2 * VLAN An implementation of 802.1Q VLAN tagging.
4 * Authors: Ben Greear <greearb@candelatech.com>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #ifndef _LINUX_IF_VLAN_H_
13 #define _LINUX_IF_VLAN_H_
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/bug.h>
19 #include <uapi/linux/if_vlan.h>
21 #define VLAN_HLEN 4 /* The additional bytes required by VLAN
22 * (in addition to the Ethernet header)
24 #define VLAN_ETH_HLEN 18 /* Total octets in header. */
25 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
28 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
30 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
31 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
34 * struct vlan_hdr - vlan header
35 * @h_vlan_TCI: priority and VLAN ID
36 * @h_vlan_encapsulated_proto: packet type ID or len
40 __be16 h_vlan_encapsulated_proto;
44 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
45 * @h_dest: destination ethernet address
46 * @h_source: source ethernet address
47 * @h_vlan_proto: ethernet protocol
48 * @h_vlan_TCI: priority and VLAN ID
49 * @h_vlan_encapsulated_proto: packet type ID or len
52 unsigned char h_dest[ETH_ALEN];
53 unsigned char h_source[ETH_ALEN];
56 __be16 h_vlan_encapsulated_proto;
59 #include <linux/skbuff.h>
61 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
63 return (struct vlan_ethhdr *)skb_mac_header(skb);
66 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */
67 #define VLAN_PRIO_SHIFT 13
68 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */
69 #define VLAN_TAG_PRESENT VLAN_CFI_MASK
70 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */
71 #define VLAN_N_VID 4096
73 /* found in socket.c */
74 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
76 static inline bool is_vlan_dev(const struct net_device *dev)
78 return dev->priv_flags & IFF_802_1Q_VLAN;
81 #define skb_vlan_tag_present(__skb) ((__skb)->vlan_tci & VLAN_TAG_PRESENT)
82 #define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
83 #define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK)
84 #define skb_vlan_tag_get_prio(__skb) ((__skb)->vlan_tci & VLAN_PRIO_MASK)
87 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats
88 * @rx_packets: number of received packets
89 * @rx_bytes: number of received bytes
90 * @rx_multicast: number of received multicast packets
91 * @tx_packets: number of transmitted packets
92 * @tx_bytes: number of transmitted bytes
93 * @syncp: synchronization point for 64bit counters
94 * @rx_errors: number of rx errors
95 * @tx_dropped: number of tx drops
97 struct vlan_pcpu_stats {
103 struct u64_stats_sync syncp;
108 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
110 extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
111 __be16 vlan_proto, u16 vlan_id);
112 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
113 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
114 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
117 * struct vlan_priority_tci_mapping - vlan egress priority mappings
118 * @priority: skb priority
119 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
120 * @next: pointer to next struct
122 struct vlan_priority_tci_mapping {
125 struct vlan_priority_tci_mapping *next;
128 struct proc_dir_entry;
132 * struct vlan_dev_priv - VLAN private device data
133 * @nr_ingress_mappings: number of ingress priority mappings
134 * @ingress_priority_map: ingress priority mappings
135 * @nr_egress_mappings: number of egress priority mappings
136 * @egress_priority_map: hash of egress priority mappings
137 * @vlan_proto: VLAN encapsulation protocol
138 * @vlan_id: VLAN identifier
139 * @flags: device flags
140 * @real_dev: underlying netdevice
141 * @real_dev_addr: address of underlying netdevice
142 * @dent: proc dir entry
143 * @vlan_pcpu_stats: ptr to percpu rx stats
145 struct vlan_dev_priv {
146 unsigned int nr_ingress_mappings;
147 u32 ingress_priority_map[8];
148 unsigned int nr_egress_mappings;
149 struct vlan_priority_tci_mapping *egress_priority_map[16];
155 struct net_device *real_dev;
156 unsigned char real_dev_addr[ETH_ALEN];
158 struct proc_dir_entry *dent;
159 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats;
160 #ifdef CONFIG_NET_POLL_CONTROLLER
161 struct netpoll *netpoll;
163 unsigned int nest_level;
166 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
168 return netdev_priv(dev);
172 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
174 struct vlan_priority_tci_mapping *mp;
176 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
178 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
180 if (mp->priority == skprio) {
181 return mp->vlan_qos; /* This should already be shifted
182 * to mask correctly with the
190 extern bool vlan_do_receive(struct sk_buff **skb);
192 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
193 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
195 extern int vlan_vids_add_by_dev(struct net_device *dev,
196 const struct net_device *by_dev);
197 extern void vlan_vids_del_by_dev(struct net_device *dev,
198 const struct net_device *by_dev);
200 extern bool vlan_uses_dev(const struct net_device *dev);
202 static inline int vlan_get_encap_level(struct net_device *dev)
204 BUG_ON(!is_vlan_dev(dev));
205 return vlan_dev_priv(dev)->nest_level;
208 static inline struct net_device *
209 __vlan_find_dev_deep_rcu(struct net_device *real_dev,
210 __be16 vlan_proto, u16 vlan_id)
215 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
221 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
227 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
233 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
239 static inline bool vlan_do_receive(struct sk_buff **skb)
244 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
249 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
253 static inline int vlan_vids_add_by_dev(struct net_device *dev,
254 const struct net_device *by_dev)
259 static inline void vlan_vids_del_by_dev(struct net_device *dev,
260 const struct net_device *by_dev)
264 static inline bool vlan_uses_dev(const struct net_device *dev)
268 static inline int vlan_get_encap_level(struct net_device *dev)
276 * eth_type_vlan - check for valid vlan ether type.
277 * @ethertype: ether type to check
279 * Returns true if the ether type is a vlan ether type.
281 static inline bool eth_type_vlan(__be16 ethertype)
284 case htons(ETH_P_8021Q):
285 case htons(ETH_P_8021AD):
292 static inline bool vlan_hw_offload_capable(netdev_features_t features,
295 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
297 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
303 * __vlan_insert_tag - regular VLAN tag inserting
304 * @skb: skbuff to tag
305 * @vlan_proto: VLAN encapsulation protocol
306 * @vlan_tci: VLAN TCI to insert
308 * Inserts the VLAN tag into @skb as part of the payload
309 * Returns error if skb_cow_head failes.
311 * Does not change skb->protocol so this function can be used during receive.
313 static inline int __vlan_insert_tag(struct sk_buff *skb,
314 __be16 vlan_proto, u16 vlan_tci)
316 struct vlan_ethhdr *veth;
318 if (skb_cow_head(skb, VLAN_HLEN) < 0)
321 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
323 /* Move the mac addresses to the beginning of the new header. */
324 memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN);
325 skb->mac_header -= VLAN_HLEN;
327 /* first, the ethernet type */
328 veth->h_vlan_proto = vlan_proto;
331 veth->h_vlan_TCI = htons(vlan_tci);
337 * vlan_insert_tag - regular VLAN tag inserting
338 * @skb: skbuff to tag
339 * @vlan_proto: VLAN encapsulation protocol
340 * @vlan_tci: VLAN TCI to insert
342 * Inserts the VLAN tag into @skb as part of the payload
343 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
345 * Following the skb_unshare() example, in case of error, the calling function
346 * doesn't have to worry about freeing the original skb.
348 * Does not change skb->protocol so this function can be used during receive.
350 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
351 __be16 vlan_proto, u16 vlan_tci)
355 err = __vlan_insert_tag(skb, vlan_proto, vlan_tci);
357 dev_kfree_skb_any(skb);
364 * vlan_insert_tag_set_proto - regular VLAN tag inserting
365 * @skb: skbuff to tag
366 * @vlan_proto: VLAN encapsulation protocol
367 * @vlan_tci: VLAN TCI to insert
369 * Inserts the VLAN tag into @skb as part of the payload
370 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
372 * Following the skb_unshare() example, in case of error, the calling function
373 * doesn't have to worry about freeing the original skb.
375 static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
379 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
381 skb->protocol = vlan_proto;
386 * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
387 * @skb: skbuff to tag
389 * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
391 * Following the skb_unshare() example, in case of error, the calling function
392 * doesn't have to worry about freeing the original skb.
394 static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
396 skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
397 skb_vlan_tag_get(skb));
403 * vlan_hwaccel_push_inside - pushes vlan tag to the payload
404 * @skb: skbuff to tag
406 * Checks is tag is present in @skb->vlan_tci and if it is, it pushes the
407 * VLAN tag from @skb->vlan_tci inside to the payload.
409 * Following the skb_unshare() example, in case of error, the calling function
410 * doesn't have to worry about freeing the original skb.
412 static inline struct sk_buff *vlan_hwaccel_push_inside(struct sk_buff *skb)
414 if (skb_vlan_tag_present(skb))
415 skb = __vlan_hwaccel_push_inside(skb);
420 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
421 * @skb: skbuff to tag
422 * @vlan_proto: VLAN encapsulation protocol
423 * @vlan_tci: VLAN TCI to insert
425 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
427 static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
428 __be16 vlan_proto, u16 vlan_tci)
430 skb->vlan_proto = vlan_proto;
431 skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
435 * __vlan_get_tag - get the VLAN ID that is part of the payload
436 * @skb: skbuff to query
437 * @vlan_tci: buffer to store value
439 * Returns error if the skb is not of VLAN type
441 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
443 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
445 if (!eth_type_vlan(veth->h_vlan_proto))
448 *vlan_tci = ntohs(veth->h_vlan_TCI);
453 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
454 * @skb: skbuff to query
455 * @vlan_tci: buffer to store value
457 * Returns error if @skb->vlan_tci is not set correctly
459 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
462 if (skb_vlan_tag_present(skb)) {
463 *vlan_tci = skb_vlan_tag_get(skb);
471 #define HAVE_VLAN_GET_TAG
474 * vlan_get_tag - get the VLAN ID from the skb
475 * @skb: skbuff to query
476 * @vlan_tci: buffer to store value
478 * Returns error if the skb is not VLAN tagged
480 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
482 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
483 return __vlan_hwaccel_get_tag(skb, vlan_tci);
485 return __vlan_get_tag(skb, vlan_tci);
490 * vlan_get_protocol - get protocol EtherType.
491 * @skb: skbuff to query
492 * @type: first vlan protocol
493 * @depth: buffer to store length of eth and vlan tags in bytes
495 * Returns the EtherType of the packet, regardless of whether it is
496 * vlan encapsulated (normal or hardware accelerated) or not.
498 static inline __be16 __vlan_get_protocol(struct sk_buff *skb, __be16 type,
501 unsigned int vlan_depth = skb->mac_len;
503 /* if type is 802.1Q/AD then the header should already be
504 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
507 if (eth_type_vlan(type)) {
509 if (WARN_ON(vlan_depth < VLAN_HLEN))
511 vlan_depth -= VLAN_HLEN;
513 vlan_depth = ETH_HLEN;
518 if (unlikely(!pskb_may_pull(skb,
519 vlan_depth + VLAN_HLEN)))
522 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
523 type = vh->h_vlan_encapsulated_proto;
524 vlan_depth += VLAN_HLEN;
525 } while (eth_type_vlan(type));
535 * vlan_get_protocol - get protocol EtherType.
536 * @skb: skbuff to query
538 * Returns the EtherType of the packet, regardless of whether it is
539 * vlan encapsulated (normal or hardware accelerated) or not.
541 static inline __be16 vlan_get_protocol(struct sk_buff *skb)
543 return __vlan_get_protocol(skb, skb->protocol, NULL);
546 static inline void vlan_set_encap_proto(struct sk_buff *skb,
547 struct vlan_hdr *vhdr)
550 unsigned short *rawp;
553 * Was a VLAN packet, grab the encapsulated protocol, which the layer
554 * three protocols care about.
557 proto = vhdr->h_vlan_encapsulated_proto;
558 if (eth_proto_is_802_3(proto)) {
559 skb->protocol = proto;
563 rawp = (unsigned short *)(vhdr + 1);
566 * This is a magic hack to spot IPX packets. Older Novell
567 * breaks the protocol design and runs IPX over 802.3 without
568 * an 802.2 LLC layer. We look for FFFF which isn't a used
569 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
570 * but does for the rest.
572 skb->protocol = htons(ETH_P_802_3);
577 skb->protocol = htons(ETH_P_802_2);
581 * skb_vlan_tagged - check if skb is vlan tagged.
582 * @skb: skbuff to query
584 * Returns true if the skb is tagged, regardless of whether it is hardware
585 * accelerated or not.
587 static inline bool skb_vlan_tagged(const struct sk_buff *skb)
589 if (!skb_vlan_tag_present(skb) &&
590 likely(!eth_type_vlan(skb->protocol)))
597 * skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers.
598 * @skb: skbuff to query
600 * Returns true if the skb is tagged with multiple vlan headers, regardless
601 * of whether it is hardware accelerated or not.
603 static inline bool skb_vlan_tagged_multi(const struct sk_buff *skb)
605 __be16 protocol = skb->protocol;
607 if (!skb_vlan_tag_present(skb)) {
608 struct vlan_ethhdr *veh;
610 if (likely(!eth_type_vlan(protocol)))
613 veh = (struct vlan_ethhdr *)skb->data;
614 protocol = veh->h_vlan_encapsulated_proto;
617 if (!eth_type_vlan(protocol))
624 * vlan_features_check - drop unsafe features for skb with multiple tags.
625 * @skb: skbuff to query
626 * @features: features to be checked
628 * Returns features without unsafe ones if the skb has multiple tags.
630 static inline netdev_features_t vlan_features_check(const struct sk_buff *skb,
631 netdev_features_t features)
633 if (skb_vlan_tagged_multi(skb))
634 features = netdev_intersect_features(features,
639 NETIF_F_HW_VLAN_CTAG_TX |
640 NETIF_F_HW_VLAN_STAG_TX);
646 * compare_vlan_header - Compare two vlan headers
647 * @h1: Pointer to vlan header
648 * @h2: Pointer to vlan header
650 * Compare two vlan headers, returns 0 if equal.
652 * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
654 static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
655 const struct vlan_hdr *h2)
657 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
658 return *(u32 *)h1 ^ *(u32 *)h2;
660 return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
661 ((__force u32)h1->h_vlan_encapsulated_proto ^
662 (__force u32)h2->h_vlan_encapsulated_proto);
665 #endif /* !(_LINUX_IF_VLAN_H_) */