tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include "hostap_80211.h"
2#include "hostap_common.h"
3#include "hostap_wlan.h"
4#include "hostap.h"
5#include "hostap_ap.h"
6
7/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
8/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
9static unsigned char rfc1042_header[] =
10{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
11/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
12static unsigned char bridge_tunnel_header[] =
13{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
14/* No encapsulation header if EtherType < 0x600 (=length) */
15
16void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
17{
18 struct ieee80211_hdr_4addr *hdr;
19 u16 fc;
20 DECLARE_MAC_BUF(mac);
21
22 hdr = (struct ieee80211_hdr_4addr *) skb->data;
23
24 printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
25 name, skb->len, jiffies);
26
27 if (skb->len < 2)
28 return;
29
30 fc = le16_to_cpu(hdr->frame_ctl);
31 printk(KERN_DEBUG " FC=0x%04x (type=%d:%d)%s%s",
32 fc, WLAN_FC_GET_TYPE(fc) >> 2, WLAN_FC_GET_STYPE(fc) >> 4,
33 fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
34 fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
35
36 if (skb->len < IEEE80211_DATA_HDR3_LEN) {
37 printk("\n");
38 return;
39 }
40
41 printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
42 le16_to_cpu(hdr->seq_ctl));
43
44 printk(KERN_DEBUG " A1=%s", print_mac(mac, hdr->addr1));
45 printk(" A2=%s", print_mac(mac, hdr->addr2));
46 printk(" A3=%s", print_mac(mac, hdr->addr3));
47 if (skb->len >= 30)
48 printk(" A4=%s", print_mac(mac, hdr->addr4));
49 printk("\n");
50}
51
52
53/* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
54 * Convert Ethernet header into a suitable IEEE 802.11 header depending on
55 * device configuration. */
56int hostap_data_start_xmit(struct sk_buff *skb, struct net_device *dev)
57{
58 struct hostap_interface *iface;
59 local_info_t *local;
60 int need_headroom, need_tailroom = 0;
61 struct ieee80211_hdr_4addr hdr;
62 u16 fc, ethertype = 0;
63 enum {
64 WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
65 } use_wds = WDS_NO;
66 u8 *encaps_data;
67 int hdr_len, encaps_len, skip_header_bytes;
68 int to_assoc_ap = 0;
69 struct hostap_skb_tx_data *meta;
70
71 iface = netdev_priv(dev);
72 local = iface->local;
73
74 if (skb->len < ETH_HLEN) {
75 printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
76 "(len=%d)\n", dev->name, skb->len);
77 kfree_skb(skb);
78 return 0;
79 }
80
81 if (local->ddev != dev) {
82 use_wds = (local->iw_mode == IW_MODE_MASTER &&
83 !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
84 WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
85 if (dev == local->stadev) {
86 to_assoc_ap = 1;
87 use_wds = WDS_NO;
88 } else if (dev == local->apdev) {
89 printk(KERN_DEBUG "%s: prism2_tx: trying to use "
90 "AP device with Ethernet net dev\n", dev->name);
91 kfree_skb(skb);
92 return 0;
93 }
94 } else {
95 if (local->iw_mode == IW_MODE_REPEAT) {
96 printk(KERN_DEBUG "%s: prism2_tx: trying to use "
97 "non-WDS link in Repeater mode\n", dev->name);
98 kfree_skb(skb);
99 return 0;
100 } else if (local->iw_mode == IW_MODE_INFRA &&
101 (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
102 memcmp(skb->data + ETH_ALEN, dev->dev_addr,
103 ETH_ALEN) != 0) {
104 /* AP client mode: send frames with foreign src addr
105 * using 4-addr WDS frames */
106 use_wds = WDS_COMPLIANT_FRAME;
107 }
108 }
109
110 /* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
111 * ==>
112 * Prism2 TX frame with 802.11 header:
113 * txdesc (address order depending on used mode; includes dst_addr and
114 * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
115 * proto[2], payload {, possible addr4[6]} */
116
117 ethertype = (skb->data[12] << 8) | skb->data[13];
118
119 memset(&hdr, 0, sizeof(hdr));
120
121 /* Length of data after IEEE 802.11 header */
122 encaps_data = NULL;
123 encaps_len = 0;
124 skip_header_bytes = ETH_HLEN;
125 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
126 encaps_data = bridge_tunnel_header;
127 encaps_len = sizeof(bridge_tunnel_header);
128 skip_header_bytes -= 2;
129 } else if (ethertype >= 0x600) {
130 encaps_data = rfc1042_header;
131 encaps_len = sizeof(rfc1042_header);
132 skip_header_bytes -= 2;
133 }
134
135 fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
136 hdr_len = IEEE80211_DATA_HDR3_LEN;
137
138 if (use_wds != WDS_NO) {
139 /* Note! Prism2 station firmware has problems with sending real
140 * 802.11 frames with four addresses; until these problems can
141 * be fixed or worked around, 4-addr frames needed for WDS are
142 * using incompatible format: FromDS flag is not set and the
143 * fourth address is added after the frame payload; it is
144 * assumed, that the receiving station knows how to handle this
145 * frame format */
146
147 if (use_wds == WDS_COMPLIANT_FRAME) {
148 fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
149 /* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
150 * Addr4 = SA */
151 skb_copy_from_linear_data_offset(skb, ETH_ALEN,
152 &hdr.addr4, ETH_ALEN);
153 hdr_len += ETH_ALEN;
154 } else {
155 /* bogus 4-addr format to workaround Prism2 station
156 * f/w bug */
157 fc |= IEEE80211_FCTL_TODS;
158 /* From DS: Addr1 = DA (used as RA),
159 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
160 */
161
162 /* SA from skb->data + ETH_ALEN will be added after
163 * frame payload; use hdr.addr4 as a temporary buffer
164 */
165 skb_copy_from_linear_data_offset(skb, ETH_ALEN,
166 &hdr.addr4, ETH_ALEN);
167 need_tailroom += ETH_ALEN;
168 }
169
170 /* send broadcast and multicast frames to broadcast RA, if
171 * configured; otherwise, use unicast RA of the WDS link */
172 if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
173 skb->data[0] & 0x01)
174 memset(&hdr.addr1, 0xff, ETH_ALEN);
175 else if (iface->type == HOSTAP_INTERFACE_WDS)
176 memcpy(&hdr.addr1, iface->u.wds.remote_addr,
177 ETH_ALEN);
178 else
179 memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
180 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
181 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
182 } else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
183 fc |= IEEE80211_FCTL_FROMDS;
184 /* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
185 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
186 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
187 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3,
188 ETH_ALEN);
189 } else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
190 fc |= IEEE80211_FCTL_TODS;
191 /* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
192 memcpy(&hdr.addr1, to_assoc_ap ?
193 local->assoc_ap_addr : local->bssid, ETH_ALEN);
194 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
195 ETH_ALEN);
196 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
197 } else if (local->iw_mode == IW_MODE_ADHOC) {
198 /* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
199 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
200 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
201 ETH_ALEN);
202 memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
203 }
204
205 hdr.frame_ctl = cpu_to_le16(fc);
206
207 skb_pull(skb, skip_header_bytes);
208 need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
209 if (skb_tailroom(skb) < need_tailroom) {
210 skb = skb_unshare(skb, GFP_ATOMIC);
211 if (skb == NULL) {
212 iface->stats.tx_dropped++;
213 return 0;
214 }
215 if (pskb_expand_head(skb, need_headroom, need_tailroom,
216 GFP_ATOMIC)) {
217 kfree_skb(skb);
218 iface->stats.tx_dropped++;
219 return 0;
220 }
221 } else if (skb_headroom(skb) < need_headroom) {
222 struct sk_buff *tmp = skb;
223 skb = skb_realloc_headroom(skb, need_headroom);
224 kfree_skb(tmp);
225 if (skb == NULL) {
226 iface->stats.tx_dropped++;
227 return 0;
228 }
229 } else {
230 skb = skb_unshare(skb, GFP_ATOMIC);
231 if (skb == NULL) {
232 iface->stats.tx_dropped++;
233 return 0;
234 }
235 }
236
237 if (encaps_data)
238 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
239 memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
240 if (use_wds == WDS_OWN_FRAME) {
241 memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN);
242 }
243
244 iface->stats.tx_packets++;
245 iface->stats.tx_bytes += skb->len;
246
247 skb_reset_mac_header(skb);
248 meta = (struct hostap_skb_tx_data *) skb->cb;
249 memset(meta, 0, sizeof(*meta));
250 meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
251 if (use_wds)
252 meta->flags |= HOSTAP_TX_FLAGS_WDS;
253 meta->ethertype = ethertype;
254 meta->iface = iface;
255
256 /* Send IEEE 802.11 encapsulated frame using the master radio device */
257 skb->dev = local->dev;
258 dev_queue_xmit(skb);
259 return 0;
260}
261
262
263/* hard_start_xmit function for hostapd wlan#ap interfaces */
264int hostap_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
265{
266 struct hostap_interface *iface;
267 local_info_t *local;
268 struct hostap_skb_tx_data *meta;
269 struct ieee80211_hdr_4addr *hdr;
270 u16 fc;
271
272 iface = netdev_priv(dev);
273 local = iface->local;
274
275 if (skb->len < 10) {
276 printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
277 "(len=%d)\n", dev->name, skb->len);
278 kfree_skb(skb);
279 return 0;
280 }
281
282 iface->stats.tx_packets++;
283 iface->stats.tx_bytes += skb->len;
284
285 meta = (struct hostap_skb_tx_data *) skb->cb;
286 memset(meta, 0, sizeof(*meta));
287 meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
288 meta->iface = iface;
289
290 if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
291 hdr = (struct ieee80211_hdr_4addr *) skb->data;
292 fc = le16_to_cpu(hdr->frame_ctl);
293 if (WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA &&
294 WLAN_FC_GET_STYPE(fc) == IEEE80211_STYPE_DATA) {
295 u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
296 sizeof(rfc1042_header)];
297 meta->ethertype = (pos[0] << 8) | pos[1];
298 }
299 }
300
301 /* Send IEEE 802.11 encapsulated frame using the master radio device */
302 skb->dev = local->dev;
303 dev_queue_xmit(skb);
304 return 0;
305}
306
307
308/* Called only from software IRQ */
309static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
310 struct ieee80211_crypt_data *crypt)
311{
312 struct hostap_interface *iface;
313 local_info_t *local;
314 struct ieee80211_hdr_4addr *hdr;
315 u16 fc;
316 int prefix_len, postfix_len, hdr_len, res;
317
318 iface = netdev_priv(skb->dev);
319 local = iface->local;
320
321 if (skb->len < IEEE80211_DATA_HDR3_LEN) {
322 kfree_skb(skb);
323 return NULL;
324 }
325
326 if (local->tkip_countermeasures &&
327 strcmp(crypt->ops->name, "TKIP") == 0) {
328 hdr = (struct ieee80211_hdr_4addr *) skb->data;
329 if (net_ratelimit()) {
330 printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
331 "TX packet to " MAC_FMT "\n",
332 local->dev->name,
333 hdr->addr1[0], hdr->addr1[1], hdr->addr1[2],
334 hdr->addr1[3], hdr->addr1[4], hdr->addr1[5]);
335 }
336 kfree_skb(skb);
337 return NULL;
338 }
339
340 skb = skb_unshare(skb, GFP_ATOMIC);
341 if (skb == NULL)
342 return NULL;
343
344 prefix_len = crypt->ops->extra_mpdu_prefix_len +
345 crypt->ops->extra_msdu_prefix_len;
346 postfix_len = crypt->ops->extra_mpdu_postfix_len +
347 crypt->ops->extra_msdu_postfix_len;
348 if ((skb_headroom(skb) < prefix_len ||
349 skb_tailroom(skb) < postfix_len) &&
350 pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) {
351 kfree_skb(skb);
352 return NULL;
353 }
354
355 hdr = (struct ieee80211_hdr_4addr *) skb->data;
356 fc = le16_to_cpu(hdr->frame_ctl);
357 hdr_len = hostap_80211_get_hdrlen(fc);
358
359 /* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
360 * call both MSDU and MPDU encryption functions from here. */
361 atomic_inc(&crypt->refcnt);
362 res = 0;
363 if (crypt->ops->encrypt_msdu)
364 res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv);
365 if (res == 0 && crypt->ops->encrypt_mpdu)
366 res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv);
367 atomic_dec(&crypt->refcnt);
368 if (res < 0) {
369 kfree_skb(skb);
370 return NULL;
371 }
372
373 return skb;
374}
375
376
377/* hard_start_xmit function for master radio interface wifi#.
378 * AP processing (TX rate control, power save buffering, etc.).
379 * Use hardware TX function to send the frame. */
380int hostap_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
381{
382 struct hostap_interface *iface;
383 local_info_t *local;
384 int ret = 1;
385 u16 fc;
386 struct hostap_tx_data tx;
387 ap_tx_ret tx_ret;
388 struct hostap_skb_tx_data *meta;
389 int no_encrypt = 0;
390 struct ieee80211_hdr_4addr *hdr;
391
392 iface = netdev_priv(dev);
393 local = iface->local;
394
395 tx.skb = skb;
396 tx.sta_ptr = NULL;
397
398 meta = (struct hostap_skb_tx_data *) skb->cb;
399 if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
400 printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
401 "expected 0x%08x)\n",
402 dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
403 ret = 0;
404 iface->stats.tx_dropped++;
405 goto fail;
406 }
407
408 if (local->host_encrypt) {
409 /* Set crypt to default algorithm and key; will be replaced in
410 * AP code if STA has own alg/key */
411 tx.crypt = local->crypt[local->tx_keyidx];
412 tx.host_encrypt = 1;
413 } else {
414 tx.crypt = NULL;
415 tx.host_encrypt = 0;
416 }
417
418 if (skb->len < 24) {
419 printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
420 "(len=%d)\n", dev->name, skb->len);
421 ret = 0;
422 iface->stats.tx_dropped++;
423 goto fail;
424 }
425
426 /* FIX (?):
427 * Wi-Fi 802.11b test plan suggests that AP should ignore power save
428 * bit in authentication and (re)association frames and assume tha
429 * STA remains awake for the response. */
430 tx_ret = hostap_handle_sta_tx(local, &tx);
431 skb = tx.skb;
432 meta = (struct hostap_skb_tx_data *) skb->cb;
433 hdr = (struct ieee80211_hdr_4addr *) skb->data;
434 fc = le16_to_cpu(hdr->frame_ctl);
435 switch (tx_ret) {
436 case AP_TX_CONTINUE:
437 break;
438 case AP_TX_CONTINUE_NOT_AUTHORIZED:
439 if (local->ieee_802_1x &&
440 WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA &&
441 meta->ethertype != ETH_P_PAE &&
442 !(meta->flags & HOSTAP_TX_FLAGS_WDS)) {
443 printk(KERN_DEBUG "%s: dropped frame to unauthorized "
444 "port (IEEE 802.1X): ethertype=0x%04x\n",
445 dev->name, meta->ethertype);
446 hostap_dump_tx_80211(dev->name, skb);
447
448 ret = 0; /* drop packet */
449 iface->stats.tx_dropped++;
450 goto fail;
451 }
452 break;
453 case AP_TX_DROP:
454 ret = 0; /* drop packet */
455 iface->stats.tx_dropped++;
456 goto fail;
457 case AP_TX_RETRY:
458 goto fail;
459 case AP_TX_BUFFERED:
460 /* do not free skb here, it will be freed when the
461 * buffered frame is sent/timed out */
462 ret = 0;
463 goto tx_exit;
464 }
465
466 /* Request TX callback if protocol version is 2 in 802.11 header;
467 * this version 2 is a special case used between hostapd and kernel
468 * driver */
469 if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) &&
470 local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
471 meta->tx_cb_idx = local->ap->tx_callback_idx;
472
473 /* remove special version from the frame header */
474 fc &= ~IEEE80211_FCTL_VERS;
475 hdr->frame_ctl = cpu_to_le16(fc);
476 }
477
478 if (WLAN_FC_GET_TYPE(fc) != IEEE80211_FTYPE_DATA) {
479 no_encrypt = 1;
480 tx.crypt = NULL;
481 }
482
483 if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
484 !(fc & IEEE80211_FCTL_PROTECTED)) {
485 no_encrypt = 1;
486 PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
487 "unencrypted EAPOL frame\n", dev->name);
488 tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
489 }
490
491 if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
492 tx.crypt = NULL;
493 else if ((tx.crypt || local->crypt[local->tx_keyidx]) && !no_encrypt) {
494 /* Add ISWEP flag both for firmware and host based encryption
495 */
496 fc |= IEEE80211_FCTL_PROTECTED;
497 hdr->frame_ctl = cpu_to_le16(fc);
498 } else if (local->drop_unencrypted &&
499 WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA &&
500 meta->ethertype != ETH_P_PAE) {
501 if (net_ratelimit()) {
502 printk(KERN_DEBUG "%s: dropped unencrypted TX data "
503 "frame (drop_unencrypted=1)\n", dev->name);
504 }
505 iface->stats.tx_dropped++;
506 ret = 0;
507 goto fail;
508 }
509
510 if (tx.crypt) {
511 skb = hostap_tx_encrypt(skb, tx.crypt);
512 if (skb == NULL) {
513 printk(KERN_DEBUG "%s: TX - encryption failed\n",
514 dev->name);
515 ret = 0;
516 goto fail;
517 }
518 meta = (struct hostap_skb_tx_data *) skb->cb;
519 if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
520 printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
521 "expected 0x%08x) after hostap_tx_encrypt\n",
522 dev->name, meta->magic,
523 HOSTAP_SKB_TX_DATA_MAGIC);
524 ret = 0;
525 iface->stats.tx_dropped++;
526 goto fail;
527 }
528 }
529
530 if (local->func->tx == NULL || local->func->tx(skb, dev)) {
531 ret = 0;
532 iface->stats.tx_dropped++;
533 } else {
534 ret = 0;
535 iface->stats.tx_packets++;
536 iface->stats.tx_bytes += skb->len;
537 }
538
539 fail:
540 if (!ret && skb)
541 dev_kfree_skb(skb);
542 tx_exit:
543 if (tx.sta_ptr)
544 hostap_handle_sta_release(tx.sta_ptr);
545 return ret;
546}
547
548
549EXPORT_SYMBOL(hostap_master_start_xmit);