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         /* free extra data */
  35         ieee80211_free_keys(sdata);
  36
  37         ieee80211_debugfs_remove_netdev(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                 if (ieee80211_vif_is_mesh(&sdata->vif))
  58                         mesh_rmc_free(sdata);
  59                 break;
  60         case IEEE80211_IF_TYPE_STA:
  61         case IEEE80211_IF_TYPE_IBSS:
  62                 kfree(sdata->u.sta.extra_ie);
  63                 kfree(sdata->u.sta.assocreq_ies);
  64                 kfree(sdata->u.sta.assocresp_ies);
  65                 kfree_skb(sdata->u.sta.probe_resp);
  66                 break;
  67         case IEEE80211_IF_TYPE_WDS:
  68         case IEEE80211_IF_TYPE_VLAN:
  69         case IEEE80211_IF_TYPE_MNTR:
  70                 break;
  71         case IEEE80211_IF_TYPE_INVALID:
  72                 BUG();
  73                 break;
  74         }
  75
  76         flushed = sta_info_flush(local, sdata);
  77         WARN_ON(flushed);
  78 }
  79
  80 /*
  81  * Helper function to initialise an interface to a specific type.
  82  */
  83 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
  84                                   enum ieee80211_if_types type)
  85 {
  86         /* clear type-dependent union */
  87         memset(&sdata->u, 0, sizeof(sdata->u));
  88
  89         /* and set some type-dependent values */
  90         sdata->vif.type = type;
  91
  92         /* only monitor differs */
  93         sdata->dev->type = ARPHRD_ETHER;
  94
  95         switch (type) {
  96         case IEEE80211_IF_TYPE_AP:
  97                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
  98                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
  99                 break;
 100         case IEEE80211_IF_TYPE_STA:
 101         case IEEE80211_IF_TYPE_IBSS:
 102                 ieee80211_sta_setup_sdata(sdata);
 103                 break;
 104         case IEEE80211_IF_TYPE_MESH_POINT:
 105                 if (ieee80211_vif_is_mesh(&sdata->vif))
 106                         ieee80211_mesh_init_sdata(sdata);
 107                 break;
 108         case IEEE80211_IF_TYPE_MNTR:
 109                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
 110                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
 111                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
 112                                       MONITOR_FLAG_OTHER_BSS;
 113                 break;
 114         case IEEE80211_IF_TYPE_WDS:
 115         case IEEE80211_IF_TYPE_VLAN:
 116                 break;
 117         case IEEE80211_IF_TYPE_INVALID:
 118                 BUG();
 119                 break;
 120         }
 121
 122         ieee80211_debugfs_add_netdev(sdata);
 123 }
 124
 125 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 126                              enum ieee80211_if_types type)
 127 {
 128         ASSERT_RTNL();
 129
 130         if (type == sdata->vif.type)
 131                 return 0;
 132
 133         /*
 134          * We could, here, on changes between IBSS/STA/MESH modes,
 135          * invoke an MLME function instead that disassociates etc.
 136          * and goes into the requested mode.
 137          */
 138
 139         if (netif_running(sdata->dev))
 140                 return -EBUSY;
 141
 142         /* Purge and reset type-dependent state. */
 143         ieee80211_teardown_sdata(sdata->dev);
 144         ieee80211_setup_sdata(sdata, type);
 145
 146         /* reset some values that shouldn't be kept across type changes */
 147         sdata->bss_conf.basic_rates =
 148                 ieee80211_mandatory_rates(sdata->local,
 149                         sdata->local->hw.conf.channel->band);
 150         sdata->drop_unencrypted = 0;
 151
 152         return 0;
 153 }
 154
 155 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 156                      struct net_device **new_dev, enum ieee80211_if_types type,
 157                      struct vif_params *params)
 158 {
 159         struct net_device *ndev;
 160         struct ieee80211_sub_if_data *sdata = NULL;
 161         int ret, i;
 162
 163         ASSERT_RTNL();
 164
 165         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
 166                             name, ieee80211_if_setup);
 167         if (!ndev)
 168                 return -ENOMEM;
 169
 170         ndev->needed_headroom = local->tx_headroom +
 171                                 4*6 /* four MAC addresses */
 172                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
 173                                 + 6 /* mesh */
 174                                 + 8 /* rfc1042/bridge tunnel */
 175                                 - ETH_HLEN /* ethernet hard_header_len */
 176                                 + IEEE80211_ENCRYPT_HEADROOM;
 177         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 178
 179         ret = dev_alloc_name(ndev, ndev->name);
 180         if (ret < 0)
 181                 goto fail;
 182
 183         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 184         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 185
 186         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
 187         sdata = netdev_priv(ndev);
 188         ndev->ieee80211_ptr = &sdata->wdev;
 189
 190         /* initialise type-independent data */
 191         sdata->wdev.wiphy = local->hw.wiphy;
 192         sdata->local = local;
 193         sdata->dev = ndev;
 194
 195         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 196                 skb_queue_head_init(&sdata->fragments[i].skb_list);
 197
 198         INIT_LIST_HEAD(&sdata->key_list);
 199
 200         sdata->force_unicast_rateidx = -1;
 201         sdata->max_ratectrl_rateidx = -1;
 202
 203         /* setup type-dependent data */
 204         ieee80211_setup_sdata(sdata, type);
 205
 206         ret = register_netdevice(ndev);
 207         if (ret)
 208                 goto fail;
 209
 210         ndev->uninit = ieee80211_teardown_sdata;
 211
 212         if (ieee80211_vif_is_mesh(&sdata->vif) &&
 213             params && params->mesh_id_len)
 214                 ieee80211_sdata_set_mesh_id(sdata,
 215                                             params->mesh_id_len,
 216                                             params->mesh_id);
 217
 218         list_add_tail_rcu(&sdata->list, &local->interfaces);
 219
 220         if (new_dev)
 221                 *new_dev = ndev;
 222
 223         return 0;
 224
 225  fail:
 226         free_netdev(ndev);
 227         return ret;
 228 }
 229
 230 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 231 {
 232         ASSERT_RTNL();
 233
 234         list_del_rcu(&sdata->list);
 235         synchronize_rcu();
 236         unregister_netdevice(sdata->dev);
 237 }
 238
 239 /*
 240  * Remove all interfaces, may only be called at hardware unregistration
 241  * time because it doesn't do RCU-safe list removals.
 242  */
 243 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 244 {
 245         struct ieee80211_sub_if_data *sdata, *tmp;
 246
 247         ASSERT_RTNL();
 248
 249         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
 250                 list_del(&sdata->list);
 251                 unregister_netdevice(sdata->dev);
 252         }
 253 }