X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=net%2Fmac80211%2Fscan.c;h=e1b0be7a57b9772ddb1c006793ca6a5929580aba;hp=0989b1c062e3faaf560c1d03aa4c79d0f2f3b113;hb=f8965467f366fd18f01feafb5db10512d7b4422c;hpb=d73782fdde76554016abf73b46f843b29f520848 diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index 0989b1c..e1b0be7 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -12,210 +12,66 @@ * published by the Free Software Foundation. */ -/* TODO: - * order BSS list by RSSI(?) ("quality of AP") - * scan result table filtering (by capability (privacy, IBSS/BSS, WPA/RSN IE, - * SSID) - */ - -#include #include +#include +#include +#include +#include #include -#include #include "ieee80211_i.h" +#include "driver-ops.h" #include "mesh.h" #define IEEE80211_PROBE_DELAY (HZ / 33) #define IEEE80211_CHANNEL_TIME (HZ / 33) -#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5) - -void ieee80211_rx_bss_list_init(struct ieee80211_local *local) -{ - spin_lock_init(&local->bss_lock); - INIT_LIST_HEAD(&local->bss_list); -} - -void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local) -{ - struct ieee80211_bss *bss, *tmp; - - list_for_each_entry_safe(bss, tmp, &local->bss_list, list) - ieee80211_rx_bss_put(local, bss); -} +#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) struct ieee80211_bss * ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, u8 *ssid, u8 ssid_len) { - struct ieee80211_bss *bss; - - spin_lock_bh(&local->bss_lock); - bss = local->bss_hash[STA_HASH(bssid)]; - while (bss) { - if (!bss_mesh_cfg(bss) && - !memcmp(bss->bssid, bssid, ETH_ALEN) && - bss->freq == freq && - bss->ssid_len == ssid_len && - (ssid_len == 0 || !memcmp(bss->ssid, ssid, ssid_len))) { - atomic_inc(&bss->users); - break; - } - bss = bss->hnext; - } - spin_unlock_bh(&local->bss_lock); - return bss; -} - -/* Caller must hold local->bss_lock */ -static void __ieee80211_rx_bss_hash_add(struct ieee80211_local *local, - struct ieee80211_bss *bss) -{ - u8 hash_idx; - - if (bss_mesh_cfg(bss)) - hash_idx = mesh_id_hash(bss_mesh_id(bss), - bss_mesh_id_len(bss)); - else - hash_idx = STA_HASH(bss->bssid); - - bss->hnext = local->bss_hash[hash_idx]; - local->bss_hash[hash_idx] = bss; -} - -/* Caller must hold local->bss_lock */ -static void __ieee80211_rx_bss_hash_del(struct ieee80211_local *local, - struct ieee80211_bss *bss) -{ - struct ieee80211_bss *b, *prev = NULL; - b = local->bss_hash[STA_HASH(bss->bssid)]; - while (b) { - if (b == bss) { - if (!prev) - local->bss_hash[STA_HASH(bss->bssid)] = - bss->hnext; - else - prev->hnext = bss->hnext; - break; - } - prev = b; - b = b->hnext; - } -} - -struct ieee80211_bss * -ieee80211_rx_bss_add(struct ieee80211_local *local, u8 *bssid, int freq, - u8 *ssid, u8 ssid_len) -{ - struct ieee80211_bss *bss; + struct cfg80211_bss *cbss; - bss = kzalloc(sizeof(*bss), GFP_ATOMIC); - if (!bss) + cbss = cfg80211_get_bss(local->hw.wiphy, + ieee80211_get_channel(local->hw.wiphy, freq), + bssid, ssid, ssid_len, 0, 0); + if (!cbss) return NULL; - atomic_set(&bss->users, 2); - memcpy(bss->bssid, bssid, ETH_ALEN); - bss->freq = freq; - if (ssid && ssid_len <= IEEE80211_MAX_SSID_LEN) { - memcpy(bss->ssid, ssid, ssid_len); - bss->ssid_len = ssid_len; - } - - spin_lock_bh(&local->bss_lock); - /* TODO: order by RSSI? */ - list_add_tail(&bss->list, &local->bss_list); - __ieee80211_rx_bss_hash_add(local, bss); - spin_unlock_bh(&local->bss_lock); - return bss; + return (void *)cbss->priv; } -#ifdef CONFIG_MAC80211_MESH -static struct ieee80211_bss * -ieee80211_rx_mesh_bss_get(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len, - u8 *mesh_cfg, int freq) +static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) { - struct ieee80211_bss *bss; + struct ieee80211_bss *bss = (void *)cbss->priv; - spin_lock_bh(&local->bss_lock); - bss = local->bss_hash[mesh_id_hash(mesh_id, mesh_id_len)]; - while (bss) { - if (bss_mesh_cfg(bss) && - !memcmp(bss_mesh_cfg(bss), mesh_cfg, MESH_CFG_CMP_LEN) && - bss->freq == freq && - mesh_id_len == bss->mesh_id_len && - (mesh_id_len == 0 || !memcmp(bss->mesh_id, mesh_id, - mesh_id_len))) { - atomic_inc(&bss->users); - break; - } - bss = bss->hnext; - } - spin_unlock_bh(&local->bss_lock); - return bss; -} - -static struct ieee80211_bss * -ieee80211_rx_mesh_bss_add(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len, - u8 *mesh_cfg, int mesh_config_len, int freq) -{ - struct ieee80211_bss *bss; - - if (mesh_config_len != MESH_CFG_LEN) - return NULL; - - bss = kzalloc(sizeof(*bss), GFP_ATOMIC); - if (!bss) - return NULL; - - bss->mesh_cfg = kmalloc(MESH_CFG_CMP_LEN, GFP_ATOMIC); - if (!bss->mesh_cfg) { - kfree(bss); - return NULL; - } - - if (mesh_id_len && mesh_id_len <= IEEE80211_MAX_MESH_ID_LEN) { - bss->mesh_id = kmalloc(mesh_id_len, GFP_ATOMIC); - if (!bss->mesh_id) { - kfree(bss->mesh_cfg); - kfree(bss); - return NULL; - } - memcpy(bss->mesh_id, mesh_id, mesh_id_len); - } - - atomic_set(&bss->users, 2); - memcpy(bss->mesh_cfg, mesh_cfg, MESH_CFG_CMP_LEN); - bss->mesh_id_len = mesh_id_len; - bss->freq = freq; - spin_lock_bh(&local->bss_lock); - /* TODO: order by RSSI? */ - list_add_tail(&bss->list, &local->bss_list); - __ieee80211_rx_bss_hash_add(local, bss); - spin_unlock_bh(&local->bss_lock); - return bss; -} -#endif - -static void ieee80211_rx_bss_free(struct ieee80211_bss *bss) -{ - kfree(bss->ies); kfree(bss_mesh_id(bss)); kfree(bss_mesh_cfg(bss)); - kfree(bss); } void ieee80211_rx_bss_put(struct ieee80211_local *local, struct ieee80211_bss *bss) { - local_bh_disable(); - if (!atomic_dec_and_lock(&bss->users, &local->bss_lock)) { - local_bh_enable(); + if (!bss) return; - } + cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); +} - __ieee80211_rx_bss_hash_del(local, bss); - list_del(&bss->list); - spin_unlock_bh(&local->bss_lock); - ieee80211_rx_bss_free(bss); +static bool is_uapsd_supported(struct ieee802_11_elems *elems) +{ + u8 qos_info; + + if (elems->wmm_info && elems->wmm_info_len == 7 + && elems->wmm_info[5] == 1) + qos_info = elems->wmm_info[6]; + else if (elems->wmm_param && elems->wmm_param_len == 24 + && elems->wmm_param[5] == 1) + qos_info = elems->wmm_param[6]; + else + /* no valid wmm information or parameter element found */ + return false; + + return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; } struct ieee80211_bss * @@ -224,39 +80,27 @@ ieee80211_bss_info_update(struct ieee80211_local *local, struct ieee80211_mgmt *mgmt, size_t len, struct ieee802_11_elems *elems, - int freq, bool beacon) + struct ieee80211_channel *channel, + bool beacon) { + struct cfg80211_bss *cbss; struct ieee80211_bss *bss; - int clen; + int clen, srlen; + s32 signal = 0; -#ifdef CONFIG_MAC80211_MESH - if (elems->mesh_config) - bss = ieee80211_rx_mesh_bss_get(local, elems->mesh_id, - elems->mesh_id_len, elems->mesh_config, freq); - else -#endif - bss = ieee80211_rx_bss_get(local, mgmt->bssid, freq, - elems->ssid, elems->ssid_len); - if (!bss) { -#ifdef CONFIG_MAC80211_MESH - if (elems->mesh_config) - bss = ieee80211_rx_mesh_bss_add(local, elems->mesh_id, - elems->mesh_id_len, elems->mesh_config, - elems->mesh_config_len, freq); - else -#endif - bss = ieee80211_rx_bss_add(local, mgmt->bssid, freq, - elems->ssid, elems->ssid_len); - if (!bss) - return NULL; - } else { -#if 0 - /* TODO: order by RSSI? */ - spin_lock_bh(&local->bss_lock); - list_move_tail(&bss->list, &local->bss_list); - spin_unlock_bh(&local->bss_lock); -#endif - } + if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) + signal = rx_status->signal * 100; + else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) + signal = (rx_status->signal * 100) / local->hw.max_signal; + + cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, + mgmt, len, signal, GFP_ATOMIC); + + if (!cbss) + return NULL; + + cbss->free_priv = ieee80211_rx_bss_free; + bss = (void *)cbss->priv; /* save the ERP value so that it is available at association time */ if (elems->erp_info && elems->erp_info_len >= 1) { @@ -264,72 +108,44 @@ ieee80211_bss_info_update(struct ieee80211_local *local, bss->has_erp_value = 1; } - bss->beacon_int = le16_to_cpu(mgmt->u.beacon.beacon_int); - bss->capability = le16_to_cpu(mgmt->u.beacon.capab_info); - if (elems->tim) { struct ieee80211_tim_ie *tim_ie = (struct ieee80211_tim_ie *)elems->tim; bss->dtim_period = tim_ie->dtim_period; } - /* set default value for buggy APs */ - if (!elems->tim || bss->dtim_period == 0) - bss->dtim_period = 1; - - bss->supp_rates_len = 0; + /* replace old supported rates if we get new values */ + srlen = 0; if (elems->supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; + clen = IEEE80211_MAX_SUPP_RATES; if (clen > elems->supp_rates_len) clen = elems->supp_rates_len; - memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, - clen); - bss->supp_rates_len += clen; + memcpy(bss->supp_rates, elems->supp_rates, clen); + srlen += clen; } if (elems->ext_supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; + clen = IEEE80211_MAX_SUPP_RATES - srlen; if (clen > elems->ext_supp_rates_len) clen = elems->ext_supp_rates_len; - memcpy(&bss->supp_rates[bss->supp_rates_len], - elems->ext_supp_rates, clen); - bss->supp_rates_len += clen; + memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen); + srlen += clen; } + if (srlen) + bss->supp_rates_len = srlen; - bss->band = rx_status->band; - - bss->timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); - bss->last_update = jiffies; - bss->signal = rx_status->signal; - bss->noise = rx_status->noise; - bss->qual = rx_status->qual; bss->wmm_used = elems->wmm_param || elems->wmm_info; + bss->uapsd_supported = is_uapsd_supported(elems); if (!beacon) bss->last_probe_resp = jiffies; - /* - * For probe responses, or if we don't have any information yet, - * use the IEs from the beacon. - */ - if (!bss->ies || !beacon) { - if (bss->ies == NULL || bss->ies_len < elems->total_len) { - kfree(bss->ies); - bss->ies = kmalloc(elems->total_len, GFP_ATOMIC); - } - if (bss->ies) { - memcpy(bss->ies, elems->ie_start, elems->total_len); - bss->ies_len = elems->total_len; - } else - bss->ies_len = 0; - } - return bss; } ieee80211_rx_result -ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, - struct ieee80211_rx_status *rx_status) +ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) { + struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); struct ieee80211_mgmt *mgmt; struct ieee80211_bss *bss; u8 *elements; @@ -355,7 +171,7 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, presp = ieee80211_is_probe_resp(fc); if (presp) { /* ignore ProbeResp to foreign address */ - if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) + if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) return RX_DROP_MONITOR; presp = true; @@ -387,7 +203,7 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, bss = ieee80211_bss_info_update(sdata->local, rx_status, mgmt, skb->len, &elems, - freq, beacon); + channel, beacon); if (bss) ieee80211_rx_bss_put(sdata->local, bss); @@ -395,534 +211,585 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, return RX_QUEUED; } -static void ieee80211_send_nullfunc(struct ieee80211_local *local, - struct ieee80211_sub_if_data *sdata, - int powersave) +/* return false if no more work */ +static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) { - struct sk_buff *skb; - struct ieee80211_hdr *nullfunc; - __le16 fc; + struct cfg80211_scan_request *req = local->scan_req; + enum ieee80211_band band; + int i, ielen, n_chans; + + do { + if (local->hw_scan_band == IEEE80211_NUM_BANDS) + return false; + + band = local->hw_scan_band; + n_chans = 0; + for (i = 0; i < req->n_channels; i++) { + if (req->channels[i]->band == band) { + local->hw_scan_req->channels[n_chans] = + req->channels[i]; + n_chans++; + } + } - skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24); - if (!skb) { - printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc " - "frame\n", sdata->dev->name); - return; - } - skb_reserve(skb, local->hw.extra_tx_headroom); - - nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24); - memset(nullfunc, 0, 24); - fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC | - IEEE80211_FCTL_TODS); - if (powersave) - fc |= cpu_to_le16(IEEE80211_FCTL_PM); - nullfunc->frame_control = fc; - memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN); - memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN); - memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN); - - ieee80211_tx_skb(sdata, skb, 0); + local->hw_scan_band++; + } while (!n_chans); + + local->hw_scan_req->n_channels = n_chans; + + ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, + req->ie, req->ie_len, band); + local->hw_scan_req->ie_len = ielen; + + return true; } -void ieee80211_scan_completed(struct ieee80211_hw *hw) +void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) { struct ieee80211_local *local = hw_to_local(hw); - struct ieee80211_sub_if_data *sdata; - union iwreq_data wrqu; + bool was_hw_scan; - if (WARN_ON(!local->hw_scanning && !local->sw_scanning)) - return; + trace_api_scan_completed(local, aborted); - local->last_scan_completed = jiffies; - memset(&wrqu, 0, sizeof(wrqu)); + mutex_lock(&local->scan_mtx); /* - * local->scan_sdata could have been NULLed by the interface - * down code in case we were scanning on an interface that is - * being taken down. + * It's ok to abort a not-yet-running scan (that + * we have one at all will be verified by checking + * local->scan_req next), but not to complete it + * successfully. */ - sdata = local->scan_sdata; - if (sdata) - wireless_send_event(sdata->dev, SIOCGIWSCAN, &wrqu, NULL); + if (WARN_ON(!local->scanning && !aborted)) + aborted = true; - if (local->hw_scanning) { - local->hw_scanning = false; - ieee80211_hw_config(local); - goto done; + if (WARN_ON(!local->scan_req)) { + mutex_unlock(&local->scan_mtx); + return; } - local->sw_scanning = false; - ieee80211_hw_config(local); + was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); + if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { + ieee80211_queue_delayed_work(&local->hw, + &local->scan_work, 0); + mutex_unlock(&local->scan_mtx); + return; + } - netif_tx_lock_bh(local->mdev); - netif_addr_lock(local->mdev); - local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC; - local->ops->configure_filter(local_to_hw(local), - FIF_BCN_PRBRESP_PROMISC, - &local->filter_flags, - local->mdev->mc_count, - local->mdev->mc_list); + kfree(local->hw_scan_req); + local->hw_scan_req = NULL; - netif_addr_unlock(local->mdev); - netif_tx_unlock_bh(local->mdev); + if (local->scan_req != local->int_scan_req) + cfg80211_scan_done(local->scan_req, aborted); + local->scan_req = NULL; + local->scan_sdata = NULL; - rcu_read_lock(); - list_for_each_entry_rcu(sdata, &local->interfaces, list) { - /* Tell AP we're back */ - if (sdata->vif.type == NL80211_IFTYPE_STATION) { - if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) { - ieee80211_send_nullfunc(local, sdata, 0); - netif_tx_wake_all_queues(sdata->dev); - } - } else - netif_tx_wake_all_queues(sdata->dev); - } - rcu_read_unlock(); + local->scanning = 0; + local->scan_channel = NULL; + + /* we only have to protect scan_req and hw/sw scan */ + mutex_unlock(&local->scan_mtx); + + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if (was_hw_scan) + goto done; + + ieee80211_configure_filter(local); + + drv_sw_scan_complete(local); + + ieee80211_offchannel_return(local, true); done: + ieee80211_recalc_idle(local); ieee80211_mlme_notify_scan_completed(local); + ieee80211_ibss_notify_scan_completed(local); ieee80211_mesh_notify_scan_completed(local); + ieee80211_queue_work(&local->hw, &local->work_work); } EXPORT_SYMBOL(ieee80211_scan_completed); - -void ieee80211_scan_work(struct work_struct *work) +static int ieee80211_start_sw_scan(struct ieee80211_local *local) { - struct ieee80211_local *local = - container_of(work, struct ieee80211_local, scan_work.work); - struct ieee80211_sub_if_data *sdata = local->scan_sdata; - struct ieee80211_supported_band *sband; - struct ieee80211_channel *chan; - int skip; - unsigned long next_delay = 0; - /* - * Avoid re-scheduling when the sdata is going away. + * Hardware/driver doesn't support hw_scan, so use software + * scanning instead. First send a nullfunc frame with power save + * bit on so that AP will buffer the frames for us while we are not + * listening, then send probe requests to each channel and wait for + * the responses. After all channels are scanned, tune back to the + * original channel and send a nullfunc frame with power save bit + * off to trigger the AP to send us all the buffered frames. + * + * Note that while local->sw_scanning is true everything else but + * nullfunc frames and probe requests will be dropped in + * ieee80211_tx_h_check_assoc(). */ - if (!netif_running(sdata->dev)) - return; + drv_sw_scan_start(local); - switch (local->scan_state) { - case SCAN_SET_CHANNEL: - /* - * Get current scan band. scan_band may be IEEE80211_NUM_BANDS - * after we successfully scanned the last channel of the last - * band (and the last band is supported by the hw) - */ - if (local->scan_band < IEEE80211_NUM_BANDS) - sband = local->hw.wiphy->bands[local->scan_band]; - else - sband = NULL; + ieee80211_offchannel_stop_beaconing(local); - /* - * If we are at an unsupported band and have more bands - * left to scan, advance to the next supported one. - */ - while (!sband && local->scan_band < IEEE80211_NUM_BANDS - 1) { - local->scan_band++; - sband = local->hw.wiphy->bands[local->scan_band]; - local->scan_channel_idx = 0; - } + local->leave_oper_channel_time = 0; + local->next_scan_state = SCAN_DECISION; + local->scan_channel_idx = 0; - /* if no more bands/channels left, complete scan */ - if (!sband || local->scan_channel_idx >= sband->n_channels) { - ieee80211_scan_completed(local_to_hw(local)); - return; - } - skip = 0; - chan = &sband->channels[local->scan_channel_idx]; - - if (chan->flags & IEEE80211_CHAN_DISABLED || - (sdata->vif.type == NL80211_IFTYPE_ADHOC && - chan->flags & IEEE80211_CHAN_NO_IBSS)) - skip = 1; - - if (!skip) { - local->scan_channel = chan; - if (ieee80211_hw_config(local)) - skip = 1; - } + drv_flush(local, false); - /* advance state machine to next channel/band */ - local->scan_channel_idx++; - if (local->scan_channel_idx >= sband->n_channels) { - /* - * scan_band may end up == IEEE80211_NUM_BANDS, but - * we'll catch that case above and complete the scan - * if that is the case. - */ - local->scan_band++; - local->scan_channel_idx = 0; - } + ieee80211_configure_filter(local); - if (skip) - break; + ieee80211_queue_delayed_work(&local->hw, + &local->scan_work, + IEEE80211_CHANNEL_TIME); - next_delay = IEEE80211_PROBE_DELAY + - usecs_to_jiffies(local->hw.channel_change_time); - local->scan_state = SCAN_SEND_PROBE; - break; - case SCAN_SEND_PROBE: - next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; - local->scan_state = SCAN_SET_CHANNEL; + return 0; +} - if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN) - break; - ieee80211_send_probe_req(sdata, NULL, local->scan_ssid, - local->scan_ssid_len); - next_delay = IEEE80211_CHANNEL_TIME; - break; + +static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, + struct cfg80211_scan_request *req) +{ + struct ieee80211_local *local = sdata->local; + int rc; + + if (local->scan_req) + return -EBUSY; + + if (!list_empty(&local->work_list)) { + /* wait for the work to finish/time out */ + local->scan_req = req; + local->scan_sdata = sdata; + return 0; } - queue_delayed_work(local->hw.workqueue, &local->scan_work, - next_delay); -} + if (local->ops->hw_scan) { + u8 *ies; + local->hw_scan_req = kmalloc( + sizeof(*local->hw_scan_req) + + req->n_channels * sizeof(req->channels[0]) + + 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + + req->ie_len, GFP_KERNEL); + if (!local->hw_scan_req) + return -ENOMEM; -int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata, - u8 *ssid, size_t ssid_len) -{ - struct ieee80211_local *local = scan_sdata->local; - struct ieee80211_sub_if_data *sdata; + local->hw_scan_req->ssids = req->ssids; + local->hw_scan_req->n_ssids = req->n_ssids; + ies = (u8 *)local->hw_scan_req + + sizeof(*local->hw_scan_req) + + req->n_channels * sizeof(req->channels[0]); + local->hw_scan_req->ie = ies; - if (ssid_len > IEEE80211_MAX_SSID_LEN) - return -EINVAL; - - /* MLME-SCAN.request (page 118) page 144 (11.1.3.1) - * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS - * BSSID: MACAddress - * SSID - * ScanType: ACTIVE, PASSIVE - * ProbeDelay: delay (in microseconds) to be used prior to transmitting - * a Probe frame during active scanning - * ChannelList - * MinChannelTime (>= ProbeDelay), in TU - * MaxChannelTime: (>= MinChannelTime), in TU - */ + local->hw_scan_band = 0; + + /* + * After allocating local->hw_scan_req, we must + * go through until ieee80211_prep_hw_scan(), so + * anything that might be changed here and leave + * this function early must not go after this + * allocation. + */ + } + + local->scan_req = req; + local->scan_sdata = sdata; + + if (local->ops->hw_scan) + __set_bit(SCAN_HW_SCANNING, &local->scanning); + else + __set_bit(SCAN_SW_SCANNING, &local->scanning); - /* MLME-SCAN.confirm - * BSSDescriptionSet - * ResultCode: SUCCESS, INVALID_PARAMETERS + /* + * Kicking off the scan need not be protected, + * only the scan variable stuff, since now + * local->scan_req is assigned and other callers + * will abort their scan attempts. + * + * This avoids too many locking dependencies + * so that the scan completed calls have more + * locking freedom. */ - if (local->sw_scanning || local->hw_scanning) { - if (local->scan_sdata == scan_sdata) - return 0; - return -EBUSY; - } + ieee80211_recalc_idle(local); + mutex_unlock(&local->scan_mtx); if (local->ops->hw_scan) { - int rc; + WARN_ON(!ieee80211_prep_hw_scan(local)); + rc = drv_hw_scan(local, sdata, local->hw_scan_req); + } else + rc = ieee80211_start_sw_scan(local); - local->hw_scanning = true; - rc = local->ops->hw_scan(local_to_hw(local), ssid, ssid_len); - if (rc) { - local->hw_scanning = false; - return rc; - } - local->scan_sdata = scan_sdata; - return 0; + mutex_lock(&local->scan_mtx); + + if (rc) { + kfree(local->hw_scan_req); + local->hw_scan_req = NULL; + local->scanning = 0; + + ieee80211_recalc_idle(local); + + local->scan_req = NULL; + local->scan_sdata = NULL; } - local->sw_scanning = true; + return rc; +} + +static unsigned long +ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) +{ + /* + * TODO: channel switching also consumes quite some time, + * add that delay as well to get a better estimation + */ + if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) + return IEEE80211_PASSIVE_CHANNEL_TIME; + return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; +} + +static int ieee80211_scan_state_decision(struct ieee80211_local *local, + unsigned long *next_delay) +{ + bool associated = false; + bool tx_empty = true; + bool bad_latency; + bool listen_int_exceeded; + unsigned long min_beacon_int = 0; + struct ieee80211_sub_if_data *sdata; + struct ieee80211_channel *next_chan; + + /* if no more bands/channels left, complete scan and advance to the idle state */ + if (local->scan_channel_idx >= local->scan_req->n_channels) { + ieee80211_scan_completed(&local->hw, false); + return 1; + } + + /* + * check if at least one STA interface is associated, + * check if at least one STA interface has pending tx frames + * and grab the lowest used beacon interval + */ + mutex_lock(&local->iflist_mtx); + list_for_each_entry(sdata, &local->interfaces, list) { + if (!ieee80211_sdata_running(sdata)) + continue; - rcu_read_lock(); - list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (sdata->vif.type == NL80211_IFTYPE_STATION) { - if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) { - netif_tx_stop_all_queues(sdata->dev); - ieee80211_send_nullfunc(local, sdata, 1); + if (sdata->u.mgd.associated) { + associated = true; + + if (sdata->vif.bss_conf.beacon_int < + min_beacon_int || min_beacon_int == 0) + min_beacon_int = + sdata->vif.bss_conf.beacon_int; + + if (!qdisc_all_tx_empty(sdata->dev)) { + tx_empty = false; + break; + } } - } else - netif_tx_stop_all_queues(sdata->dev); + } } - rcu_read_unlock(); + mutex_unlock(&local->iflist_mtx); - if (ssid) { - local->scan_ssid_len = ssid_len; - memcpy(local->scan_ssid, ssid, ssid_len); - } else - local->scan_ssid_len = 0; - local->scan_state = SCAN_SET_CHANNEL; - local->scan_channel_idx = 0; - local->scan_band = IEEE80211_BAND_2GHZ; - local->scan_sdata = scan_sdata; - - netif_addr_lock_bh(local->mdev); - local->filter_flags |= FIF_BCN_PRBRESP_PROMISC; - local->ops->configure_filter(local_to_hw(local), - FIF_BCN_PRBRESP_PROMISC, - &local->filter_flags, - local->mdev->mc_count, - local->mdev->mc_list); - netif_addr_unlock_bh(local->mdev); - - /* TODO: start scan as soon as all nullfunc frames are ACKed */ - queue_delayed_work(local->hw.workqueue, &local->scan_work, - IEEE80211_CHANNEL_TIME); + if (local->scan_channel) { + /* + * we're currently scanning a different channel, let's + * see if we can scan another channel without interfering + * with the current traffic situation. + * + * Since we don't know if the AP has pending frames for us + * we can only check for our tx queues and use the current + * pm_qos requirements for rx. Hence, if no tx traffic occurs + * at all we will scan as many channels in a row as the pm_qos + * latency allows us to. Additionally we also check for the + * currently negotiated listen interval to prevent losing + * frames unnecessarily. + * + * Otherwise switch back to the operating channel. + */ + next_chan = local->scan_req->channels[local->scan_channel_idx]; + + bad_latency = time_after(jiffies + + ieee80211_scan_get_channel_time(next_chan), + local->leave_oper_channel_time + + usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY))); + + listen_int_exceeded = time_after(jiffies + + ieee80211_scan_get_channel_time(next_chan), + local->leave_oper_channel_time + + usecs_to_jiffies(min_beacon_int * 1024) * + local->hw.conf.listen_interval); + + if (associated && ( !tx_empty || bad_latency || + listen_int_exceeded)) + local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; + else + local->next_scan_state = SCAN_SET_CHANNEL; + } else { + /* + * we're on the operating channel currently, let's + * leave that channel now to scan another one + */ + local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; + } + *next_delay = 0; return 0; } - -int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, - u8 *ssid, size_t ssid_len) +static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, + unsigned long *next_delay) { - struct ieee80211_local *local = sdata->local; - struct ieee80211_if_sta *ifsta; + ieee80211_offchannel_stop_station(local); - if (sdata->vif.type != NL80211_IFTYPE_STATION) - return ieee80211_start_scan(sdata, ssid, ssid_len); + __set_bit(SCAN_OFF_CHANNEL, &local->scanning); /* - * STA has a state machine that might need to defer scanning - * while it's trying to associate/authenticate, therefore we - * queue it up to the state machine in that case. + * What if the nullfunc frames didn't arrive? */ + drv_flush(local, false); + if (local->ops->flush) + *next_delay = 0; + else + *next_delay = HZ / 10; - if (local->sw_scanning || local->hw_scanning) { - if (local->scan_sdata == sdata) - return 0; - return -EBUSY; - } + /* remember when we left the operating channel */ + local->leave_oper_channel_time = jiffies; + + /* advance to the next channel to be scanned */ + local->next_scan_state = SCAN_SET_CHANNEL; +} + +static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, + unsigned long *next_delay) +{ + /* switch back to the operating channel */ + local->scan_channel = NULL; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); - ifsta = &sdata->u.sta; + /* + * Only re-enable station mode interface now; beaconing will be + * re-enabled once the full scan has been completed. + */ + ieee80211_offchannel_return(local, false); - ifsta->scan_ssid_len = ssid_len; - if (ssid_len) - memcpy(ifsta->scan_ssid, ssid, ssid_len); - set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request); - queue_work(local->hw.workqueue, &ifsta->work); + __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); - return 0; + *next_delay = HZ / 5; + local->next_scan_state = SCAN_DECISION; } - -static void ieee80211_scan_add_ies(struct iw_request_info *info, - struct ieee80211_bss *bss, - char **current_ev, char *end_buf) +static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, + unsigned long *next_delay) { - u8 *pos, *end, *next; - struct iw_event iwe; + int skip; + struct ieee80211_channel *chan; + + skip = 0; + chan = local->scan_req->channels[local->scan_channel_idx]; + + local->scan_channel = chan; + if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) + skip = 1; - if (bss == NULL || bss->ies == NULL) + /* advance state machine to next channel/band */ + local->scan_channel_idx++; + + if (skip) { + /* if we skip this channel return to the decision state */ + local->next_scan_state = SCAN_DECISION; return; + } /* - * If needed, fragment the IEs buffer (at IE boundaries) into short - * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. + * Probe delay is used to update the NAV, cf. 11.1.3.2.2 + * (which unfortunately doesn't say _why_ step a) is done, + * but it waits for the probe delay or until a frame is + * received - and the received frame would update the NAV). + * For now, we do not support waiting until a frame is + * received. + * + * In any case, it is not necessary for a passive scan. */ - pos = bss->ies; - end = pos + bss->ies_len; + if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || + !local->scan_req->n_ssids) { + *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; + local->next_scan_state = SCAN_DECISION; + return; + } - 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]; + /* active scan, send probes */ + *next_delay = IEEE80211_PROBE_DELAY; + local->next_scan_state = SCAN_SEND_PROBE; +} - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVGENIE; - iwe.u.data.length = next - pos; - *current_ev = iwe_stream_add_point(info, *current_ev, - end_buf, &iwe, pos); +static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, + unsigned long *next_delay) +{ + int i; + struct ieee80211_sub_if_data *sdata = local->scan_sdata; - pos = next; - } + for (i = 0; i < local->scan_req->n_ssids; i++) + ieee80211_send_probe_req( + sdata, NULL, + local->scan_req->ssids[i].ssid, + local->scan_req->ssids[i].ssid_len, + local->scan_req->ie, local->scan_req->ie_len); - if (end > pos) { - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVGENIE; - iwe.u.data.length = end - pos; - *current_ev = iwe_stream_add_point(info, *current_ev, - end_buf, &iwe, pos); - } + /* + * After sending probe requests, wait for probe responses + * on the channel. + */ + *next_delay = IEEE80211_CHANNEL_TIME; + local->next_scan_state = SCAN_DECISION; } - -static char * -ieee80211_scan_result(struct ieee80211_local *local, - struct iw_request_info *info, - struct ieee80211_bss *bss, - char *current_ev, char *end_buf) +void ieee80211_scan_work(struct work_struct *work) { - struct iw_event iwe; - char *buf; - - if (time_after(jiffies, - bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE)) - return current_ev; - - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWAP; - iwe.u.ap_addr.sa_family = ARPHRD_ETHER; - memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN); - current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe, - IW_EV_ADDR_LEN); - - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWESSID; - if (bss_mesh_cfg(bss)) { - iwe.u.data.length = bss_mesh_id_len(bss); - iwe.u.data.flags = 1; - current_ev = iwe_stream_add_point(info, current_ev, end_buf, - &iwe, bss_mesh_id(bss)); - } else { - iwe.u.data.length = bss->ssid_len; - iwe.u.data.flags = 1; - current_ev = iwe_stream_add_point(info, current_ev, end_buf, - &iwe, bss->ssid); + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, scan_work.work); + struct ieee80211_sub_if_data *sdata = local->scan_sdata; + unsigned long next_delay = 0; + + mutex_lock(&local->scan_mtx); + if (!sdata || !local->scan_req) { + mutex_unlock(&local->scan_mtx); + return; } - if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) - || bss_mesh_cfg(bss)) { - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWMODE; - if (bss_mesh_cfg(bss)) - iwe.u.mode = IW_MODE_MESH; - else if (bss->capability & WLAN_CAPABILITY_ESS) - iwe.u.mode = IW_MODE_MASTER; - else - iwe.u.mode = IW_MODE_ADHOC; - current_ev = iwe_stream_add_event(info, current_ev, end_buf, - &iwe, IW_EV_UINT_LEN); + if (local->hw_scan_req) { + int rc = drv_hw_scan(local, sdata, local->hw_scan_req); + mutex_unlock(&local->scan_mtx); + if (rc) + ieee80211_scan_completed(&local->hw, true); + return; } - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWFREQ; - iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq); - iwe.u.freq.e = 0; - current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe, - IW_EV_FREQ_LEN); - - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWFREQ; - iwe.u.freq.m = bss->freq; - iwe.u.freq.e = 6; - current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe, - IW_EV_FREQ_LEN); - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVQUAL; - iwe.u.qual.qual = bss->qual; - iwe.u.qual.level = bss->signal; - iwe.u.qual.noise = bss->noise; - iwe.u.qual.updated = local->wstats_flags; - current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe, - IW_EV_QUAL_LEN); - - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = SIOCGIWENCODE; - if (bss->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(info, current_ev, end_buf, - &iwe, ""); - - ieee80211_scan_add_ies(info, bss, ¤t_ev, end_buf); - - if (bss->supp_rates_len > 0) { - /* display all supported rates in readable format */ - char *p = current_ev + iwe_stream_lcp_len(info); - int i; - - 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 < bss->supp_rates_len; i++) { - iwe.u.bitrate.value = ((bss->supp_rates[i] & - 0x7f) * 500000); - p = iwe_stream_add_value(info, current_ev, p, - end_buf, &iwe, IW_EV_PARAM_LEN); - } - current_ev = p; + if (local->scan_req && !local->scanning) { + struct cfg80211_scan_request *req = local->scan_req; + int rc; + + local->scan_req = NULL; + local->scan_sdata = NULL; + + rc = __ieee80211_start_scan(sdata, req); + mutex_unlock(&local->scan_mtx); + + if (rc) + ieee80211_scan_completed(&local->hw, true); + return; } - buf = kmalloc(30, GFP_ATOMIC); - if (buf) { - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVCUSTOM; - sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp)); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, end_buf, - &iwe, buf); - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVCUSTOM; - sprintf(buf, " Last beacon: %dms ago", - jiffies_to_msecs(jiffies - bss->last_update)); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, &iwe, buf); - kfree(buf); + mutex_unlock(&local->scan_mtx); + + /* + * Avoid re-scheduling when the sdata is going away. + */ + if (!ieee80211_sdata_running(sdata)) { + ieee80211_scan_completed(&local->hw, true); + return; } - if (bss_mesh_cfg(bss)) { - u8 *cfg = bss_mesh_cfg(bss); - buf = kmalloc(50, GFP_ATOMIC); - if (buf) { - memset(&iwe, 0, sizeof(iwe)); - iwe.cmd = IWEVCUSTOM; - sprintf(buf, "Mesh network (version %d)", cfg[0]); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, - &iwe, buf); - sprintf(buf, "Path Selection Protocol ID: " - "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3], - cfg[4]); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, - &iwe, buf); - sprintf(buf, "Path Selection Metric ID: " - "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7], - cfg[8]); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, - &iwe, buf); - sprintf(buf, "Congestion Control Mode ID: " - "0x%02X%02X%02X%02X", cfg[9], cfg[10], - cfg[11], cfg[12]); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, - &iwe, buf); - sprintf(buf, "Channel Precedence: " - "0x%02X%02X%02X%02X", cfg[13], cfg[14], - cfg[15], cfg[16]); - iwe.u.data.length = strlen(buf); - current_ev = iwe_stream_add_point(info, current_ev, - end_buf, - &iwe, buf); - kfree(buf); + /* + * as long as no delay is required advance immediately + * without scheduling a new work + */ + do { + switch (local->next_scan_state) { + case SCAN_DECISION: + if (ieee80211_scan_state_decision(local, &next_delay)) + return; + break; + case SCAN_SET_CHANNEL: + ieee80211_scan_state_set_channel(local, &next_delay); + break; + case SCAN_SEND_PROBE: + ieee80211_scan_state_send_probe(local, &next_delay); + break; + case SCAN_LEAVE_OPER_CHANNEL: + ieee80211_scan_state_leave_oper_channel(local, &next_delay); + break; + case SCAN_ENTER_OPER_CHANNEL: + ieee80211_scan_state_enter_oper_channel(local, &next_delay); + break; } - } + } while (next_delay == 0); - return current_ev; + ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); } - -int ieee80211_scan_results(struct ieee80211_local *local, - struct iw_request_info *info, - char *buf, size_t len) +int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, + struct cfg80211_scan_request *req) { - char *current_ev = buf; - char *end_buf = buf + len; - struct ieee80211_bss *bss; + int res; - spin_lock_bh(&local->bss_lock); - list_for_each_entry(bss, &local->bss_list, list) { - if (buf + len - current_ev <= IW_EV_ADDR_LEN) { - spin_unlock_bh(&local->bss_lock); - return -E2BIG; + mutex_lock(&sdata->local->scan_mtx); + res = __ieee80211_start_scan(sdata, req); + mutex_unlock(&sdata->local->scan_mtx); + + return res; +} + +int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, + const u8 *ssid, u8 ssid_len, + struct ieee80211_channel *chan) +{ + struct ieee80211_local *local = sdata->local; + int ret = -EBUSY; + enum nl80211_band band; + + mutex_lock(&local->scan_mtx); + + /* busy scanning */ + if (local->scan_req) + goto unlock; + + /* fill internal scan request */ + if (!chan) { + int i, nchan = 0; + + for (band = 0; band < IEEE80211_NUM_BANDS; band++) { + if (!local->hw.wiphy->bands[band]) + continue; + for (i = 0; + i < local->hw.wiphy->bands[band]->n_channels; + i++) { + local->int_scan_req->channels[nchan] = + &local->hw.wiphy->bands[band]->channels[i]; + nchan++; + } } - current_ev = ieee80211_scan_result(local, info, bss, - current_ev, end_buf); + + local->int_scan_req->n_channels = nchan; + } else { + local->int_scan_req->channels[0] = chan; + local->int_scan_req->n_channels = 1; } - spin_unlock_bh(&local->bss_lock); - return current_ev - buf; + + local->int_scan_req->ssids = &local->scan_ssid; + local->int_scan_req->n_ssids = 1; + memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); + local->int_scan_req->ssids[0].ssid_len = ssid_len; + + ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); + unlock: + mutex_unlock(&local->scan_mtx); + return ret; +} + +void ieee80211_scan_cancel(struct ieee80211_local *local) +{ + bool abortscan; + + cancel_delayed_work_sync(&local->scan_work); + + /* + * Only call this function when a scan can't be + * queued -- mostly at suspend under RTNL. + */ + mutex_lock(&local->scan_mtx); + abortscan = test_bit(SCAN_SW_SCANNING, &local->scanning) || + (!local->scanning && local->scan_req); + mutex_unlock(&local->scan_mtx); + + if (abortscan) + ieee80211_scan_completed(&local->hw, true); }