/*

 * hostapd / IEEE 802.11n HT

 * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>

 * Copyright (c) 2007-2008, Intel Corporation

 *

 * This software may be distributed under the terms of the BSD license.

 * See README for more details.

 */

#include "utils/includes.h"

#include "utils/common.h"

#include "utils/eloop.h"

#include "common/ieee802_11_defs.h"

#include "hostapd.h"

#include "ap_config.h"

#include "sta_info.h"

#include "beacon.h"

#include "ieee802_11.h"

#include "hw_features.h"

#include "ap_drv_ops.h"

u8 * hostapd_eid_ht_capabilities(struct hostapd_data *hapd, u8 *eid)

{

  struct ieee80211_ht_capabilities *cap;

  u8 *pos = eid;

  if (!hapd->iconf->ieee80211n || !hapd->iface->current_mode ||

      hapd->conf->disable_11n || is_6ghz_op_class(hapd->iconf->op_class))

    return eid;

  *pos++ = WLAN_EID_HT_CAP;

  *pos++ = sizeof(*cap);

  cap = (struct ieee80211_ht_capabilities *) pos;

  os_memset(cap, 0, sizeof(*cap));

  cap->ht_capabilities_info = host_to_le16(hapd->iconf->ht_capab);

  cap->a_mpdu_params = hapd->iface->current_mode->a_mpdu_params;

  os_memcpy(cap->supported_mcs_set, hapd->iface->current_mode->mcs_set,

      16);

  /* TODO: ht_extended_capabilities (now fully disabled) */

  /* TODO: tx_bf_capability_info (now fully disabled) */

  /* TODO: asel_capabilities (now fully disabled) */

  pos += sizeof(*cap);

  if (hapd->iconf->obss_interval) {

    struct ieee80211_obss_scan_parameters *scan_params;

    *pos++ = WLAN_EID_OVERLAPPING_BSS_SCAN_PARAMS;

    *pos++ = sizeof(*scan_params);

    scan_params = (struct ieee80211_obss_scan_parameters *) pos;

    os_memset(scan_params, 0, sizeof(*scan_params));

    scan_params->width_trigger_scan_interval =

      host_to_le16(hapd->iconf->obss_interval);

    /* Fill in default values for remaining parameters

     * (IEEE Std 802.11-2012, 8.4.2.61 and MIB defval) */

    scan_params->scan_passive_dwell =

      host_to_le16(20);

    scan_params->scan_active_dwell =

      host_to_le16(10);

    scan_params->scan_passive_total_per_channel =

      host_to_le16(200);

    scan_params->scan_active_total_per_channel =

      host_to_le16(20);

    scan_params->channel_transition_delay_factor =

      host_to_le16(5);

    scan_params->scan_activity_threshold =

      host_to_le16(25);

    pos += sizeof(*scan_params);

  }

  return pos;

}

static void set_ht_param(struct hostapd_data *hapd,

       struct ieee80211_ht_operation *oper)

{

  int secondary_channel = hapd->iconf->secondary_channel;

#ifdef CONFIG_IEEE80211BE

  enum oper_chan_width chwidth = hostapd_get_oper_chwidth(hapd->iconf);

  u16 bw = 0, punct_bitmap = hostapd_get_punct_bitmap(hapd);

  u8 offset, chan_bit_pos;

  switch (chwidth) {

  case CONF_OPER_CHWIDTH_80MHZ:

    bw = 80;

    offset = 6;

    break;

  case CONF_OPER_CHWIDTH_160MHZ:

    bw = 160;

    offset = 14;

    break;

  case CONF_OPER_CHWIDTH_320MHZ:

    bw = 320;

    offset = 30;

    break;

  default:

    goto no_update;

  }

  chan_bit_pos = (hapd->iconf->channel -

      hostapd_get_oper_centr_freq_seg0_idx(hapd->iconf) +

      offset) / 4;

  /* Check if secondary channel is punctured */

  if (bw >= 80 && punct_bitmap && secondary_channel &&

      (punct_bitmap & BIT(chan_bit_pos + secondary_channel)))

    return; /* Do not indicate punctured secondary channel for HT */

no_update:

#endif /* CONFIG_IEEE80211BE */

  if (secondary_channel == 1)

    oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE |

      HT_INFO_HT_PARAM_STA_CHNL_WIDTH;

  if (secondary_channel == -1)

    oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW |

      HT_INFO_HT_PARAM_STA_CHNL_WIDTH;

}

u8 * hostapd_eid_ht_operation(struct hostapd_data *hapd, u8 *eid)

{

  struct ieee80211_ht_operation *oper;

  u8 *pos = eid;

  if (!hapd->iconf->ieee80211n || hapd->conf->disable_11n ||

      is_6ghz_op_class(hapd->iconf->op_class))

    return eid;

  *pos++ = WLAN_EID_HT_OPERATION;

  *pos++ = sizeof(*oper);

  oper = (struct ieee80211_ht_operation *) pos;

  os_memset(oper, 0, sizeof(*oper));

  oper->primary_chan = hapd->iconf->channel;

  oper->operation_mode = host_to_le16(hapd->iface->ht_op_mode);

  set_ht_param(hapd, oper);

  pos += sizeof(*oper);

  return pos;

}

/*

op_mode

Set to 0 (HT pure) under the following conditions

  - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or

  - all STAs in the BSS are 20 MHz HT in 20 MHz BSS

Set to 1 (HT non-member protection) if there may be non-HT STAs

  in both the primary and the secondary channel

Set to 2 if only HT STAs are associated in BSS,

  however and at least one 20 MHz HT STA is associated

Set to 3 (HT mixed mode) when one or more non-HT STAs are associated

*/

int hostapd_ht_operation_update(struct hostapd_iface *iface)

{

  u16 cur_op_mode, new_op_mode;

  int op_mode_changes = 0;

  if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed)

    return 0;

  wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X",

       __func__, iface->ht_op_mode);

  if (!(iface->ht_op_mode & HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT)

      && iface->num_sta_ht_no_gf) {

    iface->ht_op_mode |= HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT;

    op_mode_changes++;

  } else if ((iface->ht_op_mode &

        HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) &&

       iface->num_sta_ht_no_gf == 0) {

    iface->ht_op_mode &= ~HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT;

    op_mode_changes++;

  }

  if (!(iface->ht_op_mode & HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) &&

      (iface->num_sta_no_ht || iface->olbc_ht)) {

    iface->ht_op_mode |= HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT;

    op_mode_changes++;

  } else if ((iface->ht_op_mode &

        HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) &&

       (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) {

    iface->ht_op_mode &= ~HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT;

    op_mode_changes++;

  }

  if (iface->num_sta_no_ht)

    new_op_mode = HT_PROT_NON_HT_MIXED;

  else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz)

    new_op_mode = HT_PROT_20MHZ_PROTECTION;

  else if (iface->olbc_ht)

    new_op_mode = HT_PROT_NONMEMBER_PROTECTION;

  else

    new_op_mode = HT_PROT_NO_PROTECTION;

  cur_op_mode = iface->ht_op_mode & HT_OPER_OP_MODE_HT_PROT_MASK;

  if (cur_op_mode != new_op_mode) {

    iface->ht_op_mode &= ~HT_OPER_OP_MODE_HT_PROT_MASK;

    iface->ht_op_mode |= new_op_mode;

    op_mode_changes++;

  }

  wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d",

       __func__, iface->ht_op_mode, op_mode_changes);

  return op_mode_changes;

}

static int is_40_allowed(struct hostapd_iface *iface, int channel)

{

  int pri_freq, sec_freq;

  int affected_start, affected_end;

  int pri = 2407 + 5 * channel;

  if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)

    return 1;

  pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);

  if (iface->conf->secondary_channel > 0)

    sec_freq = pri_freq + 20;

  else

    sec_freq = pri_freq - 20;

  affected_start = (pri_freq + sec_freq) / 2 - 25;

  affected_end = (pri_freq + sec_freq) / 2 + 25;

  if ((pri < affected_start || pri > affected_end))

    return 1; /* not within affected channel range */

  wpa_printf(MSG_ERROR, "40 MHz affected channel range: [%d,%d] MHz",

       affected_start, affected_end);

  wpa_printf(MSG_ERROR, "Neighboring BSS: freq=%d", pri);

  return 0;

}

void hostapd_2040_coex_action(struct hostapd_data *hapd,

            const struct ieee80211_mgmt *mgmt, size_t len)

{

  struct hostapd_iface *iface = hapd->iface;

  struct ieee80211_2040_bss_coex_ie *bc_ie;

  struct ieee80211_2040_intol_chan_report *ic_report;

  int is_ht40_allowed = 1;

  int i;

  const u8 *start = (const u8 *) mgmt;

  const u8 *data = start + IEEE80211_HDRLEN + 2;

  struct sta_info *sta;

  wpa_printf(MSG_DEBUG,

       "HT: Received 20/40 BSS Coexistence Management frame from "

       MACSTR, MAC2STR(mgmt->sa));

  hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,

           HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",

           mgmt->u.action.u.public_action.action);

  if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {

    wpa_printf(MSG_DEBUG,

         "Ignore 20/40 BSS Coexistence Management frame since 40 MHz capability is not enabled");

    return;

  }

  if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie)) {

    wpa_printf(MSG_DEBUG,

         "Ignore too short 20/40 BSS Coexistence Management frame");

    return;

  }

  /* 20/40 BSS Coexistence element */

  bc_ie = (struct ieee80211_2040_bss_coex_ie *) data;

  if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE ||

      bc_ie->length < 1) {

    wpa_printf(MSG_DEBUG, "Unexpected IE (%u,%u) in coex report",

         bc_ie->element_id, bc_ie->length);

    return;

  }

  if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length) {

    wpa_printf(MSG_DEBUG,

         "Truncated 20/40 BSS Coexistence element");

    return;

  }

  data += 2 + bc_ie->length;

  wpa_printf(MSG_DEBUG,

       "20/40 BSS Coexistence Information field: 0x%x (%s%s%s%s%s%s)",

       bc_ie->coex_param,

       (bc_ie->coex_param & BIT(0)) ? "[InfoReq]" : "",

       (bc_ie->coex_param & BIT(1)) ? "[40MHzIntolerant]" : "",

       (bc_ie->coex_param & BIT(2)) ? "[20MHzBSSWidthReq]" : "",

       (bc_ie->coex_param & BIT(3)) ? "[OBSSScanExemptionReq]" : "",

       (bc_ie->coex_param & BIT(4)) ?

       "[OBSSScanExemptionGrant]" : "",

       (bc_ie->coex_param & (BIT(5) | BIT(6) | BIT(7))) ?

       "[Reserved]" : "");

  if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {

    /* Intra-BSS communication prohibiting 20/40 MHz BSS operation

     */

    sta = ap_get_sta(hapd, mgmt->sa);

    if (!sta || !(sta->flags & WLAN_STA_ASSOC)) {

      wpa_printf(MSG_DEBUG,

           "Ignore intra-BSS 20/40 BSS Coexistence Management frame from not-associated STA");

      return;

    }

    hostapd_logger(hapd, mgmt->sa,

             HOSTAPD_MODULE_IEEE80211,

             HOSTAPD_LEVEL_DEBUG,

             "20 MHz BSS width request bit is set in BSS coexistence information field");

    is_ht40_allowed = 0;

  }

  if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {

    /* Inter-BSS communication prohibiting 20/40 MHz BSS operation

     */

    hostapd_logger(hapd, mgmt->sa,

             HOSTAPD_MODULE_IEEE80211,

             HOSTAPD_LEVEL_DEBUG,

             "40 MHz intolerant bit is set in BSS coexistence information field");

    is_ht40_allowed = 0;

  }

  /* 20/40 BSS Intolerant Channel Report element (zero or more times) */

  while (start + len - data >= 3 &&

         data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) {

    u8 ielen = data[1];

    if (ielen > start + len - data - 2) {

      wpa_printf(MSG_DEBUG,

           "Truncated 20/40 BSS Intolerant Channel Report element");

      return;

    }

    ic_report = (struct ieee80211_2040_intol_chan_report *) data;

    wpa_printf(MSG_DEBUG,

         "20/40 BSS Intolerant Channel Report: Operating Class %u",

         ic_report->op_class);

    /* Go through the channel report to find any BSS there in the

     * affected channel range */

    for (i = 0; i < ielen - 1; i++) {

      u8 chan = ic_report->variable[i];

      if (chan == iface->conf->channel)

        continue; /* matching own primary channel */

      if (is_40_allowed(iface, chan))

        continue; /* not within affected channels */

      hostapd_logger(hapd, mgmt->sa,

               HOSTAPD_MODULE_IEEE80211,

               HOSTAPD_LEVEL_DEBUG,

               "20_40_INTOLERANT channel %d reported",

               chan);

      is_ht40_allowed = 0;

    }

    data += 2 + ielen;

  }

  wpa_printf(MSG_DEBUG, "is_ht40_allowed=%d num_sta_ht40_intolerant=%d",

       is_ht40_allowed, iface->num_sta_ht40_intolerant);

  if (!is_ht40_allowed &&

      (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {

    if (iface->conf->secondary_channel) {

      hostapd_logger(hapd, mgmt->sa,

               HOSTAPD_MODULE_IEEE80211,

               HOSTAPD_LEVEL_INFO,

               "Switching to 20 MHz operation");

      iface->conf->secondary_channel = 0;

      ieee802_11_set_beacons(iface);

    }

    if (!iface->num_sta_ht40_intolerant &&

        iface->conf->obss_interval) {

      unsigned int delay_time;

      delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *

        iface->conf->obss_interval;

      eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface,

               NULL);

      eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,

                 hapd->iface, NULL);

      wpa_printf(MSG_DEBUG,

           "Reschedule HT 20/40 timeout to occur in %u seconds",

           delay_time);

    }

  }

}

u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta,

          const u8 *ht_capab)

{

  /*

   * Disable HT caps for STAs associated to no-HT BSSes, or for stations

   * that did not specify a valid WMM IE in the (Re)Association Request

   * frame.

   */

  if (!ht_capab || !(sta->flags & WLAN_STA_WMM) ||

      !hapd->iconf->ieee80211n || hapd->conf->disable_11n) {

    sta->flags &= ~WLAN_STA_HT;

    os_free(sta->ht_capabilities);

    sta->ht_capabilities = NULL;

    return WLAN_STATUS_SUCCESS;

  }

  if (sta->ht_capabilities == NULL) {

    sta->ht_capabilities =

      os_zalloc(sizeof(struct ieee80211_ht_capabilities));

    if (sta->ht_capabilities == NULL)

      return WLAN_STATUS_UNSPECIFIED_FAILURE;

  }

  sta->flags |= WLAN_STA_HT;

  os_memcpy(sta->ht_capabilities, ht_capab,

      sizeof(struct ieee80211_ht_capabilities));

  return WLAN_STATUS_SUCCESS;

}

void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta)

{

  if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)

    return;

  wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR

       " in Association Request", MAC2STR(sta->addr));

  if (sta->ht40_intolerant_set)

    return;

  sta->ht40_intolerant_set = 1;

  iface->num_sta_ht40_intolerant++;

  eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);

  if (iface->conf->secondary_channel &&

      (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {

    iface->conf->secondary_channel = 0;

    ieee802_11_set_beacons(iface);

  }

}

void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta)

{

  if (!sta->ht40_intolerant_set)

    return;

  sta->ht40_intolerant_set = 0;

  iface->num_sta_ht40_intolerant--;

  if (iface->num_sta_ht40_intolerant == 0 &&

      iface->conf->obss_interval &&

      (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&

      (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {

    unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *

      iface->conf->obss_interval;

    wpa_printf(MSG_DEBUG,

         "HT: Start 20->40 MHz transition timer (%d seconds)",

         delay_time);

    eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);

    eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,

               iface, NULL);

  }

}

static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta)

{

  u16 ht_capab;

  ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info);

  wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: "

       "0x%04x", MAC2STR(sta->addr), ht_capab);

  if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) {

    if (!sta->no_ht_gf_set) {

      sta->no_ht_gf_set = 1;

      hapd->iface->num_sta_ht_no_gf++;

    }

    wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num "

         "of non-gf stations %d",

         __func__, MAC2STR(sta->addr),

         hapd->iface->num_sta_ht_no_gf);

  }

  if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) {

    if (!sta->ht_20mhz_set) {

      sta->ht_20mhz_set = 1;

      hapd->iface->num_sta_ht_20mhz++;

    }

    wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of "

         "20MHz HT STAs %d",

         __func__, MAC2STR(sta->addr),

         hapd->iface->num_sta_ht_20mhz);

  }

  if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT)

    ht40_intolerant_add(hapd->iface, sta);

}

static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta)

{

  if (!sta->no_ht_set) {

    sta->no_ht_set = 1;

    hapd->iface->num_sta_no_ht++;

  }

  if (hapd->iconf->ieee80211n) {

    wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of "

         "non-HT stations %d",

         __func__, MAC2STR(sta->addr),

         hapd->iface->num_sta_no_ht);

  }

}

int update_ht_state(struct hostapd_data *hapd, struct sta_info *sta)

{

  if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities)

    update_sta_ht(hapd, sta);

  else

    update_sta_no_ht(hapd, sta);

  return hostapd_ht_operation_update(hapd->iface);

}

void hostapd_get_ht_capab(struct hostapd_data *hapd,

        struct ieee80211_ht_capabilities *ht_cap,

        struct ieee80211_ht_capabilities *neg_ht_cap)

{

  u16 cap;

  if (ht_cap == NULL)

    return;

  os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap));

  cap = le_to_host16(neg_ht_cap->ht_capabilities_info);

  /*

   * Mask out HT features we don't support, but don't overwrite

   * non-symmetric features like STBC and SMPS. Just because

   * we're not in dynamic SMPS mode the STA might still be.

   */

  cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK |

    HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK);

  /*

   * STBC needs to be handled specially

   * if we don't support RX STBC, mask out TX STBC in the STA's HT caps

   * if we don't support TX STBC, mask out RX STBC in the STA's HT caps

   */

  if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK))

    cap &= ~HT_CAP_INFO_TX_STBC;

  if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC))

    cap &= ~HT_CAP_INFO_RX_STBC_MASK;

  neg_ht_cap->ht_capabilities_info = host_to_le16(cap);

}

void ap_ht2040_timeout(void *eloop_data, void *user_data)

{

  struct hostapd_iface *iface = eloop_data;

  wpa_printf(MSG_INFO, "Switching to 40 MHz operation");

  iface->conf->secondary_channel = iface->secondary_ch;

  ieee802_11_set_beacons(iface);

}