1 /* 2 * Copyright 2002-2005, Instant802 Networks, Inc. 3 * Copyright 2005-2006, Devicescape Software, Inc. 4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> 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 12 #include <linux/kernel.h> 13 #include <linux/skbuff.h> 14 #include <linux/netdevice.h> 15 #include <linux/etherdevice.h> 16 #include <linux/rcupdate.h> 17 #include <net/mac80211.h> 18 #include <net/ieee80211_radiotap.h> 19 20 #include "ieee80211_i.h" 21 #include "ieee80211_led.h" 22 #include "wep.h" 23 #include "wpa.h" 24 #include "tkip.h" 25 #include "wme.h" 26 27 /* 28 * monitor mode reception 29 * 30 * This function cleans up the SKB, i.e. it removes all the stuff 31 * only useful for monitoring. 32 */ 33 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 34 struct sk_buff *skb, 35 int rtap_len) 36 { 37 skb_pull(skb, rtap_len); 38 39 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 40 if (likely(skb->len > FCS_LEN)) 41 skb_trim(skb, skb->len - FCS_LEN); 42 else { 43 /* driver bug */ 44 WARN_ON(1); 45 dev_kfree_skb(skb); 46 skb = NULL; 47 } 48 } 49 50 return skb; 51 } 52 53 static inline int should_drop_frame(struct ieee80211_rx_status *status, 54 struct sk_buff *skb, 55 int present_fcs_len, 56 int radiotap_len) 57 { 58 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 59 60 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 61 return 1; 62 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len)) 63 return 1; 64 if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) == 65 cpu_to_le16(IEEE80211_FTYPE_CTL)) 66 return 1; 67 return 0; 68 } 69 70 /* 71 * This function copies a received frame to all monitor interfaces and 72 * returns a cleaned-up SKB that no longer includes the FCS nor the 73 * radiotap header the driver might have added. 74 */ 75 static struct sk_buff * 76 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 77 struct ieee80211_rx_status *status) 78 { 79 struct ieee80211_sub_if_data *sdata; 80 struct ieee80211_rate *rate; 81 int needed_headroom = 0; 82 struct ieee80211_rtap_hdr { 83 struct ieee80211_radiotap_header hdr; 84 u8 flags; 85 u8 rate; 86 __le16 chan_freq; 87 __le16 chan_flags; 88 u8 antsignal; 89 u8 padding_for_rxflags; 90 __le16 rx_flags; 91 } __attribute__ ((packed)) *rthdr; 92 struct sk_buff *skb, *skb2; 93 struct net_device *prev_dev = NULL; 94 int present_fcs_len = 0; 95 int rtap_len = 0; 96 97 /* 98 * First, we may need to make a copy of the skb because 99 * (1) we need to modify it for radiotap (if not present), and 100 * (2) the other RX handlers will modify the skb we got. 101 * 102 * We don't need to, of course, if we aren't going to return 103 * the SKB because it has a bad FCS/PLCP checksum. 104 */ 105 if (status->flag & RX_FLAG_RADIOTAP) 106 rtap_len = ieee80211_get_radiotap_len(origskb->data); 107 else 108 needed_headroom = sizeof(*rthdr); 109 110 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 111 present_fcs_len = FCS_LEN; 112 113 if (!local->monitors) { 114 if (should_drop_frame(status, origskb, present_fcs_len, 115 rtap_len)) { 116 dev_kfree_skb(origskb); 117 return NULL; 118 } 119 120 return remove_monitor_info(local, origskb, rtap_len); 121 } 122 123 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) { 124 /* only need to expand headroom if necessary */ 125 skb = origskb; 126 origskb = NULL; 127 128 /* 129 * This shouldn't trigger often because most devices have an 130 * RX header they pull before we get here, and that should 131 * be big enough for our radiotap information. We should 132 * probably export the length to drivers so that we can have 133 * them allocate enough headroom to start with. 134 */ 135 if (skb_headroom(skb) < needed_headroom && 136 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) { 137 dev_kfree_skb(skb); 138 return NULL; 139 } 140 } else { 141 /* 142 * Need to make a copy and possibly remove radiotap header 143 * and FCS from the original. 144 */ 145 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 146 147 origskb = remove_monitor_info(local, origskb, rtap_len); 148 149 if (!skb) 150 return origskb; 151 } 152 153 /* if necessary, prepend radiotap information */ 154 if (!(status->flag & RX_FLAG_RADIOTAP)) { 155 rthdr = (void *) skb_push(skb, sizeof(*rthdr)); 156 memset(rthdr, 0, sizeof(*rthdr)); 157 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 158 rthdr->hdr.it_present = 159 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 160 (1 << IEEE80211_RADIOTAP_RATE) | 161 (1 << IEEE80211_RADIOTAP_CHANNEL) | 162 (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) | 163 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 164 rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ? 165 IEEE80211_RADIOTAP_F_FCS : 0; 166 167 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */ 168 rthdr->rx_flags = 0; 169 if (status->flag & 170 (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 171 rthdr->rx_flags |= 172 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS); 173 174 rate = ieee80211_get_rate(local, status->phymode, 175 status->rate); 176 if (rate) 177 rthdr->rate = rate->rate / 5; 178 179 rthdr->chan_freq = cpu_to_le16(status->freq); 180 181 if (status->phymode == MODE_IEEE80211A) 182 rthdr->chan_flags = 183 cpu_to_le16(IEEE80211_CHAN_OFDM | 184 IEEE80211_CHAN_5GHZ); 185 else 186 rthdr->chan_flags = 187 cpu_to_le16(IEEE80211_CHAN_DYN | 188 IEEE80211_CHAN_2GHZ); 189 190 rthdr->antsignal = status->ssi; 191 } 192 193 skb_set_mac_header(skb, 0); 194 skb->ip_summed = CHECKSUM_UNNECESSARY; 195 skb->pkt_type = PACKET_OTHERHOST; 196 skb->protocol = htons(ETH_P_802_2); 197 198 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 199 if (!netif_running(sdata->dev)) 200 continue; 201 202 if (sdata->type != IEEE80211_IF_TYPE_MNTR) 203 continue; 204 205 if (prev_dev) { 206 skb2 = skb_clone(skb, GFP_ATOMIC); 207 if (skb2) { 208 skb2->dev = prev_dev; 209 netif_rx(skb2); 210 } 211 } 212 213 prev_dev = sdata->dev; 214 sdata->dev->stats.rx_packets++; 215 sdata->dev->stats.rx_bytes += skb->len; 216 } 217 218 if (prev_dev) { 219 skb->dev = prev_dev; 220 netif_rx(skb); 221 } else 222 dev_kfree_skb(skb); 223 224 return origskb; 225 } 226 227 228 /* pre-rx handlers 229 * 230 * these don't have dev/sdata fields in the rx data 231 * The sta value should also not be used because it may 232 * be NULL even though a STA (in IBSS mode) will be added. 233 */ 234 235 static ieee80211_txrx_result 236 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx) 237 { 238 u8 *data = rx->skb->data; 239 int tid; 240 241 /* does the frame have a qos control field? */ 242 if (WLAN_FC_IS_QOS_DATA(rx->fc)) { 243 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN; 244 /* frame has qos control */ 245 tid = qc[0] & QOS_CONTROL_TID_MASK; 246 } else { 247 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) { 248 /* Separate TID for management frames */ 249 tid = NUM_RX_DATA_QUEUES - 1; 250 } else { 251 /* no qos control present */ 252 tid = 0; /* 802.1d - Best Effort */ 253 } 254 } 255 256 I802_DEBUG_INC(rx->local->wme_rx_queue[tid]); 257 /* only a debug counter, sta might not be assigned properly yet */ 258 if (rx->sta) 259 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]); 260 261 rx->u.rx.queue = tid; 262 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 263 * For now, set skb->priority to 0 for other cases. */ 264 rx->skb->priority = (tid > 7) ? 0 : tid; 265 266 return TXRX_CONTINUE; 267 } 268 269 static ieee80211_txrx_result 270 ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx) 271 { 272 struct ieee80211_local *local = rx->local; 273 struct sk_buff *skb = rx->skb; 274 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 275 u32 load = 0, hdrtime; 276 struct ieee80211_rate *rate; 277 struct ieee80211_hw_mode *mode = local->hw.conf.mode; 278 int i; 279 280 /* Estimate total channel use caused by this frame */ 281 282 if (unlikely(mode->num_rates < 0)) 283 return TXRX_CONTINUE; 284 285 rate = &mode->rates[0]; 286 for (i = 0; i < mode->num_rates; i++) { 287 if (mode->rates[i].val == rx->u.rx.status->rate) { 288 rate = &mode->rates[i]; 289 break; 290 } 291 } 292 293 /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values, 294 * 1 usec = 1/8 * (1080 / 10) = 13.5 */ 295 296 if (mode->mode == MODE_IEEE80211A || 297 (mode->mode == MODE_IEEE80211G && 298 rate->flags & IEEE80211_RATE_ERP)) 299 hdrtime = CHAN_UTIL_HDR_SHORT; 300 else 301 hdrtime = CHAN_UTIL_HDR_LONG; 302 303 load = hdrtime; 304 if (!is_multicast_ether_addr(hdr->addr1)) 305 load += hdrtime; 306 307 load += skb->len * rate->rate_inv; 308 309 /* Divide channel_use by 8 to avoid wrapping around the counter */ 310 load >>= CHAN_UTIL_SHIFT; 311 local->channel_use_raw += load; 312 rx->u.rx.load = load; 313 314 return TXRX_CONTINUE; 315 } 316 317 ieee80211_rx_handler ieee80211_rx_pre_handlers[] = 318 { 319 ieee80211_rx_h_parse_qos, 320 ieee80211_rx_h_load_stats, 321 NULL 322 }; 323 324 /* rx handlers */ 325 326 static ieee80211_txrx_result 327 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx) 328 { 329 if (rx->sta) 330 rx->sta->channel_use_raw += rx->u.rx.load; 331 rx->sdata->channel_use_raw += rx->u.rx.load; 332 return TXRX_CONTINUE; 333 } 334 335 static ieee80211_txrx_result 336 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx) 337 { 338 struct ieee80211_local *local = rx->local; 339 struct sk_buff *skb = rx->skb; 340 341 if (unlikely(local->sta_scanning != 0)) { 342 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status); 343 return TXRX_QUEUED; 344 } 345 346 if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) { 347 /* scanning finished during invoking of handlers */ 348 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 349 return TXRX_DROP; 350 } 351 352 return TXRX_CONTINUE; 353 } 354 355 static ieee80211_txrx_result 356 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx) 357 { 358 struct ieee80211_hdr *hdr; 359 hdr = (struct ieee80211_hdr *) rx->skb->data; 360 361 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 362 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 363 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY && 364 rx->sta->last_seq_ctrl[rx->u.rx.queue] == 365 hdr->seq_ctrl)) { 366 if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) { 367 rx->local->dot11FrameDuplicateCount++; 368 rx->sta->num_duplicates++; 369 } 370 return TXRX_DROP; 371 } else 372 rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl; 373 } 374 375 if (unlikely(rx->skb->len < 16)) { 376 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 377 return TXRX_DROP; 378 } 379 380 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) 381 rx->skb->pkt_type = PACKET_OTHERHOST; 382 else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0) 383 rx->skb->pkt_type = PACKET_HOST; 384 else if (is_multicast_ether_addr(hdr->addr1)) { 385 if (is_broadcast_ether_addr(hdr->addr1)) 386 rx->skb->pkt_type = PACKET_BROADCAST; 387 else 388 rx->skb->pkt_type = PACKET_MULTICAST; 389 } else 390 rx->skb->pkt_type = PACKET_OTHERHOST; 391 392 /* Drop disallowed frame classes based on STA auth/assoc state; 393 * IEEE 802.11, Chap 5.5. 394 * 395 * 80211.o does filtering only based on association state, i.e., it 396 * drops Class 3 frames from not associated stations. hostapd sends 397 * deauth/disassoc frames when needed. In addition, hostapd is 398 * responsible for filtering on both auth and assoc states. 399 */ 400 if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA || 401 ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL && 402 (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) && 403 rx->sdata->type != IEEE80211_IF_TYPE_IBSS && 404 (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) { 405 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) && 406 !(rx->fc & IEEE80211_FCTL_TODS) && 407 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) 408 || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) { 409 /* Drop IBSS frames and frames for other hosts 410 * silently. */ 411 return TXRX_DROP; 412 } 413 414 return TXRX_DROP; 415 } 416 417 return TXRX_CONTINUE; 418 } 419 420 421 static ieee80211_txrx_result 422 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx) 423 { 424 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 425 int keyidx; 426 int hdrlen; 427 ieee80211_txrx_result result = TXRX_DROP; 428 struct ieee80211_key *stakey = NULL; 429 430 /* 431 * Key selection 101 432 * 433 * There are three types of keys: 434 * - GTK (group keys) 435 * - PTK (pairwise keys) 436 * - STK (station-to-station pairwise keys) 437 * 438 * When selecting a key, we have to distinguish between multicast 439 * (including broadcast) and unicast frames, the latter can only 440 * use PTKs and STKs while the former always use GTKs. Unless, of 441 * course, actual WEP keys ("pre-RSNA") are used, then unicast 442 * frames can also use key indizes like GTKs. Hence, if we don't 443 * have a PTK/STK we check the key index for a WEP key. 444 * 445 * Note that in a regular BSS, multicast frames are sent by the 446 * AP only, associated stations unicast the frame to the AP first 447 * which then multicasts it on their behalf. 448 * 449 * There is also a slight problem in IBSS mode: GTKs are negotiated 450 * with each station, that is something we don't currently handle. 451 * The spec seems to expect that one negotiates the same key with 452 * every station but there's no such requirement; VLANs could be 453 * possible. 454 */ 455 456 if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) 457 return TXRX_CONTINUE; 458 459 /* 460 * No point in finding a key and decrypting if the frame is neither 461 * addressed to us nor a multicast frame. 462 */ 463 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) 464 return TXRX_CONTINUE; 465 466 if (rx->sta) 467 stakey = rcu_dereference(rx->sta->key); 468 469 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 470 rx->key = stakey; 471 } else { 472 /* 473 * The device doesn't give us the IV so we won't be 474 * able to look up the key. That's ok though, we 475 * don't need to decrypt the frame, we just won't 476 * be able to keep statistics accurate. 477 * Except for key threshold notifications, should 478 * we somehow allow the driver to tell us which key 479 * the hardware used if this flag is set? 480 */ 481 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && 482 (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) 483 return TXRX_CONTINUE; 484 485 hdrlen = ieee80211_get_hdrlen(rx->fc); 486 487 if (rx->skb->len < 8 + hdrlen) 488 return TXRX_DROP; /* TODO: count this? */ 489 490 /* 491 * no need to call ieee80211_wep_get_keyidx, 492 * it verifies a bunch of things we've done already 493 */ 494 keyidx = rx->skb->data[hdrlen + 3] >> 6; 495 496 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 497 498 /* 499 * RSNA-protected unicast frames should always be sent with 500 * pairwise or station-to-station keys, but for WEP we allow 501 * using a key index as well. 502 */ 503 if (rx->key && rx->key->conf.alg != ALG_WEP && 504 !is_multicast_ether_addr(hdr->addr1)) 505 rx->key = NULL; 506 } 507 508 if (rx->key) { 509 rx->key->tx_rx_count++; 510 /* TODO: add threshold stuff again */ 511 } else { 512 #ifdef CONFIG_MAC80211_DEBUG 513 if (net_ratelimit()) 514 printk(KERN_DEBUG "%s: RX protected frame," 515 " but have no key\n", rx->dev->name); 516 #endif /* CONFIG_MAC80211_DEBUG */ 517 return TXRX_DROP; 518 } 519 520 /* Check for weak IVs if possible */ 521 if (rx->sta && rx->key->conf.alg == ALG_WEP && 522 ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) && 523 (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) || 524 !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) && 525 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 526 rx->sta->wep_weak_iv_count++; 527 528 switch (rx->key->conf.alg) { 529 case ALG_WEP: 530 result = ieee80211_crypto_wep_decrypt(rx); 531 break; 532 case ALG_TKIP: 533 result = ieee80211_crypto_tkip_decrypt(rx); 534 break; 535 case ALG_CCMP: 536 result = ieee80211_crypto_ccmp_decrypt(rx); 537 break; 538 } 539 540 /* either the frame has been decrypted or will be dropped */ 541 rx->u.rx.status->flag |= RX_FLAG_DECRYPTED; 542 543 return result; 544 } 545 546 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta) 547 { 548 struct ieee80211_sub_if_data *sdata; 549 DECLARE_MAC_BUF(mac); 550 551 sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); 552 553 if (sdata->bss) 554 atomic_inc(&sdata->bss->num_sta_ps); 555 sta->flags |= WLAN_STA_PS; 556 sta->pspoll = 0; 557 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 558 printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n", 559 dev->name, print_mac(mac, sta->addr), sta->aid); 560 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 561 } 562 563 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta) 564 { 565 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 566 struct sk_buff *skb; 567 int sent = 0; 568 struct ieee80211_sub_if_data *sdata; 569 struct ieee80211_tx_packet_data *pkt_data; 570 DECLARE_MAC_BUF(mac); 571 572 sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); 573 if (sdata->bss) 574 atomic_dec(&sdata->bss->num_sta_ps); 575 sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM); 576 sta->pspoll = 0; 577 if (!skb_queue_empty(&sta->ps_tx_buf)) { 578 if (local->ops->set_tim) 579 local->ops->set_tim(local_to_hw(local), sta->aid, 0); 580 if (sdata->bss) 581 bss_tim_clear(local, sdata->bss, sta->aid); 582 } 583 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 584 printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n", 585 dev->name, print_mac(mac, sta->addr), sta->aid); 586 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 587 /* Send all buffered frames to the station */ 588 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) { 589 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb; 590 sent++; 591 pkt_data->flags |= IEEE80211_TXPD_REQUEUE; 592 dev_queue_xmit(skb); 593 } 594 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 595 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb; 596 local->total_ps_buffered--; 597 sent++; 598 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 599 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame " 600 "since STA not sleeping anymore\n", dev->name, 601 print_mac(mac, sta->addr), sta->aid); 602 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 603 pkt_data->flags |= IEEE80211_TXPD_REQUEUE; 604 dev_queue_xmit(skb); 605 } 606 607 return sent; 608 } 609 610 static ieee80211_txrx_result 611 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx) 612 { 613 struct sta_info *sta = rx->sta; 614 struct net_device *dev = rx->dev; 615 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 616 617 if (!sta) 618 return TXRX_CONTINUE; 619 620 /* Update last_rx only for IBSS packets which are for the current 621 * BSSID to avoid keeping the current IBSS network alive in cases where 622 * other STAs are using different BSSID. */ 623 if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) { 624 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len); 625 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0) 626 sta->last_rx = jiffies; 627 } else 628 if (!is_multicast_ether_addr(hdr->addr1) || 629 rx->sdata->type == IEEE80211_IF_TYPE_STA) { 630 /* Update last_rx only for unicast frames in order to prevent 631 * the Probe Request frames (the only broadcast frames from a 632 * STA in infrastructure mode) from keeping a connection alive. 633 */ 634 sta->last_rx = jiffies; 635 } 636 637 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) 638 return TXRX_CONTINUE; 639 640 sta->rx_fragments++; 641 sta->rx_bytes += rx->skb->len; 642 sta->last_rssi = rx->u.rx.status->ssi; 643 sta->last_signal = rx->u.rx.status->signal; 644 sta->last_noise = rx->u.rx.status->noise; 645 646 if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) { 647 /* Change STA power saving mode only in the end of a frame 648 * exchange sequence */ 649 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM)) 650 rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta); 651 else if (!(sta->flags & WLAN_STA_PS) && 652 (rx->fc & IEEE80211_FCTL_PM)) 653 ap_sta_ps_start(dev, sta); 654 } 655 656 /* Drop data::nullfunc frames silently, since they are used only to 657 * control station power saving mode. */ 658 if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && 659 (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) { 660 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 661 /* Update counter and free packet here to avoid counting this 662 * as a dropped packed. */ 663 sta->rx_packets++; 664 dev_kfree_skb(rx->skb); 665 return TXRX_QUEUED; 666 } 667 668 return TXRX_CONTINUE; 669 } /* ieee80211_rx_h_sta_process */ 670 671 static inline struct ieee80211_fragment_entry * 672 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 673 unsigned int frag, unsigned int seq, int rx_queue, 674 struct sk_buff **skb) 675 { 676 struct ieee80211_fragment_entry *entry; 677 int idx; 678 679 idx = sdata->fragment_next; 680 entry = &sdata->fragments[sdata->fragment_next++]; 681 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 682 sdata->fragment_next = 0; 683 684 if (!skb_queue_empty(&entry->skb_list)) { 685 #ifdef CONFIG_MAC80211_DEBUG 686 struct ieee80211_hdr *hdr = 687 (struct ieee80211_hdr *) entry->skb_list.next->data; 688 DECLARE_MAC_BUF(mac); 689 DECLARE_MAC_BUF(mac2); 690 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 691 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 692 "addr1=%s addr2=%s\n", 693 sdata->dev->name, idx, 694 jiffies - entry->first_frag_time, entry->seq, 695 entry->last_frag, print_mac(mac, hdr->addr1), 696 print_mac(mac2, hdr->addr2)); 697 #endif /* CONFIG_MAC80211_DEBUG */ 698 __skb_queue_purge(&entry->skb_list); 699 } 700 701 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 702 *skb = NULL; 703 entry->first_frag_time = jiffies; 704 entry->seq = seq; 705 entry->rx_queue = rx_queue; 706 entry->last_frag = frag; 707 entry->ccmp = 0; 708 entry->extra_len = 0; 709 710 return entry; 711 } 712 713 static inline struct ieee80211_fragment_entry * 714 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 715 u16 fc, unsigned int frag, unsigned int seq, 716 int rx_queue, struct ieee80211_hdr *hdr) 717 { 718 struct ieee80211_fragment_entry *entry; 719 int i, idx; 720 721 idx = sdata->fragment_next; 722 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 723 struct ieee80211_hdr *f_hdr; 724 u16 f_fc; 725 726 idx--; 727 if (idx < 0) 728 idx = IEEE80211_FRAGMENT_MAX - 1; 729 730 entry = &sdata->fragments[idx]; 731 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 732 entry->rx_queue != rx_queue || 733 entry->last_frag + 1 != frag) 734 continue; 735 736 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data; 737 f_fc = le16_to_cpu(f_hdr->frame_control); 738 739 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) || 740 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 741 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 742 continue; 743 744 if (entry->first_frag_time + 2 * HZ < jiffies) { 745 __skb_queue_purge(&entry->skb_list); 746 continue; 747 } 748 return entry; 749 } 750 751 return NULL; 752 } 753 754 static ieee80211_txrx_result 755 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx) 756 { 757 struct ieee80211_hdr *hdr; 758 u16 sc; 759 unsigned int frag, seq; 760 struct ieee80211_fragment_entry *entry; 761 struct sk_buff *skb; 762 DECLARE_MAC_BUF(mac); 763 764 hdr = (struct ieee80211_hdr *) rx->skb->data; 765 sc = le16_to_cpu(hdr->seq_ctrl); 766 frag = sc & IEEE80211_SCTL_FRAG; 767 768 if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) || 769 (rx->skb)->len < 24 || 770 is_multicast_ether_addr(hdr->addr1))) { 771 /* not fragmented */ 772 goto out; 773 } 774 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 775 776 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 777 778 if (frag == 0) { 779 /* This is the first fragment of a new frame. */ 780 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 781 rx->u.rx.queue, &(rx->skb)); 782 if (rx->key && rx->key->conf.alg == ALG_CCMP && 783 (rx->fc & IEEE80211_FCTL_PROTECTED)) { 784 /* Store CCMP PN so that we can verify that the next 785 * fragment has a sequential PN value. */ 786 entry->ccmp = 1; 787 memcpy(entry->last_pn, 788 rx->key->u.ccmp.rx_pn[rx->u.rx.queue], 789 CCMP_PN_LEN); 790 } 791 return TXRX_QUEUED; 792 } 793 794 /* This is a fragment for a frame that should already be pending in 795 * fragment cache. Add this fragment to the end of the pending entry. 796 */ 797 entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq, 798 rx->u.rx.queue, hdr); 799 if (!entry) { 800 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 801 return TXRX_DROP; 802 } 803 804 /* Verify that MPDUs within one MSDU have sequential PN values. 805 * (IEEE 802.11i, 8.3.3.4.5) */ 806 if (entry->ccmp) { 807 int i; 808 u8 pn[CCMP_PN_LEN], *rpn; 809 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 810 return TXRX_DROP; 811 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 812 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 813 pn[i]++; 814 if (pn[i]) 815 break; 816 } 817 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue]; 818 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) { 819 if (net_ratelimit()) 820 printk(KERN_DEBUG "%s: defrag: CCMP PN not " 821 "sequential A2=%s" 822 " PN=%02x%02x%02x%02x%02x%02x " 823 "(expected %02x%02x%02x%02x%02x%02x)\n", 824 rx->dev->name, print_mac(mac, hdr->addr2), 825 rpn[0], rpn[1], rpn[2], rpn[3], rpn[4], 826 rpn[5], pn[0], pn[1], pn[2], pn[3], 827 pn[4], pn[5]); 828 return TXRX_DROP; 829 } 830 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 831 } 832 833 skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc)); 834 __skb_queue_tail(&entry->skb_list, rx->skb); 835 entry->last_frag = frag; 836 entry->extra_len += rx->skb->len; 837 if (rx->fc & IEEE80211_FCTL_MOREFRAGS) { 838 rx->skb = NULL; 839 return TXRX_QUEUED; 840 } 841 842 rx->skb = __skb_dequeue(&entry->skb_list); 843 if (skb_tailroom(rx->skb) < entry->extra_len) { 844 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 845 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 846 GFP_ATOMIC))) { 847 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 848 __skb_queue_purge(&entry->skb_list); 849 return TXRX_DROP; 850 } 851 } 852 while ((skb = __skb_dequeue(&entry->skb_list))) { 853 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 854 dev_kfree_skb(skb); 855 } 856 857 /* Complete frame has been reassembled - process it now */ 858 rx->flags |= IEEE80211_TXRXD_FRAGMENTED; 859 860 out: 861 if (rx->sta) 862 rx->sta->rx_packets++; 863 if (is_multicast_ether_addr(hdr->addr1)) 864 rx->local->dot11MulticastReceivedFrameCount++; 865 else 866 ieee80211_led_rx(rx->local); 867 return TXRX_CONTINUE; 868 } 869 870 static ieee80211_txrx_result 871 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx) 872 { 873 struct sk_buff *skb; 874 int no_pending_pkts; 875 DECLARE_MAC_BUF(mac); 876 877 if (likely(!rx->sta || 878 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL || 879 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL || 880 !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))) 881 return TXRX_CONTINUE; 882 883 skb = skb_dequeue(&rx->sta->tx_filtered); 884 if (!skb) { 885 skb = skb_dequeue(&rx->sta->ps_tx_buf); 886 if (skb) 887 rx->local->total_ps_buffered--; 888 } 889 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) && 890 skb_queue_empty(&rx->sta->ps_tx_buf); 891 892 if (skb) { 893 struct ieee80211_hdr *hdr = 894 (struct ieee80211_hdr *) skb->data; 895 896 /* tell TX path to send one frame even though the STA may 897 * still remain is PS mode after this frame exchange */ 898 rx->sta->pspoll = 1; 899 900 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 901 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n", 902 print_mac(mac, rx->sta->addr), rx->sta->aid, 903 skb_queue_len(&rx->sta->ps_tx_buf)); 904 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 905 906 /* Use MoreData flag to indicate whether there are more 907 * buffered frames for this STA */ 908 if (no_pending_pkts) { 909 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 910 rx->sta->flags &= ~WLAN_STA_TIM; 911 } else 912 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 913 914 dev_queue_xmit(skb); 915 916 if (no_pending_pkts) { 917 if (rx->local->ops->set_tim) 918 rx->local->ops->set_tim(local_to_hw(rx->local), 919 rx->sta->aid, 0); 920 if (rx->sdata->bss) 921 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid); 922 } 923 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 924 } else if (!rx->u.rx.sent_ps_buffered) { 925 printk(KERN_DEBUG "%s: STA %s sent PS Poll even " 926 "though there is no buffered frames for it\n", 927 rx->dev->name, print_mac(mac, rx->sta->addr)); 928 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 929 930 } 931 932 /* Free PS Poll skb here instead of returning TXRX_DROP that would 933 * count as an dropped frame. */ 934 dev_kfree_skb(rx->skb); 935 936 return TXRX_QUEUED; 937 } 938 939 static ieee80211_txrx_result 940 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx) 941 { 942 u16 fc = rx->fc; 943 u8 *data = rx->skb->data; 944 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data; 945 946 if (!WLAN_FC_IS_QOS_DATA(fc)) 947 return TXRX_CONTINUE; 948 949 /* remove the qos control field, update frame type and meta-data */ 950 memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2); 951 hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2); 952 /* change frame type to non QOS */ 953 rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA; 954 hdr->frame_control = cpu_to_le16(fc); 955 956 return TXRX_CONTINUE; 957 } 958 959 static ieee80211_txrx_result 960 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx) 961 { 962 if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) && 963 rx->sdata->type != IEEE80211_IF_TYPE_STA && 964 (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) 965 return TXRX_CONTINUE; 966 967 if (unlikely(rx->sdata->ieee802_1x && 968 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && 969 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC && 970 (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) && 971 !ieee80211_is_eapol(rx->skb))) { 972 #ifdef CONFIG_MAC80211_DEBUG 973 struct ieee80211_hdr *hdr = 974 (struct ieee80211_hdr *) rx->skb->data; 975 DECLARE_MAC_BUF(mac); 976 printk(KERN_DEBUG "%s: dropped frame from %s" 977 " (unauthorized port)\n", rx->dev->name, 978 print_mac(mac, hdr->addr2)); 979 #endif /* CONFIG_MAC80211_DEBUG */ 980 return TXRX_DROP; 981 } 982 983 return TXRX_CONTINUE; 984 } 985 986 static ieee80211_txrx_result 987 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx) 988 { 989 /* 990 * Pass through unencrypted frames if the hardware has 991 * decrypted them already. 992 */ 993 if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED) 994 return TXRX_CONTINUE; 995 996 /* Drop unencrypted frames if key is set. */ 997 if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) && 998 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && 999 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC && 1000 (rx->key || rx->sdata->drop_unencrypted) && 1001 (rx->sdata->eapol == 0 || !ieee80211_is_eapol(rx->skb)))) { 1002 if (net_ratelimit()) 1003 printk(KERN_DEBUG "%s: RX non-WEP frame, but expected " 1004 "encryption\n", rx->dev->name); 1005 return TXRX_DROP; 1006 } 1007 return TXRX_CONTINUE; 1008 } 1009 1010 static ieee80211_txrx_result 1011 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx) 1012 { 1013 struct net_device *dev = rx->dev; 1014 struct ieee80211_local *local = rx->local; 1015 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 1016 u16 fc, hdrlen, ethertype; 1017 u8 *payload; 1018 u8 dst[ETH_ALEN]; 1019 u8 src[ETH_ALEN]; 1020 struct sk_buff *skb = rx->skb, *skb2; 1021 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1022 DECLARE_MAC_BUF(mac); 1023 DECLARE_MAC_BUF(mac2); 1024 DECLARE_MAC_BUF(mac3); 1025 DECLARE_MAC_BUF(mac4); 1026 1027 fc = rx->fc; 1028 if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) 1029 return TXRX_CONTINUE; 1030 1031 if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) 1032 return TXRX_DROP; 1033 1034 hdrlen = ieee80211_get_hdrlen(fc); 1035 1036 /* convert IEEE 802.11 header + possible LLC headers into Ethernet 1037 * header 1038 * IEEE 802.11 address fields: 1039 * ToDS FromDS Addr1 Addr2 Addr3 Addr4 1040 * 0 0 DA SA BSSID n/a 1041 * 0 1 DA BSSID SA n/a 1042 * 1 0 BSSID SA DA n/a 1043 * 1 1 RA TA DA SA 1044 */ 1045 1046 switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { 1047 case IEEE80211_FCTL_TODS: 1048 /* BSSID SA DA */ 1049 memcpy(dst, hdr->addr3, ETH_ALEN); 1050 memcpy(src, hdr->addr2, ETH_ALEN); 1051 1052 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP && 1053 sdata->type != IEEE80211_IF_TYPE_VLAN)) { 1054 if (net_ratelimit()) 1055 printk(KERN_DEBUG "%s: dropped ToDS frame " 1056 "(BSSID=%s SA=%s DA=%s)\n", 1057 dev->name, 1058 print_mac(mac, hdr->addr1), 1059 print_mac(mac2, hdr->addr2), 1060 print_mac(mac3, hdr->addr3)); 1061 return TXRX_DROP; 1062 } 1063 break; 1064 case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS): 1065 /* RA TA DA SA */ 1066 memcpy(dst, hdr->addr3, ETH_ALEN); 1067 memcpy(src, hdr->addr4, ETH_ALEN); 1068 1069 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) { 1070 if (net_ratelimit()) 1071 printk(KERN_DEBUG "%s: dropped FromDS&ToDS " 1072 "frame (RA=%s TA=%s DA=%s SA=%s)\n", 1073 rx->dev->name, 1074 print_mac(mac, hdr->addr1), 1075 print_mac(mac2, hdr->addr2), 1076 print_mac(mac3, hdr->addr3), 1077 print_mac(mac4, hdr->addr4)); 1078 return TXRX_DROP; 1079 } 1080 break; 1081 case IEEE80211_FCTL_FROMDS: 1082 /* DA BSSID SA */ 1083 memcpy(dst, hdr->addr1, ETH_ALEN); 1084 memcpy(src, hdr->addr3, ETH_ALEN); 1085 1086 if (sdata->type != IEEE80211_IF_TYPE_STA || 1087 (is_multicast_ether_addr(dst) && 1088 !compare_ether_addr(src, dev->dev_addr))) 1089 return TXRX_DROP; 1090 break; 1091 case 0: 1092 /* DA SA BSSID */ 1093 memcpy(dst, hdr->addr1, ETH_ALEN); 1094 memcpy(src, hdr->addr2, ETH_ALEN); 1095 1096 if (sdata->type != IEEE80211_IF_TYPE_IBSS) { 1097 if (net_ratelimit()) { 1098 printk(KERN_DEBUG "%s: dropped IBSS frame " 1099 "(DA=%s SA=%s BSSID=%s)\n", 1100 dev->name, 1101 print_mac(mac, hdr->addr1), 1102 print_mac(mac2, hdr->addr2), 1103 print_mac(mac3, hdr->addr3)); 1104 } 1105 return TXRX_DROP; 1106 } 1107 break; 1108 } 1109 1110 payload = skb->data + hdrlen; 1111 1112 if (unlikely(skb->len - hdrlen < 8)) { 1113 if (net_ratelimit()) { 1114 printk(KERN_DEBUG "%s: RX too short data frame " 1115 "payload\n", dev->name); 1116 } 1117 return TXRX_DROP; 1118 } 1119 1120 ethertype = (payload[6] << 8) | payload[7]; 1121 1122 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && 1123 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || 1124 compare_ether_addr(payload, bridge_tunnel_header) == 0)) { 1125 /* remove RFC1042 or Bridge-Tunnel encapsulation and 1126 * replace EtherType */ 1127 skb_pull(skb, hdrlen + 6); 1128 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN); 1129 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN); 1130 } else { 1131 struct ethhdr *ehdr; 1132 __be16 len; 1133 skb_pull(skb, hdrlen); 1134 len = htons(skb->len); 1135 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr)); 1136 memcpy(ehdr->h_dest, dst, ETH_ALEN); 1137 memcpy(ehdr->h_source, src, ETH_ALEN); 1138 ehdr->h_proto = len; 1139 } 1140 skb->dev = dev; 1141 1142 skb2 = NULL; 1143 1144 dev->stats.rx_packets++; 1145 dev->stats.rx_bytes += skb->len; 1146 1147 if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP 1148 || sdata->type == IEEE80211_IF_TYPE_VLAN) && 1149 (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) { 1150 if (is_multicast_ether_addr(skb->data)) { 1151 /* send multicast frames both to higher layers in 1152 * local net stack and back to the wireless media */ 1153 skb2 = skb_copy(skb, GFP_ATOMIC); 1154 if (!skb2 && net_ratelimit()) 1155 printk(KERN_DEBUG "%s: failed to clone " 1156 "multicast frame\n", dev->name); 1157 } else { 1158 struct sta_info *dsta; 1159 dsta = sta_info_get(local, skb->data); 1160 if (dsta && !dsta->dev) { 1161 if (net_ratelimit()) 1162 printk(KERN_DEBUG "Station with null " 1163 "dev structure!\n"); 1164 } else if (dsta && dsta->dev == dev) { 1165 /* Destination station is associated to this 1166 * AP, so send the frame directly to it and 1167 * do not pass the frame to local net stack. 1168 */ 1169 skb2 = skb; 1170 skb = NULL; 1171 } 1172 if (dsta) 1173 sta_info_put(dsta); 1174 } 1175 } 1176 1177 if (skb) { 1178 /* deliver to local stack */ 1179 skb->protocol = eth_type_trans(skb, dev); 1180 memset(skb->cb, 0, sizeof(skb->cb)); 1181 netif_rx(skb); 1182 } 1183 1184 if (skb2) { 1185 /* send to wireless media */ 1186 skb2->protocol = __constant_htons(ETH_P_802_3); 1187 skb_set_network_header(skb2, 0); 1188 skb_set_mac_header(skb2, 0); 1189 dev_queue_xmit(skb2); 1190 } 1191 1192 return TXRX_QUEUED; 1193 } 1194 1195 static ieee80211_txrx_result 1196 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx) 1197 { 1198 struct ieee80211_sub_if_data *sdata; 1199 1200 if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) 1201 return TXRX_DROP; 1202 1203 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1204 if ((sdata->type == IEEE80211_IF_TYPE_STA || 1205 sdata->type == IEEE80211_IF_TYPE_IBSS) && 1206 !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)) 1207 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status); 1208 else 1209 return TXRX_DROP; 1210 1211 return TXRX_QUEUED; 1212 } 1213 1214 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers( 1215 struct ieee80211_local *local, 1216 ieee80211_rx_handler *handlers, 1217 struct ieee80211_txrx_data *rx, 1218 struct sta_info *sta) 1219 { 1220 ieee80211_rx_handler *handler; 1221 ieee80211_txrx_result res = TXRX_DROP; 1222 1223 for (handler = handlers; *handler != NULL; handler++) { 1224 res = (*handler)(rx); 1225 1226 switch (res) { 1227 case TXRX_CONTINUE: 1228 continue; 1229 case TXRX_DROP: 1230 I802_DEBUG_INC(local->rx_handlers_drop); 1231 if (sta) 1232 sta->rx_dropped++; 1233 break; 1234 case TXRX_QUEUED: 1235 I802_DEBUG_INC(local->rx_handlers_queued); 1236 break; 1237 } 1238 break; 1239 } 1240 1241 if (res == TXRX_DROP) 1242 dev_kfree_skb(rx->skb); 1243 return res; 1244 } 1245 1246 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local, 1247 ieee80211_rx_handler *handlers, 1248 struct ieee80211_txrx_data *rx, 1249 struct sta_info *sta) 1250 { 1251 if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) == 1252 TXRX_CONTINUE) 1253 dev_kfree_skb(rx->skb); 1254 } 1255 1256 static void ieee80211_rx_michael_mic_report(struct net_device *dev, 1257 struct ieee80211_hdr *hdr, 1258 struct sta_info *sta, 1259 struct ieee80211_txrx_data *rx) 1260 { 1261 int keyidx, hdrlen; 1262 DECLARE_MAC_BUF(mac); 1263 DECLARE_MAC_BUF(mac2); 1264 1265 hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb); 1266 if (rx->skb->len >= hdrlen + 4) 1267 keyidx = rx->skb->data[hdrlen + 3] >> 6; 1268 else 1269 keyidx = -1; 1270 1271 if (net_ratelimit()) 1272 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC " 1273 "failure from %s to %s keyidx=%d\n", 1274 dev->name, print_mac(mac, hdr->addr2), 1275 print_mac(mac2, hdr->addr1), keyidx); 1276 1277 if (!sta) { 1278 /* 1279 * Some hardware seem to generate incorrect Michael MIC 1280 * reports; ignore them to avoid triggering countermeasures. 1281 */ 1282 if (net_ratelimit()) 1283 printk(KERN_DEBUG "%s: ignored spurious Michael MIC " 1284 "error for unknown address %s\n", 1285 dev->name, print_mac(mac, hdr->addr2)); 1286 goto ignore; 1287 } 1288 1289 if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) { 1290 if (net_ratelimit()) 1291 printk(KERN_DEBUG "%s: ignored spurious Michael MIC " 1292 "error for a frame with no PROTECTED flag (src " 1293 "%s)\n", dev->name, print_mac(mac, hdr->addr2)); 1294 goto ignore; 1295 } 1296 1297 if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) { 1298 /* 1299 * APs with pairwise keys should never receive Michael MIC 1300 * errors for non-zero keyidx because these are reserved for 1301 * group keys and only the AP is sending real multicast 1302 * frames in the BSS. 1303 */ 1304 if (net_ratelimit()) 1305 printk(KERN_DEBUG "%s: ignored Michael MIC error for " 1306 "a frame with non-zero keyidx (%d)" 1307 " (src %s)\n", dev->name, keyidx, 1308 print_mac(mac, hdr->addr2)); 1309 goto ignore; 1310 } 1311 1312 if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA && 1313 ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT || 1314 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) { 1315 if (net_ratelimit()) 1316 printk(KERN_DEBUG "%s: ignored spurious Michael MIC " 1317 "error for a frame that cannot be encrypted " 1318 "(fc=0x%04x) (src %s)\n", 1319 dev->name, rx->fc, print_mac(mac, hdr->addr2)); 1320 goto ignore; 1321 } 1322 1323 mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr); 1324 ignore: 1325 dev_kfree_skb(rx->skb); 1326 rx->skb = NULL; 1327 } 1328 1329 ieee80211_rx_handler ieee80211_rx_handlers[] = 1330 { 1331 ieee80211_rx_h_if_stats, 1332 ieee80211_rx_h_passive_scan, 1333 ieee80211_rx_h_check, 1334 ieee80211_rx_h_decrypt, 1335 ieee80211_rx_h_sta_process, 1336 ieee80211_rx_h_defragment, 1337 ieee80211_rx_h_ps_poll, 1338 ieee80211_rx_h_michael_mic_verify, 1339 /* this must be after decryption - so header is counted in MPDU mic 1340 * must be before pae and data, so QOS_DATA format frames 1341 * are not passed to user space by these functions 1342 */ 1343 ieee80211_rx_h_remove_qos_control, 1344 ieee80211_rx_h_802_1x_pae, 1345 ieee80211_rx_h_drop_unencrypted, 1346 ieee80211_rx_h_data, 1347 ieee80211_rx_h_mgmt, 1348 NULL 1349 }; 1350 1351 /* main receive path */ 1352 1353 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 1354 u8 *bssid, struct ieee80211_txrx_data *rx, 1355 struct ieee80211_hdr *hdr) 1356 { 1357 int multicast = is_multicast_ether_addr(hdr->addr1); 1358 1359 switch (sdata->type) { 1360 case IEEE80211_IF_TYPE_STA: 1361 if (!bssid) 1362 return 0; 1363 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { 1364 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) 1365 return 0; 1366 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; 1367 } else if (!multicast && 1368 compare_ether_addr(sdata->dev->dev_addr, 1369 hdr->addr1) != 0) { 1370 if (!(sdata->dev->flags & IFF_PROMISC)) 1371 return 0; 1372 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; 1373 } 1374 break; 1375 case IEEE80211_IF_TYPE_IBSS: 1376 if (!bssid) 1377 return 0; 1378 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { 1379 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) 1380 return 0; 1381 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; 1382 } else if (!multicast && 1383 compare_ether_addr(sdata->dev->dev_addr, 1384 hdr->addr1) != 0) { 1385 if (!(sdata->dev->flags & IFF_PROMISC)) 1386 return 0; 1387 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; 1388 } else if (!rx->sta) 1389 rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb, 1390 bssid, hdr->addr2); 1391 break; 1392 case IEEE80211_IF_TYPE_VLAN: 1393 case IEEE80211_IF_TYPE_AP: 1394 if (!bssid) { 1395 if (compare_ether_addr(sdata->dev->dev_addr, 1396 hdr->addr1)) 1397 return 0; 1398 } else if (!ieee80211_bssid_match(bssid, 1399 sdata->dev->dev_addr)) { 1400 if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) 1401 return 0; 1402 rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH; 1403 } 1404 if (sdata->dev == sdata->local->mdev && 1405 !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) 1406 /* do not receive anything via 1407 * master device when not scanning */ 1408 return 0; 1409 break; 1410 case IEEE80211_IF_TYPE_WDS: 1411 if (bssid || 1412 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) 1413 return 0; 1414 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 1415 return 0; 1416 break; 1417 case IEEE80211_IF_TYPE_MNTR: 1418 /* take everything */ 1419 break; 1420 case IEEE80211_IF_TYPE_INVALID: 1421 /* should never get here */ 1422 WARN_ON(1); 1423 break; 1424 } 1425 1426 return 1; 1427 } 1428 1429 /* 1430 * This is the receive path handler. It is called by a low level driver when an 1431 * 802.11 MPDU is received from the hardware. 1432 */ 1433 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, 1434 struct ieee80211_rx_status *status) 1435 { 1436 struct ieee80211_local *local = hw_to_local(hw); 1437 struct ieee80211_sub_if_data *sdata; 1438 struct sta_info *sta; 1439 struct ieee80211_hdr *hdr; 1440 struct ieee80211_txrx_data rx; 1441 u16 type; 1442 int prepres; 1443 struct ieee80211_sub_if_data *prev = NULL; 1444 struct sk_buff *skb_new; 1445 u8 *bssid; 1446 1447 /* 1448 * key references and virtual interfaces are protected using RCU 1449 * and this requires that we are in a read-side RCU section during 1450 * receive processing 1451 */ 1452 rcu_read_lock(); 1453 1454 /* 1455 * Frames with failed FCS/PLCP checksum are not returned, 1456 * all other frames are returned without radiotap header 1457 * if it was previously present. 1458 * Also, frames with less than 16 bytes are dropped. 1459 */ 1460 skb = ieee80211_rx_monitor(local, skb, status); 1461 if (!skb) { 1462 rcu_read_unlock(); 1463 return; 1464 } 1465 1466 hdr = (struct ieee80211_hdr *) skb->data; 1467 memset(&rx, 0, sizeof(rx)); 1468 rx.skb = skb; 1469 rx.local = local; 1470 1471 rx.u.rx.status = status; 1472 rx.fc = le16_to_cpu(hdr->frame_control); 1473 type = rx.fc & IEEE80211_FCTL_FTYPE; 1474 1475 if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT) 1476 local->dot11ReceivedFragmentCount++; 1477 1478 sta = rx.sta = sta_info_get(local, hdr->addr2); 1479 if (sta) { 1480 rx.dev = rx.sta->dev; 1481 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev); 1482 } 1483 1484 if ((status->flag & RX_FLAG_MMIC_ERROR)) { 1485 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx); 1486 goto end; 1487 } 1488 1489 if (unlikely(local->sta_scanning)) 1490 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN; 1491 1492 if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx, 1493 sta) != TXRX_CONTINUE) 1494 goto end; 1495 skb = rx.skb; 1496 1497 if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) && 1498 !atomic_read(&local->iff_promiscs) && 1499 !is_multicast_ether_addr(hdr->addr1)) { 1500 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH; 1501 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx, 1502 rx.sta); 1503 sta_info_put(sta); 1504 rcu_read_unlock(); 1505 return; 1506 } 1507 1508 bssid = ieee80211_get_bssid(hdr, skb->len); 1509 1510 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 1511 if (!netif_running(sdata->dev)) 1512 continue; 1513 1514 if (sdata->type == IEEE80211_IF_TYPE_MNTR) 1515 continue; 1516 1517 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH; 1518 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr); 1519 /* prepare_for_handlers can change sta */ 1520 sta = rx.sta; 1521 1522 if (!prepres) 1523 continue; 1524 1525 /* 1526 * frame is destined for this interface, but if it's not 1527 * also for the previous one we handle that after the 1528 * loop to avoid copying the SKB once too much 1529 */ 1530 1531 if (!prev) { 1532 prev = sdata; 1533 continue; 1534 } 1535 1536 /* 1537 * frame was destined for the previous interface 1538 * so invoke RX handlers for it 1539 */ 1540 1541 skb_new = skb_copy(skb, GFP_ATOMIC); 1542 if (!skb_new) { 1543 if (net_ratelimit()) 1544 printk(KERN_DEBUG "%s: failed to copy " 1545 "multicast frame for %s", 1546 wiphy_name(local->hw.wiphy), 1547 prev->dev->name); 1548 continue; 1549 } 1550 rx.skb = skb_new; 1551 rx.dev = prev->dev; 1552 rx.sdata = prev; 1553 ieee80211_invoke_rx_handlers(local, local->rx_handlers, 1554 &rx, sta); 1555 prev = sdata; 1556 } 1557 if (prev) { 1558 rx.skb = skb; 1559 rx.dev = prev->dev; 1560 rx.sdata = prev; 1561 ieee80211_invoke_rx_handlers(local, local->rx_handlers, 1562 &rx, sta); 1563 } else 1564 dev_kfree_skb(skb); 1565 1566 end: 1567 rcu_read_unlock(); 1568 1569 if (sta) 1570 sta_info_put(sta); 1571 } 1572 EXPORT_SYMBOL(__ieee80211_rx); 1573 1574 /* This is a version of the rx handler that can be called from hard irq 1575 * context. Post the skb on the queue and schedule the tasklet */ 1576 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, 1577 struct ieee80211_rx_status *status) 1578 { 1579 struct ieee80211_local *local = hw_to_local(hw); 1580 1581 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 1582 1583 skb->dev = local->mdev; 1584 /* copy status into skb->cb for use by tasklet */ 1585 memcpy(skb->cb, status, sizeof(*status)); 1586 skb->pkt_type = IEEE80211_RX_MSG; 1587 skb_queue_tail(&local->skb_queue, skb); 1588 tasklet_schedule(&local->tasklet); 1589 } 1590 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 1591