1 /* 2 * Copyright 2002-2005, Instant802 Networks, Inc. 3 * Copyright 2005-2006, Devicescape Software, Inc. 4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12 #include <linux/jiffies.h> 13 #include <linux/kernel.h> 14 #include <linux/skbuff.h> 15 #include <linux/netdevice.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rcupdate.h> 18 #include <net/mac80211.h> 19 #include <net/ieee80211_radiotap.h> 20 21 #include "ieee80211_i.h" 22 #include "driver-ops.h" 23 #include "led.h" 24 #include "mesh.h" 25 #include "wep.h" 26 #include "wpa.h" 27 #include "tkip.h" 28 #include "wme.h" 29 30 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 31 struct tid_ampdu_rx *tid_agg_rx, 32 struct sk_buff *skb, 33 struct ieee80211_rx_status *status, 34 u16 mpdu_seq_num, 35 int bar_req); 36 /* 37 * monitor mode reception 38 * 39 * This function cleans up the SKB, i.e. it removes all the stuff 40 * only useful for monitoring. 41 */ 42 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 43 struct sk_buff *skb, 44 int rtap_len) 45 { 46 skb_pull(skb, rtap_len); 47 48 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 49 if (likely(skb->len > FCS_LEN)) 50 skb_trim(skb, skb->len - FCS_LEN); 51 else { 52 /* driver bug */ 53 WARN_ON(1); 54 dev_kfree_skb(skb); 55 skb = NULL; 56 } 57 } 58 59 return skb; 60 } 61 62 static inline int should_drop_frame(struct ieee80211_rx_status *status, 63 struct sk_buff *skb, 64 int present_fcs_len, 65 int radiotap_len) 66 { 67 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 68 69 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 70 return 1; 71 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len)) 72 return 1; 73 if (ieee80211_is_ctl(hdr->frame_control) && 74 !ieee80211_is_pspoll(hdr->frame_control) && 75 !ieee80211_is_back_req(hdr->frame_control)) 76 return 1; 77 return 0; 78 } 79 80 static int 81 ieee80211_rx_radiotap_len(struct ieee80211_local *local, 82 struct ieee80211_rx_status *status) 83 { 84 int len; 85 86 /* always present fields */ 87 len = sizeof(struct ieee80211_radiotap_header) + 9; 88 89 if (status->flag & RX_FLAG_TSFT) 90 len += 8; 91 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) 92 len += 1; 93 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) 94 len += 1; 95 96 if (len & 1) /* padding for RX_FLAGS if necessary */ 97 len++; 98 99 /* make sure radiotap starts at a naturally aligned address */ 100 if (len % 8) 101 len = roundup(len, 8); 102 103 return len; 104 } 105 106 /* 107 * ieee80211_add_rx_radiotap_header - add radiotap header 108 * 109 * add a radiotap header containing all the fields which the hardware provided. 110 */ 111 static void 112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 113 struct sk_buff *skb, 114 struct ieee80211_rx_status *status, 115 struct ieee80211_rate *rate, 116 int rtap_len) 117 { 118 struct ieee80211_radiotap_header *rthdr; 119 unsigned char *pos; 120 121 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 122 memset(rthdr, 0, rtap_len); 123 124 /* radiotap header, set always present flags */ 125 rthdr->it_present = 126 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 127 (1 << IEEE80211_RADIOTAP_CHANNEL) | 128 (1 << IEEE80211_RADIOTAP_ANTENNA) | 129 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 130 rthdr->it_len = cpu_to_le16(rtap_len); 131 132 pos = (unsigned char *)(rthdr+1); 133 134 /* the order of the following fields is important */ 135 136 /* IEEE80211_RADIOTAP_TSFT */ 137 if (status->flag & RX_FLAG_TSFT) { 138 *(__le64 *)pos = cpu_to_le64(status->mactime); 139 rthdr->it_present |= 140 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 141 pos += 8; 142 } 143 144 /* IEEE80211_RADIOTAP_FLAGS */ 145 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 146 *pos |= IEEE80211_RADIOTAP_F_FCS; 147 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 148 *pos |= IEEE80211_RADIOTAP_F_BADFCS; 149 if (status->flag & RX_FLAG_SHORTPRE) 150 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; 151 pos++; 152 153 /* IEEE80211_RADIOTAP_RATE */ 154 if (status->flag & RX_FLAG_HT) { 155 /* 156 * TODO: add following information into radiotap header once 157 * suitable fields are defined for it: 158 * - MCS index (status->rate_idx) 159 * - HT40 (status->flag & RX_FLAG_40MHZ) 160 * - short-GI (status->flag & RX_FLAG_SHORT_GI) 161 */ 162 *pos = 0; 163 } else { 164 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 165 *pos = rate->bitrate / 5; 166 } 167 pos++; 168 169 /* IEEE80211_RADIOTAP_CHANNEL */ 170 *(__le16 *)pos = cpu_to_le16(status->freq); 171 pos += 2; 172 if (status->band == IEEE80211_BAND_5GHZ) 173 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | 174 IEEE80211_CHAN_5GHZ); 175 else if (rate->flags & IEEE80211_RATE_ERP_G) 176 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | 177 IEEE80211_CHAN_2GHZ); 178 else 179 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK | 180 IEEE80211_CHAN_2GHZ); 181 pos += 2; 182 183 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ 184 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { 185 *pos = status->signal; 186 rthdr->it_present |= 187 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); 188 pos++; 189 } 190 191 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */ 192 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) { 193 *pos = status->noise; 194 rthdr->it_present |= 195 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE); 196 pos++; 197 } 198 199 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ 200 201 /* IEEE80211_RADIOTAP_ANTENNA */ 202 *pos = status->antenna; 203 pos++; 204 205 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ 206 207 /* IEEE80211_RADIOTAP_RX_FLAGS */ 208 /* ensure 2 byte alignment for the 2 byte field as required */ 209 if ((pos - (unsigned char *)rthdr) & 1) 210 pos++; 211 if (status->flag & RX_FLAG_FAILED_PLCP_CRC) 212 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP); 213 pos += 2; 214 } 215 216 /* 217 * This function copies a received frame to all monitor interfaces and 218 * returns a cleaned-up SKB that no longer includes the FCS nor the 219 * radiotap header the driver might have added. 220 */ 221 static struct sk_buff * 222 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 223 struct ieee80211_rx_status *status, 224 struct ieee80211_rate *rate) 225 { 226 struct ieee80211_sub_if_data *sdata; 227 int needed_headroom = 0; 228 struct sk_buff *skb, *skb2; 229 struct net_device *prev_dev = NULL; 230 int present_fcs_len = 0; 231 int rtap_len = 0; 232 233 /* 234 * First, we may need to make a copy of the skb because 235 * (1) we need to modify it for radiotap (if not present), and 236 * (2) the other RX handlers will modify the skb we got. 237 * 238 * We don't need to, of course, if we aren't going to return 239 * the SKB because it has a bad FCS/PLCP checksum. 240 */ 241 if (status->flag & RX_FLAG_RADIOTAP) 242 rtap_len = ieee80211_get_radiotap_len(origskb->data); 243 else 244 /* room for the radiotap header based on driver features */ 245 needed_headroom = ieee80211_rx_radiotap_len(local, status); 246 247 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 248 present_fcs_len = FCS_LEN; 249 250 if (!local->monitors) { 251 if (should_drop_frame(status, origskb, present_fcs_len, 252 rtap_len)) { 253 dev_kfree_skb(origskb); 254 return NULL; 255 } 256 257 return remove_monitor_info(local, origskb, rtap_len); 258 } 259 260 if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) { 261 /* only need to expand headroom if necessary */ 262 skb = origskb; 263 origskb = NULL; 264 265 /* 266 * This shouldn't trigger often because most devices have an 267 * RX header they pull before we get here, and that should 268 * be big enough for our radiotap information. We should 269 * probably export the length to drivers so that we can have 270 * them allocate enough headroom to start with. 271 */ 272 if (skb_headroom(skb) < needed_headroom && 273 pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) { 274 dev_kfree_skb(skb); 275 return NULL; 276 } 277 } else { 278 /* 279 * Need to make a copy and possibly remove radiotap header 280 * and FCS from the original. 281 */ 282 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC); 283 284 origskb = remove_monitor_info(local, origskb, rtap_len); 285 286 if (!skb) 287 return origskb; 288 } 289 290 /* if necessary, prepend radiotap information */ 291 if (!(status->flag & RX_FLAG_RADIOTAP)) 292 ieee80211_add_rx_radiotap_header(local, skb, status, rate, 293 needed_headroom); 294 295 skb_reset_mac_header(skb); 296 skb->ip_summed = CHECKSUM_UNNECESSARY; 297 skb->pkt_type = PACKET_OTHERHOST; 298 skb->protocol = htons(ETH_P_802_2); 299 300 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 301 if (!netif_running(sdata->dev)) 302 continue; 303 304 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) 305 continue; 306 307 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 308 continue; 309 310 if (prev_dev) { 311 skb2 = skb_clone(skb, GFP_ATOMIC); 312 if (skb2) { 313 skb2->dev = prev_dev; 314 netif_rx(skb2); 315 } 316 } 317 318 prev_dev = sdata->dev; 319 sdata->dev->stats.rx_packets++; 320 sdata->dev->stats.rx_bytes += skb->len; 321 } 322 323 if (prev_dev) { 324 skb->dev = prev_dev; 325 netif_rx(skb); 326 } else 327 dev_kfree_skb(skb); 328 329 return origskb; 330 } 331 332 333 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 334 { 335 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 336 int tid; 337 338 /* does the frame have a qos control field? */ 339 if (ieee80211_is_data_qos(hdr->frame_control)) { 340 u8 *qc = ieee80211_get_qos_ctl(hdr); 341 /* frame has qos control */ 342 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 343 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 344 rx->flags |= IEEE80211_RX_AMSDU; 345 else 346 rx->flags &= ~IEEE80211_RX_AMSDU; 347 } else { 348 /* 349 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 350 * 351 * Sequence numbers for management frames, QoS data 352 * frames with a broadcast/multicast address in the 353 * Address 1 field, and all non-QoS data frames sent 354 * by QoS STAs are assigned using an additional single 355 * modulo-4096 counter, [...] 356 * 357 * We also use that counter for non-QoS STAs. 358 */ 359 tid = NUM_RX_DATA_QUEUES - 1; 360 } 361 362 rx->queue = tid; 363 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 364 * For now, set skb->priority to 0 for other cases. */ 365 rx->skb->priority = (tid > 7) ? 0 : tid; 366 } 367 368 /** 369 * DOC: Packet alignment 370 * 371 * Drivers always need to pass packets that are aligned to two-byte boundaries 372 * to the stack. 373 * 374 * Additionally, should, if possible, align the payload data in a way that 375 * guarantees that the contained IP header is aligned to a four-byte 376 * boundary. In the case of regular frames, this simply means aligning the 377 * payload to a four-byte boundary (because either the IP header is directly 378 * contained, or IV/RFC1042 headers that have a length divisible by four are 379 * in front of it). 380 * 381 * With A-MSDU frames, however, the payload data address must yield two modulo 382 * four because there are 14-byte 802.3 headers within the A-MSDU frames that 383 * push the IP header further back to a multiple of four again. Thankfully, the 384 * specs were sane enough this time around to require padding each A-MSDU 385 * subframe to a length that is a multiple of four. 386 * 387 * Padding like Atheros hardware adds which is inbetween the 802.11 header and 388 * the payload is not supported, the driver is required to move the 802.11 389 * header to be directly in front of the payload in that case. 390 */ 391 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) 392 { 393 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 394 int hdrlen; 395 396 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT 397 return; 398 #endif 399 400 if (WARN_ONCE((unsigned long)rx->skb->data & 1, 401 "unaligned packet at 0x%p\n", rx->skb->data)) 402 return; 403 404 if (!ieee80211_is_data_present(hdr->frame_control)) 405 return; 406 407 hdrlen = ieee80211_hdrlen(hdr->frame_control); 408 if (rx->flags & IEEE80211_RX_AMSDU) 409 hdrlen += ETH_HLEN; 410 WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3, 411 "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen); 412 } 413 414 415 /* rx handlers */ 416 417 static ieee80211_rx_result debug_noinline 418 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 419 { 420 struct ieee80211_local *local = rx->local; 421 struct sk_buff *skb = rx->skb; 422 423 if (unlikely(local->hw_scanning)) 424 return ieee80211_scan_rx(rx->sdata, skb, rx->status); 425 426 if (unlikely(local->sw_scanning)) { 427 /* drop all the other packets during a software scan anyway */ 428 if (ieee80211_scan_rx(rx->sdata, skb, rx->status) 429 != RX_QUEUED) 430 dev_kfree_skb(skb); 431 return RX_QUEUED; 432 } 433 434 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { 435 /* scanning finished during invoking of handlers */ 436 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 437 return RX_DROP_UNUSABLE; 438 } 439 440 return RX_CONTINUE; 441 } 442 443 444 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) 445 { 446 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 447 448 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) 449 return 0; 450 451 return ieee80211_is_robust_mgmt_frame(hdr); 452 } 453 454 455 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) 456 { 457 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 458 459 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) 460 return 0; 461 462 return ieee80211_is_robust_mgmt_frame(hdr); 463 } 464 465 466 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ 467 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) 468 { 469 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; 470 struct ieee80211_mmie *mmie; 471 472 if (skb->len < 24 + sizeof(*mmie) || 473 !is_multicast_ether_addr(hdr->da)) 474 return -1; 475 476 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) 477 return -1; /* not a robust management frame */ 478 479 mmie = (struct ieee80211_mmie *) 480 (skb->data + skb->len - sizeof(*mmie)); 481 if (mmie->element_id != WLAN_EID_MMIE || 482 mmie->length != sizeof(*mmie) - 2) 483 return -1; 484 485 return le16_to_cpu(mmie->key_id); 486 } 487 488 489 static ieee80211_rx_result 490 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 491 { 492 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 493 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 494 495 if (ieee80211_is_data(hdr->frame_control)) { 496 if (!ieee80211_has_a4(hdr->frame_control)) 497 return RX_DROP_MONITOR; 498 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0) 499 return RX_DROP_MONITOR; 500 } 501 502 /* If there is not an established peer link and this is not a peer link 503 * establisment frame, beacon or probe, drop the frame. 504 */ 505 506 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 507 struct ieee80211_mgmt *mgmt; 508 509 if (!ieee80211_is_mgmt(hdr->frame_control)) 510 return RX_DROP_MONITOR; 511 512 if (ieee80211_is_action(hdr->frame_control)) { 513 mgmt = (struct ieee80211_mgmt *)hdr; 514 if (mgmt->u.action.category != PLINK_CATEGORY) 515 return RX_DROP_MONITOR; 516 return RX_CONTINUE; 517 } 518 519 if (ieee80211_is_probe_req(hdr->frame_control) || 520 ieee80211_is_probe_resp(hdr->frame_control) || 521 ieee80211_is_beacon(hdr->frame_control)) 522 return RX_CONTINUE; 523 524 return RX_DROP_MONITOR; 525 526 } 527 528 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 529 530 if (ieee80211_is_data(hdr->frame_control) && 531 is_multicast_ether_addr(hdr->addr1) && 532 mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata)) 533 return RX_DROP_MONITOR; 534 #undef msh_h_get 535 536 return RX_CONTINUE; 537 } 538 539 540 static ieee80211_rx_result debug_noinline 541 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 542 { 543 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 544 545 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 546 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 547 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 548 rx->sta->last_seq_ctrl[rx->queue] == 549 hdr->seq_ctrl)) { 550 if (rx->flags & IEEE80211_RX_RA_MATCH) { 551 rx->local->dot11FrameDuplicateCount++; 552 rx->sta->num_duplicates++; 553 } 554 return RX_DROP_MONITOR; 555 } else 556 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 557 } 558 559 if (unlikely(rx->skb->len < 16)) { 560 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 561 return RX_DROP_MONITOR; 562 } 563 564 /* Drop disallowed frame classes based on STA auth/assoc state; 565 * IEEE 802.11, Chap 5.5. 566 * 567 * mac80211 filters only based on association state, i.e. it drops 568 * Class 3 frames from not associated stations. hostapd sends 569 * deauth/disassoc frames when needed. In addition, hostapd is 570 * responsible for filtering on both auth and assoc states. 571 */ 572 573 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 574 return ieee80211_rx_mesh_check(rx); 575 576 if (unlikely((ieee80211_is_data(hdr->frame_control) || 577 ieee80211_is_pspoll(hdr->frame_control)) && 578 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 579 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 580 if ((!ieee80211_has_fromds(hdr->frame_control) && 581 !ieee80211_has_tods(hdr->frame_control) && 582 ieee80211_is_data(hdr->frame_control)) || 583 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 584 /* Drop IBSS frames and frames for other hosts 585 * silently. */ 586 return RX_DROP_MONITOR; 587 } 588 589 return RX_DROP_MONITOR; 590 } 591 592 return RX_CONTINUE; 593 } 594 595 596 static ieee80211_rx_result debug_noinline 597 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 598 { 599 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 600 int keyidx; 601 int hdrlen; 602 ieee80211_rx_result result = RX_DROP_UNUSABLE; 603 struct ieee80211_key *stakey = NULL; 604 int mmie_keyidx = -1; 605 606 /* 607 * Key selection 101 608 * 609 * There are four types of keys: 610 * - GTK (group keys) 611 * - IGTK (group keys for management frames) 612 * - PTK (pairwise keys) 613 * - STK (station-to-station pairwise keys) 614 * 615 * When selecting a key, we have to distinguish between multicast 616 * (including broadcast) and unicast frames, the latter can only 617 * use PTKs and STKs while the former always use GTKs and IGTKs. 618 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 619 * unicast frames can also use key indices like GTKs. Hence, if we 620 * don't have a PTK/STK we check the key index for a WEP key. 621 * 622 * Note that in a regular BSS, multicast frames are sent by the 623 * AP only, associated stations unicast the frame to the AP first 624 * which then multicasts it on their behalf. 625 * 626 * There is also a slight problem in IBSS mode: GTKs are negotiated 627 * with each station, that is something we don't currently handle. 628 * The spec seems to expect that one negotiates the same key with 629 * every station but there's no such requirement; VLANs could be 630 * possible. 631 */ 632 633 /* 634 * No point in finding a key and decrypting if the frame is neither 635 * addressed to us nor a multicast frame. 636 */ 637 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 638 return RX_CONTINUE; 639 640 if (rx->sta) 641 stakey = rcu_dereference(rx->sta->key); 642 643 if (!ieee80211_has_protected(hdr->frame_control)) 644 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 645 646 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 647 rx->key = stakey; 648 /* Skip decryption if the frame is not protected. */ 649 if (!ieee80211_has_protected(hdr->frame_control)) 650 return RX_CONTINUE; 651 } else if (mmie_keyidx >= 0) { 652 /* Broadcast/multicast robust management frame / BIP */ 653 if ((rx->status->flag & RX_FLAG_DECRYPTED) && 654 (rx->status->flag & RX_FLAG_IV_STRIPPED)) 655 return RX_CONTINUE; 656 657 if (mmie_keyidx < NUM_DEFAULT_KEYS || 658 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 659 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 660 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 661 } else if (!ieee80211_has_protected(hdr->frame_control)) { 662 /* 663 * The frame was not protected, so skip decryption. However, we 664 * need to set rx->key if there is a key that could have been 665 * used so that the frame may be dropped if encryption would 666 * have been expected. 667 */ 668 struct ieee80211_key *key = NULL; 669 if (ieee80211_is_mgmt(hdr->frame_control) && 670 is_multicast_ether_addr(hdr->addr1) && 671 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 672 rx->key = key; 673 else if ((key = rcu_dereference(rx->sdata->default_key))) 674 rx->key = key; 675 return RX_CONTINUE; 676 } else { 677 /* 678 * The device doesn't give us the IV so we won't be 679 * able to look up the key. That's ok though, we 680 * don't need to decrypt the frame, we just won't 681 * be able to keep statistics accurate. 682 * Except for key threshold notifications, should 683 * we somehow allow the driver to tell us which key 684 * the hardware used if this flag is set? 685 */ 686 if ((rx->status->flag & RX_FLAG_DECRYPTED) && 687 (rx->status->flag & RX_FLAG_IV_STRIPPED)) 688 return RX_CONTINUE; 689 690 hdrlen = ieee80211_hdrlen(hdr->frame_control); 691 692 if (rx->skb->len < 8 + hdrlen) 693 return RX_DROP_UNUSABLE; /* TODO: count this? */ 694 695 /* 696 * no need to call ieee80211_wep_get_keyidx, 697 * it verifies a bunch of things we've done already 698 */ 699 keyidx = rx->skb->data[hdrlen + 3] >> 6; 700 701 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 702 703 /* 704 * RSNA-protected unicast frames should always be sent with 705 * pairwise or station-to-station keys, but for WEP we allow 706 * using a key index as well. 707 */ 708 if (rx->key && rx->key->conf.alg != ALG_WEP && 709 !is_multicast_ether_addr(hdr->addr1)) 710 rx->key = NULL; 711 } 712 713 if (rx->key) { 714 rx->key->tx_rx_count++; 715 /* TODO: add threshold stuff again */ 716 } else { 717 return RX_DROP_MONITOR; 718 } 719 720 /* Check for weak IVs if possible */ 721 if (rx->sta && rx->key->conf.alg == ALG_WEP && 722 ieee80211_is_data(hdr->frame_control) && 723 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) || 724 !(rx->status->flag & RX_FLAG_DECRYPTED)) && 725 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 726 rx->sta->wep_weak_iv_count++; 727 728 switch (rx->key->conf.alg) { 729 case ALG_WEP: 730 result = ieee80211_crypto_wep_decrypt(rx); 731 break; 732 case ALG_TKIP: 733 result = ieee80211_crypto_tkip_decrypt(rx); 734 break; 735 case ALG_CCMP: 736 result = ieee80211_crypto_ccmp_decrypt(rx); 737 break; 738 case ALG_AES_CMAC: 739 result = ieee80211_crypto_aes_cmac_decrypt(rx); 740 break; 741 } 742 743 /* either the frame has been decrypted or will be dropped */ 744 rx->status->flag |= RX_FLAG_DECRYPTED; 745 746 return result; 747 } 748 749 static ieee80211_rx_result debug_noinline 750 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 751 { 752 struct ieee80211_local *local; 753 struct ieee80211_hdr *hdr; 754 struct sk_buff *skb; 755 756 local = rx->local; 757 skb = rx->skb; 758 hdr = (struct ieee80211_hdr *) skb->data; 759 760 if (!local->pspolling) 761 return RX_CONTINUE; 762 763 if (!ieee80211_has_fromds(hdr->frame_control)) 764 /* this is not from AP */ 765 return RX_CONTINUE; 766 767 if (!ieee80211_is_data(hdr->frame_control)) 768 return RX_CONTINUE; 769 770 if (!ieee80211_has_moredata(hdr->frame_control)) { 771 /* AP has no more frames buffered for us */ 772 local->pspolling = false; 773 return RX_CONTINUE; 774 } 775 776 /* more data bit is set, let's request a new frame from the AP */ 777 ieee80211_send_pspoll(local, rx->sdata); 778 779 return RX_CONTINUE; 780 } 781 782 static void ap_sta_ps_start(struct sta_info *sta) 783 { 784 struct ieee80211_sub_if_data *sdata = sta->sdata; 785 struct ieee80211_local *local = sdata->local; 786 787 atomic_inc(&sdata->bss->num_sta_ps); 788 set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL); 789 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta); 790 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 791 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 792 sdata->dev->name, sta->sta.addr, sta->sta.aid); 793 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 794 } 795 796 static int ap_sta_ps_end(struct sta_info *sta) 797 { 798 struct ieee80211_sub_if_data *sdata = sta->sdata; 799 struct ieee80211_local *local = sdata->local; 800 int sent, buffered; 801 802 atomic_dec(&sdata->bss->num_sta_ps); 803 804 clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL); 805 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta); 806 807 if (!skb_queue_empty(&sta->ps_tx_buf)) 808 sta_info_clear_tim_bit(sta); 809 810 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 811 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 812 sdata->dev->name, sta->sta.addr, sta->sta.aid); 813 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 814 815 /* Send all buffered frames to the station */ 816 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered); 817 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf); 818 sent += buffered; 819 local->total_ps_buffered -= buffered; 820 821 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 822 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 823 "since STA not sleeping anymore\n", sdata->dev->name, 824 sta->sta.addr, sta->sta.aid, sent - buffered, buffered); 825 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 826 827 return sent; 828 } 829 830 static ieee80211_rx_result debug_noinline 831 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 832 { 833 struct sta_info *sta = rx->sta; 834 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 835 836 if (!sta) 837 return RX_CONTINUE; 838 839 /* Update last_rx only for IBSS packets which are for the current 840 * BSSID to avoid keeping the current IBSS network alive in cases where 841 * other STAs are using different BSSID. */ 842 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 843 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 844 NL80211_IFTYPE_ADHOC); 845 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) 846 sta->last_rx = jiffies; 847 } else 848 if (!is_multicast_ether_addr(hdr->addr1) || 849 rx->sdata->vif.type == NL80211_IFTYPE_STATION) { 850 /* Update last_rx only for unicast frames in order to prevent 851 * the Probe Request frames (the only broadcast frames from a 852 * STA in infrastructure mode) from keeping a connection alive. 853 * Mesh beacons will update last_rx when if they are found to 854 * match the current local configuration when processed. 855 */ 856 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION && 857 ieee80211_is_beacon(hdr->frame_control)) { 858 rx->sdata->u.mgd.last_beacon = jiffies; 859 } else 860 sta->last_rx = jiffies; 861 } 862 863 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 864 return RX_CONTINUE; 865 866 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 867 ieee80211_sta_rx_notify(rx->sdata, hdr); 868 869 sta->rx_fragments++; 870 sta->rx_bytes += rx->skb->len; 871 sta->last_signal = rx->status->signal; 872 sta->last_qual = rx->status->qual; 873 sta->last_noise = rx->status->noise; 874 875 /* 876 * Change STA power saving mode only at the end of a frame 877 * exchange sequence. 878 */ 879 if (!ieee80211_has_morefrags(hdr->frame_control) && 880 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 881 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 882 if (test_sta_flags(sta, WLAN_STA_PS)) { 883 /* 884 * Ignore doze->wake transitions that are 885 * indicated by non-data frames, the standard 886 * is unclear here, but for example going to 887 * PS mode and then scanning would cause a 888 * doze->wake transition for the probe request, 889 * and that is clearly undesirable. 890 */ 891 if (ieee80211_is_data(hdr->frame_control) && 892 !ieee80211_has_pm(hdr->frame_control)) 893 rx->sent_ps_buffered += ap_sta_ps_end(sta); 894 } else { 895 if (ieee80211_has_pm(hdr->frame_control)) 896 ap_sta_ps_start(sta); 897 } 898 } 899 900 /* Drop data::nullfunc frames silently, since they are used only to 901 * control station power saving mode. */ 902 if (ieee80211_is_nullfunc(hdr->frame_control)) { 903 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 904 /* Update counter and free packet here to avoid counting this 905 * as a dropped packed. */ 906 sta->rx_packets++; 907 dev_kfree_skb(rx->skb); 908 return RX_QUEUED; 909 } 910 911 return RX_CONTINUE; 912 } /* ieee80211_rx_h_sta_process */ 913 914 static inline struct ieee80211_fragment_entry * 915 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 916 unsigned int frag, unsigned int seq, int rx_queue, 917 struct sk_buff **skb) 918 { 919 struct ieee80211_fragment_entry *entry; 920 int idx; 921 922 idx = sdata->fragment_next; 923 entry = &sdata->fragments[sdata->fragment_next++]; 924 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 925 sdata->fragment_next = 0; 926 927 if (!skb_queue_empty(&entry->skb_list)) { 928 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 929 struct ieee80211_hdr *hdr = 930 (struct ieee80211_hdr *) entry->skb_list.next->data; 931 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 932 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 933 "addr1=%pM addr2=%pM\n", 934 sdata->dev->name, idx, 935 jiffies - entry->first_frag_time, entry->seq, 936 entry->last_frag, hdr->addr1, hdr->addr2); 937 #endif 938 __skb_queue_purge(&entry->skb_list); 939 } 940 941 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 942 *skb = NULL; 943 entry->first_frag_time = jiffies; 944 entry->seq = seq; 945 entry->rx_queue = rx_queue; 946 entry->last_frag = frag; 947 entry->ccmp = 0; 948 entry->extra_len = 0; 949 950 return entry; 951 } 952 953 static inline struct ieee80211_fragment_entry * 954 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 955 unsigned int frag, unsigned int seq, 956 int rx_queue, struct ieee80211_hdr *hdr) 957 { 958 struct ieee80211_fragment_entry *entry; 959 int i, idx; 960 961 idx = sdata->fragment_next; 962 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 963 struct ieee80211_hdr *f_hdr; 964 965 idx--; 966 if (idx < 0) 967 idx = IEEE80211_FRAGMENT_MAX - 1; 968 969 entry = &sdata->fragments[idx]; 970 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 971 entry->rx_queue != rx_queue || 972 entry->last_frag + 1 != frag) 973 continue; 974 975 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 976 977 /* 978 * Check ftype and addresses are equal, else check next fragment 979 */ 980 if (((hdr->frame_control ^ f_hdr->frame_control) & 981 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 982 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 983 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 984 continue; 985 986 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 987 __skb_queue_purge(&entry->skb_list); 988 continue; 989 } 990 return entry; 991 } 992 993 return NULL; 994 } 995 996 static ieee80211_rx_result debug_noinline 997 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 998 { 999 struct ieee80211_hdr *hdr; 1000 u16 sc; 1001 __le16 fc; 1002 unsigned int frag, seq; 1003 struct ieee80211_fragment_entry *entry; 1004 struct sk_buff *skb; 1005 1006 hdr = (struct ieee80211_hdr *)rx->skb->data; 1007 fc = hdr->frame_control; 1008 sc = le16_to_cpu(hdr->seq_ctrl); 1009 frag = sc & IEEE80211_SCTL_FRAG; 1010 1011 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1012 (rx->skb)->len < 24 || 1013 is_multicast_ether_addr(hdr->addr1))) { 1014 /* not fragmented */ 1015 goto out; 1016 } 1017 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1018 1019 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1020 1021 if (frag == 0) { 1022 /* This is the first fragment of a new frame. */ 1023 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1024 rx->queue, &(rx->skb)); 1025 if (rx->key && rx->key->conf.alg == ALG_CCMP && 1026 ieee80211_has_protected(fc)) { 1027 /* Store CCMP PN so that we can verify that the next 1028 * fragment has a sequential PN value. */ 1029 entry->ccmp = 1; 1030 memcpy(entry->last_pn, 1031 rx->key->u.ccmp.rx_pn[rx->queue], 1032 CCMP_PN_LEN); 1033 } 1034 return RX_QUEUED; 1035 } 1036 1037 /* This is a fragment for a frame that should already be pending in 1038 * fragment cache. Add this fragment to the end of the pending entry. 1039 */ 1040 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1041 if (!entry) { 1042 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1043 return RX_DROP_MONITOR; 1044 } 1045 1046 /* Verify that MPDUs within one MSDU have sequential PN values. 1047 * (IEEE 802.11i, 8.3.3.4.5) */ 1048 if (entry->ccmp) { 1049 int i; 1050 u8 pn[CCMP_PN_LEN], *rpn; 1051 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 1052 return RX_DROP_UNUSABLE; 1053 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1054 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1055 pn[i]++; 1056 if (pn[i]) 1057 break; 1058 } 1059 rpn = rx->key->u.ccmp.rx_pn[rx->queue]; 1060 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1061 return RX_DROP_UNUSABLE; 1062 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1063 } 1064 1065 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1066 __skb_queue_tail(&entry->skb_list, rx->skb); 1067 entry->last_frag = frag; 1068 entry->extra_len += rx->skb->len; 1069 if (ieee80211_has_morefrags(fc)) { 1070 rx->skb = NULL; 1071 return RX_QUEUED; 1072 } 1073 1074 rx->skb = __skb_dequeue(&entry->skb_list); 1075 if (skb_tailroom(rx->skb) < entry->extra_len) { 1076 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1077 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1078 GFP_ATOMIC))) { 1079 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1080 __skb_queue_purge(&entry->skb_list); 1081 return RX_DROP_UNUSABLE; 1082 } 1083 } 1084 while ((skb = __skb_dequeue(&entry->skb_list))) { 1085 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1086 dev_kfree_skb(skb); 1087 } 1088 1089 /* Complete frame has been reassembled - process it now */ 1090 rx->flags |= IEEE80211_RX_FRAGMENTED; 1091 1092 out: 1093 if (rx->sta) 1094 rx->sta->rx_packets++; 1095 if (is_multicast_ether_addr(hdr->addr1)) 1096 rx->local->dot11MulticastReceivedFrameCount++; 1097 else 1098 ieee80211_led_rx(rx->local); 1099 return RX_CONTINUE; 1100 } 1101 1102 static ieee80211_rx_result debug_noinline 1103 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1104 { 1105 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1106 struct sk_buff *skb; 1107 int no_pending_pkts; 1108 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1109 1110 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1111 !(rx->flags & IEEE80211_RX_RA_MATCH))) 1112 return RX_CONTINUE; 1113 1114 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1115 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1116 return RX_DROP_UNUSABLE; 1117 1118 skb = skb_dequeue(&rx->sta->tx_filtered); 1119 if (!skb) { 1120 skb = skb_dequeue(&rx->sta->ps_tx_buf); 1121 if (skb) 1122 rx->local->total_ps_buffered--; 1123 } 1124 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) && 1125 skb_queue_empty(&rx->sta->ps_tx_buf); 1126 1127 if (skb) { 1128 struct ieee80211_hdr *hdr = 1129 (struct ieee80211_hdr *) skb->data; 1130 1131 /* 1132 * Tell TX path to send one frame even though the STA may 1133 * still remain is PS mode after this frame exchange. 1134 */ 1135 set_sta_flags(rx->sta, WLAN_STA_PSPOLL); 1136 1137 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1138 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n", 1139 rx->sta->sta.addr, rx->sta->sta.aid, 1140 skb_queue_len(&rx->sta->ps_tx_buf)); 1141 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1142 1143 /* Use MoreData flag to indicate whether there are more 1144 * buffered frames for this STA */ 1145 if (no_pending_pkts) 1146 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 1147 else 1148 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 1149 1150 dev_queue_xmit(skb); 1151 1152 if (no_pending_pkts) 1153 sta_info_clear_tim_bit(rx->sta); 1154 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1155 } else if (!rx->sent_ps_buffered) { 1156 /* 1157 * FIXME: This can be the result of a race condition between 1158 * us expiring a frame and the station polling for it. 1159 * Should we send it a null-func frame indicating we 1160 * have nothing buffered for it? 1161 */ 1162 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 1163 "though there are no buffered frames for it\n", 1164 rx->dev->name, rx->sta->sta.addr); 1165 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1166 } 1167 1168 /* Free PS Poll skb here instead of returning RX_DROP that would 1169 * count as an dropped frame. */ 1170 dev_kfree_skb(rx->skb); 1171 1172 return RX_QUEUED; 1173 } 1174 1175 static ieee80211_rx_result debug_noinline 1176 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1177 { 1178 u8 *data = rx->skb->data; 1179 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1180 1181 if (!ieee80211_is_data_qos(hdr->frame_control)) 1182 return RX_CONTINUE; 1183 1184 /* remove the qos control field, update frame type and meta-data */ 1185 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1186 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1187 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1188 /* change frame type to non QOS */ 1189 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1190 1191 return RX_CONTINUE; 1192 } 1193 1194 static int 1195 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1196 { 1197 if (unlikely(!rx->sta || 1198 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1199 return -EACCES; 1200 1201 return 0; 1202 } 1203 1204 static int 1205 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1206 { 1207 /* 1208 * Pass through unencrypted frames if the hardware has 1209 * decrypted them already. 1210 */ 1211 if (rx->status->flag & RX_FLAG_DECRYPTED) 1212 return 0; 1213 1214 /* Drop unencrypted frames if key is set. */ 1215 if (unlikely(!ieee80211_has_protected(fc) && 1216 !ieee80211_is_nullfunc(fc) && 1217 ieee80211_is_data(fc) && 1218 (rx->key || rx->sdata->drop_unencrypted))) 1219 return -EACCES; 1220 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1221 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1222 rx->key)) 1223 return -EACCES; 1224 /* BIP does not use Protected field, so need to check MMIE */ 1225 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) 1226 && ieee80211_get_mmie_keyidx(rx->skb) < 0 && 1227 rx->key)) 1228 return -EACCES; 1229 /* 1230 * When using MFP, Action frames are not allowed prior to 1231 * having configured keys. 1232 */ 1233 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1234 ieee80211_is_robust_mgmt_frame( 1235 (struct ieee80211_hdr *) rx->skb->data))) 1236 return -EACCES; 1237 } 1238 1239 return 0; 1240 } 1241 1242 static int 1243 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1244 { 1245 struct net_device *dev = rx->dev; 1246 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1247 1248 return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type); 1249 } 1250 1251 /* 1252 * requires that rx->skb is a frame with ethernet header 1253 */ 1254 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1255 { 1256 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1257 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1258 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1259 1260 /* 1261 * Allow EAPOL frames to us/the PAE group address regardless 1262 * of whether the frame was encrypted or not. 1263 */ 1264 if (ehdr->h_proto == htons(ETH_P_PAE) && 1265 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 || 1266 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1267 return true; 1268 1269 if (ieee80211_802_1x_port_control(rx) || 1270 ieee80211_drop_unencrypted(rx, fc)) 1271 return false; 1272 1273 return true; 1274 } 1275 1276 /* 1277 * requires that rx->skb is a frame with ethernet header 1278 */ 1279 static void 1280 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1281 { 1282 struct net_device *dev = rx->dev; 1283 struct ieee80211_local *local = rx->local; 1284 struct sk_buff *skb, *xmit_skb; 1285 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1286 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1287 struct sta_info *dsta; 1288 1289 skb = rx->skb; 1290 xmit_skb = NULL; 1291 1292 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1293 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1294 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1295 (rx->flags & IEEE80211_RX_RA_MATCH)) { 1296 if (is_multicast_ether_addr(ehdr->h_dest)) { 1297 /* 1298 * send multicast frames both to higher layers in 1299 * local net stack and back to the wireless medium 1300 */ 1301 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1302 if (!xmit_skb && net_ratelimit()) 1303 printk(KERN_DEBUG "%s: failed to clone " 1304 "multicast frame\n", dev->name); 1305 } else { 1306 dsta = sta_info_get(local, skb->data); 1307 if (dsta && dsta->sdata->dev == dev) { 1308 /* 1309 * The destination station is associated to 1310 * this AP (in this VLAN), so send the frame 1311 * directly to it and do not pass it to local 1312 * net stack. 1313 */ 1314 xmit_skb = skb; 1315 skb = NULL; 1316 } 1317 } 1318 } 1319 1320 if (skb) { 1321 int align __maybe_unused; 1322 1323 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 1324 /* 1325 * 'align' will only take the values 0 or 2 here 1326 * since all frames are required to be aligned 1327 * to 2-byte boundaries when being passed to 1328 * mac80211. That also explains the __skb_push() 1329 * below. 1330 */ 1331 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1332 if (align) { 1333 if (WARN_ON(skb_headroom(skb) < 3)) { 1334 dev_kfree_skb(skb); 1335 skb = NULL; 1336 } else { 1337 u8 *data = skb->data; 1338 size_t len = skb->len; 1339 u8 *new = __skb_push(skb, align); 1340 memmove(new, data, len); 1341 __skb_trim(skb, len); 1342 } 1343 } 1344 #endif 1345 1346 if (skb) { 1347 /* deliver to local stack */ 1348 skb->protocol = eth_type_trans(skb, dev); 1349 memset(skb->cb, 0, sizeof(skb->cb)); 1350 netif_rx(skb); 1351 } 1352 } 1353 1354 if (xmit_skb) { 1355 /* send to wireless media */ 1356 xmit_skb->protocol = htons(ETH_P_802_3); 1357 skb_reset_network_header(xmit_skb); 1358 skb_reset_mac_header(xmit_skb); 1359 dev_queue_xmit(xmit_skb); 1360 } 1361 } 1362 1363 static ieee80211_rx_result debug_noinline 1364 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1365 { 1366 struct net_device *dev = rx->dev; 1367 struct ieee80211_local *local = rx->local; 1368 u16 ethertype; 1369 u8 *payload; 1370 struct sk_buff *skb = rx->skb, *frame = NULL; 1371 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1372 __le16 fc = hdr->frame_control; 1373 const struct ethhdr *eth; 1374 int remaining, err; 1375 u8 dst[ETH_ALEN]; 1376 u8 src[ETH_ALEN]; 1377 1378 if (unlikely(!ieee80211_is_data(fc))) 1379 return RX_CONTINUE; 1380 1381 if (unlikely(!ieee80211_is_data_present(fc))) 1382 return RX_DROP_MONITOR; 1383 1384 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1385 return RX_CONTINUE; 1386 1387 err = __ieee80211_data_to_8023(rx); 1388 if (unlikely(err)) 1389 return RX_DROP_UNUSABLE; 1390 1391 skb->dev = dev; 1392 1393 dev->stats.rx_packets++; 1394 dev->stats.rx_bytes += skb->len; 1395 1396 /* skip the wrapping header */ 1397 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr)); 1398 if (!eth) 1399 return RX_DROP_UNUSABLE; 1400 1401 while (skb != frame) { 1402 u8 padding; 1403 __be16 len = eth->h_proto; 1404 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len); 1405 1406 remaining = skb->len; 1407 memcpy(dst, eth->h_dest, ETH_ALEN); 1408 memcpy(src, eth->h_source, ETH_ALEN); 1409 1410 padding = ((4 - subframe_len) & 0x3); 1411 /* the last MSDU has no padding */ 1412 if (subframe_len > remaining) 1413 return RX_DROP_UNUSABLE; 1414 1415 skb_pull(skb, sizeof(struct ethhdr)); 1416 /* if last subframe reuse skb */ 1417 if (remaining <= subframe_len + padding) 1418 frame = skb; 1419 else { 1420 /* 1421 * Allocate and reserve two bytes more for payload 1422 * alignment since sizeof(struct ethhdr) is 14. 1423 */ 1424 frame = dev_alloc_skb( 1425 ALIGN(local->hw.extra_tx_headroom, 4) + 1426 subframe_len + 2); 1427 1428 if (frame == NULL) 1429 return RX_DROP_UNUSABLE; 1430 1431 skb_reserve(frame, 1432 ALIGN(local->hw.extra_tx_headroom, 4) + 1433 sizeof(struct ethhdr) + 2); 1434 memcpy(skb_put(frame, ntohs(len)), skb->data, 1435 ntohs(len)); 1436 1437 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) + 1438 padding); 1439 if (!eth) { 1440 dev_kfree_skb(frame); 1441 return RX_DROP_UNUSABLE; 1442 } 1443 } 1444 1445 skb_reset_network_header(frame); 1446 frame->dev = dev; 1447 frame->priority = skb->priority; 1448 rx->skb = frame; 1449 1450 payload = frame->data; 1451 ethertype = (payload[6] << 8) | payload[7]; 1452 1453 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && 1454 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || 1455 compare_ether_addr(payload, 1456 bridge_tunnel_header) == 0)) { 1457 /* remove RFC1042 or Bridge-Tunnel 1458 * encapsulation and replace EtherType */ 1459 skb_pull(frame, 6); 1460 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1461 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1462 } else { 1463 memcpy(skb_push(frame, sizeof(__be16)), 1464 &len, sizeof(__be16)); 1465 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1466 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1467 } 1468 1469 if (!ieee80211_frame_allowed(rx, fc)) { 1470 if (skb == frame) /* last frame */ 1471 return RX_DROP_UNUSABLE; 1472 dev_kfree_skb(frame); 1473 continue; 1474 } 1475 1476 ieee80211_deliver_skb(rx); 1477 } 1478 1479 return RX_QUEUED; 1480 } 1481 1482 #ifdef CONFIG_MAC80211_MESH 1483 static ieee80211_rx_result 1484 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1485 { 1486 struct ieee80211_hdr *hdr; 1487 struct ieee80211s_hdr *mesh_hdr; 1488 unsigned int hdrlen; 1489 struct sk_buff *skb = rx->skb, *fwd_skb; 1490 1491 hdr = (struct ieee80211_hdr *) skb->data; 1492 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1493 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1494 1495 if (!ieee80211_is_data(hdr->frame_control)) 1496 return RX_CONTINUE; 1497 1498 if (!mesh_hdr->ttl) 1499 /* illegal frame */ 1500 return RX_DROP_MONITOR; 1501 1502 if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){ 1503 struct ieee80211_sub_if_data *sdata; 1504 struct mesh_path *mppath; 1505 1506 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1507 rcu_read_lock(); 1508 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata); 1509 if (!mppath) { 1510 mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata); 1511 } else { 1512 spin_lock_bh(&mppath->state_lock); 1513 mppath->exp_time = jiffies; 1514 if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0) 1515 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN); 1516 spin_unlock_bh(&mppath->state_lock); 1517 } 1518 rcu_read_unlock(); 1519 } 1520 1521 if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0) 1522 return RX_CONTINUE; 1523 1524 mesh_hdr->ttl--; 1525 1526 if (rx->flags & IEEE80211_RX_RA_MATCH) { 1527 if (!mesh_hdr->ttl) 1528 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1529 dropped_frames_ttl); 1530 else { 1531 struct ieee80211_hdr *fwd_hdr; 1532 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1533 1534 if (!fwd_skb && net_ratelimit()) 1535 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1536 rx->dev->name); 1537 1538 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1539 /* 1540 * Save TA to addr1 to send TA a path error if a 1541 * suitable next hop is not found 1542 */ 1543 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN); 1544 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN); 1545 fwd_skb->dev = rx->local->mdev; 1546 fwd_skb->iif = rx->dev->ifindex; 1547 dev_queue_xmit(fwd_skb); 1548 } 1549 } 1550 1551 if (is_multicast_ether_addr(hdr->addr3) || 1552 rx->dev->flags & IFF_PROMISC) 1553 return RX_CONTINUE; 1554 else 1555 return RX_DROP_MONITOR; 1556 } 1557 #endif 1558 1559 static ieee80211_rx_result debug_noinline 1560 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1561 { 1562 struct net_device *dev = rx->dev; 1563 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1564 __le16 fc = hdr->frame_control; 1565 int err; 1566 1567 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1568 return RX_CONTINUE; 1569 1570 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1571 return RX_DROP_MONITOR; 1572 1573 err = __ieee80211_data_to_8023(rx); 1574 if (unlikely(err)) 1575 return RX_DROP_UNUSABLE; 1576 1577 if (!ieee80211_frame_allowed(rx, fc)) 1578 return RX_DROP_MONITOR; 1579 1580 rx->skb->dev = dev; 1581 1582 dev->stats.rx_packets++; 1583 dev->stats.rx_bytes += rx->skb->len; 1584 1585 ieee80211_deliver_skb(rx); 1586 1587 return RX_QUEUED; 1588 } 1589 1590 static ieee80211_rx_result debug_noinline 1591 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx) 1592 { 1593 struct ieee80211_local *local = rx->local; 1594 struct ieee80211_hw *hw = &local->hw; 1595 struct sk_buff *skb = rx->skb; 1596 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1597 struct tid_ampdu_rx *tid_agg_rx; 1598 u16 start_seq_num; 1599 u16 tid; 1600 1601 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1602 return RX_CONTINUE; 1603 1604 if (ieee80211_is_back_req(bar->frame_control)) { 1605 if (!rx->sta) 1606 return RX_CONTINUE; 1607 tid = le16_to_cpu(bar->control) >> 12; 1608 if (rx->sta->ampdu_mlme.tid_state_rx[tid] 1609 != HT_AGG_STATE_OPERATIONAL) 1610 return RX_CONTINUE; 1611 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; 1612 1613 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4; 1614 1615 /* reset session timer */ 1616 if (tid_agg_rx->timeout) 1617 mod_timer(&tid_agg_rx->session_timer, 1618 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1619 1620 /* manage reordering buffer according to requested */ 1621 /* sequence number */ 1622 rcu_read_lock(); 1623 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, NULL, 1624 start_seq_num, 1); 1625 rcu_read_unlock(); 1626 return RX_DROP_UNUSABLE; 1627 } 1628 1629 return RX_CONTINUE; 1630 } 1631 1632 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 1633 struct ieee80211_mgmt *mgmt, 1634 size_t len) 1635 { 1636 struct ieee80211_local *local = sdata->local; 1637 struct sk_buff *skb; 1638 struct ieee80211_mgmt *resp; 1639 1640 if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) { 1641 /* Not to own unicast address */ 1642 return; 1643 } 1644 1645 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 1646 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 1647 /* Not from the current AP. */ 1648 return; 1649 } 1650 1651 if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) { 1652 /* Association in progress; ignore SA Query */ 1653 return; 1654 } 1655 1656 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 1657 /* Too short SA Query request frame */ 1658 return; 1659 } 1660 1661 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 1662 if (skb == NULL) 1663 return; 1664 1665 skb_reserve(skb, local->hw.extra_tx_headroom); 1666 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 1667 memset(resp, 0, 24); 1668 memcpy(resp->da, mgmt->sa, ETH_ALEN); 1669 memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN); 1670 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 1671 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 1672 IEEE80211_STYPE_ACTION); 1673 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 1674 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 1675 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 1676 memcpy(resp->u.action.u.sa_query.trans_id, 1677 mgmt->u.action.u.sa_query.trans_id, 1678 WLAN_SA_QUERY_TR_ID_LEN); 1679 1680 ieee80211_tx_skb(sdata, skb, 1); 1681 } 1682 1683 static ieee80211_rx_result debug_noinline 1684 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 1685 { 1686 struct ieee80211_local *local = rx->local; 1687 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1688 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1689 struct ieee80211_bss *bss; 1690 int len = rx->skb->len; 1691 1692 if (!ieee80211_is_action(mgmt->frame_control)) 1693 return RX_CONTINUE; 1694 1695 if (!rx->sta) 1696 return RX_DROP_MONITOR; 1697 1698 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1699 return RX_DROP_MONITOR; 1700 1701 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1702 return RX_DROP_MONITOR; 1703 1704 /* all categories we currently handle have action_code */ 1705 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1706 return RX_DROP_MONITOR; 1707 1708 switch (mgmt->u.action.category) { 1709 case WLAN_CATEGORY_BACK: 1710 /* 1711 * The aggregation code is not prepared to handle 1712 * anything but STA/AP due to the BSSID handling; 1713 * IBSS could work in the code but isn't supported 1714 * by drivers or the standard. 1715 */ 1716 if (sdata->vif.type != NL80211_IFTYPE_STATION && 1717 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 1718 sdata->vif.type != NL80211_IFTYPE_AP) 1719 return RX_DROP_MONITOR; 1720 1721 switch (mgmt->u.action.u.addba_req.action_code) { 1722 case WLAN_ACTION_ADDBA_REQ: 1723 if (len < (IEEE80211_MIN_ACTION_SIZE + 1724 sizeof(mgmt->u.action.u.addba_req))) 1725 return RX_DROP_MONITOR; 1726 ieee80211_process_addba_request(local, rx->sta, mgmt, len); 1727 break; 1728 case WLAN_ACTION_ADDBA_RESP: 1729 if (len < (IEEE80211_MIN_ACTION_SIZE + 1730 sizeof(mgmt->u.action.u.addba_resp))) 1731 return RX_DROP_MONITOR; 1732 ieee80211_process_addba_resp(local, rx->sta, mgmt, len); 1733 break; 1734 case WLAN_ACTION_DELBA: 1735 if (len < (IEEE80211_MIN_ACTION_SIZE + 1736 sizeof(mgmt->u.action.u.delba))) 1737 return RX_DROP_MONITOR; 1738 ieee80211_process_delba(sdata, rx->sta, mgmt, len); 1739 break; 1740 } 1741 break; 1742 case WLAN_CATEGORY_SPECTRUM_MGMT: 1743 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 1744 return RX_DROP_MONITOR; 1745 1746 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1747 return RX_DROP_MONITOR; 1748 1749 switch (mgmt->u.action.u.measurement.action_code) { 1750 case WLAN_ACTION_SPCT_MSR_REQ: 1751 if (len < (IEEE80211_MIN_ACTION_SIZE + 1752 sizeof(mgmt->u.action.u.measurement))) 1753 return RX_DROP_MONITOR; 1754 ieee80211_process_measurement_req(sdata, mgmt, len); 1755 break; 1756 case WLAN_ACTION_SPCT_CHL_SWITCH: 1757 if (len < (IEEE80211_MIN_ACTION_SIZE + 1758 sizeof(mgmt->u.action.u.chan_switch))) 1759 return RX_DROP_MONITOR; 1760 1761 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1762 return RX_DROP_MONITOR; 1763 1764 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 1765 return RX_DROP_MONITOR; 1766 1767 bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid, 1768 local->hw.conf.channel->center_freq, 1769 sdata->u.mgd.ssid, 1770 sdata->u.mgd.ssid_len); 1771 if (!bss) 1772 return RX_DROP_MONITOR; 1773 1774 ieee80211_sta_process_chanswitch(sdata, 1775 &mgmt->u.action.u.chan_switch.sw_elem, bss); 1776 ieee80211_rx_bss_put(local, bss); 1777 break; 1778 } 1779 break; 1780 case WLAN_CATEGORY_SA_QUERY: 1781 if (len < (IEEE80211_MIN_ACTION_SIZE + 1782 sizeof(mgmt->u.action.u.sa_query))) 1783 return RX_DROP_MONITOR; 1784 switch (mgmt->u.action.u.sa_query.action) { 1785 case WLAN_ACTION_SA_QUERY_REQUEST: 1786 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1787 return RX_DROP_MONITOR; 1788 ieee80211_process_sa_query_req(sdata, mgmt, len); 1789 break; 1790 case WLAN_ACTION_SA_QUERY_RESPONSE: 1791 /* 1792 * SA Query response is currently only used in AP mode 1793 * and it is processed in user space. 1794 */ 1795 return RX_CONTINUE; 1796 } 1797 break; 1798 default: 1799 return RX_CONTINUE; 1800 } 1801 1802 rx->sta->rx_packets++; 1803 dev_kfree_skb(rx->skb); 1804 return RX_QUEUED; 1805 } 1806 1807 static ieee80211_rx_result debug_noinline 1808 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 1809 { 1810 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1811 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1812 1813 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1814 return RX_DROP_MONITOR; 1815 1816 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1817 return RX_DROP_MONITOR; 1818 1819 if (ieee80211_vif_is_mesh(&sdata->vif)) 1820 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status); 1821 1822 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 1823 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status); 1824 1825 if (sdata->vif.type == NL80211_IFTYPE_STATION) 1826 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status); 1827 1828 return RX_DROP_MONITOR; 1829 } 1830 1831 static void ieee80211_rx_michael_mic_report(struct net_device *dev, 1832 struct ieee80211_hdr *hdr, 1833 struct ieee80211_rx_data *rx) 1834 { 1835 int keyidx; 1836 unsigned int hdrlen; 1837 1838 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1839 if (rx->skb->len >= hdrlen + 4) 1840 keyidx = rx->skb->data[hdrlen + 3] >> 6; 1841 else 1842 keyidx = -1; 1843 1844 if (!rx->sta) { 1845 /* 1846 * Some hardware seem to generate incorrect Michael MIC 1847 * reports; ignore them to avoid triggering countermeasures. 1848 */ 1849 goto ignore; 1850 } 1851 1852 if (!ieee80211_has_protected(hdr->frame_control)) 1853 goto ignore; 1854 1855 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 1856 /* 1857 * APs with pairwise keys should never receive Michael MIC 1858 * errors for non-zero keyidx because these are reserved for 1859 * group keys and only the AP is sending real multicast 1860 * frames in the BSS. 1861 */ 1862 goto ignore; 1863 } 1864 1865 if (!ieee80211_is_data(hdr->frame_control) && 1866 !ieee80211_is_auth(hdr->frame_control)) 1867 goto ignore; 1868 1869 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL); 1870 ignore: 1871 dev_kfree_skb(rx->skb); 1872 rx->skb = NULL; 1873 } 1874 1875 /* TODO: use IEEE80211_RX_FRAGMENTED */ 1876 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx) 1877 { 1878 struct ieee80211_sub_if_data *sdata; 1879 struct ieee80211_local *local = rx->local; 1880 struct ieee80211_rtap_hdr { 1881 struct ieee80211_radiotap_header hdr; 1882 u8 flags; 1883 u8 rate; 1884 __le16 chan_freq; 1885 __le16 chan_flags; 1886 } __attribute__ ((packed)) *rthdr; 1887 struct sk_buff *skb = rx->skb, *skb2; 1888 struct net_device *prev_dev = NULL; 1889 struct ieee80211_rx_status *status = rx->status; 1890 1891 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED) 1892 goto out_free_skb; 1893 1894 if (skb_headroom(skb) < sizeof(*rthdr) && 1895 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 1896 goto out_free_skb; 1897 1898 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 1899 memset(rthdr, 0, sizeof(*rthdr)); 1900 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 1901 rthdr->hdr.it_present = 1902 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 1903 (1 << IEEE80211_RADIOTAP_RATE) | 1904 (1 << IEEE80211_RADIOTAP_CHANNEL)); 1905 1906 rthdr->rate = rx->rate->bitrate / 5; 1907 rthdr->chan_freq = cpu_to_le16(status->freq); 1908 1909 if (status->band == IEEE80211_BAND_5GHZ) 1910 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 1911 IEEE80211_CHAN_5GHZ); 1912 else 1913 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 1914 IEEE80211_CHAN_2GHZ); 1915 1916 skb_set_mac_header(skb, 0); 1917 skb->ip_summed = CHECKSUM_UNNECESSARY; 1918 skb->pkt_type = PACKET_OTHERHOST; 1919 skb->protocol = htons(ETH_P_802_2); 1920 1921 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 1922 if (!netif_running(sdata->dev)) 1923 continue; 1924 1925 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 1926 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 1927 continue; 1928 1929 if (prev_dev) { 1930 skb2 = skb_clone(skb, GFP_ATOMIC); 1931 if (skb2) { 1932 skb2->dev = prev_dev; 1933 netif_rx(skb2); 1934 } 1935 } 1936 1937 prev_dev = sdata->dev; 1938 sdata->dev->stats.rx_packets++; 1939 sdata->dev->stats.rx_bytes += skb->len; 1940 } 1941 1942 if (prev_dev) { 1943 skb->dev = prev_dev; 1944 netif_rx(skb); 1945 skb = NULL; 1946 } else 1947 goto out_free_skb; 1948 1949 rx->flags |= IEEE80211_RX_CMNTR_REPORTED; 1950 return; 1951 1952 out_free_skb: 1953 dev_kfree_skb(skb); 1954 } 1955 1956 1957 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 1958 struct ieee80211_rx_data *rx, 1959 struct sk_buff *skb) 1960 { 1961 ieee80211_rx_result res = RX_DROP_MONITOR; 1962 1963 rx->skb = skb; 1964 rx->sdata = sdata; 1965 rx->dev = sdata->dev; 1966 1967 #define CALL_RXH(rxh) \ 1968 do { \ 1969 res = rxh(rx); \ 1970 if (res != RX_CONTINUE) \ 1971 goto rxh_done; \ 1972 } while (0); 1973 1974 CALL_RXH(ieee80211_rx_h_passive_scan) 1975 CALL_RXH(ieee80211_rx_h_check) 1976 CALL_RXH(ieee80211_rx_h_decrypt) 1977 CALL_RXH(ieee80211_rx_h_check_more_data) 1978 CALL_RXH(ieee80211_rx_h_sta_process) 1979 CALL_RXH(ieee80211_rx_h_defragment) 1980 CALL_RXH(ieee80211_rx_h_ps_poll) 1981 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 1982 /* must be after MMIC verify so header is counted in MPDU mic */ 1983 CALL_RXH(ieee80211_rx_h_remove_qos_control) 1984 CALL_RXH(ieee80211_rx_h_amsdu) 1985 #ifdef CONFIG_MAC80211_MESH 1986 if (ieee80211_vif_is_mesh(&sdata->vif)) 1987 CALL_RXH(ieee80211_rx_h_mesh_fwding); 1988 #endif 1989 CALL_RXH(ieee80211_rx_h_data) 1990 CALL_RXH(ieee80211_rx_h_ctrl) 1991 CALL_RXH(ieee80211_rx_h_action) 1992 CALL_RXH(ieee80211_rx_h_mgmt) 1993 1994 #undef CALL_RXH 1995 1996 rxh_done: 1997 switch (res) { 1998 case RX_DROP_MONITOR: 1999 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2000 if (rx->sta) 2001 rx->sta->rx_dropped++; 2002 /* fall through */ 2003 case RX_CONTINUE: 2004 ieee80211_rx_cooked_monitor(rx); 2005 break; 2006 case RX_DROP_UNUSABLE: 2007 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2008 if (rx->sta) 2009 rx->sta->rx_dropped++; 2010 dev_kfree_skb(rx->skb); 2011 break; 2012 case RX_QUEUED: 2013 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 2014 break; 2015 } 2016 } 2017 2018 /* main receive path */ 2019 2020 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 2021 struct ieee80211_rx_data *rx, 2022 struct ieee80211_hdr *hdr) 2023 { 2024 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type); 2025 int multicast = is_multicast_ether_addr(hdr->addr1); 2026 2027 switch (sdata->vif.type) { 2028 case NL80211_IFTYPE_STATION: 2029 if (!bssid) 2030 return 0; 2031 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) { 2032 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2033 return 0; 2034 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2035 } else if (!multicast && 2036 compare_ether_addr(sdata->dev->dev_addr, 2037 hdr->addr1) != 0) { 2038 if (!(sdata->dev->flags & IFF_PROMISC)) 2039 return 0; 2040 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2041 } 2042 break; 2043 case NL80211_IFTYPE_ADHOC: 2044 if (!bssid) 2045 return 0; 2046 if (ieee80211_is_beacon(hdr->frame_control)) { 2047 return 1; 2048 } 2049 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2050 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2051 return 0; 2052 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2053 } else if (!multicast && 2054 compare_ether_addr(sdata->dev->dev_addr, 2055 hdr->addr1) != 0) { 2056 if (!(sdata->dev->flags & IFF_PROMISC)) 2057 return 0; 2058 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2059 } else if (!rx->sta) { 2060 int rate_idx; 2061 if (rx->status->flag & RX_FLAG_HT) 2062 rate_idx = 0; /* TODO: HT rates */ 2063 else 2064 rate_idx = rx->status->rate_idx; 2065 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2, 2066 BIT(rate_idx)); 2067 } 2068 break; 2069 case NL80211_IFTYPE_MESH_POINT: 2070 if (!multicast && 2071 compare_ether_addr(sdata->dev->dev_addr, 2072 hdr->addr1) != 0) { 2073 if (!(sdata->dev->flags & IFF_PROMISC)) 2074 return 0; 2075 2076 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2077 } 2078 break; 2079 case NL80211_IFTYPE_AP_VLAN: 2080 case NL80211_IFTYPE_AP: 2081 if (!bssid) { 2082 if (compare_ether_addr(sdata->dev->dev_addr, 2083 hdr->addr1)) 2084 return 0; 2085 } else if (!ieee80211_bssid_match(bssid, 2086 sdata->dev->dev_addr)) { 2087 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2088 return 0; 2089 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2090 } 2091 break; 2092 case NL80211_IFTYPE_WDS: 2093 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2094 return 0; 2095 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2096 return 0; 2097 break; 2098 case NL80211_IFTYPE_MONITOR: 2099 /* take everything */ 2100 break; 2101 case NL80211_IFTYPE_UNSPECIFIED: 2102 case __NL80211_IFTYPE_AFTER_LAST: 2103 /* should never get here */ 2104 WARN_ON(1); 2105 break; 2106 } 2107 2108 return 1; 2109 } 2110 2111 /* 2112 * This is the actual Rx frames handler. as it blongs to Rx path it must 2113 * be called with rcu_read_lock protection. 2114 */ 2115 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2116 struct sk_buff *skb, 2117 struct ieee80211_rx_status *status, 2118 struct ieee80211_rate *rate) 2119 { 2120 struct ieee80211_local *local = hw_to_local(hw); 2121 struct ieee80211_sub_if_data *sdata; 2122 struct ieee80211_hdr *hdr; 2123 struct ieee80211_rx_data rx; 2124 int prepares; 2125 struct ieee80211_sub_if_data *prev = NULL; 2126 struct sk_buff *skb_new; 2127 2128 hdr = (struct ieee80211_hdr *)skb->data; 2129 memset(&rx, 0, sizeof(rx)); 2130 rx.skb = skb; 2131 rx.local = local; 2132 2133 rx.status = status; 2134 rx.rate = rate; 2135 2136 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control)) 2137 local->dot11ReceivedFragmentCount++; 2138 2139 rx.sta = sta_info_get(local, hdr->addr2); 2140 if (rx.sta) { 2141 rx.sdata = rx.sta->sdata; 2142 rx.dev = rx.sta->sdata->dev; 2143 } 2144 2145 if ((status->flag & RX_FLAG_MMIC_ERROR)) { 2146 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx); 2147 return; 2148 } 2149 2150 if (unlikely(local->sw_scanning || local->hw_scanning)) 2151 rx.flags |= IEEE80211_RX_IN_SCAN; 2152 2153 ieee80211_parse_qos(&rx); 2154 ieee80211_verify_alignment(&rx); 2155 2156 skb = rx.skb; 2157 2158 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2159 if (!netif_running(sdata->dev)) 2160 continue; 2161 2162 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) 2163 continue; 2164 2165 rx.flags |= IEEE80211_RX_RA_MATCH; 2166 prepares = prepare_for_handlers(sdata, &rx, hdr); 2167 2168 if (!prepares) 2169 continue; 2170 2171 /* 2172 * frame is destined for this interface, but if it's not 2173 * also for the previous one we handle that after the 2174 * loop to avoid copying the SKB once too much 2175 */ 2176 2177 if (!prev) { 2178 prev = sdata; 2179 continue; 2180 } 2181 2182 /* 2183 * frame was destined for the previous interface 2184 * so invoke RX handlers for it 2185 */ 2186 2187 skb_new = skb_copy(skb, GFP_ATOMIC); 2188 if (!skb_new) { 2189 if (net_ratelimit()) 2190 printk(KERN_DEBUG "%s: failed to copy " 2191 "multicast frame for %s\n", 2192 wiphy_name(local->hw.wiphy), 2193 prev->dev->name); 2194 continue; 2195 } 2196 ieee80211_invoke_rx_handlers(prev, &rx, skb_new); 2197 prev = sdata; 2198 } 2199 if (prev) 2200 ieee80211_invoke_rx_handlers(prev, &rx, skb); 2201 else 2202 dev_kfree_skb(skb); 2203 } 2204 2205 #define SEQ_MODULO 0x1000 2206 #define SEQ_MASK 0xfff 2207 2208 static inline int seq_less(u16 sq1, u16 sq2) 2209 { 2210 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); 2211 } 2212 2213 static inline u16 seq_inc(u16 sq) 2214 { 2215 return (sq + 1) & SEQ_MASK; 2216 } 2217 2218 static inline u16 seq_sub(u16 sq1, u16 sq2) 2219 { 2220 return (sq1 - sq2) & SEQ_MASK; 2221 } 2222 2223 2224 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, 2225 struct tid_ampdu_rx *tid_agg_rx, 2226 int index) 2227 { 2228 struct ieee80211_supported_band *sband; 2229 struct ieee80211_rate *rate; 2230 struct ieee80211_rx_status status; 2231 2232 if (!tid_agg_rx->reorder_buf[index]) 2233 goto no_frame; 2234 2235 /* release the reordered frames to stack */ 2236 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb, sizeof(status)); 2237 sband = hw->wiphy->bands[status.band]; 2238 if (status.flag & RX_FLAG_HT) 2239 rate = sband->bitrates; /* TODO: HT rates */ 2240 else 2241 rate = &sband->bitrates[status.rate_idx]; 2242 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index], 2243 &status, rate); 2244 tid_agg_rx->stored_mpdu_num--; 2245 tid_agg_rx->reorder_buf[index] = NULL; 2246 2247 no_frame: 2248 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 2249 } 2250 2251 2252 /* 2253 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If 2254 * the skb was added to the buffer longer than this time ago, the earlier 2255 * frames that have not yet been received are assumed to be lost and the skb 2256 * can be released for processing. This may also release other skb's from the 2257 * reorder buffer if there are no additional gaps between the frames. 2258 */ 2259 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) 2260 2261 /* 2262 * As it function blongs to Rx path it must be called with 2263 * the proper rcu_read_lock protection for its flow. 2264 */ 2265 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 2266 struct tid_ampdu_rx *tid_agg_rx, 2267 struct sk_buff *skb, 2268 struct ieee80211_rx_status *rxstatus, 2269 u16 mpdu_seq_num, 2270 int bar_req) 2271 { 2272 u16 head_seq_num, buf_size; 2273 int index; 2274 2275 buf_size = tid_agg_rx->buf_size; 2276 head_seq_num = tid_agg_rx->head_seq_num; 2277 2278 /* frame with out of date sequence number */ 2279 if (seq_less(mpdu_seq_num, head_seq_num)) { 2280 dev_kfree_skb(skb); 2281 return 1; 2282 } 2283 2284 /* if frame sequence number exceeds our buffering window size or 2285 * block Ack Request arrived - release stored frames */ 2286 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) { 2287 /* new head to the ordering buffer */ 2288 if (bar_req) 2289 head_seq_num = mpdu_seq_num; 2290 else 2291 head_seq_num = 2292 seq_inc(seq_sub(mpdu_seq_num, buf_size)); 2293 /* release stored frames up to new head to stack */ 2294 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 2295 index = seq_sub(tid_agg_rx->head_seq_num, 2296 tid_agg_rx->ssn) 2297 % tid_agg_rx->buf_size; 2298 ieee80211_release_reorder_frame(hw, tid_agg_rx, 2299 index); 2300 } 2301 if (bar_req) 2302 return 1; 2303 } 2304 2305 /* now the new frame is always in the range of the reordering */ 2306 /* buffer window */ 2307 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) 2308 % tid_agg_rx->buf_size; 2309 /* check if we already stored this frame */ 2310 if (tid_agg_rx->reorder_buf[index]) { 2311 dev_kfree_skb(skb); 2312 return 1; 2313 } 2314 2315 /* if arrived mpdu is in the right order and nothing else stored */ 2316 /* release it immediately */ 2317 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 2318 tid_agg_rx->stored_mpdu_num == 0) { 2319 tid_agg_rx->head_seq_num = 2320 seq_inc(tid_agg_rx->head_seq_num); 2321 return 0; 2322 } 2323 2324 /* put the frame in the reordering buffer */ 2325 tid_agg_rx->reorder_buf[index] = skb; 2326 tid_agg_rx->reorder_time[index] = jiffies; 2327 memcpy(tid_agg_rx->reorder_buf[index]->cb, rxstatus, 2328 sizeof(*rxstatus)); 2329 tid_agg_rx->stored_mpdu_num++; 2330 /* release the buffer until next missing frame */ 2331 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) 2332 % tid_agg_rx->buf_size; 2333 if (!tid_agg_rx->reorder_buf[index] && 2334 tid_agg_rx->stored_mpdu_num > 1) { 2335 /* 2336 * No buffers ready to be released, but check whether any 2337 * frames in the reorder buffer have timed out. 2338 */ 2339 int j; 2340 int skipped = 1; 2341 for (j = (index + 1) % tid_agg_rx->buf_size; j != index; 2342 j = (j + 1) % tid_agg_rx->buf_size) { 2343 if (tid_agg_rx->reorder_buf[j] == NULL) { 2344 skipped++; 2345 continue; 2346 } 2347 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + 2348 HZ / 10)) 2349 break; 2350 2351 #ifdef CONFIG_MAC80211_HT_DEBUG 2352 if (net_ratelimit()) 2353 printk(KERN_DEBUG "%s: release an RX reorder " 2354 "frame due to timeout on earlier " 2355 "frames\n", 2356 wiphy_name(hw->wiphy)); 2357 #endif 2358 ieee80211_release_reorder_frame(hw, tid_agg_rx, j); 2359 2360 /* 2361 * Increment the head seq# also for the skipped slots. 2362 */ 2363 tid_agg_rx->head_seq_num = 2364 (tid_agg_rx->head_seq_num + skipped) & 2365 SEQ_MASK; 2366 skipped = 0; 2367 } 2368 } else while (tid_agg_rx->reorder_buf[index]) { 2369 ieee80211_release_reorder_frame(hw, tid_agg_rx, index); 2370 index = seq_sub(tid_agg_rx->head_seq_num, 2371 tid_agg_rx->ssn) % tid_agg_rx->buf_size; 2372 } 2373 return 1; 2374 } 2375 2376 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local, 2377 struct sk_buff *skb, 2378 struct ieee80211_rx_status *status) 2379 { 2380 struct ieee80211_hw *hw = &local->hw; 2381 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 2382 struct sta_info *sta; 2383 struct tid_ampdu_rx *tid_agg_rx; 2384 u16 sc; 2385 u16 mpdu_seq_num; 2386 u8 ret = 0; 2387 int tid; 2388 2389 sta = sta_info_get(local, hdr->addr2); 2390 if (!sta) 2391 return ret; 2392 2393 /* filter the QoS data rx stream according to 2394 * STA/TID and check if this STA/TID is on aggregation */ 2395 if (!ieee80211_is_data_qos(hdr->frame_control)) 2396 goto end_reorder; 2397 2398 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 2399 2400 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) 2401 goto end_reorder; 2402 2403 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; 2404 2405 /* qos null data frames are excluded */ 2406 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 2407 goto end_reorder; 2408 2409 /* new un-ordered ampdu frame - process it */ 2410 2411 /* reset session timer */ 2412 if (tid_agg_rx->timeout) 2413 mod_timer(&tid_agg_rx->session_timer, 2414 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 2415 2416 /* if this mpdu is fragmented - terminate rx aggregation session */ 2417 sc = le16_to_cpu(hdr->seq_ctrl); 2418 if (sc & IEEE80211_SCTL_FRAG) { 2419 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr, 2420 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP); 2421 ret = 1; 2422 goto end_reorder; 2423 } 2424 2425 /* according to mpdu sequence number deal with reordering buffer */ 2426 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 2427 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, status, 2428 mpdu_seq_num, 0); 2429 end_reorder: 2430 return ret; 2431 } 2432 2433 /* 2434 * This is the receive path handler. It is called by a low level driver when an 2435 * 802.11 MPDU is received from the hardware. 2436 */ 2437 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, 2438 struct ieee80211_rx_status *status) 2439 { 2440 struct ieee80211_local *local = hw_to_local(hw); 2441 struct ieee80211_rate *rate = NULL; 2442 struct ieee80211_supported_band *sband; 2443 2444 if (status->band < 0 || 2445 status->band >= IEEE80211_NUM_BANDS) { 2446 WARN_ON(1); 2447 return; 2448 } 2449 2450 sband = local->hw.wiphy->bands[status->band]; 2451 if (!sband) { 2452 WARN_ON(1); 2453 return; 2454 } 2455 2456 if (status->flag & RX_FLAG_HT) { 2457 /* rate_idx is MCS index */ 2458 if (WARN_ON(status->rate_idx < 0 || 2459 status->rate_idx >= 76)) 2460 return; 2461 /* HT rates are not in the table - use the highest legacy rate 2462 * for now since other parts of mac80211 may not yet be fully 2463 * MCS aware. */ 2464 rate = &sband->bitrates[sband->n_bitrates - 1]; 2465 } else { 2466 if (WARN_ON(status->rate_idx < 0 || 2467 status->rate_idx >= sband->n_bitrates)) 2468 return; 2469 rate = &sband->bitrates[status->rate_idx]; 2470 } 2471 2472 /* 2473 * key references and virtual interfaces are protected using RCU 2474 * and this requires that we are in a read-side RCU section during 2475 * receive processing 2476 */ 2477 rcu_read_lock(); 2478 2479 /* 2480 * Frames with failed FCS/PLCP checksum are not returned, 2481 * all other frames are returned without radiotap header 2482 * if it was previously present. 2483 * Also, frames with less than 16 bytes are dropped. 2484 */ 2485 skb = ieee80211_rx_monitor(local, skb, status, rate); 2486 if (!skb) { 2487 rcu_read_unlock(); 2488 return; 2489 } 2490 2491 /* 2492 * In theory, the block ack reordering should happen after duplicate 2493 * removal (ieee80211_rx_h_check(), which is an RX handler). As such, 2494 * the call to ieee80211_rx_reorder_ampdu() should really be moved to 2495 * happen as a new RX handler between ieee80211_rx_h_check and 2496 * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for 2497 * the time being, the call can be here since RX reorder buf processing 2498 * will implicitly skip duplicates. We could, in theory at least, 2499 * process frames that ieee80211_rx_h_passive_scan would drop (e.g., 2500 * frames from other than operational channel), but that should not 2501 * happen in normal networks. 2502 */ 2503 if (!ieee80211_rx_reorder_ampdu(local, skb, status)) 2504 __ieee80211_rx_handle_packet(hw, skb, status, rate); 2505 2506 rcu_read_unlock(); 2507 } 2508 EXPORT_SYMBOL(__ieee80211_rx); 2509 2510 /* This is a version of the rx handler that can be called from hard irq 2511 * context. Post the skb on the queue and schedule the tasklet */ 2512 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, 2513 struct ieee80211_rx_status *status) 2514 { 2515 struct ieee80211_local *local = hw_to_local(hw); 2516 2517 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2518 2519 skb->dev = local->mdev; 2520 /* copy status into skb->cb for use by tasklet */ 2521 memcpy(skb->cb, status, sizeof(*status)); 2522 skb->pkt_type = IEEE80211_RX_MSG; 2523 skb_queue_tail(&local->skb_queue, skb); 2524 tasklet_schedule(&local->tasklet); 2525 } 2526 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2527