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-rw-r--r--net/wireless/scan.c630
1 files changed, 335 insertions, 295 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 45f1618c8e23..674aadca0079 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -19,55 +19,142 @@
#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.
+ */
+
#define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
-static void bss_release(struct kref *ref)
+static void bss_free(struct cfg80211_internal_bss *bss)
{
struct cfg80211_bss_ies *ies;
- struct cfg80211_internal_bss *bss;
-
- bss = container_of(ref, struct cfg80211_internal_bss, ref);
if (WARN_ON(atomic_read(&bss->hold)))
return;
- if (bss->pub.free_priv)
- bss->pub.free_priv(&bss->pub);
-
ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
- if (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);
}
-/* must hold dev->bss_lock! */
-static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
+static inline void bss_ref_get(struct cfg80211_registered_device *dev,
+ struct cfg80211_internal_bss *bss)
+{
+ lockdep_assert_held(&dev->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++;
+ }
+}
+
+static inline void bss_ref_put(struct cfg80211_registered_device *dev,
+ struct cfg80211_internal_bss *bss)
+{
+ lockdep_assert_held(&dev->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);
+ }
+ bss->refcount--;
+ if (bss->refcount == 0)
+ bss_free(bss);
+}
+
+static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
struct cfg80211_internal_bss *bss)
{
+ lockdep_assert_held(&dev->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);
rb_erase(&bss->rbn, &dev->bss_tree);
- kref_put(&bss->ref, bss_release);
+ bss_ref_put(dev, bss);
+ return true;
}
-/* must hold dev->bss_lock! */
static void __cfg80211_bss_expire(struct cfg80211_registered_device *dev,
unsigned long expire_time)
{
struct cfg80211_internal_bss *bss, *tmp;
bool expired = false;
+ lockdep_assert_held(&dev->bss_lock);
+
list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
if (atomic_read(&bss->hold))
continue;
if (!time_after(expire_time, bss->ts))
continue;
- __cfg80211_unlink_bss(dev, bss);
- expired = true;
+ if (__cfg80211_unlink_bss(dev, bss))
+ expired = true;
}
if (expired)
@@ -234,15 +321,16 @@ int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
return 0;
}
-/* must hold dev->bss_lock! */
void cfg80211_bss_age(struct cfg80211_registered_device *dev,
unsigned long age_secs)
{
struct cfg80211_internal_bss *bss;
unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
+ spin_lock_bh(&dev->bss_lock);
list_for_each_entry(bss, &dev->bss_list, list)
bss->ts -= age_jiffies;
+ spin_unlock_bh(&dev->bss_lock);
}
void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
@@ -277,40 +365,24 @@ const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
if (!pos)
return NULL;
- if (end - pos < sizeof(*ie))
- return NULL;
-
ie = (struct ieee80211_vendor_ie *)pos;
+
+ /* make sure we can access ie->len */
+ BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
+
+ if (ie->len < sizeof(*ie))
+ goto cont;
+
ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
if (ie_oui == oui && ie->oui_type == oui_type)
return pos;
-
+cont:
pos += 2 + ie->len;
}
return NULL;
}
EXPORT_SYMBOL(cfg80211_find_vendor_ie);
-static int cmp_ies(u8 num, const u8 *ies1, int len1, const u8 *ies2, int len2)
-{
- const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
- const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
-
- /* equal if both missing */
- if (!ie1 && !ie2)
- return 0;
- /* sort missing IE before (left of) present IE */
- if (!ie1)
- return -1;
- if (!ie2)
- return 1;
-
- /* 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]);
-}
-
static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
const u8 *ssid, size_t ssid_len)
{
@@ -334,109 +406,30 @@ static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
return memcmp(ssidie + 2, ssid, ssid_len) == 0;
}
-static bool is_mesh_bss(struct cfg80211_bss *a)
-{
- const struct cfg80211_bss_ies *ies;
- const u8 *ie;
-
- if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
- return false;
-
- ies = rcu_access_pointer(a->ies);
- if (!ies)
- return false;
-
- ie = cfg80211_find_ie(WLAN_EID_MESH_ID, ies->data, ies->len);
- if (!ie)
- return false;
-
- ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, ies->data, ies->len);
- if (!ie)
- return false;
-
- return true;
-}
-
-static bool is_mesh(struct cfg80211_bss *a,
- const u8 *meshid, size_t meshidlen,
- const u8 *meshcfg)
-{
- const struct cfg80211_bss_ies *ies;
- const u8 *ie;
-
- if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
- return false;
-
- ies = rcu_access_pointer(a->ies);
- if (!ies)
- return false;
-
- ie = cfg80211_find_ie(WLAN_EID_MESH_ID, ies->data, ies->len);
- if (!ie)
- return false;
- if (ie[1] != meshidlen)
- return false;
- if (memcmp(ie + 2, meshid, meshidlen))
- return false;
-
- ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, ies->data, ies->len);
- if (!ie)
- return false;
- if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
- return false;
-
- /*
- * Ignore mesh capability (last two bytes of the IE) when
- * comparing since that may differ between stations taking
- * part in the same mesh.
- */
- return memcmp(ie + 2, meshcfg,
- sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
-}
+/**
+ * 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_core(struct cfg80211_bss *a, struct cfg80211_bss *b)
+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;
- int r;
+ 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;
- if (is_mesh_bss(a) && is_mesh_bss(b)) {
- a_ies = rcu_access_pointer(a->ies);
- if (!a_ies)
- return -1;
- b_ies = rcu_access_pointer(b->ies);
- if (!b_ies)
- return 1;
-
- r = cmp_ies(WLAN_EID_MESH_ID,
- a_ies->data, a_ies->len,
- b_ies->data, b_ies->len);
- if (r)
- return r;
- return cmp_ies(WLAN_EID_MESH_CONFIG,
- a_ies->data, a_ies->len,
- b_ies->data, b_ies->len);
- }
-
- /*
- * we can't use compare_ether_addr here since we need a < > operator.
- * The binary return value of compare_ether_addr isn't enough
- */
- return memcmp(a->bssid, b->bssid, sizeof(a->bssid));
-}
-
-static int cmp_bss(struct cfg80211_bss *a,
- struct cfg80211_bss *b)
-{
- const struct cfg80211_bss_ies *a_ies, *b_ies;
- int r;
-
- r = cmp_bss_core(a, b);
- if (r)
- return r;
-
a_ies = rcu_access_pointer(a->ies);
if (!a_ies)
return -1;
@@ -444,42 +437,51 @@ static int cmp_bss(struct cfg80211_bss *a,
if (!b_ies)
return 1;
- return cmp_ies(WLAN_EID_SSID,
- a_ies->data, a_ies->len,
- b_ies->data, b_ies->len);
-}
-
-static int cmp_hidden_bss(struct cfg80211_bss *a, struct cfg80211_bss *b)
-{
- const struct cfg80211_bss_ies *a_ies, *b_ies;
- const u8 *ie1;
- const u8 *ie2;
- int i;
- int r;
+ 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 = cmp_bss_core(a, b);
+ /*
+ * we can't use compare_ether_addr here since we need a < > operator.
+ * The binary return value of compare_ether_addr isn't enough
+ */
+ r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
if (r)
return r;
- a_ies = rcu_access_pointer(a->ies);
- if (!a_ies)
- return -1;
- b_ies = rcu_access_pointer(b->ies);
- if (!b_ies)
- return 1;
-
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;
+
/*
- * Key comparator must use same algorithm in any rb-tree
- * search function (order is important), otherwise ordering
- * of items in the tree is broken and search gives incorrect
- * results. This code uses same order as cmp_ies() does.
- *
- * Note that due to the differring behaviour with hidden SSIDs
- * this function only works when "b" is the tree element and
- * "a" is the key we're looking for.
+ * 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 */
@@ -488,24 +490,36 @@ static int cmp_hidden_bss(struct cfg80211_bss *a, struct cfg80211_bss *b)
if (!ie2)
return 1;
- /* zero-size SSID is used as an indication of the hidden bss */
- if (!ie2[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;
-
- /* sort by length first, then by contents */
- if (ie1[1] != ie2[1])
- return ie2[1] - ie1[1];
-
- /*
- * zeroed SSID ie is another indication of a hidden bss;
- * if it isn't zeroed just return the regular sort value
- * to find the next candidate
- */
- for (i = 0; i < ie2[1]; i++)
- if (ie2[i + 2])
- return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
-
- return 0;
+ }
}
struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
@@ -534,7 +548,7 @@ struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
continue;
if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
res = bss;
- kref_get(&res->ref);
+ bss_ref_get(dev, res);
break;
}
}
@@ -547,34 +561,6 @@ struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
}
EXPORT_SYMBOL(cfg80211_get_bss);
-struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
- struct ieee80211_channel *channel,
- const u8 *meshid, size_t meshidlen,
- const u8 *meshcfg)
-{
- struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
- struct cfg80211_internal_bss *bss, *res = NULL;
-
- spin_lock_bh(&dev->bss_lock);
-
- list_for_each_entry(bss, &dev->bss_list, list) {
- if (channel && bss->pub.channel != channel)
- continue;
- if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
- res = bss;
- kref_get(&res->ref);
- break;
- }
- }
-
- spin_unlock_bh(&dev->bss_lock);
- if (!res)
- return NULL;
- return &res->pub;
-}
-EXPORT_SYMBOL(cfg80211_get_mesh);
-
-
static void rb_insert_bss(struct cfg80211_registered_device *dev,
struct cfg80211_internal_bss *bss)
{
@@ -587,7 +573,7 @@ static void rb_insert_bss(struct cfg80211_registered_device *dev,
parent = *p;
tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
- cmp = cmp_bss(&bss->pub, &tbss->pub);
+ cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
if (WARN_ON(!cmp)) {
/* will sort of leak this BSS */
@@ -606,7 +592,8 @@ static void rb_insert_bss(struct cfg80211_registered_device *dev,
static struct cfg80211_internal_bss *
rb_find_bss(struct cfg80211_registered_device *dev,
- struct cfg80211_internal_bss *res)
+ struct cfg80211_internal_bss *res,
+ enum bss_compare_mode mode)
{
struct rb_node *n = dev->bss_tree.rb_node;
struct cfg80211_internal_bss *bss;
@@ -614,7 +601,7 @@ rb_find_bss(struct cfg80211_registered_device *dev,
while (n) {
bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
- r = cmp_bss(&res->pub, &bss->pub);
+ r = cmp_bss(&res->pub, &bss->pub, mode);
if (r == 0)
return bss;
@@ -627,46 +614,67 @@ rb_find_bss(struct cfg80211_registered_device *dev,
return NULL;
}
-static struct cfg80211_internal_bss *
-rb_find_hidden_bss(struct cfg80211_registered_device *dev,
- struct cfg80211_internal_bss *res)
+static bool cfg80211_combine_bsses(struct cfg80211_registered_device *dev,
+ struct cfg80211_internal_bss *new)
{
- struct rb_node *n = dev->bss_tree.rb_node;
+ const struct cfg80211_bss_ies *ies;
struct cfg80211_internal_bss *bss;
- int r;
+ const u8 *ie;
+ int i, ssidlen;
+ u8 fold = 0;
- while (n) {
- bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
- r = cmp_hidden_bss(&res->pub, &bss->pub);
+ ies = rcu_access_pointer(new->pub.beacon_ies);
+ if (WARN_ON(!ies))
+ return false;
- if (r == 0)
- return bss;
- else if (r < 0)
- n = n->rb_left;
- else
- n = n->rb_right;
+ ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
+ if (!ie) {
+ /* nothing to do */
+ return true;
}
- return NULL;
-}
+ ssidlen = ie[1];
+ for (i = 0; i < ssidlen; i++)
+ fold |= ie[2 + i];
-static void
-copy_hidden_ies(struct cfg80211_internal_bss *res,
- struct cfg80211_internal_bss *hidden)
-{
- const struct cfg80211_bss_ies *ies;
+ if (fold) {
+ /* not a hidden SSID */
+ return true;
+ }
- if (rcu_access_pointer(res->pub.beacon_ies))
- return;
+ /* This is the bad part ... */
- ies = rcu_access_pointer(hidden->pub.beacon_ies);
- if (WARN_ON(!ies))
- return;
+ list_for_each_entry(bss, &dev->bss_list, list) {
+ if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
+ continue;
+ if (bss->pub.channel != new->pub.channel)
+ 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;
+ /* that would be odd ... */
+ if (bss->pub.beacon_ies)
+ 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);
+ }
- ies = kmemdup(ies, sizeof(*ies) + ies->len, GFP_ATOMIC);
- if (unlikely(!ies))
- return;
- rcu_assign_pointer(res->pub.beacon_ies, ies);
+ return true;
}
static struct cfg80211_internal_bss *
@@ -687,11 +695,10 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
return NULL;
}
- found = rb_find_bss(dev, tmp);
+ found = rb_find_bss(dev, tmp, BSS_CMP_REGULAR);
if (found) {
found->pub.beacon_interval = tmp->pub.beacon_interval;
- found->pub.tsf = tmp->pub.tsf;
found->pub.signal = tmp->pub.signal;
found->pub.capability = tmp->pub.capability;
found->ts = tmp->ts;
@@ -711,19 +718,45 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
kfree_rcu((struct cfg80211_bss_ies *)old,
rcu_head);
} else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
- const struct cfg80211_bss_ies *old, *ies;
+ const struct cfg80211_bss_ies *old;
+ struct cfg80211_internal_bss *bss;
+
+ if (found->pub.hidden_beacon_bss &&
+ !list_empty(&found->hidden_list)) {
+ /*
+ * The found BSS struct is one of the probe
+ * response members of a group, but we're
+ * receiving a beacon (beacon_ies in the tmp
+ * 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.
+ */
+ goto drop;
+ }
old = rcu_access_pointer(found->pub.beacon_ies);
- ies = rcu_access_pointer(found->pub.ies);
rcu_assign_pointer(found->pub.beacon_ies,
tmp->pub.beacon_ies);
/* Override IEs if they were from a beacon before */
- if (old == ies)
+ if (old == rcu_access_pointer(found->pub.ies))
rcu_assign_pointer(found->pub.ies,
tmp->pub.beacon_ies);
+ /* Assign beacon IEs to all sub entries */
+ list_for_each_entry(bss, &found->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,
+ tmp->pub.beacon_ies);
+ }
+
if (old)
kfree_rcu((struct cfg80211_bss_ies *)old,
rcu_head);
@@ -733,19 +766,6 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
struct cfg80211_internal_bss *hidden;
struct cfg80211_bss_ies *ies;
- /* First check if the beacon is a probe response from
- * a hidden bss. If so, copy beacon ies (with nullified
- * ssid) into the probe response bss entry (with real ssid).
- * It is required basically for PSM implementation
- * (probe responses do not contain tim ie) */
-
- /* TODO: The code is not trying to update existing probe
- * response bss entries when beacon ies are
- * getting changed. */
- hidden = rb_find_hidden_bss(dev, tmp);
- if (hidden)
- copy_hidden_ies(tmp, hidden);
-
/*
* create a copy -- the "res" variable that is passed in
* is allocated on the stack since it's not needed in the
@@ -760,21 +780,51 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
if (ies)
kfree_rcu(ies, rcu_head);
- spin_unlock_bh(&dev->bss_lock);
- return NULL;
+ goto drop;
}
memcpy(new, tmp, sizeof(*new));
- kref_init(&new->ref);
+ new->refcount = 1;
+ INIT_LIST_HEAD(&new->hidden_list);
+
+ if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
+ hidden = rb_find_bss(dev, tmp, BSS_CMP_HIDE_ZLEN);
+ if (!hidden)
+ hidden = rb_find_bss(dev, 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(dev, new)) {
+ kfree(new);
+ goto drop;
+ }
+ }
+
list_add_tail(&new->list, &dev->bss_list);
rb_insert_bss(dev, new);
found = new;
}
dev->bss_generation++;
+ bss_ref_get(dev, found);
spin_unlock_bh(&dev->bss_lock);
- kref_get(&found->ref);
return found;
+ drop:
+ spin_unlock_bh(&dev->bss_lock);
+ return NULL;
}
static struct ieee80211_channel *
@@ -833,7 +883,6 @@ cfg80211_inform_bss(struct wiphy *wiphy,
memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
tmp.pub.channel = channel;
tmp.pub.signal = signal;
- tmp.pub.tsf = tsf;
tmp.pub.beacon_interval = beacon_interval;
tmp.pub.capability = capability;
/*
@@ -841,16 +890,14 @@ cfg80211_inform_bss(struct wiphy *wiphy,
* 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 iies pointer should we have received an earlier
+ * override the IEs pointer should we have received an earlier
* indication of Probe Response data.
- *
- * The initial buffer for the IEs is allocated with the BSS entry and
- * is located after the private area.
*/
ies = kmalloc(sizeof(*ies) + ielen, gfp);
if (!ies)
return NULL;
ies->len = ielen;
+ ies->tsf = tsf;
memcpy(ies->data, ie, ielen);
rcu_assign_pointer(tmp.pub.beacon_ies, ies);
@@ -907,6 +954,7 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy,
if (!ies)
return NULL;
ies->len = ielen;
+ ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
if (ieee80211_is_probe_resp(mgmt->frame_control))
@@ -918,7 +966,6 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy,
memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
tmp.pub.channel = channel;
tmp.pub.signal = signal;
- tmp.pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
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);
@@ -935,27 +982,35 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy,
}
EXPORT_SYMBOL(cfg80211_inform_bss_frame);
-void cfg80211_ref_bss(struct cfg80211_bss *pub)
+void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
{
+ struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
struct cfg80211_internal_bss *bss;
if (!pub)
return;
bss = container_of(pub, struct cfg80211_internal_bss, pub);
- kref_get(&bss->ref);
+
+ spin_lock_bh(&dev->bss_lock);
+ bss_ref_get(dev, bss);
+ spin_unlock_bh(&dev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_ref_bss);
-void cfg80211_put_bss(struct cfg80211_bss *pub)
+void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
{
+ struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
struct cfg80211_internal_bss *bss;
if (!pub)
return;
bss = container_of(pub, struct cfg80211_internal_bss, pub);
- kref_put(&bss->ref, bss_release);
+
+ spin_lock_bh(&dev->bss_lock);
+ bss_ref_put(dev, bss);
+ spin_unlock_bh(&dev->bss_lock);
}
EXPORT_SYMBOL(cfg80211_put_bss);
@@ -971,8 +1026,8 @@ void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
spin_lock_bh(&dev->bss_lock);
if (!list_empty(&bss->list)) {
- __cfg80211_unlink_bss(dev, bss);
- dev->bss_generation++;
+ if (__cfg80211_unlink_bss(dev, bss))
+ dev->bss_generation++;
}
spin_unlock_bh(&dev->bss_lock);
}
@@ -1155,16 +1210,6 @@ static void ieee80211_scan_add_ies(struct iw_request_info *info,
}
}
-static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
-{
- unsigned long end = jiffies;
-
- if (end >= start)
- return jiffies_to_msecs(end - start);
-
- return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
-}
-
static char *
ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
struct cfg80211_internal_bss *bss, char *current_ev,
@@ -1241,15 +1286,10 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
rcu_read_lock();
ies = rcu_dereference(bss->pub.ies);
- if (ies) {
- rem = ies->len;
- ie = ies->data;
- } else {
- rem = 0;
- ie = NULL;
- }
+ rem = ies->len;
+ ie = ies->data;
- while (ies && rem >= 2) {
+ while (rem >= 2) {
/* invalid data */
if (ie[1] > rem - 2)
break;
@@ -1362,7 +1402,7 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
if (buf) {
memset(&iwe, 0, sizeof(iwe));
iwe.cmd = IWEVCUSTOM;
- sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
+ sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
iwe.u.data.length = strlen(buf);
current_ev = iwe_stream_add_point(info, current_ev, end_buf,
&iwe, buf);