1 /* 2 * Wi-Fi Direct - P2P provision discovery 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 18 /* 19 * Number of retries to attempt for provision discovery requests 20 * in case the peer is not listening. 21 */ 22 #define MAX_PROV_DISC_REQ_RETRIES 120 23 24 25 static void p2p_build_wps_ie_config_methods(struct wpabuf *buf, 26 u16 config_methods) 27 { 28 u8 *len; 29 wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC); 30 len = wpabuf_put(buf, 1); 31 wpabuf_put_be32(buf, WPS_DEV_OUI_WFA); 32 33 /* Config Methods */ 34 wpabuf_put_be16(buf, ATTR_CONFIG_METHODS); 35 wpabuf_put_be16(buf, 2); 36 wpabuf_put_be16(buf, config_methods); 37 38 p2p_buf_update_ie_hdr(buf, len); 39 } 40 41 42 static struct wpabuf * p2p_build_prov_disc_req(struct p2p_data *p2p, 43 u8 dialog_token, 44 u16 config_methods, 45 struct p2p_device *go) 46 { 47 struct wpabuf *buf; 48 u8 *len; 49 size_t extra = 0; 50 51 #ifdef CONFIG_WIFI_DISPLAY 52 if (p2p->wfd_ie_prov_disc_req) 53 extra = wpabuf_len(p2p->wfd_ie_prov_disc_req); 54 #endif /* CONFIG_WIFI_DISPLAY */ 55 56 buf = wpabuf_alloc(1000 + extra); 57 if (buf == NULL) 58 return NULL; 59 60 p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_REQ, dialog_token); 61 62 len = p2p_buf_add_ie_hdr(buf); 63 p2p_buf_add_capability(buf, p2p->dev_capab & 64 ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 0); 65 p2p_buf_add_device_info(buf, p2p, NULL); 66 if (go) { 67 p2p_buf_add_group_id(buf, go->info.p2p_device_addr, 68 go->oper_ssid, go->oper_ssid_len); 69 } 70 p2p_buf_update_ie_hdr(buf, len); 71 72 /* WPS IE with Config Methods attribute */ 73 p2p_build_wps_ie_config_methods(buf, config_methods); 74 75 #ifdef CONFIG_WIFI_DISPLAY 76 if (p2p->wfd_ie_prov_disc_req) 77 wpabuf_put_buf(buf, p2p->wfd_ie_prov_disc_req); 78 #endif /* CONFIG_WIFI_DISPLAY */ 79 80 return buf; 81 } 82 83 84 static struct wpabuf * p2p_build_prov_disc_resp(struct p2p_data *p2p, 85 u8 dialog_token, 86 u16 config_methods, 87 const u8 *group_id, 88 size_t group_id_len) 89 { 90 struct wpabuf *buf; 91 size_t extra = 0; 92 93 #ifdef CONFIG_WIFI_DISPLAY 94 struct wpabuf *wfd_ie = p2p->wfd_ie_prov_disc_resp; 95 if (wfd_ie && group_id) { 96 size_t i; 97 for (i = 0; i < p2p->num_groups; i++) { 98 struct p2p_group *g = p2p->groups[i]; 99 struct wpabuf *ie; 100 if (!p2p_group_is_group_id_match(g, group_id, 101 group_id_len)) 102 continue; 103 ie = p2p_group_get_wfd_ie(g); 104 if (ie) { 105 wfd_ie = ie; 106 break; 107 } 108 } 109 } 110 if (wfd_ie) 111 extra = wpabuf_len(wfd_ie); 112 #endif /* CONFIG_WIFI_DISPLAY */ 113 114 buf = wpabuf_alloc(100 + extra); 115 if (buf == NULL) 116 return NULL; 117 118 p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_RESP, dialog_token); 119 120 /* WPS IE with Config Methods attribute */ 121 p2p_build_wps_ie_config_methods(buf, config_methods); 122 123 #ifdef CONFIG_WIFI_DISPLAY 124 if (wfd_ie) 125 wpabuf_put_buf(buf, wfd_ie); 126 #endif /* CONFIG_WIFI_DISPLAY */ 127 128 return buf; 129 } 130 131 132 void p2p_process_prov_disc_req(struct p2p_data *p2p, const u8 *sa, 133 const u8 *data, size_t len, int rx_freq) 134 { 135 struct p2p_message msg; 136 struct p2p_device *dev; 137 int freq; 138 int reject = 1; 139 struct wpabuf *resp; 140 141 if (p2p_parse(data, len, &msg)) 142 return; 143 144 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 145 "P2P: Received Provision Discovery Request from " MACSTR 146 " with config methods 0x%x (freq=%d)", 147 MAC2STR(sa), msg.wps_config_methods, rx_freq); 148 149 dev = p2p_get_device(p2p, sa); 150 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { 151 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 152 "P2P: Provision Discovery Request from " 153 "unknown peer " MACSTR, MAC2STR(sa)); 154 155 if (p2p_add_device(p2p, sa, rx_freq, 0, 0, data + 1, len - 1, 156 0)) { 157 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 158 "P2P: Provision Discovery Request add device " 159 "failed " MACSTR, MAC2STR(sa)); 160 } 161 } else if (msg.wfd_subelems) { 162 wpabuf_free(dev->info.wfd_subelems); 163 dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems); 164 } 165 166 if (!(msg.wps_config_methods & 167 (WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD | 168 WPS_CONFIG_PUSHBUTTON))) { 169 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Unsupported " 170 "Config Methods in Provision Discovery Request"); 171 goto out; 172 } 173 174 if (msg.group_id) { 175 size_t i; 176 for (i = 0; i < p2p->num_groups; i++) { 177 if (p2p_group_is_group_id_match(p2p->groups[i], 178 msg.group_id, 179 msg.group_id_len)) 180 break; 181 } 182 if (i == p2p->num_groups) { 183 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: PD " 184 "request for unknown P2P Group ID - reject"); 185 goto out; 186 } 187 } 188 189 if (dev) 190 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY | 191 P2P_DEV_PD_PEER_KEYPAD); 192 if (msg.wps_config_methods & WPS_CONFIG_DISPLAY) { 193 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR 194 " requested us to show a PIN on display", MAC2STR(sa)); 195 if (dev) 196 dev->flags |= P2P_DEV_PD_PEER_KEYPAD; 197 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) { 198 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR 199 " requested us to write its PIN using keypad", 200 MAC2STR(sa)); 201 if (dev) 202 dev->flags |= P2P_DEV_PD_PEER_DISPLAY; 203 } 204 205 reject = 0; 206 207 out: 208 resp = p2p_build_prov_disc_resp(p2p, msg.dialog_token, 209 reject ? 0 : msg.wps_config_methods, 210 msg.group_id, msg.group_id_len); 211 if (resp == NULL) { 212 p2p_parse_free(&msg); 213 return; 214 } 215 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 216 "P2P: Sending Provision Discovery Response"); 217 if (rx_freq > 0) 218 freq = rx_freq; 219 else 220 freq = p2p_channel_to_freq(p2p->cfg->country, 221 p2p->cfg->reg_class, 222 p2p->cfg->channel); 223 if (freq < 0) { 224 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 225 "P2P: Unknown regulatory class/channel"); 226 wpabuf_free(resp); 227 p2p_parse_free(&msg); 228 return; 229 } 230 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 231 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, 232 p2p->cfg->dev_addr, 233 wpabuf_head(resp), wpabuf_len(resp), 200) < 0) { 234 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 235 "P2P: Failed to send Action frame"); 236 } 237 238 wpabuf_free(resp); 239 240 if (!reject && p2p->cfg->prov_disc_req) { 241 const u8 *dev_addr = sa; 242 if (msg.p2p_device_addr) 243 dev_addr = msg.p2p_device_addr; 244 p2p->cfg->prov_disc_req(p2p->cfg->cb_ctx, sa, 245 msg.wps_config_methods, 246 dev_addr, msg.pri_dev_type, 247 msg.device_name, msg.config_methods, 248 msg.capability ? msg.capability[0] : 0, 249 msg.capability ? msg.capability[1] : 250 0, 251 msg.group_id, msg.group_id_len); 252 } 253 p2p_parse_free(&msg); 254 } 255 256 257 void p2p_process_prov_disc_resp(struct p2p_data *p2p, const u8 *sa, 258 const u8 *data, size_t len) 259 { 260 struct p2p_message msg; 261 struct p2p_device *dev; 262 u16 report_config_methods = 0; 263 int success = 0; 264 265 if (p2p_parse(data, len, &msg)) 266 return; 267 268 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 269 "P2P: Received Provision Discovery Response from " MACSTR 270 " with config methods 0x%x", 271 MAC2STR(sa), msg.wps_config_methods); 272 273 dev = p2p_get_device(p2p, sa); 274 if (dev == NULL || !dev->req_config_methods) { 275 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 276 "P2P: Ignore Provision Discovery Response from " 277 MACSTR " with no pending request", MAC2STR(sa)); 278 p2p_parse_free(&msg); 279 return; 280 } 281 282 if (dev->dialog_token != msg.dialog_token) { 283 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 284 "P2P: Ignore Provision Discovery Response with " 285 "unexpected Dialog Token %u (expected %u)", 286 msg.dialog_token, dev->dialog_token); 287 p2p_parse_free(&msg); 288 return; 289 } 290 291 if (p2p->pending_action_state == P2P_PENDING_PD) { 292 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN); 293 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 294 } 295 296 /* 297 * If the response is from the peer to whom a user initiated request 298 * was sent earlier, we reset that state info here. 299 */ 300 if (p2p->user_initiated_pd && 301 os_memcmp(p2p->pending_pd_devaddr, sa, ETH_ALEN) == 0) 302 p2p_reset_pending_pd(p2p); 303 304 if (msg.wps_config_methods != dev->req_config_methods) { 305 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer rejected " 306 "our Provision Discovery Request"); 307 if (p2p->cfg->prov_disc_fail) 308 p2p->cfg->prov_disc_fail(p2p->cfg->cb_ctx, sa, 309 P2P_PROV_DISC_REJECTED); 310 p2p_parse_free(&msg); 311 goto out; 312 } 313 314 report_config_methods = dev->req_config_methods; 315 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY | 316 P2P_DEV_PD_PEER_KEYPAD); 317 if (dev->req_config_methods & WPS_CONFIG_DISPLAY) { 318 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR 319 " accepted to show a PIN on display", MAC2STR(sa)); 320 dev->flags |= P2P_DEV_PD_PEER_DISPLAY; 321 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) { 322 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR 323 " accepted to write our PIN using keypad", 324 MAC2STR(sa)); 325 dev->flags |= P2P_DEV_PD_PEER_KEYPAD; 326 } 327 328 /* Store the provisioning info */ 329 dev->wps_prov_info = msg.wps_config_methods; 330 331 p2p_parse_free(&msg); 332 success = 1; 333 334 out: 335 dev->req_config_methods = 0; 336 p2p->cfg->send_action_done(p2p->cfg->cb_ctx); 337 if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) { 338 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 339 "P2P: Start GO Neg after the PD-before-GO-Neg " 340 "workaround with " MACSTR, 341 MAC2STR(dev->info.p2p_device_addr)); 342 dev->flags &= ~P2P_DEV_PD_BEFORE_GO_NEG; 343 p2p_connect_send(p2p, dev); 344 return; 345 } 346 if (success && p2p->cfg->prov_disc_resp) 347 p2p->cfg->prov_disc_resp(p2p->cfg->cb_ctx, sa, 348 report_config_methods); 349 } 350 351 352 int p2p_send_prov_disc_req(struct p2p_data *p2p, struct p2p_device *dev, 353 int join, int force_freq) 354 { 355 struct wpabuf *req; 356 int freq; 357 358 if (force_freq > 0) 359 freq = force_freq; 360 else 361 freq = dev->listen_freq > 0 ? dev->listen_freq : 362 dev->oper_freq; 363 if (freq <= 0) { 364 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 365 "P2P: No Listen/Operating frequency known for the " 366 "peer " MACSTR " to send Provision Discovery Request", 367 MAC2STR(dev->info.p2p_device_addr)); 368 return -1; 369 } 370 371 if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) { 372 if (!(dev->info.dev_capab & 373 P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) { 374 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 375 "P2P: Cannot use PD with P2P Device " MACSTR 376 " that is in a group and is not discoverable", 377 MAC2STR(dev->info.p2p_device_addr)); 378 return -1; 379 } 380 /* TODO: use device discoverability request through GO */ 381 } 382 383 req = p2p_build_prov_disc_req(p2p, dev->dialog_token, 384 dev->req_config_methods, 385 join ? dev : NULL); 386 if (req == NULL) 387 return -1; 388 389 if (p2p->state != P2P_IDLE) 390 p2p_stop_listen_for_freq(p2p, freq); 391 p2p->pending_action_state = P2P_PENDING_PD; 392 if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr, 393 p2p->cfg->dev_addr, dev->info.p2p_device_addr, 394 wpabuf_head(req), wpabuf_len(req), 200) < 0) { 395 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, 396 "P2P: Failed to send Action frame"); 397 wpabuf_free(req); 398 return -1; 399 } 400 401 os_memcpy(p2p->pending_pd_devaddr, dev->info.p2p_device_addr, ETH_ALEN); 402 403 wpabuf_free(req); 404 return 0; 405 } 406 407 408 int p2p_prov_disc_req(struct p2p_data *p2p, const u8 *peer_addr, 409 u16 config_methods, int join, int force_freq, 410 int user_initiated_pd) 411 { 412 struct p2p_device *dev; 413 414 dev = p2p_get_device(p2p, peer_addr); 415 if (dev == NULL) 416 dev = p2p_get_device_interface(p2p, peer_addr); 417 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { 418 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Provision " 419 "Discovery Request destination " MACSTR 420 " not yet known", MAC2STR(peer_addr)); 421 return -1; 422 } 423 424 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Provision Discovery " 425 "Request with " MACSTR " (config methods 0x%x)", 426 MAC2STR(peer_addr), config_methods); 427 if (config_methods == 0) 428 return -1; 429 430 /* Reset provisioning info */ 431 dev->wps_prov_info = 0; 432 433 dev->req_config_methods = config_methods; 434 if (join) 435 dev->flags |= P2P_DEV_PD_FOR_JOIN; 436 else 437 dev->flags &= ~P2P_DEV_PD_FOR_JOIN; 438 439 if (p2p->state != P2P_IDLE && p2p->state != P2P_SEARCH && 440 p2p->state != P2P_LISTEN_ONLY) { 441 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Busy with other " 442 "operations; postpone Provision Discovery Request " 443 "with " MACSTR " (config methods 0x%x)", 444 MAC2STR(peer_addr), config_methods); 445 return 0; 446 } 447 448 p2p->user_initiated_pd = user_initiated_pd; 449 450 if (p2p->user_initiated_pd) 451 p2p->pd_retries = MAX_PROV_DISC_REQ_RETRIES; 452 453 /* 454 * Assign dialog token here to use the same value in each retry within 455 * the same PD exchange. 456 */ 457 dev->dialog_token++; 458 if (dev->dialog_token == 0) 459 dev->dialog_token = 1; 460 461 return p2p_send_prov_disc_req(p2p, dev, join, force_freq); 462 } 463 464 465 void p2p_reset_pending_pd(struct p2p_data *p2p) 466 { 467 struct p2p_device *dev; 468 469 dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) { 470 if (os_memcmp(p2p->pending_pd_devaddr, 471 dev->info.p2p_device_addr, ETH_ALEN)) 472 continue; 473 if (!dev->req_config_methods) 474 continue; 475 if (dev->flags & P2P_DEV_PD_FOR_JOIN) 476 continue; 477 /* Reset the config methods of the device */ 478 dev->req_config_methods = 0; 479 } 480 481 p2p->user_initiated_pd = 0; 482 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN); 483 p2p->pd_retries = 0; 484 } 485