1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * VLAN An implementation of 802.1Q VLAN tagging.
4 *
5 * Authors: Ben Greear <greearb@candelatech.com>
6 */
7 #ifndef _LINUX_IF_VLAN_H_
8 #define _LINUX_IF_VLAN_H_
9
10 #include <linux/netdevice.h>
11 #include <linux/etherdevice.h>
12 #include <linux/rtnetlink.h>
13 #include <linux/bug.h>
14 #include <uapi/linux/if_vlan.h>
15
16 #define VLAN_HLEN 4 /* The additional bytes required by VLAN
17 * (in addition to the Ethernet header)
18 */
19 #define VLAN_ETH_HLEN 18 /* Total octets in header. */
20 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
21
22 /*
23 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
24 */
25 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
26 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
27
28 /*
29 * struct vlan_hdr - vlan header
30 * @h_vlan_TCI: priority and VLAN ID
31 * @h_vlan_encapsulated_proto: packet type ID or len
32 */
33 struct vlan_hdr {
34 __be16 h_vlan_TCI;
35 __be16 h_vlan_encapsulated_proto;
36 };
37
38 /**
39 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
40 * @h_dest: destination ethernet address
41 * @h_source: source ethernet address
42 * @h_vlan_proto: ethernet protocol
43 * @h_vlan_TCI: priority and VLAN ID
44 * @h_vlan_encapsulated_proto: packet type ID or len
45 */
46 struct vlan_ethhdr {
47 unsigned char h_dest[ETH_ALEN];
48 unsigned char h_source[ETH_ALEN];
49 __be16 h_vlan_proto;
50 __be16 h_vlan_TCI;
51 __be16 h_vlan_encapsulated_proto;
52 };
53
54 #include <linux/skbuff.h>
55
vlan_eth_hdr(const struct sk_buff * skb)56 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
57 {
58 return (struct vlan_ethhdr *)skb_mac_header(skb);
59 }
60
61 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */
62 #define VLAN_PRIO_SHIFT 13
63 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator / Drop Eligible Indicator */
64 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */
65 #define VLAN_N_VID 4096
66
67 /* found in socket.c */
68 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
69
is_vlan_dev(const struct net_device * dev)70 static inline bool is_vlan_dev(const struct net_device *dev)
71 {
72 return dev->priv_flags & IFF_802_1Q_VLAN;
73 }
74
75 #define skb_vlan_tag_present(__skb) ((__skb)->vlan_present)
76 #define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci)
77 #define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK)
78 #define skb_vlan_tag_get_cfi(__skb) (!!((__skb)->vlan_tci & VLAN_CFI_MASK))
79 #define skb_vlan_tag_get_prio(__skb) (((__skb)->vlan_tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT)
80
vlan_get_rx_ctag_filter_info(struct net_device * dev)81 static inline int vlan_get_rx_ctag_filter_info(struct net_device *dev)
82 {
83 ASSERT_RTNL();
84 return notifier_to_errno(call_netdevice_notifiers(NETDEV_CVLAN_FILTER_PUSH_INFO, dev));
85 }
86
vlan_drop_rx_ctag_filter_info(struct net_device * dev)87 static inline void vlan_drop_rx_ctag_filter_info(struct net_device *dev)
88 {
89 ASSERT_RTNL();
90 call_netdevice_notifiers(NETDEV_CVLAN_FILTER_DROP_INFO, dev);
91 }
92
vlan_get_rx_stag_filter_info(struct net_device * dev)93 static inline int vlan_get_rx_stag_filter_info(struct net_device *dev)
94 {
95 ASSERT_RTNL();
96 return notifier_to_errno(call_netdevice_notifiers(NETDEV_SVLAN_FILTER_PUSH_INFO, dev));
97 }
98
vlan_drop_rx_stag_filter_info(struct net_device * dev)99 static inline void vlan_drop_rx_stag_filter_info(struct net_device *dev)
100 {
101 ASSERT_RTNL();
102 call_netdevice_notifiers(NETDEV_SVLAN_FILTER_DROP_INFO, dev);
103 }
104
105 /**
106 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats
107 * @rx_packets: number of received packets
108 * @rx_bytes: number of received bytes
109 * @rx_multicast: number of received multicast packets
110 * @tx_packets: number of transmitted packets
111 * @tx_bytes: number of transmitted bytes
112 * @syncp: synchronization point for 64bit counters
113 * @rx_errors: number of rx errors
114 * @tx_dropped: number of tx drops
115 */
116 struct vlan_pcpu_stats {
117 u64 rx_packets;
118 u64 rx_bytes;
119 u64 rx_multicast;
120 u64 tx_packets;
121 u64 tx_bytes;
122 struct u64_stats_sync syncp;
123 u32 rx_errors;
124 u32 tx_dropped;
125 };
126
127 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
128
129 extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
130 __be16 vlan_proto, u16 vlan_id);
131 extern int vlan_for_each(struct net_device *dev,
132 int (*action)(struct net_device *dev, int vid,
133 void *arg), void *arg);
134 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
135 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
136 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
137
138 /**
139 * struct vlan_priority_tci_mapping - vlan egress priority mappings
140 * @priority: skb priority
141 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
142 * @next: pointer to next struct
143 */
144 struct vlan_priority_tci_mapping {
145 u32 priority;
146 u16 vlan_qos;
147 struct vlan_priority_tci_mapping *next;
148 };
149
150 struct proc_dir_entry;
151 struct netpoll;
152
153 /**
154 * struct vlan_dev_priv - VLAN private device data
155 * @nr_ingress_mappings: number of ingress priority mappings
156 * @ingress_priority_map: ingress priority mappings
157 * @nr_egress_mappings: number of egress priority mappings
158 * @egress_priority_map: hash of egress priority mappings
159 * @vlan_proto: VLAN encapsulation protocol
160 * @vlan_id: VLAN identifier
161 * @flags: device flags
162 * @real_dev: underlying netdevice
163 * @real_dev_addr: address of underlying netdevice
164 * @dent: proc dir entry
165 * @vlan_pcpu_stats: ptr to percpu rx stats
166 */
167 struct vlan_dev_priv {
168 unsigned int nr_ingress_mappings;
169 u32 ingress_priority_map[8];
170 unsigned int nr_egress_mappings;
171 struct vlan_priority_tci_mapping *egress_priority_map[16];
172
173 __be16 vlan_proto;
174 u16 vlan_id;
175 u16 flags;
176
177 struct net_device *real_dev;
178 unsigned char real_dev_addr[ETH_ALEN];
179
180 struct proc_dir_entry *dent;
181 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats;
182 #ifdef CONFIG_NET_POLL_CONTROLLER
183 struct netpoll *netpoll;
184 #endif
185 };
186
vlan_dev_priv(const struct net_device * dev)187 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
188 {
189 return netdev_priv(dev);
190 }
191
192 static inline u16
vlan_dev_get_egress_qos_mask(struct net_device * dev,u32 skprio)193 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
194 {
195 struct vlan_priority_tci_mapping *mp;
196
197 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
198
199 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
200 while (mp) {
201 if (mp->priority == skprio) {
202 return mp->vlan_qos; /* This should already be shifted
203 * to mask correctly with the
204 * VLAN's TCI */
205 }
206 mp = mp->next;
207 }
208 return 0;
209 }
210
211 extern bool vlan_do_receive(struct sk_buff **skb);
212
213 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
214 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
215
216 extern int vlan_vids_add_by_dev(struct net_device *dev,
217 const struct net_device *by_dev);
218 extern void vlan_vids_del_by_dev(struct net_device *dev,
219 const struct net_device *by_dev);
220
221 extern bool vlan_uses_dev(const struct net_device *dev);
222
223 #else
224 static inline struct net_device *
__vlan_find_dev_deep_rcu(struct net_device * real_dev,__be16 vlan_proto,u16 vlan_id)225 __vlan_find_dev_deep_rcu(struct net_device *real_dev,
226 __be16 vlan_proto, u16 vlan_id)
227 {
228 return NULL;
229 }
230
231 static inline int
vlan_for_each(struct net_device * dev,int (* action)(struct net_device * dev,int vid,void * arg),void * arg)232 vlan_for_each(struct net_device *dev,
233 int (*action)(struct net_device *dev, int vid, void *arg),
234 void *arg)
235 {
236 return 0;
237 }
238
vlan_dev_real_dev(const struct net_device * dev)239 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
240 {
241 BUG();
242 return NULL;
243 }
244
vlan_dev_vlan_id(const struct net_device * dev)245 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
246 {
247 BUG();
248 return 0;
249 }
250
vlan_dev_vlan_proto(const struct net_device * dev)251 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
252 {
253 BUG();
254 return 0;
255 }
256
vlan_dev_get_egress_qos_mask(struct net_device * dev,u32 skprio)257 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
258 u32 skprio)
259 {
260 return 0;
261 }
262
vlan_do_receive(struct sk_buff ** skb)263 static inline bool vlan_do_receive(struct sk_buff **skb)
264 {
265 return false;
266 }
267
vlan_vid_add(struct net_device * dev,__be16 proto,u16 vid)268 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
269 {
270 return 0;
271 }
272
vlan_vid_del(struct net_device * dev,__be16 proto,u16 vid)273 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
274 {
275 }
276
vlan_vids_add_by_dev(struct net_device * dev,const struct net_device * by_dev)277 static inline int vlan_vids_add_by_dev(struct net_device *dev,
278 const struct net_device *by_dev)
279 {
280 return 0;
281 }
282
vlan_vids_del_by_dev(struct net_device * dev,const struct net_device * by_dev)283 static inline void vlan_vids_del_by_dev(struct net_device *dev,
284 const struct net_device *by_dev)
285 {
286 }
287
vlan_uses_dev(const struct net_device * dev)288 static inline bool vlan_uses_dev(const struct net_device *dev)
289 {
290 return false;
291 }
292 #endif
293
294 /**
295 * eth_type_vlan - check for valid vlan ether type.
296 * @ethertype: ether type to check
297 *
298 * Returns true if the ether type is a vlan ether type.
299 */
eth_type_vlan(__be16 ethertype)300 static inline bool eth_type_vlan(__be16 ethertype)
301 {
302 switch (ethertype) {
303 case htons(ETH_P_8021Q):
304 case htons(ETH_P_8021AD):
305 return true;
306 default:
307 return false;
308 }
309 }
310
vlan_hw_offload_capable(netdev_features_t features,__be16 proto)311 static inline bool vlan_hw_offload_capable(netdev_features_t features,
312 __be16 proto)
313 {
314 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
315 return true;
316 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
317 return true;
318 return false;
319 }
320
321 /**
322 * __vlan_insert_inner_tag - inner VLAN tag inserting
323 * @skb: skbuff to tag
324 * @vlan_proto: VLAN encapsulation protocol
325 * @vlan_tci: VLAN TCI to insert
326 * @mac_len: MAC header length including outer vlan headers
327 *
328 * Inserts the VLAN tag into @skb as part of the payload at offset mac_len
329 * Returns error if skb_cow_head fails.
330 *
331 * Does not change skb->protocol so this function can be used during receive.
332 */
__vlan_insert_inner_tag(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci,unsigned int mac_len)333 static inline int __vlan_insert_inner_tag(struct sk_buff *skb,
334 __be16 vlan_proto, u16 vlan_tci,
335 unsigned int mac_len)
336 {
337 struct vlan_ethhdr *veth;
338
339 if (skb_cow_head(skb, VLAN_HLEN) < 0)
340 return -ENOMEM;
341
342 skb_push(skb, VLAN_HLEN);
343
344 /* Move the mac header sans proto to the beginning of the new header. */
345 if (likely(mac_len > ETH_TLEN))
346 memmove(skb->data, skb->data + VLAN_HLEN, mac_len - ETH_TLEN);
347 skb->mac_header -= VLAN_HLEN;
348
349 veth = (struct vlan_ethhdr *)(skb->data + mac_len - ETH_HLEN);
350
351 /* first, the ethernet type */
352 if (likely(mac_len >= ETH_TLEN)) {
353 /* h_vlan_encapsulated_proto should already be populated, and
354 * skb->data has space for h_vlan_proto
355 */
356 veth->h_vlan_proto = vlan_proto;
357 } else {
358 /* h_vlan_encapsulated_proto should not be populated, and
359 * skb->data has no space for h_vlan_proto
360 */
361 veth->h_vlan_encapsulated_proto = skb->protocol;
362 }
363
364 /* now, the TCI */
365 veth->h_vlan_TCI = htons(vlan_tci);
366
367 return 0;
368 }
369
370 /**
371 * __vlan_insert_tag - regular VLAN tag inserting
372 * @skb: skbuff to tag
373 * @vlan_proto: VLAN encapsulation protocol
374 * @vlan_tci: VLAN TCI to insert
375 *
376 * Inserts the VLAN tag into @skb as part of the payload
377 * Returns error if skb_cow_head fails.
378 *
379 * Does not change skb->protocol so this function can be used during receive.
380 */
__vlan_insert_tag(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci)381 static inline int __vlan_insert_tag(struct sk_buff *skb,
382 __be16 vlan_proto, u16 vlan_tci)
383 {
384 return __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
385 }
386
387 /**
388 * vlan_insert_inner_tag - inner VLAN tag inserting
389 * @skb: skbuff to tag
390 * @vlan_proto: VLAN encapsulation protocol
391 * @vlan_tci: VLAN TCI to insert
392 * @mac_len: MAC header length including outer vlan headers
393 *
394 * Inserts the VLAN tag into @skb as part of the payload at offset mac_len
395 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
396 *
397 * Following the skb_unshare() example, in case of error, the calling function
398 * doesn't have to worry about freeing the original skb.
399 *
400 * Does not change skb->protocol so this function can be used during receive.
401 */
vlan_insert_inner_tag(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci,unsigned int mac_len)402 static inline struct sk_buff *vlan_insert_inner_tag(struct sk_buff *skb,
403 __be16 vlan_proto,
404 u16 vlan_tci,
405 unsigned int mac_len)
406 {
407 int err;
408
409 err = __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, mac_len);
410 if (err) {
411 dev_kfree_skb_any(skb);
412 return NULL;
413 }
414 return skb;
415 }
416
417 /**
418 * vlan_insert_tag - regular VLAN tag inserting
419 * @skb: skbuff to tag
420 * @vlan_proto: VLAN encapsulation protocol
421 * @vlan_tci: VLAN TCI to insert
422 *
423 * Inserts the VLAN tag into @skb as part of the payload
424 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
425 *
426 * Following the skb_unshare() example, in case of error, the calling function
427 * doesn't have to worry about freeing the original skb.
428 *
429 * Does not change skb->protocol so this function can be used during receive.
430 */
vlan_insert_tag(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci)431 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
432 __be16 vlan_proto, u16 vlan_tci)
433 {
434 return vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
435 }
436
437 /**
438 * vlan_insert_tag_set_proto - regular VLAN tag inserting
439 * @skb: skbuff to tag
440 * @vlan_proto: VLAN encapsulation protocol
441 * @vlan_tci: VLAN TCI to insert
442 *
443 * Inserts the VLAN tag into @skb as part of the payload
444 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
445 *
446 * Following the skb_unshare() example, in case of error, the calling function
447 * doesn't have to worry about freeing the original skb.
448 */
vlan_insert_tag_set_proto(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci)449 static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
450 __be16 vlan_proto,
451 u16 vlan_tci)
452 {
453 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
454 if (skb)
455 skb->protocol = vlan_proto;
456 return skb;
457 }
458
459 /**
460 * __vlan_hwaccel_clear_tag - clear hardware accelerated VLAN info
461 * @skb: skbuff to clear
462 *
463 * Clears the VLAN information from @skb
464 */
__vlan_hwaccel_clear_tag(struct sk_buff * skb)465 static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb)
466 {
467 skb->vlan_present = 0;
468 }
469
470 /**
471 * __vlan_hwaccel_copy_tag - copy hardware accelerated VLAN info from another skb
472 * @dst: skbuff to copy to
473 * @src: skbuff to copy from
474 *
475 * Copies VLAN information from @src to @dst (for branchless code)
476 */
__vlan_hwaccel_copy_tag(struct sk_buff * dst,const struct sk_buff * src)477 static inline void __vlan_hwaccel_copy_tag(struct sk_buff *dst, const struct sk_buff *src)
478 {
479 dst->vlan_present = src->vlan_present;
480 dst->vlan_proto = src->vlan_proto;
481 dst->vlan_tci = src->vlan_tci;
482 }
483
484 /*
485 * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
486 * @skb: skbuff to tag
487 *
488 * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
489 *
490 * Following the skb_unshare() example, in case of error, the calling function
491 * doesn't have to worry about freeing the original skb.
492 */
__vlan_hwaccel_push_inside(struct sk_buff * skb)493 static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
494 {
495 skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
496 skb_vlan_tag_get(skb));
497 if (likely(skb))
498 __vlan_hwaccel_clear_tag(skb);
499 return skb;
500 }
501
502 /**
503 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
504 * @skb: skbuff to tag
505 * @vlan_proto: VLAN encapsulation protocol
506 * @vlan_tci: VLAN TCI to insert
507 *
508 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
509 */
__vlan_hwaccel_put_tag(struct sk_buff * skb,__be16 vlan_proto,u16 vlan_tci)510 static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
511 __be16 vlan_proto, u16 vlan_tci)
512 {
513 skb->vlan_proto = vlan_proto;
514 skb->vlan_tci = vlan_tci;
515 skb->vlan_present = 1;
516 }
517
518 /**
519 * __vlan_get_tag - get the VLAN ID that is part of the payload
520 * @skb: skbuff to query
521 * @vlan_tci: buffer to store value
522 *
523 * Returns error if the skb is not of VLAN type
524 */
__vlan_get_tag(const struct sk_buff * skb,u16 * vlan_tci)525 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
526 {
527 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
528
529 if (!eth_type_vlan(veth->h_vlan_proto))
530 return -EINVAL;
531
532 *vlan_tci = ntohs(veth->h_vlan_TCI);
533 return 0;
534 }
535
536 /**
537 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
538 * @skb: skbuff to query
539 * @vlan_tci: buffer to store value
540 *
541 * Returns error if @skb->vlan_tci is not set correctly
542 */
__vlan_hwaccel_get_tag(const struct sk_buff * skb,u16 * vlan_tci)543 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
544 u16 *vlan_tci)
545 {
546 if (skb_vlan_tag_present(skb)) {
547 *vlan_tci = skb_vlan_tag_get(skb);
548 return 0;
549 } else {
550 *vlan_tci = 0;
551 return -EINVAL;
552 }
553 }
554
555 /**
556 * vlan_get_tag - get the VLAN ID from the skb
557 * @skb: skbuff to query
558 * @vlan_tci: buffer to store value
559 *
560 * Returns error if the skb is not VLAN tagged
561 */
vlan_get_tag(const struct sk_buff * skb,u16 * vlan_tci)562 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
563 {
564 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
565 return __vlan_hwaccel_get_tag(skb, vlan_tci);
566 } else {
567 return __vlan_get_tag(skb, vlan_tci);
568 }
569 }
570
571 /**
572 * vlan_get_protocol - get protocol EtherType.
573 * @skb: skbuff to query
574 * @type: first vlan protocol
575 * @depth: buffer to store length of eth and vlan tags in bytes
576 *
577 * Returns the EtherType of the packet, regardless of whether it is
578 * vlan encapsulated (normal or hardware accelerated) or not.
579 */
__vlan_get_protocol(struct sk_buff * skb,__be16 type,int * depth)580 static inline __be16 __vlan_get_protocol(struct sk_buff *skb, __be16 type,
581 int *depth)
582 {
583 unsigned int vlan_depth = skb->mac_len;
584
585 /* if type is 802.1Q/AD then the header should already be
586 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
587 * ETH_HLEN otherwise
588 */
589 if (eth_type_vlan(type)) {
590 if (vlan_depth) {
591 if (WARN_ON(vlan_depth < VLAN_HLEN))
592 return 0;
593 vlan_depth -= VLAN_HLEN;
594 } else {
595 vlan_depth = ETH_HLEN;
596 }
597 do {
598 struct vlan_hdr *vh;
599
600 if (unlikely(!pskb_may_pull(skb,
601 vlan_depth + VLAN_HLEN)))
602 return 0;
603
604 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
605 type = vh->h_vlan_encapsulated_proto;
606 vlan_depth += VLAN_HLEN;
607 } while (eth_type_vlan(type));
608 }
609
610 if (depth)
611 *depth = vlan_depth;
612
613 return type;
614 }
615
616 /**
617 * vlan_get_protocol - get protocol EtherType.
618 * @skb: skbuff to query
619 *
620 * Returns the EtherType of the packet, regardless of whether it is
621 * vlan encapsulated (normal or hardware accelerated) or not.
622 */
vlan_get_protocol(struct sk_buff * skb)623 static inline __be16 vlan_get_protocol(struct sk_buff *skb)
624 {
625 return __vlan_get_protocol(skb, skb->protocol, NULL);
626 }
627
vlan_set_encap_proto(struct sk_buff * skb,struct vlan_hdr * vhdr)628 static inline void vlan_set_encap_proto(struct sk_buff *skb,
629 struct vlan_hdr *vhdr)
630 {
631 __be16 proto;
632 unsigned short *rawp;
633
634 /*
635 * Was a VLAN packet, grab the encapsulated protocol, which the layer
636 * three protocols care about.
637 */
638
639 proto = vhdr->h_vlan_encapsulated_proto;
640 if (eth_proto_is_802_3(proto)) {
641 skb->protocol = proto;
642 return;
643 }
644
645 rawp = (unsigned short *)(vhdr + 1);
646 if (*rawp == 0xFFFF)
647 /*
648 * This is a magic hack to spot IPX packets. Older Novell
649 * breaks the protocol design and runs IPX over 802.3 without
650 * an 802.2 LLC layer. We look for FFFF which isn't a used
651 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
652 * but does for the rest.
653 */
654 skb->protocol = htons(ETH_P_802_3);
655 else
656 /*
657 * Real 802.2 LLC
658 */
659 skb->protocol = htons(ETH_P_802_2);
660 }
661
662 /**
663 * skb_vlan_tagged - check if skb is vlan tagged.
664 * @skb: skbuff to query
665 *
666 * Returns true if the skb is tagged, regardless of whether it is hardware
667 * accelerated or not.
668 */
skb_vlan_tagged(const struct sk_buff * skb)669 static inline bool skb_vlan_tagged(const struct sk_buff *skb)
670 {
671 if (!skb_vlan_tag_present(skb) &&
672 likely(!eth_type_vlan(skb->protocol)))
673 return false;
674
675 return true;
676 }
677
678 /**
679 * skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers.
680 * @skb: skbuff to query
681 *
682 * Returns true if the skb is tagged with multiple vlan headers, regardless
683 * of whether it is hardware accelerated or not.
684 */
skb_vlan_tagged_multi(struct sk_buff * skb)685 static inline bool skb_vlan_tagged_multi(struct sk_buff *skb)
686 {
687 __be16 protocol = skb->protocol;
688
689 if (!skb_vlan_tag_present(skb)) {
690 struct vlan_ethhdr *veh;
691
692 if (likely(!eth_type_vlan(protocol)))
693 return false;
694
695 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
696 return false;
697
698 veh = (struct vlan_ethhdr *)skb->data;
699 protocol = veh->h_vlan_encapsulated_proto;
700 }
701
702 if (!eth_type_vlan(protocol))
703 return false;
704
705 return true;
706 }
707
708 /**
709 * vlan_features_check - drop unsafe features for skb with multiple tags.
710 * @skb: skbuff to query
711 * @features: features to be checked
712 *
713 * Returns features without unsafe ones if the skb has multiple tags.
714 */
vlan_features_check(struct sk_buff * skb,netdev_features_t features)715 static inline netdev_features_t vlan_features_check(struct sk_buff *skb,
716 netdev_features_t features)
717 {
718 if (skb_vlan_tagged_multi(skb)) {
719 /* In the case of multi-tagged packets, use a direct mask
720 * instead of using netdev_interesect_features(), to make
721 * sure that only devices supporting NETIF_F_HW_CSUM will
722 * have checksum offloading support.
723 */
724 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
725 NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX |
726 NETIF_F_HW_VLAN_STAG_TX;
727 }
728
729 return features;
730 }
731
732 /**
733 * compare_vlan_header - Compare two vlan headers
734 * @h1: Pointer to vlan header
735 * @h2: Pointer to vlan header
736 *
737 * Compare two vlan headers, returns 0 if equal.
738 *
739 * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
740 */
compare_vlan_header(const struct vlan_hdr * h1,const struct vlan_hdr * h2)741 static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
742 const struct vlan_hdr *h2)
743 {
744 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
745 return *(u32 *)h1 ^ *(u32 *)h2;
746 #else
747 return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
748 ((__force u32)h1->h_vlan_encapsulated_proto ^
749 (__force u32)h2->h_vlan_encapsulated_proto);
750 #endif
751 }
752 #endif /* !(_LINUX_IF_VLAN_H_) */
753