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 /* fall through */ 169 case NL80211_IFTYPE_AP: 170 ra = skb->data; 171 break; 172 case NL80211_IFTYPE_WDS: 173 ra = sdata->u.wds.remote_addr; 174 break; 175 #ifdef CONFIG_MAC80211_MESH 176 case NL80211_IFTYPE_MESH_POINT: 177 qos = true; 178 break; 179 #endif 180 case NL80211_IFTYPE_STATION: 181 /* might be a TDLS station */ 182 sta = sta_info_get(sdata, skb->data); 183 if (sta) 184 qos = sta->sta.wme; 185 186 ra = sdata->u.mgd.bssid; 187 break; 188 case NL80211_IFTYPE_ADHOC: 189 ra = skb->data; 190 break; 191 case NL80211_IFTYPE_OCB: 192 /* all stations are required to support WME */ 193 qos = true; 194 break; 195 default: 196 break; 197 } 198 199 if (!sta && ra && !is_multicast_ether_addr(ra)) { 200 sta = sta_info_get(sdata, ra); 201 if (sta) 202 qos = sta->sta.wme; 203 } 204 205 if (!qos) { 206 skb->priority = 0; /* required for correct WPA/11i MIC */ 207 ret = IEEE80211_AC_BE; 208 goto out; 209 } 210 211 if (skb->protocol == sdata->control_port_protocol) { 212 skb->priority = 7; 213 goto downgrade; 214 } 215 216 /* use the data classifier to determine what 802.1d tag the 217 * data frame has */ 218 qos_map = rcu_dereference(sdata->qos_map); 219 skb->priority = cfg80211_classify8021d(skb, qos_map ? 220 &qos_map->qos_map : NULL); 221 222 downgrade: 223 ret = ieee80211_downgrade_queue(sdata, sta, skb); 224 out: 225 rcu_read_unlock(); 226 return ret; 227 } 228 229 /** 230 * ieee80211_set_qos_hdr - Fill in the QoS header if there is one. 231 * 232 * @sdata: local subif 233 * @skb: packet to be updated 234 */ 235 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata, 236 struct sk_buff *skb) 237 { 238 struct ieee80211_hdr *hdr = (void *)skb->data; 239 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 240 u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 241 u8 flags; 242 u8 *p; 243 244 if (!ieee80211_is_data_qos(hdr->frame_control)) 245 return; 246 247 p = ieee80211_get_qos_ctl(hdr); 248 249 /* set up the first byte */ 250 251 /* 252 * preserve everything but the TID and ACK policy 253 * (which we both write here) 254 */ 255 flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK | 256 IEEE80211_QOS_CTL_ACK_POLICY_MASK); 257 258 if (is_multicast_ether_addr(hdr->addr1) || 259 sdata->noack_map & BIT(tid)) { 260 flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK; 261 info->flags |= IEEE80211_TX_CTL_NO_ACK; 262 } 263 264 *p = flags | tid; 265 266 /* set up the second byte */ 267 p++; 268 269 if (ieee80211_vif_is_mesh(&sdata->vif)) { 270 /* preserve RSPI and Mesh PS Level bit */ 271 *p &= ((IEEE80211_QOS_CTL_RSPI | 272 IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8); 273 274 /* Nulls don't have a mesh header (frame body) */ 275 if (!ieee80211_is_qos_nullfunc(hdr->frame_control)) 276 *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8); 277 } else { 278 *p = 0; 279 } 280 } 281