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 */
33 #define VLAN_MAX_DEPTH 8 /* Max. number of nested VLAN tags parsed */
36 * struct vlan_hdr - vlan header
37 * @h_vlan_TCI: priority and VLAN ID
38 * @h_vlan_encapsulated_proto: packet type ID or len
42 __be16 h_vlan_encapsulated_proto;
46 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
47 * @h_dest: destination ethernet address
48 * @h_source: source ethernet address
49 * @h_vlan_proto: ethernet protocol
50 * @h_vlan_TCI: priority and VLAN ID
51 * @h_vlan_encapsulated_proto: packet type ID or len
54 unsigned char h_dest[ETH_ALEN];
55 unsigned char h_source[ETH_ALEN];
58 __be16 h_vlan_encapsulated_proto;
61 #include <linux/skbuff.h>
63 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
65 return (struct vlan_ethhdr *)skb_mac_header(skb);
68 #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */
69 #define VLAN_PRIO_SHIFT 13
70 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */
71 #define VLAN_TAG_PRESENT VLAN_CFI_MASK
72 #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */
73 #define VLAN_N_VID 4096
75 /* found in socket.c */
76 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
78 static inline bool is_vlan_dev(const struct net_device *dev)
80 return dev->priv_flags & IFF_802_1Q_VLAN;
83 #define skb_vlan_tag_present(__skb) ((__skb)->vlan_tci & VLAN_TAG_PRESENT)
84 #define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
85 #define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK)
86 #define skb_vlan_tag_get_prio(__skb) ((__skb)->vlan_tci & VLAN_PRIO_MASK)
89 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats
90 * @rx_packets: number of received packets
91 * @rx_bytes: number of received bytes
92 * @rx_multicast: number of received multicast packets
93 * @tx_packets: number of transmitted packets
94 * @tx_bytes: number of transmitted bytes
95 * @syncp: synchronization point for 64bit counters
96 * @rx_errors: number of rx errors
97 * @tx_dropped: number of tx drops
99 struct vlan_pcpu_stats {
105 struct u64_stats_sync syncp;
110 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
112 extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
113 __be16 vlan_proto, u16 vlan_id);
114 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
115 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
116 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
119 * struct vlan_priority_tci_mapping - vlan egress priority mappings
120 * @priority: skb priority
121 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
122 * @next: pointer to next struct
124 struct vlan_priority_tci_mapping {
127 struct vlan_priority_tci_mapping *next;
130 struct proc_dir_entry;
134 * struct vlan_dev_priv - VLAN private device data
135 * @nr_ingress_mappings: number of ingress priority mappings
136 * @ingress_priority_map: ingress priority mappings
137 * @nr_egress_mappings: number of egress priority mappings
138 * @egress_priority_map: hash of egress priority mappings
139 * @vlan_proto: VLAN encapsulation protocol
140 * @vlan_id: VLAN identifier
141 * @flags: device flags
142 * @real_dev: underlying netdevice
143 * @real_dev_addr: address of underlying netdevice
144 * @dent: proc dir entry
145 * @vlan_pcpu_stats: ptr to percpu rx stats
147 struct vlan_dev_priv {
148 unsigned int nr_ingress_mappings;
149 u32 ingress_priority_map[8];
150 unsigned int nr_egress_mappings;
151 struct vlan_priority_tci_mapping *egress_priority_map[16];
157 struct net_device *real_dev;
158 unsigned char real_dev_addr[ETH_ALEN];
160 struct proc_dir_entry *dent;
161 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats;
162 #ifdef CONFIG_NET_POLL_CONTROLLER
163 struct netpoll *netpoll;
165 unsigned int nest_level;
168 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
170 return netdev_priv(dev);
174 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
176 struct vlan_priority_tci_mapping *mp;
178 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
180 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
182 if (mp->priority == skprio) {
183 return mp->vlan_qos; /* This should already be shifted
184 * to mask correctly with the
192 extern bool vlan_do_receive(struct sk_buff **skb);
194 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
195 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
197 extern int vlan_vids_add_by_dev(struct net_device *dev,
198 const struct net_device *by_dev);
199 extern void vlan_vids_del_by_dev(struct net_device *dev,
200 const struct net_device *by_dev);
202 extern bool vlan_uses_dev(const struct net_device *dev);
204 static inline int vlan_get_encap_level(struct net_device *dev)
206 BUG_ON(!is_vlan_dev(dev));
207 return vlan_dev_priv(dev)->nest_level;
210 static inline struct net_device *
211 __vlan_find_dev_deep_rcu(struct net_device *real_dev,
212 __be16 vlan_proto, u16 vlan_id)
217 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
223 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
229 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
235 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
241 static inline bool vlan_do_receive(struct sk_buff **skb)
246 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
251 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
255 static inline int vlan_vids_add_by_dev(struct net_device *dev,
256 const struct net_device *by_dev)
261 static inline void vlan_vids_del_by_dev(struct net_device *dev,
262 const struct net_device *by_dev)
266 static inline bool vlan_uses_dev(const struct net_device *dev)
270 static inline int vlan_get_encap_level(struct net_device *dev)
278 * eth_type_vlan - check for valid vlan ether type.
279 * @ethertype: ether type to check
281 * Returns true if the ether type is a vlan ether type.
283 static inline bool eth_type_vlan(__be16 ethertype)
286 case htons(ETH_P_8021Q):
287 case htons(ETH_P_8021AD):
294 static inline bool vlan_hw_offload_capable(netdev_features_t features,
297 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
299 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
305 * __vlan_insert_tag - regular VLAN tag inserting
306 * @skb: skbuff to tag
307 * @vlan_proto: VLAN encapsulation protocol
308 * @vlan_tci: VLAN TCI to insert
310 * Inserts the VLAN tag into @skb as part of the payload
311 * Returns error if skb_cow_head failes.
313 * Does not change skb->protocol so this function can be used during receive.
315 static inline int __vlan_insert_tag(struct sk_buff *skb,
316 __be16 vlan_proto, u16 vlan_tci)
318 struct vlan_ethhdr *veth;
320 if (skb_cow_head(skb, VLAN_HLEN) < 0)
323 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
325 /* Move the mac addresses to the beginning of the new header. */
326 memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN);
327 skb->mac_header -= VLAN_HLEN;
329 /* first, the ethernet type */
330 veth->h_vlan_proto = vlan_proto;
333 veth->h_vlan_TCI = htons(vlan_tci);
339 * vlan_insert_tag - regular VLAN tag inserting
340 * @skb: skbuff to tag
341 * @vlan_proto: VLAN encapsulation protocol
342 * @vlan_tci: VLAN TCI to insert
344 * Inserts the VLAN tag into @skb as part of the payload
345 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
347 * Following the skb_unshare() example, in case of error, the calling function
348 * doesn't have to worry about freeing the original skb.
350 * Does not change skb->protocol so this function can be used during receive.
352 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
353 __be16 vlan_proto, u16 vlan_tci)
357 err = __vlan_insert_tag(skb, vlan_proto, vlan_tci);
359 dev_kfree_skb_any(skb);
366 * vlan_insert_tag_set_proto - regular VLAN tag inserting
367 * @skb: skbuff to tag
368 * @vlan_proto: VLAN encapsulation protocol
369 * @vlan_tci: VLAN TCI to insert
371 * Inserts the VLAN tag into @skb as part of the payload
372 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
374 * Following the skb_unshare() example, in case of error, the calling function
375 * doesn't have to worry about freeing the original skb.
377 static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
381 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
383 skb->protocol = vlan_proto;
388 * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
389 * @skb: skbuff to tag
391 * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
393 * Following the skb_unshare() example, in case of error, the calling function
394 * doesn't have to worry about freeing the original skb.
396 static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
398 skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
399 skb_vlan_tag_get(skb));
405 * vlan_hwaccel_push_inside - pushes vlan tag to the payload
406 * @skb: skbuff to tag
408 * Checks is tag is present in @skb->vlan_tci and if it is, it pushes the
409 * VLAN tag from @skb->vlan_tci inside to the payload.
411 * Following the skb_unshare() example, in case of error, the calling function
412 * doesn't have to worry about freeing the original skb.
414 static inline struct sk_buff *vlan_hwaccel_push_inside(struct sk_buff *skb)
416 if (skb_vlan_tag_present(skb))
417 skb = __vlan_hwaccel_push_inside(skb);
422 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
423 * @skb: skbuff to tag
424 * @vlan_proto: VLAN encapsulation protocol
425 * @vlan_tci: VLAN TCI to insert
427 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
429 static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
430 __be16 vlan_proto, u16 vlan_tci)
432 skb->vlan_proto = vlan_proto;
433 skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
437 * __vlan_get_tag - get the VLAN ID that is part of the payload
438 * @skb: skbuff to query
439 * @vlan_tci: buffer to store value
441 * Returns error if the skb is not of VLAN type
443 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
445 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
447 if (!eth_type_vlan(veth->h_vlan_proto))
450 *vlan_tci = ntohs(veth->h_vlan_TCI);
455 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
456 * @skb: skbuff to query
457 * @vlan_tci: buffer to store value
459 * Returns error if @skb->vlan_tci is not set correctly
461 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
464 if (skb_vlan_tag_present(skb)) {
465 *vlan_tci = skb_vlan_tag_get(skb);
473 #define HAVE_VLAN_GET_TAG
476 * vlan_get_tag - get the VLAN ID from the skb
477 * @skb: skbuff to query
478 * @vlan_tci: buffer to store value
480 * Returns error if the skb is not VLAN tagged
482 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
484 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
485 return __vlan_hwaccel_get_tag(skb, vlan_tci);
487 return __vlan_get_tag(skb, vlan_tci);
492 * vlan_get_protocol - get protocol EtherType.
493 * @skb: skbuff to query
494 * @type: first vlan protocol
495 * @depth: buffer to store length of eth and vlan tags in bytes
497 * Returns the EtherType of the packet, regardless of whether it is
498 * vlan encapsulated (normal or hardware accelerated) or not.
500 static inline __be16 __vlan_get_protocol(const struct sk_buff *skb, __be16 type,
503 unsigned int vlan_depth = skb->mac_len, parse_depth = VLAN_MAX_DEPTH;
505 /* if type is 802.1Q/AD then the header should already be
506 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
509 if (eth_type_vlan(type)) {
511 if (WARN_ON(vlan_depth < VLAN_HLEN))
513 vlan_depth -= VLAN_HLEN;
515 vlan_depth = ETH_HLEN;
518 struct vlan_hdr vhdr, *vh;
520 vh = skb_header_pointer(skb, vlan_depth, sizeof(vhdr), &vhdr);
521 if (unlikely(!vh || !--parse_depth))
524 type = vh->h_vlan_encapsulated_proto;
525 vlan_depth += VLAN_HLEN;
526 } while (eth_type_vlan(type));
536 * vlan_get_protocol - get protocol EtherType.
537 * @skb: skbuff to query
539 * Returns the EtherType of the packet, regardless of whether it is
540 * vlan encapsulated (normal or hardware accelerated) or not.
542 static inline __be16 vlan_get_protocol(const struct sk_buff *skb)
544 return __vlan_get_protocol(skb, skb->protocol, NULL);
547 /* A getter for the SKB protocol field which will handle VLAN tags consistently
548 * whether VLAN acceleration is enabled or not.
550 static inline __be16 skb_protocol(const struct sk_buff *skb, bool skip_vlan)
553 /* VLAN acceleration strips the VLAN header from the skb and
554 * moves it to skb->vlan_proto
556 return skb_vlan_tag_present(skb) ? skb->vlan_proto : skb->protocol;
558 return vlan_get_protocol(skb);
561 static inline void vlan_set_encap_proto(struct sk_buff *skb,
562 struct vlan_hdr *vhdr)
565 unsigned short *rawp;
568 * Was a VLAN packet, grab the encapsulated protocol, which the layer
569 * three protocols care about.
572 proto = vhdr->h_vlan_encapsulated_proto;
573 if (eth_proto_is_802_3(proto)) {
574 skb->protocol = proto;
578 rawp = (unsigned short *)(vhdr + 1);
581 * This is a magic hack to spot IPX packets. Older Novell
582 * breaks the protocol design and runs IPX over 802.3 without
583 * an 802.2 LLC layer. We look for FFFF which isn't a used
584 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
585 * but does for the rest.
587 skb->protocol = htons(ETH_P_802_3);
592 skb->protocol = htons(ETH_P_802_2);
596 * skb_vlan_tagged - check if skb is vlan tagged.
597 * @skb: skbuff to query
599 * Returns true if the skb is tagged, regardless of whether it is hardware
600 * accelerated or not.
602 static inline bool skb_vlan_tagged(const struct sk_buff *skb)
604 if (!skb_vlan_tag_present(skb) &&
605 likely(!eth_type_vlan(skb->protocol)))
612 * skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers.
613 * @skb: skbuff to query
615 * Returns true if the skb is tagged with multiple vlan headers, regardless
616 * of whether it is hardware accelerated or not.
618 static inline bool skb_vlan_tagged_multi(struct sk_buff *skb)
620 __be16 protocol = skb->protocol;
622 if (!skb_vlan_tag_present(skb)) {
623 struct vlan_ethhdr *veh;
625 if (likely(!eth_type_vlan(protocol)))
628 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
631 veh = (struct vlan_ethhdr *)skb->data;
632 protocol = veh->h_vlan_encapsulated_proto;
635 if (!eth_type_vlan(protocol))
642 * vlan_features_check - drop unsafe features for skb with multiple tags.
643 * @skb: skbuff to query
644 * @features: features to be checked
646 * Returns features without unsafe ones if the skb has multiple tags.
648 static inline netdev_features_t vlan_features_check(struct sk_buff *skb,
649 netdev_features_t features)
651 if (skb_vlan_tagged_multi(skb)) {
652 /* In the case of multi-tagged packets, use a direct mask
653 * instead of using netdev_interesect_features(), to make
654 * sure that only devices supporting NETIF_F_HW_CSUM will
655 * have checksum offloading support.
657 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
658 NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX |
659 NETIF_F_HW_VLAN_STAG_TX;
666 * compare_vlan_header - Compare two vlan headers
667 * @h1: Pointer to vlan header
668 * @h2: Pointer to vlan header
670 * Compare two vlan headers, returns 0 if equal.
672 * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
674 static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
675 const struct vlan_hdr *h2)
677 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
678 return *(u32 *)h1 ^ *(u32 *)h2;
680 return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
681 ((__force u32)h1->h_vlan_encapsulated_proto ^
682 (__force u32)h2->h_vlan_encapsulated_proto);
685 #endif /* !(_LINUX_IF_VLAN_H_) */