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 "driver_i.h" 16 #include "offchannel.h" 17 18 19 20 static struct wpa_supplicant * 21 wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src) 22 { 23 struct wpa_supplicant *iface; 24 25 if (os_memcmp(src, wpa_s->own_addr, ETH_ALEN) == 0) 26 return wpa_s; 27 28 /* 29 * Try to find a group interface that matches with the source address. 30 */ 31 iface = wpa_s->global->ifaces; 32 while (iface) { 33 if (os_memcmp(wpa_s->pending_action_src, 34 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 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, "Off-channel: Send Action callback " 59 "(without_roc=%d pending_action_tx=%p)", 60 without_roc, wpa_s->pending_action_tx); 61 62 if (wpa_s->pending_action_tx == NULL) 63 return; 64 65 /* 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. 73 */ 74 iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src); 75 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 " 81 "assoc_freq=%u)", 82 wpa_s->pending_action_freq, 83 wpa_s->off_channel_freq, 84 iface->assoc_freq); 85 if (without_roc && wpa_s->off_channel_freq == 0) { 86 /* 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. 90 */ 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) < 95 0) { 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); 100 } else { 101 wpa_s->off_channel_freq = 0; 102 wpa_s->roc_waiting_drv_freq = 103 wpa_s->pending_action_freq; 104 } 105 } 106 return; 107 } 108 109 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); 119 if (res) { 120 wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the " 121 "pending Action frame"); 122 /* 123 * Use fake TX status event to allow state machines to 124 * continue. 125 */ 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); 131 } 132 } 133 134 135 /** 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 141 * @result: TX status 142 * 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(). 145 */ 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) 149 { 150 if (wpa_s->pending_action_tx == NULL) { 151 wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - " 152 "no pending operation"); 153 return; 154 } 155 156 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"); 159 return; 160 } 161 162 wpabuf_free(wpa_s->pending_action_tx); 163 wpa_s->pending_action_tx = NULL; 164 165 wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p", 166 result, wpa_s->pending_action_tx_status_cb); 167 168 if (wpa_s->pending_action_tx_status_cb) { 169 wpa_s->pending_action_tx_status_cb( 170 wpa_s, wpa_s->pending_action_freq, 171 wpa_s->pending_action_dst, wpa_s->pending_action_src, 172 wpa_s->pending_action_bssid, 173 data, data_len, result); 174 } 175 } 176 177 178 /** 179 * offchannel_send_action - Request off-channel Action frame TX 180 * @wpa_s: Pointer to wpa_supplicant data 181 * @freq: The frequency in MHz indicating the channel on which the frame is to 182 * transmitted or 0 for the current channel (only if associated) 183 * @dst: Action frame destination MAC address 184 * @src: Action frame source MAC address 185 * @bssid: Action frame BSSID 186 * @buf: Frame to transmit starting from the Category field 187 * @len: Length of @buf in bytes 188 * @wait_time: Wait time for response in milliseconds 189 * @tx_cb: Callback function for indicating TX status or %NULL for now callback 190 * @no_cck: Whether CCK rates are to be disallowed for TX rate selection 191 * Returns: 0 on success or -1 on failure 192 * 193 * This function is used to request an Action frame to be transmitted on the 194 * current operating channel or on another channel (off-channel). The actual 195 * frame transmission will be delayed until the driver is ready on the specified 196 * channel. The @wait_time parameter can be used to request the driver to remain 197 * awake on the channel to wait for a response. 198 */ 199 int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq, 200 const u8 *dst, const u8 *src, const u8 *bssid, 201 const u8 *buf, size_t len, unsigned int wait_time, 202 void (*tx_cb)(struct wpa_supplicant *wpa_s, 203 unsigned int freq, const u8 *dst, 204 const u8 *src, const u8 *bssid, 205 const u8 *data, size_t data_len, 206 enum offchannel_send_action_result 207 result), 208 int no_cck) 209 { 210 wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst=" 211 MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d", 212 freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid), 213 (int) len); 214 215 wpa_s->pending_action_tx_status_cb = tx_cb; 216 217 if (wpa_s->pending_action_tx) { 218 wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action " 219 "frame TX to " MACSTR, 220 MAC2STR(wpa_s->pending_action_dst)); 221 wpabuf_free(wpa_s->pending_action_tx); 222 } 223 wpa_s->pending_action_tx = wpabuf_alloc(len); 224 if (wpa_s->pending_action_tx == NULL) { 225 wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action " 226 "frame TX buffer (len=%llu)", 227 (unsigned long long) len); 228 return -1; 229 } 230 wpabuf_put_data(wpa_s->pending_action_tx, buf, len); 231 os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN); 232 os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN); 233 os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN); 234 wpa_s->pending_action_freq = freq; 235 wpa_s->pending_action_no_cck = no_cck; 236 237 if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) { 238 struct wpa_supplicant *iface; 239 240 iface = wpas_get_tx_interface(wpa_s, 241 wpa_s->pending_action_src); 242 wpa_s->action_tx_wait_time = wait_time; 243 244 return wpa_drv_send_action( 245 iface, wpa_s->pending_action_freq, 246 wait_time, wpa_s->pending_action_dst, 247 wpa_s->pending_action_src, wpa_s->pending_action_bssid, 248 wpabuf_head(wpa_s->pending_action_tx), 249 wpabuf_len(wpa_s->pending_action_tx), 250 wpa_s->pending_action_no_cck); 251 } 252 253 if (freq) { 254 struct wpa_supplicant *tx_iface; 255 tx_iface = wpas_get_tx_interface(wpa_s, src); 256 if (tx_iface->assoc_freq == freq) { 257 wpa_printf(MSG_DEBUG, "Off-channel: Already on " 258 "requested channel (TX interface operating " 259 "channel)"); 260 freq = 0; 261 } 262 } 263 264 if (wpa_s->off_channel_freq == freq || freq == 0) { 265 wpa_printf(MSG_DEBUG, "Off-channel: Already on requested " 266 "channel; send Action frame immediately"); 267 /* TODO: Would there ever be need to extend the current 268 * duration on the channel? */ 269 wpa_s->pending_action_without_roc = 1; 270 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL); 271 eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL); 272 return 0; 273 } 274 wpa_s->pending_action_without_roc = 0; 275 276 if (wpa_s->roc_waiting_drv_freq == freq) { 277 wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for " 278 "driver to get to frequency %u MHz; continue " 279 "waiting to send the Action frame", freq); 280 return 0; 281 } 282 283 wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be " 284 "transmitted once the driver gets to the requested " 285 "channel"); 286 if (wait_time > wpa_s->max_remain_on_chan) 287 wait_time = wpa_s->max_remain_on_chan; 288 if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) { 289 wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver " 290 "to remain on channel (%u MHz) for Action " 291 "Frame TX", freq); 292 return -1; 293 } 294 wpa_s->off_channel_freq = 0; 295 wpa_s->roc_waiting_drv_freq = freq; 296 297 return 0; 298 } 299 300 301 /** 302 * offchannel_send_send_action_done - Notify completion of Action frame sequence 303 * @wpa_s: Pointer to wpa_supplicant data 304 * 305 * This function can be used to cancel a wait for additional response frames on 306 * the channel that was used with offchannel_send_action(). 307 */ 308 void offchannel_send_action_done(struct wpa_supplicant *wpa_s) 309 { 310 wpa_printf(MSG_DEBUG, "Off-channel: Action frame sequence done " 311 "notification"); 312 wpabuf_free(wpa_s->pending_action_tx); 313 wpa_s->pending_action_tx = NULL; 314 if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX && 315 wpa_s->action_tx_wait_time) 316 wpa_drv_send_action_cancel_wait(wpa_s); 317 318 if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) { 319 wpa_drv_cancel_remain_on_channel(wpa_s); 320 wpa_s->off_channel_freq = 0; 321 wpa_s->roc_waiting_drv_freq = 0; 322 } 323 } 324 325 326 /** 327 * offchannel_remain_on_channel_cb - Remain-on-channel callback function 328 * @wpa_s: Pointer to wpa_supplicant data 329 * @freq: Frequency (in MHz) of the selected channel 330 * @duration: Duration of the remain-on-channel operation in milliseconds 331 * 332 * This function is called whenever the driver notifies beginning of a 333 * remain-on-channel operation. 334 */ 335 void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s, 336 unsigned int freq, unsigned int duration) 337 { 338 wpa_s->roc_waiting_drv_freq = 0; 339 wpa_s->off_channel_freq = freq; 340 wpas_send_action_cb(wpa_s, NULL); 341 } 342 343 344 /** 345 * offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback 346 * @wpa_s: Pointer to wpa_supplicant data 347 * @freq: Frequency (in MHz) of the selected channel 348 * 349 * This function is called whenever the driver notifies termination of a 350 * remain-on-channel operation. 351 */ 352 void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s, 353 unsigned int freq) 354 { 355 wpa_s->off_channel_freq = 0; 356 } 357 358 359 /** 360 * offchannel_pending_action_tx - Check whether there is a pending Action TX 361 * @wpa_s: Pointer to wpa_supplicant data 362 * Returns: Pointer to pending frame or %NULL if no pending operation 363 * 364 * This function can be used to check whether there is a pending Action frame TX 365 * operation. The returned pointer should be used only for checking whether it 366 * is %NULL (no pending frame) or to print the pointer value in debug 367 * information (i.e., the pointer should not be dereferenced). 368 */ 369 const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s) 370 { 371 return wpa_s->pending_action_tx; 372 } 373 374 375 /** 376 * offchannel_clear_pending_action_tx - Clear pending Action frame TX 377 * @wpa_s: Pointer to wpa_supplicant data 378 */ 379 void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s) 380 { 381 wpabuf_free(wpa_s->pending_action_tx); 382 wpa_s->pending_action_tx = NULL; 383 } 384 385 386 /** 387 * offchannel_deinit - Deinit off-channel operations 388 * @wpa_s: Pointer to wpa_supplicant data 389 * 390 * This function is used to free up any allocated resources for off-channel 391 * operations. 392 */ 393 void offchannel_deinit(struct wpa_supplicant *wpa_s) 394 { 395 offchannel_clear_pending_action_tx(wpa_s); 396 eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL); 397 } 398