1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/slab.h>
3 #include <linux/export.h>
4 #include <linux/etherdevice.h>
5 
6 #include "hostap_80211.h"
7 #include "hostap_common.h"
8 #include "hostap_wlan.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 
21 void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
22 {
23 	struct ieee80211_hdr *hdr;
24 	u16 fc;
25 
26 	hdr = (struct ieee80211_hdr *) skb->data;
27 
28 	printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
29 	       name, skb->len, jiffies);
30 
31 	if (skb->len < 2)
32 		return;
33 
34 	fc = le16_to_cpu(hdr->frame_control);
35 	printk(KERN_DEBUG "   FC=0x%04x (type=%d:%d)%s%s",
36 	       fc, (fc & IEEE80211_FCTL_FTYPE) >> 2,
37 	       (fc & IEEE80211_FCTL_STYPE) >> 4,
38 	       fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
39 	       fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
40 
41 	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
42 		printk("\n");
43 		return;
44 	}
45 
46 	printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
47 	       le16_to_cpu(hdr->seq_ctrl));
48 
49 	printk(KERN_DEBUG "   A1=%pM", hdr->addr1);
50 	printk(" A2=%pM", hdr->addr2);
51 	printk(" A3=%pM", hdr->addr3);
52 	if (skb->len >= 30)
53 		printk(" A4=%pM", hdr->addr4);
54 	printk("\n");
55 }
56 
57 
58 /* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
59  * Convert Ethernet header into a suitable IEEE 802.11 header depending on
60  * device configuration. */
61 netdev_tx_t hostap_data_start_xmit(struct sk_buff *skb,
62 				   struct net_device *dev)
63 {
64 	struct hostap_interface *iface;
65 	local_info_t *local;
66 	int need_headroom, need_tailroom = 0;
67 	struct ieee80211_hdr hdr;
68 	u16 fc, ethertype = 0;
69 	enum {
70 		WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
71 	} use_wds = WDS_NO;
72 	u8 *encaps_data;
73 	int hdr_len, encaps_len, skip_header_bytes;
74 	int to_assoc_ap = 0;
75 	struct hostap_skb_tx_data *meta;
76 
77 	iface = netdev_priv(dev);
78 	local = iface->local;
79 
80 	if (skb->len < ETH_HLEN) {
81 		printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
82 		       "(len=%d)\n", dev->name, skb->len);
83 		kfree_skb(skb);
84 		return NETDEV_TX_OK;
85 	}
86 
87 	if (local->ddev != dev) {
88 		use_wds = (local->iw_mode == IW_MODE_MASTER &&
89 			   !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
90 			WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
91 		if (dev == local->stadev) {
92 			to_assoc_ap = 1;
93 			use_wds = WDS_NO;
94 		} else if (dev == local->apdev) {
95 			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
96 			       "AP device with Ethernet net dev\n", dev->name);
97 			kfree_skb(skb);
98 			return NETDEV_TX_OK;
99 		}
100 	} else {
101 		if (local->iw_mode == IW_MODE_REPEAT) {
102 			printk(KERN_DEBUG "%s: prism2_tx: trying to use "
103 			       "non-WDS link in Repeater mode\n", dev->name);
104 			kfree_skb(skb);
105 			return NETDEV_TX_OK;
106 		} else if (local->iw_mode == IW_MODE_INFRA &&
107 			   (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
108 			   !ether_addr_equal(skb->data + ETH_ALEN, dev->dev_addr)) {
109 			/* AP client mode: send frames with foreign src addr
110 			 * using 4-addr WDS frames */
111 			use_wds = WDS_COMPLIANT_FRAME;
112 		}
113 	}
114 
115 	/* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
116 	 * ==>
117 	 * Prism2 TX frame with 802.11 header:
118 	 * txdesc (address order depending on used mode; includes dst_addr and
119 	 * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
120 	 * proto[2], payload {, possible addr4[6]} */
121 
122 	ethertype = (skb->data[12] << 8) | skb->data[13];
123 
124 	memset(&hdr, 0, sizeof(hdr));
125 
126 	/* Length of data after IEEE 802.11 header */
127 	encaps_data = NULL;
128 	encaps_len = 0;
129 	skip_header_bytes = ETH_HLEN;
130 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
131 		encaps_data = bridge_tunnel_header;
132 		encaps_len = sizeof(bridge_tunnel_header);
133 		skip_header_bytes -= 2;
134 	} else if (ethertype >= 0x600) {
135 		encaps_data = rfc1042_header;
136 		encaps_len = sizeof(rfc1042_header);
137 		skip_header_bytes -= 2;
138 	}
139 
140 	fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
141 	hdr_len = IEEE80211_DATA_HDR3_LEN;
142 
143 	if (use_wds != WDS_NO) {
144 		/* Note! Prism2 station firmware has problems with sending real
145 		 * 802.11 frames with four addresses; until these problems can
146 		 * be fixed or worked around, 4-addr frames needed for WDS are
147 		 * using incompatible format: FromDS flag is not set and the
148 		 * fourth address is added after the frame payload; it is
149 		 * assumed, that the receiving station knows how to handle this
150 		 * frame format */
151 
152 		if (use_wds == WDS_COMPLIANT_FRAME) {
153 			fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
154 			/* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
155 			 * Addr4 = SA */
156 			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
157 							 &hdr.addr4, ETH_ALEN);
158 			hdr_len += ETH_ALEN;
159 		} else {
160 			/* bogus 4-addr format to workaround Prism2 station
161 			 * f/w bug */
162 			fc |= IEEE80211_FCTL_TODS;
163 			/* From DS: Addr1 = DA (used as RA),
164 			 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
165 			 */
166 
167 			/* SA from skb->data + ETH_ALEN will be added after
168 			 * frame payload; use hdr.addr4 as a temporary buffer
169 			 */
170 			skb_copy_from_linear_data_offset(skb, ETH_ALEN,
171 							 &hdr.addr4, ETH_ALEN);
172 			need_tailroom += ETH_ALEN;
173 		}
174 
175 		/* send broadcast and multicast frames to broadcast RA, if
176 		 * configured; otherwise, use unicast RA of the WDS link */
177 		if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
178 		    is_multicast_ether_addr(skb->data))
179 			eth_broadcast_addr(hdr.addr1);
180 		else if (iface->type == HOSTAP_INTERFACE_WDS)
181 			memcpy(&hdr.addr1, iface->u.wds.remote_addr,
182 			       ETH_ALEN);
183 		else
184 			memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
185 		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
186 		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
187 	} else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
188 		fc |= IEEE80211_FCTL_FROMDS;
189 		/* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
190 		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
191 		memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
192 		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3,
193 						 ETH_ALEN);
194 	} else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
195 		fc |= IEEE80211_FCTL_TODS;
196 		/* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
197 		memcpy(&hdr.addr1, to_assoc_ap ?
198 		       local->assoc_ap_addr : local->bssid, ETH_ALEN);
199 		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
200 						 ETH_ALEN);
201 		skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
202 	} else if (local->iw_mode == IW_MODE_ADHOC) {
203 		/* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
204 		skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
205 		skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
206 						 ETH_ALEN);
207 		memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
208 	}
209 
210 	hdr.frame_control = cpu_to_le16(fc);
211 
212 	skb_pull(skb, skip_header_bytes);
213 	need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
214 	if (skb_tailroom(skb) < need_tailroom) {
215 		skb = skb_unshare(skb, GFP_ATOMIC);
216 		if (skb == NULL) {
217 			iface->stats.tx_dropped++;
218 			return NETDEV_TX_OK;
219 		}
220 		if (pskb_expand_head(skb, need_headroom, need_tailroom,
221 				     GFP_ATOMIC)) {
222 			kfree_skb(skb);
223 			iface->stats.tx_dropped++;
224 			return NETDEV_TX_OK;
225 		}
226 	} else if (skb_headroom(skb) < need_headroom) {
227 		struct sk_buff *tmp = skb;
228 		skb = skb_realloc_headroom(skb, need_headroom);
229 		kfree_skb(tmp);
230 		if (skb == NULL) {
231 			iface->stats.tx_dropped++;
232 			return NETDEV_TX_OK;
233 		}
234 	} else {
235 		skb = skb_unshare(skb, GFP_ATOMIC);
236 		if (skb == NULL) {
237 			iface->stats.tx_dropped++;
238 			return NETDEV_TX_OK;
239 		}
240 	}
241 
242 	if (encaps_data)
243 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
244 	memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
245 	if (use_wds == WDS_OWN_FRAME) {
246 		skb_put_data(skb, &hdr.addr4, ETH_ALEN);
247 	}
248 
249 	iface->stats.tx_packets++;
250 	iface->stats.tx_bytes += skb->len;
251 
252 	skb_reset_mac_header(skb);
253 	meta = (struct hostap_skb_tx_data *) skb->cb;
254 	memset(meta, 0, sizeof(*meta));
255 	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
256 	if (use_wds)
257 		meta->flags |= HOSTAP_TX_FLAGS_WDS;
258 	meta->ethertype = ethertype;
259 	meta->iface = iface;
260 
261 	/* Send IEEE 802.11 encapsulated frame using the master radio device */
262 	skb->dev = local->dev;
263 	dev_queue_xmit(skb);
264 	return NETDEV_TX_OK;
265 }
266 
267 
268 /* hard_start_xmit function for hostapd wlan#ap interfaces */
269 netdev_tx_t hostap_mgmt_start_xmit(struct sk_buff *skb,
270 				   struct net_device *dev)
271 {
272 	struct hostap_interface *iface;
273 	local_info_t *local;
274 	struct hostap_skb_tx_data *meta;
275 	struct ieee80211_hdr *hdr;
276 	u16 fc;
277 
278 	iface = netdev_priv(dev);
279 	local = iface->local;
280 
281 	if (skb->len < 10) {
282 		printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
283 		       "(len=%d)\n", dev->name, skb->len);
284 		kfree_skb(skb);
285 		return NETDEV_TX_OK;
286 	}
287 
288 	iface->stats.tx_packets++;
289 	iface->stats.tx_bytes += skb->len;
290 
291 	meta = (struct hostap_skb_tx_data *) skb->cb;
292 	memset(meta, 0, sizeof(*meta));
293 	meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
294 	meta->iface = iface;
295 
296 	if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
297 		hdr = (struct ieee80211_hdr *) skb->data;
298 		fc = le16_to_cpu(hdr->frame_control);
299 		if (ieee80211_is_data(hdr->frame_control) &&
300 		    (fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_DATA) {
301 			u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
302 					     sizeof(rfc1042_header)];
303 			meta->ethertype = (pos[0] << 8) | pos[1];
304 		}
305 	}
306 
307 	/* Send IEEE 802.11 encapsulated frame using the master radio device */
308 	skb->dev = local->dev;
309 	dev_queue_xmit(skb);
310 	return NETDEV_TX_OK;
311 }
312 
313 
314 /* Called only from software IRQ */
315 static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
316 					  struct lib80211_crypt_data *crypt)
317 {
318 	struct hostap_interface *iface;
319 	local_info_t *local;
320 	struct ieee80211_hdr *hdr;
321 	int prefix_len, postfix_len, hdr_len, res;
322 
323 	iface = netdev_priv(skb->dev);
324 	local = iface->local;
325 
326 	if (skb->len < IEEE80211_DATA_HDR3_LEN) {
327 		kfree_skb(skb);
328 		return NULL;
329 	}
330 
331 	if (local->tkip_countermeasures &&
332 	    strcmp(crypt->ops->name, "TKIP") == 0) {
333 		hdr = (struct ieee80211_hdr *) skb->data;
334 		if (net_ratelimit()) {
335 			printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
336 			       "TX packet to %pM\n",
337 			       local->dev->name, hdr->addr1);
338 		}
339 		kfree_skb(skb);
340 		return NULL;
341 	}
342 
343 	skb = skb_unshare(skb, GFP_ATOMIC);
344 	if (skb == NULL)
345 		return NULL;
346 
347 	prefix_len = crypt->ops->extra_mpdu_prefix_len +
348 		crypt->ops->extra_msdu_prefix_len;
349 	postfix_len = crypt->ops->extra_mpdu_postfix_len +
350 		crypt->ops->extra_msdu_postfix_len;
351 	if ((skb_headroom(skb) < prefix_len ||
352 	     skb_tailroom(skb) < postfix_len) &&
353 	    pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) {
354 		kfree_skb(skb);
355 		return NULL;
356 	}
357 
358 	hdr = (struct ieee80211_hdr *) skb->data;
359 	hdr_len = hostap_80211_get_hdrlen(hdr->frame_control);
360 
361 	/* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
362 	 * call both MSDU and MPDU encryption functions from here. */
363 	atomic_inc(&crypt->refcnt);
364 	res = 0;
365 	if (crypt->ops->encrypt_msdu)
366 		res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv);
367 	if (res == 0 && crypt->ops->encrypt_mpdu)
368 		res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv);
369 	atomic_dec(&crypt->refcnt);
370 	if (res < 0) {
371 		kfree_skb(skb);
372 		return NULL;
373 	}
374 
375 	return skb;
376 }
377 
378 
379 /* hard_start_xmit function for master radio interface wifi#.
380  * AP processing (TX rate control, power save buffering, etc.).
381  * Use hardware TX function to send the frame. */
382 netdev_tx_t hostap_master_start_xmit(struct sk_buff *skb,
383 				     struct net_device *dev)
384 {
385 	struct hostap_interface *iface;
386 	local_info_t *local;
387 	netdev_tx_t ret = NETDEV_TX_BUSY;
388 	u16 fc;
389 	struct hostap_tx_data tx;
390 	ap_tx_ret tx_ret;
391 	struct hostap_skb_tx_data *meta;
392 	int no_encrypt = 0;
393 	struct ieee80211_hdr *hdr;
394 
395 	iface = netdev_priv(dev);
396 	local = iface->local;
397 
398 	tx.skb = skb;
399 	tx.sta_ptr = NULL;
400 
401 	meta = (struct hostap_skb_tx_data *) skb->cb;
402 	if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
403 		printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
404 		       "expected 0x%08x)\n",
405 		       dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
406 		ret = NETDEV_TX_OK;
407 		iface->stats.tx_dropped++;
408 		goto fail;
409 	}
410 
411 	if (local->host_encrypt) {
412 		/* Set crypt to default algorithm and key; will be replaced in
413 		 * AP code if STA has own alg/key */
414 		tx.crypt = local->crypt_info.crypt[local->crypt_info.tx_keyidx];
415 		tx.host_encrypt = 1;
416 	} else {
417 		tx.crypt = NULL;
418 		tx.host_encrypt = 0;
419 	}
420 
421 	if (skb->len < 24) {
422 		printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
423 		       "(len=%d)\n", dev->name, skb->len);
424 		ret = NETDEV_TX_OK;
425 		iface->stats.tx_dropped++;
426 		goto fail;
427 	}
428 
429 	/* FIX (?):
430 	 * Wi-Fi 802.11b test plan suggests that AP should ignore power save
431 	 * bit in authentication and (re)association frames and assume tha
432 	 * STA remains awake for the response. */
433 	tx_ret = hostap_handle_sta_tx(local, &tx);
434 	skb = tx.skb;
435 	meta = (struct hostap_skb_tx_data *) skb->cb;
436 	hdr = (struct ieee80211_hdr *) skb->data;
437 	fc = le16_to_cpu(hdr->frame_control);
438 	switch (tx_ret) {
439 	case AP_TX_CONTINUE:
440 		break;
441 	case AP_TX_CONTINUE_NOT_AUTHORIZED:
442 		if (local->ieee_802_1x &&
443 		    ieee80211_is_data(hdr->frame_control) &&
444 		    meta->ethertype != ETH_P_PAE &&
445 		    !(meta->flags & HOSTAP_TX_FLAGS_WDS)) {
446 			printk(KERN_DEBUG "%s: dropped frame to unauthorized "
447 			       "port (IEEE 802.1X): ethertype=0x%04x\n",
448 			       dev->name, meta->ethertype);
449 			hostap_dump_tx_80211(dev->name, skb);
450 
451 			ret = NETDEV_TX_OK; /* drop packet */
452 			iface->stats.tx_dropped++;
453 			goto fail;
454 		}
455 		break;
456 	case AP_TX_DROP:
457 		ret = NETDEV_TX_OK; /* drop packet */
458 		iface->stats.tx_dropped++;
459 		goto fail;
460 	case AP_TX_RETRY:
461 		goto fail;
462 	case AP_TX_BUFFERED:
463 		/* do not free skb here, it will be freed when the
464 		 * buffered frame is sent/timed out */
465 		ret = NETDEV_TX_OK;
466 		goto tx_exit;
467 	}
468 
469 	/* Request TX callback if protocol version is 2 in 802.11 header;
470 	 * this version 2 is a special case used between hostapd and kernel
471 	 * driver */
472 	if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) &&
473 	    local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
474 		meta->tx_cb_idx = local->ap->tx_callback_idx;
475 
476 		/* remove special version from the frame header */
477 		fc &= ~IEEE80211_FCTL_VERS;
478 		hdr->frame_control = cpu_to_le16(fc);
479 	}
480 
481 	if (!ieee80211_is_data(hdr->frame_control)) {
482 		no_encrypt = 1;
483 		tx.crypt = NULL;
484 	}
485 
486 	if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
487 	    !(fc & IEEE80211_FCTL_PROTECTED)) {
488 		no_encrypt = 1;
489 		PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
490 		       "unencrypted EAPOL frame\n", dev->name);
491 		tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
492 	}
493 
494 	if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
495 		tx.crypt = NULL;
496 	else if ((tx.crypt ||
497 		 local->crypt_info.crypt[local->crypt_info.tx_keyidx]) &&
498 		 !no_encrypt) {
499 		/* Add ISWEP flag both for firmware and host based encryption
500 		 */
501 		fc |= IEEE80211_FCTL_PROTECTED;
502 		hdr->frame_control = cpu_to_le16(fc);
503 	} else if (local->drop_unencrypted &&
504 		   ieee80211_is_data(hdr->frame_control) &&
505 		   meta->ethertype != ETH_P_PAE) {
506 		if (net_ratelimit()) {
507 			printk(KERN_DEBUG "%s: dropped unencrypted TX data "
508 			       "frame (drop_unencrypted=1)\n", dev->name);
509 		}
510 		iface->stats.tx_dropped++;
511 		ret = NETDEV_TX_OK;
512 		goto fail;
513 	}
514 
515 	if (tx.crypt) {
516 		skb = hostap_tx_encrypt(skb, tx.crypt);
517 		if (skb == NULL) {
518 			printk(KERN_DEBUG "%s: TX - encryption failed\n",
519 			       dev->name);
520 			ret = NETDEV_TX_OK;
521 			goto fail;
522 		}
523 		meta = (struct hostap_skb_tx_data *) skb->cb;
524 		if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
525 			printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
526 			       "expected 0x%08x) after hostap_tx_encrypt\n",
527 			       dev->name, meta->magic,
528 			       HOSTAP_SKB_TX_DATA_MAGIC);
529 			ret = NETDEV_TX_OK;
530 			iface->stats.tx_dropped++;
531 			goto fail;
532 		}
533 	}
534 
535 	if (local->func->tx == NULL || local->func->tx(skb, dev)) {
536 		ret = NETDEV_TX_OK;
537 		iface->stats.tx_dropped++;
538 	} else {
539 		ret = NETDEV_TX_OK;
540 		iface->stats.tx_packets++;
541 		iface->stats.tx_bytes += skb->len;
542 	}
543 
544  fail:
545 	if (ret == NETDEV_TX_OK && skb)
546 		dev_kfree_skb(skb);
547  tx_exit:
548 	if (tx.sta_ptr)
549 		hostap_handle_sta_release(tx.sta_ptr);
550 	return ret;
551 }
552 
553 
554 EXPORT_SYMBOL(hostap_master_start_xmit);
555