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_receive_skb(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_receive_skb(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 tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 723 if (!tid_agg_rx) 724 goto dont_reorder; 725 726 /* qos null data frames are excluded */ 727 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 728 goto dont_reorder; 729 730 /* new, potentially un-ordered, ampdu frame - process it */ 731 732 /* reset session timer */ 733 if (tid_agg_rx->timeout) 734 mod_timer(&tid_agg_rx->session_timer, 735 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 736 737 /* if this mpdu is fragmented - terminate rx aggregation session */ 738 sc = le16_to_cpu(hdr->seq_ctrl); 739 if (sc & IEEE80211_SCTL_FRAG) { 740 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 741 skb_queue_tail(&rx->sdata->skb_queue, skb); 742 ieee80211_queue_work(&local->hw, &rx->sdata->work); 743 return; 744 } 745 746 /* 747 * No locking needed -- we will only ever process one 748 * RX packet at a time, and thus own tid_agg_rx. All 749 * other code manipulating it needs to (and does) make 750 * sure that we cannot get to it any more before doing 751 * anything with it. 752 */ 753 if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames)) 754 return; 755 756 dont_reorder: 757 __skb_queue_tail(frames, skb); 758 } 759 760 static ieee80211_rx_result debug_noinline 761 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 762 { 763 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 764 765 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 766 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 767 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 768 rx->sta->last_seq_ctrl[rx->queue] == 769 hdr->seq_ctrl)) { 770 if (rx->flags & IEEE80211_RX_RA_MATCH) { 771 rx->local->dot11FrameDuplicateCount++; 772 rx->sta->num_duplicates++; 773 } 774 return RX_DROP_MONITOR; 775 } else 776 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 777 } 778 779 if (unlikely(rx->skb->len < 16)) { 780 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 781 return RX_DROP_MONITOR; 782 } 783 784 /* Drop disallowed frame classes based on STA auth/assoc state; 785 * IEEE 802.11, Chap 5.5. 786 * 787 * mac80211 filters only based on association state, i.e. it drops 788 * Class 3 frames from not associated stations. hostapd sends 789 * deauth/disassoc frames when needed. In addition, hostapd is 790 * responsible for filtering on both auth and assoc states. 791 */ 792 793 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 794 return ieee80211_rx_mesh_check(rx); 795 796 if (unlikely((ieee80211_is_data(hdr->frame_control) || 797 ieee80211_is_pspoll(hdr->frame_control)) && 798 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 799 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 800 if ((!ieee80211_has_fromds(hdr->frame_control) && 801 !ieee80211_has_tods(hdr->frame_control) && 802 ieee80211_is_data(hdr->frame_control)) || 803 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 804 /* Drop IBSS frames and frames for other hosts 805 * silently. */ 806 return RX_DROP_MONITOR; 807 } 808 809 return RX_DROP_MONITOR; 810 } 811 812 return RX_CONTINUE; 813 } 814 815 816 static ieee80211_rx_result debug_noinline 817 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 818 { 819 struct sk_buff *skb = rx->skb; 820 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 821 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 822 int keyidx; 823 int hdrlen; 824 ieee80211_rx_result result = RX_DROP_UNUSABLE; 825 struct ieee80211_key *stakey = NULL; 826 int mmie_keyidx = -1; 827 __le16 fc; 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 fc = hdr->frame_control; 870 871 if (!ieee80211_has_protected(fc)) 872 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 873 874 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 875 rx->key = stakey; 876 /* Skip decryption if the frame is not protected. */ 877 if (!ieee80211_has_protected(fc)) 878 return RX_CONTINUE; 879 } else if (mmie_keyidx >= 0) { 880 /* Broadcast/multicast robust management frame / BIP */ 881 if ((status->flag & RX_FLAG_DECRYPTED) && 882 (status->flag & RX_FLAG_IV_STRIPPED)) 883 return RX_CONTINUE; 884 885 if (mmie_keyidx < NUM_DEFAULT_KEYS || 886 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 887 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 888 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 889 } else if (!ieee80211_has_protected(fc)) { 890 /* 891 * The frame was not protected, so skip decryption. However, we 892 * need to set rx->key if there is a key that could have been 893 * used so that the frame may be dropped if encryption would 894 * have been expected. 895 */ 896 struct ieee80211_key *key = NULL; 897 if (ieee80211_is_mgmt(fc) && 898 is_multicast_ether_addr(hdr->addr1) && 899 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 900 rx->key = key; 901 else if ((key = rcu_dereference(rx->sdata->default_key))) 902 rx->key = key; 903 return RX_CONTINUE; 904 } else { 905 u8 keyid; 906 /* 907 * The device doesn't give us the IV so we won't be 908 * able to look up the key. That's ok though, we 909 * don't need to decrypt the frame, we just won't 910 * be able to keep statistics accurate. 911 * Except for key threshold notifications, should 912 * we somehow allow the driver to tell us which key 913 * the hardware used if this flag is set? 914 */ 915 if ((status->flag & RX_FLAG_DECRYPTED) && 916 (status->flag & RX_FLAG_IV_STRIPPED)) 917 return RX_CONTINUE; 918 919 hdrlen = ieee80211_hdrlen(fc); 920 921 if (rx->skb->len < 8 + hdrlen) 922 return RX_DROP_UNUSABLE; /* TODO: count this? */ 923 924 /* 925 * no need to call ieee80211_wep_get_keyidx, 926 * it verifies a bunch of things we've done already 927 */ 928 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1); 929 keyidx = keyid >> 6; 930 931 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 932 933 /* 934 * RSNA-protected unicast frames should always be sent with 935 * pairwise or station-to-station keys, but for WEP we allow 936 * using a key index as well. 937 */ 938 if (rx->key && rx->key->conf.alg != ALG_WEP && 939 !is_multicast_ether_addr(hdr->addr1)) 940 rx->key = NULL; 941 } 942 943 if (rx->key) { 944 rx->key->tx_rx_count++; 945 /* TODO: add threshold stuff again */ 946 } else { 947 return RX_DROP_MONITOR; 948 } 949 950 if (skb_linearize(rx->skb)) 951 return RX_DROP_UNUSABLE; 952 /* the hdr variable is invalid now! */ 953 954 switch (rx->key->conf.alg) { 955 case ALG_WEP: 956 /* Check for weak IVs if possible */ 957 if (rx->sta && ieee80211_is_data(fc) && 958 (!(status->flag & RX_FLAG_IV_STRIPPED) || 959 !(status->flag & RX_FLAG_DECRYPTED)) && 960 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 961 rx->sta->wep_weak_iv_count++; 962 963 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 int queue = ieee80211_is_mgmt(fc) ? 1271 NUM_RX_DATA_QUEUES : rx->queue; 1272 /* Store CCMP PN so that we can verify that the next 1273 * fragment has a sequential PN value. */ 1274 entry->ccmp = 1; 1275 memcpy(entry->last_pn, 1276 rx->key->u.ccmp.rx_pn[queue], 1277 CCMP_PN_LEN); 1278 } 1279 return RX_QUEUED; 1280 } 1281 1282 /* This is a fragment for a frame that should already be pending in 1283 * fragment cache. Add this fragment to the end of the pending entry. 1284 */ 1285 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1286 if (!entry) { 1287 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1288 return RX_DROP_MONITOR; 1289 } 1290 1291 /* Verify that MPDUs within one MSDU have sequential PN values. 1292 * (IEEE 802.11i, 8.3.3.4.5) */ 1293 if (entry->ccmp) { 1294 int i; 1295 u8 pn[CCMP_PN_LEN], *rpn; 1296 int queue; 1297 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 1298 return RX_DROP_UNUSABLE; 1299 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1300 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1301 pn[i]++; 1302 if (pn[i]) 1303 break; 1304 } 1305 queue = ieee80211_is_mgmt(fc) ? 1306 NUM_RX_DATA_QUEUES : rx->queue; 1307 rpn = rx->key->u.ccmp.rx_pn[queue]; 1308 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1309 return RX_DROP_UNUSABLE; 1310 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1311 } 1312 1313 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1314 __skb_queue_tail(&entry->skb_list, rx->skb); 1315 entry->last_frag = frag; 1316 entry->extra_len += rx->skb->len; 1317 if (ieee80211_has_morefrags(fc)) { 1318 rx->skb = NULL; 1319 return RX_QUEUED; 1320 } 1321 1322 rx->skb = __skb_dequeue(&entry->skb_list); 1323 if (skb_tailroom(rx->skb) < entry->extra_len) { 1324 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1325 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1326 GFP_ATOMIC))) { 1327 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1328 __skb_queue_purge(&entry->skb_list); 1329 return RX_DROP_UNUSABLE; 1330 } 1331 } 1332 while ((skb = __skb_dequeue(&entry->skb_list))) { 1333 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1334 dev_kfree_skb(skb); 1335 } 1336 1337 /* Complete frame has been reassembled - process it now */ 1338 rx->flags |= IEEE80211_RX_FRAGMENTED; 1339 1340 out: 1341 if (rx->sta) 1342 rx->sta->rx_packets++; 1343 if (is_multicast_ether_addr(hdr->addr1)) 1344 rx->local->dot11MulticastReceivedFrameCount++; 1345 else 1346 ieee80211_led_rx(rx->local); 1347 return RX_CONTINUE; 1348 } 1349 1350 static ieee80211_rx_result debug_noinline 1351 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1352 { 1353 struct ieee80211_sub_if_data *sdata = rx->sdata; 1354 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1355 1356 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1357 !(rx->flags & IEEE80211_RX_RA_MATCH))) 1358 return RX_CONTINUE; 1359 1360 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1361 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1362 return RX_DROP_UNUSABLE; 1363 1364 if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) 1365 ieee80211_sta_ps_deliver_poll_response(rx->sta); 1366 else 1367 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1368 1369 /* Free PS Poll skb here instead of returning RX_DROP that would 1370 * count as an dropped frame. */ 1371 dev_kfree_skb(rx->skb); 1372 1373 return RX_QUEUED; 1374 } 1375 1376 static ieee80211_rx_result debug_noinline 1377 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1378 { 1379 u8 *data = rx->skb->data; 1380 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1381 1382 if (!ieee80211_is_data_qos(hdr->frame_control)) 1383 return RX_CONTINUE; 1384 1385 /* remove the qos control field, update frame type and meta-data */ 1386 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1387 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1388 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1389 /* change frame type to non QOS */ 1390 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1391 1392 return RX_CONTINUE; 1393 } 1394 1395 static int 1396 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1397 { 1398 if (unlikely(!rx->sta || 1399 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1400 return -EACCES; 1401 1402 return 0; 1403 } 1404 1405 static int 1406 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1407 { 1408 struct sk_buff *skb = rx->skb; 1409 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1410 1411 /* 1412 * Pass through unencrypted frames if the hardware has 1413 * decrypted them already. 1414 */ 1415 if (status->flag & RX_FLAG_DECRYPTED) 1416 return 0; 1417 1418 /* Drop unencrypted frames if key is set. */ 1419 if (unlikely(!ieee80211_has_protected(fc) && 1420 !ieee80211_is_nullfunc(fc) && 1421 ieee80211_is_data(fc) && 1422 (rx->key || rx->sdata->drop_unencrypted))) 1423 return -EACCES; 1424 1425 return 0; 1426 } 1427 1428 static int 1429 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) 1430 { 1431 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1432 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1433 __le16 fc = hdr->frame_control; 1434 1435 /* 1436 * Pass through unencrypted frames if the hardware has 1437 * decrypted them already. 1438 */ 1439 if (status->flag & RX_FLAG_DECRYPTED) 1440 return 0; 1441 1442 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1443 if (unlikely(!ieee80211_has_protected(fc) && 1444 ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1445 rx->key)) 1446 return -EACCES; 1447 /* BIP does not use Protected field, so need to check MMIE */ 1448 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && 1449 ieee80211_get_mmie_keyidx(rx->skb) < 0)) 1450 return -EACCES; 1451 /* 1452 * When using MFP, Action frames are not allowed prior to 1453 * having configured keys. 1454 */ 1455 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1456 ieee80211_is_robust_mgmt_frame( 1457 (struct ieee80211_hdr *) rx->skb->data))) 1458 return -EACCES; 1459 } 1460 1461 return 0; 1462 } 1463 1464 static int 1465 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1466 { 1467 struct ieee80211_sub_if_data *sdata = rx->sdata; 1468 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1469 1470 if (ieee80211_has_a4(hdr->frame_control) && 1471 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) 1472 return -1; 1473 1474 if (is_multicast_ether_addr(hdr->addr1) && 1475 ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) || 1476 (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr))) 1477 return -1; 1478 1479 return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); 1480 } 1481 1482 /* 1483 * requires that rx->skb is a frame with ethernet header 1484 */ 1485 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1486 { 1487 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1488 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1489 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1490 1491 /* 1492 * Allow EAPOL frames to us/the PAE group address regardless 1493 * of whether the frame was encrypted or not. 1494 */ 1495 if (ehdr->h_proto == htons(ETH_P_PAE) && 1496 (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || 1497 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1498 return true; 1499 1500 if (ieee80211_802_1x_port_control(rx) || 1501 ieee80211_drop_unencrypted(rx, fc)) 1502 return false; 1503 1504 return true; 1505 } 1506 1507 /* 1508 * requires that rx->skb is a frame with ethernet header 1509 */ 1510 static void 1511 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1512 { 1513 struct ieee80211_sub_if_data *sdata = rx->sdata; 1514 struct net_device *dev = sdata->dev; 1515 struct sk_buff *skb, *xmit_skb; 1516 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1517 struct sta_info *dsta; 1518 1519 skb = rx->skb; 1520 xmit_skb = NULL; 1521 1522 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1523 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1524 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1525 (rx->flags & IEEE80211_RX_RA_MATCH) && 1526 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { 1527 if (is_multicast_ether_addr(ehdr->h_dest)) { 1528 /* 1529 * send multicast frames both to higher layers in 1530 * local net stack and back to the wireless medium 1531 */ 1532 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1533 if (!xmit_skb && net_ratelimit()) 1534 printk(KERN_DEBUG "%s: failed to clone " 1535 "multicast frame\n", dev->name); 1536 } else { 1537 dsta = sta_info_get(sdata, skb->data); 1538 if (dsta) { 1539 /* 1540 * The destination station is associated to 1541 * this AP (in this VLAN), so send the frame 1542 * directly to it and do not pass it to local 1543 * net stack. 1544 */ 1545 xmit_skb = skb; 1546 skb = NULL; 1547 } 1548 } 1549 } 1550 1551 if (skb) { 1552 int align __maybe_unused; 1553 1554 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1555 /* 1556 * 'align' will only take the values 0 or 2 here 1557 * since all frames are required to be aligned 1558 * to 2-byte boundaries when being passed to 1559 * mac80211. That also explains the __skb_push() 1560 * below. 1561 */ 1562 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1563 if (align) { 1564 if (WARN_ON(skb_headroom(skb) < 3)) { 1565 dev_kfree_skb(skb); 1566 skb = NULL; 1567 } else { 1568 u8 *data = skb->data; 1569 size_t len = skb_headlen(skb); 1570 skb->data -= align; 1571 memmove(skb->data, data, len); 1572 skb_set_tail_pointer(skb, len); 1573 } 1574 } 1575 #endif 1576 1577 if (skb) { 1578 /* deliver to local stack */ 1579 skb->protocol = eth_type_trans(skb, dev); 1580 memset(skb->cb, 0, sizeof(skb->cb)); 1581 netif_receive_skb(skb); 1582 } 1583 } 1584 1585 if (xmit_skb) { 1586 /* send to wireless media */ 1587 xmit_skb->protocol = htons(ETH_P_802_3); 1588 skb_reset_network_header(xmit_skb); 1589 skb_reset_mac_header(xmit_skb); 1590 dev_queue_xmit(xmit_skb); 1591 } 1592 } 1593 1594 static ieee80211_rx_result debug_noinline 1595 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1596 { 1597 struct net_device *dev = rx->sdata->dev; 1598 struct sk_buff *skb = rx->skb; 1599 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1600 __le16 fc = hdr->frame_control; 1601 struct sk_buff_head frame_list; 1602 1603 if (unlikely(!ieee80211_is_data(fc))) 1604 return RX_CONTINUE; 1605 1606 if (unlikely(!ieee80211_is_data_present(fc))) 1607 return RX_DROP_MONITOR; 1608 1609 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1610 return RX_CONTINUE; 1611 1612 if (ieee80211_has_a4(hdr->frame_control) && 1613 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1614 !rx->sdata->u.vlan.sta) 1615 return RX_DROP_UNUSABLE; 1616 1617 if (is_multicast_ether_addr(hdr->addr1) && 1618 ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1619 rx->sdata->u.vlan.sta) || 1620 (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 1621 rx->sdata->u.mgd.use_4addr))) 1622 return RX_DROP_UNUSABLE; 1623 1624 skb->dev = dev; 1625 __skb_queue_head_init(&frame_list); 1626 1627 if (skb_linearize(skb)) 1628 return RX_DROP_UNUSABLE; 1629 1630 ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, 1631 rx->sdata->vif.type, 1632 rx->local->hw.extra_tx_headroom); 1633 1634 while (!skb_queue_empty(&frame_list)) { 1635 rx->skb = __skb_dequeue(&frame_list); 1636 1637 if (!ieee80211_frame_allowed(rx, fc)) { 1638 dev_kfree_skb(rx->skb); 1639 continue; 1640 } 1641 dev->stats.rx_packets++; 1642 dev->stats.rx_bytes += rx->skb->len; 1643 1644 ieee80211_deliver_skb(rx); 1645 } 1646 1647 return RX_QUEUED; 1648 } 1649 1650 #ifdef CONFIG_MAC80211_MESH 1651 static ieee80211_rx_result 1652 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1653 { 1654 struct ieee80211_hdr *hdr; 1655 struct ieee80211s_hdr *mesh_hdr; 1656 unsigned int hdrlen; 1657 struct sk_buff *skb = rx->skb, *fwd_skb; 1658 struct ieee80211_local *local = rx->local; 1659 struct ieee80211_sub_if_data *sdata = rx->sdata; 1660 1661 hdr = (struct ieee80211_hdr *) skb->data; 1662 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1663 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1664 1665 if (!ieee80211_is_data(hdr->frame_control)) 1666 return RX_CONTINUE; 1667 1668 if (!mesh_hdr->ttl) 1669 /* illegal frame */ 1670 return RX_DROP_MONITOR; 1671 1672 if (mesh_hdr->flags & MESH_FLAGS_AE) { 1673 struct mesh_path *mppath; 1674 char *proxied_addr; 1675 char *mpp_addr; 1676 1677 if (is_multicast_ether_addr(hdr->addr1)) { 1678 mpp_addr = hdr->addr3; 1679 proxied_addr = mesh_hdr->eaddr1; 1680 } else { 1681 mpp_addr = hdr->addr4; 1682 proxied_addr = mesh_hdr->eaddr2; 1683 } 1684 1685 rcu_read_lock(); 1686 mppath = mpp_path_lookup(proxied_addr, sdata); 1687 if (!mppath) { 1688 mpp_path_add(proxied_addr, mpp_addr, sdata); 1689 } else { 1690 spin_lock_bh(&mppath->state_lock); 1691 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) 1692 memcpy(mppath->mpp, mpp_addr, ETH_ALEN); 1693 spin_unlock_bh(&mppath->state_lock); 1694 } 1695 rcu_read_unlock(); 1696 } 1697 1698 /* Frame has reached destination. Don't forward */ 1699 if (!is_multicast_ether_addr(hdr->addr1) && 1700 compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) 1701 return RX_CONTINUE; 1702 1703 mesh_hdr->ttl--; 1704 1705 if (rx->flags & IEEE80211_RX_RA_MATCH) { 1706 if (!mesh_hdr->ttl) 1707 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1708 dropped_frames_ttl); 1709 else { 1710 struct ieee80211_hdr *fwd_hdr; 1711 struct ieee80211_tx_info *info; 1712 1713 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1714 1715 if (!fwd_skb && net_ratelimit()) 1716 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1717 sdata->name); 1718 1719 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1720 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); 1721 info = IEEE80211_SKB_CB(fwd_skb); 1722 memset(info, 0, sizeof(*info)); 1723 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1724 info->control.vif = &rx->sdata->vif; 1725 skb_set_queue_mapping(skb, 1726 ieee80211_select_queue(rx->sdata, fwd_skb)); 1727 ieee80211_set_qos_hdr(local, skb); 1728 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1729 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1730 fwded_mcast); 1731 else { 1732 int err; 1733 /* 1734 * Save TA to addr1 to send TA a path error if a 1735 * suitable next hop is not found 1736 */ 1737 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1738 ETH_ALEN); 1739 err = mesh_nexthop_lookup(fwd_skb, sdata); 1740 /* Failed to immediately resolve next hop: 1741 * fwded frame was dropped or will be added 1742 * later to the pending skb queue. */ 1743 if (err) 1744 return RX_DROP_MONITOR; 1745 1746 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1747 fwded_unicast); 1748 } 1749 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1750 fwded_frames); 1751 ieee80211_add_pending_skb(local, fwd_skb); 1752 } 1753 } 1754 1755 if (is_multicast_ether_addr(hdr->addr1) || 1756 sdata->dev->flags & IFF_PROMISC) 1757 return RX_CONTINUE; 1758 else 1759 return RX_DROP_MONITOR; 1760 } 1761 #endif 1762 1763 static ieee80211_rx_result debug_noinline 1764 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1765 { 1766 struct ieee80211_sub_if_data *sdata = rx->sdata; 1767 struct ieee80211_local *local = rx->local; 1768 struct net_device *dev = sdata->dev; 1769 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1770 __le16 fc = hdr->frame_control; 1771 int err; 1772 1773 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1774 return RX_CONTINUE; 1775 1776 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1777 return RX_DROP_MONITOR; 1778 1779 /* 1780 * Allow the cooked monitor interface of an AP to see 4-addr frames so 1781 * that a 4-addr station can be detected and moved into a separate VLAN 1782 */ 1783 if (ieee80211_has_a4(hdr->frame_control) && 1784 sdata->vif.type == NL80211_IFTYPE_AP) 1785 return RX_DROP_MONITOR; 1786 1787 err = __ieee80211_data_to_8023(rx); 1788 if (unlikely(err)) 1789 return RX_DROP_UNUSABLE; 1790 1791 if (!ieee80211_frame_allowed(rx, fc)) 1792 return RX_DROP_MONITOR; 1793 1794 rx->skb->dev = dev; 1795 1796 dev->stats.rx_packets++; 1797 dev->stats.rx_bytes += rx->skb->len; 1798 1799 if (ieee80211_is_data(hdr->frame_control) && 1800 !is_multicast_ether_addr(hdr->addr1) && 1801 local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) { 1802 mod_timer(&local->dynamic_ps_timer, jiffies + 1803 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1804 } 1805 1806 ieee80211_deliver_skb(rx); 1807 1808 return RX_QUEUED; 1809 } 1810 1811 static ieee80211_rx_result debug_noinline 1812 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames) 1813 { 1814 struct ieee80211_local *local = rx->local; 1815 struct ieee80211_hw *hw = &local->hw; 1816 struct sk_buff *skb = rx->skb; 1817 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1818 struct tid_ampdu_rx *tid_agg_rx; 1819 u16 start_seq_num; 1820 u16 tid; 1821 1822 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1823 return RX_CONTINUE; 1824 1825 if (ieee80211_is_back_req(bar->frame_control)) { 1826 struct { 1827 __le16 control, start_seq_num; 1828 } __packed bar_data; 1829 1830 if (!rx->sta) 1831 return RX_DROP_MONITOR; 1832 1833 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control), 1834 &bar_data, sizeof(bar_data))) 1835 return RX_DROP_MONITOR; 1836 1837 tid = le16_to_cpu(bar_data.control) >> 12; 1838 1839 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]); 1840 if (!tid_agg_rx) 1841 return RX_DROP_MONITOR; 1842 1843 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4; 1844 1845 /* reset session timer */ 1846 if (tid_agg_rx->timeout) 1847 mod_timer(&tid_agg_rx->session_timer, 1848 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1849 1850 /* release stored frames up to start of BAR */ 1851 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num, 1852 frames); 1853 kfree_skb(skb); 1854 return RX_QUEUED; 1855 } 1856 1857 /* 1858 * After this point, we only want management frames, 1859 * so we can drop all remaining control frames to 1860 * cooked monitor interfaces. 1861 */ 1862 return RX_DROP_MONITOR; 1863 } 1864 1865 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 1866 struct ieee80211_mgmt *mgmt, 1867 size_t len) 1868 { 1869 struct ieee80211_local *local = sdata->local; 1870 struct sk_buff *skb; 1871 struct ieee80211_mgmt *resp; 1872 1873 if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { 1874 /* Not to own unicast address */ 1875 return; 1876 } 1877 1878 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 1879 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 1880 /* Not from the current AP or not associated yet. */ 1881 return; 1882 } 1883 1884 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 1885 /* Too short SA Query request frame */ 1886 return; 1887 } 1888 1889 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 1890 if (skb == NULL) 1891 return; 1892 1893 skb_reserve(skb, local->hw.extra_tx_headroom); 1894 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 1895 memset(resp, 0, 24); 1896 memcpy(resp->da, mgmt->sa, ETH_ALEN); 1897 memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); 1898 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 1899 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 1900 IEEE80211_STYPE_ACTION); 1901 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 1902 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 1903 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 1904 memcpy(resp->u.action.u.sa_query.trans_id, 1905 mgmt->u.action.u.sa_query.trans_id, 1906 WLAN_SA_QUERY_TR_ID_LEN); 1907 1908 ieee80211_tx_skb(sdata, skb); 1909 } 1910 1911 static ieee80211_rx_result debug_noinline 1912 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 1913 { 1914 struct ieee80211_local *local = rx->local; 1915 struct ieee80211_sub_if_data *sdata = rx->sdata; 1916 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1917 struct sk_buff *nskb; 1918 struct ieee80211_rx_status *status; 1919 int len = rx->skb->len; 1920 1921 if (!ieee80211_is_action(mgmt->frame_control)) 1922 return RX_CONTINUE; 1923 1924 /* drop too small frames */ 1925 if (len < IEEE80211_MIN_ACTION_SIZE) 1926 return RX_DROP_UNUSABLE; 1927 1928 if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) 1929 return RX_DROP_UNUSABLE; 1930 1931 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1932 return RX_DROP_UNUSABLE; 1933 1934 if (ieee80211_drop_unencrypted_mgmt(rx)) 1935 return RX_DROP_UNUSABLE; 1936 1937 switch (mgmt->u.action.category) { 1938 case WLAN_CATEGORY_BACK: 1939 /* 1940 * The aggregation code is not prepared to handle 1941 * anything but STA/AP due to the BSSID handling; 1942 * IBSS could work in the code but isn't supported 1943 * by drivers or the standard. 1944 */ 1945 if (sdata->vif.type != NL80211_IFTYPE_STATION && 1946 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 1947 sdata->vif.type != NL80211_IFTYPE_AP) 1948 break; 1949 1950 /* verify action_code is present */ 1951 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1952 break; 1953 1954 switch (mgmt->u.action.u.addba_req.action_code) { 1955 case WLAN_ACTION_ADDBA_REQ: 1956 if (len < (IEEE80211_MIN_ACTION_SIZE + 1957 sizeof(mgmt->u.action.u.addba_req))) 1958 goto invalid; 1959 break; 1960 case WLAN_ACTION_ADDBA_RESP: 1961 if (len < (IEEE80211_MIN_ACTION_SIZE + 1962 sizeof(mgmt->u.action.u.addba_resp))) 1963 goto invalid; 1964 break; 1965 case WLAN_ACTION_DELBA: 1966 if (len < (IEEE80211_MIN_ACTION_SIZE + 1967 sizeof(mgmt->u.action.u.delba))) 1968 goto invalid; 1969 break; 1970 default: 1971 goto invalid; 1972 } 1973 1974 goto queue; 1975 case WLAN_CATEGORY_SPECTRUM_MGMT: 1976 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 1977 break; 1978 1979 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1980 break; 1981 1982 /* verify action_code is present */ 1983 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1984 break; 1985 1986 switch (mgmt->u.action.u.measurement.action_code) { 1987 case WLAN_ACTION_SPCT_MSR_REQ: 1988 if (len < (IEEE80211_MIN_ACTION_SIZE + 1989 sizeof(mgmt->u.action.u.measurement))) 1990 break; 1991 ieee80211_process_measurement_req(sdata, mgmt, len); 1992 goto handled; 1993 case WLAN_ACTION_SPCT_CHL_SWITCH: 1994 if (len < (IEEE80211_MIN_ACTION_SIZE + 1995 sizeof(mgmt->u.action.u.chan_switch))) 1996 break; 1997 1998 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1999 break; 2000 2001 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 2002 break; 2003 2004 goto queue; 2005 } 2006 break; 2007 case WLAN_CATEGORY_SA_QUERY: 2008 if (len < (IEEE80211_MIN_ACTION_SIZE + 2009 sizeof(mgmt->u.action.u.sa_query))) 2010 break; 2011 2012 switch (mgmt->u.action.u.sa_query.action) { 2013 case WLAN_ACTION_SA_QUERY_REQUEST: 2014 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2015 break; 2016 ieee80211_process_sa_query_req(sdata, mgmt, len); 2017 goto handled; 2018 } 2019 break; 2020 case WLAN_CATEGORY_MESH_PLINK: 2021 case WLAN_CATEGORY_MESH_PATH_SEL: 2022 if (!ieee80211_vif_is_mesh(&sdata->vif)) 2023 break; 2024 goto queue; 2025 } 2026 2027 invalid: 2028 /* 2029 * For AP mode, hostapd is responsible for handling any action 2030 * frames that we didn't handle, including returning unknown 2031 * ones. For all other modes we will return them to the sender, 2032 * setting the 0x80 bit in the action category, as required by 2033 * 802.11-2007 7.3.1.11. 2034 */ 2035 if (sdata->vif.type == NL80211_IFTYPE_AP || 2036 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2037 return RX_DROP_MONITOR; 2038 2039 /* 2040 * Getting here means the kernel doesn't know how to handle 2041 * it, but maybe userspace does ... include returned frames 2042 * so userspace can register for those to know whether ones 2043 * it transmitted were processed or returned. 2044 */ 2045 status = IEEE80211_SKB_RXCB(rx->skb); 2046 2047 if (cfg80211_rx_action(rx->sdata->dev, status->freq, 2048 rx->skb->data, rx->skb->len, 2049 GFP_ATOMIC)) 2050 goto handled; 2051 2052 /* do not return rejected action frames */ 2053 if (mgmt->u.action.category & 0x80) 2054 return RX_DROP_UNUSABLE; 2055 2056 nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0, 2057 GFP_ATOMIC); 2058 if (nskb) { 2059 struct ieee80211_mgmt *nmgmt = (void *)nskb->data; 2060 2061 nmgmt->u.action.category |= 0x80; 2062 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN); 2063 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN); 2064 2065 memset(nskb->cb, 0, sizeof(nskb->cb)); 2066 2067 ieee80211_tx_skb(rx->sdata, nskb); 2068 } 2069 2070 handled: 2071 if (rx->sta) 2072 rx->sta->rx_packets++; 2073 dev_kfree_skb(rx->skb); 2074 return RX_QUEUED; 2075 2076 queue: 2077 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2078 skb_queue_tail(&sdata->skb_queue, rx->skb); 2079 ieee80211_queue_work(&local->hw, &sdata->work); 2080 if (rx->sta) 2081 rx->sta->rx_packets++; 2082 return RX_QUEUED; 2083 } 2084 2085 static ieee80211_rx_result debug_noinline 2086 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 2087 { 2088 struct ieee80211_sub_if_data *sdata = rx->sdata; 2089 ieee80211_rx_result rxs; 2090 struct ieee80211_mgmt *mgmt = (void *)rx->skb->data; 2091 __le16 stype; 2092 2093 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 2094 return RX_DROP_MONITOR; 2095 2096 if (rx->skb->len < 24) 2097 return RX_DROP_MONITOR; 2098 2099 if (ieee80211_drop_unencrypted_mgmt(rx)) 2100 return RX_DROP_UNUSABLE; 2101 2102 rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); 2103 if (rxs != RX_CONTINUE) 2104 return rxs; 2105 2106 stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE); 2107 2108 if (!ieee80211_vif_is_mesh(&sdata->vif) && 2109 sdata->vif.type != NL80211_IFTYPE_ADHOC && 2110 sdata->vif.type != NL80211_IFTYPE_STATION) 2111 return RX_DROP_MONITOR; 2112 2113 switch (stype) { 2114 case cpu_to_le16(IEEE80211_STYPE_BEACON): 2115 case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP): 2116 /* process for all: mesh, mlme, ibss */ 2117 break; 2118 case cpu_to_le16(IEEE80211_STYPE_DEAUTH): 2119 case cpu_to_le16(IEEE80211_STYPE_DISASSOC): 2120 /* process only for station */ 2121 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2122 return RX_DROP_MONITOR; 2123 break; 2124 case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ): 2125 case cpu_to_le16(IEEE80211_STYPE_AUTH): 2126 /* process only for ibss */ 2127 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 2128 return RX_DROP_MONITOR; 2129 break; 2130 default: 2131 return RX_DROP_MONITOR; 2132 } 2133 2134 /* queue up frame and kick off work to process it */ 2135 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2136 skb_queue_tail(&sdata->skb_queue, rx->skb); 2137 ieee80211_queue_work(&rx->local->hw, &sdata->work); 2138 if (rx->sta) 2139 rx->sta->rx_packets++; 2140 2141 return RX_QUEUED; 2142 } 2143 2144 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 2145 struct ieee80211_rx_data *rx) 2146 { 2147 int keyidx; 2148 unsigned int hdrlen; 2149 2150 hdrlen = ieee80211_hdrlen(hdr->frame_control); 2151 if (rx->skb->len >= hdrlen + 4) 2152 keyidx = rx->skb->data[hdrlen + 3] >> 6; 2153 else 2154 keyidx = -1; 2155 2156 if (!rx->sta) { 2157 /* 2158 * Some hardware seem to generate incorrect Michael MIC 2159 * reports; ignore them to avoid triggering countermeasures. 2160 */ 2161 return; 2162 } 2163 2164 if (!ieee80211_has_protected(hdr->frame_control)) 2165 return; 2166 2167 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 2168 /* 2169 * APs with pairwise keys should never receive Michael MIC 2170 * errors for non-zero keyidx because these are reserved for 2171 * group keys and only the AP is sending real multicast 2172 * frames in the BSS. 2173 */ 2174 return; 2175 } 2176 2177 if (!ieee80211_is_data(hdr->frame_control) && 2178 !ieee80211_is_auth(hdr->frame_control)) 2179 return; 2180 2181 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 2182 GFP_ATOMIC); 2183 } 2184 2185 /* TODO: use IEEE80211_RX_FRAGMENTED */ 2186 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, 2187 struct ieee80211_rate *rate) 2188 { 2189 struct ieee80211_sub_if_data *sdata; 2190 struct ieee80211_local *local = rx->local; 2191 struct ieee80211_rtap_hdr { 2192 struct ieee80211_radiotap_header hdr; 2193 u8 flags; 2194 u8 rate_or_pad; 2195 __le16 chan_freq; 2196 __le16 chan_flags; 2197 } __packed *rthdr; 2198 struct sk_buff *skb = rx->skb, *skb2; 2199 struct net_device *prev_dev = NULL; 2200 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2201 2202 if (status->flag & RX_FLAG_INTERNAL_CMTR) 2203 goto out_free_skb; 2204 2205 if (skb_headroom(skb) < sizeof(*rthdr) && 2206 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 2207 goto out_free_skb; 2208 2209 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 2210 memset(rthdr, 0, sizeof(*rthdr)); 2211 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 2212 rthdr->hdr.it_present = 2213 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 2214 (1 << IEEE80211_RADIOTAP_CHANNEL)); 2215 2216 if (rate) { 2217 rthdr->rate_or_pad = rate->bitrate / 5; 2218 rthdr->hdr.it_present |= 2219 cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 2220 } 2221 rthdr->chan_freq = cpu_to_le16(status->freq); 2222 2223 if (status->band == IEEE80211_BAND_5GHZ) 2224 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 2225 IEEE80211_CHAN_5GHZ); 2226 else 2227 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 2228 IEEE80211_CHAN_2GHZ); 2229 2230 skb_set_mac_header(skb, 0); 2231 skb->ip_summed = CHECKSUM_UNNECESSARY; 2232 skb->pkt_type = PACKET_OTHERHOST; 2233 skb->protocol = htons(ETH_P_802_2); 2234 2235 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2236 if (!ieee80211_sdata_running(sdata)) 2237 continue; 2238 2239 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 2240 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 2241 continue; 2242 2243 if (prev_dev) { 2244 skb2 = skb_clone(skb, GFP_ATOMIC); 2245 if (skb2) { 2246 skb2->dev = prev_dev; 2247 netif_receive_skb(skb2); 2248 } 2249 } 2250 2251 prev_dev = sdata->dev; 2252 sdata->dev->stats.rx_packets++; 2253 sdata->dev->stats.rx_bytes += skb->len; 2254 } 2255 2256 if (prev_dev) { 2257 skb->dev = prev_dev; 2258 netif_receive_skb(skb); 2259 skb = NULL; 2260 } else 2261 goto out_free_skb; 2262 2263 status->flag |= RX_FLAG_INTERNAL_CMTR; 2264 return; 2265 2266 out_free_skb: 2267 dev_kfree_skb(skb); 2268 } 2269 2270 2271 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 2272 struct ieee80211_rx_data *rx, 2273 struct sk_buff *skb, 2274 struct ieee80211_rate *rate) 2275 { 2276 struct sk_buff_head reorder_release; 2277 ieee80211_rx_result res = RX_DROP_MONITOR; 2278 2279 __skb_queue_head_init(&reorder_release); 2280 2281 rx->skb = skb; 2282 rx->sdata = sdata; 2283 2284 #define CALL_RXH(rxh) \ 2285 do { \ 2286 res = rxh(rx); \ 2287 if (res != RX_CONTINUE) \ 2288 goto rxh_next; \ 2289 } while (0); 2290 2291 /* 2292 * NB: the rxh_next label works even if we jump 2293 * to it from here because then the list will 2294 * be empty, which is a trivial check 2295 */ 2296 CALL_RXH(ieee80211_rx_h_passive_scan) 2297 CALL_RXH(ieee80211_rx_h_check) 2298 2299 ieee80211_rx_reorder_ampdu(rx, &reorder_release); 2300 2301 while ((skb = __skb_dequeue(&reorder_release))) { 2302 /* 2303 * all the other fields are valid across frames 2304 * that belong to an aMPDU since they are on the 2305 * same TID from the same station 2306 */ 2307 rx->skb = skb; 2308 2309 CALL_RXH(ieee80211_rx_h_decrypt) 2310 CALL_RXH(ieee80211_rx_h_check_more_data) 2311 CALL_RXH(ieee80211_rx_h_sta_process) 2312 CALL_RXH(ieee80211_rx_h_defragment) 2313 CALL_RXH(ieee80211_rx_h_ps_poll) 2314 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 2315 /* must be after MMIC verify so header is counted in MPDU mic */ 2316 CALL_RXH(ieee80211_rx_h_remove_qos_control) 2317 CALL_RXH(ieee80211_rx_h_amsdu) 2318 #ifdef CONFIG_MAC80211_MESH 2319 if (ieee80211_vif_is_mesh(&sdata->vif)) 2320 CALL_RXH(ieee80211_rx_h_mesh_fwding); 2321 #endif 2322 CALL_RXH(ieee80211_rx_h_data) 2323 2324 /* special treatment -- needs the queue */ 2325 res = ieee80211_rx_h_ctrl(rx, &reorder_release); 2326 if (res != RX_CONTINUE) 2327 goto rxh_next; 2328 2329 CALL_RXH(ieee80211_rx_h_action) 2330 CALL_RXH(ieee80211_rx_h_mgmt) 2331 2332 #undef CALL_RXH 2333 2334 rxh_next: 2335 switch (res) { 2336 case RX_DROP_MONITOR: 2337 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2338 if (rx->sta) 2339 rx->sta->rx_dropped++; 2340 /* fall through */ 2341 case RX_CONTINUE: 2342 ieee80211_rx_cooked_monitor(rx, rate); 2343 break; 2344 case RX_DROP_UNUSABLE: 2345 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2346 if (rx->sta) 2347 rx->sta->rx_dropped++; 2348 dev_kfree_skb(rx->skb); 2349 break; 2350 case RX_QUEUED: 2351 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 2352 break; 2353 } 2354 } 2355 } 2356 2357 /* main receive path */ 2358 2359 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 2360 struct ieee80211_rx_data *rx, 2361 struct ieee80211_hdr *hdr) 2362 { 2363 struct sk_buff *skb = rx->skb; 2364 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2365 u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 2366 int multicast = is_multicast_ether_addr(hdr->addr1); 2367 2368 switch (sdata->vif.type) { 2369 case NL80211_IFTYPE_STATION: 2370 if (!bssid && !sdata->u.mgd.use_4addr) 2371 return 0; 2372 if (!multicast && 2373 compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { 2374 if (!(sdata->dev->flags & IFF_PROMISC)) 2375 return 0; 2376 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2377 } 2378 break; 2379 case NL80211_IFTYPE_ADHOC: 2380 if (!bssid) 2381 return 0; 2382 if (ieee80211_is_beacon(hdr->frame_control)) { 2383 return 1; 2384 } 2385 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2386 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2387 return 0; 2388 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2389 } else if (!multicast && 2390 compare_ether_addr(sdata->vif.addr, 2391 hdr->addr1) != 0) { 2392 if (!(sdata->dev->flags & IFF_PROMISC)) 2393 return 0; 2394 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2395 } else if (!rx->sta) { 2396 int rate_idx; 2397 if (status->flag & RX_FLAG_HT) 2398 rate_idx = 0; /* TODO: HT rates */ 2399 else 2400 rate_idx = status->rate_idx; 2401 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, 2402 hdr->addr2, BIT(rate_idx), GFP_ATOMIC); 2403 } 2404 break; 2405 case NL80211_IFTYPE_MESH_POINT: 2406 if (!multicast && 2407 compare_ether_addr(sdata->vif.addr, 2408 hdr->addr1) != 0) { 2409 if (!(sdata->dev->flags & IFF_PROMISC)) 2410 return 0; 2411 2412 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2413 } 2414 break; 2415 case NL80211_IFTYPE_AP_VLAN: 2416 case NL80211_IFTYPE_AP: 2417 if (!bssid) { 2418 if (compare_ether_addr(sdata->vif.addr, 2419 hdr->addr1)) 2420 return 0; 2421 } else if (!ieee80211_bssid_match(bssid, 2422 sdata->vif.addr)) { 2423 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2424 return 0; 2425 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2426 } 2427 break; 2428 case NL80211_IFTYPE_WDS: 2429 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2430 return 0; 2431 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2432 return 0; 2433 break; 2434 case NL80211_IFTYPE_MONITOR: 2435 case NL80211_IFTYPE_UNSPECIFIED: 2436 case __NL80211_IFTYPE_AFTER_LAST: 2437 /* should never get here */ 2438 WARN_ON(1); 2439 break; 2440 } 2441 2442 return 1; 2443 } 2444 2445 /* 2446 * This is the actual Rx frames handler. as it blongs to Rx path it must 2447 * be called with rcu_read_lock protection. 2448 */ 2449 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2450 struct sk_buff *skb, 2451 struct ieee80211_rate *rate) 2452 { 2453 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2454 struct ieee80211_local *local = hw_to_local(hw); 2455 struct ieee80211_sub_if_data *sdata; 2456 struct ieee80211_hdr *hdr; 2457 __le16 fc; 2458 struct ieee80211_rx_data rx; 2459 int prepares; 2460 struct ieee80211_sub_if_data *prev = NULL; 2461 struct sk_buff *skb_new; 2462 struct sta_info *sta, *tmp; 2463 bool found_sta = false; 2464 int err = 0; 2465 2466 fc = ((struct ieee80211_hdr *)skb->data)->frame_control; 2467 memset(&rx, 0, sizeof(rx)); 2468 rx.skb = skb; 2469 rx.local = local; 2470 2471 if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) 2472 local->dot11ReceivedFragmentCount++; 2473 2474 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2475 test_bit(SCAN_OFF_CHANNEL, &local->scanning))) 2476 rx.flags |= IEEE80211_RX_IN_SCAN; 2477 2478 if (ieee80211_is_mgmt(fc)) 2479 err = skb_linearize(skb); 2480 else 2481 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); 2482 2483 if (err) { 2484 dev_kfree_skb(skb); 2485 return; 2486 } 2487 2488 hdr = (struct ieee80211_hdr *)skb->data; 2489 ieee80211_parse_qos(&rx); 2490 ieee80211_verify_alignment(&rx); 2491 2492 if (ieee80211_is_data(fc)) { 2493 for_each_sta_info(local, hdr->addr2, sta, tmp) { 2494 rx.sta = sta; 2495 found_sta = true; 2496 rx.sdata = sta->sdata; 2497 2498 rx.flags |= IEEE80211_RX_RA_MATCH; 2499 prepares = prepare_for_handlers(rx.sdata, &rx, hdr); 2500 if (prepares) { 2501 if (status->flag & RX_FLAG_MMIC_ERROR) { 2502 if (rx.flags & IEEE80211_RX_RA_MATCH) 2503 ieee80211_rx_michael_mic_report(hdr, &rx); 2504 } else 2505 prev = rx.sdata; 2506 } 2507 } 2508 } 2509 if (!found_sta) { 2510 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2511 if (!ieee80211_sdata_running(sdata)) 2512 continue; 2513 2514 if (sdata->vif.type == NL80211_IFTYPE_MONITOR || 2515 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2516 continue; 2517 2518 /* 2519 * frame is destined for this interface, but if it's 2520 * not also for the previous one we handle that after 2521 * the loop to avoid copying the SKB once too much 2522 */ 2523 2524 if (!prev) { 2525 prev = sdata; 2526 continue; 2527 } 2528 2529 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2530 2531 rx.flags |= IEEE80211_RX_RA_MATCH; 2532 prepares = prepare_for_handlers(prev, &rx, hdr); 2533 2534 if (!prepares) 2535 goto next; 2536 2537 if (status->flag & RX_FLAG_MMIC_ERROR) { 2538 rx.sdata = prev; 2539 if (rx.flags & IEEE80211_RX_RA_MATCH) 2540 ieee80211_rx_michael_mic_report(hdr, 2541 &rx); 2542 goto next; 2543 } 2544 2545 /* 2546 * frame was destined for the previous interface 2547 * so invoke RX handlers for it 2548 */ 2549 2550 skb_new = skb_copy(skb, GFP_ATOMIC); 2551 if (!skb_new) { 2552 if (net_ratelimit()) 2553 printk(KERN_DEBUG "%s: failed to copy " 2554 "multicast frame for %s\n", 2555 wiphy_name(local->hw.wiphy), 2556 prev->name); 2557 goto next; 2558 } 2559 ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate); 2560 next: 2561 prev = sdata; 2562 } 2563 2564 if (prev) { 2565 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2566 2567 rx.flags |= IEEE80211_RX_RA_MATCH; 2568 prepares = prepare_for_handlers(prev, &rx, hdr); 2569 2570 if (!prepares) 2571 prev = NULL; 2572 } 2573 } 2574 if (prev) 2575 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate); 2576 else 2577 dev_kfree_skb(skb); 2578 } 2579 2580 /* 2581 * This is the receive path handler. It is called by a low level driver when an 2582 * 802.11 MPDU is received from the hardware. 2583 */ 2584 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2585 { 2586 struct ieee80211_local *local = hw_to_local(hw); 2587 struct ieee80211_rate *rate = NULL; 2588 struct ieee80211_supported_band *sband; 2589 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2590 2591 WARN_ON_ONCE(softirq_count() == 0); 2592 2593 if (WARN_ON(status->band < 0 || 2594 status->band >= IEEE80211_NUM_BANDS)) 2595 goto drop; 2596 2597 sband = local->hw.wiphy->bands[status->band]; 2598 if (WARN_ON(!sband)) 2599 goto drop; 2600 2601 /* 2602 * If we're suspending, it is possible although not too likely 2603 * that we'd be receiving frames after having already partially 2604 * quiesced the stack. We can't process such frames then since 2605 * that might, for example, cause stations to be added or other 2606 * driver callbacks be invoked. 2607 */ 2608 if (unlikely(local->quiescing || local->suspended)) 2609 goto drop; 2610 2611 /* 2612 * The same happens when we're not even started, 2613 * but that's worth a warning. 2614 */ 2615 if (WARN_ON(!local->started)) 2616 goto drop; 2617 2618 if (status->flag & RX_FLAG_HT) { 2619 /* 2620 * rate_idx is MCS index, which can be [0-76] as documented on: 2621 * 2622 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n 2623 * 2624 * Anything else would be some sort of driver or hardware error. 2625 * The driver should catch hardware errors. 2626 */ 2627 if (WARN((status->rate_idx < 0 || 2628 status->rate_idx > 76), 2629 "Rate marked as an HT rate but passed " 2630 "status->rate_idx is not " 2631 "an MCS index [0-76]: %d (0x%02x)\n", 2632 status->rate_idx, 2633 status->rate_idx)) 2634 goto drop; 2635 } else { 2636 if (WARN_ON(status->rate_idx < 0 || 2637 status->rate_idx >= sband->n_bitrates)) 2638 goto drop; 2639 rate = &sband->bitrates[status->rate_idx]; 2640 } 2641 2642 /* 2643 * key references and virtual interfaces are protected using RCU 2644 * and this requires that we are in a read-side RCU section during 2645 * receive processing 2646 */ 2647 rcu_read_lock(); 2648 2649 /* 2650 * Frames with failed FCS/PLCP checksum are not returned, 2651 * all other frames are returned without radiotap header 2652 * if it was previously present. 2653 * Also, frames with less than 16 bytes are dropped. 2654 */ 2655 skb = ieee80211_rx_monitor(local, skb, rate); 2656 if (!skb) { 2657 rcu_read_unlock(); 2658 return; 2659 } 2660 2661 __ieee80211_rx_handle_packet(hw, skb, rate); 2662 2663 rcu_read_unlock(); 2664 2665 return; 2666 drop: 2667 kfree_skb(skb); 2668 } 2669 EXPORT_SYMBOL(ieee80211_rx); 2670 2671 /* This is a version of the rx handler that can be called from hard irq 2672 * context. Post the skb on the queue and schedule the tasklet */ 2673 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2674 { 2675 struct ieee80211_local *local = hw_to_local(hw); 2676 2677 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2678 2679 skb->pkt_type = IEEE80211_RX_MSG; 2680 skb_queue_tail(&local->skb_queue, skb); 2681 tasklet_schedule(&local->tasklet); 2682 } 2683 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2684