2 * wpa_supplicant - Off-channel Action frame TX/RX
3 * Copyright (c) 2009-2010, Atheros Communications
4 * Copyright (c) 2011, Qualcomm Atheros
6 * This software may be distributed under the terms of the BSD license.
7 * See README for more details.
13 #include "utils/eloop.h"
14 #include "wpa_supplicant_i.h"
16 #include "offchannel.h"
20 static struct wpa_supplicant *
21 wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src)
23 struct wpa_supplicant *iface;
25 if (os_memcmp(src, wpa_s->own_addr, ETH_ALEN) == 0)
29 * Try to find a group interface that matches with the source address.
31 iface = wpa_s->global->ifaces;
33 if (os_memcmp(wpa_s->pending_action_src,
34 iface->own_addr, ETH_ALEN) == 0)
39 wpa_printf(MSG_DEBUG, "P2P: Use group interface %s "
40 "instead of interface %s for Action TX",
41 iface->ifname, wpa_s->ifname);
49 static void wpas_send_action_cb(void *eloop_ctx, void *timeout_ctx)
51 struct wpa_supplicant *wpa_s = eloop_ctx;
52 struct wpa_supplicant *iface;
56 without_roc = wpa_s->pending_action_without_roc;
57 wpa_s->pending_action_without_roc = 0;
58 wpa_printf(MSG_DEBUG, "Off-channel: Send Action callback "
59 "(without_roc=%d pending_action_tx=%p)",
60 without_roc, wpa_s->pending_action_tx);
62 if (wpa_s->pending_action_tx == NULL)
66 * This call is likely going to be on the P2P device instance if the
67 * driver uses a separate interface for that purpose. However, some
68 * Action frames are actually sent within a P2P Group and when that is
69 * the case, we need to follow power saving (e.g., GO buffering the
70 * frame for a client in PS mode or a client following the advertised
71 * NoA from its GO). To make that easier for the driver, select the
72 * correct group interface here.
74 iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src);
76 if (wpa_s->off_channel_freq != wpa_s->pending_action_freq &&
77 wpa_s->pending_action_freq != 0 &&
78 wpa_s->pending_action_freq != iface->assoc_freq) {
79 wpa_printf(MSG_DEBUG, "Off-channel: Pending Action frame TX "
80 "waiting for another freq=%u (off_channel_freq=%u "
82 wpa_s->pending_action_freq,
83 wpa_s->off_channel_freq,
85 if (without_roc && wpa_s->off_channel_freq == 0) {
87 * We may get here if wpas_send_action() found us to be
88 * on the correct channel, but remain-on-channel cancel
89 * event was received before getting here.
91 wpa_printf(MSG_DEBUG, "Off-channel: Schedule "
92 "remain-on-channel to send Action frame");
93 if (wpa_drv_remain_on_channel(
94 wpa_s, wpa_s->pending_action_freq, 200) <
96 wpa_printf(MSG_DEBUG, "Off-channel: Failed to "
97 "request driver to remain on "
98 "channel (%u MHz) for Action Frame "
99 "TX", wpa_s->pending_action_freq);
101 wpa_s->off_channel_freq = 0;
102 wpa_s->roc_waiting_drv_freq =
103 wpa_s->pending_action_freq;
109 wpa_printf(MSG_DEBUG, "Off-channel: Sending pending Action frame to "
110 MACSTR " using interface %s",
111 MAC2STR(wpa_s->pending_action_dst), iface->ifname);
112 res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
113 wpa_s->pending_action_dst,
114 wpa_s->pending_action_src,
115 wpa_s->pending_action_bssid,
116 wpabuf_head(wpa_s->pending_action_tx),
117 wpabuf_len(wpa_s->pending_action_tx),
118 wpa_s->pending_action_no_cck);
120 wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
121 "pending Action frame");
123 * Use fake TX status event to allow state machines to
126 offchannel_send_action_tx_status(
127 wpa_s, wpa_s->pending_action_dst,
128 wpabuf_head(wpa_s->pending_action_tx),
129 wpabuf_len(wpa_s->pending_action_tx),
130 OFFCHANNEL_SEND_ACTION_FAILED);
136 * offchannel_send_action_tx_status - TX status callback
137 * @wpa_s: Pointer to wpa_supplicant data
138 * @dst: Destination MAC address of the transmitted Action frame
139 * @data: Transmitted frame payload
140 * @data_len: Length of @data in bytes
143 * This function is called whenever the driver indicates a TX status event for
144 * a frame sent by offchannel_send_action() using wpa_drv_send_action().
146 void offchannel_send_action_tx_status(
147 struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
148 size_t data_len, enum offchannel_send_action_result result)
150 if (wpa_s->pending_action_tx == NULL) {
151 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
152 "no pending operation");
156 if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
157 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
158 "unknown destination address");
162 /* Accept report only if the contents of the frame matches */
163 if (data_len - wpabuf_len(wpa_s->pending_action_tx) != 24 ||
164 os_memcmp(data + 24, wpabuf_head(wpa_s->pending_action_tx),
165 wpabuf_len(wpa_s->pending_action_tx)) != 0) {
166 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
167 "mismatching contents with pending frame");
168 wpa_hexdump(MSG_MSGDUMP, "TX status frame data",
170 wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
171 wpa_s->pending_action_tx);
175 wpa_printf(MSG_DEBUG, "Off-channel: Delete matching pending action frame");
177 wpabuf_free(wpa_s->pending_action_tx);
178 wpa_s->pending_action_tx = NULL;
180 wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
181 result, wpa_s->pending_action_tx_status_cb);
183 if (wpa_s->pending_action_tx_status_cb) {
184 wpa_s->pending_action_tx_status_cb(
185 wpa_s, wpa_s->pending_action_freq,
186 wpa_s->pending_action_dst, wpa_s->pending_action_src,
187 wpa_s->pending_action_bssid,
188 data, data_len, result);
194 * offchannel_send_action - Request off-channel Action frame TX
195 * @wpa_s: Pointer to wpa_supplicant data
196 * @freq: The frequency in MHz indicating the channel on which the frame is to
197 * transmitted or 0 for the current channel (only if associated)
198 * @dst: Action frame destination MAC address
199 * @src: Action frame source MAC address
200 * @bssid: Action frame BSSID
201 * @buf: Frame to transmit starting from the Category field
202 * @len: Length of @buf in bytes
203 * @wait_time: Wait time for response in milliseconds
204 * @tx_cb: Callback function for indicating TX status or %NULL for now callback
205 * @no_cck: Whether CCK rates are to be disallowed for TX rate selection
206 * Returns: 0 on success or -1 on failure
208 * This function is used to request an Action frame to be transmitted on the
209 * current operating channel or on another channel (off-channel). The actual
210 * frame transmission will be delayed until the driver is ready on the specified
211 * channel. The @wait_time parameter can be used to request the driver to remain
212 * awake on the channel to wait for a response.
214 int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
215 const u8 *dst, const u8 *src, const u8 *bssid,
216 const u8 *buf, size_t len, unsigned int wait_time,
217 void (*tx_cb)(struct wpa_supplicant *wpa_s,
218 unsigned int freq, const u8 *dst,
219 const u8 *src, const u8 *bssid,
220 const u8 *data, size_t data_len,
221 enum offchannel_send_action_result
225 wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
226 MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
227 freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
230 wpa_s->pending_action_tx_status_cb = tx_cb;
232 if (wpa_s->pending_action_tx) {
233 wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
234 "frame TX to " MACSTR,
235 MAC2STR(wpa_s->pending_action_dst));
236 wpabuf_free(wpa_s->pending_action_tx);
238 wpa_s->pending_action_tx = wpabuf_alloc(len);
239 if (wpa_s->pending_action_tx == NULL) {
240 wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
241 "frame TX buffer (len=%llu)",
242 (unsigned long long) len);
245 wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
246 os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
247 os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
248 os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
249 wpa_s->pending_action_freq = freq;
250 wpa_s->pending_action_no_cck = no_cck;
252 if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
253 struct wpa_supplicant *iface;
255 iface = wpas_get_tx_interface(wpa_s,
256 wpa_s->pending_action_src);
257 wpa_s->action_tx_wait_time = wait_time;
259 return wpa_drv_send_action(
260 iface, wpa_s->pending_action_freq,
261 wait_time, wpa_s->pending_action_dst,
262 wpa_s->pending_action_src, wpa_s->pending_action_bssid,
263 wpabuf_head(wpa_s->pending_action_tx),
264 wpabuf_len(wpa_s->pending_action_tx),
265 wpa_s->pending_action_no_cck);
269 struct wpa_supplicant *tx_iface;
270 tx_iface = wpas_get_tx_interface(wpa_s, src);
271 if (tx_iface->assoc_freq == freq) {
272 wpa_printf(MSG_DEBUG, "Off-channel: Already on "
273 "requested channel (TX interface operating "
279 if (wpa_s->off_channel_freq == freq || freq == 0) {
280 wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
281 "channel; send Action frame immediately");
282 /* TODO: Would there ever be need to extend the current
283 * duration on the channel? */
284 wpa_s->pending_action_without_roc = 1;
285 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
286 eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
289 wpa_s->pending_action_without_roc = 0;
291 if (wpa_s->roc_waiting_drv_freq == freq) {
292 wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
293 "driver to get to frequency %u MHz; continue "
294 "waiting to send the Action frame", freq);
298 wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
299 "transmitted once the driver gets to the requested "
301 if (wait_time > wpa_s->max_remain_on_chan)
302 wait_time = wpa_s->max_remain_on_chan;
303 else if (wait_time == 0)
305 if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
306 wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
307 "to remain on channel (%u MHz) for Action "
311 wpa_s->off_channel_freq = 0;
312 wpa_s->roc_waiting_drv_freq = freq;
319 * offchannel_send_send_action_done - Notify completion of Action frame sequence
320 * @wpa_s: Pointer to wpa_supplicant data
322 * This function can be used to cancel a wait for additional response frames on
323 * the channel that was used with offchannel_send_action().
325 void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
327 wpa_printf(MSG_DEBUG, "Off-channel: Action frame sequence done "
329 wpabuf_free(wpa_s->pending_action_tx);
330 wpa_s->pending_action_tx = NULL;
331 if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
332 wpa_s->action_tx_wait_time)
333 wpa_drv_send_action_cancel_wait(wpa_s);
335 if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
336 wpa_drv_cancel_remain_on_channel(wpa_s);
337 wpa_s->off_channel_freq = 0;
338 wpa_s->roc_waiting_drv_freq = 0;
344 * offchannel_remain_on_channel_cb - Remain-on-channel callback function
345 * @wpa_s: Pointer to wpa_supplicant data
346 * @freq: Frequency (in MHz) of the selected channel
347 * @duration: Duration of the remain-on-channel operation in milliseconds
349 * This function is called whenever the driver notifies beginning of a
350 * remain-on-channel operation.
352 void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
353 unsigned int freq, unsigned int duration)
355 wpa_s->roc_waiting_drv_freq = 0;
356 wpa_s->off_channel_freq = freq;
357 wpas_send_action_cb(wpa_s, NULL);
362 * offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
363 * @wpa_s: Pointer to wpa_supplicant data
364 * @freq: Frequency (in MHz) of the selected channel
366 * This function is called whenever the driver notifies termination of a
367 * remain-on-channel operation.
369 void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
372 wpa_s->off_channel_freq = 0;
377 * offchannel_pending_action_tx - Check whether there is a pending Action TX
378 * @wpa_s: Pointer to wpa_supplicant data
379 * Returns: Pointer to pending frame or %NULL if no pending operation
381 * This function can be used to check whether there is a pending Action frame TX
382 * operation. The returned pointer should be used only for checking whether it
383 * is %NULL (no pending frame) or to print the pointer value in debug
384 * information (i.e., the pointer should not be dereferenced).
386 const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
388 return wpa_s->pending_action_tx;
393 * offchannel_clear_pending_action_tx - Clear pending Action frame TX
394 * @wpa_s: Pointer to wpa_supplicant data
396 void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
398 wpabuf_free(wpa_s->pending_action_tx);
399 wpa_s->pending_action_tx = NULL;
404 * offchannel_deinit - Deinit off-channel operations
405 * @wpa_s: Pointer to wpa_supplicant data
407 * This function is used to free up any allocated resources for off-channel
410 void offchannel_deinit(struct wpa_supplicant *wpa_s)
412 offchannel_clear_pending_action_tx(wpa_s);
413 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);