1 /*
2 * hostapd / WMM (Wi-Fi Multimedia)
3 * Copyright 2002-2003, Instant802 Networks, Inc.
4 * Copyright 2005-2006, Devicescape Software, Inc.
5 * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
6 *
7 * This software may be distributed under the terms of the BSD license.
8 * See README for more details.
9 */
10
11 #include "utils/includes.h"
12
13 #include "utils/common.h"
14 #include "common/ieee802_11_defs.h"
15 #include "common/ieee802_11_common.h"
16 #include "hostapd.h"
17 #include "ieee802_11.h"
18 #include "sta_info.h"
19 #include "ap_config.h"
20 #include "ap_drv_ops.h"
21 #include "wmm.h"
22
23
wmm_aci_aifsn(int aifsn,int acm,int aci)24 static inline u8 wmm_aci_aifsn(int aifsn, int acm, int aci)
25 {
26 u8 ret;
27 ret = (aifsn << WMM_AC_AIFNS_SHIFT) & WMM_AC_AIFSN_MASK;
28 if (acm)
29 ret |= WMM_AC_ACM;
30 ret |= (aci << WMM_AC_ACI_SHIFT) & WMM_AC_ACI_MASK;
31 return ret;
32 }
33
34
wmm_ecw(int ecwmin,int ecwmax)35 static inline u8 wmm_ecw(int ecwmin, int ecwmax)
36 {
37 return ((ecwmin << WMM_AC_ECWMIN_SHIFT) & WMM_AC_ECWMIN_MASK) |
38 ((ecwmax << WMM_AC_ECWMAX_SHIFT) & WMM_AC_ECWMAX_MASK);
39 }
40
41
42 /*
43 * Add WMM Parameter Element to Beacon, Probe Response, and (Re)Association
44 * Response frames.
45 */
hostapd_eid_wmm(struct hostapd_data * hapd,u8 * eid)46 u8 * hostapd_eid_wmm(struct hostapd_data *hapd, u8 *eid)
47 {
48 u8 *pos = eid;
49 struct wmm_parameter_element *wmm =
50 (struct wmm_parameter_element *) (pos + 2);
51 int e;
52
53 if (!hapd->conf->wmm_enabled)
54 return eid;
55 eid[0] = WLAN_EID_VENDOR_SPECIFIC;
56 wmm->oui[0] = 0x00;
57 wmm->oui[1] = 0x50;
58 wmm->oui[2] = 0xf2;
59 wmm->oui_type = WMM_OUI_TYPE;
60 wmm->oui_subtype = WMM_OUI_SUBTYPE_PARAMETER_ELEMENT;
61 wmm->version = WMM_VERSION;
62 wmm->qos_info = hapd->parameter_set_count & 0xf;
63
64 if (hapd->conf->wmm_uapsd &&
65 (hapd->iface->drv_flags & WPA_DRIVER_FLAGS_AP_UAPSD))
66 wmm->qos_info |= 0x80;
67
68 wmm->reserved = 0;
69
70 /* fill in a parameter set record for each AC */
71 for (e = 0; e < 4; e++) {
72 struct wmm_ac_parameter *ac = &wmm->ac[e];
73 struct hostapd_wmm_ac_params *acp =
74 &hapd->iconf->wmm_ac_params[e];
75
76 ac->aci_aifsn = wmm_aci_aifsn(acp->aifs,
77 acp->admission_control_mandatory,
78 e);
79 ac->cw = wmm_ecw(acp->cwmin, acp->cwmax);
80 ac->txop_limit = host_to_le16(acp->txop_limit);
81 }
82
83 pos = (u8 *) (wmm + 1);
84 eid[1] = pos - eid - 2; /* element length */
85
86 return pos;
87 }
88
89
90 /*
91 * This function is called when a station sends an association request with
92 * WMM info element. The function returns 1 on success or 0 on any error in WMM
93 * element. eid does not include Element ID and Length octets.
94 */
hostapd_eid_wmm_valid(struct hostapd_data * hapd,const u8 * eid,size_t len)95 int hostapd_eid_wmm_valid(struct hostapd_data *hapd, const u8 *eid, size_t len)
96 {
97 struct wmm_information_element *wmm;
98
99 wpa_hexdump(MSG_MSGDUMP, "WMM IE", eid, len);
100
101 if (len < sizeof(struct wmm_information_element)) {
102 wpa_printf(MSG_DEBUG, "Too short WMM IE (len=%lu)",
103 (unsigned long) len);
104 return 0;
105 }
106
107 wmm = (struct wmm_information_element *) eid;
108 wpa_printf(MSG_DEBUG, "Validating WMM IE: OUI %02x:%02x:%02x "
109 "OUI type %d OUI sub-type %d version %d QoS info 0x%x",
110 wmm->oui[0], wmm->oui[1], wmm->oui[2], wmm->oui_type,
111 wmm->oui_subtype, wmm->version, wmm->qos_info);
112 if (wmm->oui_subtype != WMM_OUI_SUBTYPE_INFORMATION_ELEMENT ||
113 wmm->version != WMM_VERSION) {
114 wpa_printf(MSG_DEBUG, "Unsupported WMM IE Subtype/Version");
115 return 0;
116 }
117
118 return 1;
119 }
120
121
wmm_send_action(struct hostapd_data * hapd,const u8 * addr,const struct wmm_tspec_element * tspec,u8 action_code,u8 dialogue_token,u8 status_code)122 static void wmm_send_action(struct hostapd_data *hapd, const u8 *addr,
123 const struct wmm_tspec_element *tspec,
124 u8 action_code, u8 dialogue_token, u8 status_code)
125 {
126 u8 buf[256];
127 struct ieee80211_mgmt *m = (struct ieee80211_mgmt *) buf;
128 struct wmm_tspec_element *t = (struct wmm_tspec_element *)
129 m->u.action.u.wmm_action.variable;
130 int len;
131
132 hostapd_logger(hapd, addr, HOSTAPD_MODULE_IEEE80211,
133 HOSTAPD_LEVEL_DEBUG,
134 "action response - reason %d", status_code);
135 os_memset(buf, 0, sizeof(buf));
136 m->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
137 WLAN_FC_STYPE_ACTION);
138 os_memcpy(m->da, addr, ETH_ALEN);
139 os_memcpy(m->sa, hapd->own_addr, ETH_ALEN);
140 os_memcpy(m->bssid, hapd->own_addr, ETH_ALEN);
141 m->u.action.category = WLAN_ACTION_WMM;
142 m->u.action.u.wmm_action.action_code = action_code;
143 m->u.action.u.wmm_action.dialog_token = dialogue_token;
144 m->u.action.u.wmm_action.status_code = status_code;
145 os_memcpy(t, tspec, sizeof(struct wmm_tspec_element));
146 len = ((u8 *) (t + 1)) - buf;
147
148 if (hostapd_drv_send_mlme(hapd, m, len, 0) < 0)
149 wpa_printf(MSG_INFO, "wmm_send_action: send failed");
150 }
151
152
wmm_process_tspec(struct wmm_tspec_element * tspec)153 int wmm_process_tspec(struct wmm_tspec_element *tspec)
154 {
155 u64 medium_time;
156 unsigned int pps, duration;
157 unsigned int up, psb, dir, tid;
158 u16 val, surplus;
159
160 up = (tspec->ts_info[1] >> 3) & 0x07;
161 psb = (tspec->ts_info[1] >> 2) & 0x01;
162 dir = (tspec->ts_info[0] >> 5) & 0x03;
163 tid = (tspec->ts_info[0] >> 1) & 0x0f;
164 wpa_printf(MSG_DEBUG, "WMM: TS Info: UP=%d PSB=%d Direction=%d TID=%d",
165 up, psb, dir, tid);
166 val = le_to_host16(tspec->nominal_msdu_size);
167 wpa_printf(MSG_DEBUG, "WMM: Nominal MSDU Size: %d%s",
168 val & 0x7fff, val & 0x8000 ? " (fixed)" : "");
169 wpa_printf(MSG_DEBUG, "WMM: Mean Data Rate: %u bps",
170 le_to_host32(tspec->mean_data_rate));
171 wpa_printf(MSG_DEBUG, "WMM: Minimum PHY Rate: %u bps",
172 le_to_host32(tspec->minimum_phy_rate));
173 val = le_to_host16(tspec->surplus_bandwidth_allowance);
174 wpa_printf(MSG_DEBUG, "WMM: Surplus Bandwidth Allowance: %u.%04u",
175 val >> 13, 10000 * (val & 0x1fff) / 0x2000);
176
177 val = le_to_host16(tspec->nominal_msdu_size);
178 if (val == 0) {
179 wpa_printf(MSG_DEBUG, "WMM: Invalid Nominal MSDU Size (0)");
180 return WMM_ADDTS_STATUS_INVALID_PARAMETERS;
181 }
182 /* pps = Ceiling((Mean Data Rate / 8) / Nominal MSDU Size) */
183 pps = ((le_to_host32(tspec->mean_data_rate) / 8) + val - 1) / val;
184 wpa_printf(MSG_DEBUG, "WMM: Packets-per-second estimate for TSPEC: %d",
185 pps);
186
187 if (le_to_host32(tspec->minimum_phy_rate) < 1000000) {
188 wpa_printf(MSG_DEBUG, "WMM: Too small Minimum PHY Rate");
189 return WMM_ADDTS_STATUS_INVALID_PARAMETERS;
190 }
191
192 duration = (le_to_host16(tspec->nominal_msdu_size) & 0x7fff) * 8 /
193 (le_to_host32(tspec->minimum_phy_rate) / 1000000) +
194 50 /* FIX: proper SIFS + ACK duration */;
195
196 /* unsigned binary number with an implicit binary point after the
197 * leftmost 3 bits, i.e., 0x2000 = 1.0 */
198 surplus = le_to_host16(tspec->surplus_bandwidth_allowance);
199 if (surplus <= 0x2000) {
200 wpa_printf(MSG_DEBUG, "WMM: Surplus Bandwidth Allowance not "
201 "greater than unity");
202 return WMM_ADDTS_STATUS_INVALID_PARAMETERS;
203 }
204
205 medium_time = (u64) surplus * pps * duration / 0x2000;
206 wpa_printf(MSG_DEBUG, "WMM: Estimated medium time: %lu",
207 (unsigned long) medium_time);
208
209 /*
210 * TODO: store list of granted (and still active) TSPECs and check
211 * whether there is available medium time for this request. For now,
212 * just refuse requests that would by themselves take very large
213 * portion of the available bandwidth.
214 */
215 if (medium_time > 750000) {
216 wpa_printf(MSG_DEBUG, "WMM: Refuse TSPEC request for over "
217 "75%% of available bandwidth");
218 return WMM_ADDTS_STATUS_REFUSED;
219 }
220
221 /* Convert to 32 microseconds per second unit */
222 tspec->medium_time = host_to_le16(medium_time / 32);
223
224 return WMM_ADDTS_STATUS_ADMISSION_ACCEPTED;
225 }
226
227
wmm_addts_req(struct hostapd_data * hapd,const struct ieee80211_mgmt * mgmt,struct wmm_tspec_element * tspec,size_t len)228 static void wmm_addts_req(struct hostapd_data *hapd,
229 const struct ieee80211_mgmt *mgmt,
230 struct wmm_tspec_element *tspec, size_t len)
231 {
232 const u8 *end = ((const u8 *) mgmt) + len;
233 int res;
234
235 if ((const u8 *) (tspec + 1) > end) {
236 wpa_printf(MSG_DEBUG, "WMM: TSPEC overflow in ADDTS Request");
237 return;
238 }
239
240 wpa_printf(MSG_DEBUG, "WMM: ADDTS Request (Dialog Token %d) for TSPEC "
241 "from " MACSTR,
242 mgmt->u.action.u.wmm_action.dialog_token,
243 MAC2STR(mgmt->sa));
244
245 res = wmm_process_tspec(tspec);
246 wpa_printf(MSG_DEBUG, "WMM: ADDTS processing result: %d", res);
247
248 wmm_send_action(hapd, mgmt->sa, tspec, WMM_ACTION_CODE_ADDTS_RESP,
249 mgmt->u.action.u.wmm_action.dialog_token, res);
250 }
251
252
hostapd_wmm_action(struct hostapd_data * hapd,const struct ieee80211_mgmt * mgmt,size_t len)253 void hostapd_wmm_action(struct hostapd_data *hapd,
254 const struct ieee80211_mgmt *mgmt, size_t len)
255 {
256 int action_code;
257 int left = len - IEEE80211_HDRLEN - 4;
258 const u8 *pos = ((const u8 *) mgmt) + IEEE80211_HDRLEN + 4;
259 struct ieee802_11_elems elems;
260 struct sta_info *sta = ap_get_sta(hapd, mgmt->sa);
261
262 /* check that the request comes from a valid station */
263 if (!sta ||
264 (sta->flags & (WLAN_STA_ASSOC | WLAN_STA_WMM)) !=
265 (WLAN_STA_ASSOC | WLAN_STA_WMM)) {
266 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
267 HOSTAPD_LEVEL_DEBUG,
268 "wmm action received is not from associated wmm"
269 " station");
270 /* TODO: respond with action frame refused status code */
271 return;
272 }
273
274 if (left < 0)
275 return; /* not a valid WMM Action frame */
276
277 /* extract the tspec info element */
278 if (ieee802_11_parse_elems(pos, left, &elems, 1) == ParseFailed) {
279 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
280 HOSTAPD_LEVEL_DEBUG,
281 "hostapd_wmm_action - could not parse wmm "
282 "action");
283 /* TODO: respond with action frame invalid parameters status
284 * code */
285 return;
286 }
287
288 if (!elems.wmm_tspec ||
289 elems.wmm_tspec_len != (sizeof(struct wmm_tspec_element) - 2)) {
290 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
291 HOSTAPD_LEVEL_DEBUG,
292 "hostapd_wmm_action - missing or wrong length "
293 "tspec");
294 /* TODO: respond with action frame invalid parameters status
295 * code */
296 return;
297 }
298
299 /* TODO: check the request is for an AC with ACM set, if not, refuse
300 * request */
301
302 action_code = mgmt->u.action.u.wmm_action.action_code;
303 switch (action_code) {
304 case WMM_ACTION_CODE_ADDTS_REQ:
305 wmm_addts_req(hapd, mgmt, (struct wmm_tspec_element *)
306 (elems.wmm_tspec - 2), len);
307 return;
308 #if 0
309 /* TODO: needed for client implementation */
310 case WMM_ACTION_CODE_ADDTS_RESP:
311 wmm_setup_request(hapd, mgmt, len);
312 return;
313 /* TODO: handle station teardown requests */
314 case WMM_ACTION_CODE_DELTS:
315 wmm_teardown(hapd, mgmt, len);
316 return;
317 #endif
318 }
319
320 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
321 HOSTAPD_LEVEL_DEBUG,
322 "hostapd_wmm_action - unknown action code %d",
323 action_code);
324 }
325