krackattacks/src/ap/neighbor_db.c

/*
 * hostapd / Neighboring APs DB
 * Copyright(c) 2013 - 2016 Intel Mobile Communications GmbH.
 * Copyright(c) 2011 - 2016 Intel Corporation. All rights reserved.
 *
 * 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 "hostapd.h"
#include "neighbor_db.h"


struct hostapd_neighbor_entry *
hostapd_neighbor_get(struct hostapd_data *hapd, const u8 *bssid,
		     const struct wpa_ssid_value *ssid)
{
	struct hostapd_neighbor_entry *nr;

	dl_list_for_each(nr, &hapd->nr_db, struct hostapd_neighbor_entry,
			 list) {
		if (os_memcmp(bssid, nr->bssid, ETH_ALEN) == 0 &&
		    (!ssid ||
		     (ssid->ssid_len == nr->ssid.ssid_len &&
		      os_memcmp(ssid->ssid, nr->ssid.ssid,
				ssid->ssid_len) == 0)))
			return nr;
	}
	return NULL;
}


static void hostapd_neighbor_clear_entry(struct hostapd_neighbor_entry *nr)
{
	wpabuf_free(nr->nr);
	nr->nr = NULL;
	wpabuf_free(nr->lci);
	nr->lci = NULL;
	wpabuf_free(nr->civic);
	nr->civic = NULL;
	os_memset(nr->bssid, 0, sizeof(nr->bssid));
	os_memset(&nr->ssid, 0, sizeof(nr->ssid));
	nr->stationary = 0;
}


static struct hostapd_neighbor_entry *
hostapd_neighbor_add(struct hostapd_data *hapd)
{
	struct hostapd_neighbor_entry *nr;

	nr = os_zalloc(sizeof(struct hostapd_neighbor_entry));
	if (!nr)
		return NULL;

	dl_list_add(&hapd->nr_db, &nr->list);

	return nr;
}


int hostapd_neighbor_set(struct hostapd_data *hapd, const u8 *bssid,
			 const struct wpa_ssid_value *ssid,
			 const struct wpabuf *nr, const struct wpabuf *lci,
			 const struct wpabuf *civic, int stationary)
{
	struct hostapd_neighbor_entry *entry;

	entry = hostapd_neighbor_get(hapd, bssid, ssid);
	if (!entry)
		entry = hostapd_neighbor_add(hapd);
	if (!entry)
		return -1;

	hostapd_neighbor_clear_entry(entry);

	os_memcpy(entry->bssid, bssid, ETH_ALEN);
	os_memcpy(&entry->ssid, ssid, sizeof(entry->ssid));

	entry->nr = wpabuf_dup(nr);
	if (!entry->nr)
		goto fail;

	if (lci && wpabuf_len(lci)) {
		entry->lci = wpabuf_dup(lci);
		if (!entry->lci || os_get_time(&entry->lci_date))
			goto fail;
	}

	if (civic && wpabuf_len(civic)) {
		entry->civic = wpabuf_dup(civic);
		if (!entry->civic)
			goto fail;
	}

	entry->stationary = stationary;

	return 0;

fail:
	hostapd_neighbor_remove(hapd, bssid, ssid);
	return -1;
}


int hostapd_neighbor_remove(struct hostapd_data *hapd, const u8 *bssid,
			    const struct wpa_ssid_value *ssid)
{
	struct hostapd_neighbor_entry *nr;

	nr = hostapd_neighbor_get(hapd, bssid, ssid);
	if (!nr)
		return -1;

	hostapd_neighbor_clear_entry(nr);
	dl_list_del(&nr->list);
	os_free(nr);

	return 0;
}


void hostpad_free_neighbor_db(struct hostapd_data *hapd)
{
	struct hostapd_neighbor_entry *nr, *prev;

	dl_list_for_each_safe(nr, prev, &hapd->nr_db,
			      struct hostapd_neighbor_entry, list) {
		hostapd_neighbor_clear_entry(nr);
		dl_list_del(&nr->list);
		os_free(nr);
	}
}