/src/hostap/src/p2p/p2p_go_neg.c

Source
/*
 * Wi-Fi Direct - P2P Group Owner Negotiation
 * Copyright (c) 2009-2010, Atheros Communications
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "includes.h"

#include "common.h"
#include "utils/eloop.h"
#include "common/ieee802_11_defs.h"
#include "common/ieee802_11_common.h"
#include "common/wpa_ctrl.h"
#include "wps/wps_defs.h"
#include "p2p_i.h"
#include "p2p.h"


static int p2p_go_det(u8 own_intent, u8 peer_value)
{
  u8 peer_intent = peer_value >> 1;
  if (own_intent == peer_intent) {
    if (own_intent == P2P_MAX_GO_INTENT)
      return -1; /* both devices want to become GO */

    /* Use tie breaker bit to determine GO */
    return (peer_value & 0x01) ? 0 : 1;
  }

  return own_intent > peer_intent;
}


int p2p_peer_channels_check(struct p2p_data *p2p, struct p2p_channels *own,
          struct p2p_device *dev,
          const u8 *channel_list, size_t channel_list_len)
{
  const u8 *pos, *end;
  struct p2p_channels *ch;
  u8 channels;
  struct p2p_channels intersection;

  ch = &dev->channels;
  os_memset(ch, 0, sizeof(*ch));
  pos = channel_list;
  end = channel_list + channel_list_len;

  if (end - pos < 3)
    return -1;
  os_memcpy(dev->country, pos, 3);
  wpa_hexdump_ascii(MSG_DEBUG, "P2P: Peer country", pos, 3);
  if (pos[2] != 0x04 && os_memcmp(pos, p2p->cfg->country, 2) != 0) {
    p2p_info(p2p, "Mismatching country (ours=%c%c peer's=%c%c)",
      p2p->cfg->country[0], p2p->cfg->country[1],
      pos[0], pos[1]);
    return -1;
  }
  pos += 3;

  while (end - pos > 2) {
    struct p2p_reg_class *cl = &ch->reg_class[ch->reg_classes];
    cl->reg_class = *pos++;
    channels = *pos++;
    if (channels > end - pos) {
      p2p_info(p2p, "Invalid peer Channel List");
      return -1;
    }
    cl->channels = channels > P2P_MAX_REG_CLASS_CHANNELS ?
      P2P_MAX_REG_CLASS_CHANNELS : channels;
    os_memcpy(cl->channel, pos, cl->channels);
    pos += channels;
    ch->reg_classes++;
    if (ch->reg_classes == P2P_MAX_REG_CLASSES)
      break;
  }

  p2p_channels_intersect(own, &dev->channels, &intersection);
  p2p_dbg(p2p, "Own reg_classes %d peer reg_classes %d intersection reg_classes %d",
    (int) own->reg_classes,
    (int) dev->channels.reg_classes,
    (int) intersection.reg_classes);
  if (intersection.reg_classes == 0) {
    p2p_info(p2p, "No common channels found");
    return -1;
  }
  return 0;
}


static int p2p_peer_channels(struct p2p_data *p2p, struct p2p_device *dev,
           const u8 *channel_list, size_t channel_list_len)
{
  return p2p_peer_channels_check(p2p, &p2p->channels, dev,
               channel_list, channel_list_len);
}


u16 p2p_wps_method_pw_id(enum p2p_wps_method wps_method)
{
  switch (wps_method) {
  case WPS_PIN_DISPLAY:
    return DEV_PW_REGISTRAR_SPECIFIED;
  case WPS_PIN_KEYPAD:
    return DEV_PW_USER_SPECIFIED;
  case WPS_PBC:
    return DEV_PW_PUSHBUTTON;
  case WPS_NFC:
    return DEV_PW_NFC_CONNECTION_HANDOVER;
  case WPS_P2PS:
    return DEV_PW_P2PS_DEFAULT;
  default:
    return DEV_PW_DEFAULT;
  }
}


static const char * p2p_wps_method_str(enum p2p_wps_method wps_method)
{
  switch (wps_method) {
  case WPS_PIN_DISPLAY:
    return "Display";
  case WPS_PIN_KEYPAD:
    return "Keypad";
  case WPS_PBC:
    return "PBC";
  case WPS_NFC:
    return "NFC";
  case WPS_P2PS:
    return "P2PS";
  default:
    return "??";
  }
}


struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
             struct p2p_device *peer)
{
  struct wpabuf *buf;
  struct wpabuf *subelems;
  u8 group_capab;
  size_t extra = 0;
  u16 pw_id;
  bool is_6ghz_capab;

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ])
    extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ]);

  buf = wpabuf_alloc(1000 + extra);
  if (buf == NULL)
    return NULL;

  p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_REQ, peer->dialog_token);

  subelems = wpabuf_alloc(500);
  if (!subelems) {
    wpabuf_free(buf);
    return NULL;
  }

  group_capab = 0;
  if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
    group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
    if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
      group_capab |= P2P_GROUP_CAPAB_PERSISTENT_RECONN;
  }
  if (p2p->cross_connect)
    group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
  if (p2p->cfg->p2p_intra_bss)
    group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
  p2p_buf_add_capability(subelems, p2p->dev_capab &
             ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
             group_capab);
  p2p_buf_add_go_intent(subelems,
            (p2p->go_intent << 1) | peer->tie_breaker);
  p2p_buf_add_config_timeout(subelems, p2p->go_timeout,
           p2p->client_timeout);
  p2p_buf_add_listen_channel(subelems, p2p->cfg->country,
           p2p->cfg->reg_class,
           p2p->cfg->channel);
  if (p2p->ext_listen_interval)
    p2p_buf_add_ext_listen_timing(subelems, p2p->ext_listen_period,
                p2p->ext_listen_interval);
  p2p_buf_add_intended_addr(subelems, p2p->intended_addr);
  is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
    p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
  if (p2p->num_pref_freq) {
    bool go = p2p->go_intent == 15;
    struct p2p_channels pref_chanlist;

    p2p_pref_channel_filter(&p2p->channels, p2p->pref_freq_list,
          p2p->num_pref_freq, &pref_chanlist, go);
    p2p_channels_dump(p2p, "channel list after filtering",
          &pref_chanlist);
    p2p_buf_add_channel_list(subelems, p2p->cfg->country,
           &pref_chanlist, is_6ghz_capab);
  } else {
    p2p_buf_add_channel_list(subelems, p2p->cfg->country,
           &p2p->channels, is_6ghz_capab);
  }
  p2p_buf_add_device_info(subelems, p2p, peer);
  p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
              p2p->op_reg_class, p2p->op_channel);

  p2p_buf_add_pref_channel_list(buf, p2p->pref_freq_list,
              p2p->num_pref_freq);

  /* WPS IE with Device Password ID attribute */
  pw_id = p2p_wps_method_pw_id(peer->wps_method);
  if (peer->oob_pw_id)
    pw_id = peer->oob_pw_id;
  if (!peer->p2p2 && p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
    p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Request");
    wpabuf_free(subelems);
    wpabuf_free(buf);
    return NULL;
  }

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ])
    wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ]);

  buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
  wpabuf_free(subelems);
  return buf;
}


int p2p_connect_send(struct p2p_data *p2p, struct p2p_device *dev)
{
  struct wpabuf *req;
  int freq;

  if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) {
    u16 config_method;
    p2p_dbg(p2p, "Use PD-before-GO-Neg workaround for " MACSTR,
      MAC2STR(dev->info.p2p_device_addr));
    if (dev->wps_method == WPS_PIN_DISPLAY)
      config_method = WPS_CONFIG_KEYPAD;
    else if (dev->wps_method == WPS_PIN_KEYPAD)
      config_method = WPS_CONFIG_DISPLAY;
    else if (dev->wps_method == WPS_PBC)
      config_method = WPS_CONFIG_PUSHBUTTON;
    else if (dev->wps_method == WPS_P2PS)
      config_method = WPS_CONFIG_P2PS;
    else if (dev->p2p2 && dev->req_bootstrap_method)
      config_method = WPS_NOT_READY;
    else
      return -1;
    return p2p_prov_disc_req(p2p, dev->info.p2p_device_addr,
           NULL, config_method, 0, 0, 1);
  } else if (dev->p2p2) {
    return 0;
  }

  freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
  if (dev->oob_go_neg_freq > 0)
    freq = dev->oob_go_neg_freq;
  if (freq <= 0) {
    p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
      MACSTR " to send GO Negotiation Request",
      MAC2STR(dev->info.p2p_device_addr));
    return -1;
  }

  req = p2p_build_go_neg_req(p2p, dev);
  if (req == NULL)
    return -1;
  p2p_dbg(p2p, "Sending GO Negotiation Request");
  p2p_set_state(p2p, P2P_CONNECT);
  p2p->pending_action_state = P2P_PENDING_GO_NEG_REQUEST;
  p2p->go_neg_peer = dev;
  eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);
  dev->flags |= P2P_DEV_WAIT_GO_NEG_RESPONSE;
  dev->connect_reqs++;
  if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
          p2p->cfg->dev_addr, dev->info.p2p_device_addr,
          wpabuf_head(req), wpabuf_len(req), 500) < 0) {
    p2p_dbg(p2p, "Failed to send Action frame");
    /* Use P2P find to recover and retry */
    p2p_set_timeout(p2p, 0, 0);
  } else
    dev->go_neg_req_sent++;

  wpabuf_free(req);

  return 0;
}


static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
               struct p2p_device *peer,
               u8 dialog_token, u8 status,
               u8 tie_breaker)
{
  struct wpabuf *buf;
  struct wpabuf *subelems;
  u8 group_capab;
  size_t extra = 0;
  u16 pw_id;
  bool is_6ghz_capab;
  struct p2p_channels pref_chanlist;

  p2p_dbg(p2p, "Building GO Negotiation Response");

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP])
    extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP]);

  buf = wpabuf_alloc(1000 + extra);
  if (buf == NULL)
    return NULL;

  p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_RESP, dialog_token);

  subelems = wpabuf_alloc(500);
  if (!subelems) {
    wpabuf_free(buf);
    return NULL;
  }

  p2p_buf_add_status(subelems, status);
  group_capab = 0;
  if (peer && peer->go_state == LOCAL_GO) {
    if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
      group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
      if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
        group_capab |=
          P2P_GROUP_CAPAB_PERSISTENT_RECONN;
    }
    if (p2p->cross_connect)
      group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
    if (p2p->cfg->p2p_intra_bss)
      group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
  }
  p2p_buf_add_capability(subelems, p2p->dev_capab &
             ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
             group_capab);
  p2p_buf_add_go_intent(subelems, (p2p->go_intent << 1) | tie_breaker);
  p2p_buf_add_config_timeout(subelems, p2p->go_timeout,
           p2p->client_timeout);
  if (p2p->override_pref_op_class) {
    p2p_dbg(p2p, "Override operating channel preference");
    p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                p2p->override_pref_op_class,
                p2p->override_pref_channel);
  } else if (peer && peer->go_state == REMOTE_GO && !p2p->num_pref_freq) {
    p2p_dbg(p2p, "Omit Operating Channel attribute");
  } else {
    p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                p2p->op_reg_class,
                p2p->op_channel);
  }
  p2p_buf_add_intended_addr(subelems, p2p->intended_addr);

  if (p2p->num_pref_freq) {
    bool go = (peer && peer->go_state == LOCAL_GO) ||
      p2p->go_intent == 15;

    p2p_pref_channel_filter(&p2p->channels, p2p->pref_freq_list,
          p2p->num_pref_freq, &pref_chanlist, go);
    p2p_channels_dump(p2p, "channel list after filtering",
          &pref_chanlist);
  } else {
    p2p_copy_channels(&pref_chanlist, &p2p->channels,
          p2p->allow_6ghz);
  }
  if (status || peer == NULL) {
    p2p_buf_add_channel_list(subelems, p2p->cfg->country,
           &pref_chanlist, false);
  } else if (peer->go_state == REMOTE_GO) {
    is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
      p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
    p2p_buf_add_channel_list(subelems, p2p->cfg->country,
           &pref_chanlist, is_6ghz_capab);
  } else {
    struct p2p_channels res;

    is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
      p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
    p2p_channels_intersect(&pref_chanlist, &peer->channels,
               &res);
    p2p_buf_add_channel_list(subelems, p2p->cfg->country, &res,
           is_6ghz_capab);
  }
  p2p_buf_add_device_info(subelems, p2p, peer);
  if (peer && peer->go_state == LOCAL_GO) {
    p2p_buf_add_group_id(subelems, p2p->cfg->dev_addr, p2p->ssid,
             p2p->ssid_len);
  }

  /* WPS IE with Device Password ID attribute */
  pw_id = p2p_wps_method_pw_id(peer ? peer->wps_method : WPS_NOT_READY);
  if (peer && peer->oob_pw_id)
    pw_id = peer->oob_pw_id;
  if (peer && !peer->p2p2 && p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
    p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Response");
    wpabuf_free(subelems);
    wpabuf_free(buf);
    return NULL;
  }

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP])
    wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP]);

  buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
  wpabuf_free(subelems);
  return buf;
}


/**
 * p2p_reselect_channel - Re-select operating channel based on peer information
 * @p2p: P2P module context from p2p_init()
 * @intersection: Support channel list intersection from local and peer
 *
 * This function is used to re-select the best channel after having received
 * information from the peer to allow supported channel lists to be intersected.
 * This can be used to improve initial channel selection done in
 * p2p_prepare_channel() prior to the start of GO Negotiation. In addition, this
 * can be used for Invitation case.
 */
void p2p_reselect_channel(struct p2p_data *p2p,
        struct p2p_channels *intersection)
{
  struct p2p_reg_class *cl;
  int freq;
  u8 op_reg_class, op_channel;
  unsigned int i;
  const int op_classes_5ghz[] = { 124, 125, 115, 0 };
  const int op_classes_ht40[] = { 126, 127, 116, 117, 0 };
  const int op_classes_vht[] = { 128, 129, 130, 0 };
  const int op_classes_edmg[] = { 181, 182, 183, 0 };

  if (p2p->own_freq_preference > 0 &&
      p2p_freq_to_channel(p2p->own_freq_preference,
        &op_reg_class, &op_channel) == 0 &&
      p2p_channels_includes(intersection, op_reg_class, op_channel)) {
    p2p_dbg(p2p, "Pick own channel preference (reg_class %u channel %u) from intersection",
      op_reg_class, op_channel);
    p2p->op_reg_class = op_reg_class;
    p2p->op_channel = op_channel;
    return;
  }

  if (p2p->best_freq_overall > 0 &&
      p2p_freq_to_channel(p2p->best_freq_overall,
        &op_reg_class, &op_channel) == 0 &&
      p2p_channels_includes(intersection, op_reg_class, op_channel)) {
    p2p_dbg(p2p, "Pick best overall channel (reg_class %u channel %u) from intersection",
      op_reg_class, op_channel);
    p2p->op_reg_class = op_reg_class;
    p2p->op_channel = op_channel;
    return;
  }

  /* First, try to pick the best channel from another band */
  freq = p2p_channel_to_freq(p2p->op_reg_class, p2p->op_channel);
  if (freq >= 2400 && freq < 2500 && p2p->best_freq_5 > 0 &&
      !p2p_channels_includes(intersection, p2p->op_reg_class,
           p2p->op_channel) &&
      p2p_freq_to_channel(p2p->best_freq_5,
        &op_reg_class, &op_channel) == 0 &&
      p2p_channels_includes(intersection, op_reg_class, op_channel)) {
    p2p_dbg(p2p, "Pick best 5 GHz channel (reg_class %u channel %u) from intersection",
      op_reg_class, op_channel);
    p2p->op_reg_class = op_reg_class;
    p2p->op_channel = op_channel;
    return;
  }

  if (freq >= 4900 && freq < 6000 && p2p->best_freq_24 > 0 &&
      !p2p_channels_includes(intersection, p2p->op_reg_class,
           p2p->op_channel) &&
      p2p_freq_to_channel(p2p->best_freq_24,
        &op_reg_class, &op_channel) == 0 &&
      p2p_channels_includes(intersection, op_reg_class, op_channel)) {
    p2p_dbg(p2p, "Pick best 2.4 GHz channel (reg_class %u channel %u) from intersection",
      op_reg_class, op_channel);
    p2p->op_reg_class = op_reg_class;
    p2p->op_channel = op_channel;
    return;
  }

  /* Select channel with highest preference if the peer supports it */
  for (i = 0; p2p->cfg->pref_chan && i < p2p->cfg->num_pref_chan; i++) {
    if (p2p_channels_includes(intersection,
            p2p->cfg->pref_chan[i].op_class,
            p2p->cfg->pref_chan[i].chan)) {
      p2p->op_reg_class = p2p->cfg->pref_chan[i].op_class;
      p2p->op_channel = p2p->cfg->pref_chan[i].chan;
      p2p_dbg(p2p, "Pick highest preferred channel (op_class %u channel %u) from intersection",
        p2p->op_reg_class, p2p->op_channel);
      return;
    }
  }

  /* Try a channel where we might be able to use EDMG */
  if (p2p_channel_select(intersection, op_classes_edmg,
             &p2p->op_reg_class, &p2p->op_channel) == 0) {
    p2p_dbg(p2p, "Pick possible EDMG channel (op_class %u channel %u) from intersection",
      p2p->op_reg_class, p2p->op_channel);
    return;
  }

  /* Try a channel where we might be able to use VHT */
  if (p2p_channel_select(intersection, op_classes_vht,
             &p2p->op_reg_class, &p2p->op_channel) == 0) {
    p2p_dbg(p2p, "Pick possible VHT channel (op_class %u channel %u) from intersection",
      p2p->op_reg_class, p2p->op_channel);
    return;
  }

  /* Try a channel where we might be able to use HT40 */
  if (p2p_channel_select(intersection, op_classes_ht40,
             &p2p->op_reg_class, &p2p->op_channel) == 0) {
    p2p_dbg(p2p, "Pick possible HT40 channel (op_class %u channel %u) from intersection",
      p2p->op_reg_class, p2p->op_channel);
    return;
  }

  /* Prefer a 5 GHz channel */
  if (p2p_channel_select(intersection, op_classes_5ghz,
             &p2p->op_reg_class, &p2p->op_channel) == 0) {
    p2p_dbg(p2p, "Pick possible 5 GHz channel (op_class %u channel %u) from intersection",
      p2p->op_reg_class, p2p->op_channel);
    return;
  }

  /*
   * Try to see if the original channel is in the intersection. If
   * so, no need to change anything, as it already contains some
   * randomness.
   */
  if (p2p_channels_includes(intersection, p2p->op_reg_class,
          p2p->op_channel)) {
    p2p_dbg(p2p, "Using original operating class and channel (op_class %u channel %u) from intersection",
      p2p->op_reg_class, p2p->op_channel);
    return;
  }

  /*
   * Fall back to whatever is included in the channel intersection since
   * no better options seems to be available.
   */
  cl = &intersection->reg_class[0];
  p2p_dbg(p2p, "Pick another channel (reg_class %u channel %u) from intersection",
    cl->reg_class, cl->channel[0]);
  p2p->op_reg_class = cl->reg_class;
  p2p->op_channel = cl->channel[0];
}


int p2p_go_select_channel(struct p2p_data *p2p, struct p2p_device *dev,
        u8 *status)
{
  struct p2p_channels tmp, intersection;

  p2p_channels_dump(p2p, "own channels", &p2p->channels);
  p2p_channels_dump(p2p, "peer channels", &dev->channels);
  p2p_channels_intersect(&p2p->channels, &dev->channels, &tmp);
  p2p_channels_dump(p2p, "intersection", &tmp);
  p2p_channels_remove_freqs(&tmp, &p2p->no_go_freq);
  p2p_channels_dump(p2p, "intersection after no-GO removal", &tmp);
  p2p_channels_intersect(&tmp, &p2p->cfg->channels, &intersection);
  p2p_channels_dump(p2p, "intersection with local channel list",
        &intersection);
  if (intersection.reg_classes == 0 ||
      intersection.reg_class[0].channels == 0) {
    *status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
    p2p_dbg(p2p, "No common channels found");
    return -1;
  }

  if (!p2p_channels_includes(&intersection, p2p->op_reg_class,
           p2p->op_channel)) {
    if (dev->flags & P2P_DEV_FORCE_FREQ) {
      *status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
      p2p_dbg(p2p, "Peer does not support the forced channel");
      return -1;
    }

    p2p_dbg(p2p, "Selected operating channel (op_class %u channel %u) not acceptable to the peer",
      p2p->op_reg_class, p2p->op_channel);
    p2p_reselect_channel(p2p, &intersection);
  } else if (!(dev->flags & P2P_DEV_FORCE_FREQ) &&
       !p2p->cfg->cfg_op_channel) {
    p2p_dbg(p2p, "Try to optimize channel selection with peer information received; previously selected op_class %u channel %u",
      p2p->op_reg_class, p2p->op_channel);
    p2p_reselect_channel(p2p, &intersection);
  }

  if (!p2p->ssid_set) {
    p2p_build_ssid(p2p, p2p->ssid, &p2p->ssid_len);
    p2p->ssid_set = 1;
  }

  return 0;
}


static void p2p_check_pref_chan_no_recv(struct p2p_data *p2p, int go,
          struct p2p_device *dev,
          struct p2p_message *msg,
          const struct weighted_pcl freq_list[],
          unsigned int size)
{
  u8 op_class, op_channel;
  unsigned int oper_freq = 0, i, j;
  int found = 0;

  p2p_dbg(p2p,
    "Peer didn't provide a preferred frequency list, see if any of our preferred channels are supported by peer device");

  /*
   * Search for a common channel in our preferred frequency list which is
   * also supported by the peer device.
   */
  for (i = 0; i < size && !found; i++) {
    /* Make sure that the common frequency is supported by peer. */
    oper_freq = freq_list[i].freq;
    if (p2p_freq_to_channel(oper_freq, &op_class,
          &op_channel) < 0 ||
        !p2p_pref_freq_allowed(&freq_list[i], go))
      continue;
    for (j = 0; j < msg->channel_list_len; j++) {
      if (!msg->channel_list ||
          op_channel != msg->channel_list[j])
        continue;

      p2p->op_reg_class = op_class;
      p2p->op_channel = op_channel;
      os_memcpy(&p2p->channels, &p2p->cfg->channels,
          sizeof(struct p2p_channels));
      found = 1;
      break;
    }
  }

  if (found) {
    p2p_dbg(p2p,
      "Freq %d MHz is a preferred channel and is also supported by peer, use it as the operating channel",
      oper_freq);
  } else {
    p2p_dbg(p2p,
      "None of our preferred channels are supported by peer!");
  }
}


static void p2p_check_pref_chan_recv(struct p2p_data *p2p, int go,
             struct p2p_device *dev,
             struct p2p_message *msg,
             const struct weighted_pcl freq_list[],
             unsigned int size)
{
  u8 op_class, op_channel;
  unsigned int oper_freq = 0, i, j;
  int found = 0;

  /*
   * Peer device supports a Preferred Frequency List.
   * Search for a common channel in the preferred frequency lists
   * of both peer and local devices.
   */
  for (i = 0; i < size && !found; i++) {
    for (j = 2; j < (msg->pref_freq_list_len / 2); j++) {
      oper_freq = p2p_channel_to_freq(
        msg->pref_freq_list[2 * j],
        msg->pref_freq_list[2 * j + 1]);
      if (freq_list[i].freq != oper_freq)
        continue;
      if (p2p_freq_to_channel(oper_freq, &op_class,
            &op_channel) < 0)
        continue; /* cannot happen */
      if (!p2p_pref_freq_allowed(&freq_list[i], go))
        break;
      p2p->op_reg_class = op_class;
      p2p->op_channel = op_channel;
      os_memcpy(&p2p->channels, &p2p->cfg->channels,
          sizeof(struct p2p_channels));
      found = 1;
      break;
    }
  }

  if (found) {
    p2p_dbg(p2p,
      "Freq %d MHz is a common preferred channel for both peer and local, use it as operating channel",
      oper_freq);
  } else {
    p2p_dbg(p2p, "No common preferred channels found!");
  }
}


void p2p_check_pref_chan(struct p2p_data *p2p, int go,
       struct p2p_device *dev, struct p2p_message *msg)
{
  unsigned int size;
  unsigned int i;
  u8 op_class, op_channel;
  char txt[100], *pos, *end;
  bool is_6ghz_capab;
  int res;

  /*
   * Use the preferred channel list from the driver only if there is no
   * forced_freq, e.g., P2P_CONNECT freq=..., and no preferred operating
   * channel hardcoded in the configuration file.
   */
  if (!p2p->cfg->get_pref_freq_list || p2p->cfg->num_pref_chan ||
      (dev->flags & P2P_DEV_FORCE_FREQ) || p2p->cfg->cfg_op_channel)
    return;

  /* Obtain our preferred frequency list from driver based on P2P role. */
  size = ARRAY_SIZE(p2p->pref_freq_list);
  if (p2p->cfg->get_pref_freq_list(p2p->cfg->cb_ctx, go,
           &size,
           p2p->pref_freq_list))
    return;
  p2p->num_pref_freq = size;
  if (!size)
    return;
  /* Filter out frequencies that are not acceptable for P2P use */
  is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
    p2p_is_peer_6ghz_capab(p2p, dev->info.p2p_device_addr);
  i = 0;
  while (i < size) {
    bool is_dfs_freq;

    is_dfs_freq = p2p->cfg->is_p2p_dfs_chan(
      p2p->cfg->cb_ctx, p2p->pref_freq_list[i].freq, 0, 0);
    if (p2p_freq_to_channel(p2p->pref_freq_list[i].freq,
          &op_class, &op_channel) < 0 ||
        (!p2p_channels_includes(&p2p->cfg->channels,
              op_class, op_channel) &&
         (go || !p2p_channels_includes(&p2p->cfg->cli_channels,
               op_class, op_channel))) ||
        (is_6ghz_freq(p2p->pref_freq_list[i].freq) &&
         !is_6ghz_capab) ||
        (is_dfs_freq &&
         !is_dfs_freq_allowed(p2p, go,
            p2p->pref_freq_list[i].freq))) {
      p2p_dbg(p2p,
        "Ignore local driver frequency preference %u MHz since it is not acceptable for P2P use (go=%d)",
        p2p->pref_freq_list[i].freq, go);
      if (size - i - 1 > 0)
        os_memmove(&p2p->pref_freq_list[i],
             &p2p->pref_freq_list[i + 1],
             (size - i - 1) *
             sizeof(struct weighted_pcl));
      size--;
      continue;
    }

    /* Preferred frequency is acceptable for P2P use */
    i++;
  }

  pos = txt;
  end = pos + sizeof(txt);
  for (i = 0; i < size; i++) {
    res = os_snprintf(pos, end - pos, " %u",
          p2p->pref_freq_list[i].freq);
    if (os_snprintf_error(end - pos, res))
      break;
    pos += res;
  }
  *pos = '\0';
  p2p_dbg(p2p, "Local driver frequency preference (size=%u):%s",
    size, txt);

  /*
   * Check if peer's preference of operating channel is in
   * our preferred channel list.
   */
  for (i = 0; i < size; i++) {
    if (p2p->pref_freq_list[i].freq ==
        (unsigned int) dev->oper_freq &&
        p2p_pref_freq_allowed(&p2p->pref_freq_list[i], go))
      break;
  }
  if (i != size &&
      p2p_freq_to_channel(p2p->pref_freq_list[i].freq, &op_class,
        &op_channel) == 0) {
    /* Peer operating channel preference matches our preference */
    p2p->op_reg_class = op_class;
    p2p->op_channel = op_channel;
    os_memcpy(&p2p->channels, &p2p->cfg->channels,
        sizeof(struct p2p_channels));
    return;
  }

  p2p_dbg(p2p,
    "Peer operating channel preference: %d MHz is not in our preferred channel list",
    dev->oper_freq);

  /*
    Check if peer's preferred channel list is
    * _not_ included in the GO Negotiation Request or Invitation Request.
    */
  if (msg->pref_freq_list_len == 0)
    p2p_check_pref_chan_no_recv(p2p, go, dev, msg,
              p2p->pref_freq_list, size);
  else
    p2p_check_pref_chan_recv(p2p, go, dev, msg,
           p2p->pref_freq_list, size);
}


struct wpabuf * p2p_process_go_neg_req(struct p2p_data *p2p, const u8 *sa,
               const u8 *data, size_t len, int rx_freq,
               bool p2p2)
{
  struct p2p_device *dev = NULL;
  struct wpabuf *resp;
  struct p2p_message msg;
  u8 status = P2P_SC_FAIL_INVALID_PARAMS;
  int tie_breaker = 0;

  p2p_dbg(p2p, "Received GO Negotiation Request from " MACSTR "(freq=%d)",
    MAC2STR(sa), rx_freq);

  if (p2p_parse(data, len, &msg))
    return NULL;

  if (!msg.capability) {
    p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Request");
#ifdef CONFIG_P2P_STRICT
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  }

  if (msg.go_intent)
    tie_breaker = *msg.go_intent & 0x01;
  else {
    p2p_dbg(p2p, "Mandatory GO Intent attribute missing from GO Negotiation Request");
#ifdef CONFIG_P2P_STRICT
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  }

  if (!msg.config_timeout) {
    p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Request");
#ifdef CONFIG_P2P_STRICT
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  }

  if (!msg.listen_channel) {
    p2p_dbg(p2p, "No Listen Channel attribute received");
    goto fail;
  }
  if (!msg.operating_channel) {
    p2p_dbg(p2p, "No Operating Channel attribute received");
    goto fail;
  }
  if (!msg.channel_list) {
    p2p_dbg(p2p, "No Channel List attribute received");
    goto fail;
  }
  if (!msg.intended_addr) {
    p2p_dbg(p2p, "No Intended P2P Interface Address attribute received");
    goto fail;
  }
  if (!msg.p2p_device_info) {
    p2p_dbg(p2p, "No P2P Device Info attribute received");
    goto fail;
  }

  if (!ether_addr_equal(msg.p2p_device_addr, sa)) {
    p2p_dbg(p2p, "Unexpected GO Negotiation Request SA=" MACSTR
      " != dev_addr=" MACSTR,
      MAC2STR(sa), MAC2STR(msg.p2p_device_addr));
    goto fail;
  }

  dev = p2p_get_device(p2p, sa);

  if (msg.status && *msg.status) {
    p2p_dbg(p2p, "Unexpected Status attribute (%d) in GO Negotiation Request",
      *msg.status);
    if (dev && p2p->go_neg_peer == dev &&
        *msg.status == P2P_SC_FAIL_REJECTED_BY_USER) {
      /*
       * This mechanism for using Status attribute in GO
       * Negotiation Request is not compliant with the P2P
       * specification, but some deployed devices use it to
       * indicate rejection of GO Negotiation in a case where
       * they have sent out GO Negotiation Response with
       * status 1. The P2P specification explicitly disallows
       * this. To avoid unnecessary interoperability issues
       * and extra frames, mark the pending negotiation as
       * failed and do not reply to this GO Negotiation
       * Request frame.
       */
      p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
      p2p_go_neg_failed(p2p, *msg.status);
      p2p_parse_free(&msg);
      return NULL;
    }
    goto fail;
  }

  if (dev == NULL)
    dev = p2p_add_dev_from_go_neg_req(p2p, sa, &msg);
  else if ((dev->flags & P2P_DEV_PROBE_REQ_ONLY) ||
      !(dev->flags & P2P_DEV_REPORTED))
    p2p_add_dev_info(p2p, sa, dev, &msg);
  else if (!dev->listen_freq && !dev->oper_freq) {
    /*
     * This may happen if the peer entry was added based on PD
     * Request and no Probe Request/Response frame has been received
     * from this peer (or that information has timed out).
     */
    p2p_dbg(p2p, "Update peer " MACSTR
      " based on GO Neg Req since listen/oper freq not known",
      MAC2STR(dev->info.p2p_device_addr));
    p2p_add_dev_info(p2p, sa, dev, &msg);
  }

  if (dev)
    p2p_update_peer_6ghz_capab(dev, &msg);

  if (p2p->go_neg_peer && p2p->go_neg_peer == dev)
    eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);

  if (dev && dev->flags & P2P_DEV_USER_REJECTED) {
    p2p_dbg(p2p, "User has rejected this peer");
    status = P2P_SC_FAIL_REJECTED_BY_USER;
  } else if (dev == NULL ||
       (dev->wps_method == WPS_NOT_READY && !p2p2 &&
        (p2p->authorized_oob_dev_pw_id == 0 ||
         p2p->authorized_oob_dev_pw_id !=
         msg.dev_password_id))) {
    p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
      MAC2STR(sa));
    status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE;
    p2p->cfg->go_neg_req_rx(p2p->cfg->cb_ctx, sa,
          msg.dev_password_id,
          msg.go_intent ? (*msg.go_intent >> 1) :
          0);
  } else if (p2p->go_neg_peer && p2p->go_neg_peer != dev) {
    p2p_dbg(p2p, "Already in Group Formation with another peer");
    status = P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE;
  } else {
    int go;

    if (!p2p->go_neg_peer) {
      p2p_dbg(p2p, "Starting GO Negotiation with previously authorized peer");
      if (!(dev->flags & P2P_DEV_FORCE_FREQ)) {
        p2p_dbg(p2p, "Use default channel settings");
        p2p->op_reg_class = p2p->cfg->op_reg_class;
        p2p->op_channel = p2p->cfg->op_channel;
        os_memcpy(&p2p->channels, &p2p->cfg->channels,
            sizeof(struct p2p_channels));
      } else {
        p2p_dbg(p2p, "Use previously configured forced channel settings");
      }
    }

    dev->flags &= ~P2P_DEV_NOT_YET_READY;

    if (!msg.go_intent) {
      p2p_dbg(p2p, "No GO Intent attribute received");
      goto fail;
    }
    if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
      p2p_dbg(p2p, "Invalid GO Intent value (%u) received",
        *msg.go_intent >> 1);
      goto fail;
    }

    if (dev->go_neg_req_sent &&
        os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) > 0) {
      p2p_dbg(p2p, "Do not reply since peer has higher address and GO Neg Request already sent");
      p2p_parse_free(&msg);
      return NULL;
    }

    if (dev->go_neg_req_sent &&
        (dev->flags & P2P_DEV_PEER_WAITING_RESPONSE)) {
      p2p_dbg(p2p,
        "Do not reply since peer is waiting for us to start a new GO Negotiation and GO Neg Request already sent");
      p2p_parse_free(&msg);
      return NULL;
    }

    go = p2p_go_det(p2p->go_intent, *msg.go_intent);
    if (go < 0) {
      p2p_dbg(p2p, "Incompatible GO Intent");
      status = P2P_SC_FAIL_BOTH_GO_INTENT_15;
      goto fail;
    }

    if (p2p_peer_channels(p2p, dev, msg.channel_list,
              msg.channel_list_len) < 0) {
      p2p_dbg(p2p, "No common channels found");
      status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
      goto fail;
    }

    if (p2p2)
      goto skip;

    switch (msg.dev_password_id) {
    case DEV_PW_REGISTRAR_SPECIFIED:
      p2p_dbg(p2p, "PIN from peer Display");
      if (dev->wps_method != WPS_PIN_KEYPAD) {
        p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
          p2p_wps_method_str(dev->wps_method));
        status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
        goto fail;
      }
      break;
    case DEV_PW_USER_SPECIFIED:
      p2p_dbg(p2p, "Peer entered PIN on Keypad");
      if (dev->wps_method != WPS_PIN_DISPLAY) {
        p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
          p2p_wps_method_str(dev->wps_method));
        status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
        goto fail;
      }
      break;
    case DEV_PW_PUSHBUTTON:
      p2p_dbg(p2p, "Peer using pushbutton");
      if (dev->wps_method != WPS_PBC) {
        p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
          p2p_wps_method_str(dev->wps_method));
        status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
        goto fail;
      }
      break;
    case DEV_PW_P2PS_DEFAULT:
      p2p_dbg(p2p, "Peer using P2PS pin");
      if (dev->wps_method != WPS_P2PS) {
        p2p_dbg(p2p,
          "We have wps_method=%s -> incompatible",
          p2p_wps_method_str(dev->wps_method));
        status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
        goto fail;
      }
      break;
    default:
      if (msg.dev_password_id &&
          msg.dev_password_id == dev->oob_pw_id) {
        p2p_dbg(p2p, "Peer using NFC");
        if (dev->wps_method != WPS_NFC) {
          p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
            p2p_wps_method_str(
              dev->wps_method));
          status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
          goto fail;
        }
        break;
      }
#ifdef CONFIG_WPS_NFC
      if (p2p->authorized_oob_dev_pw_id &&
          msg.dev_password_id ==
          p2p->authorized_oob_dev_pw_id) {
        p2p_dbg(p2p, "Using static handover with our device password from NFC Tag");
        dev->wps_method = WPS_NFC;
        dev->oob_pw_id = p2p->authorized_oob_dev_pw_id;
        break;
      }
#endif /* CONFIG_WPS_NFC */
      p2p_dbg(p2p, "Unsupported Device Password ID %d",
        msg.dev_password_id);
      status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
      goto fail;
    }

skip:
    if (go && p2p_go_select_channel(p2p, dev, &status) < 0)
      goto fail;

    dev->go_state = go ? LOCAL_GO : REMOTE_GO;
    dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
                 msg.operating_channel[4]);
    p2p_dbg(p2p, "Peer operating channel preference: %d MHz",
      dev->oper_freq);

    /*
     * Use the driver preferred frequency list extension if
     * supported.
     */
    p2p_check_pref_chan(p2p, go, dev, &msg);

    if (msg.config_timeout) {
      dev->go_timeout = msg.config_timeout[0];
      dev->client_timeout = msg.config_timeout[1];
    }

    p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa));
    if (p2p->state != P2P_IDLE)
      p2p_stop_find_for_freq(p2p, rx_freq);
    p2p_set_state(p2p, P2P_GO_NEG);
    p2p_clear_timeout(p2p);
    dev->dialog_token = msg.dialog_token;
    os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);
    p2p->go_neg_peer = dev;
    eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);
    status = P2P_SC_SUCCESS;
  }

fail:
  if (dev)
    dev->status = status;
  resp = p2p_build_go_neg_resp(p2p, dev, msg.dialog_token, status,
             !tie_breaker);
  p2p_parse_free(&msg);
  if (resp == NULL)
    return NULL;

  if (status == P2P_SC_SUCCESS) {
    p2p->pending_action_state = P2P_PENDING_GO_NEG_RESPONSE;
    dev->flags |= P2P_DEV_WAIT_GO_NEG_CONFIRM;
    if (os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) < 0) {
      /*
       * Peer has smaller address, so the GO Negotiation
       * Response from us is expected to complete
       * negotiation. Ignore a GO Negotiation Response from
       * the peer if it happens to be received after this
       * point due to a race condition in GO Negotiation
       * Request transmission and processing.
       */
      dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
    }
  } else
    p2p->pending_action_state =
      P2P_PENDING_GO_NEG_RESPONSE_FAILURE;
  return resp;
}


void p2p_handle_go_neg_req(struct p2p_data *p2p, const u8 *sa, const u8 *data,
         size_t len, int rx_freq)
{
  int freq;
  struct wpabuf *resp;

  resp = p2p_process_go_neg_req(p2p, sa, data, len, rx_freq, false);
  if (!resp)
    return;

  p2p_dbg(p2p, "Sending GO Negotiation Response");

  if (rx_freq > 0)
    freq = rx_freq;
  else
    freq = p2p_channel_to_freq(p2p->cfg->reg_class,
             p2p->cfg->channel);
  if (freq < 0) {
    p2p_dbg(p2p, "Unknown regulatory class/channel");
    wpabuf_free(resp);
    return;
  }

  if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr,
          p2p->cfg->dev_addr,
          wpabuf_head(resp), wpabuf_len(resp), 100) < 0) {
    p2p_dbg(p2p, "Failed to send Action frame");
  }

  wpabuf_free(resp);
}


static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
               struct p2p_device *peer,
               u8 dialog_token, u8 status,
               const u8 *resp_chan, int go)
{
  struct wpabuf *buf;
  struct wpabuf *subelems;
  struct p2p_channels res;
  u8 group_capab;
  size_t extra = 0;
  bool is_6ghz_capab;

  p2p_dbg(p2p, "Building GO Negotiation Confirm");

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF])
    extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF]);

  buf = wpabuf_alloc(1000 + extra);
  if (buf == NULL)
    return NULL;

  p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_CONF, dialog_token);

  subelems = wpabuf_alloc(500);
  if (!subelems) {
    wpabuf_free(buf);
    return NULL;
  }

  p2p_buf_add_status(subelems, status);
  group_capab = 0;
  if (peer->go_state == LOCAL_GO) {
    if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
      group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
      if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
        group_capab |=
          P2P_GROUP_CAPAB_PERSISTENT_RECONN;
    }
    if (p2p->cross_connect)
      group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
    if (p2p->cfg->p2p_intra_bss)
      group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
  }
  p2p_buf_add_capability(subelems, p2p->dev_capab &
             ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
             group_capab);
  if (go || resp_chan == NULL)
    p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                p2p->op_reg_class,
                p2p->op_channel);
  else
    p2p_buf_add_operating_channel(subelems,
                (const char *) resp_chan,
                resp_chan[3], resp_chan[4]);
  p2p_channels_intersect(&p2p->channels, &peer->channels, &res);
  is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
    p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
  p2p_buf_add_channel_list(subelems, p2p->cfg->country, &res,
         is_6ghz_capab);
  if (go) {
    p2p_buf_add_group_id(subelems, p2p->cfg->dev_addr, p2p->ssid,
             p2p->ssid_len);
  }

#ifdef CONFIG_WIFI_DISPLAY
  if (p2p->wfd_ie_go_neg)
    wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */

  if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF])
    wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF]);

  buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
  wpabuf_free(subelems);
  return buf;
}


struct wpabuf * p2p_process_go_neg_resp(struct p2p_data *p2p, const u8 *sa,
          const u8 *data, size_t len,
          int rx_freq, bool p2p2)
{
  struct p2p_device *dev;
  int go = -1;
  struct p2p_message msg;
  u8 status = P2P_SC_SUCCESS;
  int freq;
  struct wpabuf *conf = NULL;

  p2p_dbg(p2p, "Received GO Negotiation Response from " MACSTR
    " (freq=%d)", MAC2STR(sa), rx_freq);
  dev = p2p_get_device(p2p, sa);
  if (dev == NULL || (!p2p2 && dev->wps_method == WPS_NOT_READY) ||
      dev != p2p->go_neg_peer) {
    p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
      MAC2STR(sa));
    return NULL;
  }

  if (p2p_parse(data, len, &msg))
    return NULL;

  if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_RESPONSE)) {
    p2p_dbg(p2p, "Was not expecting GO Negotiation Response - ignore");
    p2p_parse_free(&msg);
    return NULL;
  }
  dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
  p2p_update_peer_6ghz_capab(dev, &msg);

  if (msg.dialog_token != dev->dialog_token) {
    p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)",
      msg.dialog_token, dev->dialog_token);
    p2p_parse_free(&msg);
    return NULL;
  }

  if (!msg.status) {
    p2p_dbg(p2p, "No Status attribute received");
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }
  if (*msg.status) {
    p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status);
    dev->go_neg_req_sent = 0;
    if (*msg.status == P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE) {
      p2p_dbg(p2p, "Wait for the peer to become ready for GO Negotiation");
      dev->flags |= P2P_DEV_NOT_YET_READY;
      eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p,
               NULL);
      eloop_register_timeout(120, 0, p2p_go_neg_wait_timeout,
                 p2p, NULL);
      if (p2p->state == P2P_CONNECT_LISTEN)
        p2p_set_state(p2p, P2P_WAIT_PEER_CONNECT);
      else
        p2p_set_state(p2p, P2P_WAIT_PEER_IDLE);
      p2p_set_timeout(p2p, 0, 0);
    } else {
      p2p_dbg(p2p, "Stop GO Negotiation attempt");
      p2p_go_neg_failed(p2p, *msg.status);
    }
    p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
    p2p_parse_free(&msg);
    return NULL;
  }

  if (!msg.capability) {
    p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Response");
#ifdef CONFIG_P2P_STRICT
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  }

  if (!msg.p2p_device_info) {
    p2p_dbg(p2p, "Mandatory P2P Device Info attribute missing from GO Negotiation Response");
#ifdef CONFIG_P2P_STRICT
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  }

  if (!msg.intended_addr) {
    p2p_dbg(p2p, "No Intended P2P Interface Address attribute received");
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }

  if (!msg.go_intent) {
    p2p_dbg(p2p, "No GO Intent attribute received");
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }
  if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
    p2p_dbg(p2p, "Invalid GO Intent value (%u) received",
      *msg.go_intent >> 1);
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }

  go = p2p_go_det(p2p->go_intent, *msg.go_intent);
  if (go < 0) {
    p2p_dbg(p2p, "Incompatible GO Intent");
    status = P2P_SC_FAIL_INCOMPATIBLE_PARAMS;
    goto fail;
  }

  if (!go && msg.group_id) {
    /* Store SSID for Provisioning step */
    p2p->ssid_len = msg.group_id_len - ETH_ALEN;
    os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
  } else if (!go) {
    p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Response");
    p2p->ssid_len = 0;
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }

  if (!msg.config_timeout) {
    p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Response");
#ifdef CONFIG_P2P_STRICT
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
#endif /* CONFIG_P2P_STRICT */
  } else {
    dev->go_timeout = msg.config_timeout[0];
    dev->client_timeout = msg.config_timeout[1];
  }

  if (msg.wfd_subelems) {
    wpabuf_free(dev->info.wfd_subelems);
    dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems);
  }

  if (!msg.operating_channel && !go) {
    /*
     * Note: P2P Client may omit Operating Channel attribute to
     * indicate it does not have a preference.
     */
    p2p_dbg(p2p, "No Operating Channel attribute received");
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }
  if (!msg.channel_list) {
    p2p_dbg(p2p, "No Channel List attribute received");
    status = P2P_SC_FAIL_INVALID_PARAMS;
    goto fail;
  }

  if (p2p_peer_channels(p2p, dev, msg.channel_list,
            msg.channel_list_len) < 0) {
    p2p_dbg(p2p, "No common channels found");
    status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
    goto fail;
  }

  if (msg.operating_channel) {
    dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
                 msg.operating_channel[4]);
    p2p_dbg(p2p, "Peer operating channel preference: %d MHz",
      dev->oper_freq);
  } else
    dev->oper_freq = 0;

  if (p2p2)
    goto skip;

  switch (msg.dev_password_id) {
  case DEV_PW_REGISTRAR_SPECIFIED:
    p2p_dbg(p2p, "PIN from peer Display");
    if (dev->wps_method != WPS_PIN_KEYPAD) {
      p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
        p2p_wps_method_str(dev->wps_method));
      status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
      goto fail;
    }
    break;
  case DEV_PW_USER_SPECIFIED:
    p2p_dbg(p2p, "Peer entered PIN on Keypad");
    if (dev->wps_method != WPS_PIN_DISPLAY) {
      p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
        p2p_wps_method_str(dev->wps_method));
      status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
      goto fail;
    }
    break;
  case DEV_PW_PUSHBUTTON:
    p2p_dbg(p2p, "Peer using pushbutton");
    if (dev->wps_method != WPS_PBC) {
      p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
        p2p_wps_method_str(dev->wps_method));
      status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
      goto fail;
    }
    break;
  case DEV_PW_P2PS_DEFAULT:
    p2p_dbg(p2p, "P2P: Peer using P2PS default pin");
    if (dev->wps_method != WPS_P2PS) {
      p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
        p2p_wps_method_str(dev->wps_method));
      status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
      goto fail;
    }
    break;
  default:
    if (msg.dev_password_id &&
        msg.dev_password_id == dev->oob_pw_id) {
      p2p_dbg(p2p, "Peer using NFC");
      if (dev->wps_method != WPS_NFC) {
        p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
          p2p_wps_method_str(dev->wps_method));
        status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
        goto fail;
      }
      break;
    }
    p2p_dbg(p2p, "Unsupported Device Password ID %d",
      msg.dev_password_id);
    status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
    goto fail;
  }

skip:
  if (go && p2p_go_select_channel(p2p, dev, &status) < 0)
    goto fail;

  /*
   * Use the driver preferred frequency list extension if local device is
   * GO.
   */
  if (go)
    p2p_check_pref_chan(p2p, go, dev, &msg);

  p2p_set_state(p2p, P2P_GO_NEG);
  p2p_clear_timeout(p2p);

  p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa));
  os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);

fail:
  /* Store GO Negotiation Confirmation to allow retransmission */
  wpabuf_free(dev->go_neg_conf);
  dev->go_neg_conf = p2p_build_go_neg_conf(p2p, dev, msg.dialog_token,
             status, msg.operating_channel,
             go);
  p2p_parse_free(&msg);
  if (dev->go_neg_conf == NULL)
    return NULL;

  conf = wpabuf_dup(dev->go_neg_conf);

  if (status == P2P_SC_SUCCESS) {
    p2p->pending_action_state = P2P_PENDING_GO_NEG_CONFIRM;
    dev->go_state = go ? LOCAL_GO : REMOTE_GO;
  } else
    p2p->pending_action_state = P2P_NO_PENDING_ACTION;
  if (rx_freq > 0)
    freq = rx_freq;
  else
    freq = dev->listen_freq;

  dev->go_neg_conf_freq = freq;
  dev->go_neg_conf_sent = 0;

  if (status != P2P_SC_SUCCESS) {
    p2p_dbg(p2p, "GO Negotiation failed");
    dev->status = status;
  }

  return conf;
}


void p2p_handle_go_neg_resp(struct p2p_data *p2p, const u8 *sa, const u8 *data,
          size_t len, int rx_freq)
{
  int freq;
  struct p2p_device *dev;
  struct wpabuf *conf;

  conf = p2p_process_go_neg_resp(p2p, sa, data, len, rx_freq, false);
  if (!conf)
    return;
  wpabuf_free(conf);

  dev = p2p_get_device(p2p, sa);
  if (!dev)
    return;

  p2p_dbg(p2p, "Sending GO Negotiation Confirm");
  if (rx_freq > 0)
    freq = rx_freq;
  else
    freq = dev->listen_freq;

  if (dev->go_neg_conf &&
      p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, sa,
          wpabuf_head(dev->go_neg_conf),
          wpabuf_len(dev->go_neg_conf), 50) < 0) {
    p2p_dbg(p2p, "Failed to send Action frame");
    p2p_go_neg_failed(p2p, -1);
    p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
  } else
    dev->go_neg_conf_sent++;

  if (dev->status != P2P_SC_SUCCESS)
    p2p_go_neg_failed(p2p, dev->status);
}


void p2p_handle_go_neg_conf(struct p2p_data *p2p, const u8 *sa,
          const u8 *data, size_t len, bool p2p2)
{
  struct p2p_device *dev;
  struct p2p_message msg;

  p2p_dbg(p2p, "Received GO Negotiation Confirm from " MACSTR,
    MAC2STR(sa));
  dev = p2p_get_device(p2p, sa);
  if (dev == NULL || (!p2p2 && dev->wps_method == WPS_NOT_READY) ||
      dev != p2p->go_neg_peer) {
    p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
      MAC2STR(sa));
    return;
  }

  if (p2p->pending_action_state == P2P_PENDING_GO_NEG_RESPONSE) {
    p2p_dbg(p2p, "Stopped waiting for TX status on GO Negotiation Response since we already received Confirmation");
    p2p->pending_action_state = P2P_NO_PENDING_ACTION;
  }

  if (p2p_parse(data, len, &msg))
    return;

  if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_CONFIRM)) {
    p2p_dbg(p2p, "Was not expecting GO Negotiation Confirm - ignore");
    p2p_parse_free(&msg);
    return;
  }
  dev->flags &= ~P2P_DEV_WAIT_GO_NEG_CONFIRM;
  p2p->cfg->send_action_done(p2p->cfg->cb_ctx);

  if (msg.dialog_token != dev->dialog_token) {
    p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)",
      msg.dialog_token, dev->dialog_token);
    p2p_parse_free(&msg);
    return;
  }

  if (!msg.status) {
    p2p_dbg(p2p, "No Status attribute received");
    p2p_parse_free(&msg);
    return;
  }
  if (*msg.status) {
    p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status);
    p2p_go_neg_failed(p2p, *msg.status);
    p2p_parse_free(&msg);
    return;
  }

  p2p_update_peer_6ghz_capab(dev, &msg);

  if (dev->go_state == REMOTE_GO && msg.group_id) {
    /* Store SSID for Provisioning step */
    p2p->ssid_len = msg.group_id_len - ETH_ALEN;
    os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
  } else if (dev->go_state == REMOTE_GO) {
    p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Confirmation");
    p2p->ssid_len = 0;
    p2p_go_neg_failed(p2p, P2P_SC_FAIL_INVALID_PARAMS);
    p2p_parse_free(&msg);
    return;
  }

  if (!msg.operating_channel) {
    p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation");
#ifdef CONFIG_P2P_STRICT
    p2p_parse_free(&msg);
    return;
#endif /* CONFIG_P2P_STRICT */
  } else if (dev->go_state == REMOTE_GO) {
    int oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
                msg.operating_channel[4]);
    if (oper_freq != dev->oper_freq) {
      p2p_dbg(p2p, "Updated peer (GO) operating channel preference from %d MHz to %d MHz",
        dev->oper_freq, oper_freq);
      dev->oper_freq = oper_freq;
    }
  }

  if (!msg.channel_list) {
    p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation");
#ifdef CONFIG_P2P_STRICT
    p2p_parse_free(&msg);
    return;
#endif /* CONFIG_P2P_STRICT */
  }

  p2p_parse_free(&msg);

  if (dev->go_state == UNKNOWN_GO) {
    /*
     * This should not happen since GO negotiation has already
     * been completed.
     */
    p2p_dbg(p2p, "Unexpected GO Neg state - do not know which end becomes GO");
    return;
  }

  /*
   * The peer could have missed our ctrl::ack frame for GO Negotiation
   * Confirm and continue retransmitting the frame. To reduce the
   * likelihood of the peer not getting successful TX status for the
   * GO Negotiation Confirm frame, wait a short time here before starting
   * the group so that we will remain on the current channel to
   * acknowledge any possible retransmission from the peer.
   */
  p2p_dbg(p2p, "20 ms wait on current channel before starting group");
  os_sleep(0, 20000);

  p2p_go_complete(p2p, dev);
}

Coverage Report

Created: 2026-04-12 06:28