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 2007-2010 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/slab.h> 14 #include <linux/kernel.h> 15 #include <linux/skbuff.h> 16 #include <linux/netdevice.h> 17 #include <linux/etherdevice.h> 18 #include <linux/rcupdate.h> 19 #include <net/mac80211.h> 20 #include <net/ieee80211_radiotap.h> 21 22 #include "ieee80211_i.h" 23 #include "driver-ops.h" 24 #include "led.h" 25 #include "mesh.h" 26 #include "wep.h" 27 #include "wpa.h" 28 #include "tkip.h" 29 #include "wme.h" 30 31 /* 32 * monitor mode reception 33 * 34 * This function cleans up the SKB, i.e. it removes all the stuff 35 * only useful for monitoring. 36 */ 37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 38 struct sk_buff *skb) 39 { 40 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 41 if (likely(skb->len > FCS_LEN)) 42 __pskb_trim(skb, skb->len - FCS_LEN); 43 else { 44 /* driver bug */ 45 WARN_ON(1); 46 dev_kfree_skb(skb); 47 skb = NULL; 48 } 49 } 50 51 return skb; 52 } 53 54 static inline int should_drop_frame(struct sk_buff *skb, 55 int present_fcs_len) 56 { 57 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 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)) 63 return 1; 64 if (ieee80211_is_ctl(hdr->frame_control) && 65 !ieee80211_is_pspoll(hdr->frame_control) && 66 !ieee80211_is_back_req(hdr->frame_control)) 67 return 1; 68 return 0; 69 } 70 71 static int 72 ieee80211_rx_radiotap_len(struct ieee80211_local *local, 73 struct ieee80211_rx_status *status) 74 { 75 int len; 76 77 /* always present fields */ 78 len = sizeof(struct ieee80211_radiotap_header) + 9; 79 80 if (status->flag & RX_FLAG_TSFT) 81 len += 8; 82 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) 83 len += 1; 84 85 if (len & 1) /* padding for RX_FLAGS if necessary */ 86 len++; 87 88 return len; 89 } 90 91 /* 92 * ieee80211_add_rx_radiotap_header - add radiotap header 93 * 94 * add a radiotap header containing all the fields which the hardware provided. 95 */ 96 static void 97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 98 struct sk_buff *skb, 99 struct ieee80211_rate *rate, 100 int rtap_len) 101 { 102 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 103 struct ieee80211_radiotap_header *rthdr; 104 unsigned char *pos; 105 u16 rx_flags = 0; 106 107 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 108 memset(rthdr, 0, rtap_len); 109 110 /* radiotap header, set always present flags */ 111 rthdr->it_present = 112 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 113 (1 << IEEE80211_RADIOTAP_CHANNEL) | 114 (1 << IEEE80211_RADIOTAP_ANTENNA) | 115 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 116 rthdr->it_len = cpu_to_le16(rtap_len); 117 118 pos = (unsigned char *)(rthdr+1); 119 120 /* the order of the following fields is important */ 121 122 /* IEEE80211_RADIOTAP_TSFT */ 123 if (status->flag & RX_FLAG_TSFT) { 124 put_unaligned_le64(status->mactime, pos); 125 rthdr->it_present |= 126 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 127 pos += 8; 128 } 129 130 /* IEEE80211_RADIOTAP_FLAGS */ 131 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 132 *pos |= IEEE80211_RADIOTAP_F_FCS; 133 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 134 *pos |= IEEE80211_RADIOTAP_F_BADFCS; 135 if (status->flag & RX_FLAG_SHORTPRE) 136 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; 137 pos++; 138 139 /* IEEE80211_RADIOTAP_RATE */ 140 if (status->flag & RX_FLAG_HT) { 141 /* 142 * TODO: add following information into radiotap header once 143 * suitable fields are defined for it: 144 * - MCS index (status->rate_idx) 145 * - HT40 (status->flag & RX_FLAG_40MHZ) 146 * - short-GI (status->flag & RX_FLAG_SHORT_GI) 147 */ 148 *pos = 0; 149 } else { 150 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 151 *pos = rate->bitrate / 5; 152 } 153 pos++; 154 155 /* IEEE80211_RADIOTAP_CHANNEL */ 156 put_unaligned_le16(status->freq, pos); 157 pos += 2; 158 if (status->band == IEEE80211_BAND_5GHZ) 159 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ, 160 pos); 161 else if (status->flag & RX_FLAG_HT) 162 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ, 163 pos); 164 else if (rate->flags & IEEE80211_RATE_ERP_G) 165 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ, 166 pos); 167 else 168 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ, 169 pos); 170 pos += 2; 171 172 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ 173 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { 174 *pos = status->signal; 175 rthdr->it_present |= 176 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); 177 pos++; 178 } 179 180 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ 181 182 /* IEEE80211_RADIOTAP_ANTENNA */ 183 *pos = status->antenna; 184 pos++; 185 186 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ 187 188 /* IEEE80211_RADIOTAP_RX_FLAGS */ 189 /* ensure 2 byte alignment for the 2 byte field as required */ 190 if ((pos - (u8 *)rthdr) & 1) 191 pos++; 192 if (status->flag & RX_FLAG_FAILED_PLCP_CRC) 193 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP; 194 put_unaligned_le16(rx_flags, pos); 195 pos += 2; 196 } 197 198 /* 199 * This function copies a received frame to all monitor interfaces and 200 * returns a cleaned-up SKB that no longer includes the FCS nor the 201 * radiotap header the driver might have added. 202 */ 203 static struct sk_buff * 204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 205 struct ieee80211_rate *rate) 206 { 207 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); 208 struct ieee80211_sub_if_data *sdata; 209 int needed_headroom = 0; 210 struct sk_buff *skb, *skb2; 211 struct net_device *prev_dev = NULL; 212 int present_fcs_len = 0; 213 214 /* 215 * First, we may need to make a copy of the skb because 216 * (1) we need to modify it for radiotap (if not present), and 217 * (2) the other RX handlers will modify the skb we got. 218 * 219 * We don't need to, of course, if we aren't going to return 220 * the SKB because it has a bad FCS/PLCP checksum. 221 */ 222 223 /* room for the radiotap header based on driver features */ 224 needed_headroom = ieee80211_rx_radiotap_len(local, status); 225 226 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 227 present_fcs_len = FCS_LEN; 228 229 /* make sure hdr->frame_control is on the linear part */ 230 if (!pskb_may_pull(origskb, 2)) { 231 dev_kfree_skb(origskb); 232 return NULL; 233 } 234 235 if (!local->monitors) { 236 if (should_drop_frame(origskb, present_fcs_len)) { 237 dev_kfree_skb(origskb); 238 return NULL; 239 } 240 241 return remove_monitor_info(local, origskb); 242 } 243 244 if (should_drop_frame(origskb, present_fcs_len)) { 245 /* only need to expand headroom if necessary */ 246 skb = origskb; 247 origskb = NULL; 248 249 /* 250 * This shouldn't trigger often because most devices have an 251 * RX header they pull before we get here, and that should 252 * be big enough for our radiotap information. We should 253 * probably export the length to drivers so that we can have 254 * them allocate enough headroom to start with. 255 */ 256 if (skb_headroom(skb) < needed_headroom && 257 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) { 258 dev_kfree_skb(skb); 259 return NULL; 260 } 261 } else { 262 /* 263 * Need to make a copy and possibly remove radiotap header 264 * and FCS from the original. 265 */ 266 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 267 268 origskb = remove_monitor_info(local, origskb); 269 270 if (!skb) 271 return origskb; 272 } 273 274 /* prepend radiotap information */ 275 ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom); 276 277 skb_reset_mac_header(skb); 278 skb->ip_summed = CHECKSUM_UNNECESSARY; 279 skb->pkt_type = PACKET_OTHERHOST; 280 skb->protocol = htons(ETH_P_802_2); 281 282 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 283 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) 284 continue; 285 286 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 287 continue; 288 289 if (!ieee80211_sdata_running(sdata)) 290 continue; 291 292 if (prev_dev) { 293 skb2 = skb_clone(skb, GFP_ATOMIC); 294 if (skb2) { 295 skb2->dev = prev_dev; 296 netif_rx(skb2); 297 } 298 } 299 300 prev_dev = sdata->dev; 301 sdata->dev->stats.rx_packets++; 302 sdata->dev->stats.rx_bytes += skb->len; 303 } 304 305 if (prev_dev) { 306 skb->dev = prev_dev; 307 netif_rx(skb); 308 } else 309 dev_kfree_skb(skb); 310 311 return origskb; 312 } 313 314 315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 316 { 317 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 318 int tid; 319 320 /* does the frame have a qos control field? */ 321 if (ieee80211_is_data_qos(hdr->frame_control)) { 322 u8 *qc = ieee80211_get_qos_ctl(hdr); 323 /* frame has qos control */ 324 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 325 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 326 rx->flags |= IEEE80211_RX_AMSDU; 327 else 328 rx->flags &= ~IEEE80211_RX_AMSDU; 329 } else { 330 /* 331 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 332 * 333 * Sequence numbers for management frames, QoS data 334 * frames with a broadcast/multicast address in the 335 * Address 1 field, and all non-QoS data frames sent 336 * by QoS STAs are assigned using an additional single 337 * modulo-4096 counter, [...] 338 * 339 * We also use that counter for non-QoS STAs. 340 */ 341 tid = NUM_RX_DATA_QUEUES - 1; 342 } 343 344 rx->queue = tid; 345 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 346 * For now, set skb->priority to 0 for other cases. */ 347 rx->skb->priority = (tid > 7) ? 0 : tid; 348 } 349 350 /** 351 * DOC: Packet alignment 352 * 353 * Drivers always need to pass packets that are aligned to two-byte boundaries 354 * to the stack. 355 * 356 * Additionally, should, if possible, align the payload data in a way that 357 * guarantees that the contained IP header is aligned to a four-byte 358 * boundary. In the case of regular frames, this simply means aligning the 359 * payload to a four-byte boundary (because either the IP header is directly 360 * contained, or IV/RFC1042 headers that have a length divisible by four are 361 * in front of it). If the payload data is not properly aligned and the 362 * architecture doesn't support efficient unaligned operations, mac80211 363 * will align the data. 364 * 365 * With A-MSDU frames, however, the payload data address must yield two modulo 366 * four because there are 14-byte 802.3 headers within the A-MSDU frames that 367 * push the IP header further back to a multiple of four again. Thankfully, the 368 * specs were sane enough this time around to require padding each A-MSDU 369 * subframe to a length that is a multiple of four. 370 * 371 * Padding like Atheros hardware adds which is inbetween the 802.11 header and 372 * the payload is not supported, the driver is required to move the 802.11 373 * header to be directly in front of the payload in that case. 374 */ 375 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) 376 { 377 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 378 WARN_ONCE((unsigned long)rx->skb->data & 1, 379 "unaligned packet at 0x%p\n", rx->skb->data); 380 #endif 381 } 382 383 384 /* rx handlers */ 385 386 static ieee80211_rx_result debug_noinline 387 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 388 { 389 struct ieee80211_local *local = rx->local; 390 struct sk_buff *skb = rx->skb; 391 392 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning))) 393 return ieee80211_scan_rx(rx->sdata, skb); 394 395 if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) && 396 (rx->flags & IEEE80211_RX_IN_SCAN))) { 397 /* drop all the other packets during a software scan anyway */ 398 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED) 399 dev_kfree_skb(skb); 400 return RX_QUEUED; 401 } 402 403 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { 404 /* scanning finished during invoking of handlers */ 405 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 406 return RX_DROP_UNUSABLE; 407 } 408 409 return RX_CONTINUE; 410 } 411 412 413 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) 414 { 415 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 416 417 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) 418 return 0; 419 420 return ieee80211_is_robust_mgmt_frame(hdr); 421 } 422 423 424 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) 425 { 426 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 427 428 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) 429 return 0; 430 431 return ieee80211_is_robust_mgmt_frame(hdr); 432 } 433 434 435 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ 436 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) 437 { 438 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; 439 struct ieee80211_mmie *mmie; 440 441 if (skb->len < 24 + sizeof(*mmie) || 442 !is_multicast_ether_addr(hdr->da)) 443 return -1; 444 445 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) 446 return -1; /* not a robust management frame */ 447 448 mmie = (struct ieee80211_mmie *) 449 (skb->data + skb->len - sizeof(*mmie)); 450 if (mmie->element_id != WLAN_EID_MMIE || 451 mmie->length != sizeof(*mmie) - 2) 452 return -1; 453 454 return le16_to_cpu(mmie->key_id); 455 } 456 457 458 static ieee80211_rx_result 459 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 460 { 461 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 462 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 463 char *dev_addr = rx->sdata->vif.addr; 464 465 if (ieee80211_is_data(hdr->frame_control)) { 466 if (is_multicast_ether_addr(hdr->addr1)) { 467 if (ieee80211_has_tods(hdr->frame_control) || 468 !ieee80211_has_fromds(hdr->frame_control)) 469 return RX_DROP_MONITOR; 470 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0) 471 return RX_DROP_MONITOR; 472 } else { 473 if (!ieee80211_has_a4(hdr->frame_control)) 474 return RX_DROP_MONITOR; 475 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0) 476 return RX_DROP_MONITOR; 477 } 478 } 479 480 /* If there is not an established peer link and this is not a peer link 481 * establisment frame, beacon or probe, drop the frame. 482 */ 483 484 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 485 struct ieee80211_mgmt *mgmt; 486 487 if (!ieee80211_is_mgmt(hdr->frame_control)) 488 return RX_DROP_MONITOR; 489 490 if (ieee80211_is_action(hdr->frame_control)) { 491 mgmt = (struct ieee80211_mgmt *)hdr; 492 if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK) 493 return RX_DROP_MONITOR; 494 return RX_CONTINUE; 495 } 496 497 if (ieee80211_is_probe_req(hdr->frame_control) || 498 ieee80211_is_probe_resp(hdr->frame_control) || 499 ieee80211_is_beacon(hdr->frame_control)) 500 return RX_CONTINUE; 501 502 return RX_DROP_MONITOR; 503 504 } 505 506 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 507 508 if (ieee80211_is_data(hdr->frame_control) && 509 is_multicast_ether_addr(hdr->addr1) && 510 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata)) 511 return RX_DROP_MONITOR; 512 #undef msh_h_get 513 514 return RX_CONTINUE; 515 } 516 517 #define SEQ_MODULO 0x1000 518 #define SEQ_MASK 0xfff 519 520 static inline int seq_less(u16 sq1, u16 sq2) 521 { 522 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); 523 } 524 525 static inline u16 seq_inc(u16 sq) 526 { 527 return (sq + 1) & SEQ_MASK; 528 } 529 530 static inline u16 seq_sub(u16 sq1, u16 sq2) 531 { 532 return (sq1 - sq2) & SEQ_MASK; 533 } 534 535 536 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, 537 struct tid_ampdu_rx *tid_agg_rx, 538 int index, 539 struct sk_buff_head *frames) 540 { 541 struct ieee80211_supported_band *sband; 542 struct ieee80211_rate *rate = NULL; 543 struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; 544 struct ieee80211_rx_status *status; 545 546 if (!skb) 547 goto no_frame; 548 549 status = IEEE80211_SKB_RXCB(skb); 550 551 /* release the reordered frames to stack */ 552 sband = hw->wiphy->bands[status->band]; 553 if (!(status->flag & RX_FLAG_HT)) 554 rate = &sband->bitrates[status->rate_idx]; 555 tid_agg_rx->stored_mpdu_num--; 556 tid_agg_rx->reorder_buf[index] = NULL; 557 __skb_queue_tail(frames, skb); 558 559 no_frame: 560 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 561 } 562 563 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw, 564 struct tid_ampdu_rx *tid_agg_rx, 565 u16 head_seq_num, 566 struct sk_buff_head *frames) 567 { 568 int index; 569 570 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 571 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 572 tid_agg_rx->buf_size; 573 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); 574 } 575 } 576 577 /* 578 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If 579 * the skb was added to the buffer longer than this time ago, the earlier 580 * frames that have not yet been received are assumed to be lost and the skb 581 * can be released for processing. This may also release other skb's from the 582 * reorder buffer if there are no additional gaps between the frames. 583 */ 584 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) 585 586 /* 587 * As this function belongs to the RX path it must be under 588 * rcu_read_lock protection. It returns false if the frame 589 * can be processed immediately, true if it was consumed. 590 */ 591 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 592 struct tid_ampdu_rx *tid_agg_rx, 593 struct sk_buff *skb, 594 struct sk_buff_head *frames) 595 { 596 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 597 u16 sc = le16_to_cpu(hdr->seq_ctrl); 598 u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 599 u16 head_seq_num, buf_size; 600 int index; 601 602 buf_size = tid_agg_rx->buf_size; 603 head_seq_num = tid_agg_rx->head_seq_num; 604 605 /* frame with out of date sequence number */ 606 if (seq_less(mpdu_seq_num, head_seq_num)) { 607 dev_kfree_skb(skb); 608 return true; 609 } 610 611 /* 612 * If frame the sequence number exceeds our buffering window 613 * size release some previous frames to make room for this one. 614 */ 615 if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) { 616 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size)); 617 /* release stored frames up to new head to stack */ 618 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num, 619 frames); 620 } 621 622 /* Now the new frame is always in the range of the reordering buffer */ 623 624 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; 625 626 /* check if we already stored this frame */ 627 if (tid_agg_rx->reorder_buf[index]) { 628 dev_kfree_skb(skb); 629 return true; 630 } 631 632 /* 633 * If the current MPDU is in the right order and nothing else 634 * is stored we can process it directly, no need to buffer it. 635 */ 636 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 637 tid_agg_rx->stored_mpdu_num == 0) { 638 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 639 return false; 640 } 641 642 /* put the frame in the reordering buffer */ 643 tid_agg_rx->reorder_buf[index] = skb; 644 tid_agg_rx->reorder_time[index] = jiffies; 645 tid_agg_rx->stored_mpdu_num++; 646 /* release the buffer until next missing frame */ 647 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 648 tid_agg_rx->buf_size; 649 if (!tid_agg_rx->reorder_buf[index] && 650 tid_agg_rx->stored_mpdu_num > 1) { 651 /* 652 * No buffers ready to be released, but check whether any 653 * frames in the reorder buffer have timed out. 654 */ 655 int j; 656 int skipped = 1; 657 for (j = (index + 1) % tid_agg_rx->buf_size; j != index; 658 j = (j + 1) % tid_agg_rx->buf_size) { 659 if (!tid_agg_rx->reorder_buf[j]) { 660 skipped++; 661 continue; 662 } 663 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + 664 HT_RX_REORDER_BUF_TIMEOUT)) 665 break; 666 667 #ifdef CONFIG_MAC80211_HT_DEBUG 668 if (net_ratelimit()) 669 printk(KERN_DEBUG "%s: release an RX reorder " 670 "frame due to timeout on earlier " 671 "frames\n", 672 wiphy_name(hw->wiphy)); 673 #endif 674 ieee80211_release_reorder_frame(hw, tid_agg_rx, 675 j, frames); 676 677 /* 678 * Increment the head seq# also for the skipped slots. 679 */ 680 tid_agg_rx->head_seq_num = 681 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK; 682 skipped = 0; 683 } 684 } else while (tid_agg_rx->reorder_buf[index]) { 685 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); 686 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 687 tid_agg_rx->buf_size; 688 } 689 690 return true; 691 } 692 693 /* 694 * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns 695 * true if the MPDU was buffered, false if it should be processed. 696 */ 697 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx, 698 struct sk_buff_head *frames) 699 { 700 struct sk_buff *skb = rx->skb; 701 struct ieee80211_local *local = rx->local; 702 struct ieee80211_hw *hw = &local->hw; 703 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 704 struct sta_info *sta = rx->sta; 705 struct tid_ampdu_rx *tid_agg_rx; 706 u16 sc; 707 int tid; 708 709 if (!ieee80211_is_data_qos(hdr->frame_control)) 710 goto dont_reorder; 711 712 /* 713 * filter the QoS data rx stream according to 714 * STA/TID and check if this STA/TID is on aggregation 715 */ 716 717 if (!sta) 718 goto dont_reorder; 719 720 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 721 722 spin_lock(&sta->lock); 723 724 if (!sta->ampdu_mlme.tid_active_rx[tid]) 725 goto dont_reorder_unlock; 726 727 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; 728 729 /* qos null data frames are excluded */ 730 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 731 goto dont_reorder_unlock; 732 733 /* new, potentially un-ordered, ampdu frame - process it */ 734 735 /* reset session timer */ 736 if (tid_agg_rx->timeout) 737 mod_timer(&tid_agg_rx->session_timer, 738 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 739 740 /* if this mpdu is fragmented - terminate rx aggregation session */ 741 sc = le16_to_cpu(hdr->seq_ctrl); 742 if (sc & IEEE80211_SCTL_FRAG) { 743 spin_unlock(&sta->lock); 744 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 745 WLAN_REASON_QSTA_REQUIRE_SETUP); 746 dev_kfree_skb(skb); 747 return; 748 } 749 750 if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames)) { 751 spin_unlock(&sta->lock); 752 return; 753 } 754 755 dont_reorder_unlock: 756 spin_unlock(&sta->lock); 757 dont_reorder: 758 __skb_queue_tail(frames, skb); 759 } 760 761 static ieee80211_rx_result debug_noinline 762 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 763 { 764 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 765 766 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 767 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 768 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 769 rx->sta->last_seq_ctrl[rx->queue] == 770 hdr->seq_ctrl)) { 771 if (rx->flags & IEEE80211_RX_RA_MATCH) { 772 rx->local->dot11FrameDuplicateCount++; 773 rx->sta->num_duplicates++; 774 } 775 return RX_DROP_MONITOR; 776 } else 777 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 778 } 779 780 if (unlikely(rx->skb->len < 16)) { 781 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 782 return RX_DROP_MONITOR; 783 } 784 785 /* Drop disallowed frame classes based on STA auth/assoc state; 786 * IEEE 802.11, Chap 5.5. 787 * 788 * mac80211 filters only based on association state, i.e. it drops 789 * Class 3 frames from not associated stations. hostapd sends 790 * deauth/disassoc frames when needed. In addition, hostapd is 791 * responsible for filtering on both auth and assoc states. 792 */ 793 794 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 795 return ieee80211_rx_mesh_check(rx); 796 797 if (unlikely((ieee80211_is_data(hdr->frame_control) || 798 ieee80211_is_pspoll(hdr->frame_control)) && 799 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 800 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 801 if ((!ieee80211_has_fromds(hdr->frame_control) && 802 !ieee80211_has_tods(hdr->frame_control) && 803 ieee80211_is_data(hdr->frame_control)) || 804 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 805 /* Drop IBSS frames and frames for other hosts 806 * silently. */ 807 return RX_DROP_MONITOR; 808 } 809 810 return RX_DROP_MONITOR; 811 } 812 813 return RX_CONTINUE; 814 } 815 816 817 static ieee80211_rx_result debug_noinline 818 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 819 { 820 struct sk_buff *skb = rx->skb; 821 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 822 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 823 int keyidx; 824 int hdrlen; 825 ieee80211_rx_result result = RX_DROP_UNUSABLE; 826 struct ieee80211_key *stakey = NULL; 827 int mmie_keyidx = -1; 828 829 /* 830 * Key selection 101 831 * 832 * There are four types of keys: 833 * - GTK (group keys) 834 * - IGTK (group keys for management frames) 835 * - PTK (pairwise keys) 836 * - STK (station-to-station pairwise keys) 837 * 838 * When selecting a key, we have to distinguish between multicast 839 * (including broadcast) and unicast frames, the latter can only 840 * use PTKs and STKs while the former always use GTKs and IGTKs. 841 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 842 * unicast frames can also use key indices like GTKs. Hence, if we 843 * don't have a PTK/STK we check the key index for a WEP key. 844 * 845 * Note that in a regular BSS, multicast frames are sent by the 846 * AP only, associated stations unicast the frame to the AP first 847 * which then multicasts it on their behalf. 848 * 849 * There is also a slight problem in IBSS mode: GTKs are negotiated 850 * with each station, that is something we don't currently handle. 851 * The spec seems to expect that one negotiates the same key with 852 * every station but there's no such requirement; VLANs could be 853 * possible. 854 */ 855 856 /* 857 * No point in finding a key and decrypting if the frame is neither 858 * addressed to us nor a multicast frame. 859 */ 860 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 861 return RX_CONTINUE; 862 863 /* start without a key */ 864 rx->key = NULL; 865 866 if (rx->sta) 867 stakey = rcu_dereference(rx->sta->key); 868 869 if (!ieee80211_has_protected(hdr->frame_control)) 870 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 871 872 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 873 rx->key = stakey; 874 /* Skip decryption if the frame is not protected. */ 875 if (!ieee80211_has_protected(hdr->frame_control)) 876 return RX_CONTINUE; 877 } else if (mmie_keyidx >= 0) { 878 /* Broadcast/multicast robust management frame / BIP */ 879 if ((status->flag & RX_FLAG_DECRYPTED) && 880 (status->flag & RX_FLAG_IV_STRIPPED)) 881 return RX_CONTINUE; 882 883 if (mmie_keyidx < NUM_DEFAULT_KEYS || 884 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 885 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 886 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 887 } else if (!ieee80211_has_protected(hdr->frame_control)) { 888 /* 889 * The frame was not protected, so skip decryption. However, we 890 * need to set rx->key if there is a key that could have been 891 * used so that the frame may be dropped if encryption would 892 * have been expected. 893 */ 894 struct ieee80211_key *key = NULL; 895 if (ieee80211_is_mgmt(hdr->frame_control) && 896 is_multicast_ether_addr(hdr->addr1) && 897 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 898 rx->key = key; 899 else if ((key = rcu_dereference(rx->sdata->default_key))) 900 rx->key = key; 901 return RX_CONTINUE; 902 } else { 903 u8 keyid; 904 /* 905 * The device doesn't give us the IV so we won't be 906 * able to look up the key. That's ok though, we 907 * don't need to decrypt the frame, we just won't 908 * be able to keep statistics accurate. 909 * Except for key threshold notifications, should 910 * we somehow allow the driver to tell us which key 911 * the hardware used if this flag is set? 912 */ 913 if ((status->flag & RX_FLAG_DECRYPTED) && 914 (status->flag & RX_FLAG_IV_STRIPPED)) 915 return RX_CONTINUE; 916 917 hdrlen = ieee80211_hdrlen(hdr->frame_control); 918 919 if (rx->skb->len < 8 + hdrlen) 920 return RX_DROP_UNUSABLE; /* TODO: count this? */ 921 922 /* 923 * no need to call ieee80211_wep_get_keyidx, 924 * it verifies a bunch of things we've done already 925 */ 926 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1); 927 keyidx = keyid >> 6; 928 929 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 930 931 /* 932 * RSNA-protected unicast frames should always be sent with 933 * pairwise or station-to-station keys, but for WEP we allow 934 * using a key index as well. 935 */ 936 if (rx->key && rx->key->conf.alg != ALG_WEP && 937 !is_multicast_ether_addr(hdr->addr1)) 938 rx->key = NULL; 939 } 940 941 if (rx->key) { 942 rx->key->tx_rx_count++; 943 /* TODO: add threshold stuff again */ 944 } else { 945 return RX_DROP_MONITOR; 946 } 947 948 if (skb_linearize(rx->skb)) 949 return RX_DROP_UNUSABLE; 950 951 hdr = (struct ieee80211_hdr *)rx->skb->data; 952 953 /* Check for weak IVs if possible */ 954 if (rx->sta && rx->key->conf.alg == ALG_WEP && 955 ieee80211_is_data(hdr->frame_control) && 956 (!(status->flag & RX_FLAG_IV_STRIPPED) || 957 !(status->flag & RX_FLAG_DECRYPTED)) && 958 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 959 rx->sta->wep_weak_iv_count++; 960 961 switch (rx->key->conf.alg) { 962 case ALG_WEP: 963 result = ieee80211_crypto_wep_decrypt(rx); 964 break; 965 case ALG_TKIP: 966 result = ieee80211_crypto_tkip_decrypt(rx); 967 break; 968 case ALG_CCMP: 969 result = ieee80211_crypto_ccmp_decrypt(rx); 970 break; 971 case ALG_AES_CMAC: 972 result = ieee80211_crypto_aes_cmac_decrypt(rx); 973 break; 974 } 975 976 /* either the frame has been decrypted or will be dropped */ 977 status->flag |= RX_FLAG_DECRYPTED; 978 979 return result; 980 } 981 982 static ieee80211_rx_result debug_noinline 983 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 984 { 985 struct ieee80211_local *local; 986 struct ieee80211_hdr *hdr; 987 struct sk_buff *skb; 988 989 local = rx->local; 990 skb = rx->skb; 991 hdr = (struct ieee80211_hdr *) skb->data; 992 993 if (!local->pspolling) 994 return RX_CONTINUE; 995 996 if (!ieee80211_has_fromds(hdr->frame_control)) 997 /* this is not from AP */ 998 return RX_CONTINUE; 999 1000 if (!ieee80211_is_data(hdr->frame_control)) 1001 return RX_CONTINUE; 1002 1003 if (!ieee80211_has_moredata(hdr->frame_control)) { 1004 /* AP has no more frames buffered for us */ 1005 local->pspolling = false; 1006 return RX_CONTINUE; 1007 } 1008 1009 /* more data bit is set, let's request a new frame from the AP */ 1010 ieee80211_send_pspoll(local, rx->sdata); 1011 1012 return RX_CONTINUE; 1013 } 1014 1015 static void ap_sta_ps_start(struct sta_info *sta) 1016 { 1017 struct ieee80211_sub_if_data *sdata = sta->sdata; 1018 struct ieee80211_local *local = sdata->local; 1019 1020 atomic_inc(&sdata->bss->num_sta_ps); 1021 set_sta_flags(sta, WLAN_STA_PS_STA); 1022 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); 1023 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1024 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 1025 sdata->name, sta->sta.addr, sta->sta.aid); 1026 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1027 } 1028 1029 static void ap_sta_ps_end(struct sta_info *sta) 1030 { 1031 struct ieee80211_sub_if_data *sdata = sta->sdata; 1032 1033 atomic_dec(&sdata->bss->num_sta_ps); 1034 1035 clear_sta_flags(sta, WLAN_STA_PS_STA); 1036 1037 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1038 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 1039 sdata->name, sta->sta.addr, sta->sta.aid); 1040 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1041 1042 if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) { 1043 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1044 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", 1045 sdata->name, sta->sta.addr, sta->sta.aid); 1046 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1047 return; 1048 } 1049 1050 ieee80211_sta_ps_deliver_wakeup(sta); 1051 } 1052 1053 static ieee80211_rx_result debug_noinline 1054 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 1055 { 1056 struct sta_info *sta = rx->sta; 1057 struct sk_buff *skb = rx->skb; 1058 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1059 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1060 1061 if (!sta) 1062 return RX_CONTINUE; 1063 1064 /* 1065 * Update last_rx only for IBSS packets which are for the current 1066 * BSSID to avoid keeping the current IBSS network alive in cases 1067 * where other STAs start using different BSSID. 1068 */ 1069 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 1070 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 1071 NL80211_IFTYPE_ADHOC); 1072 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) 1073 sta->last_rx = jiffies; 1074 } else if (!is_multicast_ether_addr(hdr->addr1)) { 1075 /* 1076 * Mesh beacons will update last_rx when if they are found to 1077 * match the current local configuration when processed. 1078 */ 1079 sta->last_rx = jiffies; 1080 } 1081 1082 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1083 return RX_CONTINUE; 1084 1085 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 1086 ieee80211_sta_rx_notify(rx->sdata, hdr); 1087 1088 sta->rx_fragments++; 1089 sta->rx_bytes += rx->skb->len; 1090 sta->last_signal = status->signal; 1091 1092 /* 1093 * Change STA power saving mode only at the end of a frame 1094 * exchange sequence. 1095 */ 1096 if (!ieee80211_has_morefrags(hdr->frame_control) && 1097 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1098 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 1099 if (test_sta_flags(sta, WLAN_STA_PS_STA)) { 1100 /* 1101 * Ignore doze->wake transitions that are 1102 * indicated by non-data frames, the standard 1103 * is unclear here, but for example going to 1104 * PS mode and then scanning would cause a 1105 * doze->wake transition for the probe request, 1106 * and that is clearly undesirable. 1107 */ 1108 if (ieee80211_is_data(hdr->frame_control) && 1109 !ieee80211_has_pm(hdr->frame_control)) 1110 ap_sta_ps_end(sta); 1111 } else { 1112 if (ieee80211_has_pm(hdr->frame_control)) 1113 ap_sta_ps_start(sta); 1114 } 1115 } 1116 1117 /* 1118 * Drop (qos-)data::nullfunc frames silently, since they 1119 * are used only to control station power saving mode. 1120 */ 1121 if (ieee80211_is_nullfunc(hdr->frame_control) || 1122 ieee80211_is_qos_nullfunc(hdr->frame_control)) { 1123 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 1124 1125 /* 1126 * If we receive a 4-addr nullfunc frame from a STA 1127 * that was not moved to a 4-addr STA vlan yet, drop 1128 * the frame to the monitor interface, to make sure 1129 * that hostapd sees it 1130 */ 1131 if (ieee80211_has_a4(hdr->frame_control) && 1132 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1133 (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1134 !rx->sdata->u.vlan.sta))) 1135 return RX_DROP_MONITOR; 1136 /* 1137 * Update counter and free packet here to avoid 1138 * counting this as a dropped packed. 1139 */ 1140 sta->rx_packets++; 1141 dev_kfree_skb(rx->skb); 1142 return RX_QUEUED; 1143 } 1144 1145 return RX_CONTINUE; 1146 } /* ieee80211_rx_h_sta_process */ 1147 1148 static inline struct ieee80211_fragment_entry * 1149 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 1150 unsigned int frag, unsigned int seq, int rx_queue, 1151 struct sk_buff **skb) 1152 { 1153 struct ieee80211_fragment_entry *entry; 1154 int idx; 1155 1156 idx = sdata->fragment_next; 1157 entry = &sdata->fragments[sdata->fragment_next++]; 1158 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 1159 sdata->fragment_next = 0; 1160 1161 if (!skb_queue_empty(&entry->skb_list)) { 1162 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1163 struct ieee80211_hdr *hdr = 1164 (struct ieee80211_hdr *) entry->skb_list.next->data; 1165 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 1166 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 1167 "addr1=%pM addr2=%pM\n", 1168 sdata->name, idx, 1169 jiffies - entry->first_frag_time, entry->seq, 1170 entry->last_frag, hdr->addr1, hdr->addr2); 1171 #endif 1172 __skb_queue_purge(&entry->skb_list); 1173 } 1174 1175 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 1176 *skb = NULL; 1177 entry->first_frag_time = jiffies; 1178 entry->seq = seq; 1179 entry->rx_queue = rx_queue; 1180 entry->last_frag = frag; 1181 entry->ccmp = 0; 1182 entry->extra_len = 0; 1183 1184 return entry; 1185 } 1186 1187 static inline struct ieee80211_fragment_entry * 1188 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 1189 unsigned int frag, unsigned int seq, 1190 int rx_queue, struct ieee80211_hdr *hdr) 1191 { 1192 struct ieee80211_fragment_entry *entry; 1193 int i, idx; 1194 1195 idx = sdata->fragment_next; 1196 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 1197 struct ieee80211_hdr *f_hdr; 1198 1199 idx--; 1200 if (idx < 0) 1201 idx = IEEE80211_FRAGMENT_MAX - 1; 1202 1203 entry = &sdata->fragments[idx]; 1204 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 1205 entry->rx_queue != rx_queue || 1206 entry->last_frag + 1 != frag) 1207 continue; 1208 1209 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 1210 1211 /* 1212 * Check ftype and addresses are equal, else check next fragment 1213 */ 1214 if (((hdr->frame_control ^ f_hdr->frame_control) & 1215 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 1216 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 1217 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 1218 continue; 1219 1220 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 1221 __skb_queue_purge(&entry->skb_list); 1222 continue; 1223 } 1224 return entry; 1225 } 1226 1227 return NULL; 1228 } 1229 1230 static ieee80211_rx_result debug_noinline 1231 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 1232 { 1233 struct ieee80211_hdr *hdr; 1234 u16 sc; 1235 __le16 fc; 1236 unsigned int frag, seq; 1237 struct ieee80211_fragment_entry *entry; 1238 struct sk_buff *skb; 1239 1240 hdr = (struct ieee80211_hdr *)rx->skb->data; 1241 fc = hdr->frame_control; 1242 sc = le16_to_cpu(hdr->seq_ctrl); 1243 frag = sc & IEEE80211_SCTL_FRAG; 1244 1245 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1246 (rx->skb)->len < 24 || 1247 is_multicast_ether_addr(hdr->addr1))) { 1248 /* not fragmented */ 1249 goto out; 1250 } 1251 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1252 1253 if (skb_linearize(rx->skb)) 1254 return RX_DROP_UNUSABLE; 1255 1256 /* 1257 * skb_linearize() might change the skb->data and 1258 * previously cached variables (in this case, hdr) need to 1259 * be refreshed with the new data. 1260 */ 1261 hdr = (struct ieee80211_hdr *)rx->skb->data; 1262 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1263 1264 if (frag == 0) { 1265 /* This is the first fragment of a new frame. */ 1266 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1267 rx->queue, &(rx->skb)); 1268 if (rx->key && rx->key->conf.alg == ALG_CCMP && 1269 ieee80211_has_protected(fc)) { 1270 /* Store CCMP PN so that we can verify that the next 1271 * fragment has a sequential PN value. */ 1272 entry->ccmp = 1; 1273 memcpy(entry->last_pn, 1274 rx->key->u.ccmp.rx_pn[rx->queue], 1275 CCMP_PN_LEN); 1276 } 1277 return RX_QUEUED; 1278 } 1279 1280 /* This is a fragment for a frame that should already be pending in 1281 * fragment cache. Add this fragment to the end of the pending entry. 1282 */ 1283 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1284 if (!entry) { 1285 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1286 return RX_DROP_MONITOR; 1287 } 1288 1289 /* Verify that MPDUs within one MSDU have sequential PN values. 1290 * (IEEE 802.11i, 8.3.3.4.5) */ 1291 if (entry->ccmp) { 1292 int i; 1293 u8 pn[CCMP_PN_LEN], *rpn; 1294 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 1295 return RX_DROP_UNUSABLE; 1296 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1297 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1298 pn[i]++; 1299 if (pn[i]) 1300 break; 1301 } 1302 rpn = rx->key->u.ccmp.rx_pn[rx->queue]; 1303 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1304 return RX_DROP_UNUSABLE; 1305 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1306 } 1307 1308 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1309 __skb_queue_tail(&entry->skb_list, rx->skb); 1310 entry->last_frag = frag; 1311 entry->extra_len += rx->skb->len; 1312 if (ieee80211_has_morefrags(fc)) { 1313 rx->skb = NULL; 1314 return RX_QUEUED; 1315 } 1316 1317 rx->skb = __skb_dequeue(&entry->skb_list); 1318 if (skb_tailroom(rx->skb) < entry->extra_len) { 1319 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1320 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1321 GFP_ATOMIC))) { 1322 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1323 __skb_queue_purge(&entry->skb_list); 1324 return RX_DROP_UNUSABLE; 1325 } 1326 } 1327 while ((skb = __skb_dequeue(&entry->skb_list))) { 1328 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1329 dev_kfree_skb(skb); 1330 } 1331 1332 /* Complete frame has been reassembled - process it now */ 1333 rx->flags |= IEEE80211_RX_FRAGMENTED; 1334 1335 out: 1336 if (rx->sta) 1337 rx->sta->rx_packets++; 1338 if (is_multicast_ether_addr(hdr->addr1)) 1339 rx->local->dot11MulticastReceivedFrameCount++; 1340 else 1341 ieee80211_led_rx(rx->local); 1342 return RX_CONTINUE; 1343 } 1344 1345 static ieee80211_rx_result debug_noinline 1346 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1347 { 1348 struct ieee80211_sub_if_data *sdata = rx->sdata; 1349 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1350 1351 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1352 !(rx->flags & IEEE80211_RX_RA_MATCH))) 1353 return RX_CONTINUE; 1354 1355 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1356 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1357 return RX_DROP_UNUSABLE; 1358 1359 if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) 1360 ieee80211_sta_ps_deliver_poll_response(rx->sta); 1361 else 1362 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1363 1364 /* Free PS Poll skb here instead of returning RX_DROP that would 1365 * count as an dropped frame. */ 1366 dev_kfree_skb(rx->skb); 1367 1368 return RX_QUEUED; 1369 } 1370 1371 static ieee80211_rx_result debug_noinline 1372 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1373 { 1374 u8 *data = rx->skb->data; 1375 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1376 1377 if (!ieee80211_is_data_qos(hdr->frame_control)) 1378 return RX_CONTINUE; 1379 1380 /* remove the qos control field, update frame type and meta-data */ 1381 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1382 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1383 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1384 /* change frame type to non QOS */ 1385 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1386 1387 return RX_CONTINUE; 1388 } 1389 1390 static int 1391 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1392 { 1393 if (unlikely(!rx->sta || 1394 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1395 return -EACCES; 1396 1397 return 0; 1398 } 1399 1400 static int 1401 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1402 { 1403 struct sk_buff *skb = rx->skb; 1404 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1405 1406 /* 1407 * Pass through unencrypted frames if the hardware has 1408 * decrypted them already. 1409 */ 1410 if (status->flag & RX_FLAG_DECRYPTED) 1411 return 0; 1412 1413 /* Drop unencrypted frames if key is set. */ 1414 if (unlikely(!ieee80211_has_protected(fc) && 1415 !ieee80211_is_nullfunc(fc) && 1416 ieee80211_is_data(fc) && 1417 (rx->key || rx->sdata->drop_unencrypted))) 1418 return -EACCES; 1419 1420 return 0; 1421 } 1422 1423 static int 1424 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) 1425 { 1426 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1427 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1428 __le16 fc = hdr->frame_control; 1429 1430 /* 1431 * Pass through unencrypted frames if the hardware has 1432 * decrypted them already. 1433 */ 1434 if (status->flag & RX_FLAG_DECRYPTED) 1435 return 0; 1436 1437 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1438 if (unlikely(!ieee80211_has_protected(fc) && 1439 ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1440 rx->key)) 1441 return -EACCES; 1442 /* BIP does not use Protected field, so need to check MMIE */ 1443 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && 1444 ieee80211_get_mmie_keyidx(rx->skb) < 0)) 1445 return -EACCES; 1446 /* 1447 * When using MFP, Action frames are not allowed prior to 1448 * having configured keys. 1449 */ 1450 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1451 ieee80211_is_robust_mgmt_frame( 1452 (struct ieee80211_hdr *) rx->skb->data))) 1453 return -EACCES; 1454 } 1455 1456 return 0; 1457 } 1458 1459 static int 1460 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1461 { 1462 struct ieee80211_sub_if_data *sdata = rx->sdata; 1463 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1464 1465 if (ieee80211_has_a4(hdr->frame_control) && 1466 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) 1467 return -1; 1468 1469 if (is_multicast_ether_addr(hdr->addr1) && 1470 ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) || 1471 (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr))) 1472 return -1; 1473 1474 return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); 1475 } 1476 1477 /* 1478 * requires that rx->skb is a frame with ethernet header 1479 */ 1480 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1481 { 1482 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1483 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1484 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1485 1486 /* 1487 * Allow EAPOL frames to us/the PAE group address regardless 1488 * of whether the frame was encrypted or not. 1489 */ 1490 if (ehdr->h_proto == htons(ETH_P_PAE) && 1491 (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || 1492 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1493 return true; 1494 1495 if (ieee80211_802_1x_port_control(rx) || 1496 ieee80211_drop_unencrypted(rx, fc)) 1497 return false; 1498 1499 return true; 1500 } 1501 1502 /* 1503 * requires that rx->skb is a frame with ethernet header 1504 */ 1505 static void 1506 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1507 { 1508 struct ieee80211_sub_if_data *sdata = rx->sdata; 1509 struct net_device *dev = sdata->dev; 1510 struct sk_buff *skb, *xmit_skb; 1511 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1512 struct sta_info *dsta; 1513 1514 skb = rx->skb; 1515 xmit_skb = NULL; 1516 1517 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1518 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1519 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1520 (rx->flags & IEEE80211_RX_RA_MATCH) && 1521 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { 1522 if (is_multicast_ether_addr(ehdr->h_dest)) { 1523 /* 1524 * send multicast frames both to higher layers in 1525 * local net stack and back to the wireless medium 1526 */ 1527 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1528 if (!xmit_skb && net_ratelimit()) 1529 printk(KERN_DEBUG "%s: failed to clone " 1530 "multicast frame\n", dev->name); 1531 } else { 1532 dsta = sta_info_get(sdata, skb->data); 1533 if (dsta) { 1534 /* 1535 * The destination station is associated to 1536 * this AP (in this VLAN), so send the frame 1537 * directly to it and do not pass it to local 1538 * net stack. 1539 */ 1540 xmit_skb = skb; 1541 skb = NULL; 1542 } 1543 } 1544 } 1545 1546 if (skb) { 1547 int align __maybe_unused; 1548 1549 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1550 /* 1551 * 'align' will only take the values 0 or 2 here 1552 * since all frames are required to be aligned 1553 * to 2-byte boundaries when being passed to 1554 * mac80211. That also explains the __skb_push() 1555 * below. 1556 */ 1557 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1558 if (align) { 1559 if (WARN_ON(skb_headroom(skb) < 3)) { 1560 dev_kfree_skb(skb); 1561 skb = NULL; 1562 } else { 1563 u8 *data = skb->data; 1564 size_t len = skb_headlen(skb); 1565 skb->data -= align; 1566 memmove(skb->data, data, len); 1567 skb_set_tail_pointer(skb, len); 1568 } 1569 } 1570 #endif 1571 1572 if (skb) { 1573 /* deliver to local stack */ 1574 skb->protocol = eth_type_trans(skb, dev); 1575 memset(skb->cb, 0, sizeof(skb->cb)); 1576 netif_rx(skb); 1577 } 1578 } 1579 1580 if (xmit_skb) { 1581 /* send to wireless media */ 1582 xmit_skb->protocol = htons(ETH_P_802_3); 1583 skb_reset_network_header(xmit_skb); 1584 skb_reset_mac_header(xmit_skb); 1585 dev_queue_xmit(xmit_skb); 1586 } 1587 } 1588 1589 static ieee80211_rx_result debug_noinline 1590 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1591 { 1592 struct net_device *dev = rx->sdata->dev; 1593 struct sk_buff *skb = rx->skb; 1594 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1595 __le16 fc = hdr->frame_control; 1596 struct sk_buff_head frame_list; 1597 1598 if (unlikely(!ieee80211_is_data(fc))) 1599 return RX_CONTINUE; 1600 1601 if (unlikely(!ieee80211_is_data_present(fc))) 1602 return RX_DROP_MONITOR; 1603 1604 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1605 return RX_CONTINUE; 1606 1607 if (ieee80211_has_a4(hdr->frame_control) && 1608 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1609 !rx->sdata->u.vlan.sta) 1610 return RX_DROP_UNUSABLE; 1611 1612 if (is_multicast_ether_addr(hdr->addr1) && 1613 ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1614 rx->sdata->u.vlan.sta) || 1615 (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 1616 rx->sdata->u.mgd.use_4addr))) 1617 return RX_DROP_UNUSABLE; 1618 1619 skb->dev = dev; 1620 __skb_queue_head_init(&frame_list); 1621 1622 if (skb_linearize(skb)) 1623 return RX_DROP_UNUSABLE; 1624 1625 ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, 1626 rx->sdata->vif.type, 1627 rx->local->hw.extra_tx_headroom); 1628 1629 while (!skb_queue_empty(&frame_list)) { 1630 rx->skb = __skb_dequeue(&frame_list); 1631 1632 if (!ieee80211_frame_allowed(rx, fc)) { 1633 dev_kfree_skb(rx->skb); 1634 continue; 1635 } 1636 dev->stats.rx_packets++; 1637 dev->stats.rx_bytes += rx->skb->len; 1638 1639 ieee80211_deliver_skb(rx); 1640 } 1641 1642 return RX_QUEUED; 1643 } 1644 1645 #ifdef CONFIG_MAC80211_MESH 1646 static ieee80211_rx_result 1647 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1648 { 1649 struct ieee80211_hdr *hdr; 1650 struct ieee80211s_hdr *mesh_hdr; 1651 unsigned int hdrlen; 1652 struct sk_buff *skb = rx->skb, *fwd_skb; 1653 struct ieee80211_local *local = rx->local; 1654 struct ieee80211_sub_if_data *sdata = rx->sdata; 1655 1656 hdr = (struct ieee80211_hdr *) skb->data; 1657 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1658 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1659 1660 if (!ieee80211_is_data(hdr->frame_control)) 1661 return RX_CONTINUE; 1662 1663 if (!mesh_hdr->ttl) 1664 /* illegal frame */ 1665 return RX_DROP_MONITOR; 1666 1667 if (mesh_hdr->flags & MESH_FLAGS_AE) { 1668 struct mesh_path *mppath; 1669 char *proxied_addr; 1670 char *mpp_addr; 1671 1672 if (is_multicast_ether_addr(hdr->addr1)) { 1673 mpp_addr = hdr->addr3; 1674 proxied_addr = mesh_hdr->eaddr1; 1675 } else { 1676 mpp_addr = hdr->addr4; 1677 proxied_addr = mesh_hdr->eaddr2; 1678 } 1679 1680 rcu_read_lock(); 1681 mppath = mpp_path_lookup(proxied_addr, sdata); 1682 if (!mppath) { 1683 mpp_path_add(proxied_addr, mpp_addr, sdata); 1684 } else { 1685 spin_lock_bh(&mppath->state_lock); 1686 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) 1687 memcpy(mppath->mpp, mpp_addr, ETH_ALEN); 1688 spin_unlock_bh(&mppath->state_lock); 1689 } 1690 rcu_read_unlock(); 1691 } 1692 1693 /* Frame has reached destination. Don't forward */ 1694 if (!is_multicast_ether_addr(hdr->addr1) && 1695 compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) 1696 return RX_CONTINUE; 1697 1698 mesh_hdr->ttl--; 1699 1700 if (rx->flags & IEEE80211_RX_RA_MATCH) { 1701 if (!mesh_hdr->ttl) 1702 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1703 dropped_frames_ttl); 1704 else { 1705 struct ieee80211_hdr *fwd_hdr; 1706 struct ieee80211_tx_info *info; 1707 1708 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1709 1710 if (!fwd_skb && net_ratelimit()) 1711 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1712 sdata->name); 1713 1714 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1715 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); 1716 info = IEEE80211_SKB_CB(fwd_skb); 1717 memset(info, 0, sizeof(*info)); 1718 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1719 info->control.vif = &rx->sdata->vif; 1720 skb_set_queue_mapping(skb, 1721 ieee80211_select_queue(rx->sdata, fwd_skb)); 1722 ieee80211_set_qos_hdr(local, skb); 1723 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1724 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1725 fwded_mcast); 1726 else { 1727 int err; 1728 /* 1729 * Save TA to addr1 to send TA a path error if a 1730 * suitable next hop is not found 1731 */ 1732 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1733 ETH_ALEN); 1734 err = mesh_nexthop_lookup(fwd_skb, sdata); 1735 /* Failed to immediately resolve next hop: 1736 * fwded frame was dropped or will be added 1737 * later to the pending skb queue. */ 1738 if (err) 1739 return RX_DROP_MONITOR; 1740 1741 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1742 fwded_unicast); 1743 } 1744 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1745 fwded_frames); 1746 ieee80211_add_pending_skb(local, fwd_skb); 1747 } 1748 } 1749 1750 if (is_multicast_ether_addr(hdr->addr1) || 1751 sdata->dev->flags & IFF_PROMISC) 1752 return RX_CONTINUE; 1753 else 1754 return RX_DROP_MONITOR; 1755 } 1756 #endif 1757 1758 static ieee80211_rx_result debug_noinline 1759 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1760 { 1761 struct ieee80211_sub_if_data *sdata = rx->sdata; 1762 struct ieee80211_local *local = rx->local; 1763 struct net_device *dev = sdata->dev; 1764 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1765 __le16 fc = hdr->frame_control; 1766 int err; 1767 1768 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1769 return RX_CONTINUE; 1770 1771 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1772 return RX_DROP_MONITOR; 1773 1774 /* 1775 * Allow the cooked monitor interface of an AP to see 4-addr frames so 1776 * that a 4-addr station can be detected and moved into a separate VLAN 1777 */ 1778 if (ieee80211_has_a4(hdr->frame_control) && 1779 sdata->vif.type == NL80211_IFTYPE_AP) 1780 return RX_DROP_MONITOR; 1781 1782 err = __ieee80211_data_to_8023(rx); 1783 if (unlikely(err)) 1784 return RX_DROP_UNUSABLE; 1785 1786 if (!ieee80211_frame_allowed(rx, fc)) 1787 return RX_DROP_MONITOR; 1788 1789 rx->skb->dev = dev; 1790 1791 dev->stats.rx_packets++; 1792 dev->stats.rx_bytes += rx->skb->len; 1793 1794 if (ieee80211_is_data(hdr->frame_control) && 1795 !is_multicast_ether_addr(hdr->addr1) && 1796 local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) { 1797 mod_timer(&local->dynamic_ps_timer, jiffies + 1798 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1799 } 1800 1801 ieee80211_deliver_skb(rx); 1802 1803 return RX_QUEUED; 1804 } 1805 1806 static ieee80211_rx_result debug_noinline 1807 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) 1808 { 1809 struct ieee80211_local *local = rx->local; 1810 struct ieee80211_hw *hw = &local->hw; 1811 struct sk_buff *skb = rx->skb; 1812 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1813 struct tid_ampdu_rx *tid_agg_rx; 1814 u16 start_seq_num; 1815 u16 tid; 1816 1817 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1818 return RX_CONTINUE; 1819 1820 if (ieee80211_is_back_req(bar->frame_control)) { 1821 struct { 1822 __le16 control, start_seq_num; 1823 } __packed bar_data; 1824 1825 if (!rx->sta) 1826 return RX_DROP_MONITOR; 1827 1828 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control), 1829 &bar_data, sizeof(bar_data))) 1830 return RX_DROP_MONITOR; 1831 1832 spin_lock(&rx->sta->lock); 1833 tid = le16_to_cpu(bar_data.control) >> 12; 1834 if (!rx->sta->ampdu_mlme.tid_active_rx[tid]) { 1835 spin_unlock(&rx->sta->lock); 1836 return RX_DROP_MONITOR; 1837 } 1838 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; 1839 1840 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4; 1841 1842 /* reset session timer */ 1843 if (tid_agg_rx->timeout) 1844 mod_timer(&tid_agg_rx->session_timer, 1845 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1846 1847 /* release stored frames up to start of BAR */ 1848 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num, 1849 frames); 1850 kfree_skb(skb); 1851 spin_unlock(&rx->sta->lock); 1852 return RX_QUEUED; 1853 } 1854 1855 return RX_CONTINUE; 1856 } 1857 1858 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 1859 struct ieee80211_mgmt *mgmt, 1860 size_t len) 1861 { 1862 struct ieee80211_local *local = sdata->local; 1863 struct sk_buff *skb; 1864 struct ieee80211_mgmt *resp; 1865 1866 if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { 1867 /* Not to own unicast address */ 1868 return; 1869 } 1870 1871 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 1872 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 1873 /* Not from the current AP or not associated yet. */ 1874 return; 1875 } 1876 1877 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 1878 /* Too short SA Query request frame */ 1879 return; 1880 } 1881 1882 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 1883 if (skb == NULL) 1884 return; 1885 1886 skb_reserve(skb, local->hw.extra_tx_headroom); 1887 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 1888 memset(resp, 0, 24); 1889 memcpy(resp->da, mgmt->sa, ETH_ALEN); 1890 memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); 1891 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 1892 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 1893 IEEE80211_STYPE_ACTION); 1894 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 1895 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 1896 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 1897 memcpy(resp->u.action.u.sa_query.trans_id, 1898 mgmt->u.action.u.sa_query.trans_id, 1899 WLAN_SA_QUERY_TR_ID_LEN); 1900 1901 ieee80211_tx_skb(sdata, skb); 1902 } 1903 1904 static ieee80211_rx_result debug_noinline 1905 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 1906 { 1907 struct ieee80211_local *local = rx->local; 1908 struct ieee80211_sub_if_data *sdata = rx->sdata; 1909 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1910 struct sk_buff *nskb; 1911 struct ieee80211_rx_status *status; 1912 int len = rx->skb->len; 1913 1914 if (!ieee80211_is_action(mgmt->frame_control)) 1915 return RX_CONTINUE; 1916 1917 /* drop too small frames */ 1918 if (len < IEEE80211_MIN_ACTION_SIZE) 1919 return RX_DROP_UNUSABLE; 1920 1921 if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) 1922 return RX_DROP_UNUSABLE; 1923 1924 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1925 return RX_DROP_UNUSABLE; 1926 1927 if (ieee80211_drop_unencrypted_mgmt(rx)) 1928 return RX_DROP_UNUSABLE; 1929 1930 switch (mgmt->u.action.category) { 1931 case WLAN_CATEGORY_BACK: 1932 /* 1933 * The aggregation code is not prepared to handle 1934 * anything but STA/AP due to the BSSID handling; 1935 * IBSS could work in the code but isn't supported 1936 * by drivers or the standard. 1937 */ 1938 if (sdata->vif.type != NL80211_IFTYPE_STATION && 1939 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 1940 sdata->vif.type != NL80211_IFTYPE_AP) 1941 break; 1942 1943 /* verify action_code is present */ 1944 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1945 break; 1946 1947 if (sdata->vif.type == NL80211_IFTYPE_STATION) 1948 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 1949 1950 switch (mgmt->u.action.u.addba_req.action_code) { 1951 case WLAN_ACTION_ADDBA_REQ: 1952 if (len < (IEEE80211_MIN_ACTION_SIZE + 1953 sizeof(mgmt->u.action.u.addba_req))) 1954 return RX_DROP_MONITOR; 1955 ieee80211_process_addba_request(local, rx->sta, mgmt, len); 1956 goto handled; 1957 case WLAN_ACTION_ADDBA_RESP: 1958 if (len < (IEEE80211_MIN_ACTION_SIZE + 1959 sizeof(mgmt->u.action.u.addba_resp))) 1960 break; 1961 ieee80211_process_addba_resp(local, rx->sta, mgmt, len); 1962 goto handled; 1963 case WLAN_ACTION_DELBA: 1964 if (len < (IEEE80211_MIN_ACTION_SIZE + 1965 sizeof(mgmt->u.action.u.delba))) 1966 break; 1967 ieee80211_process_delba(sdata, rx->sta, mgmt, len); 1968 goto handled; 1969 } 1970 break; 1971 case WLAN_CATEGORY_SPECTRUM_MGMT: 1972 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 1973 break; 1974 1975 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1976 break; 1977 1978 /* verify action_code is present */ 1979 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1980 break; 1981 1982 switch (mgmt->u.action.u.measurement.action_code) { 1983 case WLAN_ACTION_SPCT_MSR_REQ: 1984 if (len < (IEEE80211_MIN_ACTION_SIZE + 1985 sizeof(mgmt->u.action.u.measurement))) 1986 break; 1987 ieee80211_process_measurement_req(sdata, mgmt, len); 1988 goto handled; 1989 case WLAN_ACTION_SPCT_CHL_SWITCH: 1990 if (len < (IEEE80211_MIN_ACTION_SIZE + 1991 sizeof(mgmt->u.action.u.chan_switch))) 1992 break; 1993 1994 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1995 break; 1996 1997 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 1998 break; 1999 2000 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 2001 } 2002 break; 2003 case WLAN_CATEGORY_SA_QUERY: 2004 if (len < (IEEE80211_MIN_ACTION_SIZE + 2005 sizeof(mgmt->u.action.u.sa_query))) 2006 break; 2007 2008 switch (mgmt->u.action.u.sa_query.action) { 2009 case WLAN_ACTION_SA_QUERY_REQUEST: 2010 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2011 break; 2012 ieee80211_process_sa_query_req(sdata, mgmt, len); 2013 goto handled; 2014 } 2015 break; 2016 case WLAN_CATEGORY_MESH_PLINK: 2017 case WLAN_CATEGORY_MESH_PATH_SEL: 2018 if (ieee80211_vif_is_mesh(&sdata->vif)) 2019 return ieee80211_mesh_rx_mgmt(sdata, rx->skb); 2020 break; 2021 } 2022 2023 /* 2024 * For AP mode, hostapd is responsible for handling any action 2025 * frames that we didn't handle, including returning unknown 2026 * ones. For all other modes we will return them to the sender, 2027 * setting the 0x80 bit in the action category, as required by 2028 * 802.11-2007 7.3.1.11. 2029 */ 2030 if (sdata->vif.type == NL80211_IFTYPE_AP || 2031 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2032 return RX_DROP_MONITOR; 2033 2034 /* 2035 * Getting here means the kernel doesn't know how to handle 2036 * it, but maybe userspace does ... include returned frames 2037 * so userspace can register for those to know whether ones 2038 * it transmitted were processed or returned. 2039 */ 2040 status = IEEE80211_SKB_RXCB(rx->skb); 2041 2042 if (sdata->vif.type == NL80211_IFTYPE_STATION && 2043 cfg80211_rx_action(rx->sdata->dev, status->freq, 2044 rx->skb->data, rx->skb->len, 2045 GFP_ATOMIC)) 2046 goto handled; 2047 2048 /* do not return rejected action frames */ 2049 if (mgmt->u.action.category & 0x80) 2050 return RX_DROP_UNUSABLE; 2051 2052 nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0, 2053 GFP_ATOMIC); 2054 if (nskb) { 2055 struct ieee80211_mgmt *mgmt = (void *)nskb->data; 2056 2057 mgmt->u.action.category |= 0x80; 2058 memcpy(mgmt->da, mgmt->sa, ETH_ALEN); 2059 memcpy(mgmt->sa, rx->sdata->vif.addr, ETH_ALEN); 2060 2061 memset(nskb->cb, 0, sizeof(nskb->cb)); 2062 2063 ieee80211_tx_skb(rx->sdata, nskb); 2064 } 2065 2066 handled: 2067 if (rx->sta) 2068 rx->sta->rx_packets++; 2069 dev_kfree_skb(rx->skb); 2070 return RX_QUEUED; 2071 } 2072 2073 static ieee80211_rx_result debug_noinline 2074 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 2075 { 2076 struct ieee80211_sub_if_data *sdata = rx->sdata; 2077 ieee80211_rx_result rxs; 2078 2079 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 2080 return RX_DROP_MONITOR; 2081 2082 if (ieee80211_drop_unencrypted_mgmt(rx)) 2083 return RX_DROP_UNUSABLE; 2084 2085 rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); 2086 if (rxs != RX_CONTINUE) 2087 return rxs; 2088 2089 if (ieee80211_vif_is_mesh(&sdata->vif)) 2090 return ieee80211_mesh_rx_mgmt(sdata, rx->skb); 2091 2092 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 2093 return ieee80211_ibss_rx_mgmt(sdata, rx->skb); 2094 2095 if (sdata->vif.type == NL80211_IFTYPE_STATION) 2096 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 2097 2098 return RX_DROP_MONITOR; 2099 } 2100 2101 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 2102 struct ieee80211_rx_data *rx) 2103 { 2104 int keyidx; 2105 unsigned int hdrlen; 2106 2107 hdrlen = ieee80211_hdrlen(hdr->frame_control); 2108 if (rx->skb->len >= hdrlen + 4) 2109 keyidx = rx->skb->data[hdrlen + 3] >> 6; 2110 else 2111 keyidx = -1; 2112 2113 if (!rx->sta) { 2114 /* 2115 * Some hardware seem to generate incorrect Michael MIC 2116 * reports; ignore them to avoid triggering countermeasures. 2117 */ 2118 return; 2119 } 2120 2121 if (!ieee80211_has_protected(hdr->frame_control)) 2122 return; 2123 2124 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 2125 /* 2126 * APs with pairwise keys should never receive Michael MIC 2127 * errors for non-zero keyidx because these are reserved for 2128 * group keys and only the AP is sending real multicast 2129 * frames in the BSS. 2130 */ 2131 return; 2132 } 2133 2134 if (!ieee80211_is_data(hdr->frame_control) && 2135 !ieee80211_is_auth(hdr->frame_control)) 2136 return; 2137 2138 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 2139 GFP_ATOMIC); 2140 } 2141 2142 /* TODO: use IEEE80211_RX_FRAGMENTED */ 2143 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, 2144 struct ieee80211_rate *rate) 2145 { 2146 struct ieee80211_sub_if_data *sdata; 2147 struct ieee80211_local *local = rx->local; 2148 struct ieee80211_rtap_hdr { 2149 struct ieee80211_radiotap_header hdr; 2150 u8 flags; 2151 u8 rate_or_pad; 2152 __le16 chan_freq; 2153 __le16 chan_flags; 2154 } __attribute__ ((packed)) *rthdr; 2155 struct sk_buff *skb = rx->skb, *skb2; 2156 struct net_device *prev_dev = NULL; 2157 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2158 2159 if (status->flag & RX_FLAG_INTERNAL_CMTR) 2160 goto out_free_skb; 2161 2162 if (skb_headroom(skb) < sizeof(*rthdr) && 2163 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 2164 goto out_free_skb; 2165 2166 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 2167 memset(rthdr, 0, sizeof(*rthdr)); 2168 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 2169 rthdr->hdr.it_present = 2170 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 2171 (1 << IEEE80211_RADIOTAP_CHANNEL)); 2172 2173 if (rate) { 2174 rthdr->rate_or_pad = rate->bitrate / 5; 2175 rthdr->hdr.it_present |= 2176 cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 2177 } 2178 rthdr->chan_freq = cpu_to_le16(status->freq); 2179 2180 if (status->band == IEEE80211_BAND_5GHZ) 2181 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 2182 IEEE80211_CHAN_5GHZ); 2183 else 2184 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 2185 IEEE80211_CHAN_2GHZ); 2186 2187 skb_set_mac_header(skb, 0); 2188 skb->ip_summed = CHECKSUM_UNNECESSARY; 2189 skb->pkt_type = PACKET_OTHERHOST; 2190 skb->protocol = htons(ETH_P_802_2); 2191 2192 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2193 if (!ieee80211_sdata_running(sdata)) 2194 continue; 2195 2196 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 2197 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 2198 continue; 2199 2200 if (prev_dev) { 2201 skb2 = skb_clone(skb, GFP_ATOMIC); 2202 if (skb2) { 2203 skb2->dev = prev_dev; 2204 netif_rx(skb2); 2205 } 2206 } 2207 2208 prev_dev = sdata->dev; 2209 sdata->dev->stats.rx_packets++; 2210 sdata->dev->stats.rx_bytes += skb->len; 2211 } 2212 2213 if (prev_dev) { 2214 skb->dev = prev_dev; 2215 netif_rx(skb); 2216 skb = NULL; 2217 } else 2218 goto out_free_skb; 2219 2220 status->flag |= RX_FLAG_INTERNAL_CMTR; 2221 return; 2222 2223 out_free_skb: 2224 dev_kfree_skb(skb); 2225 } 2226 2227 2228 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 2229 struct ieee80211_rx_data *rx, 2230 struct sk_buff *skb, 2231 struct ieee80211_rate *rate) 2232 { 2233 struct sk_buff_head reorder_release; 2234 ieee80211_rx_result res = RX_DROP_MONITOR; 2235 2236 __skb_queue_head_init(&reorder_release); 2237 2238 rx->skb = skb; 2239 rx->sdata = sdata; 2240 2241 #define CALL_RXH(rxh) \ 2242 do { \ 2243 res = rxh(rx); \ 2244 if (res != RX_CONTINUE) \ 2245 goto rxh_next; \ 2246 } while (0); 2247 2248 /* 2249 * NB: the rxh_next label works even if we jump 2250 * to it from here because then the list will 2251 * be empty, which is a trivial check 2252 */ 2253 CALL_RXH(ieee80211_rx_h_passive_scan) 2254 CALL_RXH(ieee80211_rx_h_check) 2255 2256 ieee80211_rx_reorder_ampdu(rx, &reorder_release); 2257 2258 while ((skb = __skb_dequeue(&reorder_release))) { 2259 /* 2260 * all the other fields are valid across frames 2261 * that belong to an aMPDU since they are on the 2262 * same TID from the same station 2263 */ 2264 rx->skb = skb; 2265 2266 CALL_RXH(ieee80211_rx_h_decrypt) 2267 CALL_RXH(ieee80211_rx_h_check_more_data) 2268 CALL_RXH(ieee80211_rx_h_sta_process) 2269 CALL_RXH(ieee80211_rx_h_defragment) 2270 CALL_RXH(ieee80211_rx_h_ps_poll) 2271 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 2272 /* must be after MMIC verify so header is counted in MPDU mic */ 2273 CALL_RXH(ieee80211_rx_h_remove_qos_control) 2274 CALL_RXH(ieee80211_rx_h_amsdu) 2275 #ifdef CONFIG_MAC80211_MESH 2276 if (ieee80211_vif_is_mesh(&sdata->vif)) 2277 CALL_RXH(ieee80211_rx_h_mesh_fwding); 2278 #endif 2279 CALL_RXH(ieee80211_rx_h_data) 2280 2281 /* special treatment -- needs the queue */ 2282 res = ieee80211_rx_h_ctrl(rx, &reorder_release); 2283 if (res != RX_CONTINUE) 2284 goto rxh_next; 2285 2286 CALL_RXH(ieee80211_rx_h_action) 2287 CALL_RXH(ieee80211_rx_h_mgmt) 2288 2289 #undef CALL_RXH 2290 2291 rxh_next: 2292 switch (res) { 2293 case RX_DROP_MONITOR: 2294 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2295 if (rx->sta) 2296 rx->sta->rx_dropped++; 2297 /* fall through */ 2298 case RX_CONTINUE: 2299 ieee80211_rx_cooked_monitor(rx, rate); 2300 break; 2301 case RX_DROP_UNUSABLE: 2302 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2303 if (rx->sta) 2304 rx->sta->rx_dropped++; 2305 dev_kfree_skb(rx->skb); 2306 break; 2307 case RX_QUEUED: 2308 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 2309 break; 2310 } 2311 } 2312 } 2313 2314 /* main receive path */ 2315 2316 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 2317 struct ieee80211_rx_data *rx, 2318 struct ieee80211_hdr *hdr) 2319 { 2320 struct sk_buff *skb = rx->skb; 2321 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2322 u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 2323 int multicast = is_multicast_ether_addr(hdr->addr1); 2324 2325 switch (sdata->vif.type) { 2326 case NL80211_IFTYPE_STATION: 2327 if (!bssid && !sdata->u.mgd.use_4addr) 2328 return 0; 2329 if (!multicast && 2330 compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { 2331 if (!(sdata->dev->flags & IFF_PROMISC)) 2332 return 0; 2333 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2334 } 2335 break; 2336 case NL80211_IFTYPE_ADHOC: 2337 if (!bssid) 2338 return 0; 2339 if (ieee80211_is_beacon(hdr->frame_control)) { 2340 return 1; 2341 } 2342 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2343 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2344 return 0; 2345 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2346 } else if (!multicast && 2347 compare_ether_addr(sdata->vif.addr, 2348 hdr->addr1) != 0) { 2349 if (!(sdata->dev->flags & IFF_PROMISC)) 2350 return 0; 2351 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2352 } else if (!rx->sta) { 2353 int rate_idx; 2354 if (status->flag & RX_FLAG_HT) 2355 rate_idx = 0; /* TODO: HT rates */ 2356 else 2357 rate_idx = status->rate_idx; 2358 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, 2359 hdr->addr2, BIT(rate_idx), GFP_ATOMIC); 2360 } 2361 break; 2362 case NL80211_IFTYPE_MESH_POINT: 2363 if (!multicast && 2364 compare_ether_addr(sdata->vif.addr, 2365 hdr->addr1) != 0) { 2366 if (!(sdata->dev->flags & IFF_PROMISC)) 2367 return 0; 2368 2369 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2370 } 2371 break; 2372 case NL80211_IFTYPE_AP_VLAN: 2373 case NL80211_IFTYPE_AP: 2374 if (!bssid) { 2375 if (compare_ether_addr(sdata->vif.addr, 2376 hdr->addr1)) 2377 return 0; 2378 } else if (!ieee80211_bssid_match(bssid, 2379 sdata->vif.addr)) { 2380 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2381 return 0; 2382 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2383 } 2384 break; 2385 case NL80211_IFTYPE_WDS: 2386 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2387 return 0; 2388 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2389 return 0; 2390 break; 2391 case NL80211_IFTYPE_MONITOR: 2392 case NL80211_IFTYPE_UNSPECIFIED: 2393 case __NL80211_IFTYPE_AFTER_LAST: 2394 /* should never get here */ 2395 WARN_ON(1); 2396 break; 2397 } 2398 2399 return 1; 2400 } 2401 2402 /* 2403 * This is the actual Rx frames handler. as it blongs to Rx path it must 2404 * be called with rcu_read_lock protection. 2405 */ 2406 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2407 struct sk_buff *skb, 2408 struct ieee80211_rate *rate) 2409 { 2410 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2411 struct ieee80211_local *local = hw_to_local(hw); 2412 struct ieee80211_sub_if_data *sdata; 2413 struct ieee80211_hdr *hdr; 2414 __le16 fc; 2415 struct ieee80211_rx_data rx; 2416 int prepares; 2417 struct ieee80211_sub_if_data *prev = NULL; 2418 struct sk_buff *skb_new; 2419 struct sta_info *sta, *tmp; 2420 bool found_sta = false; 2421 int err = 0; 2422 2423 fc = ((struct ieee80211_hdr *)skb->data)->frame_control; 2424 memset(&rx, 0, sizeof(rx)); 2425 rx.skb = skb; 2426 rx.local = local; 2427 2428 if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) 2429 local->dot11ReceivedFragmentCount++; 2430 2431 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2432 test_bit(SCAN_OFF_CHANNEL, &local->scanning))) 2433 rx.flags |= IEEE80211_RX_IN_SCAN; 2434 2435 if (ieee80211_is_mgmt(fc)) 2436 err = skb_linearize(skb); 2437 else 2438 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); 2439 2440 if (err) { 2441 dev_kfree_skb(skb); 2442 return; 2443 } 2444 2445 hdr = (struct ieee80211_hdr *)skb->data; 2446 ieee80211_parse_qos(&rx); 2447 ieee80211_verify_alignment(&rx); 2448 2449 if (ieee80211_is_data(fc)) { 2450 for_each_sta_info(local, hdr->addr2, sta, tmp) { 2451 rx.sta = sta; 2452 found_sta = true; 2453 rx.sdata = sta->sdata; 2454 2455 rx.flags |= IEEE80211_RX_RA_MATCH; 2456 prepares = prepare_for_handlers(rx.sdata, &rx, hdr); 2457 if (prepares) { 2458 if (status->flag & RX_FLAG_MMIC_ERROR) { 2459 if (rx.flags & IEEE80211_RX_RA_MATCH) 2460 ieee80211_rx_michael_mic_report(hdr, &rx); 2461 } else 2462 prev = rx.sdata; 2463 } 2464 } 2465 } 2466 if (!found_sta) { 2467 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2468 if (!ieee80211_sdata_running(sdata)) 2469 continue; 2470 2471 if (sdata->vif.type == NL80211_IFTYPE_MONITOR || 2472 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2473 continue; 2474 2475 /* 2476 * frame is destined for this interface, but if it's 2477 * not also for the previous one we handle that after 2478 * the loop to avoid copying the SKB once too much 2479 */ 2480 2481 if (!prev) { 2482 prev = sdata; 2483 continue; 2484 } 2485 2486 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2487 2488 rx.flags |= IEEE80211_RX_RA_MATCH; 2489 prepares = prepare_for_handlers(prev, &rx, hdr); 2490 2491 if (!prepares) 2492 goto next; 2493 2494 if (status->flag & RX_FLAG_MMIC_ERROR) { 2495 rx.sdata = prev; 2496 if (rx.flags & IEEE80211_RX_RA_MATCH) 2497 ieee80211_rx_michael_mic_report(hdr, 2498 &rx); 2499 goto next; 2500 } 2501 2502 /* 2503 * frame was destined for the previous interface 2504 * so invoke RX handlers for it 2505 */ 2506 2507 skb_new = skb_copy(skb, GFP_ATOMIC); 2508 if (!skb_new) { 2509 if (net_ratelimit()) 2510 printk(KERN_DEBUG "%s: failed to copy " 2511 "multicast frame for %s\n", 2512 wiphy_name(local->hw.wiphy), 2513 prev->name); 2514 goto next; 2515 } 2516 ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate); 2517 next: 2518 prev = sdata; 2519 } 2520 2521 if (prev) { 2522 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2523 2524 rx.flags |= IEEE80211_RX_RA_MATCH; 2525 prepares = prepare_for_handlers(prev, &rx, hdr); 2526 2527 if (!prepares) 2528 prev = NULL; 2529 } 2530 } 2531 if (prev) 2532 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate); 2533 else 2534 dev_kfree_skb(skb); 2535 } 2536 2537 /* 2538 * This is the receive path handler. It is called by a low level driver when an 2539 * 802.11 MPDU is received from the hardware. 2540 */ 2541 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2542 { 2543 struct ieee80211_local *local = hw_to_local(hw); 2544 struct ieee80211_rate *rate = NULL; 2545 struct ieee80211_supported_band *sband; 2546 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2547 2548 WARN_ON_ONCE(softirq_count() == 0); 2549 2550 if (WARN_ON(status->band < 0 || 2551 status->band >= IEEE80211_NUM_BANDS)) 2552 goto drop; 2553 2554 sband = local->hw.wiphy->bands[status->band]; 2555 if (WARN_ON(!sband)) 2556 goto drop; 2557 2558 /* 2559 * If we're suspending, it is possible although not too likely 2560 * that we'd be receiving frames after having already partially 2561 * quiesced the stack. We can't process such frames then since 2562 * that might, for example, cause stations to be added or other 2563 * driver callbacks be invoked. 2564 */ 2565 if (unlikely(local->quiescing || local->suspended)) 2566 goto drop; 2567 2568 /* 2569 * The same happens when we're not even started, 2570 * but that's worth a warning. 2571 */ 2572 if (WARN_ON(!local->started)) 2573 goto drop; 2574 2575 if (status->flag & RX_FLAG_HT) { 2576 /* 2577 * rate_idx is MCS index, which can be [0-76] as documented on: 2578 * 2579 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n 2580 * 2581 * Anything else would be some sort of driver or hardware error. 2582 * The driver should catch hardware errors. 2583 */ 2584 if (WARN((status->rate_idx < 0 || 2585 status->rate_idx > 76), 2586 "Rate marked as an HT rate but passed " 2587 "status->rate_idx is not " 2588 "an MCS index [0-76]: %d (0x%02x)\n", 2589 status->rate_idx, 2590 status->rate_idx)) 2591 goto drop; 2592 } else { 2593 if (WARN_ON(status->rate_idx < 0 || 2594 status->rate_idx >= sband->n_bitrates)) 2595 goto drop; 2596 rate = &sband->bitrates[status->rate_idx]; 2597 } 2598 2599 /* 2600 * key references and virtual interfaces are protected using RCU 2601 * and this requires that we are in a read-side RCU section during 2602 * receive processing 2603 */ 2604 rcu_read_lock(); 2605 2606 /* 2607 * Frames with failed FCS/PLCP checksum are not returned, 2608 * all other frames are returned without radiotap header 2609 * if it was previously present. 2610 * Also, frames with less than 16 bytes are dropped. 2611 */ 2612 skb = ieee80211_rx_monitor(local, skb, rate); 2613 if (!skb) { 2614 rcu_read_unlock(); 2615 return; 2616 } 2617 2618 __ieee80211_rx_handle_packet(hw, skb, rate); 2619 2620 rcu_read_unlock(); 2621 2622 return; 2623 drop: 2624 kfree_skb(skb); 2625 } 2626 EXPORT_SYMBOL(ieee80211_rx); 2627 2628 /* This is a version of the rx handler that can be called from hard irq 2629 * context. Post the skb on the queue and schedule the tasklet */ 2630 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2631 { 2632 struct ieee80211_local *local = hw_to_local(hw); 2633 2634 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2635 2636 skb->pkt_type = IEEE80211_RX_MSG; 2637 skb_queue_tail(&local->skb_queue, skb); 2638 tasklet_schedule(&local->tasklet); 2639 } 2640 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2641