wpa_supplicant/bss.c

   1 /*
   2  * BSS table
   3  * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "utils/includes.h"
  16
  17 #include "utils/common.h"
  18 #include "utils/eloop.h"
  19 #include "common/ieee802_11_defs.h"
  20 #include "drivers/driver.h"
  21 #include "wpa_supplicant_i.h"
  22 #include "notify.h"
  23 #include "scan.h"
  24 #include "bss.h"
  25
  26
  27 #ifndef WPA_BSS_MAX_COUNT
  28 #define WPA_BSS_MAX_COUNT 200
  29 #endif /* WPA_BSS_MAX_COUNT */
  30
  31 /**
  32  * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
  33  */
  34 #define WPA_BSS_EXPIRATION_PERIOD 10
  35
  36 /**
  37  * WPA_BSS_EXPIRATION_AGE - BSS entry age after which it can be expired
  38  *
  39  * This value control the time in seconds after which a BSS entry gets removed
  40  * if it has not been updated or is not in use.
  41  */
  42 #define WPA_BSS_EXPIRATION_AGE 180
  43
  44 /**
  45  * WPA_BSS_EXPIRATION_SCAN_COUNT - Expire BSS after number of scans
  46  *
  47  * If the BSS entry has not been seen in this many scans, it will be removed.
  48  * Value 1 means that the entry is removed after the first scan without the
  49  * BSSID being seen. Larger values can be used to avoid BSS entries
  50  * disappearing if they are not visible in every scan (e.g., low signal quality
  51  * or interference).
  52  */
  53 #define WPA_BSS_EXPIRATION_SCAN_COUNT 2
  54
  55 #define WPA_BSS_FREQ_CHANGED_FLAG       BIT(0)
  56 #define WPA_BSS_SIGNAL_CHANGED_FLAG     BIT(1)
  57 #define WPA_BSS_PRIVACY_CHANGED_FLAG    BIT(2)
  58 #define WPA_BSS_MODE_CHANGED_FLAG       BIT(3)
  59 #define WPA_BSS_WPAIE_CHANGED_FLAG      BIT(4)
  60 #define WPA_BSS_RSNIE_CHANGED_FLAG      BIT(5)
  61 #define WPA_BSS_WPS_CHANGED_FLAG        BIT(6)
  62 #define WPA_BSS_RATES_CHANGED_FLAG      BIT(7)
  63
  64
  65 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
  66 {
  67         dl_list_del(&bss->list);
  68         dl_list_del(&bss->list_id);
  69         wpa_s->num_bss--;
  70         wpa_printf(MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR " SSID '%s'",
  71                    bss->id, MAC2STR(bss->bssid),
  72                    wpa_ssid_txt(bss->ssid, bss->ssid_len));
  73         wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
  74         os_free(bss);
  75 }
  76
  77
  78 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
  79                              const u8 *ssid, size_t ssid_len)
  80 {
  81         struct wpa_bss *bss;
  82         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
  83                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
  84                     bss->ssid_len == ssid_len &&
  85                     os_memcmp(bss->ssid, ssid, ssid_len) == 0)
  86                         return bss;
  87         }
  88         return NULL;
  89 }
  90
  91
  92 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
  93 {
  94         os_time_t usec;
  95
  96         dst->flags = src->flags;
  97         os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
  98         dst->freq = src->freq;
  99         dst->beacon_int = src->beacon_int;
 100         dst->caps = src->caps;
 101         dst->qual = src->qual;
 102         dst->noise = src->noise;
 103         dst->level = src->level;
 104         dst->tsf = src->tsf;
 105
 106         os_get_time(&dst->last_update);
 107         dst->last_update.sec -= src->age / 1000;
 108         usec = (src->age % 1000) * 1000;
 109         if (dst->last_update.usec < usec) {
 110                 dst->last_update.sec--;
 111                 dst->last_update.usec += 1000000;
 112         }
 113         dst->last_update.usec -= usec;
 114 }
 115
 116
 117 static void wpa_bss_add(struct wpa_supplicant *wpa_s,
 118                         const u8 *ssid, size_t ssid_len,
 119                         struct wpa_scan_res *res)
 120 {
 121         struct wpa_bss *bss;
 122
 123         bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
 124         if (bss == NULL)
 125                 return;
 126         bss->id = wpa_s->bss_next_id++;
 127         bss->last_update_idx = wpa_s->bss_update_idx;
 128         wpa_bss_copy_res(bss, res);
 129         os_memcpy(bss->ssid, ssid, ssid_len);
 130         bss->ssid_len = ssid_len;
 131         bss->ie_len = res->ie_len;
 132         bss->beacon_ie_len = res->beacon_ie_len;
 133         os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 134
 135         dl_list_add_tail(&wpa_s->bss, &bss->list);
 136         dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
 137         wpa_s->num_bss++;
 138         wpa_printf(MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR " SSID '%s'",
 139                    bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
 140         wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
 141         if (wpa_s->num_bss > WPA_BSS_MAX_COUNT) {
 142                 /* Remove the oldest entry */
 143                 wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
 144                                                     struct wpa_bss, list));
 145         }
 146 }
 147
 148
 149 static int are_ies_equal(const struct wpa_bss *old,
 150                          const struct wpa_scan_res *new, u32 ie)
 151 {
 152         const u8 *old_ie, *new_ie;
 153         struct wpabuf *old_ie_buff = NULL;
 154         struct wpabuf *new_ie_buff = NULL;
 155         int new_ie_len, old_ie_len, ret, is_multi;
 156
 157         switch (ie) {
 158         case WPA_IE_VENDOR_TYPE:
 159                 old_ie = wpa_bss_get_vendor_ie(old, ie);
 160                 new_ie = wpa_scan_get_vendor_ie(new, ie);
 161                 is_multi = 0;
 162                 break;
 163         case WPS_IE_VENDOR_TYPE:
 164                 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
 165                 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
 166                 is_multi = 1;
 167                 break;
 168         case WLAN_EID_RSN:
 169         case WLAN_EID_SUPP_RATES:
 170         case WLAN_EID_EXT_SUPP_RATES:
 171                 old_ie = wpa_bss_get_ie(old, ie);
 172                 new_ie = wpa_scan_get_ie(new, ie);
 173                 is_multi = 0;
 174                 break;
 175         default:
 176                 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
 177                 return 0;
 178         }
 179
 180         if (is_multi) {
 181                 /* in case of multiple IEs stored in buffer */
 182                 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
 183                 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
 184                 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
 185                 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
 186         } else {
 187                 /* in case of single IE */
 188                 old_ie_len = old_ie ? old_ie[1] + 2 : 0;
 189                 new_ie_len = new_ie ? new_ie[1] + 2 : 0;
 190         }
 191
 192         ret = (old_ie_len == new_ie_len &&
 193                os_memcmp(old_ie, new_ie, old_ie_len) == 0);
 194
 195         wpabuf_free(old_ie_buff);
 196         wpabuf_free(new_ie_buff);
 197
 198         return ret;
 199 }
 200
 201
 202 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
 203                                const struct wpa_scan_res *new)
 204 {
 205         u32 changes = 0;
 206         int caps_diff = old->caps ^ new->caps;
 207
 208         if (old->freq != new->freq)
 209                 changes |= WPA_BSS_FREQ_CHANGED_FLAG;
 210
 211         if (old->level != new->level)
 212                 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
 213
 214         if (caps_diff & IEEE80211_CAP_PRIVACY)
 215                 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
 216
 217         if (caps_diff & IEEE80211_CAP_IBSS)
 218                 changes |= WPA_BSS_MODE_CHANGED_FLAG;
 219
 220         if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
 221                 changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
 222
 223         if (!are_ies_equal(old, new, WLAN_EID_RSN))
 224                 changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
 225
 226         if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
 227                 changes |= WPA_BSS_WPS_CHANGED_FLAG;
 228
 229         if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
 230             !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
 231                 changes |= WPA_BSS_RATES_CHANGED_FLAG;
 232
 233         return changes;
 234 }
 235
 236
 237 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
 238                                const struct wpa_bss *bss)
 239 {
 240         if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
 241                 wpas_notify_bss_freq_changed(wpa_s, bss->id);
 242
 243         if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
 244                 wpas_notify_bss_signal_changed(wpa_s, bss->id);
 245
 246         if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
 247                 wpas_notify_bss_privacy_changed(wpa_s, bss->id);
 248
 249         if (changes & WPA_BSS_MODE_CHANGED_FLAG)
 250                 wpas_notify_bss_mode_changed(wpa_s, bss->id);
 251
 252         if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
 253                 wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
 254
 255         if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
 256                 wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
 257
 258         if (changes & WPA_BSS_WPS_CHANGED_FLAG)
 259                 wpas_notify_bss_wps_changed(wpa_s, bss->id);
 260
 261         if (changes & WPA_BSS_RATES_CHANGED_FLAG)
 262                 wpas_notify_bss_rates_changed(wpa_s, bss->id);
 263 }
 264
 265
 266 static void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
 267                            struct wpa_scan_res *res)
 268 {
 269         u32 changes;
 270
 271         changes = wpa_bss_compare_res(bss, res);
 272         bss->scan_miss_count = 0;
 273         bss->last_update_idx = wpa_s->bss_update_idx;
 274         wpa_bss_copy_res(bss, res);
 275         /* Move the entry to the end of the list */
 276         dl_list_del(&bss->list);
 277         if (bss->ie_len + bss->beacon_ie_len >=
 278             res->ie_len + res->beacon_ie_len) {
 279                 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 280                 bss->ie_len = res->ie_len;
 281                 bss->beacon_ie_len = res->beacon_ie_len;
 282         } else {
 283                 struct wpa_bss *nbss;
 284                 struct dl_list *prev = bss->list_id.prev;
 285                 dl_list_del(&bss->list_id);
 286                 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
 287                                   res->beacon_ie_len);
 288                 if (nbss) {
 289                         bss = nbss;
 290                         os_memcpy(bss + 1, res + 1,
 291                                   res->ie_len + res->beacon_ie_len);
 292                         bss->ie_len = res->ie_len;
 293                         bss->beacon_ie_len = res->beacon_ie_len;
 294                 }
 295                 dl_list_add(prev, &bss->list_id);
 296         }
 297         dl_list_add_tail(&wpa_s->bss, &bss->list);
 298
 299         notify_bss_changes(wpa_s, changes, bss);
 300 }
 301
 302
 303 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 304 {
 305         return bss == wpa_s->current_bss ||
 306                 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
 307                 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
 308 }
 309
 310
 311 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
 312 {
 313         wpa_s->bss_update_idx++;
 314         wpa_printf(MSG_DEBUG, "BSS: Start scan result update %u",
 315                    wpa_s->bss_update_idx);
 316 }
 317
 318
 319 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
 320                              struct wpa_scan_res *res)
 321 {
 322         const u8 *ssid;
 323         struct wpa_bss *bss;
 324
 325         ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
 326         if (ssid == NULL) {
 327                 wpa_printf(MSG_DEBUG, "BSS: No SSID IE included for " MACSTR,
 328                            MAC2STR(res->bssid));
 329                 return;
 330         }
 331         if (ssid[1] > 32) {
 332                 wpa_printf(MSG_DEBUG, "BSS: Too long SSID IE included for "
 333                            MACSTR, MAC2STR(res->bssid));
 334                 return;
 335         }
 336
 337         /* TODO: add option for ignoring BSSes we are not interested in
 338          * (to save memory) */
 339         bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
 340         if (bss == NULL)
 341                 wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
 342         else
 343                 wpa_bss_update(wpa_s, bss, res);
 344 }
 345
 346
 347 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
 348                                     const struct scan_info *info)
 349 {
 350         int found;
 351         size_t i;
 352
 353         if (info == NULL)
 354                 return 1;
 355
 356         if (info->num_freqs) {
 357                 found = 0;
 358                 for (i = 0; i < info->num_freqs; i++) {
 359                         if (bss->freq == info->freqs[i]) {
 360                                 found = 1;
 361                                 break;
 362                         }
 363                 }
 364                 if (!found)
 365                         return 0;
 366         }
 367
 368         if (info->num_ssids) {
 369                 found = 0;
 370                 for (i = 0; i < info->num_ssids; i++) {
 371                         const struct wpa_driver_scan_ssid *s = &info->ssids[i];
 372                         if ((s->ssid == NULL || s->ssid_len == 0) ||
 373                             (s->ssid_len == bss->ssid_len &&
 374                              os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
 375                              0)) {
 376                                 found = 1;
 377                                 break;
 378                         }
 379                 }
 380                 if (!found)
 381                         return 0;
 382         }
 383
 384         return 1;
 385 }
 386
 387
 388 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
 389                         int new_scan)
 390 {
 391         struct wpa_bss *bss, *n;
 392
 393         if (!new_scan)
 394                 return; /* do not expire entries without new scan */
 395
 396         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 397                 if (wpa_bss_in_use(wpa_s, bss))
 398                         continue;
 399                 if (!wpa_bss_included_in_scan(bss, info))
 400                         continue; /* expire only BSSes that were scanned */
 401                 if (bss->last_update_idx < wpa_s->bss_update_idx)
 402                         bss->scan_miss_count++;
 403                 if (bss->scan_miss_count >= WPA_BSS_EXPIRATION_SCAN_COUNT) {
 404                         wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to no "
 405                                    "match in scan", bss->id);
 406                         wpa_bss_remove(wpa_s, bss);
 407                 }
 408         }
 409 }
 410
 411
 412 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
 413 {
 414         struct wpa_supplicant *wpa_s = eloop_ctx;
 415         struct wpa_bss *bss, *n;
 416         struct os_time t;
 417
 418         if (dl_list_empty(&wpa_s->bss))
 419                 return;
 420
 421         os_get_time(&t);
 422         t.sec -= WPA_BSS_EXPIRATION_AGE;
 423
 424         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 425                 if (wpa_bss_in_use(wpa_s, bss))
 426                         continue;
 427
 428                 if (os_time_before(&bss->last_update, &t)) {
 429                         wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to age",
 430                                    bss->id);
 431                         wpa_bss_remove(wpa_s, bss);
 432                 } else
 433                         break;
 434         }
 435         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 436                                wpa_bss_timeout, wpa_s, NULL);
 437 }
 438
 439
 440 int wpa_bss_init(struct wpa_supplicant *wpa_s)
 441 {
 442         dl_list_init(&wpa_s->bss);
 443         dl_list_init(&wpa_s->bss_id);
 444         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 445                                wpa_bss_timeout, wpa_s, NULL);
 446         return 0;
 447 }
 448
 449
 450 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
 451 {
 452         struct wpa_bss *bss, *n;
 453         eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
 454         if (wpa_s->bss.next == NULL)
 455                 return; /* BSS table not yet initialized */
 456         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list)
 457                 wpa_bss_remove(wpa_s, bss);
 458 }
 459
 460
 461 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
 462                                    const u8 *bssid)
 463 {
 464         struct wpa_bss *bss;
 465         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 466                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
 467                         return bss;
 468         }
 469         return NULL;
 470 }
 471
 472
 473 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
 474 {
 475         struct wpa_bss *bss;
 476         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 477                 if (bss->id == id)
 478                         return bss;
 479         }
 480         return NULL;
 481 }
 482
 483
 484 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
 485 {
 486         const u8 *end, *pos;
 487
 488         pos = (const u8 *) (bss + 1);
 489         end = pos + bss->ie_len;
 490
 491         while (pos + 1 < end) {
 492                 if (pos + 2 + pos[1] > end)
 493                         break;
 494                 if (pos[0] == ie)
 495                         return pos;
 496                 pos += 2 + pos[1];
 497         }
 498
 499         return NULL;
 500 }
 501
 502
 503 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
 504 {
 505         const u8 *end, *pos;
 506
 507         pos = (const u8 *) (bss + 1);
 508         end = pos + bss->ie_len;
 509
 510         while (pos + 1 < end) {
 511                 if (pos + 2 + pos[1] > end)
 512                         break;
 513                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 514                     vendor_type == WPA_GET_BE32(&pos[2]))
 515                         return pos;
 516                 pos += 2 + pos[1];
 517         }
 518
 519         return NULL;
 520 }
 521
 522
 523 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
 524                                             u32 vendor_type)
 525 {
 526         struct wpabuf *buf;
 527         const u8 *end, *pos;
 528
 529         buf = wpabuf_alloc(bss->ie_len);
 530         if (buf == NULL)
 531                 return NULL;
 532
 533         pos = (const u8 *) (bss + 1);
 534         end = pos + bss->ie_len;
 535
 536         while (pos + 1 < end) {
 537                 if (pos + 2 + pos[1] > end)
 538                         break;
 539                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 540                     vendor_type == WPA_GET_BE32(&pos[2]))
 541                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
 542                 pos += 2 + pos[1];
 543         }
 544
 545         if (wpabuf_len(buf) == 0) {
 546                 wpabuf_free(buf);
 547                 buf = NULL;
 548         }
 549
 550         return buf;
 551 }
 552
 553
 554 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
 555 {
 556         int rate = 0;
 557         const u8 *ie;
 558         int i;
 559
 560         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 561         for (i = 0; ie && i < ie[1]; i++) {
 562                 if ((ie[i + 2] & 0x7f) > rate)
 563                         rate = ie[i + 2] & 0x7f;
 564         }
 565
 566         ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 567         for (i = 0; ie && i < ie[1]; i++) {
 568                 if ((ie[i + 2] & 0x7f) > rate)
 569                         rate = ie[i + 2] & 0x7f;
 570         }
 571
 572         return rate;
 573 }
 574
 575
 576 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
 577 {
 578         const u8 *ie, *ie2;
 579         int i, j;
 580         unsigned int len;
 581         u8 *r;
 582
 583         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 584         ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 585
 586         len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
 587
 588         r = os_malloc(len);
 589         if (!r)
 590                 return -1;
 591
 592         for (i = 0; ie && i < ie[1]; i++)
 593                 r[i] = ie[i + 2] & 0x7f;
 594
 595         for (j = 0; ie2 && j < ie2[1]; j++)
 596                 r[i + j] = ie2[j + 2] & 0x7f;
 597
 598         *rates = r;
 599         return len;
 600 }