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_MACTIME_MPDU) 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 if (status->flag & RX_FLAG_HT) /* HT info */ 89 len += 3; 90 91 return len; 92 } 93 94 /* 95 * ieee80211_add_rx_radiotap_header - add radiotap header 96 * 97 * add a radiotap header containing all the fields which the hardware provided. 98 */ 99 static void 100 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 101 struct sk_buff *skb, 102 struct ieee80211_rate *rate, 103 int rtap_len) 104 { 105 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 106 struct ieee80211_radiotap_header *rthdr; 107 unsigned char *pos; 108 u16 rx_flags = 0; 109 110 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 111 memset(rthdr, 0, rtap_len); 112 113 /* radiotap header, set always present flags */ 114 rthdr->it_present = 115 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 116 (1 << IEEE80211_RADIOTAP_CHANNEL) | 117 (1 << IEEE80211_RADIOTAP_ANTENNA) | 118 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 119 rthdr->it_len = cpu_to_le16(rtap_len); 120 121 pos = (unsigned char *)(rthdr+1); 122 123 /* the order of the following fields is important */ 124 125 /* IEEE80211_RADIOTAP_TSFT */ 126 if (status->flag & RX_FLAG_MACTIME_MPDU) { 127 put_unaligned_le64(status->mactime, pos); 128 rthdr->it_present |= 129 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 130 pos += 8; 131 } 132 133 /* IEEE80211_RADIOTAP_FLAGS */ 134 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 135 *pos |= IEEE80211_RADIOTAP_F_FCS; 136 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 137 *pos |= IEEE80211_RADIOTAP_F_BADFCS; 138 if (status->flag & RX_FLAG_SHORTPRE) 139 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; 140 pos++; 141 142 /* IEEE80211_RADIOTAP_RATE */ 143 if (status->flag & RX_FLAG_HT) { 144 /* 145 * MCS information is a separate field in radiotap, 146 * added below. 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 if (status->flag & RX_FLAG_HT) { 198 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS); 199 *pos++ = IEEE80211_RADIOTAP_MCS_HAVE_MCS | 200 IEEE80211_RADIOTAP_MCS_HAVE_GI | 201 IEEE80211_RADIOTAP_MCS_HAVE_BW; 202 *pos = 0; 203 if (status->flag & RX_FLAG_SHORT_GI) 204 *pos |= IEEE80211_RADIOTAP_MCS_SGI; 205 if (status->flag & RX_FLAG_40MHZ) 206 *pos |= IEEE80211_RADIOTAP_MCS_BW_40; 207 pos++; 208 *pos++ = status->rate_idx; 209 } 210 } 211 212 /* 213 * This function copies a received frame to all monitor interfaces and 214 * returns a cleaned-up SKB that no longer includes the FCS nor the 215 * radiotap header the driver might have added. 216 */ 217 static struct sk_buff * 218 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 219 struct ieee80211_rate *rate) 220 { 221 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); 222 struct ieee80211_sub_if_data *sdata; 223 int needed_headroom = 0; 224 struct sk_buff *skb, *skb2; 225 struct net_device *prev_dev = NULL; 226 int present_fcs_len = 0; 227 228 /* 229 * First, we may need to make a copy of the skb because 230 * (1) we need to modify it for radiotap (if not present), and 231 * (2) the other RX handlers will modify the skb we got. 232 * 233 * We don't need to, of course, if we aren't going to return 234 * the SKB because it has a bad FCS/PLCP checksum. 235 */ 236 237 /* room for the radiotap header based on driver features */ 238 needed_headroom = ieee80211_rx_radiotap_len(local, status); 239 240 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 241 present_fcs_len = FCS_LEN; 242 243 /* make sure hdr->frame_control is on the linear part */ 244 if (!pskb_may_pull(origskb, 2)) { 245 dev_kfree_skb(origskb); 246 return NULL; 247 } 248 249 if (!local->monitors) { 250 if (should_drop_frame(origskb, present_fcs_len)) { 251 dev_kfree_skb(origskb); 252 return NULL; 253 } 254 255 return remove_monitor_info(local, origskb); 256 } 257 258 if (should_drop_frame(origskb, present_fcs_len)) { 259 /* only need to expand headroom if necessary */ 260 skb = origskb; 261 origskb = NULL; 262 263 /* 264 * This shouldn't trigger often because most devices have an 265 * RX header they pull before we get here, and that should 266 * be big enough for our radiotap information. We should 267 * probably export the length to drivers so that we can have 268 * them allocate enough headroom to start with. 269 */ 270 if (skb_headroom(skb) < needed_headroom && 271 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) { 272 dev_kfree_skb(skb); 273 return NULL; 274 } 275 } else { 276 /* 277 * Need to make a copy and possibly remove radiotap header 278 * and FCS from the original. 279 */ 280 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 281 282 origskb = remove_monitor_info(local, origskb); 283 284 if (!skb) 285 return origskb; 286 } 287 288 /* prepend radiotap information */ 289 ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom); 290 291 skb_reset_mac_header(skb); 292 skb->ip_summed = CHECKSUM_UNNECESSARY; 293 skb->pkt_type = PACKET_OTHERHOST; 294 skb->protocol = htons(ETH_P_802_2); 295 296 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 297 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) 298 continue; 299 300 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 301 continue; 302 303 if (!ieee80211_sdata_running(sdata)) 304 continue; 305 306 if (prev_dev) { 307 skb2 = skb_clone(skb, GFP_ATOMIC); 308 if (skb2) { 309 skb2->dev = prev_dev; 310 netif_receive_skb(skb2); 311 } 312 } 313 314 prev_dev = sdata->dev; 315 sdata->dev->stats.rx_packets++; 316 sdata->dev->stats.rx_bytes += skb->len; 317 } 318 319 if (prev_dev) { 320 skb->dev = prev_dev; 321 netif_receive_skb(skb); 322 } else 323 dev_kfree_skb(skb); 324 325 return origskb; 326 } 327 328 329 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 330 { 331 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 332 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 333 int tid; 334 335 /* does the frame have a qos control field? */ 336 if (ieee80211_is_data_qos(hdr->frame_control)) { 337 u8 *qc = ieee80211_get_qos_ctl(hdr); 338 /* frame has qos control */ 339 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 340 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 341 status->rx_flags |= IEEE80211_RX_AMSDU; 342 } else { 343 /* 344 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 345 * 346 * Sequence numbers for management frames, QoS data 347 * frames with a broadcast/multicast address in the 348 * Address 1 field, and all non-QoS data frames sent 349 * by QoS STAs are assigned using an additional single 350 * modulo-4096 counter, [...] 351 * 352 * We also use that counter for non-QoS STAs. 353 */ 354 tid = NUM_RX_DATA_QUEUES - 1; 355 } 356 357 rx->queue = tid; 358 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 359 * For now, set skb->priority to 0 for other cases. */ 360 rx->skb->priority = (tid > 7) ? 0 : tid; 361 } 362 363 /** 364 * DOC: Packet alignment 365 * 366 * Drivers always need to pass packets that are aligned to two-byte boundaries 367 * to the stack. 368 * 369 * Additionally, should, if possible, align the payload data in a way that 370 * guarantees that the contained IP header is aligned to a four-byte 371 * boundary. In the case of regular frames, this simply means aligning the 372 * payload to a four-byte boundary (because either the IP header is directly 373 * contained, or IV/RFC1042 headers that have a length divisible by four are 374 * in front of it). If the payload data is not properly aligned and the 375 * architecture doesn't support efficient unaligned operations, mac80211 376 * will align the data. 377 * 378 * With A-MSDU frames, however, the payload data address must yield two modulo 379 * four because there are 14-byte 802.3 headers within the A-MSDU frames that 380 * push the IP header further back to a multiple of four again. Thankfully, the 381 * specs were sane enough this time around to require padding each A-MSDU 382 * subframe to a length that is a multiple of four. 383 * 384 * Padding like Atheros hardware adds which is inbetween the 802.11 header and 385 * the payload is not supported, the driver is required to move the 802.11 386 * header to be directly in front of the payload in that case. 387 */ 388 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) 389 { 390 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 391 WARN_ONCE((unsigned long)rx->skb->data & 1, 392 "unaligned packet at 0x%p\n", rx->skb->data); 393 #endif 394 } 395 396 397 /* rx handlers */ 398 399 static ieee80211_rx_result debug_noinline 400 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 401 { 402 struct ieee80211_local *local = rx->local; 403 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 404 struct sk_buff *skb = rx->skb; 405 406 if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN))) 407 return RX_CONTINUE; 408 409 if (test_bit(SCAN_HW_SCANNING, &local->scanning) || 410 test_bit(SCAN_SW_SCANNING, &local->scanning)) 411 return ieee80211_scan_rx(rx->sdata, skb); 412 413 /* scanning finished during invoking of handlers */ 414 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 415 return RX_DROP_UNUSABLE; 416 } 417 418 419 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) 420 { 421 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 422 423 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) 424 return 0; 425 426 return ieee80211_is_robust_mgmt_frame(hdr); 427 } 428 429 430 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) 431 { 432 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 433 434 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) 435 return 0; 436 437 return ieee80211_is_robust_mgmt_frame(hdr); 438 } 439 440 441 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ 442 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) 443 { 444 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; 445 struct ieee80211_mmie *mmie; 446 447 if (skb->len < 24 + sizeof(*mmie) || 448 !is_multicast_ether_addr(hdr->da)) 449 return -1; 450 451 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) 452 return -1; /* not a robust management frame */ 453 454 mmie = (struct ieee80211_mmie *) 455 (skb->data + skb->len - sizeof(*mmie)); 456 if (mmie->element_id != WLAN_EID_MMIE || 457 mmie->length != sizeof(*mmie) - 2) 458 return -1; 459 460 return le16_to_cpu(mmie->key_id); 461 } 462 463 464 static ieee80211_rx_result 465 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 466 { 467 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 468 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 469 char *dev_addr = rx->sdata->vif.addr; 470 471 if (ieee80211_is_data(hdr->frame_control)) { 472 if (is_multicast_ether_addr(hdr->addr1)) { 473 if (ieee80211_has_tods(hdr->frame_control) || 474 !ieee80211_has_fromds(hdr->frame_control)) 475 return RX_DROP_MONITOR; 476 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0) 477 return RX_DROP_MONITOR; 478 } else { 479 if (!ieee80211_has_a4(hdr->frame_control)) 480 return RX_DROP_MONITOR; 481 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0) 482 return RX_DROP_MONITOR; 483 } 484 } 485 486 /* If there is not an established peer link and this is not a peer link 487 * establisment frame, beacon or probe, drop the frame. 488 */ 489 490 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 491 struct ieee80211_mgmt *mgmt; 492 493 if (!ieee80211_is_mgmt(hdr->frame_control)) 494 return RX_DROP_MONITOR; 495 496 if (ieee80211_is_action(hdr->frame_control)) { 497 mgmt = (struct ieee80211_mgmt *)hdr; 498 if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK) 499 return RX_DROP_MONITOR; 500 return RX_CONTINUE; 501 } 502 503 if (ieee80211_is_probe_req(hdr->frame_control) || 504 ieee80211_is_probe_resp(hdr->frame_control) || 505 ieee80211_is_beacon(hdr->frame_control)) 506 return RX_CONTINUE; 507 508 return RX_DROP_MONITOR; 509 510 } 511 512 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 513 514 if (ieee80211_is_data(hdr->frame_control) && 515 is_multicast_ether_addr(hdr->addr1) && 516 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata)) 517 return RX_DROP_MONITOR; 518 #undef msh_h_get 519 520 return RX_CONTINUE; 521 } 522 523 #define SEQ_MODULO 0x1000 524 #define SEQ_MASK 0xfff 525 526 static inline int seq_less(u16 sq1, u16 sq2) 527 { 528 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); 529 } 530 531 static inline u16 seq_inc(u16 sq) 532 { 533 return (sq + 1) & SEQ_MASK; 534 } 535 536 static inline u16 seq_sub(u16 sq1, u16 sq2) 537 { 538 return (sq1 - sq2) & SEQ_MASK; 539 } 540 541 542 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, 543 struct tid_ampdu_rx *tid_agg_rx, 544 int index) 545 { 546 struct ieee80211_local *local = hw_to_local(hw); 547 struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; 548 struct ieee80211_rx_status *status; 549 550 lockdep_assert_held(&tid_agg_rx->reorder_lock); 551 552 if (!skb) 553 goto no_frame; 554 555 /* release the frame from the reorder ring buffer */ 556 tid_agg_rx->stored_mpdu_num--; 557 tid_agg_rx->reorder_buf[index] = NULL; 558 status = IEEE80211_SKB_RXCB(skb); 559 status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE; 560 skb_queue_tail(&local->rx_skb_queue, skb); 561 562 no_frame: 563 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 564 } 565 566 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw, 567 struct tid_ampdu_rx *tid_agg_rx, 568 u16 head_seq_num) 569 { 570 int index; 571 572 lockdep_assert_held(&tid_agg_rx->reorder_lock); 573 574 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 575 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 576 tid_agg_rx->buf_size; 577 ieee80211_release_reorder_frame(hw, tid_agg_rx, index); 578 } 579 } 580 581 /* 582 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If 583 * the skb was added to the buffer longer than this time ago, the earlier 584 * frames that have not yet been received are assumed to be lost and the skb 585 * can be released for processing. This may also release other skb's from the 586 * reorder buffer if there are no additional gaps between the frames. 587 * 588 * Callers must hold tid_agg_rx->reorder_lock. 589 */ 590 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) 591 592 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw, 593 struct tid_ampdu_rx *tid_agg_rx) 594 { 595 int index, j; 596 597 lockdep_assert_held(&tid_agg_rx->reorder_lock); 598 599 /* release the buffer until next missing frame */ 600 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 601 tid_agg_rx->buf_size; 602 if (!tid_agg_rx->reorder_buf[index] && 603 tid_agg_rx->stored_mpdu_num > 1) { 604 /* 605 * No buffers ready to be released, but check whether any 606 * frames in the reorder buffer have timed out. 607 */ 608 int skipped = 1; 609 for (j = (index + 1) % tid_agg_rx->buf_size; j != index; 610 j = (j + 1) % tid_agg_rx->buf_size) { 611 if (!tid_agg_rx->reorder_buf[j]) { 612 skipped++; 613 continue; 614 } 615 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + 616 HT_RX_REORDER_BUF_TIMEOUT)) 617 goto set_release_timer; 618 619 #ifdef CONFIG_MAC80211_HT_DEBUG 620 if (net_ratelimit()) 621 wiphy_debug(hw->wiphy, 622 "release an RX reorder frame due to timeout on earlier frames\n"); 623 #endif 624 ieee80211_release_reorder_frame(hw, tid_agg_rx, j); 625 626 /* 627 * Increment the head seq# also for the skipped slots. 628 */ 629 tid_agg_rx->head_seq_num = 630 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK; 631 skipped = 0; 632 } 633 } else while (tid_agg_rx->reorder_buf[index]) { 634 ieee80211_release_reorder_frame(hw, tid_agg_rx, index); 635 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 636 tid_agg_rx->buf_size; 637 } 638 639 if (tid_agg_rx->stored_mpdu_num) { 640 j = index = seq_sub(tid_agg_rx->head_seq_num, 641 tid_agg_rx->ssn) % tid_agg_rx->buf_size; 642 643 for (; j != (index - 1) % tid_agg_rx->buf_size; 644 j = (j + 1) % tid_agg_rx->buf_size) { 645 if (tid_agg_rx->reorder_buf[j]) 646 break; 647 } 648 649 set_release_timer: 650 651 mod_timer(&tid_agg_rx->reorder_timer, 652 tid_agg_rx->reorder_time[j] + 653 HT_RX_REORDER_BUF_TIMEOUT); 654 } else { 655 del_timer(&tid_agg_rx->reorder_timer); 656 } 657 } 658 659 /* 660 * As this function belongs to the RX path it must be under 661 * rcu_read_lock protection. It returns false if the frame 662 * can be processed immediately, true if it was consumed. 663 */ 664 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 665 struct tid_ampdu_rx *tid_agg_rx, 666 struct sk_buff *skb) 667 { 668 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 669 u16 sc = le16_to_cpu(hdr->seq_ctrl); 670 u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 671 u16 head_seq_num, buf_size; 672 int index; 673 bool ret = true; 674 675 spin_lock(&tid_agg_rx->reorder_lock); 676 677 buf_size = tid_agg_rx->buf_size; 678 head_seq_num = tid_agg_rx->head_seq_num; 679 680 /* frame with out of date sequence number */ 681 if (seq_less(mpdu_seq_num, head_seq_num)) { 682 dev_kfree_skb(skb); 683 goto out; 684 } 685 686 /* 687 * If frame the sequence number exceeds our buffering window 688 * size release some previous frames to make room for this one. 689 */ 690 if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) { 691 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size)); 692 /* release stored frames up to new head to stack */ 693 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num); 694 } 695 696 /* Now the new frame is always in the range of the reordering buffer */ 697 698 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; 699 700 /* check if we already stored this frame */ 701 if (tid_agg_rx->reorder_buf[index]) { 702 dev_kfree_skb(skb); 703 goto out; 704 } 705 706 /* 707 * If the current MPDU is in the right order and nothing else 708 * is stored we can process it directly, no need to buffer it. 709 */ 710 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 711 tid_agg_rx->stored_mpdu_num == 0) { 712 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 713 ret = false; 714 goto out; 715 } 716 717 /* put the frame in the reordering buffer */ 718 tid_agg_rx->reorder_buf[index] = skb; 719 tid_agg_rx->reorder_time[index] = jiffies; 720 tid_agg_rx->stored_mpdu_num++; 721 ieee80211_sta_reorder_release(hw, tid_agg_rx); 722 723 out: 724 spin_unlock(&tid_agg_rx->reorder_lock); 725 return ret; 726 } 727 728 /* 729 * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns 730 * true if the MPDU was buffered, false if it should be processed. 731 */ 732 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx) 733 { 734 struct sk_buff *skb = rx->skb; 735 struct ieee80211_local *local = rx->local; 736 struct ieee80211_hw *hw = &local->hw; 737 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 738 struct sta_info *sta = rx->sta; 739 struct tid_ampdu_rx *tid_agg_rx; 740 u16 sc; 741 int tid; 742 743 if (!ieee80211_is_data_qos(hdr->frame_control)) 744 goto dont_reorder; 745 746 /* 747 * filter the QoS data rx stream according to 748 * STA/TID and check if this STA/TID is on aggregation 749 */ 750 751 if (!sta) 752 goto dont_reorder; 753 754 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 755 756 tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 757 if (!tid_agg_rx) 758 goto dont_reorder; 759 760 /* qos null data frames are excluded */ 761 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 762 goto dont_reorder; 763 764 /* new, potentially un-ordered, ampdu frame - process it */ 765 766 /* reset session timer */ 767 if (tid_agg_rx->timeout) 768 mod_timer(&tid_agg_rx->session_timer, 769 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 770 771 /* if this mpdu is fragmented - terminate rx aggregation session */ 772 sc = le16_to_cpu(hdr->seq_ctrl); 773 if (sc & IEEE80211_SCTL_FRAG) { 774 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 775 skb_queue_tail(&rx->sdata->skb_queue, skb); 776 ieee80211_queue_work(&local->hw, &rx->sdata->work); 777 return; 778 } 779 780 /* 781 * No locking needed -- we will only ever process one 782 * RX packet at a time, and thus own tid_agg_rx. All 783 * other code manipulating it needs to (and does) make 784 * sure that we cannot get to it any more before doing 785 * anything with it. 786 */ 787 if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb)) 788 return; 789 790 dont_reorder: 791 skb_queue_tail(&local->rx_skb_queue, skb); 792 } 793 794 static ieee80211_rx_result debug_noinline 795 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 796 { 797 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 798 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 799 800 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 801 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 802 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 803 rx->sta->last_seq_ctrl[rx->queue] == 804 hdr->seq_ctrl)) { 805 if (status->rx_flags & IEEE80211_RX_RA_MATCH) { 806 rx->local->dot11FrameDuplicateCount++; 807 rx->sta->num_duplicates++; 808 } 809 return RX_DROP_UNUSABLE; 810 } else 811 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 812 } 813 814 if (unlikely(rx->skb->len < 16)) { 815 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 816 return RX_DROP_MONITOR; 817 } 818 819 /* Drop disallowed frame classes based on STA auth/assoc state; 820 * IEEE 802.11, Chap 5.5. 821 * 822 * mac80211 filters only based on association state, i.e. it drops 823 * Class 3 frames from not associated stations. hostapd sends 824 * deauth/disassoc frames when needed. In addition, hostapd is 825 * responsible for filtering on both auth and assoc states. 826 */ 827 828 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 829 return ieee80211_rx_mesh_check(rx); 830 831 if (unlikely((ieee80211_is_data(hdr->frame_control) || 832 ieee80211_is_pspoll(hdr->frame_control)) && 833 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 834 rx->sdata->vif.type != NL80211_IFTYPE_WDS && 835 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) 836 return RX_DROP_MONITOR; 837 838 return RX_CONTINUE; 839 } 840 841 842 static ieee80211_rx_result debug_noinline 843 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 844 { 845 struct sk_buff *skb = rx->skb; 846 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 847 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 848 int keyidx; 849 int hdrlen; 850 ieee80211_rx_result result = RX_DROP_UNUSABLE; 851 struct ieee80211_key *sta_ptk = NULL; 852 int mmie_keyidx = -1; 853 __le16 fc; 854 855 /* 856 * Key selection 101 857 * 858 * There are four types of keys: 859 * - GTK (group keys) 860 * - IGTK (group keys for management frames) 861 * - PTK (pairwise keys) 862 * - STK (station-to-station pairwise keys) 863 * 864 * When selecting a key, we have to distinguish between multicast 865 * (including broadcast) and unicast frames, the latter can only 866 * use PTKs and STKs while the former always use GTKs and IGTKs. 867 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 868 * unicast frames can also use key indices like GTKs. Hence, if we 869 * don't have a PTK/STK we check the key index for a WEP key. 870 * 871 * Note that in a regular BSS, multicast frames are sent by the 872 * AP only, associated stations unicast the frame to the AP first 873 * which then multicasts it on their behalf. 874 * 875 * There is also a slight problem in IBSS mode: GTKs are negotiated 876 * with each station, that is something we don't currently handle. 877 * The spec seems to expect that one negotiates the same key with 878 * every station but there's no such requirement; VLANs could be 879 * possible. 880 */ 881 882 /* 883 * No point in finding a key and decrypting if the frame is neither 884 * addressed to us nor a multicast frame. 885 */ 886 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 887 return RX_CONTINUE; 888 889 /* start without a key */ 890 rx->key = NULL; 891 892 if (rx->sta) 893 sta_ptk = rcu_dereference(rx->sta->ptk); 894 895 fc = hdr->frame_control; 896 897 if (!ieee80211_has_protected(fc)) 898 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 899 900 if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) { 901 rx->key = sta_ptk; 902 if ((status->flag & RX_FLAG_DECRYPTED) && 903 (status->flag & RX_FLAG_IV_STRIPPED)) 904 return RX_CONTINUE; 905 /* Skip decryption if the frame is not protected. */ 906 if (!ieee80211_has_protected(fc)) 907 return RX_CONTINUE; 908 } else if (mmie_keyidx >= 0) { 909 /* Broadcast/multicast robust management frame / BIP */ 910 if ((status->flag & RX_FLAG_DECRYPTED) && 911 (status->flag & RX_FLAG_IV_STRIPPED)) 912 return RX_CONTINUE; 913 914 if (mmie_keyidx < NUM_DEFAULT_KEYS || 915 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 916 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 917 if (rx->sta) 918 rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]); 919 if (!rx->key) 920 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 921 } else if (!ieee80211_has_protected(fc)) { 922 /* 923 * The frame was not protected, so skip decryption. However, we 924 * need to set rx->key if there is a key that could have been 925 * used so that the frame may be dropped if encryption would 926 * have been expected. 927 */ 928 struct ieee80211_key *key = NULL; 929 struct ieee80211_sub_if_data *sdata = rx->sdata; 930 int i; 931 932 if (ieee80211_is_mgmt(fc) && 933 is_multicast_ether_addr(hdr->addr1) && 934 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 935 rx->key = key; 936 else { 937 if (rx->sta) { 938 for (i = 0; i < NUM_DEFAULT_KEYS; i++) { 939 key = rcu_dereference(rx->sta->gtk[i]); 940 if (key) 941 break; 942 } 943 } 944 if (!key) { 945 for (i = 0; i < NUM_DEFAULT_KEYS; i++) { 946 key = rcu_dereference(sdata->keys[i]); 947 if (key) 948 break; 949 } 950 } 951 if (key) 952 rx->key = key; 953 } 954 return RX_CONTINUE; 955 } else { 956 u8 keyid; 957 /* 958 * The device doesn't give us the IV so we won't be 959 * able to look up the key. That's ok though, we 960 * don't need to decrypt the frame, we just won't 961 * be able to keep statistics accurate. 962 * Except for key threshold notifications, should 963 * we somehow allow the driver to tell us which key 964 * the hardware used if this flag is set? 965 */ 966 if ((status->flag & RX_FLAG_DECRYPTED) && 967 (status->flag & RX_FLAG_IV_STRIPPED)) 968 return RX_CONTINUE; 969 970 hdrlen = ieee80211_hdrlen(fc); 971 972 if (rx->skb->len < 8 + hdrlen) 973 return RX_DROP_UNUSABLE; /* TODO: count this? */ 974 975 /* 976 * no need to call ieee80211_wep_get_keyidx, 977 * it verifies a bunch of things we've done already 978 */ 979 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1); 980 keyidx = keyid >> 6; 981 982 /* check per-station GTK first, if multicast packet */ 983 if (is_multicast_ether_addr(hdr->addr1) && rx->sta) 984 rx->key = rcu_dereference(rx->sta->gtk[keyidx]); 985 986 /* if not found, try default key */ 987 if (!rx->key) { 988 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 989 990 /* 991 * RSNA-protected unicast frames should always be 992 * sent with pairwise or station-to-station keys, 993 * but for WEP we allow using a key index as well. 994 */ 995 if (rx->key && 996 rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 && 997 rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 && 998 !is_multicast_ether_addr(hdr->addr1)) 999 rx->key = NULL; 1000 } 1001 } 1002 1003 if (rx->key) { 1004 rx->key->tx_rx_count++; 1005 /* TODO: add threshold stuff again */ 1006 } else { 1007 return RX_DROP_MONITOR; 1008 } 1009 1010 if (skb_linearize(rx->skb)) 1011 return RX_DROP_UNUSABLE; 1012 /* the hdr variable is invalid now! */ 1013 1014 switch (rx->key->conf.cipher) { 1015 case WLAN_CIPHER_SUITE_WEP40: 1016 case WLAN_CIPHER_SUITE_WEP104: 1017 /* Check for weak IVs if possible */ 1018 if (rx->sta && ieee80211_is_data(fc) && 1019 (!(status->flag & RX_FLAG_IV_STRIPPED) || 1020 !(status->flag & RX_FLAG_DECRYPTED)) && 1021 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 1022 rx->sta->wep_weak_iv_count++; 1023 1024 result = ieee80211_crypto_wep_decrypt(rx); 1025 break; 1026 case WLAN_CIPHER_SUITE_TKIP: 1027 result = ieee80211_crypto_tkip_decrypt(rx); 1028 break; 1029 case WLAN_CIPHER_SUITE_CCMP: 1030 result = ieee80211_crypto_ccmp_decrypt(rx); 1031 break; 1032 case WLAN_CIPHER_SUITE_AES_CMAC: 1033 result = ieee80211_crypto_aes_cmac_decrypt(rx); 1034 break; 1035 default: 1036 /* 1037 * We can reach here only with HW-only algorithms 1038 * but why didn't it decrypt the frame?! 1039 */ 1040 return RX_DROP_UNUSABLE; 1041 } 1042 1043 /* either the frame has been decrypted or will be dropped */ 1044 status->flag |= RX_FLAG_DECRYPTED; 1045 1046 return result; 1047 } 1048 1049 static ieee80211_rx_result debug_noinline 1050 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 1051 { 1052 struct ieee80211_local *local; 1053 struct ieee80211_hdr *hdr; 1054 struct sk_buff *skb; 1055 1056 local = rx->local; 1057 skb = rx->skb; 1058 hdr = (struct ieee80211_hdr *) skb->data; 1059 1060 if (!local->pspolling) 1061 return RX_CONTINUE; 1062 1063 if (!ieee80211_has_fromds(hdr->frame_control)) 1064 /* this is not from AP */ 1065 return RX_CONTINUE; 1066 1067 if (!ieee80211_is_data(hdr->frame_control)) 1068 return RX_CONTINUE; 1069 1070 if (!ieee80211_has_moredata(hdr->frame_control)) { 1071 /* AP has no more frames buffered for us */ 1072 local->pspolling = false; 1073 return RX_CONTINUE; 1074 } 1075 1076 /* more data bit is set, let's request a new frame from the AP */ 1077 ieee80211_send_pspoll(local, rx->sdata); 1078 1079 return RX_CONTINUE; 1080 } 1081 1082 static void ap_sta_ps_start(struct sta_info *sta) 1083 { 1084 struct ieee80211_sub_if_data *sdata = sta->sdata; 1085 struct ieee80211_local *local = sdata->local; 1086 1087 atomic_inc(&sdata->bss->num_sta_ps); 1088 set_sta_flags(sta, WLAN_STA_PS_STA); 1089 if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) 1090 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); 1091 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1092 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 1093 sdata->name, sta->sta.addr, sta->sta.aid); 1094 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1095 } 1096 1097 static void ap_sta_ps_end(struct sta_info *sta) 1098 { 1099 struct ieee80211_sub_if_data *sdata = sta->sdata; 1100 1101 atomic_dec(&sdata->bss->num_sta_ps); 1102 1103 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1104 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 1105 sdata->name, sta->sta.addr, sta->sta.aid); 1106 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1107 1108 if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) { 1109 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1110 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", 1111 sdata->name, sta->sta.addr, sta->sta.aid); 1112 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1113 return; 1114 } 1115 1116 ieee80211_sta_ps_deliver_wakeup(sta); 1117 } 1118 1119 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start) 1120 { 1121 struct sta_info *sta_inf = container_of(sta, struct sta_info, sta); 1122 bool in_ps; 1123 1124 WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS)); 1125 1126 /* Don't let the same PS state be set twice */ 1127 in_ps = test_sta_flags(sta_inf, WLAN_STA_PS_STA); 1128 if ((start && in_ps) || (!start && !in_ps)) 1129 return -EINVAL; 1130 1131 if (start) 1132 ap_sta_ps_start(sta_inf); 1133 else 1134 ap_sta_ps_end(sta_inf); 1135 1136 return 0; 1137 } 1138 EXPORT_SYMBOL(ieee80211_sta_ps_transition); 1139 1140 static ieee80211_rx_result debug_noinline 1141 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 1142 { 1143 struct sta_info *sta = rx->sta; 1144 struct sk_buff *skb = rx->skb; 1145 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1146 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1147 1148 if (!sta) 1149 return RX_CONTINUE; 1150 1151 /* 1152 * Update last_rx only for IBSS packets which are for the current 1153 * BSSID to avoid keeping the current IBSS network alive in cases 1154 * where other STAs start using different BSSID. 1155 */ 1156 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 1157 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 1158 NL80211_IFTYPE_ADHOC); 1159 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) { 1160 sta->last_rx = jiffies; 1161 if (ieee80211_is_data(hdr->frame_control)) { 1162 sta->last_rx_rate_idx = status->rate_idx; 1163 sta->last_rx_rate_flag = status->flag; 1164 } 1165 } 1166 } else if (!is_multicast_ether_addr(hdr->addr1)) { 1167 /* 1168 * Mesh beacons will update last_rx when if they are found to 1169 * match the current local configuration when processed. 1170 */ 1171 sta->last_rx = jiffies; 1172 if (ieee80211_is_data(hdr->frame_control)) { 1173 sta->last_rx_rate_idx = status->rate_idx; 1174 sta->last_rx_rate_flag = status->flag; 1175 } 1176 } 1177 1178 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 1179 return RX_CONTINUE; 1180 1181 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 1182 ieee80211_sta_rx_notify(rx->sdata, hdr); 1183 1184 sta->rx_fragments++; 1185 sta->rx_bytes += rx->skb->len; 1186 sta->last_signal = status->signal; 1187 ewma_add(&sta->avg_signal, -status->signal); 1188 1189 /* 1190 * Change STA power saving mode only at the end of a frame 1191 * exchange sequence. 1192 */ 1193 if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) && 1194 !ieee80211_has_morefrags(hdr->frame_control) && 1195 !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) && 1196 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1197 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 1198 if (test_sta_flags(sta, WLAN_STA_PS_STA)) { 1199 /* 1200 * Ignore doze->wake transitions that are 1201 * indicated by non-data frames, the standard 1202 * is unclear here, but for example going to 1203 * PS mode and then scanning would cause a 1204 * doze->wake transition for the probe request, 1205 * and that is clearly undesirable. 1206 */ 1207 if (ieee80211_is_data(hdr->frame_control) && 1208 !ieee80211_has_pm(hdr->frame_control)) 1209 ap_sta_ps_end(sta); 1210 } else { 1211 if (ieee80211_has_pm(hdr->frame_control)) 1212 ap_sta_ps_start(sta); 1213 } 1214 } 1215 1216 /* 1217 * Drop (qos-)data::nullfunc frames silently, since they 1218 * are used only to control station power saving mode. 1219 */ 1220 if (ieee80211_is_nullfunc(hdr->frame_control) || 1221 ieee80211_is_qos_nullfunc(hdr->frame_control)) { 1222 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 1223 1224 /* 1225 * If we receive a 4-addr nullfunc frame from a STA 1226 * that was not moved to a 4-addr STA vlan yet, drop 1227 * the frame to the monitor interface, to make sure 1228 * that hostapd sees it 1229 */ 1230 if (ieee80211_has_a4(hdr->frame_control) && 1231 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1232 (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1233 !rx->sdata->u.vlan.sta))) 1234 return RX_DROP_MONITOR; 1235 /* 1236 * Update counter and free packet here to avoid 1237 * counting this as a dropped packed. 1238 */ 1239 sta->rx_packets++; 1240 dev_kfree_skb(rx->skb); 1241 return RX_QUEUED; 1242 } 1243 1244 return RX_CONTINUE; 1245 } /* ieee80211_rx_h_sta_process */ 1246 1247 static inline struct ieee80211_fragment_entry * 1248 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 1249 unsigned int frag, unsigned int seq, int rx_queue, 1250 struct sk_buff **skb) 1251 { 1252 struct ieee80211_fragment_entry *entry; 1253 int idx; 1254 1255 idx = sdata->fragment_next; 1256 entry = &sdata->fragments[sdata->fragment_next++]; 1257 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 1258 sdata->fragment_next = 0; 1259 1260 if (!skb_queue_empty(&entry->skb_list)) { 1261 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1262 struct ieee80211_hdr *hdr = 1263 (struct ieee80211_hdr *) entry->skb_list.next->data; 1264 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 1265 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 1266 "addr1=%pM addr2=%pM\n", 1267 sdata->name, idx, 1268 jiffies - entry->first_frag_time, entry->seq, 1269 entry->last_frag, hdr->addr1, hdr->addr2); 1270 #endif 1271 __skb_queue_purge(&entry->skb_list); 1272 } 1273 1274 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 1275 *skb = NULL; 1276 entry->first_frag_time = jiffies; 1277 entry->seq = seq; 1278 entry->rx_queue = rx_queue; 1279 entry->last_frag = frag; 1280 entry->ccmp = 0; 1281 entry->extra_len = 0; 1282 1283 return entry; 1284 } 1285 1286 static inline struct ieee80211_fragment_entry * 1287 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 1288 unsigned int frag, unsigned int seq, 1289 int rx_queue, struct ieee80211_hdr *hdr) 1290 { 1291 struct ieee80211_fragment_entry *entry; 1292 int i, idx; 1293 1294 idx = sdata->fragment_next; 1295 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 1296 struct ieee80211_hdr *f_hdr; 1297 1298 idx--; 1299 if (idx < 0) 1300 idx = IEEE80211_FRAGMENT_MAX - 1; 1301 1302 entry = &sdata->fragments[idx]; 1303 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 1304 entry->rx_queue != rx_queue || 1305 entry->last_frag + 1 != frag) 1306 continue; 1307 1308 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 1309 1310 /* 1311 * Check ftype and addresses are equal, else check next fragment 1312 */ 1313 if (((hdr->frame_control ^ f_hdr->frame_control) & 1314 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 1315 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 1316 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 1317 continue; 1318 1319 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 1320 __skb_queue_purge(&entry->skb_list); 1321 continue; 1322 } 1323 return entry; 1324 } 1325 1326 return NULL; 1327 } 1328 1329 static ieee80211_rx_result debug_noinline 1330 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 1331 { 1332 struct ieee80211_hdr *hdr; 1333 u16 sc; 1334 __le16 fc; 1335 unsigned int frag, seq; 1336 struct ieee80211_fragment_entry *entry; 1337 struct sk_buff *skb; 1338 struct ieee80211_rx_status *status; 1339 1340 hdr = (struct ieee80211_hdr *)rx->skb->data; 1341 fc = hdr->frame_control; 1342 sc = le16_to_cpu(hdr->seq_ctrl); 1343 frag = sc & IEEE80211_SCTL_FRAG; 1344 1345 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1346 (rx->skb)->len < 24 || 1347 is_multicast_ether_addr(hdr->addr1))) { 1348 /* not fragmented */ 1349 goto out; 1350 } 1351 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1352 1353 if (skb_linearize(rx->skb)) 1354 return RX_DROP_UNUSABLE; 1355 1356 /* 1357 * skb_linearize() might change the skb->data and 1358 * previously cached variables (in this case, hdr) need to 1359 * be refreshed with the new data. 1360 */ 1361 hdr = (struct ieee80211_hdr *)rx->skb->data; 1362 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1363 1364 if (frag == 0) { 1365 /* This is the first fragment of a new frame. */ 1366 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1367 rx->queue, &(rx->skb)); 1368 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP && 1369 ieee80211_has_protected(fc)) { 1370 int queue = ieee80211_is_mgmt(fc) ? 1371 NUM_RX_DATA_QUEUES : rx->queue; 1372 /* Store CCMP PN so that we can verify that the next 1373 * fragment has a sequential PN value. */ 1374 entry->ccmp = 1; 1375 memcpy(entry->last_pn, 1376 rx->key->u.ccmp.rx_pn[queue], 1377 CCMP_PN_LEN); 1378 } 1379 return RX_QUEUED; 1380 } 1381 1382 /* This is a fragment for a frame that should already be pending in 1383 * fragment cache. Add this fragment to the end of the pending entry. 1384 */ 1385 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1386 if (!entry) { 1387 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1388 return RX_DROP_MONITOR; 1389 } 1390 1391 /* Verify that MPDUs within one MSDU have sequential PN values. 1392 * (IEEE 802.11i, 8.3.3.4.5) */ 1393 if (entry->ccmp) { 1394 int i; 1395 u8 pn[CCMP_PN_LEN], *rpn; 1396 int queue; 1397 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP) 1398 return RX_DROP_UNUSABLE; 1399 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1400 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1401 pn[i]++; 1402 if (pn[i]) 1403 break; 1404 } 1405 queue = ieee80211_is_mgmt(fc) ? 1406 NUM_RX_DATA_QUEUES : rx->queue; 1407 rpn = rx->key->u.ccmp.rx_pn[queue]; 1408 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1409 return RX_DROP_UNUSABLE; 1410 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1411 } 1412 1413 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1414 __skb_queue_tail(&entry->skb_list, rx->skb); 1415 entry->last_frag = frag; 1416 entry->extra_len += rx->skb->len; 1417 if (ieee80211_has_morefrags(fc)) { 1418 rx->skb = NULL; 1419 return RX_QUEUED; 1420 } 1421 1422 rx->skb = __skb_dequeue(&entry->skb_list); 1423 if (skb_tailroom(rx->skb) < entry->extra_len) { 1424 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1425 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1426 GFP_ATOMIC))) { 1427 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1428 __skb_queue_purge(&entry->skb_list); 1429 return RX_DROP_UNUSABLE; 1430 } 1431 } 1432 while ((skb = __skb_dequeue(&entry->skb_list))) { 1433 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1434 dev_kfree_skb(skb); 1435 } 1436 1437 /* Complete frame has been reassembled - process it now */ 1438 status = IEEE80211_SKB_RXCB(rx->skb); 1439 status->rx_flags |= IEEE80211_RX_FRAGMENTED; 1440 1441 out: 1442 if (rx->sta) 1443 rx->sta->rx_packets++; 1444 if (is_multicast_ether_addr(hdr->addr1)) 1445 rx->local->dot11MulticastReceivedFrameCount++; 1446 else 1447 ieee80211_led_rx(rx->local); 1448 return RX_CONTINUE; 1449 } 1450 1451 static ieee80211_rx_result debug_noinline 1452 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1453 { 1454 struct ieee80211_sub_if_data *sdata = rx->sdata; 1455 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1456 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1457 1458 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1459 !(status->rx_flags & IEEE80211_RX_RA_MATCH))) 1460 return RX_CONTINUE; 1461 1462 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1463 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1464 return RX_DROP_UNUSABLE; 1465 1466 if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) 1467 ieee80211_sta_ps_deliver_poll_response(rx->sta); 1468 else 1469 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1470 1471 /* Free PS Poll skb here instead of returning RX_DROP that would 1472 * count as an dropped frame. */ 1473 dev_kfree_skb(rx->skb); 1474 1475 return RX_QUEUED; 1476 } 1477 1478 static ieee80211_rx_result debug_noinline 1479 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1480 { 1481 u8 *data = rx->skb->data; 1482 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1483 1484 if (!ieee80211_is_data_qos(hdr->frame_control)) 1485 return RX_CONTINUE; 1486 1487 /* remove the qos control field, update frame type and meta-data */ 1488 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1489 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1490 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1491 /* change frame type to non QOS */ 1492 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1493 1494 return RX_CONTINUE; 1495 } 1496 1497 static int 1498 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1499 { 1500 if (unlikely(!rx->sta || 1501 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1502 return -EACCES; 1503 1504 return 0; 1505 } 1506 1507 static int 1508 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1509 { 1510 struct sk_buff *skb = rx->skb; 1511 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1512 1513 /* 1514 * Pass through unencrypted frames if the hardware has 1515 * decrypted them already. 1516 */ 1517 if (status->flag & RX_FLAG_DECRYPTED) 1518 return 0; 1519 1520 /* Drop unencrypted frames if key is set. */ 1521 if (unlikely(!ieee80211_has_protected(fc) && 1522 !ieee80211_is_nullfunc(fc) && 1523 ieee80211_is_data(fc) && 1524 (rx->key || rx->sdata->drop_unencrypted))) 1525 return -EACCES; 1526 1527 return 0; 1528 } 1529 1530 static int 1531 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) 1532 { 1533 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1534 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1535 __le16 fc = hdr->frame_control; 1536 1537 /* 1538 * Pass through unencrypted frames if the hardware has 1539 * decrypted them already. 1540 */ 1541 if (status->flag & RX_FLAG_DECRYPTED) 1542 return 0; 1543 1544 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1545 if (unlikely(!ieee80211_has_protected(fc) && 1546 ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1547 rx->key)) { 1548 if (ieee80211_is_deauth(fc)) 1549 cfg80211_send_unprot_deauth(rx->sdata->dev, 1550 rx->skb->data, 1551 rx->skb->len); 1552 else if (ieee80211_is_disassoc(fc)) 1553 cfg80211_send_unprot_disassoc(rx->sdata->dev, 1554 rx->skb->data, 1555 rx->skb->len); 1556 return -EACCES; 1557 } 1558 /* BIP does not use Protected field, so need to check MMIE */ 1559 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && 1560 ieee80211_get_mmie_keyidx(rx->skb) < 0)) { 1561 if (ieee80211_is_deauth(fc)) 1562 cfg80211_send_unprot_deauth(rx->sdata->dev, 1563 rx->skb->data, 1564 rx->skb->len); 1565 else if (ieee80211_is_disassoc(fc)) 1566 cfg80211_send_unprot_disassoc(rx->sdata->dev, 1567 rx->skb->data, 1568 rx->skb->len); 1569 return -EACCES; 1570 } 1571 /* 1572 * When using MFP, Action frames are not allowed prior to 1573 * having configured keys. 1574 */ 1575 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1576 ieee80211_is_robust_mgmt_frame( 1577 (struct ieee80211_hdr *) rx->skb->data))) 1578 return -EACCES; 1579 } 1580 1581 return 0; 1582 } 1583 1584 static int 1585 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1586 { 1587 struct ieee80211_sub_if_data *sdata = rx->sdata; 1588 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1589 bool check_port_control = false; 1590 struct ethhdr *ehdr; 1591 int ret; 1592 1593 if (ieee80211_has_a4(hdr->frame_control) && 1594 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) 1595 return -1; 1596 1597 if (sdata->vif.type == NL80211_IFTYPE_STATION && 1598 !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) { 1599 1600 if (!sdata->u.mgd.use_4addr) 1601 return -1; 1602 else 1603 check_port_control = true; 1604 } 1605 1606 if (is_multicast_ether_addr(hdr->addr1) && 1607 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) 1608 return -1; 1609 1610 ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); 1611 if (ret < 0 || !check_port_control) 1612 return ret; 1613 1614 ehdr = (struct ethhdr *) rx->skb->data; 1615 if (ehdr->h_proto != rx->sdata->control_port_protocol) 1616 return -1; 1617 1618 return 0; 1619 } 1620 1621 /* 1622 * requires that rx->skb is a frame with ethernet header 1623 */ 1624 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1625 { 1626 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1627 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1628 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1629 1630 /* 1631 * Allow EAPOL frames to us/the PAE group address regardless 1632 * of whether the frame was encrypted or not. 1633 */ 1634 if (ehdr->h_proto == rx->sdata->control_port_protocol && 1635 (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || 1636 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1637 return true; 1638 1639 if (ieee80211_802_1x_port_control(rx) || 1640 ieee80211_drop_unencrypted(rx, fc)) 1641 return false; 1642 1643 return true; 1644 } 1645 1646 /* 1647 * requires that rx->skb is a frame with ethernet header 1648 */ 1649 static void 1650 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1651 { 1652 struct ieee80211_sub_if_data *sdata = rx->sdata; 1653 struct net_device *dev = sdata->dev; 1654 struct sk_buff *skb, *xmit_skb; 1655 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1656 struct sta_info *dsta; 1657 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1658 1659 skb = rx->skb; 1660 xmit_skb = NULL; 1661 1662 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1663 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1664 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1665 (status->rx_flags & IEEE80211_RX_RA_MATCH) && 1666 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { 1667 if (is_multicast_ether_addr(ehdr->h_dest)) { 1668 /* 1669 * send multicast frames both to higher layers in 1670 * local net stack and back to the wireless medium 1671 */ 1672 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1673 if (!xmit_skb && net_ratelimit()) 1674 printk(KERN_DEBUG "%s: failed to clone " 1675 "multicast frame\n", dev->name); 1676 } else { 1677 dsta = sta_info_get(sdata, skb->data); 1678 if (dsta) { 1679 /* 1680 * The destination station is associated to 1681 * this AP (in this VLAN), so send the frame 1682 * directly to it and do not pass it to local 1683 * net stack. 1684 */ 1685 xmit_skb = skb; 1686 skb = NULL; 1687 } 1688 } 1689 } 1690 1691 if (skb) { 1692 int align __maybe_unused; 1693 1694 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1695 /* 1696 * 'align' will only take the values 0 or 2 here 1697 * since all frames are required to be aligned 1698 * to 2-byte boundaries when being passed to 1699 * mac80211. That also explains the __skb_push() 1700 * below. 1701 */ 1702 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1703 if (align) { 1704 if (WARN_ON(skb_headroom(skb) < 3)) { 1705 dev_kfree_skb(skb); 1706 skb = NULL; 1707 } else { 1708 u8 *data = skb->data; 1709 size_t len = skb_headlen(skb); 1710 skb->data -= align; 1711 memmove(skb->data, data, len); 1712 skb_set_tail_pointer(skb, len); 1713 } 1714 } 1715 #endif 1716 1717 if (skb) { 1718 /* deliver to local stack */ 1719 skb->protocol = eth_type_trans(skb, dev); 1720 memset(skb->cb, 0, sizeof(skb->cb)); 1721 netif_receive_skb(skb); 1722 } 1723 } 1724 1725 if (xmit_skb) { 1726 /* send to wireless media */ 1727 xmit_skb->protocol = htons(ETH_P_802_3); 1728 skb_reset_network_header(xmit_skb); 1729 skb_reset_mac_header(xmit_skb); 1730 dev_queue_xmit(xmit_skb); 1731 } 1732 } 1733 1734 static ieee80211_rx_result debug_noinline 1735 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1736 { 1737 struct net_device *dev = rx->sdata->dev; 1738 struct sk_buff *skb = rx->skb; 1739 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1740 __le16 fc = hdr->frame_control; 1741 struct sk_buff_head frame_list; 1742 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1743 1744 if (unlikely(!ieee80211_is_data(fc))) 1745 return RX_CONTINUE; 1746 1747 if (unlikely(!ieee80211_is_data_present(fc))) 1748 return RX_DROP_MONITOR; 1749 1750 if (!(status->rx_flags & IEEE80211_RX_AMSDU)) 1751 return RX_CONTINUE; 1752 1753 if (ieee80211_has_a4(hdr->frame_control) && 1754 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1755 !rx->sdata->u.vlan.sta) 1756 return RX_DROP_UNUSABLE; 1757 1758 if (is_multicast_ether_addr(hdr->addr1) && 1759 ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1760 rx->sdata->u.vlan.sta) || 1761 (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 1762 rx->sdata->u.mgd.use_4addr))) 1763 return RX_DROP_UNUSABLE; 1764 1765 skb->dev = dev; 1766 __skb_queue_head_init(&frame_list); 1767 1768 if (skb_linearize(skb)) 1769 return RX_DROP_UNUSABLE; 1770 1771 ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, 1772 rx->sdata->vif.type, 1773 rx->local->hw.extra_tx_headroom); 1774 1775 while (!skb_queue_empty(&frame_list)) { 1776 rx->skb = __skb_dequeue(&frame_list); 1777 1778 if (!ieee80211_frame_allowed(rx, fc)) { 1779 dev_kfree_skb(rx->skb); 1780 continue; 1781 } 1782 dev->stats.rx_packets++; 1783 dev->stats.rx_bytes += rx->skb->len; 1784 1785 ieee80211_deliver_skb(rx); 1786 } 1787 1788 return RX_QUEUED; 1789 } 1790 1791 #ifdef CONFIG_MAC80211_MESH 1792 static ieee80211_rx_result 1793 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1794 { 1795 struct ieee80211_hdr *hdr; 1796 struct ieee80211s_hdr *mesh_hdr; 1797 unsigned int hdrlen; 1798 struct sk_buff *skb = rx->skb, *fwd_skb; 1799 struct ieee80211_local *local = rx->local; 1800 struct ieee80211_sub_if_data *sdata = rx->sdata; 1801 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1802 1803 hdr = (struct ieee80211_hdr *) skb->data; 1804 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1805 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1806 1807 if (!ieee80211_is_data(hdr->frame_control)) 1808 return RX_CONTINUE; 1809 1810 if (!mesh_hdr->ttl) 1811 /* illegal frame */ 1812 return RX_DROP_MONITOR; 1813 1814 if (mesh_hdr->flags & MESH_FLAGS_AE) { 1815 struct mesh_path *mppath; 1816 char *proxied_addr; 1817 char *mpp_addr; 1818 1819 if (is_multicast_ether_addr(hdr->addr1)) { 1820 mpp_addr = hdr->addr3; 1821 proxied_addr = mesh_hdr->eaddr1; 1822 } else { 1823 mpp_addr = hdr->addr4; 1824 proxied_addr = mesh_hdr->eaddr2; 1825 } 1826 1827 rcu_read_lock(); 1828 mppath = mpp_path_lookup(proxied_addr, sdata); 1829 if (!mppath) { 1830 mpp_path_add(proxied_addr, mpp_addr, sdata); 1831 } else { 1832 spin_lock_bh(&mppath->state_lock); 1833 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) 1834 memcpy(mppath->mpp, mpp_addr, ETH_ALEN); 1835 spin_unlock_bh(&mppath->state_lock); 1836 } 1837 rcu_read_unlock(); 1838 } 1839 1840 /* Frame has reached destination. Don't forward */ 1841 if (!is_multicast_ether_addr(hdr->addr1) && 1842 compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) 1843 return RX_CONTINUE; 1844 1845 mesh_hdr->ttl--; 1846 1847 if (status->rx_flags & IEEE80211_RX_RA_MATCH) { 1848 if (!mesh_hdr->ttl) 1849 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1850 dropped_frames_ttl); 1851 else { 1852 struct ieee80211_hdr *fwd_hdr; 1853 struct ieee80211_tx_info *info; 1854 1855 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1856 1857 if (!fwd_skb && net_ratelimit()) 1858 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1859 sdata->name); 1860 if (!fwd_skb) 1861 goto out; 1862 1863 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1864 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); 1865 info = IEEE80211_SKB_CB(fwd_skb); 1866 memset(info, 0, sizeof(*info)); 1867 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1868 info->control.vif = &rx->sdata->vif; 1869 skb_set_queue_mapping(skb, 1870 ieee80211_select_queue(rx->sdata, fwd_skb)); 1871 ieee80211_set_qos_hdr(local, skb); 1872 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1873 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1874 fwded_mcast); 1875 else { 1876 int err; 1877 /* 1878 * Save TA to addr1 to send TA a path error if a 1879 * suitable next hop is not found 1880 */ 1881 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1882 ETH_ALEN); 1883 err = mesh_nexthop_lookup(fwd_skb, sdata); 1884 /* Failed to immediately resolve next hop: 1885 * fwded frame was dropped or will be added 1886 * later to the pending skb queue. */ 1887 if (err) 1888 return RX_DROP_MONITOR; 1889 1890 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1891 fwded_unicast); 1892 } 1893 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1894 fwded_frames); 1895 ieee80211_add_pending_skb(local, fwd_skb); 1896 } 1897 } 1898 1899 out: 1900 if (is_multicast_ether_addr(hdr->addr1) || 1901 sdata->dev->flags & IFF_PROMISC) 1902 return RX_CONTINUE; 1903 else 1904 return RX_DROP_MONITOR; 1905 } 1906 #endif 1907 1908 static ieee80211_rx_result debug_noinline 1909 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1910 { 1911 struct ieee80211_sub_if_data *sdata = rx->sdata; 1912 struct ieee80211_local *local = rx->local; 1913 struct net_device *dev = sdata->dev; 1914 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1915 __le16 fc = hdr->frame_control; 1916 int err; 1917 1918 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1919 return RX_CONTINUE; 1920 1921 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1922 return RX_DROP_MONITOR; 1923 1924 /* 1925 * Allow the cooked monitor interface of an AP to see 4-addr frames so 1926 * that a 4-addr station can be detected and moved into a separate VLAN 1927 */ 1928 if (ieee80211_has_a4(hdr->frame_control) && 1929 sdata->vif.type == NL80211_IFTYPE_AP) 1930 return RX_DROP_MONITOR; 1931 1932 err = __ieee80211_data_to_8023(rx); 1933 if (unlikely(err)) 1934 return RX_DROP_UNUSABLE; 1935 1936 if (!ieee80211_frame_allowed(rx, fc)) 1937 return RX_DROP_MONITOR; 1938 1939 rx->skb->dev = dev; 1940 1941 dev->stats.rx_packets++; 1942 dev->stats.rx_bytes += rx->skb->len; 1943 1944 if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 && 1945 !is_multicast_ether_addr( 1946 ((struct ethhdr *)rx->skb->data)->h_dest) && 1947 (!local->scanning && 1948 !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) { 1949 mod_timer(&local->dynamic_ps_timer, jiffies + 1950 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1951 } 1952 1953 ieee80211_deliver_skb(rx); 1954 1955 return RX_QUEUED; 1956 } 1957 1958 static ieee80211_rx_result debug_noinline 1959 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx) 1960 { 1961 struct ieee80211_local *local = rx->local; 1962 struct ieee80211_hw *hw = &local->hw; 1963 struct sk_buff *skb = rx->skb; 1964 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1965 struct tid_ampdu_rx *tid_agg_rx; 1966 u16 start_seq_num; 1967 u16 tid; 1968 1969 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1970 return RX_CONTINUE; 1971 1972 if (ieee80211_is_back_req(bar->frame_control)) { 1973 struct { 1974 __le16 control, start_seq_num; 1975 } __packed bar_data; 1976 1977 if (!rx->sta) 1978 return RX_DROP_MONITOR; 1979 1980 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control), 1981 &bar_data, sizeof(bar_data))) 1982 return RX_DROP_MONITOR; 1983 1984 tid = le16_to_cpu(bar_data.control) >> 12; 1985 1986 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]); 1987 if (!tid_agg_rx) 1988 return RX_DROP_MONITOR; 1989 1990 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4; 1991 1992 /* reset session timer */ 1993 if (tid_agg_rx->timeout) 1994 mod_timer(&tid_agg_rx->session_timer, 1995 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1996 1997 spin_lock(&tid_agg_rx->reorder_lock); 1998 /* release stored frames up to start of BAR */ 1999 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num); 2000 spin_unlock(&tid_agg_rx->reorder_lock); 2001 2002 kfree_skb(skb); 2003 return RX_QUEUED; 2004 } 2005 2006 /* 2007 * After this point, we only want management frames, 2008 * so we can drop all remaining control frames to 2009 * cooked monitor interfaces. 2010 */ 2011 return RX_DROP_MONITOR; 2012 } 2013 2014 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 2015 struct ieee80211_mgmt *mgmt, 2016 size_t len) 2017 { 2018 struct ieee80211_local *local = sdata->local; 2019 struct sk_buff *skb; 2020 struct ieee80211_mgmt *resp; 2021 2022 if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { 2023 /* Not to own unicast address */ 2024 return; 2025 } 2026 2027 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 2028 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 2029 /* Not from the current AP or not associated yet. */ 2030 return; 2031 } 2032 2033 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 2034 /* Too short SA Query request frame */ 2035 return; 2036 } 2037 2038 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 2039 if (skb == NULL) 2040 return; 2041 2042 skb_reserve(skb, local->hw.extra_tx_headroom); 2043 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 2044 memset(resp, 0, 24); 2045 memcpy(resp->da, mgmt->sa, ETH_ALEN); 2046 memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); 2047 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 2048 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2049 IEEE80211_STYPE_ACTION); 2050 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 2051 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 2052 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 2053 memcpy(resp->u.action.u.sa_query.trans_id, 2054 mgmt->u.action.u.sa_query.trans_id, 2055 WLAN_SA_QUERY_TR_ID_LEN); 2056 2057 ieee80211_tx_skb(sdata, skb); 2058 } 2059 2060 static ieee80211_rx_result debug_noinline 2061 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx) 2062 { 2063 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2064 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2065 2066 /* 2067 * From here on, look only at management frames. 2068 * Data and control frames are already handled, 2069 * and unknown (reserved) frames are useless. 2070 */ 2071 if (rx->skb->len < 24) 2072 return RX_DROP_MONITOR; 2073 2074 if (!ieee80211_is_mgmt(mgmt->frame_control)) 2075 return RX_DROP_MONITOR; 2076 2077 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 2078 return RX_DROP_MONITOR; 2079 2080 if (ieee80211_drop_unencrypted_mgmt(rx)) 2081 return RX_DROP_UNUSABLE; 2082 2083 return RX_CONTINUE; 2084 } 2085 2086 static ieee80211_rx_result debug_noinline 2087 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 2088 { 2089 struct ieee80211_local *local = rx->local; 2090 struct ieee80211_sub_if_data *sdata = rx->sdata; 2091 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2092 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2093 int len = rx->skb->len; 2094 2095 if (!ieee80211_is_action(mgmt->frame_control)) 2096 return RX_CONTINUE; 2097 2098 /* drop too small frames */ 2099 if (len < IEEE80211_MIN_ACTION_SIZE) 2100 return RX_DROP_UNUSABLE; 2101 2102 if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) 2103 return RX_DROP_UNUSABLE; 2104 2105 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 2106 return RX_DROP_UNUSABLE; 2107 2108 switch (mgmt->u.action.category) { 2109 case WLAN_CATEGORY_BACK: 2110 /* 2111 * The aggregation code is not prepared to handle 2112 * anything but STA/AP due to the BSSID handling; 2113 * IBSS could work in the code but isn't supported 2114 * by drivers or the standard. 2115 */ 2116 if (sdata->vif.type != NL80211_IFTYPE_STATION && 2117 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 2118 sdata->vif.type != NL80211_IFTYPE_AP) 2119 break; 2120 2121 /* verify action_code is present */ 2122 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 2123 break; 2124 2125 switch (mgmt->u.action.u.addba_req.action_code) { 2126 case WLAN_ACTION_ADDBA_REQ: 2127 if (len < (IEEE80211_MIN_ACTION_SIZE + 2128 sizeof(mgmt->u.action.u.addba_req))) 2129 goto invalid; 2130 break; 2131 case WLAN_ACTION_ADDBA_RESP: 2132 if (len < (IEEE80211_MIN_ACTION_SIZE + 2133 sizeof(mgmt->u.action.u.addba_resp))) 2134 goto invalid; 2135 break; 2136 case WLAN_ACTION_DELBA: 2137 if (len < (IEEE80211_MIN_ACTION_SIZE + 2138 sizeof(mgmt->u.action.u.delba))) 2139 goto invalid; 2140 break; 2141 default: 2142 goto invalid; 2143 } 2144 2145 goto queue; 2146 case WLAN_CATEGORY_SPECTRUM_MGMT: 2147 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 2148 break; 2149 2150 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2151 break; 2152 2153 /* verify action_code is present */ 2154 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 2155 break; 2156 2157 switch (mgmt->u.action.u.measurement.action_code) { 2158 case WLAN_ACTION_SPCT_MSR_REQ: 2159 if (len < (IEEE80211_MIN_ACTION_SIZE + 2160 sizeof(mgmt->u.action.u.measurement))) 2161 break; 2162 ieee80211_process_measurement_req(sdata, mgmt, len); 2163 goto handled; 2164 case WLAN_ACTION_SPCT_CHL_SWITCH: 2165 if (len < (IEEE80211_MIN_ACTION_SIZE + 2166 sizeof(mgmt->u.action.u.chan_switch))) 2167 break; 2168 2169 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2170 break; 2171 2172 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 2173 break; 2174 2175 goto queue; 2176 } 2177 break; 2178 case WLAN_CATEGORY_SA_QUERY: 2179 if (len < (IEEE80211_MIN_ACTION_SIZE + 2180 sizeof(mgmt->u.action.u.sa_query))) 2181 break; 2182 2183 switch (mgmt->u.action.u.sa_query.action) { 2184 case WLAN_ACTION_SA_QUERY_REQUEST: 2185 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2186 break; 2187 ieee80211_process_sa_query_req(sdata, mgmt, len); 2188 goto handled; 2189 } 2190 break; 2191 case WLAN_CATEGORY_MESH_PLINK: 2192 if (!ieee80211_vif_is_mesh(&sdata->vif)) 2193 break; 2194 goto queue; 2195 case WLAN_CATEGORY_MESH_PATH_SEL: 2196 if (!mesh_path_sel_is_hwmp(sdata)) 2197 break; 2198 goto queue; 2199 } 2200 2201 return RX_CONTINUE; 2202 2203 invalid: 2204 status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM; 2205 /* will return in the next handlers */ 2206 return RX_CONTINUE; 2207 2208 handled: 2209 if (rx->sta) 2210 rx->sta->rx_packets++; 2211 dev_kfree_skb(rx->skb); 2212 return RX_QUEUED; 2213 2214 queue: 2215 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2216 skb_queue_tail(&sdata->skb_queue, rx->skb); 2217 ieee80211_queue_work(&local->hw, &sdata->work); 2218 if (rx->sta) 2219 rx->sta->rx_packets++; 2220 return RX_QUEUED; 2221 } 2222 2223 static ieee80211_rx_result debug_noinline 2224 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx) 2225 { 2226 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2227 2228 /* skip known-bad action frames and return them in the next handler */ 2229 if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) 2230 return RX_CONTINUE; 2231 2232 /* 2233 * Getting here means the kernel doesn't know how to handle 2234 * it, but maybe userspace does ... include returned frames 2235 * so userspace can register for those to know whether ones 2236 * it transmitted were processed or returned. 2237 */ 2238 2239 if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq, 2240 rx->skb->data, rx->skb->len, 2241 GFP_ATOMIC)) { 2242 if (rx->sta) 2243 rx->sta->rx_packets++; 2244 dev_kfree_skb(rx->skb); 2245 return RX_QUEUED; 2246 } 2247 2248 2249 return RX_CONTINUE; 2250 } 2251 2252 static ieee80211_rx_result debug_noinline 2253 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx) 2254 { 2255 struct ieee80211_local *local = rx->local; 2256 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2257 struct sk_buff *nskb; 2258 struct ieee80211_sub_if_data *sdata = rx->sdata; 2259 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2260 2261 if (!ieee80211_is_action(mgmt->frame_control)) 2262 return RX_CONTINUE; 2263 2264 /* 2265 * For AP mode, hostapd is responsible for handling any action 2266 * frames that we didn't handle, including returning unknown 2267 * ones. For all other modes we will return them to the sender, 2268 * setting the 0x80 bit in the action category, as required by 2269 * 802.11-2007 7.3.1.11. 2270 * Newer versions of hostapd shall also use the management frame 2271 * registration mechanisms, but older ones still use cooked 2272 * monitor interfaces so push all frames there. 2273 */ 2274 if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) && 2275 (sdata->vif.type == NL80211_IFTYPE_AP || 2276 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) 2277 return RX_DROP_MONITOR; 2278 2279 /* do not return rejected action frames */ 2280 if (mgmt->u.action.category & 0x80) 2281 return RX_DROP_UNUSABLE; 2282 2283 nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0, 2284 GFP_ATOMIC); 2285 if (nskb) { 2286 struct ieee80211_mgmt *nmgmt = (void *)nskb->data; 2287 2288 nmgmt->u.action.category |= 0x80; 2289 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN); 2290 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN); 2291 2292 memset(nskb->cb, 0, sizeof(nskb->cb)); 2293 2294 ieee80211_tx_skb(rx->sdata, nskb); 2295 } 2296 dev_kfree_skb(rx->skb); 2297 return RX_QUEUED; 2298 } 2299 2300 static ieee80211_rx_result debug_noinline 2301 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 2302 { 2303 struct ieee80211_sub_if_data *sdata = rx->sdata; 2304 ieee80211_rx_result rxs; 2305 struct ieee80211_mgmt *mgmt = (void *)rx->skb->data; 2306 __le16 stype; 2307 2308 rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); 2309 if (rxs != RX_CONTINUE) 2310 return rxs; 2311 2312 stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE); 2313 2314 if (!ieee80211_vif_is_mesh(&sdata->vif) && 2315 sdata->vif.type != NL80211_IFTYPE_ADHOC && 2316 sdata->vif.type != NL80211_IFTYPE_STATION) 2317 return RX_DROP_MONITOR; 2318 2319 switch (stype) { 2320 case cpu_to_le16(IEEE80211_STYPE_BEACON): 2321 case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP): 2322 /* process for all: mesh, mlme, ibss */ 2323 break; 2324 case cpu_to_le16(IEEE80211_STYPE_DEAUTH): 2325 case cpu_to_le16(IEEE80211_STYPE_DISASSOC): 2326 if (is_multicast_ether_addr(mgmt->da) && 2327 !is_broadcast_ether_addr(mgmt->da)) 2328 return RX_DROP_MONITOR; 2329 2330 /* process only for station */ 2331 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2332 return RX_DROP_MONITOR; 2333 break; 2334 case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ): 2335 case cpu_to_le16(IEEE80211_STYPE_AUTH): 2336 /* process only for ibss */ 2337 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 2338 return RX_DROP_MONITOR; 2339 break; 2340 default: 2341 return RX_DROP_MONITOR; 2342 } 2343 2344 /* queue up frame and kick off work to process it */ 2345 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2346 skb_queue_tail(&sdata->skb_queue, rx->skb); 2347 ieee80211_queue_work(&rx->local->hw, &sdata->work); 2348 if (rx->sta) 2349 rx->sta->rx_packets++; 2350 2351 return RX_QUEUED; 2352 } 2353 2354 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 2355 struct ieee80211_rx_data *rx) 2356 { 2357 int keyidx; 2358 unsigned int hdrlen; 2359 2360 hdrlen = ieee80211_hdrlen(hdr->frame_control); 2361 if (rx->skb->len >= hdrlen + 4) 2362 keyidx = rx->skb->data[hdrlen + 3] >> 6; 2363 else 2364 keyidx = -1; 2365 2366 if (!rx->sta) { 2367 /* 2368 * Some hardware seem to generate incorrect Michael MIC 2369 * reports; ignore them to avoid triggering countermeasures. 2370 */ 2371 return; 2372 } 2373 2374 if (!ieee80211_has_protected(hdr->frame_control)) 2375 return; 2376 2377 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 2378 /* 2379 * APs with pairwise keys should never receive Michael MIC 2380 * errors for non-zero keyidx because these are reserved for 2381 * group keys and only the AP is sending real multicast 2382 * frames in the BSS. 2383 */ 2384 return; 2385 } 2386 2387 if (!ieee80211_is_data(hdr->frame_control) && 2388 !ieee80211_is_auth(hdr->frame_control)) 2389 return; 2390 2391 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 2392 GFP_ATOMIC); 2393 } 2394 2395 /* TODO: use IEEE80211_RX_FRAGMENTED */ 2396 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, 2397 struct ieee80211_rate *rate) 2398 { 2399 struct ieee80211_sub_if_data *sdata; 2400 struct ieee80211_local *local = rx->local; 2401 struct ieee80211_rtap_hdr { 2402 struct ieee80211_radiotap_header hdr; 2403 u8 flags; 2404 u8 rate_or_pad; 2405 __le16 chan_freq; 2406 __le16 chan_flags; 2407 } __packed *rthdr; 2408 struct sk_buff *skb = rx->skb, *skb2; 2409 struct net_device *prev_dev = NULL; 2410 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2411 2412 /* 2413 * If cooked monitor has been processed already, then 2414 * don't do it again. If not, set the flag. 2415 */ 2416 if (rx->flags & IEEE80211_RX_CMNTR) 2417 goto out_free_skb; 2418 rx->flags |= IEEE80211_RX_CMNTR; 2419 2420 if (skb_headroom(skb) < sizeof(*rthdr) && 2421 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 2422 goto out_free_skb; 2423 2424 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 2425 memset(rthdr, 0, sizeof(*rthdr)); 2426 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 2427 rthdr->hdr.it_present = 2428 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 2429 (1 << IEEE80211_RADIOTAP_CHANNEL)); 2430 2431 if (rate) { 2432 rthdr->rate_or_pad = rate->bitrate / 5; 2433 rthdr->hdr.it_present |= 2434 cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 2435 } 2436 rthdr->chan_freq = cpu_to_le16(status->freq); 2437 2438 if (status->band == IEEE80211_BAND_5GHZ) 2439 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 2440 IEEE80211_CHAN_5GHZ); 2441 else 2442 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 2443 IEEE80211_CHAN_2GHZ); 2444 2445 skb_set_mac_header(skb, 0); 2446 skb->ip_summed = CHECKSUM_UNNECESSARY; 2447 skb->pkt_type = PACKET_OTHERHOST; 2448 skb->protocol = htons(ETH_P_802_2); 2449 2450 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2451 if (!ieee80211_sdata_running(sdata)) 2452 continue; 2453 2454 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 2455 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 2456 continue; 2457 2458 if (prev_dev) { 2459 skb2 = skb_clone(skb, GFP_ATOMIC); 2460 if (skb2) { 2461 skb2->dev = prev_dev; 2462 netif_receive_skb(skb2); 2463 } 2464 } 2465 2466 prev_dev = sdata->dev; 2467 sdata->dev->stats.rx_packets++; 2468 sdata->dev->stats.rx_bytes += skb->len; 2469 } 2470 2471 if (prev_dev) { 2472 skb->dev = prev_dev; 2473 netif_receive_skb(skb); 2474 return; 2475 } 2476 2477 out_free_skb: 2478 dev_kfree_skb(skb); 2479 } 2480 2481 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx, 2482 ieee80211_rx_result res) 2483 { 2484 switch (res) { 2485 case RX_DROP_MONITOR: 2486 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); 2487 if (rx->sta) 2488 rx->sta->rx_dropped++; 2489 /* fall through */ 2490 case RX_CONTINUE: { 2491 struct ieee80211_rate *rate = NULL; 2492 struct ieee80211_supported_band *sband; 2493 struct ieee80211_rx_status *status; 2494 2495 status = IEEE80211_SKB_RXCB((rx->skb)); 2496 2497 sband = rx->local->hw.wiphy->bands[status->band]; 2498 if (!(status->flag & RX_FLAG_HT)) 2499 rate = &sband->bitrates[status->rate_idx]; 2500 2501 ieee80211_rx_cooked_monitor(rx, rate); 2502 break; 2503 } 2504 case RX_DROP_UNUSABLE: 2505 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); 2506 if (rx->sta) 2507 rx->sta->rx_dropped++; 2508 dev_kfree_skb(rx->skb); 2509 break; 2510 case RX_QUEUED: 2511 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued); 2512 break; 2513 } 2514 } 2515 2516 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx) 2517 { 2518 ieee80211_rx_result res = RX_DROP_MONITOR; 2519 struct sk_buff *skb; 2520 2521 #define CALL_RXH(rxh) \ 2522 do { \ 2523 res = rxh(rx); \ 2524 if (res != RX_CONTINUE) \ 2525 goto rxh_next; \ 2526 } while (0); 2527 2528 spin_lock(&rx->local->rx_skb_queue.lock); 2529 if (rx->local->running_rx_handler) 2530 goto unlock; 2531 2532 rx->local->running_rx_handler = true; 2533 2534 while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) { 2535 spin_unlock(&rx->local->rx_skb_queue.lock); 2536 2537 /* 2538 * all the other fields are valid across frames 2539 * that belong to an aMPDU since they are on the 2540 * same TID from the same station 2541 */ 2542 rx->skb = skb; 2543 rx->flags = 0; 2544 2545 CALL_RXH(ieee80211_rx_h_decrypt) 2546 CALL_RXH(ieee80211_rx_h_check_more_data) 2547 CALL_RXH(ieee80211_rx_h_sta_process) 2548 CALL_RXH(ieee80211_rx_h_defragment) 2549 CALL_RXH(ieee80211_rx_h_ps_poll) 2550 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 2551 /* must be after MMIC verify so header is counted in MPDU mic */ 2552 CALL_RXH(ieee80211_rx_h_remove_qos_control) 2553 CALL_RXH(ieee80211_rx_h_amsdu) 2554 #ifdef CONFIG_MAC80211_MESH 2555 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 2556 CALL_RXH(ieee80211_rx_h_mesh_fwding); 2557 #endif 2558 CALL_RXH(ieee80211_rx_h_data) 2559 CALL_RXH(ieee80211_rx_h_ctrl); 2560 CALL_RXH(ieee80211_rx_h_mgmt_check) 2561 CALL_RXH(ieee80211_rx_h_action) 2562 CALL_RXH(ieee80211_rx_h_userspace_mgmt) 2563 CALL_RXH(ieee80211_rx_h_action_return) 2564 CALL_RXH(ieee80211_rx_h_mgmt) 2565 2566 rxh_next: 2567 ieee80211_rx_handlers_result(rx, res); 2568 spin_lock(&rx->local->rx_skb_queue.lock); 2569 #undef CALL_RXH 2570 } 2571 2572 rx->local->running_rx_handler = false; 2573 2574 unlock: 2575 spin_unlock(&rx->local->rx_skb_queue.lock); 2576 } 2577 2578 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx) 2579 { 2580 ieee80211_rx_result res = RX_DROP_MONITOR; 2581 2582 #define CALL_RXH(rxh) \ 2583 do { \ 2584 res = rxh(rx); \ 2585 if (res != RX_CONTINUE) \ 2586 goto rxh_next; \ 2587 } while (0); 2588 2589 CALL_RXH(ieee80211_rx_h_passive_scan) 2590 CALL_RXH(ieee80211_rx_h_check) 2591 2592 ieee80211_rx_reorder_ampdu(rx); 2593 2594 ieee80211_rx_handlers(rx); 2595 return; 2596 2597 rxh_next: 2598 ieee80211_rx_handlers_result(rx, res); 2599 2600 #undef CALL_RXH 2601 } 2602 2603 /* 2604 * This function makes calls into the RX path, therefore 2605 * it has to be invoked under RCU read lock. 2606 */ 2607 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid) 2608 { 2609 struct ieee80211_rx_data rx = { 2610 .sta = sta, 2611 .sdata = sta->sdata, 2612 .local = sta->local, 2613 .queue = tid, 2614 }; 2615 struct tid_ampdu_rx *tid_agg_rx; 2616 2617 tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 2618 if (!tid_agg_rx) 2619 return; 2620 2621 spin_lock(&tid_agg_rx->reorder_lock); 2622 ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx); 2623 spin_unlock(&tid_agg_rx->reorder_lock); 2624 2625 ieee80211_rx_handlers(&rx); 2626 } 2627 2628 /* main receive path */ 2629 2630 static int prepare_for_handlers(struct ieee80211_rx_data *rx, 2631 struct ieee80211_hdr *hdr) 2632 { 2633 struct ieee80211_sub_if_data *sdata = rx->sdata; 2634 struct sk_buff *skb = rx->skb; 2635 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2636 u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 2637 int multicast = is_multicast_ether_addr(hdr->addr1); 2638 2639 switch (sdata->vif.type) { 2640 case NL80211_IFTYPE_STATION: 2641 if (!bssid && !sdata->u.mgd.use_4addr) 2642 return 0; 2643 if (!multicast && 2644 compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { 2645 if (!(sdata->dev->flags & IFF_PROMISC) || 2646 sdata->u.mgd.use_4addr) 2647 return 0; 2648 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2649 } 2650 break; 2651 case NL80211_IFTYPE_ADHOC: 2652 if (!bssid) 2653 return 0; 2654 if (ieee80211_is_beacon(hdr->frame_control)) { 2655 return 1; 2656 } 2657 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2658 if (!(status->rx_flags & IEEE80211_RX_IN_SCAN)) 2659 return 0; 2660 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2661 } else if (!multicast && 2662 compare_ether_addr(sdata->vif.addr, 2663 hdr->addr1) != 0) { 2664 if (!(sdata->dev->flags & IFF_PROMISC)) 2665 return 0; 2666 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2667 } else if (!rx->sta) { 2668 int rate_idx; 2669 if (status->flag & RX_FLAG_HT) 2670 rate_idx = 0; /* TODO: HT rates */ 2671 else 2672 rate_idx = status->rate_idx; 2673 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, 2674 hdr->addr2, BIT(rate_idx), GFP_ATOMIC); 2675 } 2676 break; 2677 case NL80211_IFTYPE_MESH_POINT: 2678 if (!multicast && 2679 compare_ether_addr(sdata->vif.addr, 2680 hdr->addr1) != 0) { 2681 if (!(sdata->dev->flags & IFF_PROMISC)) 2682 return 0; 2683 2684 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2685 } 2686 break; 2687 case NL80211_IFTYPE_AP_VLAN: 2688 case NL80211_IFTYPE_AP: 2689 if (!bssid) { 2690 if (compare_ether_addr(sdata->vif.addr, 2691 hdr->addr1)) 2692 return 0; 2693 } else if (!ieee80211_bssid_match(bssid, 2694 sdata->vif.addr)) { 2695 if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) && 2696 !ieee80211_is_beacon(hdr->frame_control)) 2697 return 0; 2698 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2699 } 2700 break; 2701 case NL80211_IFTYPE_WDS: 2702 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2703 return 0; 2704 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2705 return 0; 2706 break; 2707 default: 2708 /* should never get here */ 2709 WARN_ON(1); 2710 break; 2711 } 2712 2713 return 1; 2714 } 2715 2716 /* 2717 * This function returns whether or not the SKB 2718 * was destined for RX processing or not, which, 2719 * if consume is true, is equivalent to whether 2720 * or not the skb was consumed. 2721 */ 2722 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx, 2723 struct sk_buff *skb, bool consume) 2724 { 2725 struct ieee80211_local *local = rx->local; 2726 struct ieee80211_sub_if_data *sdata = rx->sdata; 2727 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2728 struct ieee80211_hdr *hdr = (void *)skb->data; 2729 int prepares; 2730 2731 rx->skb = skb; 2732 status->rx_flags |= IEEE80211_RX_RA_MATCH; 2733 prepares = prepare_for_handlers(rx, hdr); 2734 2735 if (!prepares) 2736 return false; 2737 2738 if (status->flag & RX_FLAG_MMIC_ERROR) { 2739 if (status->rx_flags & IEEE80211_RX_RA_MATCH) 2740 ieee80211_rx_michael_mic_report(hdr, rx); 2741 return false; 2742 } 2743 2744 if (!consume) { 2745 skb = skb_copy(skb, GFP_ATOMIC); 2746 if (!skb) { 2747 if (net_ratelimit()) 2748 wiphy_debug(local->hw.wiphy, 2749 "failed to copy skb for %s\n", 2750 sdata->name); 2751 return true; 2752 } 2753 2754 rx->skb = skb; 2755 } 2756 2757 ieee80211_invoke_rx_handlers(rx); 2758 return true; 2759 } 2760 2761 /* 2762 * This is the actual Rx frames handler. as it blongs to Rx path it must 2763 * be called with rcu_read_lock protection. 2764 */ 2765 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2766 struct sk_buff *skb) 2767 { 2768 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2769 struct ieee80211_local *local = hw_to_local(hw); 2770 struct ieee80211_sub_if_data *sdata; 2771 struct ieee80211_hdr *hdr; 2772 __le16 fc; 2773 struct ieee80211_rx_data rx; 2774 struct ieee80211_sub_if_data *prev; 2775 struct sta_info *sta, *tmp, *prev_sta; 2776 int err = 0; 2777 2778 fc = ((struct ieee80211_hdr *)skb->data)->frame_control; 2779 memset(&rx, 0, sizeof(rx)); 2780 rx.skb = skb; 2781 rx.local = local; 2782 2783 if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) 2784 local->dot11ReceivedFragmentCount++; 2785 2786 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2787 test_bit(SCAN_SW_SCANNING, &local->scanning))) 2788 status->rx_flags |= IEEE80211_RX_IN_SCAN; 2789 2790 if (ieee80211_is_mgmt(fc)) 2791 err = skb_linearize(skb); 2792 else 2793 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); 2794 2795 if (err) { 2796 dev_kfree_skb(skb); 2797 return; 2798 } 2799 2800 hdr = (struct ieee80211_hdr *)skb->data; 2801 ieee80211_parse_qos(&rx); 2802 ieee80211_verify_alignment(&rx); 2803 2804 if (ieee80211_is_data(fc)) { 2805 prev_sta = NULL; 2806 2807 for_each_sta_info(local, hdr->addr2, sta, tmp) { 2808 if (!prev_sta) { 2809 prev_sta = sta; 2810 continue; 2811 } 2812 2813 rx.sta = prev_sta; 2814 rx.sdata = prev_sta->sdata; 2815 ieee80211_prepare_and_rx_handle(&rx, skb, false); 2816 2817 prev_sta = sta; 2818 } 2819 2820 if (prev_sta) { 2821 rx.sta = prev_sta; 2822 rx.sdata = prev_sta->sdata; 2823 2824 if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) 2825 return; 2826 goto out; 2827 } 2828 } 2829 2830 prev = NULL; 2831 2832 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2833 if (!ieee80211_sdata_running(sdata)) 2834 continue; 2835 2836 if (sdata->vif.type == NL80211_IFTYPE_MONITOR || 2837 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2838 continue; 2839 2840 /* 2841 * frame is destined for this interface, but if it's 2842 * not also for the previous one we handle that after 2843 * the loop to avoid copying the SKB once too much 2844 */ 2845 2846 if (!prev) { 2847 prev = sdata; 2848 continue; 2849 } 2850 2851 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2852 rx.sdata = prev; 2853 ieee80211_prepare_and_rx_handle(&rx, skb, false); 2854 2855 prev = sdata; 2856 } 2857 2858 if (prev) { 2859 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2860 rx.sdata = prev; 2861 2862 if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) 2863 return; 2864 } 2865 2866 out: 2867 dev_kfree_skb(skb); 2868 } 2869 2870 /* 2871 * This is the receive path handler. It is called by a low level driver when an 2872 * 802.11 MPDU is received from the hardware. 2873 */ 2874 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2875 { 2876 struct ieee80211_local *local = hw_to_local(hw); 2877 struct ieee80211_rate *rate = NULL; 2878 struct ieee80211_supported_band *sband; 2879 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2880 2881 WARN_ON_ONCE(softirq_count() == 0); 2882 2883 if (WARN_ON(status->band < 0 || 2884 status->band >= IEEE80211_NUM_BANDS)) 2885 goto drop; 2886 2887 sband = local->hw.wiphy->bands[status->band]; 2888 if (WARN_ON(!sband)) 2889 goto drop; 2890 2891 /* 2892 * If we're suspending, it is possible although not too likely 2893 * that we'd be receiving frames after having already partially 2894 * quiesced the stack. We can't process such frames then since 2895 * that might, for example, cause stations to be added or other 2896 * driver callbacks be invoked. 2897 */ 2898 if (unlikely(local->quiescing || local->suspended)) 2899 goto drop; 2900 2901 /* 2902 * The same happens when we're not even started, 2903 * but that's worth a warning. 2904 */ 2905 if (WARN_ON(!local->started)) 2906 goto drop; 2907 2908 if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) { 2909 /* 2910 * Validate the rate, unless a PLCP error means that 2911 * we probably can't have a valid rate here anyway. 2912 */ 2913 2914 if (status->flag & RX_FLAG_HT) { 2915 /* 2916 * rate_idx is MCS index, which can be [0-76] 2917 * as documented on: 2918 * 2919 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n 2920 * 2921 * Anything else would be some sort of driver or 2922 * hardware error. The driver should catch hardware 2923 * errors. 2924 */ 2925 if (WARN((status->rate_idx < 0 || 2926 status->rate_idx > 76), 2927 "Rate marked as an HT rate but passed " 2928 "status->rate_idx is not " 2929 "an MCS index [0-76]: %d (0x%02x)\n", 2930 status->rate_idx, 2931 status->rate_idx)) 2932 goto drop; 2933 } else { 2934 if (WARN_ON(status->rate_idx < 0 || 2935 status->rate_idx >= sband->n_bitrates)) 2936 goto drop; 2937 rate = &sband->bitrates[status->rate_idx]; 2938 } 2939 } 2940 2941 status->rx_flags = 0; 2942 2943 /* 2944 * key references and virtual interfaces are protected using RCU 2945 * and this requires that we are in a read-side RCU section during 2946 * receive processing 2947 */ 2948 rcu_read_lock(); 2949 2950 /* 2951 * Frames with failed FCS/PLCP checksum are not returned, 2952 * all other frames are returned without radiotap header 2953 * if it was previously present. 2954 * Also, frames with less than 16 bytes are dropped. 2955 */ 2956 skb = ieee80211_rx_monitor(local, skb, rate); 2957 if (!skb) { 2958 rcu_read_unlock(); 2959 return; 2960 } 2961 2962 ieee80211_tpt_led_trig_rx(local, 2963 ((struct ieee80211_hdr *)skb->data)->frame_control, 2964 skb->len); 2965 __ieee80211_rx_handle_packet(hw, skb); 2966 2967 rcu_read_unlock(); 2968 2969 return; 2970 drop: 2971 kfree_skb(skb); 2972 } 2973 EXPORT_SYMBOL(ieee80211_rx); 2974 2975 /* This is a version of the rx handler that can be called from hard irq 2976 * context. Post the skb on the queue and schedule the tasklet */ 2977 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2978 { 2979 struct ieee80211_local *local = hw_to_local(hw); 2980 2981 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2982 2983 skb->pkt_type = IEEE80211_RX_MSG; 2984 skb_queue_tail(&local->skb_queue, skb); 2985 tasklet_schedule(&local->tasklet); 2986 } 2987 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2988