nl80211: Suppport multiple CSA counters

Channel switch may be performed using both CSA and eCSA IEs together.
This may happen, for example with a P2P GO on band A with legacy
clients. Extend driver API to support up to 2 CSA counters.

This patch also includes the required implementation for nl80211.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

diff --git a/src/ap/hostapd.c b/src/ap/hostapd.c
index 39ea407..89bfe5b 100644 (file)
--- a/src/ap/hostapd.c
+++ b/src/ap/hostapd.c
@@ -2848,8 +2848,8 @@ static int hostapd_fill_csa_settings(struct hostapd_data *hapd,
                return ret;
        }
 
-       settings->counter_offset_beacon = hapd->cs_c_off_beacon;
-       settings->counter_offset_presp = hapd->cs_c_off_proberesp;
+       settings->counter_offset_beacon[0] = hapd->cs_c_off_beacon;
+       settings->counter_offset_presp[0] = hapd->cs_c_off_proberesp;
 
        return 0;
 }

diff --git a/src/drivers/driver.h b/src/drivers/driver.h
index 830ff80..262dc3f 100644 (file)
--- a/src/drivers/driver.h
+++ b/src/drivers/driver.h
@@ -1306,6 +1306,9 @@ struct wpa_driver_capa {
        unsigned int max_conc_chan_2_4;
        /* Maximum number of concurrent channels on 5 GHz */
        unsigned int max_conc_chan_5_0;
+
+       /* Maximum number of supported CSA counters */
+       u16 max_csa_counters;
 };
 
 
@@ -1556,8 +1559,8 @@ struct csa_settings {
        struct beacon_data beacon_csa;
        struct beacon_data beacon_after;
 
-       u16 counter_offset_beacon;
-       u16 counter_offset_presp;
+       u16 counter_offset_beacon[2];
+       u16 counter_offset_presp[2];
 };
 
 /* TDLS peer capabilities for send_tdls_mgmt() */

diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index b13d18c..f89bc24 100644 (file)
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -7576,6 +7576,8 @@ static int nl80211_switch_channel(void *priv, struct csa_settings *settings)
        struct wpa_driver_nl80211_data *drv = bss->drv;
        struct nlattr *beacon_csa;
        int ret = -ENOBUFS;
+       int csa_off_len = 0;
+       int i;
 
        wpa_printf(MSG_DEBUG, "nl80211: Channel switch request (cs_count=%u block_tx=%u freq=%d width=%d cf1=%d cf2=%d)",
                   settings->cs_count, settings->block_tx,
@@ -7592,20 +7594,56 @@ static int nl80211_switch_channel(void *priv, struct csa_settings *settings)
            (drv->nlmode != NL80211_IFTYPE_P2P_GO))
                return -EOPNOTSUPP;
 
-       /* check settings validity */
-       if (!settings->beacon_csa.tail ||
-           ((settings->beacon_csa.tail_len <=
-             settings->counter_offset_beacon) ||
-            (settings->beacon_csa.tail[settings->counter_offset_beacon] !=
-             settings->cs_count)))
+       /*
+        * Remove empty counters, assuming Probe Response and Beacon frame
+        * counters match. This implementation assumes that there are only two
+        * counters.
+        */
+       if (settings->counter_offset_beacon[0] &&
+           !settings->counter_offset_beacon[1]) {
+               csa_off_len = 1;
+       } else if (settings->counter_offset_beacon[1] &&
+                  !settings->counter_offset_beacon[0]) {
+               csa_off_len = 1;
+               settings->counter_offset_beacon[0] =
+                       settings->counter_offset_beacon[1];
+               settings->counter_offset_presp[0] =
+                       settings->counter_offset_presp[1];
+       } else if (settings->counter_offset_beacon[1] &&
+                  settings->counter_offset_beacon[0]) {
+               csa_off_len = 2;
+       } else {
+               wpa_printf(MSG_ERROR, "nl80211: No CSA counters provided");
                return -EINVAL;
+       }
 
-       if (settings->beacon_csa.probe_resp &&
-           ((settings->beacon_csa.probe_resp_len <=
-             settings->counter_offset_presp) ||
-            (settings->beacon_csa.probe_resp[settings->counter_offset_presp] !=
-             settings->cs_count)))
+       /* Check CSA counters validity */
+       if (drv->capa.max_csa_counters &&
+           csa_off_len > drv->capa.max_csa_counters) {
+               wpa_printf(MSG_ERROR,
+                          "nl80211: Too many CSA counters provided");
                return -EINVAL;
+       }
+
+       if (!settings->beacon_csa.tail)
+               return -EINVAL;
+
+       for (i = 0; i < csa_off_len; i++) {
+               u16 csa_c_off_bcn = settings->counter_offset_beacon[i];
+               u16 csa_c_off_presp = settings->counter_offset_presp[i];
+
+               if ((settings->beacon_csa.tail_len <= csa_c_off_bcn) ||
+                   (settings->beacon_csa.tail[csa_c_off_bcn] !=
+                    settings->cs_count))
+                       return -EINVAL;
+
+               if (settings->beacon_csa.probe_resp &&
+                   ((settings->beacon_csa.probe_resp_len <=
+                     csa_c_off_presp) ||
+                    (settings->beacon_csa.probe_resp[csa_c_off_presp] !=
+                     settings->cs_count)))
+                       return -EINVAL;
+       }
 
        if (!(msg = nl80211_bss_msg(bss, 0, NL80211_CMD_CHANNEL_SWITCH)) ||
            nla_put_u32(msg, NL80211_ATTR_CH_SWITCH_COUNT,
@@ -7629,11 +7667,13 @@ static int nl80211_switch_channel(void *priv, struct csa_settings *settings)
        if (ret)
                goto error;
 
-       if (nla_put_u16(msg, NL80211_ATTR_CSA_C_OFF_BEACON,
-                       settings->counter_offset_beacon) ||
+       if (nla_put(msg, NL80211_ATTR_CSA_C_OFF_BEACON,
+                   csa_off_len * sizeof(u16),
+                   settings->counter_offset_beacon) ||
            (settings->beacon_csa.probe_resp &&
-            nla_put_u16(msg, NL80211_ATTR_CSA_C_OFF_PRESP,
-                        settings->counter_offset_presp)))
+            nla_put(msg, NL80211_ATTR_CSA_C_OFF_PRESP,
+                    csa_off_len * sizeof(u16),
+                    settings->counter_offset_presp)))
                goto fail;
 
        nla_nest_end(msg, beacon_csa);

diff --git a/src/drivers/driver_nl80211_capa.c b/src/drivers/driver_nl80211_capa.c
index 5c82546..59a8efb 100644 (file)
--- a/src/drivers/driver_nl80211_capa.c
+++ b/src/drivers/driver_nl80211_capa.c
@@ -638,6 +638,10 @@ static int wiphy_info_handler(struct nl_msg *msg, void *arg)
                capa->max_stations =
                        nla_get_u32(tb[NL80211_ATTR_MAX_AP_ASSOC_STA]);
 
+       if (tb[NL80211_ATTR_MAX_CSA_COUNTERS])
+               capa->max_csa_counters =
+                       nla_get_u8(tb[NL80211_ATTR_MAX_CSA_COUNTERS]);
+
        return NL_SKIP;
 }
 
@@ -694,8 +698,6 @@ static int wpa_driver_nl80211_get_info(struct wpa_driver_nl80211_data *drv,
        if (!drv->capa.max_remain_on_chan)
                drv->capa.max_remain_on_chan = 5000;
 
-       if (info->channel_switch_supported)
-               drv->capa.flags |= WPA_DRIVER_FLAGS_AP_CSA;
        drv->capa.wmm_ac_supported = info->wmm_ac_supported;
 
        drv->capa.mac_addr_rand_sched_scan_supported =
@@ -703,6 +705,12 @@ static int wpa_driver_nl80211_get_info(struct wpa_driver_nl80211_data *drv,
        drv->capa.mac_addr_rand_scan_supported =
                info->mac_addr_rand_scan_supported;
 
+       if (info->channel_switch_supported) {
+               drv->capa.flags |= WPA_DRIVER_FLAGS_AP_CSA;
+               if (!drv->capa.max_csa_counters)
+                       drv->capa.max_csa_counters = 1;
+       }
+
        return 0;
 }