net/mac80211/wme.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2004, Instant802 Networks, Inc.
   4  * Copyright 2013-2014  Intel Mobile Communications GmbH
   5  */
   6
   7 #include <linux/netdevice.h>
   8 #include <linux/skbuff.h>
   9 #include <linux/module.h>
  10 #include <linux/if_arp.h>
  11 #include <linux/types.h>
  12 #include <net/ip.h>
  13 #include <net/pkt_sched.h>
  14
  15 #include <net/mac80211.h>
  16 #include "ieee80211_i.h"
  17 #include "wme.h"
  18
  19 /* Default mapping in classifier to work with default
  20  * queue setup.
  21  */
  22 const int ieee802_1d_to_ac[8] = {
  23         IEEE80211_AC_BE,
  24         IEEE80211_AC_BK,
  25         IEEE80211_AC_BK,
  26         IEEE80211_AC_BE,
  27         IEEE80211_AC_VI,
  28         IEEE80211_AC_VI,
  29         IEEE80211_AC_VO,
  30         IEEE80211_AC_VO
  31 };
  32
  33 static int wme_downgrade_ac(struct sk_buff *skb)
  34 {
  35         switch (skb->priority) {
  36         case 6:
  37         case 7:
  38                 skb->priority = 5; /* VO -> VI */
  39                 return 0;
  40         case 4:
  41         case 5:
  42                 skb->priority = 3; /* VI -> BE */
  43                 return 0;
  44         case 0:
  45         case 3:
  46                 skb->priority = 2; /* BE -> BK */
  47                 return 0;
  48         default:
  49                 return -1;
  50         }
  51 }
  52
  53 /**
  54  * ieee80211_fix_reserved_tid - return the TID to use if this one is reserved
  55  * @tid: the assumed-reserved TID
  56  *
  57  * Returns: the alternative TID to use, or 0 on error
  58  */
  59 static inline u8 ieee80211_fix_reserved_tid(u8 tid)
  60 {
  61         switch (tid) {
  62         case 0:
  63                 return 3;
  64         case 1:
  65                 return 2;
  66         case 2:
  67                 return 1;
  68         case 3:
  69                 return 0;
  70         case 4:
  71                 return 5;
  72         case 5:
  73                 return 4;
  74         case 6:
  75                 return 7;
  76         case 7:
  77                 return 6;
  78         }
  79
  80         return 0;
  81 }
  82
  83 static u16 ieee80211_downgrade_queue(struct ieee80211_sub_if_data *sdata,
  84                                      struct sta_info *sta, struct sk_buff *skb)
  85 {
  86         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
  87
  88         /* in case we are a client verify acm is not set for this ac */
  89         while (sdata->wmm_acm & BIT(skb->priority)) {
  90                 int ac = ieee802_1d_to_ac[skb->priority];
  91
  92                 if (ifmgd->tx_tspec[ac].admitted_time &&
  93                     skb->priority == ifmgd->tx_tspec[ac].up)
  94                         return ac;
  95
  96                 if (wme_downgrade_ac(skb)) {
  97                         /*
  98                          * This should not really happen. The AP has marked all
  99                          * lower ACs to require admission control which is not
 100                          * a reasonable configuration. Allow the frame to be
 101                          * transmitted using AC_BK as a workaround.
 102                          */
 103                         break;
 104                 }
 105         }
 106
 107         /* Check to see if this is a reserved TID */
 108         if (sta && sta->reserved_tid == skb->priority)
 109                 skb->priority = ieee80211_fix_reserved_tid(skb->priority);
 110
 111         /* look up which queue to use for frames with this 1d tag */
 112         return ieee802_1d_to_ac[skb->priority];
 113 }
 114
 115 /* Indicate which queue to use for this fully formed 802.11 frame */
 116 u16 ieee80211_select_queue_80211(struct ieee80211_sub_if_data *sdata,
 117                                  struct sk_buff *skb,
 118                                  struct ieee80211_hdr *hdr)
 119 {
 120         struct ieee80211_local *local = sdata->local;
 121         u8 *p;
 122
 123         if (local->hw.queues < IEEE80211_NUM_ACS)
 124                 return 0;
 125
 126         if (!ieee80211_is_data(hdr->frame_control)) {
 127                 skb->priority = 7;
 128                 return ieee802_1d_to_ac[skb->priority];
 129         }
 130         if (!ieee80211_is_data_qos(hdr->frame_control)) {
 131                 skb->priority = 0;
 132                 return ieee802_1d_to_ac[skb->priority];
 133         }
 134
 135         p = ieee80211_get_qos_ctl(hdr);
 136         skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
 137
 138         return ieee80211_downgrade_queue(sdata, NULL, skb);
 139 }
 140
 141 u16 __ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
 142                              struct sta_info *sta, struct sk_buff *skb)
 143 {
 144         struct mac80211_qos_map *qos_map;
 145         bool qos;
 146
 147         /* all mesh/ocb stations are required to support WME */
 148         if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
 149             sdata->vif.type == NL80211_IFTYPE_OCB)
 150                 qos = true;
 151         else if (sta)
 152                 qos = sta->sta.wme;
 153         else
 154                 qos = false;
 155
 156         if (!qos) {
 157                 skb->priority = 0; /* required for correct WPA/11i MIC */
 158                 return IEEE80211_AC_BE;
 159         }
 160
 161         if (skb->protocol == sdata->control_port_protocol) {
 162                 skb->priority = 7;
 163                 goto downgrade;
 164         }
 165
 166         /* use the data classifier to determine what 802.1d tag the
 167          * data frame has */
 168         qos_map = rcu_dereference(sdata->qos_map);
 169         skb->priority = cfg80211_classify8021d(skb, qos_map ?
 170                                                &qos_map->qos_map : NULL);
 171
 172  downgrade:
 173         return ieee80211_downgrade_queue(sdata, sta, skb);
 174 }
 175
 176
 177 /* Indicate which queue to use. */
 178 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
 179                            struct sk_buff *skb)
 180 {
 181         struct ieee80211_local *local = sdata->local;
 182         struct sta_info *sta = NULL;
 183         const u8 *ra = NULL;
 184         u16 ret;
 185
 186         /* when using iTXQ, we can do this later */
 187         if (local->ops->wake_tx_queue)
 188                 return 0;
 189
 190         if (local->hw.queues < IEEE80211_NUM_ACS || skb->len < 6) {
 191                 skb->priority = 0; /* required for correct WPA/11i MIC */
 192                 return 0;
 193         }
 194
 195         rcu_read_lock();
 196         switch (sdata->vif.type) {
 197         case NL80211_IFTYPE_AP_VLAN:
 198                 sta = rcu_dereference(sdata->u.vlan.sta);
 199                 if (sta)
 200                         break;
 201                 /* fall through */
 202         case NL80211_IFTYPE_AP:
 203                 ra = skb->data;
 204                 break;
 205         case NL80211_IFTYPE_WDS:
 206                 ra = sdata->u.wds.remote_addr;
 207                 break;
 208         case NL80211_IFTYPE_STATION:
 209                 /* might be a TDLS station */
 210                 sta = sta_info_get(sdata, skb->data);
 211                 if (sta)
 212                         break;
 213
 214                 ra = sdata->u.mgd.bssid;
 215                 break;
 216         case NL80211_IFTYPE_ADHOC:
 217                 ra = skb->data;
 218                 break;
 219         default:
 220                 break;
 221         }
 222
 223         if (!sta && ra && !is_multicast_ether_addr(ra))
 224                 sta = sta_info_get(sdata, ra);
 225
 226         ret = __ieee80211_select_queue(sdata, sta, skb);
 227
 228         rcu_read_unlock();
 229         return ret;
 230 }
 231
 232 /**
 233  * ieee80211_set_qos_hdr - Fill in the QoS header if there is one.
 234  *
 235  * @sdata: local subif
 236  * @skb: packet to be updated
 237  */
 238 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
 239                            struct sk_buff *skb)
 240 {
 241         struct ieee80211_hdr *hdr = (void *)skb->data;
 242         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 243         u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
 244         u8 flags;
 245         u8 *p;
 246
 247         if (!ieee80211_is_data_qos(hdr->frame_control))
 248                 return;
 249
 250         p = ieee80211_get_qos_ctl(hdr);
 251
 252         /* set up the first byte */
 253
 254         /*
 255          * preserve everything but the TID and ACK policy
 256          * (which we both write here)
 257          */
 258         flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK |
 259                        IEEE80211_QOS_CTL_ACK_POLICY_MASK);
 260
 261         if (is_multicast_ether_addr(hdr->addr1) ||
 262             sdata->noack_map & BIT(tid)) {
 263                 flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
 264                 info->flags |= IEEE80211_TX_CTL_NO_ACK;
 265         }
 266
 267         *p = flags | tid;
 268
 269         /* set up the second byte */
 270         p++;
 271
 272         if (ieee80211_vif_is_mesh(&sdata->vif)) {
 273                 /* preserve RSPI and Mesh PS Level bit */
 274                 *p &= ((IEEE80211_QOS_CTL_RSPI |
 275                         IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8);
 276
 277                 /* Nulls don't have a mesh header (frame body) */
 278                 if (!ieee80211_is_qos_nullfunc(hdr->frame_control))
 279                         *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
 280         } else {
 281                 *p = 0;
 282         }
 283 }