net/mac80211/iface.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/if_arp.h>
  13 #include <linux/netdevice.h>
  14 #include <linux/rtnetlink.h>
  15 #include <net/mac80211.h>
  16 #include "ieee80211_i.h"
  17 #include "sta_info.h"
  18 #include "debugfs_netdev.h"
  19 #include "mesh.h"
  20
  21 /*
  22  * Called when the netdev is removed or, by the code below, before
  23  * the interface type changes.
  24  */
  25 static void ieee80211_teardown_sdata(struct net_device *dev)
  26 {
  27         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  28         struct ieee80211_local *local = sdata->local;
  29         struct beacon_data *beacon;
  30         struct sk_buff *skb;
  31         int flushed;
  32         int i;
  33
  34         ieee80211_debugfs_remove_netdev(sdata);
  35
  36         /* free extra data */
  37         ieee80211_free_keys(sdata);
  38
  39         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
  40                 __skb_queue_purge(&sdata->fragments[i].skb_list);
  41         sdata->fragment_next = 0;
  42
  43         switch (sdata->vif.type) {
  44         case IEEE80211_IF_TYPE_AP:
  45                 beacon = sdata->u.ap.beacon;
  46                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
  47                 synchronize_rcu();
  48                 kfree(beacon);
  49
  50                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
  51                         local->total_ps_buffered--;
  52                         dev_kfree_skb(skb);
  53                 }
  54
  55                 break;
  56         case IEEE80211_IF_TYPE_MESH_POINT:
  57                 /* Allow compiler to elide mesh_rmc_free call. */
  58                 if (ieee80211_vif_is_mesh(&sdata->vif))
  59                         mesh_rmc_free(dev);
  60                 /* fall through */
  61         case IEEE80211_IF_TYPE_STA:
  62         case IEEE80211_IF_TYPE_IBSS:
  63                 kfree(sdata->u.sta.extra_ie);
  64                 kfree(sdata->u.sta.assocreq_ies);
  65                 kfree(sdata->u.sta.assocresp_ies);
  66                 kfree_skb(sdata->u.sta.probe_resp);
  67                 break;
  68         case IEEE80211_IF_TYPE_WDS:
  69         case IEEE80211_IF_TYPE_VLAN:
  70         case IEEE80211_IF_TYPE_MNTR:
  71                 break;
  72         case IEEE80211_IF_TYPE_INVALID:
  73                 BUG();
  74                 break;
  75         }
  76
  77         flushed = sta_info_flush(local, sdata);
  78         WARN_ON(flushed);
  79 }
  80
  81 /*
  82  * Helper function to initialise an interface to a specific type.
  83  */
  84 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
  85                                   enum ieee80211_if_types type)
  86 {
  87         struct ieee80211_if_sta *ifsta;
  88
  89         /* clear type-dependent union */
  90         memset(&sdata->u, 0, sizeof(sdata->u));
  91
  92         /* and set some type-dependent values */
  93         sdata->vif.type = type;
  94
  95         /* only monitor differs */
  96         sdata->dev->type = ARPHRD_ETHER;
  97
  98         switch (type) {
  99         case IEEE80211_IF_TYPE_AP:
 100                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
 101                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
 102                 break;
 103         case IEEE80211_IF_TYPE_MESH_POINT:
 104         case IEEE80211_IF_TYPE_STA:
 105         case IEEE80211_IF_TYPE_IBSS:
 106                 ifsta = &sdata->u.sta;
 107                 INIT_WORK(&ifsta->work, ieee80211_sta_work);
 108                 setup_timer(&ifsta->timer, ieee80211_sta_timer,
 109                             (unsigned long) sdata);
 110                 skb_queue_head_init(&ifsta->skb_queue);
 111
 112                 ifsta->capab = WLAN_CAPABILITY_ESS;
 113                 ifsta->auth_algs = IEEE80211_AUTH_ALG_OPEN |
 114                         IEEE80211_AUTH_ALG_SHARED_KEY;
 115                 ifsta->flags |= IEEE80211_STA_CREATE_IBSS |
 116                         IEEE80211_STA_AUTO_BSSID_SEL |
 117                         IEEE80211_STA_AUTO_CHANNEL_SEL;
 118                 if (ieee80211_num_regular_queues(&sdata->local->hw) >= 4)
 119                         ifsta->flags |= IEEE80211_STA_WMM_ENABLED;
 120
 121                 if (ieee80211_vif_is_mesh(&sdata->vif))
 122                         ieee80211_mesh_init_sdata(sdata);
 123                 break;
 124         case IEEE80211_IF_TYPE_MNTR:
 125                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 126                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
 127                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 128                                       MONITOR_FLAG_OTHER_BSS;
 129                 break;
 130         case IEEE80211_IF_TYPE_WDS:
 131         case IEEE80211_IF_TYPE_VLAN:
 132                 break;
 133         case IEEE80211_IF_TYPE_INVALID:
 134                 BUG();
 135                 break;
 136         }
 137
 138         ieee80211_debugfs_add_netdev(sdata);
 139 }
 140
 141 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 142                              enum ieee80211_if_types type)
 143 {
 144         ASSERT_RTNL();
 145
 146         if (type == sdata->vif.type)
 147                 return 0;
 148
 149         /*
 150          * We could, here, on changes between IBSS/STA/MESH modes,
 151          * invoke an MLME function instead that disassociates etc.
 152          * and goes into the requested mode.
 153          */
 154
 155         if (netif_running(sdata->dev))
 156                 return -EBUSY;
 157
 158         /* Purge and reset type-dependent state. */
 159         ieee80211_teardown_sdata(sdata->dev);
 160         ieee80211_setup_sdata(sdata, type);
 161
 162         /* reset some values that shouldn't be kept across type changes */
 163         sdata->basic_rates = 0;
 164         sdata->drop_unencrypted = 0;
 165
 166         return 0;
 167 }
 168
 169 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 170                      struct net_device **new_dev, enum ieee80211_if_types type,
 171                      struct vif_params *params)
 172 {
 173         struct net_device *ndev;
 174         struct ieee80211_sub_if_data *sdata = NULL;
 175         int ret, i;
 176
 177         ASSERT_RTNL();
 178
 179         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 180                             name, ieee80211_if_setup);
 181         if (!ndev)
 182                 return -ENOMEM;
 183
 184         ndev->needed_headroom = local->tx_headroom +
 185                                 4*6 /* four MAC addresses */
 186                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 187                                 + 6 /* mesh */
 188                                 + 8 /* rfc1042/bridge tunnel */
 189                                 - ETH_HLEN /* ethernet hard_header_len */
 190                                 + IEEE80211_ENCRYPT_HEADROOM;
 191         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 192
 193         ret = dev_alloc_name(ndev, ndev->name);
 194         if (ret < 0)
 195                 goto fail;
 196
 197         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 198         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 199
 200         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 201         sdata = netdev_priv(ndev);
 202         ndev->ieee80211_ptr = &sdata->wdev;
 203
 204         /* initialise type-independent data */
 205         sdata->wdev.wiphy = local->hw.wiphy;
 206         sdata->local = local;
 207         sdata->dev = ndev;
 208
 209         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 210                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 211
 212         INIT_LIST_HEAD(&sdata->key_list);
 213
 214         sdata->force_unicast_rateidx = -1;
 215         sdata->max_ratectrl_rateidx = -1;
 216
 217         /* setup type-dependent data */
 218         ieee80211_setup_sdata(sdata, type);
 219
 220         ret = register_netdevice(ndev);
 221         if (ret)
 222                 goto fail;
 223
 224         ndev->uninit = ieee80211_teardown_sdata;
 225
 226         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 227             params && params->mesh_id_len)
 228                 ieee80211_if_sta_set_mesh_id(&sdata->u.sta,
 229                                              params->mesh_id_len,
 230                                              params->mesh_id);
 231
 232         list_add_tail_rcu(&sdata->list, &local->interfaces);
 233
 234         if (new_dev)
 235                 *new_dev = ndev;
 236
 237         return 0;
 238
 239  fail:
 240         free_netdev(ndev);
 241         return ret;
 242 }
 243
 244 void ieee80211_if_remove(struct net_device *dev)
 245 {
 246         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 247
 248         ASSERT_RTNL();
 249
 250         list_del_rcu(&sdata->list);
 251         synchronize_rcu();
 252         unregister_netdevice(dev);
 253 }
 254
 255 /*
 256  * Remove all interfaces, may only be called at hardware unregistration
 257  * time because it doesn't do RCU-safe list removals.
 258  */
 259 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 260 {
 261         struct ieee80211_sub_if_data *sdata, *tmp;
 262
 263         ASSERT_RTNL();
 264
 265         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 266                 list_del(&sdata->list);
 267                 unregister_netdevice(sdata->dev);
 268         }
 269 }