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 program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * Alternatively, this software may be distributed under the terms of BSD 12 * license. 13 * 14 * See README and COPYING for more details. 15 */ 16 17 #include "utils/includes.h" 18 19 #include "utils/common.h" 20 #include "common/ieee802_11_defs.h" 21 #include "common/ieee802_11_common.h" 22 #include "hostapd.h" 23 #include "ieee802_11.h" 24 #include "sta_info.h" 25 #include "ap_config.h" 26 #include "ap_drv_ops.h" 27 #include "wmm.h" 28 29 30 /* TODO: maintain separate sequence and fragment numbers for each AC 31 * TODO: IGMP snooping to track which multicasts to forward - and use QOS-DATA 32 * if only WMM stations are receiving a certain group */ 33 34 35 static inline u8 wmm_aci_aifsn(int aifsn, int acm, int aci) 36 { 37 u8 ret; 38 ret = (aifsn << WMM_AC_AIFNS_SHIFT) & WMM_AC_AIFSN_MASK; 39 if (acm) 40 ret |= WMM_AC_ACM; 41 ret |= (aci << WMM_AC_ACI_SHIFT) & WMM_AC_ACI_MASK; 42 return ret; 43 } 44 45 46 static inline u8 wmm_ecw(int ecwmin, int ecwmax) 47 { 48 return ((ecwmin << WMM_AC_ECWMIN_SHIFT) & WMM_AC_ECWMIN_MASK) | 49 ((ecwmax << WMM_AC_ECWMAX_SHIFT) & WMM_AC_ECWMAX_MASK); 50 } 51 52 53 /* 54 * Add WMM Parameter Element to Beacon, Probe Response, and (Re)Association 55 * Response frames. 56 */ 57 u8 * hostapd_eid_wmm(struct hostapd_data *hapd, u8 *eid) 58 { 59 u8 *pos = eid; 60 struct wmm_parameter_element *wmm = 61 (struct wmm_parameter_element *) (pos + 2); 62 int e; 63 64 if (!hapd->conf->wmm_enabled) 65 return eid; 66 eid[0] = WLAN_EID_VENDOR_SPECIFIC; 67 wmm->oui[0] = 0x00; 68 wmm->oui[1] = 0x50; 69 wmm->oui[2] = 0xf2; 70 wmm->oui_type = WMM_OUI_TYPE; 71 wmm->oui_subtype = WMM_OUI_SUBTYPE_PARAMETER_ELEMENT; 72 wmm->version = WMM_VERSION; 73 wmm->qos_info = hapd->parameter_set_count & 0xf; 74 75 if (hapd->conf->wmm_uapsd) 76 wmm->qos_info |= 0x80; 77 78 wmm->reserved = 0; 79 80 /* fill in a parameter set record for each AC */ 81 for (e = 0; e < 4; e++) { 82 struct wmm_ac_parameter *ac = &wmm->ac[e]; 83 struct hostapd_wmm_ac_params *acp = 84 &hapd->iconf->wmm_ac_params[e]; 85 86 ac->aci_aifsn = wmm_aci_aifsn(acp->aifs, 87 acp->admission_control_mandatory, 88 e); 89 ac->cw = wmm_ecw(acp->cwmin, acp->cwmax); 90 ac->txop_limit = host_to_le16(acp->txop_limit); 91 } 92 93 pos = (u8 *) (wmm + 1); 94 eid[1] = pos - eid - 2; /* element length */ 95 96 return pos; 97 } 98 99 100 /* 101 * This function is called when a station sends an association request with 102 * WMM info element. The function returns 1 on success or 0 on any error in WMM 103 * element. eid does not include Element ID and Length octets. 104 */ 105 int hostapd_eid_wmm_valid(struct hostapd_data *hapd, const u8 *eid, size_t len) 106 { 107 struct wmm_information_element *wmm; 108 109 wpa_hexdump(MSG_MSGDUMP, "WMM IE", eid, len); 110 111 if (len < sizeof(struct wmm_information_element)) { 112 wpa_printf(MSG_DEBUG, "Too short WMM IE (len=%lu)", 113 (unsigned long) len); 114 return 0; 115 } 116 117 wmm = (struct wmm_information_element *) eid; 118 wpa_printf(MSG_DEBUG, "Validating WMM IE: OUI %02x:%02x:%02x " 119 "OUI type %d OUI sub-type %d version %d QoS info 0x%x", 120 wmm->oui[0], wmm->oui[1], wmm->oui[2], wmm->oui_type, 121 wmm->oui_subtype, wmm->version, wmm->qos_info); 122 if (wmm->oui_subtype != WMM_OUI_SUBTYPE_INFORMATION_ELEMENT || 123 wmm->version != WMM_VERSION) { 124 wpa_printf(MSG_DEBUG, "Unsupported WMM IE Subtype/Version"); 125 return 0; 126 } 127 128 return 1; 129 } 130 131 132 static void wmm_send_action(struct hostapd_data *hapd, const u8 *addr, 133 const struct wmm_tspec_element *tspec, 134 u8 action_code, u8 dialogue_token, u8 status_code) 135 { 136 u8 buf[256]; 137 struct ieee80211_mgmt *m = (struct ieee80211_mgmt *) buf; 138 struct wmm_tspec_element *t = (struct wmm_tspec_element *) 139 m->u.action.u.wmm_action.variable; 140 int len; 141 142 hostapd_logger(hapd, addr, HOSTAPD_MODULE_IEEE80211, 143 HOSTAPD_LEVEL_DEBUG, 144 "action response - reason %d", status_code); 145 os_memset(buf, 0, sizeof(buf)); 146 m->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT, 147 WLAN_FC_STYPE_ACTION); 148 os_memcpy(m->da, addr, ETH_ALEN); 149 os_memcpy(m->sa, hapd->own_addr, ETH_ALEN); 150 os_memcpy(m->bssid, hapd->own_addr, ETH_ALEN); 151 m->u.action.category = WLAN_ACTION_WMM; 152 m->u.action.u.wmm_action.action_code = action_code; 153 m->u.action.u.wmm_action.dialog_token = dialogue_token; 154 m->u.action.u.wmm_action.status_code = status_code; 155 os_memcpy(t, tspec, sizeof(struct wmm_tspec_element)); 156 len = ((u8 *) (t + 1)) - buf; 157 158 if (hostapd_drv_send_mlme(hapd, m, len) < 0) 159 perror("wmm_send_action: send"); 160 } 161 162 163 int wmm_process_tspec(struct wmm_tspec_element *tspec) 164 { 165 int medium_time, pps, duration; 166 int up, psb, dir, tid; 167 u16 val, surplus; 168 169 up = (tspec->ts_info[1] >> 3) & 0x07; 170 psb = (tspec->ts_info[1] >> 2) & 0x01; 171 dir = (tspec->ts_info[0] >> 5) & 0x03; 172 tid = (tspec->ts_info[0] >> 1) & 0x0f; 173 wpa_printf(MSG_DEBUG, "WMM: TS Info: UP=%d PSB=%d Direction=%d TID=%d", 174 up, psb, dir, tid); 175 val = le_to_host16(tspec->nominal_msdu_size); 176 wpa_printf(MSG_DEBUG, "WMM: Nominal MSDU Size: %d%s", 177 val & 0x7fff, val & 0x8000 ? " (fixed)" : ""); 178 wpa_printf(MSG_DEBUG, "WMM: Mean Data Rate: %u bps", 179 le_to_host32(tspec->mean_data_rate)); 180 wpa_printf(MSG_DEBUG, "WMM: Minimum PHY Rate: %u bps", 181 le_to_host32(tspec->minimum_phy_rate)); 182 val = le_to_host16(tspec->surplus_bandwidth_allowance); 183 wpa_printf(MSG_DEBUG, "WMM: Surplus Bandwidth Allowance: %u.%04u", 184 val >> 13, 10000 * (val & 0x1fff) / 0x2000); 185 186 val = le_to_host16(tspec->nominal_msdu_size); 187 if (val == 0) { 188 wpa_printf(MSG_DEBUG, "WMM: Invalid Nominal MSDU Size (0)"); 189 return WMM_ADDTS_STATUS_INVALID_PARAMETERS; 190 } 191 /* pps = Ceiling((Mean Data Rate / 8) / Nominal MSDU Size) */ 192 pps = ((le_to_host32(tspec->mean_data_rate) / 8) + val - 1) / val; 193 wpa_printf(MSG_DEBUG, "WMM: Packets-per-second estimate for TSPEC: %d", 194 pps); 195 196 if (le_to_host32(tspec->minimum_phy_rate) < 1000000) { 197 wpa_printf(MSG_DEBUG, "WMM: Too small Minimum PHY Rate"); 198 return WMM_ADDTS_STATUS_INVALID_PARAMETERS; 199 } 200 201 duration = (le_to_host16(tspec->nominal_msdu_size) & 0x7fff) * 8 / 202 (le_to_host32(tspec->minimum_phy_rate) / 1000000) + 203 50 /* FIX: proper SIFS + ACK duration */; 204 205 /* unsigned binary number with an implicit binary point after the 206 * leftmost 3 bits, i.e., 0x2000 = 1.0 */ 207 surplus = le_to_host16(tspec->surplus_bandwidth_allowance); 208 if (surplus <= 0x2000) { 209 wpa_printf(MSG_DEBUG, "WMM: Surplus Bandwidth Allowance not " 210 "greater than unity"); 211 return WMM_ADDTS_STATUS_INVALID_PARAMETERS; 212 } 213 214 medium_time = surplus * pps * duration / 0x2000; 215 wpa_printf(MSG_DEBUG, "WMM: Estimated medium time: %u", medium_time); 216 217 /* 218 * TODO: store list of granted (and still active) TSPECs and check 219 * whether there is available medium time for this request. For now, 220 * just refuse requests that would by themselves take very large 221 * portion of the available bandwidth. 222 */ 223 if (medium_time > 750000) { 224 wpa_printf(MSG_DEBUG, "WMM: Refuse TSPEC request for over " 225 "75%% of available bandwidth"); 226 return WMM_ADDTS_STATUS_REFUSED; 227 } 228 229 /* Convert to 32 microseconds per second unit */ 230 tspec->medium_time = host_to_le16(medium_time / 32); 231 232 return WMM_ADDTS_STATUS_ADMISSION_ACCEPTED; 233 } 234 235 236 static void wmm_addts_req(struct hostapd_data *hapd, 237 const struct ieee80211_mgmt *mgmt, 238 struct wmm_tspec_element *tspec, size_t len) 239 { 240 const u8 *end = ((const u8 *) mgmt) + len; 241 int res; 242 243 if ((const u8 *) (tspec + 1) > end) { 244 wpa_printf(MSG_DEBUG, "WMM: TSPEC overflow in ADDTS Request"); 245 return; 246 } 247 248 wpa_printf(MSG_DEBUG, "WMM: ADDTS Request (Dialog Token %d) for TSPEC " 249 "from " MACSTR, 250 mgmt->u.action.u.wmm_action.dialog_token, 251 MAC2STR(mgmt->sa)); 252 253 res = wmm_process_tspec(tspec); 254 wpa_printf(MSG_DEBUG, "WMM: ADDTS processing result: %d", res); 255 256 wmm_send_action(hapd, mgmt->sa, tspec, WMM_ACTION_CODE_ADDTS_RESP, 257 mgmt->u.action.u.wmm_action.dialog_token, res); 258 } 259 260 261 void hostapd_wmm_action(struct hostapd_data *hapd, 262 const struct ieee80211_mgmt *mgmt, size_t len) 263 { 264 int action_code; 265 int left = len - IEEE80211_HDRLEN - 4; 266 const u8 *pos = ((const u8 *) mgmt) + IEEE80211_HDRLEN + 4; 267 struct ieee802_11_elems elems; 268 struct sta_info *sta = ap_get_sta(hapd, mgmt->sa); 269 270 /* check that the request comes from a valid station */ 271 if (!sta || 272 (sta->flags & (WLAN_STA_ASSOC | WLAN_STA_WMM)) != 273 (WLAN_STA_ASSOC | WLAN_STA_WMM)) { 274 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 275 HOSTAPD_LEVEL_DEBUG, 276 "wmm action received is not from associated wmm" 277 " station"); 278 /* TODO: respond with action frame refused status code */ 279 return; 280 } 281 282 /* extract the tspec info element */ 283 if (ieee802_11_parse_elems(pos, left, &elems, 1) == ParseFailed) { 284 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 285 HOSTAPD_LEVEL_DEBUG, 286 "hostapd_wmm_action - could not parse wmm " 287 "action"); 288 /* TODO: respond with action frame invalid parameters status 289 * code */ 290 return; 291 } 292 293 if (!elems.wmm_tspec || 294 elems.wmm_tspec_len != (sizeof(struct wmm_tspec_element) - 2)) { 295 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 296 HOSTAPD_LEVEL_DEBUG, 297 "hostapd_wmm_action - missing or wrong length " 298 "tspec"); 299 /* TODO: respond with action frame invalid parameters status 300 * code */ 301 return; 302 } 303 304 /* TODO: check the request is for an AC with ACM set, if not, refuse 305 * request */ 306 307 action_code = mgmt->u.action.u.wmm_action.action_code; 308 switch (action_code) { 309 case WMM_ACTION_CODE_ADDTS_REQ: 310 wmm_addts_req(hapd, mgmt, (struct wmm_tspec_element *) 311 (elems.wmm_tspec - 2), len); 312 return; 313 #if 0 314 /* TODO: needed for client implementation */ 315 case WMM_ACTION_CODE_ADDTS_RESP: 316 wmm_setup_request(hapd, mgmt, len); 317 return; 318 /* TODO: handle station teardown requests */ 319 case WMM_ACTION_CODE_DELTS: 320 wmm_teardown(hapd, mgmt, len); 321 return; 322 #endif 323 } 324 325 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 326 HOSTAPD_LEVEL_DEBUG, 327 "hostapd_wmm_action - unknown action code %d", 328 action_code); 329 } 330