path: root/net/wireless/sme.c

// SPDX-License-Identifier: GPL-2.0
/*
 * SME code for cfg80211
 * both driver SME event handling and the SME implementation
 * (for nl80211's connect() and wext)
 *
 * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
 * Copyright (C) 2009, 2020, 2022-2025 Intel Corporation. All rights reserved.
 * Copyright 2017	Intel Deutschland GmbH
 */

#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/wireless.h>
#include <linux/export.h>
#include <net/iw_handler.h>
#include <net/cfg80211.h>
#include <net/rtnetlink.h>
#include "nl80211.h"
#include "reg.h"
#include "rdev-ops.h"

/*
 * Software SME in cfg80211, using auth/assoc/deauth calls to the
 * driver. This is for implementing nl80211's connect/disconnect
 * and wireless extensions (if configured.)
 */

struct cfg80211_conn {
	struct cfg80211_connect_params params;
	/* these are sub-states of the _CONNECTING sme_state */
	enum {
		CFG80211_CONN_SCANNING,
		CFG80211_CONN_SCAN_AGAIN,
		CFG80211_CONN_AUTHENTICATE_NEXT,
		CFG80211_CONN_AUTHENTICATING,
		CFG80211_CONN_AUTH_FAILED_TIMEOUT,
		CFG80211_CONN_ASSOCIATE_NEXT,
		CFG80211_CONN_ASSOCIATING,
		CFG80211_CONN_ASSOC_FAILED,
		CFG80211_CONN_ASSOC_FAILED_TIMEOUT,
		CFG80211_CONN_DEAUTH,
		CFG80211_CONN_ABANDON,
		CFG80211_CONN_CONNECTED,
	} state;
	u8 bssid[ETH_ALEN], prev_bssid[ETH_ALEN];
	const u8 *ie;
	size_t ie_len;
	bool auto_auth, prev_bssid_valid;
};

static void cfg80211_sme_free(struct wireless_dev *wdev)
{
	if (!wdev->conn)
		return;

	kfree(wdev->conn->ie);
	kfree(wdev->conn);
	wdev->conn = NULL;
}

static int cfg80211_conn_scan(struct wireless_dev *wdev)
{
	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
	struct cfg80211_scan_request_int *request;
	int n_channels, err;

	lockdep_assert_wiphy(wdev->wiphy);

	if (rdev->scan_req || rdev->scan_msg)
		return -EBUSY;

	if (wdev->conn->params.channel)
		n_channels = 1;
	else
		n_channels = ieee80211_get_num_supported_channels(wdev->wiphy);

	request = kzalloc(sizeof(*request) + sizeof(request->req.ssids[0]) +
			  sizeof(request->req.channels[0]) * n_channels,
			  GFP_KERNEL);
	if (!request)
		return -ENOMEM;

	if (wdev->conn->params.channel) {
		enum nl80211_band band = wdev->conn->params.channel->band;
		struct ieee80211_supported_band *sband =
			wdev->wiphy->bands[band];

		if (!sband) {
			kfree(request);
			return -EINVAL;
		}
		request->req.channels[0] = wdev->conn->params.channel;
		request->req.rates[band] = (1 << sband->n_bitrates) - 1;
	} else {
		int i = 0, j;
		enum nl80211_band band;
		struct ieee80211_supported_band *bands;
		struct ieee80211_channel *channel;

		for (band = 0; band < NUM_NL80211_BANDS; band++) {
			bands = wdev->wiphy->bands[band];
			if (!bands)
				continue;
			for (j = 0; j < bands->n_channels; j++) {
				channel = &bands->channels[j];
				if (channel->flags & IEEE80211_CHAN_DISABLED)
					continue;
				request->req.channels[i++] = channel;
			}
			request->req.rates[band] = (1 << bands->n_bitrates) - 1;
		}
		n_channels = i;
	}
	request->req.n_channels = n_channels;
	request->req.ssids = (void *)request +
			     struct_size(request, req.channels, n_channels);
	request->req.n_ssids = 1;

	memcpy(request->req.ssids[0].ssid, wdev->conn->params.ssid,
	       wdev->conn->params.ssid_len);
	request->req.ssids[0].ssid_len = wdev->conn->params.ssid_len;

	eth_broadcast_addr(request->req.bssid);

	request->req.wdev = wdev;
	request->req.wiphy = &rdev->wiphy;
	request->req.scan_start = jiffies;

	rdev->scan_req = request;

	err = cfg80211_scan(rdev);
	if (!err) {
		wdev->conn->state = CFG80211_CONN_SCANNING;
		nl80211_send_scan_start(rdev, wdev);
		dev_hold(wdev->netdev);
	} else {
		rdev->scan_req = NULL;
		kfree(request);
	}
	return err;
}

static int cfg80211_conn_do_work(struct wireless_dev *wdev,
				 enum nl80211_timeout_reason *treason)
{
	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
	struct cfg80211_connect_params *params;
	struct cfg80211_auth_request auth_req = {};
	struct cfg80211_assoc_request req = {};
	int err;

	lockdep_assert_wiphy(wdev->wiphy);

	if (!wdev->conn)
		return 0;

	params = &wdev->conn->params;

	switch (wdev->conn->state) {
	case CFG80211_CONN_SCANNING:
		/* didn't find it during scan ... */
		return -ENOENT;
	case CFG80211_CONN_SCAN_AGAIN:
		return cfg80211_conn_scan(wdev);
	case CFG80211_CONN_AUTHENTICATE_NEXT:
		if (WARN_ON(!rdev->ops->auth))
			return -EOPNOTSU