816 lines
22 KiB
C
816 lines
22 KiB
C
/*
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* Scanning implementation
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*
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* Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
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* Copyright 2004, Instant802 Networks, Inc.
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* Copyright 2005, Devicescape Software, Inc.
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* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
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* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/wireless.h>
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#include <linux/if_arp.h>
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#include <linux/rtnetlink.h>
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#include <net/mac80211.h>
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#include "ieee80211_i.h"
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#include "driver-ops.h"
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#include "mesh.h"
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#define IEEE80211_PROBE_DELAY (HZ / 33)
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#define IEEE80211_CHANNEL_TIME (HZ / 33)
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#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8)
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struct ieee80211_bss *
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ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
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u8 *ssid, u8 ssid_len)
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{
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return (void *)cfg80211_get_bss(local->hw.wiphy,
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ieee80211_get_channel(local->hw.wiphy,
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freq),
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bssid, ssid, ssid_len,
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0, 0);
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}
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static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss)
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{
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struct ieee80211_bss *bss = (void *)cbss;
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kfree(bss_mesh_id(bss));
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kfree(bss_mesh_cfg(bss));
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}
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void ieee80211_rx_bss_put(struct ieee80211_local *local,
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struct ieee80211_bss *bss)
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{
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cfg80211_put_bss((struct cfg80211_bss *)bss);
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}
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struct ieee80211_bss *
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ieee80211_bss_info_update(struct ieee80211_local *local,
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struct ieee80211_rx_status *rx_status,
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struct ieee80211_mgmt *mgmt,
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size_t len,
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struct ieee802_11_elems *elems,
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struct ieee80211_channel *channel,
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bool beacon)
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{
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struct ieee80211_bss *bss;
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int clen;
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s32 signal = 0;
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if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
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signal = rx_status->signal * 100;
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else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
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signal = (rx_status->signal * 100) / local->hw.max_signal;
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bss = (void *)cfg80211_inform_bss_frame(local->hw.wiphy, channel,
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mgmt, len, signal, GFP_ATOMIC);
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if (!bss)
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return NULL;
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bss->cbss.free_priv = ieee80211_rx_bss_free;
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/* save the ERP value so that it is available at association time */
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if (elems->erp_info && elems->erp_info_len >= 1) {
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bss->erp_value = elems->erp_info[0];
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bss->has_erp_value = 1;
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}
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if (elems->tim) {
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struct ieee80211_tim_ie *tim_ie =
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(struct ieee80211_tim_ie *)elems->tim;
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bss->dtim_period = tim_ie->dtim_period;
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}
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/* set default value for buggy AP/no TIM element */
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if (bss->dtim_period == 0)
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bss->dtim_period = 1;
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bss->supp_rates_len = 0;
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if (elems->supp_rates) {
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clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
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if (clen > elems->supp_rates_len)
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clen = elems->supp_rates_len;
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memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates,
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clen);
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bss->supp_rates_len += clen;
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}
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if (elems->ext_supp_rates) {
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clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
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if (clen > elems->ext_supp_rates_len)
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clen = elems->ext_supp_rates_len;
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memcpy(&bss->supp_rates[bss->supp_rates_len],
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elems->ext_supp_rates, clen);
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bss->supp_rates_len += clen;
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}
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bss->wmm_used = elems->wmm_param || elems->wmm_info;
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if (!beacon)
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bss->last_probe_resp = jiffies;
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return bss;
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}
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ieee80211_rx_result
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ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
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{
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struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
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struct ieee80211_mgmt *mgmt;
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struct ieee80211_bss *bss;
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u8 *elements;
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struct ieee80211_channel *channel;
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size_t baselen;
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int freq;
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__le16 fc;
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bool presp, beacon = false;
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struct ieee802_11_elems elems;
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if (skb->len < 2)
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return RX_DROP_UNUSABLE;
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mgmt = (struct ieee80211_mgmt *) skb->data;
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fc = mgmt->frame_control;
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if (ieee80211_is_ctl(fc))
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return RX_CONTINUE;
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if (skb->len < 24)
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return RX_DROP_MONITOR;
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presp = ieee80211_is_probe_resp(fc);
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if (presp) {
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/* ignore ProbeResp to foreign address */
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if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
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return RX_DROP_MONITOR;
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presp = true;
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elements = mgmt->u.probe_resp.variable;
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baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
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} else {
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beacon = ieee80211_is_beacon(fc);
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baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
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elements = mgmt->u.beacon.variable;
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}
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if (!presp && !beacon)
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return RX_CONTINUE;
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if (baselen > skb->len)
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return RX_DROP_MONITOR;
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ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
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if (elems.ds_params && elems.ds_params_len == 1)
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freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
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else
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freq = rx_status->freq;
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channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
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if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
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return RX_DROP_MONITOR;
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bss = ieee80211_bss_info_update(sdata->local, rx_status,
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mgmt, skb->len, &elems,
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channel, beacon);
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if (bss)
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ieee80211_rx_bss_put(sdata->local, bss);
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dev_kfree_skb(skb);
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return RX_QUEUED;
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}
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/* return false if no more work */
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static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
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{
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struct cfg80211_scan_request *req = local->scan_req;
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enum ieee80211_band band;
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int i, ielen, n_chans;
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do {
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if (local->hw_scan_band == IEEE80211_NUM_BANDS)
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return false;
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band = local->hw_scan_band;
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n_chans = 0;
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for (i = 0; i < req->n_channels; i++) {
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if (req->channels[i]->band == band) {
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local->hw_scan_req->channels[n_chans] =
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req->channels[i];
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n_chans++;
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}
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}
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local->hw_scan_band++;
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} while (!n_chans);
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local->hw_scan_req->n_channels = n_chans;
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ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie,
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req->ie, req->ie_len, band);
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local->hw_scan_req->ie_len = ielen;
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return true;
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}
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/*
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* inform AP that we will go to sleep so that it will buffer the frames
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* while we scan
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*/
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static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata)
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{
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struct ieee80211_local *local = sdata->local;
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local->scan_ps_enabled = false;
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/* FIXME: what to do when local->pspolling is true? */
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del_timer_sync(&local->dynamic_ps_timer);
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cancel_work_sync(&local->dynamic_ps_enable_work);
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if (local->hw.conf.flags & IEEE80211_CONF_PS) {
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local->scan_ps_enabled = true;
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local->hw.conf.flags &= ~IEEE80211_CONF_PS;
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ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
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}
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if (!(local->scan_ps_enabled) ||
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!(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))
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/*
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* If power save was enabled, no need to send a nullfunc
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* frame because AP knows that we are sleeping. But if the
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* hardware is creating the nullfunc frame for power save
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* status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
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* enabled) and power save was enabled, the firmware just
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* sent a null frame with power save disabled. So we need
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* to send a new nullfunc frame to inform the AP that we
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* are again sleeping.
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*/
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ieee80211_send_nullfunc(local, sdata, 1);
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}
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/* inform AP that we are awake again, unless power save is enabled */
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static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata)
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{
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struct ieee80211_local *local = sdata->local;
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if (!local->ps_sdata)
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ieee80211_send_nullfunc(local, sdata, 0);
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else if (local->scan_ps_enabled) {
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/*
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* In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
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* will send a nullfunc frame with the powersave bit set
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* even though the AP already knows that we are sleeping.
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* This could be avoided by sending a null frame with power
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* save bit disabled before enabling the power save, but
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* this doesn't gain anything.
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*
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* When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
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* to send a nullfunc frame because AP already knows that
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* we are sleeping, let's just enable power save mode in
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* hardware.
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*/
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local->hw.conf.flags |= IEEE80211_CONF_PS;
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ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
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} else if (local->hw.conf.dynamic_ps_timeout > 0) {
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/*
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* If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
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* had been running before leaving the operating channel,
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* restart the timer now and send a nullfunc frame to inform
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* the AP that we are awake.
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*/
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ieee80211_send_nullfunc(local, sdata, 0);
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mod_timer(&local->dynamic_ps_timer, jiffies +
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msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
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}
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}
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void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
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{
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struct ieee80211_local *local = hw_to_local(hw);
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struct ieee80211_sub_if_data *sdata;
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bool was_hw_scan;
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mutex_lock(&local->scan_mtx);
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/*
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* It's ok to abort a not-yet-running scan (that
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* we have one at all will be verified by checking
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* local->scan_req next), but not to complete it
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* successfully.
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*/
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if (WARN_ON(!local->scanning && !aborted))
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aborted = true;
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if (WARN_ON(!local->scan_req)) {
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mutex_unlock(&local->scan_mtx);
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return;
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}
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was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
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if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) {
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ieee80211_queue_delayed_work(&local->hw,
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&local->scan_work, 0);
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mutex_unlock(&local->scan_mtx);
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return;
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}
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kfree(local->hw_scan_req);
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local->hw_scan_req = NULL;
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if (local->scan_req != local->int_scan_req)
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cfg80211_scan_done(local->scan_req, aborted);
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local->scan_req = NULL;
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local->scan_sdata = NULL;
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local->scanning = 0;
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local->scan_channel = NULL;
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/* we only have to protect scan_req and hw/sw scan */
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mutex_unlock(&local->scan_mtx);
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ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
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if (was_hw_scan)
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goto done;
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ieee80211_configure_filter(local);
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drv_sw_scan_complete(local);
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mutex_lock(&local->iflist_mtx);
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list_for_each_entry(sdata, &local->interfaces, list) {
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if (!netif_running(sdata->dev))
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continue;
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/* Tell AP we're back */
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if (sdata->vif.type == NL80211_IFTYPE_STATION) {
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if (sdata->u.mgd.associated) {
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ieee80211_scan_ps_disable(sdata);
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netif_tx_wake_all_queues(sdata->dev);
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}
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} else
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netif_tx_wake_all_queues(sdata->dev);
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/* re-enable beaconing */
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if (sdata->vif.type == NL80211_IFTYPE_AP ||
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sdata->vif.type == NL80211_IFTYPE_ADHOC ||
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sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
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ieee80211_bss_info_change_notify(
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sdata, BSS_CHANGED_BEACON_ENABLED);
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}
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mutex_unlock(&local->iflist_mtx);
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done:
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ieee80211_recalc_idle(local);
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ieee80211_mlme_notify_scan_completed(local);
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ieee80211_ibss_notify_scan_completed(local);
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ieee80211_mesh_notify_scan_completed(local);
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}
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EXPORT_SYMBOL(ieee80211_scan_completed);
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static int ieee80211_start_sw_scan(struct ieee80211_local *local)
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{
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struct ieee80211_sub_if_data *sdata;
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/*
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* Hardware/driver doesn't support hw_scan, so use software
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* scanning instead. First send a nullfunc frame with power save
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* bit on so that AP will buffer the frames for us while we are not
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* listening, then send probe requests to each channel and wait for
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* the responses. After all channels are scanned, tune back to the
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* original channel and send a nullfunc frame with power save bit
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* off to trigger the AP to send us all the buffered frames.
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*
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* Note that while local->sw_scanning is true everything else but
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* nullfunc frames and probe requests will be dropped in
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* ieee80211_tx_h_check_assoc().
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*/
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drv_sw_scan_start(local);
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mutex_lock(&local->iflist_mtx);
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list_for_each_entry(sdata, &local->interfaces, list) {
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if (!netif_running(sdata->dev))
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continue;
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/* disable beaconing */
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if (sdata->vif.type == NL80211_IFTYPE_AP ||
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sdata->vif.type == NL80211_IFTYPE_ADHOC ||
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sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
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ieee80211_bss_info_change_notify(
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sdata, BSS_CHANGED_BEACON_ENABLED);
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/*
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* only handle non-STA interfaces here, STA interfaces
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* are handled in the scan state machine
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*/
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if (sdata->vif.type != NL80211_IFTYPE_STATION)
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netif_tx_stop_all_queues(sdata->dev);
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}
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mutex_unlock(&local->iflist_mtx);
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local->next_scan_state = SCAN_DECISION;
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local->scan_channel_idx = 0;
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ieee80211_configure_filter(local);
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/* TODO: start scan as soon as all nullfunc frames are ACKed */
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ieee80211_queue_delayed_work(&local->hw,
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&local->scan_work,
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IEEE80211_CHANNEL_TIME);
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return 0;
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}
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static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
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struct cfg80211_scan_request *req)
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{
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struct ieee80211_local *local = sdata->local;
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struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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int rc;
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if (local->scan_req)
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return -EBUSY;
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if (req != local->int_scan_req &&
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sdata->vif.type == NL80211_IFTYPE_STATION &&
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!list_empty(&ifmgd->work_list)) {
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/* actually wait for the work it's doing to finish/time out */
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set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request);
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local->scan_req = req;
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local->scan_sdata = sdata;
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return 0;
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}
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if (local->ops->hw_scan) {
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u8 *ies;
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local->hw_scan_req = kmalloc(
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sizeof(*local->hw_scan_req) +
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req->n_channels * sizeof(req->channels[0]) +
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2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len +
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req->ie_len, GFP_KERNEL);
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if (!local->hw_scan_req)
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return -ENOMEM;
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local->hw_scan_req->ssids = req->ssids;
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local->hw_scan_req->n_ssids = req->n_ssids;
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ies = (u8 *)local->hw_scan_req +
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sizeof(*local->hw_scan_req) +
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req->n_channels * sizeof(req->channels[0]);
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local->hw_scan_req->ie = ies;
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local->hw_scan_band = 0;
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}
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local->scan_req = req;
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local->scan_sdata = sdata;
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if (local->ops->hw_scan)
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__set_bit(SCAN_HW_SCANNING, &local->scanning);
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else
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__set_bit(SCAN_SW_SCANNING, &local->scanning);
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/*
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* Kicking off the scan need not be protected,
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* only the scan variable stuff, since now
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* local->scan_req is assigned and other callers
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* will abort their scan attempts.
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*
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* This avoids getting a scan_mtx -> iflist_mtx
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* dependency, so that the scan completed calls
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|
* have more locking freedom.
|
|
*/
|
|
|
|
ieee80211_recalc_idle(local);
|
|
mutex_unlock(&local->scan_mtx);
|
|
|
|
if (local->ops->hw_scan) {
|
|
WARN_ON(!ieee80211_prep_hw_scan(local));
|
|
rc = drv_hw_scan(local, local->hw_scan_req);
|
|
} else
|
|
rc = ieee80211_start_sw_scan(local);
|
|
|
|
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;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int ieee80211_scan_state_decision(struct ieee80211_local *local,
|
|
unsigned long *next_delay)
|
|
{
|
|
bool associated = false;
|
|
struct ieee80211_sub_if_data *sdata;
|
|
|
|
/* 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 */
|
|
mutex_lock(&local->iflist_mtx);
|
|
list_for_each_entry(sdata, &local->interfaces, list) {
|
|
if (!netif_running(sdata->dev))
|
|
continue;
|
|
|
|
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
|
|
if (sdata->u.mgd.associated) {
|
|
associated = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
mutex_unlock(&local->iflist_mtx);
|
|
|
|
if (local->scan_channel) {
|
|
/*
|
|
* we're currently scanning a different channel, let's
|
|
* switch back to the operating channel now if at least
|
|
* one interface is associated. Otherwise just scan the
|
|
* next channel
|
|
*/
|
|
if (associated)
|
|
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;
|
|
}
|
|
|
|
static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local,
|
|
unsigned long *next_delay)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata;
|
|
|
|
/*
|
|
* notify the AP about us leaving the channel and stop all STA interfaces
|
|
*/
|
|
mutex_lock(&local->iflist_mtx);
|
|
list_for_each_entry(sdata, &local->interfaces, list) {
|
|
if (!netif_running(sdata->dev))
|
|
continue;
|
|
|
|
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
|
|
netif_tx_stop_all_queues(sdata->dev);
|
|
if (sdata->u.mgd.associated)
|
|
ieee80211_scan_ps_enable(sdata);
|
|
}
|
|
}
|
|
mutex_unlock(&local->iflist_mtx);
|
|
|
|
__set_bit(SCAN_OFF_CHANNEL, &local->scanning);
|
|
|
|
/* advance to the next channel to be scanned */
|
|
*next_delay = HZ / 10;
|
|
local->next_scan_state = SCAN_SET_CHANNEL;
|
|
}
|
|
|
|
static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local,
|
|
unsigned long *next_delay)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = local->scan_sdata;
|
|
|
|
/* switch back to the operating channel */
|
|
local->scan_channel = NULL;
|
|
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
|
|
|
|
/*
|
|
* notify the AP about us being back and restart all STA interfaces
|
|
*/
|
|
mutex_lock(&local->iflist_mtx);
|
|
list_for_each_entry(sdata, &local->interfaces, list) {
|
|
if (!netif_running(sdata->dev))
|
|
continue;
|
|
|
|
/* Tell AP we're back */
|
|
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
|
|
if (sdata->u.mgd.associated)
|
|
ieee80211_scan_ps_disable(sdata);
|
|
netif_tx_wake_all_queues(sdata->dev);
|
|
}
|
|
}
|
|
mutex_unlock(&local->iflist_mtx);
|
|
|
|
__clear_bit(SCAN_OFF_CHANNEL, &local->scanning);
|
|
|
|
*next_delay = HZ / 5;
|
|
local->next_scan_state = SCAN_DECISION;
|
|
}
|
|
|
|
static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
|
|
unsigned long *next_delay)
|
|
{
|
|
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;
|
|
|
|
/* 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;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
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;
|
|
}
|
|
|
|
/* active scan, send probes */
|
|
*next_delay = IEEE80211_PROBE_DELAY;
|
|
local->next_scan_state = SCAN_SEND_PROBE;
|
|
}
|
|
|
|
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;
|
|
|
|
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);
|
|
|
|
/*
|
|
* After sending probe requests, wait for probe responses
|
|
* on the channel.
|
|
*/
|
|
*next_delay = IEEE80211_CHANNEL_TIME;
|
|
local->next_scan_state = SCAN_DECISION;
|
|
}
|
|
|
|
void ieee80211_scan_work(struct work_struct *work)
|
|
{
|
|
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 (local->hw_scan_req) {
|
|
int rc = drv_hw_scan(local, local->hw_scan_req);
|
|
mutex_unlock(&local->scan_mtx);
|
|
if (rc)
|
|
ieee80211_scan_completed(&local->hw, true);
|
|
return;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
mutex_unlock(&local->scan_mtx);
|
|
|
|
/*
|
|
* Avoid re-scheduling when the sdata is going away.
|
|
*/
|
|
if (!netif_running(sdata->dev)) {
|
|
ieee80211_scan_completed(&local->hw, true);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
|
|
}
|
|
|
|
int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
|
|
struct cfg80211_scan_request *req)
|
|
{
|
|
int res;
|
|
|
|
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_local *local = sdata->local;
|
|
int ret = -EBUSY;
|
|
|
|
mutex_lock(&local->scan_mtx);
|
|
|
|
/* busy scanning */
|
|
if (local->scan_req)
|
|
goto unlock;
|
|
|
|
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);
|
|
}
|