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 between 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 (skipped && 616 !time_after(jiffies, tid_agg_rx->reorder_time[j] + 617 HT_RX_REORDER_BUF_TIMEOUT)) 618 goto set_release_timer; 619 620 #ifdef CONFIG_MAC80211_HT_DEBUG 621 if (net_ratelimit()) 622 wiphy_debug(hw->wiphy, 623 "release an RX reorder frame due to timeout on earlier frames\n"); 624 #endif 625 ieee80211_release_reorder_frame(hw, tid_agg_rx, j); 626 627 /* 628 * Increment the head seq# also for the skipped slots. 629 */ 630 tid_agg_rx->head_seq_num = 631 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK; 632 skipped = 0; 633 } 634 } else while (tid_agg_rx->reorder_buf[index]) { 635 ieee80211_release_reorder_frame(hw, tid_agg_rx, index); 636 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) % 637 tid_agg_rx->buf_size; 638 } 639 640 if (tid_agg_rx->stored_mpdu_num) { 641 j = index = seq_sub(tid_agg_rx->head_seq_num, 642 tid_agg_rx->ssn) % tid_agg_rx->buf_size; 643 644 for (; j != (index - 1) % tid_agg_rx->buf_size; 645 j = (j + 1) % tid_agg_rx->buf_size) { 646 if (tid_agg_rx->reorder_buf[j]) 647 break; 648 } 649 650 set_release_timer: 651 652 mod_timer(&tid_agg_rx->reorder_timer, 653 tid_agg_rx->reorder_time[j] + 654 HT_RX_REORDER_BUF_TIMEOUT); 655 } else { 656 del_timer(&tid_agg_rx->reorder_timer); 657 } 658 } 659 660 /* 661 * As this function belongs to the RX path it must be under 662 * rcu_read_lock protection. It returns false if the frame 663 * can be processed immediately, true if it was consumed. 664 */ 665 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 666 struct tid_ampdu_rx *tid_agg_rx, 667 struct sk_buff *skb) 668 { 669 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 670 u16 sc = le16_to_cpu(hdr->seq_ctrl); 671 u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 672 u16 head_seq_num, buf_size; 673 int index; 674 bool ret = true; 675 676 spin_lock(&tid_agg_rx->reorder_lock); 677 678 buf_size = tid_agg_rx->buf_size; 679 head_seq_num = tid_agg_rx->head_seq_num; 680 681 /* frame with out of date sequence number */ 682 if (seq_less(mpdu_seq_num, head_seq_num)) { 683 dev_kfree_skb(skb); 684 goto out; 685 } 686 687 /* 688 * If frame the sequence number exceeds our buffering window 689 * size release some previous frames to make room for this one. 690 */ 691 if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) { 692 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size)); 693 /* release stored frames up to new head to stack */ 694 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num); 695 } 696 697 /* Now the new frame is always in the range of the reordering buffer */ 698 699 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size; 700 701 /* check if we already stored this frame */ 702 if (tid_agg_rx->reorder_buf[index]) { 703 dev_kfree_skb(skb); 704 goto out; 705 } 706 707 /* 708 * If the current MPDU is in the right order and nothing else 709 * is stored we can process it directly, no need to buffer it. 710 */ 711 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 712 tid_agg_rx->stored_mpdu_num == 0) { 713 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 714 ret = false; 715 goto out; 716 } 717 718 /* put the frame in the reordering buffer */ 719 tid_agg_rx->reorder_buf[index] = skb; 720 tid_agg_rx->reorder_time[index] = jiffies; 721 tid_agg_rx->stored_mpdu_num++; 722 ieee80211_sta_reorder_release(hw, tid_agg_rx); 723 724 out: 725 spin_unlock(&tid_agg_rx->reorder_lock); 726 return ret; 727 } 728 729 /* 730 * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns 731 * true if the MPDU was buffered, false if it should be processed. 732 */ 733 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx) 734 { 735 struct sk_buff *skb = rx->skb; 736 struct ieee80211_local *local = rx->local; 737 struct ieee80211_hw *hw = &local->hw; 738 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 739 struct sta_info *sta = rx->sta; 740 struct tid_ampdu_rx *tid_agg_rx; 741 u16 sc; 742 int tid; 743 744 if (!ieee80211_is_data_qos(hdr->frame_control)) 745 goto dont_reorder; 746 747 /* 748 * filter the QoS data rx stream according to 749 * STA/TID and check if this STA/TID is on aggregation 750 */ 751 752 if (!sta) 753 goto dont_reorder; 754 755 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 756 757 tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 758 if (!tid_agg_rx) 759 goto dont_reorder; 760 761 /* qos null data frames are excluded */ 762 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 763 goto dont_reorder; 764 765 /* new, potentially un-ordered, ampdu frame - process it */ 766 767 /* reset session timer */ 768 if (tid_agg_rx->timeout) 769 mod_timer(&tid_agg_rx->session_timer, 770 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 771 772 /* if this mpdu is fragmented - terminate rx aggregation session */ 773 sc = le16_to_cpu(hdr->seq_ctrl); 774 if (sc & IEEE80211_SCTL_FRAG) { 775 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 776 skb_queue_tail(&rx->sdata->skb_queue, skb); 777 ieee80211_queue_work(&local->hw, &rx->sdata->work); 778 return; 779 } 780 781 /* 782 * No locking needed -- we will only ever process one 783 * RX packet at a time, and thus own tid_agg_rx. All 784 * other code manipulating it needs to (and does) make 785 * sure that we cannot get to it any more before doing 786 * anything with it. 787 */ 788 if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb)) 789 return; 790 791 dont_reorder: 792 skb_queue_tail(&local->rx_skb_queue, skb); 793 } 794 795 static ieee80211_rx_result debug_noinline 796 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 797 { 798 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 799 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 800 801 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 802 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 803 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 804 rx->sta->last_seq_ctrl[rx->queue] == 805 hdr->seq_ctrl)) { 806 if (status->rx_flags & IEEE80211_RX_RA_MATCH) { 807 rx->local->dot11FrameDuplicateCount++; 808 rx->sta->num_duplicates++; 809 } 810 return RX_DROP_UNUSABLE; 811 } else 812 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 813 } 814 815 if (unlikely(rx->skb->len < 16)) { 816 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 817 return RX_DROP_MONITOR; 818 } 819 820 /* Drop disallowed frame classes based on STA auth/assoc state; 821 * IEEE 802.11, Chap 5.5. 822 * 823 * mac80211 filters only based on association state, i.e. it drops 824 * Class 3 frames from not associated stations. hostapd sends 825 * deauth/disassoc frames when needed. In addition, hostapd is 826 * responsible for filtering on both auth and assoc states. 827 */ 828 829 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 830 return ieee80211_rx_mesh_check(rx); 831 832 if (unlikely((ieee80211_is_data(hdr->frame_control) || 833 ieee80211_is_pspoll(hdr->frame_control)) && 834 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 835 rx->sdata->vif.type != NL80211_IFTYPE_WDS && 836 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) 837 return RX_DROP_MONITOR; 838 839 return RX_CONTINUE; 840 } 841 842 843 static ieee80211_rx_result debug_noinline 844 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 845 { 846 struct sk_buff *skb = rx->skb; 847 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 848 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 849 int keyidx; 850 int hdrlen; 851 ieee80211_rx_result result = RX_DROP_UNUSABLE; 852 struct ieee80211_key *sta_ptk = NULL; 853 int mmie_keyidx = -1; 854 __le16 fc; 855 856 /* 857 * Key selection 101 858 * 859 * There are four types of keys: 860 * - GTK (group keys) 861 * - IGTK (group keys for management frames) 862 * - PTK (pairwise keys) 863 * - STK (station-to-station pairwise keys) 864 * 865 * When selecting a key, we have to distinguish between multicast 866 * (including broadcast) and unicast frames, the latter can only 867 * use PTKs and STKs while the former always use GTKs and IGTKs. 868 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 869 * unicast frames can also use key indices like GTKs. Hence, if we 870 * don't have a PTK/STK we check the key index for a WEP key. 871 * 872 * Note that in a regular BSS, multicast frames are sent by the 873 * AP only, associated stations unicast the frame to the AP first 874 * which then multicasts it on their behalf. 875 * 876 * There is also a slight problem in IBSS mode: GTKs are negotiated 877 * with each station, that is something we don't currently handle. 878 * The spec seems to expect that one negotiates the same key with 879 * every station but there's no such requirement; VLANs could be 880 * possible. 881 */ 882 883 /* 884 * No point in finding a key and decrypting if the frame is neither 885 * addressed to us nor a multicast frame. 886 */ 887 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 888 return RX_CONTINUE; 889 890 /* start without a key */ 891 rx->key = NULL; 892 893 if (rx->sta) 894 sta_ptk = rcu_dereference(rx->sta->ptk); 895 896 fc = hdr->frame_control; 897 898 if (!ieee80211_has_protected(fc)) 899 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 900 901 if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) { 902 rx->key = sta_ptk; 903 if ((status->flag & RX_FLAG_DECRYPTED) && 904 (status->flag & RX_FLAG_IV_STRIPPED)) 905 return RX_CONTINUE; 906 /* Skip decryption if the frame is not protected. */ 907 if (!ieee80211_has_protected(fc)) 908 return RX_CONTINUE; 909 } else if (mmie_keyidx >= 0) { 910 /* Broadcast/multicast robust management frame / BIP */ 911 if ((status->flag & RX_FLAG_DECRYPTED) && 912 (status->flag & RX_FLAG_IV_STRIPPED)) 913 return RX_CONTINUE; 914 915 if (mmie_keyidx < NUM_DEFAULT_KEYS || 916 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 917 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 918 if (rx->sta) 919 rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]); 920 if (!rx->key) 921 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 922 } else if (!ieee80211_has_protected(fc)) { 923 /* 924 * The frame was not protected, so skip decryption. However, we 925 * need to set rx->key if there is a key that could have been 926 * used so that the frame may be dropped if encryption would 927 * have been expected. 928 */ 929 struct ieee80211_key *key = NULL; 930 struct ieee80211_sub_if_data *sdata = rx->sdata; 931 int i; 932 933 if (ieee80211_is_mgmt(fc) && 934 is_multicast_ether_addr(hdr->addr1) && 935 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 936 rx->key = key; 937 else { 938 if (rx->sta) { 939 for (i = 0; i < NUM_DEFAULT_KEYS; i++) { 940 key = rcu_dereference(rx->sta->gtk[i]); 941 if (key) 942 break; 943 } 944 } 945 if (!key) { 946 for (i = 0; i < NUM_DEFAULT_KEYS; i++) { 947 key = rcu_dereference(sdata->keys[i]); 948 if (key) 949 break; 950 } 951 } 952 if (key) 953 rx->key = key; 954 } 955 return RX_CONTINUE; 956 } else { 957 u8 keyid; 958 /* 959 * The device doesn't give us the IV so we won't be 960 * able to look up the key. That's ok though, we 961 * don't need to decrypt the frame, we just won't 962 * be able to keep statistics accurate. 963 * Except for key threshold notifications, should 964 * we somehow allow the driver to tell us which key 965 * the hardware used if this flag is set? 966 */ 967 if ((status->flag & RX_FLAG_DECRYPTED) && 968 (status->flag & RX_FLAG_IV_STRIPPED)) 969 return RX_CONTINUE; 970 971 hdrlen = ieee80211_hdrlen(fc); 972 973 if (rx->skb->len < 8 + hdrlen) 974 return RX_DROP_UNUSABLE; /* TODO: count this? */ 975 976 /* 977 * no need to call ieee80211_wep_get_keyidx, 978 * it verifies a bunch of things we've done already 979 */ 980 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1); 981 keyidx = keyid >> 6; 982 983 /* check per-station GTK first, if multicast packet */ 984 if (is_multicast_ether_addr(hdr->addr1) && rx->sta) 985 rx->key = rcu_dereference(rx->sta->gtk[keyidx]); 986 987 /* if not found, try default key */ 988 if (!rx->key) { 989 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 990 991 /* 992 * RSNA-protected unicast frames should always be 993 * sent with pairwise or station-to-station keys, 994 * but for WEP we allow using a key index as well. 995 */ 996 if (rx->key && 997 rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 && 998 rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 && 999 !is_multicast_ether_addr(hdr->addr1)) 1000 rx->key = NULL; 1001 } 1002 } 1003 1004 if (rx->key) { 1005 rx->key->tx_rx_count++; 1006 /* TODO: add threshold stuff again */ 1007 } else { 1008 return RX_DROP_MONITOR; 1009 } 1010 1011 if (skb_linearize(rx->skb)) 1012 return RX_DROP_UNUSABLE; 1013 /* the hdr variable is invalid now! */ 1014 1015 switch (rx->key->conf.cipher) { 1016 case WLAN_CIPHER_SUITE_WEP40: 1017 case WLAN_CIPHER_SUITE_WEP104: 1018 /* Check for weak IVs if possible */ 1019 if (rx->sta && ieee80211_is_data(fc) && 1020 (!(status->flag & RX_FLAG_IV_STRIPPED) || 1021 !(status->flag & RX_FLAG_DECRYPTED)) && 1022 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 1023 rx->sta->wep_weak_iv_count++; 1024 1025 result = ieee80211_crypto_wep_decrypt(rx); 1026 break; 1027 case WLAN_CIPHER_SUITE_TKIP: 1028 result = ieee80211_crypto_tkip_decrypt(rx); 1029 break; 1030 case WLAN_CIPHER_SUITE_CCMP: 1031 result = ieee80211_crypto_ccmp_decrypt(rx); 1032 break; 1033 case WLAN_CIPHER_SUITE_AES_CMAC: 1034 result = ieee80211_crypto_aes_cmac_decrypt(rx); 1035 break; 1036 default: 1037 /* 1038 * We can reach here only with HW-only algorithms 1039 * but why didn't it decrypt the frame?! 1040 */ 1041 return RX_DROP_UNUSABLE; 1042 } 1043 1044 /* either the frame has been decrypted or will be dropped */ 1045 status->flag |= RX_FLAG_DECRYPTED; 1046 1047 return result; 1048 } 1049 1050 static ieee80211_rx_result debug_noinline 1051 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 1052 { 1053 struct ieee80211_local *local; 1054 struct ieee80211_hdr *hdr; 1055 struct sk_buff *skb; 1056 1057 local = rx->local; 1058 skb = rx->skb; 1059 hdr = (struct ieee80211_hdr *) skb->data; 1060 1061 if (!local->pspolling) 1062 return RX_CONTINUE; 1063 1064 if (!ieee80211_has_fromds(hdr->frame_control)) 1065 /* this is not from AP */ 1066 return RX_CONTINUE; 1067 1068 if (!ieee80211_is_data(hdr->frame_control)) 1069 return RX_CONTINUE; 1070 1071 if (!ieee80211_has_moredata(hdr->frame_control)) { 1072 /* AP has no more frames buffered for us */ 1073 local->pspolling = false; 1074 return RX_CONTINUE; 1075 } 1076 1077 /* more data bit is set, let's request a new frame from the AP */ 1078 ieee80211_send_pspoll(local, rx->sdata); 1079 1080 return RX_CONTINUE; 1081 } 1082 1083 static void ap_sta_ps_start(struct sta_info *sta) 1084 { 1085 struct ieee80211_sub_if_data *sdata = sta->sdata; 1086 struct ieee80211_local *local = sdata->local; 1087 1088 atomic_inc(&sdata->bss->num_sta_ps); 1089 set_sta_flags(sta, WLAN_STA_PS_STA); 1090 if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) 1091 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta); 1092 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1093 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 1094 sdata->name, sta->sta.addr, sta->sta.aid); 1095 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1096 } 1097 1098 static void ap_sta_ps_end(struct sta_info *sta) 1099 { 1100 struct ieee80211_sub_if_data *sdata = sta->sdata; 1101 1102 atomic_dec(&sdata->bss->num_sta_ps); 1103 1104 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1105 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 1106 sdata->name, sta->sta.addr, sta->sta.aid); 1107 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1108 1109 if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) { 1110 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1111 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n", 1112 sdata->name, sta->sta.addr, sta->sta.aid); 1113 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1114 return; 1115 } 1116 1117 ieee80211_sta_ps_deliver_wakeup(sta); 1118 } 1119 1120 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start) 1121 { 1122 struct sta_info *sta_inf = container_of(sta, struct sta_info, sta); 1123 bool in_ps; 1124 1125 WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS)); 1126 1127 /* Don't let the same PS state be set twice */ 1128 in_ps = test_sta_flags(sta_inf, WLAN_STA_PS_STA); 1129 if ((start && in_ps) || (!start && !in_ps)) 1130 return -EINVAL; 1131 1132 if (start) 1133 ap_sta_ps_start(sta_inf); 1134 else 1135 ap_sta_ps_end(sta_inf); 1136 1137 return 0; 1138 } 1139 EXPORT_SYMBOL(ieee80211_sta_ps_transition); 1140 1141 static ieee80211_rx_result debug_noinline 1142 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 1143 { 1144 struct sta_info *sta = rx->sta; 1145 struct sk_buff *skb = rx->skb; 1146 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1147 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1148 1149 if (!sta) 1150 return RX_CONTINUE; 1151 1152 /* 1153 * Update last_rx only for IBSS packets which are for the current 1154 * BSSID to avoid keeping the current IBSS network alive in cases 1155 * where other STAs start using different BSSID. 1156 */ 1157 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 1158 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 1159 NL80211_IFTYPE_ADHOC); 1160 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) { 1161 sta->last_rx = jiffies; 1162 if (ieee80211_is_data(hdr->frame_control)) { 1163 sta->last_rx_rate_idx = status->rate_idx; 1164 sta->last_rx_rate_flag = status->flag; 1165 } 1166 } 1167 } else if (!is_multicast_ether_addr(hdr->addr1)) { 1168 /* 1169 * Mesh beacons will update last_rx when if they are found to 1170 * match the current local configuration when processed. 1171 */ 1172 sta->last_rx = jiffies; 1173 if (ieee80211_is_data(hdr->frame_control)) { 1174 sta->last_rx_rate_idx = status->rate_idx; 1175 sta->last_rx_rate_flag = status->flag; 1176 } 1177 } 1178 1179 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 1180 return RX_CONTINUE; 1181 1182 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 1183 ieee80211_sta_rx_notify(rx->sdata, hdr); 1184 1185 sta->rx_fragments++; 1186 sta->rx_bytes += rx->skb->len; 1187 sta->last_signal = status->signal; 1188 ewma_add(&sta->avg_signal, -status->signal); 1189 1190 /* 1191 * Change STA power saving mode only at the end of a frame 1192 * exchange sequence. 1193 */ 1194 if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) && 1195 !ieee80211_has_morefrags(hdr->frame_control) && 1196 !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) && 1197 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1198 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 1199 if (test_sta_flags(sta, WLAN_STA_PS_STA)) { 1200 /* 1201 * Ignore doze->wake transitions that are 1202 * indicated by non-data frames, the standard 1203 * is unclear here, but for example going to 1204 * PS mode and then scanning would cause a 1205 * doze->wake transition for the probe request, 1206 * and that is clearly undesirable. 1207 */ 1208 if (ieee80211_is_data(hdr->frame_control) && 1209 !ieee80211_has_pm(hdr->frame_control)) 1210 ap_sta_ps_end(sta); 1211 } else { 1212 if (ieee80211_has_pm(hdr->frame_control)) 1213 ap_sta_ps_start(sta); 1214 } 1215 } 1216 1217 /* 1218 * Drop (qos-)data::nullfunc frames silently, since they 1219 * are used only to control station power saving mode. 1220 */ 1221 if (ieee80211_is_nullfunc(hdr->frame_control) || 1222 ieee80211_is_qos_nullfunc(hdr->frame_control)) { 1223 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 1224 1225 /* 1226 * If we receive a 4-addr nullfunc frame from a STA 1227 * that was not moved to a 4-addr STA vlan yet, drop 1228 * the frame to the monitor interface, to make sure 1229 * that hostapd sees it 1230 */ 1231 if (ieee80211_has_a4(hdr->frame_control) && 1232 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 1233 (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1234 !rx->sdata->u.vlan.sta))) 1235 return RX_DROP_MONITOR; 1236 /* 1237 * Update counter and free packet here to avoid 1238 * counting this as a dropped packed. 1239 */ 1240 sta->rx_packets++; 1241 dev_kfree_skb(rx->skb); 1242 return RX_QUEUED; 1243 } 1244 1245 return RX_CONTINUE; 1246 } /* ieee80211_rx_h_sta_process */ 1247 1248 static inline struct ieee80211_fragment_entry * 1249 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 1250 unsigned int frag, unsigned int seq, int rx_queue, 1251 struct sk_buff **skb) 1252 { 1253 struct ieee80211_fragment_entry *entry; 1254 int idx; 1255 1256 idx = sdata->fragment_next; 1257 entry = &sdata->fragments[sdata->fragment_next++]; 1258 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 1259 sdata->fragment_next = 0; 1260 1261 if (!skb_queue_empty(&entry->skb_list)) { 1262 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1263 struct ieee80211_hdr *hdr = 1264 (struct ieee80211_hdr *) entry->skb_list.next->data; 1265 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 1266 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 1267 "addr1=%pM addr2=%pM\n", 1268 sdata->name, idx, 1269 jiffies - entry->first_frag_time, entry->seq, 1270 entry->last_frag, hdr->addr1, hdr->addr2); 1271 #endif 1272 __skb_queue_purge(&entry->skb_list); 1273 } 1274 1275 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 1276 *skb = NULL; 1277 entry->first_frag_time = jiffies; 1278 entry->seq = seq; 1279 entry->rx_queue = rx_queue; 1280 entry->last_frag = frag; 1281 entry->ccmp = 0; 1282 entry->extra_len = 0; 1283 1284 return entry; 1285 } 1286 1287 static inline struct ieee80211_fragment_entry * 1288 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 1289 unsigned int frag, unsigned int seq, 1290 int rx_queue, struct ieee80211_hdr *hdr) 1291 { 1292 struct ieee80211_fragment_entry *entry; 1293 int i, idx; 1294 1295 idx = sdata->fragment_next; 1296 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 1297 struct ieee80211_hdr *f_hdr; 1298 1299 idx--; 1300 if (idx < 0) 1301 idx = IEEE80211_FRAGMENT_MAX - 1; 1302 1303 entry = &sdata->fragments[idx]; 1304 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 1305 entry->rx_queue != rx_queue || 1306 entry->last_frag + 1 != frag) 1307 continue; 1308 1309 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 1310 1311 /* 1312 * Check ftype and addresses are equal, else check next fragment 1313 */ 1314 if (((hdr->frame_control ^ f_hdr->frame_control) & 1315 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 1316 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 1317 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 1318 continue; 1319 1320 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 1321 __skb_queue_purge(&entry->skb_list); 1322 continue; 1323 } 1324 return entry; 1325 } 1326 1327 return NULL; 1328 } 1329 1330 static ieee80211_rx_result debug_noinline 1331 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 1332 { 1333 struct ieee80211_hdr *hdr; 1334 u16 sc; 1335 __le16 fc; 1336 unsigned int frag, seq; 1337 struct ieee80211_fragment_entry *entry; 1338 struct sk_buff *skb; 1339 struct ieee80211_rx_status *status; 1340 1341 hdr = (struct ieee80211_hdr *)rx->skb->data; 1342 fc = hdr->frame_control; 1343 sc = le16_to_cpu(hdr->seq_ctrl); 1344 frag = sc & IEEE80211_SCTL_FRAG; 1345 1346 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1347 (rx->skb)->len < 24 || 1348 is_multicast_ether_addr(hdr->addr1))) { 1349 /* not fragmented */ 1350 goto out; 1351 } 1352 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1353 1354 if (skb_linearize(rx->skb)) 1355 return RX_DROP_UNUSABLE; 1356 1357 /* 1358 * skb_linearize() might change the skb->data and 1359 * previously cached variables (in this case, hdr) need to 1360 * be refreshed with the new data. 1361 */ 1362 hdr = (struct ieee80211_hdr *)rx->skb->data; 1363 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1364 1365 if (frag == 0) { 1366 /* This is the first fragment of a new frame. */ 1367 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1368 rx->queue, &(rx->skb)); 1369 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP && 1370 ieee80211_has_protected(fc)) { 1371 int queue = ieee80211_is_mgmt(fc) ? 1372 NUM_RX_DATA_QUEUES : rx->queue; 1373 /* Store CCMP PN so that we can verify that the next 1374 * fragment has a sequential PN value. */ 1375 entry->ccmp = 1; 1376 memcpy(entry->last_pn, 1377 rx->key->u.ccmp.rx_pn[queue], 1378 CCMP_PN_LEN); 1379 } 1380 return RX_QUEUED; 1381 } 1382 1383 /* This is a fragment for a frame that should already be pending in 1384 * fragment cache. Add this fragment to the end of the pending entry. 1385 */ 1386 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1387 if (!entry) { 1388 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1389 return RX_DROP_MONITOR; 1390 } 1391 1392 /* Verify that MPDUs within one MSDU have sequential PN values. 1393 * (IEEE 802.11i, 8.3.3.4.5) */ 1394 if (entry->ccmp) { 1395 int i; 1396 u8 pn[CCMP_PN_LEN], *rpn; 1397 int queue; 1398 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP) 1399 return RX_DROP_UNUSABLE; 1400 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1401 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1402 pn[i]++; 1403 if (pn[i]) 1404 break; 1405 } 1406 queue = ieee80211_is_mgmt(fc) ? 1407 NUM_RX_DATA_QUEUES : rx->queue; 1408 rpn = rx->key->u.ccmp.rx_pn[queue]; 1409 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1410 return RX_DROP_UNUSABLE; 1411 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1412 } 1413 1414 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1415 __skb_queue_tail(&entry->skb_list, rx->skb); 1416 entry->last_frag = frag; 1417 entry->extra_len += rx->skb->len; 1418 if (ieee80211_has_morefrags(fc)) { 1419 rx->skb = NULL; 1420 return RX_QUEUED; 1421 } 1422 1423 rx->skb = __skb_dequeue(&entry->skb_list); 1424 if (skb_tailroom(rx->skb) < entry->extra_len) { 1425 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1426 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1427 GFP_ATOMIC))) { 1428 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1429 __skb_queue_purge(&entry->skb_list); 1430 return RX_DROP_UNUSABLE; 1431 } 1432 } 1433 while ((skb = __skb_dequeue(&entry->skb_list))) { 1434 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1435 dev_kfree_skb(skb); 1436 } 1437 1438 /* Complete frame has been reassembled - process it now */ 1439 status = IEEE80211_SKB_RXCB(rx->skb); 1440 status->rx_flags |= IEEE80211_RX_FRAGMENTED; 1441 1442 out: 1443 if (rx->sta) 1444 rx->sta->rx_packets++; 1445 if (is_multicast_ether_addr(hdr->addr1)) 1446 rx->local->dot11MulticastReceivedFrameCount++; 1447 else 1448 ieee80211_led_rx(rx->local); 1449 return RX_CONTINUE; 1450 } 1451 1452 static ieee80211_rx_result debug_noinline 1453 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1454 { 1455 struct ieee80211_sub_if_data *sdata = rx->sdata; 1456 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1457 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1458 1459 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1460 !(status->rx_flags & IEEE80211_RX_RA_MATCH))) 1461 return RX_CONTINUE; 1462 1463 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1464 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1465 return RX_DROP_UNUSABLE; 1466 1467 if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER)) 1468 ieee80211_sta_ps_deliver_poll_response(rx->sta); 1469 else 1470 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1471 1472 /* Free PS Poll skb here instead of returning RX_DROP that would 1473 * count as an dropped frame. */ 1474 dev_kfree_skb(rx->skb); 1475 1476 return RX_QUEUED; 1477 } 1478 1479 static ieee80211_rx_result debug_noinline 1480 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1481 { 1482 u8 *data = rx->skb->data; 1483 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1484 1485 if (!ieee80211_is_data_qos(hdr->frame_control)) 1486 return RX_CONTINUE; 1487 1488 /* remove the qos control field, update frame type and meta-data */ 1489 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1490 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1491 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1492 /* change frame type to non QOS */ 1493 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1494 1495 return RX_CONTINUE; 1496 } 1497 1498 static int 1499 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1500 { 1501 if (unlikely(!rx->sta || 1502 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1503 return -EACCES; 1504 1505 return 0; 1506 } 1507 1508 static int 1509 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1510 { 1511 struct sk_buff *skb = rx->skb; 1512 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1513 1514 /* 1515 * Pass through unencrypted frames if the hardware has 1516 * decrypted them already. 1517 */ 1518 if (status->flag & RX_FLAG_DECRYPTED) 1519 return 0; 1520 1521 /* Drop unencrypted frames if key is set. */ 1522 if (unlikely(!ieee80211_has_protected(fc) && 1523 !ieee80211_is_nullfunc(fc) && 1524 ieee80211_is_data(fc) && 1525 (rx->key || rx->sdata->drop_unencrypted))) 1526 return -EACCES; 1527 1528 return 0; 1529 } 1530 1531 static int 1532 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) 1533 { 1534 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1535 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1536 __le16 fc = hdr->frame_control; 1537 1538 /* 1539 * Pass through unencrypted frames if the hardware has 1540 * decrypted them already. 1541 */ 1542 if (status->flag & RX_FLAG_DECRYPTED) 1543 return 0; 1544 1545 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1546 if (unlikely(!ieee80211_has_protected(fc) && 1547 ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1548 rx->key)) { 1549 if (ieee80211_is_deauth(fc)) 1550 cfg80211_send_unprot_deauth(rx->sdata->dev, 1551 rx->skb->data, 1552 rx->skb->len); 1553 else if (ieee80211_is_disassoc(fc)) 1554 cfg80211_send_unprot_disassoc(rx->sdata->dev, 1555 rx->skb->data, 1556 rx->skb->len); 1557 return -EACCES; 1558 } 1559 /* BIP does not use Protected field, so need to check MMIE */ 1560 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) && 1561 ieee80211_get_mmie_keyidx(rx->skb) < 0)) { 1562 if (ieee80211_is_deauth(fc)) 1563 cfg80211_send_unprot_deauth(rx->sdata->dev, 1564 rx->skb->data, 1565 rx->skb->len); 1566 else if (ieee80211_is_disassoc(fc)) 1567 cfg80211_send_unprot_disassoc(rx->sdata->dev, 1568 rx->skb->data, 1569 rx->skb->len); 1570 return -EACCES; 1571 } 1572 /* 1573 * When using MFP, Action frames are not allowed prior to 1574 * having configured keys. 1575 */ 1576 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1577 ieee80211_is_robust_mgmt_frame( 1578 (struct ieee80211_hdr *) rx->skb->data))) 1579 return -EACCES; 1580 } 1581 1582 return 0; 1583 } 1584 1585 static int 1586 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1587 { 1588 struct ieee80211_sub_if_data *sdata = rx->sdata; 1589 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1590 bool check_port_control = false; 1591 struct ethhdr *ehdr; 1592 int ret; 1593 1594 if (ieee80211_has_a4(hdr->frame_control) && 1595 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta) 1596 return -1; 1597 1598 if (sdata->vif.type == NL80211_IFTYPE_STATION && 1599 !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) { 1600 1601 if (!sdata->u.mgd.use_4addr) 1602 return -1; 1603 else 1604 check_port_control = true; 1605 } 1606 1607 if (is_multicast_ether_addr(hdr->addr1) && 1608 sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) 1609 return -1; 1610 1611 ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type); 1612 if (ret < 0 || !check_port_control) 1613 return ret; 1614 1615 ehdr = (struct ethhdr *) rx->skb->data; 1616 if (ehdr->h_proto != rx->sdata->control_port_protocol) 1617 return -1; 1618 1619 return 0; 1620 } 1621 1622 /* 1623 * requires that rx->skb is a frame with ethernet header 1624 */ 1625 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1626 { 1627 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1628 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1629 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1630 1631 /* 1632 * Allow EAPOL frames to us/the PAE group address regardless 1633 * of whether the frame was encrypted or not. 1634 */ 1635 if (ehdr->h_proto == rx->sdata->control_port_protocol && 1636 (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 || 1637 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1638 return true; 1639 1640 if (ieee80211_802_1x_port_control(rx) || 1641 ieee80211_drop_unencrypted(rx, fc)) 1642 return false; 1643 1644 return true; 1645 } 1646 1647 /* 1648 * requires that rx->skb is a frame with ethernet header 1649 */ 1650 static void 1651 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1652 { 1653 struct ieee80211_sub_if_data *sdata = rx->sdata; 1654 struct net_device *dev = sdata->dev; 1655 struct sk_buff *skb, *xmit_skb; 1656 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1657 struct sta_info *dsta; 1658 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1659 1660 skb = rx->skb; 1661 xmit_skb = NULL; 1662 1663 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1664 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1665 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1666 (status->rx_flags & IEEE80211_RX_RA_MATCH) && 1667 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { 1668 if (is_multicast_ether_addr(ehdr->h_dest)) { 1669 /* 1670 * send multicast frames both to higher layers in 1671 * local net stack and back to the wireless medium 1672 */ 1673 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1674 if (!xmit_skb && net_ratelimit()) 1675 printk(KERN_DEBUG "%s: failed to clone " 1676 "multicast frame\n", dev->name); 1677 } else { 1678 dsta = sta_info_get(sdata, skb->data); 1679 if (dsta) { 1680 /* 1681 * The destination station is associated to 1682 * this AP (in this VLAN), so send the frame 1683 * directly to it and do not pass it to local 1684 * net stack. 1685 */ 1686 xmit_skb = skb; 1687 skb = NULL; 1688 } 1689 } 1690 } 1691 1692 if (skb) { 1693 int align __maybe_unused; 1694 1695 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1696 /* 1697 * 'align' will only take the values 0 or 2 here 1698 * since all frames are required to be aligned 1699 * to 2-byte boundaries when being passed to 1700 * mac80211. That also explains the __skb_push() 1701 * below. 1702 */ 1703 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1704 if (align) { 1705 if (WARN_ON(skb_headroom(skb) < 3)) { 1706 dev_kfree_skb(skb); 1707 skb = NULL; 1708 } else { 1709 u8 *data = skb->data; 1710 size_t len = skb_headlen(skb); 1711 skb->data -= align; 1712 memmove(skb->data, data, len); 1713 skb_set_tail_pointer(skb, len); 1714 } 1715 } 1716 #endif 1717 1718 if (skb) { 1719 /* deliver to local stack */ 1720 skb->protocol = eth_type_trans(skb, dev); 1721 memset(skb->cb, 0, sizeof(skb->cb)); 1722 netif_receive_skb(skb); 1723 } 1724 } 1725 1726 if (xmit_skb) { 1727 /* send to wireless media */ 1728 xmit_skb->protocol = htons(ETH_P_802_3); 1729 skb_reset_network_header(xmit_skb); 1730 skb_reset_mac_header(xmit_skb); 1731 dev_queue_xmit(xmit_skb); 1732 } 1733 } 1734 1735 static ieee80211_rx_result debug_noinline 1736 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1737 { 1738 struct net_device *dev = rx->sdata->dev; 1739 struct sk_buff *skb = rx->skb; 1740 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1741 __le16 fc = hdr->frame_control; 1742 struct sk_buff_head frame_list; 1743 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 1744 1745 if (unlikely(!ieee80211_is_data(fc))) 1746 return RX_CONTINUE; 1747 1748 if (unlikely(!ieee80211_is_data_present(fc))) 1749 return RX_DROP_MONITOR; 1750 1751 if (!(status->rx_flags & IEEE80211_RX_AMSDU)) 1752 return RX_CONTINUE; 1753 1754 if (ieee80211_has_a4(hdr->frame_control) && 1755 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1756 !rx->sdata->u.vlan.sta) 1757 return RX_DROP_UNUSABLE; 1758 1759 if (is_multicast_ether_addr(hdr->addr1) && 1760 ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && 1761 rx->sdata->u.vlan.sta) || 1762 (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 1763 rx->sdata->u.mgd.use_4addr))) 1764 return RX_DROP_UNUSABLE; 1765 1766 skb->dev = dev; 1767 __skb_queue_head_init(&frame_list); 1768 1769 if (skb_linearize(skb)) 1770 return RX_DROP_UNUSABLE; 1771 1772 ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr, 1773 rx->sdata->vif.type, 1774 rx->local->hw.extra_tx_headroom); 1775 1776 while (!skb_queue_empty(&frame_list)) { 1777 rx->skb = __skb_dequeue(&frame_list); 1778 1779 if (!ieee80211_frame_allowed(rx, fc)) { 1780 dev_kfree_skb(rx->skb); 1781 continue; 1782 } 1783 dev->stats.rx_packets++; 1784 dev->stats.rx_bytes += rx->skb->len; 1785 1786 ieee80211_deliver_skb(rx); 1787 } 1788 1789 return RX_QUEUED; 1790 } 1791 1792 #ifdef CONFIG_MAC80211_MESH 1793 static ieee80211_rx_result 1794 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1795 { 1796 struct ieee80211_hdr *hdr; 1797 struct ieee80211s_hdr *mesh_hdr; 1798 unsigned int hdrlen; 1799 struct sk_buff *skb = rx->skb, *fwd_skb; 1800 struct ieee80211_local *local = rx->local; 1801 struct ieee80211_sub_if_data *sdata = rx->sdata; 1802 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1803 1804 hdr = (struct ieee80211_hdr *) skb->data; 1805 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1806 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1807 1808 if (!ieee80211_is_data(hdr->frame_control)) 1809 return RX_CONTINUE; 1810 1811 if (!mesh_hdr->ttl) 1812 /* illegal frame */ 1813 return RX_DROP_MONITOR; 1814 1815 if (mesh_hdr->flags & MESH_FLAGS_AE) { 1816 struct mesh_path *mppath; 1817 char *proxied_addr; 1818 char *mpp_addr; 1819 1820 if (is_multicast_ether_addr(hdr->addr1)) { 1821 mpp_addr = hdr->addr3; 1822 proxied_addr = mesh_hdr->eaddr1; 1823 } else { 1824 mpp_addr = hdr->addr4; 1825 proxied_addr = mesh_hdr->eaddr2; 1826 } 1827 1828 rcu_read_lock(); 1829 mppath = mpp_path_lookup(proxied_addr, sdata); 1830 if (!mppath) { 1831 mpp_path_add(proxied_addr, mpp_addr, sdata); 1832 } else { 1833 spin_lock_bh(&mppath->state_lock); 1834 if (compare_ether_addr(mppath->mpp, mpp_addr) != 0) 1835 memcpy(mppath->mpp, mpp_addr, ETH_ALEN); 1836 spin_unlock_bh(&mppath->state_lock); 1837 } 1838 rcu_read_unlock(); 1839 } 1840 1841 /* Frame has reached destination. Don't forward */ 1842 if (!is_multicast_ether_addr(hdr->addr1) && 1843 compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0) 1844 return RX_CONTINUE; 1845 1846 mesh_hdr->ttl--; 1847 1848 if (status->rx_flags & IEEE80211_RX_RA_MATCH) { 1849 if (!mesh_hdr->ttl) 1850 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1851 dropped_frames_ttl); 1852 else { 1853 struct ieee80211_hdr *fwd_hdr; 1854 struct ieee80211_tx_info *info; 1855 1856 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1857 1858 if (!fwd_skb && net_ratelimit()) 1859 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1860 sdata->name); 1861 if (!fwd_skb) 1862 goto out; 1863 1864 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1865 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN); 1866 info = IEEE80211_SKB_CB(fwd_skb); 1867 memset(info, 0, sizeof(*info)); 1868 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1869 info->control.vif = &rx->sdata->vif; 1870 skb_set_queue_mapping(skb, 1871 ieee80211_select_queue(rx->sdata, fwd_skb)); 1872 ieee80211_set_qos_hdr(local, skb); 1873 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1874 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1875 fwded_mcast); 1876 else { 1877 int err; 1878 /* 1879 * Save TA to addr1 to send TA a path error if a 1880 * suitable next hop is not found 1881 */ 1882 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1883 ETH_ALEN); 1884 err = mesh_nexthop_lookup(fwd_skb, sdata); 1885 /* Failed to immediately resolve next hop: 1886 * fwded frame was dropped or will be added 1887 * later to the pending skb queue. */ 1888 if (err) 1889 return RX_DROP_MONITOR; 1890 1891 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1892 fwded_unicast); 1893 } 1894 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1895 fwded_frames); 1896 ieee80211_add_pending_skb(local, fwd_skb); 1897 } 1898 } 1899 1900 out: 1901 if (is_multicast_ether_addr(hdr->addr1) || 1902 sdata->dev->flags & IFF_PROMISC) 1903 return RX_CONTINUE; 1904 else 1905 return RX_DROP_MONITOR; 1906 } 1907 #endif 1908 1909 static ieee80211_rx_result debug_noinline 1910 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1911 { 1912 struct ieee80211_sub_if_data *sdata = rx->sdata; 1913 struct ieee80211_local *local = rx->local; 1914 struct net_device *dev = sdata->dev; 1915 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1916 __le16 fc = hdr->frame_control; 1917 int err; 1918 1919 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1920 return RX_CONTINUE; 1921 1922 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1923 return RX_DROP_MONITOR; 1924 1925 /* 1926 * Allow the cooked monitor interface of an AP to see 4-addr frames so 1927 * that a 4-addr station can be detected and moved into a separate VLAN 1928 */ 1929 if (ieee80211_has_a4(hdr->frame_control) && 1930 sdata->vif.type == NL80211_IFTYPE_AP) 1931 return RX_DROP_MONITOR; 1932 1933 err = __ieee80211_data_to_8023(rx); 1934 if (unlikely(err)) 1935 return RX_DROP_UNUSABLE; 1936 1937 if (!ieee80211_frame_allowed(rx, fc)) 1938 return RX_DROP_MONITOR; 1939 1940 rx->skb->dev = dev; 1941 1942 dev->stats.rx_packets++; 1943 dev->stats.rx_bytes += rx->skb->len; 1944 1945 if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 && 1946 !is_multicast_ether_addr( 1947 ((struct ethhdr *)rx->skb->data)->h_dest) && 1948 (!local->scanning && 1949 !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) { 1950 mod_timer(&local->dynamic_ps_timer, jiffies + 1951 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1952 } 1953 1954 ieee80211_deliver_skb(rx); 1955 1956 return RX_QUEUED; 1957 } 1958 1959 static ieee80211_rx_result debug_noinline 1960 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx) 1961 { 1962 struct ieee80211_local *local = rx->local; 1963 struct ieee80211_hw *hw = &local->hw; 1964 struct sk_buff *skb = rx->skb; 1965 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1966 struct tid_ampdu_rx *tid_agg_rx; 1967 u16 start_seq_num; 1968 u16 tid; 1969 1970 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1971 return RX_CONTINUE; 1972 1973 if (ieee80211_is_back_req(bar->frame_control)) { 1974 struct { 1975 __le16 control, start_seq_num; 1976 } __packed bar_data; 1977 1978 if (!rx->sta) 1979 return RX_DROP_MONITOR; 1980 1981 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control), 1982 &bar_data, sizeof(bar_data))) 1983 return RX_DROP_MONITOR; 1984 1985 tid = le16_to_cpu(bar_data.control) >> 12; 1986 1987 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]); 1988 if (!tid_agg_rx) 1989 return RX_DROP_MONITOR; 1990 1991 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4; 1992 1993 /* reset session timer */ 1994 if (tid_agg_rx->timeout) 1995 mod_timer(&tid_agg_rx->session_timer, 1996 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1997 1998 spin_lock(&tid_agg_rx->reorder_lock); 1999 /* release stored frames up to start of BAR */ 2000 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num); 2001 spin_unlock(&tid_agg_rx->reorder_lock); 2002 2003 kfree_skb(skb); 2004 return RX_QUEUED; 2005 } 2006 2007 /* 2008 * After this point, we only want management frames, 2009 * so we can drop all remaining control frames to 2010 * cooked monitor interfaces. 2011 */ 2012 return RX_DROP_MONITOR; 2013 } 2014 2015 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 2016 struct ieee80211_mgmt *mgmt, 2017 size_t len) 2018 { 2019 struct ieee80211_local *local = sdata->local; 2020 struct sk_buff *skb; 2021 struct ieee80211_mgmt *resp; 2022 2023 if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) { 2024 /* Not to own unicast address */ 2025 return; 2026 } 2027 2028 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 2029 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 2030 /* Not from the current AP or not associated yet. */ 2031 return; 2032 } 2033 2034 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 2035 /* Too short SA Query request frame */ 2036 return; 2037 } 2038 2039 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 2040 if (skb == NULL) 2041 return; 2042 2043 skb_reserve(skb, local->hw.extra_tx_headroom); 2044 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 2045 memset(resp, 0, 24); 2046 memcpy(resp->da, mgmt->sa, ETH_ALEN); 2047 memcpy(resp->sa, sdata->vif.addr, ETH_ALEN); 2048 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 2049 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2050 IEEE80211_STYPE_ACTION); 2051 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 2052 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 2053 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 2054 memcpy(resp->u.action.u.sa_query.trans_id, 2055 mgmt->u.action.u.sa_query.trans_id, 2056 WLAN_SA_QUERY_TR_ID_LEN); 2057 2058 ieee80211_tx_skb(sdata, skb); 2059 } 2060 2061 static ieee80211_rx_result debug_noinline 2062 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx) 2063 { 2064 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2065 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2066 2067 /* 2068 * From here on, look only at management frames. 2069 * Data and control frames are already handled, 2070 * and unknown (reserved) frames are useless. 2071 */ 2072 if (rx->skb->len < 24) 2073 return RX_DROP_MONITOR; 2074 2075 if (!ieee80211_is_mgmt(mgmt->frame_control)) 2076 return RX_DROP_MONITOR; 2077 2078 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 2079 return RX_DROP_MONITOR; 2080 2081 if (ieee80211_drop_unencrypted_mgmt(rx)) 2082 return RX_DROP_UNUSABLE; 2083 2084 return RX_CONTINUE; 2085 } 2086 2087 static ieee80211_rx_result debug_noinline 2088 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 2089 { 2090 struct ieee80211_local *local = rx->local; 2091 struct ieee80211_sub_if_data *sdata = rx->sdata; 2092 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2093 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2094 int len = rx->skb->len; 2095 2096 if (!ieee80211_is_action(mgmt->frame_control)) 2097 return RX_CONTINUE; 2098 2099 /* drop too small frames */ 2100 if (len < IEEE80211_MIN_ACTION_SIZE) 2101 return RX_DROP_UNUSABLE; 2102 2103 if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) 2104 return RX_DROP_UNUSABLE; 2105 2106 if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) 2107 return RX_DROP_UNUSABLE; 2108 2109 switch (mgmt->u.action.category) { 2110 case WLAN_CATEGORY_BACK: 2111 /* 2112 * The aggregation code is not prepared to handle 2113 * anything but STA/AP due to the BSSID handling; 2114 * IBSS could work in the code but isn't supported 2115 * by drivers or the standard. 2116 */ 2117 if (sdata->vif.type != NL80211_IFTYPE_STATION && 2118 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 2119 sdata->vif.type != NL80211_IFTYPE_AP) 2120 break; 2121 2122 /* verify action_code is present */ 2123 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 2124 break; 2125 2126 switch (mgmt->u.action.u.addba_req.action_code) { 2127 case WLAN_ACTION_ADDBA_REQ: 2128 if (len < (IEEE80211_MIN_ACTION_SIZE + 2129 sizeof(mgmt->u.action.u.addba_req))) 2130 goto invalid; 2131 break; 2132 case WLAN_ACTION_ADDBA_RESP: 2133 if (len < (IEEE80211_MIN_ACTION_SIZE + 2134 sizeof(mgmt->u.action.u.addba_resp))) 2135 goto invalid; 2136 break; 2137 case WLAN_ACTION_DELBA: 2138 if (len < (IEEE80211_MIN_ACTION_SIZE + 2139 sizeof(mgmt->u.action.u.delba))) 2140 goto invalid; 2141 break; 2142 default: 2143 goto invalid; 2144 } 2145 2146 goto queue; 2147 case WLAN_CATEGORY_SPECTRUM_MGMT: 2148 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 2149 break; 2150 2151 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2152 break; 2153 2154 /* verify action_code is present */ 2155 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 2156 break; 2157 2158 switch (mgmt->u.action.u.measurement.action_code) { 2159 case WLAN_ACTION_SPCT_MSR_REQ: 2160 if (len < (IEEE80211_MIN_ACTION_SIZE + 2161 sizeof(mgmt->u.action.u.measurement))) 2162 break; 2163 ieee80211_process_measurement_req(sdata, mgmt, len); 2164 goto handled; 2165 case WLAN_ACTION_SPCT_CHL_SWITCH: 2166 if (len < (IEEE80211_MIN_ACTION_SIZE + 2167 sizeof(mgmt->u.action.u.chan_switch))) 2168 break; 2169 2170 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2171 break; 2172 2173 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 2174 break; 2175 2176 goto queue; 2177 } 2178 break; 2179 case WLAN_CATEGORY_SA_QUERY: 2180 if (len < (IEEE80211_MIN_ACTION_SIZE + 2181 sizeof(mgmt->u.action.u.sa_query))) 2182 break; 2183 2184 switch (mgmt->u.action.u.sa_query.action) { 2185 case WLAN_ACTION_SA_QUERY_REQUEST: 2186 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2187 break; 2188 ieee80211_process_sa_query_req(sdata, mgmt, len); 2189 goto handled; 2190 } 2191 break; 2192 case WLAN_CATEGORY_MESH_PLINK: 2193 if (!ieee80211_vif_is_mesh(&sdata->vif)) 2194 break; 2195 goto queue; 2196 case WLAN_CATEGORY_MESH_PATH_SEL: 2197 if (!mesh_path_sel_is_hwmp(sdata)) 2198 break; 2199 goto queue; 2200 } 2201 2202 return RX_CONTINUE; 2203 2204 invalid: 2205 status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM; 2206 /* will return in the next handlers */ 2207 return RX_CONTINUE; 2208 2209 handled: 2210 if (rx->sta) 2211 rx->sta->rx_packets++; 2212 dev_kfree_skb(rx->skb); 2213 return RX_QUEUED; 2214 2215 queue: 2216 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2217 skb_queue_tail(&sdata->skb_queue, rx->skb); 2218 ieee80211_queue_work(&local->hw, &sdata->work); 2219 if (rx->sta) 2220 rx->sta->rx_packets++; 2221 return RX_QUEUED; 2222 } 2223 2224 static ieee80211_rx_result debug_noinline 2225 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx) 2226 { 2227 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2228 2229 /* skip known-bad action frames and return them in the next handler */ 2230 if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) 2231 return RX_CONTINUE; 2232 2233 /* 2234 * Getting here means the kernel doesn't know how to handle 2235 * it, but maybe userspace does ... include returned frames 2236 * so userspace can register for those to know whether ones 2237 * it transmitted were processed or returned. 2238 */ 2239 2240 if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq, 2241 rx->skb->data, rx->skb->len, 2242 GFP_ATOMIC)) { 2243 if (rx->sta) 2244 rx->sta->rx_packets++; 2245 dev_kfree_skb(rx->skb); 2246 return RX_QUEUED; 2247 } 2248 2249 2250 return RX_CONTINUE; 2251 } 2252 2253 static ieee80211_rx_result debug_noinline 2254 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx) 2255 { 2256 struct ieee80211_local *local = rx->local; 2257 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 2258 struct sk_buff *nskb; 2259 struct ieee80211_sub_if_data *sdata = rx->sdata; 2260 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 2261 2262 if (!ieee80211_is_action(mgmt->frame_control)) 2263 return RX_CONTINUE; 2264 2265 /* 2266 * For AP mode, hostapd is responsible for handling any action 2267 * frames that we didn't handle, including returning unknown 2268 * ones. For all other modes we will return them to the sender, 2269 * setting the 0x80 bit in the action category, as required by 2270 * 802.11-2007 7.3.1.11. 2271 * Newer versions of hostapd shall also use the management frame 2272 * registration mechanisms, but older ones still use cooked 2273 * monitor interfaces so push all frames there. 2274 */ 2275 if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) && 2276 (sdata->vif.type == NL80211_IFTYPE_AP || 2277 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) 2278 return RX_DROP_MONITOR; 2279 2280 /* do not return rejected action frames */ 2281 if (mgmt->u.action.category & 0x80) 2282 return RX_DROP_UNUSABLE; 2283 2284 nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0, 2285 GFP_ATOMIC); 2286 if (nskb) { 2287 struct ieee80211_mgmt *nmgmt = (void *)nskb->data; 2288 2289 nmgmt->u.action.category |= 0x80; 2290 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN); 2291 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN); 2292 2293 memset(nskb->cb, 0, sizeof(nskb->cb)); 2294 2295 ieee80211_tx_skb(rx->sdata, nskb); 2296 } 2297 dev_kfree_skb(rx->skb); 2298 return RX_QUEUED; 2299 } 2300 2301 static ieee80211_rx_result debug_noinline 2302 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 2303 { 2304 struct ieee80211_sub_if_data *sdata = rx->sdata; 2305 ieee80211_rx_result rxs; 2306 struct ieee80211_mgmt *mgmt = (void *)rx->skb->data; 2307 __le16 stype; 2308 2309 rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb); 2310 if (rxs != RX_CONTINUE) 2311 return rxs; 2312 2313 stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE); 2314 2315 if (!ieee80211_vif_is_mesh(&sdata->vif) && 2316 sdata->vif.type != NL80211_IFTYPE_ADHOC && 2317 sdata->vif.type != NL80211_IFTYPE_STATION) 2318 return RX_DROP_MONITOR; 2319 2320 switch (stype) { 2321 case cpu_to_le16(IEEE80211_STYPE_BEACON): 2322 case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP): 2323 /* process for all: mesh, mlme, ibss */ 2324 break; 2325 case cpu_to_le16(IEEE80211_STYPE_DEAUTH): 2326 case cpu_to_le16(IEEE80211_STYPE_DISASSOC): 2327 if (is_multicast_ether_addr(mgmt->da) && 2328 !is_broadcast_ether_addr(mgmt->da)) 2329 return RX_DROP_MONITOR; 2330 2331 /* process only for station */ 2332 if (sdata->vif.type != NL80211_IFTYPE_STATION) 2333 return RX_DROP_MONITOR; 2334 break; 2335 case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ): 2336 case cpu_to_le16(IEEE80211_STYPE_AUTH): 2337 /* process only for ibss */ 2338 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 2339 return RX_DROP_MONITOR; 2340 break; 2341 default: 2342 return RX_DROP_MONITOR; 2343 } 2344 2345 /* queue up frame and kick off work to process it */ 2346 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME; 2347 skb_queue_tail(&sdata->skb_queue, rx->skb); 2348 ieee80211_queue_work(&rx->local->hw, &sdata->work); 2349 if (rx->sta) 2350 rx->sta->rx_packets++; 2351 2352 return RX_QUEUED; 2353 } 2354 2355 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 2356 struct ieee80211_rx_data *rx) 2357 { 2358 int keyidx; 2359 unsigned int hdrlen; 2360 2361 hdrlen = ieee80211_hdrlen(hdr->frame_control); 2362 if (rx->skb->len >= hdrlen + 4) 2363 keyidx = rx->skb->data[hdrlen + 3] >> 6; 2364 else 2365 keyidx = -1; 2366 2367 if (!rx->sta) { 2368 /* 2369 * Some hardware seem to generate incorrect Michael MIC 2370 * reports; ignore them to avoid triggering countermeasures. 2371 */ 2372 return; 2373 } 2374 2375 if (!ieee80211_has_protected(hdr->frame_control)) 2376 return; 2377 2378 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 2379 /* 2380 * APs with pairwise keys should never receive Michael MIC 2381 * errors for non-zero keyidx because these are reserved for 2382 * group keys and only the AP is sending real multicast 2383 * frames in the BSS. 2384 */ 2385 return; 2386 } 2387 2388 if (!ieee80211_is_data(hdr->frame_control) && 2389 !ieee80211_is_auth(hdr->frame_control)) 2390 return; 2391 2392 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 2393 GFP_ATOMIC); 2394 } 2395 2396 /* TODO: use IEEE80211_RX_FRAGMENTED */ 2397 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, 2398 struct ieee80211_rate *rate) 2399 { 2400 struct ieee80211_sub_if_data *sdata; 2401 struct ieee80211_local *local = rx->local; 2402 struct ieee80211_rtap_hdr { 2403 struct ieee80211_radiotap_header hdr; 2404 u8 flags; 2405 u8 rate_or_pad; 2406 __le16 chan_freq; 2407 __le16 chan_flags; 2408 } __packed *rthdr; 2409 struct sk_buff *skb = rx->skb, *skb2; 2410 struct net_device *prev_dev = NULL; 2411 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2412 2413 /* 2414 * If cooked monitor has been processed already, then 2415 * don't do it again. If not, set the flag. 2416 */ 2417 if (rx->flags & IEEE80211_RX_CMNTR) 2418 goto out_free_skb; 2419 rx->flags |= IEEE80211_RX_CMNTR; 2420 2421 if (skb_headroom(skb) < sizeof(*rthdr) && 2422 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 2423 goto out_free_skb; 2424 2425 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 2426 memset(rthdr, 0, sizeof(*rthdr)); 2427 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 2428 rthdr->hdr.it_present = 2429 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 2430 (1 << IEEE80211_RADIOTAP_CHANNEL)); 2431 2432 if (rate) { 2433 rthdr->rate_or_pad = rate->bitrate / 5; 2434 rthdr->hdr.it_present |= 2435 cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 2436 } 2437 rthdr->chan_freq = cpu_to_le16(status->freq); 2438 2439 if (status->band == IEEE80211_BAND_5GHZ) 2440 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 2441 IEEE80211_CHAN_5GHZ); 2442 else 2443 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 2444 IEEE80211_CHAN_2GHZ); 2445 2446 skb_set_mac_header(skb, 0); 2447 skb->ip_summed = CHECKSUM_UNNECESSARY; 2448 skb->pkt_type = PACKET_OTHERHOST; 2449 skb->protocol = htons(ETH_P_802_2); 2450 2451 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2452 if (!ieee80211_sdata_running(sdata)) 2453 continue; 2454 2455 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 2456 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 2457 continue; 2458 2459 if (prev_dev) { 2460 skb2 = skb_clone(skb, GFP_ATOMIC); 2461 if (skb2) { 2462 skb2->dev = prev_dev; 2463 netif_receive_skb(skb2); 2464 } 2465 } 2466 2467 prev_dev = sdata->dev; 2468 sdata->dev->stats.rx_packets++; 2469 sdata->dev->stats.rx_bytes += skb->len; 2470 } 2471 2472 if (prev_dev) { 2473 skb->dev = prev_dev; 2474 netif_receive_skb(skb); 2475 return; 2476 } 2477 2478 out_free_skb: 2479 dev_kfree_skb(skb); 2480 } 2481 2482 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx, 2483 ieee80211_rx_result res) 2484 { 2485 switch (res) { 2486 case RX_DROP_MONITOR: 2487 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); 2488 if (rx->sta) 2489 rx->sta->rx_dropped++; 2490 /* fall through */ 2491 case RX_CONTINUE: { 2492 struct ieee80211_rate *rate = NULL; 2493 struct ieee80211_supported_band *sband; 2494 struct ieee80211_rx_status *status; 2495 2496 status = IEEE80211_SKB_RXCB((rx->skb)); 2497 2498 sband = rx->local->hw.wiphy->bands[status->band]; 2499 if (!(status->flag & RX_FLAG_HT)) 2500 rate = &sband->bitrates[status->rate_idx]; 2501 2502 ieee80211_rx_cooked_monitor(rx, rate); 2503 break; 2504 } 2505 case RX_DROP_UNUSABLE: 2506 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop); 2507 if (rx->sta) 2508 rx->sta->rx_dropped++; 2509 dev_kfree_skb(rx->skb); 2510 break; 2511 case RX_QUEUED: 2512 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued); 2513 break; 2514 } 2515 } 2516 2517 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx) 2518 { 2519 ieee80211_rx_result res = RX_DROP_MONITOR; 2520 struct sk_buff *skb; 2521 2522 #define CALL_RXH(rxh) \ 2523 do { \ 2524 res = rxh(rx); \ 2525 if (res != RX_CONTINUE) \ 2526 goto rxh_next; \ 2527 } while (0); 2528 2529 spin_lock(&rx->local->rx_skb_queue.lock); 2530 if (rx->local->running_rx_handler) 2531 goto unlock; 2532 2533 rx->local->running_rx_handler = true; 2534 2535 while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) { 2536 spin_unlock(&rx->local->rx_skb_queue.lock); 2537 2538 /* 2539 * all the other fields are valid across frames 2540 * that belong to an aMPDU since they are on the 2541 * same TID from the same station 2542 */ 2543 rx->skb = skb; 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 .flags = 0, 2615 }; 2616 struct tid_ampdu_rx *tid_agg_rx; 2617 2618 tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 2619 if (!tid_agg_rx) 2620 return; 2621 2622 spin_lock(&tid_agg_rx->reorder_lock); 2623 ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx); 2624 spin_unlock(&tid_agg_rx->reorder_lock); 2625 2626 ieee80211_rx_handlers(&rx); 2627 } 2628 2629 /* main receive path */ 2630 2631 static int prepare_for_handlers(struct ieee80211_rx_data *rx, 2632 struct ieee80211_hdr *hdr) 2633 { 2634 struct ieee80211_sub_if_data *sdata = rx->sdata; 2635 struct sk_buff *skb = rx->skb; 2636 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2637 u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type); 2638 int multicast = is_multicast_ether_addr(hdr->addr1); 2639 2640 switch (sdata->vif.type) { 2641 case NL80211_IFTYPE_STATION: 2642 if (!bssid && !sdata->u.mgd.use_4addr) 2643 return 0; 2644 if (!multicast && 2645 compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) { 2646 if (!(sdata->dev->flags & IFF_PROMISC) || 2647 sdata->u.mgd.use_4addr) 2648 return 0; 2649 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2650 } 2651 break; 2652 case NL80211_IFTYPE_ADHOC: 2653 if (!bssid) 2654 return 0; 2655 if (ieee80211_is_beacon(hdr->frame_control)) { 2656 return 1; 2657 } 2658 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2659 if (!(status->rx_flags & IEEE80211_RX_IN_SCAN)) 2660 return 0; 2661 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2662 } else if (!multicast && 2663 compare_ether_addr(sdata->vif.addr, 2664 hdr->addr1) != 0) { 2665 if (!(sdata->dev->flags & IFF_PROMISC)) 2666 return 0; 2667 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2668 } else if (!rx->sta) { 2669 int rate_idx; 2670 if (status->flag & RX_FLAG_HT) 2671 rate_idx = 0; /* TODO: HT rates */ 2672 else 2673 rate_idx = status->rate_idx; 2674 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, 2675 hdr->addr2, BIT(rate_idx), GFP_ATOMIC); 2676 } 2677 break; 2678 case NL80211_IFTYPE_MESH_POINT: 2679 if (!multicast && 2680 compare_ether_addr(sdata->vif.addr, 2681 hdr->addr1) != 0) { 2682 if (!(sdata->dev->flags & IFF_PROMISC)) 2683 return 0; 2684 2685 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2686 } 2687 break; 2688 case NL80211_IFTYPE_AP_VLAN: 2689 case NL80211_IFTYPE_AP: 2690 if (!bssid) { 2691 if (compare_ether_addr(sdata->vif.addr, 2692 hdr->addr1)) 2693 return 0; 2694 } else if (!ieee80211_bssid_match(bssid, 2695 sdata->vif.addr)) { 2696 if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) && 2697 !ieee80211_is_beacon(hdr->frame_control)) 2698 return 0; 2699 status->rx_flags &= ~IEEE80211_RX_RA_MATCH; 2700 } 2701 break; 2702 case NL80211_IFTYPE_WDS: 2703 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2704 return 0; 2705 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2706 return 0; 2707 break; 2708 default: 2709 /* should never get here */ 2710 WARN_ON(1); 2711 break; 2712 } 2713 2714 return 1; 2715 } 2716 2717 /* 2718 * This function returns whether or not the SKB 2719 * was destined for RX processing or not, which, 2720 * if consume is true, is equivalent to whether 2721 * or not the skb was consumed. 2722 */ 2723 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx, 2724 struct sk_buff *skb, bool consume) 2725 { 2726 struct ieee80211_local *local = rx->local; 2727 struct ieee80211_sub_if_data *sdata = rx->sdata; 2728 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2729 struct ieee80211_hdr *hdr = (void *)skb->data; 2730 int prepares; 2731 2732 rx->skb = skb; 2733 status->rx_flags |= IEEE80211_RX_RA_MATCH; 2734 prepares = prepare_for_handlers(rx, hdr); 2735 2736 if (!prepares) 2737 return false; 2738 2739 if (status->flag & RX_FLAG_MMIC_ERROR) { 2740 if (status->rx_flags & IEEE80211_RX_RA_MATCH) 2741 ieee80211_rx_michael_mic_report(hdr, rx); 2742 return false; 2743 } 2744 2745 if (!consume) { 2746 skb = skb_copy(skb, GFP_ATOMIC); 2747 if (!skb) { 2748 if (net_ratelimit()) 2749 wiphy_debug(local->hw.wiphy, 2750 "failed to copy skb for %s\n", 2751 sdata->name); 2752 return true; 2753 } 2754 2755 rx->skb = skb; 2756 } 2757 2758 ieee80211_invoke_rx_handlers(rx); 2759 return true; 2760 } 2761 2762 /* 2763 * This is the actual Rx frames handler. as it blongs to Rx path it must 2764 * be called with rcu_read_lock protection. 2765 */ 2766 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2767 struct sk_buff *skb) 2768 { 2769 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2770 struct ieee80211_local *local = hw_to_local(hw); 2771 struct ieee80211_sub_if_data *sdata; 2772 struct ieee80211_hdr *hdr; 2773 __le16 fc; 2774 struct ieee80211_rx_data rx; 2775 struct ieee80211_sub_if_data *prev; 2776 struct sta_info *sta, *tmp, *prev_sta; 2777 int err = 0; 2778 2779 fc = ((struct ieee80211_hdr *)skb->data)->frame_control; 2780 memset(&rx, 0, sizeof(rx)); 2781 rx.skb = skb; 2782 rx.local = local; 2783 2784 if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) 2785 local->dot11ReceivedFragmentCount++; 2786 2787 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2788 test_bit(SCAN_SW_SCANNING, &local->scanning))) 2789 status->rx_flags |= IEEE80211_RX_IN_SCAN; 2790 2791 if (ieee80211_is_mgmt(fc)) 2792 err = skb_linearize(skb); 2793 else 2794 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); 2795 2796 if (err) { 2797 dev_kfree_skb(skb); 2798 return; 2799 } 2800 2801 hdr = (struct ieee80211_hdr *)skb->data; 2802 ieee80211_parse_qos(&rx); 2803 ieee80211_verify_alignment(&rx); 2804 2805 if (ieee80211_is_data(fc)) { 2806 prev_sta = NULL; 2807 2808 for_each_sta_info(local, hdr->addr2, sta, tmp) { 2809 if (!prev_sta) { 2810 prev_sta = sta; 2811 continue; 2812 } 2813 2814 rx.sta = prev_sta; 2815 rx.sdata = prev_sta->sdata; 2816 ieee80211_prepare_and_rx_handle(&rx, skb, false); 2817 2818 prev_sta = sta; 2819 } 2820 2821 if (prev_sta) { 2822 rx.sta = prev_sta; 2823 rx.sdata = prev_sta->sdata; 2824 2825 if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) 2826 return; 2827 goto out; 2828 } 2829 } 2830 2831 prev = NULL; 2832 2833 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2834 if (!ieee80211_sdata_running(sdata)) 2835 continue; 2836 2837 if (sdata->vif.type == NL80211_IFTYPE_MONITOR || 2838 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 2839 continue; 2840 2841 /* 2842 * frame is destined for this interface, but if it's 2843 * not also for the previous one we handle that after 2844 * the loop to avoid copying the SKB once too much 2845 */ 2846 2847 if (!prev) { 2848 prev = sdata; 2849 continue; 2850 } 2851 2852 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2853 rx.sdata = prev; 2854 ieee80211_prepare_and_rx_handle(&rx, skb, false); 2855 2856 prev = sdata; 2857 } 2858 2859 if (prev) { 2860 rx.sta = sta_info_get_bss(prev, hdr->addr2); 2861 rx.sdata = prev; 2862 2863 if (ieee80211_prepare_and_rx_handle(&rx, skb, true)) 2864 return; 2865 } 2866 2867 out: 2868 dev_kfree_skb(skb); 2869 } 2870 2871 /* 2872 * This is the receive path handler. It is called by a low level driver when an 2873 * 802.11 MPDU is received from the hardware. 2874 */ 2875 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2876 { 2877 struct ieee80211_local *local = hw_to_local(hw); 2878 struct ieee80211_rate *rate = NULL; 2879 struct ieee80211_supported_band *sband; 2880 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2881 2882 WARN_ON_ONCE(softirq_count() == 0); 2883 2884 if (WARN_ON(status->band < 0 || 2885 status->band >= IEEE80211_NUM_BANDS)) 2886 goto drop; 2887 2888 sband = local->hw.wiphy->bands[status->band]; 2889 if (WARN_ON(!sband)) 2890 goto drop; 2891 2892 /* 2893 * If we're suspending, it is possible although not too likely 2894 * that we'd be receiving frames after having already partially 2895 * quiesced the stack. We can't process such frames then since 2896 * that might, for example, cause stations to be added or other 2897 * driver callbacks be invoked. 2898 */ 2899 if (unlikely(local->quiescing || local->suspended)) 2900 goto drop; 2901 2902 /* 2903 * The same happens when we're not even started, 2904 * but that's worth a warning. 2905 */ 2906 if (WARN_ON(!local->started)) 2907 goto drop; 2908 2909 if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) { 2910 /* 2911 * Validate the rate, unless a PLCP error means that 2912 * we probably can't have a valid rate here anyway. 2913 */ 2914 2915 if (status->flag & RX_FLAG_HT) { 2916 /* 2917 * rate_idx is MCS index, which can be [0-76] 2918 * as documented on: 2919 * 2920 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n 2921 * 2922 * Anything else would be some sort of driver or 2923 * hardware error. The driver should catch hardware 2924 * errors. 2925 */ 2926 if (WARN((status->rate_idx < 0 || 2927 status->rate_idx > 76), 2928 "Rate marked as an HT rate but passed " 2929 "status->rate_idx is not " 2930 "an MCS index [0-76]: %d (0x%02x)\n", 2931 status->rate_idx, 2932 status->rate_idx)) 2933 goto drop; 2934 } else { 2935 if (WARN_ON(status->rate_idx < 0 || 2936 status->rate_idx >= sband->n_bitrates)) 2937 goto drop; 2938 rate = &sband->bitrates[status->rate_idx]; 2939 } 2940 } 2941 2942 status->rx_flags = 0; 2943 2944 /* 2945 * key references and virtual interfaces are protected using RCU 2946 * and this requires that we are in a read-side RCU section during 2947 * receive processing 2948 */ 2949 rcu_read_lock(); 2950 2951 /* 2952 * Frames with failed FCS/PLCP checksum are not returned, 2953 * all other frames are returned without radiotap header 2954 * if it was previously present. 2955 * Also, frames with less than 16 bytes are dropped. 2956 */ 2957 skb = ieee80211_rx_monitor(local, skb, rate); 2958 if (!skb) { 2959 rcu_read_unlock(); 2960 return; 2961 } 2962 2963 ieee80211_tpt_led_trig_rx(local, 2964 ((struct ieee80211_hdr *)skb->data)->frame_control, 2965 skb->len); 2966 __ieee80211_rx_handle_packet(hw, skb); 2967 2968 rcu_read_unlock(); 2969 2970 return; 2971 drop: 2972 kfree_skb(skb); 2973 } 2974 EXPORT_SYMBOL(ieee80211_rx); 2975 2976 /* This is a version of the rx handler that can be called from hard irq 2977 * context. Post the skb on the queue and schedule the tasklet */ 2978 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2979 { 2980 struct ieee80211_local *local = hw_to_local(hw); 2981 2982 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2983 2984 skb->pkt_type = IEEE80211_RX_MSG; 2985 skb_queue_tail(&local->skb_queue, skb); 2986 tasklet_schedule(&local->tasklet); 2987 } 2988 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2989