1 #include <linux/etherdevice.h>
2 #include <net/lib80211.h>
3
4 #include "hostap_80211.h"
5 #include "hostap.h"
6 #include "hostap_ap.h"
7
8 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
9 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
10 static unsigned char rfc1042_header[] =
11 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
12 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
13 static unsigned char bridge_tunnel_header[] =
14 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
15 /* No encapsulation header if EtherType < 0x600 (=length) */
16
hostap_dump_rx_80211(const char * name,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats)17 void hostap_dump_rx_80211(const char *name, struct sk_buff *skb,
18 struct hostap_80211_rx_status *rx_stats)
19 {
20 struct ieee80211_hdr_4addr *hdr;
21 u16 fc;
22
23 hdr = (struct ieee80211_hdr_4addr *) skb->data;
24
25 printk(KERN_DEBUG "%s: RX signal=%d noise=%d rate=%d len=%d "
26 "jiffies=%ld\n",
27 name, rx_stats->signal, rx_stats->noise, rx_stats->rate,
28 skb->len, jiffies);
29
30 if (skb->len < 2)
31 return;
32
33 fc = le16_to_cpu(hdr->frame_ctl);
34 printk(KERN_DEBUG " FC=0x%04x (type=%d:%d)%s%s",
35 fc, WLAN_FC_GET_TYPE(fc) >> 2, WLAN_FC_GET_STYPE(fc) >> 4,
36 fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
37 fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
38
39 if (skb->len < IEEE80211_DATA_HDR3_LEN) {
40 printk("\n");
41 return;
42 }
43
44 printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
45 le16_to_cpu(hdr->seq_ctl));
46
47 printk(KERN_DEBUG " A1=%pM", hdr->addr1);
48 printk(" A2=%pM", hdr->addr2);
49 printk(" A3=%pM", hdr->addr3);
50 if (skb->len >= 30)
51 printk(" A4=%pM", hdr->addr4);
52 printk("\n");
53 }
54
55
56 /* Send RX frame to netif with 802.11 (and possible prism) header.
57 * Called from hardware or software IRQ context. */
prism2_rx_80211(struct net_device * dev,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats,int type)58 int prism2_rx_80211(struct net_device *dev, struct sk_buff *skb,
59 struct hostap_80211_rx_status *rx_stats, int type)
60 {
61 struct hostap_interface *iface;
62 local_info_t *local;
63 int hdrlen, phdrlen, head_need, tail_need;
64 u16 fc;
65 int prism_header, ret;
66 struct ieee80211_hdr_4addr *fhdr;
67
68 iface = netdev_priv(dev);
69 local = iface->local;
70
71 if (dev->type == ARPHRD_IEEE80211_PRISM) {
72 if (local->monitor_type == PRISM2_MONITOR_PRISM) {
73 prism_header = 1;
74 phdrlen = sizeof(struct linux_wlan_ng_prism_hdr);
75 } else { /* local->monitor_type == PRISM2_MONITOR_CAPHDR */
76 prism_header = 2;
77 phdrlen = sizeof(struct linux_wlan_ng_cap_hdr);
78 }
79 } else if (dev->type == ARPHRD_IEEE80211_RADIOTAP) {
80 prism_header = 3;
81 phdrlen = sizeof(struct hostap_radiotap_rx);
82 } else {
83 prism_header = 0;
84 phdrlen = 0;
85 }
86
87 fhdr = (struct ieee80211_hdr_4addr *) skb->data;
88 fc = le16_to_cpu(fhdr->frame_ctl);
89
90 if (type == PRISM2_RX_MGMT && (fc & IEEE80211_FCTL_VERS)) {
91 printk(KERN_DEBUG "%s: dropped management frame with header "
92 "version %d\n", dev->name, fc & IEEE80211_FCTL_VERS);
93 dev_kfree_skb_any(skb);
94 return 0;
95 }
96
97 hdrlen = hostap_80211_get_hdrlen(fc);
98
99 /* check if there is enough room for extra data; if not, expand skb
100 * buffer to be large enough for the changes */
101 head_need = phdrlen;
102 tail_need = 0;
103 #ifdef PRISM2_ADD_BOGUS_CRC
104 tail_need += 4;
105 #endif /* PRISM2_ADD_BOGUS_CRC */
106
107 head_need -= skb_headroom(skb);
108 tail_need -= skb_tailroom(skb);
109
110 if (head_need > 0 || tail_need > 0) {
111 if (pskb_expand_head(skb, head_need > 0 ? head_need : 0,
112 tail_need > 0 ? tail_need : 0,
113 GFP_ATOMIC)) {
114 printk(KERN_DEBUG "%s: prism2_rx_80211 failed to "
115 "reallocate skb buffer\n", dev->name);
116 dev_kfree_skb_any(skb);
117 return 0;
118 }
119 }
120
121 /* We now have an skb with enough head and tail room, so just insert
122 * the extra data */
123
124 #ifdef PRISM2_ADD_BOGUS_CRC
125 memset(skb_put(skb, 4), 0xff, 4); /* Prism2 strips CRC */
126 #endif /* PRISM2_ADD_BOGUS_CRC */
127
128 if (prism_header == 1) {
129 struct linux_wlan_ng_prism_hdr *hdr;
130 hdr = (struct linux_wlan_ng_prism_hdr *)
131 skb_push(skb, phdrlen);
132 memset(hdr, 0, phdrlen);
133 hdr->msgcode = LWNG_CAP_DID_BASE;
134 hdr->msglen = sizeof(*hdr);
135 memcpy(hdr->devname, dev->name, sizeof(hdr->devname));
136 #define LWNG_SETVAL(f,i,s,l,d) \
137 hdr->f.did = LWNG_CAP_DID_BASE | (i << 12); \
138 hdr->f.status = s; hdr->f.len = l; hdr->f.data = d
139 LWNG_SETVAL(hosttime, 1, 0, 4, jiffies);
140 LWNG_SETVAL(mactime, 2, 0, 4, rx_stats->mac_time);
141 LWNG_SETVAL(channel, 3, 1 /* no value */, 4, 0);
142 LWNG_SETVAL(rssi, 4, 1 /* no value */, 4, 0);
143 LWNG_SETVAL(sq, 5, 1 /* no value */, 4, 0);
144 LWNG_SETVAL(signal, 6, 0, 4, rx_stats->signal);
145 LWNG_SETVAL(noise, 7, 0, 4, rx_stats->noise);
146 LWNG_SETVAL(rate, 8, 0, 4, rx_stats->rate / 5);
147 LWNG_SETVAL(istx, 9, 0, 4, 0);
148 LWNG_SETVAL(frmlen, 10, 0, 4, skb->len - phdrlen);
149 #undef LWNG_SETVAL
150 } else if (prism_header == 2) {
151 struct linux_wlan_ng_cap_hdr *hdr;
152 hdr = (struct linux_wlan_ng_cap_hdr *)
153 skb_push(skb, phdrlen);
154 memset(hdr, 0, phdrlen);
155 hdr->version = htonl(LWNG_CAPHDR_VERSION);
156 hdr->length = htonl(phdrlen);
157 hdr->mactime = __cpu_to_be64(rx_stats->mac_time);
158 hdr->hosttime = __cpu_to_be64(jiffies);
159 hdr->phytype = htonl(4); /* dss_dot11_b */
160 hdr->channel = htonl(local->channel);
161 hdr->datarate = htonl(rx_stats->rate);
162 hdr->antenna = htonl(0); /* unknown */
163 hdr->priority = htonl(0); /* unknown */
164 hdr->ssi_type = htonl(3); /* raw */
165 hdr->ssi_signal = htonl(rx_stats->signal);
166 hdr->ssi_noise = htonl(rx_stats->noise);
167 hdr->preamble = htonl(0); /* unknown */
168 hdr->encoding = htonl(1); /* cck */
169 } else if (prism_header == 3) {
170 struct hostap_radiotap_rx *hdr;
171 hdr = (struct hostap_radiotap_rx *)skb_push(skb, phdrlen);
172 memset(hdr, 0, phdrlen);
173 hdr->hdr.it_len = cpu_to_le16(phdrlen);
174 hdr->hdr.it_present =
175 cpu_to_le32((1 << IEEE80211_RADIOTAP_TSFT) |
176 (1 << IEEE80211_RADIOTAP_CHANNEL) |
177 (1 << IEEE80211_RADIOTAP_RATE) |
178 (1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL) |
179 (1 << IEEE80211_RADIOTAP_DBM_ANTNOISE));
180 hdr->tsft = cpu_to_le64(rx_stats->mac_time);
181 hdr->chan_freq = cpu_to_le16(freq_list[local->channel - 1]);
182 hdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_CCK |
183 IEEE80211_CHAN_2GHZ);
184 hdr->rate = rx_stats->rate / 5;
185 hdr->dbm_antsignal = rx_stats->signal;
186 hdr->dbm_antnoise = rx_stats->noise;
187 }
188
189 ret = skb->len - phdrlen;
190 skb->dev = dev;
191 skb_reset_mac_header(skb);
192 skb_pull(skb, hdrlen);
193 if (prism_header)
194 skb_pull(skb, phdrlen);
195 skb->pkt_type = PACKET_OTHERHOST;
196 skb->protocol = __constant_htons(ETH_P_802_2);
197 memset(skb->cb, 0, sizeof(skb->cb));
198 netif_rx(skb);
199
200 return ret;
201 }
202
203
204 /* Called only as a tasklet (software IRQ) */
monitor_rx(struct net_device * dev,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats)205 static void monitor_rx(struct net_device *dev, struct sk_buff *skb,
206 struct hostap_80211_rx_status *rx_stats)
207 {
208 struct net_device_stats *stats;
209 int len;
210
211 len = prism2_rx_80211(dev, skb, rx_stats, PRISM2_RX_MONITOR);
212 stats = hostap_get_stats(dev);
213 stats->rx_packets++;
214 stats->rx_bytes += len;
215 }
216
217
218 /* Called only as a tasklet (software IRQ) */
219 static struct prism2_frag_entry *
prism2_frag_cache_find(local_info_t * local,unsigned int seq,unsigned int frag,u8 * src,u8 * dst)220 prism2_frag_cache_find(local_info_t *local, unsigned int seq,
221 unsigned int frag, u8 *src, u8 *dst)
222 {
223 struct prism2_frag_entry *entry;
224 int i;
225
226 for (i = 0; i < PRISM2_FRAG_CACHE_LEN; i++) {
227 entry = &local->frag_cache[i];
228 if (entry->skb != NULL &&
229 time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
230 printk(KERN_DEBUG "%s: expiring fragment cache entry "
231 "seq=%u last_frag=%u\n",
232 local->dev->name, entry->seq, entry->last_frag);
233 dev_kfree_skb(entry->skb);
234 entry->skb = NULL;
235 }
236
237 if (entry->skb != NULL && entry->seq == seq &&
238 (entry->last_frag + 1 == frag || frag == -1) &&
239 memcmp(entry->src_addr, src, ETH_ALEN) == 0 &&
240 memcmp(entry->dst_addr, dst, ETH_ALEN) == 0)
241 return entry;
242 }
243
244 return NULL;
245 }
246
247
248 /* Called only as a tasklet (software IRQ) */
249 static struct sk_buff *
prism2_frag_cache_get(local_info_t * local,struct ieee80211_hdr_4addr * hdr)250 prism2_frag_cache_get(local_info_t *local, struct ieee80211_hdr_4addr *hdr)
251 {
252 struct sk_buff *skb = NULL;
253 u16 sc;
254 unsigned int frag, seq;
255 struct prism2_frag_entry *entry;
256
257 sc = le16_to_cpu(hdr->seq_ctl);
258 frag = WLAN_GET_SEQ_FRAG(sc);
259 seq = WLAN_GET_SEQ_SEQ(sc) >> 4;
260
261 if (frag == 0) {
262 /* Reserve enough space to fit maximum frame length */
263 skb = dev_alloc_skb(local->dev->mtu +
264 sizeof(struct ieee80211_hdr_4addr) +
265 8 /* LLC */ +
266 2 /* alignment */ +
267 8 /* WEP */ + ETH_ALEN /* WDS */);
268 if (skb == NULL)
269 return NULL;
270
271 entry = &local->frag_cache[local->frag_next_idx];
272 local->frag_next_idx++;
273 if (local->frag_next_idx >= PRISM2_FRAG_CACHE_LEN)
274 local->frag_next_idx = 0;
275
276 if (entry->skb != NULL)
277 dev_kfree_skb(entry->skb);
278
279 entry->first_frag_time = jiffies;
280 entry->seq = seq;
281 entry->last_frag = frag;
282 entry->skb = skb;
283 memcpy(entry->src_addr, hdr->addr2, ETH_ALEN);
284 memcpy(entry->dst_addr, hdr->addr1, ETH_ALEN);
285 } else {
286 /* received a fragment of a frame for which the head fragment
287 * should have already been received */
288 entry = prism2_frag_cache_find(local, seq, frag, hdr->addr2,
289 hdr->addr1);
290 if (entry != NULL) {
291 entry->last_frag = frag;
292 skb = entry->skb;
293 }
294 }
295
296 return skb;
297 }
298
299
300 /* Called only as a tasklet (software IRQ) */
prism2_frag_cache_invalidate(local_info_t * local,struct ieee80211_hdr_4addr * hdr)301 static int prism2_frag_cache_invalidate(local_info_t *local,
302 struct ieee80211_hdr_4addr *hdr)
303 {
304 u16 sc;
305 unsigned int seq;
306 struct prism2_frag_entry *entry;
307
308 sc = le16_to_cpu(hdr->seq_ctl);
309 seq = WLAN_GET_SEQ_SEQ(sc) >> 4;
310
311 entry = prism2_frag_cache_find(local, seq, -1, hdr->addr2, hdr->addr1);
312
313 if (entry == NULL) {
314 printk(KERN_DEBUG "%s: could not invalidate fragment cache "
315 "entry (seq=%u)\n",
316 local->dev->name, seq);
317 return -1;
318 }
319
320 entry->skb = NULL;
321 return 0;
322 }
323
324
__hostap_get_bss(local_info_t * local,u8 * bssid,u8 * ssid,size_t ssid_len)325 static struct hostap_bss_info *__hostap_get_bss(local_info_t *local, u8 *bssid,
326 u8 *ssid, size_t ssid_len)
327 {
328 struct list_head *ptr;
329 struct hostap_bss_info *bss;
330
331 list_for_each(ptr, &local->bss_list) {
332 bss = list_entry(ptr, struct hostap_bss_info, list);
333 if (memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
334 (ssid == NULL ||
335 (ssid_len == bss->ssid_len &&
336 memcmp(ssid, bss->ssid, ssid_len) == 0))) {
337 list_move(&bss->list, &local->bss_list);
338 return bss;
339 }
340 }
341
342 return NULL;
343 }
344
345
__hostap_add_bss(local_info_t * local,u8 * bssid,u8 * ssid,size_t ssid_len)346 static struct hostap_bss_info *__hostap_add_bss(local_info_t *local, u8 *bssid,
347 u8 *ssid, size_t ssid_len)
348 {
349 struct hostap_bss_info *bss;
350
351 if (local->num_bss_info >= HOSTAP_MAX_BSS_COUNT) {
352 bss = list_entry(local->bss_list.prev,
353 struct hostap_bss_info, list);
354 list_del(&bss->list);
355 local->num_bss_info--;
356 } else {
357 bss = (struct hostap_bss_info *)
358 kmalloc(sizeof(*bss), GFP_ATOMIC);
359 if (bss == NULL)
360 return NULL;
361 }
362
363 memset(bss, 0, sizeof(*bss));
364 memcpy(bss->bssid, bssid, ETH_ALEN);
365 memcpy(bss->ssid, ssid, ssid_len);
366 bss->ssid_len = ssid_len;
367 local->num_bss_info++;
368 list_add(&bss->list, &local->bss_list);
369 return bss;
370 }
371
372
__hostap_expire_bss(local_info_t * local)373 static void __hostap_expire_bss(local_info_t *local)
374 {
375 struct hostap_bss_info *bss;
376
377 while (local->num_bss_info > 0) {
378 bss = list_entry(local->bss_list.prev,
379 struct hostap_bss_info, list);
380 if (!time_after(jiffies, bss->last_update + 60 * HZ))
381 break;
382
383 list_del(&bss->list);
384 local->num_bss_info--;
385 kfree(bss);
386 }
387 }
388
389
390 /* Both IEEE 802.11 Beacon and Probe Response frames have similar structure, so
391 * the same routine can be used to parse both of them. */
hostap_rx_sta_beacon(local_info_t * local,struct sk_buff * skb,int stype)392 static void hostap_rx_sta_beacon(local_info_t *local, struct sk_buff *skb,
393 int stype)
394 {
395 struct hostap_ieee80211_mgmt *mgmt;
396 int left, chan = 0;
397 u8 *pos;
398 u8 *ssid = NULL, *wpa = NULL, *rsn = NULL;
399 size_t ssid_len = 0, wpa_len = 0, rsn_len = 0;
400 struct hostap_bss_info *bss;
401
402 if (skb->len < IEEE80211_MGMT_HDR_LEN + sizeof(mgmt->u.beacon))
403 return;
404
405 mgmt = (struct hostap_ieee80211_mgmt *) skb->data;
406 pos = mgmt->u.beacon.variable;
407 left = skb->len - (pos - skb->data);
408
409 while (left >= 2) {
410 if (2 + pos[1] > left)
411 return; /* parse failed */
412 switch (*pos) {
413 case WLAN_EID_SSID:
414 ssid = pos + 2;
415 ssid_len = pos[1];
416 break;
417 case WLAN_EID_GENERIC:
418 if (pos[1] >= 4 &&
419 pos[2] == 0x00 && pos[3] == 0x50 &&
420 pos[4] == 0xf2 && pos[5] == 1) {
421 wpa = pos;
422 wpa_len = pos[1] + 2;
423 }
424 break;
425 case WLAN_EID_RSN:
426 rsn = pos;
427 rsn_len = pos[1] + 2;
428 break;
429 case WLAN_EID_DS_PARAMS:
430 if (pos[1] >= 1)
431 chan = pos[2];
432 break;
433 }
434 left -= 2 + pos[1];
435 pos += 2 + pos[1];
436 }
437
438 if (wpa_len > MAX_WPA_IE_LEN)
439 wpa_len = MAX_WPA_IE_LEN;
440 if (rsn_len > MAX_WPA_IE_LEN)
441 rsn_len = MAX_WPA_IE_LEN;
442 if (ssid_len > sizeof(bss->ssid))
443 ssid_len = sizeof(bss->ssid);
444
445 spin_lock(&local->lock);
446 bss = __hostap_get_bss(local, mgmt->bssid, ssid, ssid_len);
447 if (bss == NULL)
448 bss = __hostap_add_bss(local, mgmt->bssid, ssid, ssid_len);
449 if (bss) {
450 bss->last_update = jiffies;
451 bss->count++;
452 bss->capab_info = le16_to_cpu(mgmt->u.beacon.capab_info);
453 if (wpa) {
454 memcpy(bss->wpa_ie, wpa, wpa_len);
455 bss->wpa_ie_len = wpa_len;
456 } else
457 bss->wpa_ie_len = 0;
458 if (rsn) {
459 memcpy(bss->rsn_ie, rsn, rsn_len);
460 bss->rsn_ie_len = rsn_len;
461 } else
462 bss->rsn_ie_len = 0;
463 bss->chan = chan;
464 }
465 __hostap_expire_bss(local);
466 spin_unlock(&local->lock);
467 }
468
469
470 static int
hostap_rx_frame_mgmt(local_info_t * local,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats,u16 type,u16 stype)471 hostap_rx_frame_mgmt(local_info_t *local, struct sk_buff *skb,
472 struct hostap_80211_rx_status *rx_stats, u16 type,
473 u16 stype)
474 {
475 if (local->iw_mode == IW_MODE_MASTER) {
476 hostap_update_sta_ps(local, (struct ieee80211_hdr_4addr *)
477 skb->data);
478 }
479
480 if (local->hostapd && type == IEEE80211_FTYPE_MGMT) {
481 if (stype == IEEE80211_STYPE_BEACON &&
482 local->iw_mode == IW_MODE_MASTER) {
483 struct sk_buff *skb2;
484 /* Process beacon frames also in kernel driver to
485 * update STA(AP) table statistics */
486 skb2 = skb_clone(skb, GFP_ATOMIC);
487 if (skb2)
488 hostap_rx(skb2->dev, skb2, rx_stats);
489 }
490
491 /* send management frames to the user space daemon for
492 * processing */
493 local->apdevstats.rx_packets++;
494 local->apdevstats.rx_bytes += skb->len;
495 if (local->apdev == NULL)
496 return -1;
497 prism2_rx_80211(local->apdev, skb, rx_stats, PRISM2_RX_MGMT);
498 return 0;
499 }
500
501 if (local->iw_mode == IW_MODE_MASTER) {
502 if (type != IEEE80211_FTYPE_MGMT &&
503 type != IEEE80211_FTYPE_CTL) {
504 printk(KERN_DEBUG "%s: unknown management frame "
505 "(type=0x%02x, stype=0x%02x) dropped\n",
506 skb->dev->name, type >> 2, stype >> 4);
507 return -1;
508 }
509
510 hostap_rx(skb->dev, skb, rx_stats);
511 return 0;
512 } else if (type == IEEE80211_FTYPE_MGMT &&
513 (stype == IEEE80211_STYPE_BEACON ||
514 stype == IEEE80211_STYPE_PROBE_RESP)) {
515 hostap_rx_sta_beacon(local, skb, stype);
516 return -1;
517 } else if (type == IEEE80211_FTYPE_MGMT &&
518 (stype == IEEE80211_STYPE_ASSOC_RESP ||
519 stype == IEEE80211_STYPE_REASSOC_RESP)) {
520 /* Ignore (Re)AssocResp silently since these are not currently
521 * needed but are still received when WPA/RSN mode is enabled.
522 */
523 return -1;
524 } else {
525 printk(KERN_DEBUG "%s: hostap_rx_frame_mgmt: dropped unhandled"
526 " management frame in non-Host AP mode (type=%d:%d)\n",
527 skb->dev->name, type >> 2, stype >> 4);
528 return -1;
529 }
530 }
531
532
533 /* Called only as a tasklet (software IRQ) */
prism2_rx_get_wds(local_info_t * local,u8 * addr)534 static struct net_device *prism2_rx_get_wds(local_info_t *local,
535 u8 *addr)
536 {
537 struct hostap_interface *iface = NULL;
538 struct list_head *ptr;
539
540 read_lock_bh(&local->iface_lock);
541 list_for_each(ptr, &local->hostap_interfaces) {
542 iface = list_entry(ptr, struct hostap_interface, list);
543 if (iface->type == HOSTAP_INTERFACE_WDS &&
544 memcmp(iface->u.wds.remote_addr, addr, ETH_ALEN) == 0)
545 break;
546 iface = NULL;
547 }
548 read_unlock_bh(&local->iface_lock);
549
550 return iface ? iface->dev : NULL;
551 }
552
553
554 static int
hostap_rx_frame_wds(local_info_t * local,struct ieee80211_hdr_4addr * hdr,u16 fc,struct net_device ** wds)555 hostap_rx_frame_wds(local_info_t *local, struct ieee80211_hdr_4addr *hdr,
556 u16 fc, struct net_device **wds)
557 {
558 /* FIX: is this really supposed to accept WDS frames only in Master
559 * mode? What about Repeater or Managed with WDS frames? */
560 if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) !=
561 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS) &&
562 (local->iw_mode != IW_MODE_MASTER || !(fc & IEEE80211_FCTL_TODS)))
563 return 0; /* not a WDS frame */
564
565 /* Possible WDS frame: either IEEE 802.11 compliant (if FromDS)
566 * or own non-standard frame with 4th address after payload */
567 if (memcmp(hdr->addr1, local->dev->dev_addr, ETH_ALEN) != 0 &&
568 (hdr->addr1[0] != 0xff || hdr->addr1[1] != 0xff ||
569 hdr->addr1[2] != 0xff || hdr->addr1[3] != 0xff ||
570 hdr->addr1[4] != 0xff || hdr->addr1[5] != 0xff)) {
571 /* RA (or BSSID) is not ours - drop */
572 PDEBUG(DEBUG_EXTRA2, "%s: received WDS frame with "
573 "not own or broadcast %s=%pM\n",
574 local->dev->name,
575 fc & IEEE80211_FCTL_FROMDS ? "RA" : "BSSID",
576 hdr->addr1);
577 return -1;
578 }
579
580 /* check if the frame came from a registered WDS connection */
581 *wds = prism2_rx_get_wds(local, hdr->addr2);
582 if (*wds == NULL && fc & IEEE80211_FCTL_FROMDS &&
583 (local->iw_mode != IW_MODE_INFRA ||
584 !(local->wds_type & HOSTAP_WDS_AP_CLIENT) ||
585 memcmp(hdr->addr2, local->bssid, ETH_ALEN) != 0)) {
586 /* require that WDS link has been registered with TA or the
587 * frame is from current AP when using 'AP client mode' */
588 PDEBUG(DEBUG_EXTRA, "%s: received WDS[4 addr] frame "
589 "from unknown TA=%pM\n",
590 local->dev->name, hdr->addr2);
591 if (local->ap && local->ap->autom_ap_wds)
592 hostap_wds_link_oper(local, hdr->addr2, WDS_ADD);
593 return -1;
594 }
595
596 if (*wds && !(fc & IEEE80211_FCTL_FROMDS) && local->ap &&
597 hostap_is_sta_assoc(local->ap, hdr->addr2)) {
598 /* STA is actually associated with us even though it has a
599 * registered WDS link. Assume it is in 'AP client' mode.
600 * Since this is a 3-addr frame, assume it is not (bogus) WDS
601 * frame and process it like any normal ToDS frame from
602 * associated STA. */
603 *wds = NULL;
604 }
605
606 return 0;
607 }
608
609
hostap_is_eapol_frame(local_info_t * local,struct sk_buff * skb)610 static int hostap_is_eapol_frame(local_info_t *local, struct sk_buff *skb)
611 {
612 struct net_device *dev = local->dev;
613 u16 fc, ethertype;
614 struct ieee80211_hdr_4addr *hdr;
615 u8 *pos;
616
617 if (skb->len < 24)
618 return 0;
619
620 hdr = (struct ieee80211_hdr_4addr *) skb->data;
621 fc = le16_to_cpu(hdr->frame_ctl);
622
623 /* check that the frame is unicast frame to us */
624 if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
625 IEEE80211_FCTL_TODS &&
626 memcmp(hdr->addr1, dev->dev_addr, ETH_ALEN) == 0 &&
627 memcmp(hdr->addr3, dev->dev_addr, ETH_ALEN) == 0) {
628 /* ToDS frame with own addr BSSID and DA */
629 } else if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
630 IEEE80211_FCTL_FROMDS &&
631 memcmp(hdr->addr1, dev->dev_addr, ETH_ALEN) == 0) {
632 /* FromDS frame with own addr as DA */
633 } else
634 return 0;
635
636 if (skb->len < 24 + 8)
637 return 0;
638
639 /* check for port access entity Ethernet type */
640 pos = skb->data + 24;
641 ethertype = (pos[6] << 8) | pos[7];
642 if (ethertype == ETH_P_PAE)
643 return 1;
644
645 return 0;
646 }
647
648
649 /* Called only as a tasklet (software IRQ) */
650 static int
hostap_rx_frame_decrypt(local_info_t * local,struct sk_buff * skb,struct lib80211_crypt_data * crypt)651 hostap_rx_frame_decrypt(local_info_t *local, struct sk_buff *skb,
652 struct lib80211_crypt_data *crypt)
653 {
654 struct ieee80211_hdr_4addr *hdr;
655 int res, hdrlen;
656
657 if (crypt == NULL || crypt->ops->decrypt_mpdu == NULL)
658 return 0;
659
660 hdr = (struct ieee80211_hdr_4addr *) skb->data;
661 hdrlen = hostap_80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));
662
663 if (local->tkip_countermeasures &&
664 strcmp(crypt->ops->name, "TKIP") == 0) {
665 if (net_ratelimit()) {
666 printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
667 "received packet from %pM\n",
668 local->dev->name, hdr->addr2);
669 }
670 return -1;
671 }
672
673 atomic_inc(&crypt->refcnt);
674 res = crypt->ops->decrypt_mpdu(skb, hdrlen, crypt->priv);
675 atomic_dec(&crypt->refcnt);
676 if (res < 0) {
677 printk(KERN_DEBUG "%s: decryption failed (SA=%pM) res=%d\n",
678 local->dev->name, hdr->addr2, res);
679 local->comm_tallies.rx_discards_wep_undecryptable++;
680 return -1;
681 }
682
683 return res;
684 }
685
686
687 /* Called only as a tasklet (software IRQ) */
688 static int
hostap_rx_frame_decrypt_msdu(local_info_t * local,struct sk_buff * skb,int keyidx,struct lib80211_crypt_data * crypt)689 hostap_rx_frame_decrypt_msdu(local_info_t *local, struct sk_buff *skb,
690 int keyidx, struct lib80211_crypt_data *crypt)
691 {
692 struct ieee80211_hdr_4addr *hdr;
693 int res, hdrlen;
694
695 if (crypt == NULL || crypt->ops->decrypt_msdu == NULL)
696 return 0;
697
698 hdr = (struct ieee80211_hdr_4addr *) skb->data;
699 hdrlen = hostap_80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));
700
701 atomic_inc(&crypt->refcnt);
702 res = crypt->ops->decrypt_msdu(skb, keyidx, hdrlen, crypt->priv);
703 atomic_dec(&crypt->refcnt);
704 if (res < 0) {
705 printk(KERN_DEBUG "%s: MSDU decryption/MIC verification failed"
706 " (SA=%pM keyidx=%d)\n",
707 local->dev->name, hdr->addr2, keyidx);
708 return -1;
709 }
710
711 return 0;
712 }
713
714
715 /* All received frames are sent to this function. @skb contains the frame in
716 * IEEE 802.11 format, i.e., in the format it was sent over air.
717 * This function is called only as a tasklet (software IRQ). */
hostap_80211_rx(struct net_device * dev,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats)718 void hostap_80211_rx(struct net_device *dev, struct sk_buff *skb,
719 struct hostap_80211_rx_status *rx_stats)
720 {
721 struct hostap_interface *iface;
722 local_info_t *local;
723 struct ieee80211_hdr_4addr *hdr;
724 size_t hdrlen;
725 u16 fc, type, stype, sc;
726 struct net_device *wds = NULL;
727 struct net_device_stats *stats;
728 unsigned int frag;
729 u8 *payload;
730 struct sk_buff *skb2 = NULL;
731 u16 ethertype;
732 int frame_authorized = 0;
733 int from_assoc_ap = 0;
734 u8 dst[ETH_ALEN];
735 u8 src[ETH_ALEN];
736 struct lib80211_crypt_data *crypt = NULL;
737 void *sta = NULL;
738 int keyidx = 0;
739
740 iface = netdev_priv(dev);
741 local = iface->local;
742 iface->stats.rx_packets++;
743 iface->stats.rx_bytes += skb->len;
744
745 /* dev is the master radio device; change this to be the default
746 * virtual interface (this may be changed to WDS device below) */
747 dev = local->ddev;
748 iface = netdev_priv(dev);
749
750 hdr = (struct ieee80211_hdr_4addr *) skb->data;
751 stats = hostap_get_stats(dev);
752
753 if (skb->len < 10)
754 goto rx_dropped;
755
756 fc = le16_to_cpu(hdr->frame_ctl);
757 type = WLAN_FC_GET_TYPE(fc);
758 stype = WLAN_FC_GET_STYPE(fc);
759 sc = le16_to_cpu(hdr->seq_ctl);
760 frag = WLAN_GET_SEQ_FRAG(sc);
761 hdrlen = hostap_80211_get_hdrlen(fc);
762
763 /* Put this code here so that we avoid duplicating it in all
764 * Rx paths. - Jean II */
765 #ifdef IW_WIRELESS_SPY /* defined in iw_handler.h */
766 /* If spy monitoring on */
767 if (iface->spy_data.spy_number > 0) {
768 struct iw_quality wstats;
769 wstats.level = rx_stats->signal;
770 wstats.noise = rx_stats->noise;
771 wstats.updated = IW_QUAL_LEVEL_UPDATED | IW_QUAL_NOISE_UPDATED
772 | IW_QUAL_QUAL_INVALID | IW_QUAL_DBM;
773 /* Update spy records */
774 wireless_spy_update(dev, hdr->addr2, &wstats);
775 }
776 #endif /* IW_WIRELESS_SPY */
777 hostap_update_rx_stats(local->ap, hdr, rx_stats);
778
779 if (local->iw_mode == IW_MODE_MONITOR) {
780 monitor_rx(dev, skb, rx_stats);
781 return;
782 }
783
784 if (local->host_decrypt) {
785 int idx = 0;
786 if (skb->len >= hdrlen + 3)
787 idx = skb->data[hdrlen + 3] >> 6;
788 crypt = local->crypt_info.crypt[idx];
789 sta = NULL;
790
791 /* Use station specific key to override default keys if the
792 * receiver address is a unicast address ("individual RA"). If
793 * bcrx_sta_key parameter is set, station specific key is used
794 * even with broad/multicast targets (this is against IEEE
795 * 802.11, but makes it easier to use different keys with
796 * stations that do not support WEP key mapping). */
797
798 if (!(hdr->addr1[0] & 0x01) || local->bcrx_sta_key)
799 (void) hostap_handle_sta_crypto(local, hdr, &crypt,
800 &sta);
801
802 /* allow NULL decrypt to indicate an station specific override
803 * for default encryption */
804 if (crypt && (crypt->ops == NULL ||
805 crypt->ops->decrypt_mpdu == NULL))
806 crypt = NULL;
807
808 if (!crypt && (fc & IEEE80211_FCTL_PROTECTED)) {
809 #if 0
810 /* This seems to be triggered by some (multicast?)
811 * frames from other than current BSS, so just drop the
812 * frames silently instead of filling system log with
813 * these reports. */
814 printk(KERN_DEBUG "%s: WEP decryption failed (not set)"
815 " (SA=%pM)\n",
816 local->dev->name, hdr->addr2);
817 #endif
818 local->comm_tallies.rx_discards_wep_undecryptable++;
819 goto rx_dropped;
820 }
821 }
822
823 if (type != IEEE80211_FTYPE_DATA) {
824 if (type == IEEE80211_FTYPE_MGMT &&
825 stype == IEEE80211_STYPE_AUTH &&
826 fc & IEEE80211_FCTL_PROTECTED && local->host_decrypt &&
827 (keyidx = hostap_rx_frame_decrypt(local, skb, crypt)) < 0)
828 {
829 printk(KERN_DEBUG "%s: failed to decrypt mgmt::auth "
830 "from %pM\n", dev->name, hdr->addr2);
831 /* TODO: could inform hostapd about this so that it
832 * could send auth failure report */
833 goto rx_dropped;
834 }
835
836 if (hostap_rx_frame_mgmt(local, skb, rx_stats, type, stype))
837 goto rx_dropped;
838 else
839 goto rx_exit;
840 }
841
842 /* Data frame - extract src/dst addresses */
843 if (skb->len < IEEE80211_DATA_HDR3_LEN)
844 goto rx_dropped;
845
846 switch (fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
847 case IEEE80211_FCTL_FROMDS:
848 memcpy(dst, hdr->addr1, ETH_ALEN);
849 memcpy(src, hdr->addr3, ETH_ALEN);
850 break;
851 case IEEE80211_FCTL_TODS:
852 memcpy(dst, hdr->addr3, ETH_ALEN);
853 memcpy(src, hdr->addr2, ETH_ALEN);
854 break;
855 case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
856 if (skb->len < IEEE80211_DATA_HDR4_LEN)
857 goto rx_dropped;
858 memcpy(dst, hdr->addr3, ETH_ALEN);
859 memcpy(src, hdr->addr4, ETH_ALEN);
860 break;
861 case 0:
862 memcpy(dst, hdr->addr1, ETH_ALEN);
863 memcpy(src, hdr->addr2, ETH_ALEN);
864 break;
865 }
866
867 if (hostap_rx_frame_wds(local, hdr, fc, &wds))
868 goto rx_dropped;
869 if (wds) {
870 skb->dev = dev = wds;
871 stats = hostap_get_stats(dev);
872 }
873
874 if (local->iw_mode == IW_MODE_MASTER && !wds &&
875 (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
876 IEEE80211_FCTL_FROMDS &&
877 local->stadev &&
878 memcmp(hdr->addr2, local->assoc_ap_addr, ETH_ALEN) == 0) {
879 /* Frame from BSSID of the AP for which we are a client */
880 skb->dev = dev = local->stadev;
881 stats = hostap_get_stats(dev);
882 from_assoc_ap = 1;
883 }
884
885 if ((local->iw_mode == IW_MODE_MASTER ||
886 local->iw_mode == IW_MODE_REPEAT) &&
887 !from_assoc_ap) {
888 switch (hostap_handle_sta_rx(local, dev, skb, rx_stats,
889 wds != NULL)) {
890 case AP_RX_CONTINUE_NOT_AUTHORIZED:
891 frame_authorized = 0;
892 break;
893 case AP_RX_CONTINUE:
894 frame_authorized = 1;
895 break;
896 case AP_RX_DROP:
897 goto rx_dropped;
898 case AP_RX_EXIT:
899 goto rx_exit;
900 }
901 }
902
903 /* Nullfunc frames may have PS-bit set, so they must be passed to
904 * hostap_handle_sta_rx() before being dropped here. */
905 if (stype != IEEE80211_STYPE_DATA &&
906 stype != IEEE80211_STYPE_DATA_CFACK &&
907 stype != IEEE80211_STYPE_DATA_CFPOLL &&
908 stype != IEEE80211_STYPE_DATA_CFACKPOLL) {
909 if (stype != IEEE80211_STYPE_NULLFUNC)
910 printk(KERN_DEBUG "%s: RX: dropped data frame "
911 "with no data (type=0x%02x, subtype=0x%02x)\n",
912 dev->name, type >> 2, stype >> 4);
913 goto rx_dropped;
914 }
915
916 /* skb: hdr + (possibly fragmented, possibly encrypted) payload */
917
918 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
919 (keyidx = hostap_rx_frame_decrypt(local, skb, crypt)) < 0)
920 goto rx_dropped;
921 hdr = (struct ieee80211_hdr_4addr *) skb->data;
922
923 /* skb: hdr + (possibly fragmented) plaintext payload */
924
925 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
926 (frag != 0 || (fc & IEEE80211_FCTL_MOREFRAGS))) {
927 int flen;
928 struct sk_buff *frag_skb =
929 prism2_frag_cache_get(local, hdr);
930 if (!frag_skb) {
931 printk(KERN_DEBUG "%s: Rx cannot get skb from "
932 "fragment cache (morefrag=%d seq=%u frag=%u)\n",
933 dev->name, (fc & IEEE80211_FCTL_MOREFRAGS) != 0,
934 WLAN_GET_SEQ_SEQ(sc) >> 4, frag);
935 goto rx_dropped;
936 }
937
938 flen = skb->len;
939 if (frag != 0)
940 flen -= hdrlen;
941
942 if (frag_skb->tail + flen > frag_skb->end) {
943 printk(KERN_WARNING "%s: host decrypted and "
944 "reassembled frame did not fit skb\n",
945 dev->name);
946 prism2_frag_cache_invalidate(local, hdr);
947 goto rx_dropped;
948 }
949
950 if (frag == 0) {
951 /* copy first fragment (including full headers) into
952 * beginning of the fragment cache skb */
953 skb_copy_from_linear_data(skb, skb_put(frag_skb, flen),
954 flen);
955 } else {
956 /* append frame payload to the end of the fragment
957 * cache skb */
958 skb_copy_from_linear_data_offset(skb, hdrlen,
959 skb_put(frag_skb,
960 flen), flen);
961 }
962 dev_kfree_skb(skb);
963 skb = NULL;
964
965 if (fc & IEEE80211_FCTL_MOREFRAGS) {
966 /* more fragments expected - leave the skb in fragment
967 * cache for now; it will be delivered to upper layers
968 * after all fragments have been received */
969 goto rx_exit;
970 }
971
972 /* this was the last fragment and the frame will be
973 * delivered, so remove skb from fragment cache */
974 skb = frag_skb;
975 hdr = (struct ieee80211_hdr_4addr *) skb->data;
976 prism2_frag_cache_invalidate(local, hdr);
977 }
978
979 /* skb: hdr + (possible reassembled) full MSDU payload; possibly still
980 * encrypted/authenticated */
981
982 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
983 hostap_rx_frame_decrypt_msdu(local, skb, keyidx, crypt))
984 goto rx_dropped;
985
986 hdr = (struct ieee80211_hdr_4addr *) skb->data;
987 if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !local->open_wep) {
988 if (local->ieee_802_1x &&
989 hostap_is_eapol_frame(local, skb)) {
990 /* pass unencrypted EAPOL frames even if encryption is
991 * configured */
992 PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X - passing "
993 "unencrypted EAPOL frame\n", local->dev->name);
994 } else {
995 printk(KERN_DEBUG "%s: encryption configured, but RX "
996 "frame not encrypted (SA=%pM)\n",
997 local->dev->name, hdr->addr2);
998 goto rx_dropped;
999 }
1000 }
1001
1002 if (local->drop_unencrypted && !(fc & IEEE80211_FCTL_PROTECTED) &&
1003 !hostap_is_eapol_frame(local, skb)) {
1004 if (net_ratelimit()) {
1005 printk(KERN_DEBUG "%s: dropped unencrypted RX data "
1006 "frame from %pM (drop_unencrypted=1)\n",
1007 dev->name, hdr->addr2);
1008 }
1009 goto rx_dropped;
1010 }
1011
1012 /* skb: hdr + (possible reassembled) full plaintext payload */
1013
1014 payload = skb->data + hdrlen;
1015 ethertype = (payload[6] << 8) | payload[7];
1016
1017 /* If IEEE 802.1X is used, check whether the port is authorized to send
1018 * the received frame. */
1019 if (local->ieee_802_1x && local->iw_mode == IW_MODE_MASTER) {
1020 if (ethertype == ETH_P_PAE) {
1021 PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X frame\n",
1022 dev->name);
1023 if (local->hostapd && local->apdev) {
1024 /* Send IEEE 802.1X frames to the user
1025 * space daemon for processing */
1026 prism2_rx_80211(local->apdev, skb, rx_stats,
1027 PRISM2_RX_MGMT);
1028 local->apdevstats.rx_packets++;
1029 local->apdevstats.rx_bytes += skb->len;
1030 goto rx_exit;
1031 }
1032 } else if (!frame_authorized) {
1033 printk(KERN_DEBUG "%s: dropped frame from "
1034 "unauthorized port (IEEE 802.1X): "
1035 "ethertype=0x%04x\n",
1036 dev->name, ethertype);
1037 goto rx_dropped;
1038 }
1039 }
1040
1041 /* convert hdr + possible LLC headers into Ethernet header */
1042 if (skb->len - hdrlen >= 8 &&
1043 ((memcmp(payload, rfc1042_header, 6) == 0 &&
1044 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1045 memcmp(payload, bridge_tunnel_header, 6) == 0)) {
1046 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1047 * replace EtherType */
1048 skb_pull(skb, hdrlen + 6);
1049 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1050 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1051 } else {
1052 __be16 len;
1053 /* Leave Ethernet header part of hdr and full payload */
1054 skb_pull(skb, hdrlen);
1055 len = htons(skb->len);
1056 memcpy(skb_push(skb, 2), &len, 2);
1057 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1058 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1059 }
1060
1061 if (wds && ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
1062 IEEE80211_FCTL_TODS) &&
1063 skb->len >= ETH_HLEN + ETH_ALEN) {
1064 /* Non-standard frame: get addr4 from its bogus location after
1065 * the payload */
1066 skb_copy_from_linear_data_offset(skb, skb->len - ETH_ALEN,
1067 skb->data + ETH_ALEN,
1068 ETH_ALEN);
1069 skb_trim(skb, skb->len - ETH_ALEN);
1070 }
1071
1072 stats->rx_packets++;
1073 stats->rx_bytes += skb->len;
1074
1075 if (local->iw_mode == IW_MODE_MASTER && !wds &&
1076 local->ap->bridge_packets) {
1077 if (dst[0] & 0x01) {
1078 /* copy multicast frame both to the higher layers and
1079 * to the wireless media */
1080 local->ap->bridged_multicast++;
1081 skb2 = skb_clone(skb, GFP_ATOMIC);
1082 if (skb2 == NULL)
1083 printk(KERN_DEBUG "%s: skb_clone failed for "
1084 "multicast frame\n", dev->name);
1085 } else if (hostap_is_sta_authorized(local->ap, dst)) {
1086 /* send frame directly to the associated STA using
1087 * wireless media and not passing to higher layers */
1088 local->ap->bridged_unicast++;
1089 skb2 = skb;
1090 skb = NULL;
1091 }
1092 }
1093
1094 if (skb2 != NULL) {
1095 /* send to wireless media */
1096 skb2->dev = dev;
1097 skb2->protocol = __constant_htons(ETH_P_802_3);
1098 skb_reset_mac_header(skb2);
1099 skb_reset_network_header(skb2);
1100 /* skb2->network_header += ETH_HLEN; */
1101 dev_queue_xmit(skb2);
1102 }
1103
1104 if (skb) {
1105 skb->protocol = eth_type_trans(skb, dev);
1106 memset(skb->cb, 0, sizeof(skb->cb));
1107 netif_rx(skb);
1108 }
1109
1110 rx_exit:
1111 if (sta)
1112 hostap_handle_sta_release(sta);
1113 return;
1114
1115 rx_dropped:
1116 dev_kfree_skb(skb);
1117
1118 stats->rx_dropped++;
1119 goto rx_exit;
1120 }
1121
1122
1123 EXPORT_SYMBOL(hostap_80211_rx);
1124