is set as a TDLS peer, but is not authorized.
* During teardown, we prevent direct transmissions by stopping the
* queues and flushing all direct packets.
*/
ieee80211_stop_vif_queues(local, sdata,
IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
ieee80211_flush_queues(local, sdata);
ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
dialog_token, status_code,
peer_capability, initiator,
extra_ies, extra_ies_len);
if (ret < 0)
sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
ret);
/*
* Remove the STA AUTH flag to force further traffic through the AP. If
* the STA was unreachable, it was already removed.
*/
rcu_read_lock();
sta = sta_info_get(sdata, peer);
if (sta)
clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
rcu_read_unlock();
ieee80211_wake_vif_queues(local, sdata,
IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
return 0;
}
int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, u8 action_code, u8 dialog_token,
u16 status_code, u32 peer_capability,
bool initiator, const u8 *extra_ies,
size_t extra_ies_len)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
int ret;
if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
return -ENOTSUPP;
/* make sure we are in managed mode, and associated */
if (sdata->vif.type != NL80211_IFTYPE_STATION ||
!sdata->u.mgd.associated)
return -EINVAL;
switch (action_code) {
case WLAN_TDLS_SETUP_REQUEST:
case WLAN_TDLS_SETUP_RESPONSE:
ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
dialog_token, status_code,
peer_capability, initiator,
extra_ies, extra_ies_len);
break;
case WLAN_TDLS_TEARDOWN:
ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
action_code, dialog_token,
status_code,
peer_capability, initiator,
extra_ies, extra_ies_len);
break;
case WLAN_TDLS_DISCOVERY_REQUEST:
/*
* Protect the discovery so we can hear the TDLS discovery
* response frame. It is transmitted directly and not buffered
* by the AP.
*/
drv_mgd_protect_tdls_discover(sdata->local, sdata);
/* fall-through */
case WLAN_TDLS_SETUP_CONFIRM:
case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
/* no special handling */
ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
action_code,
dialog_token,
status_code,
peer_capability,
initiator, extra_ies,
extra_ies_len);
break;
default:
ret = -EOPNOTSUPP;
break;
}
tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
action_code, peer, ret);
return ret;
}
int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, enum nl80211_tdls_operation oper)
{
struct sta_info *sta;
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
int ret;
if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
return -ENOTSUPP;
if (sdata->vif.type != NL80211_IFTYPE_STATION)
return -EINVAL;
switch (oper) {
case NL80211_TDLS_ENABLE_LINK:
case NL80211_TDLS_DISABLE_LINK:
break;
case NL80211_TDLS_TEARDOWN:
case NL80211_TDLS_SETUP:
case NL80211_TDLS_DISCOVERY_REQ:
/* We don't support in-driver setup/teardown/discovery */
return -ENOTSUPP;
}
mutex_lock(&local->mtx);
tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
switch (oper) {
case NL80211_TDLS_ENABLE_LINK:
rcu_read_lock();
sta = sta_info_get(sdata, peer);
if (!sta) {
rcu_read_unlock();
ret = -ENOLINK;
break;
}
set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
rcu_read_unlock();
WARN_ON_ONCE(is_zero_ether_addr(sdata->tdls_peer) ||
!ether_addr_equal(sdata->tdls_peer, peer));
ret = 0;
break;
case NL80211_TDLS_DISABLE_LINK:
/* flush a potentially queued teardown packet */
ieee80211_flush_queues(local, sdata);
ret = sta_info_destroy_addr(sdata, peer);
break;
default:
ret = -ENOTSUPP;
break;
}
if (ret == 0 && ether_addr_equal(sdata->tdls_peer, peer)) {
cancel_delayed_work(&sdata->tdls_peer_del_work);
eth_zero_addr(sdata->tdls_peer);
}
mutex_unlock(&local->mtx);
return ret;
}
void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
enum nl80211_tdls_operation oper,
u16 reason_code, gfp_t gfp)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
oper);
return;
}
cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
}
EXPORT_SYMBOL(ieee80211_tdls_oper_request);