src/p2p/p2p_invitation.c

   1 /*
   2  * Wi-Fi Direct - P2P Invitation procedure
   3  * Copyright (c) 2010, Atheros Communications
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "common/ieee802_11_defs.h"
  19 #include "p2p_i.h"
  20 #include "p2p.h"
  21
  22
  23 static struct wpabuf * p2p_build_invitation_req(struct p2p_data *p2p,
  24                                                 struct p2p_device *peer,
  25                                                 const u8 *go_dev_addr)
  26 {
  27         struct wpabuf *buf;
  28         u8 *len;
  29         const u8 *dev_addr;
  30
  31         buf = wpabuf_alloc(1000);
  32         if (buf == NULL)
  33                 return NULL;
  34
  35         peer->dialog_token++;
  36         if (peer->dialog_token == 0)
  37                 peer->dialog_token = 1;
  38         p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_REQ,
  39                                       peer->dialog_token);
  40
  41         len = p2p_buf_add_ie_hdr(buf);
  42         if (p2p->inv_role == P2P_INVITE_ROLE_ACTIVE_GO || !p2p->inv_persistent)
  43                 p2p_buf_add_config_timeout(buf, 0, 0);
  44         else
  45                 p2p_buf_add_config_timeout(buf, 100, 20);
  46         p2p_buf_add_invitation_flags(buf, p2p->inv_persistent ?
  47                                      P2P_INVITATION_FLAGS_TYPE : 0);
  48         p2p_buf_add_operating_channel(buf, p2p->cfg->country,
  49                                       p2p->op_reg_class, p2p->op_channel);
  50         if (p2p->inv_bssid_set)
  51                 p2p_buf_add_group_bssid(buf, p2p->inv_bssid);
  52         p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels);
  53         if (go_dev_addr)
  54                 dev_addr = go_dev_addr;
  55         else if (p2p->inv_role == P2P_INVITE_ROLE_CLIENT)
  56                 dev_addr = peer->p2p_device_addr;
  57         else
  58                 dev_addr = p2p->cfg->dev_addr;
  59         p2p_buf_add_group_id(buf, dev_addr, p2p->inv_ssid, p2p->inv_ssid_len);
  60         p2p_buf_add_device_info(buf, p2p, peer);
  61         p2p_buf_update_ie_hdr(buf, len);
  62
  63         return buf;
  64 }
  65
  66
  67 static struct wpabuf * p2p_build_invitation_resp(struct p2p_data *p2p,
  68                                                  struct p2p_device *peer,
  69                                                  u8 dialog_token, u8 status,
  70                                                  const u8 *group_bssid,
  71                                                  u8 reg_class, u8 channel,
  72                                                  struct p2p_channels *channels)
  73 {
  74         struct wpabuf *buf;
  75         u8 *len;
  76
  77         buf = wpabuf_alloc(1000);
  78         if (buf == NULL)
  79                 return NULL;
  80
  81         p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_RESP,
  82                                       dialog_token);
  83
  84         len = p2p_buf_add_ie_hdr(buf);
  85         p2p_buf_add_status(buf, status);
  86         p2p_buf_add_config_timeout(buf, 0, 0); /* FIX */
  87         if (reg_class && channel)
  88                 p2p_buf_add_operating_channel(buf, p2p->cfg->country,
  89                                               reg_class, channel);
  90         if (group_bssid)
  91                 p2p_buf_add_group_bssid(buf, group_bssid);
  92         if (channels)
  93                 p2p_buf_add_channel_list(buf, p2p->cfg->country, channels);
  94         p2p_buf_update_ie_hdr(buf, len);
  95
  96         return buf;
  97 }
  98
  99
 100 void p2p_process_invitation_req(struct p2p_data *p2p, const u8 *sa,
 101                                 const u8 *data, size_t len, int rx_freq)
 102 {
 103         struct p2p_device *dev;
 104         struct p2p_message msg;
 105         struct wpabuf *resp = NULL;
 106         u8 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE;
 107         int freq;
 108         int go = 0;
 109         u8 group_bssid[ETH_ALEN], *bssid;
 110         int op_freq = 0;
 111         u8 reg_class = 0, channel = 0;
 112         struct p2p_channels intersection, *channels = NULL;
 113         int persistent;
 114
 115         os_memset(group_bssid, 0, sizeof(group_bssid));
 116
 117         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 118                 "P2P: Received Invitation Request from " MACSTR " (freq=%d)",
 119                 MAC2STR(sa), rx_freq);
 120
 121         if (p2p_parse(data, len, &msg))
 122                 return;
 123
 124         dev = p2p_get_device(p2p, sa);
 125         if (dev == NULL) {
 126                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 127                         "P2P: Reject Invitation Request from unknown peer "
 128                         MACSTR, MAC2STR(sa));
 129                 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE;
 130                 goto fail;
 131         }
 132
 133         if (!msg.group_id || !msg.channel_list) {
 134                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 135                         "P2P: Mandatory attribute missing in Invitation "
 136                         "Request from " MACSTR, MAC2STR(sa));
 137                 status = P2P_SC_FAIL_INVALID_PARAMS;
 138                 goto fail;
 139         }
 140
 141         if (msg.invitation_flags)
 142                 persistent = *msg.invitation_flags & P2P_INVITATION_FLAGS_TYPE;
 143         else {
 144                 /* Invitation Flags is a mandatory attribute starting from P2P
 145                  * spec 1.06. As a backwards compatibility mechanism, assume
 146                  * the request was for a persistent group if the attribute is
 147                  * missing.
 148                  */
 149                 wpa_printf(MSG_DEBUG, "P2P: Mandatory Invitation Flags "
 150                            "attribute missing from Invitation Request");
 151                 persistent = 1;
 152         }
 153
 154         if (p2p_peer_channels_check(p2p, &p2p->cfg->channels, dev,
 155                                     msg.channel_list, msg.channel_list_len) <
 156             0) {
 157                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 158                         "P2P: No common channels found");
 159                 status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
 160                 goto fail;
 161         }
 162
 163         if (p2p->cfg->invitation_process) {
 164                 status = p2p->cfg->invitation_process(
 165                         p2p->cfg->cb_ctx, sa, msg.group_bssid, msg.group_id,
 166                         msg.group_id + ETH_ALEN, msg.group_id_len - ETH_ALEN,
 167                         &go, group_bssid, &op_freq, persistent);
 168         }
 169
 170         if (op_freq) {
 171                 if (p2p_freq_to_channel(p2p->cfg->country, op_freq,
 172                                         &reg_class, &channel) < 0) {
 173                         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 174                                 "P2P: Unknown forced freq %d MHz from "
 175                                 "invitation_process()", op_freq);
 176                         status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
 177                         goto fail;
 178                 }
 179
 180                 p2p_channels_intersect(&p2p->cfg->channels, &dev->channels,
 181                                        &intersection);
 182                 if (!p2p_channels_includes(&intersection, reg_class, channel))
 183                 {
 184                         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 185                                 "P2P: forced freq %d MHz not in the supported "
 186                                 "channels interaction", op_freq);
 187                         status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
 188                         goto fail;
 189                 }
 190
 191                 if (status == P2P_SC_SUCCESS)
 192                         channels = &intersection;
 193         } else {
 194                 op_freq = p2p_channel_to_freq(p2p->cfg->country,
 195                                               p2p->cfg->op_reg_class,
 196                                               p2p->cfg->op_channel);
 197                 if (op_freq < 0) {
 198                         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 199                                 "P2P: Unknown operational channel "
 200                                 "(country=%c%c reg_class=%u channel=%u)",
 201                                 p2p->cfg->country[0], p2p->cfg->country[1],
 202                                 p2p->cfg->op_reg_class, p2p->cfg->op_channel);
 203                         status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
 204                         goto fail;
 205                 }
 206
 207                 p2p_channels_intersect(&p2p->cfg->channels, &dev->channels,
 208                                        &intersection);
 209                 if (status == P2P_SC_SUCCESS) {
 210                         reg_class = p2p->cfg->op_reg_class;
 211                         channel = p2p->cfg->op_channel;
 212                         channels = &intersection;
 213                 }
 214         }
 215
 216 fail:
 217         if (go && status == P2P_SC_SUCCESS && !is_zero_ether_addr(group_bssid))
 218                 bssid = group_bssid;
 219         else
 220                 bssid = NULL;
 221         resp = p2p_build_invitation_resp(p2p, dev, msg.dialog_token, status,
 222                                          bssid, reg_class, channel, channels);
 223
 224         if (resp == NULL)
 225                 goto out;
 226
 227         if (rx_freq > 0)
 228                 freq = rx_freq;
 229         else
 230                 freq = p2p_channel_to_freq(p2p->cfg->country,
 231                                            p2p->cfg->reg_class,
 232                                            p2p->cfg->channel);
 233         if (freq < 0) {
 234                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 235                         "P2P: Unknown regulatory class/channel");
 236                 goto out;
 237         }
 238
 239         /*
 240          * Store copy of invitation data to be used when processing TX status
 241          * callback for the Acton frame.
 242          */
 243         os_memcpy(p2p->inv_sa, sa, ETH_ALEN);
 244         if (msg.group_bssid) {
 245                 os_memcpy(p2p->inv_group_bssid, msg.group_bssid, ETH_ALEN);
 246                 p2p->inv_group_bssid_ptr = p2p->inv_group_bssid;
 247         } else
 248                 p2p->inv_group_bssid_ptr = NULL;
 249         if (msg.group_id_len - ETH_ALEN <= 32) {
 250                 os_memcpy(p2p->inv_ssid, msg.group_id + ETH_ALEN,
 251                           msg.group_id_len - ETH_ALEN);
 252                 p2p->inv_ssid_len = msg.group_id_len - ETH_ALEN;
 253         }
 254         os_memcpy(p2p->inv_go_dev_addr, msg.group_id, ETH_ALEN);
 255         p2p->inv_status = status;
 256         p2p->inv_op_freq = op_freq;
 257
 258         p2p->pending_action_state = P2P_PENDING_INVITATION_RESPONSE;
 259         if (p2p->cfg->send_action(p2p->cfg->cb_ctx, freq, sa,
 260                                   p2p->cfg->dev_addr, p2p->cfg->dev_addr,
 261                                   wpabuf_head(resp), wpabuf_len(resp), 200) <
 262             0) {
 263                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 264                         "P2P: Failed to send Action frame");
 265         }
 266
 267 out:
 268         wpabuf_free(resp);
 269         p2p_parse_free(&msg);
 270 }
 271
 272
 273 void p2p_process_invitation_resp(struct p2p_data *p2p, const u8 *sa,
 274                                  const u8 *data, size_t len)
 275 {
 276         struct p2p_device *dev;
 277         struct p2p_message msg;
 278
 279         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 280                 "P2P: Received Invitation Response from " MACSTR,
 281                 MAC2STR(sa));
 282
 283         dev = p2p_get_device(p2p, sa);
 284         if (dev == NULL) {
 285                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 286                         "P2P: Ignore Invitation Response from unknown peer "
 287                         MACSTR, MAC2STR(sa));
 288                 return;
 289         }
 290
 291         if (dev != p2p->invite_peer) {
 292                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 293                         "P2P: Ignore unexpected Invitation Response from peer "
 294                         MACSTR, MAC2STR(sa));
 295                 return;
 296         }
 297
 298         if (p2p_parse(data, len, &msg))
 299                 return;
 300
 301         if (!msg.status) {
 302                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 303                         "P2P: Mandatory Status attribute missing in "
 304                         "Invitation Response from " MACSTR, MAC2STR(sa));
 305                 p2p_parse_free(&msg);
 306                 return;
 307         }
 308
 309         if (p2p->cfg->invitation_result)
 310                 p2p->cfg->invitation_result(p2p->cfg->cb_ctx, *msg.status,
 311                                             msg.group_bssid);
 312
 313         p2p_parse_free(&msg);
 314
 315         p2p_clear_timeout(p2p);
 316         p2p_set_state(p2p, P2P_IDLE);
 317         p2p->invite_peer = NULL;
 318 }
 319
 320
 321 int p2p_invite_send(struct p2p_data *p2p, struct p2p_device *dev,
 322                     const u8 *go_dev_addr)
 323 {
 324         struct wpabuf *req;
 325         int freq;
 326
 327         freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
 328         if (freq <= 0) {
 329                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 330                         "P2P: No Listen/Operating frequency known for the "
 331                         "peer " MACSTR " to send Invitation Request",
 332                         MAC2STR(dev->p2p_device_addr));
 333                 return -1;
 334         }
 335
 336         req = p2p_build_invitation_req(p2p, dev, go_dev_addr);
 337         if (req == NULL)
 338                 return -1;
 339         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 340                 "P2P: Sending Invitation Request");
 341         p2p_set_state(p2p, P2P_INVITE);
 342         p2p->pending_action_state = P2P_PENDING_INVITATION_REQUEST;
 343         p2p->invite_peer = dev;
 344         dev->invitation_reqs++;
 345         if (p2p->cfg->send_action(p2p->cfg->cb_ctx, freq,
 346                                   dev->p2p_device_addr, p2p->cfg->dev_addr,
 347                                   dev->p2p_device_addr,
 348                                   wpabuf_head(req), wpabuf_len(req), 200) < 0)
 349         {
 350                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 351                         "P2P: Failed to send Action frame");
 352                 /* Use P2P find to recover and retry */
 353                 p2p_set_timeout(p2p, 0, 0);
 354         }
 355
 356         wpabuf_free(req);
 357
 358         return 0;
 359 }
 360
 361
 362 void p2p_invitation_req_cb(struct p2p_data *p2p, int success)
 363 {
 364         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 365                 "P2P: Invitation Request TX callback: success=%d", success);
 366
 367         if (p2p->invite_peer == NULL) {
 368                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 369                         "P2P: No pending Invite");
 370                 return;
 371         }
 372
 373         /*
 374          * Use P2P find, if needed, to find the other device from its listen
 375          * channel.
 376          */
 377         p2p_set_state(p2p, P2P_INVITE);
 378         p2p_set_timeout(p2p, 0, 100000);
 379 }
 380
 381
 382 void p2p_invitation_resp_cb(struct p2p_data *p2p, int success)
 383 {
 384         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 385                 "P2P: Invitation Response TX callback: success=%d", success);
 386         p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
 387
 388         if (success && p2p->cfg->invitation_received) {
 389                 p2p->cfg->invitation_received(p2p->cfg->cb_ctx,
 390                                               p2p->inv_sa,
 391                                               p2p->inv_group_bssid,
 392                                               p2p->inv_ssid, p2p->inv_ssid_len,
 393                                               p2p->inv_go_dev_addr,
 394                                               p2p->inv_status,
 395                                               p2p->inv_op_freq);
 396         }
 397 }
 398
 399
 400 int p2p_invite(struct p2p_data *p2p, const u8 *peer, enum p2p_invite_role role,
 401                const u8 *bssid, const u8 *ssid, size_t ssid_len,
 402                unsigned int force_freq, const u8 *go_dev_addr,
 403                int persistent_group)
 404 {
 405         struct p2p_device *dev;
 406
 407         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 408                 "P2P: Request to invite peer " MACSTR " role=%d persistent=%d "
 409                 "force_freq=%u",
 410                 MAC2STR(peer), role, persistent_group, force_freq);
 411         if (bssid)
 412                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 413                         "P2P: Invitation for BSSID " MACSTR, MAC2STR(bssid));
 414         if (go_dev_addr) {
 415                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 416                         "P2P: Invitation for GO Device Address " MACSTR,
 417                         MAC2STR(go_dev_addr));
 418                 os_memcpy(p2p->invite_go_dev_addr_buf, go_dev_addr, ETH_ALEN);
 419                 p2p->invite_go_dev_addr = p2p->invite_go_dev_addr_buf;
 420         } else
 421                 p2p->invite_go_dev_addr = NULL;
 422         wpa_hexdump_ascii(MSG_DEBUG, "P2P: Invitation for SSID",
 423                           ssid, ssid_len);
 424
 425         dev = p2p_get_device(p2p, peer);
 426         if (dev == NULL || (dev->listen_freq <= 0 && dev->oper_freq <= 0)) {
 427                 wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 428                         "P2P: Cannot invite unknown P2P Device " MACSTR,
 429                         MAC2STR(peer));
 430                 return -1;
 431         }
 432
 433         if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) {
 434                 if (!(dev->dev_capab & P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) {
 435                         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 436                                 "P2P: Cannot invite a P2P Device " MACSTR
 437                                 " that is in a group and is not discoverable",
 438                                 MAC2STR(peer));
 439                 }
 440                 /* TODO: use device discoverability request through GO */
 441         }
 442
 443         dev->invitation_reqs = 0;
 444
 445         if (force_freq) {
 446                 if (p2p_freq_to_channel(p2p->cfg->country, force_freq,
 447                                         &p2p->op_reg_class, &p2p->op_channel) <
 448                     0) {
 449                         wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
 450                                 "P2P: Unsupported frequency %u MHz",
 451                                 force_freq);
 452                         return -1;
 453                 }
 454                 p2p->channels.reg_classes = 1;
 455                 p2p->channels.reg_class[0].channels = 1;
 456                 p2p->channels.reg_class[0].reg_class = p2p->op_reg_class;
 457                 p2p->channels.reg_class[0].channel[0] = p2p->op_channel;
 458         } else {
 459                 p2p->op_reg_class = p2p->cfg->op_reg_class;
 460                 p2p->op_channel = p2p->cfg->op_channel;
 461                 os_memcpy(&p2p->channels, &p2p->cfg->channels,
 462                           sizeof(struct p2p_channels));
 463         }
 464
 465         if (p2p->state != P2P_IDLE)
 466                 p2p_stop_find(p2p);
 467
 468         p2p->inv_role = role;
 469         p2p->inv_bssid_set = bssid != NULL;
 470         if (bssid)
 471                 os_memcpy(p2p->inv_bssid, bssid, ETH_ALEN);
 472         os_memcpy(p2p->inv_ssid, ssid, ssid_len);
 473         p2p->inv_ssid_len = ssid_len;
 474         p2p->inv_persistent = persistent_group;
 475         return p2p_invite_send(p2p, dev, go_dev_addr);
 476 }