diff options
Diffstat (limited to 'net/wireless/scan.c')
| -rw-r--r-- | net/wireless/scan.c | 1877 |
1 files changed, 1877 insertions, 0 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c new file mode 100644 index 000000000..d87134903 --- /dev/null +++ b/net/wireless/scan.c @@ -0,0 +1,1877 @@ +// 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 + */ +#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++; + } +} + +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); + } + 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); + 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; +} + +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; + + WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); + + list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list) { + 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); +} + +const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len, + const u8 *match, int match_len, + int match_offset) +{ + const struct element *elem; + + /* match_offset can't be smaller than 2, unless match_len is + * zero, in which case match_offset must be zero as well. + */ + if (WARN_ON((match_len && match_offset < 2) || + (!match_len && match_offset))) + return NULL; + + for_each_element_id(elem, eid, ies, len) { + if (elem->datalen >= match_offset - 2 + match_len && + !memcmp(elem->data + match_offset - 2, match, match_len)) + return (void *)elem; + } + + return NULL; +} +EXPORT_SYMBOL(cfg80211_find_ie_match); + +const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type, + const u8 *ies, int len) +{ + const u8 *ie; + 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; + + ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len, + match, match_len, 2); + + if (ie && (ie[1] < 4)) + return NULL; + + return ie; +} +EXPORT_SYMBOL(cfg80211_find_vendor_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; +} + +/** + * 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; +} + +/* Returned bss is reference counted and must be cleaned up appropriately. */ +static struct cfg80211_internal_bss * +cfg80211_bss_update(struct cfg80211_registered_device *rdev, + struct cfg80211_internal_bss *tmp, + bool signal_valid) +{ + struct cfg80211_internal_bss *found = NULL; + + if (WARN_ON(!tmp->pub.channel)) + return NULL; + + tmp->ts = jiffies; + + 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) { + /* Update IEs */ + if (rcu_access_pointer(tmp->pub.proberesp_ies)) { + const struct cfg80211_bss_ies *old; + + old = rcu_access_pointer(found->pub.proberesp_ies); + + rcu_assign_pointer(found->pub.proberesp_ies, + tmp->pub.proberesp_ies); + /* Override possible earlier Beacon frame IEs */ + rcu_assign_pointer(found->pub.ies, + tmp->pub.proberesp_ies); + if (old) + kfree_rcu((struct cfg80211_bss_ies *)old, + rcu_head); + } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { + const struct cfg80211_bss_ies *old; + struct cfg80211_internal_bss *bss; + + if (found->pub.hidden_beacon_bss && + !list_empty(&found->hidden_list)) { + const struct cfg80211_bss_ies *f; + + /* + * 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. + */ + + f = rcu_access_pointer(tmp->pub.beacon_ies); + kfree_rcu((struct cfg80211_bss_ies *)f, + rcu_head); + goto drop; + } + + old = rcu_access_pointer(found->pub.beacon_ies); + + rcu_assign_pointer(found->pub.beacon_ies, + tmp->pub.beacon_ies); + + /* Override IEs if they were from a beacon before */ + 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); + } + + found->pub.beacon_interval = tmp->pub.beacon_interval; + /* + * don't update the signal if beacon was heard on + * adjacent channel. + */ + if (signal_valid) + found->pub.signal = tmp->pub.signal; + found->pub.capability = tmp->pub.capability; + found->ts = tmp->ts; + found->ts_boottime = tmp->ts_boottime; + found->parent_tsf = tmp->parent_tsf; + found->pub.chains = tmp->pub.chains; + memcpy(found->pub.chain_signal, tmp->pub.chain_signal, + IEEE80211_MAX_CHAINS); + ether_addr_copy(found->parent_bssid, tmp->parent_bssid); + } 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); + + 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)) { + bss_ref_put(rdev, new); + goto drop; + } + } + + if (rdev->bss_entries >= bss_entries_limit && + !cfg80211_bss_expire_oldest(rdev)) { + bss_ref_put(rdev, new); + goto drop; + } + + 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_frequency(channel_number, channel->band); + alt_channel = ieee80211_get_channel(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. */ +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_ies *ies; + struct ieee80211_channel *channel; + struct cfg80211_internal_bss tmp = {}, *res; + int bss_type; + bool signal_valid; + + 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 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 to assign */ + 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 = abs(data->chan->center_freq - channel->center_freq) <= + wiphy->max_adj_channel_rssi_comp; + res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); + 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; +} +EXPORT_SYMBOL(cfg80211_inform_bss_data); + +/* cfg80211_inform_bss_width_frame helper */ +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_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 = abs(data->chan->center_freq - channel->center_freq) <= + wiphy->max_adj_channel_rssi_comp; + res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); + 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; +} +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; + + 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)) { + if (__cfg80211_unlink_bss(rdev, bss)) + rdev->bss_generation++; + } + spin_unlock_bh(&rdev->bss_lock); +} +EXPORT_SYMBOL(cfg80211_unlink_bss); + +#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 |