1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/etherdevice.h>
3 #include <linux/slab.h>
4 #include <linux/export.h>
5 #include <net/lib80211.h>
6 #include <linux/if_arp.h>
7
8 #include "hostap_80211.h"
9 #include "hostap.h"
10 #include "hostap_ap.h"
11
12 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
13 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
14 static unsigned char rfc1042_header[] =
15 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
16 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
17 static unsigned char bridge_tunnel_header[] =
18 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
19 /* No encapsulation header if EtherType < 0x600 (=length) */
20
hostap_dump_rx_80211(const char * name,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats)21 void hostap_dump_rx_80211(const char *name, struct sk_buff *skb,
22 struct hostap_80211_rx_status *rx_stats)
23 {
24 struct ieee80211_hdr *hdr;
25 u16 fc;
26
27 hdr = (struct ieee80211_hdr *) skb->data;
28
29 printk(KERN_DEBUG "%s: RX signal=%d noise=%d rate=%d len=%d "
30 "jiffies=%ld\n",
31 name, rx_stats->signal, rx_stats->noise, rx_stats->rate,
32 skb->len, jiffies);
33
34 if (skb->len < 2)
35 return;
36
37 fc = le16_to_cpu(hdr->frame_control);
38 printk(KERN_DEBUG " FC=0x%04x (type=%d:%d)%s%s",
39 fc, (fc & IEEE80211_FCTL_FTYPE) >> 2,
40 (fc & IEEE80211_FCTL_STYPE) >> 4,
41 fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
42 fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
43
44 if (skb->len < IEEE80211_DATA_HDR3_LEN) {
45 printk("\n");
46 return;
47 }
48
49 printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
50 le16_to_cpu(hdr->seq_ctrl));
51
52 printk(KERN_DEBUG " A1=%pM", hdr->addr1);
53 printk(" A2=%pM", hdr->addr2);
54 printk(" A3=%pM", hdr->addr3);
55 if (skb->len >= 30)
56 printk(" A4=%pM", hdr->addr4);
57 printk("\n");
58 }
59
60
61 /* Send RX frame to netif with 802.11 (and possible prism) header.
62 * 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)63 int prism2_rx_80211(struct net_device *dev, struct sk_buff *skb,
64 struct hostap_80211_rx_status *rx_stats, int type)
65 {
66 struct hostap_interface *iface;
67 local_info_t *local;
68 int hdrlen, phdrlen, head_need, tail_need;
69 u16 fc;
70 int prism_header, ret;
71 struct ieee80211_hdr *fhdr;
72
73 iface = netdev_priv(dev);
74 local = iface->local;
75
76 if (dev->type == ARPHRD_IEEE80211_PRISM) {
77 if (local->monitor_type == PRISM2_MONITOR_PRISM) {
78 prism_header = 1;
79 phdrlen = sizeof(struct linux_wlan_ng_prism_hdr);
80 } else { /* local->monitor_type == PRISM2_MONITOR_CAPHDR */
81 prism_header = 2;
82 phdrlen = sizeof(struct linux_wlan_ng_cap_hdr);
83 }
84 } else if (dev->type == ARPHRD_IEEE80211_RADIOTAP) {
85 prism_header = 3;
86 phdrlen = sizeof(struct hostap_radiotap_rx);
87 } else {
88 prism_header = 0;
89 phdrlen = 0;
90 }
91
92 fhdr = (struct ieee80211_hdr *) skb->data;
93 fc = le16_to_cpu(fhdr->frame_control);
94
95 if (type == PRISM2_RX_MGMT && (fc & IEEE80211_FCTL_VERS)) {
96 printk(KERN_DEBUG "%s: dropped management frame with header "
97 "version %d\n", dev->name, fc & IEEE80211_FCTL_VERS);
98 dev_kfree_skb_any(skb);
99 return 0;
100 }
101
102 hdrlen = hostap_80211_get_hdrlen(fhdr->frame_control);
103
104 /* check if there is enough room for extra data; if not, expand skb
105 * buffer to be large enough for the changes */
106 head_need = phdrlen;
107 tail_need = 0;
108 #ifdef PRISM2_ADD_BOGUS_CRC
109 tail_need += 4;
110 #endif /* PRISM2_ADD_BOGUS_CRC */
111
112 head_need -= skb_headroom(skb);
113 tail_need -= skb_tailroom(skb);
114
115 if (head_need > 0 || tail_need > 0) {
116 if (pskb_expand_head(skb, head_need > 0 ? head_need : 0,
117 tail_need > 0 ? tail_need : 0,
118 GFP_ATOMIC)) {
119 printk(KERN_DEBUG "%s: prism2_rx_80211 failed to "
120 "reallocate skb buffer\n", dev->name);
121 dev_kfree_skb_any(skb);
122 return 0;
123 }
124 }
125
126 /* We now have an skb with enough head and tail room, so just insert
127 * the extra data */
128
129 #ifdef PRISM2_ADD_BOGUS_CRC
130 memset(skb_put(skb, 4), 0xff, 4); /* Prism2 strips CRC */
131 #endif /* PRISM2_ADD_BOGUS_CRC */
132
133 if (prism_header == 1) {
134 struct linux_wlan_ng_prism_hdr *hdr;
135 hdr = skb_push(skb, phdrlen);
136 memset(hdr, 0, phdrlen);
137 hdr->msgcode = LWNG_CAP_DID_BASE;
138 hdr->msglen = sizeof(*hdr);
139 memcpy(hdr->devname, dev->name, sizeof(hdr->devname));
140 #define LWNG_SETVAL(f,i,s,l,d) \
141 hdr->f.did = LWNG_CAP_DID_BASE | (i << 12); \
142 hdr->f.status = s; hdr->f.len = l; hdr->f.data = d
143 LWNG_SETVAL(hosttime, 1, 0, 4, jiffies);
144 LWNG_SETVAL(mactime, 2, 0, 4, rx_stats->mac_time);
145 LWNG_SETVAL(channel, 3, 1 /* no value */, 4, 0);
146 LWNG_SETVAL(rssi, 4, 1 /* no value */, 4, 0);
147 LWNG_SETVAL(sq, 5, 1 /* no value */, 4, 0);
148 LWNG_SETVAL(signal, 6, 0, 4, rx_stats->signal);
149 LWNG_SETVAL(noise, 7, 0, 4, rx_stats->noise);
150 LWNG_SETVAL(rate, 8, 0, 4, rx_stats->rate / 5);
151 LWNG_SETVAL(istx, 9, 0, 4, 0);
152 LWNG_SETVAL(frmlen, 10, 0, 4, skb->len - phdrlen);
153 #undef LWNG_SETVAL
154 } else if (prism_header == 2) {
155 struct linux_wlan_ng_cap_hdr *hdr;
156 hdr = skb_push(skb, phdrlen);
157 memset(hdr, 0, phdrlen);
158 hdr->version = htonl(LWNG_CAPHDR_VERSION);
159 hdr->length = htonl(phdrlen);
160 hdr->mactime = __cpu_to_be64(rx_stats->mac_time);
161 hdr->hosttime = __cpu_to_be64(jiffies);
162 hdr->phytype = htonl(4); /* dss_dot11_b */
163 hdr->channel = htonl(local->channel);
164 hdr->datarate = htonl(rx_stats->rate);
165 hdr->antenna = htonl(0); /* unknown */
166 hdr->priority = htonl(0); /* unknown */
167 hdr->ssi_type = htonl(3); /* raw */
168 hdr->ssi_signal = htonl(rx_stats->signal);
169 hdr->ssi_noise = htonl(rx_stats->noise);
170 hdr->preamble = htonl(0); /* unknown */
171 hdr->encoding = htonl(1); /* cck */
172 } else if (prism_header == 3) {
173 struct hostap_radiotap_rx *hdr;
174 hdr = skb_push(skb, phdrlen);
175 memset(hdr, 0, phdrlen);
176 hdr->hdr.it_len = cpu_to_le16(phdrlen);
177 hdr->hdr.it_present =
178 cpu_to_le32((1 << IEEE80211_RADIOTAP_TSFT) |
179 (1 << IEEE80211_RADIOTAP_CHANNEL) |
180 (1 << IEEE80211_RADIOTAP_RATE) |
181 (1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL) |
182 (1 << IEEE80211_RADIOTAP_DBM_ANTNOISE));
183 hdr->tsft = cpu_to_le64(rx_stats->mac_time);
184 hdr->chan_freq = cpu_to_le16(freq_list[local->channel - 1]);
185 hdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_CCK |
186 IEEE80211_CHAN_2GHZ);
187 hdr->rate = rx_stats->rate / 5;
188 hdr->dbm_antsignal = rx_stats->signal;
189 hdr->dbm_antnoise = rx_stats->noise;
190 }
191
192 ret = skb->len - phdrlen;
193 skb->dev = dev;
194 skb_reset_mac_header(skb);
195 skb_pull(skb, hdrlen);
196 if (prism_header)
197 skb_pull(skb, phdrlen);
198 skb->pkt_type = PACKET_OTHERHOST;
199 skb->protocol = cpu_to_be16(ETH_P_802_2);
200 memset(skb->cb, 0, sizeof(skb->cb));
201 netif_rx(skb);
202
203 return ret;
204 }
205
206
207 /* Called only as a tasklet (software IRQ) */
monitor_rx(struct net_device * dev,struct sk_buff * skb,struct hostap_80211_rx_status * rx_stats)208 static void monitor_rx(struct net_device *dev, struct sk_buff *skb,
209 struct hostap_80211_rx_status *rx_stats)
210 {
211 int len;
212
213 len = prism2_rx_80211(dev, skb, rx_stats, PRISM2_RX_MONITOR);
214 dev->stats.rx_packets++;
215 dev->stats.rx_bytes += len;
216 }
217
218
219 /* Called only as a tasklet (software IRQ) */
220 static struct prism2_frag_entry *
prism2_frag_cache_find(local_info_t * local,unsigned int seq,unsigned int frag,u8 * src,u8 * dst)221 prism2_frag_cache_find(local_info_t *local, unsigned int seq,
222 unsigned int frag, u8 *src, u8 *dst)
223 {
224 struct prism2_frag_entry *entry;
225 int i;
226
227 for (i = 0; i < PRISM2_FRAG_CACHE_LEN; i++) {
228 entry = &local->frag_cache[i];
229 if (entry->skb != NULL &&
230 time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
231 printk(KERN_DEBUG "%s: expiring fragment cache entry "
232 "seq=%u last_frag=%u\n",
233 local->dev->name, entry->seq, entry->last_frag);
234 dev_kfree_skb(entry->skb);
235 entry->skb = NULL;
236 }
237
238 if (entry->skb != NULL && entry->seq == seq &&
239 (entry->last_frag + 1 == frag || frag == -1) &&
240 memcmp(entry->src_addr, src, ETH_ALEN) == 0 &&
241 memcmp(entry->dst_addr, dst, ETH_ALEN) == 0)
242 return entry;
243 }
244
245 return NULL;
246 }
247
248
249 /* Called only as a tasklet (software IRQ) */
250 static struct sk_buff *
prism2_frag_cache_get(local_info_t * local,struct ieee80211_hdr * hdr)251 prism2_frag_cache_get(local_info_t *local, struct ieee80211_hdr *hdr)
252 {
253 struct sk_buff *skb = NULL;
254 u16 sc;
255 unsigned int frag, seq;
256 struct prism2_frag_entry *entry;
257
258 sc = le16_to_cpu(hdr->seq_ctrl);
259 frag = sc & IEEE80211_SCTL_FRAG;
260 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
261
262 if (frag == 0) {
263 /* Reserve enough space to fit maximum frame length */
264 skb = dev_alloc_skb(local->dev->mtu +
265 sizeof(struct ieee80211_hdr) +
266 8 /* LLC */ +
267 2 /* alignment */ +
268 8 /* WEP */ + ETH_ALEN /* WDS */);
269 if (skb == NULL)
270 return NULL;
271
272 entry = &local->frag_cache[local->frag_next_idx];
273 local->frag_next_idx++;
274 if (local->frag_next_idx >= PRISM2_FRAG_CACHE_LEN)
275 local->frag_next_idx = 0;
276
277 if (entry->skb != NULL)
278 dev_kfree_skb(entry->skb);
279
280 entry->first_frag_time = jiffies;
281 entry->seq = seq;
282 entry->last_frag = frag;
283 entry->skb = skb;
284 memcpy(entry->src_addr, hdr->addr2, ETH_ALEN);
285 memcpy(entry->dst_addr, hdr->addr1, ETH_ALEN);
286 } else {
287 /* received a fragment of a frame for which the head fragment
288 * should have already been received */
289 entry = prism2_frag_cache_find(local, seq, frag, hdr->addr2,
290 hdr->addr1);
291 if (entry != NULL) {
292 entry->last_frag = frag;
293 skb = entry->skb;
294 }
295 }
296
297 return skb;
298 }
299
300
301 /* Called only as a tasklet (software IRQ) */
prism2_frag_cache_invalidate(local_info_t * local,struct ieee80211_hdr * hdr)302 static int prism2_frag_cache_invalidate(local_info_t *local,
303 struct ieee80211_hdr *hdr)
304 {
305 u16 sc;
306 unsigned int seq;
307 struct prism2_frag_entry *entry;
308
309 sc = le16_to_cpu(hdr->seq_ctrl);
310 seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
311
312 entry = prism2_frag_cache_find(local, seq, -1, hdr->addr2, hdr->addr1);
313
314 if (entry == NULL) {
315 printk(KERN_DEBUG "%s: could not invalidate fragment cache "
316 "entry (seq=%u)\n",
317 local->dev->name, seq);
318 return -1;
319 }
320
321 entry->skb = NULL;
322 return 0;
323 }
324
325
__hostap_get_bss(local_info_t * local,u8 * bssid,u8 * ssid,size_t ssid_len)326 static struct hostap_bss_info *__hostap_get_bss(local_info_t *local, u8 *bssid,
327 u8 *ssid, size_t ssid_len)
328 {
329 struct list_head *ptr;
330 struct hostap_bss_info *bss;
331
332 list_for_each(ptr, &local->bss_list) {
333 bss = list_entry(ptr, struct hostap_bss_info, list);
334 if (memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
335 (ssid == NULL ||
336 (ssid_len == bss->ssid_len &&
337 memcmp(ssid, bss->ssid, ssid_len) == 0))) {
338 list_move(&bss->list, &local->bss_list);
339 return bss;
340 }
341 }
342
343 return NULL;
344 }
345
346
__hostap_add_bss(local_info_t * local,u8 * bssid,u8 * ssid,size_t ssid_len)347 static struct hostap_bss_info *__hostap_add_bss(local_info_t *local, u8 *bssid,
348 u8 *ssid, size_t ssid_len)
349 {
350 struct hostap_bss_info *bss;
351
352 if (local->num_bss_info >= HOSTAP_MAX_BSS_COUNT) {
353 bss = list_entry(local->bss_list.prev,
354 struct hostap_bss_info, list);
355 list_del(&bss->list);
356 local->num_bss_info--;
357 } else {
358 bss = 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_VENDOR_SPECIFIC:
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 *) skb->data);
477
478 if (local->hostapd && type == IEEE80211_FTYPE_MGMT) {
479 if (stype == IEEE80211_STYPE_BEACON &&
480 local->iw_mode == IW_MODE_MASTER) {
481 struct sk_buff *skb2;
482 /* Process beacon frames also in kernel driver to
483 * update STA(AP) table statistics */
484 skb2 = skb_clone(skb, GFP_ATOMIC);
485 if (skb2)
486 hostap_rx(skb2->dev, skb2, rx_stats);
487 }
488
489 /* send management frames to the user space daemon for
490 * processing */
491 local->apdevstats.rx_packets++;
492 local->apdevstats.rx_bytes += skb->len;
493 if (local->apdev == NULL)
494 return -1;
495 prism2_rx_80211(local->apdev, skb, rx_stats, PRISM2_RX_MGMT);
496 return 0;
497 }
498
499 if (local->iw_mode == IW_MODE_MASTER) {
500 if (type != IEEE80211_FTYPE_MGMT &&
501 type != IEEE80211_FTYPE_CTL) {
502 printk(KERN_DEBUG "%s: unknown management frame "
503 "(type=0x%02x, stype=0x%02x) dropped\n",
504 skb->dev->name, type >> 2, stype >> 4);
505 return -1;
506 }
507
508 hostap_rx(skb->dev, skb, rx_stats);
509 return 0;
510 } else if (type == IEEE80211_FTYPE_MGMT &&
511 (stype == IEEE80211_STYPE_BEACON ||
512 stype == IEEE80211_STYPE_PROBE_RESP)) {
513 hostap_rx_sta_beacon(local, skb, stype);
514 return -1;
515 } else if (type == IEEE80211_FTYPE_MGMT &&
516 (stype == IEEE80211_STYPE_ASSOC_RESP ||
517 stype == IEEE80211_STYPE_REASSOC_RESP)) {
518 /* Ignore (Re)AssocResp silently since these are not currently
519 * needed but are still received when WPA/RSN mode is enabled.
520 */
521 return -1;
522 } else {
523 printk(KERN_DEBUG "%s: hostap_rx_frame_mgmt: dropped unhandled"
524 " management frame in non-Host AP mode (type=%d:%d)\n",
525 skb->dev->name, type >> 2, stype >> 4);
526 return -1;
527 }
528 }
529
530
531 /* Called only as a tasklet (software IRQ) */
prism2_rx_get_wds(local_info_t * local,u8 * addr)532 static struct net_device *prism2_rx_get_wds(local_info_t *local,
533 u8 *addr)
534 {
535 struct hostap_interface *iface = NULL;
536 struct list_head *ptr;
537
538 read_lock_bh(&local->iface_lock);
539 list_for_each(ptr, &local->hostap_interfaces) {
540 iface = list_entry(ptr, struct hostap_interface, list);
541 if (iface->type == HOSTAP_INTERFACE_WDS &&
542 memcmp(iface->u.wds.remote_addr, addr, ETH_ALEN) == 0)
543 break;
544 iface = NULL;
545 }
546 read_unlock_bh(&local->iface_lock);
547
548 return iface ? iface->dev : NULL;
549 }
550
551
552 static int
hostap_rx_frame_wds(local_info_t * local,struct ieee80211_hdr * hdr,u16 fc,struct net_device ** wds)553 hostap_rx_frame_wds(local_info_t *local, struct ieee80211_hdr *hdr, u16 fc,
554 struct net_device **wds)
555 {
556 /* FIX: is this really supposed to accept WDS frames only in Master
557 * mode? What about Repeater or Managed with WDS frames? */
558 if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) !=
559 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS) &&
560 (local->iw_mode != IW_MODE_MASTER || !(fc & IEEE80211_FCTL_TODS)))
561 return 0; /* not a WDS frame */
562
563 /* Possible WDS frame: either IEEE 802.11 compliant (if FromDS)
564 * or own non-standard frame with 4th address after payload */
565 if (!ether_addr_equal(hdr->addr1, local->dev->dev_addr) &&
566 (hdr->addr1[0] != 0xff || hdr->addr1[1] != 0xff ||
567 hdr->addr1[2] != 0xff || hdr->addr1[3] != 0xff ||
568 hdr->addr1[4] != 0xff || hdr->addr1[5] != 0xff)) {
569 /* RA (or BSSID) is not ours - drop */
570 PDEBUG(DEBUG_EXTRA2, "%s: received WDS frame with "
571 "not own or broadcast %s=%pM\n",
572 local->dev->name,
573 fc & IEEE80211_FCTL_FROMDS ? "RA" : "BSSID",
574 hdr->addr1);
575 return -1;
576 }
577
578 /* check if the frame came from a registered WDS connection */
579 *wds = prism2_rx_get_wds(local, hdr->addr2);
580 if (*wds == NULL && fc & IEEE80211_FCTL_FROMDS &&
581 (local->iw_mode != IW_MODE_INFRA ||
582 !(local->wds_type & HOSTAP_WDS_AP_CLIENT) ||
583 memcmp(hdr->addr2, local->bssid, ETH_ALEN) != 0)) {
584 /* require that WDS link has been registered with TA or the
585 * frame is from current AP when using 'AP client mode' */
586 PDEBUG(DEBUG_EXTRA, "%s: received WDS[4 addr] frame "
587 "from unknown TA=%pM\n",
588 local->dev->name, hdr->addr2);
589 if (local->ap && local->ap->autom_ap_wds)
590 hostap_wds_link_oper(local, hdr->addr2, WDS_ADD);
591 return -1;
592 }
593
594 if (*wds && !(fc & IEEE80211_FCTL_FROMDS) && local->ap &&
595 hostap_is_sta_assoc(local->ap, hdr->addr2)) {
596 /* STA is actually associated with us even though it has a
597 * registered WDS link. Assume it is in 'AP client' mode.
598 * Since this is a 3-addr frame, assume it is not (bogus) WDS
599 * frame and process it like any normal ToDS frame from
600 * associated STA. */
601 *wds = NULL;
602 }
603
604 return 0;
605 }
606
607
hostap_is_eapol_frame(local_info_t * local,struct sk_buff * skb)608 static int hostap_is_eapol_frame(local_info_t *local, struct sk_buff *skb)
609 {
610 struct net_device *dev = local->dev;
611 u16 fc, ethertype;
612 struct ieee80211_hdr *hdr;
613 u8 *pos;
614
615 if (skb->len < 24)
616 return 0;
617
618 hdr = (struct ieee80211_hdr *) skb->data;
619 fc = le16_to_cpu(hdr->frame_control);
620
621 /* check that the frame is unicast frame to us */
622 if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
623 IEEE80211_FCTL_TODS &&
624 ether_addr_equal(hdr->addr1, dev->dev_addr) &&
625 ether_addr_equal(hdr->addr3, dev->dev_addr)) {
626 /* ToDS frame with own addr BSSID and DA */
627 } else if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
628 IEEE80211_FCTL_FROMDS &&
629 ether_addr_equal(hdr->addr1, dev->dev_addr)) {
630 /* FromDS frame with own addr as DA */
631 } else
632 return 0;
633
634 if (skb->len < 24 + 8)
635 return 0;
636
637 /* check for port access entity Ethernet type */
638 pos = skb->data + 24;
639 ethertype = (pos[6] << 8) | pos[7];
640 if (ethertype == ETH_P_PAE)
641 return 1;
642
643 return 0;
644 }
645
646
647 /* Called only as a tasklet (software IRQ) */
648 static int
hostap_rx_frame_decrypt(local_info_t * local,struct sk_buff * skb,struct lib80211_crypt_data * crypt)649 hostap_rx_frame_decrypt(local_info_t *local, struct sk_buff *skb,
650 struct lib80211_crypt_data *crypt)
651 {
652 struct ieee80211_hdr *hdr;
653 int res, hdrlen;
654
655 if (crypt == NULL || crypt->ops->decrypt_mpdu == NULL)
656 return 0;
657
658 hdr = (struct ieee80211_hdr *) skb->data;
659 hdrlen = hostap_80211_get_hdrlen(hdr->frame_control);
660
661 if (local->tkip_countermeasures &&
662 strcmp(crypt->ops->name, "TKIP") == 0) {
663 if (net_ratelimit()) {
664 printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
665 "received packet from %pM\n",
666 local->dev->name, hdr->addr2);
667 }
668 return -1;
669 }
670
671 atomic_inc(&crypt->refcnt);
672 res = crypt->ops->decrypt_mpdu(skb, hdrlen, crypt->priv);
673 atomic_dec(&crypt->refcnt);
674 if (res < 0) {
675 printk(KERN_DEBUG "%s: decryption failed (SA=%pM) res=%d\n",
676 local->dev->name, hdr->addr2, res);
677 local->comm_tallies.rx_discards_wep_undecryptable++;
678 return -1;
679 }
680
681 return res;
682 }
683
684
685 /* Called only as a tasklet (software IRQ) */
686 static int
hostap_rx_frame_decrypt_msdu(local_info_t * local,struct sk_buff * skb,int keyidx,struct lib80211_crypt_data * crypt)687 hostap_rx_frame_decrypt_msdu(local_info_t *local, struct sk_buff *skb,
688 int keyidx, struct lib80211_crypt_data *crypt)
689 {
690 struct ieee80211_hdr *hdr;
691 int res, hdrlen;
692
693 if (crypt == NULL || crypt->ops->decrypt_msdu == NULL)
694 return 0;
695
696 hdr = (struct ieee80211_hdr *) skb->data;
697 hdrlen = hostap_80211_get_hdrlen(hdr->frame_control);
698
699 atomic_inc(&crypt->refcnt);
700 res = crypt->ops->decrypt_msdu(skb, keyidx, hdrlen, crypt->priv);
701 atomic_dec(&crypt->refcnt);
702 if (res < 0) {
703 printk(KERN_DEBUG "%s: MSDU decryption/MIC verification failed"
704 " (SA=%pM keyidx=%d)\n",
705 local->dev->name, hdr->addr2, keyidx);
706 return -1;
707 }
708
709 return 0;
710 }
711
712
713 /* All received frames are sent to this function. @skb contains the frame in
714 * IEEE 802.11 format, i.e., in the format it was sent over air.
715 * 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)716 void hostap_80211_rx(struct net_device *dev, struct sk_buff *skb,
717 struct hostap_80211_rx_status *rx_stats)
718 {
719 struct hostap_interface *iface;
720 local_info_t *local;
721 struct ieee80211_hdr *hdr;
722 size_t hdrlen;
723 u16 fc, type, stype, sc;
724 struct net_device *wds = NULL;
725 unsigned int frag;
726 u8 *payload;
727 struct sk_buff *skb2 = NULL;
728 u16 ethertype;
729 int frame_authorized = 0;
730 int from_assoc_ap = 0;
731 u8 dst[ETH_ALEN];
732 u8 src[ETH_ALEN];
733 struct lib80211_crypt_data *crypt = NULL;
734 void *sta = NULL;
735 int keyidx = 0;
736
737 iface = netdev_priv(dev);
738 local = iface->local;
739 iface->stats.rx_packets++;
740 iface->stats.rx_bytes += skb->len;
741
742 /* dev is the master radio device; change this to be the default
743 * virtual interface (this may be changed to WDS device below) */
744 dev = local->ddev;
745 iface = netdev_priv(dev);
746
747 hdr = (struct ieee80211_hdr *) skb->data;
748
749 if (skb->len < 10)
750 goto rx_dropped;
751
752 fc = le16_to_cpu(hdr->frame_control);
753 type = fc & IEEE80211_FCTL_FTYPE;
754 stype = fc & IEEE80211_FCTL_STYPE;
755 sc = le16_to_cpu(hdr->seq_ctrl);
756 frag = sc & IEEE80211_SCTL_FRAG;
757 hdrlen = hostap_80211_get_hdrlen(hdr->frame_control);
758
759 /* Put this code here so that we avoid duplicating it in all
760 * Rx paths. - Jean II */
761 #ifdef IW_WIRELESS_SPY /* defined in iw_handler.h */
762 /* If spy monitoring on */
763 if (iface->spy_data.spy_number > 0) {
764 struct iw_quality wstats;
765 wstats.level = rx_stats->signal;
766 wstats.noise = rx_stats->noise;
767 wstats.updated = IW_QUAL_LEVEL_UPDATED | IW_QUAL_NOISE_UPDATED
768 | IW_QUAL_QUAL_INVALID | IW_QUAL_DBM;
769 /* Update spy records */
770 wireless_spy_update(dev, hdr->addr2, &wstats);
771 }
772 #endif /* IW_WIRELESS_SPY */
773 hostap_update_rx_stats(local->ap, hdr, rx_stats);
774
775 if (local->iw_mode == IW_MODE_MONITOR) {
776 monitor_rx(dev, skb, rx_stats);
777 return;
778 }
779
780 if (local->host_decrypt) {
781 int idx = 0;
782 if (skb->len >= hdrlen + 3)
783 idx = skb->data[hdrlen + 3] >> 6;
784 crypt = local->crypt_info.crypt[idx];
785 sta = NULL;
786
787 /* Use station specific key to override default keys if the
788 * receiver address is a unicast address ("individual RA"). If
789 * bcrx_sta_key parameter is set, station specific key is used
790 * even with broad/multicast targets (this is against IEEE
791 * 802.11, but makes it easier to use different keys with
792 * stations that do not support WEP key mapping). */
793
794 if (!(hdr->addr1[0] & 0x01) || local->bcrx_sta_key)
795 (void) hostap_handle_sta_crypto(local, hdr, &crypt,
796 &sta);
797
798 /* allow NULL decrypt to indicate an station specific override
799 * for default encryption */
800 if (crypt && (crypt->ops == NULL ||
801 crypt->ops->decrypt_mpdu == NULL))
802 crypt = NULL;
803
804 if (!crypt && (fc & IEEE80211_FCTL_PROTECTED)) {
805 #if 0
806 /* This seems to be triggered by some (multicast?)
807 * frames from other than current BSS, so just drop the
808 * frames silently instead of filling system log with
809 * these reports. */
810 printk(KERN_DEBUG "%s: WEP decryption failed (not set)"
811 " (SA=%pM)\n",
812 local->dev->name, hdr->addr2);
813 #endif
814 local->comm_tallies.rx_discards_wep_undecryptable++;
815 goto rx_dropped;
816 }
817 }
818
819 if (type != IEEE80211_FTYPE_DATA) {
820 if (type == IEEE80211_FTYPE_MGMT &&
821 stype == IEEE80211_STYPE_AUTH &&
822 fc & IEEE80211_FCTL_PROTECTED && local->host_decrypt &&
823 (keyidx = hostap_rx_frame_decrypt(local, skb, crypt)) < 0)
824 {
825 printk(KERN_DEBUG "%s: failed to decrypt mgmt::auth "
826 "from %pM\n", dev->name, hdr->addr2);
827 /* TODO: could inform hostapd about this so that it
828 * could send auth failure report */
829 goto rx_dropped;
830 }
831
832 if (hostap_rx_frame_mgmt(local, skb, rx_stats, type, stype))
833 goto rx_dropped;
834 else
835 goto rx_exit;
836 }
837
838 /* Data frame - extract src/dst addresses */
839 if (skb->len < IEEE80211_DATA_HDR3_LEN)
840 goto rx_dropped;
841
842 switch (fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
843 case IEEE80211_FCTL_FROMDS:
844 memcpy(dst, hdr->addr1, ETH_ALEN);
845 memcpy(src, hdr->addr3, ETH_ALEN);
846 break;
847 case IEEE80211_FCTL_TODS:
848 memcpy(dst, hdr->addr3, ETH_ALEN);
849 memcpy(src, hdr->addr2, ETH_ALEN);
850 break;
851 case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
852 if (skb->len < IEEE80211_DATA_HDR4_LEN)
853 goto rx_dropped;
854 memcpy(dst, hdr->addr3, ETH_ALEN);
855 memcpy(src, hdr->addr4, ETH_ALEN);
856 break;
857 default:
858 memcpy(dst, hdr->addr1, ETH_ALEN);
859 memcpy(src, hdr->addr2, ETH_ALEN);
860 break;
861 }
862
863 if (hostap_rx_frame_wds(local, hdr, fc, &wds))
864 goto rx_dropped;
865 if (wds)
866 skb->dev = dev = wds;
867
868 if (local->iw_mode == IW_MODE_MASTER && !wds &&
869 (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
870 IEEE80211_FCTL_FROMDS &&
871 local->stadev &&
872 memcmp(hdr->addr2, local->assoc_ap_addr, ETH_ALEN) == 0) {
873 /* Frame from BSSID of the AP for which we are a client */
874 skb->dev = dev = local->stadev;
875 from_assoc_ap = 1;
876 }
877
878 if ((local->iw_mode == IW_MODE_MASTER ||
879 local->iw_mode == IW_MODE_REPEAT) &&
880 !from_assoc_ap) {
881 switch (hostap_handle_sta_rx(local, dev, skb, rx_stats,
882 wds != NULL)) {
883 case AP_RX_CONTINUE_NOT_AUTHORIZED:
884 frame_authorized = 0;
885 break;
886 case AP_RX_CONTINUE:
887 frame_authorized = 1;
888 break;
889 case AP_RX_DROP:
890 goto rx_dropped;
891 case AP_RX_EXIT:
892 goto rx_exit;
893 }
894 }
895
896 /* Nullfunc frames may have PS-bit set, so they must be passed to
897 * hostap_handle_sta_rx() before being dropped here. */
898 if (stype != IEEE80211_STYPE_DATA &&
899 stype != IEEE80211_STYPE_DATA_CFACK &&
900 stype != IEEE80211_STYPE_DATA_CFPOLL &&
901 stype != IEEE80211_STYPE_DATA_CFACKPOLL) {
902 if (stype != IEEE80211_STYPE_NULLFUNC)
903 printk(KERN_DEBUG "%s: RX: dropped data frame "
904 "with no data (type=0x%02x, subtype=0x%02x)\n",
905 dev->name, type >> 2, stype >> 4);
906 goto rx_dropped;
907 }
908
909 /* skb: hdr + (possibly fragmented, possibly encrypted) payload */
910
911 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
912 (keyidx = hostap_rx_frame_decrypt(local, skb, crypt)) < 0)
913 goto rx_dropped;
914 hdr = (struct ieee80211_hdr *) skb->data;
915
916 /* skb: hdr + (possibly fragmented) plaintext payload */
917
918 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
919 (frag != 0 || (fc & IEEE80211_FCTL_MOREFRAGS))) {
920 int flen;
921 struct sk_buff *frag_skb =
922 prism2_frag_cache_get(local, hdr);
923 if (!frag_skb) {
924 printk(KERN_DEBUG "%s: Rx cannot get skb from "
925 "fragment cache (morefrag=%d seq=%u frag=%u)\n",
926 dev->name, (fc & IEEE80211_FCTL_MOREFRAGS) != 0,
927 (sc & IEEE80211_SCTL_SEQ) >> 4, frag);
928 goto rx_dropped;
929 }
930
931 flen = skb->len;
932 if (frag != 0)
933 flen -= hdrlen;
934
935 if (frag_skb->tail + flen > frag_skb->end) {
936 printk(KERN_WARNING "%s: host decrypted and "
937 "reassembled frame did not fit skb\n",
938 dev->name);
939 prism2_frag_cache_invalidate(local, hdr);
940 goto rx_dropped;
941 }
942
943 if (frag == 0) {
944 /* copy first fragment (including full headers) into
945 * beginning of the fragment cache skb */
946 skb_copy_from_linear_data(skb, skb_put(frag_skb, flen),
947 flen);
948 } else {
949 /* append frame payload to the end of the fragment
950 * cache skb */
951 skb_copy_from_linear_data_offset(skb, hdrlen,
952 skb_put(frag_skb,
953 flen), flen);
954 }
955 dev_kfree_skb(skb);
956 skb = NULL;
957
958 if (fc & IEEE80211_FCTL_MOREFRAGS) {
959 /* more fragments expected - leave the skb in fragment
960 * cache for now; it will be delivered to upper layers
961 * after all fragments have been received */
962 goto rx_exit;
963 }
964
965 /* this was the last fragment and the frame will be
966 * delivered, so remove skb from fragment cache */
967 skb = frag_skb;
968 hdr = (struct ieee80211_hdr *) skb->data;
969 prism2_frag_cache_invalidate(local, hdr);
970 }
971
972 /* skb: hdr + (possible reassembled) full MSDU payload; possibly still
973 * encrypted/authenticated */
974
975 if (local->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
976 hostap_rx_frame_decrypt_msdu(local, skb, keyidx, crypt))
977 goto rx_dropped;
978
979 hdr = (struct ieee80211_hdr *) skb->data;
980 if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !local->open_wep) {
981 if (local->ieee_802_1x &&
982 hostap_is_eapol_frame(local, skb)) {
983 /* pass unencrypted EAPOL frames even if encryption is
984 * configured */
985 PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X - passing "
986 "unencrypted EAPOL frame\n", local->dev->name);
987 } else {
988 printk(KERN_DEBUG "%s: encryption configured, but RX "
989 "frame not encrypted (SA=%pM)\n",
990 local->dev->name, hdr->addr2);
991 goto rx_dropped;
992 }
993 }
994
995 if (local->drop_unencrypted && !(fc & IEEE80211_FCTL_PROTECTED) &&
996 !hostap_is_eapol_frame(local, skb)) {
997 if (net_ratelimit()) {
998 printk(KERN_DEBUG "%s: dropped unencrypted RX data "
999 "frame from %pM (drop_unencrypted=1)\n",
1000 dev->name, hdr->addr2);
1001 }
1002 goto rx_dropped;
1003 }
1004
1005 /* skb: hdr + (possible reassembled) full plaintext payload */
1006
1007 payload = skb->data + hdrlen;
1008 ethertype = (payload[6] << 8) | payload[7];
1009
1010 /* If IEEE 802.1X is used, check whether the port is authorized to send
1011 * the received frame. */
1012 if (local->ieee_802_1x && local->iw_mode == IW_MODE_MASTER) {
1013 if (ethertype == ETH_P_PAE) {
1014 PDEBUG(DEBUG_EXTRA2, "%s: RX: IEEE 802.1X frame\n",
1015 dev->name);
1016 if (local->hostapd && local->apdev) {
1017 /* Send IEEE 802.1X frames to the user
1018 * space daemon for processing */
1019 prism2_rx_80211(local->apdev, skb, rx_stats,
1020 PRISM2_RX_MGMT);
1021 local->apdevstats.rx_packets++;
1022 local->apdevstats.rx_bytes += skb->len;
1023 goto rx_exit;
1024 }
1025 } else if (!frame_authorized) {
1026 printk(KERN_DEBUG "%s: dropped frame from "
1027 "unauthorized port (IEEE 802.1X): "
1028 "ethertype=0x%04x\n",
1029 dev->name, ethertype);
1030 goto rx_dropped;
1031 }
1032 }
1033
1034 /* convert hdr + possible LLC headers into Ethernet header */
1035 if (skb->len - hdrlen >= 8 &&
1036 ((memcmp(payload, rfc1042_header, 6) == 0 &&
1037 ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1038 memcmp(payload, bridge_tunnel_header, 6) == 0)) {
1039 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1040 * replace EtherType */
1041 skb_pull(skb, hdrlen + 6);
1042 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1043 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1044 } else {
1045 __be16 len;
1046 /* Leave Ethernet header part of hdr and full payload */
1047 skb_pull(skb, hdrlen);
1048 len = htons(skb->len);
1049 memcpy(skb_push(skb, 2), &len, 2);
1050 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1051 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1052 }
1053
1054 if (wds && ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
1055 IEEE80211_FCTL_TODS) &&
1056 skb->len >= ETH_HLEN + ETH_ALEN) {
1057 /* Non-standard frame: get addr4 from its bogus location after
1058 * the payload */
1059 skb_copy_from_linear_data_offset(skb, skb->len - ETH_ALEN,
1060 skb->data + ETH_ALEN,
1061 ETH_ALEN);
1062 skb_trim(skb, skb->len - ETH_ALEN);
1063 }
1064
1065 dev->stats.rx_packets++;
1066 dev->stats.rx_bytes += skb->len;
1067
1068 if (local->iw_mode == IW_MODE_MASTER && !wds &&
1069 local->ap->bridge_packets) {
1070 if (dst[0] & 0x01) {
1071 /* copy multicast frame both to the higher layers and
1072 * to the wireless media */
1073 local->ap->bridged_multicast++;
1074 skb2 = skb_clone(skb, GFP_ATOMIC);
1075 if (skb2 == NULL)
1076 printk(KERN_DEBUG "%s: skb_clone failed for "
1077 "multicast frame\n", dev->name);
1078 } else if (hostap_is_sta_authorized(local->ap, dst)) {
1079 /* send frame directly to the associated STA using
1080 * wireless media and not passing to higher layers */
1081 local->ap->bridged_unicast++;
1082 skb2 = skb;
1083 skb = NULL;
1084 }
1085 }
1086
1087 if (skb2 != NULL) {
1088 /* send to wireless media */
1089 skb2->dev = dev;
1090 skb2->protocol = cpu_to_be16(ETH_P_802_3);
1091 skb_reset_mac_header(skb2);
1092 skb_reset_network_header(skb2);
1093 /* skb2->network_header += ETH_HLEN; */
1094 dev_queue_xmit(skb2);
1095 }
1096
1097 if (skb) {
1098 skb->protocol = eth_type_trans(skb, dev);
1099 memset(skb->cb, 0, sizeof(skb->cb));
1100 netif_rx(skb);
1101 }
1102
1103 rx_exit:
1104 if (sta)
1105 hostap_handle_sta_release(sta);
1106 return;
1107
1108 rx_dropped:
1109 dev_kfree_skb(skb);
1110
1111 dev->stats.rx_dropped++;
1112 goto rx_exit;
1113 }
1114
1115
1116 EXPORT_SYMBOL(hostap_80211_rx);
1117