hostap/wpa_supplicant/ap.c

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/*
* WPA Supplicant - Basic AP mode support routines
* Copyright (c) 2003-2009, Jouni Malinen <j@w1.fi>
* Copyright (c) 2009, Atheros Communications
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "ap/hostapd.h"
#include "ap/ap_config.h"
#ifdef NEED_AP_MLME
#include "ap/ieee802_11.h"
#endif /* NEED_AP_MLME */
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#include "ap/beacon.h"
#include "ap/ieee802_1x.h"
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#include "ap/wps_hostapd.h"
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#include "ap/ctrl_iface_ap.h"
#include "eap_common/eap_defs.h"
#include "eap_server/eap_methods.h"
#include "eap_common/eap_wsc_common.h"
#include "wps/wps.h"
#include "common/ieee802_11_defs.h"
#include "config_ssid.h"
#include "config.h"
#include "wpa_supplicant_i.h"
#include "driver_i.h"
#include "p2p_supplicant.h"
#include "ap.h"
#include "ap/sta_info.h"
static int wpa_supplicant_conf_ap(struct wpa_supplicant *wpa_s,
struct wpa_ssid *ssid,
struct hostapd_config *conf)
{
struct hostapd_bss_config *bss = &conf->bss[0];
int pairwise;
conf->driver = wpa_s->driver;
os_strlcpy(bss->iface, wpa_s->ifname, sizeof(bss->iface));
if (ssid->frequency == 0) {
/* default channel 11 */
conf->hw_mode = HOSTAPD_MODE_IEEE80211G;
conf->channel = 11;
} else if (ssid->frequency >= 2412 && ssid->frequency <= 2472) {
conf->hw_mode = HOSTAPD_MODE_IEEE80211G;
conf->channel = (ssid->frequency - 2407) / 5;
} else if ((ssid->frequency >= 5180 && ssid->frequency <= 5240) ||
(ssid->frequency >= 5745 && ssid->frequency <= 5825)) {
conf->hw_mode = HOSTAPD_MODE_IEEE80211A;
conf->channel = (ssid->frequency - 5000) / 5;
} else {
wpa_printf(MSG_ERROR, "Unsupported AP mode frequency: %d MHz",
ssid->frequency);
return -1;
}
/* TODO: enable HT if driver supports it;
* drop to 11b if driver does not support 11g */
#ifdef CONFIG_P2P
if (conf->hw_mode == HOSTAPD_MODE_IEEE80211G) {
/* Remove 802.11b rates from supported and basic rate sets */
int *list = os_malloc(4 * sizeof(int));
if (list) {
list[0] = 60;
list[1] = 120;
list[2] = 240;
list[3] = -1;
}
conf->basic_rates = list;
list = os_malloc(9 * sizeof(int));
if (list) {
list[0] = 60;
list[1] = 90;
list[2] = 120;
list[3] = 180;
list[4] = 240;
list[5] = 360;
list[6] = 480;
list[7] = 540;
list[8] = -1;
}
conf->supported_rates = list;
}
#endif /* CONFIG_P2P */
if (ssid->ssid_len == 0) {
wpa_printf(MSG_ERROR, "No SSID configured for AP mode");
return -1;
}
os_memcpy(bss->ssid.ssid, ssid->ssid, ssid->ssid_len);
bss->ssid.ssid[ssid->ssid_len] = '\0';
bss->ssid.ssid_len = ssid->ssid_len;
bss->ssid.ssid_set = 1;
if (wpa_key_mgmt_wpa_psk(ssid->key_mgmt))
bss->wpa = ssid->proto;
bss->wpa_key_mgmt = ssid->key_mgmt;
bss->wpa_pairwise = ssid->pairwise_cipher;
if (ssid->passphrase) {
bss->ssid.wpa_passphrase = os_strdup(ssid->passphrase);
} else if (ssid->psk_set) {
os_free(bss->ssid.wpa_psk);
bss->ssid.wpa_psk = os_zalloc(sizeof(struct hostapd_wpa_psk));
if (bss->ssid.wpa_psk == NULL)
return -1;
os_memcpy(bss->ssid.wpa_psk->psk, ssid->psk, PMK_LEN);
bss->ssid.wpa_psk->group = 1;
}
/* Select group cipher based on the enabled pairwise cipher suites */
pairwise = 0;
if (bss->wpa & 1)
pairwise |= bss->wpa_pairwise;
if (bss->wpa & 2) {
if (bss->rsn_pairwise == 0)
bss->rsn_pairwise = bss->wpa_pairwise;
pairwise |= bss->rsn_pairwise;
}
if (pairwise & WPA_CIPHER_TKIP)
bss->wpa_group = WPA_CIPHER_TKIP;
else
bss->wpa_group = WPA_CIPHER_CCMP;
if (bss->wpa && bss->ieee802_1x)
bss->ssid.security_policy = SECURITY_WPA;
else if (bss->wpa)
bss->ssid.security_policy = SECURITY_WPA_PSK;
else if (bss->ieee802_1x) {
bss->ssid.security_policy = SECURITY_IEEE_802_1X;
bss->ssid.wep.default_len = bss->default_wep_key_len;
} else if (bss->ssid.wep.keys_set)
bss->ssid.security_policy = SECURITY_STATIC_WEP;
else
bss->ssid.security_policy = SECURITY_PLAINTEXT;
#ifdef CONFIG_WPS
/*
* Enable WPS by default, but require user interaction to actually use
* it. Only the internal Registrar is supported.
*/
bss->eap_server = 1;
bss->wps_state = 2;
bss->ap_setup_locked = 1;
if (wpa_s->conf->config_methods)
bss->config_methods = os_strdup(wpa_s->conf->config_methods);
if (wpa_s->conf->device_type)
bss->device_type = os_strdup(wpa_s->conf->device_type);
if (wpa_s->conf->device_name) {
bss->device_name = os_strdup(wpa_s->conf->device_name);
bss->friendly_name = os_strdup(wpa_s->conf->device_name);
}
if (wpa_s->conf->manufacturer)
bss->manufacturer = os_strdup(wpa_s->conf->manufacturer);
if (wpa_s->conf->model_name)
bss->model_name = os_strdup(wpa_s->conf->model_name);
if (wpa_s->conf->model_number)
bss->model_number = os_strdup(wpa_s->conf->model_number);
if (wpa_s->conf->serial_number)
bss->serial_number = os_strdup(wpa_s->conf->serial_number);
os_memcpy(bss->uuid, wpa_s->conf->uuid, WPS_UUID_LEN);
os_memcpy(bss->os_version, wpa_s->conf->os_version, 4);
#endif /* CONFIG_WPS */
return 0;
}
static void ap_public_action_rx(void *ctx, const u8 *buf, size_t len, int freq)
{
#ifdef CONFIG_P2P
struct wpa_supplicant *wpa_s = ctx;
const struct ieee80211_mgmt *mgmt;
size_t hdr_len;
mgmt = (const struct ieee80211_mgmt *) buf;
hdr_len = (const u8 *) &mgmt->u.action.u.vs_public_action.action - buf;
if (hdr_len > len)
return;
wpas_p2p_rx_action(wpa_s, mgmt->da, mgmt->sa, mgmt->bssid,
mgmt->u.action.category,
&mgmt->u.action.u.vs_public_action.action,
len - hdr_len, freq);
#endif /* CONFIG_P2P */
}
static int ap_vendor_action_rx(void *ctx, const u8 *buf, size_t len, int freq)
{
#ifdef CONFIG_P2P
struct wpa_supplicant *wpa_s = ctx;
const struct ieee80211_mgmt *mgmt;
size_t hdr_len;
mgmt = (const struct ieee80211_mgmt *) buf;
hdr_len = (const u8 *) &mgmt->u.action.u.vs_public_action.action - buf;
if (hdr_len > len)
return -1;
wpas_p2p_rx_action(wpa_s, mgmt->da, mgmt->sa, mgmt->bssid,
mgmt->u.action.category,
&mgmt->u.action.u.vs_public_action.action,
len - hdr_len, freq);
#endif /* CONFIG_P2P */
return 0;
}
static int ap_probe_req_rx(void *ctx, const u8 *addr, const u8 *ie,
size_t ie_len)
{
#ifdef CONFIG_P2P
struct wpa_supplicant *wpa_s = ctx;
return wpas_p2p_probe_req_rx(wpa_s, addr, ie, ie_len);
#else /* CONFIG_P2P */
return 0;
#endif /* CONFIG_P2P */
}
static void ap_wps_reg_success_cb(void *ctx, const u8 *mac_addr,
const u8 *uuid_e)
{
#ifdef CONFIG_P2P
struct wpa_supplicant *wpa_s = ctx;
wpas_p2p_wps_success(wpa_s, mac_addr, 1);
#endif /* CONFIG_P2P */
}
int wpa_supplicant_create_ap(struct wpa_supplicant *wpa_s,
struct wpa_ssid *ssid)
{
struct wpa_driver_associate_params params;
struct hostapd_iface *hapd_iface;
struct hostapd_config *conf;
size_t i;
if (ssid->ssid == NULL || ssid->ssid_len == 0) {
wpa_printf(MSG_ERROR, "No SSID configured for AP mode");
return -1;
}
wpa_supplicant_ap_deinit(wpa_s);
wpa_printf(MSG_DEBUG, "Setting up AP (SSID='%s')",
wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
os_memset(&params, 0, sizeof(params));
params.ssid = ssid->ssid;
params.ssid_len = ssid->ssid_len;
switch (ssid->mode) {
case WPAS_MODE_INFRA:
params.mode = IEEE80211_MODE_INFRA;
break;
case WPAS_MODE_IBSS:
params.mode = IEEE80211_MODE_IBSS;
break;
case WPAS_MODE_AP:
case WPAS_MODE_P2P_GO:
case WPAS_MODE_P2P_GROUP_FORMATION:
params.mode = IEEE80211_MODE_AP;
break;
}
params.freq = ssid->frequency;
if (ssid->key_mgmt & WPA_KEY_MGMT_PSK)
wpa_s->key_mgmt = WPA_KEY_MGMT_PSK;
else
wpa_s->key_mgmt = WPA_KEY_MGMT_NONE;
params.key_mgmt_suite = key_mgmt2driver(wpa_s->key_mgmt);
if (ssid->pairwise_cipher & WPA_CIPHER_CCMP)
wpa_s->pairwise_cipher = WPA_CIPHER_CCMP;
else if (ssid->pairwise_cipher & WPA_CIPHER_TKIP)
wpa_s->pairwise_cipher = WPA_CIPHER_TKIP;
else if (ssid->pairwise_cipher & WPA_CIPHER_NONE)
wpa_s->pairwise_cipher = WPA_CIPHER_NONE;
else {
wpa_printf(MSG_WARNING, "WPA: Failed to select pairwise "
"cipher.");
return -1;
}
params.pairwise_suite = cipher_suite2driver(wpa_s->pairwise_cipher);
params.group_suite = params.pairwise_suite;
#ifdef CONFIG_P2P
if (ssid->mode == WPAS_MODE_P2P_GO ||
ssid->mode == WPAS_MODE_P2P_GROUP_FORMATION)
params.p2p = 1;
#endif /* CONFIG_P2P */
if (wpa_s->parent->set_ap_uapsd)
params.uapsd = wpa_s->parent->ap_uapsd;
else
params.uapsd = -1;
if (wpa_drv_associate(wpa_s, &params) < 0) {
wpa_msg(wpa_s, MSG_INFO, "Failed to start AP functionality");
return -1;
}
wpa_s->ap_iface = hapd_iface = os_zalloc(sizeof(*wpa_s->ap_iface));
if (hapd_iface == NULL)
return -1;
hapd_iface->owner = wpa_s;
wpa_s->ap_iface->conf = conf = hostapd_config_defaults();
if (conf == NULL) {
wpa_supplicant_ap_deinit(wpa_s);
return -1;
}
if (wpa_supplicant_conf_ap(wpa_s, ssid, conf)) {
wpa_printf(MSG_ERROR, "Failed to create AP configuration");
wpa_supplicant_ap_deinit(wpa_s);
return -1;
}
#ifdef CONFIG_P2P
if (ssid->mode == WPAS_MODE_P2P_GO)
conf->bss[0].p2p = P2P_ENABLED | P2P_GROUP_OWNER;
else if (ssid->mode == WPAS_MODE_P2P_GROUP_FORMATION)
conf->bss[0].p2p = P2P_ENABLED | P2P_GROUP_OWNER |
P2P_GROUP_FORMATION;
#endif /* CONFIG_P2P */
hapd_iface->num_bss = conf->num_bss;
hapd_iface->bss = os_zalloc(conf->num_bss *
sizeof(struct hostapd_data *));
if (hapd_iface->bss == NULL) {
wpa_supplicant_ap_deinit(wpa_s);
return -1;
}
for (i = 0; i < conf->num_bss; i++) {
hapd_iface->bss[i] =
hostapd_alloc_bss_data(hapd_iface, conf,
&conf->bss[i]);
if (hapd_iface->bss[i] == NULL) {
wpa_supplicant_ap_deinit(wpa_s);
return -1;
}
hapd_iface->bss[i]->msg_ctx = wpa_s;
hapd_iface->bss[i]->public_action_cb = ap_public_action_rx;
hapd_iface->bss[i]->public_action_cb_ctx = wpa_s;
hapd_iface->bss[i]->vendor_action_cb = ap_vendor_action_rx;
hapd_iface->bss[i]->vendor_action_cb_ctx = wpa_s;
hostapd_register_probereq_cb(hapd_iface->bss[i],
ap_probe_req_rx, wpa_s);
hapd_iface->bss[i]->wps_reg_success_cb = ap_wps_reg_success_cb;
hapd_iface->bss[i]->wps_reg_success_cb_ctx = wpa_s;
#ifdef CONFIG_P2P
hapd_iface->bss[i]->p2p = wpa_s->global->p2p;
hapd_iface->bss[i]->p2p_group = wpas_p2p_group_init(
wpa_s, ssid->p2p_persistent_group,
ssid->mode == WPAS_MODE_P2P_GROUP_FORMATION);
#endif /* CONFIG_P2P */
}
os_memcpy(hapd_iface->bss[0]->own_addr, wpa_s->own_addr, ETH_ALEN);
hapd_iface->bss[0]->driver = wpa_s->driver;
hapd_iface->bss[0]->drv_priv = wpa_s->drv_priv;
if (hostapd_setup_interface(wpa_s->ap_iface)) {
wpa_printf(MSG_ERROR, "Failed to initialize AP interface");
wpa_supplicant_ap_deinit(wpa_s);
return -1;
}
wpa_s->current_ssid = ssid;
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os_memcpy(wpa_s->bssid, wpa_s->own_addr, ETH_ALEN);
wpa_s->assoc_freq = ssid->frequency;
wpa_supplicant_set_state(wpa_s, WPA_COMPLETED);
if (wpa_s->ap_configured_cb)
wpa_s->ap_configured_cb(wpa_s->ap_configured_cb_ctx,
wpa_s->ap_configured_cb_data);
return 0;
}
void wpa_supplicant_ap_deinit(struct wpa_supplicant *wpa_s)
{
if (wpa_s->ap_iface == NULL)
return;
wpa_s->current_ssid = NULL;
#ifdef CONFIG_P2P
if (wpa_s->ap_iface->bss)
wpa_s->ap_iface->bss[0]->p2p_group = NULL;
wpas_p2p_group_deinit(wpa_s);
#endif /* CONFIG_P2P */
hostapd_interface_deinit(wpa_s->ap_iface);
hostapd_interface_free(wpa_s->ap_iface);
wpa_s->ap_iface = NULL;
wpa_drv_deinit_ap(wpa_s);
}
void ap_tx_status(void *ctx, const u8 *addr,
const u8 *buf, size_t len, int ack)
{
#ifdef NEED_AP_MLME
struct wpa_supplicant *wpa_s = ctx;
hostapd_tx_status(wpa_s->ap_iface->bss[0], addr, buf, len, ack);
#endif /* NEED_AP_MLME */
}
void ap_rx_from_unknown_sta(void *ctx, const u8 *frame, size_t len)
{
#ifdef NEED_AP_MLME
struct wpa_supplicant *wpa_s = ctx;
const struct ieee80211_hdr *hdr =
(const struct ieee80211_hdr *) frame;
u16 fc = le_to_host16(hdr->frame_control);
ieee802_11_rx_from_unknown(wpa_s->ap_iface->bss[0], hdr->addr2,
(fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) ==
(WLAN_FC_TODS | WLAN_FC_FROMDS));
#endif /* NEED_AP_MLME */
}
void ap_mgmt_rx(void *ctx, struct rx_mgmt *rx_mgmt)
{
#ifdef NEED_AP_MLME
struct wpa_supplicant *wpa_s = ctx;
struct hostapd_frame_info fi;
os_memset(&fi, 0, sizeof(fi));
fi.datarate = rx_mgmt->datarate;
fi.ssi_signal = rx_mgmt->ssi_signal;
ieee802_11_mgmt(wpa_s->ap_iface->bss[0], rx_mgmt->frame,
rx_mgmt->frame_len, &fi);
#endif /* NEED_AP_MLME */
}
void ap_mgmt_tx_cb(void *ctx, const u8 *buf, size_t len, u16 stype, int ok)
{
#ifdef NEED_AP_MLME
struct wpa_supplicant *wpa_s = ctx;
ieee802_11_mgmt_cb(wpa_s->ap_iface->bss[0], buf, len, stype, ok);
#endif /* NEED_AP_MLME */
}
void wpa_supplicant_ap_rx_eapol(struct wpa_supplicant *wpa_s,
const u8 *src_addr, const u8 *buf, size_t len)
{
ieee802_1x_receive(wpa_s->ap_iface->bss[0], src_addr, buf, len);
}
#ifdef CONFIG_WPS
int wpa_supplicant_ap_wps_pbc(struct wpa_supplicant *wpa_s, const u8 *bssid)
{
if (!wpa_s->ap_iface)
return -1;
return hostapd_wps_button_pushed(wpa_s->ap_iface->bss[0]);
}
static int wpa_supplicant_ap_wps_sta_cancel(struct hostapd_data *hapd,
struct sta_info *sta, void *ctx)
{
if (sta && (sta->flags & WLAN_STA_WPS)) {
ap_sta_deauthenticate(hapd, sta,
WLAN_REASON_PREV_AUTH_NOT_VALID);
wpa_printf(MSG_DEBUG, "WPS: %s: Deauth sta=" MACSTR,
__func__, MAC2STR(sta->addr));
return 1;
}
return 0;
}
int wpa_supplicant_ap_wps_cancel(struct wpa_supplicant *wpa_s)
{
struct wps_registrar *reg;
int reg_sel = 0, wps_sta = 0;
if (!wpa_s->ap_iface || !wpa_s->ap_iface->bss[0]->wps)
return -1;
reg = wpa_s->ap_iface->bss[0]->wps->registrar;
reg_sel = wps_registrar_wps_cancel(reg);
wps_sta = ap_for_each_sta(wpa_s->ap_iface->bss[0],
wpa_supplicant_ap_wps_sta_cancel, NULL);
if (!reg_sel && !wps_sta) {
wpa_printf(MSG_DEBUG, "No WPS operation in progress at this "
"time");
return -1;
}
/*
* There are 2 cases to return wps cancel as success:
* 1. When wps cancel was initiated but no connection has been
* established with client yet.
* 2. Client is in the middle of exchanging WPS messages.
*/
return 0;
}
int wpa_supplicant_ap_wps_pin(struct wpa_supplicant *wpa_s, const u8 *bssid,
const char *pin, char *buf, size_t buflen)
{
int ret, ret_len = 0;
if (!wpa_s->ap_iface)
return -1;
if (pin == NULL) {
unsigned int rpin = wps_generate_pin();
ret_len = os_snprintf(buf, buflen, "%d", rpin);
pin = buf;
} else
ret_len = os_snprintf(buf, buflen, "%s", pin);
ret = hostapd_wps_add_pin(wpa_s->ap_iface->bss[0], bssid, "any", pin,
0);
if (ret)
return -1;
return ret_len;
}
#endif /* CONFIG_WPS */
#ifdef CONFIG_CTRL_IFACE
int ap_ctrl_iface_sta_first(struct wpa_supplicant *wpa_s,
char *buf, size_t buflen)
{
if (wpa_s->ap_iface == NULL)
return -1;
return hostapd_ctrl_iface_sta_first(wpa_s->ap_iface->bss[0],
buf, buflen);
}
int ap_ctrl_iface_sta(struct wpa_supplicant *wpa_s, const char *txtaddr,
char *buf, size_t buflen)
{
if (wpa_s->ap_iface == NULL)
return -1;
return hostapd_ctrl_iface_sta(wpa_s->ap_iface->bss[0], txtaddr,
buf, buflen);
}
int ap_ctrl_iface_sta_next(struct wpa_supplicant *wpa_s, const char *txtaddr,
char *buf, size_t buflen)
{
if (wpa_s->ap_iface == NULL)
return -1;
return hostapd_ctrl_iface_sta_next(wpa_s->ap_iface->bss[0], txtaddr,
buf, buflen);
}
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int ap_ctrl_iface_wpa_get_status(struct wpa_supplicant *wpa_s, char *buf,
size_t buflen, int verbose)
{
char *pos = buf, *end = buf + buflen;
int ret;
struct hostapd_bss_config *conf;
if (wpa_s->ap_iface == NULL)
return -1;
conf = wpa_s->ap_iface->bss[0]->conf;
if (conf->wpa == 0)
return 0;
ret = os_snprintf(pos, end - pos,
"pairwise_cipher=%s\n"
"group_cipher=%s\n"
"key_mgmt=%s\n",
wpa_cipher_txt(conf->rsn_pairwise),
wpa_cipher_txt(conf->wpa_group),
wpa_key_mgmt_txt(conf->wpa_key_mgmt,
conf->wpa));
if (ret < 0 || ret >= end - pos)
return pos - buf;
pos += ret;
return pos - buf;
}
#endif /* CONFIG_CTRL_IFACE */
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int wpa_supplicant_ap_update_beacon(struct wpa_supplicant *wpa_s)
{
struct hostapd_iface *iface = wpa_s->ap_iface;
struct wpa_ssid *ssid = wpa_s->current_ssid;
struct hostapd_data *hapd;
if (ssid == NULL || wpa_s->ap_iface == NULL)
return -1;
#ifdef CONFIG_P2P
if (ssid->mode == WPAS_MODE_P2P_GO)
iface->conf->bss[0].p2p = P2P_ENABLED | P2P_GROUP_OWNER;
else if (ssid->mode == WPAS_MODE_P2P_GROUP_FORMATION)
iface->conf->bss[0].p2p = P2P_ENABLED | P2P_GROUP_OWNER |
P2P_GROUP_FORMATION;
#endif /* CONFIG_P2P */
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ieee802_11_set_beacons(iface);
hapd = iface->bss[0];
hapd->drv.set_ap_wps_ie(hapd);
return 0;
}
int wpa_supplicant_ap_mac_addr_filter(struct wpa_supplicant *wpa_s,
const u8 *addr)
{
struct hostapd_data *hapd;
struct hostapd_bss_config *conf;
if (!wpa_s->ap_iface)
return -1;
if (addr)
wpa_printf(MSG_DEBUG, "AP: Set MAC address filter: " MACSTR,
MAC2STR(addr));
else
wpa_printf(MSG_DEBUG, "AP: Clear MAC address filter");
hapd = wpa_s->ap_iface->bss[0];
conf = hapd->conf;
os_free(conf->accept_mac);
conf->accept_mac = NULL;
conf->num_accept_mac = 0;
os_free(conf->deny_mac);
conf->deny_mac = NULL;
conf->num_deny_mac = 0;
if (addr == NULL) {
conf->macaddr_acl = ACCEPT_UNLESS_DENIED;
return 0;
}
conf->macaddr_acl = DENY_UNLESS_ACCEPTED;
conf->accept_mac = os_zalloc(sizeof(struct mac_acl_entry));
if (conf->accept_mac == NULL)
return -1;
os_memcpy(conf->accept_mac[0].addr, addr, ETH_ALEN);
conf->num_accept_mac = 1;
return 0;
}