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