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/jiffies.h> 13 #include <linux/kernel.h> 14 #include <linux/skbuff.h> 15 #include <linux/netdevice.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rcupdate.h> 18 #include <net/mac80211.h> 19 #include <net/ieee80211_radiotap.h> 20 21 #include "ieee80211_i.h" 22 #include "led.h" 23 #include "mesh.h" 24 #include "wep.h" 25 #include "wpa.h" 26 #include "tkip.h" 27 #include "wme.h" 28 29 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 30 struct tid_ampdu_rx *tid_agg_rx, 31 struct sk_buff *skb, u16 mpdu_seq_num, 32 int bar_req); 33 /* 34 * monitor mode reception 35 * 36 * This function cleans up the SKB, i.e. it removes all the stuff 37 * only useful for monitoring. 38 */ 39 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 40 struct sk_buff *skb, 41 int rtap_len) 42 { 43 skb_pull(skb, rtap_len); 44 45 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 46 if (likely(skb->len > FCS_LEN)) 47 skb_trim(skb, skb->len - FCS_LEN); 48 else { 49 /* driver bug */ 50 WARN_ON(1); 51 dev_kfree_skb(skb); 52 skb = NULL; 53 } 54 } 55 56 return skb; 57 } 58 59 static inline int should_drop_frame(struct ieee80211_rx_status *status, 60 struct sk_buff *skb, 61 int present_fcs_len, 62 int radiotap_len) 63 { 64 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 65 66 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 67 return 1; 68 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len)) 69 return 1; 70 if (ieee80211_is_ctl(hdr->frame_control) && 71 !ieee80211_is_pspoll(hdr->frame_control) && 72 !ieee80211_is_back_req(hdr->frame_control)) 73 return 1; 74 return 0; 75 } 76 77 static int 78 ieee80211_rx_radiotap_len(struct ieee80211_local *local, 79 struct ieee80211_rx_status *status) 80 { 81 int len; 82 83 /* always present fields */ 84 len = sizeof(struct ieee80211_radiotap_header) + 9; 85 86 if (status->flag & RX_FLAG_TSFT) 87 len += 8; 88 if (local->hw.flags & IEEE80211_HW_SIGNAL_DB || 89 local->hw.flags & IEEE80211_HW_SIGNAL_DBM) 90 len += 1; 91 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) 92 len += 1; 93 94 if (len & 1) /* padding for RX_FLAGS if necessary */ 95 len++; 96 97 /* make sure radiotap starts at a naturally aligned address */ 98 if (len % 8) 99 len = roundup(len, 8); 100 101 return len; 102 } 103 104 /** 105 * ieee80211_add_rx_radiotap_header - add radiotap header 106 * 107 * add a radiotap header containing all the fields which the hardware provided. 108 */ 109 static void 110 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 111 struct sk_buff *skb, 112 struct ieee80211_rx_status *status, 113 struct ieee80211_rate *rate, 114 int rtap_len) 115 { 116 struct ieee80211_radiotap_header *rthdr; 117 unsigned char *pos; 118 119 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 120 memset(rthdr, 0, rtap_len); 121 122 /* radiotap header, set always present flags */ 123 rthdr->it_present = 124 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 125 (1 << IEEE80211_RADIOTAP_RATE) | 126 (1 << IEEE80211_RADIOTAP_CHANNEL) | 127 (1 << IEEE80211_RADIOTAP_ANTENNA) | 128 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 129 rthdr->it_len = cpu_to_le16(rtap_len); 130 131 pos = (unsigned char *)(rthdr+1); 132 133 /* the order of the following fields is important */ 134 135 /* IEEE80211_RADIOTAP_TSFT */ 136 if (status->flag & RX_FLAG_TSFT) { 137 *(__le64 *)pos = cpu_to_le64(status->mactime); 138 rthdr->it_present |= 139 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 140 pos += 8; 141 } 142 143 /* IEEE80211_RADIOTAP_FLAGS */ 144 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 145 *pos |= IEEE80211_RADIOTAP_F_FCS; 146 pos++; 147 148 /* IEEE80211_RADIOTAP_RATE */ 149 *pos = rate->bitrate / 5; 150 pos++; 151 152 /* IEEE80211_RADIOTAP_CHANNEL */ 153 *(__le16 *)pos = cpu_to_le16(status->freq); 154 pos += 2; 155 if (status->band == IEEE80211_BAND_5GHZ) 156 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | 157 IEEE80211_CHAN_5GHZ); 158 else 159 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_DYN | 160 IEEE80211_CHAN_2GHZ); 161 pos += 2; 162 163 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ 164 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { 165 *pos = status->signal; 166 rthdr->it_present |= 167 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); 168 pos++; 169 } 170 171 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */ 172 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) { 173 *pos = status->noise; 174 rthdr->it_present |= 175 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE); 176 pos++; 177 } 178 179 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ 180 181 /* IEEE80211_RADIOTAP_ANTENNA */ 182 *pos = status->antenna; 183 pos++; 184 185 /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */ 186 if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) { 187 *pos = status->signal; 188 rthdr->it_present |= 189 cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL); 190 pos++; 191 } 192 193 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ 194 195 /* IEEE80211_RADIOTAP_RX_FLAGS */ 196 /* ensure 2 byte alignment for the 2 byte field as required */ 197 if ((pos - (unsigned char *)rthdr) & 1) 198 pos++; 199 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */ 200 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 201 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS); 202 pos += 2; 203 } 204 205 /* 206 * This function copies a received frame to all monitor interfaces and 207 * returns a cleaned-up SKB that no longer includes the FCS nor the 208 * radiotap header the driver might have added. 209 */ 210 static struct sk_buff * 211 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 212 struct ieee80211_rx_status *status, 213 struct ieee80211_rate *rate) 214 { 215 struct ieee80211_sub_if_data *sdata; 216 int needed_headroom = 0; 217 struct sk_buff *skb, *skb2; 218 struct net_device *prev_dev = NULL; 219 int present_fcs_len = 0; 220 int rtap_len = 0; 221 222 /* 223 * First, we may need to make a copy of the skb because 224 * (1) we need to modify it for radiotap (if not present), and 225 * (2) the other RX handlers will modify the skb we got. 226 * 227 * We don't need to, of course, if we aren't going to return 228 * the SKB because it has a bad FCS/PLCP checksum. 229 */ 230 if (status->flag & RX_FLAG_RADIOTAP) 231 rtap_len = ieee80211_get_radiotap_len(origskb->data); 232 else 233 /* room for the radiotap header based on driver features */ 234 needed_headroom = ieee80211_rx_radiotap_len(local, status); 235 236 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 237 present_fcs_len = FCS_LEN; 238 239 if (!local->monitors) { 240 if (should_drop_frame(status, origskb, present_fcs_len, 241 rtap_len)) { 242 dev_kfree_skb(origskb); 243 return NULL; 244 } 245 246 return remove_monitor_info(local, origskb, rtap_len); 247 } 248 249 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) { 250 /* only need to expand headroom if necessary */ 251 skb = origskb; 252 origskb = NULL; 253 254 /* 255 * This shouldn't trigger often because most devices have an 256 * RX header they pull before we get here, and that should 257 * be big enough for our radiotap information. We should 258 * probably export the length to drivers so that we can have 259 * them allocate enough headroom to start with. 260 */ 261 if (skb_headroom(skb) < needed_headroom && 262 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) { 263 dev_kfree_skb(skb); 264 return NULL; 265 } 266 } else { 267 /* 268 * Need to make a copy and possibly remove radiotap header 269 * and FCS from the original. 270 */ 271 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 272 273 origskb = remove_monitor_info(local, origskb, rtap_len); 274 275 if (!skb) 276 return origskb; 277 } 278 279 /* if necessary, prepend radiotap information */ 280 if (!(status->flag & RX_FLAG_RADIOTAP)) 281 ieee80211_add_rx_radiotap_header(local, skb, status, rate, 282 needed_headroom); 283 284 skb_reset_mac_header(skb); 285 skb->ip_summed = CHECKSUM_UNNECESSARY; 286 skb->pkt_type = PACKET_OTHERHOST; 287 skb->protocol = htons(ETH_P_802_2); 288 289 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 290 if (!netif_running(sdata->dev)) 291 continue; 292 293 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR) 294 continue; 295 296 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 297 continue; 298 299 if (prev_dev) { 300 skb2 = skb_clone(skb, GFP_ATOMIC); 301 if (skb2) { 302 skb2->dev = prev_dev; 303 netif_rx(skb2); 304 } 305 } 306 307 prev_dev = sdata->dev; 308 sdata->dev->stats.rx_packets++; 309 sdata->dev->stats.rx_bytes += skb->len; 310 } 311 312 if (prev_dev) { 313 skb->dev = prev_dev; 314 netif_rx(skb); 315 } else 316 dev_kfree_skb(skb); 317 318 return origskb; 319 } 320 321 322 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 323 { 324 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 325 int tid; 326 327 /* does the frame have a qos control field? */ 328 if (ieee80211_is_data_qos(hdr->frame_control)) { 329 u8 *qc = ieee80211_get_qos_ctl(hdr); 330 /* frame has qos control */ 331 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 332 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 333 rx->flags |= IEEE80211_RX_AMSDU; 334 else 335 rx->flags &= ~IEEE80211_RX_AMSDU; 336 } else { 337 /* 338 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 339 * 340 * Sequence numbers for management frames, QoS data 341 * frames with a broadcast/multicast address in the 342 * Address 1 field, and all non-QoS data frames sent 343 * by QoS STAs are assigned using an additional single 344 * modulo-4096 counter, [...] 345 * 346 * We also use that counter for non-QoS STAs. 347 */ 348 tid = NUM_RX_DATA_QUEUES - 1; 349 } 350 351 rx->queue = tid; 352 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 353 * For now, set skb->priority to 0 for other cases. */ 354 rx->skb->priority = (tid > 7) ? 0 : tid; 355 } 356 357 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx) 358 { 359 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT 360 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 361 int hdrlen; 362 363 if (!ieee80211_is_data_present(hdr->frame_control)) 364 return; 365 366 /* 367 * Drivers are required to align the payload data in a way that 368 * guarantees that the contained IP header is aligned to a four- 369 * byte boundary. In the case of regular frames, this simply means 370 * aligning the payload to a four-byte boundary (because either 371 * the IP header is directly contained, or IV/RFC1042 headers that 372 * have a length divisible by four are in front of it. 373 * 374 * With A-MSDU frames, however, the payload data address must 375 * yield two modulo four because there are 14-byte 802.3 headers 376 * within the A-MSDU frames that push the IP header further back 377 * to a multiple of four again. Thankfully, the specs were sane 378 * enough this time around to require padding each A-MSDU subframe 379 * to a length that is a multiple of four. 380 * 381 * Padding like atheros hardware adds which is inbetween the 802.11 382 * header and the payload is not supported, the driver is required 383 * to move the 802.11 header further back in that case. 384 */ 385 hdrlen = ieee80211_hdrlen(hdr->frame_control); 386 if (rx->flags & IEEE80211_RX_AMSDU) 387 hdrlen += ETH_HLEN; 388 WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3); 389 #endif 390 } 391 392 393 /* rx handlers */ 394 395 static ieee80211_rx_result debug_noinline 396 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 397 { 398 struct ieee80211_local *local = rx->local; 399 struct sk_buff *skb = rx->skb; 400 401 if (unlikely(local->sta_hw_scanning)) 402 return ieee80211_sta_rx_scan(rx->dev, skb, rx->status); 403 404 if (unlikely(local->sta_sw_scanning)) { 405 /* drop all the other packets during a software scan anyway */ 406 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->status) 407 != RX_QUEUED) 408 dev_kfree_skb(skb); 409 return RX_QUEUED; 410 } 411 412 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { 413 /* scanning finished during invoking of handlers */ 414 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 415 return RX_DROP_UNUSABLE; 416 } 417 418 return RX_CONTINUE; 419 } 420 421 static ieee80211_rx_result 422 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 423 { 424 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 425 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 426 427 if (ieee80211_is_data(hdr->frame_control)) { 428 if (!ieee80211_has_a4(hdr->frame_control)) 429 return RX_DROP_MONITOR; 430 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0) 431 return RX_DROP_MONITOR; 432 } 433 434 /* If there is not an established peer link and this is not a peer link 435 * establisment frame, beacon or probe, drop the frame. 436 */ 437 438 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 439 struct ieee80211_mgmt *mgmt; 440 441 if (!ieee80211_is_mgmt(hdr->frame_control)) 442 return RX_DROP_MONITOR; 443 444 if (ieee80211_is_action(hdr->frame_control)) { 445 mgmt = (struct ieee80211_mgmt *)hdr; 446 if (mgmt->u.action.category != PLINK_CATEGORY) 447 return RX_DROP_MONITOR; 448 return RX_CONTINUE; 449 } 450 451 if (ieee80211_is_probe_req(hdr->frame_control) || 452 ieee80211_is_probe_resp(hdr->frame_control) || 453 ieee80211_is_beacon(hdr->frame_control)) 454 return RX_CONTINUE; 455 456 return RX_DROP_MONITOR; 457 458 } 459 460 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 461 462 if (ieee80211_is_data(hdr->frame_control) && 463 is_multicast_ether_addr(hdr->addr1) && 464 mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->dev)) 465 return RX_DROP_MONITOR; 466 #undef msh_h_get 467 468 return RX_CONTINUE; 469 } 470 471 472 static ieee80211_rx_result debug_noinline 473 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 474 { 475 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 476 477 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 478 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 479 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 480 rx->sta->last_seq_ctrl[rx->queue] == 481 hdr->seq_ctrl)) { 482 if (rx->flags & IEEE80211_RX_RA_MATCH) { 483 rx->local->dot11FrameDuplicateCount++; 484 rx->sta->num_duplicates++; 485 } 486 return RX_DROP_MONITOR; 487 } else 488 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 489 } 490 491 if (unlikely(rx->skb->len < 16)) { 492 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 493 return RX_DROP_MONITOR; 494 } 495 496 /* Drop disallowed frame classes based on STA auth/assoc state; 497 * IEEE 802.11, Chap 5.5. 498 * 499 * 80211.o does filtering only based on association state, i.e., it 500 * drops Class 3 frames from not associated stations. hostapd sends 501 * deauth/disassoc frames when needed. In addition, hostapd is 502 * responsible for filtering on both auth and assoc states. 503 */ 504 505 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 506 return ieee80211_rx_mesh_check(rx); 507 508 if (unlikely((ieee80211_is_data(hdr->frame_control) || 509 ieee80211_is_pspoll(hdr->frame_control)) && 510 rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS && 511 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 512 if ((!ieee80211_has_fromds(hdr->frame_control) && 513 !ieee80211_has_tods(hdr->frame_control) && 514 ieee80211_is_data(hdr->frame_control)) || 515 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 516 /* Drop IBSS frames and frames for other hosts 517 * silently. */ 518 return RX_DROP_MONITOR; 519 } 520 521 return RX_DROP_MONITOR; 522 } 523 524 return RX_CONTINUE; 525 } 526 527 528 static ieee80211_rx_result debug_noinline 529 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 530 { 531 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 532 int keyidx; 533 int hdrlen; 534 ieee80211_rx_result result = RX_DROP_UNUSABLE; 535 struct ieee80211_key *stakey = NULL; 536 537 /* 538 * Key selection 101 539 * 540 * There are three types of keys: 541 * - GTK (group keys) 542 * - PTK (pairwise keys) 543 * - STK (station-to-station pairwise keys) 544 * 545 * When selecting a key, we have to distinguish between multicast 546 * (including broadcast) and unicast frames, the latter can only 547 * use PTKs and STKs while the former always use GTKs. Unless, of 548 * course, actual WEP keys ("pre-RSNA") are used, then unicast 549 * frames can also use key indizes like GTKs. Hence, if we don't 550 * have a PTK/STK we check the key index for a WEP key. 551 * 552 * Note that in a regular BSS, multicast frames are sent by the 553 * AP only, associated stations unicast the frame to the AP first 554 * which then multicasts it on their behalf. 555 * 556 * There is also a slight problem in IBSS mode: GTKs are negotiated 557 * with each station, that is something we don't currently handle. 558 * The spec seems to expect that one negotiates the same key with 559 * every station but there's no such requirement; VLANs could be 560 * possible. 561 */ 562 563 if (!ieee80211_has_protected(hdr->frame_control)) 564 return RX_CONTINUE; 565 566 /* 567 * No point in finding a key and decrypting if the frame is neither 568 * addressed to us nor a multicast frame. 569 */ 570 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 571 return RX_CONTINUE; 572 573 if (rx->sta) 574 stakey = rcu_dereference(rx->sta->key); 575 576 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 577 rx->key = stakey; 578 } else { 579 /* 580 * The device doesn't give us the IV so we won't be 581 * able to look up the key. That's ok though, we 582 * don't need to decrypt the frame, we just won't 583 * be able to keep statistics accurate. 584 * Except for key threshold notifications, should 585 * we somehow allow the driver to tell us which key 586 * the hardware used if this flag is set? 587 */ 588 if ((rx->status->flag & RX_FLAG_DECRYPTED) && 589 (rx->status->flag & RX_FLAG_IV_STRIPPED)) 590 return RX_CONTINUE; 591 592 hdrlen = ieee80211_hdrlen(hdr->frame_control); 593 594 if (rx->skb->len < 8 + hdrlen) 595 return RX_DROP_UNUSABLE; /* TODO: count this? */ 596 597 /* 598 * no need to call ieee80211_wep_get_keyidx, 599 * it verifies a bunch of things we've done already 600 */ 601 keyidx = rx->skb->data[hdrlen + 3] >> 6; 602 603 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 604 605 /* 606 * RSNA-protected unicast frames should always be sent with 607 * pairwise or station-to-station keys, but for WEP we allow 608 * using a key index as well. 609 */ 610 if (rx->key && rx->key->conf.alg != ALG_WEP && 611 !is_multicast_ether_addr(hdr->addr1)) 612 rx->key = NULL; 613 } 614 615 if (rx->key) { 616 rx->key->tx_rx_count++; 617 /* TODO: add threshold stuff again */ 618 } else { 619 return RX_DROP_MONITOR; 620 } 621 622 /* Check for weak IVs if possible */ 623 if (rx->sta && rx->key->conf.alg == ALG_WEP && 624 ieee80211_is_data(hdr->frame_control) && 625 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) || 626 !(rx->status->flag & RX_FLAG_DECRYPTED)) && 627 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 628 rx->sta->wep_weak_iv_count++; 629 630 switch (rx->key->conf.alg) { 631 case ALG_WEP: 632 result = ieee80211_crypto_wep_decrypt(rx); 633 break; 634 case ALG_TKIP: 635 result = ieee80211_crypto_tkip_decrypt(rx); 636 break; 637 case ALG_CCMP: 638 result = ieee80211_crypto_ccmp_decrypt(rx); 639 break; 640 } 641 642 /* either the frame has been decrypted or will be dropped */ 643 rx->status->flag |= RX_FLAG_DECRYPTED; 644 645 return result; 646 } 647 648 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta) 649 { 650 struct ieee80211_sub_if_data *sdata; 651 DECLARE_MAC_BUF(mac); 652 653 sdata = sta->sdata; 654 655 atomic_inc(&sdata->bss->num_sta_ps); 656 set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL); 657 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 658 printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n", 659 dev->name, print_mac(mac, sta->addr), sta->aid); 660 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 661 } 662 663 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta) 664 { 665 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 666 struct sk_buff *skb; 667 int sent = 0; 668 struct ieee80211_sub_if_data *sdata; 669 struct ieee80211_tx_info *info; 670 DECLARE_MAC_BUF(mac); 671 672 sdata = sta->sdata; 673 674 atomic_dec(&sdata->bss->num_sta_ps); 675 676 clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL); 677 678 if (!skb_queue_empty(&sta->ps_tx_buf)) 679 sta_info_clear_tim_bit(sta); 680 681 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 682 printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n", 683 dev->name, print_mac(mac, sta->addr), sta->aid); 684 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 685 686 /* Send all buffered frames to the station */ 687 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) { 688 info = IEEE80211_SKB_CB(skb); 689 sent++; 690 info->flags |= IEEE80211_TX_CTL_REQUEUE; 691 dev_queue_xmit(skb); 692 } 693 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 694 info = IEEE80211_SKB_CB(skb); 695 local->total_ps_buffered--; 696 sent++; 697 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 698 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame " 699 "since STA not sleeping anymore\n", dev->name, 700 print_mac(mac, sta->addr), sta->aid); 701 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 702 info->flags |= IEEE80211_TX_CTL_REQUEUE; 703 dev_queue_xmit(skb); 704 } 705 706 return sent; 707 } 708 709 static ieee80211_rx_result debug_noinline 710 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 711 { 712 struct sta_info *sta = rx->sta; 713 struct net_device *dev = rx->dev; 714 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 715 716 if (!sta) 717 return RX_CONTINUE; 718 719 /* Update last_rx only for IBSS packets which are for the current 720 * BSSID to avoid keeping the current IBSS network alive in cases where 721 * other STAs are using different BSSID. */ 722 if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) { 723 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 724 IEEE80211_IF_TYPE_IBSS); 725 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0) 726 sta->last_rx = jiffies; 727 } else 728 if (!is_multicast_ether_addr(hdr->addr1) || 729 rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) { 730 /* Update last_rx only for unicast frames in order to prevent 731 * the Probe Request frames (the only broadcast frames from a 732 * STA in infrastructure mode) from keeping a connection alive. 733 * Mesh beacons will update last_rx when if they are found to 734 * match the current local configuration when processed. 735 */ 736 sta->last_rx = jiffies; 737 } 738 739 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 740 return RX_CONTINUE; 741 742 sta->rx_fragments++; 743 sta->rx_bytes += rx->skb->len; 744 sta->last_signal = rx->status->signal; 745 sta->last_qual = rx->status->qual; 746 sta->last_noise = rx->status->noise; 747 748 if (!ieee80211_has_morefrags(hdr->frame_control) && 749 (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP || 750 rx->sdata->vif.type == IEEE80211_IF_TYPE_VLAN)) { 751 /* Change STA power saving mode only in the end of a frame 752 * exchange sequence */ 753 if (test_sta_flags(sta, WLAN_STA_PS) && 754 !ieee80211_has_pm(hdr->frame_control)) 755 rx->sent_ps_buffered += ap_sta_ps_end(dev, sta); 756 else if (!test_sta_flags(sta, WLAN_STA_PS) && 757 ieee80211_has_pm(hdr->frame_control)) 758 ap_sta_ps_start(dev, sta); 759 } 760 761 /* Drop data::nullfunc frames silently, since they are used only to 762 * control station power saving mode. */ 763 if (ieee80211_is_nullfunc(hdr->frame_control)) { 764 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 765 /* Update counter and free packet here to avoid counting this 766 * as a dropped packed. */ 767 sta->rx_packets++; 768 dev_kfree_skb(rx->skb); 769 return RX_QUEUED; 770 } 771 772 return RX_CONTINUE; 773 } /* ieee80211_rx_h_sta_process */ 774 775 static inline struct ieee80211_fragment_entry * 776 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 777 unsigned int frag, unsigned int seq, int rx_queue, 778 struct sk_buff **skb) 779 { 780 struct ieee80211_fragment_entry *entry; 781 int idx; 782 783 idx = sdata->fragment_next; 784 entry = &sdata->fragments[sdata->fragment_next++]; 785 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 786 sdata->fragment_next = 0; 787 788 if (!skb_queue_empty(&entry->skb_list)) { 789 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 790 struct ieee80211_hdr *hdr = 791 (struct ieee80211_hdr *) entry->skb_list.next->data; 792 DECLARE_MAC_BUF(mac); 793 DECLARE_MAC_BUF(mac2); 794 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 795 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 796 "addr1=%s addr2=%s\n", 797 sdata->dev->name, idx, 798 jiffies - entry->first_frag_time, entry->seq, 799 entry->last_frag, print_mac(mac, hdr->addr1), 800 print_mac(mac2, hdr->addr2)); 801 #endif 802 __skb_queue_purge(&entry->skb_list); 803 } 804 805 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 806 *skb = NULL; 807 entry->first_frag_time = jiffies; 808 entry->seq = seq; 809 entry->rx_queue = rx_queue; 810 entry->last_frag = frag; 811 entry->ccmp = 0; 812 entry->extra_len = 0; 813 814 return entry; 815 } 816 817 static inline struct ieee80211_fragment_entry * 818 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 819 u16 fc, unsigned int frag, unsigned int seq, 820 int rx_queue, struct ieee80211_hdr *hdr) 821 { 822 struct ieee80211_fragment_entry *entry; 823 int i, idx; 824 825 idx = sdata->fragment_next; 826 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 827 struct ieee80211_hdr *f_hdr; 828 u16 f_fc; 829 830 idx--; 831 if (idx < 0) 832 idx = IEEE80211_FRAGMENT_MAX - 1; 833 834 entry = &sdata->fragments[idx]; 835 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 836 entry->rx_queue != rx_queue || 837 entry->last_frag + 1 != frag) 838 continue; 839 840 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data; 841 f_fc = le16_to_cpu(f_hdr->frame_control); 842 843 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) || 844 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 845 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 846 continue; 847 848 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 849 __skb_queue_purge(&entry->skb_list); 850 continue; 851 } 852 return entry; 853 } 854 855 return NULL; 856 } 857 858 static ieee80211_rx_result debug_noinline 859 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 860 { 861 struct ieee80211_hdr *hdr; 862 u16 sc; 863 unsigned int frag, seq; 864 struct ieee80211_fragment_entry *entry; 865 struct sk_buff *skb; 866 DECLARE_MAC_BUF(mac); 867 868 hdr = (struct ieee80211_hdr *) rx->skb->data; 869 sc = le16_to_cpu(hdr->seq_ctrl); 870 frag = sc & IEEE80211_SCTL_FRAG; 871 872 if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) || 873 (rx->skb)->len < 24 || 874 is_multicast_ether_addr(hdr->addr1))) { 875 /* not fragmented */ 876 goto out; 877 } 878 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 879 880 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 881 882 if (frag == 0) { 883 /* This is the first fragment of a new frame. */ 884 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 885 rx->queue, &(rx->skb)); 886 if (rx->key && rx->key->conf.alg == ALG_CCMP && 887 (rx->fc & IEEE80211_FCTL_PROTECTED)) { 888 /* Store CCMP PN so that we can verify that the next 889 * fragment has a sequential PN value. */ 890 entry->ccmp = 1; 891 memcpy(entry->last_pn, 892 rx->key->u.ccmp.rx_pn[rx->queue], 893 CCMP_PN_LEN); 894 } 895 return RX_QUEUED; 896 } 897 898 /* This is a fragment for a frame that should already be pending in 899 * fragment cache. Add this fragment to the end of the pending entry. 900 */ 901 entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq, 902 rx->queue, hdr); 903 if (!entry) { 904 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 905 return RX_DROP_MONITOR; 906 } 907 908 /* Verify that MPDUs within one MSDU have sequential PN values. 909 * (IEEE 802.11i, 8.3.3.4.5) */ 910 if (entry->ccmp) { 911 int i; 912 u8 pn[CCMP_PN_LEN], *rpn; 913 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 914 return RX_DROP_UNUSABLE; 915 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 916 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 917 pn[i]++; 918 if (pn[i]) 919 break; 920 } 921 rpn = rx->key->u.ccmp.rx_pn[rx->queue]; 922 if (memcmp(pn, rpn, CCMP_PN_LEN)) 923 return RX_DROP_UNUSABLE; 924 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 925 } 926 927 skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc)); 928 __skb_queue_tail(&entry->skb_list, rx->skb); 929 entry->last_frag = frag; 930 entry->extra_len += rx->skb->len; 931 if (rx->fc & IEEE80211_FCTL_MOREFRAGS) { 932 rx->skb = NULL; 933 return RX_QUEUED; 934 } 935 936 rx->skb = __skb_dequeue(&entry->skb_list); 937 if (skb_tailroom(rx->skb) < entry->extra_len) { 938 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 939 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 940 GFP_ATOMIC))) { 941 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 942 __skb_queue_purge(&entry->skb_list); 943 return RX_DROP_UNUSABLE; 944 } 945 } 946 while ((skb = __skb_dequeue(&entry->skb_list))) { 947 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 948 dev_kfree_skb(skb); 949 } 950 951 /* Complete frame has been reassembled - process it now */ 952 rx->flags |= IEEE80211_RX_FRAGMENTED; 953 954 out: 955 if (rx->sta) 956 rx->sta->rx_packets++; 957 if (is_multicast_ether_addr(hdr->addr1)) 958 rx->local->dot11MulticastReceivedFrameCount++; 959 else 960 ieee80211_led_rx(rx->local); 961 return RX_CONTINUE; 962 } 963 964 static ieee80211_rx_result debug_noinline 965 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 966 { 967 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 968 struct sk_buff *skb; 969 int no_pending_pkts; 970 DECLARE_MAC_BUF(mac); 971 972 if (likely(!rx->sta || 973 (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL || 974 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL || 975 !(rx->flags & IEEE80211_RX_RA_MATCH))) 976 return RX_CONTINUE; 977 978 if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) && 979 (sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) 980 return RX_DROP_UNUSABLE; 981 982 skb = skb_dequeue(&rx->sta->tx_filtered); 983 if (!skb) { 984 skb = skb_dequeue(&rx->sta->ps_tx_buf); 985 if (skb) 986 rx->local->total_ps_buffered--; 987 } 988 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) && 989 skb_queue_empty(&rx->sta->ps_tx_buf); 990 991 if (skb) { 992 struct ieee80211_hdr *hdr = 993 (struct ieee80211_hdr *) skb->data; 994 995 /* 996 * Tell TX path to send one frame even though the STA may 997 * still remain is PS mode after this frame exchange. 998 */ 999 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1000 1001 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1002 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n", 1003 print_mac(mac, rx->sta->addr), rx->sta->aid, 1004 skb_queue_len(&rx->sta->ps_tx_buf)); 1005 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1006 1007 /* Use MoreData flag to indicate whether there are more 1008 * buffered frames for this STA */ 1009 if (no_pending_pkts) 1010 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 1011 else 1012 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 1013 1014 dev_queue_xmit(skb); 1015 1016 if (no_pending_pkts) 1017 sta_info_clear_tim_bit(rx->sta); 1018 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1019 } else if (!rx->sent_ps_buffered) { 1020 /* 1021 * FIXME: This can be the result of a race condition between 1022 * us expiring a frame and the station polling for it. 1023 * Should we send it a null-func frame indicating we 1024 * have nothing buffered for it? 1025 */ 1026 printk(KERN_DEBUG "%s: STA %s sent PS Poll even " 1027 "though there are no buffered frames for it\n", 1028 rx->dev->name, print_mac(mac, rx->sta->addr)); 1029 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1030 } 1031 1032 /* Free PS Poll skb here instead of returning RX_DROP that would 1033 * count as an dropped frame. */ 1034 dev_kfree_skb(rx->skb); 1035 1036 return RX_QUEUED; 1037 } 1038 1039 static ieee80211_rx_result debug_noinline 1040 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1041 { 1042 u8 *data = rx->skb->data; 1043 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1044 1045 if (!ieee80211_is_data_qos(hdr->frame_control)) 1046 return RX_CONTINUE; 1047 1048 /* remove the qos control field, update frame type and meta-data */ 1049 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1050 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1051 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1052 /* change frame type to non QOS */ 1053 rx->fc &= ~IEEE80211_STYPE_QOS_DATA; 1054 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1055 1056 return RX_CONTINUE; 1057 } 1058 1059 static int 1060 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1061 { 1062 if (unlikely(!rx->sta || 1063 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1064 return -EACCES; 1065 1066 return 0; 1067 } 1068 1069 static int 1070 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx) 1071 { 1072 /* 1073 * Pass through unencrypted frames if the hardware has 1074 * decrypted them already. 1075 */ 1076 if (rx->status->flag & RX_FLAG_DECRYPTED) 1077 return 0; 1078 1079 /* Drop unencrypted frames if key is set. */ 1080 if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) && 1081 (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && 1082 (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC && 1083 (rx->key || rx->sdata->drop_unencrypted))) 1084 return -EACCES; 1085 1086 return 0; 1087 } 1088 1089 static int 1090 ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1091 { 1092 struct net_device *dev = rx->dev; 1093 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 1094 u16 fc, hdrlen, ethertype; 1095 u8 *payload; 1096 u8 dst[ETH_ALEN]; 1097 u8 src[ETH_ALEN] __aligned(2); 1098 struct sk_buff *skb = rx->skb; 1099 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1100 DECLARE_MAC_BUF(mac); 1101 DECLARE_MAC_BUF(mac2); 1102 DECLARE_MAC_BUF(mac3); 1103 DECLARE_MAC_BUF(mac4); 1104 1105 fc = rx->fc; 1106 1107 if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) 1108 return -1; 1109 1110 hdrlen = ieee80211_get_hdrlen(fc); 1111 1112 if (ieee80211_vif_is_mesh(&sdata->vif)) { 1113 int meshhdrlen = ieee80211_get_mesh_hdrlen( 1114 (struct ieee80211s_hdr *) (skb->data + hdrlen)); 1115 /* Copy on cb: 1116 * - mesh header: to be used for mesh forwarding 1117 * decision. It will also be used as mesh header template at 1118 * tx.c:ieee80211_subif_start_xmit() if interface 1119 * type is mesh and skb->pkt_type == PACKET_OTHERHOST 1120 * - ta: to be used if a RERR needs to be sent. 1121 */ 1122 memcpy(skb->cb, skb->data + hdrlen, meshhdrlen); 1123 memcpy(MESH_PREQ(skb), hdr->addr2, ETH_ALEN); 1124 hdrlen += meshhdrlen; 1125 } 1126 1127 /* convert IEEE 802.11 header + possible LLC headers into Ethernet 1128 * header 1129 * IEEE 802.11 address fields: 1130 * ToDS FromDS Addr1 Addr2 Addr3 Addr4 1131 * 0 0 DA SA BSSID n/a 1132 * 0 1 DA BSSID SA n/a 1133 * 1 0 BSSID SA DA n/a 1134 * 1 1 RA TA DA SA 1135 */ 1136 1137 switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { 1138 case IEEE80211_FCTL_TODS: 1139 /* BSSID SA DA */ 1140 memcpy(dst, hdr->addr3, ETH_ALEN); 1141 memcpy(src, hdr->addr2, ETH_ALEN); 1142 1143 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP && 1144 sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) 1145 return -1; 1146 break; 1147 case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS): 1148 /* RA TA DA SA */ 1149 memcpy(dst, hdr->addr3, ETH_ALEN); 1150 memcpy(src, hdr->addr4, ETH_ALEN); 1151 1152 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS && 1153 sdata->vif.type != IEEE80211_IF_TYPE_MESH_POINT)) 1154 return -1; 1155 break; 1156 case IEEE80211_FCTL_FROMDS: 1157 /* DA BSSID SA */ 1158 memcpy(dst, hdr->addr1, ETH_ALEN); 1159 memcpy(src, hdr->addr3, ETH_ALEN); 1160 1161 if (sdata->vif.type != IEEE80211_IF_TYPE_STA || 1162 (is_multicast_ether_addr(dst) && 1163 !compare_ether_addr(src, dev->dev_addr))) 1164 return -1; 1165 break; 1166 case 0: 1167 /* DA SA BSSID */ 1168 memcpy(dst, hdr->addr1, ETH_ALEN); 1169 memcpy(src, hdr->addr2, ETH_ALEN); 1170 1171 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) 1172 return -1; 1173 break; 1174 } 1175 1176 if (unlikely(skb->len - hdrlen < 8)) 1177 return -1; 1178 1179 payload = skb->data + hdrlen; 1180 ethertype = (payload[6] << 8) | payload[7]; 1181 1182 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && 1183 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || 1184 compare_ether_addr(payload, bridge_tunnel_header) == 0)) { 1185 /* remove RFC1042 or Bridge-Tunnel encapsulation and 1186 * replace EtherType */ 1187 skb_pull(skb, hdrlen + 6); 1188 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN); 1189 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN); 1190 } else { 1191 struct ethhdr *ehdr; 1192 __be16 len; 1193 1194 skb_pull(skb, hdrlen); 1195 len = htons(skb->len); 1196 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr)); 1197 memcpy(ehdr->h_dest, dst, ETH_ALEN); 1198 memcpy(ehdr->h_source, src, ETH_ALEN); 1199 ehdr->h_proto = len; 1200 } 1201 return 0; 1202 } 1203 1204 /* 1205 * requires that rx->skb is a frame with ethernet header 1206 */ 1207 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx) 1208 { 1209 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1210 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1211 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1212 1213 /* 1214 * Allow EAPOL frames to us/the PAE group address regardless 1215 * of whether the frame was encrypted or not. 1216 */ 1217 if (ehdr->h_proto == htons(ETH_P_PAE) && 1218 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 || 1219 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1220 return true; 1221 1222 if (ieee80211_802_1x_port_control(rx) || 1223 ieee80211_drop_unencrypted(rx)) 1224 return false; 1225 1226 return true; 1227 } 1228 1229 /* 1230 * requires that rx->skb is a frame with ethernet header 1231 */ 1232 static void 1233 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1234 { 1235 struct net_device *dev = rx->dev; 1236 struct ieee80211_local *local = rx->local; 1237 struct sk_buff *skb, *xmit_skb; 1238 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1239 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1240 struct sta_info *dsta; 1241 1242 skb = rx->skb; 1243 xmit_skb = NULL; 1244 1245 if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP || 1246 sdata->vif.type == IEEE80211_IF_TYPE_VLAN) && 1247 (rx->flags & IEEE80211_RX_RA_MATCH)) { 1248 if (is_multicast_ether_addr(ehdr->h_dest)) { 1249 /* 1250 * send multicast frames both to higher layers in 1251 * local net stack and back to the wireless medium 1252 */ 1253 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1254 if (!xmit_skb && net_ratelimit()) 1255 printk(KERN_DEBUG "%s: failed to clone " 1256 "multicast frame\n", dev->name); 1257 } else { 1258 dsta = sta_info_get(local, skb->data); 1259 if (dsta && dsta->sdata->dev == dev) { 1260 /* 1261 * The destination station is associated to 1262 * this AP (in this VLAN), so send the frame 1263 * directly to it and do not pass it to local 1264 * net stack. 1265 */ 1266 xmit_skb = skb; 1267 skb = NULL; 1268 } 1269 } 1270 } 1271 1272 /* Mesh forwarding */ 1273 if (ieee80211_vif_is_mesh(&sdata->vif)) { 1274 u8 *mesh_ttl = &((struct ieee80211s_hdr *)skb->cb)->ttl; 1275 (*mesh_ttl)--; 1276 1277 if (is_multicast_ether_addr(skb->data)) { 1278 if (*mesh_ttl > 0) { 1279 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1280 if (xmit_skb) 1281 xmit_skb->pkt_type = PACKET_OTHERHOST; 1282 else if (net_ratelimit()) 1283 printk(KERN_DEBUG "%s: failed to clone " 1284 "multicast frame\n", dev->name); 1285 } else 1286 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta, 1287 dropped_frames_ttl); 1288 } else if (skb->pkt_type != PACKET_OTHERHOST && 1289 compare_ether_addr(dev->dev_addr, skb->data) != 0) { 1290 if (*mesh_ttl == 0) { 1291 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta, 1292 dropped_frames_ttl); 1293 dev_kfree_skb(skb); 1294 skb = NULL; 1295 } else { 1296 xmit_skb = skb; 1297 xmit_skb->pkt_type = PACKET_OTHERHOST; 1298 if (!(dev->flags & IFF_PROMISC)) 1299 skb = NULL; 1300 } 1301 } 1302 } 1303 1304 if (skb) { 1305 /* deliver to local stack */ 1306 skb->protocol = eth_type_trans(skb, dev); 1307 memset(skb->cb, 0, sizeof(skb->cb)); 1308 netif_rx(skb); 1309 } 1310 1311 if (xmit_skb) { 1312 /* send to wireless media */ 1313 xmit_skb->protocol = htons(ETH_P_802_3); 1314 skb_reset_network_header(xmit_skb); 1315 skb_reset_mac_header(xmit_skb); 1316 dev_queue_xmit(xmit_skb); 1317 } 1318 } 1319 1320 static ieee80211_rx_result debug_noinline 1321 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1322 { 1323 struct net_device *dev = rx->dev; 1324 struct ieee80211_local *local = rx->local; 1325 u16 fc, ethertype; 1326 u8 *payload; 1327 struct sk_buff *skb = rx->skb, *frame = NULL; 1328 const struct ethhdr *eth; 1329 int remaining, err; 1330 u8 dst[ETH_ALEN]; 1331 u8 src[ETH_ALEN]; 1332 DECLARE_MAC_BUF(mac); 1333 1334 fc = rx->fc; 1335 if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) 1336 return RX_CONTINUE; 1337 1338 if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) 1339 return RX_DROP_MONITOR; 1340 1341 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1342 return RX_CONTINUE; 1343 1344 err = ieee80211_data_to_8023(rx); 1345 if (unlikely(err)) 1346 return RX_DROP_UNUSABLE; 1347 1348 skb->dev = dev; 1349 1350 dev->stats.rx_packets++; 1351 dev->stats.rx_bytes += skb->len; 1352 1353 /* skip the wrapping header */ 1354 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr)); 1355 if (!eth) 1356 return RX_DROP_UNUSABLE; 1357 1358 while (skb != frame) { 1359 u8 padding; 1360 __be16 len = eth->h_proto; 1361 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len); 1362 1363 remaining = skb->len; 1364 memcpy(dst, eth->h_dest, ETH_ALEN); 1365 memcpy(src, eth->h_source, ETH_ALEN); 1366 1367 padding = ((4 - subframe_len) & 0x3); 1368 /* the last MSDU has no padding */ 1369 if (subframe_len > remaining) 1370 return RX_DROP_UNUSABLE; 1371 1372 skb_pull(skb, sizeof(struct ethhdr)); 1373 /* if last subframe reuse skb */ 1374 if (remaining <= subframe_len + padding) 1375 frame = skb; 1376 else { 1377 frame = dev_alloc_skb(local->hw.extra_tx_headroom + 1378 subframe_len); 1379 1380 if (frame == NULL) 1381 return RX_DROP_UNUSABLE; 1382 1383 skb_reserve(frame, local->hw.extra_tx_headroom + 1384 sizeof(struct ethhdr)); 1385 memcpy(skb_put(frame, ntohs(len)), skb->data, 1386 ntohs(len)); 1387 1388 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) + 1389 padding); 1390 if (!eth) { 1391 dev_kfree_skb(frame); 1392 return RX_DROP_UNUSABLE; 1393 } 1394 } 1395 1396 skb_reset_network_header(frame); 1397 frame->dev = dev; 1398 frame->priority = skb->priority; 1399 rx->skb = frame; 1400 1401 payload = frame->data; 1402 ethertype = (payload[6] << 8) | payload[7]; 1403 1404 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && 1405 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || 1406 compare_ether_addr(payload, 1407 bridge_tunnel_header) == 0)) { 1408 /* remove RFC1042 or Bridge-Tunnel 1409 * encapsulation and replace EtherType */ 1410 skb_pull(frame, 6); 1411 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1412 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1413 } else { 1414 memcpy(skb_push(frame, sizeof(__be16)), 1415 &len, sizeof(__be16)); 1416 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1417 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1418 } 1419 1420 if (!ieee80211_frame_allowed(rx)) { 1421 if (skb == frame) /* last frame */ 1422 return RX_DROP_UNUSABLE; 1423 dev_kfree_skb(frame); 1424 continue; 1425 } 1426 1427 ieee80211_deliver_skb(rx); 1428 } 1429 1430 return RX_QUEUED; 1431 } 1432 1433 static ieee80211_rx_result debug_noinline 1434 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1435 { 1436 struct net_device *dev = rx->dev; 1437 u16 fc; 1438 int err; 1439 1440 fc = rx->fc; 1441 if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) 1442 return RX_CONTINUE; 1443 1444 if (unlikely(!WLAN_FC_DATA_PRESENT(fc))) 1445 return RX_DROP_MONITOR; 1446 1447 err = ieee80211_data_to_8023(rx); 1448 if (unlikely(err)) 1449 return RX_DROP_UNUSABLE; 1450 1451 if (!ieee80211_frame_allowed(rx)) 1452 return RX_DROP_MONITOR; 1453 1454 rx->skb->dev = dev; 1455 1456 dev->stats.rx_packets++; 1457 dev->stats.rx_bytes += rx->skb->len; 1458 1459 ieee80211_deliver_skb(rx); 1460 1461 return RX_QUEUED; 1462 } 1463 1464 static ieee80211_rx_result debug_noinline 1465 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx) 1466 { 1467 struct ieee80211_local *local = rx->local; 1468 struct ieee80211_hw *hw = &local->hw; 1469 struct sk_buff *skb = rx->skb; 1470 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1471 struct tid_ampdu_rx *tid_agg_rx; 1472 u16 start_seq_num; 1473 u16 tid; 1474 1475 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1476 return RX_CONTINUE; 1477 1478 if (ieee80211_is_back_req(bar->frame_control)) { 1479 if (!rx->sta) 1480 return RX_CONTINUE; 1481 tid = le16_to_cpu(bar->control) >> 12; 1482 if (rx->sta->ampdu_mlme.tid_state_rx[tid] 1483 != HT_AGG_STATE_OPERATIONAL) 1484 return RX_CONTINUE; 1485 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; 1486 1487 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4; 1488 1489 /* reset session timer */ 1490 if (tid_agg_rx->timeout) { 1491 unsigned long expires = 1492 jiffies + (tid_agg_rx->timeout / 1000) * HZ; 1493 mod_timer(&tid_agg_rx->session_timer, expires); 1494 } 1495 1496 /* manage reordering buffer according to requested */ 1497 /* sequence number */ 1498 rcu_read_lock(); 1499 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, 1500 start_seq_num, 1); 1501 rcu_read_unlock(); 1502 return RX_DROP_UNUSABLE; 1503 } 1504 1505 return RX_CONTINUE; 1506 } 1507 1508 static ieee80211_rx_result debug_noinline 1509 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 1510 { 1511 struct ieee80211_sub_if_data *sdata; 1512 1513 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1514 return RX_DROP_MONITOR; 1515 1516 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1517 if ((sdata->vif.type == IEEE80211_IF_TYPE_STA || 1518 sdata->vif.type == IEEE80211_IF_TYPE_IBSS || 1519 sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) && 1520 !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)) 1521 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->status); 1522 else 1523 return RX_DROP_MONITOR; 1524 1525 return RX_QUEUED; 1526 } 1527 1528 static void ieee80211_rx_michael_mic_report(struct net_device *dev, 1529 struct ieee80211_hdr *hdr, 1530 struct ieee80211_rx_data *rx) 1531 { 1532 int keyidx; 1533 unsigned int hdrlen; 1534 DECLARE_MAC_BUF(mac); 1535 DECLARE_MAC_BUF(mac2); 1536 1537 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1538 if (rx->skb->len >= hdrlen + 4) 1539 keyidx = rx->skb->data[hdrlen + 3] >> 6; 1540 else 1541 keyidx = -1; 1542 1543 if (!rx->sta) { 1544 /* 1545 * Some hardware seem to generate incorrect Michael MIC 1546 * reports; ignore them to avoid triggering countermeasures. 1547 */ 1548 goto ignore; 1549 } 1550 1551 if (!ieee80211_has_protected(hdr->frame_control)) 1552 goto ignore; 1553 1554 if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) { 1555 /* 1556 * APs with pairwise keys should never receive Michael MIC 1557 * errors for non-zero keyidx because these are reserved for 1558 * group keys and only the AP is sending real multicast 1559 * frames in the BSS. 1560 */ 1561 goto ignore; 1562 } 1563 1564 if (!ieee80211_is_data(hdr->frame_control) && 1565 !ieee80211_is_auth(hdr->frame_control)) 1566 goto ignore; 1567 1568 mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr); 1569 ignore: 1570 dev_kfree_skb(rx->skb); 1571 rx->skb = NULL; 1572 } 1573 1574 /* TODO: use IEEE80211_RX_FRAGMENTED */ 1575 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx) 1576 { 1577 struct ieee80211_sub_if_data *sdata; 1578 struct ieee80211_local *local = rx->local; 1579 struct ieee80211_rtap_hdr { 1580 struct ieee80211_radiotap_header hdr; 1581 u8 flags; 1582 u8 rate; 1583 __le16 chan_freq; 1584 __le16 chan_flags; 1585 } __attribute__ ((packed)) *rthdr; 1586 struct sk_buff *skb = rx->skb, *skb2; 1587 struct net_device *prev_dev = NULL; 1588 struct ieee80211_rx_status *status = rx->status; 1589 1590 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED) 1591 goto out_free_skb; 1592 1593 if (skb_headroom(skb) < sizeof(*rthdr) && 1594 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 1595 goto out_free_skb; 1596 1597 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 1598 memset(rthdr, 0, sizeof(*rthdr)); 1599 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 1600 rthdr->hdr.it_present = 1601 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 1602 (1 << IEEE80211_RADIOTAP_RATE) | 1603 (1 << IEEE80211_RADIOTAP_CHANNEL)); 1604 1605 rthdr->rate = rx->rate->bitrate / 5; 1606 rthdr->chan_freq = cpu_to_le16(status->freq); 1607 1608 if (status->band == IEEE80211_BAND_5GHZ) 1609 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 1610 IEEE80211_CHAN_5GHZ); 1611 else 1612 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 1613 IEEE80211_CHAN_2GHZ); 1614 1615 skb_set_mac_header(skb, 0); 1616 skb->ip_summed = CHECKSUM_UNNECESSARY; 1617 skb->pkt_type = PACKET_OTHERHOST; 1618 skb->protocol = htons(ETH_P_802_2); 1619 1620 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 1621 if (!netif_running(sdata->dev)) 1622 continue; 1623 1624 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR || 1625 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 1626 continue; 1627 1628 if (prev_dev) { 1629 skb2 = skb_clone(skb, GFP_ATOMIC); 1630 if (skb2) { 1631 skb2->dev = prev_dev; 1632 netif_rx(skb2); 1633 } 1634 } 1635 1636 prev_dev = sdata->dev; 1637 sdata->dev->stats.rx_packets++; 1638 sdata->dev->stats.rx_bytes += skb->len; 1639 } 1640 1641 if (prev_dev) { 1642 skb->dev = prev_dev; 1643 netif_rx(skb); 1644 skb = NULL; 1645 } else 1646 goto out_free_skb; 1647 1648 rx->flags |= IEEE80211_RX_CMNTR_REPORTED; 1649 return; 1650 1651 out_free_skb: 1652 dev_kfree_skb(skb); 1653 } 1654 1655 1656 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 1657 struct ieee80211_rx_data *rx, 1658 struct sk_buff *skb) 1659 { 1660 ieee80211_rx_result res = RX_DROP_MONITOR; 1661 1662 rx->skb = skb; 1663 rx->sdata = sdata; 1664 rx->dev = sdata->dev; 1665 1666 #define CALL_RXH(rxh) \ 1667 res = rxh(rx); \ 1668 if (res != RX_CONTINUE) \ 1669 goto rxh_done; 1670 1671 CALL_RXH(ieee80211_rx_h_passive_scan) 1672 CALL_RXH(ieee80211_rx_h_check) 1673 CALL_RXH(ieee80211_rx_h_decrypt) 1674 CALL_RXH(ieee80211_rx_h_sta_process) 1675 CALL_RXH(ieee80211_rx_h_defragment) 1676 CALL_RXH(ieee80211_rx_h_ps_poll) 1677 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 1678 /* must be after MMIC verify so header is counted in MPDU mic */ 1679 CALL_RXH(ieee80211_rx_h_remove_qos_control) 1680 CALL_RXH(ieee80211_rx_h_amsdu) 1681 CALL_RXH(ieee80211_rx_h_data) 1682 CALL_RXH(ieee80211_rx_h_ctrl) 1683 CALL_RXH(ieee80211_rx_h_mgmt) 1684 1685 #undef CALL_RXH 1686 1687 rxh_done: 1688 switch (res) { 1689 case RX_DROP_MONITOR: 1690 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 1691 if (rx->sta) 1692 rx->sta->rx_dropped++; 1693 /* fall through */ 1694 case RX_CONTINUE: 1695 ieee80211_rx_cooked_monitor(rx); 1696 break; 1697 case RX_DROP_UNUSABLE: 1698 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 1699 if (rx->sta) 1700 rx->sta->rx_dropped++; 1701 dev_kfree_skb(rx->skb); 1702 break; 1703 case RX_QUEUED: 1704 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 1705 break; 1706 } 1707 } 1708 1709 /* main receive path */ 1710 1711 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 1712 u8 *bssid, struct ieee80211_rx_data *rx, 1713 struct ieee80211_hdr *hdr) 1714 { 1715 int multicast = is_multicast_ether_addr(hdr->addr1); 1716 1717 switch (sdata->vif.type) { 1718 case IEEE80211_IF_TYPE_STA: 1719 if (!bssid) 1720 return 0; 1721 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { 1722 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 1723 return 0; 1724 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1725 } else if (!multicast && 1726 compare_ether_addr(sdata->dev->dev_addr, 1727 hdr->addr1) != 0) { 1728 if (!(sdata->dev->flags & IFF_PROMISC)) 1729 return 0; 1730 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1731 } 1732 break; 1733 case IEEE80211_IF_TYPE_IBSS: 1734 if (!bssid) 1735 return 0; 1736 if (ieee80211_is_beacon(hdr->frame_control)) { 1737 if (!rx->sta) 1738 rx->sta = ieee80211_ibss_add_sta(sdata->dev, 1739 rx->skb, bssid, hdr->addr2, 1740 BIT(rx->status->rate_idx)); 1741 return 1; 1742 } 1743 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) { 1744 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 1745 return 0; 1746 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1747 } else if (!multicast && 1748 compare_ether_addr(sdata->dev->dev_addr, 1749 hdr->addr1) != 0) { 1750 if (!(sdata->dev->flags & IFF_PROMISC)) 1751 return 0; 1752 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1753 } else if (!rx->sta) 1754 rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb, 1755 bssid, hdr->addr2, 1756 BIT(rx->status->rate_idx)); 1757 break; 1758 case IEEE80211_IF_TYPE_MESH_POINT: 1759 if (!multicast && 1760 compare_ether_addr(sdata->dev->dev_addr, 1761 hdr->addr1) != 0) { 1762 if (!(sdata->dev->flags & IFF_PROMISC)) 1763 return 0; 1764 1765 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1766 } 1767 break; 1768 case IEEE80211_IF_TYPE_VLAN: 1769 case IEEE80211_IF_TYPE_AP: 1770 if (!bssid) { 1771 if (compare_ether_addr(sdata->dev->dev_addr, 1772 hdr->addr1)) 1773 return 0; 1774 } else if (!ieee80211_bssid_match(bssid, 1775 sdata->dev->dev_addr)) { 1776 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 1777 return 0; 1778 rx->flags &= ~IEEE80211_RX_RA_MATCH; 1779 } 1780 break; 1781 case IEEE80211_IF_TYPE_WDS: 1782 if (bssid || !ieee80211_is_data(hdr->frame_control)) 1783 return 0; 1784 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 1785 return 0; 1786 break; 1787 case IEEE80211_IF_TYPE_MNTR: 1788 /* take everything */ 1789 break; 1790 case IEEE80211_IF_TYPE_INVALID: 1791 /* should never get here */ 1792 WARN_ON(1); 1793 break; 1794 } 1795 1796 return 1; 1797 } 1798 1799 /* 1800 * This is the actual Rx frames handler. as it blongs to Rx path it must 1801 * be called with rcu_read_lock protection. 1802 */ 1803 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 1804 struct sk_buff *skb, 1805 struct ieee80211_rx_status *status, 1806 struct ieee80211_rate *rate) 1807 { 1808 struct ieee80211_local *local = hw_to_local(hw); 1809 struct ieee80211_sub_if_data *sdata; 1810 struct ieee80211_hdr *hdr; 1811 struct ieee80211_rx_data rx; 1812 u16 type; 1813 int prepares; 1814 struct ieee80211_sub_if_data *prev = NULL; 1815 struct sk_buff *skb_new; 1816 u8 *bssid; 1817 1818 hdr = (struct ieee80211_hdr *) skb->data; 1819 memset(&rx, 0, sizeof(rx)); 1820 rx.skb = skb; 1821 rx.local = local; 1822 1823 rx.status = status; 1824 rx.rate = rate; 1825 rx.fc = le16_to_cpu(hdr->frame_control); 1826 type = rx.fc & IEEE80211_FCTL_FTYPE; 1827 1828 if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT) 1829 local->dot11ReceivedFragmentCount++; 1830 1831 rx.sta = sta_info_get(local, hdr->addr2); 1832 if (rx.sta) { 1833 rx.sdata = rx.sta->sdata; 1834 rx.dev = rx.sta->sdata->dev; 1835 } 1836 1837 if ((status->flag & RX_FLAG_MMIC_ERROR)) { 1838 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx); 1839 return; 1840 } 1841 1842 if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning)) 1843 rx.flags |= IEEE80211_RX_IN_SCAN; 1844 1845 ieee80211_parse_qos(&rx); 1846 ieee80211_verify_ip_alignment(&rx); 1847 1848 skb = rx.skb; 1849 1850 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 1851 if (!netif_running(sdata->dev)) 1852 continue; 1853 1854 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR) 1855 continue; 1856 1857 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 1858 rx.flags |= IEEE80211_RX_RA_MATCH; 1859 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr); 1860 1861 if (!prepares) 1862 continue; 1863 1864 /* 1865 * frame is destined for this interface, but if it's not 1866 * also for the previous one we handle that after the 1867 * loop to avoid copying the SKB once too much 1868 */ 1869 1870 if (!prev) { 1871 prev = sdata; 1872 continue; 1873 } 1874 1875 /* 1876 * frame was destined for the previous interface 1877 * so invoke RX handlers for it 1878 */ 1879 1880 skb_new = skb_copy(skb, GFP_ATOMIC); 1881 if (!skb_new) { 1882 if (net_ratelimit()) 1883 printk(KERN_DEBUG "%s: failed to copy " 1884 "multicast frame for %s\n", 1885 wiphy_name(local->hw.wiphy), 1886 prev->dev->name); 1887 continue; 1888 } 1889 rx.fc = le16_to_cpu(hdr->frame_control); 1890 ieee80211_invoke_rx_handlers(prev, &rx, skb_new); 1891 prev = sdata; 1892 } 1893 if (prev) { 1894 rx.fc = le16_to_cpu(hdr->frame_control); 1895 ieee80211_invoke_rx_handlers(prev, &rx, skb); 1896 } else 1897 dev_kfree_skb(skb); 1898 } 1899 1900 #define SEQ_MODULO 0x1000 1901 #define SEQ_MASK 0xfff 1902 1903 static inline int seq_less(u16 sq1, u16 sq2) 1904 { 1905 return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1)); 1906 } 1907 1908 static inline u16 seq_inc(u16 sq) 1909 { 1910 return ((sq + 1) & SEQ_MASK); 1911 } 1912 1913 static inline u16 seq_sub(u16 sq1, u16 sq2) 1914 { 1915 return ((sq1 - sq2) & SEQ_MASK); 1916 } 1917 1918 1919 /* 1920 * As it function blongs to Rx path it must be called with 1921 * the proper rcu_read_lock protection for its flow. 1922 */ 1923 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 1924 struct tid_ampdu_rx *tid_agg_rx, 1925 struct sk_buff *skb, u16 mpdu_seq_num, 1926 int bar_req) 1927 { 1928 struct ieee80211_local *local = hw_to_local(hw); 1929 struct ieee80211_rx_status status; 1930 u16 head_seq_num, buf_size; 1931 int index; 1932 struct ieee80211_supported_band *sband; 1933 struct ieee80211_rate *rate; 1934 1935 buf_size = tid_agg_rx->buf_size; 1936 head_seq_num = tid_agg_rx->head_seq_num; 1937 1938 /* frame with out of date sequence number */ 1939 if (seq_less(mpdu_seq_num, head_seq_num)) { 1940 dev_kfree_skb(skb); 1941 return 1; 1942 } 1943 1944 /* if frame sequence number exceeds our buffering window size or 1945 * block Ack Request arrived - release stored frames */ 1946 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) { 1947 /* new head to the ordering buffer */ 1948 if (bar_req) 1949 head_seq_num = mpdu_seq_num; 1950 else 1951 head_seq_num = 1952 seq_inc(seq_sub(mpdu_seq_num, buf_size)); 1953 /* release stored frames up to new head to stack */ 1954 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 1955 index = seq_sub(tid_agg_rx->head_seq_num, 1956 tid_agg_rx->ssn) 1957 % tid_agg_rx->buf_size; 1958 1959 if (tid_agg_rx->reorder_buf[index]) { 1960 /* release the reordered frames to stack */ 1961 memcpy(&status, 1962 tid_agg_rx->reorder_buf[index]->cb, 1963 sizeof(status)); 1964 sband = local->hw.wiphy->bands[status.band]; 1965 rate = &sband->bitrates[status.rate_idx]; 1966 __ieee80211_rx_handle_packet(hw, 1967 tid_agg_rx->reorder_buf[index], 1968 &status, rate); 1969 tid_agg_rx->stored_mpdu_num--; 1970 tid_agg_rx->reorder_buf[index] = NULL; 1971 } 1972 tid_agg_rx->head_seq_num = 1973 seq_inc(tid_agg_rx->head_seq_num); 1974 } 1975 if (bar_req) 1976 return 1; 1977 } 1978 1979 /* now the new frame is always in the range of the reordering */ 1980 /* buffer window */ 1981 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) 1982 % tid_agg_rx->buf_size; 1983 /* check if we already stored this frame */ 1984 if (tid_agg_rx->reorder_buf[index]) { 1985 dev_kfree_skb(skb); 1986 return 1; 1987 } 1988 1989 /* if arrived mpdu is in the right order and nothing else stored */ 1990 /* release it immediately */ 1991 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 1992 tid_agg_rx->stored_mpdu_num == 0) { 1993 tid_agg_rx->head_seq_num = 1994 seq_inc(tid_agg_rx->head_seq_num); 1995 return 0; 1996 } 1997 1998 /* put the frame in the reordering buffer */ 1999 tid_agg_rx->reorder_buf[index] = skb; 2000 tid_agg_rx->stored_mpdu_num++; 2001 /* release the buffer until next missing frame */ 2002 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) 2003 % tid_agg_rx->buf_size; 2004 while (tid_agg_rx->reorder_buf[index]) { 2005 /* release the reordered frame back to stack */ 2006 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb, 2007 sizeof(status)); 2008 sband = local->hw.wiphy->bands[status.band]; 2009 rate = &sband->bitrates[status.rate_idx]; 2010 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index], 2011 &status, rate); 2012 tid_agg_rx->stored_mpdu_num--; 2013 tid_agg_rx->reorder_buf[index] = NULL; 2014 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 2015 index = seq_sub(tid_agg_rx->head_seq_num, 2016 tid_agg_rx->ssn) % tid_agg_rx->buf_size; 2017 } 2018 return 1; 2019 } 2020 2021 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local, 2022 struct sk_buff *skb) 2023 { 2024 struct ieee80211_hw *hw = &local->hw; 2025 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 2026 struct sta_info *sta; 2027 struct tid_ampdu_rx *tid_agg_rx; 2028 u16 sc; 2029 u16 mpdu_seq_num; 2030 u8 ret = 0; 2031 int tid; 2032 2033 sta = sta_info_get(local, hdr->addr2); 2034 if (!sta) 2035 return ret; 2036 2037 /* filter the QoS data rx stream according to 2038 * STA/TID and check if this STA/TID is on aggregation */ 2039 if (!ieee80211_is_data_qos(hdr->frame_control)) 2040 goto end_reorder; 2041 2042 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 2043 2044 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) 2045 goto end_reorder; 2046 2047 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; 2048 2049 /* qos null data frames are excluded */ 2050 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 2051 goto end_reorder; 2052 2053 /* new un-ordered ampdu frame - process it */ 2054 2055 /* reset session timer */ 2056 if (tid_agg_rx->timeout) { 2057 unsigned long expires = 2058 jiffies + (tid_agg_rx->timeout / 1000) * HZ; 2059 mod_timer(&tid_agg_rx->session_timer, expires); 2060 } 2061 2062 /* if this mpdu is fragmented - terminate rx aggregation session */ 2063 sc = le16_to_cpu(hdr->seq_ctrl); 2064 if (sc & IEEE80211_SCTL_FRAG) { 2065 ieee80211_sta_stop_rx_ba_session(sta->sdata->dev, sta->addr, 2066 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP); 2067 ret = 1; 2068 goto end_reorder; 2069 } 2070 2071 /* according to mpdu sequence number deal with reordering buffer */ 2072 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 2073 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, 2074 mpdu_seq_num, 0); 2075 end_reorder: 2076 return ret; 2077 } 2078 2079 /* 2080 * This is the receive path handler. It is called by a low level driver when an 2081 * 802.11 MPDU is received from the hardware. 2082 */ 2083 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, 2084 struct ieee80211_rx_status *status) 2085 { 2086 struct ieee80211_local *local = hw_to_local(hw); 2087 struct ieee80211_rate *rate = NULL; 2088 struct ieee80211_supported_band *sband; 2089 2090 if (status->band < 0 || 2091 status->band >= IEEE80211_NUM_BANDS) { 2092 WARN_ON(1); 2093 return; 2094 } 2095 2096 sband = local->hw.wiphy->bands[status->band]; 2097 2098 if (!sband || 2099 status->rate_idx < 0 || 2100 status->rate_idx >= sband->n_bitrates) { 2101 WARN_ON(1); 2102 return; 2103 } 2104 2105 rate = &sband->bitrates[status->rate_idx]; 2106 2107 /* 2108 * key references and virtual interfaces are protected using RCU 2109 * and this requires that we are in a read-side RCU section during 2110 * receive processing 2111 */ 2112 rcu_read_lock(); 2113 2114 /* 2115 * Frames with failed FCS/PLCP checksum are not returned, 2116 * all other frames are returned without radiotap header 2117 * if it was previously present. 2118 * Also, frames with less than 16 bytes are dropped. 2119 */ 2120 skb = ieee80211_rx_monitor(local, skb, status, rate); 2121 if (!skb) { 2122 rcu_read_unlock(); 2123 return; 2124 } 2125 2126 if (!ieee80211_rx_reorder_ampdu(local, skb)) 2127 __ieee80211_rx_handle_packet(hw, skb, status, rate); 2128 2129 rcu_read_unlock(); 2130 } 2131 EXPORT_SYMBOL(__ieee80211_rx); 2132 2133 /* This is a version of the rx handler that can be called from hard irq 2134 * context. Post the skb on the queue and schedule the tasklet */ 2135 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, 2136 struct ieee80211_rx_status *status) 2137 { 2138 struct ieee80211_local *local = hw_to_local(hw); 2139 2140 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2141 2142 skb->dev = local->mdev; 2143 /* copy status into skb->cb for use by tasklet */ 2144 memcpy(skb->cb, status, sizeof(*status)); 2145 skb->pkt_type = IEEE80211_RX_MSG; 2146 skb_queue_tail(&local->skb_queue, skb); 2147 tasklet_schedule(&local->tasklet); 2148 } 2149 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2150