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(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)
88 * struct vlan_pcpu_stats - VLAN percpu rx/tx stats
89 * @rx_packets: number of received packets
90 * @rx_bytes: number of received bytes
91 * @rx_multicast: number of received multicast packets
92 * @tx_packets: number of transmitted packets
93 * @tx_bytes: number of transmitted bytes
94 * @syncp: synchronization point for 64bit counters
95 * @rx_errors: number of rx errors
96 * @tx_dropped: number of tx drops
98 struct vlan_pcpu_stats {
104 struct u64_stats_sync syncp;
109 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
111 extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
112 __be16 vlan_proto, u16 vlan_id);
113 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
114 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
115 extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
118 * struct vlan_priority_tci_mapping - vlan egress priority mappings
119 * @priority: skb priority
120 * @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
121 * @next: pointer to next struct
123 struct vlan_priority_tci_mapping {
126 struct vlan_priority_tci_mapping *next;
129 struct proc_dir_entry;
133 * struct vlan_dev_priv - VLAN private device data
134 * @nr_ingress_mappings: number of ingress priority mappings
135 * @ingress_priority_map: ingress priority mappings
136 * @nr_egress_mappings: number of egress priority mappings
137 * @egress_priority_map: hash of egress priority mappings
138 * @vlan_proto: VLAN encapsulation protocol
139 * @vlan_id: VLAN identifier
140 * @flags: device flags
141 * @real_dev: underlying netdevice
142 * @real_dev_addr: address of underlying netdevice
143 * @dent: proc dir entry
144 * @vlan_pcpu_stats: ptr to percpu rx stats
146 struct vlan_dev_priv {
147 unsigned int nr_ingress_mappings;
148 u32 ingress_priority_map[8];
149 unsigned int nr_egress_mappings;
150 struct vlan_priority_tci_mapping *egress_priority_map[16];
156 struct net_device *real_dev;
157 unsigned char real_dev_addr[ETH_ALEN];
159 struct proc_dir_entry *dent;
160 struct vlan_pcpu_stats __percpu *vlan_pcpu_stats;
161 #ifdef CONFIG_NET_POLL_CONTROLLER
162 struct netpoll *netpoll;
164 unsigned int nest_level;
167 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
169 return netdev_priv(dev);
173 vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
175 struct vlan_priority_tci_mapping *mp;
177 smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
179 mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
181 if (mp->priority == skprio) {
182 return mp->vlan_qos; /* This should already be shifted
183 * to mask correctly with the
191 extern bool vlan_do_receive(struct sk_buff **skb);
193 extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
194 extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
196 extern int vlan_vids_add_by_dev(struct net_device *dev,
197 const struct net_device *by_dev);
198 extern void vlan_vids_del_by_dev(struct net_device *dev,
199 const struct net_device *by_dev);
201 extern bool vlan_uses_dev(const struct net_device *dev);
203 static inline int vlan_get_encap_level(struct net_device *dev)
205 BUG_ON(!is_vlan_dev(dev));
206 return vlan_dev_priv(dev)->nest_level;
209 static inline struct net_device *
210 __vlan_find_dev_deep_rcu(struct net_device *real_dev,
211 __be16 vlan_proto, u16 vlan_id)
216 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
222 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
228 static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
234 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
240 static inline bool vlan_do_receive(struct sk_buff **skb)
245 static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
250 static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
254 static inline int vlan_vids_add_by_dev(struct net_device *dev,
255 const struct net_device *by_dev)
260 static inline void vlan_vids_del_by_dev(struct net_device *dev,
261 const struct net_device *by_dev)
265 static inline bool vlan_uses_dev(const struct net_device *dev)
269 static inline int vlan_get_encap_level(struct net_device *dev)
276 static inline bool vlan_hw_offload_capable(netdev_features_t features,
279 if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
281 if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
287 * __vlan_insert_tag - regular VLAN tag inserting
288 * @skb: skbuff to tag
289 * @vlan_proto: VLAN encapsulation protocol
290 * @vlan_tci: VLAN TCI to insert
292 * Inserts the VLAN tag into @skb as part of the payload
293 * Returns error if skb_cow_head failes.
295 * Does not change skb->protocol so this function can be used during receive.
297 static inline int __vlan_insert_tag(struct sk_buff *skb,
298 __be16 vlan_proto, u16 vlan_tci)
300 struct vlan_ethhdr *veth;
302 if (skb_cow_head(skb, VLAN_HLEN) < 0)
305 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
307 /* Move the mac addresses to the beginning of the new header. */
308 memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN);
309 skb->mac_header -= VLAN_HLEN;
311 /* first, the ethernet type */
312 veth->h_vlan_proto = vlan_proto;
315 veth->h_vlan_TCI = htons(vlan_tci);
321 * vlan_insert_tag - regular VLAN tag inserting
322 * @skb: skbuff to tag
323 * @vlan_proto: VLAN encapsulation protocol
324 * @vlan_tci: VLAN TCI to insert
326 * Inserts the VLAN tag into @skb as part of the payload
327 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
329 * Following the skb_unshare() example, in case of error, the calling function
330 * doesn't have to worry about freeing the original skb.
332 * Does not change skb->protocol so this function can be used during receive.
334 static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
335 __be16 vlan_proto, u16 vlan_tci)
339 err = __vlan_insert_tag(skb, vlan_proto, vlan_tci);
341 dev_kfree_skb_any(skb);
348 * vlan_insert_tag_set_proto - regular VLAN tag inserting
349 * @skb: skbuff to tag
350 * @vlan_proto: VLAN encapsulation protocol
351 * @vlan_tci: VLAN TCI to insert
353 * Inserts the VLAN tag into @skb as part of the payload
354 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
356 * Following the skb_unshare() example, in case of error, the calling function
357 * doesn't have to worry about freeing the original skb.
359 static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
363 skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
365 skb->protocol = vlan_proto;
370 * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
371 * @skb: skbuff to tag
373 * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
375 * Following the skb_unshare() example, in case of error, the calling function
376 * doesn't have to worry about freeing the original skb.
378 static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
380 skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
381 skb_vlan_tag_get(skb));
387 * vlan_hwaccel_push_inside - pushes vlan tag to the payload
388 * @skb: skbuff to tag
390 * Checks is tag is present in @skb->vlan_tci and if it is, it pushes the
391 * 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 if (skb_vlan_tag_present(skb))
399 skb = __vlan_hwaccel_push_inside(skb);
404 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
405 * @skb: skbuff to tag
406 * @vlan_proto: VLAN encapsulation protocol
407 * @vlan_tci: VLAN TCI to insert
409 * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
411 static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
412 __be16 vlan_proto, u16 vlan_tci)
414 skb->vlan_proto = vlan_proto;
415 skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
419 * __vlan_get_tag - get the VLAN ID that is part of the payload
420 * @skb: skbuff to query
421 * @vlan_tci: buffer to store value
423 * Returns error if the skb is not of VLAN type
425 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
427 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
429 if (veth->h_vlan_proto != htons(ETH_P_8021Q) &&
430 veth->h_vlan_proto != htons(ETH_P_8021AD))
433 *vlan_tci = ntohs(veth->h_vlan_TCI);
438 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
439 * @skb: skbuff to query
440 * @vlan_tci: buffer to store value
442 * Returns error if @skb->vlan_tci is not set correctly
444 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
447 if (skb_vlan_tag_present(skb)) {
448 *vlan_tci = skb_vlan_tag_get(skb);
456 #define HAVE_VLAN_GET_TAG
459 * vlan_get_tag - get the VLAN ID from the skb
460 * @skb: skbuff to query
461 * @vlan_tci: buffer to store value
463 * Returns error if the skb is not VLAN tagged
465 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
467 if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
468 return __vlan_hwaccel_get_tag(skb, vlan_tci);
470 return __vlan_get_tag(skb, vlan_tci);
475 * vlan_get_protocol - get protocol EtherType.
476 * @skb: skbuff to query
477 * @type: first vlan protocol
478 * @depth: buffer to store length of eth and vlan tags in bytes
480 * Returns the EtherType of the packet, regardless of whether it is
481 * vlan encapsulated (normal or hardware accelerated) or not.
483 static inline __be16 __vlan_get_protocol(const struct sk_buff *skb, __be16 type,
486 unsigned int vlan_depth = skb->mac_len, parse_depth = VLAN_MAX_DEPTH;
488 /* if type is 802.1Q/AD then the header should already be
489 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
492 if (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
494 if (WARN_ON(vlan_depth < VLAN_HLEN))
496 vlan_depth -= VLAN_HLEN;
498 vlan_depth = ETH_HLEN;
501 struct vlan_hdr vhdr, *vh;
503 vh = skb_header_pointer(skb, vlan_depth, sizeof(vhdr), &vhdr);
504 if (unlikely(!vh || !--parse_depth))
507 type = vh->h_vlan_encapsulated_proto;
508 vlan_depth += VLAN_HLEN;
509 } while (type == htons(ETH_P_8021Q) ||
510 type == htons(ETH_P_8021AD));
520 * vlan_get_protocol - get protocol EtherType.
521 * @skb: skbuff to query
523 * Returns the EtherType of the packet, regardless of whether it is
524 * vlan encapsulated (normal or hardware accelerated) or not.
526 static inline __be16 vlan_get_protocol(const struct sk_buff *skb)
528 return __vlan_get_protocol(skb, skb->protocol, NULL);
531 /* A getter for the SKB protocol field which will handle VLAN tags consistently
532 * whether VLAN acceleration is enabled or not.
534 static inline __be16 skb_protocol(const struct sk_buff *skb, bool skip_vlan)
537 /* VLAN acceleration strips the VLAN header from the skb and
538 * moves it to skb->vlan_proto
540 return skb_vlan_tag_present(skb) ? skb->vlan_proto : skb->protocol;
542 return vlan_get_protocol(skb);
545 static inline void vlan_set_encap_proto(struct sk_buff *skb,
546 struct vlan_hdr *vhdr)
549 unsigned short *rawp;
552 * Was a VLAN packet, grab the encapsulated protocol, which the layer
553 * three protocols care about.
556 proto = vhdr->h_vlan_encapsulated_proto;
557 if (eth_proto_is_802_3(proto)) {
558 skb->protocol = proto;
562 rawp = (unsigned short *)(vhdr + 1);
565 * This is a magic hack to spot IPX packets. Older Novell
566 * breaks the protocol design and runs IPX over 802.3 without
567 * an 802.2 LLC layer. We look for FFFF which isn't a used
568 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
569 * but does for the rest.
571 skb->protocol = htons(ETH_P_802_3);
576 skb->protocol = htons(ETH_P_802_2);
580 * skb_vlan_tagged - check if skb is vlan tagged.
581 * @skb: skbuff to query
583 * Returns true if the skb is tagged, regardless of whether it is hardware
584 * accelerated or not.
586 static inline bool skb_vlan_tagged(const struct sk_buff *skb)
588 if (!skb_vlan_tag_present(skb) &&
589 likely(skb->protocol != htons(ETH_P_8021Q) &&
590 skb->protocol != htons(ETH_P_8021AD)))
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(struct sk_buff *skb)
605 __be16 protocol = skb->protocol;
607 if (!skb_vlan_tag_present(skb)) {
608 struct vlan_ethhdr *veh;
610 if (likely(protocol != htons(ETH_P_8021Q) &&
611 protocol != htons(ETH_P_8021AD)))
614 if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
617 veh = (struct vlan_ethhdr *)skb->data;
618 protocol = veh->h_vlan_encapsulated_proto;
621 if (protocol != htons(ETH_P_8021Q) && protocol != htons(ETH_P_8021AD))
628 * vlan_features_check - drop unsafe features for skb with multiple tags.
629 * @skb: skbuff to query
630 * @features: features to be checked
632 * Returns features without unsafe ones if the skb has multiple tags.
634 static inline netdev_features_t vlan_features_check(struct sk_buff *skb,
635 netdev_features_t features)
637 if (skb_vlan_tagged_multi(skb)) {
638 /* In the case of multi-tagged packets, use a direct mask
639 * instead of using netdev_interesect_features(), to make
640 * sure that only devices supporting NETIF_F_HW_CSUM will
641 * have checksum offloading support.
643 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
644 NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX |
645 NETIF_F_HW_VLAN_STAG_TX;
651 * compare_vlan_header - Compare two vlan headers
652 * @h1: Pointer to vlan header
653 * @h2: Pointer to vlan header
655 * Compare two vlan headers, returns 0 if equal.
657 * Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
659 static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
660 const struct vlan_hdr *h2)
662 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
663 return *(u32 *)h1 ^ *(u32 *)h2;
665 return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
666 ((__force u32)h1->h_vlan_encapsulated_proto ^
667 (__force u32)h2->h_vlan_encapsulated_proto);
670 #endif /* !(_LINUX_IF_VLAN_H_) */