1 /* 2 * Wi-Fi Direct - P2P Invitation procedure 3 * Copyright (c) 2010, Atheros Communications 4 * 5 * This software may be distributed under the terms of the BSD license. 6 * See README for more details. 7 */ 8 9 #include "includes.h" 10 11 #include "common.h" 12 #include "common/ieee802_11_defs.h" 13 #include "p2p_i.h" 14 #include "p2p.h" 15 16 17 static struct wpabuf * p2p_build_invitation_req(struct p2p_data *p2p, 18 struct p2p_device *peer, 19 const u8 *go_dev_addr) 20 { 21 struct wpabuf *buf; 22 u8 *len; 23 const u8 *dev_addr; 24 size_t extra = 0; 25 26 #ifdef CONFIG_WIFI_DISPLAY 27 struct wpabuf *wfd_ie = p2p->wfd_ie_invitation; 28 if (wfd_ie && p2p->inv_role == P2P_INVITE_ROLE_ACTIVE_GO) { 29 size_t i; 30 for (i = 0; i < p2p->num_groups; i++) { 31 struct p2p_group *g = p2p->groups[i]; 32 struct wpabuf *ie; 33 if (os_memcmp(p2p_group_get_interface_addr(g), 34 p2p->inv_bssid, ETH_ALEN) != 0) 35 continue; 36 ie = p2p_group_get_wfd_ie(g); 37 if (ie) { 38 wfd_ie = ie; 39 break; 40 } 41 } 42 } 43 if (wfd_ie) 44 extra = wpabuf_len(wfd_ie); 45 #endif /* CONFIG_WIFI_DISPLAY */ 46 47 buf = wpabuf_alloc(1000 + extra); 48 if (buf == NULL) 49 return NULL; 50 51 peer->dialog_token++; 52 if (peer->dialog_token == 0) 53 peer->dialog_token = 1; 54 p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_REQ, 55 peer->dialog_token); 56 57 len = p2p_buf_add_ie_hdr(buf); 58 if (p2p->inv_role == P2P_INVITE_ROLE_ACTIVE_GO || !p2p->inv_persistent) 59 p2p_buf_add_config_timeout(buf, 0, 0); 60 else 61 p2p_buf_add_config_timeout(buf, p2p->go_timeout, 62 p2p->client_timeout); 63 p2p_buf_add_invitation_flags(buf, p2p->inv_persistent ? 64 P2P_INVITATION_FLAGS_TYPE : 0); 65 if (p2p->inv_role != P2P_INVITE_ROLE_CLIENT || 66 !(peer->flags & P2P_DEV_NO_PREF_CHAN)) 67 p2p_buf_add_operating_channel(buf, p2p->cfg->country, 68 p2p->op_reg_class, 69 p2p->op_channel); 70 if (p2p->inv_bssid_set) 71 p2p_buf_add_group_bssid(buf, p2p->inv_bssid); 72 p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels); 73 if (go_dev_addr) 74 dev_addr = go_dev_addr; 75 else if (p2p->inv_role == P2P_INVITE_ROLE_CLIENT) 76 dev_addr = peer->info.p2p_device_addr; 77 else 78 dev_addr = p2p->cfg->dev_addr; 79 p2p_buf_add_group_id(buf, dev_addr, p2p->inv_ssid, p2p->inv_ssid_len); 80 p2p_buf_add_device_info(buf, p2p, peer); 81 p2p_buf_update_ie_hdr(buf, len); 82 83 #ifdef CONFIG_WIFI_DISPLAY 84 if (wfd_ie) 85 wpabuf_put_buf(buf, wfd_ie); 86 #endif /* CONFIG_WIFI_DISPLAY */ 87 88 return buf; 89 } 90 91 92 static struct wpabuf * p2p_build_invitation_resp(struct p2p_data *p2p, 93 struct p2p_device *peer, 94 u8 dialog_token, u8 status, 95 const u8 *group_bssid, 96 u8 reg_class, u8 channel, 97 struct p2p_channels *channels) 98 { 99 struct wpabuf *buf; 100 u8 *len; 101 size_t extra = 0; 102 103 #ifdef CONFIG_WIFI_DISPLAY 104 struct wpabuf *wfd_ie = p2p->wfd_ie_invitation; 105 if (wfd_ie && group_bssid) { 106 size_t i; 107 for (i = 0; i < p2p->num_groups; i++) { 108 struct p2p_group *g = p2p->groups[i]; 109 struct wpabuf *ie; 110 if (os_memcmp(p2p_group_get_interface_addr(g), 111 group_bssid, ETH_ALEN) != 0) 112 continue; 113 ie = p2p_group_get_wfd_ie(g); 114 if (ie) { 115 wfd_ie = ie; 116 break; 117 } 118 } 119 } 120 if (wfd_ie) 121 extra = wpabuf_len(wfd_ie); 122 #endif /* CONFIG_WIFI_DISPLAY */ 123 124 buf = wpabuf_alloc(1000 + extra); 125 if (buf == NULL) 126 return NULL; 127 128 p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_RESP, 129 dialog_token); 130 131 len = p2p_buf_add_ie_hdr(buf); 132 p2p_buf_add_status(buf, status); 133 p2p_buf_add_config_timeout(buf, 0, 0); /* FIX */ 134 if (reg_class && channel) 135 p2p_buf_add_operating_channel(buf, p2p->cfg->country, 136 reg_class, channel); 137 if (group_bssid) 138 p2p_buf_add_group_bssid(buf, group_bssid); 139 if (channels) 140 p2p_buf_add_channel_list(buf, p2p->cfg->country, channels); 141 p2p_buf_update_ie_hdr(buf, len); 142 143 #ifdef CONFIG_WIFI_DISPLAY 144 if (wfd_ie) 145 wpabuf_put_buf(buf, wfd_ie); 146 #endif /* CONFIG_WIFI_DISPLAY */ 147 148 return buf; 149 } 150 151 152 void p2p_process_invitation_req(struct p2p_data *p2p, const u8 *sa, 153 const u8 *data, size_t len, int rx_freq) 154 { 155 struct p2p_device *dev; 156 struct p2p_message msg; 157 struct wpabuf *resp = NULL; 158 u8 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; 159 int freq; 160 int go = 0; 161 u8 group_bssid[ETH_ALEN], *bssid; 162 int op_freq = 0; 163 u8 reg_class = 0, channel = 0; 164 struct p2p_channels intersection, *channels = NULL; 165 int persistent; 166 167 os_memset(group_bssid, 0, sizeof(group_bssid)); 168 169 p2p_dbg(p2p, "Received Invitation Request from " MACSTR " (freq=%d)", 170 MAC2STR(sa), rx_freq); 171 172 if (p2p_parse(data, len, &msg)) 173 return; 174 175 dev = p2p_get_device(p2p, sa); 176 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { 177 p2p_dbg(p2p, "Invitation Request from unknown peer " MACSTR, 178 MAC2STR(sa)); 179 180 if (p2p_add_device(p2p, sa, rx_freq, NULL, 0, data + 1, len - 1, 181 0)) { 182 p2p_dbg(p2p, "Invitation Request add device failed " 183 MACSTR, MAC2STR(sa)); 184 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; 185 goto fail; 186 } 187 188 dev = p2p_get_device(p2p, sa); 189 if (dev == NULL) { 190 p2p_dbg(p2p, "Reject Invitation Request from unknown peer " 191 MACSTR, MAC2STR(sa)); 192 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; 193 goto fail; 194 } 195 } 196 197 if (!msg.group_id || !msg.channel_list) { 198 p2p_dbg(p2p, "Mandatory attribute missing in Invitation Request from " 199 MACSTR, MAC2STR(sa)); 200 status = P2P_SC_FAIL_INVALID_PARAMS; 201 goto fail; 202 } 203 204 if (msg.invitation_flags) 205 persistent = *msg.invitation_flags & P2P_INVITATION_FLAGS_TYPE; 206 else { 207 /* Invitation Flags is a mandatory attribute starting from P2P 208 * spec 1.06. As a backwards compatibility mechanism, assume 209 * the request was for a persistent group if the attribute is 210 * missing. 211 */ 212 p2p_dbg(p2p, "Mandatory Invitation Flags attribute missing from Invitation Request"); 213 persistent = 1; 214 } 215 216 if (p2p_peer_channels_check(p2p, &p2p->cfg->channels, dev, 217 msg.channel_list, msg.channel_list_len) < 218 0) { 219 p2p_dbg(p2p, "No common channels found"); 220 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 221 goto fail; 222 } 223 224 p2p_channels_intersect(&p2p->cfg->channels, &dev->channels, 225 &intersection); 226 227 if (p2p->cfg->invitation_process) { 228 status = p2p->cfg->invitation_process( 229 p2p->cfg->cb_ctx, sa, msg.group_bssid, msg.group_id, 230 msg.group_id + ETH_ALEN, msg.group_id_len - ETH_ALEN, 231 &go, group_bssid, &op_freq, persistent, &intersection); 232 } 233 234 if (op_freq) { 235 p2p_dbg(p2p, "Invitation processing forced frequency %d MHz", 236 op_freq); 237 if (p2p_freq_to_channel(op_freq, ®_class, &channel) < 0) { 238 p2p_dbg(p2p, "Unknown forced freq %d MHz from invitation_process()", 239 op_freq); 240 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 241 goto fail; 242 } 243 244 if (!p2p_channels_includes(&intersection, reg_class, channel)) 245 { 246 p2p_dbg(p2p, "forced freq %d MHz not in the supported channels interaction", 247 op_freq); 248 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 249 goto fail; 250 } 251 252 if (status == P2P_SC_SUCCESS) 253 channels = &intersection; 254 } else { 255 p2p_dbg(p2p, "No forced channel from invitation processing - figure out best one to use"); 256 257 /* Default to own configuration as a starting point */ 258 p2p->op_reg_class = p2p->cfg->op_reg_class; 259 p2p->op_channel = p2p->cfg->op_channel; 260 p2p_dbg(p2p, "Own default op_class %d channel %d", 261 p2p->op_reg_class, p2p->op_channel); 262 263 /* Use peer preference if specified and compatible */ 264 if (msg.operating_channel) { 265 int req_freq; 266 req_freq = p2p_channel_to_freq( 267 msg.operating_channel[3], 268 msg.operating_channel[4]); 269 p2p_dbg(p2p, "Peer operating channel preference: %d MHz", 270 req_freq); 271 if (req_freq > 0 && 272 p2p_channels_includes(&intersection, 273 msg.operating_channel[3], 274 msg.operating_channel[4])) { 275 p2p->op_reg_class = msg.operating_channel[3]; 276 p2p->op_channel = msg.operating_channel[4]; 277 p2p_dbg(p2p, "Use peer preference op_class %d channel %d", 278 p2p->op_reg_class, p2p->op_channel); 279 } else { 280 p2p_dbg(p2p, "Cannot use peer channel preference"); 281 } 282 } 283 284 if (!p2p_channels_includes(&intersection, p2p->op_reg_class, 285 p2p->op_channel)) { 286 p2p_dbg(p2p, "Initially selected channel (op_class %d channel %d) not in channel intersection - try to reselect", 287 p2p->op_reg_class, p2p->op_channel); 288 p2p_reselect_channel(p2p, &intersection); 289 p2p_dbg(p2p, "Re-selection result: op_class %d channel %d", 290 p2p->op_reg_class, p2p->op_channel); 291 if (!p2p_channels_includes(&intersection, 292 p2p->op_reg_class, 293 p2p->op_channel)) { 294 p2p_dbg(p2p, "Peer does not support selected operating channel (reg_class=%u channel=%u)", 295 p2p->op_reg_class, p2p->op_channel); 296 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 297 goto fail; 298 } 299 } else if (!(dev->flags & P2P_DEV_FORCE_FREQ) && 300 !p2p->cfg->cfg_op_channel) { 301 p2p_dbg(p2p, "Try to reselect channel selection with peer information received; previously selected op_class %u channel %u", 302 p2p->op_reg_class, p2p->op_channel); 303 p2p_reselect_channel(p2p, &intersection); 304 } 305 306 op_freq = p2p_channel_to_freq(p2p->op_reg_class, 307 p2p->op_channel); 308 if (op_freq < 0) { 309 p2p_dbg(p2p, "Unknown operational channel (country=%c%c reg_class=%u channel=%u)", 310 p2p->cfg->country[0], p2p->cfg->country[1], 311 p2p->op_reg_class, p2p->op_channel); 312 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 313 goto fail; 314 } 315 p2p_dbg(p2p, "Selected operating channel - %d MHz", op_freq); 316 317 if (status == P2P_SC_SUCCESS) { 318 reg_class = p2p->op_reg_class; 319 channel = p2p->op_channel; 320 channels = &intersection; 321 } 322 } 323 324 fail: 325 if (go && status == P2P_SC_SUCCESS && !is_zero_ether_addr(group_bssid)) 326 bssid = group_bssid; 327 else 328 bssid = NULL; 329 resp = p2p_build_invitation_resp(p2p, dev, msg.dialog_token, status, 330 bssid, reg_class, channel, channels); 331 332 if (resp == NULL) 333 goto out; 334 335 if (rx_freq > 0) 336 freq = rx_freq; 337 else 338 freq = p2p_channel_to_freq(p2p->cfg->reg_class, 339 p2p->cfg->channel); 340 if (freq < 0) { 341 p2p_dbg(p2p, "Unknown regulatory class/channel"); 342 goto out; 343 } 344 345 /* 346 * Store copy of invitation data to be used when processing TX status 347 * callback for the Acton frame. 348 */ 349 os_memcpy(p2p->inv_sa, sa, ETH_ALEN); 350 if (msg.group_bssid) { 351 os_memcpy(p2p->inv_group_bssid, msg.group_bssid, ETH_ALEN); 352 p2p->inv_group_bssid_ptr = p2p->inv_group_bssid; 353 } else 354 p2p->inv_group_bssid_ptr = NULL; 355 if (msg.group_id_len - ETH_ALEN <= 32) { 356 os_memcpy(p2p->inv_ssid, msg.group_id + ETH_ALEN, 357 msg.group_id_len - ETH_ALEN); 358 p2p->inv_ssid_len = msg.group_id_len - ETH_ALEN; 359 } 360 os_memcpy(p2p->inv_go_dev_addr, msg.group_id, ETH_ALEN); 361 p2p->inv_status = status; 362 p2p->inv_op_freq = op_freq; 363 364 p2p->pending_action_state = P2P_PENDING_INVITATION_RESPONSE; 365 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, 366 p2p->cfg->dev_addr, 367 wpabuf_head(resp), wpabuf_len(resp), 200) < 0) { 368 p2p_dbg(p2p, "Failed to send Action frame"); 369 } 370 371 out: 372 wpabuf_free(resp); 373 p2p_parse_free(&msg); 374 } 375 376 377 void p2p_process_invitation_resp(struct p2p_data *p2p, const u8 *sa, 378 const u8 *data, size_t len) 379 { 380 struct p2p_device *dev; 381 struct p2p_message msg; 382 struct p2p_channels intersection, *channels = NULL; 383 384 p2p_dbg(p2p, "Received Invitation Response from " MACSTR, 385 MAC2STR(sa)); 386 387 dev = p2p_get_device(p2p, sa); 388 if (dev == NULL) { 389 p2p_dbg(p2p, "Ignore Invitation Response from unknown peer " 390 MACSTR, MAC2STR(sa)); 391 return; 392 } 393 394 if (dev != p2p->invite_peer) { 395 p2p_dbg(p2p, "Ignore unexpected Invitation Response from peer " 396 MACSTR, MAC2STR(sa)); 397 return; 398 } 399 400 if (p2p_parse(data, len, &msg)) 401 return; 402 403 if (!msg.status) { 404 p2p_dbg(p2p, "Mandatory Status attribute missing in Invitation Response from " 405 MACSTR, MAC2STR(sa)); 406 p2p_parse_free(&msg); 407 return; 408 } 409 410 if (!msg.channel_list) { 411 p2p_dbg(p2p, "Mandatory Channel List attribute missing in Invitation Response from " 412 MACSTR, MAC2STR(sa)); 413 #ifdef CONFIG_P2P_STRICT 414 p2p_parse_free(&msg); 415 return; 416 #endif /* CONFIG_P2P_STRICT */ 417 /* Try to survive without peer channel list */ 418 channels = &p2p->channels; 419 } else if (p2p_peer_channels_check(p2p, &p2p->channels, dev, 420 msg.channel_list, 421 msg.channel_list_len) < 0) { 422 p2p_dbg(p2p, "No common channels found"); 423 p2p_parse_free(&msg); 424 return; 425 } else { 426 p2p_channels_intersect(&p2p->channels, &dev->channels, 427 &intersection); 428 channels = &intersection; 429 } 430 431 if (p2p->cfg->invitation_result) 432 p2p->cfg->invitation_result(p2p->cfg->cb_ctx, *msg.status, 433 msg.group_bssid, channels, sa); 434 435 p2p_parse_free(&msg); 436 437 p2p_clear_timeout(p2p); 438 p2p_set_state(p2p, P2P_IDLE); 439 p2p->invite_peer = NULL; 440 } 441 442 443 int p2p_invite_send(struct p2p_data *p2p, struct p2p_device *dev, 444 const u8 *go_dev_addr) 445 { 446 struct wpabuf *req; 447 int freq; 448 449 freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq; 450 if (freq <= 0) { 451 p2p_dbg(p2p, "No Listen/Operating frequency known for the peer " 452 MACSTR " to send Invitation Request", 453 MAC2STR(dev->info.p2p_device_addr)); 454 return -1; 455 } 456 457 req = p2p_build_invitation_req(p2p, dev, go_dev_addr); 458 if (req == NULL) 459 return -1; 460 if (p2p->state != P2P_IDLE) 461 p2p_stop_listen_for_freq(p2p, freq); 462 p2p_dbg(p2p, "Sending Invitation Request"); 463 p2p_set_state(p2p, P2P_INVITE); 464 p2p->pending_action_state = P2P_PENDING_INVITATION_REQUEST; 465 p2p->invite_peer = dev; 466 dev->invitation_reqs++; 467 if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr, 468 p2p->cfg->dev_addr, dev->info.p2p_device_addr, 469 wpabuf_head(req), wpabuf_len(req), 200) < 0) { 470 p2p_dbg(p2p, "Failed to send Action frame"); 471 /* Use P2P find to recover and retry */ 472 p2p_set_timeout(p2p, 0, 0); 473 } 474 475 wpabuf_free(req); 476 477 return 0; 478 } 479 480 481 void p2p_invitation_req_cb(struct p2p_data *p2p, int success) 482 { 483 p2p_dbg(p2p, "Invitation Request TX callback: success=%d", success); 484 485 if (p2p->invite_peer == NULL) { 486 p2p_dbg(p2p, "No pending Invite"); 487 return; 488 } 489 490 /* 491 * Use P2P find, if needed, to find the other device from its listen 492 * channel. 493 */ 494 p2p_set_state(p2p, P2P_INVITE); 495 p2p_set_timeout(p2p, 0, success ? 350000 : 100000); 496 } 497 498 499 void p2p_invitation_resp_cb(struct p2p_data *p2p, int success) 500 { 501 p2p_dbg(p2p, "Invitation Response TX callback: success=%d", success); 502 p2p->cfg->send_action_done(p2p->cfg->cb_ctx); 503 504 if (!success) 505 p2p_dbg(p2p, "Assume Invitation Response was actually received by the peer even though Ack was not reported"); 506 507 if (p2p->cfg->invitation_received) { 508 p2p->cfg->invitation_received(p2p->cfg->cb_ctx, 509 p2p->inv_sa, 510 p2p->inv_group_bssid_ptr, 511 p2p->inv_ssid, p2p->inv_ssid_len, 512 p2p->inv_go_dev_addr, 513 p2p->inv_status, 514 p2p->inv_op_freq); 515 } 516 } 517 518 519 int p2p_invite(struct p2p_data *p2p, const u8 *peer, enum p2p_invite_role role, 520 const u8 *bssid, const u8 *ssid, size_t ssid_len, 521 unsigned int force_freq, const u8 *go_dev_addr, 522 int persistent_group, unsigned int pref_freq) 523 { 524 struct p2p_device *dev; 525 526 p2p_dbg(p2p, "Request to invite peer " MACSTR " role=%d persistent=%d " 527 "force_freq=%u", 528 MAC2STR(peer), role, persistent_group, force_freq); 529 if (bssid) 530 p2p_dbg(p2p, "Invitation for BSSID " MACSTR, MAC2STR(bssid)); 531 if (go_dev_addr) { 532 p2p_dbg(p2p, "Invitation for GO Device Address " MACSTR, 533 MAC2STR(go_dev_addr)); 534 os_memcpy(p2p->invite_go_dev_addr_buf, go_dev_addr, ETH_ALEN); 535 p2p->invite_go_dev_addr = p2p->invite_go_dev_addr_buf; 536 } else 537 p2p->invite_go_dev_addr = NULL; 538 wpa_hexdump_ascii(MSG_DEBUG, "Invitation for SSID", 539 ssid, ssid_len); 540 541 dev = p2p_get_device(p2p, peer); 542 if (dev == NULL || (dev->listen_freq <= 0 && dev->oper_freq <= 0)) { 543 p2p_dbg(p2p, "Cannot invite unknown P2P Device " MACSTR, 544 MAC2STR(peer)); 545 return -1; 546 } 547 548 if (p2p_prepare_channel(p2p, dev, force_freq, pref_freq) < 0) 549 return -1; 550 551 if (persistent_group && role == P2P_INVITE_ROLE_CLIENT && !force_freq && 552 !pref_freq) 553 dev->flags |= P2P_DEV_NO_PREF_CHAN; 554 else 555 dev->flags &= ~P2P_DEV_NO_PREF_CHAN; 556 557 if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) { 558 if (!(dev->info.dev_capab & 559 P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) { 560 p2p_dbg(p2p, "Cannot invite a P2P Device " MACSTR 561 " that is in a group and is not discoverable", 562 MAC2STR(peer)); 563 } 564 /* TODO: use device discoverability request through GO */ 565 } 566 567 dev->invitation_reqs = 0; 568 569 if (p2p->state != P2P_IDLE) 570 p2p_stop_find(p2p); 571 572 p2p->inv_role = role; 573 p2p->inv_bssid_set = bssid != NULL; 574 if (bssid) 575 os_memcpy(p2p->inv_bssid, bssid, ETH_ALEN); 576 os_memcpy(p2p->inv_ssid, ssid, ssid_len); 577 p2p->inv_ssid_len = ssid_len; 578 p2p->inv_persistent = persistent_group; 579 return p2p_invite_send(p2p, dev, go_dev_addr); 580 } 581
