1 /*
2 * wpa_supplicant - Off-channel Action frame TX/RX
3 * Copyright (c) 2009-2010, Atheros Communications
4 * Copyright (c) 2011, Qualcomm Atheros
5 *
6 * This software may be distributed under the terms of the BSD license.
7 * See README for more details.
8 */
9
10 #include "includes.h"
11
12 #include "common.h"
13 #include "utils/eloop.h"
14 #include "wpa_supplicant_i.h"
15 #include "p2p_supplicant.h"
16 #include "driver_i.h"
17 #include "offchannel.h"
18
19
20
21 static struct wpa_supplicant *
wpas_get_tx_interface(struct wpa_supplicant * wpa_s,const u8 * src)22 wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src)
23 {
24 struct wpa_supplicant *iface;
25
26 if (os_memcmp(src, wpa_s->own_addr, ETH_ALEN) == 0)
27 return wpa_s;
28
29 /*
30 * Try to find a group interface that matches with the source address.
31 */
32 iface = wpa_s->global->ifaces;
33 while (iface) {
34 if (os_memcmp(src, iface->own_addr, ETH_ALEN) == 0)
35 break;
36 iface = iface->next;
37 }
38 if (iface) {
39 wpa_printf(MSG_DEBUG, "P2P: Use group interface %s "
40 "instead of interface %s for Action TX",
41 iface->ifname, wpa_s->ifname);
42 return iface;
43 }
44
45 return wpa_s;
46 }
47
48
wpas_send_action_cb(void * eloop_ctx,void * timeout_ctx)49 static void wpas_send_action_cb(void *eloop_ctx, void *timeout_ctx)
50 {
51 struct wpa_supplicant *wpa_s = eloop_ctx;
52 struct wpa_supplicant *iface;
53 int res;
54 int without_roc;
55
56 without_roc = wpa_s->pending_action_without_roc;
57 wpa_s->pending_action_without_roc = 0;
58 wpa_printf(MSG_DEBUG,
59 "Off-channel: Send Action callback (without_roc=%d pending_action_tx=%p pending_action_tx_done=%d)",
60 without_roc, wpa_s->pending_action_tx,
61 !!wpa_s->pending_action_tx_done);
62
63 if (wpa_s->pending_action_tx == NULL || wpa_s->pending_action_tx_done)
64 return;
65
66 /*
67 * This call is likely going to be on the P2P device instance if the
68 * driver uses a separate interface for that purpose. However, some
69 * Action frames are actually sent within a P2P Group and when that is
70 * the case, we need to follow power saving (e.g., GO buffering the
71 * frame for a client in PS mode or a client following the advertised
72 * NoA from its GO). To make that easier for the driver, select the
73 * correct group interface here.
74 */
75 iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src);
76
77 if (wpa_s->off_channel_freq != wpa_s->pending_action_freq &&
78 wpa_s->pending_action_freq != 0 &&
79 wpa_s->pending_action_freq != iface->assoc_freq) {
80 wpa_printf(MSG_DEBUG, "Off-channel: Pending Action frame TX "
81 "waiting for another freq=%u (off_channel_freq=%u "
82 "assoc_freq=%u)",
83 wpa_s->pending_action_freq,
84 wpa_s->off_channel_freq,
85 iface->assoc_freq);
86 if (without_roc && wpa_s->off_channel_freq == 0) {
87 unsigned int duration = 200;
88 /*
89 * We may get here if wpas_send_action() found us to be
90 * on the correct channel, but remain-on-channel cancel
91 * event was received before getting here.
92 */
93 wpa_printf(MSG_DEBUG, "Off-channel: Schedule "
94 "remain-on-channel to send Action frame");
95 #ifdef CONFIG_TESTING_OPTIONS
96 if (wpa_s->extra_roc_dur) {
97 wpa_printf(MSG_DEBUG,
98 "TESTING: Increase ROC duration %u -> %u",
99 duration,
100 duration + wpa_s->extra_roc_dur);
101 duration += wpa_s->extra_roc_dur;
102 }
103 #endif /* CONFIG_TESTING_OPTIONS */
104 if (wpa_drv_remain_on_channel(
105 wpa_s, wpa_s->pending_action_freq,
106 duration) < 0) {
107 wpa_printf(MSG_DEBUG, "Off-channel: Failed to "
108 "request driver to remain on "
109 "channel (%u MHz) for Action Frame "
110 "TX", wpa_s->pending_action_freq);
111 } else {
112 wpa_s->off_channel_freq = 0;
113 wpa_s->roc_waiting_drv_freq =
114 wpa_s->pending_action_freq;
115 }
116 }
117 return;
118 }
119
120 wpa_printf(MSG_DEBUG, "Off-channel: Sending pending Action frame to "
121 MACSTR " using interface %s",
122 MAC2STR(wpa_s->pending_action_dst), iface->ifname);
123 res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
124 wpa_s->pending_action_dst,
125 wpa_s->pending_action_src,
126 wpa_s->pending_action_bssid,
127 wpabuf_head(wpa_s->pending_action_tx),
128 wpabuf_len(wpa_s->pending_action_tx),
129 wpa_s->pending_action_no_cck);
130 if (res) {
131 wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
132 "pending Action frame");
133 /*
134 * Use fake TX status event to allow state machines to
135 * continue.
136 */
137 offchannel_send_action_tx_status(
138 wpa_s, wpa_s->pending_action_dst,
139 wpabuf_head(wpa_s->pending_action_tx),
140 wpabuf_len(wpa_s->pending_action_tx),
141 OFFCHANNEL_SEND_ACTION_FAILED);
142 }
143 }
144
145
146 /**
147 * offchannel_send_action_tx_status - TX status callback
148 * @wpa_s: Pointer to wpa_supplicant data
149 * @dst: Destination MAC address of the transmitted Action frame
150 * @data: Transmitted frame payload
151 * @data_len: Length of @data in bytes
152 * @result: TX status
153 *
154 * This function is called whenever the driver indicates a TX status event for
155 * a frame sent by offchannel_send_action() using wpa_drv_send_action().
156 */
offchannel_send_action_tx_status(struct wpa_supplicant * wpa_s,const u8 * dst,const u8 * data,size_t data_len,enum offchannel_send_action_result result)157 void offchannel_send_action_tx_status(
158 struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
159 size_t data_len, enum offchannel_send_action_result result)
160 {
161 if (wpa_s->pending_action_tx == NULL) {
162 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
163 "no pending operation");
164 return;
165 }
166
167 if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
168 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
169 "unknown destination address");
170 return;
171 }
172
173 /* Accept report only if the contents of the frame matches */
174 if (data_len - wpabuf_len(wpa_s->pending_action_tx) != 24 ||
175 os_memcmp(data + 24, wpabuf_head(wpa_s->pending_action_tx),
176 wpabuf_len(wpa_s->pending_action_tx)) != 0) {
177 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
178 "mismatching contents with pending frame");
179 wpa_hexdump(MSG_MSGDUMP, "TX status frame data",
180 data, data_len);
181 wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
182 wpa_s->pending_action_tx);
183 return;
184 }
185
186 wpa_printf(MSG_DEBUG, "Off-channel: Delete matching pending action frame");
187
188 wpabuf_free(wpa_s->pending_action_tx);
189 wpa_s->pending_action_tx = NULL;
190
191 wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
192 result, wpa_s->pending_action_tx_status_cb);
193
194 if (wpa_s->pending_action_tx_status_cb) {
195 wpa_s->pending_action_tx_status_cb(
196 wpa_s, wpa_s->pending_action_freq,
197 wpa_s->pending_action_dst, wpa_s->pending_action_src,
198 wpa_s->pending_action_bssid,
199 data, data_len, result);
200 }
201
202 #ifdef CONFIG_P2P
203 if (wpa_s->p2p_long_listen > 0) {
204 /* Continue the listen */
205 wpa_printf(MSG_DEBUG, "P2P: Continuing long Listen state");
206 wpas_p2p_listen_start(wpa_s, wpa_s->p2p_long_listen);
207 }
208 #endif /* CONFIG_P2P */
209 }
210
211
212 /**
213 * offchannel_send_action - Request off-channel Action frame TX
214 * @wpa_s: Pointer to wpa_supplicant data
215 * @freq: The frequency in MHz indicating the channel on which the frame is to
216 * transmitted or 0 for the current channel (only if associated)
217 * @dst: Action frame destination MAC address
218 * @src: Action frame source MAC address
219 * @bssid: Action frame BSSID
220 * @buf: Frame to transmit starting from the Category field
221 * @len: Length of @buf in bytes
222 * @wait_time: Wait time for response in milliseconds
223 * @tx_cb: Callback function for indicating TX status or %NULL for now callback
224 * @no_cck: Whether CCK rates are to be disallowed for TX rate selection
225 * Returns: 0 on success or -1 on failure
226 *
227 * This function is used to request an Action frame to be transmitted on the
228 * current operating channel or on another channel (off-channel). The actual
229 * frame transmission will be delayed until the driver is ready on the specified
230 * channel. The @wait_time parameter can be used to request the driver to remain
231 * awake on the channel to wait for a response.
232 */
offchannel_send_action(struct wpa_supplicant * wpa_s,unsigned int freq,const u8 * dst,const u8 * src,const u8 * bssid,const u8 * buf,size_t len,unsigned int wait_time,void (* tx_cb)(struct wpa_supplicant * wpa_s,unsigned int freq,const u8 * dst,const u8 * src,const u8 * bssid,const u8 * data,size_t data_len,enum offchannel_send_action_result result),int no_cck)233 int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
234 const u8 *dst, const u8 *src, const u8 *bssid,
235 const u8 *buf, size_t len, unsigned int wait_time,
236 void (*tx_cb)(struct wpa_supplicant *wpa_s,
237 unsigned int freq, const u8 *dst,
238 const u8 *src, const u8 *bssid,
239 const u8 *data, size_t data_len,
240 enum offchannel_send_action_result
241 result),
242 int no_cck)
243 {
244 wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
245 MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
246 freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
247 (int) len);
248
249 wpa_s->pending_action_tx_status_cb = tx_cb;
250
251 if (wpa_s->pending_action_tx) {
252 wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
253 "frame TX to " MACSTR,
254 MAC2STR(wpa_s->pending_action_dst));
255 wpabuf_free(wpa_s->pending_action_tx);
256 }
257 wpa_s->pending_action_tx_done = 0;
258 wpa_s->pending_action_tx = wpabuf_alloc(len);
259 if (wpa_s->pending_action_tx == NULL) {
260 wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
261 "frame TX buffer (len=%llu)",
262 (unsigned long long) len);
263 return -1;
264 }
265 wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
266 os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
267 os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
268 os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
269 wpa_s->pending_action_freq = freq;
270 wpa_s->pending_action_no_cck = no_cck;
271
272 if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
273 struct wpa_supplicant *iface;
274 int ret;
275
276 iface = wpas_get_tx_interface(wpa_s, src);
277 wpa_s->action_tx_wait_time = wait_time;
278
279 ret = wpa_drv_send_action(
280 iface, wpa_s->pending_action_freq,
281 wait_time, wpa_s->pending_action_dst,
282 wpa_s->pending_action_src, wpa_s->pending_action_bssid,
283 wpabuf_head(wpa_s->pending_action_tx),
284 wpabuf_len(wpa_s->pending_action_tx),
285 wpa_s->pending_action_no_cck);
286 if (ret == 0)
287 wpa_s->pending_action_tx_done = 1;
288 return ret;
289 }
290
291 if (freq) {
292 struct wpa_supplicant *tx_iface;
293 tx_iface = wpas_get_tx_interface(wpa_s, src);
294 if (tx_iface->assoc_freq == freq) {
295 wpa_printf(MSG_DEBUG, "Off-channel: Already on "
296 "requested channel (TX interface operating "
297 "channel)");
298 freq = 0;
299 }
300 }
301
302 if (wpa_s->off_channel_freq == freq || freq == 0) {
303 wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
304 "channel; send Action frame immediately");
305 /* TODO: Would there ever be need to extend the current
306 * duration on the channel? */
307 wpa_s->pending_action_without_roc = 1;
308 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
309 eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
310 return 0;
311 }
312 wpa_s->pending_action_without_roc = 0;
313
314 if (wpa_s->roc_waiting_drv_freq == freq) {
315 wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
316 "driver to get to frequency %u MHz; continue "
317 "waiting to send the Action frame", freq);
318 return 0;
319 }
320
321 wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
322 "transmitted once the driver gets to the requested "
323 "channel");
324 if (wait_time > wpa_s->max_remain_on_chan)
325 wait_time = wpa_s->max_remain_on_chan;
326 else if (wait_time == 0)
327 wait_time = 20;
328 #ifdef CONFIG_TESTING_OPTIONS
329 if (wpa_s->extra_roc_dur) {
330 wpa_printf(MSG_DEBUG, "TESTING: Increase ROC duration %u -> %u",
331 wait_time, wait_time + wpa_s->extra_roc_dur);
332 wait_time += wpa_s->extra_roc_dur;
333 }
334 #endif /* CONFIG_TESTING_OPTIONS */
335 if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
336 wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
337 "to remain on channel (%u MHz) for Action "
338 "Frame TX", freq);
339 return -1;
340 }
341 wpa_s->off_channel_freq = 0;
342 wpa_s->roc_waiting_drv_freq = freq;
343
344 return 0;
345 }
346
347
348 /**
349 * offchannel_send_send_action_done - Notify completion of Action frame sequence
350 * @wpa_s: Pointer to wpa_supplicant data
351 *
352 * This function can be used to cancel a wait for additional response frames on
353 * the channel that was used with offchannel_send_action().
354 */
offchannel_send_action_done(struct wpa_supplicant * wpa_s)355 void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
356 {
357 wpa_printf(MSG_DEBUG,
358 "Off-channel: Action frame sequence done notification: pending_action_tx=%p drv_offchan_tx=%d action_tx_wait_time=%d off_channel_freq=%d roc_waiting_drv_freq=%d",
359 wpa_s->pending_action_tx,
360 !!(wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX),
361 wpa_s->action_tx_wait_time, wpa_s->off_channel_freq,
362 wpa_s->roc_waiting_drv_freq);
363 wpabuf_free(wpa_s->pending_action_tx);
364 wpa_s->pending_action_tx = NULL;
365 if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
366 wpa_s->action_tx_wait_time)
367 wpa_drv_send_action_cancel_wait(wpa_s);
368 else if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
369 wpa_drv_cancel_remain_on_channel(wpa_s);
370 wpa_s->off_channel_freq = 0;
371 wpa_s->roc_waiting_drv_freq = 0;
372 }
373 }
374
375
376 /**
377 * offchannel_remain_on_channel_cb - Remain-on-channel callback function
378 * @wpa_s: Pointer to wpa_supplicant data
379 * @freq: Frequency (in MHz) of the selected channel
380 * @duration: Duration of the remain-on-channel operation in milliseconds
381 *
382 * This function is called whenever the driver notifies beginning of a
383 * remain-on-channel operation.
384 */
offchannel_remain_on_channel_cb(struct wpa_supplicant * wpa_s,unsigned int freq,unsigned int duration)385 void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
386 unsigned int freq, unsigned int duration)
387 {
388 wpa_s->roc_waiting_drv_freq = 0;
389 wpa_s->off_channel_freq = freq;
390 wpas_send_action_cb(wpa_s, NULL);
391 }
392
393
394 /**
395 * offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
396 * @wpa_s: Pointer to wpa_supplicant data
397 * @freq: Frequency (in MHz) of the selected channel
398 *
399 * This function is called whenever the driver notifies termination of a
400 * remain-on-channel operation.
401 */
offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant * wpa_s,unsigned int freq)402 void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
403 unsigned int freq)
404 {
405 wpa_s->off_channel_freq = 0;
406 }
407
408
409 /**
410 * offchannel_pending_action_tx - Check whether there is a pending Action TX
411 * @wpa_s: Pointer to wpa_supplicant data
412 * Returns: Pointer to pending frame or %NULL if no pending operation
413 *
414 * This function can be used to check whether there is a pending Action frame TX
415 * operation. The returned pointer should be used only for checking whether it
416 * is %NULL (no pending frame) or to print the pointer value in debug
417 * information (i.e., the pointer should not be dereferenced).
418 */
offchannel_pending_action_tx(struct wpa_supplicant * wpa_s)419 const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
420 {
421 return wpa_s->pending_action_tx;
422 }
423
424
425 /**
426 * offchannel_clear_pending_action_tx - Clear pending Action frame TX
427 * @wpa_s: Pointer to wpa_supplicant data
428 */
offchannel_clear_pending_action_tx(struct wpa_supplicant * wpa_s)429 void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
430 {
431 wpabuf_free(wpa_s->pending_action_tx);
432 wpa_s->pending_action_tx = NULL;
433 }
434
435
436 /**
437 * offchannel_deinit - Deinit off-channel operations
438 * @wpa_s: Pointer to wpa_supplicant data
439 *
440 * This function is used to free up any allocated resources for off-channel
441 * operations.
442 */
offchannel_deinit(struct wpa_supplicant * wpa_s)443 void offchannel_deinit(struct wpa_supplicant *wpa_s)
444 {
445 offchannel_clear_pending_action_tx(wpa_s);
446 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
447 }
448