[RFC] hostapd: add Automatic Channel Selection (ACS) support
Luis R. Rodriguez
lrodriguez
Tue Jun 21 17:32:20 PDT 2011
This adds Automatic Channel Selection (ACS) support to hostapd
using the Survery based ACS algorithm [1].
[1] http://wireless.kernel.org/en/users/Documentation/acs#Survey_based_algorithm
Signed-off-by: Luis R. Rodriguez <lrodriguez at atheros.com>
---
This is an all in one patch which I intend on splitting up later but
for now I'd like to review / testing. The patch is a bit crude as
I have just finished it and have not gone back to cleanup the
documentation and style everywhere but should be enough for
first review.
hostapd/Makefile | 5 +
hostapd/defconfig | 3 +
src/ap/ap_drv_ops.h | 27 ++++++
src/ap/drv_callbacks.c | 152 ++++++++++++++++++++++++++++++++-
src/ap/hostapd.c | 2 +
src/ap/hostapd.h | 14 +++
src/ap/hw_features.c | 182 +++++++++++++++++++++++++--------------
src/drivers/driver.h | 97 +++++++++++++++++++++-
src/drivers/driver_nl80211.c | 195 ++++++++++++++++++++++++++++++++++++++++++
wpa_supplicant/events.c | 2 +
10 files changed, 611 insertions(+), 68 deletions(-)
diff --git a/hostapd/Makefile b/hostapd/Makefile
index d05975b..5ff51be 100644
--- a/hostapd/Makefile
+++ b/hostapd/Makefile
@@ -736,6 +736,11 @@ CFLAGS += -DCONFIG_P2P_MANAGER
OBJS += ../src/ap/p2p_hostapd.o
endif
+ifdef CONFIG_ACS
+CFLAGS += -DCONFIG_ACS
+OBJS += ../src/ap/acs.o
+endif
+
ifdef CONFIG_NO_STDOUT_DEBUG
CFLAGS += -DCONFIG_NO_STDOUT_DEBUG
endif
diff --git a/hostapd/defconfig b/hostapd/defconfig
index 26be2a8..097a696 100644
--- a/hostapd/defconfig
+++ b/hostapd/defconfig
@@ -208,3 +208,6 @@ CONFIG_IPV6=y
# considered for builds that are known to be used on devices that meet the
# requirements described above.
#CONFIG_NO_RANDOM_POOL=y
+
+# TODO:
+#CONFIG_ACS=y
diff --git a/src/ap/ap_drv_ops.h b/src/ap/ap_drv_ops.h
index f6076af..c9ff723 100644
--- a/src/ap/ap_drv_ops.h
+++ b/src/ap/ap_drv_ops.h
@@ -202,4 +202,31 @@ static inline int hostapd_drv_set_authmode(struct hostapd_data *hapd,
return hapd->driver->set_authmode(hapd->drv_priv, auth_algs);
}
+static inline int hostapd_drv_remain_on_channel(struct hostapd_data *hapd,
+ unsigned int freq,
+ unsigned int duration)
+{
+ if (hapd->driver == NULL)
+ return -1;
+ if (!hapd->driver->remain_on_channel)
+ return -1;
+ 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 02b7ecf..6101831 100644
--- a/src/ap/drv_callbacks.c
+++ b/src/ap/drv_callbacks.c
@@ -35,7 +35,7 @@
#include "wps_hostapd.h"
#include "ap_drv_ops.h"
#include "ap_config.h"
-
+#include "acs.h"
int hostapd_notif_assoc(struct hostapd_data *hapd, const u8 *addr,
const u8 *ie, size_t ielen, int reassoc)
@@ -447,6 +447,143 @@ static void hostapd_event_eapol_rx(struct hostapd_data *hapd, const u8 *src,
ieee802_1x_receive(hapd, src, data, data_len);
}
+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_noise(struct hostapd_iface *iface,
+ struct hostapd_channel_data *chan,
+ struct freq_survey *survey)
+{
+ if (!iface->chans_surveyed) {
+ chan->min_noise = survey->noise;
+ iface->lowest_noise = survey->noise;
+ } else {
+ if (!chan->survey_count)
+ chan->min_noise = survey->noise;
+ else if (survey->noise < chan->min_noise)
+ chan->min_noise = survey->noise;
+ if (survey->noise < iface->lowest_noise)
+ iface->lowest_noise = survey->noise;
+ }
+}
+
+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_noise(iface, chan, survey);
+
+ chan->survey_count++;
+ iface->chans_surveyed++;
+ }
+
+ return;
+fail:
+ /* XXX: move chan clean thingy here from acs.c */
+ iface->chans_surveyed = 0;
+}
+
+static int hostapd_roc_channel_check(struct hostapd_iface *iface)
+{
+ struct hostapd_channel_data *chan = NULL, *offchan;
+ unsigned int i;
+ int found = 0;
+
+ offchan = &iface->current_mode->channels[iface->off_channel_freq_idx];
+
+ for (i = 0; i < iface->current_mode->num_channels; i++) {
+ chan = &iface->current_mode->channels[i];
+ if (offchan != chan)
+ continue;
+ found = 1;
+ break;
+ }
+
+ if (!found || !chan) {
+ wpa_printf(MSG_ERROR, "ACS: channel requested to go offchannel "
+ "on freq %d MHz disappeared",
+ chan->freq);
+ goto fail;
+ }
+
+ if (chan->flag & HOSTAPD_CHAN_DISABLED) {
+ wpa_printf(MSG_ERROR, "ACS: channel requested to go offchannel "
+ "on freq %d MHz became disabled",
+ chan->freq);
+ goto fail;
+ }
+
+
+ return 0;
+fail:
+ return -1;
+}
+
+static void hostapd_event_roc(struct hostapd_data *hapd,
+ unsigned int freq,
+ unsigned int duration)
+{
+ struct hostapd_iface *iface = hapd->iface;
+ int err;
+
+ err = hostapd_roc_channel_check(iface);
+ if (err)
+ goto fail;
+
+ return;
+fail:
+ acs_fail(iface);
+}
+
+static void hostapd_event_roc_cancel(struct hostapd_data *hapd,
+ unsigned int freq,
+ unsigned int duration)
+{
+ struct hostapd_iface *iface = hapd->iface;
+ int err;
+
+ err = hostapd_roc_channel_check(iface);
+ if (err)
+ goto fail;
+
+ acs_roc_next(iface, freq, duration);
+
+ return;
+fail:
+ acs_fail(iface);
+}
void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
union wpa_event_data *data)
@@ -530,6 +667,19 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
break;
hostapd_event_sta_low_ack(hapd, data->low_ack.addr);
break;
+ case EVENT_SURVEY:
+ hostapd_event_get_survey(hapd, &data->survey_results);
+ break;
+ case EVENT_REMAIN_ON_CHANNEL:
+ hostapd_event_roc(hapd,
+ data->remain_on_channel.freq,
+ data->remain_on_channel.duration);
+ break;
+ case EVENT_CANCEL_REMAIN_ON_CHANNEL:
+ hostapd_event_roc_cancel(hapd,
+ data->remain_on_channel.freq,
+ data->remain_on_channel.duration);
+ break;
default:
wpa_printf(MSG_DEBUG, "Unknown event %d", event);
break;
diff --git a/src/ap/hostapd.c b/src/ap/hostapd.c
index d8af571..79f9b66 100644
--- a/src/ap/hostapd.c
+++ b/src/ap/hostapd.c
@@ -700,6 +700,8 @@ static int setup_interface(struct hostapd_iface *iface)
"channel. (%d)", ret);
return -1;
}
+ if (ret == 1)
+ return 0;
ret = hostapd_check_ht_capab(iface);
if (ret < 0)
return -1;
diff --git a/src/ap/hostapd.h b/src/ap/hostapd.h
index d4501a1..3e12093 100644
--- a/src/ap/hostapd.h
+++ b/src/ap/hostapd.h
@@ -221,6 +221,20 @@ struct hostapd_iface {
int olbc_ht;
u16 ht_op_mode;
+
+ /* Offchannel operation helpers */
+ unsigned int off_channel_freq_idx;
+ unsigned int chans_surveyed;
+
+ /* surveying helpers */
+ s8 lowest_noise;
+
+#ifdef CONFIG_ACS
+ /* ACS helpers */
+ unsigned int acs_num_completed_surveys;
+ unsigned int acs_num_req_surveys;
+#endif
+
void (*scan_cb)(struct hostapd_iface *iface);
int (*ctrl_iface_init)(struct hostapd_data *hapd);
diff --git a/src/ap/hw_features.c b/src/ap/hw_features.c
index 86f6811..852c995 100644
--- a/src/ap/hw_features.c
+++ b/src/ap/hw_features.c
@@ -25,6 +25,7 @@
#include "ap_config.h"
#include "ap_drv_ops.h"
#include "hw_features.h"
+#include "acs.h"
void hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
@@ -599,6 +600,114 @@ int hostapd_check_ht_capab(struct hostapd_iface *iface)
return 0;
}
+static int hostapd_is_usable_chan(struct hostapd_iface *iface,
+ int channel,
+ int primary)
+{
+ 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->chan == channel) {
+ if (chan->flag & HOSTAPD_CHAN_DISABLED) {
+ wpa_printf(MSG_ERROR,
+ "%schannel [%i] (%i) is disabled for "
+ "use in AP mode, flags: 0x%x",
+ primary ? "" : "Configured HT40 secondary ",
+ i, chan->chan, chan->flag);
+ } else {
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int hostapd_is_usable_chans(struct hostapd_iface *iface)
+{
+ if (!hostapd_is_usable_chan(iface, iface->conf->channel, 1))
+ return 0;
+
+ if (!iface->conf->secondary_channel)
+ return 1;
+
+ if (!hostapd_is_usable_chan(iface, iface->conf->secondary_channel, 0))
+ return 0;
+
+ return 1;
+}
+
+static int hostapd_check_chans(struct hostapd_iface *iface)
+{
+ if (iface->conf->channel) {
+ if (hostapd_is_usable_chans(iface))
+ return 1;
+ else
+ return 0;
+ }
+
+ /*
+ * We'd reach here if the ACS cb failed to get us a proper channel
+ * somehow
+ */
+ if (iface->chans_surveyed) {
+ wpa_printf(MSG_ERROR, "ACS: no usable channels found");
+ return 0;
+ }
+
+ if (!(iface->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX)) {
+ wpa_printf(MSG_ERROR, "ACS: offchannel TX support required");
+ return 0;
+ }
+
+ wpa_printf(MSG_ERROR, "ACS: automatic channel selection started...");
+
+ acs_init(iface);
+
+ return 2;
+}
+
+static void hostapd_notify_bad_chans(struct hostapd_iface *iface)
+{
+ iface->current_mode = NULL;
+
+ hostapd_logger(iface->bss[0], NULL,
+ HOSTAPD_MODULE_IEEE80211,
+ HOSTAPD_LEVEL_WARNING,
+ "Configured channel (%d) not found from the "
+ "channel list of current mode (%d) %s",
+ iface->conf->channel,
+ iface->current_mode->mode,
+ hostapd_hw_mode_txt(iface->current_mode->mode));
+ hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
+ HOSTAPD_LEVEL_WARNING,
+ "Hardware does not support configured channel");
+}
+
+int hostapd_acs_completed(struct hostapd_iface *iface)
+{
+ int ret;
+
+ if (!hostapd_check_chans(iface)) {
+ hostapd_notify_bad_chans(iface);
+ wpa_printf(MSG_ERROR, "ACS picked unusable channels\n");
+ return -1;
+ }
+
+ ret = hostapd_check_ht_capab(iface);
+ if (ret < 0)
+ return -1;
+ if (ret == 1) {
+ wpa_printf(MSG_DEBUG, "Interface initialization will "
+ "be completed in a callback");
+ return 0;
+ }
+
+ return hostapd_setup_interface_complete(iface, 0);
+}
+
/**
* hostapd_select_hw_mode - Select the hardware mode
@@ -610,7 +719,7 @@ int hostapd_check_ht_capab(struct hostapd_iface *iface)
*/
int hostapd_select_hw_mode(struct hostapd_iface *iface)
{
- int i, j, ok;
+ int i, ok = 0;
if (iface->num_hw_features < 1)
return -1;
@@ -634,74 +743,15 @@ int hostapd_select_hw_mode(struct hostapd_iface *iface)
return -2;
}
- ok = 0;
- for (j = 0; j < iface->current_mode->num_channels; j++) {
- struct hostapd_channel_data *chan =
- &iface->current_mode->channels[j];
- if (chan->chan == iface->conf->channel) {
- if (chan->flag & HOSTAPD_CHAN_DISABLED) {
- wpa_printf(MSG_ERROR,
- "channel [%i] (%i) is disabled for "
- "use in AP mode, flags: 0x%x",
- j, chan->chan, chan->flag);
- } else {
- ok = 1;
- break;
- }
- }
- }
- if (ok && iface->conf->secondary_channel) {
- int sec_ok = 0;
- int sec_chan = iface->conf->channel +
- iface->conf->secondary_channel * 4;
- for (j = 0; j < iface->current_mode->num_channels; j++) {
- struct hostapd_channel_data *chan =
- &iface->current_mode->channels[j];
- if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
- (chan->chan == sec_chan)) {
- sec_ok = 1;
- break;
- }
- }
- if (!sec_ok) {
- hostapd_logger(iface->bss[0], NULL,
- HOSTAPD_MODULE_IEEE80211,
- HOSTAPD_LEVEL_WARNING,
- "Configured HT40 secondary channel "
- "(%d) not found from the channel list "
- "of current mode (%d) %s",
- sec_chan, iface->current_mode->mode,
- hostapd_hw_mode_txt(
- iface->current_mode->mode));
- ok = 0;
- }
- }
- if (iface->conf->channel == 0) {
- /* TODO: could request a scan of neighboring BSSes and select
- * the channel automatically */
- wpa_printf(MSG_ERROR, "Channel not configured "
- "(hw_mode/channel in hostapd.conf)");
- return -3;
- }
- if (ok == 0 && iface->conf->channel != 0) {
- hostapd_logger(iface->bss[0], NULL,
- HOSTAPD_MODULE_IEEE80211,
- HOSTAPD_LEVEL_WARNING,
- "Configured channel (%d) not found from the "
- "channel list of current mode (%d) %s",
- iface->conf->channel,
- iface->current_mode->mode,
- hostapd_hw_mode_txt(iface->current_mode->mode));
- iface->current_mode = NULL;
- }
-
- if (iface->current_mode == NULL) {
- hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
- HOSTAPD_LEVEL_WARNING,
- "Hardware does not support configured channel");
+ ok = hostapd_check_chans(iface);
+ if (!ok) {
+ hostapd_notify_bad_chans(iface);
return -4;
}
+ if (ok == 2) /* ACS will run and later complete */
+ return 1;
+
return 0;
}
diff --git a/src/drivers/driver.h b/src/drivers/driver.h
index 513580a..76af046 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 +59,29 @@ 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_noise - minimum observed noise, in dBm, based on all surveyed channel data
+ */
+ s8 min_noise;
+
+#ifdef CONFIG_ACS
+
+ /*
+ * interference_factor - see http://wireless.kernel.org/en/users/Documentation/acs
+ */
+ long double survey_interference_factor;
+#endif
};
/**
@@ -2253,6 +2277,30 @@ 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
+ * - 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_noise of the channel is updated for
+ * each survey.
+ */
+ int (*get_survey)(void *priv, unsigned int freq);
};
@@ -2655,11 +2703,47 @@ 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
+ * @noise: channel noise 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 noise;
+ 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
*/
union wpa_event_data {
@@ -3187,6 +3271,17 @@ 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 9fa253e..05bd8cd 100644
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -171,6 +171,8 @@ struct wpa_driver_nl80211_data {
struct i802_bss first_bss;
+ unsigned int survey_freq_filter;
+
#ifdef HOSTAPD
int eapol_sock; /* socket for EAPOL frames */
@@ -6554,6 +6556,198 @@ static const char * nl80211_get_radio_name(void *priv)
return drv->phyname;
}
+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->noise = (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->noise,
+ 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",
@@ -6624,4 +6818,5 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
.set_intra_bss = nl80211_set_intra_bss,
.set_param = nl80211_set_param,
.get_radio_name = nl80211_get_radio_name,
+ .get_survey = wpa_driver_nl80211_get_survey,
};
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index e58abdc..5120046 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -2037,11 +2037,13 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
break;
#ifdef CONFIG_P2P
case EVENT_REMAIN_ON_CHANNEL:
+ /* TODO - ACS call (if acs active) - or p2p if not */
wpas_p2p_remain_on_channel_cb(
wpa_s, data->remain_on_channel.freq,
data->remain_on_channel.duration);
break;
case EVENT_CANCEL_REMAIN_ON_CHANNEL:
+ /* TODO - ACS call (if acs active) - or p2p if not */
wpas_p2p_cancel_remain_on_channel_cb(
wpa_s, data->remain_on_channel.freq);
break;
--
1.7.4.15.g7811d
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