iwd/src/wiphy.c

/*
 *
 *  Wireless daemon for Linux
 *
 *  Copyright (C) 2013-2014  Intel Corporation. All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <sys/socket.h>
#include <linux/if.h>
#include <linux/if_packet.h>
#include <linux/if_ether.h>
#include <time.h>

#include <ell/ell.h>

#include "linux/nl80211.h"
#include "src/iwd.h"
#include "src/ie.h"
#include "src/wiphy.h"
#include "src/dbus.h"
#include "src/scan.h"
#include "src/util.h"
#include "src/common.h"
#include "src/eapol.h"
#include "src/agent.h"
#include "src/crypto.h"
#include "src/netdev.h"
#include "src/mpdu.h"
#include "src/storage.h"
#include "src/network.h"
#include "src/device.h"

static struct l_genl_family *nl80211 = NULL;

struct wiphy {
	uint32_t id;
	char name[20];
	uint32_t feature_flags;
	bool support_scheduled_scan:1;
	bool support_rekey_offload:1;
	uint16_t pairwise_ciphers;
	struct scan_freq_set *supported_freqs;
};

struct autoconnect_entry {
	uint16_t rank;
	struct network *network;
	struct scan_bss *bss;
};

static struct l_queue *wiphy_list = NULL;
static struct l_queue *device_list;

static bool new_scan_results(uint32_t wiphy_id, uint32_t ifindex,
				struct l_queue *bss_list, void *userdata);

static bool eapol_read(struct l_io *io, void *user_data)
{
	struct device *device = user_data;
	struct netdev *netdev = device->netdev;
	int fd = l_io_get_fd(io);
	struct sockaddr_ll sll;
	socklen_t sll_len;
	ssize_t bytes;
	uint8_t frame[2304]; /* IEEE Std 802.11 ch. 8.2.3 */

	memset(&sll, 0, sizeof(sll));
	sll_len = sizeof(sll);

	bytes = recvfrom(fd, frame, sizeof(frame), 0,
				(struct sockaddr *) &sll, &sll_len);
	if (bytes <= 0) {
		l_error("EAPoL read socket: %s", strerror(errno));
		return false;
	}

	__eapol_rx_packet(netdev_get_ifindex(netdev),
				netdev_get_address(netdev),
				sll.sll_addr, frame, bytes);

	return true;
}

static const char *iwd_network_get_path(struct device *device,
					const uint8_t *ssid, size_t ssid_len,
					enum security security)
{
	static char path[256];
	unsigned int pos, i;

	pos = snprintf(path, sizeof(path), "%s/", device_get_path(device));

	for (i = 0; i < ssid_len && pos < sizeof(path); i++)
		pos += snprintf(path + pos, sizeof(path) - pos, "%02x",
								ssid[i]);

	snprintf(path + pos, sizeof(path) - pos, "_%s",
				security_to_str(security));

	return path;
}

static const char *device_state_to_string(enum device_state state)
{
	switch (state) {
	case DEVICE_STATE_DISCONNECTED:
		return "disconnected";
	case DEVICE_STATE_AUTOCONNECT:
		return "autoconnect";
	case DEVICE_STATE_CONNECTING:
		return "connecting";
	case DEVICE_STATE_CONNECTED:
		return "connected";
	case DEVICE_STATE_DISCONNECTING:
		return "disconnecting";
	}

	return "invalid";
}

void device_enter_state(struct device *device, enum device_state state)
{
	l_debug("Old State: %s, new state: %s",
			device_state_to_string(device->state),
			device_state_to_string(state));

	switch (state) {
	case DEVICE_STATE_AUTOCONNECT:
		scan_periodic_start(device->index, new_scan_results, device);
		break;
	case DEVICE_STATE_DISCONNECTED:
		scan_periodic_stop(device->index);
		break;
	case DEVICE_STATE_CONNECTED:
		scan_periodic_stop(device->index);
		break;
	case DEVICE_STATE_CONNECTING:
		break;
	case DEVICE_STATE_DISCONNECTING:
		break;
	}

	device->state = state;
}

enum ie_rsn_cipher_suite wiphy_select_cipher(struct wiphy *wiphy, uint16_t mask)
{
	mask &= wiphy->pairwise_ciphers;

	/* CCMP is our first choice, TKIP second */
	if (mask & IE_RSN_CIPHER_SUITE_CCMP)
		return IE_RSN_CIPHER_SUITE_CCMP;

	if (mask & IE_RSN_CIPHER_SUITE_TKIP)
		return IE_RSN_CIPHER_SUITE_TKIP;

	return 0;
}

static void bss_free(void *data)
{
	struct scan_bss *bss = data;
	const char *addr;

	addr = util_address_to_string(bss->addr);

	l_debug("Freeing BSS %s", addr);

	scan_bss_free(bss);
}

static void network_free(void *data)
{
	struct network *network = data;

	network_remove(network, -ESHUTDOWN);
}

void __iwd_device_foreach(iwd_device_foreach_func func, void *user_data)
{
	const struct l_queue_entry *device_entry;

	for (device_entry = l_queue_get_entries(device_list); device_entry;
					device_entry = device_entry->next) {
		struct device *device = device_entry->data;

		func(device, user_data);
	}
}

static void device_scan_triggered(int err, void *user_data)
{
	struct device *device = user_data;
	struct l_dbus_message *reply;

	l_debug("device_scan_triggered: %i", err);

	if (err < 0) {
		dbus_pending_reply(&device->scan_pending,
				dbus_error_failed(device->scan_pending));
		return;
	}

	l_debug("Scan triggered for %s", netdev_get_name(device->netdev));

	reply = l_dbus_message_new_method_return(device->scan_pending);
	l_dbus_message_set_arguments(reply, "");
	dbus_pending_reply(&device->scan_pending, reply);
}

static struct l_dbus_message *device_scan(struct l_dbus *dbus,
						struct l_dbus_message *message,
						void *user_data)
{
	struct device *device = user_data;

	l_debug("Scan called from DBus");

	if (device->scan_pending)
		return dbus_error_busy(message);

	device->scan_pending = l_dbus_message_ref(message);

	if (!scan_passive(device->index, device_scan_triggered,
				new_scan_results, device, NULL))
		return dbus_error_failed(message);

	return NULL;
}

static void device_disconnect_cb(struct l_genl_msg *msg, void *user_data)
{
	struct device *device = user_data;
	struct l_dbus_message *reply;

	if (l_genl_msg_get_error(msg) < 0) {
		dbus_pending_reply(&device->disconnect_pending,
				dbus_error_failed(device->disconnect_pending));
		return;
	}

	device_disassociated(device);

	reply = l_dbus_message_new_method_return(device->disconnect_pending);
	l_dbus_message_set_arguments(reply, "");
	dbus_pending_reply(&device->disconnect_pending, reply);
}

static struct l_dbus_message *device_disconnect(struct l_dbus *dbus,
						struct l_dbus_message *message,
						void *user_data)
{
	struct device *device = user_data;
	struct l_genl_msg *msg;
	uint16_t reason_code = MPDU_REASON_CODE_DEAUTH_LEAVING;
	enum security security;

	l_debug("");

	if (device->state == DEVICE_STATE_CONNECTING ||
			device->state == DEVICE_STATE_DISCONNECTING)
		return dbus_error_busy(message);

	if (!device->connected_bss)
		return dbus_error_not_connected(message);

	security = network_get_security(device->connected_network);
	if (security == SECURITY_PSK || security == SECURITY_8021X)
		eapol_cancel(device->index);

	msg = l_genl_msg_new_sized(NL80211_CMD_DEAUTHENTICATE, 512);
	msg_append_attr(msg, NL80211_ATTR_IFINDEX, 4, &device->index);
	msg_append_attr(msg, NL80211_ATTR_REASON_CODE, 2, &reason_code);
	msg_append_attr(msg, NL80211_ATTR_MAC, ETH_ALEN,
						device->connected_bss->addr);
	l_genl_family_send(nl80211, msg, device_disconnect_cb, device, NULL);

	device_enter_state(device, DEVICE_STATE_DISCONNECTING);

	device->disconnect_pending = l_dbus_message_ref(message);

	return NULL;
}

static struct l_dbus_message *device_get_networks(struct l_dbus *dbus,
						struct l_dbus_message *message,
						void *user_data)
{
	struct device *device = user_data;
	struct l_dbus_message *reply;
	struct l_dbus_message_builder *builder;
	const struct l_queue_entry *entry;

	reply = l_dbus_message_new_method_return(message);
	builder = l_dbus_message_builder_new(reply);

	l_dbus_message_builder_enter_array(builder, "(osns)");

	for (entry = l_queue_get_entries(device->networks_sorted); entry;
				entry = entry->next) {
		const struct network *network = entry->data;
		enum security security = network_get_security(network);
		int32_t signal_strength = network_get_signal_strength(network);

		l_dbus_message_builder_enter_struct(builder, "osns");
		l_dbus_message_builder_append_basic(builder, 'o',
						network_get_path(network));
		l_dbus_message_builder_append_basic(builder, 's',
						network_get_ssid(network));
		l_dbus_message_builder_append_basic(builder, 'n',
							&signal_strength);
		l_dbus_message_builder_append_basic(builder, 's',
						security_to_str(security));
		l_dbus_message_builder_leave_struct(builder);
	}

	l_dbus_message_builder_leave_array(builder);

	l_dbus_message_builder_finalize(builder);
	l_dbus_message_builder_destroy(builder);

	return reply;
}

static bool device_property_get_name(struct l_dbus *dbus,
					struct l_dbus_message *message,
					struct l_dbus_message_builder *builder,
					void *user_data)
{
	struct device *device = user_data;

	l_dbus_message_builder_append_basic(builder, 's',
					netdev_get_name(device->netdev));
	return true;
}

static bool device_property_get_address(struct l_dbus *dbus,
					struct l_dbus_message *message,
					struct l_dbus_message_builder *builder,
					void *user_data)
{
	struct device *device = user_data;
	const char *str;

	str = util_address_to_string(netdev_get_address(device->netdev));
	l_dbus_message_builder_append_basic(builder, 's', str);

	return true;
}

static bool device_property_get_connected_network(struct l_dbus *dbus,
					struct l_dbus_message *message,
					struct l_dbus_message_builder *builder,
					void *user_data)
{
	struct device *device = user_data;
	if (!device->connected_network)
		return false;

	l_dbus_message_builder_append_basic(builder, 'o',
				network_get_path(device->connected_network));

	return true;
}

static void setup_device_interface(struct l_dbus_interface *interface)
{
	l_dbus_interface_method(interface, "Scan", 0,
				device_scan, "", "");
	l_dbus_interface_method(interface, "Disconnect", 0,
				device_disconnect, "", "");
	l_dbus_interface_method(interface, "GetOrderedNetworks", 0,
				device_get_networks, "a(osns)", "",
				"networks");

	l_dbus_interface_property(interface, "Name", 0, "s",
					device_property_get_name, NULL);
	l_dbus_interface_property(interface, "Address", 0, "s",
					device_property_get_address, NULL);
	l_dbus_interface_property(interface, "ConnectedNetwork", 0, "o",
					device_property_get_connected_network,
					NULL);
}

static bool bss_match(const void *a, const void *b)
{
	const struct scan_bss *bss_a = a;
	const struct scan_bss *bss_b = b;

	return !memcmp(bss_a->addr, bss_b->addr, sizeof(bss_a->addr));
}

static void device_autoconnect_next(struct device *device)
{
	struct autoconnect_entry *entry;
	int r;

	while ((entry = l_queue_pop_head(device->autoconnect_list))) {
		l_debug("Considering autoconnecting to BSS '%s' with SSID: %s,"
			" freq: %u, rank: %u, strength: %i",
			util_address_to_string(entry->bss->addr),
			network_get_ssid(entry->network),
			entry->bss->frequency, entry->rank,
			entry->bss->signal_strength);

		/* TODO: Blacklist the network from auto-connect */
		r = network_autoconnect(entry->network, entry->bss);
		l_free(entry);

		if (!r)
			return;
	}
}

static void wiphy_free(void *data)
{
	struct wiphy *wiphy = data;

	l_debug("Freeing wiphy %s", wiphy->name);

	scan_freq_set_free(wiphy->supported_freqs);
	l_free(wiphy);
}

static bool wiphy_match(const void *a, const void *b)
{
	const struct wiphy *wiphy = a;
	uint32_t id = L_PTR_TO_UINT(b);

	return (wiphy->id == id);
}

static bool process_network(const void *key, void *data, void *user_data)
{
	struct network *network = data;
	struct device *device = user_data;

	if (!network_bss_list_isempty(network)) {
		/* Build the network list ordered by rank */
		network_rank_update(network);

		l_queue_insert(device->networks_sorted, network,
				network_rank_compare, NULL);

		return false;
	}

	/* Drop networks that have no more BSSs in range */
	l_debug("No remaining BSSs for SSID: %s -- Removing network",
			network_get_ssid(network));
	network_remove(network, -ERANGE);

	return true;
}

static int autoconnect_rank_compare(const void *a, const void *b, void *user)
{
	const struct autoconnect_entry *new_ae = a;
	const struct autoconnect_entry *ae = b;

	return ae->rank - new_ae->rank;
}

static void process_bss(struct device *device, struct scan_bss *bss,
			struct timespec *timestamp)
{
	struct network *network;
	enum security security;
	const char *path;
	double rankmod;
	struct autoconnect_entry *entry;

	l_debug("Found BSS '%s' with SSID: %s, freq: %u, rank: %u, "
			"strength: %i",
			util_address_to_string(bss->addr),
			util_ssid_to_utf8(bss->ssid_len, bss->ssid),
			bss->frequency, bss->rank, bss->signal_strength);

	if (!util_ssid_is_utf8(bss->ssid_len, bss->ssid)) {
		l_warn("Ignoring BSS with non-UTF8 SSID");
		return;
	}

	/*
	 * If both an RSN and a WPA elements are present currently
	 * RSN takes priority and the WPA IE is ignored.
	 */
	if (bss->rsne) {
		struct ie_rsn_info rsne;
		int res = ie_parse_rsne_from_data(bss->rsne, bss->rsne[1] + 2,
							&rsne);
		if (res < 0) {
			l_debug("Cannot parse RSN field (%d, %s)",
					res, strerror(-res));
			return;
		}

		security = scan_get_security(bss->capability, &rsne);

		if (security == SECURITY_PSK)
			bss->sha256 =
				rsne.akm_suites & IE_RSN_AKM_SUITE_PSK_SHA256;
		else if (security == SECURITY_8021X)
			bss->sha256 =
				rsne.akm_suites & IE_RSN_AKM_SUITE_8021X_SHA256;
	} else if (bss->wpa) {
		struct ie_rsn_info wpa;
		int res = ie_parse_wpa_from_data(bss->wpa, bss->wpa[1] + 2,
									&wpa);
		if (res < 0) {
			l_debug("Cannot parse WPA IE (%d, %s)",
						res, strerror(-res));
			return;
		}

		security = scan_get_security(bss->capability, &wpa);
	} else
		security = scan_get_security(bss->capability, NULL);

	path = iwd_network_get_path(device, bss->ssid, bss->ssid_len,
					security);

	network = l_hashmap_lookup(device->networks, path);
	if (!network) {
		network = network_create(device, bss->ssid, bss->ssid_len,
						security);

		if (!network_register(network, path)) {
			network_remove(network, -EINVAL);
			return;
		}

		l_hashmap_insert(device->networks,
					network_get_path(network), network);
		l_debug("Added new Network \"%s\" security %s",
			network_get_ssid(network), security_to_str(security));
	}

	if (network_bss_list_isempty(network))
		network_seen(network, timestamp);

	network_bss_add(network, bss);

	/* See if network is autoconnectable (is a known network) */
	if (!network_rankmod(network, &rankmod))
		return;

	entry = l_new(struct autoconnect_entry, 1);
	entry->network = network;
	entry->bss = bss;
	entry->rank = bss->rank * rankmod;
	l_queue_insert(device->autoconnect_list, entry,
				autoconnect_rank_compare, NULL);
}

static bool new_scan_results(uint32_t wiphy_id, uint32_t ifindex,
				struct l_queue *bss_list, void *userdata)
{
	struct device *device = userdata;
	struct network *network;
	const struct l_queue_entry *bss_entry;
	struct timespec now;

	clock_gettime(CLOCK_REALTIME, &now);

	device->old_bss_list = device->bss_list;
	device->bss_list = bss_list;

	while ((network = l_queue_pop_head(device->networks_sorted)))
		network_bss_list_clear(network);

	l_queue_destroy(device->autoconnect_list, l_free);
	device->autoconnect_list = l_queue_new();

	for (bss_entry = l_queue_get_entries(bss_list); bss_entry;
				bss_entry = bss_entry->next) {
		struct scan_bss *bss = bss_entry->data;

		process_bss(device, bss, &now);
	}

	l_hashmap_foreach_remove(device->networks, process_network, device);

	if (device->connected_bss) {
		struct scan_bss *bss;

		bss = l_queue_find(device->bss_list, bss_match,
						device->connected_bss);

		if (!bss) {
			l_warn("Connected BSS not in scan results!");
			l_queue_push_tail(device->bss_list,
						device->connected_bss);
			network_bss_add(device->connected_network,
						device->connected_bss);
			l_queue_remove(device->old_bss_list,
						device->connected_bss);
		} else
			device->connected_bss = bss;
	}

	l_queue_destroy(device->old_bss_list, bss_free);
	device->old_bss_list = NULL;

	if (device->state == DEVICE_STATE_AUTOCONNECT)
		device_autoconnect_next(device);

	return true;
}

struct device *device_create(struct wiphy *wiphy, struct netdev *netdev)
{
	struct device *device;
	struct l_dbus *dbus = dbus_get_bus();
	uint32_t ifindex = netdev_get_ifindex(netdev);

	device = l_new(struct device, 1);
	device->bss_list = l_queue_new();
	device->networks = l_hashmap_new();
	l_hashmap_set_hash_function(device->networks, l_str_hash);
	l_hashmap_set_compare_function(device->networks,
				(l_hashmap_compare_func_t) strcmp);
	device->networks_sorted = l_queue_new();
	device->index = ifindex;
	device->wiphy = wiphy;
	device->netdev = netdev;

	l_queue_push_head(device_list, device);

	if (!l_dbus_object_add_interface(dbus, device_get_path(device),
					IWD_DEVICE_INTERFACE, device))
		l_info("Unable to register %s interface", IWD_DEVICE_INTERFACE);

	__device_watch_call_added(device);

	scan_ifindex_add(device->index);
	device_enter_state(device, DEVICE_STATE_AUTOCONNECT);

	device->eapol_io = eapol_open_pae(device->index);
	if (device->eapol_io)
		l_io_set_read_handler(device->eapol_io, eapol_read,
								device, NULL);
	else
		l_error("Failed to open PAE socket");

	return device;
}

static void device_free(void *user)
{
	struct device *device = user;
	struct l_dbus *dbus;

	l_debug("");

	if (device->scan_pending)
		dbus_pending_reply(&device->scan_pending,
				dbus_error_aborted(device->scan_pending));

	if (device->connect_pending)
		dbus_pending_reply(&device->connect_pending,
				dbus_error_aborted(device->connect_pending));

	__device_watch_call_removed(device);

	dbus = dbus_get_bus();
	l_dbus_unregister_object(dbus, device_get_path(device));

	l_queue_destroy(device->networks_sorted, NULL);
	l_hashmap_destroy(device->networks, network_free);

	l_queue_destroy(device->bss_list, bss_free);
	l_queue_destroy(device->old_bss_list, bss_free);
	l_queue_destroy(device->autoconnect_list, l_free);
	l_io_destroy(device->eapol_io);

	scan_ifindex_remove(device->index);
	l_free(device);
}

void device_remove(struct device *device)
{
	if (!l_queue_remove(device_list, device))
		return;

	device_free(device);
}

struct wiphy *wiphy_find(int wiphy_id)
{
	return l_queue_find(wiphy_list, wiphy_match, L_UINT_TO_PTR(wiphy_id));
}

static void parse_supported_commands(struct wiphy *wiphy,
						struct l_genl_attr *attr)
{
	uint16_t type, len;
	const void *data;

	while (l_genl_attr_next(attr, &type, &len, &data)) {
		uint32_t cmd = *(uint32_t *)data;

		switch (cmd) {
		case NL80211_CMD_START_SCHED_SCAN:
			wiphy->support_scheduled_scan = true;
			break;
		case NL80211_CMD_SET_REKEY_OFFLOAD:
			wiphy->support_rekey_offload = true;
		}
	}
}

static void parse_supported_ciphers(struct wiphy *wiphy, const void *data,
						uint16_t len)
{
	bool s;

	while (len >= 4) {
		uint32_t cipher = *(uint32_t *)data;

		switch (cipher) {
		case CRYPTO_CIPHER_CCMP:
			wiphy->pairwise_ciphers |= IE_RSN_CIPHER_SUITE_CCMP;
			break;
		case CRYPTO_CIPHER_TKIP:
			wiphy->pairwise_ciphers |= IE_RSN_CIPHER_SUITE_TKIP;
			break;
		case CRYPTO_CIPHER_WEP40:
			wiphy->pairwise_ciphers |= IE_RSN_CIPHER_SUITE_WEP40;
			break;
		case CRYPTO_CIPHER_WEP104:
			wiphy->pairwise_ciphers |= IE_RSN_CIPHER_SUITE_WEP104;
			break;
		case CRYPTO_CIPHER_BIP:
			wiphy->pairwise_ciphers |= IE_RSN_CIPHER_SUITE_BIP;
			break;
		default:	/* TODO: Support other ciphers */
			break;
		}

		len -= 4;
		data += 4;
	}

	s = wiphy->pairwise_ciphers & IE_RSN_CIPHER_SUITE_CCMP;
	l_info("Wiphy supports CCMP: %s", s ? "true" : "false");

	s = wiphy->pairwise_ciphers & IE_RSN_CIPHER_SUITE_TKIP;
	l_info("Wiphy supports TKIP: %s", s ? "true" : "false");
}

static void parse_supported_frequencies(struct wiphy *wiphy,
						struct l_genl_attr *freqs)
{
	uint16_t type, len;
	const void *data;
	struct l_genl_attr attr;

	l_debug("");

	while (l_genl_attr_next(freqs, NULL, NULL, NULL)) {
		if (!l_genl_attr_recurse(freqs, &attr))
			continue;

		while (l_genl_attr_next(&attr, &type, &len, &data)) {
			uint32_t u32;

			switch (type) {
			case NL80211_FREQUENCY_ATTR_FREQ:
				u32 = *((uint32_t *) data);
				scan_freq_set_add(wiphy->supported_freqs, u32);
				break;
			}
		}
	}
}

static void parse_supported_bands(struct wiphy *wiphy,
						struct l_genl_attr *bands)
{
	uint16_t type, len;
	const void *data;
	struct l_genl_attr attr;

	l_debug("");

	while (l_genl_attr_next(bands, NULL, NULL, NULL)) {
		if (!l_genl_attr_recurse(bands, &attr))
			continue;

		while (l_genl_attr_next(&attr, &type, &len, &data)) {
			struct l_genl_attr freqs;

			switch (type) {
			case NL80211_BAND_ATTR_FREQS:
				if (!l_genl_attr_recurse(&attr, &freqs))
					continue;

				parse_supported_frequencies(wiphy, &freqs);
				break;
			}
		}
	}
}

#define FAIL_NO_WIPHY()					\
	if (!wiphy) {					\
		l_warn("No wiphy structure found");	\
		return;					\
	}						\

static void wiphy_dump_callback(struct l_genl_msg *msg, void *user_data)
{
	struct wiphy *wiphy = NULL;
	struct l_genl_attr attr, nested;
	uint16_t type, len;
	const void *data;
	uint32_t id;

	if (!l_genl_attr_init(&attr, msg))
		return;

	/*
	 * The wiphy attribute is always the first attribute in the
	 * list. If not then error out with a warning and ignore the
	 * whole message.
	 *
	 * In most cases multiple of these message will be send
	 * since the information included can not fit into a single
	 * message.
	 */
	while (l_genl_attr_next(&attr, &type, &len, &data)) {
		switch (type) {
		case NL80211_ATTR_WIPHY:
			if (wiphy) {
				l_warn("Duplicate wiphy attribute");
				return;
			}

			if (len != sizeof(uint32_t)) {
				l_warn("Invalid wiphy attribute");
				return;
			}

			id = *((uint32_t *) data);

			wiphy = l_queue_find(wiphy_list, wiphy_match,
							L_UINT_TO_PTR(id));
			if (!wiphy) {
				wiphy = l_new(struct wiphy, 1);
				wiphy->id = id;
				wiphy->supported_freqs = scan_freq_set_new();
				l_queue_push_head(wiphy_list, wiphy);
			}
			break;

		case NL80211_ATTR_WIPHY_NAME:
			FAIL_NO_WIPHY();

			if (len > sizeof(wiphy->name)) {
				l_warn("Invalid wiphy name attribute");
				return;
			}

			memcpy(wiphy->name, data, len);
			break;

		case NL80211_ATTR_FEATURE_FLAGS:
			FAIL_NO_WIPHY();

			if (len != sizeof(uint32_t)) {
				l_warn("Invalid feature flags attribute");
				return;
			}

			wiphy->feature_flags = *((uint32_t *) data);
			break;
		case NL80211_ATTR_SUPPORTED_COMMANDS:
			FAIL_NO_WIPHY();

			if (!l_genl_attr_recurse(&attr, &nested))
				return;

			parse_supported_commands(wiphy, &nested);
			break;
		case NL80211_ATTR_CIPHER_SUITES:
			FAIL_NO_WIPHY();

			parse_supported_ciphers(wiphy, data, len);
			break;
		case NL80211_ATTR_WIPHY_BANDS:
			FAIL_NO_WIPHY();

			if (!l_genl_attr_recurse(&attr, &nested))
				return;

			parse_supported_bands(wiphy, &nested);
			break;
		}
	}
}

static void wiphy_dump_done(void *user)
{
	const struct l_queue_entry *wiphy_entry;

	for (wiphy_entry = l_queue_get_entries(wiphy_list); wiphy_entry;
					wiphy_entry = wiphy_entry->next) {
		struct wiphy *wiphy = wiphy_entry->data;
		uint32_t bands;

		l_info("Wiphy: %d, Name: %s", wiphy->id, wiphy->name);
		l_info("Bands:");

		bands = scan_freq_set_get_bands(wiphy->supported_freqs);

		if (bands & SCAN_BAND_2_4_GHZ)
			l_info("\t2.4 Ghz");

		if (bands & SCAN_BAND_5_GHZ)
			l_info("\t5.0 Ghz");
	}
}

static void wiphy_config_notify(struct l_genl_msg *msg, void *user_data)
{
	struct l_genl_attr attr;
	uint16_t type, len;
	const void *data;
	uint8_t cmd;

	cmd = l_genl_msg_get_command(msg);

	l_debug("Notification of command %u", cmd);

	if (!l_genl_attr_init(&attr, msg))
		return;

	switch (cmd) {
	case NL80211_CMD_NEW_WIPHY:
	case NL80211_CMD_DEL_WIPHY:
	{
		const uint32_t *wiphy_id = NULL;
		const char *wiphy_name = NULL;

		while (l_genl_attr_next(&attr, &type, &len, &data)) {
			switch (type) {
			case NL80211_ATTR_WIPHY:
				if (len != sizeof(uint32_t)) {
					l_warn("Invalid wiphy attribute");
					return;
				}

				wiphy_id = data;
				break;

			case NL80211_ATTR_WIPHY_NAME:
				wiphy_name = data;
				break;
			}
		}

		if (!wiphy_id)
			return;

		if (cmd == NL80211_CMD_NEW_WIPHY)
			l_info("New Wiphy %s[%d] added", wiphy_name, *wiphy_id);
		else
			l_info("Wiphy %s[%d] removed", wiphy_name, *wiphy_id);

		break;
	}
	}
}

static void wiphy_regulatory_notify(struct l_genl_msg *msg, void *user_data)
{
	struct l_genl_attr attr;
	uint16_t type, len;
	const void *data;
	uint8_t cmd;

	cmd = l_genl_msg_get_command(msg);

	l_debug("Regulatory notification %u", cmd);

	if (!l_genl_attr_init(&attr, msg))
		return;

	while (l_genl_attr_next(&attr, &type, &len, &data)) {
	}
}

static void regulatory_info_callback(struct l_genl_msg *msg, void *user_data)
{
	struct l_genl_attr attr;
	uint16_t type, len;
	const void *data;

	if (!l_genl_attr_init(&attr, msg))
		return;

	while (l_genl_attr_next(&attr, &type, &len, &data)) {
		switch (type) {
		case NL80211_ATTR_REG_ALPHA2:
			if (len != 3) {
				l_warn("Invalid regulatory alpha2 attribute");
				return;
			}

			l_debug("Regulatory alpha2 is %s", (char *) data);
			break;
		}
	}
}

static void protocol_features_callback(struct l_genl_msg *msg, void *user_data)
{
	struct l_genl_attr attr;
	uint16_t type, len;
	const void *data;
	uint32_t features = 0;

	if (!l_genl_attr_init(&attr, msg))
		return;

	while (l_genl_attr_next(&attr, &type, &len, &data)) {
		switch (type) {
		case NL80211_ATTR_PROTOCOL_FEATURES:
			if (len != sizeof(uint32_t)) {
				l_warn("Invalid protocol features attribute");
				return;
			}

			features = *((uint32_t *) data);
			break;
		}
	}

	if (features & NL80211_PROTOCOL_FEATURE_SPLIT_WIPHY_DUMP)
		l_debug("Found split wiphy dump support");
}

bool wiphy_init(struct l_genl_family *in)
{
	struct l_genl_msg *msg;

	/*
	 * This is an extra sanity check so that no memory is leaked
	 * in case the generic netlink handling gets confused.
	 */
	if (wiphy_list) {
		l_warn("Destroying existing list of wiphy devices");
		l_queue_destroy(wiphy_list, NULL);
	}

	if (!l_dbus_register_interface(dbus_get_bus(),
					IWD_DEVICE_INTERFACE,
					setup_device_interface,
					NULL, true))
		return false;

	nl80211 = in;

	if (!l_genl_family_register(nl80211, "config", wiphy_config_notify,
								NULL, NULL))
		l_error("Registering for config notification failed");

	if (!l_genl_family_register(nl80211, "regulatory",
					wiphy_regulatory_notify, NULL, NULL))
		l_error("Registering for regulatory notification failed");

	wiphy_list = l_queue_new();
	device_list = l_queue_new();

	msg = l_genl_msg_new(NL80211_CMD_GET_PROTOCOL_FEATURES);
	if (!l_genl_family_send(nl80211, msg, protocol_features_callback,
								NULL, NULL))
		l_error("Getting protocol features failed");

	msg = l_genl_msg_new(NL80211_CMD_GET_REG);
	if (!l_genl_family_send(nl80211, msg, regulatory_info_callback,
								NULL, NULL))
		l_error("Getting regulatory info failed");

	msg = l_genl_msg_new(NL80211_CMD_GET_WIPHY);
	if (!l_genl_family_dump(nl80211, msg, wiphy_dump_callback,
						NULL, wiphy_dump_done))
		l_error("Getting all wiphy devices failed");

	return true;
}

bool wiphy_exit(void)
{
	l_queue_destroy(wiphy_list, wiphy_free);
	wiphy_list = NULL;

	l_queue_destroy(device_list, device_free);
	device_list = NULL;

	nl80211 = NULL;

	l_dbus_unregister_interface(dbus_get_bus(), IWD_DEVICE_INTERFACE);

	return true;
}