wmm.c revision 346981
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 24static 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 35static 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 */ 46u8 * 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 */ 95int 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 122static 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 153int 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 228static 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 253void 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