p2p_go_neg.c revision fb79edc9df1f20461e90e478363d207348213d35
1/* 2 * Wi-Fi Direct - P2P Group Owner Negotiation 3 * Copyright (c) 2009-2010, 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 "wps/wps_defs.h" 14#include "p2p_i.h" 15#include "p2p.h" 16 17 18static int p2p_go_det(u8 own_intent, u8 peer_value) 19{ 20 u8 peer_intent = peer_value >> 1; 21 if (own_intent == peer_intent) { 22 if (own_intent == P2P_MAX_GO_INTENT) 23 return -1; /* both devices want to become GO */ 24 25 /* Use tie breaker bit to determine GO */ 26 return (peer_value & 0x01) ? 0 : 1; 27 } 28 29 return own_intent > peer_intent; 30} 31 32 33int p2p_peer_channels_check(struct p2p_data *p2p, struct p2p_channels *own, 34 struct p2p_device *dev, 35 const u8 *channel_list, size_t channel_list_len) 36{ 37 const u8 *pos, *end; 38 struct p2p_channels *ch; 39 size_t channels; 40 struct p2p_channels intersection; 41 42 ch = &dev->channels; 43 os_memset(ch, 0, sizeof(*ch)); 44 pos = channel_list; 45 end = channel_list + channel_list_len; 46 47 if (end - pos < 3) 48 return -1; 49 os_memcpy(dev->country, pos, 3); 50 wpa_hexdump_ascii(MSG_DEBUG, "P2P: Peer country", pos, 3); 51 if (pos[2] != 0x04 && os_memcmp(pos, p2p->cfg->country, 2) != 0) { 52 p2p_info(p2p, "Mismatching country (ours=%c%c peer's=%c%c)", 53 p2p->cfg->country[0], p2p->cfg->country[1], 54 pos[0], pos[1]); 55 return -1; 56 } 57 pos += 3; 58 59 while (pos + 2 < end) { 60 struct p2p_reg_class *cl = &ch->reg_class[ch->reg_classes]; 61 cl->reg_class = *pos++; 62 if (pos + 1 + pos[0] > end) { 63 p2p_info(p2p, "Invalid peer Channel List"); 64 return -1; 65 } 66 channels = *pos++; 67 cl->channels = channels > P2P_MAX_REG_CLASS_CHANNELS ? 68 P2P_MAX_REG_CLASS_CHANNELS : channels; 69 os_memcpy(cl->channel, pos, cl->channels); 70 pos += channels; 71 ch->reg_classes++; 72 if (ch->reg_classes == P2P_MAX_REG_CLASSES) 73 break; 74 } 75 76 p2p_channels_intersect(own, &dev->channels, &intersection); 77 p2p_dbg(p2p, "Own reg_classes %d peer reg_classes %d intersection reg_classes %d", 78 (int) own->reg_classes, 79 (int) dev->channels.reg_classes, 80 (int) intersection.reg_classes); 81 if (intersection.reg_classes == 0) { 82 p2p_info(p2p, "No common channels found"); 83 return -1; 84 } 85 return 0; 86} 87 88 89static int p2p_peer_channels(struct p2p_data *p2p, struct p2p_device *dev, 90 const u8 *channel_list, size_t channel_list_len) 91{ 92 return p2p_peer_channels_check(p2p, &p2p->channels, dev, 93 channel_list, channel_list_len); 94} 95 96 97u16 p2p_wps_method_pw_id(enum p2p_wps_method wps_method) 98{ 99 switch (wps_method) { 100 case WPS_PIN_DISPLAY: 101 return DEV_PW_REGISTRAR_SPECIFIED; 102 case WPS_PIN_KEYPAD: 103 return DEV_PW_USER_SPECIFIED; 104 case WPS_PBC: 105 return DEV_PW_PUSHBUTTON; 106 default: 107 return DEV_PW_DEFAULT; 108 } 109} 110 111 112static const char * p2p_wps_method_str(enum p2p_wps_method wps_method) 113{ 114 switch (wps_method) { 115 case WPS_PIN_DISPLAY: 116 return "Display"; 117 case WPS_PIN_KEYPAD: 118 return "Keypad"; 119 case WPS_PBC: 120 return "PBC"; 121 default: 122 return "??"; 123 } 124} 125 126 127static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p, 128 struct p2p_device *peer) 129{ 130 struct wpabuf *buf; 131 u8 *len; 132 u8 group_capab; 133 size_t extra = 0; 134 135#ifdef CONFIG_WIFI_DISPLAY 136 if (p2p->wfd_ie_go_neg) 137 extra = wpabuf_len(p2p->wfd_ie_go_neg); 138#endif /* CONFIG_WIFI_DISPLAY */ 139 140 buf = wpabuf_alloc(1000 + extra); 141 if (buf == NULL) 142 return NULL; 143 144 p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_REQ, peer->dialog_token); 145 146 len = p2p_buf_add_ie_hdr(buf); 147 group_capab = 0; 148 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) { 149 group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP; 150 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN) 151 group_capab |= P2P_GROUP_CAPAB_PERSISTENT_RECONN; 152 } 153 if (p2p->cross_connect) 154 group_capab |= P2P_GROUP_CAPAB_CROSS_CONN; 155 if (p2p->cfg->p2p_intra_bss) 156 group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST; 157 p2p_buf_add_capability(buf, p2p->dev_capab & 158 ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 159 group_capab); 160 p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | peer->tie_breaker); 161 p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout); 162 p2p_buf_add_listen_channel(buf, p2p->cfg->country, p2p->cfg->reg_class, 163 p2p->cfg->channel); 164 if (p2p->ext_listen_interval) 165 p2p_buf_add_ext_listen_timing(buf, p2p->ext_listen_period, 166 p2p->ext_listen_interval); 167 p2p_buf_add_intended_addr(buf, p2p->intended_addr); 168 p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels); 169 p2p_buf_add_device_info(buf, p2p, peer); 170 p2p_buf_add_operating_channel(buf, p2p->cfg->country, 171 p2p->op_reg_class, p2p->op_channel); 172 p2p_buf_update_ie_hdr(buf, len); 173 174 /* WPS IE with Device Password ID attribute */ 175 if (p2p_build_wps_ie(p2p, buf, p2p_wps_method_pw_id(peer->wps_method), 176 0) < 0) { 177 p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Request"); 178 wpabuf_free(buf); 179 return NULL; 180 } 181 182#ifdef CONFIG_WIFI_DISPLAY 183 if (p2p->wfd_ie_go_neg) 184 wpabuf_put_buf(buf, p2p->wfd_ie_go_neg); 185#endif /* CONFIG_WIFI_DISPLAY */ 186 187 return buf; 188} 189 190 191int p2p_connect_send(struct p2p_data *p2p, struct p2p_device *dev) 192{ 193 struct wpabuf *req; 194 int freq; 195 196 if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) { 197 u16 config_method; 198 p2p_dbg(p2p, "Use PD-before-GO-Neg workaround for " MACSTR, 199 MAC2STR(dev->info.p2p_device_addr)); 200 if (dev->wps_method == WPS_PIN_DISPLAY) 201 config_method = WPS_CONFIG_KEYPAD; 202 else if (dev->wps_method == WPS_PIN_KEYPAD) 203 config_method = WPS_CONFIG_DISPLAY; 204 else if (dev->wps_method == WPS_PBC) 205 config_method = WPS_CONFIG_PUSHBUTTON; 206 else 207 return -1; 208 return p2p_prov_disc_req(p2p, dev->info.p2p_device_addr, 209 config_method, 0, 0, 1); 210 } 211 212 freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq; 213 if (freq <= 0) { 214 p2p_dbg(p2p, "No Listen/Operating frequency known for the peer " 215 MACSTR " to send GO Negotiation Request", 216 MAC2STR(dev->info.p2p_device_addr)); 217 return -1; 218 } 219 220 req = p2p_build_go_neg_req(p2p, dev); 221 if (req == NULL) 222 return -1; 223 p2p_dbg(p2p, "Sending GO Negotiation Request"); 224 p2p_set_state(p2p, P2P_CONNECT); 225 p2p->pending_action_state = P2P_PENDING_GO_NEG_REQUEST; 226 p2p->go_neg_peer = dev; 227 dev->flags |= P2P_DEV_WAIT_GO_NEG_RESPONSE; 228 dev->connect_reqs++; 229 if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr, 230 p2p->cfg->dev_addr, dev->info.p2p_device_addr, 231 wpabuf_head(req), wpabuf_len(req), 500) < 0) { 232 p2p_dbg(p2p, "Failed to send Action frame"); 233 /* Use P2P find to recover and retry */ 234 p2p_set_timeout(p2p, 0, 0); 235 } else 236 dev->go_neg_req_sent++; 237 238 wpabuf_free(req); 239 240 return 0; 241} 242 243 244static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p, 245 struct p2p_device *peer, 246 u8 dialog_token, u8 status, 247 u8 tie_breaker) 248{ 249 struct wpabuf *buf; 250 u8 *len; 251 u8 group_capab; 252 size_t extra = 0; 253 254 p2p_dbg(p2p, "Building GO Negotiation Response"); 255 256#ifdef CONFIG_WIFI_DISPLAY 257 if (p2p->wfd_ie_go_neg) 258 extra = wpabuf_len(p2p->wfd_ie_go_neg); 259#endif /* CONFIG_WIFI_DISPLAY */ 260 261 buf = wpabuf_alloc(1000 + extra); 262 if (buf == NULL) 263 return NULL; 264 265 p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_RESP, dialog_token); 266 267 len = p2p_buf_add_ie_hdr(buf); 268 p2p_buf_add_status(buf, status); 269 group_capab = 0; 270 if (peer && peer->go_state == LOCAL_GO) { 271 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) { 272 group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP; 273 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN) 274 group_capab |= 275 P2P_GROUP_CAPAB_PERSISTENT_RECONN; 276 } 277 if (p2p->cross_connect) 278 group_capab |= P2P_GROUP_CAPAB_CROSS_CONN; 279 if (p2p->cfg->p2p_intra_bss) 280 group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST; 281 } 282 p2p_buf_add_capability(buf, p2p->dev_capab & 283 ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 284 group_capab); 285 p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | tie_breaker); 286 p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout); 287 if (peer && peer->go_state == REMOTE_GO) { 288 p2p_dbg(p2p, "Omit Operating Channel attribute"); 289 } else { 290 p2p_buf_add_operating_channel(buf, p2p->cfg->country, 291 p2p->op_reg_class, 292 p2p->op_channel); 293 } 294 p2p_buf_add_intended_addr(buf, p2p->intended_addr); 295 if (status || peer == NULL) { 296 p2p_buf_add_channel_list(buf, p2p->cfg->country, 297 &p2p->channels); 298 } else if (peer->go_state == REMOTE_GO) { 299 p2p_buf_add_channel_list(buf, p2p->cfg->country, 300 &p2p->channels); 301 } else { 302 struct p2p_channels res; 303 p2p_channels_intersect(&p2p->channels, &peer->channels, 304 &res); 305 p2p_buf_add_channel_list(buf, p2p->cfg->country, &res); 306 } 307 p2p_buf_add_device_info(buf, p2p, peer); 308 if (peer && peer->go_state == LOCAL_GO) { 309 p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid, 310 p2p->ssid_len); 311 } 312 p2p_buf_update_ie_hdr(buf, len); 313 314 /* WPS IE with Device Password ID attribute */ 315 if (p2p_build_wps_ie(p2p, buf, 316 p2p_wps_method_pw_id(peer ? peer->wps_method : 317 WPS_NOT_READY), 0) < 0) { 318 p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Response"); 319 wpabuf_free(buf); 320 return NULL; 321 } 322 323#ifdef CONFIG_WIFI_DISPLAY 324 if (p2p->wfd_ie_go_neg) 325 wpabuf_put_buf(buf, p2p->wfd_ie_go_neg); 326#endif /* CONFIG_WIFI_DISPLAY */ 327 328 329 return buf; 330} 331 332 333/** 334 * p2p_reselect_channel - Re-select operating channel based on peer information 335 * @p2p: P2P module context from p2p_init() 336 * @intersection: Support channel list intersection from local and peer 337 * 338 * This function is used to re-select the best channel after having received 339 * information from the peer to allow supported channel lists to be intersected. 340 * This can be used to improve initial channel selection done in 341 * p2p_prepare_channel() prior to the start of GO Negotiation. In addition, this 342 * can be used for Invitation case. 343 */ 344void p2p_reselect_channel(struct p2p_data *p2p, 345 struct p2p_channels *intersection) 346{ 347 struct p2p_reg_class *cl; 348 int freq; 349 u8 op_reg_class, op_channel; 350 unsigned int i; 351 const int op_classes_5ghz[] = { 124, 115, 0 }; 352 const int op_classes_ht40[] = { 126, 127, 116, 117, 0 }; 353 const int op_classes_vht[] = { 128, 0 }; 354 355 if (p2p->own_freq_preference > 0 && 356 p2p_freq_to_channel(p2p->own_freq_preference, 357 &op_reg_class, &op_channel) == 0 && 358 p2p_channels_includes(intersection, op_reg_class, op_channel)) { 359 p2p_dbg(p2p, "Pick own channel preference (reg_class %u channel %u) from intersection", 360 op_reg_class, op_channel); 361 p2p->op_reg_class = op_reg_class; 362 p2p->op_channel = op_channel; 363 return; 364 } 365 366 if (p2p->best_freq_overall > 0 && 367 p2p_freq_to_channel(p2p->best_freq_overall, 368 &op_reg_class, &op_channel) == 0 && 369 p2p_channels_includes(intersection, op_reg_class, op_channel)) { 370 p2p_dbg(p2p, "Pick best overall channel (reg_class %u channel %u) from intersection", 371 op_reg_class, op_channel); 372 p2p->op_reg_class = op_reg_class; 373 p2p->op_channel = op_channel; 374 return; 375 } 376 377 /* First, try to pick the best channel from another band */ 378 freq = p2p_channel_to_freq(p2p->op_reg_class, p2p->op_channel); 379 if (freq >= 2400 && freq < 2500 && p2p->best_freq_5 > 0 && 380 !p2p_channels_includes(intersection, p2p->op_reg_class, 381 p2p->op_channel) && 382 p2p_freq_to_channel(p2p->best_freq_5, 383 &op_reg_class, &op_channel) == 0 && 384 p2p_channels_includes(intersection, op_reg_class, op_channel)) { 385 p2p_dbg(p2p, "Pick best 5 GHz channel (reg_class %u channel %u) from intersection", 386 op_reg_class, op_channel); 387 p2p->op_reg_class = op_reg_class; 388 p2p->op_channel = op_channel; 389 return; 390 } 391 392 if (freq >= 4900 && freq < 6000 && p2p->best_freq_24 > 0 && 393 !p2p_channels_includes(intersection, p2p->op_reg_class, 394 p2p->op_channel) && 395 p2p_freq_to_channel(p2p->best_freq_24, 396 &op_reg_class, &op_channel) == 0 && 397 p2p_channels_includes(intersection, op_reg_class, op_channel)) { 398 p2p_dbg(p2p, "Pick best 2.4 GHz channel (reg_class %u channel %u) from intersection", 399 op_reg_class, op_channel); 400 p2p->op_reg_class = op_reg_class; 401 p2p->op_channel = op_channel; 402 return; 403 } 404 405 /* Select channel with highest preference if the peer supports it */ 406 for (i = 0; p2p->cfg->pref_chan && i < p2p->cfg->num_pref_chan; i++) { 407 if (p2p_channels_includes(intersection, 408 p2p->cfg->pref_chan[i].op_class, 409 p2p->cfg->pref_chan[i].chan)) { 410 p2p->op_reg_class = p2p->cfg->pref_chan[i].op_class; 411 p2p->op_channel = p2p->cfg->pref_chan[i].chan; 412 p2p_dbg(p2p, "Pick highest preferred channel (op_class %u channel %u) from intersection", 413 p2p->op_reg_class, p2p->op_channel); 414 return; 415 } 416 } 417 418 /* Try a channel where we might be able to use VHT */ 419 if (p2p_channel_select(intersection, op_classes_vht, 420 &p2p->op_reg_class, &p2p->op_channel) == 0) { 421 p2p_dbg(p2p, "Pick possible VHT channel (op_class %u channel %u) from intersection", 422 p2p->op_reg_class, p2p->op_channel); 423 return; 424 } 425 426 /* Try a channel where we might be able to use HT40 */ 427 if (p2p_channel_select(intersection, op_classes_ht40, 428 &p2p->op_reg_class, &p2p->op_channel) == 0) { 429 p2p_dbg(p2p, "Pick possible HT40 channel (op_class %u channel %u) from intersection", 430 p2p->op_reg_class, p2p->op_channel); 431 return; 432 } 433 434 /* Prefer a 5 GHz channel */ 435 if (p2p_channel_select(intersection, op_classes_5ghz, 436 &p2p->op_reg_class, &p2p->op_channel) == 0) { 437 p2p_dbg(p2p, "Pick possible 5 GHz channel (op_class %u channel %u) from intersection", 438 p2p->op_reg_class, p2p->op_channel); 439 return; 440 } 441 442 /* 443 * Try to see if the original channel is in the intersection. If 444 * so, no need to change anything, as it already contains some 445 * randomness. 446 */ 447 if (p2p_channels_includes(intersection, p2p->op_reg_class, 448 p2p->op_channel)) { 449 p2p_dbg(p2p, "Using original operating class and channel (op_class %u channel %u) from intersection", 450 p2p->op_reg_class, p2p->op_channel); 451 return; 452 } 453 454 /* 455 * Fall back to whatever is included in the channel intersection since 456 * no better options seems to be available. 457 */ 458 cl = &intersection->reg_class[0]; 459 p2p_dbg(p2p, "Pick another channel (reg_class %u channel %u) from intersection", 460 cl->reg_class, cl->channel[0]); 461 p2p->op_reg_class = cl->reg_class; 462 p2p->op_channel = cl->channel[0]; 463} 464 465 466static int p2p_go_select_channel(struct p2p_data *p2p, struct p2p_device *dev, 467 u8 *status) 468{ 469 struct p2p_channels tmp, intersection; 470 471 p2p_channels_dump(p2p, "own channels", &p2p->channels); 472 p2p_channels_dump(p2p, "peer channels", &dev->channels); 473 p2p_channels_intersect(&p2p->channels, &dev->channels, &tmp); 474 p2p_channels_dump(p2p, "intersection", &tmp); 475 p2p_channels_remove_freqs(&tmp, &p2p->no_go_freq); 476 p2p_channels_dump(p2p, "intersection after no-GO removal", &tmp); 477 p2p_channels_intersect(&tmp, &p2p->cfg->channels, &intersection); 478 p2p_channels_dump(p2p, "intersection with local channel list", 479 &intersection); 480 if (intersection.reg_classes == 0 || 481 intersection.reg_class[0].channels == 0) { 482 *status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 483 p2p_dbg(p2p, "No common channels found"); 484 return -1; 485 } 486 487 if (!p2p_channels_includes(&intersection, p2p->op_reg_class, 488 p2p->op_channel)) { 489 if (dev->flags & P2P_DEV_FORCE_FREQ) { 490 *status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 491 p2p_dbg(p2p, "Peer does not support the forced channel"); 492 return -1; 493 } 494 495 p2p_dbg(p2p, "Selected operating channel (op_class %u channel %u) not acceptable to the peer", 496 p2p->op_reg_class, p2p->op_channel); 497 p2p_reselect_channel(p2p, &intersection); 498 } else if (!(dev->flags & P2P_DEV_FORCE_FREQ) && 499 !p2p->cfg->cfg_op_channel) { 500 p2p_dbg(p2p, "Try to optimize channel selection with peer information received; previously selected op_class %u channel %u", 501 p2p->op_reg_class, p2p->op_channel); 502 p2p_reselect_channel(p2p, &intersection); 503 } 504 505 if (!p2p->ssid_set) { 506 p2p_build_ssid(p2p, p2p->ssid, &p2p->ssid_len); 507 p2p->ssid_set = 1; 508 } 509 510 return 0; 511} 512 513 514void p2p_process_go_neg_req(struct p2p_data *p2p, const u8 *sa, 515 const u8 *data, size_t len, int rx_freq) 516{ 517 struct p2p_device *dev = NULL; 518 struct wpabuf *resp; 519 struct p2p_message msg; 520 u8 status = P2P_SC_FAIL_INVALID_PARAMS; 521 int tie_breaker = 0; 522 int freq; 523 524 p2p_dbg(p2p, "Received GO Negotiation Request from " MACSTR "(freq=%d)", 525 MAC2STR(sa), rx_freq); 526 527 if (p2p_parse(data, len, &msg)) 528 return; 529 530 if (!msg.capability) { 531 p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Request"); 532#ifdef CONFIG_P2P_STRICT 533 goto fail; 534#endif /* CONFIG_P2P_STRICT */ 535 } 536 537 if (msg.go_intent) 538 tie_breaker = *msg.go_intent & 0x01; 539 else { 540 p2p_dbg(p2p, "Mandatory GO Intent attribute missing from GO Negotiation Request"); 541#ifdef CONFIG_P2P_STRICT 542 goto fail; 543#endif /* CONFIG_P2P_STRICT */ 544 } 545 546 if (!msg.config_timeout) { 547 p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Request"); 548#ifdef CONFIG_P2P_STRICT 549 goto fail; 550#endif /* CONFIG_P2P_STRICT */ 551 } 552 553 if (!msg.listen_channel) { 554 p2p_dbg(p2p, "No Listen Channel attribute received"); 555 goto fail; 556 } 557 if (!msg.operating_channel) { 558 p2p_dbg(p2p, "No Operating Channel attribute received"); 559 goto fail; 560 } 561 if (!msg.channel_list) { 562 p2p_dbg(p2p, "No Channel List attribute received"); 563 goto fail; 564 } 565 if (!msg.intended_addr) { 566 p2p_dbg(p2p, "No Intended P2P Interface Address attribute received"); 567 goto fail; 568 } 569 if (!msg.p2p_device_info) { 570 p2p_dbg(p2p, "No P2P Device Info attribute received"); 571 goto fail; 572 } 573 574 if (os_memcmp(msg.p2p_device_addr, sa, ETH_ALEN) != 0) { 575 p2p_dbg(p2p, "Unexpected GO Negotiation Request SA=" MACSTR 576 " != dev_addr=" MACSTR, 577 MAC2STR(sa), MAC2STR(msg.p2p_device_addr)); 578 goto fail; 579 } 580 581 dev = p2p_get_device(p2p, sa); 582 583 if (msg.status && *msg.status) { 584 p2p_dbg(p2p, "Unexpected Status attribute (%d) in GO Negotiation Request", 585 *msg.status); 586 goto fail; 587 } 588 589 if (dev == NULL) 590 dev = p2p_add_dev_from_go_neg_req(p2p, sa, &msg); 591 else if (dev->flags & P2P_DEV_PROBE_REQ_ONLY) 592 p2p_add_dev_info(p2p, sa, dev, &msg); 593 if (dev && dev->flags & P2P_DEV_USER_REJECTED) { 594 p2p_dbg(p2p, "User has rejected this peer"); 595 status = P2P_SC_FAIL_REJECTED_BY_USER; 596 } else if (dev == NULL || dev->wps_method == WPS_NOT_READY) { 597 p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR, 598 MAC2STR(sa)); 599 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; 600 p2p->cfg->go_neg_req_rx(p2p->cfg->cb_ctx, sa, 601 msg.dev_password_id); 602 } else if (p2p->go_neg_peer && p2p->go_neg_peer != dev) { 603 p2p_dbg(p2p, "Already in Group Formation with another peer"); 604 status = P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE; 605 } else { 606 int go; 607 608 if (!p2p->go_neg_peer) { 609 p2p_dbg(p2p, "Starting GO Negotiation with previously authorized peer"); 610 if (!(dev->flags & P2P_DEV_FORCE_FREQ)) { 611 p2p_dbg(p2p, "Use default channel settings"); 612 p2p->op_reg_class = p2p->cfg->op_reg_class; 613 p2p->op_channel = p2p->cfg->op_channel; 614 os_memcpy(&p2p->channels, &p2p->cfg->channels, 615 sizeof(struct p2p_channels)); 616 } else { 617 p2p_dbg(p2p, "Use previously configured forced channel settings"); 618 } 619 } 620 621 dev->flags &= ~P2P_DEV_NOT_YET_READY; 622 623 if (!msg.go_intent) { 624 p2p_dbg(p2p, "No GO Intent attribute received"); 625 goto fail; 626 } 627 if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) { 628 p2p_dbg(p2p, "Invalid GO Intent value (%u) received", 629 *msg.go_intent >> 1); 630 goto fail; 631 } 632 633 if (dev->go_neg_req_sent && 634 os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) > 0) { 635 p2p_dbg(p2p, "Do not reply since peer has higher address and GO Neg Request already sent"); 636 p2p_parse_free(&msg); 637 return; 638 } 639 640 go = p2p_go_det(p2p->go_intent, *msg.go_intent); 641 if (go < 0) { 642 p2p_dbg(p2p, "Incompatible GO Intent"); 643 status = P2P_SC_FAIL_BOTH_GO_INTENT_15; 644 goto fail; 645 } 646 647 if (p2p_peer_channels(p2p, dev, msg.channel_list, 648 msg.channel_list_len) < 0) { 649 p2p_dbg(p2p, "No common channels found"); 650 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 651 goto fail; 652 } 653 654 switch (msg.dev_password_id) { 655 case DEV_PW_REGISTRAR_SPECIFIED: 656 p2p_dbg(p2p, "PIN from peer Display"); 657 if (dev->wps_method != WPS_PIN_KEYPAD) { 658 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 659 p2p_wps_method_str(dev->wps_method)); 660 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 661 goto fail; 662 } 663 break; 664 case DEV_PW_USER_SPECIFIED: 665 p2p_dbg(p2p, "Peer entered PIN on Keypad"); 666 if (dev->wps_method != WPS_PIN_DISPLAY) { 667 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 668 p2p_wps_method_str(dev->wps_method)); 669 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 670 goto fail; 671 } 672 break; 673 case DEV_PW_PUSHBUTTON: 674 p2p_dbg(p2p, "Peer using pushbutton"); 675 if (dev->wps_method != WPS_PBC) { 676 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 677 p2p_wps_method_str(dev->wps_method)); 678 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 679 goto fail; 680 } 681 break; 682 default: 683 p2p_dbg(p2p, "Unsupported Device Password ID %d", 684 msg.dev_password_id); 685 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 686 goto fail; 687 } 688 689 if (go && p2p_go_select_channel(p2p, dev, &status) < 0) 690 goto fail; 691 692 dev->go_state = go ? LOCAL_GO : REMOTE_GO; 693 dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3], 694 msg.operating_channel[4]); 695 p2p_dbg(p2p, "Peer operating channel preference: %d MHz", 696 dev->oper_freq); 697 698 if (msg.config_timeout) { 699 dev->go_timeout = msg.config_timeout[0]; 700 dev->client_timeout = msg.config_timeout[1]; 701 } 702 703 p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa)); 704 if (p2p->state != P2P_IDLE) 705 p2p_stop_find_for_freq(p2p, rx_freq); 706 p2p_set_state(p2p, P2P_GO_NEG); 707 p2p_clear_timeout(p2p); 708 dev->dialog_token = msg.dialog_token; 709 os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN); 710 p2p->go_neg_peer = dev; 711 status = P2P_SC_SUCCESS; 712 } 713 714fail: 715 if (dev) 716 dev->status = status; 717 resp = p2p_build_go_neg_resp(p2p, dev, msg.dialog_token, status, 718 !tie_breaker); 719 p2p_parse_free(&msg); 720 if (resp == NULL) 721 return; 722 p2p_dbg(p2p, "Sending GO Negotiation Response"); 723 if (rx_freq > 0) 724 freq = rx_freq; 725 else 726 freq = p2p_channel_to_freq(p2p->cfg->reg_class, 727 p2p->cfg->channel); 728 if (freq < 0) { 729 p2p_dbg(p2p, "Unknown regulatory class/channel"); 730 wpabuf_free(resp); 731 return; 732 } 733 if (status == P2P_SC_SUCCESS) { 734 p2p->pending_action_state = P2P_PENDING_GO_NEG_RESPONSE; 735 dev->flags |= P2P_DEV_WAIT_GO_NEG_CONFIRM; 736 if (os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) < 0) { 737 /* 738 * Peer has smaller address, so the GO Negotiation 739 * Response from us is expected to complete 740 * negotiation. Ignore a GO Negotiation Response from 741 * the peer if it happens to be received after this 742 * point due to a race condition in GO Negotiation 743 * Request transmission and processing. 744 */ 745 dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE; 746 } 747 } else 748 p2p->pending_action_state = 749 P2P_PENDING_GO_NEG_RESPONSE_FAILURE; 750 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, 751 p2p->cfg->dev_addr, 752 wpabuf_head(resp), wpabuf_len(resp), 500) < 0) { 753 p2p_dbg(p2p, "Failed to send Action frame"); 754 } 755 756 wpabuf_free(resp); 757} 758 759 760static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p, 761 struct p2p_device *peer, 762 u8 dialog_token, u8 status, 763 const u8 *resp_chan, int go) 764{ 765 struct wpabuf *buf; 766 u8 *len; 767 struct p2p_channels res; 768 u8 group_capab; 769 size_t extra = 0; 770 771 p2p_dbg(p2p, "Building GO Negotiation Confirm"); 772 773#ifdef CONFIG_WIFI_DISPLAY 774 if (p2p->wfd_ie_go_neg) 775 extra = wpabuf_len(p2p->wfd_ie_go_neg); 776#endif /* CONFIG_WIFI_DISPLAY */ 777 778 buf = wpabuf_alloc(1000 + extra); 779 if (buf == NULL) 780 return NULL; 781 782 p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_CONF, dialog_token); 783 784 len = p2p_buf_add_ie_hdr(buf); 785 p2p_buf_add_status(buf, status); 786 group_capab = 0; 787 if (peer->go_state == LOCAL_GO) { 788 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) { 789 group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP; 790 if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN) 791 group_capab |= 792 P2P_GROUP_CAPAB_PERSISTENT_RECONN; 793 } 794 if (p2p->cross_connect) 795 group_capab |= P2P_GROUP_CAPAB_CROSS_CONN; 796 if (p2p->cfg->p2p_intra_bss) 797 group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST; 798 } 799 p2p_buf_add_capability(buf, p2p->dev_capab & 800 ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 801 group_capab); 802 if (go || resp_chan == NULL) 803 p2p_buf_add_operating_channel(buf, p2p->cfg->country, 804 p2p->op_reg_class, 805 p2p->op_channel); 806 else 807 p2p_buf_add_operating_channel(buf, (const char *) resp_chan, 808 resp_chan[3], resp_chan[4]); 809 p2p_channels_intersect(&p2p->channels, &peer->channels, &res); 810 p2p_buf_add_channel_list(buf, p2p->cfg->country, &res); 811 if (go) { 812 p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid, 813 p2p->ssid_len); 814 } 815 p2p_buf_update_ie_hdr(buf, len); 816 817#ifdef CONFIG_WIFI_DISPLAY 818 if (p2p->wfd_ie_go_neg) 819 wpabuf_put_buf(buf, p2p->wfd_ie_go_neg); 820#endif /* CONFIG_WIFI_DISPLAY */ 821 822 return buf; 823} 824 825 826void p2p_process_go_neg_resp(struct p2p_data *p2p, const u8 *sa, 827 const u8 *data, size_t len, int rx_freq) 828{ 829 struct p2p_device *dev; 830 struct wpabuf *conf; 831 int go = -1; 832 struct p2p_message msg; 833 u8 status = P2P_SC_SUCCESS; 834 int freq; 835 836 p2p_dbg(p2p, "Received GO Negotiation Response from " MACSTR 837 " (freq=%d)", MAC2STR(sa), rx_freq); 838 dev = p2p_get_device(p2p, sa); 839 if (dev == NULL || dev->wps_method == WPS_NOT_READY || 840 dev != p2p->go_neg_peer) { 841 p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR, 842 MAC2STR(sa)); 843 return; 844 } 845 846 if (p2p_parse(data, len, &msg)) 847 return; 848 849 if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_RESPONSE)) { 850 p2p_dbg(p2p, "Was not expecting GO Negotiation Response - ignore"); 851 p2p_parse_free(&msg); 852 return; 853 } 854 dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE; 855 856 if (msg.dialog_token != dev->dialog_token) { 857 p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)", 858 msg.dialog_token, dev->dialog_token); 859 p2p_parse_free(&msg); 860 return; 861 } 862 863 if (!msg.status) { 864 p2p_dbg(p2p, "No Status attribute received"); 865 status = P2P_SC_FAIL_INVALID_PARAMS; 866 goto fail; 867 } 868 if (*msg.status) { 869 p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status); 870 dev->go_neg_req_sent = 0; 871 if (*msg.status == P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE) { 872 p2p_dbg(p2p, "Wait for the peer to become ready for GO Negotiation"); 873 dev->flags |= P2P_DEV_NOT_YET_READY; 874 dev->wait_count = 0; 875 p2p_set_state(p2p, P2P_WAIT_PEER_IDLE); 876 p2p_set_timeout(p2p, 0, 0); 877 } else { 878 p2p_dbg(p2p, "Stop GO Negotiation attempt"); 879 p2p_go_neg_failed(p2p, dev, *msg.status); 880 } 881 p2p->cfg->send_action_done(p2p->cfg->cb_ctx); 882 p2p_parse_free(&msg); 883 return; 884 } 885 886 if (!msg.capability) { 887 p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Response"); 888#ifdef CONFIG_P2P_STRICT 889 status = P2P_SC_FAIL_INVALID_PARAMS; 890 goto fail; 891#endif /* CONFIG_P2P_STRICT */ 892 } 893 894 if (!msg.p2p_device_info) { 895 p2p_dbg(p2p, "Mandatory P2P Device Info attribute missing from GO Negotiation Response"); 896#ifdef CONFIG_P2P_STRICT 897 status = P2P_SC_FAIL_INVALID_PARAMS; 898 goto fail; 899#endif /* CONFIG_P2P_STRICT */ 900 } 901 902 if (!msg.intended_addr) { 903 p2p_dbg(p2p, "No Intended P2P Interface Address attribute received"); 904 status = P2P_SC_FAIL_INVALID_PARAMS; 905 goto fail; 906 } 907 908 if (!msg.go_intent) { 909 p2p_dbg(p2p, "No GO Intent attribute received"); 910 status = P2P_SC_FAIL_INVALID_PARAMS; 911 goto fail; 912 } 913 if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) { 914 p2p_dbg(p2p, "Invalid GO Intent value (%u) received", 915 *msg.go_intent >> 1); 916 status = P2P_SC_FAIL_INVALID_PARAMS; 917 goto fail; 918 } 919 920 go = p2p_go_det(p2p->go_intent, *msg.go_intent); 921 if (go < 0) { 922 p2p_dbg(p2p, "Incompatible GO Intent"); 923 status = P2P_SC_FAIL_INCOMPATIBLE_PARAMS; 924 goto fail; 925 } 926 927 if (!go && msg.group_id) { 928 /* Store SSID for Provisioning step */ 929 p2p->ssid_len = msg.group_id_len - ETH_ALEN; 930 os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len); 931 } else if (!go) { 932 p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Response"); 933 p2p->ssid_len = 0; 934 status = P2P_SC_FAIL_INVALID_PARAMS; 935 goto fail; 936 } 937 938 if (!msg.config_timeout) { 939 p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Response"); 940#ifdef CONFIG_P2P_STRICT 941 status = P2P_SC_FAIL_INVALID_PARAMS; 942 goto fail; 943#endif /* CONFIG_P2P_STRICT */ 944 } else { 945 dev->go_timeout = msg.config_timeout[0]; 946 dev->client_timeout = msg.config_timeout[1]; 947 } 948 949 if (!msg.operating_channel && !go) { 950 /* 951 * Note: P2P Client may omit Operating Channel attribute to 952 * indicate it does not have a preference. 953 */ 954 p2p_dbg(p2p, "No Operating Channel attribute received"); 955 status = P2P_SC_FAIL_INVALID_PARAMS; 956 goto fail; 957 } 958 if (!msg.channel_list) { 959 p2p_dbg(p2p, "No Channel List attribute received"); 960 status = P2P_SC_FAIL_INVALID_PARAMS; 961 goto fail; 962 } 963 964 if (p2p_peer_channels(p2p, dev, msg.channel_list, 965 msg.channel_list_len) < 0) { 966 p2p_dbg(p2p, "No common channels found"); 967 status = P2P_SC_FAIL_NO_COMMON_CHANNELS; 968 goto fail; 969 } 970 971 if (msg.operating_channel) { 972 dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3], 973 msg.operating_channel[4]); 974 p2p_dbg(p2p, "Peer operating channel preference: %d MHz", 975 dev->oper_freq); 976 } else 977 dev->oper_freq = 0; 978 979 switch (msg.dev_password_id) { 980 case DEV_PW_REGISTRAR_SPECIFIED: 981 p2p_dbg(p2p, "PIN from peer Display"); 982 if (dev->wps_method != WPS_PIN_KEYPAD) { 983 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 984 p2p_wps_method_str(dev->wps_method)); 985 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 986 goto fail; 987 } 988 break; 989 case DEV_PW_USER_SPECIFIED: 990 p2p_dbg(p2p, "Peer entered PIN on Keypad"); 991 if (dev->wps_method != WPS_PIN_DISPLAY) { 992 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 993 p2p_wps_method_str(dev->wps_method)); 994 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 995 goto fail; 996 } 997 break; 998 case DEV_PW_PUSHBUTTON: 999 p2p_dbg(p2p, "Peer using pushbutton"); 1000 if (dev->wps_method != WPS_PBC) { 1001 p2p_dbg(p2p, "We have wps_method=%s -> incompatible", 1002 p2p_wps_method_str(dev->wps_method)); 1003 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 1004 goto fail; 1005 } 1006 break; 1007 default: 1008 p2p_dbg(p2p, "Unsupported Device Password ID %d", 1009 msg.dev_password_id); 1010 status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD; 1011 goto fail; 1012 } 1013 1014 if (go && p2p_go_select_channel(p2p, dev, &status) < 0) 1015 goto fail; 1016 1017 p2p_set_state(p2p, P2P_GO_NEG); 1018 p2p_clear_timeout(p2p); 1019 1020 p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa)); 1021 os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN); 1022 1023fail: 1024 conf = p2p_build_go_neg_conf(p2p, dev, msg.dialog_token, status, 1025 msg.operating_channel, go); 1026 p2p_parse_free(&msg); 1027 if (conf == NULL) 1028 return; 1029 p2p_dbg(p2p, "Sending GO Negotiation Confirm"); 1030 if (status == P2P_SC_SUCCESS) { 1031 p2p->pending_action_state = P2P_PENDING_GO_NEG_CONFIRM; 1032 dev->go_state = go ? LOCAL_GO : REMOTE_GO; 1033 } else 1034 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 1035 if (rx_freq > 0) 1036 freq = rx_freq; 1037 else 1038 freq = dev->listen_freq; 1039 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, sa, 1040 wpabuf_head(conf), wpabuf_len(conf), 0) < 0) { 1041 p2p_dbg(p2p, "Failed to send Action frame"); 1042 p2p_go_neg_failed(p2p, dev, -1); 1043 p2p->cfg->send_action_done(p2p->cfg->cb_ctx); 1044 } 1045 wpabuf_free(conf); 1046 if (status != P2P_SC_SUCCESS) { 1047 p2p_dbg(p2p, "GO Negotiation failed"); 1048 p2p_go_neg_failed(p2p, dev, status); 1049 } 1050} 1051 1052 1053void p2p_process_go_neg_conf(struct p2p_data *p2p, const u8 *sa, 1054 const u8 *data, size_t len) 1055{ 1056 struct p2p_device *dev; 1057 struct p2p_message msg; 1058 1059 p2p_dbg(p2p, "Received GO Negotiation Confirm from " MACSTR, 1060 MAC2STR(sa)); 1061 dev = p2p_get_device(p2p, sa); 1062 if (dev == NULL || dev->wps_method == WPS_NOT_READY || 1063 dev != p2p->go_neg_peer) { 1064 p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR, 1065 MAC2STR(sa)); 1066 return; 1067 } 1068 1069 if (p2p->pending_action_state == P2P_PENDING_GO_NEG_RESPONSE) { 1070 p2p_dbg(p2p, "Stopped waiting for TX status on GO Negotiation Response since we already received Confirmation"); 1071 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 1072 } 1073 1074 if (p2p_parse(data, len, &msg)) 1075 return; 1076 1077 if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_CONFIRM)) { 1078 p2p_dbg(p2p, "Was not expecting GO Negotiation Confirm - ignore"); 1079 return; 1080 } 1081 dev->flags &= ~P2P_DEV_WAIT_GO_NEG_CONFIRM; 1082 1083 if (msg.dialog_token != dev->dialog_token) { 1084 p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)", 1085 msg.dialog_token, dev->dialog_token); 1086 p2p_parse_free(&msg); 1087 return; 1088 } 1089 1090 if (!msg.status) { 1091 p2p_dbg(p2p, "No Status attribute received"); 1092 p2p_parse_free(&msg); 1093 return; 1094 } 1095 if (*msg.status) { 1096 p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status); 1097 p2p_go_neg_failed(p2p, dev, *msg.status); 1098 p2p_parse_free(&msg); 1099 return; 1100 } 1101 1102 if (dev->go_state == REMOTE_GO && msg.group_id) { 1103 /* Store SSID for Provisioning step */ 1104 p2p->ssid_len = msg.group_id_len - ETH_ALEN; 1105 os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len); 1106 } else if (dev->go_state == REMOTE_GO) { 1107 p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Confirmation"); 1108 p2p->ssid_len = 0; 1109 p2p_go_neg_failed(p2p, dev, P2P_SC_FAIL_INVALID_PARAMS); 1110 p2p_parse_free(&msg); 1111 return; 1112 } 1113 1114 if (!msg.operating_channel) { 1115 p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation"); 1116#ifdef CONFIG_P2P_STRICT 1117 p2p_parse_free(&msg); 1118 return; 1119#endif /* CONFIG_P2P_STRICT */ 1120 } else if (dev->go_state == REMOTE_GO) { 1121 int oper_freq = p2p_channel_to_freq(msg.operating_channel[3], 1122 msg.operating_channel[4]); 1123 if (oper_freq != dev->oper_freq) { 1124 p2p_dbg(p2p, "Updated peer (GO) operating channel preference from %d MHz to %d MHz", 1125 dev->oper_freq, oper_freq); 1126 dev->oper_freq = oper_freq; 1127 } 1128 } 1129 1130 if (!msg.channel_list) { 1131 p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation"); 1132#ifdef CONFIG_P2P_STRICT 1133 p2p_parse_free(&msg); 1134 return; 1135#endif /* CONFIG_P2P_STRICT */ 1136 } 1137 1138 p2p_parse_free(&msg); 1139 1140 if (dev->go_state == UNKNOWN_GO) { 1141 /* 1142 * This should not happen since GO negotiation has already 1143 * been completed. 1144 */ 1145 p2p_dbg(p2p, "Unexpected GO Neg state - do not know which end becomes GO"); 1146 return; 1147 } 1148 1149 /* 1150 * The peer could have missed our ctrl::ack frame for GO Negotiation 1151 * Confirm and continue retransmitting the frame. To reduce the 1152 * likelihood of the peer not getting successful TX status for the 1153 * GO Negotiation Confirm frame, wait a short time here before starting 1154 * the group so that we will remain on the current channel to 1155 * acknowledge any possible retransmission from the peer. 1156 */ 1157 p2p_dbg(p2p, "20 ms wait on current channel before starting group"); 1158 os_sleep(0, 20000); 1159 1160 p2p_go_complete(p2p, dev); 1161} 1162