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 */
23const 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
34static 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 */
60static 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
84static 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(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 */
117u16 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(fc: hdr->frame_control)) {
133 skb->priority = 7;
134 return ieee802_1d_to_ac[skb->priority];
135 }
136 if (!ieee80211_is_data_qos(fc: 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
147u16 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(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: 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 */
193void 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(fc: 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(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(vif: &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(fc: hdr->frame_control))
242 *p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
243 } else {
244 *p = 0;
245 }
246}
247

source code of linux/net/mac80211/wme.c