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 p2p_dbg(p2p, "Received Provision Discovery Request from " MACSTR 145 " with config methods 0x%x (freq=%d)", 146 MAC2STR(sa), msg.wps_config_methods, rx_freq); 147 148 dev = p2p_get_device(p2p, sa); 149 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { 150 p2p_dbg(p2p, "Provision Discovery Request from unknown peer " 151 MACSTR, MAC2STR(sa)); 152 153 if (p2p_add_device(p2p, sa, rx_freq, NULL, 0, data + 1, len - 1, 154 0)) { 155 p2p_dbg(p2p, "Provision Discovery Request add device failed " 156 MACSTR, MAC2STR(sa)); 157 } 158 } else if (msg.wfd_subelems) { 159 wpabuf_free(dev->info.wfd_subelems); 160 dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems); 161 } 162 163 if (!(msg.wps_config_methods & 164 (WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD | 165 WPS_CONFIG_PUSHBUTTON))) { 166 p2p_dbg(p2p, "Unsupported Config Methods in Provision Discovery Request"); 167 goto out; 168 } 169 170 if (msg.group_id) { 171 size_t i; 172 for (i = 0; i < p2p->num_groups; i++) { 173 if (p2p_group_is_group_id_match(p2p->groups[i], 174 msg.group_id, 175 msg.group_id_len)) 176 break; 177 } 178 if (i == p2p->num_groups) { 179 p2p_dbg(p2p, "PD request for unknown P2P Group ID - reject"); 180 goto out; 181 } 182 } 183 184 if (dev) 185 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY | 186 P2P_DEV_PD_PEER_KEYPAD); 187 if (msg.wps_config_methods & WPS_CONFIG_DISPLAY) { 188 p2p_dbg(p2p, "Peer " MACSTR 189 " requested us to show a PIN on display", MAC2STR(sa)); 190 if (dev) 191 dev->flags |= P2P_DEV_PD_PEER_KEYPAD; 192 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) { 193 p2p_dbg(p2p, "Peer " MACSTR 194 " requested us to write its PIN using keypad", 195 MAC2STR(sa)); 196 if (dev) 197 dev->flags |= P2P_DEV_PD_PEER_DISPLAY; 198 } 199 200 reject = 0; 201 202 out: 203 resp = p2p_build_prov_disc_resp(p2p, msg.dialog_token, 204 reject ? 0 : msg.wps_config_methods, 205 msg.group_id, msg.group_id_len); 206 if (resp == NULL) { 207 p2p_parse_free(&msg); 208 return; 209 } 210 p2p_dbg(p2p, "Sending Provision Discovery Response"); 211 if (rx_freq > 0) 212 freq = rx_freq; 213 else 214 freq = p2p_channel_to_freq(p2p->cfg->reg_class, 215 p2p->cfg->channel); 216 if (freq < 0) { 217 p2p_dbg(p2p, "Unknown regulatory class/channel"); 218 wpabuf_free(resp); 219 p2p_parse_free(&msg); 220 return; 221 } 222 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 223 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, 224 p2p->cfg->dev_addr, 225 wpabuf_head(resp), wpabuf_len(resp), 200) < 0) { 226 p2p_dbg(p2p, "Failed to send Action frame"); 227 } 228 229 wpabuf_free(resp); 230 231 if (!reject && p2p->cfg->prov_disc_req) { 232 const u8 *dev_addr = sa; 233 if (msg.p2p_device_addr) 234 dev_addr = msg.p2p_device_addr; 235 p2p->cfg->prov_disc_req(p2p->cfg->cb_ctx, sa, 236 msg.wps_config_methods, 237 dev_addr, msg.pri_dev_type, 238 msg.device_name, msg.config_methods, 239 msg.capability ? msg.capability[0] : 0, 240 msg.capability ? msg.capability[1] : 241 0, 242 msg.group_id, msg.group_id_len); 243 } 244 p2p_parse_free(&msg); 245 } 246 247 248 void p2p_process_prov_disc_resp(struct p2p_data *p2p, const u8 *sa, 249 const u8 *data, size_t len) 250 { 251 struct p2p_message msg; 252 struct p2p_device *dev; 253 u16 report_config_methods = 0, req_config_methods; 254 int success = 0; 255 256 if (p2p_parse(data, len, &msg)) 257 return; 258 259 p2p_dbg(p2p, "Received Provision Discovery Response from " MACSTR 260 " with config methods 0x%x", 261 MAC2STR(sa), msg.wps_config_methods); 262 263 dev = p2p_get_device(p2p, sa); 264 if (dev == NULL || !dev->req_config_methods) { 265 p2p_dbg(p2p, "Ignore Provision Discovery Response from " MACSTR 266 " with no pending request", MAC2STR(sa)); 267 p2p_parse_free(&msg); 268 return; 269 } 270 271 if (dev->dialog_token != msg.dialog_token) { 272 p2p_dbg(p2p, "Ignore Provision Discovery Response with unexpected Dialog Token %u (expected %u)", 273 msg.dialog_token, dev->dialog_token); 274 p2p_parse_free(&msg); 275 return; 276 } 277 278 if (p2p->pending_action_state == P2P_PENDING_PD) { 279 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN); 280 p2p->pending_action_state = P2P_NO_PENDING_ACTION; 281 } 282 283 /* 284 * Use a local copy of the requested config methods since 285 * p2p_reset_pending_pd() can clear this in the peer entry. 286 */ 287 req_config_methods = dev->req_config_methods; 288 289 /* 290 * If the response is from the peer to whom a user initiated request 291 * was sent earlier, we reset that state info here. 292 */ 293 if (p2p->user_initiated_pd && 294 os_memcmp(p2p->pending_pd_devaddr, sa, ETH_ALEN) == 0) 295 p2p_reset_pending_pd(p2p); 296 297 if (msg.wps_config_methods != req_config_methods) { 298 p2p_dbg(p2p, "Peer rejected our Provision Discovery Request (received config_methods 0x%x expected 0x%x", 299 msg.wps_config_methods, req_config_methods); 300 if (p2p->cfg->prov_disc_fail) 301 p2p->cfg->prov_disc_fail(p2p->cfg->cb_ctx, sa, 302 P2P_PROV_DISC_REJECTED); 303 p2p_parse_free(&msg); 304 goto out; 305 } 306 307 report_config_methods = req_config_methods; 308 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY | 309 P2P_DEV_PD_PEER_KEYPAD); 310 if (req_config_methods & WPS_CONFIG_DISPLAY) { 311 p2p_dbg(p2p, "Peer " MACSTR 312 " accepted to show a PIN on display", MAC2STR(sa)); 313 dev->flags |= P2P_DEV_PD_PEER_DISPLAY; 314 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) { 315 p2p_dbg(p2p, "Peer " MACSTR 316 " accepted to write our PIN using keypad", 317 MAC2STR(sa)); 318 dev->flags |= P2P_DEV_PD_PEER_KEYPAD; 319 } 320 321 /* Store the provisioning info */ 322 dev->wps_prov_info = msg.wps_config_methods; 323 324 p2p_parse_free(&msg); 325 success = 1; 326 327 out: 328 dev->req_config_methods = 0; 329 p2p->cfg->send_action_done(p2p->cfg->cb_ctx); 330 if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) { 331 p2p_dbg(p2p, "Start GO Neg after the PD-before-GO-Neg workaround with " 332 MACSTR, MAC2STR(dev->info.p2p_device_addr)); 333 dev->flags &= ~P2P_DEV_PD_BEFORE_GO_NEG; 334 p2p_connect_send(p2p, dev); 335 return; 336 } 337 if (success && p2p->cfg->prov_disc_resp) 338 p2p->cfg->prov_disc_resp(p2p->cfg->cb_ctx, sa, 339 report_config_methods); 340 341 if (p2p->state == P2P_PD_DURING_FIND) { 342 p2p_clear_timeout(p2p); 343 p2p_continue_find(p2p); 344 } 345 } 346 347 348 int p2p_send_prov_disc_req(struct p2p_data *p2p, struct p2p_device *dev, 349 int join, int force_freq) 350 { 351 struct wpabuf *req; 352 int freq; 353 354 if (force_freq > 0) 355 freq = force_freq; 356 else 357 freq = dev->listen_freq > 0 ? dev->listen_freq : 358 dev->oper_freq; 359 if (freq <= 0) { 360 p2p_dbg(p2p, "No Listen/Operating frequency known for the peer " 361 MACSTR " to send Provision Discovery Request", 362 MAC2STR(dev->info.p2p_device_addr)); 363 return -1; 364 } 365 366 if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) { 367 if (!(dev->info.dev_capab & 368 P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) { 369 p2p_dbg(p2p, "Cannot use PD with P2P Device " MACSTR 370 " that is in a group and is not discoverable", 371 MAC2STR(dev->info.p2p_device_addr)); 372 return -1; 373 } 374 /* TODO: use device discoverability request through GO */ 375 } 376 377 req = p2p_build_prov_disc_req(p2p, dev->dialog_token, 378 dev->req_config_methods, 379 join ? dev : NULL); 380 if (req == NULL) 381 return -1; 382 383 if (p2p->state != P2P_IDLE) 384 p2p_stop_listen_for_freq(p2p, freq); 385 p2p->pending_action_state = P2P_PENDING_PD; 386 if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr, 387 p2p->cfg->dev_addr, dev->info.p2p_device_addr, 388 wpabuf_head(req), wpabuf_len(req), 200) < 0) { 389 p2p_dbg(p2p, "Failed to send Action frame"); 390 wpabuf_free(req); 391 return -1; 392 } 393 394 os_memcpy(p2p->pending_pd_devaddr, dev->info.p2p_device_addr, ETH_ALEN); 395 396 wpabuf_free(req); 397 return 0; 398 } 399 400 401 int p2p_prov_disc_req(struct p2p_data *p2p, const u8 *peer_addr, 402 u16 config_methods, int join, int force_freq, 403 int user_initiated_pd) 404 { 405 struct p2p_device *dev; 406 407 dev = p2p_get_device(p2p, peer_addr); 408 if (dev == NULL) 409 dev = p2p_get_device_interface(p2p, peer_addr); 410 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { 411 p2p_dbg(p2p, "Provision Discovery Request destination " MACSTR 412 " not yet known", MAC2STR(peer_addr)); 413 return -1; 414 } 415 416 p2p_dbg(p2p, "Provision Discovery Request with " MACSTR 417 " (config methods 0x%x)", 418 MAC2STR(peer_addr), config_methods); 419 if (config_methods == 0) 420 return -1; 421 422 /* Reset provisioning info */ 423 dev->wps_prov_info = 0; 424 425 dev->req_config_methods = config_methods; 426 if (join) 427 dev->flags |= P2P_DEV_PD_FOR_JOIN; 428 else 429 dev->flags &= ~P2P_DEV_PD_FOR_JOIN; 430 431 if (p2p->state != P2P_IDLE && p2p->state != P2P_SEARCH && 432 p2p->state != P2P_LISTEN_ONLY) { 433 p2p_dbg(p2p, "Busy with other operations; postpone Provision Discovery Request with " 434 MACSTR " (config methods 0x%x)", 435 MAC2STR(peer_addr), config_methods); 436 return 0; 437 } 438 439 p2p->user_initiated_pd = user_initiated_pd; 440 441 if (p2p->user_initiated_pd) 442 p2p->pd_retries = MAX_PROV_DISC_REQ_RETRIES; 443 444 /* 445 * Assign dialog token here to use the same value in each retry within 446 * the same PD exchange. 447 */ 448 dev->dialog_token++; 449 if (dev->dialog_token == 0) 450 dev->dialog_token = 1; 451 452 return p2p_send_prov_disc_req(p2p, dev, join, force_freq); 453 } 454 455 456 void p2p_reset_pending_pd(struct p2p_data *p2p) 457 { 458 struct p2p_device *dev; 459 460 dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) { 461 if (os_memcmp(p2p->pending_pd_devaddr, 462 dev->info.p2p_device_addr, ETH_ALEN)) 463 continue; 464 if (!dev->req_config_methods) 465 continue; 466 if (dev->flags & P2P_DEV_PD_FOR_JOIN) 467 continue; 468 /* Reset the config methods of the device */ 469 dev->req_config_methods = 0; 470 } 471 472 p2p->user_initiated_pd = 0; 473 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN); 474 p2p->pd_retries = 0; 475 } 476
