xref: /openbmc/linux/net/8021q/vlan_dev.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /* -*- linux-c -*-
2  * INET		802.1Q VLAN
3  *		Ethernet-type device handling.
4  *
5  * Authors:	Ben Greear <greearb@candelatech.com>
6  *              Please send support related email to: vlan@scry.wanfear.com
7  *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
8  *
9  * Fixes:       Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
10  *                - reset skb->pkt_type on incoming packets when MAC was changed
11  *                - see that changed MAC is saddr for outgoing packets
12  *              Oct 20, 2001:  Ard van Breeman:
13  *                - Fix MC-list, finally.
14  *                - Flush MC-list on VLAN destroy.
15  *
16  *
17  *		This program is free software; you can redistribute it and/or
18  *		modify it under the terms of the GNU General Public License
19  *		as published by the Free Software Foundation; either version
20  *		2 of the License, or (at your option) any later version.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/mm.h>
25 #include <linux/in.h>
26 #include <linux/init.h>
27 #include <asm/uaccess.h> /* for copy_from_user */
28 #include <linux/skbuff.h>
29 #include <linux/netdevice.h>
30 #include <linux/etherdevice.h>
31 #include <net/datalink.h>
32 #include <net/p8022.h>
33 #include <net/arp.h>
34 
35 #include "vlan.h"
36 #include "vlanproc.h"
37 #include <linux/if_vlan.h>
38 #include <net/ip.h>
39 
40 /*
41  *	Rebuild the Ethernet MAC header. This is called after an ARP
42  *	(or in future other address resolution) has completed on this
43  *	sk_buff. We now let ARP fill in the other fields.
44  *
45  *	This routine CANNOT use cached dst->neigh!
46  *	Really, it is used only when dst->neigh is wrong.
47  *
48  * TODO:  This needs a checkup, I'm ignorant here. --BLG
49  */
50 int vlan_dev_rebuild_header(struct sk_buff *skb)
51 {
52 	struct net_device *dev = skb->dev;
53 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
54 
55 	switch (veth->h_vlan_encapsulated_proto) {
56 #ifdef CONFIG_INET
57 	case __constant_htons(ETH_P_IP):
58 
59 		/* TODO:  Confirm this will work with VLAN headers... */
60 		return arp_find(veth->h_dest, skb);
61 #endif
62 	default:
63 		printk(VLAN_DBG
64 		       "%s: unable to resolve type %X addresses.\n",
65 		       dev->name, ntohs(veth->h_vlan_encapsulated_proto));
66 
67 		memcpy(veth->h_source, dev->dev_addr, ETH_ALEN);
68 		break;
69 	}
70 
71 	return 0;
72 }
73 
74 static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
75 {
76 	if (VLAN_DEV_INFO(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
77 		if (skb_shared(skb) || skb_cloned(skb)) {
78 			struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
79 			kfree_skb(skb);
80 			skb = nskb;
81 		}
82 		if (skb) {
83 			/* Lifted from Gleb's VLAN code... */
84 			memmove(skb->data - ETH_HLEN,
85 				skb->data - VLAN_ETH_HLEN, 12);
86 			skb->mac_header += VLAN_HLEN;
87 		}
88 	}
89 
90 	return skb;
91 }
92 
93 /*
94  *	Determine the packet's protocol ID. The rule here is that we
95  *	assume 802.3 if the type field is short enough to be a length.
96  *	This is normal practice and works for any 'now in use' protocol.
97  *
98  *  Also, at this point we assume that we ARE dealing exclusively with
99  *  VLAN packets, or packets that should be made into VLAN packets based
100  *  on a default VLAN ID.
101  *
102  *  NOTE:  Should be similar to ethernet/eth.c.
103  *
104  *  SANITY NOTE:  This method is called when a packet is moving up the stack
105  *                towards userland.  To get here, it would have already passed
106  *                through the ethernet/eth.c eth_type_trans() method.
107  *  SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
108  *                 stored UNALIGNED in the memory.  RISC systems don't like
109  *                 such cases very much...
110  *  SANITY NOTE 2a:  According to Dave Miller & Alexey, it will always be aligned,
111  *                 so there doesn't need to be any of the unaligned stuff.  It has
112  *                 been commented out now...  --Ben
113  *
114  */
115 int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
116 		  struct packet_type* ptype, struct net_device *orig_dev)
117 {
118 	unsigned char *rawp = NULL;
119 	struct vlan_hdr *vhdr;
120 	unsigned short vid;
121 	struct net_device_stats *stats;
122 	unsigned short vlan_TCI;
123 	__be16 proto;
124 
125 	if (dev->nd_net != &init_net) {
126 		kfree_skb(skb);
127 		return -1;
128 	}
129 
130 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
131 		return -1;
132 
133 	if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) {
134 		kfree_skb(skb);
135 		return -1;
136 	}
137 
138 	vhdr = (struct vlan_hdr *)(skb->data);
139 
140 	/* vlan_TCI = ntohs(get_unaligned(&vhdr->h_vlan_TCI)); */
141 	vlan_TCI = ntohs(vhdr->h_vlan_TCI);
142 
143 	vid = (vlan_TCI & VLAN_VID_MASK);
144 
145 #ifdef VLAN_DEBUG
146 	printk(VLAN_DBG "%s: skb: %p vlan_id: %hx\n",
147 		__FUNCTION__, skb, vid);
148 #endif
149 
150 	/* Ok, we will find the correct VLAN device, strip the header,
151 	 * and then go on as usual.
152 	 */
153 
154 	/* We have 12 bits of vlan ID.
155 	 *
156 	 * We must not drop allow preempt until we hold a
157 	 * reference to the device (netif_rx does that) or we
158 	 * fail.
159 	 */
160 
161 	rcu_read_lock();
162 	skb->dev = __find_vlan_dev(dev, vid);
163 	if (!skb->dev) {
164 		rcu_read_unlock();
165 
166 #ifdef VLAN_DEBUG
167 		printk(VLAN_DBG "%s: ERROR: No net_device for VID: %i on dev: %s [%i]\n",
168 			__FUNCTION__, (unsigned int)(vid), dev->name, dev->ifindex);
169 #endif
170 		kfree_skb(skb);
171 		return -1;
172 	}
173 
174 	skb->dev->last_rx = jiffies;
175 
176 	/* Bump the rx counters for the VLAN device. */
177 	stats = vlan_dev_get_stats(skb->dev);
178 	stats->rx_packets++;
179 	stats->rx_bytes += skb->len;
180 
181 	/* Take off the VLAN header (4 bytes currently) */
182 	skb_pull_rcsum(skb, VLAN_HLEN);
183 
184 	/* Ok, lets check to make sure the device (dev) we
185 	 * came in on is what this VLAN is attached to.
186 	 */
187 
188 	if (dev != VLAN_DEV_INFO(skb->dev)->real_dev) {
189 		rcu_read_unlock();
190 
191 #ifdef VLAN_DEBUG
192 		printk(VLAN_DBG "%s: dropping skb: %p because came in on wrong device, dev: %s  real_dev: %s, skb_dev: %s\n",
193 			__FUNCTION__, skb, dev->name,
194 			VLAN_DEV_INFO(skb->dev)->real_dev->name,
195 			skb->dev->name);
196 #endif
197 		kfree_skb(skb);
198 		stats->rx_errors++;
199 		return -1;
200 	}
201 
202 	/*
203 	 * Deal with ingress priority mapping.
204 	 */
205 	skb->priority = vlan_get_ingress_priority(skb->dev, ntohs(vhdr->h_vlan_TCI));
206 
207 #ifdef VLAN_DEBUG
208 	printk(VLAN_DBG "%s: priority: %lu  for TCI: %hu (hbo)\n",
209 		__FUNCTION__, (unsigned long)(skb->priority),
210 		ntohs(vhdr->h_vlan_TCI));
211 #endif
212 
213 	/* The ethernet driver already did the pkt_type calculations
214 	 * for us...
215 	 */
216 	switch (skb->pkt_type) {
217 	case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
218 		// stats->broadcast ++; // no such counter :-(
219 		break;
220 
221 	case PACKET_MULTICAST:
222 		stats->multicast++;
223 		break;
224 
225 	case PACKET_OTHERHOST:
226 		/* Our lower layer thinks this is not local, let's make sure.
227 		 * This allows the VLAN to have a different MAC than the underlying
228 		 * device, and still route correctly.
229 		 */
230 		if (!compare_ether_addr(eth_hdr(skb)->h_dest, skb->dev->dev_addr)) {
231 			/* It is for our (changed) MAC-address! */
232 			skb->pkt_type = PACKET_HOST;
233 		}
234 		break;
235 	default:
236 		break;
237 	}
238 
239 	/*  Was a VLAN packet, grab the encapsulated protocol, which the layer
240 	 * three protocols care about.
241 	 */
242 	/* proto = get_unaligned(&vhdr->h_vlan_encapsulated_proto); */
243 	proto = vhdr->h_vlan_encapsulated_proto;
244 
245 	skb->protocol = proto;
246 	if (ntohs(proto) >= 1536) {
247 		/* place it back on the queue to be handled by
248 		 * true layer 3 protocols.
249 		 */
250 
251 		/* See if we are configured to re-write the VLAN header
252 		 * to make it look like ethernet...
253 		 */
254 		skb = vlan_check_reorder_header(skb);
255 
256 		/* Can be null if skb-clone fails when re-ordering */
257 		if (skb) {
258 			netif_rx(skb);
259 		} else {
260 			/* TODO:  Add a more specific counter here. */
261 			stats->rx_errors++;
262 		}
263 		rcu_read_unlock();
264 		return 0;
265 	}
266 
267 	rawp = skb->data;
268 
269 	/*
270 	 * This is a magic hack to spot IPX packets. Older Novell breaks
271 	 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
272 	 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
273 	 * won't work for fault tolerant netware but does for the rest.
274 	 */
275 	if (*(unsigned short *)rawp == 0xFFFF) {
276 		skb->protocol = htons(ETH_P_802_3);
277 		/* place it back on the queue to be handled by true layer 3 protocols.
278 		 */
279 
280 		/* See if we are configured to re-write the VLAN header
281 		 * to make it look like ethernet...
282 		 */
283 		skb = vlan_check_reorder_header(skb);
284 
285 		/* Can be null if skb-clone fails when re-ordering */
286 		if (skb) {
287 			netif_rx(skb);
288 		} else {
289 			/* TODO:  Add a more specific counter here. */
290 			stats->rx_errors++;
291 		}
292 		rcu_read_unlock();
293 		return 0;
294 	}
295 
296 	/*
297 	 *	Real 802.2 LLC
298 	 */
299 	skb->protocol = htons(ETH_P_802_2);
300 	/* place it back on the queue to be handled by upper layer protocols.
301 	 */
302 
303 	/* See if we are configured to re-write the VLAN header
304 	 * to make it look like ethernet...
305 	 */
306 	skb = vlan_check_reorder_header(skb);
307 
308 	/* Can be null if skb-clone fails when re-ordering */
309 	if (skb) {
310 		netif_rx(skb);
311 	} else {
312 		/* TODO:  Add a more specific counter here. */
313 		stats->rx_errors++;
314 	}
315 	rcu_read_unlock();
316 	return 0;
317 }
318 
319 static inline unsigned short vlan_dev_get_egress_qos_mask(struct net_device* dev,
320 							  struct sk_buff* skb)
321 {
322 	struct vlan_priority_tci_mapping *mp =
323 		VLAN_DEV_INFO(dev)->egress_priority_map[(skb->priority & 0xF)];
324 
325 	while (mp) {
326 		if (mp->priority == skb->priority) {
327 			return mp->vlan_qos; /* This should already be shifted to mask
328 					      * correctly with the VLAN's TCI
329 					      */
330 		}
331 		mp = mp->next;
332 	}
333 	return 0;
334 }
335 
336 /*
337  *	Create the VLAN header for an arbitrary protocol layer
338  *
339  *	saddr=NULL	means use device source address
340  *	daddr=NULL	means leave destination address (eg unresolved arp)
341  *
342  *  This is called when the SKB is moving down the stack towards the
343  *  physical devices.
344  */
345 int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
346 			 unsigned short type,
347 			 const void *daddr, const void *saddr, unsigned len)
348 {
349 	struct vlan_hdr *vhdr;
350 	unsigned short veth_TCI = 0;
351 	int rc = 0;
352 	int build_vlan_header = 0;
353 	struct net_device *vdev = dev; /* save this for the bottom of the method */
354 
355 #ifdef VLAN_DEBUG
356 	printk(VLAN_DBG "%s: skb: %p type: %hx len: %x vlan_id: %hx, daddr: %p\n",
357 		__FUNCTION__, skb, type, len, VLAN_DEV_INFO(dev)->vlan_id, daddr);
358 #endif
359 
360 	/* build vlan header only if re_order_header flag is NOT set.  This
361 	 * fixes some programs that get confused when they see a VLAN device
362 	 * sending a frame that is VLAN encoded (the consensus is that the VLAN
363 	 * device should look completely like an Ethernet device when the
364 	 * REORDER_HEADER flag is set)	The drawback to this is some extra
365 	 * header shuffling in the hard_start_xmit.  Users can turn off this
366 	 * REORDER behaviour with the vconfig tool.
367 	 */
368 	if (!(VLAN_DEV_INFO(dev)->flags & VLAN_FLAG_REORDER_HDR))
369 		build_vlan_header = 1;
370 
371 	if (build_vlan_header) {
372 		vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
373 
374 		/* build the four bytes that make this a VLAN header. */
375 
376 		/* Now, construct the second two bytes. This field looks something
377 		 * like:
378 		 * usr_priority: 3 bits	 (high bits)
379 		 * CFI		 1 bit
380 		 * VLAN ID	 12 bits (low bits)
381 		 *
382 		 */
383 		veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
384 		veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
385 
386 		vhdr->h_vlan_TCI = htons(veth_TCI);
387 
388 		/*
389 		 *  Set the protocol type.
390 		 *  For a packet of type ETH_P_802_3 we put the length in here instead.
391 		 *  It is up to the 802.2 layer to carry protocol information.
392 		 */
393 
394 		if (type != ETH_P_802_3) {
395 			vhdr->h_vlan_encapsulated_proto = htons(type);
396 		} else {
397 			vhdr->h_vlan_encapsulated_proto = htons(len);
398 		}
399 
400 		skb->protocol = htons(ETH_P_8021Q);
401 		skb_reset_network_header(skb);
402 	}
403 
404 	/* Before delegating work to the lower layer, enter our MAC-address */
405 	if (saddr == NULL)
406 		saddr = dev->dev_addr;
407 
408 	dev = VLAN_DEV_INFO(dev)->real_dev;
409 
410 	/* MPLS can send us skbuffs w/out enough space.	 This check will grow the
411 	 * skb if it doesn't have enough headroom.  Not a beautiful solution, so
412 	 * I'll tick a counter so that users can know it's happening...	 If they
413 	 * care...
414 	 */
415 
416 	/* NOTE:  This may still break if the underlying device is not the final
417 	 * device (and thus there are more headers to add...)  It should work for
418 	 * good-ole-ethernet though.
419 	 */
420 	if (skb_headroom(skb) < dev->hard_header_len) {
421 		struct sk_buff *sk_tmp = skb;
422 		skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
423 		kfree_skb(sk_tmp);
424 		if (skb == NULL) {
425 			struct net_device_stats *stats = vlan_dev_get_stats(vdev);
426 			stats->tx_dropped++;
427 			return -ENOMEM;
428 		}
429 		VLAN_DEV_INFO(vdev)->cnt_inc_headroom_on_tx++;
430 #ifdef VLAN_DEBUG
431 		printk(VLAN_DBG "%s: %s: had to grow skb.\n", __FUNCTION__, vdev->name);
432 #endif
433 	}
434 
435 	if (build_vlan_header) {
436 		/* Now make the underlying real hard header */
437 		rc = dev_hard_header(skb, dev, ETH_P_8021Q, daddr, saddr,
438 				     len + VLAN_HLEN);
439 		if (rc > 0)
440 			rc += VLAN_HLEN;
441 		else if (rc < 0)
442 			rc -= VLAN_HLEN;
443 	} else
444 		/* If here, then we'll just make a normal looking ethernet frame,
445 		 * but, the hard_start_xmit method will insert the tag (it has to
446 		 * be able to do this for bridged and other skbs that don't come
447 		 * down the protocol stack in an orderly manner.
448 		 */
449 		rc = dev_hard_header(skb, dev, type, daddr, saddr, len);
450 
451 	return rc;
452 }
453 
454 int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
455 {
456 	struct net_device_stats *stats = vlan_dev_get_stats(dev);
457 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
458 
459 	/* Handle non-VLAN frames if they are sent to us, for example by DHCP.
460 	 *
461 	 * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
462 	 * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
463 	 */
464 
465 	if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
466 		int orig_headroom = skb_headroom(skb);
467 		unsigned short veth_TCI;
468 
469 		/* This is not a VLAN frame...but we can fix that! */
470 		VLAN_DEV_INFO(dev)->cnt_encap_on_xmit++;
471 
472 #ifdef VLAN_DEBUG
473 		printk(VLAN_DBG "%s: proto to encap: 0x%hx (hbo)\n",
474 			__FUNCTION__, htons(veth->h_vlan_proto));
475 #endif
476 		/* Construct the second two bytes. This field looks something
477 		 * like:
478 		 * usr_priority: 3 bits	 (high bits)
479 		 * CFI		 1 bit
480 		 * VLAN ID	 12 bits (low bits)
481 		 */
482 		veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
483 		veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
484 
485 		skb = __vlan_put_tag(skb, veth_TCI);
486 		if (!skb) {
487 			stats->tx_dropped++;
488 			return 0;
489 		}
490 
491 		if (orig_headroom < VLAN_HLEN) {
492 			VLAN_DEV_INFO(dev)->cnt_inc_headroom_on_tx++;
493 		}
494 	}
495 
496 #ifdef VLAN_DEBUG
497 	printk(VLAN_DBG "%s: about to send skb: %p to dev: %s\n",
498 		__FUNCTION__, skb, skb->dev->name);
499 	printk(VLAN_DBG "  %2hx.%2hx.%2hx.%2xh.%2hx.%2hx %2hx.%2hx.%2hx.%2hx.%2hx.%2hx %4hx %4hx %4hx\n",
500 	       veth->h_dest[0], veth->h_dest[1], veth->h_dest[2], veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
501 	       veth->h_source[0], veth->h_source[1], veth->h_source[2], veth->h_source[3], veth->h_source[4], veth->h_source[5],
502 	       veth->h_vlan_proto, veth->h_vlan_TCI, veth->h_vlan_encapsulated_proto);
503 #endif
504 
505 	stats->tx_packets++; /* for statics only */
506 	stats->tx_bytes += skb->len;
507 
508 	skb->dev = VLAN_DEV_INFO(dev)->real_dev;
509 	dev_queue_xmit(skb);
510 
511 	return 0;
512 }
513 
514 int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
515 {
516 	struct net_device_stats *stats = vlan_dev_get_stats(dev);
517 	unsigned short veth_TCI;
518 
519 	/* Construct the second two bytes. This field looks something
520 	 * like:
521 	 * usr_priority: 3 bits	 (high bits)
522 	 * CFI		 1 bit
523 	 * VLAN ID	 12 bits (low bits)
524 	 */
525 	veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
526 	veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
527 	skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
528 
529 	stats->tx_packets++;
530 	stats->tx_bytes += skb->len;
531 
532 	skb->dev = VLAN_DEV_INFO(dev)->real_dev;
533 	dev_queue_xmit(skb);
534 
535 	return 0;
536 }
537 
538 int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
539 {
540 	/* TODO: gotta make sure the underlying layer can handle it,
541 	 * maybe an IFF_VLAN_CAPABLE flag for devices?
542 	 */
543 	if (VLAN_DEV_INFO(dev)->real_dev->mtu < new_mtu)
544 		return -ERANGE;
545 
546 	dev->mtu = new_mtu;
547 
548 	return 0;
549 }
550 
551 void vlan_dev_set_ingress_priority(const struct net_device *dev,
552 				   u32 skb_prio, short vlan_prio)
553 {
554 	struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev);
555 
556 	if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio)
557 		vlan->nr_ingress_mappings--;
558 	else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio)
559 		vlan->nr_ingress_mappings++;
560 
561 	vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
562 }
563 
564 int vlan_dev_set_egress_priority(const struct net_device *dev,
565 				 u32 skb_prio, short vlan_prio)
566 {
567 	struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev);
568 	struct vlan_priority_tci_mapping *mp = NULL;
569 	struct vlan_priority_tci_mapping *np;
570 	u32 vlan_qos = (vlan_prio << 13) & 0xE000;
571 
572 	/* See if a priority mapping exists.. */
573 	mp = vlan->egress_priority_map[skb_prio & 0xF];
574 	while (mp) {
575 		if (mp->priority == skb_prio) {
576 			if (mp->vlan_qos && !vlan_qos)
577 				vlan->nr_egress_mappings--;
578 			else if (!mp->vlan_qos && vlan_qos)
579 				vlan->nr_egress_mappings++;
580 			mp->vlan_qos = vlan_qos;
581 			return 0;
582 		}
583 		mp = mp->next;
584 	}
585 
586 	/* Create a new mapping then. */
587 	mp = vlan->egress_priority_map[skb_prio & 0xF];
588 	np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
589 	if (!np)
590 		return -ENOBUFS;
591 
592 	np->next = mp;
593 	np->priority = skb_prio;
594 	np->vlan_qos = vlan_qos;
595 	vlan->egress_priority_map[skb_prio & 0xF] = np;
596 	if (vlan_qos)
597 		vlan->nr_egress_mappings++;
598 	return 0;
599 }
600 
601 /* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */
602 int vlan_dev_set_vlan_flag(const struct net_device *dev,
603 			   u32 flag, short flag_val)
604 {
605 	/* verify flag is supported */
606 	if (flag == VLAN_FLAG_REORDER_HDR) {
607 		if (flag_val) {
608 			VLAN_DEV_INFO(dev)->flags |= VLAN_FLAG_REORDER_HDR;
609 		} else {
610 			VLAN_DEV_INFO(dev)->flags &= ~VLAN_FLAG_REORDER_HDR;
611 		}
612 		return 0;
613 	}
614 	printk(KERN_ERR "%s: flag %i is not valid.\n", __FUNCTION__, flag);
615 	return -EINVAL;
616 }
617 
618 void vlan_dev_get_realdev_name(const struct net_device *dev, char *result)
619 {
620 	strncpy(result, VLAN_DEV_INFO(dev)->real_dev->name, 23);
621 }
622 
623 void vlan_dev_get_vid(const struct net_device *dev, unsigned short *result)
624 {
625 	*result = VLAN_DEV_INFO(dev)->vlan_id;
626 }
627 
628 int vlan_dev_open(struct net_device *dev)
629 {
630 	struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev);
631 	struct net_device *real_dev = vlan->real_dev;
632 	int err;
633 
634 	if (!(real_dev->flags & IFF_UP))
635 		return -ENETDOWN;
636 
637 	if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) {
638 		err = dev_unicast_add(real_dev, dev->dev_addr, ETH_ALEN);
639 		if (err < 0)
640 			return err;
641 	}
642 	memcpy(vlan->real_dev_addr, real_dev->dev_addr, ETH_ALEN);
643 
644 	if (dev->flags & IFF_ALLMULTI)
645 		dev_set_allmulti(real_dev, 1);
646 	if (dev->flags & IFF_PROMISC)
647 		dev_set_promiscuity(real_dev, 1);
648 
649 	return 0;
650 }
651 
652 int vlan_dev_stop(struct net_device *dev)
653 {
654 	struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev;
655 
656 	dev_mc_unsync(real_dev, dev);
657 	if (dev->flags & IFF_ALLMULTI)
658 		dev_set_allmulti(real_dev, -1);
659 	if (dev->flags & IFF_PROMISC)
660 		dev_set_promiscuity(real_dev, -1);
661 
662 	if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
663 		dev_unicast_delete(real_dev, dev->dev_addr, dev->addr_len);
664 
665 	return 0;
666 }
667 
668 int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
669 {
670 	struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev;
671 	struct ifreq ifrr;
672 	int err = -EOPNOTSUPP;
673 
674 	strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
675 	ifrr.ifr_ifru = ifr->ifr_ifru;
676 
677 	switch(cmd) {
678 	case SIOCGMIIPHY:
679 	case SIOCGMIIREG:
680 	case SIOCSMIIREG:
681 		if (real_dev->do_ioctl && netif_device_present(real_dev))
682 			err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
683 		break;
684 	}
685 
686 	if (!err)
687 		ifr->ifr_ifru = ifrr.ifr_ifru;
688 
689 	return err;
690 }
691 
692 void vlan_change_rx_flags(struct net_device *dev, int change)
693 {
694 	struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev;
695 
696 	if (change & IFF_ALLMULTI)
697 		dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1);
698 	if (change & IFF_PROMISC)
699 		dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1);
700 }
701 
702 /** Taken from Gleb + Lennert's VLAN code, and modified... */
703 void vlan_dev_set_multicast_list(struct net_device *vlan_dev)
704 {
705 	dev_mc_sync(VLAN_DEV_INFO(vlan_dev)->real_dev, vlan_dev);
706 }
707