void handle_probe_req(struct hostapd_data *hapd,
const struct ieee80211_mgmt *mgmt, size_t len,
int ssi_signal)
{
u8 *resp;
struct ieee802_11_elems elems;
const u8 *ie;
size_t ie_len;
size_t i, resp_len;
int noack;
enum ssid_match_result res;
int ret;
u16 csa_offs[2];
size_t csa_offs_len;
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++)
if (hapd->probereq_cb[i].cb(hapd->probereq_cb[i].ctx,
mgmt->sa, mgmt->da, mgmt->bssid,
ie, ie_len, ssi_signal) > 0)
return;
if (!hapd->iconf->send_probe_response)
return;
if (ieee802_11_parse_elems(ie, ie_len, &elems, 0) == ParseFailed) {
wpa_printf(MSG_DEBUG, "Could not parse ProbeReq from " MACSTR,
MAC2STR(mgmt->sa));
return;
}
if ((!elems.ssid || !elems.supp_rates)) {
wpa_printf(MSG_DEBUG, "STA " MACSTR " sent probe request "
"without SSID or supported rates element",
MAC2STR(mgmt->sa));
return;
}
/*
* No need to reply if the Probe Request frame was sent on an adjacent
* channel. IEEE Std 802.11-2012 describes this as a requirement for an
* AP with dot11RadioMeasurementActivated set to true, but strictly
* speaking does not allow such ignoring of Probe Request frames if
* dot11RadioMeasurementActivated is false. Anyway, this can help reduce
* number of unnecessary Probe Response frames for cases where the STA
* is less likely to see them (Probe Request frame sent on a
* neighboring, but partially overlapping, channel).
*/
if (elems.ds_params &&
hapd->iface->current_mode &&
(hapd->iface->current_mode->mode == HOSTAPD_MODE_IEEE80211G ||
hapd->iface->current_mode->mode == HOSTAPD_MODE_IEEE80211B) &&
hapd->iconf->channel != elems.ds_params[0]) {
wpa_printf(MSG_DEBUG,
"Ignore Probe Request due to DS Params mismatch: chan=%u != ds.chan=%u",
hapd->iconf->channel, elems.ds_params[0]);
return;
}
#ifdef CONFIG_P2P
if (hapd->p2p && hapd->p2p_group && elems.wps_ie) {
struct wpabuf *wps;
wps = ieee802_11_vendor_ie_concat(ie, ie_len, WPS_DEV_OUI_WFA);
if (wps && !p2p_group_match_dev_type(hapd->p2p_group, wps)) {
wpa_printf(MSG_MSGDUMP, "P2P: Ignore Probe Request "
"due to mismatch with Requested Device "
"Type");
wpabuf_free(wps);
return;
}
wpabuf_free(wps);
}
if (hapd->p2p && hapd->p2p_group && elems.p2p) {
struct wpabuf *p2p;
p2p = ieee802_11_vendor_ie_concat(ie, ie_len, P2P_IE_VENDOR_TYPE);
if (p2p && !p2p_group_match_dev_id(hapd->p2p_group, p2p)) {
wpa_printf(MSG_MSGDUMP, "P2P: Ignore Probe Request "
"due to mismatch with Device ID");
wpabuf_free(p2p);
return;
}
wpabuf_free(p2p);
}
#endif /* CONFIG_P2P */
if (hapd->conf->ignore_broadcast_ssid && elems.ssid_len == 0 &&
elems.ssid_list_len == 0) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR " for "
"broadcast SSID ignored", MAC2STR(mgmt->sa));
return;
}
#ifdef CONFIG_P2P
if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
elems.ssid_len == P2P_WILDCARD_SSID_LEN &&
os_memcmp(elems.ssid, P2P_WILDCARD_SSID,
P2P_WILDCARD_SSID_LEN) == 0) {
/* Process P2P Wildcard SSID like Wildcard SSID */
elems.ssid_len = 0;
}
#endif /* CONFIG_P2P */
res = ssid_match(hapd, elems.ssid, elems.ssid_len,
elems.ssid_list, elems.ssid_list_len);
if (res == NO_SSID_MATCH) {
if (!(mgmt->da[0] & 0x01)) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for foreign SSID '%s' (DA " MACSTR ")%s",
MAC2STR(mgmt->sa),
wpa_ssid_txt(elems.ssid, elems.ssid_len),
MAC2STR(mgmt->da),
elems.ssid_list ? " (SSID list)" : "");
}
return;
}
#ifdef CONFIG_INTERWORKING
if (hapd->conf->interworking &&
elems.interworking && elems.interworking_len >= 1) {
u8 ant = elems.interworking[0] & 0x0f;
if (ant != INTERWORKING_ANT_WILDCARD &&
ant != hapd->conf->access_network_type) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for mismatching ANT %u ignored",
MAC2STR(mgmt->sa), ant);
return;
}
}
if (hapd->conf->interworking && elems.interworking &&
(elems.interworking_len == 7 || elems.interworking_len == 9)) {
const u8 *hessid;
if (elems.interworking_len == 7)
hessid = elems.interworking + 1;
else
hessid = elems.interworking + 1 + 2;
if (!is_broadcast_ether_addr(hessid) &&
os_memcmp(hessid, hapd->conf->hessid, ETH_ALEN) != 0) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for mismatching HESSID " MACSTR
" ignored",
MAC2STR(mgmt->sa), MAC2STR(hessid));
return;
}
}
#endif /* CONFIG_INTERWORKING */
#ifdef CONFIG_P2P
if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
supp_rates_11b_only(&elems)) {
/* Indicates support for 11b rates only */
wpa_printf(MSG_EXCESSIVE, "P2P: Ignore Probe Request from "
MACSTR " with only 802.11b rates",
MAC2STR(mgmt->sa));
return;
}
#endif /* CONFIG_P2P */
/* TODO: verify that supp_rates contains at least one matching rate
* with AP configuration */
if (hapd->conf->no_probe_resp_if_seen_on &&
is_multicast_ether_addr(mgmt->da) &&
is_multicast_ether_addr(mgmt->bssid) &&
sta_track_seen_on(hapd->iface, mgmt->sa,
hapd->conf->no_probe_resp_if_seen_on)) {
wpa_printf(MSG_MSGDUMP, "%s: Ignore Probe Request from " MACSTR
" since STA has been seen on %s",
hapd->conf->iface, MAC2STR(mgmt->sa),
hapd->conf->no_probe_resp_if_seen_on);
return;
}
if (hapd->conf->no_probe_resp_if_max_sta &&
is_multicast_ether_addr(mgmt->da) &&
is_multicast_ether_addr(mgmt->bssid) &&
hapd->num_sta >= hapd->conf->max_num_sta &&
!ap_get_sta(hapd, mgmt->sa)) {
wpa_printf(MSG_MSGDUMP, "%s: Ignore Probe Request from " MACSTR
" since no room for additional STA",
hapd->conf->iface, MAC2STR(mgmt->sa));
return;
}
#ifdef CONFIG_TESTING_OPTIONS
if (hapd->iconf->ignore_probe_probability > 0.0 &&
drand48() < hapd->iconf->ignore_probe_probability) {
wpa_printf(MSG_INFO,
"TESTING: ignoring probe request from " MACSTR,
MAC2STR(mgmt->sa));
return;
}
#endif /* CONFIG_TESTING_OPTIONS */
resp = hostapd_gen_probe_resp(hapd, mgmt, elems.p2p != NULL,
&resp_len);
if (resp == NULL)
return;
/*
* If this is a broadcast probe request, apply no ack policy to avoid
* excessive retries.
*/
noack = !!(res == WILDCARD_SSID_MATCH &&
is_broadcast_ether_addr(mgmt->da));
csa_offs_len = 0;
if (hapd->csa_in_progress) {
if (hapd->cs_c_off_proberesp)
csa_offs[csa_offs_len++] =
hapd->cs_c_off_proberesp;
if (hapd->cs_c_off_ecsa_proberesp)
csa_offs[csa_offs_len++] =
hapd->cs_c_off_ecsa_proberesp;
}
ret = hostapd_drv_send_mlme_csa(hapd, resp, resp_len, noack,
csa_offs_len ? csa_offs : NULL,
csa_offs_len);
if (ret < 0)
wpa_printf(MSG_INFO, "handle_probe_req: send failed");
os_free(resp);
wpa_printf(MSG_EXCESSIVE, "STA " MACSTR " sent probe request for %s "
"SSID", MAC2STR(mgmt->sa),
elems.ssid_len == 0 ? "broadcast" : "our");
}
void handle_probe_req(struct hostapd_data *hapd,
const struct ieee80211_mgmt *mgmt, size_t len,
int ssi_signal)
{
u8 *resp;
struct ieee802_11_elems elems;
const u8 *ie;
size_t ie_len;
struct sta_info *sta = NULL;
size_t i, resp_len;
int noack;
enum ssid_match_result res;
int iterate = 0;
ie = mgmt->u.probe_req.variable;
if (len < IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req))
return;
ie_len = len - (IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req));
for (i = 0; hapd->probereq_cb && i < hapd->num_probereq_cb; i++)
if (hapd->probereq_cb[i].cb(hapd->probereq_cb[i].ctx,
mgmt->sa, mgmt->da, mgmt->bssid,
ie, ie_len, ssi_signal) > 0)
return;
if (!hapd->iconf->send_probe_response)
return;
if (ieee802_11_parse_elems(ie, ie_len, &elems, 0) == ParseFailed) {
wpa_printf(MSG_DEBUG, "Could not parse ProbeReq from " MACSTR,
MAC2STR(mgmt->sa));
return;
}
if ((!elems.ssid || !elems.supp_rates)) {
wpa_printf(MSG_DEBUG, "STA " MACSTR " sent probe request "
"without SSID or supported rates element",
MAC2STR(mgmt->sa));
return;
}
#ifdef CONFIG_P2P
if (hapd->p2p && elems.wps_ie) {
struct wpabuf *wps;
wps = ieee802_11_vendor_ie_concat(ie, ie_len, WPS_DEV_OUI_WFA);
if (wps && !p2p_group_match_dev_type(hapd->p2p_group, wps)) {
wpa_printf(MSG_MSGDUMP, "P2P: Ignore Probe Request "
"due to mismatch with Requested Device "
"Type");
wpabuf_free(wps);
return;
}
wpabuf_free(wps);
}
if (hapd->p2p && elems.p2p) {
struct wpabuf *p2p;
p2p = ieee802_11_vendor_ie_concat(ie, ie_len, P2P_IE_VENDOR_TYPE);
if (p2p && !p2p_group_match_dev_id(hapd->p2p_group, p2p)) {
wpa_printf(MSG_MSGDUMP, "P2P: Ignore Probe Request "
"due to mismatch with Device ID");
wpabuf_free(p2p);
return;
}
wpabuf_free(p2p);
}
#endif /* CONFIG_P2P */
if (hapd->conf->ignore_broadcast_ssid && elems.ssid_len == 0 &&
elems.ssid_list_len == 0 && !hapd->iconf->enable_karma) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR " for "
"broadcast SSID ignored", MAC2STR(mgmt->sa));
return;
}
sta = ap_get_sta(hapd, mgmt->sa);
#ifdef CONFIG_P2P
if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
elems.ssid_len == P2P_WILDCARD_SSID_LEN &&
os_memcmp(elems.ssid, P2P_WILDCARD_SSID,
P2P_WILDCARD_SSID_LEN) == 0) {
/* Process P2P Wildcard SSID like Wildcard SSID */
elems.ssid_len = 0;
}
#endif /* CONFIG_P2P */
res = ssid_match(hapd, elems.ssid, elems.ssid_len,
elems.ssid_list, elems.ssid_list_len);
// todo handle ssid_list see ssid_match for code
// todo change emit code below (global flag?)
if (res == EXACT_SSID_MATCH) { //Probed for configured address
if (hapd->iconf->enable_karma) {
wpa_printf(MSG_DEBUG,"MANA - Directed probe request for actual/legitimate SSID '%s' from " MACSTR "",wpa_ssid_txt(elems.ssid, elems.ssid_len),MAC2STR(mgmt->sa));
}
if (sta) {
sta->ssid_probe = &hapd->conf->ssid;
sta->ssid_probe_karma = &hapd->conf->ssid;
}
} else if (res == NO_SSID_MATCH) { //Probed for unseen SSID
wpa_printf(MSG_DEBUG,"MANA - Directed probe request for foreign SSID '%s' from " MACSTR "",wpa_ssid_txt(elems.ssid, elems.ssid_len),MAC2STR(mgmt->sa));
if (hapd->iconf->enable_karma) {
if (sta) {
// Make hostapd think they probed for us, necessary for security policy
sta->ssid_probe = &hapd->conf->ssid;
// Store what was actually probed for
sta->ssid_probe_karma = (struct hostapd_ssid*)os_malloc(sizeof(struct hostapd_ssid));
os_memcpy(sta->ssid_probe_karma,&hapd->conf->ssid,sizeof(hapd->conf->ssid));
os_memcpy(sta->ssid_probe_karma->ssid, elems.ssid, elems.ssid_len);
sta->ssid_probe_karma->ssid[elems.ssid_len] = '\0';
sta->ssid_probe_karma->ssid_len = elems.ssid_len;
}
// Check if the SSID probed for is in the hash for this STA
struct karma_ssid *d = NULL;
HASH_FIND_STR(karma_data, wpa_ssid_txt(elems.ssid, elems.ssid_len), d);
if (d == NULL) {
wpa_printf(MSG_MSGDUMP, "MANA - Adding SSID %s(%d) for STA " MACSTR " to the hash.", wpa_ssid_txt(elems.ssid, elems.ssid_len), elems.ssid_len, MAC2STR(mgmt->sa));
d = (struct karma_ssid*)os_malloc(sizeof(struct karma_ssid));
os_memcpy(d->ssid_txt, wpa_ssid_txt(elems.ssid, elems.ssid_len), elems.ssid_len+1);
os_memcpy(d->ssid, elems.ssid, elems.ssid_len);
d->ssid_len = elems.ssid_len;
os_memcpy(d->sta_addr, mgmt->sa, ETH_ALEN);
HASH_ADD_STR(karma_data, ssid_txt, d);
}
} else { //No SSID Match and no Karma behave as normal
if (!(mgmt->da[0] & 0x01)) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for foreign SSID '%s' (DA " MACSTR ")%s",
MAC2STR(mgmt->sa),
wpa_ssid_txt(elems.ssid, elems.ssid_len),
MAC2STR(mgmt->da),
elems.ssid_list ? " (SSID list)" : "");
}
return;
}
} else { //Probed for wildcard i.e. WILDCARD_SSID_MATCH
if (hapd->iconf->enable_karma) {
wpa_printf(MSG_DEBUG,"MANA - Broadcast probe request from " MACSTR "",MAC2STR(mgmt->sa));
iterate = 1; //iterate through hash emitting multiple probe responses
}
if (sta)
sta->ssid_probe = &hapd->conf->ssid;
}
#ifdef CONFIG_INTERWORKING
if (hapd->conf->interworking &&
elems.interworking && elems.interworking_len >= 1) {
u8 ant = elems.interworking[0] & 0x0f;
if (ant != INTERWORKING_ANT_WILDCARD &&
ant != hapd->conf->access_network_type) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for mismatching ANT %u ignored",
MAC2STR(mgmt->sa), ant);
return;
}
}
if (hapd->conf->interworking && elems.interworking &&
(elems.interworking_len == 7 || elems.interworking_len == 9)) {
const u8 *hessid;
if (elems.interworking_len == 7)
hessid = elems.interworking + 1;
else
hessid = elems.interworking + 1 + 2;
if (!is_broadcast_ether_addr(hessid) &&
os_memcmp(hessid, hapd->conf->hessid, ETH_ALEN) != 0) {
wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
" for mismatching HESSID " MACSTR
" ignored",
MAC2STR(mgmt->sa), MAC2STR(hessid));
return;
}
}
#endif /* CONFIG_INTERWORKING */
#ifdef CONFIG_P2P
if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
supp_rates_11b_only(&elems)) {
/* Indicates support for 11b rates only */
wpa_printf(MSG_EXCESSIVE, "P2P: Ignore Probe Request from "
MACSTR " with only 802.11b rates",
MAC2STR(mgmt->sa));
return;
}
#endif /* CONFIG_P2P */
/* TODO: verify that supp_rates contains at least one matching rate
* with AP configuration */
#ifdef CONFIG_TESTING_OPTIONS
if (hapd->iconf->ignore_probe_probability > 0.0 &&
drand48() < hapd->iconf->ignore_probe_probability) {
wpa_printf(MSG_INFO,
"TESTING: ignoring probe request from " MACSTR,
MAC2STR(mgmt->sa));
return;
}
#endif /* CONFIG_TESTING_OPTIONS */
resp = hostapd_gen_probe_resp(hapd, sta, elems.ssid, elems.ssid_len,
mgmt, elems.p2p != NULL, &resp_len);
if (resp == NULL)
return;
/*
* If this is a broadcast probe request, apply no ack policy to avoid
* excessive retries.
*/
noack = !!(res == WILDCARD_SSID_MATCH &&
is_broadcast_ether_addr(mgmt->da));
if (hostapd_drv_send_mlme(hapd, resp, resp_len, noack) < 0)
wpa_printf(MSG_INFO, "handle_probe_req: send failed");
os_free(resp);
if (iterate) { // Only iterate through the hash if this is set
struct karma_ssid *k;
for ( k = karma_data; k != NULL; k = (struct karma_ssid*)(k->hh.next))
{
u8 *resp2;
size_t resp2_len;
int flag = 0;
if (hapd->iconf->karma_loud) {
wpa_printf(MSG_INFO, "MANA - Generated LOUD Broadcast response : %s (%zu) for STA " MACSTR, k->ssid_txt, k->ssid_len, MAC2STR(k->sta_addr));
resp2 = hostapd_gen_probe_resp(hapd, sta, k->ssid, k->ssid_len, mgmt, elems.p2p != NULL, &resp2_len);
flag = 1;
} else { //non-loud karma mode
if (os_memcmp(k->sta_addr, mgmt->sa, ETH_ALEN) == 0) {
wpa_printf(MSG_INFO, "MANA - Generated Broadcast response : %s (%zu) for STA " MACSTR, k->ssid_txt, k->ssid_len, MAC2STR(k->sta_addr));
resp2 = hostapd_gen_probe_resp(hapd, sta, k->ssid, k->ssid_len, mgmt, elems.p2p != NULL, &resp2_len);
flag = 1;
}
}
if (flag == 1) {
if (resp2 == NULL) {
wpa_printf(MSG_ERROR, "MANA - Could not generate SSID response for %s (%zu)", k->ssid_txt, k->ssid_len);
} else {
wpa_printf(MSG_MSGDUMP, "MANA - Successfully generated SSID response for %s (len %zu) :)", k->ssid_txt, k->ssid_len);
if (hostapd_drv_send_mlme(hapd, resp2, resp2_len, noack) < 0) {
wpa_printf(MSG_ERROR, "MANA - Failed sending prove response for SSID %s (%zu)", k->ssid_txt, k->ssid_len);
}
os_free(resp2);
}
}
}
}
wpa_printf(MSG_EXCESSIVE, "STA " MACSTR " sent probe request for %s "
"SSID", MAC2STR(mgmt->sa),
elems.ssid_len == 0 ? "broadcast" : "our");
}