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 #define MESH_ROOT_CONFIRMATION_INTERVAL 2000
  20
  21 /*
  22  * Minimum interval between two consecutive PREQs originated by the same
  23  * interface
  24  */
  25 #define MESH_PREQ_MIN_INT       10
  26 #define MESH_PERR_MIN_INT       100
  27 #define MESH_DIAM_TRAVERSAL_TIME 50
  28
  29 #define MESH_RSSI_THRESHOLD     0
  30
  31 /*
  32  * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
  33  * before timing out.  This way it will remain ACTIVE and no data frames
  34  * will be unnecessarily held in the pending queue.
  35  */
  36 #define MESH_PATH_REFRESH_TIME                  1000
  37 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
  38
  39 /* Default maximum number of established plinks per interface */
  40 #define MESH_MAX_ESTAB_PLINKS   32
  41
  42 #define MESH_MAX_PREQ_RETRIES   4
  43
  44 #define MESH_SYNC_NEIGHBOR_OFFSET_MAX 50
  45
  46 const struct mesh_config default_mesh_config = {
  47         .dot11MeshRetryTimeout = MESH_RET_T,
  48         .dot11MeshConfirmTimeout = MESH_CONF_T,
  49         .dot11MeshHoldingTimeout = MESH_HOLD_T,
  50         .dot11MeshMaxRetries = MESH_MAX_RETR,
  51         .dot11MeshTTL = MESH_TTL,
  52         .element_ttl = MESH_DEFAULT_ELEMENT_TTL,
  53         .auto_open_plinks = true,
  54         .dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
  55         .dot11MeshNbrOffsetMaxNeighbor = MESH_SYNC_NEIGHBOR_OFFSET_MAX,
  56         .dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
  57         .dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
  58         .dot11MeshHWMPperrMinInterval = MESH_PERR_MIN_INT,
  59         .dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
  60         .dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
  61         .path_refresh_time = MESH_PATH_REFRESH_TIME,
  62         .min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
  63         .dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL,
  64         .dot11MeshGateAnnouncementProtocol = false,
  65         .dot11MeshForwarding = true,
  66         .rssi_threshold = MESH_RSSI_THRESHOLD,
  67         .ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED,
  68         .dot11MeshHWMPactivePathToRootTimeout = MESH_PATH_TO_ROOT_TIMEOUT,
  69         .dot11MeshHWMProotInterval = MESH_ROOT_INTERVAL,
  70         .dot11MeshHWMPconfirmationInterval = MESH_ROOT_CONFIRMATION_INTERVAL,
  71 };
  72
  73 const struct mesh_setup default_mesh_setup = {
  74         /* cfg80211_join_mesh() will pick a channel if needed */
  75         .channel = NULL,
  76         .channel_type = NL80211_CHAN_NO_HT,
  77         .sync_method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET,
  78         .path_sel_proto = IEEE80211_PATH_PROTOCOL_HWMP,
  79         .path_metric = IEEE80211_PATH_METRIC_AIRTIME,
  80         .ie = NULL,
  81         .ie_len = 0,
  82         .is_secure = false,
  83 };
  84
  85 int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
  86                          struct net_device *dev,
  87                          struct mesh_setup *setup,
  88                          const struct mesh_config *conf)
  89 {
  90         struct wireless_dev *wdev = dev->ieee80211_ptr;
  91         int err;
  92
  93         BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
  94
  95         ASSERT_WDEV_LOCK(wdev);
  96
  97         if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
  98                 return -EOPNOTSUPP;
  99
 100         if (!(rdev->wiphy.flags & WIPHY_FLAG_MESH_AUTH) &&
 101               setup->is_secure)
 102                 return -EOPNOTSUPP;
 103
 104         if (wdev->mesh_id_len)
 105                 return -EALREADY;
 106
 107         if (!setup->mesh_id_len)
 108                 return -EINVAL;
 109
 110         if (!rdev->ops->join_mesh)
 111                 return -EOPNOTSUPP;
 112
 113         if (!setup->channel) {
 114                 /* if no channel explicitly given, use preset channel */
 115                 setup->channel = wdev->preset_chan;
 116                 setup->channel_type = wdev->preset_chantype;
 117         }
 118
 119         if (!setup->channel) {
 120                 /* if we don't have that either, use the first usable channel */
 121                 enum ieee80211_band band;
 122
 123                 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 124                         struct ieee80211_supported_band *sband;
 125                         struct ieee80211_channel *chan;
 126                         int i;
 127
 128                         sband = rdev->wiphy.bands[band];
 129                         if (!sband)
 130                                 continue;
 131
 132                         for (i = 0; i < sband->n_channels; i++) {
 133                                 chan = &sband->channels[i];
 134                                 if (chan->flags & (IEEE80211_CHAN_NO_IBSS |
 135                                                    IEEE80211_CHAN_PASSIVE_SCAN |
 136                                                    IEEE80211_CHAN_DISABLED |
 137                                                    IEEE80211_CHAN_RADAR))
 138                                         continue;
 139                                 setup->channel = chan;
 140                                 break;
 141                         }
 142
 143                         if (setup->channel)
 144                                 break;
 145                 }
 146
 147                 /* no usable channel ... */
 148                 if (!setup->channel)
 149                         return -EINVAL;
 150
 151                 setup->channel_type = NL80211_CHAN_NO_HT;
 152         }
 153
 154         if (!cfg80211_can_beacon_sec_chan(&rdev->wiphy, setup->channel,
 155                                           setup->channel_type))
 156                 return -EINVAL;
 157
 158         err = rdev->ops->join_mesh(&rdev->wiphy, dev, conf, setup);
 159         if (!err) {
 160                 memcpy(wdev->ssid, setup->mesh_id, setup->mesh_id_len);
 161                 wdev->mesh_id_len = setup->mesh_id_len;
 162         }
 163
 164         return err;
 165 }
 166
 167 int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 168                        struct net_device *dev,
 169                        struct mesh_setup *setup,
 170                        const struct mesh_config *conf)
 171 {
 172         struct wireless_dev *wdev = dev->ieee80211_ptr;
 173         int err;
 174
 175         wdev_lock(wdev);
 176         err = __cfg80211_join_mesh(rdev, dev, setup, conf);
 177         wdev_unlock(wdev);
 178
 179         return err;
 180 }
 181
 182 int cfg80211_set_mesh_freq(struct cfg80211_registered_device *rdev,
 183                            struct wireless_dev *wdev, int freq,
 184                            enum nl80211_channel_type channel_type)
 185 {
 186         struct ieee80211_channel *channel;
 187
 188         channel = rdev_freq_to_chan(rdev, freq, channel_type);
 189         if (!channel || !cfg80211_can_beacon_sec_chan(&rdev->wiphy,
 190                                                       channel,
 191                                                       channel_type)) {
 192                 return -EINVAL;
 193         }
 194
 195         /*
 196          * Workaround for libertas (only!), it puts the interface
 197          * into mesh mode but doesn't implement join_mesh. Instead,
 198          * it is configured via sysfs and then joins the mesh when
 199          * you set the channel. Note that the libertas mesh isn't
 200          * compatible with 802.11 mesh.
 201          */
 202         if (rdev->ops->libertas_set_mesh_channel) {
 203                 if (channel_type != NL80211_CHAN_NO_HT)
 204                         return -EINVAL;
 205
 206                 if (!netif_running(wdev->netdev))
 207                         return -ENETDOWN;
 208                 return rdev->ops->libertas_set_mesh_channel(&rdev->wiphy,
 209                                                             wdev->netdev,
 210                                                             channel);
 211         }
 212
 213         if (wdev->mesh_id_len)
 214                 return -EBUSY;
 215
 216         wdev->preset_chan = channel;
 217         wdev->preset_chantype = channel_type;
 218         return 0;
 219 }
 220
 221 void cfg80211_notify_new_peer_candidate(struct net_device *dev,
 222                 const u8 *macaddr, const u8* ie, u8 ie_len, gfp_t gfp)
 223 {
 224         struct wireless_dev *wdev = dev->ieee80211_ptr;
 225
 226         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_MESH_POINT))
 227                 return;
 228
 229         nl80211_send_new_peer_candidate(wiphy_to_dev(wdev->wiphy), dev,
 230                         macaddr, ie, ie_len, gfp);
 231 }
 232 EXPORT_SYMBOL(cfg80211_notify_new_peer_candidate);
 233
 234 static int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
 235                                  struct net_device *dev)
 236 {
 237         struct wireless_dev *wdev = dev->ieee80211_ptr;
 238         int err;
 239
 240         ASSERT_WDEV_LOCK(wdev);
 241
 242         if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
 243                 return -EOPNOTSUPP;
 244
 245         if (!rdev->ops->leave_mesh)
 246                 return -EOPNOTSUPP;
 247
 248         if (!wdev->mesh_id_len)
 249                 return -ENOTCONN;
 250
 251         err = rdev->ops->leave_mesh(&rdev->wiphy, dev);
 252         if (!err)
 253                 wdev->mesh_id_len = 0;
 254         return err;
 255 }
 256
 257 int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
 258                         struct net_device *dev)
 259 {
 260         struct wireless_dev *wdev = dev->ieee80211_ptr;
 261         int err;
 262
 263         wdev_lock(wdev);
 264         err = __cfg80211_leave_mesh(rdev, dev);
 265         wdev_unlock(wdev);
 266
 267         return err;
 268 }