xref: /kernel/linux/linux-5.10/net/mac80211/wme.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2004, Instant802 Networks, Inc.
4 * Copyright 2013-2014  Intel Mobile Communications GmbH
5 */
6
7#include <linux/netdevice.h>
8#include <linux/skbuff.h>
9#include <linux/module.h>
10#include <linux/if_arp.h>
11#include <linux/types.h>
12#include <net/ip.h>
13#include <net/pkt_sched.h>
14
15#include <net/mac80211.h>
16#include "ieee80211_i.h"
17#include "wme.h"
18
19/* Default mapping in classifier to work with default
20 * queue setup.
21 */
22const int ieee802_1d_to_ac[8] = {
23	IEEE80211_AC_BE,
24	IEEE80211_AC_BK,
25	IEEE80211_AC_BK,
26	IEEE80211_AC_BE,
27	IEEE80211_AC_VI,
28	IEEE80211_AC_VI,
29	IEEE80211_AC_VO,
30	IEEE80211_AC_VO
31};
32
33static int wme_downgrade_ac(struct sk_buff *skb)
34{
35	switch (skb->priority) {
36	case 6:
37	case 7:
38		skb->priority = 5; /* VO -> VI */
39		return 0;
40	case 4:
41	case 5:
42		skb->priority = 3; /* VI -> BE */
43		return 0;
44	case 0:
45	case 3:
46		skb->priority = 2; /* BE -> BK */
47		return 0;
48	default:
49		return -1;
50	}
51}
52
53/**
54 * ieee80211_fix_reserved_tid - return the TID to use if this one is reserved
55 * @tid: the assumed-reserved TID
56 *
57 * Returns: the alternative TID to use, or 0 on error
58 */
59static inline u8 ieee80211_fix_reserved_tid(u8 tid)
60{
61	switch (tid) {
62	case 0:
63		return 3;
64	case 1:
65		return 2;
66	case 2:
67		return 1;
68	case 3:
69		return 0;
70	case 4:
71		return 5;
72	case 5:
73		return 4;
74	case 6:
75		return 7;
76	case 7:
77		return 6;
78	}
79
80	return 0;
81}
82
83static u16 ieee80211_downgrade_queue(struct ieee80211_sub_if_data *sdata,
84				     struct sta_info *sta, struct sk_buff *skb)
85{
86	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
87
88	/* in case we are a client verify acm is not set for this ac */
89	while (sdata->wmm_acm & BIT(skb->priority)) {
90		int ac = ieee802_1d_to_ac[skb->priority];
91
92		if (ifmgd->tx_tspec[ac].admitted_time &&
93		    skb->priority == ifmgd->tx_tspec[ac].up)
94			return ac;
95
96		if (wme_downgrade_ac(skb)) {
97			/*
98			 * This should not really happen. The AP has marked all
99			 * lower ACs to require admission control which is not
100			 * a reasonable configuration. Allow the frame to be
101			 * transmitted using AC_BK as a workaround.
102			 */
103			break;
104		}
105	}
106
107	/* Check to see if this is a reserved TID */
108	if (sta && sta->reserved_tid == skb->priority)
109		skb->priority = ieee80211_fix_reserved_tid(skb->priority);
110
111	/* look up which queue to use for frames with this 1d tag */
112	return ieee802_1d_to_ac[skb->priority];
113}
114
115/* Indicate which queue to use for this fully formed 802.11 frame */
116u16 ieee80211_select_queue_80211(struct ieee80211_sub_if_data *sdata,
117				 struct sk_buff *skb,
118				 struct ieee80211_hdr *hdr)
119{
120	struct ieee80211_local *local = sdata->local;
121	u8 *p;
122
123	if (local->hw.queues < IEEE80211_NUM_ACS)
124		return 0;
125
126	if (!ieee80211_is_data(hdr->frame_control)) {
127		skb->priority = 7;
128		return ieee802_1d_to_ac[skb->priority];
129	}
130	if (!ieee80211_is_data_qos(hdr->frame_control)) {
131		skb->priority = 0;
132		return ieee802_1d_to_ac[skb->priority];
133	}
134
135	p = ieee80211_get_qos_ctl(hdr);
136	skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
137
138	return ieee80211_downgrade_queue(sdata, NULL, skb);
139}
140
141u16 __ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
142			     struct sta_info *sta, struct sk_buff *skb)
143{
144	const struct ethhdr *eth = (void *)skb->data;
145	struct mac80211_qos_map *qos_map;
146	bool qos;
147
148	/* all mesh/ocb stations are required to support WME */
149	if ((sdata->vif.type == NL80211_IFTYPE_MESH_POINT &&
150	    !is_multicast_ether_addr(eth->h_dest)) ||
151	    (sdata->vif.type == NL80211_IFTYPE_OCB && sta))
152		qos = true;
153	else if (sta)
154		qos = sta->sta.wme;
155	else
156		qos = false;
157
158	if (!qos) {
159		skb->priority = 0; /* required for correct WPA/11i MIC */
160		return IEEE80211_AC_BE;
161	}
162
163	if (skb->protocol == sdata->control_port_protocol) {
164		skb->priority = 7;
165		goto downgrade;
166	}
167
168	/* use the data classifier to determine what 802.1d tag the
169	 * data frame has */
170	qos_map = rcu_dereference(sdata->qos_map);
171	skb->priority = cfg80211_classify8021d(skb, qos_map ?
172					       &qos_map->qos_map : NULL);
173
174 downgrade:
175	return ieee80211_downgrade_queue(sdata, sta, skb);
176}
177
178
179/* Indicate which queue to use. */
180u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
181			   struct sk_buff *skb)
182{
183	struct ieee80211_local *local = sdata->local;
184	struct sta_info *sta = NULL;
185	const u8 *ra = NULL;
186	u16 ret;
187
188	/* when using iTXQ, we can do this later */
189	if (local->ops->wake_tx_queue)
190		return 0;
191
192	if (local->hw.queues < IEEE80211_NUM_ACS || skb->len < 6) {
193		skb->priority = 0; /* required for correct WPA/11i MIC */
194		return 0;
195	}
196
197	rcu_read_lock();
198	switch (sdata->vif.type) {
199	case NL80211_IFTYPE_AP_VLAN:
200		sta = rcu_dereference(sdata->u.vlan.sta);
201		if (sta)
202			break;
203		fallthrough;
204	case NL80211_IFTYPE_AP:
205		ra = skb->data;
206		break;
207	case NL80211_IFTYPE_WDS:
208		ra = sdata->u.wds.remote_addr;
209		break;
210	case NL80211_IFTYPE_STATION:
211		/* might be a TDLS station */
212		sta = sta_info_get(sdata, skb->data);
213		if (sta)
214			break;
215
216		ra = sdata->u.mgd.bssid;
217		break;
218	case NL80211_IFTYPE_ADHOC:
219		ra = skb->data;
220		break;
221	default:
222		break;
223	}
224
225	if (!sta && ra && !is_multicast_ether_addr(ra))
226		sta = sta_info_get(sdata, ra);
227
228	ret = __ieee80211_select_queue(sdata, sta, skb);
229
230	rcu_read_unlock();
231	return ret;
232}
233
234/**
235 * ieee80211_set_qos_hdr - Fill in the QoS header if there is one.
236 *
237 * @sdata: local subif
238 * @skb: packet to be updated
239 */
240void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
241			   struct sk_buff *skb)
242{
243	struct ieee80211_hdr *hdr = (void *)skb->data;
244	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
245	u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
246	u8 flags;
247	u8 *p;
248
249	if (!ieee80211_is_data_qos(hdr->frame_control))
250		return;
251
252	p = ieee80211_get_qos_ctl(hdr);
253
254	/* set up the first byte */
255
256	/*
257	 * preserve everything but the TID and ACK policy
258	 * (which we both write here)
259	 */
260	flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK |
261		       IEEE80211_QOS_CTL_ACK_POLICY_MASK);
262
263	if (is_multicast_ether_addr(hdr->addr1) ||
264	    sdata->noack_map & BIT(tid)) {
265		flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
266		info->flags |= IEEE80211_TX_CTL_NO_ACK;
267	}
268
269	*p = flags | tid;
270
271	/* set up the second byte */
272	p++;
273
274	if (ieee80211_vif_is_mesh(&sdata->vif)) {
275		/* preserve RSPI and Mesh PS Level bit */
276		*p &= ((IEEE80211_QOS_CTL_RSPI |
277			IEEE80211_QOS_CTL_MESH_PS_LEVEL) >> 8);
278
279		/* Nulls don't have a mesh header (frame body) */
280		if (!ieee80211_is_qos_nullfunc(hdr->frame_control))
281			*p |= (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8);
282	} else {
283		*p = 0;
284	}
285}
286