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