rx.c 70 KB

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  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. #include <linux/jiffies.h>
  12. #include <linux/kernel.h>
  13. #include <linux/skbuff.h>
  14. #include <linux/netdevice.h>
  15. #include <linux/etherdevice.h>
  16. #include <linux/rcupdate.h>
  17. #include <net/mac80211.h>
  18. #include <net/ieee80211_radiotap.h>
  19. #include "ieee80211_i.h"
  20. #include "driver-ops.h"
  21. #include "led.h"
  22. #include "mesh.h"
  23. #include "wep.h"
  24. #include "wpa.h"
  25. #include "tkip.h"
  26. #include "wme.h"
  27. static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  28. struct tid_ampdu_rx *tid_agg_rx,
  29. struct sk_buff *skb,
  30. u16 mpdu_seq_num,
  31. int bar_req);
  32. /*
  33. * monitor mode reception
  34. *
  35. * This function cleans up the SKB, i.e. it removes all the stuff
  36. * only useful for monitoring.
  37. */
  38. static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  39. struct sk_buff *skb,
  40. int rtap_len)
  41. {
  42. skb_pull(skb, rtap_len);
  43. if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  44. if (likely(skb->len > FCS_LEN))
  45. skb_trim(skb, skb->len - FCS_LEN);
  46. else {
  47. /* driver bug */
  48. WARN_ON(1);
  49. dev_kfree_skb(skb);
  50. skb = NULL;
  51. }
  52. }
  53. return skb;
  54. }
  55. static inline int should_drop_frame(struct sk_buff *skb,
  56. int present_fcs_len,
  57. int radiotap_len)
  58. {
  59. struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  60. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  61. if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  62. return 1;
  63. if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  64. return 1;
  65. if (ieee80211_is_ctl(hdr->frame_control) &&
  66. !ieee80211_is_pspoll(hdr->frame_control) &&
  67. !ieee80211_is_back_req(hdr->frame_control))
  68. return 1;
  69. return 0;
  70. }
  71. static int
  72. ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  73. struct ieee80211_rx_status *status)
  74. {
  75. int len;
  76. /* always present fields */
  77. len = sizeof(struct ieee80211_radiotap_header) + 9;
  78. if (status->flag & RX_FLAG_TSFT)
  79. len += 8;
  80. if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  81. len += 1;
  82. if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  83. len += 1;
  84. if (len & 1) /* padding for RX_FLAGS if necessary */
  85. len++;
  86. /* make sure radiotap starts at a naturally aligned address */
  87. if (len % 8)
  88. len = roundup(len, 8);
  89. return len;
  90. }
  91. /*
  92. * ieee80211_add_rx_radiotap_header - add radiotap header
  93. *
  94. * add a radiotap header containing all the fields which the hardware provided.
  95. */
  96. static void
  97. ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
  98. struct sk_buff *skb,
  99. struct ieee80211_rate *rate,
  100. int rtap_len)
  101. {
  102. struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  103. struct ieee80211_radiotap_header *rthdr;
  104. unsigned char *pos;
  105. rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
  106. memset(rthdr, 0, rtap_len);
  107. /* radiotap header, set always present flags */
  108. rthdr->it_present =
  109. cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
  110. (1 << IEEE80211_RADIOTAP_CHANNEL) |
  111. (1 << IEEE80211_RADIOTAP_ANTENNA) |
  112. (1 << IEEE80211_RADIOTAP_RX_FLAGS));
  113. rthdr->it_len = cpu_to_le16(rtap_len);
  114. pos = (unsigned char *)(rthdr+1);
  115. /* the order of the following fields is important */
  116. /* IEEE80211_RADIOTAP_TSFT */
  117. if (status->flag & RX_FLAG_TSFT) {
  118. *(__le64 *)pos = cpu_to_le64(status->mactime);
  119. rthdr->it_present |=
  120. cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
  121. pos += 8;
  122. }
  123. /* IEEE80211_RADIOTAP_FLAGS */
  124. if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
  125. *pos |= IEEE80211_RADIOTAP_F_FCS;
  126. if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  127. *pos |= IEEE80211_RADIOTAP_F_BADFCS;
  128. if (status->flag & RX_FLAG_SHORTPRE)
  129. *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
  130. pos++;
  131. /* IEEE80211_RADIOTAP_RATE */
  132. if (status->flag & RX_FLAG_HT) {
  133. /*
  134. * TODO: add following information into radiotap header once
  135. * suitable fields are defined for it:
  136. * - MCS index (status->rate_idx)
  137. * - HT40 (status->flag & RX_FLAG_40MHZ)
  138. * - short-GI (status->flag & RX_FLAG_SHORT_GI)
  139. */
  140. *pos = 0;
  141. } else {
  142. rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
  143. *pos = rate->bitrate / 5;
  144. }
  145. pos++;
  146. /* IEEE80211_RADIOTAP_CHANNEL */
  147. *(__le16 *)pos = cpu_to_le16(status->freq);
  148. pos += 2;
  149. if (status->band == IEEE80211_BAND_5GHZ)
  150. *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
  151. IEEE80211_CHAN_5GHZ);
  152. else if (rate->flags & IEEE80211_RATE_ERP_G)
  153. *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
  154. IEEE80211_CHAN_2GHZ);
  155. else
  156. *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
  157. IEEE80211_CHAN_2GHZ);
  158. pos += 2;
  159. /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
  160. if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
  161. *pos = status->signal;
  162. rthdr->it_present |=
  163. cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
  164. pos++;
  165. }
  166. /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
  167. if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
  168. *pos = status->noise;
  169. rthdr->it_present |=
  170. cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
  171. pos++;
  172. }
  173. /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
  174. /* IEEE80211_RADIOTAP_ANTENNA */
  175. *pos = status->antenna;
  176. pos++;
  177. /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
  178. /* IEEE80211_RADIOTAP_RX_FLAGS */
  179. /* ensure 2 byte alignment for the 2 byte field as required */
  180. if ((pos - (unsigned char *)rthdr) & 1)
  181. pos++;
  182. if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
  183. *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
  184. pos += 2;
  185. }
  186. /*
  187. * This function copies a received frame to all monitor interfaces and
  188. * returns a cleaned-up SKB that no longer includes the FCS nor the
  189. * radiotap header the driver might have added.
  190. */
  191. static struct sk_buff *
  192. ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  193. struct ieee80211_rate *rate)
  194. {
  195. struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
  196. struct ieee80211_sub_if_data *sdata;
  197. int needed_headroom = 0;
  198. struct sk_buff *skb, *skb2;
  199. struct net_device *prev_dev = NULL;
  200. int present_fcs_len = 0;
  201. int rtap_len = 0;
  202. /*
  203. * First, we may need to make a copy of the skb because
  204. * (1) we need to modify it for radiotap (if not present), and
  205. * (2) the other RX handlers will modify the skb we got.
  206. *
  207. * We don't need to, of course, if we aren't going to return
  208. * the SKB because it has a bad FCS/PLCP checksum.
  209. */
  210. if (status->flag & RX_FLAG_RADIOTAP)
  211. rtap_len = ieee80211_get_radiotap_len(origskb->data);
  212. else
  213. /* room for the radiotap header based on driver features */
  214. needed_headroom = ieee80211_rx_radiotap_len(local, status);
  215. if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
  216. present_fcs_len = FCS_LEN;
  217. if (!local->monitors) {
  218. if (should_drop_frame(origskb, present_fcs_len, rtap_len)) {
  219. dev_kfree_skb(origskb);
  220. return NULL;
  221. }
  222. return remove_monitor_info(local, origskb, rtap_len);
  223. }
  224. if (should_drop_frame(origskb, present_fcs_len, rtap_len)) {
  225. /* only need to expand headroom if necessary */
  226. skb = origskb;
  227. origskb = NULL;
  228. /*
  229. * This shouldn't trigger often because most devices have an
  230. * RX header they pull before we get here, and that should
  231. * be big enough for our radiotap information. We should
  232. * probably export the length to drivers so that we can have
  233. * them allocate enough headroom to start with.
  234. */
  235. if (skb_headroom(skb) < needed_headroom &&
  236. pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
  237. dev_kfree_skb(skb);
  238. return NULL;
  239. }
  240. } else {
  241. /*
  242. * Need to make a copy and possibly remove radiotap header
  243. * and FCS from the original.
  244. */
  245. skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
  246. origskb = remove_monitor_info(local, origskb, rtap_len);
  247. if (!skb)
  248. return origskb;
  249. }
  250. /* if necessary, prepend radiotap information */
  251. if (!(status->flag & RX_FLAG_RADIOTAP))
  252. ieee80211_add_rx_radiotap_header(local, skb, rate,
  253. needed_headroom);
  254. skb_reset_mac_header(skb);
  255. skb->ip_summed = CHECKSUM_UNNECESSARY;
  256. skb->pkt_type = PACKET_OTHERHOST;
  257. skb->protocol = htons(ETH_P_802_2);
  258. list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  259. if (!netif_running(sdata->dev))
  260. continue;
  261. if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
  262. continue;
  263. if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
  264. continue;
  265. if (prev_dev) {
  266. skb2 = skb_clone(skb, GFP_ATOMIC);
  267. if (skb2) {
  268. skb2->dev = prev_dev;
  269. netif_rx(skb2);
  270. }
  271. }
  272. prev_dev = sdata->dev;
  273. sdata->dev->stats.rx_packets++;
  274. sdata->dev->stats.rx_bytes += skb->len;
  275. }
  276. if (prev_dev) {
  277. skb->dev = prev_dev;
  278. netif_rx(skb);
  279. } else
  280. dev_kfree_skb(skb);
  281. return origskb;
  282. }
  283. static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
  284. {
  285. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  286. int tid;
  287. /* does the frame have a qos control field? */
  288. if (ieee80211_is_data_qos(hdr->frame_control)) {
  289. u8 *qc = ieee80211_get_qos_ctl(hdr);
  290. /* frame has qos control */
  291. tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
  292. if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
  293. rx->flags |= IEEE80211_RX_AMSDU;
  294. else
  295. rx->flags &= ~IEEE80211_RX_AMSDU;
  296. } else {
  297. /*
  298. * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
  299. *
  300. * Sequence numbers for management frames, QoS data
  301. * frames with a broadcast/multicast address in the
  302. * Address 1 field, and all non-QoS data frames sent
  303. * by QoS STAs are assigned using an additional single
  304. * modulo-4096 counter, [...]
  305. *
  306. * We also use that counter for non-QoS STAs.
  307. */
  308. tid = NUM_RX_DATA_QUEUES - 1;
  309. }
  310. rx->queue = tid;
  311. /* Set skb->priority to 1d tag if highest order bit of TID is not set.
  312. * For now, set skb->priority to 0 for other cases. */
  313. rx->skb->priority = (tid > 7) ? 0 : tid;
  314. }
  315. /**
  316. * DOC: Packet alignment
  317. *
  318. * Drivers always need to pass packets that are aligned to two-byte boundaries
  319. * to the stack.
  320. *
  321. * Additionally, should, if possible, align the payload data in a way that
  322. * guarantees that the contained IP header is aligned to a four-byte
  323. * boundary. In the case of regular frames, this simply means aligning the
  324. * payload to a four-byte boundary (because either the IP header is directly
  325. * contained, or IV/RFC1042 headers that have a length divisible by four are
  326. * in front of it).
  327. *
  328. * With A-MSDU frames, however, the payload data address must yield two modulo
  329. * four because there are 14-byte 802.3 headers within the A-MSDU frames that
  330. * push the IP header further back to a multiple of four again. Thankfully, the
  331. * specs were sane enough this time around to require padding each A-MSDU
  332. * subframe to a length that is a multiple of four.
  333. *
  334. * Padding like Atheros hardware adds which is inbetween the 802.11 header and
  335. * the payload is not supported, the driver is required to move the 802.11
  336. * header to be directly in front of the payload in that case.
  337. */
  338. static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
  339. {
  340. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  341. int hdrlen;
  342. #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
  343. return;
  344. #endif
  345. if (WARN_ONCE((unsigned long)rx->skb->data & 1,
  346. "unaligned packet at 0x%p\n", rx->skb->data))
  347. return;
  348. if (!ieee80211_is_data_present(hdr->frame_control))
  349. return;
  350. hdrlen = ieee80211_hdrlen(hdr->frame_control);
  351. if (rx->flags & IEEE80211_RX_AMSDU)
  352. hdrlen += ETH_HLEN;
  353. WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
  354. "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
  355. }
  356. /* rx handlers */
  357. static ieee80211_rx_result debug_noinline
  358. ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
  359. {
  360. struct ieee80211_local *local = rx->local;
  361. struct sk_buff *skb = rx->skb;
  362. if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
  363. return ieee80211_scan_rx(rx->sdata, skb);
  364. if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
  365. (rx->flags & IEEE80211_RX_IN_SCAN))) {
  366. /* drop all the other packets during a software scan anyway */
  367. if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
  368. dev_kfree_skb(skb);
  369. return RX_QUEUED;
  370. }
  371. if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
  372. /* scanning finished during invoking of handlers */
  373. I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
  374. return RX_DROP_UNUSABLE;
  375. }
  376. return RX_CONTINUE;
  377. }
  378. static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
  379. {
  380. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  381. if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
  382. return 0;
  383. return ieee80211_is_robust_mgmt_frame(hdr);
  384. }
  385. static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
  386. {
  387. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  388. if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
  389. return 0;
  390. return ieee80211_is_robust_mgmt_frame(hdr);
  391. }
  392. /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
  393. static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
  394. {
  395. struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
  396. struct ieee80211_mmie *mmie;
  397. if (skb->len < 24 + sizeof(*mmie) ||
  398. !is_multicast_ether_addr(hdr->da))
  399. return -1;
  400. if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
  401. return -1; /* not a robust management frame */
  402. mmie = (struct ieee80211_mmie *)
  403. (skb->data + skb->len - sizeof(*mmie));
  404. if (mmie->element_id != WLAN_EID_MMIE ||
  405. mmie->length != sizeof(*mmie) - 2)
  406. return -1;
  407. return le16_to_cpu(mmie->key_id);
  408. }
  409. static ieee80211_rx_result
  410. ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
  411. {
  412. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  413. unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
  414. char *dev_addr = rx->dev->dev_addr;
  415. if (ieee80211_is_data(hdr->frame_control)) {
  416. if (is_multicast_ether_addr(hdr->addr1)) {
  417. if (ieee80211_has_tods(hdr->frame_control) ||
  418. !ieee80211_has_fromds(hdr->frame_control))
  419. return RX_DROP_MONITOR;
  420. if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
  421. return RX_DROP_MONITOR;
  422. } else {
  423. if (!ieee80211_has_a4(hdr->frame_control))
  424. return RX_DROP_MONITOR;
  425. if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
  426. return RX_DROP_MONITOR;
  427. }
  428. }
  429. /* If there is not an established peer link and this is not a peer link
  430. * establisment frame, beacon or probe, drop the frame.
  431. */
  432. if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
  433. struct ieee80211_mgmt *mgmt;
  434. if (!ieee80211_is_mgmt(hdr->frame_control))
  435. return RX_DROP_MONITOR;
  436. if (ieee80211_is_action(hdr->frame_control)) {
  437. mgmt = (struct ieee80211_mgmt *)hdr;
  438. if (mgmt->u.action.category != PLINK_CATEGORY)
  439. return RX_DROP_MONITOR;
  440. return RX_CONTINUE;
  441. }
  442. if (ieee80211_is_probe_req(hdr->frame_control) ||
  443. ieee80211_is_probe_resp(hdr->frame_control) ||
  444. ieee80211_is_beacon(hdr->frame_control))
  445. return RX_CONTINUE;
  446. return RX_DROP_MONITOR;
  447. }
  448. #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
  449. if (ieee80211_is_data(hdr->frame_control) &&
  450. is_multicast_ether_addr(hdr->addr1) &&
  451. mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
  452. return RX_DROP_MONITOR;
  453. #undef msh_h_get
  454. return RX_CONTINUE;
  455. }
  456. static ieee80211_rx_result debug_noinline
  457. ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
  458. {
  459. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  460. /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
  461. if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
  462. if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
  463. rx->sta->last_seq_ctrl[rx->queue] ==
  464. hdr->seq_ctrl)) {
  465. if (rx->flags & IEEE80211_RX_RA_MATCH) {
  466. rx->local->dot11FrameDuplicateCount++;
  467. rx->sta->num_duplicates++;
  468. }
  469. return RX_DROP_MONITOR;
  470. } else
  471. rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
  472. }
  473. if (unlikely(rx->skb->len < 16)) {
  474. I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
  475. return RX_DROP_MONITOR;
  476. }
  477. /* Drop disallowed frame classes based on STA auth/assoc state;
  478. * IEEE 802.11, Chap 5.5.
  479. *
  480. * mac80211 filters only based on association state, i.e. it drops
  481. * Class 3 frames from not associated stations. hostapd sends
  482. * deauth/disassoc frames when needed. In addition, hostapd is
  483. * responsible for filtering on both auth and assoc states.
  484. */
  485. if (ieee80211_vif_is_mesh(&rx->sdata->vif))
  486. return ieee80211_rx_mesh_check(rx);
  487. if (unlikely((ieee80211_is_data(hdr->frame_control) ||
  488. ieee80211_is_pspoll(hdr->frame_control)) &&
  489. rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
  490. (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
  491. if ((!ieee80211_has_fromds(hdr->frame_control) &&
  492. !ieee80211_has_tods(hdr->frame_control) &&
  493. ieee80211_is_data(hdr->frame_control)) ||
  494. !(rx->flags & IEEE80211_RX_RA_MATCH)) {
  495. /* Drop IBSS frames and frames for other hosts
  496. * silently. */
  497. return RX_DROP_MONITOR;
  498. }
  499. return RX_DROP_MONITOR;
  500. }
  501. return RX_CONTINUE;
  502. }
  503. static ieee80211_rx_result debug_noinline
  504. ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
  505. {
  506. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  507. int keyidx;
  508. int hdrlen;
  509. ieee80211_rx_result result = RX_DROP_UNUSABLE;
  510. struct ieee80211_key *stakey = NULL;
  511. int mmie_keyidx = -1;
  512. /*
  513. * Key selection 101
  514. *
  515. * There are four types of keys:
  516. * - GTK (group keys)
  517. * - IGTK (group keys for management frames)
  518. * - PTK (pairwise keys)
  519. * - STK (station-to-station pairwise keys)
  520. *
  521. * When selecting a key, we have to distinguish between multicast
  522. * (including broadcast) and unicast frames, the latter can only
  523. * use PTKs and STKs while the former always use GTKs and IGTKs.
  524. * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
  525. * unicast frames can also use key indices like GTKs. Hence, if we
  526. * don't have a PTK/STK we check the key index for a WEP key.
  527. *
  528. * Note that in a regular BSS, multicast frames are sent by the
  529. * AP only, associated stations unicast the frame to the AP first
  530. * which then multicasts it on their behalf.
  531. *
  532. * There is also a slight problem in IBSS mode: GTKs are negotiated
  533. * with each station, that is something we don't currently handle.
  534. * The spec seems to expect that one negotiates the same key with
  535. * every station but there's no such requirement; VLANs could be
  536. * possible.
  537. */
  538. /*
  539. * No point in finding a key and decrypting if the frame is neither
  540. * addressed to us nor a multicast frame.
  541. */
  542. if (!(rx->flags & IEEE80211_RX_RA_MATCH))
  543. return RX_CONTINUE;
  544. if (rx->sta)
  545. stakey = rcu_dereference(rx->sta->key);
  546. if (!ieee80211_has_protected(hdr->frame_control))
  547. mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
  548. if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
  549. rx->key = stakey;
  550. /* Skip decryption if the frame is not protected. */
  551. if (!ieee80211_has_protected(hdr->frame_control))
  552. return RX_CONTINUE;
  553. } else if (mmie_keyidx >= 0) {
  554. /* Broadcast/multicast robust management frame / BIP */
  555. if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
  556. (rx->status->flag & RX_FLAG_IV_STRIPPED))
  557. return RX_CONTINUE;
  558. if (mmie_keyidx < NUM_DEFAULT_KEYS ||
  559. mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
  560. return RX_DROP_MONITOR; /* unexpected BIP keyidx */
  561. rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
  562. } else if (!ieee80211_has_protected(hdr->frame_control)) {
  563. /*
  564. * The frame was not protected, so skip decryption. However, we
  565. * need to set rx->key if there is a key that could have been
  566. * used so that the frame may be dropped if encryption would
  567. * have been expected.
  568. */
  569. struct ieee80211_key *key = NULL;
  570. if (ieee80211_is_mgmt(hdr->frame_control) &&
  571. is_multicast_ether_addr(hdr->addr1) &&
  572. (key = rcu_dereference(rx->sdata->default_mgmt_key)))
  573. rx->key = key;
  574. else if ((key = rcu_dereference(rx->sdata->default_key)))
  575. rx->key = key;
  576. return RX_CONTINUE;
  577. } else {
  578. /*
  579. * The device doesn't give us the IV so we won't be
  580. * able to look up the key. That's ok though, we
  581. * don't need to decrypt the frame, we just won't
  582. * be able to keep statistics accurate.
  583. * Except for key threshold notifications, should
  584. * we somehow allow the driver to tell us which key
  585. * the hardware used if this flag is set?
  586. */
  587. if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
  588. (rx->status->flag & RX_FLAG_IV_STRIPPED))
  589. return RX_CONTINUE;
  590. hdrlen = ieee80211_hdrlen(hdr->frame_control);
  591. if (rx->skb->len < 8 + hdrlen)
  592. return RX_DROP_UNUSABLE; /* TODO: count this? */
  593. /*
  594. * no need to call ieee80211_wep_get_keyidx,
  595. * it verifies a bunch of things we've done already
  596. */
  597. keyidx = rx->skb->data[hdrlen + 3] >> 6;
  598. rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
  599. /*
  600. * RSNA-protected unicast frames should always be sent with
  601. * pairwise or station-to-station keys, but for WEP we allow
  602. * using a key index as well.
  603. */
  604. if (rx->key && rx->key->conf.alg != ALG_WEP &&
  605. !is_multicast_ether_addr(hdr->addr1))
  606. rx->key = NULL;
  607. }
  608. if (rx->key) {
  609. rx->key->tx_rx_count++;
  610. /* TODO: add threshold stuff again */
  611. } else {
  612. return RX_DROP_MONITOR;
  613. }
  614. /* Check for weak IVs if possible */
  615. if (rx->sta && rx->key->conf.alg == ALG_WEP &&
  616. ieee80211_is_data(hdr->frame_control) &&
  617. (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
  618. !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
  619. ieee80211_wep_is_weak_iv(rx->skb, rx->key))
  620. rx->sta->wep_weak_iv_count++;
  621. switch (rx->key->conf.alg) {
  622. case ALG_WEP:
  623. result = ieee80211_crypto_wep_decrypt(rx);
  624. break;
  625. case ALG_TKIP:
  626. result = ieee80211_crypto_tkip_decrypt(rx);
  627. break;
  628. case ALG_CCMP:
  629. result = ieee80211_crypto_ccmp_decrypt(rx);
  630. break;
  631. case ALG_AES_CMAC:
  632. result = ieee80211_crypto_aes_cmac_decrypt(rx);
  633. break;
  634. }
  635. /* either the frame has been decrypted or will be dropped */
  636. rx->status->flag |= RX_FLAG_DECRYPTED;
  637. return result;
  638. }
  639. static ieee80211_rx_result debug_noinline
  640. ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
  641. {
  642. struct ieee80211_local *local;
  643. struct ieee80211_hdr *hdr;
  644. struct sk_buff *skb;
  645. local = rx->local;
  646. skb = rx->skb;
  647. hdr = (struct ieee80211_hdr *) skb->data;
  648. if (!local->pspolling)
  649. return RX_CONTINUE;
  650. if (!ieee80211_has_fromds(hdr->frame_control))
  651. /* this is not from AP */
  652. return RX_CONTINUE;
  653. if (!ieee80211_is_data(hdr->frame_control))
  654. return RX_CONTINUE;
  655. if (!ieee80211_has_moredata(hdr->frame_control)) {
  656. /* AP has no more frames buffered for us */
  657. local->pspolling = false;
  658. return RX_CONTINUE;
  659. }
  660. /* more data bit is set, let's request a new frame from the AP */
  661. ieee80211_send_pspoll(local, rx->sdata);
  662. return RX_CONTINUE;
  663. }
  664. static void ap_sta_ps_start(struct sta_info *sta)
  665. {
  666. struct ieee80211_sub_if_data *sdata = sta->sdata;
  667. struct ieee80211_local *local = sdata->local;
  668. atomic_inc(&sdata->bss->num_sta_ps);
  669. set_sta_flags(sta, WLAN_STA_PS);
  670. drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
  671. #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
  672. printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
  673. sdata->dev->name, sta->sta.addr, sta->sta.aid);
  674. #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
  675. }
  676. static int ap_sta_ps_end(struct sta_info *sta)
  677. {
  678. struct ieee80211_sub_if_data *sdata = sta->sdata;
  679. struct ieee80211_local *local = sdata->local;
  680. int sent, buffered;
  681. atomic_dec(&sdata->bss->num_sta_ps);
  682. clear_sta_flags(sta, WLAN_STA_PS);
  683. drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
  684. if (!skb_queue_empty(&sta->ps_tx_buf))
  685. sta_info_clear_tim_bit(sta);
  686. #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
  687. printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
  688. sdata->dev->name, sta->sta.addr, sta->sta.aid);
  689. #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
  690. /* Send all buffered frames to the station */
  691. sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
  692. buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf);
  693. sent += buffered;
  694. local->total_ps_buffered -= buffered;
  695. #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
  696. printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
  697. "since STA not sleeping anymore\n", sdata->dev->name,
  698. sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
  699. #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
  700. return sent;
  701. }
  702. static ieee80211_rx_result debug_noinline
  703. ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
  704. {
  705. struct sta_info *sta = rx->sta;
  706. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  707. if (!sta)
  708. return RX_CONTINUE;
  709. /*
  710. * Update last_rx only for IBSS packets which are for the current
  711. * BSSID to avoid keeping the current IBSS network alive in cases
  712. * where other STAs start using different BSSID.
  713. */
  714. if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
  715. u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
  716. NL80211_IFTYPE_ADHOC);
  717. if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
  718. sta->last_rx = jiffies;
  719. } else if (!is_multicast_ether_addr(hdr->addr1)) {
  720. /*
  721. * Mesh beacons will update last_rx when if they are found to
  722. * match the current local configuration when processed.
  723. */
  724. sta->last_rx = jiffies;
  725. }
  726. if (!(rx->flags & IEEE80211_RX_RA_MATCH))
  727. return RX_CONTINUE;
  728. if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
  729. ieee80211_sta_rx_notify(rx->sdata, hdr);
  730. sta->rx_fragments++;
  731. sta->rx_bytes += rx->skb->len;
  732. sta->last_signal = rx->status->signal;
  733. sta->last_qual = rx->status->qual;
  734. sta->last_noise = rx->status->noise;
  735. /*
  736. * Change STA power saving mode only at the end of a frame
  737. * exchange sequence.
  738. */
  739. if (!ieee80211_has_morefrags(hdr->frame_control) &&
  740. (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
  741. rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
  742. if (test_sta_flags(sta, WLAN_STA_PS)) {
  743. /*
  744. * Ignore doze->wake transitions that are
  745. * indicated by non-data frames, the standard
  746. * is unclear here, but for example going to
  747. * PS mode and then scanning would cause a
  748. * doze->wake transition for the probe request,
  749. * and that is clearly undesirable.
  750. */
  751. if (ieee80211_is_data(hdr->frame_control) &&
  752. !ieee80211_has_pm(hdr->frame_control))
  753. rx->sent_ps_buffered += ap_sta_ps_end(sta);
  754. } else {
  755. if (ieee80211_has_pm(hdr->frame_control))
  756. ap_sta_ps_start(sta);
  757. }
  758. }
  759. /* Drop data::nullfunc frames silently, since they are used only to
  760. * control station power saving mode. */
  761. if (ieee80211_is_nullfunc(hdr->frame_control)) {
  762. I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
  763. /* Update counter and free packet here to avoid counting this
  764. * as a dropped packed. */
  765. sta->rx_packets++;
  766. dev_kfree_skb(rx->skb);
  767. return RX_QUEUED;
  768. }
  769. return RX_CONTINUE;
  770. } /* ieee80211_rx_h_sta_process */
  771. static inline struct ieee80211_fragment_entry *
  772. ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
  773. unsigned int frag, unsigned int seq, int rx_queue,
  774. struct sk_buff **skb)
  775. {
  776. struct ieee80211_fragment_entry *entry;
  777. int idx;
  778. idx = sdata->fragment_next;
  779. entry = &sdata->fragments[sdata->fragment_next++];
  780. if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
  781. sdata->fragment_next = 0;
  782. if (!skb_queue_empty(&entry->skb_list)) {
  783. #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  784. struct ieee80211_hdr *hdr =
  785. (struct ieee80211_hdr *) entry->skb_list.next->data;
  786. printk(KERN_DEBUG "%s: RX reassembly removed oldest "
  787. "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
  788. "addr1=%pM addr2=%pM\n",
  789. sdata->dev->name, idx,
  790. jiffies - entry->first_frag_time, entry->seq,
  791. entry->last_frag, hdr->addr1, hdr->addr2);
  792. #endif
  793. __skb_queue_purge(&entry->skb_list);
  794. }
  795. __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
  796. *skb = NULL;
  797. entry->first_frag_time = jiffies;
  798. entry->seq = seq;
  799. entry->rx_queue = rx_queue;
  800. entry->last_frag = frag;
  801. entry->ccmp = 0;
  802. entry->extra_len = 0;
  803. return entry;
  804. }
  805. static inline struct ieee80211_fragment_entry *
  806. ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
  807. unsigned int frag, unsigned int seq,
  808. int rx_queue, struct ieee80211_hdr *hdr)
  809. {
  810. struct ieee80211_fragment_entry *entry;
  811. int i, idx;
  812. idx = sdata->fragment_next;
  813. for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
  814. struct ieee80211_hdr *f_hdr;
  815. idx--;
  816. if (idx < 0)
  817. idx = IEEE80211_FRAGMENT_MAX - 1;
  818. entry = &sdata->fragments[idx];
  819. if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
  820. entry->rx_queue != rx_queue ||
  821. entry->last_frag + 1 != frag)
  822. continue;
  823. f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
  824. /*
  825. * Check ftype and addresses are equal, else check next fragment
  826. */
  827. if (((hdr->frame_control ^ f_hdr->frame_control) &
  828. cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
  829. compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
  830. compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
  831. continue;
  832. if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
  833. __skb_queue_purge(&entry->skb_list);
  834. continue;
  835. }
  836. return entry;
  837. }
  838. return NULL;
  839. }
  840. static ieee80211_rx_result debug_noinline
  841. ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
  842. {
  843. struct ieee80211_hdr *hdr;
  844. u16 sc;
  845. __le16 fc;
  846. unsigned int frag, seq;
  847. struct ieee80211_fragment_entry *entry;
  848. struct sk_buff *skb;
  849. hdr = (struct ieee80211_hdr *)rx->skb->data;
  850. fc = hdr->frame_control;
  851. sc = le16_to_cpu(hdr->seq_ctrl);
  852. frag = sc & IEEE80211_SCTL_FRAG;
  853. if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
  854. (rx->skb)->len < 24 ||
  855. is_multicast_ether_addr(hdr->addr1))) {
  856. /* not fragmented */
  857. goto out;
  858. }
  859. I802_DEBUG_INC(rx->local->rx_handlers_fragments);
  860. seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
  861. if (frag == 0) {
  862. /* This is the first fragment of a new frame. */
  863. entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
  864. rx->queue, &(rx->skb));
  865. if (rx->key && rx->key->conf.alg == ALG_CCMP &&
  866. ieee80211_has_protected(fc)) {
  867. /* Store CCMP PN so that we can verify that the next
  868. * fragment has a sequential PN value. */
  869. entry->ccmp = 1;
  870. memcpy(entry->last_pn,
  871. rx->key->u.ccmp.rx_pn[rx->queue],
  872. CCMP_PN_LEN);
  873. }
  874. return RX_QUEUED;
  875. }
  876. /* This is a fragment for a frame that should already be pending in
  877. * fragment cache. Add this fragment to the end of the pending entry.
  878. */
  879. entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
  880. if (!entry) {
  881. I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
  882. return RX_DROP_MONITOR;
  883. }
  884. /* Verify that MPDUs within one MSDU have sequential PN values.
  885. * (IEEE 802.11i, 8.3.3.4.5) */
  886. if (entry->ccmp) {
  887. int i;
  888. u8 pn[CCMP_PN_LEN], *rpn;
  889. if (!rx->key || rx->key->conf.alg != ALG_CCMP)
  890. return RX_DROP_UNUSABLE;
  891. memcpy(pn, entry->last_pn, CCMP_PN_LEN);
  892. for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
  893. pn[i]++;
  894. if (pn[i])
  895. break;
  896. }
  897. rpn = rx->key->u.ccmp.rx_pn[rx->queue];
  898. if (memcmp(pn, rpn, CCMP_PN_LEN))
  899. return RX_DROP_UNUSABLE;
  900. memcpy(entry->last_pn, pn, CCMP_PN_LEN);
  901. }
  902. skb_pull(rx->skb, ieee80211_hdrlen(fc));
  903. __skb_queue_tail(&entry->skb_list, rx->skb);
  904. entry->last_frag = frag;
  905. entry->extra_len += rx->skb->len;
  906. if (ieee80211_has_morefrags(fc)) {
  907. rx->skb = NULL;
  908. return RX_QUEUED;
  909. }
  910. rx->skb = __skb_dequeue(&entry->skb_list);
  911. if (skb_tailroom(rx->skb) < entry->extra_len) {
  912. I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
  913. if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
  914. GFP_ATOMIC))) {
  915. I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
  916. __skb_queue_purge(&entry->skb_list);
  917. return RX_DROP_UNUSABLE;
  918. }
  919. }
  920. while ((skb = __skb_dequeue(&entry->skb_list))) {
  921. memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
  922. dev_kfree_skb(skb);
  923. }
  924. /* Complete frame has been reassembled - process it now */
  925. rx->flags |= IEEE80211_RX_FRAGMENTED;
  926. out:
  927. if (rx->sta)
  928. rx->sta->rx_packets++;
  929. if (is_multicast_ether_addr(hdr->addr1))
  930. rx->local->dot11MulticastReceivedFrameCount++;
  931. else
  932. ieee80211_led_rx(rx->local);
  933. return RX_CONTINUE;
  934. }
  935. static ieee80211_rx_result debug_noinline
  936. ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
  937. {
  938. struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
  939. struct sk_buff *skb;
  940. int no_pending_pkts;
  941. __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
  942. if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
  943. !(rx->flags & IEEE80211_RX_RA_MATCH)))
  944. return RX_CONTINUE;
  945. if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
  946. (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
  947. return RX_DROP_UNUSABLE;
  948. skb = skb_dequeue(&rx->sta->tx_filtered);
  949. if (!skb) {
  950. skb = skb_dequeue(&rx->sta->ps_tx_buf);
  951. if (skb)
  952. rx->local->total_ps_buffered--;
  953. }
  954. no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
  955. skb_queue_empty(&rx->sta->ps_tx_buf);
  956. if (skb) {
  957. struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  958. struct ieee80211_hdr *hdr =
  959. (struct ieee80211_hdr *) skb->data;
  960. /*
  961. * Tell TX path to send this frame even though the STA may
  962. * still remain is PS mode after this frame exchange.
  963. */
  964. info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
  965. #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
  966. printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
  967. rx->sta->sta.addr, rx->sta->sta.aid,
  968. skb_queue_len(&rx->sta->ps_tx_buf));
  969. #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
  970. /* Use MoreData flag to indicate whether there are more
  971. * buffered frames for this STA */
  972. if (no_pending_pkts)
  973. hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
  974. else
  975. hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
  976. ieee80211_add_pending_skb(rx->local, skb);
  977. if (no_pending_pkts)
  978. sta_info_clear_tim_bit(rx->sta);
  979. #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
  980. } else if (!rx->sent_ps_buffered) {
  981. /*
  982. * FIXME: This can be the result of a race condition between
  983. * us expiring a frame and the station polling for it.
  984. * Should we send it a null-func frame indicating we
  985. * have nothing buffered for it?
  986. */
  987. printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
  988. "though there are no buffered frames for it\n",
  989. rx->dev->name, rx->sta->sta.addr);
  990. #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
  991. }
  992. /* Free PS Poll skb here instead of returning RX_DROP that would
  993. * count as an dropped frame. */
  994. dev_kfree_skb(rx->skb);
  995. return RX_QUEUED;
  996. }
  997. static ieee80211_rx_result debug_noinline
  998. ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
  999. {
  1000. u8 *data = rx->skb->data;
  1001. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
  1002. if (!ieee80211_is_data_qos(hdr->frame_control))
  1003. return RX_CONTINUE;
  1004. /* remove the qos control field, update frame type and meta-data */
  1005. memmove(data + IEEE80211_QOS_CTL_LEN, data,
  1006. ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
  1007. hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
  1008. /* change frame type to non QOS */
  1009. hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
  1010. return RX_CONTINUE;
  1011. }
  1012. static int
  1013. ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
  1014. {
  1015. if (unlikely(!rx->sta ||
  1016. !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
  1017. return -EACCES;
  1018. return 0;
  1019. }
  1020. static int
  1021. ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
  1022. {
  1023. /*
  1024. * Pass through unencrypted frames if the hardware has
  1025. * decrypted them already.
  1026. */
  1027. if (rx->status->flag & RX_FLAG_DECRYPTED)
  1028. return 0;
  1029. /* Drop unencrypted frames if key is set. */
  1030. if (unlikely(!ieee80211_has_protected(fc) &&
  1031. !ieee80211_is_nullfunc(fc) &&
  1032. ieee80211_is_data(fc) &&
  1033. (rx->key || rx->sdata->drop_unencrypted)))
  1034. return -EACCES;
  1035. if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
  1036. if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
  1037. rx->key))
  1038. return -EACCES;
  1039. /* BIP does not use Protected field, so need to check MMIE */
  1040. if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
  1041. && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
  1042. rx->key))
  1043. return -EACCES;
  1044. /*
  1045. * When using MFP, Action frames are not allowed prior to
  1046. * having configured keys.
  1047. */
  1048. if (unlikely(ieee80211_is_action(fc) && !rx->key &&
  1049. ieee80211_is_robust_mgmt_frame(
  1050. (struct ieee80211_hdr *) rx->skb->data)))
  1051. return -EACCES;
  1052. }
  1053. return 0;
  1054. }
  1055. static int
  1056. __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
  1057. {
  1058. struct net_device *dev = rx->dev;
  1059. struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  1060. return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type);
  1061. }
  1062. /*
  1063. * requires that rx->skb is a frame with ethernet header
  1064. */
  1065. static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
  1066. {
  1067. static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
  1068. = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
  1069. struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
  1070. /*
  1071. * Allow EAPOL frames to us/the PAE group address regardless
  1072. * of whether the frame was encrypted or not.
  1073. */
  1074. if (ehdr->h_proto == htons(ETH_P_PAE) &&
  1075. (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
  1076. compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
  1077. return true;
  1078. if (ieee80211_802_1x_port_control(rx) ||
  1079. ieee80211_drop_unencrypted(rx, fc))
  1080. return false;
  1081. return true;
  1082. }
  1083. /*
  1084. * requires that rx->skb is a frame with ethernet header
  1085. */
  1086. static void
  1087. ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
  1088. {
  1089. struct net_device *dev = rx->dev;
  1090. struct ieee80211_local *local = rx->local;
  1091. struct sk_buff *skb, *xmit_skb;
  1092. struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  1093. struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
  1094. struct sta_info *dsta;
  1095. skb = rx->skb;
  1096. xmit_skb = NULL;
  1097. if ((sdata->vif.type == NL80211_IFTYPE_AP ||
  1098. sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
  1099. !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
  1100. (rx->flags & IEEE80211_RX_RA_MATCH)) {
  1101. if (is_multicast_ether_addr(ehdr->h_dest)) {
  1102. /*
  1103. * send multicast frames both to higher layers in
  1104. * local net stack and back to the wireless medium
  1105. */
  1106. xmit_skb = skb_copy(skb, GFP_ATOMIC);
  1107. if (!xmit_skb && net_ratelimit())
  1108. printk(KERN_DEBUG "%s: failed to clone "
  1109. "multicast frame\n", dev->name);
  1110. } else {
  1111. dsta = sta_info_get(local, skb->data);
  1112. if (dsta && dsta->sdata->dev == dev) {
  1113. /*
  1114. * The destination station is associated to
  1115. * this AP (in this VLAN), so send the frame
  1116. * directly to it and do not pass it to local
  1117. * net stack.
  1118. */
  1119. xmit_skb = skb;
  1120. skb = NULL;
  1121. }
  1122. }
  1123. }
  1124. if (skb) {
  1125. int align __maybe_unused;
  1126. #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  1127. /*
  1128. * 'align' will only take the values 0 or 2 here
  1129. * since all frames are required to be aligned
  1130. * to 2-byte boundaries when being passed to
  1131. * mac80211. That also explains the __skb_push()
  1132. * below.
  1133. */
  1134. align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
  1135. if (align) {
  1136. if (WARN_ON(skb_headroom(skb) < 3)) {
  1137. dev_kfree_skb(skb);
  1138. skb = NULL;
  1139. } else {
  1140. u8 *data = skb->data;
  1141. size_t len = skb->len;
  1142. u8 *new = __skb_push(skb, align);
  1143. memmove(new, data, len);
  1144. __skb_trim(skb, len);
  1145. }
  1146. }
  1147. #endif
  1148. if (skb) {
  1149. /* deliver to local stack */
  1150. skb->protocol = eth_type_trans(skb, dev);
  1151. memset(skb->cb, 0, sizeof(skb->cb));
  1152. netif_rx(skb);
  1153. }
  1154. }
  1155. if (xmit_skb) {
  1156. /* send to wireless media */
  1157. xmit_skb->protocol = htons(ETH_P_802_3);
  1158. skb_reset_network_header(xmit_skb);
  1159. skb_reset_mac_header(xmit_skb);
  1160. dev_queue_xmit(xmit_skb);
  1161. }
  1162. }
  1163. static ieee80211_rx_result debug_noinline
  1164. ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
  1165. {
  1166. struct net_device *dev = rx->dev;
  1167. struct ieee80211_local *local = rx->local;
  1168. u16 ethertype;
  1169. u8 *payload;
  1170. struct sk_buff *skb = rx->skb, *frame = NULL;
  1171. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  1172. __le16 fc = hdr->frame_control;
  1173. const struct ethhdr *eth;
  1174. int remaining, err;
  1175. u8 dst[ETH_ALEN];
  1176. u8 src[ETH_ALEN];
  1177. if (unlikely(!ieee80211_is_data(fc)))
  1178. return RX_CONTINUE;
  1179. if (unlikely(!ieee80211_is_data_present(fc)))
  1180. return RX_DROP_MONITOR;
  1181. if (!(rx->flags & IEEE80211_RX_AMSDU))
  1182. return RX_CONTINUE;
  1183. err = __ieee80211_data_to_8023(rx);
  1184. if (unlikely(err))
  1185. return RX_DROP_UNUSABLE;
  1186. skb->dev = dev;
  1187. dev->stats.rx_packets++;
  1188. dev->stats.rx_bytes += skb->len;
  1189. /* skip the wrapping header */
  1190. eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
  1191. if (!eth)
  1192. return RX_DROP_UNUSABLE;
  1193. while (skb != frame) {
  1194. u8 padding;
  1195. __be16 len = eth->h_proto;
  1196. unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
  1197. remaining = skb->len;
  1198. memcpy(dst, eth->h_dest, ETH_ALEN);
  1199. memcpy(src, eth->h_source, ETH_ALEN);
  1200. padding = ((4 - subframe_len) & 0x3);
  1201. /* the last MSDU has no padding */
  1202. if (subframe_len > remaining)
  1203. return RX_DROP_UNUSABLE;
  1204. skb_pull(skb, sizeof(struct ethhdr));
  1205. /* if last subframe reuse skb */
  1206. if (remaining <= subframe_len + padding)
  1207. frame = skb;
  1208. else {
  1209. /*
  1210. * Allocate and reserve two bytes more for payload
  1211. * alignment since sizeof(struct ethhdr) is 14.
  1212. */
  1213. frame = dev_alloc_skb(
  1214. ALIGN(local->hw.extra_tx_headroom, 4) +
  1215. subframe_len + 2);
  1216. if (frame == NULL)
  1217. return RX_DROP_UNUSABLE;
  1218. skb_reserve(frame,
  1219. ALIGN(local->hw.extra_tx_headroom, 4) +
  1220. sizeof(struct ethhdr) + 2);
  1221. memcpy(skb_put(frame, ntohs(len)), skb->data,
  1222. ntohs(len));
  1223. eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
  1224. padding);
  1225. if (!eth) {
  1226. dev_kfree_skb(frame);
  1227. return RX_DROP_UNUSABLE;
  1228. }
  1229. }
  1230. skb_reset_network_header(frame);
  1231. frame->dev = dev;
  1232. frame->priority = skb->priority;
  1233. rx->skb = frame;
  1234. payload = frame->data;
  1235. ethertype = (payload[6] << 8) | payload[7];
  1236. if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
  1237. ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
  1238. compare_ether_addr(payload,
  1239. bridge_tunnel_header) == 0)) {
  1240. /* remove RFC1042 or Bridge-Tunnel
  1241. * encapsulation and replace EtherType */
  1242. skb_pull(frame, 6);
  1243. memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
  1244. memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
  1245. } else {
  1246. memcpy(skb_push(frame, sizeof(__be16)),
  1247. &len, sizeof(__be16));
  1248. memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
  1249. memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
  1250. }
  1251. if (!ieee80211_frame_allowed(rx, fc)) {
  1252. if (skb == frame) /* last frame */
  1253. return RX_DROP_UNUSABLE;
  1254. dev_kfree_skb(frame);
  1255. continue;
  1256. }
  1257. ieee80211_deliver_skb(rx);
  1258. }
  1259. return RX_QUEUED;
  1260. }
  1261. #ifdef CONFIG_MAC80211_MESH
  1262. static ieee80211_rx_result
  1263. ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
  1264. {
  1265. struct ieee80211_hdr *hdr;
  1266. struct ieee80211s_hdr *mesh_hdr;
  1267. unsigned int hdrlen;
  1268. struct sk_buff *skb = rx->skb, *fwd_skb;
  1269. struct ieee80211_local *local = rx->local;
  1270. struct ieee80211_sub_if_data *sdata;
  1271. hdr = (struct ieee80211_hdr *) skb->data;
  1272. hdrlen = ieee80211_hdrlen(hdr->frame_control);
  1273. mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
  1274. sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
  1275. if (!ieee80211_is_data(hdr->frame_control))
  1276. return RX_CONTINUE;
  1277. if (!mesh_hdr->ttl)
  1278. /* illegal frame */
  1279. return RX_DROP_MONITOR;
  1280. if (!is_multicast_ether_addr(hdr->addr1) &&
  1281. (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6)) {
  1282. struct mesh_path *mppath;
  1283. rcu_read_lock();
  1284. mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
  1285. if (!mppath) {
  1286. mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
  1287. } else {
  1288. spin_lock_bh(&mppath->state_lock);
  1289. mppath->exp_time = jiffies;
  1290. if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
  1291. memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
  1292. spin_unlock_bh(&mppath->state_lock);
  1293. }
  1294. rcu_read_unlock();
  1295. }
  1296. /* Frame has reached destination. Don't forward */
  1297. if (!is_multicast_ether_addr(hdr->addr1) &&
  1298. compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
  1299. return RX_CONTINUE;
  1300. mesh_hdr->ttl--;
  1301. if (rx->flags & IEEE80211_RX_RA_MATCH) {
  1302. if (!mesh_hdr->ttl)
  1303. IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
  1304. dropped_frames_ttl);
  1305. else {
  1306. struct ieee80211_hdr *fwd_hdr;
  1307. struct ieee80211_tx_info *info;
  1308. fwd_skb = skb_copy(skb, GFP_ATOMIC);
  1309. if (!fwd_skb && net_ratelimit())
  1310. printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
  1311. rx->dev->name);
  1312. fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
  1313. memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
  1314. info = IEEE80211_SKB_CB(fwd_skb);
  1315. memset(info, 0, sizeof(*info));
  1316. info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
  1317. info->control.vif = &rx->sdata->vif;
  1318. ieee80211_select_queue(local, fwd_skb);
  1319. if (!is_multicast_ether_addr(fwd_hdr->addr1)) {
  1320. int err;
  1321. /*
  1322. * Save TA to addr1 to send TA a path error if a
  1323. * suitable next hop is not found
  1324. */
  1325. memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
  1326. ETH_ALEN);
  1327. err = mesh_nexthop_lookup(fwd_skb, sdata);
  1328. /* Failed to immediately resolve next hop:
  1329. * fwded frame was dropped or will be added
  1330. * later to the pending skb queue. */
  1331. if (err)
  1332. return RX_DROP_MONITOR;
  1333. }
  1334. IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
  1335. fwded_frames);
  1336. ieee80211_add_pending_skb(local, fwd_skb);
  1337. }
  1338. }
  1339. if (is_multicast_ether_addr(hdr->addr1) ||
  1340. rx->dev->flags & IFF_PROMISC)
  1341. return RX_CONTINUE;
  1342. else
  1343. return RX_DROP_MONITOR;
  1344. }
  1345. #endif
  1346. static ieee80211_rx_result debug_noinline
  1347. ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
  1348. {
  1349. struct net_device *dev = rx->dev;
  1350. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  1351. __le16 fc = hdr->frame_control;
  1352. int err;
  1353. if (unlikely(!ieee80211_is_data(hdr->frame_control)))
  1354. return RX_CONTINUE;
  1355. if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
  1356. return RX_DROP_MONITOR;
  1357. err = __ieee80211_data_to_8023(rx);
  1358. if (unlikely(err))
  1359. return RX_DROP_UNUSABLE;
  1360. if (!ieee80211_frame_allowed(rx, fc))
  1361. return RX_DROP_MONITOR;
  1362. rx->skb->dev = dev;
  1363. dev->stats.rx_packets++;
  1364. dev->stats.rx_bytes += rx->skb->len;
  1365. ieee80211_deliver_skb(rx);
  1366. return RX_QUEUED;
  1367. }
  1368. static ieee80211_rx_result debug_noinline
  1369. ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
  1370. {
  1371. struct ieee80211_local *local = rx->local;
  1372. struct ieee80211_hw *hw = &local->hw;
  1373. struct sk_buff *skb = rx->skb;
  1374. struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
  1375. struct tid_ampdu_rx *tid_agg_rx;
  1376. u16 start_seq_num;
  1377. u16 tid;
  1378. if (likely(!ieee80211_is_ctl(bar->frame_control)))
  1379. return RX_CONTINUE;
  1380. if (ieee80211_is_back_req(bar->frame_control)) {
  1381. if (!rx->sta)
  1382. return RX_CONTINUE;
  1383. tid = le16_to_cpu(bar->control) >> 12;
  1384. if (rx->sta->ampdu_mlme.tid_state_rx[tid]
  1385. != HT_AGG_STATE_OPERATIONAL)
  1386. return RX_CONTINUE;
  1387. tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
  1388. start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
  1389. /* reset session timer */
  1390. if (tid_agg_rx->timeout)
  1391. mod_timer(&tid_agg_rx->session_timer,
  1392. TU_TO_EXP_TIME(tid_agg_rx->timeout));
  1393. /* manage reordering buffer according to requested */
  1394. /* sequence number */
  1395. rcu_read_lock();
  1396. ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
  1397. start_seq_num, 1);
  1398. rcu_read_unlock();
  1399. return RX_DROP_UNUSABLE;
  1400. }
  1401. return RX_CONTINUE;
  1402. }
  1403. static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
  1404. struct ieee80211_mgmt *mgmt,
  1405. size_t len)
  1406. {
  1407. struct ieee80211_local *local = sdata->local;
  1408. struct sk_buff *skb;
  1409. struct ieee80211_mgmt *resp;
  1410. if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
  1411. /* Not to own unicast address */
  1412. return;
  1413. }
  1414. if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
  1415. compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
  1416. /* Not from the current AP or not associated yet. */
  1417. return;
  1418. }
  1419. if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
  1420. /* Too short SA Query request frame */
  1421. return;
  1422. }
  1423. skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
  1424. if (skb == NULL)
  1425. return;
  1426. skb_reserve(skb, local->hw.extra_tx_headroom);
  1427. resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
  1428. memset(resp, 0, 24);
  1429. memcpy(resp->da, mgmt->sa, ETH_ALEN);
  1430. memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
  1431. memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
  1432. resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  1433. IEEE80211_STYPE_ACTION);
  1434. skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
  1435. resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
  1436. resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
  1437. memcpy(resp->u.action.u.sa_query.trans_id,
  1438. mgmt->u.action.u.sa_query.trans_id,
  1439. WLAN_SA_QUERY_TR_ID_LEN);
  1440. ieee80211_tx_skb(sdata, skb, 1);
  1441. }
  1442. static ieee80211_rx_result debug_noinline
  1443. ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
  1444. {
  1445. struct ieee80211_local *local = rx->local;
  1446. struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
  1447. struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  1448. int len = rx->skb->len;
  1449. if (!ieee80211_is_action(mgmt->frame_control))
  1450. return RX_CONTINUE;
  1451. if (!rx->sta)
  1452. return RX_DROP_MONITOR;
  1453. if (!(rx->flags & IEEE80211_RX_RA_MATCH))
  1454. return RX_DROP_MONITOR;
  1455. if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
  1456. return RX_DROP_MONITOR;
  1457. /* all categories we currently handle have action_code */
  1458. if (len < IEEE80211_MIN_ACTION_SIZE + 1)
  1459. return RX_DROP_MONITOR;
  1460. switch (mgmt->u.action.category) {
  1461. case WLAN_CATEGORY_BACK:
  1462. /*
  1463. * The aggregation code is not prepared to handle
  1464. * anything but STA/AP due to the BSSID handling;
  1465. * IBSS could work in the code but isn't supported
  1466. * by drivers or the standard.
  1467. */
  1468. if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  1469. sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
  1470. sdata->vif.type != NL80211_IFTYPE_AP)
  1471. return RX_DROP_MONITOR;
  1472. switch (mgmt->u.action.u.addba_req.action_code) {
  1473. case WLAN_ACTION_ADDBA_REQ:
  1474. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1475. sizeof(mgmt->u.action.u.addba_req)))
  1476. return RX_DROP_MONITOR;
  1477. ieee80211_process_addba_request(local, rx->sta, mgmt, len);
  1478. break;
  1479. case WLAN_ACTION_ADDBA_RESP:
  1480. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1481. sizeof(mgmt->u.action.u.addba_resp)))
  1482. return RX_DROP_MONITOR;
  1483. ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
  1484. break;
  1485. case WLAN_ACTION_DELBA:
  1486. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1487. sizeof(mgmt->u.action.u.delba)))
  1488. return RX_DROP_MONITOR;
  1489. ieee80211_process_delba(sdata, rx->sta, mgmt, len);
  1490. break;
  1491. }
  1492. break;
  1493. case WLAN_CATEGORY_SPECTRUM_MGMT:
  1494. if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
  1495. return RX_DROP_MONITOR;
  1496. if (sdata->vif.type != NL80211_IFTYPE_STATION)
  1497. return RX_DROP_MONITOR;
  1498. switch (mgmt->u.action.u.measurement.action_code) {
  1499. case WLAN_ACTION_SPCT_MSR_REQ:
  1500. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1501. sizeof(mgmt->u.action.u.measurement)))
  1502. return RX_DROP_MONITOR;
  1503. ieee80211_process_measurement_req(sdata, mgmt, len);
  1504. break;
  1505. case WLAN_ACTION_SPCT_CHL_SWITCH:
  1506. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1507. sizeof(mgmt->u.action.u.chan_switch)))
  1508. return RX_DROP_MONITOR;
  1509. if (sdata->vif.type != NL80211_IFTYPE_STATION)
  1510. return RX_DROP_MONITOR;
  1511. if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
  1512. return RX_DROP_MONITOR;
  1513. return ieee80211_sta_rx_mgmt(sdata, rx->skb);
  1514. }
  1515. break;
  1516. case WLAN_CATEGORY_SA_QUERY:
  1517. if (len < (IEEE80211_MIN_ACTION_SIZE +
  1518. sizeof(mgmt->u.action.u.sa_query)))
  1519. return RX_DROP_MONITOR;
  1520. switch (mgmt->u.action.u.sa_query.action) {
  1521. case WLAN_ACTION_SA_QUERY_REQUEST:
  1522. if (sdata->vif.type != NL80211_IFTYPE_STATION)
  1523. return RX_DROP_MONITOR;
  1524. ieee80211_process_sa_query_req(sdata, mgmt, len);
  1525. break;
  1526. case WLAN_ACTION_SA_QUERY_RESPONSE:
  1527. /*
  1528. * SA Query response is currently only used in AP mode
  1529. * and it is processed in user space.
  1530. */
  1531. return RX_CONTINUE;
  1532. }
  1533. break;
  1534. default:
  1535. return RX_CONTINUE;
  1536. }
  1537. rx->sta->rx_packets++;
  1538. dev_kfree_skb(rx->skb);
  1539. return RX_QUEUED;
  1540. }
  1541. static ieee80211_rx_result debug_noinline
  1542. ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
  1543. {
  1544. struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
  1545. struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  1546. if (!(rx->flags & IEEE80211_RX_RA_MATCH))
  1547. return RX_DROP_MONITOR;
  1548. if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
  1549. return RX_DROP_MONITOR;
  1550. if (ieee80211_vif_is_mesh(&sdata->vif))
  1551. return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
  1552. if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
  1553. return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
  1554. if (sdata->vif.type == NL80211_IFTYPE_STATION)
  1555. return ieee80211_sta_rx_mgmt(sdata, rx->skb);
  1556. return RX_DROP_MONITOR;
  1557. }
  1558. static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
  1559. struct ieee80211_rx_data *rx)
  1560. {
  1561. int keyidx;
  1562. unsigned int hdrlen;
  1563. hdrlen = ieee80211_hdrlen(hdr->frame_control);
  1564. if (rx->skb->len >= hdrlen + 4)
  1565. keyidx = rx->skb->data[hdrlen + 3] >> 6;
  1566. else
  1567. keyidx = -1;
  1568. if (!rx->sta) {
  1569. /*
  1570. * Some hardware seem to generate incorrect Michael MIC
  1571. * reports; ignore them to avoid triggering countermeasures.
  1572. */
  1573. goto ignore;
  1574. }
  1575. if (!ieee80211_has_protected(hdr->frame_control))
  1576. goto ignore;
  1577. if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
  1578. /*
  1579. * APs with pairwise keys should never receive Michael MIC
  1580. * errors for non-zero keyidx because these are reserved for
  1581. * group keys and only the AP is sending real multicast
  1582. * frames in the BSS.
  1583. */
  1584. goto ignore;
  1585. }
  1586. if (!ieee80211_is_data(hdr->frame_control) &&
  1587. !ieee80211_is_auth(hdr->frame_control))
  1588. goto ignore;
  1589. mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
  1590. GFP_ATOMIC);
  1591. ignore:
  1592. dev_kfree_skb(rx->skb);
  1593. rx->skb = NULL;
  1594. }
  1595. /* TODO: use IEEE80211_RX_FRAGMENTED */
  1596. static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
  1597. {
  1598. struct ieee80211_sub_if_data *sdata;
  1599. struct ieee80211_local *local = rx->local;
  1600. struct ieee80211_rtap_hdr {
  1601. struct ieee80211_radiotap_header hdr;
  1602. u8 flags;
  1603. u8 rate;
  1604. __le16 chan_freq;
  1605. __le16 chan_flags;
  1606. } __attribute__ ((packed)) *rthdr;
  1607. struct sk_buff *skb = rx->skb, *skb2;
  1608. struct net_device *prev_dev = NULL;
  1609. struct ieee80211_rx_status *status = rx->status;
  1610. if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
  1611. goto out_free_skb;
  1612. if (skb_headroom(skb) < sizeof(*rthdr) &&
  1613. pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
  1614. goto out_free_skb;
  1615. rthdr = (void *)skb_push(skb, sizeof(*rthdr));
  1616. memset(rthdr, 0, sizeof(*rthdr));
  1617. rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
  1618. rthdr->hdr.it_present =
  1619. cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
  1620. (1 << IEEE80211_RADIOTAP_RATE) |
  1621. (1 << IEEE80211_RADIOTAP_CHANNEL));
  1622. rthdr->rate = rx->rate->bitrate / 5;
  1623. rthdr->chan_freq = cpu_to_le16(status->freq);
  1624. if (status->band == IEEE80211_BAND_5GHZ)
  1625. rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
  1626. IEEE80211_CHAN_5GHZ);
  1627. else
  1628. rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
  1629. IEEE80211_CHAN_2GHZ);
  1630. skb_set_mac_header(skb, 0);
  1631. skb->ip_summed = CHECKSUM_UNNECESSARY;
  1632. skb->pkt_type = PACKET_OTHERHOST;
  1633. skb->protocol = htons(ETH_P_802_2);
  1634. list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  1635. if (!netif_running(sdata->dev))
  1636. continue;
  1637. if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
  1638. !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
  1639. continue;
  1640. if (prev_dev) {
  1641. skb2 = skb_clone(skb, GFP_ATOMIC);
  1642. if (skb2) {
  1643. skb2->dev = prev_dev;
  1644. netif_rx(skb2);
  1645. }
  1646. }
  1647. prev_dev = sdata->dev;
  1648. sdata->dev->stats.rx_packets++;
  1649. sdata->dev->stats.rx_bytes += skb->len;
  1650. }
  1651. if (prev_dev) {
  1652. skb->dev = prev_dev;
  1653. netif_rx(skb);
  1654. skb = NULL;
  1655. } else
  1656. goto out_free_skb;
  1657. rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
  1658. return;
  1659. out_free_skb:
  1660. dev_kfree_skb(skb);
  1661. }
  1662. static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
  1663. struct ieee80211_rx_data *rx,
  1664. struct sk_buff *skb)
  1665. {
  1666. ieee80211_rx_result res = RX_DROP_MONITOR;
  1667. rx->skb = skb;
  1668. rx->sdata = sdata;
  1669. rx->dev = sdata->dev;
  1670. #define CALL_RXH(rxh) \
  1671. do { \
  1672. res = rxh(rx); \
  1673. if (res != RX_CONTINUE) \
  1674. goto rxh_done; \
  1675. } while (0);
  1676. CALL_RXH(ieee80211_rx_h_passive_scan)
  1677. CALL_RXH(ieee80211_rx_h_check)
  1678. CALL_RXH(ieee80211_rx_h_decrypt)
  1679. CALL_RXH(ieee80211_rx_h_check_more_data)
  1680. CALL_RXH(ieee80211_rx_h_sta_process)
  1681. CALL_RXH(ieee80211_rx_h_defragment)
  1682. CALL_RXH(ieee80211_rx_h_ps_poll)
  1683. CALL_RXH(ieee80211_rx_h_michael_mic_verify)
  1684. /* must be after MMIC verify so header is counted in MPDU mic */
  1685. CALL_RXH(ieee80211_rx_h_remove_qos_control)
  1686. CALL_RXH(ieee80211_rx_h_amsdu)
  1687. #ifdef CONFIG_MAC80211_MESH
  1688. if (ieee80211_vif_is_mesh(&sdata->vif))
  1689. CALL_RXH(ieee80211_rx_h_mesh_fwding);
  1690. #endif
  1691. CALL_RXH(ieee80211_rx_h_data)
  1692. CALL_RXH(ieee80211_rx_h_ctrl)
  1693. CALL_RXH(ieee80211_rx_h_action)
  1694. CALL_RXH(ieee80211_rx_h_mgmt)
  1695. #undef CALL_RXH
  1696. rxh_done:
  1697. switch (res) {
  1698. case RX_DROP_MONITOR:
  1699. I802_DEBUG_INC(sdata->local->rx_handlers_drop);
  1700. if (rx->sta)
  1701. rx->sta->rx_dropped++;
  1702. /* fall through */
  1703. case RX_CONTINUE:
  1704. ieee80211_rx_cooked_monitor(rx);
  1705. break;
  1706. case RX_DROP_UNUSABLE:
  1707. I802_DEBUG_INC(sdata->local->rx_handlers_drop);
  1708. if (rx->sta)
  1709. rx->sta->rx_dropped++;
  1710. dev_kfree_skb(rx->skb);
  1711. break;
  1712. case RX_QUEUED:
  1713. I802_DEBUG_INC(sdata->local->rx_handlers_queued);
  1714. break;
  1715. }
  1716. }
  1717. /* main receive path */
  1718. static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
  1719. struct ieee80211_rx_data *rx,
  1720. struct ieee80211_hdr *hdr)
  1721. {
  1722. u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
  1723. int multicast = is_multicast_ether_addr(hdr->addr1);
  1724. switch (sdata->vif.type) {
  1725. case NL80211_IFTYPE_STATION:
  1726. if (!bssid)
  1727. return 0;
  1728. if (!multicast &&
  1729. compare_ether_addr(sdata->dev->dev_addr, hdr->addr1) != 0) {
  1730. if (!(sdata->dev->flags & IFF_PROMISC))
  1731. return 0;
  1732. rx->flags &= ~IEEE80211_RX_RA_MATCH;
  1733. }
  1734. break;
  1735. case NL80211_IFTYPE_ADHOC:
  1736. if (!bssid)
  1737. return 0;
  1738. if (ieee80211_is_beacon(hdr->frame_control)) {
  1739. return 1;
  1740. }
  1741. else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
  1742. if (!(rx->flags & IEEE80211_RX_IN_SCAN))
  1743. return 0;
  1744. rx->flags &= ~IEEE80211_RX_RA_MATCH;
  1745. } else if (!multicast &&
  1746. compare_ether_addr(sdata->dev->dev_addr,
  1747. hdr->addr1) != 0) {
  1748. if (!(sdata->dev->flags & IFF_PROMISC))
  1749. return 0;
  1750. rx->flags &= ~IEEE80211_RX_RA_MATCH;
  1751. } else if (!rx->sta) {
  1752. int rate_idx;
  1753. if (rx->status->flag & RX_FLAG_HT)
  1754. rate_idx = 0; /* TODO: HT rates */
  1755. else
  1756. rate_idx = rx->status->rate_idx;
  1757. rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
  1758. BIT(rate_idx));
  1759. }
  1760. break;
  1761. case NL80211_IFTYPE_MESH_POINT:
  1762. if (!multicast &&
  1763. compare_ether_addr(sdata->dev->dev_addr,
  1764. hdr->addr1) != 0) {
  1765. if (!(sdata->dev->flags & IFF_PROMISC))
  1766. return 0;
  1767. rx->flags &= ~IEEE80211_RX_RA_MATCH;
  1768. }
  1769. break;
  1770. case NL80211_IFTYPE_AP_VLAN:
  1771. case NL80211_IFTYPE_AP:
  1772. if (!bssid) {
  1773. if (compare_ether_addr(sdata->dev->dev_addr,
  1774. hdr->addr1))
  1775. return 0;
  1776. } else if (!ieee80211_bssid_match(bssid,
  1777. sdata->dev->dev_addr)) {
  1778. if (!(rx->flags & IEEE80211_RX_IN_SCAN))
  1779. return 0;
  1780. rx->flags &= ~IEEE80211_RX_RA_MATCH;
  1781. }
  1782. break;
  1783. case NL80211_IFTYPE_WDS:
  1784. if (bssid || !ieee80211_is_data(hdr->frame_control))
  1785. return 0;
  1786. if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
  1787. return 0;
  1788. break;
  1789. case NL80211_IFTYPE_MONITOR:
  1790. /* take everything */
  1791. break;
  1792. case NL80211_IFTYPE_UNSPECIFIED:
  1793. case __NL80211_IFTYPE_AFTER_LAST:
  1794. /* should never get here */
  1795. WARN_ON(1);
  1796. break;
  1797. }
  1798. return 1;
  1799. }
  1800. /*
  1801. * This is the actual Rx frames handler. as it blongs to Rx path it must
  1802. * be called with rcu_read_lock protection.
  1803. */
  1804. static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
  1805. struct sk_buff *skb,
  1806. struct ieee80211_rate *rate)
  1807. {
  1808. struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  1809. struct ieee80211_local *local = hw_to_local(hw);
  1810. struct ieee80211_sub_if_data *sdata;
  1811. struct ieee80211_hdr *hdr;
  1812. struct ieee80211_rx_data rx;
  1813. int prepares;
  1814. struct ieee80211_sub_if_data *prev = NULL;
  1815. struct sk_buff *skb_new;
  1816. hdr = (struct ieee80211_hdr *)skb->data;
  1817. memset(&rx, 0, sizeof(rx));
  1818. rx.skb = skb;
  1819. rx.local = local;
  1820. rx.status = status;
  1821. rx.rate = rate;
  1822. if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
  1823. local->dot11ReceivedFragmentCount++;
  1824. rx.sta = sta_info_get(local, hdr->addr2);
  1825. if (rx.sta) {
  1826. rx.sdata = rx.sta->sdata;
  1827. rx.dev = rx.sta->sdata->dev;
  1828. }
  1829. if ((status->flag & RX_FLAG_MMIC_ERROR)) {
  1830. ieee80211_rx_michael_mic_report(hdr, &rx);
  1831. return;
  1832. }
  1833. if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
  1834. test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
  1835. rx.flags |= IEEE80211_RX_IN_SCAN;
  1836. ieee80211_parse_qos(&rx);
  1837. ieee80211_verify_alignment(&rx);
  1838. skb = rx.skb;
  1839. list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  1840. if (!netif_running(sdata->dev))
  1841. continue;
  1842. if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
  1843. continue;
  1844. rx.flags |= IEEE80211_RX_RA_MATCH;
  1845. prepares = prepare_for_handlers(sdata, &rx, hdr);
  1846. if (!prepares)
  1847. continue;
  1848. /*
  1849. * frame is destined for this interface, but if it's not
  1850. * also for the previous one we handle that after the
  1851. * loop to avoid copying the SKB once too much
  1852. */
  1853. if (!prev) {
  1854. prev = sdata;
  1855. continue;
  1856. }
  1857. /*
  1858. * frame was destined for the previous interface
  1859. * so invoke RX handlers for it
  1860. */
  1861. skb_new = skb_copy(skb, GFP_ATOMIC);
  1862. if (!skb_new) {
  1863. if (net_ratelimit())
  1864. printk(KERN_DEBUG "%s: failed to copy "
  1865. "multicast frame for %s\n",
  1866. wiphy_name(local->hw.wiphy),
  1867. prev->dev->name);
  1868. continue;
  1869. }
  1870. ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
  1871. prev = sdata;
  1872. }
  1873. if (prev)
  1874. ieee80211_invoke_rx_handlers(prev, &rx, skb);
  1875. else
  1876. dev_kfree_skb(skb);
  1877. }
  1878. #define SEQ_MODULO 0x1000
  1879. #define SEQ_MASK 0xfff
  1880. static inline int seq_less(u16 sq1, u16 sq2)
  1881. {
  1882. return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
  1883. }
  1884. static inline u16 seq_inc(u16 sq)
  1885. {
  1886. return (sq + 1) & SEQ_MASK;
  1887. }
  1888. static inline u16 seq_sub(u16 sq1, u16 sq2)
  1889. {
  1890. return (sq1 - sq2) & SEQ_MASK;
  1891. }
  1892. static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
  1893. struct tid_ampdu_rx *tid_agg_rx,
  1894. int index)
  1895. {
  1896. struct ieee80211_supported_band *sband;
  1897. struct ieee80211_rate *rate;
  1898. struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
  1899. struct ieee80211_rx_status *status;
  1900. if (!skb)
  1901. goto no_frame;
  1902. status = IEEE80211_SKB_RXCB(skb);
  1903. /* release the reordered frames to stack */
  1904. sband = hw->wiphy->bands[status->band];
  1905. if (status->flag & RX_FLAG_HT)
  1906. rate = sband->bitrates; /* TODO: HT rates */
  1907. else
  1908. rate = &sband->bitrates[status->rate_idx];
  1909. __ieee80211_rx_handle_packet(hw, skb, rate);
  1910. tid_agg_rx->stored_mpdu_num--;
  1911. tid_agg_rx->reorder_buf[index] = NULL;
  1912. no_frame:
  1913. tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
  1914. }
  1915. /*
  1916. * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
  1917. * the skb was added to the buffer longer than this time ago, the earlier
  1918. * frames that have not yet been received are assumed to be lost and the skb
  1919. * can be released for processing. This may also release other skb's from the
  1920. * reorder buffer if there are no additional gaps between the frames.
  1921. */
  1922. #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
  1923. /*
  1924. * As it function blongs to Rx path it must be called with
  1925. * the proper rcu_read_lock protection for its flow.
  1926. */
  1927. static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  1928. struct tid_ampdu_rx *tid_agg_rx,
  1929. struct sk_buff *skb,
  1930. u16 mpdu_seq_num,
  1931. int bar_req)
  1932. {
  1933. u16 head_seq_num, buf_size;
  1934. int index;
  1935. buf_size = tid_agg_rx->buf_size;
  1936. head_seq_num = tid_agg_rx->head_seq_num;
  1937. /* frame with out of date sequence number */
  1938. if (seq_less(mpdu_seq_num, head_seq_num)) {
  1939. dev_kfree_skb(skb);
  1940. return 1;
  1941. }
  1942. /* if frame sequence number exceeds our buffering window size or
  1943. * block Ack Request arrived - release stored frames */
  1944. if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
  1945. /* new head to the ordering buffer */
  1946. if (bar_req)
  1947. head_seq_num = mpdu_seq_num;
  1948. else
  1949. head_seq_num =
  1950. seq_inc(seq_sub(mpdu_seq_num, buf_size));
  1951. /* release stored frames up to new head to stack */
  1952. while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
  1953. index = seq_sub(tid_agg_rx->head_seq_num,
  1954. tid_agg_rx->ssn)
  1955. % tid_agg_rx->buf_size;
  1956. ieee80211_release_reorder_frame(hw, tid_agg_rx,
  1957. index);
  1958. }
  1959. if (bar_req)
  1960. return 1;
  1961. }
  1962. /* now the new frame is always in the range of the reordering */
  1963. /* buffer window */
  1964. index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
  1965. % tid_agg_rx->buf_size;
  1966. /* check if we already stored this frame */
  1967. if (tid_agg_rx->reorder_buf[index]) {
  1968. dev_kfree_skb(skb);
  1969. return 1;
  1970. }
  1971. /* if arrived mpdu is in the right order and nothing else stored */
  1972. /* release it immediately */
  1973. if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
  1974. tid_agg_rx->stored_mpdu_num == 0) {
  1975. tid_agg_rx->head_seq_num =
  1976. seq_inc(tid_agg_rx->head_seq_num);
  1977. return 0;
  1978. }
  1979. /* put the frame in the reordering buffer */
  1980. tid_agg_rx->reorder_buf[index] = skb;
  1981. tid_agg_rx->reorder_time[index] = jiffies;
  1982. tid_agg_rx->stored_mpdu_num++;
  1983. /* release the buffer until next missing frame */
  1984. index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
  1985. % tid_agg_rx->buf_size;
  1986. if (!tid_agg_rx->reorder_buf[index] &&
  1987. tid_agg_rx->stored_mpdu_num > 1) {
  1988. /*
  1989. * No buffers ready to be released, but check whether any
  1990. * frames in the reorder buffer have timed out.
  1991. */
  1992. int j;
  1993. int skipped = 1;
  1994. for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
  1995. j = (j + 1) % tid_agg_rx->buf_size) {
  1996. if (tid_agg_rx->reorder_buf[j] == NULL) {
  1997. skipped++;
  1998. continue;
  1999. }
  2000. if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
  2001. HZ / 10))
  2002. break;
  2003. #ifdef CONFIG_MAC80211_HT_DEBUG
  2004. if (net_ratelimit())
  2005. printk(KERN_DEBUG "%s: release an RX reorder "
  2006. "frame due to timeout on earlier "
  2007. "frames\n",
  2008. wiphy_name(hw->wiphy));
  2009. #endif
  2010. ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
  2011. /*
  2012. * Increment the head seq# also for the skipped slots.
  2013. */
  2014. tid_agg_rx->head_seq_num =
  2015. (tid_agg_rx->head_seq_num + skipped) &
  2016. SEQ_MASK;
  2017. skipped = 0;
  2018. }
  2019. } else while (tid_agg_rx->reorder_buf[index]) {
  2020. ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
  2021. index = seq_sub(tid_agg_rx->head_seq_num,
  2022. tid_agg_rx->ssn) % tid_agg_rx->buf_size;
  2023. }
  2024. return 1;
  2025. }
  2026. static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
  2027. struct sk_buff *skb)
  2028. {
  2029. struct ieee80211_hw *hw = &local->hw;
  2030. struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  2031. struct sta_info *sta;
  2032. struct tid_ampdu_rx *tid_agg_rx;
  2033. u16 sc;
  2034. u16 mpdu_seq_num;
  2035. u8 ret = 0;
  2036. int tid;
  2037. sta = sta_info_get(local, hdr->addr2);
  2038. if (!sta)
  2039. return ret;
  2040. /* filter the QoS data rx stream according to
  2041. * STA/TID and check if this STA/TID is on aggregation */
  2042. if (!ieee80211_is_data_qos(hdr->frame_control))
  2043. goto end_reorder;
  2044. tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
  2045. if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
  2046. goto end_reorder;
  2047. tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
  2048. /* qos null data frames are excluded */
  2049. if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
  2050. goto end_reorder;
  2051. /* new un-ordered ampdu frame - process it */
  2052. /* reset session timer */
  2053. if (tid_agg_rx->timeout)
  2054. mod_timer(&tid_agg_rx->session_timer,
  2055. TU_TO_EXP_TIME(tid_agg_rx->timeout));
  2056. /* if this mpdu is fragmented - terminate rx aggregation session */
  2057. sc = le16_to_cpu(hdr->seq_ctrl);
  2058. if (sc & IEEE80211_SCTL_FRAG) {
  2059. ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
  2060. tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
  2061. ret = 1;
  2062. goto end_reorder;
  2063. }
  2064. /* according to mpdu sequence number deal with reordering buffer */
  2065. mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
  2066. ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
  2067. mpdu_seq_num, 0);
  2068. end_reorder:
  2069. return ret;
  2070. }
  2071. /*
  2072. * This is the receive path handler. It is called by a low level driver when an
  2073. * 802.11 MPDU is received from the hardware.
  2074. */
  2075. void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
  2076. {
  2077. struct ieee80211_local *local = hw_to_local(hw);
  2078. struct ieee80211_rate *rate = NULL;
  2079. struct ieee80211_supported_band *sband;
  2080. struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  2081. if (status->band < 0 ||
  2082. status->band >= IEEE80211_NUM_BANDS) {
  2083. WARN_ON(1);
  2084. return;
  2085. }
  2086. sband = local->hw.wiphy->bands[status->band];
  2087. if (!sband) {
  2088. WARN_ON(1);
  2089. return;
  2090. }
  2091. /*
  2092. * If we're suspending, it is possible although not too likely
  2093. * that we'd be receiving frames after having already partially
  2094. * quiesced the stack. We can't process such frames then since
  2095. * that might, for example, cause stations to be added or other
  2096. * driver callbacks be invoked.
  2097. */
  2098. if (unlikely(local->quiescing || local->suspended)) {
  2099. kfree_skb(skb);
  2100. return;
  2101. }
  2102. if (status->flag & RX_FLAG_HT) {
  2103. /* rate_idx is MCS index */
  2104. if (WARN_ON(status->rate_idx < 0 ||
  2105. status->rate_idx >= 76))
  2106. return;
  2107. /* HT rates are not in the table - use the highest legacy rate
  2108. * for now since other parts of mac80211 may not yet be fully
  2109. * MCS aware. */
  2110. rate = &sband->bitrates[sband->n_bitrates - 1];
  2111. } else {
  2112. if (WARN_ON(status->rate_idx < 0 ||
  2113. status->rate_idx >= sband->n_bitrates))
  2114. return;
  2115. rate = &sband->bitrates[status->rate_idx];
  2116. }
  2117. /*
  2118. * key references and virtual interfaces are protected using RCU
  2119. * and this requires that we are in a read-side RCU section during
  2120. * receive processing
  2121. */
  2122. rcu_read_lock();
  2123. /*
  2124. * Frames with failed FCS/PLCP checksum are not returned,
  2125. * all other frames are returned without radiotap header
  2126. * if it was previously present.
  2127. * Also, frames with less than 16 bytes are dropped.
  2128. */
  2129. skb = ieee80211_rx_monitor(local, skb, rate);
  2130. if (!skb) {
  2131. rcu_read_unlock();
  2132. return;
  2133. }
  2134. /*
  2135. * In theory, the block ack reordering should happen after duplicate
  2136. * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
  2137. * the call to ieee80211_rx_reorder_ampdu() should really be moved to
  2138. * happen as a new RX handler between ieee80211_rx_h_check and
  2139. * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
  2140. * the time being, the call can be here since RX reorder buf processing
  2141. * will implicitly skip duplicates. We could, in theory at least,
  2142. * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
  2143. * frames from other than operational channel), but that should not
  2144. * happen in normal networks.
  2145. */
  2146. if (!ieee80211_rx_reorder_ampdu(local, skb))
  2147. __ieee80211_rx_handle_packet(hw, skb, rate);
  2148. rcu_read_unlock();
  2149. }
  2150. EXPORT_SYMBOL(__ieee80211_rx);
  2151. /* This is a version of the rx handler that can be called from hard irq
  2152. * context. Post the skb on the queue and schedule the tasklet */
  2153. void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
  2154. {
  2155. struct ieee80211_local *local = hw_to_local(hw);
  2156. BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
  2157. skb->pkt_type = IEEE80211_RX_MSG;
  2158. skb_queue_tail(&local->skb_queue, skb);
  2159. tasklet_schedule(&local->tasklet);
  2160. }
  2161. EXPORT_SYMBOL(ieee80211_rx_irqsafe);