2 * hostapd / IEEE 802.11 Management: Beacon and Probe Request/Response
3 * Copyright (c) 2002-2004, Instant802 Networks, Inc.
4 * Copyright (c) 2005-2006, Devicescape Software, Inc.
5 * Copyright (c) 2008-2009, Jouni Malinen <j@w1.fi>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * Alternatively, this software may be distributed under the terms of BSD
14 * See README and COPYING for more details.
17 #include "utils/includes.h"
19 #ifndef CONFIG_NATIVE_WINDOWS
21 #include "utils/common.h"
22 #include "common/ieee802_11_defs.h"
23 #include "common/ieee802_11_common.h"
24 #include "drivers/driver.h"
25 #include "wps/wps_defs.h"
28 #include "ieee802_11.h"
31 #include "ap_config.h"
33 #include "p2p_hostapd.h"
34 #include "ap_drv_ops.h"
38 static u8
ieee802_11_erp_info(struct hostapd_data
*hapd
)
42 if (hapd
->iface
->current_mode
== NULL
||
43 hapd
->iface
->current_mode
->mode
!= HOSTAPD_MODE_IEEE80211G
)
46 switch (hapd
->iconf
->cts_protection_type
) {
47 case CTS_PROTECTION_FORCE_ENABLED
:
48 erp
|= ERP_INFO_NON_ERP_PRESENT
| ERP_INFO_USE_PROTECTION
;
50 case CTS_PROTECTION_FORCE_DISABLED
:
53 case CTS_PROTECTION_AUTOMATIC
:
54 if (hapd
->iface
->olbc
)
55 erp
|= ERP_INFO_USE_PROTECTION
;
57 case CTS_PROTECTION_AUTOMATIC_NO_OLBC
:
58 if (hapd
->iface
->num_sta_non_erp
> 0) {
59 erp
|= ERP_INFO_NON_ERP_PRESENT
|
60 ERP_INFO_USE_PROTECTION
;
64 if (hapd
->iface
->num_sta_no_short_preamble
> 0 ||
65 hapd
->iconf
->preamble
== LONG_PREAMBLE
)
66 erp
|= ERP_INFO_BARKER_PREAMBLE_MODE
;
72 static u8
* hostapd_eid_ds_params(struct hostapd_data
*hapd
, u8
*eid
)
74 *eid
++ = WLAN_EID_DS_PARAMS
;
76 *eid
++ = hapd
->iconf
->channel
;
81 static u8
* hostapd_eid_erp_info(struct hostapd_data
*hapd
, u8
*eid
)
83 if (hapd
->iface
->current_mode
== NULL
||
84 hapd
->iface
->current_mode
->mode
!= HOSTAPD_MODE_IEEE80211G
)
87 /* Set NonERP_present and use_protection bits if there
88 * are any associated NonERP stations. */
89 /* TODO: use_protection bit can be set to zero even if
90 * there are NonERP stations present. This optimization
91 * might be useful if NonERP stations are "quiet".
92 * See 802.11g/D6 E-1 for recommended practice.
93 * In addition, Non ERP present might be set, if AP detects Non ERP
94 * operation on other APs. */
96 /* Add ERP Information element */
97 *eid
++ = WLAN_EID_ERP_INFO
;
99 *eid
++ = ieee802_11_erp_info(hapd
);
105 static u8
* hostapd_eid_country_add(u8
*pos
, u8
*end
, int chan_spacing
,
106 struct hostapd_channel_data
*start
,
107 struct hostapd_channel_data
*prev
)
112 /* first channel number */
113 *pos
++ = start
->chan
;
114 /* number of channels */
115 *pos
++ = (prev
->chan
- start
->chan
) / chan_spacing
+ 1;
116 /* maximum transmit power level */
117 *pos
++ = start
->max_tx_power
;
123 static u8
* hostapd_eid_country(struct hostapd_data
*hapd
, u8
*eid
,
127 u8
*end
= eid
+ max_len
;
129 struct hostapd_hw_modes
*mode
;
130 struct hostapd_channel_data
*start
, *prev
;
131 int chan_spacing
= 1;
133 if (!hapd
->iconf
->ieee80211d
|| max_len
< 6 ||
134 hapd
->iface
->current_mode
== NULL
)
137 *pos
++ = WLAN_EID_COUNTRY
;
138 pos
++; /* length will be set later */
139 os_memcpy(pos
, hapd
->iconf
->country
, 3); /* e.g., 'US ' */
142 mode
= hapd
->iface
->current_mode
;
143 if (mode
->mode
== HOSTAPD_MODE_IEEE80211A
)
147 for (i
= 0; i
< mode
->num_channels
; i
++) {
148 struct hostapd_channel_data
*chan
= &mode
->channels
[i
];
149 if (chan
->flag
& HOSTAPD_CHAN_DISABLED
)
152 prev
->chan
+ chan_spacing
== chan
->chan
&&
153 start
->max_tx_power
== chan
->max_tx_power
) {
155 continue; /* can use same entry */
159 pos
= hostapd_eid_country_add(pos
, end
, chan_spacing
,
164 /* Start new group */
169 pos
= hostapd_eid_country_add(pos
, end
, chan_spacing
,
173 if ((pos
- eid
) & 1) {
176 *pos
++ = 0; /* pad for 16-bit alignment */
179 eid
[1] = (pos
- eid
) - 2;
185 static u8
* hostapd_eid_wpa(struct hostapd_data
*hapd
, u8
*eid
, size_t len
,
186 struct sta_info
*sta
)
191 ie
= wpa_auth_get_wpa_ie(hapd
->wpa_auth
, &ielen
);
192 if (ie
== NULL
|| ielen
> len
)
195 os_memcpy(eid
, ie
, ielen
);
200 void handle_probe_req(struct hostapd_data
*hapd
,
201 const struct ieee80211_mgmt
*mgmt
, size_t len
)
203 struct ieee80211_mgmt
*resp
;
204 struct ieee802_11_elems elems
;
208 size_t ssid_len
, ie_len
;
209 struct sta_info
*sta
= NULL
;
213 ie
= mgmt
->u
.probe_req
.variable
;
214 ie_len
= len
- (IEEE80211_HDRLEN
+ sizeof(mgmt
->u
.probe_req
));
216 for (i
= 0; hapd
->probereq_cb
&& i
< hapd
->num_probereq_cb
; i
++)
217 if (hapd
->probereq_cb
[i
].cb(hapd
->probereq_cb
[i
].ctx
,
218 mgmt
->sa
, ie
, ie_len
) > 0)
221 if (!hapd
->iconf
->send_probe_response
)
224 if (ieee802_11_parse_elems(ie
, ie_len
, &elems
, 0) == ParseFailed
) {
225 wpa_printf(MSG_DEBUG
, "Could not parse ProbeReq from " MACSTR
,
233 if ((!elems
.ssid
|| !elems
.supp_rates
)) {
234 wpa_printf(MSG_DEBUG
, "STA " MACSTR
" sent probe request "
235 "without SSID or supported rates element",
241 if (hapd
->p2p
&& elems
.wps_ie
) {
243 wps
= ieee802_11_vendor_ie_concat(ie
, ie_len
, WPS_DEV_OUI_WFA
);
244 if (wps
&& !p2p_group_match_dev_type(hapd
->p2p_group
, wps
)) {
245 wpa_printf(MSG_MSGDUMP
, "P2P: Ignore Probe Request "
246 "due to mismatch with Requested Device "
253 #endif /* CONFIG_P2P */
255 if (hapd
->conf
->ignore_broadcast_ssid
&& elems
.ssid_len
== 0) {
256 wpa_printf(MSG_MSGDUMP
, "Probe Request from " MACSTR
" for "
257 "broadcast SSID ignored", MAC2STR(mgmt
->sa
));
261 sta
= ap_get_sta(hapd
, mgmt
->sa
);
264 if ((hapd
->conf
->p2p
& P2P_GROUP_OWNER
) &&
265 elems
.ssid_len
== P2P_WILDCARD_SSID_LEN
&&
266 os_memcmp(elems
.ssid
, P2P_WILDCARD_SSID
,
267 P2P_WILDCARD_SSID_LEN
) == 0) {
268 /* Process P2P Wildcard SSID like Wildcard SSID */
271 #endif /* CONFIG_P2P */
273 if (elems
.ssid_len
== 0 ||
274 (elems
.ssid_len
== hapd
->conf
->ssid
.ssid_len
&&
275 os_memcmp(elems
.ssid
, hapd
->conf
->ssid
.ssid
, elems
.ssid_len
) ==
277 ssid
= hapd
->conf
->ssid
.ssid
;
278 ssid_len
= hapd
->conf
->ssid
.ssid_len
;
280 sta
->ssid_probe
= &hapd
->conf
->ssid
;
284 if (!(mgmt
->da
[0] & 0x01)) {
286 ieee802_11_print_ssid(ssid_txt
, elems
.ssid
,
288 wpa_printf(MSG_MSGDUMP
, "Probe Request from " MACSTR
289 " for foreign SSID '%s' (DA " MACSTR
")",
290 MAC2STR(mgmt
->sa
), ssid_txt
,
296 /* TODO: verify that supp_rates contains at least one matching rate
297 * with AP configuration */
298 #define MAX_PROBERESP_LEN 768
299 buflen
= MAX_PROBERESP_LEN
;
301 if (hapd
->wps_probe_resp_ie
)
302 buflen
+= wpabuf_len(hapd
->wps_probe_resp_ie
);
303 #endif /* CONFIG_WPS */
305 if (hapd
->p2p_probe_resp_ie
)
306 buflen
+= wpabuf_len(hapd
->p2p_probe_resp_ie
);
307 #endif /* CONFIG_P2P */
308 resp
= os_zalloc(buflen
);
311 epos
= ((u8
*) resp
) + MAX_PROBERESP_LEN
;
313 resp
->frame_control
= IEEE80211_FC(WLAN_FC_TYPE_MGMT
,
314 WLAN_FC_STYPE_PROBE_RESP
);
315 os_memcpy(resp
->da
, mgmt
->sa
, ETH_ALEN
);
316 os_memcpy(resp
->sa
, hapd
->own_addr
, ETH_ALEN
);
318 os_memcpy(resp
->bssid
, hapd
->own_addr
, ETH_ALEN
);
319 resp
->u
.probe_resp
.beacon_int
=
320 host_to_le16(hapd
->iconf
->beacon_int
);
322 /* hardware or low-level driver will setup seq_ctrl and timestamp */
323 resp
->u
.probe_resp
.capab_info
=
324 host_to_le16(hostapd_own_capab_info(hapd
, sta
, 1));
326 pos
= resp
->u
.probe_resp
.variable
;
327 *pos
++ = WLAN_EID_SSID
;
329 os_memcpy(pos
, ssid
, ssid_len
);
332 /* Supported rates */
333 pos
= hostapd_eid_supp_rates(hapd
, pos
);
336 pos
= hostapd_eid_ds_params(hapd
, pos
);
338 pos
= hostapd_eid_country(hapd
, pos
, epos
- pos
);
340 /* ERP Information element */
341 pos
= hostapd_eid_erp_info(hapd
, pos
);
343 /* Extended supported rates */
344 pos
= hostapd_eid_ext_supp_rates(hapd
, pos
);
347 pos
= hostapd_eid_wpa(hapd
, pos
, epos
- pos
, sta
);
349 #ifdef CONFIG_IEEE80211N
350 pos
= hostapd_eid_ht_capabilities(hapd
, pos
);
351 pos
= hostapd_eid_ht_operation(hapd
, pos
);
352 #endif /* CONFIG_IEEE80211N */
354 /* Wi-Fi Alliance WMM */
355 pos
= hostapd_eid_wmm(hapd
, pos
);
358 if (hapd
->conf
->wps_state
&& hapd
->wps_probe_resp_ie
) {
359 os_memcpy(pos
, wpabuf_head(hapd
->wps_probe_resp_ie
),
360 wpabuf_len(hapd
->wps_probe_resp_ie
));
361 pos
+= wpabuf_len(hapd
->wps_probe_resp_ie
);
363 #endif /* CONFIG_WPS */
366 if ((hapd
->conf
->p2p
& P2P_ENABLED
) && elems
.p2p
&&
367 hapd
->p2p_probe_resp_ie
) {
368 os_memcpy(pos
, wpabuf_head(hapd
->p2p_probe_resp_ie
),
369 wpabuf_len(hapd
->p2p_probe_resp_ie
));
370 pos
+= wpabuf_len(hapd
->p2p_probe_resp_ie
);
372 #endif /* CONFIG_P2P */
373 #ifdef CONFIG_P2P_MANAGER
374 if ((hapd
->conf
->p2p
& (P2P_MANAGE
| P2P_ENABLED
| P2P_GROUP_OWNER
)) ==
376 pos
= hostapd_eid_p2p_manage(hapd
, pos
);
377 #endif /* CONFIG_P2P_MANAGER */
379 if (hostapd_drv_send_mlme(hapd
, resp
, pos
- (u8
*) resp
) < 0)
380 perror("handle_probe_req: send");
384 wpa_printf(MSG_EXCESSIVE
, "STA " MACSTR
" sent probe request for %s "
385 "SSID", MAC2STR(mgmt
->sa
),
386 elems
.ssid_len
== 0 ? "broadcast" : "our");
390 void ieee802_11_set_beacon(struct hostapd_data
*hapd
)
392 struct ieee80211_mgmt
*head
;
393 u8
*pos
, *tail
, *tailpos
;
395 size_t head_len
, tail_len
;
398 if ((hapd
->conf
->p2p
& (P2P_ENABLED
| P2P_GROUP_OWNER
)) == P2P_ENABLED
)
400 #endif /* CONFIG_P2P */
402 #define BEACON_HEAD_BUF_SIZE 256
403 #define BEACON_TAIL_BUF_SIZE 512
404 head
= os_zalloc(BEACON_HEAD_BUF_SIZE
);
405 tail_len
= BEACON_TAIL_BUF_SIZE
;
407 if (hapd
->conf
->wps_state
&& hapd
->wps_beacon_ie
)
408 tail_len
+= wpabuf_len(hapd
->wps_beacon_ie
);
409 #endif /* CONFIG_WPS */
411 if (hapd
->p2p_beacon_ie
)
412 tail_len
+= wpabuf_len(hapd
->p2p_beacon_ie
);
413 #endif /* CONFIG_P2P */
414 tailpos
= tail
= os_malloc(tail_len
);
415 if (head
== NULL
|| tail
== NULL
) {
416 wpa_printf(MSG_ERROR
, "Failed to set beacon data");
422 head
->frame_control
= IEEE80211_FC(WLAN_FC_TYPE_MGMT
,
423 WLAN_FC_STYPE_BEACON
);
424 head
->duration
= host_to_le16(0);
425 os_memset(head
->da
, 0xff, ETH_ALEN
);
427 os_memcpy(head
->sa
, hapd
->own_addr
, ETH_ALEN
);
428 os_memcpy(head
->bssid
, hapd
->own_addr
, ETH_ALEN
);
429 head
->u
.beacon
.beacon_int
=
430 host_to_le16(hapd
->iconf
->beacon_int
);
432 /* hardware or low-level driver will setup seq_ctrl and timestamp */
433 capab_info
= hostapd_own_capab_info(hapd
, NULL
, 0);
434 head
->u
.beacon
.capab_info
= host_to_le16(capab_info
);
435 pos
= &head
->u
.beacon
.variable
[0];
438 *pos
++ = WLAN_EID_SSID
;
439 if (hapd
->conf
->ignore_broadcast_ssid
== 2) {
440 /* clear the data, but keep the correct length of the SSID */
441 *pos
++ = hapd
->conf
->ssid
.ssid_len
;
442 os_memset(pos
, 0, hapd
->conf
->ssid
.ssid_len
);
443 pos
+= hapd
->conf
->ssid
.ssid_len
;
444 } else if (hapd
->conf
->ignore_broadcast_ssid
) {
445 *pos
++ = 0; /* empty SSID */
447 *pos
++ = hapd
->conf
->ssid
.ssid_len
;
448 os_memcpy(pos
, hapd
->conf
->ssid
.ssid
,
449 hapd
->conf
->ssid
.ssid_len
);
450 pos
+= hapd
->conf
->ssid
.ssid_len
;
453 /* Supported rates */
454 pos
= hostapd_eid_supp_rates(hapd
, pos
);
457 pos
= hostapd_eid_ds_params(hapd
, pos
);
459 head_len
= pos
- (u8
*) head
;
461 tailpos
= hostapd_eid_country(hapd
, tailpos
,
462 tail
+ BEACON_TAIL_BUF_SIZE
- tailpos
);
464 /* ERP Information element */
465 tailpos
= hostapd_eid_erp_info(hapd
, tailpos
);
467 /* Extended supported rates */
468 tailpos
= hostapd_eid_ext_supp_rates(hapd
, tailpos
);
471 tailpos
= hostapd_eid_wpa(hapd
, tailpos
, tail
+ BEACON_TAIL_BUF_SIZE
-
474 #ifdef CONFIG_IEEE80211N
475 tailpos
= hostapd_eid_ht_capabilities(hapd
, tailpos
);
476 tailpos
= hostapd_eid_ht_operation(hapd
, tailpos
);
477 #endif /* CONFIG_IEEE80211N */
479 /* Wi-Fi Alliance WMM */
480 tailpos
= hostapd_eid_wmm(hapd
, tailpos
);
483 if (hapd
->conf
->wps_state
&& hapd
->wps_beacon_ie
) {
484 os_memcpy(tailpos
, wpabuf_head(hapd
->wps_beacon_ie
),
485 wpabuf_len(hapd
->wps_beacon_ie
));
486 tailpos
+= wpabuf_len(hapd
->wps_beacon_ie
);
488 #endif /* CONFIG_WPS */
491 if ((hapd
->conf
->p2p
& P2P_ENABLED
) && hapd
->p2p_beacon_ie
) {
492 os_memcpy(tailpos
, wpabuf_head(hapd
->p2p_beacon_ie
),
493 wpabuf_len(hapd
->p2p_beacon_ie
));
494 tailpos
+= wpabuf_len(hapd
->p2p_beacon_ie
);
496 #endif /* CONFIG_P2P */
497 #ifdef CONFIG_P2P_MANAGER
498 if ((hapd
->conf
->p2p
& (P2P_MANAGE
| P2P_ENABLED
| P2P_GROUP_OWNER
)) ==
500 tailpos
= hostapd_eid_p2p_manage(hapd
, tailpos
);
501 #endif /* CONFIG_P2P_MANAGER */
503 tail_len
= tailpos
> tail
? tailpos
- tail
: 0;
505 if (hostapd_drv_set_beacon(hapd
, (u8
*) head
, head_len
,
506 tail
, tail_len
, hapd
->conf
->dtim_period
,
507 hapd
->iconf
->beacon_int
))
508 wpa_printf(MSG_ERROR
, "Failed to set beacon head/tail or DTIM "
516 #endif /* CONFIG_P2P */
517 hostapd_set_bss_params(hapd
, !!(ieee802_11_erp_info(hapd
) &
518 ERP_INFO_USE_PROTECTION
));
522 void ieee802_11_set_beacons(struct hostapd_iface
*iface
)
525 for (i
= 0; i
< iface
->num_bss
; i
++)
526 ieee802_11_set_beacon(iface
->bss
[i
]);
529 #endif /* CONFIG_NATIVE_WINDOWS */