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
wme_downgrade_ac(struct sk_buff * skb)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 */
ieee80211_fix_reserved_tid(u8 tid)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
ieee80211_downgrade_queue(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct sk_buff * skb)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 */
ieee80211_select_queue_80211(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb,struct ieee80211_hdr * hdr)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. */
ieee80211_select_queue(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)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 */
ieee80211_set_qos_hdr(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)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 *p;
240 u8 ack_policy, tid;
241
242 if (!ieee80211_is_data_qos(hdr->frame_control))
243 return;
244
245 p = ieee80211_get_qos_ctl(hdr);
246 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
247
248 /* preserve EOSP bit */
249 ack_policy = *p & IEEE80211_QOS_CTL_EOSP;
250
251 if (is_multicast_ether_addr(hdr->addr1) ||
252 sdata->noack_map & BIT(tid)) {
253 ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
254 info->flags |= IEEE80211_TX_CTL_NO_ACK;
255 }
256
257 /* qos header is 2 bytes */
258 *p++ = ack_policy | tid;
259 if (ieee80211_vif_is_mesh(&sdata->vif)) {
260 /* preserve RSPI and Mesh PS Level bit */
261 *p &= ((IEEE80211_QOS_CTL_RSPI |
262 IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8);
263
264 /* Nulls don't have a mesh header (frame body) */
265 if (!ieee80211_is_qos_nullfunc(hdr->frame_control))
266 *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
267 } else {
268 *p = 0;
269 }
270 }
271