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-rw-r--r--net/mac80211/scan.c553
1 files changed, 553 insertions, 0 deletions
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
new file mode 100644
index 00000000000..68fa782acd7
--- /dev/null
+++ b/net/mac80211/scan.c
@@ -0,0 +1,553 @@
+/*
+ * BSS client mode implementation
+ * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
+ * Copyright 2004, Instant802 Networks, Inc.
+ * Copyright 2005, Devicescape Software, Inc.
+ * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/wireless.h>
+#include <linux/if_arp.h>
+#include <net/mac80211.h>
+#include <net/iw_handler.h>
+
+#include "ieee80211_i.h"
+
+#define IEEE80211_PROBE_DELAY (HZ / 33)
+#define IEEE80211_CHANNEL_TIME (HZ / 33)
+#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
+
+
+static void ieee80211_send_nullfunc(struct ieee80211_local *local,
+ struct ieee80211_sub_if_data *sdata,
+ int powersave)
+{
+ struct sk_buff *skb;
+ struct ieee80211_hdr *nullfunc;
+ __le16 fc;
+
+ 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_sta_tx(sdata, skb, 0);
+}
+
+static void ieee80211_restart_sta_timer(struct ieee80211_sub_if_data *sdata)
+{
+ if (sdata->vif.type == IEEE80211_IF_TYPE_STA ||
+ ieee80211_vif_is_mesh(&sdata->vif))
+ ieee80211_sta_timer((unsigned long)sdata);
+}
+
+void ieee80211_scan_completed(struct ieee80211_hw *hw)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_sub_if_data *sdata;
+ union iwreq_data wrqu;
+
+ local->last_scan_completed = jiffies;
+ memset(&wrqu, 0, sizeof(wrqu));
+ wireless_send_event(local->scan_sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
+
+ if (local->sta_hw_scanning) {
+ local->sta_hw_scanning = 0;
+ if (ieee80211_hw_config(local))
+ printk(KERN_DEBUG "%s: failed to restore operational "
+ "channel after scan\n", wiphy_name(local->hw.wiphy));
+ /* Restart STA timer for HW scan case */
+ rcu_read_lock();
+ list_for_each_entry_rcu(sdata, &local->interfaces, list)
+ ieee80211_restart_sta_timer(sdata);
+ rcu_read_unlock();
+
+ goto done;
+ }
+
+ local->sta_sw_scanning = 0;
+ if (ieee80211_hw_config(local))
+ printk(KERN_DEBUG "%s: failed to restore operational "
+ "channel after scan\n", wiphy_name(local->hw.wiphy));
+
+
+ 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);
+
+ netif_addr_unlock(local->mdev);
+ netif_tx_unlock_bh(local->mdev);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+ /* Tell AP we're back */
+ if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
+ 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);
+
+ ieee80211_restart_sta_timer(sdata);
+ }
+ rcu_read_unlock();
+
+ done:
+ ieee80211_mlme_notify_scan_completed(local);
+}
+EXPORT_SYMBOL(ieee80211_scan_completed);
+
+
+void ieee80211_sta_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;
+ struct ieee80211_supported_band *sband;
+ struct ieee80211_channel *chan;
+ int skip;
+ unsigned long next_delay = 0;
+
+ if (!local->sta_sw_scanning)
+ return;
+
+ 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;
+
+ /*
+ * 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;
+ }
+
+ /* 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 == IEEE80211_IF_TYPE_IBSS &&
+ chan->flags & IEEE80211_CHAN_NO_IBSS))
+ skip = 1;
+
+ if (!skip) {
+ local->scan_channel = chan;
+ if (ieee80211_hw_config(local)) {
+ printk(KERN_DEBUG "%s: failed to set freq to "
+ "%d MHz for scan\n", wiphy_name(local->hw.wiphy),
+ chan->center_freq);
+ skip = 1;
+ }
+ }
+
+ /* 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;
+ }
+
+ if (skip)
+ break;
+
+ 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;
+
+ 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;
+ }
+
+ if (local->sta_sw_scanning)
+ queue_delayed_work(local->hw.workqueue, &local->scan_work,
+ next_delay);
+}
+
+
+int ieee80211_sta_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;
+
+ 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
+ */
+
+ /* MLME-SCAN.confirm
+ * BSSDescriptionSet
+ * ResultCode: SUCCESS, INVALID_PARAMETERS
+ */
+
+ if (local->sta_sw_scanning || local->sta_hw_scanning) {
+ if (local->scan_sdata == scan_sdata)
+ return 0;
+ return -EBUSY;
+ }
+
+ if (local->ops->hw_scan) {
+ int rc = local->ops->hw_scan(local_to_hw(local),
+ ssid, ssid_len);
+ if (!rc) {
+ local->sta_hw_scanning = 1;
+ local->scan_sdata = scan_sdata;
+ }
+ return rc;
+ }
+
+ local->sta_sw_scanning = 1;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+ if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
+ if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
+ netif_tx_stop_all_queues(sdata->dev);
+ ieee80211_send_nullfunc(local, sdata, 1);
+ }
+ } else
+ netif_tx_stop_all_queues(sdata->dev);
+ }
+ rcu_read_unlock();
+
+ 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);
+
+ return 0;
+}
+
+
+int ieee80211_sta_req_scan(struct ieee80211_sub_if_data *sdata, u8 *ssid, size_t ssid_len)
+{
+ struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+ struct ieee80211_local *local = sdata->local;
+
+ if (sdata->vif.type != IEEE80211_IF_TYPE_STA)
+ return ieee80211_sta_start_scan(sdata, ssid, ssid_len);
+
+ if (local->sta_sw_scanning || local->sta_hw_scanning) {
+ if (local->scan_sdata == sdata)
+ return 0;
+ return -EBUSY;
+ }
+
+ 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);
+ return 0;
+}
+
+
+static void ieee80211_sta_add_scan_ies(struct iw_request_info *info,
+ struct ieee80211_sta_bss *bss,
+ char **current_ev, char *end_buf)
+{
+ u8 *pos, *end, *next;
+ struct iw_event iwe;
+
+ if (bss == NULL || bss->ies == NULL)
+ return;
+
+ /*
+ * If needed, fragment the IEs buffer (at IE boundaries) into short
+ * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
+ */
+ pos = bss->ies;
+ end = pos + bss->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(info, *current_ev,
+ end_buf, &iwe, pos);
+
+ 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(info, *current_ev,
+ end_buf, &iwe, pos);
+ }
+}
+
+
+static char *
+ieee80211_sta_scan_result(struct ieee80211_local *local,
+ struct iw_request_info *info,
+ struct ieee80211_sta_bss *bss,
+ char *current_ev, char *end_buf)
+{
+ 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);
+ }
+
+ 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);
+ }
+
+ 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_sta_add_scan_ies(info, bss, &current_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;
+ }
+
+ 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);
+ }
+
+ 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);
+ }
+ }
+
+ return current_ev;
+}
+
+
+int ieee80211_sta_scan_results(struct ieee80211_local *local,
+ struct iw_request_info *info,
+ char *buf, size_t len)
+{
+ char *current_ev = buf;
+ char *end_buf = buf + len;
+ struct ieee80211_sta_bss *bss;
+
+ spin_lock_bh(&local->sta_bss_lock);
+ list_for_each_entry(bss, &local->sta_bss_list, list) {
+ if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
+ spin_unlock_bh(&local->sta_bss_lock);
+ return -E2BIG;
+ }
+ current_ev = ieee80211_sta_scan_result(local, info, bss,
+ current_ev, end_buf);
+ }
+ spin_unlock_bh(&local->sta_bss_lock);
+ return current_ev - buf;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-20 00:45:14 +0000