rx.c revision 34e895075e21be3e21e71d6317440d1ee7969ad0
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 "driver-ops.h" 23#include "led.h" 24#include "mesh.h" 25#include "wep.h" 26#include "wpa.h" 27#include "tkip.h" 28#include "wme.h" 29 30/* 31 * monitor mode reception 32 * 33 * This function cleans up the SKB, i.e. it removes all the stuff 34 * only useful for monitoring. 35 */ 36static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 37 struct sk_buff *skb) 38{ 39 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 40 if (likely(skb->len > FCS_LEN)) 41 skb_trim(skb, skb->len - FCS_LEN); 42 else { 43 /* driver bug */ 44 WARN_ON(1); 45 dev_kfree_skb(skb); 46 skb = NULL; 47 } 48 } 49 50 return skb; 51} 52 53static inline int should_drop_frame(struct sk_buff *skb, 54 int present_fcs_len) 55{ 56 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 57 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 58 59 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 60 return 1; 61 if (unlikely(skb->len < 16 + present_fcs_len)) 62 return 1; 63 if (ieee80211_is_ctl(hdr->frame_control) && 64 !ieee80211_is_pspoll(hdr->frame_control) && 65 !ieee80211_is_back_req(hdr->frame_control)) 66 return 1; 67 return 0; 68} 69 70static int 71ieee80211_rx_radiotap_len(struct ieee80211_local *local, 72 struct ieee80211_rx_status *status) 73{ 74 int len; 75 76 /* always present fields */ 77 len = sizeof(struct ieee80211_radiotap_header) + 9; 78 79 if (status->flag & RX_FLAG_TSFT) 80 len += 8; 81 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) 82 len += 1; 83 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) 84 len += 1; 85 86 if (len & 1) /* padding for RX_FLAGS if necessary */ 87 len++; 88 89 return len; 90} 91 92/* 93 * ieee80211_add_rx_radiotap_header - add radiotap header 94 * 95 * add a radiotap header containing all the fields which the hardware provided. 96 */ 97static void 98ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 99 struct sk_buff *skb, 100 struct ieee80211_rate *rate, 101 int rtap_len) 102{ 103 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 104 struct ieee80211_radiotap_header *rthdr; 105 unsigned char *pos; 106 u16 rx_flags = 0; 107 108 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 109 memset(rthdr, 0, rtap_len); 110 111 /* radiotap header, set always present flags */ 112 rthdr->it_present = 113 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 114 (1 << IEEE80211_RADIOTAP_CHANNEL) | 115 (1 << IEEE80211_RADIOTAP_ANTENNA) | 116 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 117 rthdr->it_len = cpu_to_le16(rtap_len); 118 119 pos = (unsigned char *)(rthdr+1); 120 121 /* the order of the following fields is important */ 122 123 /* IEEE80211_RADIOTAP_TSFT */ 124 if (status->flag & RX_FLAG_TSFT) { 125 put_unaligned_le64(status->mactime, pos); 126 rthdr->it_present |= 127 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 128 pos += 8; 129 } 130 131 /* IEEE80211_RADIOTAP_FLAGS */ 132 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 133 *pos |= IEEE80211_RADIOTAP_F_FCS; 134 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 135 *pos |= IEEE80211_RADIOTAP_F_BADFCS; 136 if (status->flag & RX_FLAG_SHORTPRE) 137 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; 138 pos++; 139 140 /* IEEE80211_RADIOTAP_RATE */ 141 if (status->flag & RX_FLAG_HT) { 142 /* 143 * TODO: add following information into radiotap header once 144 * suitable fields are defined for it: 145 * - MCS index (status->rate_idx) 146 * - HT40 (status->flag & RX_FLAG_40MHZ) 147 * - short-GI (status->flag & RX_FLAG_SHORT_GI) 148 */ 149 *pos = 0; 150 } else { 151 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 152 *pos = rate->bitrate / 5; 153 } 154 pos++; 155 156 /* IEEE80211_RADIOTAP_CHANNEL */ 157 put_unaligned_le16(status->freq, pos); 158 pos += 2; 159 if (status->band == IEEE80211_BAND_5GHZ) 160 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ, 161 pos); 162 else if (status->flag & RX_FLAG_HT) 163 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ, 164 pos); 165 else if (rate->flags & IEEE80211_RATE_ERP_G) 166 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ, 167 pos); 168 else 169 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ, 170 pos); 171 pos += 2; 172 173 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ 174 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { 175 *pos = status->signal; 176 rthdr->it_present |= 177 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); 178 pos++; 179 } 180 181 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */ 182 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) { 183 *pos = status->noise; 184 rthdr->it_present |= 185 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE); 186 pos++; 187 } 188 189 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ 190 191 /* IEEE80211_RADIOTAP_ANTENNA */ 192 *pos = status->antenna; 193 pos++; 194 195 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ 196 197 /* IEEE80211_RADIOTAP_RX_FLAGS */ 198 /* ensure 2 byte alignment for the 2 byte field as required */ 199 if ((pos - (u8 *)rthdr) & 1) 200 pos++; 201 if (status->flag & RX_FLAG_FAILED_PLCP_CRC) 202 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP; 203 put_unaligned_le16(rx_flags, pos); 204 pos += 2; 205} 206 207/* 208 * This function copies a received frame to all monitor interfaces and 209 * returns a cleaned-up SKB that no longer includes the FCS nor the 210 * radiotap header the driver might have added. 211 */ 212static struct sk_buff * 213ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 214 struct ieee80211_rate *rate) 215{ 216 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); 217 struct ieee80211_sub_if_data *sdata; 218 int needed_headroom = 0; 219 struct sk_buff *skb, *skb2; 220 struct net_device *prev_dev = NULL; 221 int present_fcs_len = 0; 222 223 /* 224 * First, we may need to make a copy of the skb because 225 * (1) we need to modify it for radiotap (if not present), and 226 * (2) the other RX handlers will modify the skb we got. 227 * 228 * We don't need to, of course, if we aren't going to return 229 * the SKB because it has a bad FCS/PLCP checksum. 230 */ 231 232 /* room for the radiotap header based on driver features */ 233 needed_headroom = ieee80211_rx_radiotap_len(local, status); 234 235 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 236 present_fcs_len = FCS_LEN; 237 238 if (!local->monitors) { 239 if (should_drop_frame(origskb, present_fcs_len)) { 240 dev_kfree_skb(origskb); 241 return NULL; 242 } 243 244 return remove_monitor_info(local, origskb); 245 } 246 247 if (should_drop_frame(origskb, present_fcs_len)) { 248 /* only need to expand headroom if necessary */ 249 skb = origskb; 250 origskb = NULL; 251 252 /* 253 * This shouldn't trigger often because most devices have an 254 * RX header they pull before we get here, and that should 255 * be big enough for our radiotap information. We should 256 * probably export the length to drivers so that we can have 257 * them allocate enough headroom to start with. 258 */ 259 if (skb_headroom(skb) < needed_headroom && 260 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) { 261 dev_kfree_skb(skb); 262 return NULL; 263 } 264 } else { 265 /* 266 * Need to make a copy and possibly remove radiotap header 267 * and FCS from the original. 268 */ 269 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 270 271 origskb = remove_monitor_info(local, origskb); 272 273 if (!skb) 274 return origskb; 275 } 276 277 /* prepend radiotap information */ 278 ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom); 279 280 skb_reset_mac_header(skb); 281 skb->ip_summed = CHECKSUM_UNNECESSARY; 282 skb->pkt_type = PACKET_OTHERHOST; 283 skb->protocol = htons(ETH_P_802_2); 284 285 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 286 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) 287 continue; 288 289 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 290 continue; 291 292 if (!ieee80211_sdata_running(sdata)) 293 continue; 294 295 if (prev_dev) { 296 skb2 = skb_clone(skb, GFP_ATOMIC); 297 if (skb2) { 298 skb2->dev = prev_dev; 299 netif_rx(skb2); 300 } 301 } 302 303 prev_dev = sdata->dev; 304 sdata->dev->stats.rx_packets++; 305 sdata->dev->stats.rx_bytes += skb->len; 306 } 307 308 if (prev_dev) { 309 skb->dev = prev_dev; 310 netif_rx(skb); 311 } else 312 dev_kfree_skb(skb); 313 314 return origskb; 315} 316 317 318static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 319{ 320 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 321 int tid; 322 323 /* does the frame have a qos control field? */ 324 if (ieee80211_is_data_qos(hdr->frame_control)) { 325 u8 *qc = ieee80211_get_qos_ctl(hdr); 326 /* frame has qos control */ 327 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 328 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 329 rx->flags |= IEEE80211_RX_AMSDU; 330 else 331 rx->flags &= ~IEEE80211_RX_AMSDU; 332 } else { 333 /* 334 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 335 * 336 * Sequence numbers for management frames, QoS data 337 * frames with a broadcast/multicast address in the 338 * Address 1 field, and all non-QoS data frames sent 339 * by QoS STAs are assigned using an additional single 340 * modulo-4096 counter, [...] 341 * 342 * We also use that counter for non-QoS STAs. 343 */ 344 tid = NUM_RX_DATA_QUEUES - 1; 345 } 346 347 rx->queue = tid; 348 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 349 * For now, set skb->priority to 0 for other cases. */ 350 rx->skb->priority = (tid > 7) ? 0 : tid; 351} 352 353/** 354 * DOC: Packet alignment 355 * 356 * Drivers always need to pass packets that are aligned to two-byte boundaries 357 * to the stack. 358 * 359 * Additionally, should, if possible, align the payload data in a way that 360 * guarantees that the contained IP header is aligned to a four-byte 361 * boundary. In the case of regular frames, this simply means aligning the 362 * payload to a four-byte boundary (because either the IP header is directly 363 * contained, or IV/RFC1042 headers that have a length divisible by four are 364 * in front of it). If the payload data is not properly aligned and the 365 * architecture doesn't support efficient unaligned operations, mac80211 366 * will align the data. 367 * 368 * With A-MSDU frames, however, the payload data address must yield two modulo 369 * four because there are 14-byte 802.3 headers within the A-MSDU frames that 370 * push the IP header further back to a multiple of four again. Thankfully, the 371 * specs were sane enough this time around to require padding each A-MSDU 372 * subframe to a length that is a multiple of four. 373 * 374 * Padding like Atheros hardware adds which is inbetween the 802.11 header and 375 * the payload is not supported, the driver is required to move the 802.11 376 * header to be directly in front of the payload in that case. 377 */ 378static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) 379{ 380#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 381 WARN_ONCE((unsigned long)rx->skb->data & 1, 382 "unaligned packet at 0x%p\n", rx->skb->data); 383#endif 384} 385 386 387/* rx handlers */ 388 389static ieee80211_rx_result debug_noinline 390ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 391{ 392 struct ieee80211_local *local = rx->local; 393 struct sk_buff *skb = rx->skb; 394 395 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning))) 396 return ieee80211_scan_rx(rx->sdata, skb); 397 398 if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) && 399 (rx->flags & IEEE80211_RX_IN_SCAN))) { 400 /* drop all the other packets during a software scan anyway */ 401 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED) 402 dev_kfree_skb(skb); 403 return RX_QUEUED; 404 } 405 406 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { 407 /* scanning finished during invoking of handlers */ 408 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 409 return RX_DROP_UNUSABLE; 410 } 411 412 return RX_CONTINUE; 413} 414 415 416static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) 417{ 418 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 419 420 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) 421 return 0; 422 423 return ieee80211_is_robust_mgmt_frame(hdr); 424} 425 426 427static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) 428{ 429 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 430 431 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) 432 return 0; 433 434 return ieee80211_is_robust_mgmt_frame(hdr); 435} 436 437 438/* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ 439static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) 440{ 441 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; 442 struct ieee80211_mmie *mmie; 443 444 if (skb->len < 24 + sizeof(*mmie) || 445 !is_multicast_ether_addr(hdr->da)) 446 return -1; 447 448 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) 449 return -1; /* not a robust management frame */ 450 451 mmie = (struct ieee80211_mmie *) 452 (skb->data + skb->len - sizeof(*mmie)); 453 if (mmie->element_id != WLAN_EID_MMIE || 454 mmie->length != sizeof(*mmie) - 2) 455 return -1; 456 457 return le16_to_cpu(mmie->key_id); 458} 459 460 461static ieee80211_rx_result 462ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 463{ 464 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 465 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 466 char *dev_addr = rx->sdata->vif.addr; 467 468 if (ieee80211_is_data(hdr->frame_control)) { 469 if (is_multicast_ether_addr(hdr->addr1)) { 470 if (ieee80211_has_tods(hdr->frame_control) || 471 !ieee80211_has_fromds(hdr->frame_control)) 472 return RX_DROP_MONITOR; 473 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0) 474 return RX_DROP_MONITOR; 475 } else { 476 if (!ieee80211_has_a4(hdr->frame_control)) 477 return RX_DROP_MONITOR; 478 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0) 479 return RX_DROP_MONITOR; 480 } 481 } 482 483 /* If there is not an established peer link and this is not a peer link 484 * establisment frame, beacon or probe, drop the frame. 485 */ 486 487 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 488 struct ieee80211_mgmt *mgmt; 489 490 if (!ieee80211_is_mgmt(hdr->frame_control)) 491 return RX_DROP_MONITOR; 492 493 if (ieee80211_is_action(hdr->frame_control)) { 494 mgmt = (struct ieee80211_mgmt *)hdr; 495 if (mgmt->u.action.category != MESH_PLINK_CATEGORY) 496 return RX_DROP_MONITOR; 497 return RX_CONTINUE; 498 } 499 500 if (ieee80211_is_probe_req(hdr->frame_control) || 501 ieee80211_is_probe_resp(hdr->frame_control) || 502 ieee80211_is_beacon(hdr->frame_control)) 503 return RX_CONTINUE; 504 505 return RX_DROP_MONITOR; 506 507 } 508 509#define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 510 511 if (ieee80211_is_data(hdr->frame_control) && 512 is_multicast_ether_addr(hdr->addr1) && 513 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata)) 514 return RX_DROP_MONITOR; 515#undef msh_h_get 516 517 return RX_CONTINUE; 518} 519 520#define SEQ_MODULO 0x1000 521#define SEQ_MASK 0xfff 522 523static inline int seq_less(u16 sq1, u16 sq2) 524{ 525 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); 526} 527 528static inline u16 seq_inc(u16 sq) 529{ 530 return (sq + 1) & SEQ_MASK; 531} 532 533static inline u16 seq_sub(u16 sq1, u16 sq2) 534{ 535 return (sq1 - sq2) & SEQ_MASK; 536} 537 538 539static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, 540 struct tid_ampdu_rx *tid_agg_rx, 541 int index, 542 struct sk_buff_head *frames) 543{ 544 struct ieee80211_supported_band *sband; 545 struct ieee80211_rate *rate = NULL; 546 struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; 547 struct ieee80211_rx_status *status; 548 549 if (!skb) 550 goto no_frame; 551 552 status = IEEE80211_SKB_RXCB(skb); 553 554 /* release the reordered frames to stack */ 555 sband = hw->wiphy->bands[status->band]; 556 if (!(status->flag & RX_FLAG_HT)) 557 rate = &sband->bitrates[status->rate_idx]; 558 tid_agg_rx->stored_mpdu_num--; 559 tid_agg_rx->reorder_buf[index] = NULL; 560 __skb_queue_tail(frames, skb); 561 562no_frame: 563 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 564} 565 566static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw, 567 struct tid_ampdu_rx *tid_agg_rx, 568 u16 head_seq_num, 569 struct sk_buff_head *frames) 570{ 571 int index; 572 573 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 574 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 575 tid_agg_rx->buf_size; 576 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); 577 } 578} 579 580/* 581 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If 582 * the skb was added to the buffer longer than this time ago, the earlier 583 * frames that have not yet been received are assumed to be lost and the skb 584 * can be released for processing. This may also release other skb's from the 585 * reorder buffer if there are no additional gaps between the frames. 586 */ 587#define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) 588 589/* 590 * As this function belongs to the RX path it must be under 591 * rcu_read_lock protection. It returns false if the frame 592 * can be processed immediately, true if it was consumed. 593 */ 594static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 595 struct tid_ampdu_rx *tid_agg_rx, 596 struct sk_buff *skb, 597 struct sk_buff_head *frames) 598{ 599 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 600 u16 sc = le16_to_cpu(hdr->seq_ctrl); 601 u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 602 u16 head_seq_num, buf_size; 603 int index; 604 605 buf_size = tid_agg_rx->buf_size; 606 head_seq_num = tid_agg_rx->head_seq_num; 607 608 /* frame with out of date sequence number */ 609 if (seq_less(mpdu_seq_num, head_seq_num)) { 610 dev_kfree_skb(skb); 611 return true; 612 } 613 614 /* 615 * If frame the sequence number exceeds our buffering window 616 * size release some previous frames to make room for this one. 617 */ 618 if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) { 619 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size)); 620 /* release stored frames up to new head to stack */ 621 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num, 622 frames); 623 } 624 625 /* Now the new frame is always in the range of the reordering buffer */ 626 627 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; 628 629 /* check if we already stored this frame */ 630 if (tid_agg_rx->reorder_buf[index]) { 631 dev_kfree_skb(skb); 632 return true; 633 } 634 635 /* 636 * If the current MPDU is in the right order and nothing else 637 * is stored we can process it directly, no need to buffer it. 638 */ 639 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 640 tid_agg_rx->stored_mpdu_num == 0) { 641 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 642 return false; 643 } 644 645 /* put the frame in the reordering buffer */ 646 tid_agg_rx->reorder_buf[index] = skb; 647 tid_agg_rx->reorder_time[index] = jiffies; 648 tid_agg_rx->stored_mpdu_num++; 649 /* release the buffer until next missing frame */ 650 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 651 tid_agg_rx->buf_size; 652 if (!tid_agg_rx->reorder_buf[index] && 653 tid_agg_rx->stored_mpdu_num > 1) { 654 /* 655 * No buffers ready to be released, but check whether any 656 * frames in the reorder buffer have timed out. 657 */ 658 int j; 659 int skipped = 1; 660 for (j = (index + 1) % tid_agg_rx->buf_size; j != index; 661 j = (j + 1) % tid_agg_rx->buf_size) { 662 if (!tid_agg_rx->reorder_buf[j]) { 663 skipped++; 664 continue; 665 } 666 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + 667 HT_RX_REORDER_BUF_TIMEOUT)) 668 break; 669 670#ifdef CONFIG_MAC80211_HT_DEBUG 671 if (net_ratelimit()) 672 printk(KERN_DEBUG "%s: release an RX reorder " 673 "frame due to timeout on earlier " 674 "frames\n", 675 wiphy_name(hw->wiphy)); 676#endif 677 ieee80211_release_reorder_frame(hw, tid_agg_rx, 678 j, frames); 679 680 /* 681 * Increment the head seq# also for the skipped slots. 682 */ 683 tid_agg_rx->head_seq_num = 684 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK; 685 skipped = 0; 686 } 687 } else while (tid_agg_rx->reorder_buf[index]) { 688 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames); 689 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 690 tid_agg_rx->buf_size; 691 } 692 693 return true; 694} 695 696/* 697 * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns 698 * true if the MPDU was buffered, false if it should be processed. 699 */ 700static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx, 701 struct sk_buff_head *frames) 702{ 703 struct sk_buff *skb = rx->skb; 704 struct ieee80211_local *local = rx->local; 705 struct ieee80211_hw *hw = &local->hw; 706 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 707 struct sta_info *sta = rx->sta; 708 struct tid_ampdu_rx *tid_agg_rx; 709 u16 sc; 710 int tid; 711 712 if (!ieee80211_is_data_qos(hdr->frame_control)) 713 goto dont_reorder; 714 715 /* 716 * filter the QoS data rx stream according to 717 * STA/TID and check if this STA/TID is on aggregation 718 */ 719 720 if (!sta) 721 goto dont_reorder; 722 723 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 724 725 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) 726 goto dont_reorder; 727 728 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; 729 730 /* qos null data frames are excluded */ 731 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 732 goto dont_reorder; 733 734 /* new, potentially un-ordered, ampdu frame - process it */ 735 736 /* reset session timer */ 737 if (tid_agg_rx->timeout) 738 mod_timer(&tid_agg_rx->session_timer, 739 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 740 741 /* if this mpdu is fragmented - terminate rx aggregation session */ 742 sc = le16_to_cpu(hdr->seq_ctrl); 743 if (sc & IEEE80211_SCTL_FRAG) { 744 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr, 745 tid, 0, 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 return; 752 753 dont_reorder: 754 __skb_queue_tail(frames, skb); 755} 756 757static ieee80211_rx_result debug_noinline 758ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 759{ 760 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 761 762 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 763 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 764 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 765 rx->sta->last_seq_ctrl[rx->queue] == 766 hdr->seq_ctrl)) { 767 if (rx->flags & IEEE80211_RX_RA_MATCH) { 768 rx->local->dot11FrameDuplicateCount++; 769 rx->sta->num_duplicates++; 770 } 771 return RX_DROP_MONITOR; 772 } else 773 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 774 } 775 776 if (unlikely(rx->skb->len < 16)) { 777 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 778 return RX_DROP_MONITOR; 779 } 780 781 /* Drop disallowed frame classes based on STA auth/assoc state; 782 * IEEE 802.11, Chap 5.5. 783 * 784 * mac80211 filters only based on association state, i.e. it drops 785 * Class 3 frames from not associated stations. hostapd sends 786 * deauth/disassoc frames when needed. In addition, hostapd is 787 * responsible for filtering on both auth and assoc states. 788 */ 789 790 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 791 return ieee80211_rx_mesh_check(rx); 792 793 if (unlikely((ieee80211_is_data(hdr->frame_control) || 794 ieee80211_is_pspoll(hdr->frame_control)) && 795 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 796 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 797 if ((!ieee80211_has_fromds(hdr->frame_control) && 798 !ieee80211_has_tods(hdr->frame_control) && 799 ieee80211_is_data(hdr->frame_control)) || 800 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 801 /* Drop IBSS frames and frames for other hosts 802 * silently. */ 803 return RX_DROP_MONITOR; 804 } 805 806 return RX_DROP_MONITOR; 807 } 808 809 return RX_CONTINUE; 810} 811 812 813static ieee80211_rx_result debug_noinline 814ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 815{ 816 struct sk_buff *skb = rx->skb; 817 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 818 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 819 int keyidx; 820 int hdrlen; 821 ieee80211_rx_result result = RX_DROP_UNUSABLE; 822 struct ieee80211_key *stakey = NULL; 823 int mmie_keyidx = -1; 824 825 /* 826 * Key selection 101 827 * 828 * There are four types of keys: 829 * - GTK (group keys) 830 * - IGTK (group keys for management frames) 831 * - PTK (pairwise keys) 832 * - STK (station-to-station pairwise keys) 833 * 834 * When selecting a key, we have to distinguish between multicast 835 * (including broadcast) and unicast frames, the latter can only 836 * use PTKs and STKs while the former always use GTKs and IGTKs. 837 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 838 * unicast frames can also use key indices like GTKs. Hence, if we 839 * don't have a PTK/STK we check the key index for a WEP key. 840 * 841 * Note that in a regular BSS, multicast frames are sent by the 842 * AP only, associated stations unicast the frame to the AP first 843 * which then multicasts it on their behalf. 844 * 845 * There is also a slight problem in IBSS mode: GTKs are negotiated 846 * with each station, that is something we don't currently handle. 847 * The spec seems to expect that one negotiates the same key with 848 * every station but there's no such requirement; VLANs could be 849 * possible. 850 */ 851 852 /* 853 * No point in finding a key and decrypting if the frame is neither 854 * addressed to us nor a multicast frame. 855 */ 856 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 857 return RX_CONTINUE; 858 859 /* start without a key */ 860 rx->key = NULL; 861 862 if (rx->sta) 863 stakey = rcu_dereference(rx->sta->key); 864 865 if (!ieee80211_has_protected(hdr->frame_control)) 866 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 867 868 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 869 rx->key = stakey; 870 /* Skip decryption if the frame is not protected. */ 871 if (!ieee80211_has_protected(hdr->frame_control)) 872 return RX_CONTINUE; 873 } else if (mmie_keyidx >= 0) { 874 /* Broadcast/multicast robust management frame / BIP */ 875 if ((status->flag & RX_FLAG_DECRYPTED) && 876 (status->flag & RX_FLAG_IV_STRIPPED)) 877 return RX_CONTINUE; 878 879 if (mmie_keyidx < NUM_DEFAULT_KEYS || 880 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 881 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 882 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 883 } else if (!ieee80211_has_protected(hdr->frame_control)) { 884 /* 885 * The frame was not protected, so skip decryption. However, we 886 * need to set rx->key if there is a key that could have been 887 * used so that the frame may be dropped if encryption would 888 * have been expected. 889 */ 890 struct ieee80211_key *key = NULL; 891 if (ieee80211_is_mgmt(hdr->frame_control) && 892 is_multicast_ether_addr(hdr->addr1) && 893 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 894 rx->key = key; 895 else if ((key = rcu_dereference(rx->sdata->default_key))) 896 rx->key = key; 897 return RX_CONTINUE; 898 } else { 899 /* 900 * The device doesn't give us the IV so we won't be 901 * able to look up the key. That's ok though, we 902 * don't need to decrypt the frame, we just won't 903 * be able to keep statistics accurate. 904 * Except for key threshold notifications, should 905 * we somehow allow the driver to tell us which key 906 * the hardware used if this flag is set? 907 */ 908 if ((status->flag & RX_FLAG_DECRYPTED) && 909 (status->flag & RX_FLAG_IV_STRIPPED)) 910 return RX_CONTINUE; 911 912 hdrlen = ieee80211_hdrlen(hdr->frame_control); 913 914 if (rx->skb->len < 8 + hdrlen) 915 return RX_DROP_UNUSABLE; /* TODO: count this? */ 916 917 /* 918 * no need to call ieee80211_wep_get_keyidx, 919 * it verifies a bunch of things we've done already 920 */ 921 keyidx = rx->skb->data[hdrlen + 3] >> 6; 922 923 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 924 925 /* 926 * RSNA-protected unicast frames should always be sent with 927 * pairwise or station-to-station keys, but for WEP we allow 928 * using a key index as well. 929 */ 930 if (rx->key && rx->key->conf.alg != ALG_WEP && 931 !is_multicast_ether_addr(hdr->addr1)) 932 rx->key = NULL; 933 } 934 935 if (rx->key) { 936 rx->key->tx_rx_count++; 937 /* TODO: add threshold stuff again */ 938 } else { 939 return RX_DROP_MONITOR; 940 } 941 942 /* Check for weak IVs if possible */ 943 if (rx->sta && rx->key->conf.alg == ALG_WEP && 944 ieee80211_is_data(hdr->frame_control) && 945 (!(status->flag & RX_FLAG_IV_STRIPPED) || 946 !(status->flag & RX_FLAG_DECRYPTED)) && 947 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 948 rx->sta->wep_weak_iv_count++; 949 950 switch (rx->key->conf.alg) { 951 case ALG_WEP: 952 result = ieee80211_crypto_wep_decrypt(rx); 953 break; 954 case ALG_TKIP: 955 result = ieee80211_crypto_tkip_decrypt(rx); 956 break; 957 case ALG_CCMP: 958 result = ieee80211_crypto_ccmp_decrypt(rx); 959 break; 960 case ALG_AES_CMAC: 961 result = ieee80211_crypto_aes_cmac_decrypt(rx); 962 break; 963 } 964 965 /* either the frame has been decrypted or will be dropped */ 966 status->flag |= RX_FLAG_DECRYPTED; 967 968 return result; 969} 970 971static ieee80211_rx_result debug_noinline 972ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 973{ 974 struct ieee80211_local *local; 975 struct ieee80211_hdr *hdr; 976 struct sk_buff *skb; 977 978 local = rx->local; 979 skb = rx->skb; 980 hdr = (struct ieee80211_hdr *) skb->data; 981 982 if (!local->pspolling) 983 return RX_CONTINUE; 984 985 if (!ieee80211_has_fromds(hdr->frame_control)) 986 /* this is not from AP */ 987 return RX_CONTINUE; 988 989 if (!ieee80211_is_data(hdr->frame_control)) 990 return RX_CONTINUE; 991 992 if (!ieee80211_has_moredata(hdr->frame_control)) { 993 /* AP has no more frames buffered for us */ 994 local->pspolling = false; 995 return RX_CONTINUE; 996 } 997 998 /* more data bit is set, let's request a new frame from the AP */ 999 ieee80211_send_pspoll(local, rx->sdata); 1000 1001 return RX_CONTINUE; 1002} 1003 1004static void ap_sta_ps_start(struct sta_info *sta) 1005{ 1006 struct ieee80211_sub_if_data *sdata = sta->sdata; 1007 struct ieee80211_local *local = sdata->local; 1008 1009 atomic_inc(&sdata->bss->num_sta_ps); 1010 set_sta_flags(sta, WLAN_STA_PS_STA); 1011 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); 1012#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1013 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 1014 sdata->name, sta->sta.addr, sta->sta.aid); 1015#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1016} 1017 1018static void ap_sta_ps_end(struct sta_info *sta) 1019{ 1020 struct ieee80211_sub_if_data *sdata = sta->sdata; 1021 1022 atomic_dec(&sdata->bss->num_sta_ps); 1023 1024 clear_sta_flags(sta, WLAN_STA_PS_STA); 1025 1026#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1027 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 1028 sdata->name, sta->sta.addr, sta->sta.aid); 1029#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1030 1031 if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) { 1032#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1033 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", 1034 sdata->name, sta->sta.addr, sta->sta.aid); 1035#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1036 return; 1037 } 1038 1039 ieee80211_sta_ps_deliver_wakeup(sta); 1040} 1041 1042static ieee80211_rx_result debug_noinline 1043ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 1044{ 1045 struct sta_info *sta = rx->sta; 1046 struct sk_buff *skb = rx->skb; 1047 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1048 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1049 1050 if (!sta) 1051 return RX_CONTINUE; 1052 1053 /* 1054 * Update last_rx only for IBSS packets which are for the current 1055 * BSSID to avoid keeping the current IBSS network alive in cases 1056 * where other STAs start using different BSSID. 1057 */ 1058 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 1059 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 1060 NL80211_IFTYPE_ADHOC); 1061 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) 1062 sta->last_rx = jiffies; 1063 } else if (!is_multicast_ether_addr(hdr->addr1)) { 1064 /* 1065 * Mesh beacons will update last_rx when if they are found to 1066 * match the current local configuration when processed. 1067 */ 1068 sta->last_rx = jiffies; 1069 } 1070 1071 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1072 return RX_CONTINUE; 1073 1074 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 1075 ieee80211_sta_rx_notify(rx->sdata, hdr); 1076 1077 sta->rx_fragments++; 1078 sta->rx_bytes += rx->skb->len; 1079 sta->last_signal = status->signal; 1080 sta->last_noise = status->noise; 1081 1082 /* 1083 * Change STA power saving mode only at the end of a frame 1084 * exchange sequence. 1085 */ 1086 if (!ieee80211_has_morefrags(hdr->frame_control) && 1087 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1088 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 1089 if (test_sta_flags(sta, WLAN_STA_PS_STA)) { 1090 /* 1091 * Ignore doze->wake transitions that are 1092 * indicated by non-data frames, the standard 1093 * is unclear here, but for example going to 1094 * PS mode and then scanning would cause a 1095 * doze->wake transition for the probe request, 1096 * and that is clearly undesirable. 1097 */ 1098 if (ieee80211_is_data(hdr->frame_control) && 1099 !ieee80211_has_pm(hdr->frame_control)) 1100 ap_sta_ps_end(sta); 1101 } else { 1102 if (ieee80211_has_pm(hdr->frame_control)) 1103 ap_sta_ps_start(sta); 1104 } 1105 } 1106 1107 /* 1108 * Drop (qos-)data::nullfunc frames silently, since they 1109 * are used only to control station power saving mode. 1110 */ 1111 if (ieee80211_is_nullfunc(hdr->frame_control) || 1112 ieee80211_is_qos_nullfunc(hdr->frame_control)) { 1113 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 1114 1115 /* 1116 * If we receive a 4-addr nullfunc frame from a STA 1117 * that was not moved to a 4-addr STA vlan yet, drop 1118 * the frame to the monitor interface, to make sure 1119 * that hostapd sees it 1120 */ 1121 if (ieee80211_has_a4(hdr->frame_control) && 1122 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1123 (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1124 !rx->sdata->u.vlan.sta))) 1125 return RX_DROP_MONITOR; 1126 /* 1127 * Update counter and free packet here to avoid 1128 * counting this as a dropped packed. 1129 */ 1130 sta->rx_packets++; 1131 dev_kfree_skb(rx->skb); 1132 return RX_QUEUED; 1133 } 1134 1135 return RX_CONTINUE; 1136} /* ieee80211_rx_h_sta_process */ 1137 1138static inline struct ieee80211_fragment_entry * 1139ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 1140 unsigned int frag, unsigned int seq, int rx_queue, 1141 struct sk_buff **skb) 1142{ 1143 struct ieee80211_fragment_entry *entry; 1144 int idx; 1145 1146 idx = sdata->fragment_next; 1147 entry = &sdata->fragments[sdata->fragment_next++]; 1148 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 1149 sdata->fragment_next = 0; 1150 1151 if (!skb_queue_empty(&entry->skb_list)) { 1152#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1153 struct ieee80211_hdr *hdr = 1154 (struct ieee80211_hdr *) entry->skb_list.next->data; 1155 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 1156 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 1157 "addr1=%pM addr2=%pM\n", 1158 sdata->name, idx, 1159 jiffies - entry->first_frag_time, entry->seq, 1160 entry->last_frag, hdr->addr1, hdr->addr2); 1161#endif 1162 __skb_queue_purge(&entry->skb_list); 1163 } 1164 1165 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 1166 *skb = NULL; 1167 entry->first_frag_time = jiffies; 1168 entry->seq = seq; 1169 entry->rx_queue = rx_queue; 1170 entry->last_frag = frag; 1171 entry->ccmp = 0; 1172 entry->extra_len = 0; 1173 1174 return entry; 1175} 1176 1177static inline struct ieee80211_fragment_entry * 1178ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 1179 unsigned int frag, unsigned int seq, 1180 int rx_queue, struct ieee80211_hdr *hdr) 1181{ 1182 struct ieee80211_fragment_entry *entry; 1183 int i, idx; 1184 1185 idx = sdata->fragment_next; 1186 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 1187 struct ieee80211_hdr *f_hdr; 1188 1189 idx--; 1190 if (idx < 0) 1191 idx = IEEE80211_FRAGMENT_MAX - 1; 1192 1193 entry = &sdata->fragments[idx]; 1194 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 1195 entry->rx_queue != rx_queue || 1196 entry->last_frag + 1 != frag) 1197 continue; 1198 1199 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 1200 1201 /* 1202 * Check ftype and addresses are equal, else check next fragment 1203 */ 1204 if (((hdr->frame_control ^ f_hdr->frame_control) & 1205 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 1206 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 1207 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 1208 continue; 1209 1210 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 1211 __skb_queue_purge(&entry->skb_list); 1212 continue; 1213 } 1214 return entry; 1215 } 1216 1217 return NULL; 1218} 1219 1220static ieee80211_rx_result debug_noinline 1221ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 1222{ 1223 struct ieee80211_hdr *hdr; 1224 u16 sc; 1225 __le16 fc; 1226 unsigned int frag, seq; 1227 struct ieee80211_fragment_entry *entry; 1228 struct sk_buff *skb; 1229 1230 hdr = (struct ieee80211_hdr *)rx->skb->data; 1231 fc = hdr->frame_control; 1232 sc = le16_to_cpu(hdr->seq_ctrl); 1233 frag = sc & IEEE80211_SCTL_FRAG; 1234 1235 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1236 (rx->skb)->len < 24 || 1237 is_multicast_ether_addr(hdr->addr1))) { 1238 /* not fragmented */ 1239 goto out; 1240 } 1241 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1242 1243 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1244 1245 if (frag == 0) { 1246 /* This is the first fragment of a new frame. */ 1247 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1248 rx->queue, &(rx->skb)); 1249 if (rx->key && rx->key->conf.alg == ALG_CCMP && 1250 ieee80211_has_protected(fc)) { 1251 /* Store CCMP PN so that we can verify that the next 1252 * fragment has a sequential PN value. */ 1253 entry->ccmp = 1; 1254 memcpy(entry->last_pn, 1255 rx->key->u.ccmp.rx_pn[rx->queue], 1256 CCMP_PN_LEN); 1257 } 1258 return RX_QUEUED; 1259 } 1260 1261 /* This is a fragment for a frame that should already be pending in 1262 * fragment cache. Add this fragment to the end of the pending entry. 1263 */ 1264 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1265 if (!entry) { 1266 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1267 return RX_DROP_MONITOR; 1268 } 1269 1270 /* Verify that MPDUs within one MSDU have sequential PN values. 1271 * (IEEE 802.11i, 8.3.3.4.5) */ 1272 if (entry->ccmp) { 1273 int i; 1274 u8 pn[CCMP_PN_LEN], *rpn; 1275 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 1276 return RX_DROP_UNUSABLE; 1277 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1278 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1279 pn[i]++; 1280 if (pn[i]) 1281 break; 1282 } 1283 rpn = rx->key->u.ccmp.rx_pn[rx->queue]; 1284 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1285 return RX_DROP_UNUSABLE; 1286 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1287 } 1288 1289 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1290 __skb_queue_tail(&entry->skb_list, rx->skb); 1291 entry->last_frag = frag; 1292 entry->extra_len += rx->skb->len; 1293 if (ieee80211_has_morefrags(fc)) { 1294 rx->skb = NULL; 1295 return RX_QUEUED; 1296 } 1297 1298 rx->skb = __skb_dequeue(&entry->skb_list); 1299 if (skb_tailroom(rx->skb) < entry->extra_len) { 1300 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1301 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1302 GFP_ATOMIC))) { 1303 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1304 __skb_queue_purge(&entry->skb_list); 1305 return RX_DROP_UNUSABLE; 1306 } 1307 } 1308 while ((skb = __skb_dequeue(&entry->skb_list))) { 1309 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1310 dev_kfree_skb(skb); 1311 } 1312 1313 /* Complete frame has been reassembled - process it now */ 1314 rx->flags |= IEEE80211_RX_FRAGMENTED; 1315 1316 out: 1317 if (rx->sta) 1318 rx->sta->rx_packets++; 1319 if (is_multicast_ether_addr(hdr->addr1)) 1320 rx->local->dot11MulticastReceivedFrameCount++; 1321 else 1322 ieee80211_led_rx(rx->local); 1323 return RX_CONTINUE; 1324} 1325 1326static ieee80211_rx_result debug_noinline 1327ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1328{ 1329 struct ieee80211_sub_if_data *sdata = rx->sdata; 1330 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1331 1332 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1333 !(rx->flags & IEEE80211_RX_RA_MATCH))) 1334 return RX_CONTINUE; 1335 1336 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1337 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1338 return RX_DROP_UNUSABLE; 1339 1340 if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) 1341 ieee80211_sta_ps_deliver_poll_response(rx->sta); 1342 else 1343 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1344 1345 /* Free PS Poll skb here instead of returning RX_DROP that would 1346 * count as an dropped frame. */ 1347 dev_kfree_skb(rx->skb); 1348 1349 return RX_QUEUED; 1350} 1351 1352static ieee80211_rx_result debug_noinline 1353ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1354{ 1355 u8 *data = rx->skb->data; 1356 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1357 1358 if (!ieee80211_is_data_qos(hdr->frame_control)) 1359 return RX_CONTINUE; 1360 1361 /* remove the qos control field, update frame type and meta-data */ 1362 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1363 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1364 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1365 /* change frame type to non QOS */ 1366 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1367 1368 return RX_CONTINUE; 1369} 1370 1371static int 1372ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1373{ 1374 if (unlikely(!rx->sta || 1375 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1376 return -EACCES; 1377 1378 return 0; 1379} 1380 1381static int 1382ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1383{ 1384 struct sk_buff *skb = rx->skb; 1385 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1386 1387 /* 1388 * Pass through unencrypted frames if the hardware has 1389 * decrypted them already. 1390 */ 1391 if (status->flag & RX_FLAG_DECRYPTED) 1392 return 0; 1393 1394 /* Drop unencrypted frames if key is set. */ 1395 if (unlikely(!ieee80211_has_protected(fc) && 1396 !ieee80211_is_nullfunc(fc) && 1397 ieee80211_is_data(fc) && 1398 (rx->key || rx->sdata->drop_unencrypted))) 1399 return -EACCES; 1400 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1401 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1402 rx->key)) 1403 return -EACCES; 1404 /* BIP does not use Protected field, so need to check MMIE */ 1405 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && 1406 ieee80211_get_mmie_keyidx(rx->skb) < 0 && 1407 rx->key)) 1408 return -EACCES; 1409 /* 1410 * When using MFP, Action frames are not allowed prior to 1411 * having configured keys. 1412 */ 1413 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1414 ieee80211_is_robust_mgmt_frame( 1415 (struct ieee80211_hdr *) rx->skb->data))) 1416 return -EACCES; 1417 } 1418 1419 return 0; 1420} 1421 1422static int 1423__ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1424{ 1425 struct ieee80211_sub_if_data *sdata = rx->sdata; 1426 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1427 1428 if (ieee80211_has_a4(hdr->frame_control) && 1429 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) 1430 return -1; 1431 1432 if (is_multicast_ether_addr(hdr->addr1) && 1433 ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) || 1434 (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr))) 1435 return -1; 1436 1437 return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); 1438} 1439 1440/* 1441 * requires that rx->skb is a frame with ethernet header 1442 */ 1443static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1444{ 1445 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1446 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1447 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1448 1449 /* 1450 * Allow EAPOL frames to us/the PAE group address regardless 1451 * of whether the frame was encrypted or not. 1452 */ 1453 if (ehdr->h_proto == htons(ETH_P_PAE) && 1454 (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || 1455 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1456 return true; 1457 1458 if (ieee80211_802_1x_port_control(rx) || 1459 ieee80211_drop_unencrypted(rx, fc)) 1460 return false; 1461 1462 return true; 1463} 1464 1465/* 1466 * requires that rx->skb is a frame with ethernet header 1467 */ 1468static void 1469ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1470{ 1471 struct ieee80211_sub_if_data *sdata = rx->sdata; 1472 struct net_device *dev = sdata->dev; 1473 struct sk_buff *skb, *xmit_skb; 1474 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1475 struct sta_info *dsta; 1476 1477 skb = rx->skb; 1478 xmit_skb = NULL; 1479 1480 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1481 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1482 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1483 (rx->flags & IEEE80211_RX_RA_MATCH) && 1484 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { 1485 if (is_multicast_ether_addr(ehdr->h_dest)) { 1486 /* 1487 * send multicast frames both to higher layers in 1488 * local net stack and back to the wireless medium 1489 */ 1490 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1491 if (!xmit_skb && net_ratelimit()) 1492 printk(KERN_DEBUG "%s: failed to clone " 1493 "multicast frame\n", dev->name); 1494 } else { 1495 dsta = sta_info_get(sdata, skb->data); 1496 if (dsta) { 1497 /* 1498 * The destination station is associated to 1499 * this AP (in this VLAN), so send the frame 1500 * directly to it and do not pass it to local 1501 * net stack. 1502 */ 1503 xmit_skb = skb; 1504 skb = NULL; 1505 } 1506 } 1507 } 1508 1509 if (skb) { 1510 int align __maybe_unused; 1511 1512#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1513 /* 1514 * 'align' will only take the values 0 or 2 here 1515 * since all frames are required to be aligned 1516 * to 2-byte boundaries when being passed to 1517 * mac80211. That also explains the __skb_push() 1518 * below. 1519 */ 1520 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1521 if (align) { 1522 if (WARN_ON(skb_headroom(skb) < 3)) { 1523 dev_kfree_skb(skb); 1524 skb = NULL; 1525 } else { 1526 u8 *data = skb->data; 1527 size_t len = skb_headlen(skb); 1528 skb->data -= align; 1529 memmove(skb->data, data, len); 1530 skb_set_tail_pointer(skb, len); 1531 } 1532 } 1533#endif 1534 1535 if (skb) { 1536 /* deliver to local stack */ 1537 skb->protocol = eth_type_trans(skb, dev); 1538 memset(skb->cb, 0, sizeof(skb->cb)); 1539 netif_rx(skb); 1540 } 1541 } 1542 1543 if (xmit_skb) { 1544 /* send to wireless media */ 1545 xmit_skb->protocol = htons(ETH_P_802_3); 1546 skb_reset_network_header(xmit_skb); 1547 skb_reset_mac_header(xmit_skb); 1548 dev_queue_xmit(xmit_skb); 1549 } 1550} 1551 1552static ieee80211_rx_result debug_noinline 1553ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1554{ 1555 struct net_device *dev = rx->sdata->dev; 1556 struct sk_buff *skb = rx->skb; 1557 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1558 __le16 fc = hdr->frame_control; 1559 struct sk_buff_head frame_list; 1560 1561 if (unlikely(!ieee80211_is_data(fc))) 1562 return RX_CONTINUE; 1563 1564 if (unlikely(!ieee80211_is_data_present(fc))) 1565 return RX_DROP_MONITOR; 1566 1567 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1568 return RX_CONTINUE; 1569 1570 if (ieee80211_has_a4(hdr->frame_control) && 1571 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1572 !rx->sdata->u.vlan.sta) 1573 return RX_DROP_UNUSABLE; 1574 1575 if (is_multicast_ether_addr(hdr->addr1) && 1576 ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1577 rx->sdata->u.vlan.sta) || 1578 (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 1579 rx->sdata->u.mgd.use_4addr))) 1580 return RX_DROP_UNUSABLE; 1581 1582 skb->dev = dev; 1583 __skb_queue_head_init(&frame_list); 1584 1585 ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, 1586 rx->sdata->vif.type, 1587 rx->local->hw.extra_tx_headroom); 1588 1589 while (!skb_queue_empty(&frame_list)) { 1590 rx->skb = __skb_dequeue(&frame_list); 1591 1592 if (!ieee80211_frame_allowed(rx, fc)) { 1593 dev_kfree_skb(rx->skb); 1594 continue; 1595 } 1596 dev->stats.rx_packets++; 1597 dev->stats.rx_bytes += rx->skb->len; 1598 1599 ieee80211_deliver_skb(rx); 1600 } 1601 1602 return RX_QUEUED; 1603} 1604 1605#ifdef CONFIG_MAC80211_MESH 1606static ieee80211_rx_result 1607ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1608{ 1609 struct ieee80211_hdr *hdr; 1610 struct ieee80211s_hdr *mesh_hdr; 1611 unsigned int hdrlen; 1612 struct sk_buff *skb = rx->skb, *fwd_skb; 1613 struct ieee80211_local *local = rx->local; 1614 struct ieee80211_sub_if_data *sdata = rx->sdata; 1615 1616 hdr = (struct ieee80211_hdr *) skb->data; 1617 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1618 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1619 1620 if (!ieee80211_is_data(hdr->frame_control)) 1621 return RX_CONTINUE; 1622 1623 if (!mesh_hdr->ttl) 1624 /* illegal frame */ 1625 return RX_DROP_MONITOR; 1626 1627 if (mesh_hdr->flags & MESH_FLAGS_AE) { 1628 struct mesh_path *mppath; 1629 char *proxied_addr; 1630 char *mpp_addr; 1631 1632 if (is_multicast_ether_addr(hdr->addr1)) { 1633 mpp_addr = hdr->addr3; 1634 proxied_addr = mesh_hdr->eaddr1; 1635 } else { 1636 mpp_addr = hdr->addr4; 1637 proxied_addr = mesh_hdr->eaddr2; 1638 } 1639 1640 rcu_read_lock(); 1641 mppath = mpp_path_lookup(proxied_addr, sdata); 1642 if (!mppath) { 1643 mpp_path_add(proxied_addr, mpp_addr, sdata); 1644 } else { 1645 spin_lock_bh(&mppath->state_lock); 1646 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) 1647 memcpy(mppath->mpp, mpp_addr, ETH_ALEN); 1648 spin_unlock_bh(&mppath->state_lock); 1649 } 1650 rcu_read_unlock(); 1651 } 1652 1653 /* Frame has reached destination. Don't forward */ 1654 if (!is_multicast_ether_addr(hdr->addr1) && 1655 compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) 1656 return RX_CONTINUE; 1657 1658 mesh_hdr->ttl--; 1659 1660 if (rx->flags & IEEE80211_RX_RA_MATCH) { 1661 if (!mesh_hdr->ttl) 1662 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1663 dropped_frames_ttl); 1664 else { 1665 struct ieee80211_hdr *fwd_hdr; 1666 struct ieee80211_tx_info *info; 1667 1668 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1669 1670 if (!fwd_skb && net_ratelimit()) 1671 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1672 sdata->name); 1673 1674 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1675 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); 1676 info = IEEE80211_SKB_CB(fwd_skb); 1677 memset(info, 0, sizeof(*info)); 1678 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1679 info->control.vif = &rx->sdata->vif; 1680 skb_set_queue_mapping(skb, 1681 ieee80211_select_queue(rx->sdata, fwd_skb)); 1682 ieee80211_set_qos_hdr(local, skb); 1683 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1684 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1685 fwded_mcast); 1686 else { 1687 int err; 1688 /* 1689 * Save TA to addr1 to send TA a path error if a 1690 * suitable next hop is not found 1691 */ 1692 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1693 ETH_ALEN); 1694 err = mesh_nexthop_lookup(fwd_skb, sdata); 1695 /* Failed to immediately resolve next hop: 1696 * fwded frame was dropped or will be added 1697 * later to the pending skb queue. */ 1698 if (err) 1699 return RX_DROP_MONITOR; 1700 1701 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1702 fwded_unicast); 1703 } 1704 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1705 fwded_frames); 1706 ieee80211_add_pending_skb(local, fwd_skb); 1707 } 1708 } 1709 1710 if (is_multicast_ether_addr(hdr->addr1) || 1711 sdata->dev->flags & IFF_PROMISC) 1712 return RX_CONTINUE; 1713 else 1714 return RX_DROP_MONITOR; 1715} 1716#endif 1717 1718static ieee80211_rx_result debug_noinline 1719ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1720{ 1721 struct ieee80211_sub_if_data *sdata = rx->sdata; 1722 struct net_device *dev = sdata->dev; 1723 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1724 __le16 fc = hdr->frame_control; 1725 int err; 1726 1727 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1728 return RX_CONTINUE; 1729 1730 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1731 return RX_DROP_MONITOR; 1732 1733 /* 1734 * Allow the cooked monitor interface of an AP to see 4-addr frames so 1735 * that a 4-addr station can be detected and moved into a separate VLAN 1736 */ 1737 if (ieee80211_has_a4(hdr->frame_control) && 1738 sdata->vif.type == NL80211_IFTYPE_AP) 1739 return RX_DROP_MONITOR; 1740 1741 err = __ieee80211_data_to_8023(rx); 1742 if (unlikely(err)) 1743 return RX_DROP_UNUSABLE; 1744 1745 if (!ieee80211_frame_allowed(rx, fc)) 1746 return RX_DROP_MONITOR; 1747 1748 rx->skb->dev = dev; 1749 1750 dev->stats.rx_packets++; 1751 dev->stats.rx_bytes += rx->skb->len; 1752 1753 ieee80211_deliver_skb(rx); 1754 1755 return RX_QUEUED; 1756} 1757 1758static ieee80211_rx_result debug_noinline 1759ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) 1760{ 1761 struct ieee80211_local *local = rx->local; 1762 struct ieee80211_hw *hw = &local->hw; 1763 struct sk_buff *skb = rx->skb; 1764 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1765 struct tid_ampdu_rx *tid_agg_rx; 1766 u16 start_seq_num; 1767 u16 tid; 1768 1769 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1770 return RX_CONTINUE; 1771 1772 if (ieee80211_is_back_req(bar->frame_control)) { 1773 if (!rx->sta) 1774 return RX_DROP_MONITOR; 1775 tid = le16_to_cpu(bar->control) >> 12; 1776 if (rx->sta->ampdu_mlme.tid_state_rx[tid] 1777 != HT_AGG_STATE_OPERATIONAL) 1778 return RX_DROP_MONITOR; 1779 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; 1780 1781 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4; 1782 1783 /* reset session timer */ 1784 if (tid_agg_rx->timeout) 1785 mod_timer(&tid_agg_rx->session_timer, 1786 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1787 1788 /* release stored frames up to start of BAR */ 1789 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num, 1790 frames); 1791 kfree_skb(skb); 1792 return RX_QUEUED; 1793 } 1794 1795 return RX_CONTINUE; 1796} 1797 1798static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 1799 struct ieee80211_mgmt *mgmt, 1800 size_t len) 1801{ 1802 struct ieee80211_local *local = sdata->local; 1803 struct sk_buff *skb; 1804 struct ieee80211_mgmt *resp; 1805 1806 if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { 1807 /* Not to own unicast address */ 1808 return; 1809 } 1810 1811 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 1812 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 1813 /* Not from the current AP or not associated yet. */ 1814 return; 1815 } 1816 1817 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 1818 /* Too short SA Query request frame */ 1819 return; 1820 } 1821 1822 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 1823 if (skb == NULL) 1824 return; 1825 1826 skb_reserve(skb, local->hw.extra_tx_headroom); 1827 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 1828 memset(resp, 0, 24); 1829 memcpy(resp->da, mgmt->sa, ETH_ALEN); 1830 memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); 1831 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 1832 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 1833 IEEE80211_STYPE_ACTION); 1834 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 1835 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 1836 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 1837 memcpy(resp->u.action.u.sa_query.trans_id, 1838 mgmt->u.action.u.sa_query.trans_id, 1839 WLAN_SA_QUERY_TR_ID_LEN); 1840 1841 ieee80211_tx_skb(sdata, skb); 1842} 1843 1844static ieee80211_rx_result debug_noinline 1845ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 1846{ 1847 struct ieee80211_local *local = rx->local; 1848 struct ieee80211_sub_if_data *sdata = rx->sdata; 1849 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1850 int len = rx->skb->len; 1851 1852 if (!ieee80211_is_action(mgmt->frame_control)) 1853 return RX_CONTINUE; 1854 1855 if (!rx->sta) 1856 return RX_DROP_MONITOR; 1857 1858 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1859 return RX_DROP_MONITOR; 1860 1861 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1862 return RX_DROP_MONITOR; 1863 1864 /* all categories we currently handle have action_code */ 1865 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1866 return RX_DROP_MONITOR; 1867 1868 switch (mgmt->u.action.category) { 1869 case WLAN_CATEGORY_BACK: 1870 /* 1871 * The aggregation code is not prepared to handle 1872 * anything but STA/AP due to the BSSID handling; 1873 * IBSS could work in the code but isn't supported 1874 * by drivers or the standard. 1875 */ 1876 if (sdata->vif.type != NL80211_IFTYPE_STATION && 1877 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 1878 sdata->vif.type != NL80211_IFTYPE_AP) 1879 return RX_DROP_MONITOR; 1880 1881 switch (mgmt->u.action.u.addba_req.action_code) { 1882 case WLAN_ACTION_ADDBA_REQ: 1883 if (len < (IEEE80211_MIN_ACTION_SIZE + 1884 sizeof(mgmt->u.action.u.addba_req))) 1885 return RX_DROP_MONITOR; 1886 ieee80211_process_addba_request(local, rx->sta, mgmt, len); 1887 break; 1888 case WLAN_ACTION_ADDBA_RESP: 1889 if (len < (IEEE80211_MIN_ACTION_SIZE + 1890 sizeof(mgmt->u.action.u.addba_resp))) 1891 return RX_DROP_MONITOR; 1892 ieee80211_process_addba_resp(local, rx->sta, mgmt, len); 1893 break; 1894 case WLAN_ACTION_DELBA: 1895 if (len < (IEEE80211_MIN_ACTION_SIZE + 1896 sizeof(mgmt->u.action.u.delba))) 1897 return RX_DROP_MONITOR; 1898 ieee80211_process_delba(sdata, rx->sta, mgmt, len); 1899 break; 1900 } 1901 break; 1902 case WLAN_CATEGORY_SPECTRUM_MGMT: 1903 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 1904 return RX_DROP_MONITOR; 1905 1906 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1907 return RX_DROP_MONITOR; 1908 1909 switch (mgmt->u.action.u.measurement.action_code) { 1910 case WLAN_ACTION_SPCT_MSR_REQ: 1911 if (len < (IEEE80211_MIN_ACTION_SIZE + 1912 sizeof(mgmt->u.action.u.measurement))) 1913 return RX_DROP_MONITOR; 1914 ieee80211_process_measurement_req(sdata, mgmt, len); 1915 break; 1916 case WLAN_ACTION_SPCT_CHL_SWITCH: 1917 if (len < (IEEE80211_MIN_ACTION_SIZE + 1918 sizeof(mgmt->u.action.u.chan_switch))) 1919 return RX_DROP_MONITOR; 1920 1921 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1922 return RX_DROP_MONITOR; 1923 1924 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 1925 return RX_DROP_MONITOR; 1926 1927 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 1928 } 1929 break; 1930 case WLAN_CATEGORY_SA_QUERY: 1931 if (len < (IEEE80211_MIN_ACTION_SIZE + 1932 sizeof(mgmt->u.action.u.sa_query))) 1933 return RX_DROP_MONITOR; 1934 switch (mgmt->u.action.u.sa_query.action) { 1935 case WLAN_ACTION_SA_QUERY_REQUEST: 1936 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1937 return RX_DROP_MONITOR; 1938 ieee80211_process_sa_query_req(sdata, mgmt, len); 1939 break; 1940 case WLAN_ACTION_SA_QUERY_RESPONSE: 1941 /* 1942 * SA Query response is currently only used in AP mode 1943 * and it is processed in user space. 1944 */ 1945 return RX_CONTINUE; 1946 } 1947 break; 1948 default: 1949 /* do not process rejected action frames */ 1950 if (mgmt->u.action.category & 0x80) 1951 return RX_DROP_MONITOR; 1952 1953 return RX_CONTINUE; 1954 } 1955 1956 rx->sta->rx_packets++; 1957 dev_kfree_skb(rx->skb); 1958 return RX_QUEUED; 1959} 1960 1961static ieee80211_rx_result debug_noinline 1962ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 1963{ 1964 struct ieee80211_sub_if_data *sdata = rx->sdata; 1965 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1966 ieee80211_rx_result rxs; 1967 1968 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1969 return RX_DROP_MONITOR; 1970 1971 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1972 return RX_DROP_MONITOR; 1973 1974 rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); 1975 if (rxs != RX_CONTINUE) 1976 return rxs; 1977 1978 if (ieee80211_vif_is_mesh(&sdata->vif)) 1979 return ieee80211_mesh_rx_mgmt(sdata, rx->skb); 1980 1981 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 1982 return ieee80211_ibss_rx_mgmt(sdata, rx->skb); 1983 1984 if (sdata->vif.type == NL80211_IFTYPE_STATION) 1985 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 1986 1987 return RX_DROP_MONITOR; 1988} 1989 1990static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 1991 struct ieee80211_rx_data *rx) 1992{ 1993 int keyidx; 1994 unsigned int hdrlen; 1995 1996 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1997 if (rx->skb->len >= hdrlen + 4) 1998 keyidx = rx->skb->data[hdrlen + 3] >> 6; 1999 else 2000 keyidx = -1; 2001 2002 if (!rx->sta) { 2003 /* 2004 * Some hardware seem to generate incorrect Michael MIC 2005 * reports; ignore them to avoid triggering countermeasures. 2006 */ 2007 return; 2008 } 2009 2010 if (!ieee80211_has_protected(hdr->frame_control)) 2011 return; 2012 2013 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 2014 /* 2015 * APs with pairwise keys should never receive Michael MIC 2016 * errors for non-zero keyidx because these are reserved for 2017 * group keys and only the AP is sending real multicast 2018 * frames in the BSS. 2019 */ 2020 return; 2021 } 2022 2023 if (!ieee80211_is_data(hdr->frame_control) && 2024 !ieee80211_is_auth(hdr->frame_control)) 2025 return; 2026 2027 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 2028 GFP_ATOMIC); 2029} 2030 2031/* TODO: use IEEE80211_RX_FRAGMENTED */ 2032static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, 2033 struct ieee80211_rate *rate) 2034{ 2035 struct ieee80211_sub_if_data *sdata; 2036 struct ieee80211_local *local = rx->local; 2037 struct ieee80211_rtap_hdr { 2038 struct ieee80211_radiotap_header hdr; 2039 u8 flags; 2040 u8 rate_or_pad; 2041 __le16 chan_freq; 2042 __le16 chan_flags; 2043 } __attribute__ ((packed)) *rthdr; 2044 struct sk_buff *skb = rx->skb, *skb2; 2045 struct net_device *prev_dev = NULL; 2046 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2047 2048 if (status->flag & RX_FLAG_INTERNAL_CMTR) 2049 goto out_free_skb; 2050 2051 if (skb_headroom(skb) < sizeof(*rthdr) && 2052 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 2053 goto out_free_skb; 2054 2055 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 2056 memset(rthdr, 0, sizeof(*rthdr)); 2057 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 2058 rthdr->hdr.it_present = 2059 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 2060 (1 << IEEE80211_RADIOTAP_CHANNEL)); 2061 2062 if (rate) { 2063 rthdr->rate_or_pad = rate->bitrate / 5; 2064 rthdr->hdr.it_present |= 2065 cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 2066 } 2067 rthdr->chan_freq = cpu_to_le16(status->freq); 2068 2069 if (status->band == IEEE80211_BAND_5GHZ) 2070 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 2071 IEEE80211_CHAN_5GHZ); 2072 else 2073 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 2074 IEEE80211_CHAN_2GHZ); 2075 2076 skb_set_mac_header(skb, 0); 2077 skb->ip_summed = CHECKSUM_UNNECESSARY; 2078 skb->pkt_type = PACKET_OTHERHOST; 2079 skb->protocol = htons(ETH_P_802_2); 2080 2081 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2082 if (!ieee80211_sdata_running(sdata)) 2083 continue; 2084 2085 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 2086 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 2087 continue; 2088 2089 if (prev_dev) { 2090 skb2 = skb_clone(skb, GFP_ATOMIC); 2091 if (skb2) { 2092 skb2->dev = prev_dev; 2093 netif_rx(skb2); 2094 } 2095 } 2096 2097 prev_dev = sdata->dev; 2098 sdata->dev->stats.rx_packets++; 2099 sdata->dev->stats.rx_bytes += skb->len; 2100 } 2101 2102 if (prev_dev) { 2103 skb->dev = prev_dev; 2104 netif_rx(skb); 2105 skb = NULL; 2106 } else 2107 goto out_free_skb; 2108 2109 status->flag |= RX_FLAG_INTERNAL_CMTR; 2110 return; 2111 2112 out_free_skb: 2113 dev_kfree_skb(skb); 2114} 2115 2116 2117static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 2118 struct ieee80211_rx_data *rx, 2119 struct sk_buff *skb, 2120 struct ieee80211_rate *rate) 2121{ 2122 struct sk_buff_head reorder_release; 2123 ieee80211_rx_result res = RX_DROP_MONITOR; 2124 2125 __skb_queue_head_init(&reorder_release); 2126 2127 rx->skb = skb; 2128 rx->sdata = sdata; 2129 2130#define CALL_RXH(rxh) \ 2131 do { \ 2132 res = rxh(rx); \ 2133 if (res != RX_CONTINUE) \ 2134 goto rxh_next; \ 2135 } while (0); 2136 2137 /* 2138 * NB: the rxh_next label works even if we jump 2139 * to it from here because then the list will 2140 * be empty, which is a trivial check 2141 */ 2142 CALL_RXH(ieee80211_rx_h_passive_scan) 2143 CALL_RXH(ieee80211_rx_h_check) 2144 2145 ieee80211_rx_reorder_ampdu(rx, &reorder_release); 2146 2147 while ((skb = __skb_dequeue(&reorder_release))) { 2148 /* 2149 * all the other fields are valid across frames 2150 * that belong to an aMPDU since they are on the 2151 * same TID from the same station 2152 */ 2153 rx->skb = skb; 2154 2155 CALL_RXH(ieee80211_rx_h_decrypt) 2156 CALL_RXH(ieee80211_rx_h_check_more_data) 2157 CALL_RXH(ieee80211_rx_h_sta_process) 2158 CALL_RXH(ieee80211_rx_h_defragment) 2159 CALL_RXH(ieee80211_rx_h_ps_poll) 2160 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 2161 /* must be after MMIC verify so header is counted in MPDU mic */ 2162 CALL_RXH(ieee80211_rx_h_remove_qos_control) 2163 CALL_RXH(ieee80211_rx_h_amsdu) 2164#ifdef CONFIG_MAC80211_MESH 2165 if (ieee80211_vif_is_mesh(&sdata->vif)) 2166 CALL_RXH(ieee80211_rx_h_mesh_fwding); 2167#endif 2168 CALL_RXH(ieee80211_rx_h_data) 2169 2170 /* special treatment -- needs the queue */ 2171 res = ieee80211_rx_h_ctrl(rx, &reorder_release); 2172 if (res != RX_CONTINUE) 2173 goto rxh_next; 2174 2175 CALL_RXH(ieee80211_rx_h_action) 2176 CALL_RXH(ieee80211_rx_h_mgmt) 2177 2178#undef CALL_RXH 2179 2180 rxh_next: 2181 switch (res) { 2182 case RX_DROP_MONITOR: 2183 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2184 if (rx->sta) 2185 rx->sta->rx_dropped++; 2186 /* fall through */ 2187 case RX_CONTINUE: 2188 ieee80211_rx_cooked_monitor(rx, rate); 2189 break; 2190 case RX_DROP_UNUSABLE: 2191 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2192 if (rx->sta) 2193 rx->sta->rx_dropped++; 2194 dev_kfree_skb(rx->skb); 2195 break; 2196 case RX_QUEUED: 2197 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 2198 break; 2199 } 2200 } 2201} 2202 2203/* main receive path */ 2204 2205static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 2206 struct ieee80211_rx_data *rx, 2207 struct ieee80211_hdr *hdr) 2208{ 2209 struct sk_buff *skb = rx->skb; 2210 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2211 u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 2212 int multicast = is_multicast_ether_addr(hdr->addr1); 2213 2214 switch (sdata->vif.type) { 2215 case NL80211_IFTYPE_STATION: 2216 if (!bssid && !sdata->u.mgd.use_4addr) 2217 return 0; 2218 if (!multicast && 2219 compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { 2220 if (!(sdata->dev->flags & IFF_PROMISC)) 2221 return 0; 2222 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2223 } 2224 break; 2225 case NL80211_IFTYPE_ADHOC: 2226 if (!bssid) 2227 return 0; 2228 if (ieee80211_is_beacon(hdr->frame_control)) { 2229 return 1; 2230 } 2231 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2232 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2233 return 0; 2234 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2235 } else if (!multicast && 2236 compare_ether_addr(sdata->vif.addr, 2237 hdr->addr1) != 0) { 2238 if (!(sdata->dev->flags & IFF_PROMISC)) 2239 return 0; 2240 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2241 } else if (!rx->sta) { 2242 int rate_idx; 2243 if (status->flag & RX_FLAG_HT) 2244 rate_idx = 0; /* TODO: HT rates */ 2245 else 2246 rate_idx = status->rate_idx; 2247 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, 2248 hdr->addr2, BIT(rate_idx), GFP_ATOMIC); 2249 } 2250 break; 2251 case NL80211_IFTYPE_MESH_POINT: 2252 if (!multicast && 2253 compare_ether_addr(sdata->vif.addr, 2254 hdr->addr1) != 0) { 2255 if (!(sdata->dev->flags & IFF_PROMISC)) 2256 return 0; 2257 2258 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2259 } 2260 break; 2261 case NL80211_IFTYPE_AP_VLAN: 2262 case NL80211_IFTYPE_AP: 2263 if (!bssid) { 2264 if (compare_ether_addr(sdata->vif.addr, 2265 hdr->addr1)) 2266 return 0; 2267 } else if (!ieee80211_bssid_match(bssid, 2268 sdata->vif.addr)) { 2269 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2270 return 0; 2271 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2272 } 2273 break; 2274 case NL80211_IFTYPE_WDS: 2275 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2276 return 0; 2277 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2278 return 0; 2279 break; 2280 case NL80211_IFTYPE_MONITOR: 2281 case NL80211_IFTYPE_UNSPECIFIED: 2282 case __NL80211_IFTYPE_AFTER_LAST: 2283 /* should never get here */ 2284 WARN_ON(1); 2285 break; 2286 } 2287 2288 return 1; 2289} 2290 2291/* 2292 * This is the actual Rx frames handler. as it blongs to Rx path it must 2293 * be called with rcu_read_lock protection. 2294 */ 2295static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2296 struct sk_buff *skb, 2297 struct ieee80211_rate *rate) 2298{ 2299 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2300 struct ieee80211_local *local = hw_to_local(hw); 2301 struct ieee80211_sub_if_data *sdata; 2302 struct ieee80211_hdr *hdr; 2303 struct ieee80211_rx_data rx; 2304 int prepares; 2305 struct ieee80211_sub_if_data *prev = NULL; 2306 struct sk_buff *skb_new; 2307 struct sta_info *sta, *tmp; 2308 bool found_sta = false; 2309 2310 hdr = (struct ieee80211_hdr *)skb->data; 2311 memset(&rx, 0, sizeof(rx)); 2312 rx.skb = skb; 2313 rx.local = local; 2314 2315 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control)) 2316 local->dot11ReceivedFragmentCount++; 2317 2318 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2319 test_bit(SCAN_OFF_CHANNEL, &local->scanning))) 2320 rx.flags |= IEEE80211_RX_IN_SCAN; 2321 2322 ieee80211_parse_qos(&rx); 2323 ieee80211_verify_alignment(&rx); 2324 2325 if (ieee80211_is_data(hdr->frame_control)) { 2326 for_each_sta_info(local, hdr->addr2, sta, tmp) { 2327 rx.sta = sta; 2328 found_sta = true; 2329 rx.sdata = sta->sdata; 2330 2331 rx.flags |= IEEE80211_RX_RA_MATCH; 2332 prepares = prepare_for_handlers(rx.sdata, &rx, hdr); 2333 if (prepares) { 2334 if (status->flag & RX_FLAG_MMIC_ERROR) { 2335 if (rx.flags & IEEE80211_RX_RA_MATCH) 2336 ieee80211_rx_michael_mic_report(hdr, &rx); 2337 } else 2338 prev = rx.sdata; 2339 } 2340 } 2341 } 2342 if (!found_sta) { 2343 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2344 if (!ieee80211_sdata_running(sdata)) 2345 continue; 2346 2347 if (sdata->vif.type == NL80211_IFTYPE_MONITOR || 2348 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2349 continue; 2350 2351 /* 2352 * frame is destined for this interface, but if it's 2353 * not also for the previous one we handle that after 2354 * the loop to avoid copying the SKB once too much 2355 */ 2356 2357 if (!prev) { 2358 prev = sdata; 2359 continue; 2360 } 2361 2362 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2363 2364 rx.flags |= IEEE80211_RX_RA_MATCH; 2365 prepares = prepare_for_handlers(prev, &rx, hdr); 2366 2367 if (!prepares) 2368 goto next; 2369 2370 if (status->flag & RX_FLAG_MMIC_ERROR) { 2371 rx.sdata = prev; 2372 if (rx.flags & IEEE80211_RX_RA_MATCH) 2373 ieee80211_rx_michael_mic_report(hdr, 2374 &rx); 2375 goto next; 2376 } 2377 2378 /* 2379 * frame was destined for the previous interface 2380 * so invoke RX handlers for it 2381 */ 2382 2383 skb_new = skb_copy(skb, GFP_ATOMIC); 2384 if (!skb_new) { 2385 if (net_ratelimit()) 2386 printk(KERN_DEBUG "%s: failed to copy " 2387 "multicast frame for %s\n", 2388 wiphy_name(local->hw.wiphy), 2389 prev->name); 2390 goto next; 2391 } 2392 ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate); 2393next: 2394 prev = sdata; 2395 } 2396 2397 if (prev) { 2398 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2399 2400 rx.flags |= IEEE80211_RX_RA_MATCH; 2401 prepares = prepare_for_handlers(prev, &rx, hdr); 2402 2403 if (!prepares) 2404 prev = NULL; 2405 } 2406 } 2407 if (prev) 2408 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate); 2409 else 2410 dev_kfree_skb(skb); 2411} 2412 2413/* 2414 * This is the receive path handler. It is called by a low level driver when an 2415 * 802.11 MPDU is received from the hardware. 2416 */ 2417void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2418{ 2419 struct ieee80211_local *local = hw_to_local(hw); 2420 struct ieee80211_rate *rate = NULL; 2421 struct ieee80211_supported_band *sband; 2422 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2423 2424 WARN_ON_ONCE(softirq_count() == 0); 2425 2426 if (WARN_ON(status->band < 0 || 2427 status->band >= IEEE80211_NUM_BANDS)) 2428 goto drop; 2429 2430 sband = local->hw.wiphy->bands[status->band]; 2431 if (WARN_ON(!sband)) 2432 goto drop; 2433 2434 /* 2435 * If we're suspending, it is possible although not too likely 2436 * that we'd be receiving frames after having already partially 2437 * quiesced the stack. We can't process such frames then since 2438 * that might, for example, cause stations to be added or other 2439 * driver callbacks be invoked. 2440 */ 2441 if (unlikely(local->quiescing || local->suspended)) 2442 goto drop; 2443 2444 /* 2445 * The same happens when we're not even started, 2446 * but that's worth a warning. 2447 */ 2448 if (WARN_ON(!local->started)) 2449 goto drop; 2450 2451 if (status->flag & RX_FLAG_HT) { 2452 /* 2453 * rate_idx is MCS index, which can be [0-76] as documented on: 2454 * 2455 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n 2456 * 2457 * Anything else would be some sort of driver or hardware error. 2458 * The driver should catch hardware errors. 2459 */ 2460 if (WARN((status->rate_idx < 0 || 2461 status->rate_idx > 76), 2462 "Rate marked as an HT rate but passed " 2463 "status->rate_idx is not " 2464 "an MCS index [0-76]: %d (0x%02x)\n", 2465 status->rate_idx, 2466 status->rate_idx)) 2467 goto drop; 2468 } else { 2469 if (WARN_ON(status->rate_idx < 0 || 2470 status->rate_idx >= sband->n_bitrates)) 2471 goto drop; 2472 rate = &sband->bitrates[status->rate_idx]; 2473 } 2474 2475 /* 2476 * key references and virtual interfaces are protected using RCU 2477 * and this requires that we are in a read-side RCU section during 2478 * receive processing 2479 */ 2480 rcu_read_lock(); 2481 2482 /* 2483 * Frames with failed FCS/PLCP checksum are not returned, 2484 * all other frames are returned without radiotap header 2485 * if it was previously present. 2486 * Also, frames with less than 16 bytes are dropped. 2487 */ 2488 skb = ieee80211_rx_monitor(local, skb, rate); 2489 if (!skb) { 2490 rcu_read_unlock(); 2491 return; 2492 } 2493 2494 __ieee80211_rx_handle_packet(hw, skb, rate); 2495 2496 rcu_read_unlock(); 2497 2498 return; 2499 drop: 2500 kfree_skb(skb); 2501} 2502EXPORT_SYMBOL(ieee80211_rx); 2503 2504/* This is a version of the rx handler that can be called from hard irq 2505 * context. Post the skb on the queue and schedule the tasklet */ 2506void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2507{ 2508 struct ieee80211_local *local = hw_to_local(hw); 2509 2510 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2511 2512 skb->pkt_type = IEEE80211_RX_MSG; 2513 skb_queue_tail(&local->skb_queue, skb); 2514 tasklet_schedule(&local->tasklet); 2515} 2516EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2517