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v3.1
  1#include <linux/slab.h>
 
  2
  3#include "hostap_80211.h"
  4#include "hostap_common.h"
  5#include "hostap_wlan.h"
  6#include "hostap.h"
  7#include "hostap_ap.h"
  8
  9/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 10/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 11static unsigned char rfc1042_header[] =
 12{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 13/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
 14static unsigned char bridge_tunnel_header[] =
 15{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 16/* No encapsulation header if EtherType < 0x600 (=length) */
 17
 18void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
 19{
 20	struct ieee80211_hdr *hdr;
 21	u16 fc;
 22
 23	hdr = (struct ieee80211_hdr *) skb->data;
 24
 25	printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
 26	       name, skb->len, jiffies);
 27
 28	if (skb->len < 2)
 29		return;
 30
 31	fc = le16_to_cpu(hdr->frame_control);
 32	printk(KERN_DEBUG "   FC=0x%04x (type=%d:%d)%s%s",
 33	       fc, (fc & IEEE80211_FCTL_FTYPE) >> 2,
 34	       (fc & IEEE80211_FCTL_STYPE) >> 4,
 35	       fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
 36	       fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
 37
 38	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
 39		printk("\n");
 40		return;
 41	}
 42
 43	printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
 44	       le16_to_cpu(hdr->seq_ctrl));
 45
 46	printk(KERN_DEBUG "   A1=%pM", hdr->addr1);
 47	printk(" A2=%pM", hdr->addr2);
 48	printk(" A3=%pM", hdr->addr3);
 49	if (skb->len >= 30)
 50		printk(" A4=%pM", hdr->addr4);
 51	printk("\n");
 52}
 53
 54
 55/* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
 56 * Convert Ethernet header into a suitable IEEE 802.11 header depending on
 57 * device configuration. */
 58netdev_tx_t hostap_data_start_xmit(struct sk_buff *skb,
 59				   struct net_device *dev)
 60{
 61	struct hostap_interface *iface;
 62	local_info_t *local;
 63	int need_headroom, need_tailroom = 0;
 64	struct ieee80211_hdr hdr;
 65	u16 fc, ethertype = 0;
 66	enum {
 67		WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
 68	} use_wds = WDS_NO;
 69	u8 *encaps_data;
 70	int hdr_len, encaps_len, skip_header_bytes;
 71	int to_assoc_ap = 0;
 72	struct hostap_skb_tx_data *meta;
 73
 74	iface = netdev_priv(dev);
 75	local = iface->local;
 76
 77	if (skb->len < ETH_HLEN) {
 78		printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
 79		       "(len=%d)\n", dev->name, skb->len);
 80		kfree_skb(skb);
 81		return NETDEV_TX_OK;
 82	}
 83
 84	if (local->ddev != dev) {
 85		use_wds = (local->iw_mode == IW_MODE_MASTER &&
 86			   !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
 87			WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
 88		if (dev == local->stadev) {
 89			to_assoc_ap = 1;
 90			use_wds = WDS_NO;
 91		} else if (dev == local->apdev) {
 92			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
 93			       "AP device with Ethernet net dev\n", dev->name);
 94			kfree_skb(skb);
 95			return NETDEV_TX_OK;
 96		}
 97	} else {
 98		if (local->iw_mode == IW_MODE_REPEAT) {
 99			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
100			       "non-WDS link in Repeater mode\n", dev->name);
101			kfree_skb(skb);
102			return NETDEV_TX_OK;
103		} else if (local->iw_mode == IW_MODE_INFRA &&
104			   (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
105			   memcmp(skb->data + ETH_ALEN, dev->dev_addr,
106				  ETH_ALEN) != 0) {
107			/* AP client mode: send frames with foreign src addr
108			 * using 4-addr WDS frames */
109			use_wds = WDS_COMPLIANT_FRAME;
110		}
111	}
112
113	/* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
114	 * ==>
115	 * Prism2 TX frame with 802.11 header:
116	 * txdesc (address order depending on used mode; includes dst_addr and
117	 * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
118	 * proto[2], payload {, possible addr4[6]} */
119
120	ethertype = (skb->data[12] << 8) | skb->data[13];
121
122	memset(&hdr, 0, sizeof(hdr));
123
124	/* Length of data after IEEE 802.11 header */
125	encaps_data = NULL;
126	encaps_len = 0;
127	skip_header_bytes = ETH_HLEN;
128	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
129		encaps_data = bridge_tunnel_header;
130		encaps_len = sizeof(bridge_tunnel_header);
131		skip_header_bytes -= 2;
132	} else if (ethertype >= 0x600) {
133		encaps_data = rfc1042_header;
134		encaps_len = sizeof(rfc1042_header);
135		skip_header_bytes -= 2;
136	}
137
138	fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
139	hdr_len = IEEE80211_DATA_HDR3_LEN;
140
141	if (use_wds != WDS_NO) {
142		/* Note! Prism2 station firmware has problems with sending real
143		 * 802.11 frames with four addresses; until these problems can
144		 * be fixed or worked around, 4-addr frames needed for WDS are
145		 * using incompatible format: FromDS flag is not set and the
146		 * fourth address is added after the frame payload; it is
147		 * assumed, that the receiving station knows how to handle this
148		 * frame format */
149
150		if (use_wds == WDS_COMPLIANT_FRAME) {
151			fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
152			/* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
153			 * Addr4 = SA */
154			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
155							 &hdr.addr4, ETH_ALEN);
156			hdr_len += ETH_ALEN;
157		} else {
158			/* bogus 4-addr format to workaround Prism2 station
159			 * f/w bug */
160			fc |= IEEE80211_FCTL_TODS;
161			/* From DS: Addr1 = DA (used as RA),
162			 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
163			 */
164
165			/* SA from skb->data + ETH_ALEN will be added after
166			 * frame payload; use hdr.addr4 as a temporary buffer
167			 */
168			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
169							 &hdr.addr4, ETH_ALEN);
170			need_tailroom += ETH_ALEN;
171		}
172
173		/* send broadcast and multicast frames to broadcast RA, if
174		 * configured; otherwise, use unicast RA of the WDS link */
175		if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
176		    skb->data[0] & 0x01)
177			memset(&hdr.addr1, 0xff, ETH_ALEN);
178		else if (iface->type == HOSTAP_INTERFACE_WDS)
179			memcpy(&hdr.addr1, iface->u.wds.remote_addr,
180			       ETH_ALEN);
181		else
182			memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
183		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
184		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
185	} else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
186		fc |= IEEE80211_FCTL_FROMDS;
187		/* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
188		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
189		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
190		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3,
191						 ETH_ALEN);
192	} else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
193		fc |= IEEE80211_FCTL_TODS;
194		/* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
195		memcpy(&hdr.addr1, to_assoc_ap ?
196		       local->assoc_ap_addr : local->bssid, ETH_ALEN);
197		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
198						 ETH_ALEN);
199		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
200	} else if (local->iw_mode == IW_MODE_ADHOC) {
201		/* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
202		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
203		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
204						 ETH_ALEN);
205		memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
206	}
207
208	hdr.frame_control = cpu_to_le16(fc);
209
210	skb_pull(skb, skip_header_bytes);
211	need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
212	if (skb_tailroom(skb) < need_tailroom) {
213		skb = skb_unshare(skb, GFP_ATOMIC);
214		if (skb == NULL) {
215			iface->stats.tx_dropped++;
216			return NETDEV_TX_OK;
217		}
218		if (pskb_expand_head(skb, need_headroom, need_tailroom,
219				     GFP_ATOMIC)) {
220			kfree_skb(skb);
221			iface->stats.tx_dropped++;
222			return NETDEV_TX_OK;
223		}
224	} else if (skb_headroom(skb) < need_headroom) {
225		struct sk_buff *tmp = skb;
226		skb = skb_realloc_headroom(skb, need_headroom);
227		kfree_skb(tmp);
228		if (skb == NULL) {
229			iface->stats.tx_dropped++;
230			return NETDEV_TX_OK;
231		}
232	} else {
233		skb = skb_unshare(skb, GFP_ATOMIC);
234		if (skb == NULL) {
235			iface->stats.tx_dropped++;
236			return NETDEV_TX_OK;
237		}
238	}
239
240	if (encaps_data)
241		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
242	memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
243	if (use_wds == WDS_OWN_FRAME) {
244		memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN);
245	}
246
247	iface->stats.tx_packets++;
248	iface->stats.tx_bytes += skb->len;
249
250	skb_reset_mac_header(skb);
251	meta = (struct hostap_skb_tx_data *) skb->cb;
252	memset(meta, 0, sizeof(*meta));
253	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
254	if (use_wds)
255		meta->flags |= HOSTAP_TX_FLAGS_WDS;
256	meta->ethertype = ethertype;
257	meta->iface = iface;
258
259	/* Send IEEE 802.11 encapsulated frame using the master radio device */
260	skb->dev = local->dev;
261	dev_queue_xmit(skb);
262	return NETDEV_TX_OK;
263}
264
265
266/* hard_start_xmit function for hostapd wlan#ap interfaces */
267netdev_tx_t hostap_mgmt_start_xmit(struct sk_buff *skb,
268				   struct net_device *dev)
269{
270	struct hostap_interface *iface;
271	local_info_t *local;
272	struct hostap_skb_tx_data *meta;
273	struct ieee80211_hdr *hdr;
274	u16 fc;
275
276	iface = netdev_priv(dev);
277	local = iface->local;
278
279	if (skb->len < 10) {
280		printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
281		       "(len=%d)\n", dev->name, skb->len);
282		kfree_skb(skb);
283		return NETDEV_TX_OK;
284	}
285
286	iface->stats.tx_packets++;
287	iface->stats.tx_bytes += skb->len;
288
289	meta = (struct hostap_skb_tx_data *) skb->cb;
290	memset(meta, 0, sizeof(*meta));
291	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
292	meta->iface = iface;
293
294	if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
295		hdr = (struct ieee80211_hdr *) skb->data;
296		fc = le16_to_cpu(hdr->frame_control);
297		if (ieee80211_is_data(hdr->frame_control) &&
298		    (fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_DATA) {
299			u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
300					     sizeof(rfc1042_header)];
301			meta->ethertype = (pos[0] << 8) | pos[1];
302		}
303	}
304
305	/* Send IEEE 802.11 encapsulated frame using the master radio device */
306	skb->dev = local->dev;
307	dev_queue_xmit(skb);
308	return NETDEV_TX_OK;
309}
310
311
312/* Called only from software IRQ */
313static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
314					  struct lib80211_crypt_data *crypt)
315{
316	struct hostap_interface *iface;
317	local_info_t *local;
318	struct ieee80211_hdr *hdr;
319	int prefix_len, postfix_len, hdr_len, res;
320
321	iface = netdev_priv(skb->dev);
322	local = iface->local;
323
324	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
325		kfree_skb(skb);
326		return NULL;
327	}
328
329	if (local->tkip_countermeasures &&
330	    strcmp(crypt->ops->name, "TKIP") == 0) {
331		hdr = (struct ieee80211_hdr *) skb->data;
332		if (net_ratelimit()) {
333			printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
334			       "TX packet to %pM\n",
335			       local->dev->name, hdr->addr1);
336		}
337		kfree_skb(skb);
338		return NULL;
339	}
340
341	skb = skb_unshare(skb, GFP_ATOMIC);
342	if (skb == NULL)
343		return NULL;
344
345	prefix_len = crypt->ops->extra_mpdu_prefix_len +
346		crypt->ops->extra_msdu_prefix_len;
347	postfix_len = crypt->ops->extra_mpdu_postfix_len +
348		crypt->ops->extra_msdu_postfix_len;
349	if ((skb_headroom(skb) < prefix_len ||
350	     skb_tailroom(skb) < postfix_len) &&
351	    pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) {
352		kfree_skb(skb);
353		return NULL;
354	}
355
356	hdr = (struct ieee80211_hdr *) skb->data;
357	hdr_len = hostap_80211_get_hdrlen(hdr->frame_control);
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. */
380netdev_tx_t hostap_master_start_xmit(struct sk_buff *skb,
381				     struct net_device *dev)
382{
383	struct hostap_interface *iface;
384	local_info_t *local;
385	netdev_tx_t ret = NETDEV_TX_BUSY;
386	u16 fc;
387	struct hostap_tx_data tx;
388	ap_tx_ret tx_ret;
389	struct hostap_skb_tx_data *meta;
390	int no_encrypt = 0;
391	struct ieee80211_hdr *hdr;
392
393	iface = netdev_priv(dev);
394	local = iface->local;
395
396	tx.skb = skb;
397	tx.sta_ptr = NULL;
398
399	meta = (struct hostap_skb_tx_data *) skb->cb;
400	if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
401		printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
402		       "expected 0x%08x)\n",
403		       dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
404		ret = NETDEV_TX_OK;
405		iface->stats.tx_dropped++;
406		goto fail;
407	}
408
409	if (local->host_encrypt) {
410		/* Set crypt to default algorithm and key; will be replaced in
411		 * AP code if STA has own alg/key */
412		tx.crypt = local->crypt_info.crypt[local->crypt_info.tx_keyidx];
413		tx.host_encrypt = 1;
414	} else {
415		tx.crypt = NULL;
416		tx.host_encrypt = 0;
417	}
418
419	if (skb->len < 24) {
420		printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
421		       "(len=%d)\n", dev->name, skb->len);
422		ret = NETDEV_TX_OK;
423		iface->stats.tx_dropped++;
424		goto fail;
425	}
426
427	/* FIX (?):
428	 * Wi-Fi 802.11b test plan suggests that AP should ignore power save
429	 * bit in authentication and (re)association frames and assume tha
430	 * STA remains awake for the response. */
431	tx_ret = hostap_handle_sta_tx(local, &tx);
432	skb = tx.skb;
433	meta = (struct hostap_skb_tx_data *) skb->cb;
434	hdr = (struct ieee80211_hdr *) skb->data;
435	fc = le16_to_cpu(hdr->frame_control);
436	switch (tx_ret) {
437	case AP_TX_CONTINUE:
438		break;
439	case AP_TX_CONTINUE_NOT_AUTHORIZED:
440		if (local->ieee_802_1x &&
441		    ieee80211_is_data(hdr->frame_control) &&
442		    meta->ethertype != ETH_P_PAE &&
443		    !(meta->flags & HOSTAP_TX_FLAGS_WDS)) {
444			printk(KERN_DEBUG "%s: dropped frame to unauthorized "
445			       "port (IEEE 802.1X): ethertype=0x%04x\n",
446			       dev->name, meta->ethertype);
447			hostap_dump_tx_80211(dev->name, skb);
448
449			ret = NETDEV_TX_OK; /* drop packet */
450			iface->stats.tx_dropped++;
451			goto fail;
452		}
453		break;
454	case AP_TX_DROP:
455		ret = NETDEV_TX_OK; /* drop packet */
456		iface->stats.tx_dropped++;
457		goto fail;
458	case AP_TX_RETRY:
459		goto fail;
460	case AP_TX_BUFFERED:
461		/* do not free skb here, it will be freed when the
462		 * buffered frame is sent/timed out */
463		ret = NETDEV_TX_OK;
464		goto tx_exit;
465	}
466
467	/* Request TX callback if protocol version is 2 in 802.11 header;
468	 * this version 2 is a special case used between hostapd and kernel
469	 * driver */
470	if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) &&
471	    local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
472		meta->tx_cb_idx = local->ap->tx_callback_idx;
473
474		/* remove special version from the frame header */
475		fc &= ~IEEE80211_FCTL_VERS;
476		hdr->frame_control = cpu_to_le16(fc);
477	}
478
479	if (!ieee80211_is_data(hdr->frame_control)) {
480		no_encrypt = 1;
481		tx.crypt = NULL;
482	}
483
484	if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
485	    !(fc & IEEE80211_FCTL_PROTECTED)) {
486		no_encrypt = 1;
487		PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
488		       "unencrypted EAPOL frame\n", dev->name);
489		tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
490	}
491
492	if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
493		tx.crypt = NULL;
494	else if ((tx.crypt ||
495		 local->crypt_info.crypt[local->crypt_info.tx_keyidx]) &&
496		 !no_encrypt) {
497		/* Add ISWEP flag both for firmware and host based encryption
498		 */
499		fc |= IEEE80211_FCTL_PROTECTED;
500		hdr->frame_control = cpu_to_le16(fc);
501	} else if (local->drop_unencrypted &&
502		   ieee80211_is_data(hdr->frame_control) &&
503		   meta->ethertype != ETH_P_PAE) {
504		if (net_ratelimit()) {
505			printk(KERN_DEBUG "%s: dropped unencrypted TX data "
506			       "frame (drop_unencrypted=1)\n", dev->name);
507		}
508		iface->stats.tx_dropped++;
509		ret = NETDEV_TX_OK;
510		goto fail;
511	}
512
513	if (tx.crypt) {
514		skb = hostap_tx_encrypt(skb, tx.crypt);
515		if (skb == NULL) {
516			printk(KERN_DEBUG "%s: TX - encryption failed\n",
517			       dev->name);
518			ret = NETDEV_TX_OK;
519			goto fail;
520		}
521		meta = (struct hostap_skb_tx_data *) skb->cb;
522		if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
523			printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
524			       "expected 0x%08x) after hostap_tx_encrypt\n",
525			       dev->name, meta->magic,
526			       HOSTAP_SKB_TX_DATA_MAGIC);
527			ret = NETDEV_TX_OK;
528			iface->stats.tx_dropped++;
529			goto fail;
530		}
531	}
532
533	if (local->func->tx == NULL || local->func->tx(skb, dev)) {
534		ret = NETDEV_TX_OK;
535		iface->stats.tx_dropped++;
536	} else {
537		ret = NETDEV_TX_OK;
538		iface->stats.tx_packets++;
539		iface->stats.tx_bytes += skb->len;
540	}
541
542 fail:
543	if (ret == NETDEV_TX_OK && skb)
544		dev_kfree_skb(skb);
545 tx_exit:
546	if (tx.sta_ptr)
547		hostap_handle_sta_release(tx.sta_ptr);
548	return ret;
549}
550
551
552EXPORT_SYMBOL(hostap_master_start_xmit);
v3.5.6
  1#include <linux/slab.h>
  2#include <linux/export.h>
  3
  4#include "hostap_80211.h"
  5#include "hostap_common.h"
  6#include "hostap_wlan.h"
  7#include "hostap.h"
  8#include "hostap_ap.h"
  9
 10/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 11/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 12static unsigned char rfc1042_header[] =
 13{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 14/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
 15static unsigned char bridge_tunnel_header[] =
 16{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 17/* No encapsulation header if EtherType < 0x600 (=length) */
 18
 19void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
 20{
 21	struct ieee80211_hdr *hdr;
 22	u16 fc;
 23
 24	hdr = (struct ieee80211_hdr *) skb->data;
 25
 26	printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
 27	       name, skb->len, jiffies);
 28
 29	if (skb->len < 2)
 30		return;
 31
 32	fc = le16_to_cpu(hdr->frame_control);
 33	printk(KERN_DEBUG "   FC=0x%04x (type=%d:%d)%s%s",
 34	       fc, (fc & IEEE80211_FCTL_FTYPE) >> 2,
 35	       (fc & IEEE80211_FCTL_STYPE) >> 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_ctrl));
 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/* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
 57 * Convert Ethernet header into a suitable IEEE 802.11 header depending on
 58 * device configuration. */
 59netdev_tx_t hostap_data_start_xmit(struct sk_buff *skb,
 60				   struct net_device *dev)
 61{
 62	struct hostap_interface *iface;
 63	local_info_t *local;
 64	int need_headroom, need_tailroom = 0;
 65	struct ieee80211_hdr hdr;
 66	u16 fc, ethertype = 0;
 67	enum {
 68		WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
 69	} use_wds = WDS_NO;
 70	u8 *encaps_data;
 71	int hdr_len, encaps_len, skip_header_bytes;
 72	int to_assoc_ap = 0;
 73	struct hostap_skb_tx_data *meta;
 74
 75	iface = netdev_priv(dev);
 76	local = iface->local;
 77
 78	if (skb->len < ETH_HLEN) {
 79		printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
 80		       "(len=%d)\n", dev->name, skb->len);
 81		kfree_skb(skb);
 82		return NETDEV_TX_OK;
 83	}
 84
 85	if (local->ddev != dev) {
 86		use_wds = (local->iw_mode == IW_MODE_MASTER &&
 87			   !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
 88			WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
 89		if (dev == local->stadev) {
 90			to_assoc_ap = 1;
 91			use_wds = WDS_NO;
 92		} else if (dev == local->apdev) {
 93			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
 94			       "AP device with Ethernet net dev\n", dev->name);
 95			kfree_skb(skb);
 96			return NETDEV_TX_OK;
 97		}
 98	} else {
 99		if (local->iw_mode == IW_MODE_REPEAT) {
100			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
101			       "non-WDS link in Repeater mode\n", dev->name);
102			kfree_skb(skb);
103			return NETDEV_TX_OK;
104		} else if (local->iw_mode == IW_MODE_INFRA &&
105			   (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
106			   memcmp(skb->data + ETH_ALEN, dev->dev_addr,
107				  ETH_ALEN) != 0) {
108			/* AP client mode: send frames with foreign src addr
109			 * using 4-addr WDS frames */
110			use_wds = WDS_COMPLIANT_FRAME;
111		}
112	}
113
114	/* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
115	 * ==>
116	 * Prism2 TX frame with 802.11 header:
117	 * txdesc (address order depending on used mode; includes dst_addr and
118	 * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
119	 * proto[2], payload {, possible addr4[6]} */
120
121	ethertype = (skb->data[12] << 8) | skb->data[13];
122
123	memset(&hdr, 0, sizeof(hdr));
124
125	/* Length of data after IEEE 802.11 header */
126	encaps_data = NULL;
127	encaps_len = 0;
128	skip_header_bytes = ETH_HLEN;
129	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
130		encaps_data = bridge_tunnel_header;
131		encaps_len = sizeof(bridge_tunnel_header);
132		skip_header_bytes -= 2;
133	} else if (ethertype >= 0x600) {
134		encaps_data = rfc1042_header;
135		encaps_len = sizeof(rfc1042_header);
136		skip_header_bytes -= 2;
137	}
138
139	fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
140	hdr_len = IEEE80211_DATA_HDR3_LEN;
141
142	if (use_wds != WDS_NO) {
143		/* Note! Prism2 station firmware has problems with sending real
144		 * 802.11 frames with four addresses; until these problems can
145		 * be fixed or worked around, 4-addr frames needed for WDS are
146		 * using incompatible format: FromDS flag is not set and the
147		 * fourth address is added after the frame payload; it is
148		 * assumed, that the receiving station knows how to handle this
149		 * frame format */
150
151		if (use_wds == WDS_COMPLIANT_FRAME) {
152			fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
153			/* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
154			 * Addr4 = SA */
155			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
156							 &hdr.addr4, ETH_ALEN);
157			hdr_len += ETH_ALEN;
158		} else {
159			/* bogus 4-addr format to workaround Prism2 station
160			 * f/w bug */
161			fc |= IEEE80211_FCTL_TODS;
162			/* From DS: Addr1 = DA (used as RA),
163			 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
164			 */
165
166			/* SA from skb->data + ETH_ALEN will be added after
167			 * frame payload; use hdr.addr4 as a temporary buffer
168			 */
169			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
170							 &hdr.addr4, ETH_ALEN);
171			need_tailroom += ETH_ALEN;
172		}
173
174		/* send broadcast and multicast frames to broadcast RA, if
175		 * configured; otherwise, use unicast RA of the WDS link */
176		if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
177		    skb->data[0] & 0x01)
178			memset(&hdr.addr1, 0xff, ETH_ALEN);
179		else if (iface->type == HOSTAP_INTERFACE_WDS)
180			memcpy(&hdr.addr1, iface->u.wds.remote_addr,
181			       ETH_ALEN);
182		else
183			memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
184		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
185		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
186	} else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
187		fc |= IEEE80211_FCTL_FROMDS;
188		/* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
189		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
190		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
191		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3,
192						 ETH_ALEN);
193	} else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
194		fc |= IEEE80211_FCTL_TODS;
195		/* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
196		memcpy(&hdr.addr1, to_assoc_ap ?
197		       local->assoc_ap_addr : local->bssid, ETH_ALEN);
198		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
199						 ETH_ALEN);
200		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
201	} else if (local->iw_mode == IW_MODE_ADHOC) {
202		/* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
203		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
204		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
205						 ETH_ALEN);
206		memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
207	}
208
209	hdr.frame_control = cpu_to_le16(fc);
210
211	skb_pull(skb, skip_header_bytes);
212	need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
213	if (skb_tailroom(skb) < need_tailroom) {
214		skb = skb_unshare(skb, GFP_ATOMIC);
215		if (skb == NULL) {
216			iface->stats.tx_dropped++;
217			return NETDEV_TX_OK;
218		}
219		if (pskb_expand_head(skb, need_headroom, need_tailroom,
220				     GFP_ATOMIC)) {
221			kfree_skb(skb);
222			iface->stats.tx_dropped++;
223			return NETDEV_TX_OK;
224		}
225	} else if (skb_headroom(skb) < need_headroom) {
226		struct sk_buff *tmp = skb;
227		skb = skb_realloc_headroom(skb, need_headroom);
228		kfree_skb(tmp);
229		if (skb == NULL) {
230			iface->stats.tx_dropped++;
231			return NETDEV_TX_OK;
232		}
233	} else {
234		skb = skb_unshare(skb, GFP_ATOMIC);
235		if (skb == NULL) {
236			iface->stats.tx_dropped++;
237			return NETDEV_TX_OK;
238		}
239	}
240
241	if (encaps_data)
242		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
243	memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
244	if (use_wds == WDS_OWN_FRAME) {
245		memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN);
246	}
247
248	iface->stats.tx_packets++;
249	iface->stats.tx_bytes += skb->len;
250
251	skb_reset_mac_header(skb);
252	meta = (struct hostap_skb_tx_data *) skb->cb;
253	memset(meta, 0, sizeof(*meta));
254	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
255	if (use_wds)
256		meta->flags |= HOSTAP_TX_FLAGS_WDS;
257	meta->ethertype = ethertype;
258	meta->iface = iface;
259
260	/* Send IEEE 802.11 encapsulated frame using the master radio device */
261	skb->dev = local->dev;
262	dev_queue_xmit(skb);
263	return NETDEV_TX_OK;
264}
265
266
267/* hard_start_xmit function for hostapd wlan#ap interfaces */
268netdev_tx_t hostap_mgmt_start_xmit(struct sk_buff *skb,
269				   struct net_device *dev)
270{
271	struct hostap_interface *iface;
272	local_info_t *local;
273	struct hostap_skb_tx_data *meta;
274	struct ieee80211_hdr *hdr;
275	u16 fc;
276
277	iface = netdev_priv(dev);
278	local = iface->local;
279
280	if (skb->len < 10) {
281		printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
282		       "(len=%d)\n", dev->name, skb->len);
283		kfree_skb(skb);
284		return NETDEV_TX_OK;
285	}
286
287	iface->stats.tx_packets++;
288	iface->stats.tx_bytes += skb->len;
289
290	meta = (struct hostap_skb_tx_data *) skb->cb;
291	memset(meta, 0, sizeof(*meta));
292	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
293	meta->iface = iface;
294
295	if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
296		hdr = (struct ieee80211_hdr *) skb->data;
297		fc = le16_to_cpu(hdr->frame_control);
298		if (ieee80211_is_data(hdr->frame_control) &&
299		    (fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_DATA) {
300			u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
301					     sizeof(rfc1042_header)];
302			meta->ethertype = (pos[0] << 8) | pos[1];
303		}
304	}
305
306	/* Send IEEE 802.11 encapsulated frame using the master radio device */
307	skb->dev = local->dev;
308	dev_queue_xmit(skb);
309	return NETDEV_TX_OK;
310}
311
312
313/* Called only from software IRQ */
314static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
315					  struct lib80211_crypt_data *crypt)
316{
317	struct hostap_interface *iface;
318	local_info_t *local;
319	struct ieee80211_hdr *hdr;
320	int prefix_len, postfix_len, hdr_len, res;
321
322	iface = netdev_priv(skb->dev);
323	local = iface->local;
324
325	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
326		kfree_skb(skb);
327		return NULL;
328	}
329
330	if (local->tkip_countermeasures &&
331	    strcmp(crypt->ops->name, "TKIP") == 0) {
332		hdr = (struct ieee80211_hdr *) skb->data;
333		if (net_ratelimit()) {
334			printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
335			       "TX packet to %pM\n",
336			       local->dev->name, hdr->addr1);
337		}
338		kfree_skb(skb);
339		return NULL;
340	}
341
342	skb = skb_unshare(skb, GFP_ATOMIC);
343	if (skb == NULL)
344		return NULL;
345
346	prefix_len = crypt->ops->extra_mpdu_prefix_len +
347		crypt->ops->extra_msdu_prefix_len;
348	postfix_len = crypt->ops->extra_mpdu_postfix_len +
349		crypt->ops->extra_msdu_postfix_len;
350	if ((skb_headroom(skb) < prefix_len ||
351	     skb_tailroom(skb) < postfix_len) &&
352	    pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) {
353		kfree_skb(skb);
354		return NULL;
355	}
356
357	hdr = (struct ieee80211_hdr *) skb->data;
358	hdr_len = hostap_80211_get_hdrlen(hdr->frame_control);
359
360	/* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
361	 * call both MSDU and MPDU encryption functions from here. */
362	atomic_inc(&crypt->refcnt);
363	res = 0;
364	if (crypt->ops->encrypt_msdu)
365		res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv);
366	if (res == 0 && crypt->ops->encrypt_mpdu)
367		res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv);
368	atomic_dec(&crypt->refcnt);
369	if (res < 0) {
370		kfree_skb(skb);
371		return NULL;
372	}
373
374	return skb;
375}
376
377
378/* hard_start_xmit function for master radio interface wifi#.
379 * AP processing (TX rate control, power save buffering, etc.).
380 * Use hardware TX function to send the frame. */
381netdev_tx_t hostap_master_start_xmit(struct sk_buff *skb,
382				     struct net_device *dev)
383{
384	struct hostap_interface *iface;
385	local_info_t *local;
386	netdev_tx_t ret = NETDEV_TX_BUSY;
387	u16 fc;
388	struct hostap_tx_data tx;
389	ap_tx_ret tx_ret;
390	struct hostap_skb_tx_data *meta;
391	int no_encrypt = 0;
392	struct ieee80211_hdr *hdr;
393
394	iface = netdev_priv(dev);
395	local = iface->local;
396
397	tx.skb = skb;
398	tx.sta_ptr = NULL;
399
400	meta = (struct hostap_skb_tx_data *) skb->cb;
401	if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
402		printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
403		       "expected 0x%08x)\n",
404		       dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
405		ret = NETDEV_TX_OK;
406		iface->stats.tx_dropped++;
407		goto fail;
408	}
409
410	if (local->host_encrypt) {
411		/* Set crypt to default algorithm and key; will be replaced in
412		 * AP code if STA has own alg/key */
413		tx.crypt = local->crypt_info.crypt[local->crypt_info.tx_keyidx];
414		tx.host_encrypt = 1;
415	} else {
416		tx.crypt = NULL;
417		tx.host_encrypt = 0;
418	}
419
420	if (skb->len < 24) {
421		printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
422		       "(len=%d)\n", dev->name, skb->len);
423		ret = NETDEV_TX_OK;
424		iface->stats.tx_dropped++;
425		goto fail;
426	}
427
428	/* FIX (?):
429	 * Wi-Fi 802.11b test plan suggests that AP should ignore power save
430	 * bit in authentication and (re)association frames and assume tha
431	 * STA remains awake for the response. */
432	tx_ret = hostap_handle_sta_tx(local, &tx);
433	skb = tx.skb;
434	meta = (struct hostap_skb_tx_data *) skb->cb;
435	hdr = (struct ieee80211_hdr *) skb->data;
436	fc = le16_to_cpu(hdr->frame_control);
437	switch (tx_ret) {
438	case AP_TX_CONTINUE:
439		break;
440	case AP_TX_CONTINUE_NOT_AUTHORIZED:
441		if (local->ieee_802_1x &&
442		    ieee80211_is_data(hdr->frame_control) &&
443		    meta->ethertype != ETH_P_PAE &&
444		    !(meta->flags & HOSTAP_TX_FLAGS_WDS)) {
445			printk(KERN_DEBUG "%s: dropped frame to unauthorized "
446			       "port (IEEE 802.1X): ethertype=0x%04x\n",
447			       dev->name, meta->ethertype);
448			hostap_dump_tx_80211(dev->name, skb);
449
450			ret = NETDEV_TX_OK; /* drop packet */
451			iface->stats.tx_dropped++;
452			goto fail;
453		}
454		break;
455	case AP_TX_DROP:
456		ret = NETDEV_TX_OK; /* drop packet */
457		iface->stats.tx_dropped++;
458		goto fail;
459	case AP_TX_RETRY:
460		goto fail;
461	case AP_TX_BUFFERED:
462		/* do not free skb here, it will be freed when the
463		 * buffered frame is sent/timed out */
464		ret = NETDEV_TX_OK;
465		goto tx_exit;
466	}
467
468	/* Request TX callback if protocol version is 2 in 802.11 header;
469	 * this version 2 is a special case used between hostapd and kernel
470	 * driver */
471	if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) &&
472	    local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
473		meta->tx_cb_idx = local->ap->tx_callback_idx;
474
475		/* remove special version from the frame header */
476		fc &= ~IEEE80211_FCTL_VERS;
477		hdr->frame_control = cpu_to_le16(fc);
478	}
479
480	if (!ieee80211_is_data(hdr->frame_control)) {
481		no_encrypt = 1;
482		tx.crypt = NULL;
483	}
484
485	if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
486	    !(fc & IEEE80211_FCTL_PROTECTED)) {
487		no_encrypt = 1;
488		PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
489		       "unencrypted EAPOL frame\n", dev->name);
490		tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
491	}
492
493	if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
494		tx.crypt = NULL;
495	else if ((tx.crypt ||
496		 local->crypt_info.crypt[local->crypt_info.tx_keyidx]) &&
497		 !no_encrypt) {
498		/* Add ISWEP flag both for firmware and host based encryption
499		 */
500		fc |= IEEE80211_FCTL_PROTECTED;
501		hdr->frame_control = cpu_to_le16(fc);
502	} else if (local->drop_unencrypted &&
503		   ieee80211_is_data(hdr->frame_control) &&
504		   meta->ethertype != ETH_P_PAE) {
505		if (net_ratelimit()) {
506			printk(KERN_DEBUG "%s: dropped unencrypted TX data "
507			       "frame (drop_unencrypted=1)\n", dev->name);
508		}
509		iface->stats.tx_dropped++;
510		ret = NETDEV_TX_OK;
511		goto fail;
512	}
513
514	if (tx.crypt) {
515		skb = hostap_tx_encrypt(skb, tx.crypt);
516		if (skb == NULL) {
517			printk(KERN_DEBUG "%s: TX - encryption failed\n",
518			       dev->name);
519			ret = NETDEV_TX_OK;
520			goto fail;
521		}
522		meta = (struct hostap_skb_tx_data *) skb->cb;
523		if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
524			printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
525			       "expected 0x%08x) after hostap_tx_encrypt\n",
526			       dev->name, meta->magic,
527			       HOSTAP_SKB_TX_DATA_MAGIC);
528			ret = NETDEV_TX_OK;
529			iface->stats.tx_dropped++;
530			goto fail;
531		}
532	}
533
534	if (local->func->tx == NULL || local->func->tx(skb, dev)) {
535		ret = NETDEV_TX_OK;
536		iface->stats.tx_dropped++;
537	} else {
538		ret = NETDEV_TX_OK;
539		iface->stats.tx_packets++;
540		iface->stats.tx_bytes += skb->len;
541	}
542
543 fail:
544	if (ret == NETDEV_TX_OK && skb)
545		dev_kfree_skb(skb);
546 tx_exit:
547	if (tx.sta_ptr)
548		hostap_handle_sta_release(tx.sta_ptr);
549	return ret;
550}
551
552
553EXPORT_SYMBOL(hostap_master_start_xmit);