linux/net/wireless/mesh.c
Johannes Berg 7b0a0e3c3a wifi: cfg80211: do some rework towards MLO link APIs
In order to support multi-link operation with multiple links,
start adding some APIs. The notable addition here is to have
the link ID in a new nl80211 attribute, that will be used to
differentiate the links in many nl80211 operations.

So far, this patch adds the netlink NL80211_ATTR_MLO_LINK_ID
attribute (as well as the NL80211_ATTR_MLO_LINKS attribute)
and plugs it through the system in some places, checking the
validity etc. along with other infrastructure needed for it.

For now, I've decided to include only the over-the-air link
ID in the API. I know we discussed that we eventually need to
have to have other ways of identifying a link, but for local
AP mode and auth/assoc commands as well as set_key etc. we'll
use the OTA ID.

Also included in this patch is some refactoring of the data
structures in struct wireless_dev, splitting for the first
time the data into type dependent pieces, to make reasoning
about these things easier.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2022-06-20 12:54:58 +02:00

303 lines
8.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Portions
* Copyright (C) 2022 Intel Corporation
*/
#include <linux/ieee80211.h>
#include <linux/export.h>
#include <net/cfg80211.h>
#include "nl80211.h"
#include "core.h"
#include "rdev-ops.h"
/* Default values, timeouts in ms */
#define MESH_TTL 31
#define MESH_DEFAULT_ELEMENT_TTL 31
#define MESH_MAX_RETR 3
#define MESH_RET_T 100
#define MESH_CONF_T 100
#define MESH_HOLD_T 100
#define MESH_PATH_TIMEOUT 5000
#define MESH_RANN_INTERVAL 5000
#define MESH_PATH_TO_ROOT_TIMEOUT 6000
#define MESH_ROOT_INTERVAL 5000
#define MESH_ROOT_CONFIRMATION_INTERVAL 2000
#define MESH_DEFAULT_PLINK_TIMEOUT 1800 /* timeout in seconds */
/*
* Minimum interval between two consecutive PREQs originated by the same
* interface
*/
#define MESH_PREQ_MIN_INT 10
#define MESH_PERR_MIN_INT 100
#define MESH_DIAM_TRAVERSAL_TIME 50
#define MESH_RSSI_THRESHOLD 0
/*
* A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
* before timing out. This way it will remain ACTIVE and no data frames
* will be unnecessarily held in the pending queue.
*/
#define MESH_PATH_REFRESH_TIME 1000
#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
/* Default maximum number of established plinks per interface */
#define MESH_MAX_ESTAB_PLINKS 32
#define MESH_MAX_PREQ_RETRIES 4
#define MESH_SYNC_NEIGHBOR_OFFSET_MAX 50
#define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units (=TUs) */
#define MESH_DEFAULT_DTIM_PERIOD 2
#define MESH_DEFAULT_AWAKE_WINDOW 10 /* in 1024 us units (=TUs) */
const struct mesh_config default_mesh_config = {
.dot11MeshRetryTimeout = MESH_RET_T,
.dot11MeshConfirmTimeout = MESH_CONF_T,
.dot11MeshHoldingTimeout = MESH_HOLD_T,
.dot11MeshMaxRetries = MESH_MAX_RETR,
.dot11MeshTTL = MESH_TTL,
.element_ttl = MESH_DEFAULT_ELEMENT_TTL,
.auto_open_plinks = true,
.dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
.dot11MeshNbrOffsetMaxNeighbor = MESH_SYNC_NEIGHBOR_OFFSET_MAX,
.dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
.dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
.dot11MeshHWMPperrMinInterval = MESH_PERR_MIN_INT,
.dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
.dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
.path_refresh_time = MESH_PATH_REFRESH_TIME,
.min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
.dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL,
.dot11MeshGateAnnouncementProtocol = false,
.dot11MeshForwarding = true,
.rssi_threshold = MESH_RSSI_THRESHOLD,
.ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED,
.dot11MeshHWMPactivePathToRootTimeout = MESH_PATH_TO_ROOT_TIMEOUT,
.dot11MeshHWMProotInterval = MESH_ROOT_INTERVAL,
.dot11MeshHWMPconfirmationInterval = MESH_ROOT_CONFIRMATION_INTERVAL,
.power_mode = NL80211_MESH_POWER_ACTIVE,
.dot11MeshAwakeWindowDuration = MESH_DEFAULT_AWAKE_WINDOW,
.plink_timeout = MESH_DEFAULT_PLINK_TIMEOUT,
.dot11MeshNolearn = false,
};
const struct mesh_setup default_mesh_setup = {
/* cfg80211_join_mesh() will pick a channel if needed */
.sync_method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET,
.path_sel_proto = IEEE80211_PATH_PROTOCOL_HWMP,
.path_metric = IEEE80211_PATH_METRIC_AIRTIME,
.auth_id = 0, /* open */
.ie = NULL,
.ie_len = 0,
.is_secure = false,
.user_mpm = false,
.beacon_interval = MESH_DEFAULT_BEACON_INTERVAL,
.dtim_period = MESH_DEFAULT_DTIM_PERIOD,
};
int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
struct net_device *dev,
struct mesh_setup *setup,
const struct mesh_config *conf)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
ASSERT_WDEV_LOCK(wdev);
if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
return -EOPNOTSUPP;
if (!(rdev->wiphy.flags & WIPHY_FLAG_MESH_AUTH) &&
setup->is_secure)
return -EOPNOTSUPP;
if (wdev->u.mesh.id_len)
return -EALREADY;
if (!setup->mesh_id_len)
return -EINVAL;
if (!rdev->ops->join_mesh)
return -EOPNOTSUPP;
if (!setup->chandef.chan) {
/* if no channel explicitly given, use preset channel */
setup->chandef = wdev->u.mesh.preset_chandef;
}
if (!setup->chandef.chan) {
/* if we don't have that either, use the first usable channel */
enum nl80211_band band;
for (band = 0; band < NUM_NL80211_BANDS; band++) {
struct ieee80211_supported_band *sband;
struct ieee80211_channel *chan;
int i;
sband = rdev->wiphy.bands[band];
if (!sband)
continue;
for (i = 0; i < sband->n_channels; i++) {
chan = &sband->channels[i];
if (chan->flags & (IEEE80211_CHAN_NO_IR |
IEEE80211_CHAN_DISABLED |
IEEE80211_CHAN_RADAR))
continue;
setup->chandef.chan = chan;
break;
}
if (setup->chandef.chan)
break;
}
/* no usable channel ... */
if (!setup->chandef.chan)
return -EINVAL;
setup->chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
setup->chandef.center_freq1 = setup->chandef.chan->center_freq;
}
/*
* check if basic rates are available otherwise use mandatory rates as
* basic rates
*/
if (!setup->basic_rates) {
enum nl80211_bss_scan_width scan_width;
struct ieee80211_supported_band *sband =
rdev->wiphy.bands[setup->chandef.chan->band];
if (setup->chandef.chan->band == NL80211_BAND_2GHZ) {
int i;
/*
* Older versions selected the mandatory rates for
* 2.4 GHz as well, but were broken in that only
* 1 Mbps was regarded as a mandatory rate. Keep
* using just 1 Mbps as the default basic rate for
* mesh to be interoperable with older versions.
*/
for (i = 0; i < sband->n_bitrates; i++) {
if (sband->bitrates[i].bitrate == 10) {
setup->basic_rates = BIT(i);
break;
}
}
} else {
scan_width = cfg80211_chandef_to_scan_width(&setup->chandef);
setup->basic_rates = ieee80211_mandatory_rates(sband,
scan_width);
}
}
err = cfg80211_chandef_dfs_required(&rdev->wiphy,
&setup->chandef,
NL80211_IFTYPE_MESH_POINT);
if (err < 0)
return err;
if (err > 0 && !setup->userspace_handles_dfs)
return -EINVAL;
if (!cfg80211_reg_can_beacon(&rdev->wiphy, &setup->chandef,
NL80211_IFTYPE_MESH_POINT))
return -EINVAL;
err = rdev_join_mesh(rdev, dev, conf, setup);
if (!err) {
memcpy(wdev->u.mesh.id, setup->mesh_id, setup->mesh_id_len);
wdev->u.mesh.id_len = setup->mesh_id_len;
wdev->u.mesh.chandef = setup->chandef;
wdev->u.mesh.beacon_interval = setup->beacon_interval;
}
return err;
}
int cfg80211_set_mesh_channel(struct cfg80211_registered_device *rdev,
struct wireless_dev *wdev,
struct cfg80211_chan_def *chandef)
{
int err;
/*
* Workaround for libertas (only!), it puts the interface
* into mesh mode but doesn't implement join_mesh. Instead,
* it is configured via sysfs and then joins the mesh when
* you set the channel. Note that the libertas mesh isn't
* compatible with 802.11 mesh.
*/
if (rdev->ops->libertas_set_mesh_channel) {
if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
return -EINVAL;
if (!netif_running(wdev->netdev))
return -ENETDOWN;
err = rdev_libertas_set_mesh_channel(rdev, wdev->netdev,
chandef->chan);
if (!err)
wdev->u.mesh.chandef = *chandef;
return err;
}
if (wdev->u.mesh.id_len)
return -EBUSY;
wdev->u.mesh.preset_chandef = *chandef;
return 0;
}
int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
struct net_device *dev)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
ASSERT_WDEV_LOCK(wdev);
if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
return -EOPNOTSUPP;
if (!rdev->ops->leave_mesh)
return -EOPNOTSUPP;
if (!wdev->u.mesh.id_len)
return -ENOTCONN;
err = rdev_leave_mesh(rdev, dev);
if (!err) {
wdev->conn_owner_nlportid = 0;
wdev->u.mesh.id_len = 0;
wdev->u.mesh.beacon_interval = 0;
memset(&wdev->u.mesh.chandef, 0,
sizeof(wdev->u.mesh.chandef));
rdev_set_qos_map(rdev, dev, NULL);
cfg80211_sched_dfs_chan_update(rdev);
}
return err;
}
int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
struct net_device *dev)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
wdev_lock(wdev);
err = __cfg80211_leave_mesh(rdev, dev);
wdev_unlock(wdev);
return err;
}