net/wireless/mesh.c

   1 #include <linux/ieee80211.h>
   2 #include <linux/export.h>
   3 #include <net/cfg80211.h>
   4 #include "nl80211.h"
   5 #include "core.h"
   6
   7 /* Default values, timeouts in ms */
   8 #define MESH_TTL                31
   9 #define MESH_DEFAULT_ELEMENT_TTL 31
  10 #define MESH_MAX_RETR           3
  11 #define MESH_RET_T              100
  12 #define MESH_CONF_T             100
  13 #define MESH_HOLD_T             100
  14
  15 #define MESH_PATH_TIMEOUT       5000
  16 #define MESH_RANN_INTERVAL      5000
  17 #define MESH_PATH_TO_ROOT_TIMEOUT      6000
  18 #define MESH_ROOT_INTERVAL     5000
  19
  20 /*
  21  * Minimum interval between two consecutive PREQs originated by the same
  22  * interface
  23  */
  24 #define MESH_PREQ_MIN_INT       10
  25 #define MESH_PERR_MIN_INT       100
  26 #define MESH_DIAM_TRAVERSAL_TIME 50
  27
  28 #define MESH_RSSI_THRESHOLD     0
  29
  30 /*
  31  * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
  32  * before timing out.  This way it will remain ACTIVE and no data frames
  33  * will be unnecessarily held in the pending queue.
  34  */
  35 #define MESH_PATH_REFRESH_TIME                  1000
  36 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
  37
  38 /* Default maximum number of established plinks per interface */
  39 #define MESH_MAX_ESTAB_PLINKS   32
  40
  41 #define MESH_MAX_PREQ_RETRIES   4
  42
  43 #define MESH_SYNC_NEIGHBOR_OFFSET_MAX 50
  44
  45 const struct mesh_config default_mesh_config = {
  46         .dot11MeshRetryTimeout = MESH_RET_T,
  47         .dot11MeshConfirmTimeout = MESH_CONF_T,
  48         .dot11MeshHoldingTimeout = MESH_HOLD_T,
  49         .dot11MeshMaxRetries = MESH_MAX_RETR,
  50         .dot11MeshTTL = MESH_TTL,
  51         .element_ttl = MESH_DEFAULT_ELEMENT_TTL,
  52         .auto_open_plinks = true,
  53         .dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
  54         .dot11MeshNbrOffsetMaxNeighbor = MESH_SYNC_NEIGHBOR_OFFSET_MAX,
  55         .dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
  56         .dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
  57         .dot11MeshHWMPperrMinInterval = MESH_PERR_MIN_INT,
  58         .dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
  59         .dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
  60         .path_refresh_time = MESH_PATH_REFRESH_TIME,
  61         .min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
  62         .dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL,
  63         .dot11MeshGateAnnouncementProtocol = false,
  64         .dot11MeshForwarding = true,
  65         .rssi_threshold = MESH_RSSI_THRESHOLD,
  66         .ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED,
  67         .dot11MeshHWMPactivePathToRootTimeout = MESH_PATH_TO_ROOT_TIMEOUT,
  68         .dot11MeshHWMProotInterval = MESH_ROOT_INTERVAL,
  69 };
  70
  71 const struct mesh_setup default_mesh_setup = {
  72         /* cfg80211_join_mesh() will pick a channel if needed */
  73         .channel = NULL,
  74         .channel_type = NL80211_CHAN_NO_HT,
  75         .sync_method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET,
  76         .path_sel_proto = IEEE80211_PATH_PROTOCOL_HWMP,
  77         .path_metric = IEEE80211_PATH_METRIC_AIRTIME,
  78         .ie = NULL,
  79         .ie_len = 0,
  80         .is_secure = false,
  81 };
  82
  83 int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
  84                          struct net_device *dev,
  85                          struct mesh_setup *setup,
  86                          const struct mesh_config *conf)
  87 {
  88         struct wireless_dev *wdev = dev->ieee80211_ptr;
  89         int err;
  90
  91         BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
  92
  93         ASSERT_WDEV_LOCK(wdev);
  94
  95         if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
  96                 return -EOPNOTSUPP;
  97
  98         if (!(rdev->wiphy.flags & WIPHY_FLAG_MESH_AUTH) &&
  99               setup->is_secure)
 100                 return -EOPNOTSUPP;
 101
 102         if (wdev->mesh_id_len)
 103                 return -EALREADY;
 104
 105         if (!setup->mesh_id_len)
 106                 return -EINVAL;
 107
 108         if (!rdev->ops->join_mesh)
 109                 return -EOPNOTSUPP;
 110
 111         if (!setup->channel) {
 112                 /* if no channel explicitly given, use preset channel */
 113                 setup->channel = wdev->preset_chan;
 114                 setup->channel_type = wdev->preset_chantype;
 115         }
 116
 117         if (!setup->channel) {
 118                 /* if we don't have that either, use the first usable channel */
 119                 enum ieee80211_band band;
 120
 121                 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 122                         struct ieee80211_supported_band *sband;
 123                         struct ieee80211_channel *chan;
 124                         int i;
 125
 126                         sband = rdev->wiphy.bands[band];
 127                         if (!sband)
 128                                 continue;
 129
 130                         for (i = 0; i < sband->n_channels; i++) {
 131                                 chan = &sband->channels[i];
 132                                 if (chan->flags & (IEEE80211_CHAN_NO_IBSS |
 133                                                    IEEE80211_CHAN_PASSIVE_SCAN |
 134                                                    IEEE80211_CHAN_DISABLED |
 135                                                    IEEE80211_CHAN_RADAR))
 136                                         continue;
 137                                 setup->channel = chan;
 138                                 break;
 139                         }
 140
 141                         if (setup->channel)
 142                                 break;
 143                 }
 144
 145                 /* no usable channel ... */
 146                 if (!setup->channel)
 147                         return -EINVAL;
 148
 149                 setup->channel_type = NL80211_CHAN_NO_HT;
 150         }
 151
 152         if (!cfg80211_can_beacon_sec_chan(&rdev->wiphy, setup->channel,
 153                                           setup->channel_type))
 154                 return -EINVAL;
 155
 156         err = rdev->ops->join_mesh(&rdev->wiphy, dev, conf, setup);
 157         if (!err) {
 158                 memcpy(wdev->ssid, setup->mesh_id, setup->mesh_id_len);
 159                 wdev->mesh_id_len = setup->mesh_id_len;
 160         }
 161
 162         return err;
 163 }
 164
 165 int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 166                        struct net_device *dev,
 167                        struct mesh_setup *setup,
 168                        const struct mesh_config *conf)
 169 {
 170         struct wireless_dev *wdev = dev->ieee80211_ptr;
 171         int err;
 172
 173         wdev_lock(wdev);
 174         err = __cfg80211_join_mesh(rdev, dev, setup, conf);
 175         wdev_unlock(wdev);
 176
 177         return err;
 178 }
 179
 180 int cfg80211_set_mesh_freq(struct cfg80211_registered_device *rdev,
 181                            struct wireless_dev *wdev, int freq,
 182                            enum nl80211_channel_type channel_type)
 183 {
 184         struct ieee80211_channel *channel;
 185
 186         channel = rdev_freq_to_chan(rdev, freq, channel_type);
 187         if (!channel || !cfg80211_can_beacon_sec_chan(&rdev->wiphy,
 188                                                       channel,
 189                                                       channel_type)) {
 190                 return -EINVAL;
 191         }
 192
 193         /*
 194          * Workaround for libertas (only!), it puts the interface
 195          * into mesh mode but doesn't implement join_mesh. Instead,
 196          * it is configured via sysfs and then joins the mesh when
 197          * you set the channel. Note that the libertas mesh isn't
 198          * compatible with 802.11 mesh.
 199          */
 200         if (rdev->ops->libertas_set_mesh_channel) {
 201                 if (channel_type != NL80211_CHAN_NO_HT)
 202                         return -EINVAL;
 203
 204                 if (!netif_running(wdev->netdev))
 205                         return -ENETDOWN;
 206                 return rdev->ops->libertas_set_mesh_channel(&rdev->wiphy,
 207                                                             wdev->netdev,
 208                                                             channel);
 209         }
 210
 211         if (wdev->mesh_id_len)
 212                 return -EBUSY;
 213
 214         wdev->preset_chan = channel;
 215         wdev->preset_chantype = channel_type;
 216         return 0;
 217 }
 218
 219 void cfg80211_notify_new_peer_candidate(struct net_device *dev,
 220                 const u8 *macaddr, const u8* ie, u8 ie_len, gfp_t gfp)
 221 {
 222         struct wireless_dev *wdev = dev->ieee80211_ptr;
 223
 224         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_MESH_POINT))
 225                 return;
 226
 227         nl80211_send_new_peer_candidate(wiphy_to_dev(wdev->wiphy), dev,
 228                         macaddr, ie, ie_len, gfp);
 229 }
 230 EXPORT_SYMBOL(cfg80211_notify_new_peer_candidate);
 231
 232 static int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
 233                                  struct net_device *dev)
 234 {
 235         struct wireless_dev *wdev = dev->ieee80211_ptr;
 236         int err;
 237
 238         ASSERT_WDEV_LOCK(wdev);
 239
 240         if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
 241                 return -EOPNOTSUPP;
 242
 243         if (!rdev->ops->leave_mesh)
 244                 return -EOPNOTSUPP;
 245
 246         if (!wdev->mesh_id_len)
 247                 return -ENOTCONN;
 248
 249         err = rdev->ops->leave_mesh(&rdev->wiphy, dev);
 250         if (!err)
 251                 wdev->mesh_id_len = 0;
 252         return err;
 253 }
 254
 255 int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
 256                         struct net_device *dev)
 257 {
 258         struct wireless_dev *wdev = dev->ieee80211_ptr;
 259         int err;
 260
 261         wdev_lock(wdev);
 262         err = __cfg80211_leave_mesh(rdev, dev);
 263         wdev_unlock(wdev);
 264
 265         return err;
 266 }