hostapd: Add mechanism to track unconnected stations

[mech_eap.git] / src / ap / beacon.c

diff --git a/src/ap/beacon.c b/src/ap/beacon.c
index 98d6832..46fff82 100644 (file)
--- a/src/ap/beacon.c
+++ b/src/ap/beacon.c
@@ -552,6 +552,76 @@ static enum ssid_match_result ssid_match(struct hostapd_data *hapd,
 }
 
 
+void sta_track_expire(struct hostapd_iface *iface, int force)
+{
+       struct os_reltime now;
+       struct hostapd_sta_info *info;
+
+       if (!iface->num_sta_seen)
+               return;
+
+       os_get_reltime(&now);
+       while ((info = dl_list_first(&iface->sta_seen, struct hostapd_sta_info,
+                                    list))) {
+               if (!force &&
+                   !os_reltime_expired(&now, &info->last_seen,
+                                       iface->conf->track_sta_max_age))
+                       break;
+               force = 0;
+
+               wpa_printf(MSG_MSGDUMP, "%s: Expire STA tracking entry for "
+                          MACSTR, iface->bss[0]->conf->iface,
+                          MAC2STR(info->addr));
+               dl_list_del(&info->list);
+               iface->num_sta_seen--;
+               os_free(info);
+       }
+}
+
+
+static struct hostapd_sta_info * sta_track_get(struct hostapd_iface *iface,
+                                              const u8 *addr)
+{
+       struct hostapd_sta_info *info;
+
+       dl_list_for_each(info, &iface->sta_seen, struct hostapd_sta_info, list)
+               if (os_memcmp(addr, info->addr, ETH_ALEN) == 0)
+                       return info;
+
+       return NULL;
+}
+
+
+static void sta_track_add(struct hostapd_iface *iface, const u8 *addr)
+{
+       struct hostapd_sta_info *info;
+
+       info = sta_track_get(iface, addr);
+       if (info) {
+               /* Move the most recent entry to the end of the list */
+               dl_list_del(&info->list);
+               dl_list_add_tail(&iface->sta_seen, &info->list);
+               os_get_reltime(&info->last_seen);
+               return;
+       }
+
+       /* Add a new entry */
+       info = os_zalloc(sizeof(*info));
+       os_memcpy(info->addr, addr, ETH_ALEN);
+       os_get_reltime(&info->last_seen);
+
+       if (iface->num_sta_seen >= iface->conf->track_sta_max_num) {
+               /* Expire oldest entry to make room for a new one */
+               sta_track_expire(iface, 1);
+       }
+
+       wpa_printf(MSG_MSGDUMP, "%s: Add STA tracking entry for "
+                  MACSTR, iface->bss[0]->conf->iface, MAC2STR(addr));
+       dl_list_add_tail(&iface->sta_seen, &info->list);
+       iface->num_sta_seen++;
+}
+
+
 void handle_probe_req(struct hostapd_data *hapd,
                      const struct ieee80211_mgmt *mgmt, size_t len,
                      int ssi_signal)
@@ -567,6 +637,8 @@ void handle_probe_req(struct hostapd_data *hapd,
        ie = mgmt->u.probe_req.variable;
        if (len < IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req))
                return;
+       if (hapd->iconf->track_sta_max_num)
+               sta_track_add(hapd->iface, mgmt->sa);
        ie_len = len - (IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req));
 
        for (i = 0; hapd->probereq_cb && i < hapd->num_probereq_cb; i++)