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 u16 mpdu_seq_num, 34 int bar_req); 35 /* 36 * monitor mode reception 37 * 38 * This function cleans up the SKB, i.e. it removes all the stuff 39 * only useful for monitoring. 40 */ 41 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local, 42 struct sk_buff *skb, 43 int rtap_len) 44 { 45 skb_pull(skb, rtap_len); 46 47 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) { 48 if (likely(skb->len > FCS_LEN)) 49 skb_trim(skb, skb->len - FCS_LEN); 50 else { 51 /* driver bug */ 52 WARN_ON(1); 53 dev_kfree_skb(skb); 54 skb = NULL; 55 } 56 } 57 58 return skb; 59 } 60 61 static inline int should_drop_frame(struct sk_buff *skb, 62 int present_fcs_len, 63 int radiotap_len) 64 { 65 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 66 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 67 68 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 69 return 1; 70 if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len)) 71 return 1; 72 if (ieee80211_is_ctl(hdr->frame_control) && 73 !ieee80211_is_pspoll(hdr->frame_control) && 74 !ieee80211_is_back_req(hdr->frame_control)) 75 return 1; 76 return 0; 77 } 78 79 static int 80 ieee80211_rx_radiotap_len(struct ieee80211_local *local, 81 struct ieee80211_rx_status *status) 82 { 83 int len; 84 85 /* always present fields */ 86 len = sizeof(struct ieee80211_radiotap_header) + 9; 87 88 if (status->flag & RX_FLAG_TSFT) 89 len += 8; 90 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) 91 len += 1; 92 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) 93 len += 1; 94 95 if (len & 1) /* padding for RX_FLAGS if necessary */ 96 len++; 97 98 /* make sure radiotap starts at a naturally aligned address */ 99 if (len % 8) 100 len = roundup(len, 8); 101 102 return len; 103 } 104 105 /* 106 * ieee80211_add_rx_radiotap_header - add radiotap header 107 * 108 * add a radiotap header containing all the fields which the hardware provided. 109 */ 110 static void 111 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, 112 struct sk_buff *skb, 113 struct ieee80211_rate *rate, 114 int rtap_len) 115 { 116 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 117 struct ieee80211_radiotap_header *rthdr; 118 unsigned char *pos; 119 120 rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); 121 memset(rthdr, 0, rtap_len); 122 123 /* radiotap header, set always present flags */ 124 rthdr->it_present = 125 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 126 (1 << IEEE80211_RADIOTAP_CHANNEL) | 127 (1 << IEEE80211_RADIOTAP_ANTENNA) | 128 (1 << IEEE80211_RADIOTAP_RX_FLAGS)); 129 rthdr->it_len = cpu_to_le16(rtap_len); 130 131 pos = (unsigned char *)(rthdr+1); 132 133 /* the order of the following fields is important */ 134 135 /* IEEE80211_RADIOTAP_TSFT */ 136 if (status->flag & RX_FLAG_TSFT) { 137 *(__le64 *)pos = cpu_to_le64(status->mactime); 138 rthdr->it_present |= 139 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); 140 pos += 8; 141 } 142 143 /* IEEE80211_RADIOTAP_FLAGS */ 144 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 145 *pos |= IEEE80211_RADIOTAP_F_FCS; 146 if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) 147 *pos |= IEEE80211_RADIOTAP_F_BADFCS; 148 if (status->flag & RX_FLAG_SHORTPRE) 149 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE; 150 pos++; 151 152 /* IEEE80211_RADIOTAP_RATE */ 153 if (status->flag & RX_FLAG_HT) { 154 /* 155 * TODO: add following information into radiotap header once 156 * suitable fields are defined for it: 157 * - MCS index (status->rate_idx) 158 * - HT40 (status->flag & RX_FLAG_40MHZ) 159 * - short-GI (status->flag & RX_FLAG_SHORT_GI) 160 */ 161 *pos = 0; 162 } else { 163 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); 164 *pos = rate->bitrate / 5; 165 } 166 pos++; 167 168 /* IEEE80211_RADIOTAP_CHANNEL */ 169 *(__le16 *)pos = cpu_to_le16(status->freq); 170 pos += 2; 171 if (status->band == IEEE80211_BAND_5GHZ) 172 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | 173 IEEE80211_CHAN_5GHZ); 174 else if (rate->flags & IEEE80211_RATE_ERP_G) 175 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | 176 IEEE80211_CHAN_2GHZ); 177 else 178 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK | 179 IEEE80211_CHAN_2GHZ); 180 pos += 2; 181 182 /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ 183 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { 184 *pos = status->signal; 185 rthdr->it_present |= 186 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); 187 pos++; 188 } 189 190 /* IEEE80211_RADIOTAP_DBM_ANTNOISE */ 191 if (local->hw.flags & IEEE80211_HW_NOISE_DBM) { 192 *pos = status->noise; 193 rthdr->it_present |= 194 cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE); 195 pos++; 196 } 197 198 /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ 199 200 /* IEEE80211_RADIOTAP_ANTENNA */ 201 *pos = status->antenna; 202 pos++; 203 204 /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ 205 206 /* IEEE80211_RADIOTAP_RX_FLAGS */ 207 /* ensure 2 byte alignment for the 2 byte field as required */ 208 if ((pos - (unsigned char *)rthdr) & 1) 209 pos++; 210 if (status->flag & RX_FLAG_FAILED_PLCP_CRC) 211 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP); 212 pos += 2; 213 } 214 215 /* 216 * This function copies a received frame to all monitor interfaces and 217 * returns a cleaned-up SKB that no longer includes the FCS nor the 218 * radiotap header the driver might have added. 219 */ 220 static struct sk_buff * 221 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, 222 struct ieee80211_rate *rate) 223 { 224 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb); 225 struct ieee80211_sub_if_data *sdata; 226 int needed_headroom = 0; 227 struct sk_buff *skb, *skb2; 228 struct net_device *prev_dev = NULL; 229 int present_fcs_len = 0; 230 int rtap_len = 0; 231 232 /* 233 * First, we may need to make a copy of the skb because 234 * (1) we need to modify it for radiotap (if not present), and 235 * (2) the other RX handlers will modify the skb we got. 236 * 237 * We don't need to, of course, if we aren't going to return 238 * the SKB because it has a bad FCS/PLCP checksum. 239 */ 240 if (status->flag & RX_FLAG_RADIOTAP) 241 rtap_len = ieee80211_get_radiotap_len(origskb->data); 242 else 243 /* room for the radiotap header based on driver features */ 244 needed_headroom = ieee80211_rx_radiotap_len(local, status); 245 246 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) 247 present_fcs_len = FCS_LEN; 248 249 if (!local->monitors) { 250 if (should_drop_frame(origskb, present_fcs_len, rtap_len)) { 251 dev_kfree_skb(origskb); 252 return NULL; 253 } 254 255 return remove_monitor_info(local, origskb, rtap_len); 256 } 257 258 if (should_drop_frame(origskb, present_fcs_len, rtap_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, rtap_len); 283 284 if (!skb) 285 return origskb; 286 } 287 288 /* if necessary, prepend radiotap information */ 289 if (!(status->flag & RX_FLAG_RADIOTAP)) 290 ieee80211_add_rx_radiotap_header(local, skb, rate, 291 needed_headroom); 292 293 skb_reset_mac_header(skb); 294 skb->ip_summed = CHECKSUM_UNNECESSARY; 295 skb->pkt_type = PACKET_OTHERHOST; 296 skb->protocol = htons(ETH_P_802_2); 297 298 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 299 if (!netif_running(sdata->dev)) 300 continue; 301 302 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) 303 continue; 304 305 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) 306 continue; 307 308 if (prev_dev) { 309 skb2 = skb_clone(skb, GFP_ATOMIC); 310 if (skb2) { 311 skb2->dev = prev_dev; 312 netif_rx(skb2); 313 } 314 } 315 316 prev_dev = sdata->dev; 317 sdata->dev->stats.rx_packets++; 318 sdata->dev->stats.rx_bytes += skb->len; 319 } 320 321 if (prev_dev) { 322 skb->dev = prev_dev; 323 netif_rx(skb); 324 } else 325 dev_kfree_skb(skb); 326 327 return origskb; 328 } 329 330 331 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx) 332 { 333 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 334 int tid; 335 336 /* does the frame have a qos control field? */ 337 if (ieee80211_is_data_qos(hdr->frame_control)) { 338 u8 *qc = ieee80211_get_qos_ctl(hdr); 339 /* frame has qos control */ 340 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 341 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) 342 rx->flags |= IEEE80211_RX_AMSDU; 343 else 344 rx->flags &= ~IEEE80211_RX_AMSDU; 345 } else { 346 /* 347 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"): 348 * 349 * Sequence numbers for management frames, QoS data 350 * frames with a broadcast/multicast address in the 351 * Address 1 field, and all non-QoS data frames sent 352 * by QoS STAs are assigned using an additional single 353 * modulo-4096 counter, [...] 354 * 355 * We also use that counter for non-QoS STAs. 356 */ 357 tid = NUM_RX_DATA_QUEUES - 1; 358 } 359 360 rx->queue = tid; 361 /* Set skb->priority to 1d tag if highest order bit of TID is not set. 362 * For now, set skb->priority to 0 for other cases. */ 363 rx->skb->priority = (tid > 7) ? 0 : tid; 364 } 365 366 /** 367 * DOC: Packet alignment 368 * 369 * Drivers always need to pass packets that are aligned to two-byte boundaries 370 * to the stack. 371 * 372 * Additionally, should, if possible, align the payload data in a way that 373 * guarantees that the contained IP header is aligned to a four-byte 374 * boundary. In the case of regular frames, this simply means aligning the 375 * payload to a four-byte boundary (because either the IP header is directly 376 * contained, or IV/RFC1042 headers that have a length divisible by four are 377 * in front of it). 378 * 379 * With A-MSDU frames, however, the payload data address must yield two modulo 380 * four because there are 14-byte 802.3 headers within the A-MSDU frames that 381 * push the IP header further back to a multiple of four again. Thankfully, the 382 * specs were sane enough this time around to require padding each A-MSDU 383 * subframe to a length that is a multiple of four. 384 * 385 * Padding like Atheros hardware adds which is inbetween the 802.11 header and 386 * the payload is not supported, the driver is required to move the 802.11 387 * header to be directly in front of the payload in that case. 388 */ 389 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx) 390 { 391 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 392 int hdrlen; 393 394 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT 395 return; 396 #endif 397 398 if (WARN_ONCE((unsigned long)rx->skb->data & 1, 399 "unaligned packet at 0x%p\n", rx->skb->data)) 400 return; 401 402 if (!ieee80211_is_data_present(hdr->frame_control)) 403 return; 404 405 hdrlen = ieee80211_hdrlen(hdr->frame_control); 406 if (rx->flags & IEEE80211_RX_AMSDU) 407 hdrlen += ETH_HLEN; 408 WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3, 409 "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen); 410 } 411 412 413 /* rx handlers */ 414 415 static ieee80211_rx_result debug_noinline 416 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx) 417 { 418 struct ieee80211_local *local = rx->local; 419 struct sk_buff *skb = rx->skb; 420 421 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning))) 422 return ieee80211_scan_rx(rx->sdata, skb); 423 424 if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) && 425 (rx->flags & IEEE80211_RX_IN_SCAN))) { 426 /* drop all the other packets during a software scan anyway */ 427 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED) 428 dev_kfree_skb(skb); 429 return RX_QUEUED; 430 } 431 432 if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) { 433 /* scanning finished during invoking of handlers */ 434 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan); 435 return RX_DROP_UNUSABLE; 436 } 437 438 return RX_CONTINUE; 439 } 440 441 442 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb) 443 { 444 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 445 446 if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1)) 447 return 0; 448 449 return ieee80211_is_robust_mgmt_frame(hdr); 450 } 451 452 453 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb) 454 { 455 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 456 457 if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1)) 458 return 0; 459 460 return ieee80211_is_robust_mgmt_frame(hdr); 461 } 462 463 464 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */ 465 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) 466 { 467 struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; 468 struct ieee80211_mmie *mmie; 469 470 if (skb->len < 24 + sizeof(*mmie) || 471 !is_multicast_ether_addr(hdr->da)) 472 return -1; 473 474 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr)) 475 return -1; /* not a robust management frame */ 476 477 mmie = (struct ieee80211_mmie *) 478 (skb->data + skb->len - sizeof(*mmie)); 479 if (mmie->element_id != WLAN_EID_MMIE || 480 mmie->length != sizeof(*mmie) - 2) 481 return -1; 482 483 return le16_to_cpu(mmie->key_id); 484 } 485 486 487 static ieee80211_rx_result 488 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx) 489 { 490 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 491 unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control); 492 char *dev_addr = rx->dev->dev_addr; 493 494 if (ieee80211_is_data(hdr->frame_control)) { 495 if (is_multicast_ether_addr(hdr->addr1)) { 496 if (ieee80211_has_tods(hdr->frame_control) || 497 !ieee80211_has_fromds(hdr->frame_control)) 498 return RX_DROP_MONITOR; 499 if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0) 500 return RX_DROP_MONITOR; 501 } else { 502 if (!ieee80211_has_a4(hdr->frame_control)) 503 return RX_DROP_MONITOR; 504 if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0) 505 return RX_DROP_MONITOR; 506 } 507 } 508 509 /* If there is not an established peer link and this is not a peer link 510 * establisment frame, beacon or probe, drop the frame. 511 */ 512 513 if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) { 514 struct ieee80211_mgmt *mgmt; 515 516 if (!ieee80211_is_mgmt(hdr->frame_control)) 517 return RX_DROP_MONITOR; 518 519 if (ieee80211_is_action(hdr->frame_control)) { 520 mgmt = (struct ieee80211_mgmt *)hdr; 521 if (mgmt->u.action.category != PLINK_CATEGORY) 522 return RX_DROP_MONITOR; 523 return RX_CONTINUE; 524 } 525 526 if (ieee80211_is_probe_req(hdr->frame_control) || 527 ieee80211_is_probe_resp(hdr->frame_control) || 528 ieee80211_is_beacon(hdr->frame_control)) 529 return RX_CONTINUE; 530 531 return RX_DROP_MONITOR; 532 533 } 534 535 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l)) 536 537 if (ieee80211_is_data(hdr->frame_control) && 538 is_multicast_ether_addr(hdr->addr1) && 539 mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata)) 540 return RX_DROP_MONITOR; 541 #undef msh_h_get 542 543 return RX_CONTINUE; 544 } 545 546 547 static ieee80211_rx_result debug_noinline 548 ieee80211_rx_h_check(struct ieee80211_rx_data *rx) 549 { 550 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 551 552 /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */ 553 if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) { 554 if (unlikely(ieee80211_has_retry(hdr->frame_control) && 555 rx->sta->last_seq_ctrl[rx->queue] == 556 hdr->seq_ctrl)) { 557 if (rx->flags & IEEE80211_RX_RA_MATCH) { 558 rx->local->dot11FrameDuplicateCount++; 559 rx->sta->num_duplicates++; 560 } 561 return RX_DROP_MONITOR; 562 } else 563 rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl; 564 } 565 566 if (unlikely(rx->skb->len < 16)) { 567 I802_DEBUG_INC(rx->local->rx_handlers_drop_short); 568 return RX_DROP_MONITOR; 569 } 570 571 /* Drop disallowed frame classes based on STA auth/assoc state; 572 * IEEE 802.11, Chap 5.5. 573 * 574 * mac80211 filters only based on association state, i.e. it drops 575 * Class 3 frames from not associated stations. hostapd sends 576 * deauth/disassoc frames when needed. In addition, hostapd is 577 * responsible for filtering on both auth and assoc states. 578 */ 579 580 if (ieee80211_vif_is_mesh(&rx->sdata->vif)) 581 return ieee80211_rx_mesh_check(rx); 582 583 if (unlikely((ieee80211_is_data(hdr->frame_control) || 584 ieee80211_is_pspoll(hdr->frame_control)) && 585 rx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 586 (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) { 587 if ((!ieee80211_has_fromds(hdr->frame_control) && 588 !ieee80211_has_tods(hdr->frame_control) && 589 ieee80211_is_data(hdr->frame_control)) || 590 !(rx->flags & IEEE80211_RX_RA_MATCH)) { 591 /* Drop IBSS frames and frames for other hosts 592 * silently. */ 593 return RX_DROP_MONITOR; 594 } 595 596 return RX_DROP_MONITOR; 597 } 598 599 return RX_CONTINUE; 600 } 601 602 603 static ieee80211_rx_result debug_noinline 604 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) 605 { 606 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 607 int keyidx; 608 int hdrlen; 609 ieee80211_rx_result result = RX_DROP_UNUSABLE; 610 struct ieee80211_key *stakey = NULL; 611 int mmie_keyidx = -1; 612 613 /* 614 * Key selection 101 615 * 616 * There are four types of keys: 617 * - GTK (group keys) 618 * - IGTK (group keys for management frames) 619 * - PTK (pairwise keys) 620 * - STK (station-to-station pairwise keys) 621 * 622 * When selecting a key, we have to distinguish between multicast 623 * (including broadcast) and unicast frames, the latter can only 624 * use PTKs and STKs while the former always use GTKs and IGTKs. 625 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then 626 * unicast frames can also use key indices like GTKs. Hence, if we 627 * don't have a PTK/STK we check the key index for a WEP key. 628 * 629 * Note that in a regular BSS, multicast frames are sent by the 630 * AP only, associated stations unicast the frame to the AP first 631 * which then multicasts it on their behalf. 632 * 633 * There is also a slight problem in IBSS mode: GTKs are negotiated 634 * with each station, that is something we don't currently handle. 635 * The spec seems to expect that one negotiates the same key with 636 * every station but there's no such requirement; VLANs could be 637 * possible. 638 */ 639 640 /* 641 * No point in finding a key and decrypting if the frame is neither 642 * addressed to us nor a multicast frame. 643 */ 644 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 645 return RX_CONTINUE; 646 647 if (rx->sta) 648 stakey = rcu_dereference(rx->sta->key); 649 650 if (!ieee80211_has_protected(hdr->frame_control)) 651 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb); 652 653 if (!is_multicast_ether_addr(hdr->addr1) && stakey) { 654 rx->key = stakey; 655 /* Skip decryption if the frame is not protected. */ 656 if (!ieee80211_has_protected(hdr->frame_control)) 657 return RX_CONTINUE; 658 } else if (mmie_keyidx >= 0) { 659 /* Broadcast/multicast robust management frame / BIP */ 660 if ((rx->status->flag & RX_FLAG_DECRYPTED) && 661 (rx->status->flag & RX_FLAG_IV_STRIPPED)) 662 return RX_CONTINUE; 663 664 if (mmie_keyidx < NUM_DEFAULT_KEYS || 665 mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) 666 return RX_DROP_MONITOR; /* unexpected BIP keyidx */ 667 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); 668 } else if (!ieee80211_has_protected(hdr->frame_control)) { 669 /* 670 * The frame was not protected, so skip decryption. However, we 671 * need to set rx->key if there is a key that could have been 672 * used so that the frame may be dropped if encryption would 673 * have been expected. 674 */ 675 struct ieee80211_key *key = NULL; 676 if (ieee80211_is_mgmt(hdr->frame_control) && 677 is_multicast_ether_addr(hdr->addr1) && 678 (key = rcu_dereference(rx->sdata->default_mgmt_key))) 679 rx->key = key; 680 else if ((key = rcu_dereference(rx->sdata->default_key))) 681 rx->key = key; 682 return RX_CONTINUE; 683 } else { 684 /* 685 * The device doesn't give us the IV so we won't be 686 * able to look up the key. That's ok though, we 687 * don't need to decrypt the frame, we just won't 688 * be able to keep statistics accurate. 689 * Except for key threshold notifications, should 690 * we somehow allow the driver to tell us which key 691 * the hardware used if this flag is set? 692 */ 693 if ((rx->status->flag & RX_FLAG_DECRYPTED) && 694 (rx->status->flag & RX_FLAG_IV_STRIPPED)) 695 return RX_CONTINUE; 696 697 hdrlen = ieee80211_hdrlen(hdr->frame_control); 698 699 if (rx->skb->len < 8 + hdrlen) 700 return RX_DROP_UNUSABLE; /* TODO: count this? */ 701 702 /* 703 * no need to call ieee80211_wep_get_keyidx, 704 * it verifies a bunch of things we've done already 705 */ 706 keyidx = rx->skb->data[hdrlen + 3] >> 6; 707 708 rx->key = rcu_dereference(rx->sdata->keys[keyidx]); 709 710 /* 711 * RSNA-protected unicast frames should always be sent with 712 * pairwise or station-to-station keys, but for WEP we allow 713 * using a key index as well. 714 */ 715 if (rx->key && rx->key->conf.alg != ALG_WEP && 716 !is_multicast_ether_addr(hdr->addr1)) 717 rx->key = NULL; 718 } 719 720 if (rx->key) { 721 rx->key->tx_rx_count++; 722 /* TODO: add threshold stuff again */ 723 } else { 724 return RX_DROP_MONITOR; 725 } 726 727 /* Check for weak IVs if possible */ 728 if (rx->sta && rx->key->conf.alg == ALG_WEP && 729 ieee80211_is_data(hdr->frame_control) && 730 (!(rx->status->flag & RX_FLAG_IV_STRIPPED) || 731 !(rx->status->flag & RX_FLAG_DECRYPTED)) && 732 ieee80211_wep_is_weak_iv(rx->skb, rx->key)) 733 rx->sta->wep_weak_iv_count++; 734 735 switch (rx->key->conf.alg) { 736 case ALG_WEP: 737 result = ieee80211_crypto_wep_decrypt(rx); 738 break; 739 case ALG_TKIP: 740 result = ieee80211_crypto_tkip_decrypt(rx); 741 break; 742 case ALG_CCMP: 743 result = ieee80211_crypto_ccmp_decrypt(rx); 744 break; 745 case ALG_AES_CMAC: 746 result = ieee80211_crypto_aes_cmac_decrypt(rx); 747 break; 748 } 749 750 /* either the frame has been decrypted or will be dropped */ 751 rx->status->flag |= RX_FLAG_DECRYPTED; 752 753 return result; 754 } 755 756 static ieee80211_rx_result debug_noinline 757 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx) 758 { 759 struct ieee80211_local *local; 760 struct ieee80211_hdr *hdr; 761 struct sk_buff *skb; 762 763 local = rx->local; 764 skb = rx->skb; 765 hdr = (struct ieee80211_hdr *) skb->data; 766 767 if (!local->pspolling) 768 return RX_CONTINUE; 769 770 if (!ieee80211_has_fromds(hdr->frame_control)) 771 /* this is not from AP */ 772 return RX_CONTINUE; 773 774 if (!ieee80211_is_data(hdr->frame_control)) 775 return RX_CONTINUE; 776 777 if (!ieee80211_has_moredata(hdr->frame_control)) { 778 /* AP has no more frames buffered for us */ 779 local->pspolling = false; 780 return RX_CONTINUE; 781 } 782 783 /* more data bit is set, let's request a new frame from the AP */ 784 ieee80211_send_pspoll(local, rx->sdata); 785 786 return RX_CONTINUE; 787 } 788 789 static void ap_sta_ps_start(struct sta_info *sta) 790 { 791 struct ieee80211_sub_if_data *sdata = sta->sdata; 792 struct ieee80211_local *local = sdata->local; 793 794 atomic_inc(&sdata->bss->num_sta_ps); 795 set_sta_flags(sta, WLAN_STA_PS); 796 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta); 797 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 798 printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n", 799 sdata->dev->name, sta->sta.addr, sta->sta.aid); 800 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 801 } 802 803 static int ap_sta_ps_end(struct sta_info *sta) 804 { 805 struct ieee80211_sub_if_data *sdata = sta->sdata; 806 struct ieee80211_local *local = sdata->local; 807 int sent, buffered; 808 809 atomic_dec(&sdata->bss->num_sta_ps); 810 811 clear_sta_flags(sta, WLAN_STA_PS); 812 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta); 813 814 if (!skb_queue_empty(&sta->ps_tx_buf)) 815 sta_info_clear_tim_bit(sta); 816 817 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 818 printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n", 819 sdata->dev->name, sta->sta.addr, sta->sta.aid); 820 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 821 822 /* Send all buffered frames to the station */ 823 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered); 824 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf); 825 sent += buffered; 826 local->total_ps_buffered -= buffered; 827 828 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 829 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 830 "since STA not sleeping anymore\n", sdata->dev->name, 831 sta->sta.addr, sta->sta.aid, sent - buffered, buffered); 832 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 833 834 return sent; 835 } 836 837 static ieee80211_rx_result debug_noinline 838 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) 839 { 840 struct sta_info *sta = rx->sta; 841 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 842 843 if (!sta) 844 return RX_CONTINUE; 845 846 /* 847 * Update last_rx only for IBSS packets which are for the current 848 * BSSID to avoid keeping the current IBSS network alive in cases 849 * where other STAs start using different BSSID. 850 */ 851 if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) { 852 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, 853 NL80211_IFTYPE_ADHOC); 854 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) 855 sta->last_rx = jiffies; 856 } else if (!is_multicast_ether_addr(hdr->addr1)) { 857 /* 858 * Mesh beacons will update last_rx when if they are found to 859 * match the current local configuration when processed. 860 */ 861 sta->last_rx = jiffies; 862 } 863 864 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 865 return RX_CONTINUE; 866 867 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION) 868 ieee80211_sta_rx_notify(rx->sdata, hdr); 869 870 sta->rx_fragments++; 871 sta->rx_bytes += rx->skb->len; 872 sta->last_signal = rx->status->signal; 873 sta->last_qual = rx->status->qual; 874 sta->last_noise = rx->status->noise; 875 876 /* 877 * Change STA power saving mode only at the end of a frame 878 * exchange sequence. 879 */ 880 if (!ieee80211_has_morefrags(hdr->frame_control) && 881 (rx->sdata->vif.type == NL80211_IFTYPE_AP || 882 rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) { 883 if (test_sta_flags(sta, WLAN_STA_PS)) { 884 /* 885 * Ignore doze->wake transitions that are 886 * indicated by non-data frames, the standard 887 * is unclear here, but for example going to 888 * PS mode and then scanning would cause a 889 * doze->wake transition for the probe request, 890 * and that is clearly undesirable. 891 */ 892 if (ieee80211_is_data(hdr->frame_control) && 893 !ieee80211_has_pm(hdr->frame_control)) 894 rx->sent_ps_buffered += ap_sta_ps_end(sta); 895 } else { 896 if (ieee80211_has_pm(hdr->frame_control)) 897 ap_sta_ps_start(sta); 898 } 899 } 900 901 /* Drop data::nullfunc frames silently, since they are used only to 902 * control station power saving mode. */ 903 if (ieee80211_is_nullfunc(hdr->frame_control)) { 904 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc); 905 /* Update counter and free packet here to avoid counting this 906 * as a dropped packed. */ 907 sta->rx_packets++; 908 dev_kfree_skb(rx->skb); 909 return RX_QUEUED; 910 } 911 912 return RX_CONTINUE; 913 } /* ieee80211_rx_h_sta_process */ 914 915 static inline struct ieee80211_fragment_entry * 916 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata, 917 unsigned int frag, unsigned int seq, int rx_queue, 918 struct sk_buff **skb) 919 { 920 struct ieee80211_fragment_entry *entry; 921 int idx; 922 923 idx = sdata->fragment_next; 924 entry = &sdata->fragments[sdata->fragment_next++]; 925 if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX) 926 sdata->fragment_next = 0; 927 928 if (!skb_queue_empty(&entry->skb_list)) { 929 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 930 struct ieee80211_hdr *hdr = 931 (struct ieee80211_hdr *) entry->skb_list.next->data; 932 printk(KERN_DEBUG "%s: RX reassembly removed oldest " 933 "fragment entry (idx=%d age=%lu seq=%d last_frag=%d " 934 "addr1=%pM addr2=%pM\n", 935 sdata->dev->name, idx, 936 jiffies - entry->first_frag_time, entry->seq, 937 entry->last_frag, hdr->addr1, hdr->addr2); 938 #endif 939 __skb_queue_purge(&entry->skb_list); 940 } 941 942 __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */ 943 *skb = NULL; 944 entry->first_frag_time = jiffies; 945 entry->seq = seq; 946 entry->rx_queue = rx_queue; 947 entry->last_frag = frag; 948 entry->ccmp = 0; 949 entry->extra_len = 0; 950 951 return entry; 952 } 953 954 static inline struct ieee80211_fragment_entry * 955 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata, 956 unsigned int frag, unsigned int seq, 957 int rx_queue, struct ieee80211_hdr *hdr) 958 { 959 struct ieee80211_fragment_entry *entry; 960 int i, idx; 961 962 idx = sdata->fragment_next; 963 for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) { 964 struct ieee80211_hdr *f_hdr; 965 966 idx--; 967 if (idx < 0) 968 idx = IEEE80211_FRAGMENT_MAX - 1; 969 970 entry = &sdata->fragments[idx]; 971 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq || 972 entry->rx_queue != rx_queue || 973 entry->last_frag + 1 != frag) 974 continue; 975 976 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data; 977 978 /* 979 * Check ftype and addresses are equal, else check next fragment 980 */ 981 if (((hdr->frame_control ^ f_hdr->frame_control) & 982 cpu_to_le16(IEEE80211_FCTL_FTYPE)) || 983 compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 || 984 compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0) 985 continue; 986 987 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) { 988 __skb_queue_purge(&entry->skb_list); 989 continue; 990 } 991 return entry; 992 } 993 994 return NULL; 995 } 996 997 static ieee80211_rx_result debug_noinline 998 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) 999 { 1000 struct ieee80211_hdr *hdr; 1001 u16 sc; 1002 __le16 fc; 1003 unsigned int frag, seq; 1004 struct ieee80211_fragment_entry *entry; 1005 struct sk_buff *skb; 1006 1007 hdr = (struct ieee80211_hdr *)rx->skb->data; 1008 fc = hdr->frame_control; 1009 sc = le16_to_cpu(hdr->seq_ctrl); 1010 frag = sc & IEEE80211_SCTL_FRAG; 1011 1012 if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || 1013 (rx->skb)->len < 24 || 1014 is_multicast_ether_addr(hdr->addr1))) { 1015 /* not fragmented */ 1016 goto out; 1017 } 1018 I802_DEBUG_INC(rx->local->rx_handlers_fragments); 1019 1020 seq = (sc & IEEE80211_SCTL_SEQ) >> 4; 1021 1022 if (frag == 0) { 1023 /* This is the first fragment of a new frame. */ 1024 entry = ieee80211_reassemble_add(rx->sdata, frag, seq, 1025 rx->queue, &(rx->skb)); 1026 if (rx->key && rx->key->conf.alg == ALG_CCMP && 1027 ieee80211_has_protected(fc)) { 1028 /* Store CCMP PN so that we can verify that the next 1029 * fragment has a sequential PN value. */ 1030 entry->ccmp = 1; 1031 memcpy(entry->last_pn, 1032 rx->key->u.ccmp.rx_pn[rx->queue], 1033 CCMP_PN_LEN); 1034 } 1035 return RX_QUEUED; 1036 } 1037 1038 /* This is a fragment for a frame that should already be pending in 1039 * fragment cache. Add this fragment to the end of the pending entry. 1040 */ 1041 entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr); 1042 if (!entry) { 1043 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1044 return RX_DROP_MONITOR; 1045 } 1046 1047 /* Verify that MPDUs within one MSDU have sequential PN values. 1048 * (IEEE 802.11i, 8.3.3.4.5) */ 1049 if (entry->ccmp) { 1050 int i; 1051 u8 pn[CCMP_PN_LEN], *rpn; 1052 if (!rx->key || rx->key->conf.alg != ALG_CCMP) 1053 return RX_DROP_UNUSABLE; 1054 memcpy(pn, entry->last_pn, CCMP_PN_LEN); 1055 for (i = CCMP_PN_LEN - 1; i >= 0; i--) { 1056 pn[i]++; 1057 if (pn[i]) 1058 break; 1059 } 1060 rpn = rx->key->u.ccmp.rx_pn[rx->queue]; 1061 if (memcmp(pn, rpn, CCMP_PN_LEN)) 1062 return RX_DROP_UNUSABLE; 1063 memcpy(entry->last_pn, pn, CCMP_PN_LEN); 1064 } 1065 1066 skb_pull(rx->skb, ieee80211_hdrlen(fc)); 1067 __skb_queue_tail(&entry->skb_list, rx->skb); 1068 entry->last_frag = frag; 1069 entry->extra_len += rx->skb->len; 1070 if (ieee80211_has_morefrags(fc)) { 1071 rx->skb = NULL; 1072 return RX_QUEUED; 1073 } 1074 1075 rx->skb = __skb_dequeue(&entry->skb_list); 1076 if (skb_tailroom(rx->skb) < entry->extra_len) { 1077 I802_DEBUG_INC(rx->local->rx_expand_skb_head2); 1078 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len, 1079 GFP_ATOMIC))) { 1080 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag); 1081 __skb_queue_purge(&entry->skb_list); 1082 return RX_DROP_UNUSABLE; 1083 } 1084 } 1085 while ((skb = __skb_dequeue(&entry->skb_list))) { 1086 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len); 1087 dev_kfree_skb(skb); 1088 } 1089 1090 /* Complete frame has been reassembled - process it now */ 1091 rx->flags |= IEEE80211_RX_FRAGMENTED; 1092 1093 out: 1094 if (rx->sta) 1095 rx->sta->rx_packets++; 1096 if (is_multicast_ether_addr(hdr->addr1)) 1097 rx->local->dot11MulticastReceivedFrameCount++; 1098 else 1099 ieee80211_led_rx(rx->local); 1100 return RX_CONTINUE; 1101 } 1102 1103 static ieee80211_rx_result debug_noinline 1104 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx) 1105 { 1106 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1107 struct sk_buff *skb; 1108 int no_pending_pkts; 1109 __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control; 1110 1111 if (likely(!rx->sta || !ieee80211_is_pspoll(fc) || 1112 !(rx->flags & IEEE80211_RX_RA_MATCH))) 1113 return RX_CONTINUE; 1114 1115 if ((sdata->vif.type != NL80211_IFTYPE_AP) && 1116 (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)) 1117 return RX_DROP_UNUSABLE; 1118 1119 skb = skb_dequeue(&rx->sta->tx_filtered); 1120 if (!skb) { 1121 skb = skb_dequeue(&rx->sta->ps_tx_buf); 1122 if (skb) 1123 rx->local->total_ps_buffered--; 1124 } 1125 no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) && 1126 skb_queue_empty(&rx->sta->ps_tx_buf); 1127 1128 if (skb) { 1129 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1130 struct ieee80211_hdr *hdr = 1131 (struct ieee80211_hdr *) skb->data; 1132 1133 /* 1134 * Tell TX path to send this frame even though the STA may 1135 * still remain is PS mode after this frame exchange. 1136 */ 1137 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE; 1138 1139 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1140 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n", 1141 rx->sta->sta.addr, rx->sta->sta.aid, 1142 skb_queue_len(&rx->sta->ps_tx_buf)); 1143 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1144 1145 /* Use MoreData flag to indicate whether there are more 1146 * buffered frames for this STA */ 1147 if (no_pending_pkts) 1148 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 1149 else 1150 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 1151 1152 ieee80211_add_pending_skb(rx->local, skb); 1153 1154 if (no_pending_pkts) 1155 sta_info_clear_tim_bit(rx->sta); 1156 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1157 } else if (!rx->sent_ps_buffered) { 1158 /* 1159 * FIXME: This can be the result of a race condition between 1160 * us expiring a frame and the station polling for it. 1161 * Should we send it a null-func frame indicating we 1162 * have nothing buffered for it? 1163 */ 1164 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 1165 "though there are no buffered frames for it\n", 1166 rx->dev->name, rx->sta->sta.addr); 1167 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1168 } 1169 1170 /* Free PS Poll skb here instead of returning RX_DROP that would 1171 * count as an dropped frame. */ 1172 dev_kfree_skb(rx->skb); 1173 1174 return RX_QUEUED; 1175 } 1176 1177 static ieee80211_rx_result debug_noinline 1178 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx) 1179 { 1180 u8 *data = rx->skb->data; 1181 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data; 1182 1183 if (!ieee80211_is_data_qos(hdr->frame_control)) 1184 return RX_CONTINUE; 1185 1186 /* remove the qos control field, update frame type and meta-data */ 1187 memmove(data + IEEE80211_QOS_CTL_LEN, data, 1188 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN); 1189 hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN); 1190 /* change frame type to non QOS */ 1191 hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1192 1193 return RX_CONTINUE; 1194 } 1195 1196 static int 1197 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx) 1198 { 1199 if (unlikely(!rx->sta || 1200 !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) 1201 return -EACCES; 1202 1203 return 0; 1204 } 1205 1206 static int 1207 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc) 1208 { 1209 /* 1210 * Pass through unencrypted frames if the hardware has 1211 * decrypted them already. 1212 */ 1213 if (rx->status->flag & RX_FLAG_DECRYPTED) 1214 return 0; 1215 1216 /* Drop unencrypted frames if key is set. */ 1217 if (unlikely(!ieee80211_has_protected(fc) && 1218 !ieee80211_is_nullfunc(fc) && 1219 ieee80211_is_data(fc) && 1220 (rx->key || rx->sdata->drop_unencrypted))) 1221 return -EACCES; 1222 if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) { 1223 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) && 1224 rx->key)) 1225 return -EACCES; 1226 /* BIP does not use Protected field, so need to check MMIE */ 1227 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) 1228 && ieee80211_get_mmie_keyidx(rx->skb) < 0 && 1229 rx->key)) 1230 return -EACCES; 1231 /* 1232 * When using MFP, Action frames are not allowed prior to 1233 * having configured keys. 1234 */ 1235 if (unlikely(ieee80211_is_action(fc) && !rx->key && 1236 ieee80211_is_robust_mgmt_frame( 1237 (struct ieee80211_hdr *) rx->skb->data))) 1238 return -EACCES; 1239 } 1240 1241 return 0; 1242 } 1243 1244 static int 1245 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx) 1246 { 1247 struct net_device *dev = rx->dev; 1248 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1249 1250 return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type); 1251 } 1252 1253 /* 1254 * requires that rx->skb is a frame with ethernet header 1255 */ 1256 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc) 1257 { 1258 static const u8 pae_group_addr[ETH_ALEN] __aligned(2) 1259 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 }; 1260 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1261 1262 /* 1263 * Allow EAPOL frames to us/the PAE group address regardless 1264 * of whether the frame was encrypted or not. 1265 */ 1266 if (ehdr->h_proto == htons(ETH_P_PAE) && 1267 (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 || 1268 compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0)) 1269 return true; 1270 1271 if (ieee80211_802_1x_port_control(rx) || 1272 ieee80211_drop_unencrypted(rx, fc)) 1273 return false; 1274 1275 return true; 1276 } 1277 1278 /* 1279 * requires that rx->skb is a frame with ethernet header 1280 */ 1281 static void 1282 ieee80211_deliver_skb(struct ieee80211_rx_data *rx) 1283 { 1284 struct net_device *dev = rx->dev; 1285 struct ieee80211_local *local = rx->local; 1286 struct sk_buff *skb, *xmit_skb; 1287 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1288 struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; 1289 struct sta_info *dsta; 1290 1291 skb = rx->skb; 1292 xmit_skb = NULL; 1293 1294 if ((sdata->vif.type == NL80211_IFTYPE_AP || 1295 sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && 1296 !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && 1297 (rx->flags & IEEE80211_RX_RA_MATCH)) { 1298 if (is_multicast_ether_addr(ehdr->h_dest)) { 1299 /* 1300 * send multicast frames both to higher layers in 1301 * local net stack and back to the wireless medium 1302 */ 1303 xmit_skb = skb_copy(skb, GFP_ATOMIC); 1304 if (!xmit_skb && net_ratelimit()) 1305 printk(KERN_DEBUG "%s: failed to clone " 1306 "multicast frame\n", dev->name); 1307 } else { 1308 dsta = sta_info_get(local, skb->data); 1309 if (dsta && dsta->sdata->dev == dev) { 1310 /* 1311 * The destination station is associated to 1312 * this AP (in this VLAN), so send the frame 1313 * directly to it and do not pass it to local 1314 * net stack. 1315 */ 1316 xmit_skb = skb; 1317 skb = NULL; 1318 } 1319 } 1320 } 1321 1322 if (skb) { 1323 int align __maybe_unused; 1324 1325 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) 1326 /* 1327 * 'align' will only take the values 0 or 2 here 1328 * since all frames are required to be aligned 1329 * to 2-byte boundaries when being passed to 1330 * mac80211. That also explains the __skb_push() 1331 * below. 1332 */ 1333 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3; 1334 if (align) { 1335 if (WARN_ON(skb_headroom(skb) < 3)) { 1336 dev_kfree_skb(skb); 1337 skb = NULL; 1338 } else { 1339 u8 *data = skb->data; 1340 size_t len = skb->len; 1341 u8 *new = __skb_push(skb, align); 1342 memmove(new, data, len); 1343 __skb_trim(skb, len); 1344 } 1345 } 1346 #endif 1347 1348 if (skb) { 1349 /* deliver to local stack */ 1350 skb->protocol = eth_type_trans(skb, dev); 1351 memset(skb->cb, 0, sizeof(skb->cb)); 1352 netif_rx(skb); 1353 } 1354 } 1355 1356 if (xmit_skb) { 1357 /* send to wireless media */ 1358 xmit_skb->protocol = htons(ETH_P_802_3); 1359 skb_reset_network_header(xmit_skb); 1360 skb_reset_mac_header(xmit_skb); 1361 dev_queue_xmit(xmit_skb); 1362 } 1363 } 1364 1365 static ieee80211_rx_result debug_noinline 1366 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) 1367 { 1368 struct net_device *dev = rx->dev; 1369 struct ieee80211_local *local = rx->local; 1370 u16 ethertype; 1371 u8 *payload; 1372 struct sk_buff *skb = rx->skb, *frame = NULL; 1373 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1374 __le16 fc = hdr->frame_control; 1375 const struct ethhdr *eth; 1376 int remaining, err; 1377 u8 dst[ETH_ALEN]; 1378 u8 src[ETH_ALEN]; 1379 1380 if (unlikely(!ieee80211_is_data(fc))) 1381 return RX_CONTINUE; 1382 1383 if (unlikely(!ieee80211_is_data_present(fc))) 1384 return RX_DROP_MONITOR; 1385 1386 if (!(rx->flags & IEEE80211_RX_AMSDU)) 1387 return RX_CONTINUE; 1388 1389 err = __ieee80211_data_to_8023(rx); 1390 if (unlikely(err)) 1391 return RX_DROP_UNUSABLE; 1392 1393 skb->dev = dev; 1394 1395 dev->stats.rx_packets++; 1396 dev->stats.rx_bytes += skb->len; 1397 1398 /* skip the wrapping header */ 1399 eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr)); 1400 if (!eth) 1401 return RX_DROP_UNUSABLE; 1402 1403 while (skb != frame) { 1404 u8 padding; 1405 __be16 len = eth->h_proto; 1406 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len); 1407 1408 remaining = skb->len; 1409 memcpy(dst, eth->h_dest, ETH_ALEN); 1410 memcpy(src, eth->h_source, ETH_ALEN); 1411 1412 padding = ((4 - subframe_len) & 0x3); 1413 /* the last MSDU has no padding */ 1414 if (subframe_len > remaining) 1415 return RX_DROP_UNUSABLE; 1416 1417 skb_pull(skb, sizeof(struct ethhdr)); 1418 /* if last subframe reuse skb */ 1419 if (remaining <= subframe_len + padding) 1420 frame = skb; 1421 else { 1422 /* 1423 * Allocate and reserve two bytes more for payload 1424 * alignment since sizeof(struct ethhdr) is 14. 1425 */ 1426 frame = dev_alloc_skb( 1427 ALIGN(local->hw.extra_tx_headroom, 4) + 1428 subframe_len + 2); 1429 1430 if (frame == NULL) 1431 return RX_DROP_UNUSABLE; 1432 1433 skb_reserve(frame, 1434 ALIGN(local->hw.extra_tx_headroom, 4) + 1435 sizeof(struct ethhdr) + 2); 1436 memcpy(skb_put(frame, ntohs(len)), skb->data, 1437 ntohs(len)); 1438 1439 eth = (struct ethhdr *) skb_pull(skb, ntohs(len) + 1440 padding); 1441 if (!eth) { 1442 dev_kfree_skb(frame); 1443 return RX_DROP_UNUSABLE; 1444 } 1445 } 1446 1447 skb_reset_network_header(frame); 1448 frame->dev = dev; 1449 frame->priority = skb->priority; 1450 rx->skb = frame; 1451 1452 payload = frame->data; 1453 ethertype = (payload[6] << 8) | payload[7]; 1454 1455 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && 1456 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || 1457 compare_ether_addr(payload, 1458 bridge_tunnel_header) == 0)) { 1459 /* remove RFC1042 or Bridge-Tunnel 1460 * encapsulation and replace EtherType */ 1461 skb_pull(frame, 6); 1462 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1463 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1464 } else { 1465 memcpy(skb_push(frame, sizeof(__be16)), 1466 &len, sizeof(__be16)); 1467 memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN); 1468 memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN); 1469 } 1470 1471 if (!ieee80211_frame_allowed(rx, fc)) { 1472 if (skb == frame) /* last frame */ 1473 return RX_DROP_UNUSABLE; 1474 dev_kfree_skb(frame); 1475 continue; 1476 } 1477 1478 ieee80211_deliver_skb(rx); 1479 } 1480 1481 return RX_QUEUED; 1482 } 1483 1484 #ifdef CONFIG_MAC80211_MESH 1485 static ieee80211_rx_result 1486 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 1487 { 1488 struct ieee80211_hdr *hdr; 1489 struct ieee80211s_hdr *mesh_hdr; 1490 unsigned int hdrlen; 1491 struct sk_buff *skb = rx->skb, *fwd_skb; 1492 struct ieee80211_local *local = rx->local; 1493 struct ieee80211_sub_if_data *sdata; 1494 1495 hdr = (struct ieee80211_hdr *) skb->data; 1496 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1497 mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); 1498 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1499 1500 if (!ieee80211_is_data(hdr->frame_control)) 1501 return RX_CONTINUE; 1502 1503 if (!mesh_hdr->ttl) 1504 /* illegal frame */ 1505 return RX_DROP_MONITOR; 1506 1507 if (!is_multicast_ether_addr(hdr->addr1) && 1508 (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6)) { 1509 struct mesh_path *mppath; 1510 1511 rcu_read_lock(); 1512 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata); 1513 if (!mppath) { 1514 mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata); 1515 } else { 1516 spin_lock_bh(&mppath->state_lock); 1517 mppath->exp_time = jiffies; 1518 if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0) 1519 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN); 1520 spin_unlock_bh(&mppath->state_lock); 1521 } 1522 rcu_read_unlock(); 1523 } 1524 1525 /* Frame has reached destination. Don't forward */ 1526 if (!is_multicast_ether_addr(hdr->addr1) && 1527 compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0) 1528 return RX_CONTINUE; 1529 1530 mesh_hdr->ttl--; 1531 1532 if (rx->flags & IEEE80211_RX_RA_MATCH) { 1533 if (!mesh_hdr->ttl) 1534 IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh, 1535 dropped_frames_ttl); 1536 else { 1537 struct ieee80211_hdr *fwd_hdr; 1538 struct ieee80211_tx_info *info; 1539 1540 fwd_skb = skb_copy(skb, GFP_ATOMIC); 1541 1542 if (!fwd_skb && net_ratelimit()) 1543 printk(KERN_DEBUG "%s: failed to clone mesh frame\n", 1544 rx->dev->name); 1545 1546 fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data; 1547 memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN); 1548 info = IEEE80211_SKB_CB(fwd_skb); 1549 memset(info, 0, sizeof(*info)); 1550 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1551 info->control.vif = &rx->sdata->vif; 1552 ieee80211_select_queue(local, fwd_skb); 1553 if (is_multicast_ether_addr(fwd_hdr->addr1)) 1554 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1555 fwded_mcast); 1556 else { 1557 int err; 1558 /* 1559 * Save TA to addr1 to send TA a path error if a 1560 * suitable next hop is not found 1561 */ 1562 memcpy(fwd_hdr->addr1, fwd_hdr->addr2, 1563 ETH_ALEN); 1564 err = mesh_nexthop_lookup(fwd_skb, sdata); 1565 /* Failed to immediately resolve next hop: 1566 * fwded frame was dropped or will be added 1567 * later to the pending skb queue. */ 1568 if (err) 1569 return RX_DROP_MONITOR; 1570 1571 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1572 fwded_unicast); 1573 } 1574 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh, 1575 fwded_frames); 1576 ieee80211_add_pending_skb(local, fwd_skb); 1577 } 1578 } 1579 1580 if (is_multicast_ether_addr(hdr->addr1) || 1581 rx->dev->flags & IFF_PROMISC) 1582 return RX_CONTINUE; 1583 else 1584 return RX_DROP_MONITOR; 1585 } 1586 #endif 1587 1588 static ieee80211_rx_result debug_noinline 1589 ieee80211_rx_h_data(struct ieee80211_rx_data *rx) 1590 { 1591 struct net_device *dev = rx->dev; 1592 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 1593 __le16 fc = hdr->frame_control; 1594 int err; 1595 1596 if (unlikely(!ieee80211_is_data(hdr->frame_control))) 1597 return RX_CONTINUE; 1598 1599 if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) 1600 return RX_DROP_MONITOR; 1601 1602 err = __ieee80211_data_to_8023(rx); 1603 if (unlikely(err)) 1604 return RX_DROP_UNUSABLE; 1605 1606 if (!ieee80211_frame_allowed(rx, fc)) 1607 return RX_DROP_MONITOR; 1608 1609 rx->skb->dev = dev; 1610 1611 dev->stats.rx_packets++; 1612 dev->stats.rx_bytes += rx->skb->len; 1613 1614 ieee80211_deliver_skb(rx); 1615 1616 return RX_QUEUED; 1617 } 1618 1619 static ieee80211_rx_result debug_noinline 1620 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx) 1621 { 1622 struct ieee80211_local *local = rx->local; 1623 struct ieee80211_hw *hw = &local->hw; 1624 struct sk_buff *skb = rx->skb; 1625 struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data; 1626 struct tid_ampdu_rx *tid_agg_rx; 1627 u16 start_seq_num; 1628 u16 tid; 1629 1630 if (likely(!ieee80211_is_ctl(bar->frame_control))) 1631 return RX_CONTINUE; 1632 1633 if (ieee80211_is_back_req(bar->frame_control)) { 1634 if (!rx->sta) 1635 return RX_CONTINUE; 1636 tid = le16_to_cpu(bar->control) >> 12; 1637 if (rx->sta->ampdu_mlme.tid_state_rx[tid] 1638 != HT_AGG_STATE_OPERATIONAL) 1639 return RX_CONTINUE; 1640 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid]; 1641 1642 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4; 1643 1644 /* reset session timer */ 1645 if (tid_agg_rx->timeout) 1646 mod_timer(&tid_agg_rx->session_timer, 1647 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 1648 1649 /* manage reordering buffer according to requested */ 1650 /* sequence number */ 1651 rcu_read_lock(); 1652 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, 1653 start_seq_num, 1); 1654 rcu_read_unlock(); 1655 return RX_DROP_UNUSABLE; 1656 } 1657 1658 return RX_CONTINUE; 1659 } 1660 1661 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata, 1662 struct ieee80211_mgmt *mgmt, 1663 size_t len) 1664 { 1665 struct ieee80211_local *local = sdata->local; 1666 struct sk_buff *skb; 1667 struct ieee80211_mgmt *resp; 1668 1669 if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) { 1670 /* Not to own unicast address */ 1671 return; 1672 } 1673 1674 if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 || 1675 compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) { 1676 /* Not from the current AP or not associated yet. */ 1677 return; 1678 } 1679 1680 if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) { 1681 /* Too short SA Query request frame */ 1682 return; 1683 } 1684 1685 skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom); 1686 if (skb == NULL) 1687 return; 1688 1689 skb_reserve(skb, local->hw.extra_tx_headroom); 1690 resp = (struct ieee80211_mgmt *) skb_put(skb, 24); 1691 memset(resp, 0, 24); 1692 memcpy(resp->da, mgmt->sa, ETH_ALEN); 1693 memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN); 1694 memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN); 1695 resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 1696 IEEE80211_STYPE_ACTION); 1697 skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query)); 1698 resp->u.action.category = WLAN_CATEGORY_SA_QUERY; 1699 resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE; 1700 memcpy(resp->u.action.u.sa_query.trans_id, 1701 mgmt->u.action.u.sa_query.trans_id, 1702 WLAN_SA_QUERY_TR_ID_LEN); 1703 1704 ieee80211_tx_skb(sdata, skb, 1); 1705 } 1706 1707 static ieee80211_rx_result debug_noinline 1708 ieee80211_rx_h_action(struct ieee80211_rx_data *rx) 1709 { 1710 struct ieee80211_local *local = rx->local; 1711 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1712 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1713 int len = rx->skb->len; 1714 1715 if (!ieee80211_is_action(mgmt->frame_control)) 1716 return RX_CONTINUE; 1717 1718 if (!rx->sta) 1719 return RX_DROP_MONITOR; 1720 1721 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1722 return RX_DROP_MONITOR; 1723 1724 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1725 return RX_DROP_MONITOR; 1726 1727 /* all categories we currently handle have action_code */ 1728 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 1729 return RX_DROP_MONITOR; 1730 1731 switch (mgmt->u.action.category) { 1732 case WLAN_CATEGORY_BACK: 1733 /* 1734 * The aggregation code is not prepared to handle 1735 * anything but STA/AP due to the BSSID handling; 1736 * IBSS could work in the code but isn't supported 1737 * by drivers or the standard. 1738 */ 1739 if (sdata->vif.type != NL80211_IFTYPE_STATION && 1740 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 1741 sdata->vif.type != NL80211_IFTYPE_AP) 1742 return RX_DROP_MONITOR; 1743 1744 switch (mgmt->u.action.u.addba_req.action_code) { 1745 case WLAN_ACTION_ADDBA_REQ: 1746 if (len < (IEEE80211_MIN_ACTION_SIZE + 1747 sizeof(mgmt->u.action.u.addba_req))) 1748 return RX_DROP_MONITOR; 1749 ieee80211_process_addba_request(local, rx->sta, mgmt, len); 1750 break; 1751 case WLAN_ACTION_ADDBA_RESP: 1752 if (len < (IEEE80211_MIN_ACTION_SIZE + 1753 sizeof(mgmt->u.action.u.addba_resp))) 1754 return RX_DROP_MONITOR; 1755 ieee80211_process_addba_resp(local, rx->sta, mgmt, len); 1756 break; 1757 case WLAN_ACTION_DELBA: 1758 if (len < (IEEE80211_MIN_ACTION_SIZE + 1759 sizeof(mgmt->u.action.u.delba))) 1760 return RX_DROP_MONITOR; 1761 ieee80211_process_delba(sdata, rx->sta, mgmt, len); 1762 break; 1763 } 1764 break; 1765 case WLAN_CATEGORY_SPECTRUM_MGMT: 1766 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ) 1767 return RX_DROP_MONITOR; 1768 1769 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1770 return RX_DROP_MONITOR; 1771 1772 switch (mgmt->u.action.u.measurement.action_code) { 1773 case WLAN_ACTION_SPCT_MSR_REQ: 1774 if (len < (IEEE80211_MIN_ACTION_SIZE + 1775 sizeof(mgmt->u.action.u.measurement))) 1776 return RX_DROP_MONITOR; 1777 ieee80211_process_measurement_req(sdata, mgmt, len); 1778 break; 1779 case WLAN_ACTION_SPCT_CHL_SWITCH: 1780 if (len < (IEEE80211_MIN_ACTION_SIZE + 1781 sizeof(mgmt->u.action.u.chan_switch))) 1782 return RX_DROP_MONITOR; 1783 1784 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1785 return RX_DROP_MONITOR; 1786 1787 if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN)) 1788 return RX_DROP_MONITOR; 1789 1790 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 1791 } 1792 break; 1793 case WLAN_CATEGORY_SA_QUERY: 1794 if (len < (IEEE80211_MIN_ACTION_SIZE + 1795 sizeof(mgmt->u.action.u.sa_query))) 1796 return RX_DROP_MONITOR; 1797 switch (mgmt->u.action.u.sa_query.action) { 1798 case WLAN_ACTION_SA_QUERY_REQUEST: 1799 if (sdata->vif.type != NL80211_IFTYPE_STATION) 1800 return RX_DROP_MONITOR; 1801 ieee80211_process_sa_query_req(sdata, mgmt, len); 1802 break; 1803 case WLAN_ACTION_SA_QUERY_RESPONSE: 1804 /* 1805 * SA Query response is currently only used in AP mode 1806 * and it is processed in user space. 1807 */ 1808 return RX_CONTINUE; 1809 } 1810 break; 1811 default: 1812 return RX_CONTINUE; 1813 } 1814 1815 rx->sta->rx_packets++; 1816 dev_kfree_skb(rx->skb); 1817 return RX_QUEUED; 1818 } 1819 1820 static ieee80211_rx_result debug_noinline 1821 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) 1822 { 1823 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev); 1824 struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data; 1825 1826 if (!(rx->flags & IEEE80211_RX_RA_MATCH)) 1827 return RX_DROP_MONITOR; 1828 1829 if (ieee80211_drop_unencrypted(rx, mgmt->frame_control)) 1830 return RX_DROP_MONITOR; 1831 1832 if (ieee80211_vif_is_mesh(&sdata->vif)) 1833 return ieee80211_mesh_rx_mgmt(sdata, rx->skb); 1834 1835 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 1836 return ieee80211_ibss_rx_mgmt(sdata, rx->skb); 1837 1838 if (sdata->vif.type == NL80211_IFTYPE_STATION) 1839 return ieee80211_sta_rx_mgmt(sdata, rx->skb); 1840 1841 return RX_DROP_MONITOR; 1842 } 1843 1844 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, 1845 struct ieee80211_rx_data *rx) 1846 { 1847 int keyidx; 1848 unsigned int hdrlen; 1849 1850 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1851 if (rx->skb->len >= hdrlen + 4) 1852 keyidx = rx->skb->data[hdrlen + 3] >> 6; 1853 else 1854 keyidx = -1; 1855 1856 if (!rx->sta) { 1857 /* 1858 * Some hardware seem to generate incorrect Michael MIC 1859 * reports; ignore them to avoid triggering countermeasures. 1860 */ 1861 goto ignore; 1862 } 1863 1864 if (!ieee80211_has_protected(hdr->frame_control)) 1865 goto ignore; 1866 1867 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) { 1868 /* 1869 * APs with pairwise keys should never receive Michael MIC 1870 * errors for non-zero keyidx because these are reserved for 1871 * group keys and only the AP is sending real multicast 1872 * frames in the BSS. 1873 */ 1874 goto ignore; 1875 } 1876 1877 if (!ieee80211_is_data(hdr->frame_control) && 1878 !ieee80211_is_auth(hdr->frame_control)) 1879 goto ignore; 1880 1881 mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, 1882 GFP_ATOMIC); 1883 ignore: 1884 dev_kfree_skb(rx->skb); 1885 rx->skb = NULL; 1886 } 1887 1888 /* TODO: use IEEE80211_RX_FRAGMENTED */ 1889 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx) 1890 { 1891 struct ieee80211_sub_if_data *sdata; 1892 struct ieee80211_local *local = rx->local; 1893 struct ieee80211_rtap_hdr { 1894 struct ieee80211_radiotap_header hdr; 1895 u8 flags; 1896 u8 rate; 1897 __le16 chan_freq; 1898 __le16 chan_flags; 1899 } __attribute__ ((packed)) *rthdr; 1900 struct sk_buff *skb = rx->skb, *skb2; 1901 struct net_device *prev_dev = NULL; 1902 struct ieee80211_rx_status *status = rx->status; 1903 1904 if (rx->flags & IEEE80211_RX_CMNTR_REPORTED) 1905 goto out_free_skb; 1906 1907 if (skb_headroom(skb) < sizeof(*rthdr) && 1908 pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) 1909 goto out_free_skb; 1910 1911 rthdr = (void *)skb_push(skb, sizeof(*rthdr)); 1912 memset(rthdr, 0, sizeof(*rthdr)); 1913 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr)); 1914 rthdr->hdr.it_present = 1915 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | 1916 (1 << IEEE80211_RADIOTAP_RATE) | 1917 (1 << IEEE80211_RADIOTAP_CHANNEL)); 1918 1919 rthdr->rate = rx->rate->bitrate / 5; 1920 rthdr->chan_freq = cpu_to_le16(status->freq); 1921 1922 if (status->band == IEEE80211_BAND_5GHZ) 1923 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM | 1924 IEEE80211_CHAN_5GHZ); 1925 else 1926 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN | 1927 IEEE80211_CHAN_2GHZ); 1928 1929 skb_set_mac_header(skb, 0); 1930 skb->ip_summed = CHECKSUM_UNNECESSARY; 1931 skb->pkt_type = PACKET_OTHERHOST; 1932 skb->protocol = htons(ETH_P_802_2); 1933 1934 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 1935 if (!netif_running(sdata->dev)) 1936 continue; 1937 1938 if (sdata->vif.type != NL80211_IFTYPE_MONITOR || 1939 !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)) 1940 continue; 1941 1942 if (prev_dev) { 1943 skb2 = skb_clone(skb, GFP_ATOMIC); 1944 if (skb2) { 1945 skb2->dev = prev_dev; 1946 netif_rx(skb2); 1947 } 1948 } 1949 1950 prev_dev = sdata->dev; 1951 sdata->dev->stats.rx_packets++; 1952 sdata->dev->stats.rx_bytes += skb->len; 1953 } 1954 1955 if (prev_dev) { 1956 skb->dev = prev_dev; 1957 netif_rx(skb); 1958 skb = NULL; 1959 } else 1960 goto out_free_skb; 1961 1962 rx->flags |= IEEE80211_RX_CMNTR_REPORTED; 1963 return; 1964 1965 out_free_skb: 1966 dev_kfree_skb(skb); 1967 } 1968 1969 1970 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata, 1971 struct ieee80211_rx_data *rx, 1972 struct sk_buff *skb) 1973 { 1974 ieee80211_rx_result res = RX_DROP_MONITOR; 1975 1976 rx->skb = skb; 1977 rx->sdata = sdata; 1978 rx->dev = sdata->dev; 1979 1980 #define CALL_RXH(rxh) \ 1981 do { \ 1982 res = rxh(rx); \ 1983 if (res != RX_CONTINUE) \ 1984 goto rxh_done; \ 1985 } while (0); 1986 1987 CALL_RXH(ieee80211_rx_h_passive_scan) 1988 CALL_RXH(ieee80211_rx_h_check) 1989 CALL_RXH(ieee80211_rx_h_decrypt) 1990 CALL_RXH(ieee80211_rx_h_check_more_data) 1991 CALL_RXH(ieee80211_rx_h_sta_process) 1992 CALL_RXH(ieee80211_rx_h_defragment) 1993 CALL_RXH(ieee80211_rx_h_ps_poll) 1994 CALL_RXH(ieee80211_rx_h_michael_mic_verify) 1995 /* must be after MMIC verify so header is counted in MPDU mic */ 1996 CALL_RXH(ieee80211_rx_h_remove_qos_control) 1997 CALL_RXH(ieee80211_rx_h_amsdu) 1998 #ifdef CONFIG_MAC80211_MESH 1999 if (ieee80211_vif_is_mesh(&sdata->vif)) 2000 CALL_RXH(ieee80211_rx_h_mesh_fwding); 2001 #endif 2002 CALL_RXH(ieee80211_rx_h_data) 2003 CALL_RXH(ieee80211_rx_h_ctrl) 2004 CALL_RXH(ieee80211_rx_h_action) 2005 CALL_RXH(ieee80211_rx_h_mgmt) 2006 2007 #undef CALL_RXH 2008 2009 rxh_done: 2010 switch (res) { 2011 case RX_DROP_MONITOR: 2012 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2013 if (rx->sta) 2014 rx->sta->rx_dropped++; 2015 /* fall through */ 2016 case RX_CONTINUE: 2017 ieee80211_rx_cooked_monitor(rx); 2018 break; 2019 case RX_DROP_UNUSABLE: 2020 I802_DEBUG_INC(sdata->local->rx_handlers_drop); 2021 if (rx->sta) 2022 rx->sta->rx_dropped++; 2023 dev_kfree_skb(rx->skb); 2024 break; 2025 case RX_QUEUED: 2026 I802_DEBUG_INC(sdata->local->rx_handlers_queued); 2027 break; 2028 } 2029 } 2030 2031 /* main receive path */ 2032 2033 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata, 2034 struct ieee80211_rx_data *rx, 2035 struct ieee80211_hdr *hdr) 2036 { 2037 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type); 2038 int multicast = is_multicast_ether_addr(hdr->addr1); 2039 2040 switch (sdata->vif.type) { 2041 case NL80211_IFTYPE_STATION: 2042 if (!bssid) 2043 return 0; 2044 if (!multicast && 2045 compare_ether_addr(sdata->dev->dev_addr, hdr->addr1) != 0) { 2046 if (!(sdata->dev->flags & IFF_PROMISC)) 2047 return 0; 2048 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2049 } 2050 break; 2051 case NL80211_IFTYPE_ADHOC: 2052 if (!bssid) 2053 return 0; 2054 if (ieee80211_is_beacon(hdr->frame_control)) { 2055 return 1; 2056 } 2057 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) { 2058 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2059 return 0; 2060 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2061 } else if (!multicast && 2062 compare_ether_addr(sdata->dev->dev_addr, 2063 hdr->addr1) != 0) { 2064 if (!(sdata->dev->flags & IFF_PROMISC)) 2065 return 0; 2066 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2067 } else if (!rx->sta) { 2068 int rate_idx; 2069 if (rx->status->flag & RX_FLAG_HT) 2070 rate_idx = 0; /* TODO: HT rates */ 2071 else 2072 rate_idx = rx->status->rate_idx; 2073 rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2, 2074 BIT(rate_idx)); 2075 } 2076 break; 2077 case NL80211_IFTYPE_MESH_POINT: 2078 if (!multicast && 2079 compare_ether_addr(sdata->dev->dev_addr, 2080 hdr->addr1) != 0) { 2081 if (!(sdata->dev->flags & IFF_PROMISC)) 2082 return 0; 2083 2084 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2085 } 2086 break; 2087 case NL80211_IFTYPE_AP_VLAN: 2088 case NL80211_IFTYPE_AP: 2089 if (!bssid) { 2090 if (compare_ether_addr(sdata->dev->dev_addr, 2091 hdr->addr1)) 2092 return 0; 2093 } else if (!ieee80211_bssid_match(bssid, 2094 sdata->dev->dev_addr)) { 2095 if (!(rx->flags & IEEE80211_RX_IN_SCAN)) 2096 return 0; 2097 rx->flags &= ~IEEE80211_RX_RA_MATCH; 2098 } 2099 break; 2100 case NL80211_IFTYPE_WDS: 2101 if (bssid || !ieee80211_is_data(hdr->frame_control)) 2102 return 0; 2103 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2)) 2104 return 0; 2105 break; 2106 case NL80211_IFTYPE_MONITOR: 2107 /* take everything */ 2108 break; 2109 case NL80211_IFTYPE_UNSPECIFIED: 2110 case __NL80211_IFTYPE_AFTER_LAST: 2111 /* should never get here */ 2112 WARN_ON(1); 2113 break; 2114 } 2115 2116 return 1; 2117 } 2118 2119 /* 2120 * This is the actual Rx frames handler. as it blongs to Rx path it must 2121 * be called with rcu_read_lock protection. 2122 */ 2123 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, 2124 struct sk_buff *skb, 2125 struct ieee80211_rate *rate) 2126 { 2127 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2128 struct ieee80211_local *local = hw_to_local(hw); 2129 struct ieee80211_sub_if_data *sdata; 2130 struct ieee80211_hdr *hdr; 2131 struct ieee80211_rx_data rx; 2132 int prepares; 2133 struct ieee80211_sub_if_data *prev = NULL; 2134 struct sk_buff *skb_new; 2135 2136 hdr = (struct ieee80211_hdr *)skb->data; 2137 memset(&rx, 0, sizeof(rx)); 2138 rx.skb = skb; 2139 rx.local = local; 2140 2141 rx.status = status; 2142 rx.rate = rate; 2143 2144 if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control)) 2145 local->dot11ReceivedFragmentCount++; 2146 2147 rx.sta = sta_info_get(local, hdr->addr2); 2148 if (rx.sta) { 2149 rx.sdata = rx.sta->sdata; 2150 rx.dev = rx.sta->sdata->dev; 2151 } 2152 2153 if ((status->flag & RX_FLAG_MMIC_ERROR)) { 2154 ieee80211_rx_michael_mic_report(hdr, &rx); 2155 return; 2156 } 2157 2158 if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) || 2159 test_bit(SCAN_OFF_CHANNEL, &local->scanning))) 2160 rx.flags |= IEEE80211_RX_IN_SCAN; 2161 2162 ieee80211_parse_qos(&rx); 2163 ieee80211_verify_alignment(&rx); 2164 2165 skb = rx.skb; 2166 2167 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 2168 if (!netif_running(sdata->dev)) 2169 continue; 2170 2171 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) 2172 continue; 2173 2174 rx.flags |= IEEE80211_RX_RA_MATCH; 2175 prepares = prepare_for_handlers(sdata, &rx, hdr); 2176 2177 if (!prepares) 2178 continue; 2179 2180 /* 2181 * frame is destined for this interface, but if it's not 2182 * also for the previous one we handle that after the 2183 * loop to avoid copying the SKB once too much 2184 */ 2185 2186 if (!prev) { 2187 prev = sdata; 2188 continue; 2189 } 2190 2191 /* 2192 * frame was destined for the previous interface 2193 * so invoke RX handlers for it 2194 */ 2195 2196 skb_new = skb_copy(skb, GFP_ATOMIC); 2197 if (!skb_new) { 2198 if (net_ratelimit()) 2199 printk(KERN_DEBUG "%s: failed to copy " 2200 "multicast frame for %s\n", 2201 wiphy_name(local->hw.wiphy), 2202 prev->dev->name); 2203 continue; 2204 } 2205 ieee80211_invoke_rx_handlers(prev, &rx, skb_new); 2206 prev = sdata; 2207 } 2208 if (prev) 2209 ieee80211_invoke_rx_handlers(prev, &rx, skb); 2210 else 2211 dev_kfree_skb(skb); 2212 } 2213 2214 #define SEQ_MODULO 0x1000 2215 #define SEQ_MASK 0xfff 2216 2217 static inline int seq_less(u16 sq1, u16 sq2) 2218 { 2219 return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1); 2220 } 2221 2222 static inline u16 seq_inc(u16 sq) 2223 { 2224 return (sq + 1) & SEQ_MASK; 2225 } 2226 2227 static inline u16 seq_sub(u16 sq1, u16 sq2) 2228 { 2229 return (sq1 - sq2) & SEQ_MASK; 2230 } 2231 2232 2233 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw, 2234 struct tid_ampdu_rx *tid_agg_rx, 2235 int index) 2236 { 2237 struct ieee80211_supported_band *sband; 2238 struct ieee80211_rate *rate; 2239 struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; 2240 struct ieee80211_rx_status *status; 2241 2242 if (!skb) 2243 goto no_frame; 2244 2245 status = IEEE80211_SKB_RXCB(skb); 2246 2247 /* release the reordered frames to stack */ 2248 sband = hw->wiphy->bands[status->band]; 2249 if (status->flag & RX_FLAG_HT) 2250 rate = sband->bitrates; /* TODO: HT rates */ 2251 else 2252 rate = &sband->bitrates[status->rate_idx]; 2253 __ieee80211_rx_handle_packet(hw, skb, rate); 2254 tid_agg_rx->stored_mpdu_num--; 2255 tid_agg_rx->reorder_buf[index] = NULL; 2256 2257 no_frame: 2258 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num); 2259 } 2260 2261 2262 /* 2263 * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If 2264 * the skb was added to the buffer longer than this time ago, the earlier 2265 * frames that have not yet been received are assumed to be lost and the skb 2266 * can be released for processing. This may also release other skb's from the 2267 * reorder buffer if there are no additional gaps between the frames. 2268 */ 2269 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10) 2270 2271 /* 2272 * As it function blongs to Rx path it must be called with 2273 * the proper rcu_read_lock protection for its flow. 2274 */ 2275 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw, 2276 struct tid_ampdu_rx *tid_agg_rx, 2277 struct sk_buff *skb, 2278 u16 mpdu_seq_num, 2279 int bar_req) 2280 { 2281 u16 head_seq_num, buf_size; 2282 int index; 2283 2284 buf_size = tid_agg_rx->buf_size; 2285 head_seq_num = tid_agg_rx->head_seq_num; 2286 2287 /* frame with out of date sequence number */ 2288 if (seq_less(mpdu_seq_num, head_seq_num)) { 2289 dev_kfree_skb(skb); 2290 return 1; 2291 } 2292 2293 /* if frame sequence number exceeds our buffering window size or 2294 * block Ack Request arrived - release stored frames */ 2295 if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) { 2296 /* new head to the ordering buffer */ 2297 if (bar_req) 2298 head_seq_num = mpdu_seq_num; 2299 else 2300 head_seq_num = 2301 seq_inc(seq_sub(mpdu_seq_num, buf_size)); 2302 /* release stored frames up to new head to stack */ 2303 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) { 2304 index = seq_sub(tid_agg_rx->head_seq_num, 2305 tid_agg_rx->ssn) 2306 % tid_agg_rx->buf_size; 2307 ieee80211_release_reorder_frame(hw, tid_agg_rx, 2308 index); 2309 } 2310 if (bar_req) 2311 return 1; 2312 } 2313 2314 /* now the new frame is always in the range of the reordering */ 2315 /* buffer window */ 2316 index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) 2317 % tid_agg_rx->buf_size; 2318 /* check if we already stored this frame */ 2319 if (tid_agg_rx->reorder_buf[index]) { 2320 dev_kfree_skb(skb); 2321 return 1; 2322 } 2323 2324 /* if arrived mpdu is in the right order and nothing else stored */ 2325 /* release it immediately */ 2326 if (mpdu_seq_num == tid_agg_rx->head_seq_num && 2327 tid_agg_rx->stored_mpdu_num == 0) { 2328 tid_agg_rx->head_seq_num = 2329 seq_inc(tid_agg_rx->head_seq_num); 2330 return 0; 2331 } 2332 2333 /* put the frame in the reordering buffer */ 2334 tid_agg_rx->reorder_buf[index] = skb; 2335 tid_agg_rx->reorder_time[index] = jiffies; 2336 tid_agg_rx->stored_mpdu_num++; 2337 /* release the buffer until next missing frame */ 2338 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) 2339 % tid_agg_rx->buf_size; 2340 if (!tid_agg_rx->reorder_buf[index] && 2341 tid_agg_rx->stored_mpdu_num > 1) { 2342 /* 2343 * No buffers ready to be released, but check whether any 2344 * frames in the reorder buffer have timed out. 2345 */ 2346 int j; 2347 int skipped = 1; 2348 for (j = (index + 1) % tid_agg_rx->buf_size; j != index; 2349 j = (j + 1) % tid_agg_rx->buf_size) { 2350 if (tid_agg_rx->reorder_buf[j] == NULL) { 2351 skipped++; 2352 continue; 2353 } 2354 if (!time_after(jiffies, tid_agg_rx->reorder_time[j] + 2355 HZ / 10)) 2356 break; 2357 2358 #ifdef CONFIG_MAC80211_HT_DEBUG 2359 if (net_ratelimit()) 2360 printk(KERN_DEBUG "%s: release an RX reorder " 2361 "frame due to timeout on earlier " 2362 "frames\n", 2363 wiphy_name(hw->wiphy)); 2364 #endif 2365 ieee80211_release_reorder_frame(hw, tid_agg_rx, j); 2366 2367 /* 2368 * Increment the head seq# also for the skipped slots. 2369 */ 2370 tid_agg_rx->head_seq_num = 2371 (tid_agg_rx->head_seq_num + skipped) & 2372 SEQ_MASK; 2373 skipped = 0; 2374 } 2375 } else while (tid_agg_rx->reorder_buf[index]) { 2376 ieee80211_release_reorder_frame(hw, tid_agg_rx, index); 2377 index = seq_sub(tid_agg_rx->head_seq_num, 2378 tid_agg_rx->ssn) % tid_agg_rx->buf_size; 2379 } 2380 return 1; 2381 } 2382 2383 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local, 2384 struct sk_buff *skb) 2385 { 2386 struct ieee80211_hw *hw = &local->hw; 2387 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 2388 struct sta_info *sta; 2389 struct tid_ampdu_rx *tid_agg_rx; 2390 u16 sc; 2391 u16 mpdu_seq_num; 2392 u8 ret = 0; 2393 int tid; 2394 2395 sta = sta_info_get(local, hdr->addr2); 2396 if (!sta) 2397 return ret; 2398 2399 /* filter the QoS data rx stream according to 2400 * STA/TID and check if this STA/TID is on aggregation */ 2401 if (!ieee80211_is_data_qos(hdr->frame_control)) 2402 goto end_reorder; 2403 2404 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 2405 2406 if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) 2407 goto end_reorder; 2408 2409 tid_agg_rx = sta->ampdu_mlme.tid_rx[tid]; 2410 2411 /* qos null data frames are excluded */ 2412 if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC))) 2413 goto end_reorder; 2414 2415 /* new un-ordered ampdu frame - process it */ 2416 2417 /* reset session timer */ 2418 if (tid_agg_rx->timeout) 2419 mod_timer(&tid_agg_rx->session_timer, 2420 TU_TO_EXP_TIME(tid_agg_rx->timeout)); 2421 2422 /* if this mpdu is fragmented - terminate rx aggregation session */ 2423 sc = le16_to_cpu(hdr->seq_ctrl); 2424 if (sc & IEEE80211_SCTL_FRAG) { 2425 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr, 2426 tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP); 2427 ret = 1; 2428 goto end_reorder; 2429 } 2430 2431 /* according to mpdu sequence number deal with reordering buffer */ 2432 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; 2433 ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, 2434 mpdu_seq_num, 0); 2435 end_reorder: 2436 return ret; 2437 } 2438 2439 /* 2440 * This is the receive path handler. It is called by a low level driver when an 2441 * 802.11 MPDU is received from the hardware. 2442 */ 2443 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) 2444 { 2445 struct ieee80211_local *local = hw_to_local(hw); 2446 struct ieee80211_rate *rate = NULL; 2447 struct ieee80211_supported_band *sband; 2448 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 2449 2450 if (WARN_ON(status->band < 0 || 2451 status->band >= IEEE80211_NUM_BANDS)) 2452 goto drop; 2453 2454 sband = local->hw.wiphy->bands[status->band]; 2455 if (WARN_ON(!sband)) 2456 goto drop; 2457 2458 /* 2459 * If we're suspending, it is possible although not too likely 2460 * that we'd be receiving frames after having already partially 2461 * quiesced the stack. We can't process such frames then since 2462 * that might, for example, cause stations to be added or other 2463 * driver callbacks be invoked. 2464 */ 2465 if (unlikely(local->quiescing || local->suspended)) 2466 goto drop; 2467 2468 /* 2469 * The same happens when we're not even started, 2470 * but that's worth a warning. 2471 */ 2472 if (WARN_ON(!local->started)) 2473 goto drop; 2474 2475 if (status->flag & RX_FLAG_HT) { 2476 /* rate_idx is MCS index */ 2477 if (WARN_ON(status->rate_idx < 0 || 2478 status->rate_idx >= 76)) 2479 goto drop; 2480 /* HT rates are not in the table - use the highest legacy rate 2481 * for now since other parts of mac80211 may not yet be fully 2482 * MCS aware. */ 2483 rate = &sband->bitrates[sband->n_bitrates - 1]; 2484 } else { 2485 if (WARN_ON(status->rate_idx < 0 || 2486 status->rate_idx >= sband->n_bitrates)) 2487 goto drop; 2488 rate = &sband->bitrates[status->rate_idx]; 2489 } 2490 2491 /* 2492 * key references and virtual interfaces are protected using RCU 2493 * and this requires that we are in a read-side RCU section during 2494 * receive processing 2495 */ 2496 rcu_read_lock(); 2497 2498 /* 2499 * Frames with failed FCS/PLCP checksum are not returned, 2500 * all other frames are returned without radiotap header 2501 * if it was previously present. 2502 * Also, frames with less than 16 bytes are dropped. 2503 */ 2504 skb = ieee80211_rx_monitor(local, skb, rate); 2505 if (!skb) { 2506 rcu_read_unlock(); 2507 return; 2508 } 2509 2510 /* 2511 * In theory, the block ack reordering should happen after duplicate 2512 * removal (ieee80211_rx_h_check(), which is an RX handler). As such, 2513 * the call to ieee80211_rx_reorder_ampdu() should really be moved to 2514 * happen as a new RX handler between ieee80211_rx_h_check and 2515 * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for 2516 * the time being, the call can be here since RX reorder buf processing 2517 * will implicitly skip duplicates. We could, in theory at least, 2518 * process frames that ieee80211_rx_h_passive_scan would drop (e.g., 2519 * frames from other than operational channel), but that should not 2520 * happen in normal networks. 2521 */ 2522 if (!ieee80211_rx_reorder_ampdu(local, skb)) 2523 __ieee80211_rx_handle_packet(hw, skb, rate); 2524 2525 rcu_read_unlock(); 2526 2527 return; 2528 drop: 2529 kfree_skb(skb); 2530 } 2531 EXPORT_SYMBOL(ieee80211_rx); 2532 2533 /* This is a version of the rx handler that can be called from hard irq 2534 * context. Post the skb on the queue and schedule the tasklet */ 2535 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) 2536 { 2537 struct ieee80211_local *local = hw_to_local(hw); 2538 2539 BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb)); 2540 2541 skb->pkt_type = IEEE80211_RX_MSG; 2542 skb_queue_tail(&local->skb_queue, skb); 2543 tasklet_schedule(&local->tasklet); 2544 } 2545 EXPORT_SYMBOL(ieee80211_rx_irqsafe); 2546