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  * Copyright (C) 2022 Intel Corporation
   6  */
   7
   8 #include <linux/netdevice.h>
   9 #include <linux/skbuff.h>
  10 #include <linux/module.h>
  11 #include <linux/if_arp.h>
  12 #include <linux/types.h>
  13 #include <net/ip.h>
  14 #include <net/pkt_sched.h>
  15
  16 #include <net/mac80211.h>
  17 #include "ieee80211_i.h"
  18 #include "wme.h"
  19
  20 /* Default mapping in classifier to work with default
  21  * queue setup.
  22  */
  23 const int ieee802_1d_to_ac[8] = {
  24         IEEE80211_AC_BE,
  25         IEEE80211_AC_BK,
  26         IEEE80211_AC_BK,
  27         IEEE80211_AC_BE,
  28         IEEE80211_AC_VI,
  29         IEEE80211_AC_VI,
  30         IEEE80211_AC_VO,
  31         IEEE80211_AC_VO
  32 };
  33
  34 static int wme_downgrade_ac(struct sk_buff *skb)
  35 {
  36         switch (skb->priority) {
  37         case 6:
  38         case 7:
  39                 skb->priority = 5; /* VO -> VI */
  40                 return 0;
  41         case 4:
  42         case 5:
  43                 skb->priority = 3; /* VI -> BE */
  44                 return 0;
  45         case 0:
  46         case 3:
  47                 skb->priority = 2; /* BE -> BK */
  48                 return 0;
  49         default:
  50                 return -1;
  51         }
  52 }
  53
  54 /**
  55  * ieee80211_fix_reserved_tid - return the TID to use if this one is reserved
  56  * @tid: the assumed-reserved TID
  57  *
  58  * Returns: the alternative TID to use, or 0 on error
  59  */
  60 static inline u8 ieee80211_fix_reserved_tid(u8 tid)
  61 {
  62         switch (tid) {
  63         case 0:
  64                 return 3;
  65         case 1:
  66                 return 2;
  67         case 2:
  68                 return 1;
  69         case 3:
  70                 return 0;
  71         case 4:
  72                 return 5;
  73         case 5:
  74                 return 4;
  75         case 6:
  76                 return 7;
  77         case 7:
  78                 return 6;
  79         }
  80
  81         return 0;
  82 }
  83
  84 static u16 ieee80211_downgrade_queue(struct ieee80211_sub_if_data *sdata,
  85                                      struct sta_info *sta, struct sk_buff *skb)
  86 {
  87         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
  88
  89         /* in case we are a client verify acm is not set for this ac */
  90         while (sdata->wmm_acm & BIT(skb->priority)) {
  91                 int ac = ieee802_1d_to_ac[skb->priority];
  92
  93                 if (ifmgd->tx_tspec[ac].admitted_time &&
  94                     skb->priority == ifmgd->tx_tspec[ac].up)
  95                         return ac;
  96
  97                 if (wme_downgrade_ac(skb)) {
  98                         /*
  99                          * This should not really happen. The AP has marked all
 100                          * lower ACs to require admission control which is not
 101                          * a reasonable configuration. Allow the frame to be
 102                          * transmitted using AC_BK as a workaround.
 103                          */
 104                         break;
 105                 }
 106         }
 107
 108         /* Check to see if this is a reserved TID */
 109         if (sta && sta->reserved_tid == skb->priority)
 110                 skb->priority = ieee80211_fix_reserved_tid(skb->priority);
 111
 112         /* look up which queue to use for frames with this 1d tag */
 113         return ieee802_1d_to_ac[skb->priority];
 114 }
 115
 116 /* Indicate which queue to use for this fully formed 802.11 frame */
 117 u16 ieee80211_select_queue_80211(struct ieee80211_sub_if_data *sdata,
 118                                  struct sk_buff *skb,
 119                                  struct ieee80211_hdr *hdr)
 120 {
 121         struct ieee80211_local *local = sdata->local;
 122         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 123         u8 *p;
 124
 125         /* Ensure hash is set prior to potential SW encryption */
 126         skb_get_hash(skb);
 127
 128         if ((info->control.flags & IEEE80211_TX_CTRL_DONT_REORDER) ||
 129             local->hw.queues < IEEE80211_NUM_ACS)
 130                 return 0;
 131
 132         if (!ieee80211_is_data(hdr->frame_control)) {
 133                 skb->priority = 7;
 134                 return ieee802_1d_to_ac[skb->priority];
 135         }
 136         if (!ieee80211_is_data_qos(hdr->frame_control)) {
 137                 skb->priority = 0;
 138                 return ieee802_1d_to_ac[skb->priority];
 139         }
 140
 141         p = ieee80211_get_qos_ctl(hdr);
 142         skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
 143
 144         return ieee80211_downgrade_queue(sdata, NULL, skb);
 145 }
 146
 147 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
 148                            struct sta_info *sta, struct sk_buff *skb)
 149 {
 150         const struct ethhdr *eth = (void *)skb->data;
 151         struct mac80211_qos_map *qos_map;
 152         bool qos;
 153
 154         /* Ensure hash is set prior to potential SW encryption */
 155         skb_get_hash(skb);
 156
 157         /* all mesh/ocb stations are required to support WME */
 158         if ((sdata->vif.type == NL80211_IFTYPE_MESH_POINT &&
 159             !is_multicast_ether_addr(eth->h_dest)) ||
 160             (sdata->vif.type == NL80211_IFTYPE_OCB && sta))
 161                 qos = true;
 162         else if (sta)
 163                 qos = sta->sta.wme;
 164         else
 165                 qos = false;
 166
 167         if (!qos) {
 168                 skb->priority = 0; /* required for correct WPA/11i MIC */
 169                 return IEEE80211_AC_BE;
 170         }
 171
 172         if (skb->protocol == sdata->control_port_protocol) {
 173                 skb->priority = 7;
 174                 goto downgrade;
 175         }
 176
 177         /* use the data classifier to determine what 802.1d tag the
 178          * data frame has */
 179         qos_map = rcu_dereference(sdata->qos_map);
 180         skb->priority = cfg80211_classify8021d(skb, qos_map ?
 181                                                &qos_map->qos_map : NULL);
 182
 183  downgrade:
 184         return ieee80211_downgrade_queue(sdata, sta, skb);
 185 }
 186
 187 /**
 188  * ieee80211_set_qos_hdr - Fill in the QoS header if there is one.
 189  *
 190  * @sdata: local subif
 191  * @skb: packet to be updated
 192  */
 193 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
 194                            struct sk_buff *skb)
 195 {
 196         struct ieee80211_hdr *hdr = (void *)skb->data;
 197         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 198         u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
 199         u8 flags;
 200         u8 *p;
 201
 202         if (!ieee80211_is_data_qos(hdr->frame_control))
 203                 return;
 204
 205         p = ieee80211_get_qos_ctl(hdr);
 206
 207         /* don't overwrite the QoS field of injected frames */
 208         if (info->flags & IEEE80211_TX_CTL_INJECTED) {
 209                 /* do take into account Ack policy of injected frames */
 210                 if (*p & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
 211                         info->flags |= IEEE80211_TX_CTL_NO_ACK;
 212                 return;
 213         }
 214
 215         /* set up the first byte */
 216
 217         /*
 218          * preserve everything but the TID and ACK policy
 219          * (which we both write here)
 220          */
 221         flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK |
 222                        IEEE80211_QOS_CTL_ACK_POLICY_MASK);
 223
 224         if (is_multicast_ether_addr(hdr->addr1) ||
 225             sdata->noack_map & BIT(tid)) {
 226                 flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
 227                 info->flags |= IEEE80211_TX_CTL_NO_ACK;
 228         }
 229
 230         *p = flags | tid;
 231
 232         /* set up the second byte */
 233         p++;
 234
 235         if (ieee80211_vif_is_mesh(&sdata->vif)) {
 236                 /* preserve RSPI and Mesh PS Level bit */
 237                 *p &= ((IEEE80211_QOS_CTL_RSPI |
 238                         IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8);
 239
 240                 /* Nulls don't have a mesh header (frame body) */
 241                 if (!ieee80211_is_qos_nullfunc(hdr->frame_control))
 242                         *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
 243         } else {
 244                 *p = 0;
 245         }
 246 }