/*

 * Generic advertisement service (GAS) query

 * Copyright (c) 2009, Atheros Communications

 * Copyright (c) 2011-2014, Qualcomm Atheros, Inc.

 * Copyright (c) 2011-2014, Jouni Malinen <j@w1.fi>

 *

 * 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/gas.h"

#include "common/wpa_ctrl.h"

#include "rsn_supp/wpa.h"

#include "wpa_supplicant_i.h"

#include "config.h"

#include "driver_i.h"

#include "offchannel.h"

#include "gas_query.h"

/** GAS query timeout in seconds */

#define GAS_QUERY_TIMEOUT_PERIOD 2

/* GAS query wait-time / duration in ms */

#define GAS_QUERY_WAIT_TIME_INITIAL 1000

#define GAS_QUERY_WAIT_TIME_COMEBACK 150

#define GAS_QUERY_MAX_COMEBACK_DELAY 60000

/**

 * struct gas_query_pending - Pending GAS query

 */

struct gas_query_pending {

  struct dl_list list;

  struct gas_query *gas;

  struct wpa_radio_work *work;

  u8 addr[ETH_ALEN];

  u8 dialog_token;

  u8 next_frag_id;

  unsigned int wait_comeback:1;

  unsigned int offchannel_tx_started:1;

  unsigned int retry:1;

  unsigned int wildcard_bssid:1;

  unsigned int maintain_addr:1;

  unsigned int sent:1;

  int freq;

  u16 status_code;

  struct wpabuf *req;

  struct wpabuf *adv_proto;

  struct wpabuf *resp;

  struct os_reltime last_oper;

  void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,

       enum gas_query_result result,

       const struct wpabuf *adv_proto,

       const struct wpabuf *resp, u16 status_code);

  void *ctx;

  u8 sa[ETH_ALEN];

};

/**

 * struct gas_query - Internal GAS query data

 */

struct gas_query {

  struct wpa_supplicant *wpa_s;

  struct dl_list pending; /* struct gas_query_pending */

  struct gas_query_pending *current;

  struct os_reltime last_mac_addr_rand;

  int last_rand_sa_type;

  u8 rand_addr[ETH_ALEN];

};

static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);

static void gas_query_timeout(void *eloop_data, void *user_ctx);

static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx);

static void gas_query_tx_initial_req(struct gas_query *gas,

             struct gas_query_pending *query);

static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst);

static int ms_from_time(struct os_reltime *last)

{

  struct os_reltime now, res;

  os_get_reltime(&now);

  os_reltime_sub(&now, last, &res);

  return res.sec * 1000 + res.usec / 1000;

}

/**

 * gas_query_init - Initialize GAS query component

 * @wpa_s: Pointer to wpa_supplicant data

 * Returns: Pointer to GAS query data or %NULL on failure

 */

struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)

{

  struct gas_query *gas;

  gas = os_zalloc(sizeof(*gas));

  if (gas == NULL)

    return NULL;

  gas->wpa_s = wpa_s;

  dl_list_init(&gas->pending);

  return gas;

}

static const char * gas_result_txt(enum gas_query_result result)

{

  switch (result) {

  case GAS_QUERY_SUCCESS:

    return "SUCCESS";

  case GAS_QUERY_FAILURE:

    return "FAILURE";

  case GAS_QUERY_TIMEOUT:

    return "TIMEOUT";

  case GAS_QUERY_PEER_ERROR:

    return "PEER_ERROR";

  case GAS_QUERY_INTERNAL_ERROR:

    return "INTERNAL_ERROR";

  case GAS_QUERY_STOPPED:

    return "STOPPED";

  case GAS_QUERY_DELETED_AT_DEINIT:

    return "DELETED_AT_DEINIT";

  }

  return "N/A";

}

static void gas_query_free(struct gas_query_pending *query, int del_list)

{

  struct gas_query *gas = query->gas;

  if (del_list)

    dl_list_del(&query->list);

  if (gas->current == query)

    gas->current = NULL;

  if (query->work)

    radio_work_done(query->work);

  eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);

  eloop_cancel_timeout(gas_query_timeout, gas, query);

  eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);

  wpabuf_free(query->req);

  wpabuf_free(query->adv_proto);

  wpabuf_free(query->resp);

  os_free(query);

}

static void gas_query_done(struct gas_query *gas,

         struct gas_query_pending *query,

         enum gas_query_result result)

{

  wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR

    " dialog_token=%u freq=%d status_code=%u result=%s",

    MAC2STR(query->addr), query->dialog_token, query->freq,

    query->status_code, gas_result_txt(result));

  if (query->offchannel_tx_started)

    offchannel_send_action_done(gas->wpa_s);

  dl_list_del(&query->list);

  query->cb(query->ctx, query->addr, query->dialog_token, result,

      query->adv_proto, query->resp, query->status_code);

  gas_query_free(query, 0);

}

/**

 * gas_query_deinit - Deinitialize GAS query component

 * @gas: GAS query data from gas_query_init()

 */

void gas_query_deinit(struct gas_query *gas)

{

  struct gas_query_pending *query, *next;

  if (gas == NULL)

    return;

  dl_list_for_each_safe(query, next, &gas->pending,

            struct gas_query_pending, list)

    gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);

  os_free(gas);

}

static struct gas_query_pending *

gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)

{

  struct gas_query_pending *q, *alt = NULL;

  struct wpa_supplicant *wpa_s = gas->wpa_s;

  /* Prefer a pending entry that matches with the current radio_work to

   * avoid issues when freeing the pending entry in gas_query_free(). That

   * case should not really happen, but due to the special case for

   * AP MLD MAC address here, a same dialog token value might end up

   * being pending and matching the same query. */

  dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {

    if (!q->sent)

      continue;

    if ((ether_addr_equal(q->addr, addr) &&

         q->dialog_token == dialog_token) ||

        (wpa_s->valid_links &&

         ether_addr_equal(wpa_s->ap_mld_addr, addr) &&

         wpas_ap_link_address(wpa_s, q->addr))) {

      if (q == gas->current)

        return q;

      if (!alt)

        alt = q;

    }

  }

  return alt;

}

static int gas_query_append(struct gas_query_pending *query, const u8 *data,

          size_t len)

{

  if (wpabuf_resize(&query->resp, len) < 0) {

    wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");

    return -1;

  }

  wpabuf_put_data(query->resp, data, len);

  return 0;

}

static void gas_query_tx_status(struct wpa_supplicant *wpa_s,

        unsigned int freq, const u8 *dst,

        const u8 *src, const u8 *bssid,

        const u8 *data, size_t data_len,

        enum offchannel_send_action_result result)

{

  struct gas_query_pending *query;

  struct gas_query *gas = wpa_s->gas;

  int dur;

  if (gas->current == NULL) {

    wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst="

         MACSTR " result=%d - no query in progress",

         freq, MAC2STR(dst), result);

    return;

  }

  query = gas->current;

  dur = ms_from_time(&query->last_oper);

  wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR

       " result=%d query=%p dialog_token=%u dur=%d ms",

       freq, MAC2STR(dst), result, query, query->dialog_token, dur);

  if (!ether_addr_equal(dst, query->addr)) {

    wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");

    return;

  }

  os_get_reltime(&query->last_oper);

  if (result == OFFCHANNEL_SEND_ACTION_SUCCESS ||

      result == OFFCHANNEL_SEND_ACTION_NO_ACK) {

    eloop_cancel_timeout(gas_query_timeout, gas, query);

    if (result == OFFCHANNEL_SEND_ACTION_NO_ACK) {

      wpa_printf(MSG_DEBUG, "GAS: No ACK to GAS request");

      eloop_register_timeout(0, 250000,

                 gas_query_timeout, gas, query);

    } else {

      eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,

                 gas_query_timeout, gas, query);

    }

    if (query->wait_comeback && !query->retry) {

      eloop_cancel_timeout(gas_query_rx_comeback_timeout,

               gas, query);

      eloop_register_timeout(

        0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000,

        gas_query_rx_comeback_timeout, gas, query);

    }

  }

  if (result == OFFCHANNEL_SEND_ACTION_FAILED) {

    eloop_cancel_timeout(gas_query_timeout, gas, query);

    eloop_register_timeout(0, 0, gas_query_timeout, gas, query);

  }

}

static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,

      struct wpabuf *req, unsigned int wait_time)

{

  int res, prot = pmf_in_use(gas->wpa_s, query->addr);

  const u8 *bssid;

  const u8 wildcard_bssid[ETH_ALEN] = {

    0xff, 0xff, 0xff, 0xff, 0xff, 0xff

  };

  wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "

       "freq=%d prot=%d using src addr " MACSTR,

       MAC2STR(query->addr), (unsigned int) wpabuf_len(req),

       query->freq, prot, MAC2STR(query->sa));

  if (prot) {

    u8 *categ = wpabuf_mhead_u8(req);

    *categ = WLAN_ACTION_PROTECTED_DUAL;

  }

  os_get_reltime(&query->last_oper);

  if (gas->wpa_s->max_remain_on_chan &&

      wait_time > gas->wpa_s->max_remain_on_chan)

    wait_time = gas->wpa_s->max_remain_on_chan;

  if (!query->wildcard_bssid &&

      (!gas->wpa_s->conf->gas_address3 ||

       (gas->wpa_s->current_ssid &&

        gas->wpa_s->wpa_state >= WPA_ASSOCIATED &&

        ether_addr_equal(query->addr, gas->wpa_s->bssid))))

    bssid = query->addr;

  else

    bssid = wildcard_bssid;

  res = offchannel_send_action(gas->wpa_s, query->freq, query->addr,

             query->sa, bssid, wpabuf_head(req),

             wpabuf_len(req), wait_time,

             gas_query_tx_status, 0);

  if (res == 0) {

    query->sent = 1;

    query->offchannel_tx_started = 1;

  }

  return res;

}

static void gas_query_tx_comeback_req(struct gas_query *gas,

              struct gas_query_pending *query)

{

  struct wpabuf *req;

  unsigned int wait_time;

  req = gas_build_comeback_req(query->dialog_token);

  if (req == NULL) {

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

    return;

  }

  wait_time = (query->retry || !query->offchannel_tx_started) ?

    GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK;

  if (gas_query_tx(gas, query, req, wait_time) < 0) {

    wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "

         MACSTR, MAC2STR(query->addr));

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

  }

  wpabuf_free(req);

}

static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx)

{

  struct gas_query *gas = eloop_data;

  struct gas_query_pending *query = user_ctx;

  int dialog_token;

  wpa_printf(MSG_DEBUG,

       "GAS: No response to comeback request received (retry=%u)",

       query->retry);

  if (gas->current != query || query->retry)

    return;

  dialog_token = gas_query_new_dialog_token(gas, query->addr);

  if (dialog_token < 0)

    return;

  wpa_printf(MSG_DEBUG,

       "GAS: Retry GAS query due to comeback response timeout");

  query->retry = 1;

  query->dialog_token = dialog_token;

  *(wpabuf_mhead_u8(query->req) + 2) = dialog_token;

  query->wait_comeback = 0;

  query->next_frag_id = 0;

  wpabuf_free(query->adv_proto);

  query->adv_proto = NULL;

  eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);

  eloop_cancel_timeout(gas_query_timeout, gas, query);

  gas_query_tx_initial_req(gas, query);

}

static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)

{

  struct gas_query *gas = eloop_data;

  struct gas_query_pending *query = user_ctx;

  wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,

       MAC2STR(query->addr));

  gas_query_tx_comeback_req(gas, query);

}

static void gas_query_tx_comeback_req_delay(struct gas_query *gas,

              struct gas_query_pending *query,

              u16 comeback_delay)

{

  unsigned int secs, usecs;

  if (comeback_delay > 1 && query->offchannel_tx_started) {

    offchannel_send_action_done(gas->wpa_s);

    query->offchannel_tx_started = 0;

  }

  secs = (comeback_delay * 1024) / 1000000;

  usecs = comeback_delay * 1024 - secs * 1000000;

  wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR

       " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);

  eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);

  eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,

             gas, query);

}

static void gas_query_rx_initial(struct gas_query *gas,

         struct gas_query_pending *query,

         const u8 *adv_proto, size_t adv_proto_len,

         const u8 *resp, size_t len, u16 comeback_delay)

{

  wpa_printf(MSG_DEBUG, "GAS: Received initial response from "

       MACSTR " (dialog_token=%u comeback_delay=%u)",

       MAC2STR(query->addr), query->dialog_token, comeback_delay);

  query->adv_proto = wpabuf_alloc_copy(adv_proto, adv_proto_len);

  if (query->adv_proto == NULL) {

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

    return;

  }

  if (comeback_delay) {

    eloop_cancel_timeout(gas_query_timeout, gas, query);

    query->wait_comeback = 1;

    gas_query_tx_comeback_req_delay(gas, query, comeback_delay);

    return;

  }

  /* Query was completed without comeback mechanism */

  if (gas_query_append(query, resp, len) < 0) {

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

    return;

  }

  gas_query_done(gas, query, GAS_QUERY_SUCCESS);

}

static void gas_query_rx_comeback(struct gas_query *gas,

          struct gas_query_pending *query,

          const u8 *adv_proto, size_t adv_proto_len,

          const u8 *resp, size_t len, u8 frag_id,

          u8 more_frags, u16 comeback_delay)

{

  wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "

       MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "

       "comeback_delay=%u)",

       MAC2STR(query->addr), query->dialog_token, frag_id,

       more_frags, comeback_delay);

  eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);

  if (adv_proto_len != wpabuf_len(query->adv_proto) ||

      os_memcmp(adv_proto, wpabuf_head(query->adv_proto),

          wpabuf_len(query->adv_proto)) != 0) {

    wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "

         "between initial and comeback response from "

         MACSTR, MAC2STR(query->addr));

    gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);

    return;

  }

  if (comeback_delay) {

    if (frag_id) {

      wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "

           "with non-zero frag_id and comeback_delay "

           "from " MACSTR, MAC2STR(query->addr));

      gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);

      return;

    }

    gas_query_tx_comeback_req_delay(gas, query, comeback_delay);

    return;

  }

  if (frag_id != query->next_frag_id) {

    wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "

         "from " MACSTR, MAC2STR(query->addr));

    if (frag_id + 1 == query->next_frag_id) {

      wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "

           "retry of previous fragment");

      return;

    }

    gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);

    return;

  }

  query->next_frag_id++;

  if (gas_query_append(query, resp, len) < 0) {

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

    return;

  }

  if (more_frags) {

    gas_query_tx_comeback_req(gas, query);

    return;

  }

  gas_query_done(gas, query, GAS_QUERY_SUCCESS);

}

/**

 * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame

 * @gas: GAS query data from gas_query_init()

 * @da: Destination MAC address of the Action frame

 * @sa: Source MAC address of the Action frame

 * @bssid: BSSID of the Action frame

 * @categ: Category of the Action frame

 * @data: Payload of the Action frame

 * @len: Length of @data

 * @freq: Frequency (in MHz) on which the frame was received

 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not

 */

int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,

     const u8 *bssid, u8 categ, const u8 *data, size_t len,

     int freq)

{

  struct gas_query_pending *query;

  u8 action, dialog_token, frag_id = 0, more_frags = 0;

  u16 comeback_delay, resp_len;

  const u8 *pos, *adv_proto;

  size_t adv_proto_len;

  int prot, pmf;

  unsigned int left;

  if (gas == NULL || len < 4)

    return -1;

  pos = data;

  action = *pos++;

  dialog_token = *pos++;

  if (action != WLAN_PA_GAS_INITIAL_RESP &&

      action != WLAN_PA_GAS_COMEBACK_RESP)

    return -1; /* Not a GAS response */

  prot = categ == WLAN_ACTION_PROTECTED_DUAL;

  pmf = pmf_in_use(gas->wpa_s, sa);

  if (prot && !pmf) {

    wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled");

    return 0;

  }

  if (!prot && pmf) {

    wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled");

    return 0;

  }

  if (pmf && is_multicast_ether_addr(da)) {

    wpa_printf(MSG_DEBUG,

         "GAS: Ignore group-addressed GAS frame (A1=" MACSTR

         " A2=" MACSTR ") when PMF is enabled",

         MAC2STR(da), MAC2STR(sa));

    return 0;

  }

  query = gas_query_get_pending(gas, sa, dialog_token);

  if (query == NULL) {

    wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR

         " dialog token %u", MAC2STR(sa), dialog_token);

    return -1;

  }

  wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR,

       ms_from_time(&query->last_oper), MAC2STR(sa));

  if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {

    wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "

         MACSTR " dialog token %u when waiting for comeback "

         "response", MAC2STR(sa), dialog_token);

    return 0;

  }

  if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {

    wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "

         MACSTR " dialog token %u when waiting for initial "

         "response", MAC2STR(sa), dialog_token);

    return 0;

  }

  query->status_code = WPA_GET_LE16(pos);

  pos += 2;

  if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING &&

      action == WLAN_PA_GAS_COMEBACK_RESP) {

    wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response");

  } else if (query->status_code != WLAN_STATUS_SUCCESS) {

    wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "

         "%u failed - status code %u",

         MAC2STR(sa), dialog_token, query->status_code);

    gas_query_done(gas, query, GAS_QUERY_FAILURE);

    return 0;

  }

  if (action == WLAN_PA_GAS_COMEBACK_RESP) {

    if (pos + 1 > data + len)

      return 0;

    frag_id = *pos & 0x7f;

    more_frags = (*pos & 0x80) >> 7;

    pos++;

  }

  /* Comeback Delay */

  if (pos + 2 > data + len)

    return 0;

  comeback_delay = WPA_GET_LE16(pos);

  if (comeback_delay > GAS_QUERY_MAX_COMEBACK_DELAY)

    comeback_delay = GAS_QUERY_MAX_COMEBACK_DELAY;

  pos += 2;

  /* Advertisement Protocol element */

  adv_proto = pos;

  left = data + len - adv_proto;

  if (left < 2 || adv_proto[1] > left - 2) {

    wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "

         "Protocol element in the response from " MACSTR,

         MAC2STR(sa));

    return 0;

  }

  if (*adv_proto != WLAN_EID_ADV_PROTO) {

    wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "

         "Protocol element ID %u in response from " MACSTR,

         *adv_proto, MAC2STR(sa));

    return 0;

  }

  adv_proto_len = 2 + adv_proto[1];

  if (adv_proto_len > (size_t) (data + len - pos))

    return 0; /* unreachable due to an earlier check */

  pos += adv_proto_len;

  /* Query Response Length */

  if (pos + 2 > data + len) {

    wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");

    return 0;

  }

  resp_len = WPA_GET_LE16(pos);

  pos += 2;

  left = data + len - pos;

  if (resp_len > left) {

    wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "

         "response from " MACSTR, MAC2STR(sa));

    return 0;

  }

  if (resp_len < left) {

    wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "

         "after Query Response from " MACSTR,

         left - resp_len, MAC2STR(sa));

  }

  if (action == WLAN_PA_GAS_COMEBACK_RESP)

    gas_query_rx_comeback(gas, query, adv_proto, adv_proto_len,

              pos, resp_len, frag_id, more_frags,

              comeback_delay);

  else

    gas_query_rx_initial(gas, query, adv_proto, adv_proto_len,

             pos, resp_len, comeback_delay);

  return 0;

}

static void gas_query_timeout(void *eloop_data, void *user_ctx)

{

  struct gas_query *gas = eloop_data;

  struct gas_query_pending *query = user_ctx;

  wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR

       " dialog token %u",

       MAC2STR(query->addr), query->dialog_token);

  gas_query_done(gas, query, GAS_QUERY_TIMEOUT);

}

static int gas_query_dialog_token_available(struct gas_query *gas,

              const u8 *dst, u8 dialog_token)

{

  struct gas_query_pending *q;

  dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {

    if ((!dst || ether_addr_equal(dst, q->addr)) &&

        dialog_token == q->dialog_token)

      return 0;

  }

  return 1;

}

static void gas_query_start_cb(struct wpa_radio_work *work, int deinit)

{

  struct gas_query_pending *query = work->ctx;

  struct gas_query *gas = query->gas;

  struct wpa_supplicant *wpa_s = gas->wpa_s;

  if (deinit) {

    if (work->started) {

      gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);

      return;

    }

    gas_query_free(query, 1);

    return;

  }

  if (!query->maintain_addr && !wpa_s->conf->gas_rand_mac_addr) {

    if (wpas_update_random_addr_disassoc(wpa_s) < 0) {

      wpa_msg(wpa_s, MSG_INFO,

        "Failed to assign random MAC address for GAS");

      gas_query_free(query, 1);

      return;

    }

    os_memcpy(query->sa, wpa_s->own_addr, ETH_ALEN);

  }

  gas_query_tx_initial_req(gas, query);

}

static void gas_query_tx_initial_req(struct gas_query *gas,

             struct gas_query_pending *query)

{

  if (gas_query_tx(gas, query, query->req,

       GAS_QUERY_WAIT_TIME_INITIAL) < 0) {

    wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "

         MACSTR, MAC2STR(query->addr));

    gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);

    return;

  }

  gas->current = query;

  wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",

       query->dialog_token);

  eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,

             gas_query_timeout, gas, query);

}

static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst)

{

  u8 dialog_token;

  int i;

  /* There should never be more than couple active GAS queries in

   * progress, so it should be very likely to find an available dialog

   * token by checking random values. Use a limit on the number of

   * iterations to handle the unexpected case of large number of pending

   * queries cleanly. */

  for (i = 0; i < 256; i++) {

    /* Get a random number and check if it is not used in any

     * pending entry for any peer. */

    if (os_get_random(&dialog_token, sizeof(dialog_token)) < 0)

      break;

    if (gas_query_dialog_token_available(gas, NULL, dialog_token))

      return dialog_token;

  }

  /* In the highly unlikely case there were so many pending queries that

   * no available unused dialog token was available. Try to find one that

   * is unique for this specific peer. */

  for (i = 0; i < 256; i++) {

    /* Get a random number and check if the slot is available */

    if (os_get_random(&dialog_token, sizeof(dialog_token)) < 0)

      break;

    if (gas_query_dialog_token_available(gas, dst, dialog_token))

      return dialog_token;

  }

  /* No dialog token value available */

  return -1;

}

static int gas_query_set_sa(struct gas_query *gas,

          struct gas_query_pending *query)

{

  struct wpa_supplicant *wpa_s = gas->wpa_s;

  struct os_reltime now;

  if (query->maintain_addr ||

      !wpa_s->conf->gas_rand_mac_addr ||

      !(wpa_s->current_bss ?

        (wpa_s->drv_flags &

         WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA_CONNECTED) :

        (wpa_s->drv_flags & WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA))) {

    /* Use own MAC address as the transmitter address */

    wpa_printf(MSG_DEBUG,

         "GAS: Use own MAC address as the transmitter address%s%s%s",

         query->maintain_addr ? " (maintain_addr)" : "",

         !wpa_s->conf->gas_rand_mac_addr ? " (no gas_rand_mac_adr set)" : "",

         !(wpa_s->current_bss ?

           (wpa_s->drv_flags &

            WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA_CONNECTED) :

           (wpa_s->drv_flags &

            WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA)) ?

         " (no driver rand capa" : "");

    os_memcpy(query->sa, wpa_s->own_addr, ETH_ALEN);

    return 0;

  }

  os_get_reltime(&now);

  if (wpa_s->conf->gas_rand_mac_addr == gas->last_rand_sa_type &&

      gas->last_mac_addr_rand.sec != 0 &&

      !os_reltime_expired(&now, &gas->last_mac_addr_rand,

        wpa_s->conf->gas_rand_addr_lifetime)) {

    wpa_printf(MSG_DEBUG,

         "GAS: Use the previously selected random transmitter address "

         MACSTR, MAC2STR(gas->rand_addr));

    os_memcpy(query->sa, gas->rand_addr, ETH_ALEN);

    return 0;

  }

  if (wpa_s->conf->gas_rand_mac_addr == 1 &&

      random_mac_addr(gas->rand_addr) < 0) {

    wpa_printf(MSG_ERROR, "GAS: Failed to get random address");

    return -1;

  }

  if (wpa_s->conf->gas_rand_mac_addr == 2 &&

      random_mac_addr_keep_oui(gas->rand_addr) < 0) {

    wpa_printf(MSG_ERROR,

         "GAS: Failed to get random address with same OUI");

    return -1;

  }

  wpa_printf(MSG_DEBUG, "GAS: Use a new random transmitter address "

       MACSTR, MAC2STR(gas->rand_addr));

  os_memcpy(query->sa, gas->rand_addr, ETH_ALEN);

  os_get_reltime(&gas->last_mac_addr_rand);

  gas->last_rand_sa_type = wpa_s->conf->gas_rand_mac_addr;

  return 0;

}

/**

 * gas_query_req - Request a GAS query

 * @gas: GAS query data from gas_query_init()

 * @dst: Destination MAC address for the query

 * @freq: Frequency (in MHz) for the channel on which to send the query

 * @wildcard_bssid: Force use of wildcard BSSID value

 * @maintain_addr: Maintain own MAC address for exchange (i.e., ignore MAC

 *  address randomization rules)

 * @req: GAS query payload (to be freed by gas_query module in case of success

 *  return)

 * @cb: Callback function for reporting GAS query result and response

 * @ctx: Context pointer to use with the @cb call

 * Returns: dialog token (>= 0) on success or -1 on failure

 */

int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,

      int wildcard_bssid, int maintain_addr, struct wpabuf *req,

      void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,

           enum gas_query_result result,

           const struct wpabuf *adv_proto,

           const struct wpabuf *resp, u16 status_code),

      void *ctx)

{

  struct gas_query_pending *query;

  int dialog_token;

  if (wpabuf_len(req) < 3)

    return -1;

  dialog_token = gas_query_new_dialog_token(gas, dst);

  if (dialog_token < 0)

    return -1;

  query = os_zalloc(sizeof(*query));

  if (query == NULL)

    return -1;

  query->gas = gas;