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"
36 static u8
ieee802_11_erp_info(struct hostapd_data
*hapd
)
40 if (hapd
->iface
->current_mode
== NULL
||
41 hapd
->iface
->current_mode
->mode
!= HOSTAPD_MODE_IEEE80211G
)
44 switch (hapd
->iconf
->cts_protection_type
) {
45 case CTS_PROTECTION_FORCE_ENABLED
:
46 erp
|= ERP_INFO_NON_ERP_PRESENT
| ERP_INFO_USE_PROTECTION
;
48 case CTS_PROTECTION_FORCE_DISABLED
:
51 case CTS_PROTECTION_AUTOMATIC
:
52 if (hapd
->iface
->olbc
)
53 erp
|= ERP_INFO_USE_PROTECTION
;
55 case CTS_PROTECTION_AUTOMATIC_NO_OLBC
:
56 if (hapd
->iface
->num_sta_non_erp
> 0) {
57 erp
|= ERP_INFO_NON_ERP_PRESENT
|
58 ERP_INFO_USE_PROTECTION
;
62 if (hapd
->iface
->num_sta_no_short_preamble
> 0 ||
63 hapd
->iconf
->preamble
== LONG_PREAMBLE
)
64 erp
|= ERP_INFO_BARKER_PREAMBLE_MODE
;
70 static u8
* hostapd_eid_ds_params(struct hostapd_data
*hapd
, u8
*eid
)
72 *eid
++ = WLAN_EID_DS_PARAMS
;
74 *eid
++ = hapd
->iconf
->channel
;
79 static u8
* hostapd_eid_erp_info(struct hostapd_data
*hapd
, u8
*eid
)
81 if (hapd
->iface
->current_mode
== NULL
||
82 hapd
->iface
->current_mode
->mode
!= HOSTAPD_MODE_IEEE80211G
)
85 /* Set NonERP_present and use_protection bits if there
86 * are any associated NonERP stations. */
87 /* TODO: use_protection bit can be set to zero even if
88 * there are NonERP stations present. This optimization
89 * might be useful if NonERP stations are "quiet".
90 * See 802.11g/D6 E-1 for recommended practice.
91 * In addition, Non ERP present might be set, if AP detects Non ERP
92 * operation on other APs. */
94 /* Add ERP Information element */
95 *eid
++ = WLAN_EID_ERP_INFO
;
97 *eid
++ = ieee802_11_erp_info(hapd
);
103 static u8
* hostapd_eid_country_add(u8
*pos
, u8
*end
, int chan_spacing
,
104 struct hostapd_channel_data
*start
,
105 struct hostapd_channel_data
*prev
)
110 /* first channel number */
111 *pos
++ = start
->chan
;
112 /* number of channels */
113 *pos
++ = (prev
->chan
- start
->chan
) / chan_spacing
+ 1;
114 /* maximum transmit power level */
115 *pos
++ = start
->max_tx_power
;
121 static u8
* hostapd_eid_country(struct hostapd_data
*hapd
, u8
*eid
,
125 u8
*end
= eid
+ max_len
;
127 struct hostapd_hw_modes
*mode
;
128 struct hostapd_channel_data
*start
, *prev
;
129 int chan_spacing
= 1;
131 if (!hapd
->iconf
->ieee80211d
|| max_len
< 6 ||
132 hapd
->iface
->current_mode
== NULL
)
135 *pos
++ = WLAN_EID_COUNTRY
;
136 pos
++; /* length will be set later */
137 os_memcpy(pos
, hapd
->iconf
->country
, 3); /* e.g., 'US ' */
140 mode
= hapd
->iface
->current_mode
;
141 if (mode
->mode
== HOSTAPD_MODE_IEEE80211A
)
145 for (i
= 0; i
< mode
->num_channels
; i
++) {
146 struct hostapd_channel_data
*chan
= &mode
->channels
[i
];
147 if (chan
->flag
& HOSTAPD_CHAN_DISABLED
)
150 prev
->chan
+ chan_spacing
== chan
->chan
&&
151 start
->max_tx_power
== chan
->max_tx_power
) {
153 continue; /* can use same entry */
157 pos
= hostapd_eid_country_add(pos
, end
, chan_spacing
,
162 /* Start new group */
167 pos
= hostapd_eid_country_add(pos
, end
, chan_spacing
,
171 if ((pos
- eid
) & 1) {
174 *pos
++ = 0; /* pad for 16-bit alignment */
177 eid
[1] = (pos
- eid
) - 2;
183 static u8
* hostapd_eid_wpa(struct hostapd_data
*hapd
, u8
*eid
, size_t len
,
184 struct sta_info
*sta
)
189 ie
= wpa_auth_get_wpa_ie(hapd
->wpa_auth
, &ielen
);
190 if (ie
== NULL
|| ielen
> len
)
193 os_memcpy(eid
, ie
, ielen
);
198 #ifdef CONFIG_P2P_MANAGER
199 u8
* hostapd_eid_p2p_manage(struct hostapd_data
*hapd
, u8
*eid
)
202 *eid
++ = WLAN_EID_VENDOR_SPECIFIC
;
204 WPA_PUT_BE24(eid
, OUI_WFA
);
206 *eid
++ = P2P_OUI_TYPE
;
208 *eid
++ = P2P_ATTR_MANAGEABILITY
;
209 WPA_PUT_LE16(eid
, 1);
211 bitmap
= BIT(0); /* P2P Device Management */
212 if (hapd
->conf
->p2p
& P2P_ALLOW_CROSS_CONNECTION
)
213 bitmap
|= BIT(1); /* Cross Connection Permitted */
218 #endif /* CONFIG_P2P_MANAGER */
221 void handle_probe_req(struct hostapd_data
*hapd
,
222 const struct ieee80211_mgmt
*mgmt
, size_t len
)
224 struct ieee80211_mgmt
*resp
;
225 struct ieee802_11_elems elems
;
229 size_t ssid_len
, ie_len
;
230 struct sta_info
*sta
= NULL
;
234 ie
= mgmt
->u
.probe_req
.variable
;
235 ie_len
= len
- (IEEE80211_HDRLEN
+ sizeof(mgmt
->u
.probe_req
));
237 for (i
= 0; hapd
->probereq_cb
&& i
< hapd
->num_probereq_cb
; i
++)
238 if (hapd
->probereq_cb
[i
].cb(hapd
->probereq_cb
[i
].ctx
,
239 mgmt
->sa
, ie
, ie_len
) > 0)
242 if (!hapd
->iconf
->send_probe_response
)
245 if (ieee802_11_parse_elems(ie
, ie_len
, &elems
, 0) == ParseFailed
) {
246 wpa_printf(MSG_DEBUG
, "Could not parse ProbeReq from " MACSTR
,
254 if ((!elems
.ssid
|| !elems
.supp_rates
)) {
255 wpa_printf(MSG_DEBUG
, "STA " MACSTR
" sent probe request "
256 "without SSID or supported rates element",
262 if (hapd
->p2p
&& elems
.wps_ie
) {
264 wps
= ieee802_11_vendor_ie_concat(ie
, ie_len
, WPS_DEV_OUI_WFA
);
265 if (wps
&& !p2p_group_match_dev_type(hapd
->p2p_group
, wps
)) {
266 wpa_printf(MSG_MSGDUMP
, "P2P: Ignore Probe Request "
267 "due to mismatch with Requested Device "
274 #endif /* CONFIG_P2P */
276 if (hapd
->conf
->ignore_broadcast_ssid
&& elems
.ssid_len
== 0) {
277 wpa_printf(MSG_MSGDUMP
, "Probe Request from " MACSTR
" for "
278 "broadcast SSID ignored", MAC2STR(mgmt
->sa
));
282 sta
= ap_get_sta(hapd
, mgmt
->sa
);
285 if ((hapd
->conf
->p2p
& P2P_GROUP_OWNER
) &&
286 elems
.ssid_len
== P2P_WILDCARD_SSID_LEN
&&
287 os_memcmp(elems
.ssid
, P2P_WILDCARD_SSID
,
288 P2P_WILDCARD_SSID_LEN
) == 0) {
289 /* Process P2P Wildcard SSID like Wildcard SSID */
292 #endif /* CONFIG_P2P */
294 if (elems
.ssid_len
== 0 ||
295 (elems
.ssid_len
== hapd
->conf
->ssid
.ssid_len
&&
296 os_memcmp(elems
.ssid
, hapd
->conf
->ssid
.ssid
, elems
.ssid_len
) ==
298 ssid
= hapd
->conf
->ssid
.ssid
;
299 ssid_len
= hapd
->conf
->ssid
.ssid_len
;
301 sta
->ssid_probe
= &hapd
->conf
->ssid
;
305 if (!(mgmt
->da
[0] & 0x01)) {
307 ieee802_11_print_ssid(ssid_txt
, elems
.ssid
,
309 wpa_printf(MSG_MSGDUMP
, "Probe Request from " MACSTR
310 " for foreign SSID '%s' (DA " MACSTR
")",
311 MAC2STR(mgmt
->sa
), ssid_txt
,
317 /* TODO: verify that supp_rates contains at least one matching rate
318 * with AP configuration */
319 #define MAX_PROBERESP_LEN 768
320 buflen
= MAX_PROBERESP_LEN
;
322 if (hapd
->wps_probe_resp_ie
)
323 buflen
+= wpabuf_len(hapd
->wps_probe_resp_ie
);
324 #endif /* CONFIG_WPS */
326 if (hapd
->p2p_probe_resp_ie
)
327 buflen
+= wpabuf_len(hapd
->p2p_probe_resp_ie
);
328 #endif /* CONFIG_P2P */
329 resp
= os_zalloc(buflen
);
332 epos
= ((u8
*) resp
) + MAX_PROBERESP_LEN
;
334 resp
->frame_control
= IEEE80211_FC(WLAN_FC_TYPE_MGMT
,
335 WLAN_FC_STYPE_PROBE_RESP
);
336 os_memcpy(resp
->da
, mgmt
->sa
, ETH_ALEN
);
337 os_memcpy(resp
->sa
, hapd
->own_addr
, ETH_ALEN
);
339 os_memcpy(resp
->bssid
, hapd
->own_addr
, ETH_ALEN
);
340 resp
->u
.probe_resp
.beacon_int
=
341 host_to_le16(hapd
->iconf
->beacon_int
);
343 /* hardware or low-level driver will setup seq_ctrl and timestamp */
344 resp
->u
.probe_resp
.capab_info
=
345 host_to_le16(hostapd_own_capab_info(hapd
, sta
, 1));
347 pos
= resp
->u
.probe_resp
.variable
;
348 *pos
++ = WLAN_EID_SSID
;
350 os_memcpy(pos
, ssid
, ssid_len
);
353 /* Supported rates */
354 pos
= hostapd_eid_supp_rates(hapd
, pos
);
357 pos
= hostapd_eid_ds_params(hapd
, pos
);
359 pos
= hostapd_eid_country(hapd
, pos
, epos
- pos
);
361 /* ERP Information element */
362 pos
= hostapd_eid_erp_info(hapd
, pos
);
364 /* Extended supported rates */
365 pos
= hostapd_eid_ext_supp_rates(hapd
, pos
);
368 pos
= hostapd_eid_wpa(hapd
, pos
, epos
- pos
, sta
);
370 #ifdef CONFIG_IEEE80211N
371 pos
= hostapd_eid_ht_capabilities(hapd
, pos
);
372 pos
= hostapd_eid_ht_operation(hapd
, pos
);
373 #endif /* CONFIG_IEEE80211N */
375 /* Wi-Fi Alliance WMM */
376 pos
= hostapd_eid_wmm(hapd
, pos
);
379 if (hapd
->conf
->wps_state
&& hapd
->wps_probe_resp_ie
) {
380 os_memcpy(pos
, wpabuf_head(hapd
->wps_probe_resp_ie
),
381 wpabuf_len(hapd
->wps_probe_resp_ie
));
382 pos
+= wpabuf_len(hapd
->wps_probe_resp_ie
);
384 #endif /* CONFIG_WPS */
387 if ((hapd
->conf
->p2p
& P2P_ENABLED
) && elems
.p2p
&&
388 hapd
->p2p_probe_resp_ie
) {
389 os_memcpy(pos
, wpabuf_head(hapd
->p2p_probe_resp_ie
),
390 wpabuf_len(hapd
->p2p_probe_resp_ie
));
391 pos
+= wpabuf_len(hapd
->p2p_probe_resp_ie
);
393 #endif /* CONFIG_P2P */
394 #ifdef CONFIG_P2P_MANAGER
395 if ((hapd
->conf
->p2p
& (P2P_MANAGE
| P2P_ENABLED
| P2P_GROUP_OWNER
)) ==
397 pos
= hostapd_eid_p2p_manage(hapd
, pos
);
398 #endif /* CONFIG_P2P_MANAGER */
400 if (hapd
->drv
.send_mgmt_frame(hapd
, resp
, pos
- (u8
*) resp
) < 0)
401 perror("handle_probe_req: send");
405 wpa_printf(MSG_EXCESSIVE
, "STA " MACSTR
" sent probe request for %s "
406 "SSID", MAC2STR(mgmt
->sa
),
407 elems
.ssid_len
== 0 ? "broadcast" : "our");
411 void ieee802_11_set_beacon(struct hostapd_data
*hapd
)
413 struct ieee80211_mgmt
*head
;
414 u8
*pos
, *tail
, *tailpos
;
416 size_t head_len
, tail_len
;
419 if ((hapd
->conf
->p2p
& (P2P_ENABLED
| P2P_GROUP_OWNER
)) == P2P_ENABLED
)
421 #endif /* CONFIG_P2P */
423 #define BEACON_HEAD_BUF_SIZE 256
424 #define BEACON_TAIL_BUF_SIZE 512
425 head
= os_zalloc(BEACON_HEAD_BUF_SIZE
);
426 tail_len
= BEACON_TAIL_BUF_SIZE
;
428 if (hapd
->conf
->wps_state
&& hapd
->wps_beacon_ie
)
429 tail_len
+= wpabuf_len(hapd
->wps_beacon_ie
);
430 #endif /* CONFIG_WPS */
432 if (hapd
->p2p_beacon_ie
)
433 tail_len
+= wpabuf_len(hapd
->p2p_beacon_ie
);
434 #endif /* CONFIG_P2P */
435 tailpos
= tail
= os_malloc(tail_len
);
436 if (head
== NULL
|| tail
== NULL
) {
437 wpa_printf(MSG_ERROR
, "Failed to set beacon data");
443 head
->frame_control
= IEEE80211_FC(WLAN_FC_TYPE_MGMT
,
444 WLAN_FC_STYPE_BEACON
);
445 head
->duration
= host_to_le16(0);
446 os_memset(head
->da
, 0xff, ETH_ALEN
);
448 os_memcpy(head
->sa
, hapd
->own_addr
, ETH_ALEN
);
449 os_memcpy(head
->bssid
, hapd
->own_addr
, ETH_ALEN
);
450 head
->u
.beacon
.beacon_int
=
451 host_to_le16(hapd
->iconf
->beacon_int
);
453 /* hardware or low-level driver will setup seq_ctrl and timestamp */
454 capab_info
= hostapd_own_capab_info(hapd
, NULL
, 0);
455 head
->u
.beacon
.capab_info
= host_to_le16(capab_info
);
456 pos
= &head
->u
.beacon
.variable
[0];
459 *pos
++ = WLAN_EID_SSID
;
460 if (hapd
->conf
->ignore_broadcast_ssid
== 2) {
461 /* clear the data, but keep the correct length of the SSID */
462 *pos
++ = hapd
->conf
->ssid
.ssid_len
;
463 os_memset(pos
, 0, hapd
->conf
->ssid
.ssid_len
);
464 pos
+= hapd
->conf
->ssid
.ssid_len
;
465 } else if (hapd
->conf
->ignore_broadcast_ssid
) {
466 *pos
++ = 0; /* empty SSID */
468 *pos
++ = hapd
->conf
->ssid
.ssid_len
;
469 os_memcpy(pos
, hapd
->conf
->ssid
.ssid
,
470 hapd
->conf
->ssid
.ssid_len
);
471 pos
+= hapd
->conf
->ssid
.ssid_len
;
474 /* Supported rates */
475 pos
= hostapd_eid_supp_rates(hapd
, pos
);
478 pos
= hostapd_eid_ds_params(hapd
, pos
);
480 head_len
= pos
- (u8
*) head
;
482 tailpos
= hostapd_eid_country(hapd
, tailpos
,
483 tail
+ BEACON_TAIL_BUF_SIZE
- tailpos
);
485 /* ERP Information element */
486 tailpos
= hostapd_eid_erp_info(hapd
, tailpos
);
488 /* Extended supported rates */
489 tailpos
= hostapd_eid_ext_supp_rates(hapd
, tailpos
);
492 tailpos
= hostapd_eid_wpa(hapd
, tailpos
, tail
+ BEACON_TAIL_BUF_SIZE
-
495 #ifdef CONFIG_IEEE80211N
496 tailpos
= hostapd_eid_ht_capabilities(hapd
, tailpos
);
497 tailpos
= hostapd_eid_ht_operation(hapd
, tailpos
);
498 #endif /* CONFIG_IEEE80211N */
500 /* Wi-Fi Alliance WMM */
501 tailpos
= hostapd_eid_wmm(hapd
, tailpos
);
504 if (hapd
->conf
->wps_state
&& hapd
->wps_beacon_ie
) {
505 os_memcpy(tailpos
, wpabuf_head(hapd
->wps_beacon_ie
),
506 wpabuf_len(hapd
->wps_beacon_ie
));
507 tailpos
+= wpabuf_len(hapd
->wps_beacon_ie
);
509 #endif /* CONFIG_WPS */
512 if ((hapd
->conf
->p2p
& P2P_ENABLED
) && hapd
->p2p_beacon_ie
) {
513 os_memcpy(tailpos
, wpabuf_head(hapd
->p2p_beacon_ie
),
514 wpabuf_len(hapd
->p2p_beacon_ie
));
515 tailpos
+= wpabuf_len(hapd
->p2p_beacon_ie
);
517 #endif /* CONFIG_P2P */
518 #ifdef CONFIG_P2P_MANAGER
519 if ((hapd
->conf
->p2p
& (P2P_MANAGE
| P2P_ENABLED
| P2P_GROUP_OWNER
)) ==
521 tailpos
= hostapd_eid_p2p_manage(hapd
, tailpos
);
522 #endif /* CONFIG_P2P_MANAGER */
524 tail_len
= tailpos
> tail
? tailpos
- tail
: 0;
526 if (hapd
->drv
.set_beacon(hapd
, (u8
*) head
, head_len
,
527 tail
, tail_len
, hapd
->conf
->dtim_period
,
528 hapd
->iconf
->beacon_int
))
529 wpa_printf(MSG_ERROR
, "Failed to set beacon head/tail or DTIM "
537 #endif /* CONFIG_P2P */
538 hapd
->drv
.set_bss_params(hapd
, !!(ieee802_11_erp_info(hapd
) &
539 ERP_INFO_USE_PROTECTION
));
543 void ieee802_11_set_beacons(struct hostapd_iface
*iface
)
546 for (i
= 0; i
< iface
->num_bss
; i
++)
547 ieee802_11_set_beacon(iface
->bss
[i
]);
550 #endif /* CONFIG_NATIVE_WINDOWS */