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alistair23-linux/net/wireless/scan.c
Emmanuel Grumbach 2f1805ea20 cfg80211: allow the low level driver to flush the BSS table 
The low level driver adds its own opaque information
in the BSS table in the cfg80211_bss structure.

The low level driver may need to signal that this information
is no longer relevant and needs to be recreated.
Add an API to allow the low level driver to do that.

iwlwifi needs this because it keeps there an information about
the firmware's internal clock. This is kept in mac80211's
struct ieee80211_bss::sync_device_ts.
This information is populated while we scan, we add the
internal firmware's clock to each beacon which allows us to
program the firmware correctly after association so that
it'll know when (in terms of its internal clock) the DTIM
and TBTT will happen.

When the firmware is reset this internal clock is reset as
well and ieee80211_bss::sync_device_ts is no longer accurate.

iwlwifi will call this new API any time the firmware is started.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://lore.kernel.org/r/20200625111524.3992-1-emmanuel.grumbach@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-07-31 09:24:23 +02:00

2626 lines
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// SPDX-License-Identifier: GPL-2.0
/*
* cfg80211 scan result handling
*
* Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2013-2014 Intel Mobile Communications GmbH
* Copyright 2016 Intel Deutschland GmbH
* Copyright (C) 2018-2019 Intel Corporation
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/wireless.h>
#include <linux/nl80211.h>
#include <linux/etherdevice.h>
#include <net/arp.h>
#include <net/cfg80211.h>
#include <net/cfg80211-wext.h>
#include <net/iw_handler.h>
#include "core.h"
#include "nl80211.h"
#include "wext-compat.h"
#include "rdev-ops.h"
/**
* DOC: BSS tree/list structure
*
* At the top level, the BSS list is kept in both a list in each
* registered device (@bss_list) as well as an RB-tree for faster
* lookup. In the RB-tree, entries can be looked up using their
* channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
* for other BSSes.
*
* Due to the possibility of hidden SSIDs, there's a second level
* structure, the "hidden_list" and "hidden_beacon_bss" pointer.
* The hidden_list connects all BSSes belonging to a single AP
* that has a hidden SSID, and connects beacon and probe response
* entries. For a probe response entry for a hidden SSID, the
* hidden_beacon_bss pointer points to the BSS struct holding the
* beacon's information.
*
* Reference counting is done for all these references except for
* the hidden_list, so that a beacon BSS struct that is otherwise
* not referenced has one reference for being on the bss_list and
* one for each probe response entry that points to it using the
* hidden_beacon_bss pointer. When a BSS struct that has such a
* pointer is get/put, the refcount update is also propagated to
* the referenced struct, this ensure that it cannot get removed
* while somebody is using the probe response version.
*
* Note that the hidden_beacon_bss pointer never changes, due to
* the reference counting. Therefore, no locking is needed for
* it.
*
* Also note that the hidden_beacon_bss pointer is only relevant
* if the driver uses something other than the IEs, e.g. private
* data stored stored in the BSS struct, since the beacon IEs are
* also linked into the probe response struct.
*/
/*
* Limit the number of BSS entries stored in mac80211. Each one is
* a bit over 4k at most, so this limits to roughly 4-5M of memory.
* If somebody wants to really attack this though, they'd likely
* use small beacons, and only one type of frame, limiting each of
* the entries to a much smaller size (in order to generate more
* entries in total, so overhead is bigger.)
*/
static int bss_entries_limit = 1000;
module_param(bss_entries_limit, int, 0644);
MODULE_PARM_DESC(bss_entries_limit,
"limit to number of scan BSS entries (per wiphy, default 1000)");
#define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
static void bss_free(struct cfg80211_internal_bss *bss)
{
struct cfg80211_bss_ies *ies;
if (WARN_ON(atomic_read(&bss->hold)))
return;
ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
if (ies && !bss->pub.hidden_beacon_bss)
kfree_rcu(ies, rcu_head);
ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
if (ies)
kfree_rcu(ies, rcu_head);
/*
* This happens when the module is removed, it doesn't
* really matter any more save for completeness
*/
if (!list_empty(&bss->hidden_list))
list_del(&bss->hidden_list);
kfree(bss);
}
static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *bss)
{
lockdep_assert_held(&rdev->bss_lock);
bss->refcount++;
if (bss->pub.hidden_beacon_bss) {
bss = container_of(bss->pub.hidden_beacon_bss,
struct cfg80211_internal_bss,
pub);
bss->refcount++;
}
if (bss->pub.transmitted_bss) {
bss = container_of(bss->pub.transmitted_bss,
struct cfg80211_internal_bss,
pub);
bss->refcount++;
}
}
static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *bss)
{
lockdep_assert_held(&rdev->bss_lock);
if (bss->pub.hidden_beacon_bss) {
struct cfg80211_internal_bss *hbss;
hbss = container_of(bss->pub.hidden_beacon_bss,
struct cfg80211_internal_bss,
pub);
hbss->refcount--;
if (hbss->refcount == 0)
bss_free(hbss);
}
if (bss->pub.transmitted_bss) {
struct cfg80211_internal_bss *tbss;
tbss = container_of(bss->pub.transmitted_bss,
struct cfg80211_internal_bss,
pub);
tbss->refcount--;
if (tbss->refcount == 0)
bss_free(tbss);
}
bss->refcount--;
if (bss->refcount == 0)
bss_free(bss);
}
static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *bss)
{
lockdep_assert_held(&rdev->bss_lock);
if (!list_empty(&bss->hidden_list)) {
/*
* don't remove the beacon entry if it has
* probe responses associated with it
*/
if (!bss->pub.hidden_beacon_bss)
return false;
/*
* if it's a probe response entry break its
* link to the other entries in the group
*/
list_del_init(&bss->hidden_list);
}
list_del_init(&bss->list);
list_del_init(&bss->pub.nontrans_list);
rb_erase(&bss->rbn, &rdev->bss_tree);
rdev->bss_entries--;
WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
"rdev bss entries[%d]/list[empty:%d] corruption\n",
rdev->bss_entries, list_empty(&rdev->bss_list));
bss_ref_put(rdev, bss);
return true;
}
bool cfg80211_is_element_inherited(const struct element *elem,
const struct element *non_inherit_elem)
{
u8 id_len, ext_id_len, i, loop_len, id;
const u8 *list;
if (elem->id == WLAN_EID_MULTIPLE_BSSID)
return false;
if (!non_inherit_elem || non_inherit_elem->datalen < 2)
return true;
/*
* non inheritance element format is:
* ext ID (56) | IDs list len | list | extension IDs list len | list
* Both lists are optional. Both lengths are mandatory.
* This means valid length is:
* elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
*/
id_len = non_inherit_elem->data[1];
if (non_inherit_elem->datalen < 3 + id_len)
return true;
ext_id_len = non_inherit_elem->data[2 + id_len];
if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
return true;
if (elem->id == WLAN_EID_EXTENSION) {
if (!ext_id_len)
return true;
loop_len = ext_id_len;
list = &non_inherit_elem->data[3 + id_len];
id = elem->data[0];
} else {
if (!id_len)
return true;
loop_len = id_len;
list = &non_inherit_elem->data[2];
id = elem->id;
}
for (i = 0; i < loop_len; i++) {
if (list[i] == id)
return false;
}
return true;
}
EXPORT_SYMBOL(cfg80211_is_element_inherited);
static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
const u8 *subelement, size_t subie_len,
u8 *new_ie, gfp_t gfp)
{
u8 *pos, *tmp;
const u8 *tmp_old, *tmp_new;
const struct element *non_inherit_elem;
u8 *sub_copy;
/* copy subelement as we need to change its content to
* mark an ie after it is processed.
*/
sub_copy = kmemdup(subelement, subie_len, gfp);
if (!sub_copy)
return 0;
pos = &new_ie[0];
/* set new ssid */
tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
if (tmp_new) {
memcpy(pos, tmp_new, tmp_new[1] + 2);
pos += (tmp_new[1] + 2);
}
/* get non inheritance list if exists */
non_inherit_elem =
cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
sub_copy, subie_len);
/* go through IEs in ie (skip SSID) and subelement,
* merge them into new_ie
*/
tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {
if (tmp_old[0] == 0) {
tmp_old++;
continue;
}
if (tmp_old[0] == WLAN_EID_EXTENSION)
tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
subie_len);
else
tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
subie_len);
if (!tmp) {
const struct element *old_elem = (void *)tmp_old;
/* ie in old ie but not in subelement */
if (cfg80211_is_element_inherited(old_elem,
non_inherit_elem)) {
memcpy(pos, tmp_old, tmp_old[1] + 2);
pos += tmp_old[1] + 2;
}
} else {
/* ie in transmitting ie also in subelement,
* copy from subelement and flag the ie in subelement
* as copied (by setting eid field to WLAN_EID_SSID,
* which is skipped anyway).
* For vendor ie, compare OUI + type + subType to
* determine if they are the same ie.
*/
if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
if (!memcmp(tmp_old + 2, tmp + 2, 5)) {
/* same vendor ie, copy from
* subelement
*/
memcpy(pos, tmp, tmp[1] + 2);
pos += tmp[1] + 2;
tmp[0] = WLAN_EID_SSID;
} else {
memcpy(pos, tmp_old, tmp_old[1] + 2);
pos += tmp_old[1] + 2;
}
} else {
/* copy ie from subelement into new ie */
memcpy(pos, tmp, tmp[1] + 2);
pos += tmp[1] + 2;
tmp[0] = WLAN_EID_SSID;
}
}
if (tmp_old + tmp_old[1] + 2 - ie == ielen)
break;
tmp_old += tmp_old[1] + 2;
}
/* go through subelement again to check if there is any ie not
* copied to new ie, skip ssid, capability, bssid-index ie
*/
tmp_new = sub_copy;
while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
tmp_new[0] == WLAN_EID_SSID)) {
memcpy(pos, tmp_new, tmp_new[1] + 2);
pos += tmp_new[1] + 2;
}
if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
break;
tmp_new += tmp_new[1] + 2;
}
kfree(sub_copy);
return pos - new_ie;
}
static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
const u8 *ssid, size_t ssid_len)
{
const struct cfg80211_bss_ies *ies;
const u8 *ssidie;
if (bssid && !ether_addr_equal(a->bssid, bssid))
return false;
if (!ssid)
return true;
ies = rcu_access_pointer(a->ies);
if (!ies)
return false;
ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
if (!ssidie)
return false;
if (ssidie[1] != ssid_len)
return false;
return memcmp(ssidie + 2, ssid, ssid_len) == 0;
}
static int
cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
struct cfg80211_bss *nontrans_bss)
{
const u8 *ssid;
size_t ssid_len;
struct cfg80211_bss *bss = NULL;
rcu_read_lock();
ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
if (!ssid) {
rcu_read_unlock();
return -EINVAL;
}
ssid_len = ssid[1];
ssid = ssid + 2;
rcu_read_unlock();
/* check if nontrans_bss is in the list */
list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
return 0;
}
/* add to the list */
list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
return 0;
}
static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
unsigned long expire_time)
{
struct cfg80211_internal_bss *bss, *tmp;
bool expired = false;
lockdep_assert_held(&rdev->bss_lock);
list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
if (atomic_read(&bss->hold))
continue;
if (!time_after(expire_time, bss->ts))
continue;
if (__cfg80211_unlink_bss(rdev, bss))
expired = true;
}
if (expired)
rdev->bss_generation++;
}
static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
{
struct cfg80211_internal_bss *bss, *oldest = NULL;
bool ret;
lockdep_assert_held(&rdev->bss_lock);
list_for_each_entry(bss, &rdev->bss_list, list) {
if (atomic_read(&bss->hold))
continue;
if (!list_empty(&bss->hidden_list) &&
!bss->pub.hidden_beacon_bss)
continue;
if (oldest && time_before(oldest->ts, bss->ts))
continue;
oldest = bss;
}
if (WARN_ON(!oldest))
return false;
/*
* The callers make sure to increase rdev->bss_generation if anything
* gets removed (and a new entry added), so there's no need to also do
* it here.
*/
ret = __cfg80211_unlink_bss(rdev, oldest);
WARN_ON(!ret);
return ret;
}
void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
bool send_message)
{
struct cfg80211_scan_request *request;
struct wireless_dev *wdev;
struct sk_buff *msg;
#ifdef CONFIG_CFG80211_WEXT
union iwreq_data wrqu;
#endif
ASSERT_RTNL();
if (rdev->scan_msg) {
nl80211_send_scan_msg(rdev, rdev->scan_msg);
rdev->scan_msg = NULL;
return;
}
request = rdev->scan_req;
if (!request)
return;
wdev = request->wdev;
/*
* This must be before sending the other events!
* Otherwise, wpa_supplicant gets completely confused with
* wext events.
*/
if (wdev->netdev)
cfg80211_sme_scan_done(wdev->netdev);
if (!request->info.aborted &&
request->flags & NL80211_SCAN_FLAG_FLUSH) {
/* flush entries from previous scans */
spin_lock_bh(&rdev->bss_lock);
__cfg80211_bss_expire(rdev, request->scan_start);
spin_unlock_bh(&rdev->bss_lock);
}
msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
#ifdef CONFIG_CFG80211_WEXT
if (wdev->netdev && !request->info.aborted) {
memset(&wrqu, 0, sizeof(wrqu));
wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
}
#endif
if (wdev->netdev)
dev_put(wdev->netdev);
rdev->scan_req = NULL;
kfree(request);
if (!send_message)
rdev->scan_msg = msg;
else
nl80211_send_scan_msg(rdev, msg);
}
void __cfg80211_scan_done(struct work_struct *wk)
{
struct cfg80211_registered_device *rdev;
rdev = container_of(wk, struct cfg80211_registered_device,
scan_done_wk);
rtnl_lock();
___cfg80211_scan_done(rdev, true);
rtnl_unlock();
}
void cfg80211_scan_done(struct cfg80211_scan_request *request,
struct cfg80211_scan_info *info)
{
trace_cfg80211_scan_done(request, info);
WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
request->info = *info;
request->notified = true;
queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
}
EXPORT_SYMBOL(cfg80211_scan_done);
void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
struct cfg80211_sched_scan_request *req)
{
ASSERT_RTNL();
list_add_rcu(&req->list, &rdev->sched_scan_req_list);
}
static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
struct cfg80211_sched_scan_request *req)
{
ASSERT_RTNL();
list_del_rcu(&req->list);
kfree_rcu(req, rcu_head);
}
static struct cfg80211_sched_scan_request *
cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
{
struct cfg80211_sched_scan_request *pos;
list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
lockdep_rtnl_is_held()) {
if (pos->reqid == reqid)
return pos;
}
return NULL;
}
/*
* Determines if a scheduled scan request can be handled. When a legacy
* scheduled scan is running no other scheduled scan is allowed regardless
* whether the request is for legacy or multi-support scan. When a multi-support
* scheduled scan is running a request for legacy scan is not allowed. In this
* case a request for multi-support scan can be handled if resources are
* available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
*/
int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
bool want_multi)
{
struct cfg80211_sched_scan_request *pos;
int i = 0;
list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
/* request id zero means legacy in progress */
if (!i && !pos->reqid)
return -EINPROGRESS;
i++;
}
if (i) {
/* no legacy allowed when multi request(s) are active */
if (!want_multi)
return -EINPROGRESS;
/* resource limit reached */
if (i == rdev->wiphy.max_sched_scan_reqs)
return -ENOSPC;
}
return 0;
}
void cfg80211_sched_scan_results_wk(struct work_struct *work)
{
struct cfg80211_registered_device *rdev;
struct cfg80211_sched_scan_request *req, *tmp;
rdev = container_of(work, struct cfg80211_registered_device,
sched_scan_res_wk);
rtnl_lock();
list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
if (req->report_results) {
req->report_results = false;
if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
/* flush entries from previous scans */
spin_lock_bh(&rdev->bss_lock);
__cfg80211_bss_expire(rdev, req->scan_start);
spin_unlock_bh(&rdev->bss_lock);
req->scan_start = jiffies;
}
nl80211_send_sched_scan(req,
NL80211_CMD_SCHED_SCAN_RESULTS);
}
}
rtnl_unlock();
}
void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_sched_scan_request *request;
trace_cfg80211_sched_scan_results(wiphy, reqid);
/* ignore if we're not scanning */
rcu_read_lock();
request = cfg80211_find_sched_scan_req(rdev, reqid);
if (request) {
request->report_results = true;
queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
}
rcu_read_unlock();
}
EXPORT_SYMBOL(cfg80211_sched_scan_results);
void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy, u64 reqid)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
ASSERT_RTNL();
trace_cfg80211_sched_scan_stopped(wiphy, reqid);
__cfg80211_stop_sched_scan(rdev, reqid, true);
}
EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
{
rtnl_lock();
cfg80211_sched_scan_stopped_rtnl(wiphy, reqid);
rtnl_unlock();
}
EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
struct cfg80211_sched_scan_request *req,
bool driver_initiated)
{
ASSERT_RTNL();
if (!driver_initiated) {
int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
if (err)
return err;
}
nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
cfg80211_del_sched_scan_req(rdev, req);
return 0;
}
int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
u64 reqid, bool driver_initiated)
{
struct cfg80211_sched_scan_request *sched_scan_req;
ASSERT_RTNL();
sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
if (!sched_scan_req)
return -ENOENT;
return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
driver_initiated);
}
void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
unsigned long age_secs)
{
struct cfg80211_internal_bss *bss;
unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
spin_lock_bh(&rdev->bss_lock);
list_for_each_entry(bss, &rdev->bss_list, list)
bss->ts -= age_jiffies;
spin_unlock_bh(&rdev->bss_lock);
}
void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
{
__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
}
void cfg80211_bss_flush(struct wiphy *wiphy)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
spin_lock_bh(&rdev->bss_lock);
__cfg80211_bss_expire(rdev, jiffies);
spin_unlock_bh(&rdev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_bss_flush);
const struct element *
cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
const u8 *match, unsigned int match_len,
unsigned int match_offset)
{
const struct element *elem;
for_each_element_id(elem, eid, ies, len) {
if (elem->datalen >= match_offset + match_len &&
!memcmp(elem->data + match_offset, match, match_len))
return elem;
}
return NULL;
}
EXPORT_SYMBOL(cfg80211_find_elem_match);
const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
const u8 *ies,
unsigned int len)
{
const struct element *elem;
u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
int match_len = (oui_type < 0) ? 3 : sizeof(match);
if (WARN_ON(oui_type > 0xff))
return NULL;
elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
match, match_len, 0);
if (!elem || elem->datalen < 4)
return NULL;
return elem;
}
EXPORT_SYMBOL(cfg80211_find_vendor_elem);
/**
* enum bss_compare_mode - BSS compare mode
* @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
* @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
* @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
*/
enum bss_compare_mode {
BSS_CMP_REGULAR,
BSS_CMP_HIDE_ZLEN,
BSS_CMP_HIDE_NUL,
};
static int cmp_bss(struct cfg80211_bss *a,
struct cfg80211_bss *b,
enum bss_compare_mode mode)
{
const struct cfg80211_bss_ies *a_ies, *b_ies;
const u8 *ie1 = NULL;
const u8 *ie2 = NULL;
int i, r;
if (a->channel != b->channel)
return b->channel->center_freq - a->channel->center_freq;
a_ies = rcu_access_pointer(a->ies);
if (!a_ies)
return -1;
b_ies = rcu_access_pointer(b->ies);
if (!b_ies)
return 1;
if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
a_ies->data, a_ies->len);
if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
b_ies->data, b_ies->len);
if (ie1 && ie2) {
int mesh_id_cmp;
if (ie1[1] == ie2[1])
mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
else
mesh_id_cmp = ie2[1] - ie1[1];
ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
a_ies->data, a_ies->len);
ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
b_ies->data, b_ies->len);
if (ie1 && ie2) {
if (mesh_id_cmp)
return mesh_id_cmp;
if (ie1[1] != ie2[1])
return ie2[1] - ie1[1];
return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
}
}
r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
if (r)
return r;
ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
if (!ie1 && !ie2)
return 0;
/*
* Note that with "hide_ssid", the function returns a match if
* the already-present BSS ("b") is a hidden SSID beacon for
* the new BSS ("a").
*/
/* sort missing IE before (left of) present IE */
if (!ie1)
return -1;
if (!ie2)
return 1;
switch (mode) {
case BSS_CMP_HIDE_ZLEN:
/*
* In ZLEN mode we assume the BSS entry we're
* looking for has a zero-length SSID. So if
* the one we're looking at right now has that,
* return 0. Otherwise, return the difference
* in length, but since we're looking for the
* 0-length it's really equivalent to returning
* the length of the one we're looking at.
*
* No content comparison is needed as we assume
* the content length is zero.
*/
return ie2[1];
case BSS_CMP_REGULAR:
default:
/* sort by length first, then by contents */
if (ie1[1] != ie2[1])
return ie2[1] - ie1[1];
return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
case BSS_CMP_HIDE_NUL:
if (ie1[1] != ie2[1])
return ie2[1] - ie1[1];
/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
for (i = 0; i < ie2[1]; i++)
if (ie2[i + 2])
return -1;
return 0;
}
}
static bool cfg80211_bss_type_match(u16 capability,
enum nl80211_band band,
enum ieee80211_bss_type bss_type)
{
bool ret = true;
u16 mask, val;
if (bss_type == IEEE80211_BSS_TYPE_ANY)
return ret;
if (band == NL80211_BAND_60GHZ) {
mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
switch (bss_type) {
case IEEE80211_BSS_TYPE_ESS:
val = WLAN_CAPABILITY_DMG_TYPE_AP;
break;
case IEEE80211_BSS_TYPE_PBSS:
val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
break;
case IEEE80211_BSS_TYPE_IBSS:
val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
break;
default:
return false;
}
} else {
mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
switch (bss_type) {
case IEEE80211_BSS_TYPE_ESS:
val = WLAN_CAPABILITY_ESS;
break;
case IEEE80211_BSS_TYPE_IBSS:
val = WLAN_CAPABILITY_IBSS;
break;
case IEEE80211_BSS_TYPE_MBSS:
val = 0;
break;
default:
return false;
}
}
ret = ((capability & mask) == val);
return ret;
}
/* Returned bss is reference counted and must be cleaned up appropriately. */
struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
struct ieee80211_channel *channel,
const u8 *bssid,
const u8 *ssid, size_t ssid_len,
enum ieee80211_bss_type bss_type,
enum ieee80211_privacy privacy)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *bss, *res = NULL;
unsigned long now = jiffies;
int bss_privacy;
trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
privacy);
spin_lock_bh(&rdev->bss_lock);
list_for_each_entry(bss, &rdev->bss_list, list) {
if (!cfg80211_bss_type_match(bss->pub.capability,
bss->pub.channel->band, bss_type))
continue;
bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
(privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
continue;
if (channel && bss->pub.channel != channel)
continue;
if (!is_valid_ether_addr(bss->pub.bssid))
continue;
/* Don't get expired BSS structs */
if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
!atomic_read(&bss->hold))
continue;
if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
res = bss;
bss_ref_get(rdev, res);
break;
}
}
spin_unlock_bh(&rdev->bss_lock);
if (!res)
return NULL;
trace_cfg80211_return_bss(&res->pub);
return &res->pub;
}
EXPORT_SYMBOL(cfg80211_get_bss);
static void rb_insert_bss(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *bss)
{
struct rb_node **p = &rdev->bss_tree.rb_node;
struct rb_node *parent = NULL;
struct cfg80211_internal_bss *tbss;
int cmp;
while (*p) {
parent = *p;
tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
if (WARN_ON(!cmp)) {
/* will sort of leak this BSS */
return;
}
if (cmp < 0)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&bss->rbn, parent, p);
rb_insert_color(&bss->rbn, &rdev->bss_tree);
}
static struct cfg80211_internal_bss *
rb_find_bss(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *res,
enum bss_compare_mode mode)
{
struct rb_node *n = rdev->bss_tree.rb_node;
struct cfg80211_internal_bss *bss;
int r;
while (n) {
bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
r = cmp_bss(&res->pub, &bss->pub, mode);
if (r == 0)
return bss;
else if (r < 0)
n = n->rb_left;
else
n = n->rb_right;
}
return NULL;
}
static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *new)
{
const struct cfg80211_bss_ies *ies;
struct cfg80211_internal_bss *bss;
const u8 *ie;
int i, ssidlen;
u8 fold = 0;
u32 n_entries = 0;
ies = rcu_access_pointer(new->pub.beacon_ies);
if (WARN_ON(!ies))
return false;
ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
if (!ie) {
/* nothing to do */
return true;
}
ssidlen = ie[1];
for (i = 0; i < ssidlen; i++)
fold |= ie[2 + i];
if (fold) {
/* not a hidden SSID */
return true;
}
/* This is the bad part ... */
list_for_each_entry(bss, &rdev->bss_list, list) {
/*
* we're iterating all the entries anyway, so take the
* opportunity to validate the list length accounting
*/
n_entries++;
if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
continue;
if (bss->pub.channel != new->pub.channel)
continue;
if (bss->pub.scan_width != new->pub.scan_width)
continue;
if (rcu_access_pointer(bss->pub.beacon_ies))
continue;
ies = rcu_access_pointer(bss->pub.ies);
if (!ies)
continue;
ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
if (!ie)
continue;
if (ssidlen && ie[1] != ssidlen)
continue;
if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
continue;
if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
list_del(&bss->hidden_list);
/* combine them */
list_add(&bss->hidden_list, &new->hidden_list);
bss->pub.hidden_beacon_bss = &new->pub;
new->refcount += bss->refcount;
rcu_assign_pointer(bss->pub.beacon_ies,
new->pub.beacon_ies);
}
WARN_ONCE(n_entries != rdev->bss_entries,
"rdev bss entries[%d]/list[len:%d] corruption\n",
rdev->bss_entries, n_entries);
return true;
}
struct cfg80211_non_tx_bss {
struct cfg80211_bss *tx_bss;
u8 max_bssid_indicator;
u8 bssid_index;
};
static bool
cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *known,
struct cfg80211_internal_bss *new,
bool signal_valid)
{
lockdep_assert_held(&rdev->bss_lock);
/* Update IEs */
if (rcu_access_pointer(new->pub.proberesp_ies)) {
const struct cfg80211_bss_ies *old;
old = rcu_access_pointer(known->pub.proberesp_ies);
rcu_assign_pointer(known->pub.proberesp_ies,
new->pub.proberesp_ies);
/* Override possible earlier Beacon frame IEs */
rcu_assign_pointer(known->pub.ies,
new->pub.proberesp_ies);
if (old)
kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
} else if (rcu_access_pointer(new->pub.beacon_ies)) {
const struct cfg80211_bss_ies *old;
struct cfg80211_internal_bss *bss;
if (known->pub.hidden_beacon_bss &&
!list_empty(&known->hidden_list)) {
const struct cfg80211_bss_ies *f;
/* The known BSS struct is one of the probe
* response members of a group, but we're
* receiving a beacon (beacon_ies in the new
* bss is used). This can only mean that the
* AP changed its beacon from not having an
* SSID to showing it, which is confusing so
* drop this information.
*/
f = rcu_access_pointer(new->pub.beacon_ies);
kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
return false;
}
old = rcu_access_pointer(known->pub.beacon_ies);
rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
/* Override IEs if they were from a beacon before */
if (old == rcu_access_pointer(known->pub.ies))
rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
/* Assign beacon IEs to all sub entries */
list_for_each_entry(bss, &known->hidden_list, hidden_list) {
const struct cfg80211_bss_ies *ies;
ies = rcu_access_pointer(bss->pub.beacon_ies);
WARN_ON(ies != old);
rcu_assign_pointer(bss->pub.beacon_ies,
new->pub.beacon_ies);
}
if (old)
kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
}
known->pub.beacon_interval = new->pub.beacon_interval;
/* don't update the signal if beacon was heard on
* adjacent channel.
*/
if (signal_valid)
known->pub.signal = new->pub.signal;
known->pub.capability = new->pub.capability;
known->ts = new->ts;
known->ts_boottime = new->ts_boottime;
known->parent_tsf = new->parent_tsf;
known->pub.chains = new->pub.chains;
memcpy(known->pub.chain_signal, new->pub.chain_signal,
IEEE80211_MAX_CHAINS);
ether_addr_copy(known->parent_bssid, new->parent_bssid);
known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
known->pub.bssid_index = new->pub.bssid_index;
return true;
}
/* Returned bss is reference counted and must be cleaned up appropriately. */
struct cfg80211_internal_bss *
cfg80211_bss_update(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *tmp,
bool signal_valid, unsigned long ts)
{
struct cfg80211_internal_bss *found = NULL;
if (WARN_ON(!tmp->pub.channel))
return NULL;
tmp->ts = ts;
spin_lock_bh(&rdev->bss_lock);
if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
spin_unlock_bh(&rdev->bss_lock);
return NULL;
}
found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
if (found) {
if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
goto drop;
} else {
struct cfg80211_internal_bss *new;
struct cfg80211_internal_bss *hidden;
struct cfg80211_bss_ies *ies;
/*
* create a copy -- the "res" variable that is passed in
* is allocated on the stack since it's not needed in the
* more common case of an update
*/
new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
GFP_ATOMIC);
if (!new) {
ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
if (ies)
kfree_rcu(ies, rcu_head);
ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
if (ies)
kfree_rcu(ies, rcu_head);
goto drop;
}
memcpy(new, tmp, sizeof(*new));
new->refcount = 1;
INIT_LIST_HEAD(&new->hidden_list);
INIT_LIST_HEAD(&new->pub.nontrans_list);
if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
if (!hidden)
hidden = rb_find_bss(rdev, tmp,
BSS_CMP_HIDE_NUL);
if (hidden) {
new->pub.hidden_beacon_bss = &hidden->pub;
list_add(&new->hidden_list,
&hidden->hidden_list);
hidden->refcount++;
rcu_assign_pointer(new->pub.beacon_ies,
hidden->pub.beacon_ies);
}
} else {
/*
* Ok so we found a beacon, and don't have an entry. If
* it's a beacon with hidden SSID, we might be in for an
* expensive search for any probe responses that should
* be grouped with this beacon for updates ...
*/
if (!cfg80211_combine_bsses(rdev, new)) {
kfree(new);
goto drop;
}
}
if (rdev->bss_entries >= bss_entries_limit &&
!cfg80211_bss_expire_oldest(rdev)) {
kfree(new);
goto drop;
}
/* This must be before the call to bss_ref_get */
if (tmp->pub.transmitted_bss) {
struct cfg80211_internal_bss *pbss =
container_of(tmp->pub.transmitted_bss,
struct cfg80211_internal_bss,
pub);
new->pub.transmitted_bss = tmp->pub.transmitted_bss;
bss_ref_get(rdev, pbss);
}
list_add_tail(&new->list, &rdev->bss_list);
rdev->bss_entries++;
rb_insert_bss(rdev, new);
found = new;
}
rdev->bss_generation++;
bss_ref_get(rdev, found);
spin_unlock_bh(&rdev->bss_lock);
return found;
drop:
spin_unlock_bh(&rdev->bss_lock);
return NULL;
}
/*
* Update RX channel information based on the available frame payload
* information. This is mainly for the 2.4 GHz band where frames can be received
* from neighboring channels and the Beacon frames use the DSSS Parameter Set
* element to indicate the current (transmitting) channel, but this might also
* be needed on other bands if RX frequency does not match with the actual
* operating channel of a BSS.
*/
static struct ieee80211_channel *
cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
struct ieee80211_channel *channel,
enum nl80211_bss_scan_width scan_width)
{
const u8 *tmp;
u32 freq;
int channel_number = -1;
struct ieee80211_channel *alt_channel;
tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
if (tmp && tmp[1] == 1) {
channel_number = tmp[2];
} else {
tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
channel_number = htop->primary_chan;
}
}
if (channel_number < 0) {
/* No channel information in frame payload */
return channel;
}
freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
alt_channel = ieee80211_get_channel_khz(wiphy, freq);
if (!alt_channel) {
if (channel->band == NL80211_BAND_2GHZ) {
/*
* Better not allow unexpected channels when that could
* be going beyond the 1-11 range (e.g., discovering
* BSS on channel 12 when radio is configured for
* channel 11.
*/
return NULL;
}
/* No match for the payload channel number - ignore it */
return channel;
}
if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
scan_width == NL80211_BSS_CHAN_WIDTH_5) {
/*
* Ignore channel number in 5 and 10 MHz channels where there
* may not be an n:1 or 1:n mapping between frequencies and
* channel numbers.
*/
return channel;
}
/*
* Use the channel determined through the payload channel number
* instead of the RX channel reported by the driver.
*/
if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
return NULL;
return alt_channel;
}
/* Returned bss is reference counted and must be cleaned up appropriately. */
static struct cfg80211_bss *
cfg80211_inform_single_bss_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
enum cfg80211_bss_frame_type ftype,
const u8 *bssid, u64 tsf, u16 capability,
u16 beacon_interval, const u8 *ie, size_t ielen,
struct cfg80211_non_tx_bss *non_tx_data,
gfp_t gfp)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_bss_ies *ies;
struct ieee80211_channel *channel;
struct cfg80211_internal_bss tmp = {}, *res;
int bss_type;
bool signal_valid;
unsigned long ts;
if (WARN_ON(!wiphy))
return NULL;
if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
(data->signal < 0 || data->signal > 100)))
return NULL;
channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
data->scan_width);
if (!channel)
return NULL;
memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
tmp.pub.channel = channel;
tmp.pub.scan_width = data->scan_width;
tmp.pub.signal = data->signal;
tmp.pub.beacon_interval = beacon_interval;
tmp.pub.capability = capability;
tmp.ts_boottime = data->boottime_ns;
if (non_tx_data) {
tmp.pub.transmitted_bss = non_tx_data->tx_bss;
ts = bss_from_pub(non_tx_data->tx_bss)->ts;
tmp.pub.bssid_index = non_tx_data->bssid_index;
tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
} else {
ts = jiffies;
}
/*
* If we do not know here whether the IEs are from a Beacon or Probe
* Response frame, we need to pick one of the options and only use it
* with the driver that does not provide the full Beacon/Probe Response
* frame. Use Beacon frame pointer to avoid indicating that this should
* override the IEs pointer should we have received an earlier
* indication of Probe Response data.
*/
ies = kzalloc(sizeof(*ies) + ielen, gfp);
if (!ies)
return NULL;
ies->len = ielen;
ies->tsf = tsf;
ies->from_beacon = false;
memcpy(ies->data, ie, ielen);
switch (ftype) {
case CFG80211_BSS_FTYPE_BEACON:
ies->from_beacon = true;
/* fall through */
case CFG80211_BSS_FTYPE_UNKNOWN:
rcu_assign_pointer(tmp.pub.beacon_ies, ies);
break;
case CFG80211_BSS_FTYPE_PRESP:
rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
break;
}
rcu_assign_pointer(tmp.pub.ies, ies);
signal_valid = data->chan == channel;
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
if (!res)
return NULL;
if (channel->band == NL80211_BAND_60GHZ) {
bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
regulatory_hint_found_beacon(wiphy, channel, gfp);
} else {
if (res->pub.capability & WLAN_CAPABILITY_ESS)
regulatory_hint_found_beacon(wiphy, channel, gfp);
}
if (non_tx_data) {
/* this is a nontransmitting bss, we need to add it to
* transmitting bss' list if it is not there
*/
if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
&res->pub)) {
if (__cfg80211_unlink_bss(rdev, res))
rdev->bss_generation++;
}
}
trace_cfg80211_return_bss(&res->pub);
/* cfg80211_bss_update gives us a referenced result */
return &res->pub;
}
static const struct element
*cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
const struct element *mbssid_elem,
const struct element *sub_elem)
{
const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
const struct element *next_mbssid;
const struct element *next_sub;
next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
mbssid_end,
ielen - (mbssid_end - ie));
/*
* If is is not the last subelement in current MBSSID IE or there isn't
* a next MBSSID IE - profile is complete.
*/
if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
!next_mbssid)
return NULL;
/* For any length error, just return NULL */
if (next_mbssid->datalen < 4)
return NULL;
next_sub = (void *)&next_mbssid->data[1];
if (next_mbssid->data + next_mbssid->datalen <
next_sub->data + next_sub->datalen)
return NULL;
if (next_sub->id != 0 || next_sub->datalen < 2)
return NULL;
/*
* Check if the first element in the next sub element is a start
* of a new profile
*/
return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
NULL : next_mbssid;
}
size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
const struct element *mbssid_elem,
const struct element *sub_elem,
u8 *merged_ie, size_t max_copy_len)
{
size_t copied_len = sub_elem->datalen;
const struct element *next_mbssid;
if (sub_elem->datalen > max_copy_len)
return 0;
memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
mbssid_elem,
sub_elem))) {
const struct element *next_sub = (void *)&next_mbssid->data[1];
if (copied_len + next_sub->datalen > max_copy_len)
break;
memcpy(merged_ie + copied_len, next_sub->data,
next_sub->datalen);
copied_len += next_sub->datalen;
}
return copied_len;
}
EXPORT_SYMBOL(cfg80211_merge_profile);
static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
enum cfg80211_bss_frame_type ftype,
const u8 *bssid, u64 tsf,
u16 beacon_interval, const u8 *ie,
size_t ielen,
struct cfg80211_non_tx_bss *non_tx_data,
gfp_t gfp)
{
const u8 *mbssid_index_ie;
const struct element *elem, *sub;
size_t new_ie_len;
u8 new_bssid[ETH_ALEN];
u8 *new_ie, *profile;
u64 seen_indices = 0;
u16 capability;
struct cfg80211_bss *bss;
if (!non_tx_data)
return;
if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
return;
if (!wiphy->support_mbssid)
return;
if (wiphy->support_only_he_mbssid &&
!cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
return;
new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
if (!new_ie)
return;
profile = kmalloc(ielen, gfp);
if (!profile)
goto out;
for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
if (elem->datalen < 4)
continue;
for_each_element(sub, elem->data + 1, elem->datalen - 1) {
u8 profile_len;
if (sub->id != 0 || sub->datalen < 4) {
/* not a valid BSS profile */
continue;
}
if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
sub->data[1] != 2) {
/* The first element within the Nontransmitted
* BSSID Profile is not the Nontransmitted
* BSSID Capability element.
*/
continue;
}
memset(profile, 0, ielen);
profile_len = cfg80211_merge_profile(ie, ielen,
elem,
sub,
profile,
ielen);
/* found a Nontransmitted BSSID Profile */
mbssid_index_ie = cfg80211_find_ie
(WLAN_EID_MULTI_BSSID_IDX,
profile, profile_len);
if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
mbssid_index_ie[2] == 0 ||
mbssid_index_ie[2] > 46) {
/* No valid Multiple BSSID-Index element */
continue;
}
if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
/* We don't support legacy split of a profile */
net_dbg_ratelimited("Partial info for BSSID index %d\n",
mbssid_index_ie[2]);
seen_indices |= BIT_ULL(mbssid_index_ie[2]);
non_tx_data->bssid_index = mbssid_index_ie[2];
non_tx_data->max_bssid_indicator = elem->data[0];
cfg80211_gen_new_bssid(bssid,
non_tx_data->max_bssid_indicator,
non_tx_data->bssid_index,
new_bssid);
memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
new_ie_len = cfg80211_gen_new_ie(ie, ielen,
profile,
profile_len, new_ie,
gfp);
if (!new_ie_len)
continue;
capability = get_unaligned_le16(profile + 2);
bss = cfg80211_inform_single_bss_data(wiphy, data,
ftype,
new_bssid, tsf,
capability,
beacon_interval,
new_ie,
new_ie_len,
non_tx_data,
gfp);
if (!bss)
break;
cfg80211_put_bss(wiphy, bss);
}
}
out:
kfree(new_ie);
kfree(profile);
}
struct cfg80211_bss *
cfg80211_inform_bss_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
enum cfg80211_bss_frame_type ftype,
const u8 *bssid, u64 tsf, u16 capability,
u16 beacon_interval, const u8 *ie, size_t ielen,
gfp_t gfp)
{
struct cfg80211_bss *res;
struct cfg80211_non_tx_bss non_tx_data;
res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
capability, beacon_interval, ie,
ielen, NULL, gfp);
if (!res)
return NULL;
non_tx_data.tx_bss = res;
cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
beacon_interval, ie, ielen, &non_tx_data,
gfp);
return res;
}
EXPORT_SYMBOL(cfg80211_inform_bss_data);
static void
cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
struct ieee80211_mgmt *mgmt, size_t len,
struct cfg80211_non_tx_bss *non_tx_data,
gfp_t gfp)
{
enum cfg80211_bss_frame_type ftype;
const u8 *ie = mgmt->u.probe_resp.variable;
size_t ielen = len - offsetof(struct ieee80211_mgmt,
u.probe_resp.variable);
ftype = ieee80211_is_beacon(mgmt->frame_control) ?
CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
le64_to_cpu(mgmt->u.probe_resp.timestamp),
le16_to_cpu(mgmt->u.probe_resp.beacon_int),
ie, ielen, non_tx_data, gfp);
}
static void
cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
struct cfg80211_bss *nontrans_bss,
struct ieee80211_mgmt *mgmt, size_t len)
{
u8 *ie, *new_ie, *pos;
const u8 *nontrans_ssid, *trans_ssid, *mbssid;
size_t ielen = len - offsetof(struct ieee80211_mgmt,
u.probe_resp.variable);
size_t new_ie_len;
struct cfg80211_bss_ies *new_ies;
const struct cfg80211_bss_ies *old;
u8 cpy_len;
lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
ie = mgmt->u.probe_resp.variable;
new_ie_len = ielen;
trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
if (!trans_ssid)
return;
new_ie_len -= trans_ssid[1];
mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
/*
* It's not valid to have the MBSSID element before SSID
* ignore if that happens - the code below assumes it is
* after (while copying things inbetween).
*/
if (!mbssid || mbssid < trans_ssid)
return;
new_ie_len -= mbssid[1];
nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
if (!nontrans_ssid)
return;
new_ie_len += nontrans_ssid[1];
/* generate new ie for nontrans BSS
* 1. replace SSID with nontrans BSS' SSID
* 2. skip MBSSID IE
*/
new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
if (!new_ie)
return;
new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
if (!new_ies)
goto out_free;
pos = new_ie;
/* copy the nontransmitted SSID */
cpy_len = nontrans_ssid[1] + 2;
memcpy(pos, nontrans_ssid, cpy_len);
pos += cpy_len;
/* copy the IEs between SSID and MBSSID */
cpy_len = trans_ssid[1] + 2;
memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
pos += (mbssid - (trans_ssid + cpy_len));
/* copy the IEs after MBSSID */
cpy_len = mbssid[1] + 2;
memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
/* update ie */
new_ies->len = new_ie_len;
new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
memcpy(new_ies->data, new_ie, new_ie_len);
if (ieee80211_is_probe_resp(mgmt->frame_control)) {
old = rcu_access_pointer(nontrans_bss->proberesp_ies);
rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
rcu_assign_pointer(nontrans_bss->ies, new_ies);
if (old)
kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
} else {
old = rcu_access_pointer(nontrans_bss->beacon_ies);
rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
rcu_assign_pointer(nontrans_bss->ies, new_ies);
if (old)
kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
}
out_free:
kfree(new_ie);
}
/* cfg80211_inform_bss_width_frame helper */
static struct cfg80211_bss *
cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
struct ieee80211_mgmt *mgmt, size_t len,
gfp_t gfp)
{
struct cfg80211_internal_bss tmp = {}, *res;
struct cfg80211_bss_ies *ies;
struct ieee80211_channel *channel;
bool signal_valid;
size_t ielen = len - offsetof(struct ieee80211_mgmt,
u.probe_resp.variable);
int bss_type;
BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
offsetof(struct ieee80211_mgmt, u.beacon.variable));
trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
if (WARN_ON(!mgmt))
return NULL;
if (WARN_ON(!wiphy))
return NULL;
if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
(data->signal < 0 || data->signal > 100)))
return NULL;
if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
return NULL;
channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
ielen, data->chan, data->scan_width);
if (!channel)
return NULL;
ies = kzalloc(sizeof(*ies) + ielen, gfp);
if (!ies)
return NULL;
ies->len = ielen;
ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
if (ieee80211_is_probe_resp(mgmt->frame_control))
rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
else
rcu_assign_pointer(tmp.pub.beacon_ies, ies);
rcu_assign_pointer(tmp.pub.ies, ies);
memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
tmp.pub.channel = channel;
tmp.pub.scan_width = data->scan_width;
tmp.pub.signal = data->signal;
tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
tmp.ts_boottime = data->boottime_ns;
tmp.parent_tsf = data->parent_tsf;
tmp.pub.chains = data->chains;
memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
signal_valid = data->chan == channel;
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
jiffies);
if (!res)
return NULL;
if (channel->band == NL80211_BAND_60GHZ) {
bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
regulatory_hint_found_beacon(wiphy, channel, gfp);
} else {
if (res->pub.capability & WLAN_CAPABILITY_ESS)
regulatory_hint_found_beacon(wiphy, channel, gfp);
}
trace_cfg80211_return_bss(&res->pub);
/* cfg80211_bss_update gives us a referenced result */
return &res->pub;
}
struct cfg80211_bss *
cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
struct ieee80211_mgmt *mgmt, size_t len,
gfp_t gfp)
{
struct cfg80211_bss *res, *tmp_bss;
const u8 *ie = mgmt->u.probe_resp.variable;
const struct cfg80211_bss_ies *ies1, *ies2;
size_t ielen = len - offsetof(struct ieee80211_mgmt,
u.probe_resp.variable);
struct cfg80211_non_tx_bss non_tx_data;
res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
len, gfp);
if (!res || !wiphy->support_mbssid ||
!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
return res;
if (wiphy->support_only_he_mbssid &&
!cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
return res;
non_tx_data.tx_bss = res;
/* process each non-transmitting bss */
cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
&non_tx_data, gfp);
spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
/* check if the res has other nontransmitting bss which is not
* in MBSSID IE
*/
ies1 = rcu_access_pointer(res->ies);
/* go through nontrans_list, if the timestamp of the BSS is
* earlier than the timestamp of the transmitting BSS then
* update it
*/
list_for_each_entry(tmp_bss, &res->nontrans_list,
nontrans_list) {
ies2 = rcu_access_pointer(tmp_bss->ies);
if (ies2->tsf < ies1->tsf)
cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
mgmt, len);
}
spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
return res;
}
EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *bss;
if (!pub)
return;
bss = container_of(pub, struct cfg80211_internal_bss, pub);
spin_lock_bh(&rdev->bss_lock);
bss_ref_get(rdev, bss);
spin_unlock_bh(&rdev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_ref_bss);
void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *bss;
if (!pub)
return;
bss = container_of(pub, struct cfg80211_internal_bss, pub);
spin_lock_bh(&rdev->bss_lock);
bss_ref_put(rdev, bss);
spin_unlock_bh(&rdev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_put_bss);
void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *bss, *tmp1;
struct cfg80211_bss *nontrans_bss, *tmp;
if (WARN_ON(!pub))
return;
bss = container_of(pub, struct cfg80211_internal_bss, pub);
spin_lock_bh(&rdev->bss_lock);
if (list_empty(&bss->list))
goto out;
list_for_each_entry_safe(nontrans_bss, tmp,
&pub->nontrans_list,
nontrans_list) {
tmp1 = container_of(nontrans_bss,
struct cfg80211_internal_bss, pub);
if (__cfg80211_unlink_bss(rdev, tmp1))
rdev->bss_generation++;
}
if (__cfg80211_unlink_bss(rdev, bss))
rdev->bss_generation++;
out:
spin_unlock_bh(&rdev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_unlink_bss);
void cfg80211_bss_iter(struct wiphy *wiphy,
struct cfg80211_chan_def *chandef,
void (*iter)(struct wiphy *wiphy,
struct cfg80211_bss *bss,
void *data),
void *iter_data)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *bss;
spin_lock_bh(&rdev->bss_lock);
list_for_each_entry(bss, &rdev->bss_list, list) {
if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel))
iter(wiphy, &bss->pub, iter_data);
}
spin_unlock_bh(&rdev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_bss_iter);
void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
struct ieee80211_channel *chan)
{
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
struct cfg80211_internal_bss *cbss = wdev->current_bss;
struct cfg80211_internal_bss *new = NULL;
struct cfg80211_internal_bss *bss;
struct cfg80211_bss *nontrans_bss;
struct cfg80211_bss *tmp;
spin_lock_bh(&rdev->bss_lock);
/*
* Some APs use CSA also for bandwidth changes, i.e., without actually
* changing the control channel, so no need to update in such a case.
*/
if (cbss->pub.channel == chan)
goto done;
/* use transmitting bss */
if (cbss->pub.transmitted_bss)
cbss = container_of(cbss->pub.transmitted_bss,
struct cfg80211_internal_bss,
pub);
cbss->pub.channel = chan;
list_for_each_entry(bss, &rdev->bss_list, list) {
if (!cfg80211_bss_type_match(bss->pub.capability,
bss->pub.channel->band,
wdev->conn_bss_type))
continue;
if (bss == cbss)
continue;
if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
new = bss;
break;
}
}
if (new) {
/* to save time, update IEs for transmitting bss only */
if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
new->pub.proberesp_ies = NULL;
new->pub.beacon_ies = NULL;
}
list_for_each_entry_safe(nontrans_bss, tmp,
&new->pub.nontrans_list,
nontrans_list) {
bss = container_of(nontrans_bss,
struct cfg80211_internal_bss, pub);
if (__cfg80211_unlink_bss(rdev, bss))
rdev->bss_generation++;
}
WARN_ON(atomic_read(&new->hold));
if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
rdev->bss_generation++;
}
rb_erase(&cbss->rbn, &rdev->bss_tree);
rb_insert_bss(rdev, cbss);
rdev->bss_generation++;
list_for_each_entry_safe(nontrans_bss, tmp,
&cbss->pub.nontrans_list,
nontrans_list) {
bss = container_of(nontrans_bss,
struct cfg80211_internal_bss, pub);
bss->pub.channel = chan;
rb_erase(&bss->rbn, &rdev->bss_tree);
rb_insert_bss(rdev, bss);
rdev->bss_generation++;
}
done:
spin_unlock_bh(&rdev->bss_lock);
}
#ifdef CONFIG_CFG80211_WEXT
static struct cfg80211_registered_device *
cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
{
struct cfg80211_registered_device *rdev;
struct net_device *dev;
ASSERT_RTNL();
dev = dev_get_by_index(net, ifindex);
if (!dev)
return ERR_PTR(-ENODEV);
if (dev->ieee80211_ptr)
rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
else
rdev = ERR_PTR(-ENODEV);
dev_put(dev);
return rdev;
}
int cfg80211_wext_siwscan(struct net_device *dev,
struct iw_request_info *info,
union iwreq_data *wrqu, char *extra)
{
struct cfg80211_registered_device *rdev;
struct wiphy *wiphy;
struct iw_scan_req *wreq = NULL;
struct cfg80211_scan_request *creq = NULL;
int i, err, n_channels = 0;
enum nl80211_band band;
if (!netif_running(dev))
return -ENETDOWN;
if (wrqu->data.length == sizeof(struct iw_scan_req))
wreq = (struct iw_scan_req *)extra;
rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
if (IS_ERR(rdev))
return PTR_ERR(rdev);
if (rdev->scan_req || rdev->scan_msg) {
err = -EBUSY;
goto out;
}
wiphy = &rdev->wiphy;
/* Determine number of channels, needed to allocate creq */
if (wreq && wreq->num_channels)
n_channels = wreq->num_channels;
else
n_channels = ieee80211_get_num_supported_channels(wiphy);
creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
n_channels * sizeof(void *),
GFP_ATOMIC);
if (!creq) {
err = -ENOMEM;
goto out;
}
creq->wiphy = wiphy;
creq->wdev = dev->ieee80211_ptr;
/* SSIDs come after channels */
creq->ssids = (void *)&creq->channels[n_channels];
creq->n_channels = n_channels;
creq->n_ssids = 1;
creq->scan_start = jiffies;
/* translate "Scan on frequencies" request */
i = 0;
for (band = 0; band < NUM_NL80211_BANDS; band++) {
int j;
if (!wiphy->bands[band])
continue;
for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
/* ignore disabled channels */
if (wiphy->bands[band]->channels[j].flags &
IEEE80211_CHAN_DISABLED)
continue;
/* If we have a wireless request structure and the
* wireless request specifies frequencies, then search
* for the matching hardware channel.
*/
if (wreq && wreq->num_channels) {
int k;
int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
for (k = 0; k < wreq->num_channels; k++) {
struct iw_freq *freq =
&wreq->channel_list[k];
int wext_freq =
cfg80211_wext_freq(freq);
if (wext_freq == wiphy_freq)
goto wext_freq_found;
}
goto wext_freq_not_found;
}
wext_freq_found:
creq->channels[i] = &wiphy->bands[band]->channels[j];
i++;
wext_freq_not_found: ;
}
}
/* No channels found? */
if (!i) {
err = -EINVAL;
goto out;
}
/* Set real number of channels specified in creq->channels[] */
creq->n_channels = i;
/* translate "Scan for SSID" request */
if (wreq) {
if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
err = -EINVAL;
goto out;
}
memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
creq->ssids[0].ssid_len = wreq->essid_len;
}
if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
creq->n_ssids = 0;
}
for (i = 0; i < NUM_NL80211_BANDS; i++)
if (wiphy->bands[i])
creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
eth_broadcast_addr(creq->bssid);
rdev->scan_req = creq;
err = rdev_scan(rdev, creq);
if (err) {
rdev->scan_req = NULL;
/* creq will be freed below */
} else {
nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
/* creq now owned by driver */
creq = NULL;
dev_hold(dev);
}
out:
kfree(creq);
return err;
}
EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
static char *ieee80211_scan_add_ies(struct iw_request_info *info,
const struct cfg80211_bss_ies *ies,
char *current_ev, char *end_buf)
{
const u8 *pos, *end, *next;
struct iw_event iwe;
if (!ies)
return current_ev;
/*
* If needed, fragment the IEs buffer (at IE boundaries) into short
* enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
*/
pos = ies->data;
end = pos + ies->len;
while (end - pos > IW_GENERIC_IE_MAX) {
next = pos + 2 + pos[1];
while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
next = next + 2 + next[1];
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVGENIE;
iwe.u.data.length = next - pos;
current_ev = iwe_stream_add_point_check(info, current_ev,
end_buf, &iwe,
(void *)pos);
if (IS_ERR(current_ev))
return current_ev;
pos = next;
}
if (end > pos) {
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVGENIE;
iwe.u.data.length = end - pos;
current_ev = iwe_stream_add_point_check(info, current_ev,
end_buf, &iwe,
(void *)pos);
if (IS_ERR(current_ev))
return current_ev;
}
return current_ev;
}
static char *
ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
struct cfg80211_internal_bss *bss, char *current_ev,
char *end_buf)
{
const struct cfg80211_bss_ies *ies;
struct iw_event iwe;
const u8 *ie;
u8 buf[50];
u8 *cfg, *p, *tmp;
int rem, i, sig;
bool ismesh = false;
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWAP;
iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
IW_EV_ADDR_LEN);
if (IS_ERR(current_ev))
return current_ev;
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWFREQ;
iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
iwe.u.freq.e = 0;
current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
IW_EV_FREQ_LEN);
if (IS_ERR(current_ev))
return current_ev;
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWFREQ;
iwe.u.freq.m = bss->pub.channel->center_freq;
iwe.u.freq.e = 6;
current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
IW_EV_FREQ_LEN);
if (IS_ERR(current_ev))
return current_ev;
if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVQUAL;
iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
IW_QUAL_NOISE_INVALID |
IW_QUAL_QUAL_UPDATED;
switch (wiphy->signal_type) {
case CFG80211_SIGNAL_TYPE_MBM:
sig = bss->pub.signal / 100;
iwe.u.qual.level = sig;
iwe.u.qual.updated |= IW_QUAL_DBM;
if (sig < -110) /* rather bad */
sig = -110;
else if (sig > -40) /* perfect */
sig = -40;
/* will give a range of 0 .. 70 */
iwe.u.qual.qual = sig + 110;
break;
case CFG80211_SIGNAL_TYPE_UNSPEC:
iwe.u.qual.level = bss->pub.signal;
/* will give range 0 .. 100 */
iwe.u.qual.qual = bss->pub.signal;
break;
default:
/* not reached */
break;
}
current_ev = iwe_stream_add_event_check(info, current_ev,
end_buf, &iwe,
IW_EV_QUAL_LEN);
if (IS_ERR(current_ev))
return current_ev;
}
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWENCODE;
if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
else
iwe.u.data.flags = IW_ENCODE_DISABLED;
iwe.u.data.length = 0;
current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
&iwe, "");
if (IS_ERR(current_ev))
return current_ev;
rcu_read_lock();
ies = rcu_dereference(bss->pub.ies);
rem = ies->len;
ie = ies->data;
while (rem >= 2) {
/* invalid data */
if (ie[1] > rem - 2)
break;
switch (ie[0]) {
case WLAN_EID_SSID:
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWESSID;
iwe.u.data.length = ie[1];
iwe.u.data.flags = 1;
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf, &iwe,
(u8 *)ie + 2);
if (IS_ERR(current_ev))
goto unlock;
break;
case WLAN_EID_MESH_ID:
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWESSID;
iwe.u.data.length = ie[1];
iwe.u.data.flags = 1;
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf, &iwe,
(u8 *)ie + 2);
if (IS_ERR(current_ev))
goto unlock;
break;
case WLAN_EID_MESH_CONFIG:
ismesh = true;
if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
break;
cfg = (u8 *)ie + 2;
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVCUSTOM;
sprintf(buf, "Mesh Network Path Selection Protocol ID: "
"0x%02X", cfg[0]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Path Selection Metric ID: 0x%02X",
cfg[1]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Congestion Control Mode ID: 0x%02X",
cfg[2]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info,
current_ev,
end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
break;
case WLAN_EID_SUPP_RATES:
case WLAN_EID_EXT_SUPP_RATES:
/* display all supported rates in readable format */
p = current_ev + iwe_stream_lcp_len(info);
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWRATE;
/* Those two flags are ignored... */
iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
for (i = 0; i < ie[1]; i++) {
iwe.u.bitrate.value =
((ie[i + 2] & 0x7f) * 500000);
tmp = p;
p = iwe_stream_add_value(info, current_ev, p,
end_buf, &iwe,
IW_EV_PARAM_LEN);
if (p == tmp) {
current_ev = ERR_PTR(-E2BIG);
goto unlock;
}
}
current_ev = p;
break;
}
rem -= ie[1] + 2;
ie += ie[1] + 2;
}
if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
ismesh) {
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = SIOCGIWMODE;
if (ismesh)
iwe.u.mode = IW_MODE_MESH;
else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
iwe.u.mode = IW_MODE_MASTER;
else
iwe.u.mode = IW_MODE_ADHOC;
current_ev = iwe_stream_add_event_check(info, current_ev,
end_buf, &iwe,
IW_EV_UINT_LEN);
if (IS_ERR(current_ev))
goto unlock;
}
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVCUSTOM;
sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
&iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVCUSTOM;
sprintf(buf, " Last beacon: %ums ago",
elapsed_jiffies_msecs(bss->ts));
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point_check(info, current_ev,
end_buf, &iwe, buf);
if (IS_ERR(current_ev))
goto unlock;
current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
unlock:
rcu_read_unlock();
return current_ev;
}
static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
struct iw_request_info *info,
char *buf, size_t len)
{
char *current_ev = buf;
char *end_buf = buf + len;
struct cfg80211_internal_bss *bss;
int err = 0;
spin_lock_bh(&rdev->bss_lock);
cfg80211_bss_expire(rdev);
list_for_each_entry(bss, &rdev->bss_list, list) {
if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
err = -E2BIG;
break;
}
current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
current_ev, end_buf);
if (IS_ERR(current_ev)) {
err = PTR_ERR(current_ev);
break;
}
}
spin_unlock_bh(&rdev->bss_lock);
if (err)
return err;
return current_ev - buf;
}
int cfg80211_wext_giwscan(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *extra)
{
struct cfg80211_registered_device *rdev;
int res;
if (!netif_running(dev))
return -ENETDOWN;
rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
if (IS_ERR(rdev))
return PTR_ERR(rdev);
if (rdev->scan_req || rdev->scan_msg)
return -EAGAIN;
res = ieee80211_scan_results(rdev, info, extra, data->length);
data->length = 0;
if (res >= 0) {
data->length = res;
res = 0;
}
return res;
}
EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
#endif
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