3 * Ethernet-type device handling.
5 * Authors: Ben Greear <greearb@candelatech.com>
6 * Please send support related email to: netdev@vger.kernel.org
7 * VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
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.
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.
23 #include <linux/module.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>
37 #include <linux/if_vlan.h>
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.
45 * This routine CANNOT use cached dst->neigh!
46 * Really, it is used only when dst->neigh is wrong.
48 * TODO: This needs a checkup, I'm ignorant here. --BLG
50 static int vlan_dev_rebuild_header(struct sk_buff
*skb
)
52 struct net_device
*dev
= skb
->dev
;
53 struct vlan_ethhdr
*veth
= (struct vlan_ethhdr
*)(skb
->data
);
55 switch (veth
->h_vlan_encapsulated_proto
) {
57 case __constant_htons(ETH_P_IP
):
59 /* TODO: Confirm this will work with VLAN headers... */
60 return arp_find(veth
->h_dest
, skb
);
63 pr_debug("%s: unable to resolve type %X addresses.\n",
64 dev
->name
, ntohs(veth
->h_vlan_encapsulated_proto
));
66 memcpy(veth
->h_source
, dev
->dev_addr
, ETH_ALEN
);
73 static inline struct sk_buff
*vlan_check_reorder_header(struct sk_buff
*skb
)
75 if (vlan_dev_info(skb
->dev
)->flags
& VLAN_FLAG_REORDER_HDR
) {
76 if (skb_shared(skb
) || skb_cloned(skb
)) {
77 struct sk_buff
*nskb
= skb_copy(skb
, GFP_ATOMIC
);
82 /* Lifted from Gleb's VLAN code... */
83 memmove(skb
->data
- ETH_HLEN
,
84 skb
->data
- VLAN_ETH_HLEN
, 12);
85 skb
->mac_header
+= VLAN_HLEN
;
92 static inline void vlan_set_encap_proto(struct sk_buff
*skb
,
93 struct vlan_hdr
*vhdr
)
99 * Was a VLAN packet, grab the encapsulated protocol, which the layer
100 * three protocols care about.
103 proto
= vhdr
->h_vlan_encapsulated_proto
;
104 if (ntohs(proto
) >= 1536) {
105 skb
->protocol
= proto
;
110 if (*(unsigned short *)rawp
== 0xFFFF)
112 * This is a magic hack to spot IPX packets. Older Novell
113 * breaks the protocol design and runs IPX over 802.3 without
114 * an 802.2 LLC layer. We look for FFFF which isn't a used
115 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
116 * but does for the rest.
118 skb
->protocol
= htons(ETH_P_802_3
);
123 skb
->protocol
= htons(ETH_P_802_2
);
127 * Determine the packet's protocol ID. The rule here is that we
128 * assume 802.3 if the type field is short enough to be a length.
129 * This is normal practice and works for any 'now in use' protocol.
131 * Also, at this point we assume that we ARE dealing exclusively with
132 * VLAN packets, or packets that should be made into VLAN packets based
133 * on a default VLAN ID.
135 * NOTE: Should be similar to ethernet/eth.c.
137 * SANITY NOTE: This method is called when a packet is moving up the stack
138 * towards userland. To get here, it would have already passed
139 * through the ethernet/eth.c eth_type_trans() method.
140 * SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
141 * stored UNALIGNED in the memory. RISC systems don't like
142 * such cases very much...
143 * SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be
144 * aligned, so there doesn't need to be any of the unaligned
145 * stuff. It has been commented out now... --Ben
148 int vlan_skb_recv(struct sk_buff
*skb
, struct net_device
*dev
,
149 struct packet_type
*ptype
, struct net_device
*orig_dev
)
151 struct vlan_hdr
*vhdr
;
153 struct net_device_stats
*stats
;
154 unsigned short vlan_TCI
;
156 if (dev_net(dev
) != &init_net
)
159 skb
= skb_share_check(skb
, GFP_ATOMIC
);
163 if (unlikely(!pskb_may_pull(skb
, VLAN_HLEN
)))
166 vhdr
= (struct vlan_hdr
*)skb
->data
;
167 vlan_TCI
= ntohs(vhdr
->h_vlan_TCI
);
168 vid
= (vlan_TCI
& VLAN_VID_MASK
);
171 skb
->dev
= __find_vlan_dev(dev
, vid
);
173 pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
174 __func__
, (unsigned int)vid
, dev
->name
);
178 skb
->dev
->last_rx
= jiffies
;
180 stats
= &skb
->dev
->stats
;
182 stats
->rx_bytes
+= skb
->len
;
184 skb_pull_rcsum(skb
, VLAN_HLEN
);
186 skb
->priority
= vlan_get_ingress_priority(skb
->dev
,
187 ntohs(vhdr
->h_vlan_TCI
));
189 pr_debug("%s: priority: %u for TCI: %hu\n",
190 __func__
, skb
->priority
, ntohs(vhdr
->h_vlan_TCI
));
192 switch (skb
->pkt_type
) {
193 case PACKET_BROADCAST
: /* Yeah, stats collect these together.. */
194 /* stats->broadcast ++; // no such counter :-( */
197 case PACKET_MULTICAST
:
201 case PACKET_OTHERHOST
:
202 /* Our lower layer thinks this is not local, let's make sure.
203 * This allows the VLAN to have a different MAC than the
204 * underlying device, and still route correctly.
206 if (!compare_ether_addr(eth_hdr(skb
)->h_dest
,
208 skb
->pkt_type
= PACKET_HOST
;
214 vlan_set_encap_proto(skb
, vhdr
);
216 skb
= vlan_check_reorder_header(skb
);
224 return NET_RX_SUCCESS
;
233 static inline unsigned short
234 vlan_dev_get_egress_qos_mask(struct net_device
*dev
, struct sk_buff
*skb
)
236 struct vlan_priority_tci_mapping
*mp
;
238 mp
= vlan_dev_info(dev
)->egress_priority_map
[(skb
->priority
& 0xF)];
240 if (mp
->priority
== skb
->priority
) {
241 return mp
->vlan_qos
; /* This should already be shifted
242 * to mask correctly with the
251 * Create the VLAN header for an arbitrary protocol layer
253 * saddr=NULL means use device source address
254 * daddr=NULL means leave destination address (eg unresolved arp)
256 * This is called when the SKB is moving down the stack towards the
259 static int vlan_dev_hard_header(struct sk_buff
*skb
, struct net_device
*dev
,
261 const void *daddr
, const void *saddr
,
264 struct vlan_hdr
*vhdr
;
265 unsigned short veth_TCI
= 0;
267 int build_vlan_header
= 0;
268 struct net_device
*vdev
= dev
;
270 pr_debug("%s: skb: %p type: %hx len: %u vlan_id: %hx, daddr: %p\n",
271 __func__
, skb
, type
, len
, vlan_dev_info(dev
)->vlan_id
,
274 /* build vlan header only if re_order_header flag is NOT set. This
275 * fixes some programs that get confused when they see a VLAN device
276 * sending a frame that is VLAN encoded (the consensus is that the VLAN
277 * device should look completely like an Ethernet device when the
278 * REORDER_HEADER flag is set) The drawback to this is some extra
279 * header shuffling in the hard_start_xmit. Users can turn off this
280 * REORDER behaviour with the vconfig tool.
282 if (!(vlan_dev_info(dev
)->flags
& VLAN_FLAG_REORDER_HDR
))
283 build_vlan_header
= 1;
285 if (build_vlan_header
) {
286 vhdr
= (struct vlan_hdr
*) skb_push(skb
, VLAN_HLEN
);
288 /* build the four bytes that make this a VLAN header. */
290 /* Now, construct the second two bytes. This field looks
292 * usr_priority: 3 bits (high bits)
294 * VLAN ID 12 bits (low bits)
297 veth_TCI
= vlan_dev_info(dev
)->vlan_id
;
298 veth_TCI
|= vlan_dev_get_egress_qos_mask(dev
, skb
);
300 vhdr
->h_vlan_TCI
= htons(veth_TCI
);
303 * Set the protocol type. For a packet of type ETH_P_802_3 we
304 * put the length in here instead. It is up to the 802.2
305 * layer to carry protocol information.
308 if (type
!= ETH_P_802_3
)
309 vhdr
->h_vlan_encapsulated_proto
= htons(type
);
311 vhdr
->h_vlan_encapsulated_proto
= htons(len
);
313 skb
->protocol
= htons(ETH_P_8021Q
);
314 skb_reset_network_header(skb
);
317 /* Before delegating work to the lower layer, enter our MAC-address */
319 saddr
= dev
->dev_addr
;
321 dev
= vlan_dev_info(dev
)->real_dev
;
323 /* MPLS can send us skbuffs w/out enough space. This check will grow
324 * the skb if it doesn't have enough headroom. Not a beautiful solution,
325 * so I'll tick a counter so that users can know it's happening...
329 /* NOTE: This may still break if the underlying device is not the final
330 * device (and thus there are more headers to add...) It should work for
331 * good-ole-ethernet though.
333 if (skb_headroom(skb
) < dev
->hard_header_len
) {
334 struct sk_buff
*sk_tmp
= skb
;
335 skb
= skb_realloc_headroom(sk_tmp
, dev
->hard_header_len
);
338 struct net_device_stats
*stats
= &vdev
->stats
;
342 vlan_dev_info(vdev
)->cnt_inc_headroom_on_tx
++;
343 pr_debug("%s: %s: had to grow skb\n", __func__
, vdev
->name
);
346 if (build_vlan_header
) {
347 /* Now make the underlying real hard header */
348 rc
= dev_hard_header(skb
, dev
, ETH_P_8021Q
, daddr
, saddr
,
355 /* If here, then we'll just make a normal looking ethernet
356 * frame, but, the hard_start_xmit method will insert the tag
357 * (it has to be able to do this for bridged and other skbs
358 * that don't come down the protocol stack in an orderly manner.
360 rc
= dev_hard_header(skb
, dev
, type
, daddr
, saddr
, len
);
365 static int vlan_dev_hard_start_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
367 struct net_device_stats
*stats
= &dev
->stats
;
368 struct vlan_ethhdr
*veth
= (struct vlan_ethhdr
*)(skb
->data
);
370 /* Handle non-VLAN frames if they are sent to us, for example by DHCP.
372 * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
373 * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
376 if (veth
->h_vlan_proto
!= htons(ETH_P_8021Q
) ||
377 vlan_dev_info(dev
)->flags
& VLAN_FLAG_REORDER_HDR
) {
378 int orig_headroom
= skb_headroom(skb
);
379 unsigned short veth_TCI
;
381 /* This is not a VLAN frame...but we can fix that! */
382 vlan_dev_info(dev
)->cnt_encap_on_xmit
++;
384 pr_debug("%s: proto to encap: 0x%hx\n",
385 __func__
, ntohs(veth
->h_vlan_proto
));
386 /* Construct the second two bytes. This field looks something
388 * usr_priority: 3 bits (high bits)
390 * VLAN ID 12 bits (low bits)
392 veth_TCI
= vlan_dev_info(dev
)->vlan_id
;
393 veth_TCI
|= vlan_dev_get_egress_qos_mask(dev
, skb
);
395 skb
= __vlan_put_tag(skb
, veth_TCI
);
401 if (orig_headroom
< VLAN_HLEN
)
402 vlan_dev_info(dev
)->cnt_inc_headroom_on_tx
++;
405 pr_debug("%s: about to send skb: %p to dev: %s\n",
406 __func__
, skb
, skb
->dev
->name
);
407 pr_debug(" " MAC_FMT
" " MAC_FMT
" %4hx %4hx %4hx\n",
408 veth
->h_dest
[0], veth
->h_dest
[1], veth
->h_dest
[2],
409 veth
->h_dest
[3], veth
->h_dest
[4], veth
->h_dest
[5],
410 veth
->h_source
[0], veth
->h_source
[1], veth
->h_source
[2],
411 veth
->h_source
[3], veth
->h_source
[4], veth
->h_source
[5],
412 veth
->h_vlan_proto
, veth
->h_vlan_TCI
,
413 veth
->h_vlan_encapsulated_proto
);
415 stats
->tx_packets
++; /* for statics only */
416 stats
->tx_bytes
+= skb
->len
;
418 skb
->dev
= vlan_dev_info(dev
)->real_dev
;
424 static int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff
*skb
,
425 struct net_device
*dev
)
427 struct net_device_stats
*stats
= &dev
->stats
;
428 unsigned short veth_TCI
;
430 /* Construct the second two bytes. This field looks something
432 * usr_priority: 3 bits (high bits)
434 * VLAN ID 12 bits (low bits)
436 veth_TCI
= vlan_dev_info(dev
)->vlan_id
;
437 veth_TCI
|= vlan_dev_get_egress_qos_mask(dev
, skb
);
438 skb
= __vlan_hwaccel_put_tag(skb
, veth_TCI
);
441 stats
->tx_bytes
+= skb
->len
;
443 skb
->dev
= vlan_dev_info(dev
)->real_dev
;
449 static int vlan_dev_change_mtu(struct net_device
*dev
, int new_mtu
)
451 /* TODO: gotta make sure the underlying layer can handle it,
452 * maybe an IFF_VLAN_CAPABLE flag for devices?
454 if (vlan_dev_info(dev
)->real_dev
->mtu
< new_mtu
)
462 void vlan_dev_set_ingress_priority(const struct net_device
*dev
,
463 u32 skb_prio
, short vlan_prio
)
465 struct vlan_dev_info
*vlan
= vlan_dev_info(dev
);
467 if (vlan
->ingress_priority_map
[vlan_prio
& 0x7] && !skb_prio
)
468 vlan
->nr_ingress_mappings
--;
469 else if (!vlan
->ingress_priority_map
[vlan_prio
& 0x7] && skb_prio
)
470 vlan
->nr_ingress_mappings
++;
472 vlan
->ingress_priority_map
[vlan_prio
& 0x7] = skb_prio
;
475 int vlan_dev_set_egress_priority(const struct net_device
*dev
,
476 u32 skb_prio
, short vlan_prio
)
478 struct vlan_dev_info
*vlan
= vlan_dev_info(dev
);
479 struct vlan_priority_tci_mapping
*mp
= NULL
;
480 struct vlan_priority_tci_mapping
*np
;
481 u32 vlan_qos
= (vlan_prio
<< 13) & 0xE000;
483 /* See if a priority mapping exists.. */
484 mp
= vlan
->egress_priority_map
[skb_prio
& 0xF];
486 if (mp
->priority
== skb_prio
) {
487 if (mp
->vlan_qos
&& !vlan_qos
)
488 vlan
->nr_egress_mappings
--;
489 else if (!mp
->vlan_qos
&& vlan_qos
)
490 vlan
->nr_egress_mappings
++;
491 mp
->vlan_qos
= vlan_qos
;
497 /* Create a new mapping then. */
498 mp
= vlan
->egress_priority_map
[skb_prio
& 0xF];
499 np
= kmalloc(sizeof(struct vlan_priority_tci_mapping
), GFP_KERNEL
);
504 np
->priority
= skb_prio
;
505 np
->vlan_qos
= vlan_qos
;
506 vlan
->egress_priority_map
[skb_prio
& 0xF] = np
;
508 vlan
->nr_egress_mappings
++;
512 /* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */
513 int vlan_dev_set_vlan_flag(const struct net_device
*dev
,
514 u32 flag
, short flag_val
)
516 /* verify flag is supported */
517 if (flag
== VLAN_FLAG_REORDER_HDR
) {
519 vlan_dev_info(dev
)->flags
|= VLAN_FLAG_REORDER_HDR
;
521 vlan_dev_info(dev
)->flags
&= ~VLAN_FLAG_REORDER_HDR
;
527 void vlan_dev_get_realdev_name(const struct net_device
*dev
, char *result
)
529 strncpy(result
, vlan_dev_info(dev
)->real_dev
->name
, 23);
532 void vlan_dev_get_vid(const struct net_device
*dev
, unsigned short *result
)
534 *result
= vlan_dev_info(dev
)->vlan_id
;
537 static int vlan_dev_open(struct net_device
*dev
)
539 struct vlan_dev_info
*vlan
= vlan_dev_info(dev
);
540 struct net_device
*real_dev
= vlan
->real_dev
;
543 if (!(real_dev
->flags
& IFF_UP
))
546 if (compare_ether_addr(dev
->dev_addr
, real_dev
->dev_addr
)) {
547 err
= dev_unicast_add(real_dev
, dev
->dev_addr
, ETH_ALEN
);
551 memcpy(vlan
->real_dev_addr
, real_dev
->dev_addr
, ETH_ALEN
);
553 if (dev
->flags
& IFF_ALLMULTI
)
554 dev_set_allmulti(real_dev
, 1);
555 if (dev
->flags
& IFF_PROMISC
)
556 dev_set_promiscuity(real_dev
, 1);
561 static int vlan_dev_stop(struct net_device
*dev
)
563 struct net_device
*real_dev
= vlan_dev_info(dev
)->real_dev
;
565 dev_mc_unsync(real_dev
, dev
);
566 dev_unicast_unsync(real_dev
, dev
);
567 if (dev
->flags
& IFF_ALLMULTI
)
568 dev_set_allmulti(real_dev
, -1);
569 if (dev
->flags
& IFF_PROMISC
)
570 dev_set_promiscuity(real_dev
, -1);
572 if (compare_ether_addr(dev
->dev_addr
, real_dev
->dev_addr
))
573 dev_unicast_delete(real_dev
, dev
->dev_addr
, dev
->addr_len
);
578 static int vlan_dev_set_mac_address(struct net_device
*dev
, void *p
)
580 struct net_device
*real_dev
= vlan_dev_info(dev
)->real_dev
;
581 struct sockaddr
*addr
= p
;
584 if (!is_valid_ether_addr(addr
->sa_data
))
585 return -EADDRNOTAVAIL
;
587 if (!(dev
->flags
& IFF_UP
))
590 if (compare_ether_addr(addr
->sa_data
, real_dev
->dev_addr
)) {
591 err
= dev_unicast_add(real_dev
, addr
->sa_data
, ETH_ALEN
);
596 if (compare_ether_addr(dev
->dev_addr
, real_dev
->dev_addr
))
597 dev_unicast_delete(real_dev
, dev
->dev_addr
, ETH_ALEN
);
600 memcpy(dev
->dev_addr
, addr
->sa_data
, ETH_ALEN
);
604 static int vlan_dev_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
606 struct net_device
*real_dev
= vlan_dev_info(dev
)->real_dev
;
608 int err
= -EOPNOTSUPP
;
610 strncpy(ifrr
.ifr_name
, real_dev
->name
, IFNAMSIZ
);
611 ifrr
.ifr_ifru
= ifr
->ifr_ifru
;
617 if (real_dev
->do_ioctl
&& netif_device_present(real_dev
))
618 err
= real_dev
->do_ioctl(real_dev
, &ifrr
, cmd
);
623 ifr
->ifr_ifru
= ifrr
.ifr_ifru
;
628 static void vlan_dev_change_rx_flags(struct net_device
*dev
, int change
)
630 struct net_device
*real_dev
= vlan_dev_info(dev
)->real_dev
;
632 if (change
& IFF_ALLMULTI
)
633 dev_set_allmulti(real_dev
, dev
->flags
& IFF_ALLMULTI
? 1 : -1);
634 if (change
& IFF_PROMISC
)
635 dev_set_promiscuity(real_dev
, dev
->flags
& IFF_PROMISC
? 1 : -1);
638 static void vlan_dev_set_rx_mode(struct net_device
*vlan_dev
)
640 dev_mc_sync(vlan_dev_info(vlan_dev
)->real_dev
, vlan_dev
);
641 dev_unicast_sync(vlan_dev_info(vlan_dev
)->real_dev
, vlan_dev
);
645 * vlan network devices have devices nesting below it, and are a special
646 * "super class" of normal network devices; split their locks off into a
647 * separate class since they always nest.
649 static struct lock_class_key vlan_netdev_xmit_lock_key
;
651 static const struct header_ops vlan_header_ops
= {
652 .create
= vlan_dev_hard_header
,
653 .rebuild
= vlan_dev_rebuild_header
,
654 .parse
= eth_header_parse
,
657 static int vlan_dev_init(struct net_device
*dev
)
659 struct net_device
*real_dev
= vlan_dev_info(dev
)->real_dev
;
662 /* IFF_BROADCAST|IFF_MULTICAST; ??? */
663 dev
->flags
= real_dev
->flags
& ~IFF_UP
;
664 dev
->iflink
= real_dev
->ifindex
;
665 dev
->state
= (real_dev
->state
& ((1<<__LINK_STATE_NOCARRIER
) |
666 (1<<__LINK_STATE_DORMANT
))) |
667 (1<<__LINK_STATE_PRESENT
);
669 /* ipv6 shared card related stuff */
670 dev
->dev_id
= real_dev
->dev_id
;
672 if (is_zero_ether_addr(dev
->dev_addr
))
673 memcpy(dev
->dev_addr
, real_dev
->dev_addr
, dev
->addr_len
);
674 if (is_zero_ether_addr(dev
->broadcast
))
675 memcpy(dev
->broadcast
, real_dev
->broadcast
, dev
->addr_len
);
677 if (real_dev
->features
& NETIF_F_HW_VLAN_TX
) {
678 dev
->header_ops
= real_dev
->header_ops
;
679 dev
->hard_header_len
= real_dev
->hard_header_len
;
680 dev
->hard_start_xmit
= vlan_dev_hwaccel_hard_start_xmit
;
682 dev
->header_ops
= &vlan_header_ops
;
683 dev
->hard_header_len
= real_dev
->hard_header_len
+ VLAN_HLEN
;
684 dev
->hard_start_xmit
= vlan_dev_hard_start_xmit
;
687 if (real_dev
->priv_flags
& IFF_802_1Q_VLAN
)
690 lockdep_set_class_and_subclass(&dev
->_xmit_lock
,
691 &vlan_netdev_xmit_lock_key
, subclass
);
695 void vlan_setup(struct net_device
*dev
)
699 dev
->priv_flags
|= IFF_802_1Q_VLAN
;
700 dev
->tx_queue_len
= 0;
702 dev
->change_mtu
= vlan_dev_change_mtu
;
703 dev
->init
= vlan_dev_init
;
704 dev
->open
= vlan_dev_open
;
705 dev
->stop
= vlan_dev_stop
;
706 dev
->set_mac_address
= vlan_dev_set_mac_address
;
707 dev
->set_rx_mode
= vlan_dev_set_rx_mode
;
708 dev
->set_multicast_list
= vlan_dev_set_rx_mode
;
709 dev
->change_rx_flags
= vlan_dev_change_rx_flags
;
710 dev
->do_ioctl
= vlan_dev_ioctl
;
711 dev
->destructor
= free_netdev
;
713 memset(dev
->broadcast
, 0, ETH_ALEN
);