[PATCH 3/4] hostapd: add survey dump support
Luis R. Rodriguez
lrodriguez
Wed Jun 22 20:50:52 PDT 2011
This adds survey dump support for all frequencies
and for specific desired frequencies. This will later
be used by ACS code for spectrum heuristics.
Signed-off-by: Luis R. Rodriguez <lrodriguez at atheros.com>
---
src/ap/ap_drv_ops.h | 15 +++
src/ap/drv_callbacks.c | 72 +++++++++++++++-
src/ap/hostapd.h | 8 ++
src/drivers/driver.h | 89 +++++++++++++++++++-
src/drivers/driver_nl80211.c | 193 ++++++++++++++++++++++++++++++++++++++++++
5 files changed, 375 insertions(+), 2 deletions(-)
diff --git a/src/ap/ap_drv_ops.h b/src/ap/ap_drv_ops.h
index a62e1e5..24c7e95 100644
--- a/src/ap/ap_drv_ops.h
+++ b/src/ap/ap_drv_ops.h
@@ -213,4 +213,19 @@ static inline int hostapd_drv_remain_on_channel(struct hostapd_data *hapd,
return hapd->driver->remain_on_channel(hapd->drv_priv, freq, duration);
}
+static inline int hostapd_drv_survey_freq(struct hostapd_data *hapd,
+ unsigned int freq)
+{
+ if (hapd->driver == NULL)
+ return -1;
+ if (!hapd->driver->get_survey)
+ return -1;
+ return hapd->driver->get_survey(hapd->drv_priv, freq);
+}
+
+static inline int hostapd_drv_survey(struct hostapd_data *hapd)
+{
+ return hostapd_drv_survey_freq(hapd, 0);
+}
+
#endif /* AP_DRV_OPS */
diff --git a/src/ap/drv_callbacks.c b/src/ap/drv_callbacks.c
index 676fac1..6953b71 100644
--- a/src/ap/drv_callbacks.c
+++ b/src/ap/drv_callbacks.c
@@ -545,6 +545,73 @@ static void hostapd_event_roc_cancel(struct hostapd_data *hapd,
/* XXX: pass err to listeners, no one yet */
}
+struct hostapd_channel_data *hostapd_get_mode_channel(struct hostapd_iface *iface,
+ unsigned int freq)
+{
+ unsigned int i;
+ struct hostapd_channel_data *chan;
+
+ for (i = 0; i < iface->current_mode->num_channels; i++) {
+ chan = &iface->current_mode->channels[i];
+ if (!chan)
+ return NULL;
+ if (chan->freq == freq)
+ return chan;
+ }
+
+ return NULL;
+}
+
+static void hostapd_update_nf(struct hostapd_iface *iface,
+ struct hostapd_channel_data *chan,
+ struct freq_survey *survey)
+{
+ if (!iface->chans_surveyed) {
+ chan->min_nf = survey->nf;
+ iface->lowest_nf = survey->nf;
+ } else {
+ if (!chan->survey_count)
+ chan->min_nf = survey->nf;
+ else if (survey->nf < chan->min_nf)
+ chan->min_nf = survey->nf;
+ if (survey->nf < iface->lowest_nf)
+ iface->lowest_nf = survey->nf;
+ }
+}
+
+static void hostapd_event_get_survey(struct hostapd_data *hapd,
+ struct survey_results *survey_results)
+{
+ struct hostapd_iface *iface = hapd->iface;
+ struct freq_survey *survey, *tmp;
+ struct hostapd_channel_data *chan;
+
+ if (dl_list_empty(&survey_results->survey_list)) {
+ wpa_printf(MSG_DEBUG, "ACS: no survey data received");
+ return;
+ }
+
+ dl_list_for_each_safe(survey, tmp, &survey_results->survey_list, struct freq_survey, list_member) {
+ chan = hostapd_get_mode_channel(iface, survey->freq);
+ if (!chan)
+ goto fail;
+ if (chan->flag & HOSTAPD_CHAN_DISABLED)
+ continue;
+
+ dl_list_del(&survey->list_member);
+ dl_list_add_tail(&chan->survey_list, &survey->list_member);
+
+ hostapd_update_nf(iface, chan, survey);
+
+ chan->survey_count++;
+ iface->chans_surveyed++;
+ }
+
+ return;
+fail:
+ iface->chans_surveyed = 0;
+}
+
void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
union wpa_event_data *data)
{
@@ -633,6 +700,7 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
data->rx_action.bssid == NULL)
break;
hostapd_rx_action(hapd, &data->rx_action);
+#endif /* NEED_AP_MLME */
case EVENT_REMAIN_ON_CHANNEL:
hostapd_event_roc(hapd,
data->remain_on_channel.freq,
@@ -643,7 +711,9 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
data->remain_on_channel.freq,
data->remain_on_channel.duration);
break;
-#endif /* NEED_AP_MLME */
+ case EVENT_SURVEY:
+ hostapd_event_get_survey(hapd, &data->survey_results);
+ break;
default:
wpa_printf(MSG_DEBUG, "Unknown event %d", event);
break;
diff --git a/src/ap/hostapd.h b/src/ap/hostapd.h
index d8318ee..1095d2b 100644
--- a/src/ap/hostapd.h
+++ b/src/ap/hostapd.h
@@ -231,6 +231,14 @@ struct hostapd_iface {
/* Offchannel operation helper */
unsigned int off_channel_freq_idx;
+ /* surveying helpers */
+
+ /* number of channels surveyed */
+ unsigned int chans_surveyed;
+
+ /* lowest observed noise floor in dBm */
+ s8 lowest_nf;
+
void (*scan_cb)(struct hostapd_iface *iface);
int (*ctrl_iface_init)(struct hostapd_data *hapd);
diff --git a/src/drivers/driver.h b/src/drivers/driver.h
index 513580a..0e1c5c1 100644
--- a/src/drivers/driver.h
+++ b/src/drivers/driver.h
@@ -26,6 +26,7 @@
#define WPA_SUPPLICANT_DRIVER_VERSION 4
#include "common/defs.h"
+#include "list.h"
#define HOSTAPD_CHAN_DISABLED 0x00000001
#define HOSTAPD_CHAN_PASSIVE_SCAN 0x00000002
@@ -58,6 +59,22 @@ struct hostapd_channel_data {
* max_tx_power - maximum transmit power in dBm
*/
u8 max_tx_power;
+
+ /*
+ * survey_count - number of surveys XXX: can we remove this and use the count of the linked list?
+ */
+ unsigned int survey_count;
+
+ /*
+ * survey_list - linked list of surveys
+ */
+ struct dl_list survey_list;
+
+ /**
+ * min_nf - minimum observed noise floor, in dBm, based on all surveyed channel data
+ */
+ s8 min_nf;
+
};
/**
@@ -2253,6 +2270,30 @@ struct wpa_driver_ops {
* implementation, there is no need to implement this function.
*/
int (*set_authmode)(void *priv, int authmode);
+
+ /**
+ * get_survey - Retrieve survey data
+ * @priv: Private driver interface data
+ * @freq: if set survey data for the specified frequency is only
+ * being requested. If not set all survey data is requested.
+ * Returns: 0 on success, -1 on failure
+ *
+ * Use this to retreieve:
+ *
+ * - the observed channel noise floor
+ * - the amount of time we have spent on the channel
+ * - the amount of time during which we have spent on the channel that
+ * the radio has determined the the medium is busy and we cannot transmit
+ * - the amount of time we have spent RX'ing data
+ * - the amount of time we have spent TX'ing data
+ *
+ * This data can be use for spectrum heuristics, one example is
+ * Automatic Channel Selection (ACS). The channel survey data is
+ * kept on a linked list on the channel data, one entry is added
+ * for each survey. The min_nf of the channel is updated for
+ * each survey.
+ */
+ int (*get_survey)(void *priv, unsigned int freq);
};
@@ -2655,9 +2696,44 @@ enum wpa_event_type {
/**
* EVENT_IBSS_PEER_LOST - IBSS peer not reachable anymore
*/
- EVENT_IBSS_PEER_LOST
+ EVENT_IBSS_PEER_LOST,
+
+ /**
+ * EVENT_SURVEY - Received survey data
+ *
+ * This event gets triggered when a driver query is issued for survey
+ * data and its returned. The returned data is stored in
+ * struct survey_results. The results provide at most one survey
+ * entry for each frequency and at minimum will provide survey
+ * one survey entry for one frequency. The survey data can be
+ * os_malloc()'d and then os_free()'d, so the event callback must
+ * only copy data.
+ */
+ EVENT_SURVEY,
};
+/**
+ * struct survey_info - channel survey info
+ *
+ * @ifidx: interface index in which this survey was observed
+ * @freq: center of frequency of the surveyed channel
+ * @nf: channel noise floor in dBm
+ * @channel_time: amount of time in ms the radio spent on the channel
+ * @channel_time_busy: amount of time in ms the radio detected some signal
+ * that indicated to the radio the channel was not clear
+ * @channel_time_rx: amount of time the radio spent receiving data
+ * @channel_time_tx: amount of time the radio spent transmitting data
+ */
+struct freq_survey {
+ u32 ifidx;
+ unsigned int freq;
+ s8 nf;
+ u64 channel_time;
+ u64 channel_time_busy;
+ u64 channel_time_rx;
+ u64 channel_time_tx;
+ struct dl_list list_member;
+};
/**
* union wpa_event_data - Additional data for wpa_supplicant_event() calls
@@ -3187,6 +3263,17 @@ union wpa_event_data {
struct ibss_peer_lost {
u8 peer[ETH_ALEN];
} ibss_peer_lost;
+
+ /**
+ * survey_results - survey result data for EVENT_SURVEY
+ * @freq_filter: requested frequency survey filter, 0 if request
+ * was for all survey data
+ * @survey_list: linked list of survey data
+ */
+ struct survey_results {
+ unsigned int freq_filter;
+ struct dl_list survey_list;
+ } survey_results;
};
/**
diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index cfc9372..e5c4962 100644
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -6603,6 +6603,198 @@ static int nl80211_flush_pmkid(void *priv)
return nl80211_pmkid(bss, NL80211_CMD_FLUSH_PMKSA, NULL, NULL);
}
+static void clean_survey_results(struct survey_results *survey_results)
+{
+ struct freq_survey *survey, *tmp;
+
+ if (dl_list_empty(&survey_results->survey_list))
+ return;
+
+ dl_list_for_each_safe(survey, tmp, &survey_results->survey_list, struct freq_survey, list_member) {
+ dl_list_del(&survey->list_member);
+ os_free(survey);
+ }
+}
+
+static void add_survey(struct nlattr **sinfo, u32 ifidx, struct dl_list *survey_list)
+{
+ struct freq_survey *survey;
+
+ survey = (struct freq_survey*) os_malloc(sizeof(struct freq_survey));
+ if (!survey)
+ return;
+ os_memset(survey, 0, sizeof(struct freq_survey));
+
+ survey->ifidx = ifidx;
+ survey->freq = nla_get_u32(sinfo[NL80211_SURVEY_INFO_FREQUENCY]);
+ survey->nf = (int8_t) nla_get_u8(sinfo[NL80211_SURVEY_INFO_NOISE]);
+ survey->channel_time = nla_get_u64(sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME]);
+ survey->channel_time_busy = nla_get_u64(sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_BUSY]);
+ survey->channel_time_rx = nla_get_u64(sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_RX]);
+ survey->channel_time_tx = nla_get_u64(sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_TX]);
+
+ wpa_printf(MSG_DEBUG, "nl80211: Freq survey dump event (freq=%d MHz noise=%d "
+ "channel_time=%ld busy_time=%ld tx_time=%ld rx_time=%ld)",
+ survey->freq,
+ survey->nf,
+ survey->channel_time,
+ survey->channel_time_busy,
+ survey->channel_time_rx,
+ survey->channel_time_tx);
+
+ dl_list_add_tail(survey_list, &survey->list_member);
+}
+
+static int survey_check(struct nlattr **sinfo)
+{
+ if (!sinfo[NL80211_SURVEY_INFO_NOISE] ||
+ !sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME] ||
+ !sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_BUSY] ||
+ !sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_TX])
+ return 0;
+ return 1;
+}
+
+static void survey_fail_reason(struct nlattr **sinfo, u32 surveyed_freq)
+{
+ wpa_printf(MSG_ERROR,
+ "nl80211: Following survey data missing "
+ "for freq %d MHz:",
+ surveyed_freq);
+
+ if (!sinfo[NL80211_SURVEY_INFO_NOISE])
+ wpa_printf(MSG_ERROR, "\tnoise");
+
+ if (!sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME])
+ wpa_printf(MSG_ERROR, "\tchannel time");
+
+ if (!sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_BUSY])
+ wpa_printf(MSG_ERROR, "\tchannel busy time");
+
+ if (!sinfo[NL80211_SURVEY_INFO_CHANNEL_TIME_TX])
+ wpa_printf(MSG_ERROR, "\tchannel tx time");
+}
+
+static int check_survey_ok(struct nlattr **sinfo,
+ u32 surveyed_freq,
+ unsigned int freq_filter)
+{
+ int good_survey = survey_check(sinfo);
+
+ /* If no filter is specified we just drop data for any bogus survey */
+ if (!freq_filter) {
+ if (good_survey)
+ return 1;
+ /* No filter used but no usable survey data found */
+ survey_fail_reason(sinfo, surveyed_freq);
+ return 0;
+ }
+
+ if (freq_filter != surveyed_freq)
+ return 0;
+
+ if (good_survey)
+ return 1;
+ /* Filter matches now, lets be verbose why this is a bad survey */
+
+ survey_fail_reason(sinfo, surveyed_freq);
+ return 0;
+}
+
+static int survey_handler(struct nl_msg *msg, void *arg)
+{
+ struct nlattr *tb[NL80211_ATTR_MAX + 1];
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *sinfo[NL80211_SURVEY_INFO_MAX + 1];
+ struct survey_results *survey_results;
+ u32 surveyed_freq = 0;
+ u32 ifidx;
+
+ static struct nla_policy survey_policy[NL80211_SURVEY_INFO_MAX + 1] = {
+ [NL80211_SURVEY_INFO_FREQUENCY] = { .type = NLA_U32 },
+ [NL80211_SURVEY_INFO_NOISE] = { .type = NLA_U8 },
+ };
+
+ survey_results = (struct survey_results *) arg;
+
+ nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL);
+
+ ifidx = nla_get_u32(tb[NL80211_ATTR_IFINDEX]);
+
+ if (!tb[NL80211_ATTR_SURVEY_INFO])
+ return NL_SKIP;
+
+ if (nla_parse_nested(sinfo, NL80211_SURVEY_INFO_MAX,
+ tb[NL80211_ATTR_SURVEY_INFO],
+ survey_policy))
+ return NL_SKIP;
+
+ if (!sinfo[NL80211_SURVEY_INFO_FREQUENCY]) {
+ wpa_printf(MSG_ERROR, "nl80211: invalid survey data");
+ return NL_SKIP;
+ }
+
+ surveyed_freq = nla_get_u32(sinfo[NL80211_SURVEY_INFO_FREQUENCY]);
+
+ if (!check_survey_ok(sinfo, surveyed_freq, survey_results->freq_filter))
+ return NL_SKIP;
+
+ if (survey_results->freq_filter &&
+ survey_results->freq_filter != surveyed_freq) {
+ wpa_printf(MSG_EXCESSIVE, "nl80211: ignoring survey data "
+ "for freq %d MHz", surveyed_freq);
+ return NL_SKIP;
+ }
+
+ add_survey(sinfo, ifidx, &survey_results->survey_list);
+
+ return NL_SKIP;
+}
+
+static int wpa_driver_nl80211_get_survey(void *priv, unsigned int freq)
+{
+ struct i802_bss *bss = priv;
+ struct wpa_driver_nl80211_data *drv = bss->drv;
+ struct nl_msg *msg;
+ int err = -ENOBUFS;
+ union wpa_event_data data;
+ struct survey_results *survey_results;
+
+ os_memset(&data, 0, sizeof(data));
+ survey_results = &data.survey_results;
+
+ dl_list_init(&survey_results->survey_list);
+
+ msg = nlmsg_alloc();
+ if (!msg)
+ goto nla_put_failure;
+
+ genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0, NLM_F_DUMP,
+ NL80211_CMD_GET_SURVEY, 0);
+
+ NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, drv->ifindex);
+
+ if (freq)
+ data.survey_results.freq_filter = freq;
+
+ do {
+ err = send_and_recv_msgs(drv, msg, survey_handler, survey_results);
+ } while (err > 0);
+
+ if (err) {
+ wpa_printf(MSG_ERROR, "nl80211: failed to process survey data");
+ goto out_clean;
+ }
+
+ wpa_supplicant_event(drv->ctx, EVENT_SURVEY, &data);
+
+out_clean:
+ clean_survey_results(survey_results);
+nla_put_failure:
+ return err;
+}
+
const struct wpa_driver_ops wpa_driver_nl80211_ops = {
.name = "nl80211",
@@ -6676,4 +6868,5 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
.add_pmkid = nl80211_add_pmkid,
.remove_pmkid = nl80211_remove_pmkid,
.flush_pmkid = nl80211_flush_pmkid,
+ .get_survey = wpa_driver_nl80211_get_survey,
};
--
1.7.4.15.g7811d
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