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
21static struct wpa_supplicant *
22wpas_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#ifdef CONFIG_P2P
28		if (wpa_s->p2p_mgmt && wpa_s != wpa_s->parent &&
29		    wpa_s->parent->ap_iface &&
30		    os_memcmp(wpa_s->parent->own_addr,
31			      wpa_s->own_addr, ETH_ALEN) == 0 &&
32		    wpabuf_len(wpa_s->pending_action_tx) >= 2 &&
33		    *wpabuf_head_u8(wpa_s->pending_action_tx) !=
34		    WLAN_ACTION_PUBLIC) {
35			/*
36			 * When P2P Device interface has same MAC address as
37			 * the GO interface, make sure non-Public Action frames
38			 * are sent through the GO interface. The P2P Device
39			 * interface can only send Public Action frames.
40			 */
41			wpa_printf(MSG_DEBUG,
42				   "P2P: Use GO interface %s instead of interface %s for Action TX",
43				   wpa_s->parent->ifname, wpa_s->ifname);
44			return wpa_s->parent;
45		}
46#endif /* CONFIG_P2P */
47		return wpa_s;
48	}
49
50	/*
51	 * Try to find a group interface that matches with the source address.
52	 */
53	iface = wpa_s->global->ifaces;
54	while (iface) {
55		if (os_memcmp(src, iface->own_addr, ETH_ALEN) == 0)
56			break;
57		iface = iface->next;
58	}
59	if (iface) {
60		wpa_printf(MSG_DEBUG, "P2P: Use group interface %s "
61			   "instead of interface %s for Action TX",
62			   iface->ifname, wpa_s->ifname);
63		return iface;
64	}
65
66	return wpa_s;
67}
68
69
70static void wpas_send_action_cb(void *eloop_ctx, void *timeout_ctx)
71{
72	struct wpa_supplicant *wpa_s = eloop_ctx;
73	struct wpa_supplicant *iface;
74	int res;
75	int without_roc;
76
77	without_roc = wpa_s->pending_action_without_roc;
78	wpa_s->pending_action_without_roc = 0;
79	wpa_printf(MSG_DEBUG,
80		   "Off-channel: Send Action callback (without_roc=%d pending_action_tx=%p pending_action_tx_done=%d)",
81		   without_roc, wpa_s->pending_action_tx,
82		   !!wpa_s->pending_action_tx_done);
83
84	if (wpa_s->pending_action_tx == NULL || wpa_s->pending_action_tx_done)
85		return;
86
87	/*
88	 * This call is likely going to be on the P2P device instance if the
89	 * driver uses a separate interface for that purpose. However, some
90	 * Action frames are actually sent within a P2P Group and when that is
91	 * the case, we need to follow power saving (e.g., GO buffering the
92	 * frame for a client in PS mode or a client following the advertised
93	 * NoA from its GO). To make that easier for the driver, select the
94	 * correct group interface here.
95	 */
96	iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src);
97
98	if (wpa_s->off_channel_freq != wpa_s->pending_action_freq &&
99	    wpa_s->pending_action_freq != 0 &&
100	    wpa_s->pending_action_freq != iface->assoc_freq) {
101		wpa_printf(MSG_DEBUG, "Off-channel: Pending Action frame TX "
102			   "waiting for another freq=%u (off_channel_freq=%u "
103			   "assoc_freq=%u)",
104			   wpa_s->pending_action_freq,
105			   wpa_s->off_channel_freq,
106			   iface->assoc_freq);
107		if (without_roc && wpa_s->off_channel_freq == 0) {
108			unsigned int duration = 200;
109			/*
110			 * We may get here if wpas_send_action() found us to be
111			 * on the correct channel, but remain-on-channel cancel
112			 * event was received before getting here.
113			 */
114			wpa_printf(MSG_DEBUG, "Off-channel: Schedule "
115				   "remain-on-channel to send Action frame");
116#ifdef CONFIG_TESTING_OPTIONS
117			if (wpa_s->extra_roc_dur) {
118				wpa_printf(MSG_DEBUG,
119					   "TESTING: Increase ROC duration %u -> %u",
120					   duration,
121					   duration + wpa_s->extra_roc_dur);
122				duration += wpa_s->extra_roc_dur;
123	}
124#endif /* CONFIG_TESTING_OPTIONS */
125			if (wpa_drv_remain_on_channel(
126				    wpa_s, wpa_s->pending_action_freq,
127				    duration) < 0) {
128				wpa_printf(MSG_DEBUG, "Off-channel: Failed to "
129					   "request driver to remain on "
130					   "channel (%u MHz) for Action Frame "
131					   "TX", wpa_s->pending_action_freq);
132			} else {
133				wpa_s->off_channel_freq = 0;
134				wpa_s->roc_waiting_drv_freq =
135					wpa_s->pending_action_freq;
136			}
137		}
138		return;
139	}
140
141	wpa_printf(MSG_DEBUG, "Off-channel: Sending pending Action frame to "
142		   MACSTR " using interface %s (pending_action_tx=%p)",
143		   MAC2STR(wpa_s->pending_action_dst), iface->ifname,
144		   wpa_s->pending_action_tx);
145	res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
146				  wpa_s->pending_action_dst,
147				  wpa_s->pending_action_src,
148				  wpa_s->pending_action_bssid,
149				  wpabuf_head(wpa_s->pending_action_tx),
150				  wpabuf_len(wpa_s->pending_action_tx),
151				  wpa_s->pending_action_no_cck);
152	if (res) {
153		wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
154			   "pending Action frame");
155		/*
156		 * Use fake TX status event to allow state machines to
157		 * continue.
158		 */
159		offchannel_send_action_tx_status(
160			wpa_s, wpa_s->pending_action_dst,
161			wpabuf_head(wpa_s->pending_action_tx),
162			wpabuf_len(wpa_s->pending_action_tx),
163			OFFCHANNEL_SEND_ACTION_FAILED);
164	}
165}
166
167
168/**
169 * offchannel_send_action_tx_status - TX status callback
170 * @wpa_s: Pointer to wpa_supplicant data
171 * @dst: Destination MAC address of the transmitted Action frame
172 * @data: Transmitted frame payload
173 * @data_len: Length of @data in bytes
174 * @result: TX status
175 *
176 * This function is called whenever the driver indicates a TX status event for
177 * a frame sent by offchannel_send_action() using wpa_drv_send_action().
178 */
179void offchannel_send_action_tx_status(
180	struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
181	size_t data_len, enum offchannel_send_action_result result)
182{
183	if (wpa_s->pending_action_tx == NULL) {
184		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
185			   "no pending operation");
186		return;
187	}
188
189	if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
190		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
191			   "unknown destination address");
192		return;
193	}
194
195	/* Accept report only if the contents of the frame matches */
196	if (data_len - wpabuf_len(wpa_s->pending_action_tx) != 24 ||
197	    os_memcmp(data + 24, wpabuf_head(wpa_s->pending_action_tx),
198		      wpabuf_len(wpa_s->pending_action_tx)) != 0) {
199		wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
200				   "mismatching contents with pending frame");
201		wpa_hexdump(MSG_MSGDUMP, "TX status frame data",
202			    data, data_len);
203		wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
204				wpa_s->pending_action_tx);
205		return;
206	}
207
208	wpa_printf(MSG_DEBUG,
209		   "Off-channel: Delete matching pending action frame (dst="
210		   MACSTR " pending_action_tx=%p)", MAC2STR(dst),
211		   wpa_s->pending_action_tx);
212	wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
213			wpa_s->pending_action_tx);
214	wpabuf_free(wpa_s->pending_action_tx);
215	wpa_s->pending_action_tx = NULL;
216
217	wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
218		   result, wpa_s->pending_action_tx_status_cb);
219
220	if (wpa_s->pending_action_tx_status_cb) {
221		wpa_s->pending_action_tx_status_cb(
222			wpa_s, wpa_s->pending_action_freq,
223			wpa_s->pending_action_dst, wpa_s->pending_action_src,
224			wpa_s->pending_action_bssid,
225			data, data_len, result);
226	}
227
228#ifdef CONFIG_P2P
229	if (wpa_s->p2p_long_listen > 0) {
230		/* Continue the listen */
231		wpa_printf(MSG_DEBUG, "P2P: Continuing long Listen state");
232		wpas_p2p_listen_start(wpa_s, wpa_s->p2p_long_listen);
233	}
234#endif /* CONFIG_P2P */
235}
236
237
238/**
239 * offchannel_send_action - Request off-channel Action frame TX
240 * @wpa_s: Pointer to wpa_supplicant data
241 * @freq: The frequency in MHz indicating the channel on which the frame is to
242 *	transmitted or 0 for the current channel (only if associated)
243 * @dst: Action frame destination MAC address
244 * @src: Action frame source MAC address
245 * @bssid: Action frame BSSID
246 * @buf: Frame to transmit starting from the Category field
247 * @len: Length of @buf in bytes
248 * @wait_time: Wait time for response in milliseconds
249 * @tx_cb: Callback function for indicating TX status or %NULL for now callback
250 * @no_cck: Whether CCK rates are to be disallowed for TX rate selection
251 * Returns: 0 on success or -1 on failure
252 *
253 * This function is used to request an Action frame to be transmitted on the
254 * current operating channel or on another channel (off-channel). The actual
255 * frame transmission will be delayed until the driver is ready on the specified
256 * channel. The @wait_time parameter can be used to request the driver to remain
257 * awake on the channel to wait for a response.
258 */
259int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
260			   const u8 *dst, const u8 *src, const u8 *bssid,
261			   const u8 *buf, size_t len, unsigned int wait_time,
262			   void (*tx_cb)(struct wpa_supplicant *wpa_s,
263					 unsigned int freq, const u8 *dst,
264					 const u8 *src, const u8 *bssid,
265					 const u8 *data, size_t data_len,
266					 enum offchannel_send_action_result
267					 result),
268			   int no_cck)
269{
270	wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
271		   MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
272		   freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
273		   (int) len);
274
275	wpa_s->pending_action_tx_status_cb = tx_cb;
276
277	if (wpa_s->pending_action_tx) {
278		wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
279			   "frame TX to " MACSTR " (pending_action_tx=%p)",
280			   MAC2STR(wpa_s->pending_action_dst),
281			   wpa_s->pending_action_tx);
282		wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
283				wpa_s->pending_action_tx);
284		wpabuf_free(wpa_s->pending_action_tx);
285	}
286	wpa_s->pending_action_tx_done = 0;
287	wpa_s->pending_action_tx = wpabuf_alloc(len);
288	if (wpa_s->pending_action_tx == NULL) {
289		wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
290			   "frame TX buffer (len=%llu)",
291			   (unsigned long long) len);
292		return -1;
293	}
294	wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
295	os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
296	os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
297	os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
298	wpa_s->pending_action_freq = freq;
299	wpa_s->pending_action_no_cck = no_cck;
300	wpa_printf(MSG_DEBUG,
301		   "Off-channel: Stored pending action frame (dst=" MACSTR
302		   " pending_action_tx=%p)",
303		   MAC2STR(dst), wpa_s->pending_action_tx);
304	wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
305			wpa_s->pending_action_tx);
306
307	if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
308		struct wpa_supplicant *iface;
309		int ret;
310
311		iface = wpas_get_tx_interface(wpa_s, src);
312		wpa_s->action_tx_wait_time = wait_time;
313		if (wait_time)
314			wpa_s->action_tx_wait_time_used = 1;
315
316		ret = wpa_drv_send_action(
317			iface, wpa_s->pending_action_freq,
318			wait_time, wpa_s->pending_action_dst,
319			wpa_s->pending_action_src, wpa_s->pending_action_bssid,
320			wpabuf_head(wpa_s->pending_action_tx),
321			wpabuf_len(wpa_s->pending_action_tx),
322			wpa_s->pending_action_no_cck);
323		if (ret == 0)
324			wpa_s->pending_action_tx_done = 1;
325		return ret;
326	}
327
328	if (freq) {
329		struct wpa_supplicant *tx_iface;
330		tx_iface = wpas_get_tx_interface(wpa_s, src);
331		if (tx_iface->assoc_freq == freq) {
332			wpa_printf(MSG_DEBUG, "Off-channel: Already on "
333				   "requested channel (TX interface operating "
334				   "channel)");
335			freq = 0;
336		}
337	}
338
339	if (wpa_s->off_channel_freq == freq || freq == 0) {
340		wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
341			   "channel; send Action frame immediately");
342		/* TODO: Would there ever be need to extend the current
343		 * duration on the channel? */
344		wpa_s->pending_action_without_roc = 1;
345		eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
346		eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
347		return 0;
348	}
349	wpa_s->pending_action_without_roc = 0;
350
351	if (wpa_s->roc_waiting_drv_freq == freq) {
352		wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
353			   "driver to get to frequency %u MHz; continue "
354			   "waiting to send the Action frame", freq);
355		return 0;
356	}
357
358	wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
359		   "transmitted once the driver gets to the requested "
360		   "channel");
361	if (wait_time > wpa_s->max_remain_on_chan)
362		wait_time = wpa_s->max_remain_on_chan;
363	else if (wait_time == 0)
364		wait_time = 20;
365#ifdef CONFIG_TESTING_OPTIONS
366	if (wpa_s->extra_roc_dur) {
367		wpa_printf(MSG_DEBUG, "TESTING: Increase ROC duration %u -> %u",
368			   wait_time, wait_time + wpa_s->extra_roc_dur);
369		wait_time += wpa_s->extra_roc_dur;
370	}
371#endif /* CONFIG_TESTING_OPTIONS */
372	if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
373		wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
374			   "to remain on channel (%u MHz) for Action "
375			   "Frame TX", freq);
376		return -1;
377	}
378	wpa_s->off_channel_freq = 0;
379	wpa_s->roc_waiting_drv_freq = freq;
380
381	return 0;
382}
383
384
385/**
386 * offchannel_send_send_action_done - Notify completion of Action frame sequence
387 * @wpa_s: Pointer to wpa_supplicant data
388 *
389 * This function can be used to cancel a wait for additional response frames on
390 * the channel that was used with offchannel_send_action().
391 */
392void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
393{
394	wpa_printf(MSG_DEBUG,
395		   "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",
396		   wpa_s->pending_action_tx,
397		   !!(wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX),
398		   wpa_s->action_tx_wait_time, wpa_s->off_channel_freq,
399		   wpa_s->roc_waiting_drv_freq);
400	wpabuf_free(wpa_s->pending_action_tx);
401	wpa_s->pending_action_tx = NULL;
402	if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
403	    (wpa_s->action_tx_wait_time || wpa_s->action_tx_wait_time_used))
404		wpa_drv_send_action_cancel_wait(wpa_s);
405	else if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
406		wpa_drv_cancel_remain_on_channel(wpa_s);
407		wpa_s->off_channel_freq = 0;
408		wpa_s->roc_waiting_drv_freq = 0;
409	}
410	wpa_s->action_tx_wait_time_used = 0;
411}
412
413
414/**
415 * offchannel_remain_on_channel_cb - Remain-on-channel callback function
416 * @wpa_s: Pointer to wpa_supplicant data
417 * @freq: Frequency (in MHz) of the selected channel
418 * @duration: Duration of the remain-on-channel operation in milliseconds
419 *
420 * This function is called whenever the driver notifies beginning of a
421 * remain-on-channel operation.
422 */
423void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
424				     unsigned int freq, unsigned int duration)
425{
426	wpa_s->roc_waiting_drv_freq = 0;
427	wpa_s->off_channel_freq = freq;
428	wpas_send_action_cb(wpa_s, NULL);
429}
430
431
432/**
433 * offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
434 * @wpa_s: Pointer to wpa_supplicant data
435 * @freq: Frequency (in MHz) of the selected channel
436 *
437 * This function is called whenever the driver notifies termination of a
438 * remain-on-channel operation.
439 */
440void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
441					    unsigned int freq)
442{
443	wpa_s->off_channel_freq = 0;
444}
445
446
447/**
448 * offchannel_pending_action_tx - Check whether there is a pending Action TX
449 * @wpa_s: Pointer to wpa_supplicant data
450 * Returns: Pointer to pending frame or %NULL if no pending operation
451 *
452 * This function can be used to check whether there is a pending Action frame TX
453 * operation. The returned pointer should be used only for checking whether it
454 * is %NULL (no pending frame) or to print the pointer value in debug
455 * information (i.e., the pointer should not be dereferenced).
456 */
457const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
458{
459	return wpa_s->pending_action_tx;
460}
461
462
463/**
464 * offchannel_clear_pending_action_tx - Clear pending Action frame TX
465 * @wpa_s: Pointer to wpa_supplicant data
466 */
467void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
468{
469	wpa_printf(MSG_DEBUG,
470		   "Off-channel: Clear pending Action frame TX (pending_action_tx=%p",
471		   wpa_s->pending_action_tx);
472	wpabuf_free(wpa_s->pending_action_tx);
473	wpa_s->pending_action_tx = NULL;
474}
475
476
477/**
478 * offchannel_deinit - Deinit off-channel operations
479 * @wpa_s: Pointer to wpa_supplicant data
480 *
481 * This function is used to free up any allocated resources for off-channel
482 * operations.
483 */
484void offchannel_deinit(struct wpa_supplicant *wpa_s)
485{
486	offchannel_clear_pending_action_tx(wpa_s);
487	eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
488}
489