1 /* 2 * Copyright 2004, Instant802 Networks, Inc. 3 * Copyright 2013-2014 Intel Mobile Communications GmbH 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/netdevice.h> 11 #include <linux/skbuff.h> 12 #include <linux/module.h> 13 #include <linux/if_arp.h> 14 #include <linux/types.h> 15 #include <net/ip.h> 16 #include <net/pkt_sched.h> 17 18 #include <net/mac80211.h> 19 #include "ieee80211_i.h" 20 #include "wme.h" 21 22 /* Default mapping in classifier to work with default 23 * queue setup. 24 */ 25 const int ieee802_1d_to_ac[8] = { 26 IEEE80211_AC_BE, 27 IEEE80211_AC_BK, 28 IEEE80211_AC_BK, 29 IEEE80211_AC_BE, 30 IEEE80211_AC_VI, 31 IEEE80211_AC_VI, 32 IEEE80211_AC_VO, 33 IEEE80211_AC_VO 34 }; 35 36 static int wme_downgrade_ac(struct sk_buff *skb) 37 { 38 switch (skb->priority) { 39 case 6: 40 case 7: 41 skb->priority = 5; /* VO -> VI */ 42 return 0; 43 case 4: 44 case 5: 45 skb->priority = 3; /* VI -> BE */ 46 return 0; 47 case 0: 48 case 3: 49 skb->priority = 2; /* BE -> BK */ 50 return 0; 51 default: 52 return -1; 53 } 54 } 55 56 /** 57 * ieee80211_fix_reserved_tid - return the TID to use if this one is reserved 58 * @tid: the assumed-reserved TID 59 * 60 * Returns: the alternative TID to use, or 0 on error 61 */ 62 static inline u8 ieee80211_fix_reserved_tid(u8 tid) 63 { 64 switch (tid) { 65 case 0: 66 return 3; 67 case 1: 68 return 2; 69 case 2: 70 return 1; 71 case 3: 72 return 0; 73 case 4: 74 return 5; 75 case 5: 76 return 4; 77 case 6: 78 return 7; 79 case 7: 80 return 6; 81 } 82 83 return 0; 84 } 85 86 static u16 ieee80211_downgrade_queue(struct ieee80211_sub_if_data *sdata, 87 struct sta_info *sta, struct sk_buff *skb) 88 { 89 struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; 90 91 /* in case we are a client verify acm is not set for this ac */ 92 while (sdata->wmm_acm & BIT(skb->priority)) { 93 int ac = ieee802_1d_to_ac[skb->priority]; 94 95 if (ifmgd->tx_tspec[ac].admitted_time && 96 skb->priority == ifmgd->tx_tspec[ac].up) 97 return ac; 98 99 if (wme_downgrade_ac(skb)) { 100 /* 101 * This should not really happen. The AP has marked all 102 * lower ACs to require admission control which is not 103 * a reasonable configuration. Allow the frame to be 104 * transmitted using AC_BK as a workaround. 105 */ 106 break; 107 } 108 } 109 110 /* Check to see if this is a reserved TID */ 111 if (sta && sta->reserved_tid == skb->priority) 112 skb->priority = ieee80211_fix_reserved_tid(skb->priority); 113 114 /* look up which queue to use for frames with this 1d tag */ 115 return ieee802_1d_to_ac[skb->priority]; 116 } 117 118 /* Indicate which queue to use for this fully formed 802.11 frame */ 119 u16 ieee80211_select_queue_80211(struct ieee80211_sub_if_data *sdata, 120 struct sk_buff *skb, 121 struct ieee80211_hdr *hdr) 122 { 123 struct ieee80211_local *local = sdata->local; 124 u8 *p; 125 126 if (local->hw.queues < IEEE80211_NUM_ACS) 127 return 0; 128 129 if (!ieee80211_is_data(hdr->frame_control)) { 130 skb->priority = 7; 131 return ieee802_1d_to_ac[skb->priority]; 132 } 133 if (!ieee80211_is_data_qos(hdr->frame_control)) { 134 skb->priority = 0; 135 return ieee802_1d_to_ac[skb->priority]; 136 } 137 138 p = ieee80211_get_qos_ctl(hdr); 139 skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK; 140 141 return ieee80211_downgrade_queue(sdata, NULL, skb); 142 } 143 144 /* Indicate which queue to use. */ 145 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata, 146 struct sk_buff *skb) 147 { 148 struct ieee80211_local *local = sdata->local; 149 struct sta_info *sta = NULL; 150 const u8 *ra = NULL; 151 bool qos = false; 152 struct mac80211_qos_map *qos_map; 153 u16 ret; 154 155 if (local->hw.queues < IEEE80211_NUM_ACS || skb->len < 6) { 156 skb->priority = 0; /* required for correct WPA/11i MIC */ 157 return 0; 158 } 159 160 rcu_read_lock(); 161 switch (sdata->vif.type) { 162 case NL80211_IFTYPE_AP_VLAN: 163 sta = rcu_dereference(sdata->u.vlan.sta); 164 if (sta) { 165 qos = sta->sta.wme; 166 break; 167 } 168 case NL80211_IFTYPE_AP: 169 ra = skb->data; 170 break; 171 case NL80211_IFTYPE_WDS: 172 ra = sdata->u.wds.remote_addr; 173 break; 174 #ifdef CONFIG_MAC80211_MESH 175 case NL80211_IFTYPE_MESH_POINT: 176 qos = true; 177 break; 178 #endif 179 case NL80211_IFTYPE_STATION: 180 /* might be a TDLS station */ 181 sta = sta_info_get(sdata, skb->data); 182 if (sta) 183 qos = sta->sta.wme; 184 185 ra = sdata->u.mgd.bssid; 186 break; 187 case NL80211_IFTYPE_ADHOC: 188 ra = skb->data; 189 break; 190 case NL80211_IFTYPE_OCB: 191 /* all stations are required to support WME */ 192 qos = true; 193 break; 194 default: 195 break; 196 } 197 198 if (!sta && ra && !is_multicast_ether_addr(ra)) { 199 sta = sta_info_get(sdata, ra); 200 if (sta) 201 qos = sta->sta.wme; 202 } 203 204 if (!qos) { 205 skb->priority = 0; /* required for correct WPA/11i MIC */ 206 ret = IEEE80211_AC_BE; 207 goto out; 208 } 209 210 if (skb->protocol == sdata->control_port_protocol) { 211 skb->priority = 7; 212 goto downgrade; 213 } 214 215 /* use the data classifier to determine what 802.1d tag the 216 * data frame has */ 217 qos_map = rcu_dereference(sdata->qos_map); 218 skb->priority = cfg80211_classify8021d(skb, qos_map ? 219 &qos_map->qos_map : NULL); 220 221 downgrade: 222 ret = ieee80211_downgrade_queue(sdata, sta, skb); 223 out: 224 rcu_read_unlock(); 225 return ret; 226 } 227 228 /** 229 * ieee80211_set_qos_hdr - Fill in the QoS header if there is one. 230 * 231 * @sdata: local subif 232 * @skb: packet to be updated 233 */ 234 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata, 235 struct sk_buff *skb) 236 { 237 struct ieee80211_hdr *hdr = (void *)skb->data; 238 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 239 u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 240 u8 flags; 241 u8 *p; 242 243 if (!ieee80211_is_data_qos(hdr->frame_control)) 244 return; 245 246 p = ieee80211_get_qos_ctl(hdr); 247 248 /* set up the first byte */ 249 250 /* 251 * preserve everything but the TID and ACK policy 252 * (which we both write here) 253 */ 254 flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK | 255 IEEE80211_QOS_CTL_ACK_POLICY_MASK); 256 257 if (is_multicast_ether_addr(hdr->addr1) || 258 sdata->noack_map & BIT(tid)) { 259 flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK; 260 info->flags |= IEEE80211_TX_CTL_NO_ACK; 261 } 262 263 *p = flags | tid; 264 265 /* set up the second byte */ 266 p++; 267 268 if (ieee80211_vif_is_mesh(&sdata->vif)) { 269 /* preserve RSPI and Mesh PS Level bit */ 270 *p &= ((IEEE80211_QOS_CTL_RSPI | 271 IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8); 272 273 /* Nulls don't have a mesh header (frame body) */ 274 if (!ieee80211_is_qos_nullfunc(hdr->frame_control)) 275 *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8); 276 } else { 277 *p = 0; 278 } 279 } 280