• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 (pending_action_tx=%p)",
122 		   MAC2STR(wpa_s->pending_action_dst), iface->ifname,
123 		   wpa_s->pending_action_tx);
124 	res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
125 				  wpa_s->pending_action_dst,
126 				  wpa_s->pending_action_src,
127 				  wpa_s->pending_action_bssid,
128 				  wpabuf_head(wpa_s->pending_action_tx),
129 				  wpabuf_len(wpa_s->pending_action_tx),
130 				  wpa_s->pending_action_no_cck);
131 	if (res) {
132 		wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
133 			   "pending Action frame");
134 		/*
135 		 * Use fake TX status event to allow state machines to
136 		 * continue.
137 		 */
138 		offchannel_send_action_tx_status(
139 			wpa_s, wpa_s->pending_action_dst,
140 			wpabuf_head(wpa_s->pending_action_tx),
141 			wpabuf_len(wpa_s->pending_action_tx),
142 			OFFCHANNEL_SEND_ACTION_FAILED);
143 	}
144 }
145 
146 
147 /**
148  * offchannel_send_action_tx_status - TX status callback
149  * @wpa_s: Pointer to wpa_supplicant data
150  * @dst: Destination MAC address of the transmitted Action frame
151  * @data: Transmitted frame payload
152  * @data_len: Length of @data in bytes
153  * @result: TX status
154  *
155  * This function is called whenever the driver indicates a TX status event for
156  * a frame sent by offchannel_send_action() using wpa_drv_send_action().
157  */
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)158 void offchannel_send_action_tx_status(
159 	struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
160 	size_t data_len, enum offchannel_send_action_result result)
161 {
162 	if (wpa_s->pending_action_tx == NULL) {
163 		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
164 			   "no pending operation");
165 		return;
166 	}
167 
168 	if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
169 		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
170 			   "unknown destination address");
171 		return;
172 	}
173 
174 	/* Accept report only if the contents of the frame matches */
175 	if (data_len - wpabuf_len(wpa_s->pending_action_tx) != 24 ||
176 	    os_memcmp(data + 24, wpabuf_head(wpa_s->pending_action_tx),
177 		      wpabuf_len(wpa_s->pending_action_tx)) != 0) {
178 		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
179 				   "mismatching contents with pending frame");
180 		wpa_hexdump(MSG_MSGDUMP, "TX status frame data",
181 			    data, data_len);
182 		wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
183 				wpa_s->pending_action_tx);
184 		return;
185 	}
186 
187 	wpa_printf(MSG_DEBUG,
188 		   "Off-channel: Delete matching pending action frame (dst="
189 		   MACSTR " pending_action_tx=%p)", MAC2STR(dst),
190 		   wpa_s->pending_action_tx);
191 	wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
192 			wpa_s->pending_action_tx);
193 	wpabuf_free(wpa_s->pending_action_tx);
194 	wpa_s->pending_action_tx = NULL;
195 
196 	wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
197 		   result, wpa_s->pending_action_tx_status_cb);
198 
199 	if (wpa_s->pending_action_tx_status_cb) {
200 		wpa_s->pending_action_tx_status_cb(
201 			wpa_s, wpa_s->pending_action_freq,
202 			wpa_s->pending_action_dst, wpa_s->pending_action_src,
203 			wpa_s->pending_action_bssid,
204 			data, data_len, result);
205 	}
206 
207 #ifdef CONFIG_P2P
208 	if (wpa_s->p2p_long_listen > 0) {
209 		/* Continue the listen */
210 		wpa_printf(MSG_DEBUG, "P2P: Continuing long Listen state");
211 		wpas_p2p_listen_start(wpa_s, wpa_s->p2p_long_listen);
212 	}
213 #endif /* CONFIG_P2P */
214 }
215 
216 
217 /**
218  * offchannel_send_action - Request off-channel Action frame TX
219  * @wpa_s: Pointer to wpa_supplicant data
220  * @freq: The frequency in MHz indicating the channel on which the frame is to
221  *	transmitted or 0 for the current channel (only if associated)
222  * @dst: Action frame destination MAC address
223  * @src: Action frame source MAC address
224  * @bssid: Action frame BSSID
225  * @buf: Frame to transmit starting from the Category field
226  * @len: Length of @buf in bytes
227  * @wait_time: Wait time for response in milliseconds
228  * @tx_cb: Callback function for indicating TX status or %NULL for now callback
229  * @no_cck: Whether CCK rates are to be disallowed for TX rate selection
230  * Returns: 0 on success or -1 on failure
231  *
232  * This function is used to request an Action frame to be transmitted on the
233  * current operating channel or on another channel (off-channel). The actual
234  * frame transmission will be delayed until the driver is ready on the specified
235  * channel. The @wait_time parameter can be used to request the driver to remain
236  * awake on the channel to wait for a response.
237  */
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)238 int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
239 			   const u8 *dst, const u8 *src, const u8 *bssid,
240 			   const u8 *buf, size_t len, unsigned int wait_time,
241 			   void (*tx_cb)(struct wpa_supplicant *wpa_s,
242 					 unsigned int freq, const u8 *dst,
243 					 const u8 *src, const u8 *bssid,
244 					 const u8 *data, size_t data_len,
245 					 enum offchannel_send_action_result
246 					 result),
247 			   int no_cck)
248 {
249 	wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
250 		   MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
251 		   freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
252 		   (int) len);
253 
254 	wpa_s->pending_action_tx_status_cb = tx_cb;
255 
256 	if (wpa_s->pending_action_tx) {
257 		wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
258 			   "frame TX to " MACSTR " (pending_action_tx=%p)",
259 			   MAC2STR(wpa_s->pending_action_dst),
260 			   wpa_s->pending_action_tx);
261 		wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
262 				wpa_s->pending_action_tx);
263 		wpabuf_free(wpa_s->pending_action_tx);
264 	}
265 	wpa_s->pending_action_tx_done = 0;
266 	wpa_s->pending_action_tx = wpabuf_alloc(len);
267 	if (wpa_s->pending_action_tx == NULL) {
268 		wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
269 			   "frame TX buffer (len=%llu)",
270 			   (unsigned long long) len);
271 		return -1;
272 	}
273 	wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
274 	os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
275 	os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
276 	os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
277 	wpa_s->pending_action_freq = freq;
278 	wpa_s->pending_action_no_cck = no_cck;
279 	wpa_printf(MSG_DEBUG,
280 		   "Off-channel: Stored pending action frame (dst=" MACSTR
281 		   " pending_action_tx=%p)",
282 		   MAC2STR(dst), wpa_s->pending_action_tx);
283 	wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
284 			wpa_s->pending_action_tx);
285 
286 	if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
287 		struct wpa_supplicant *iface;
288 		int ret;
289 
290 		iface = wpas_get_tx_interface(wpa_s, src);
291 		wpa_s->action_tx_wait_time = wait_time;
292 
293 		ret = wpa_drv_send_action(
294 			iface, wpa_s->pending_action_freq,
295 			wait_time, wpa_s->pending_action_dst,
296 			wpa_s->pending_action_src, wpa_s->pending_action_bssid,
297 			wpabuf_head(wpa_s->pending_action_tx),
298 			wpabuf_len(wpa_s->pending_action_tx),
299 			wpa_s->pending_action_no_cck);
300 		if (ret == 0)
301 			wpa_s->pending_action_tx_done = 1;
302 		return ret;
303 	}
304 
305 	if (freq) {
306 		struct wpa_supplicant *tx_iface;
307 		tx_iface = wpas_get_tx_interface(wpa_s, src);
308 		if (tx_iface->assoc_freq == freq) {
309 			wpa_printf(MSG_DEBUG, "Off-channel: Already on "
310 				   "requested channel (TX interface operating "
311 				   "channel)");
312 			freq = 0;
313 		}
314 	}
315 
316 	if (wpa_s->off_channel_freq == freq || freq == 0) {
317 		wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
318 			   "channel; send Action frame immediately");
319 		/* TODO: Would there ever be need to extend the current
320 		 * duration on the channel? */
321 		wpa_s->pending_action_without_roc = 1;
322 		eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
323 		eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
324 		return 0;
325 	}
326 	wpa_s->pending_action_without_roc = 0;
327 
328 	if (wpa_s->roc_waiting_drv_freq == freq) {
329 		wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
330 			   "driver to get to frequency %u MHz; continue "
331 			   "waiting to send the Action frame", freq);
332 		return 0;
333 	}
334 
335 	wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
336 		   "transmitted once the driver gets to the requested "
337 		   "channel");
338 	if (wait_time > wpa_s->max_remain_on_chan)
339 		wait_time = wpa_s->max_remain_on_chan;
340 	else if (wait_time == 0)
341 		wait_time = 20;
342 #ifdef CONFIG_TESTING_OPTIONS
343 	if (wpa_s->extra_roc_dur) {
344 		wpa_printf(MSG_DEBUG, "TESTING: Increase ROC duration %u -> %u",
345 			   wait_time, wait_time + wpa_s->extra_roc_dur);
346 		wait_time += wpa_s->extra_roc_dur;
347 	}
348 #endif /* CONFIG_TESTING_OPTIONS */
349 	if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
350 		wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
351 			   "to remain on channel (%u MHz) for Action "
352 			   "Frame TX", freq);
353 		return -1;
354 	}
355 	wpa_s->off_channel_freq = 0;
356 	wpa_s->roc_waiting_drv_freq = freq;
357 
358 	return 0;
359 }
360 
361 
362 /**
363  * offchannel_send_send_action_done - Notify completion of Action frame sequence
364  * @wpa_s: Pointer to wpa_supplicant data
365  *
366  * This function can be used to cancel a wait for additional response frames on
367  * the channel that was used with offchannel_send_action().
368  */
offchannel_send_action_done(struct wpa_supplicant * wpa_s)369 void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
370 {
371 	wpa_printf(MSG_DEBUG,
372 		   "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",
373 		   wpa_s->pending_action_tx,
374 		   !!(wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX),
375 		   wpa_s->action_tx_wait_time, wpa_s->off_channel_freq,
376 		   wpa_s->roc_waiting_drv_freq);
377 	wpabuf_free(wpa_s->pending_action_tx);
378 	wpa_s->pending_action_tx = NULL;
379 	if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
380 	    wpa_s->action_tx_wait_time)
381 		wpa_drv_send_action_cancel_wait(wpa_s);
382 	else if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
383 		wpa_drv_cancel_remain_on_channel(wpa_s);
384 		wpa_s->off_channel_freq = 0;
385 		wpa_s->roc_waiting_drv_freq = 0;
386 	}
387 }
388 
389 
390 /**
391  * offchannel_remain_on_channel_cb - Remain-on-channel callback function
392  * @wpa_s: Pointer to wpa_supplicant data
393  * @freq: Frequency (in MHz) of the selected channel
394  * @duration: Duration of the remain-on-channel operation in milliseconds
395  *
396  * This function is called whenever the driver notifies beginning of a
397  * remain-on-channel operation.
398  */
offchannel_remain_on_channel_cb(struct wpa_supplicant * wpa_s,unsigned int freq,unsigned int duration)399 void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
400 				     unsigned int freq, unsigned int duration)
401 {
402 	wpa_s->roc_waiting_drv_freq = 0;
403 	wpa_s->off_channel_freq = freq;
404 	wpas_send_action_cb(wpa_s, NULL);
405 }
406 
407 
408 /**
409  * offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
410  * @wpa_s: Pointer to wpa_supplicant data
411  * @freq: Frequency (in MHz) of the selected channel
412  *
413  * This function is called whenever the driver notifies termination of a
414  * remain-on-channel operation.
415  */
offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant * wpa_s,unsigned int freq)416 void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
417 					    unsigned int freq)
418 {
419 	wpa_s->off_channel_freq = 0;
420 }
421 
422 
423 /**
424  * offchannel_pending_action_tx - Check whether there is a pending Action TX
425  * @wpa_s: Pointer to wpa_supplicant data
426  * Returns: Pointer to pending frame or %NULL if no pending operation
427  *
428  * This function can be used to check whether there is a pending Action frame TX
429  * operation. The returned pointer should be used only for checking whether it
430  * is %NULL (no pending frame) or to print the pointer value in debug
431  * information (i.e., the pointer should not be dereferenced).
432  */
offchannel_pending_action_tx(struct wpa_supplicant * wpa_s)433 const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
434 {
435 	return wpa_s->pending_action_tx;
436 }
437 
438 
439 /**
440  * offchannel_clear_pending_action_tx - Clear pending Action frame TX
441  * @wpa_s: Pointer to wpa_supplicant data
442  */
offchannel_clear_pending_action_tx(struct wpa_supplicant * wpa_s)443 void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
444 {
445 	wpa_printf(MSG_DEBUG,
446 		   "Off-channel: Clear pending Action frame TX (pending_action_tx=%p",
447 		   wpa_s->pending_action_tx);
448 	wpabuf_free(wpa_s->pending_action_tx);
449 	wpa_s->pending_action_tx = NULL;
450 }
451 
452 
453 /**
454  * offchannel_deinit - Deinit off-channel operations
455  * @wpa_s: Pointer to wpa_supplicant data
456  *
457  * This function is used to free up any allocated resources for off-channel
458  * operations.
459  */
offchannel_deinit(struct wpa_supplicant * wpa_s)460 void offchannel_deinit(struct wpa_supplicant *wpa_s)
461 {
462 	offchannel_clear_pending_action_tx(wpa_s);
463 	eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
464 }
465