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.
13 #ifndef _LINUX_IF_VLAN_H_
14 #define _LINUX_IF_VLAN_H_
18 /* externally defined structs */
22 struct vlan_collection;
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
29 #define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header)
32 #define VLAN_ETH_ALEN 6 /* Octets in one ethernet addr */
33 #define VLAN_ETH_HLEN 18 /* Total octets in header. */
34 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
37 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
39 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
40 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
43 unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
44 unsigned char h_source[ETH_ALEN]; /* source ether addr */
45 __be16 h_vlan_proto; /* Should always be 0x8100 */
46 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
47 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
50 #include <linux/skbuff.h>
52 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
54 return (struct vlan_ethhdr *)skb_mac_header(skb);
58 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
59 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
62 #define VLAN_VID_MASK 0xfff
64 /* found in socket.c */
65 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
67 #define VLAN_NAME "vlan"
69 /* if this changes, algorithm will have to be reworked because this
70 * depends on completely exhausting the VLAN identifier space. Thus
71 * it gives constant time look-up, but in many cases it wastes memory.
73 #define VLAN_GROUP_ARRAY_LEN 4096
74 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8
75 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)
78 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
79 struct hlist_node hlist; /* linked list */
80 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
84 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
87 struct net_device **array;
88 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
89 return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN];
92 static inline void vlan_group_set_device(struct vlan_group *vg,
94 struct net_device *dev)
96 struct net_device **array;
99 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
100 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
103 struct vlan_priority_tci_mapping {
105 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
106 * at provisioning time.
107 * ((skb->priority << 13) & 0xE000)
109 struct vlan_priority_tci_mapping *next;
112 /* Holds information that makes sense if this device is a VLAN device. */
113 struct vlan_dev_info {
114 /** This will be the mapping that correlates skb->priority to
115 * 3 bits of VLAN QOS tags...
117 unsigned int nr_ingress_mappings;
118 u32 ingress_priority_map[8];
120 unsigned int nr_egress_mappings;
121 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
123 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
124 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
125 * VLAN code to move around the ethernet header on
126 * ingress to make the skb look **exactly** like it
127 * came in from an ethernet port. This destroys some of
128 * the VLAN information in the skb, but it fixes programs
129 * like DHCP that use packet-filtering and don't understand
132 struct net_device *real_dev; /* the underlying device/interface */
133 unsigned char real_dev_addr[ETH_ALEN];
134 struct proc_dir_entry *dent; /* Holds the proc data */
135 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
136 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
137 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
140 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
142 /* inline functions */
144 static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
146 return &(VLAN_DEV_INFO(dev)->dev_stats);
149 static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
150 unsigned short vlan_tag)
152 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
154 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
157 /* VLAN tx hw acceleration helpers. */
158 struct vlan_skb_tx_cookie {
163 #define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
164 #define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
165 #define vlan_tx_tag_present(__skb) \
166 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
167 #define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
169 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
170 static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
171 struct vlan_group *grp,
172 unsigned short vlan_tag, int polling)
174 struct net_device_stats *stats;
176 if (skb_bond_should_drop(skb)) {
177 dev_kfree_skb_any(skb);
181 skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
182 if (skb->dev == NULL) {
183 dev_kfree_skb_any(skb);
185 /* Not NET_RX_DROP, this is not being dropped
191 skb->dev->last_rx = jiffies;
193 stats = vlan_dev_get_stats(skb->dev);
195 stats->rx_bytes += skb->len;
197 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
198 switch (skb->pkt_type) {
199 case PACKET_BROADCAST:
202 case PACKET_MULTICAST:
206 case PACKET_OTHERHOST:
207 /* Our lower layer thinks this is not local, let's make sure.
208 * This allows the VLAN to have a different MAC than the underlying
209 * device, and still route correctly.
211 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
213 skb->pkt_type = PACKET_HOST;
217 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
220 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
221 struct vlan_group *grp,
222 unsigned short vlan_tag)
224 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
227 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
228 struct vlan_group *grp,
229 unsigned short vlan_tag)
231 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
235 * __vlan_put_tag - regular VLAN tag inserting
236 * @skb: skbuff to tag
237 * @tag: VLAN tag to insert
239 * Inserts the VLAN tag into @skb as part of the payload
240 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
242 * Following the skb_unshare() example, in case of error, the calling function
243 * doesn't have to worry about freeing the original skb.
245 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
247 struct vlan_ethhdr *veth;
249 if (skb_headroom(skb) < VLAN_HLEN) {
250 struct sk_buff *sk_tmp = skb;
251 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
254 printk(KERN_ERR "vlan: failed to realloc headroom\n");
258 skb = skb_unshare(skb, GFP_ATOMIC);
260 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
265 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
267 /* Move the mac addresses to the beginning of the new header. */
268 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
270 /* first, the ethernet type */
271 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
274 veth->h_vlan_TCI = htons(tag);
276 skb->protocol = __constant_htons(ETH_P_8021Q);
277 skb->mac_header -= VLAN_HLEN;
278 skb->network_header -= VLAN_HLEN;
284 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
285 * @skb: skbuff to tag
286 * @tag: VLAN tag to insert
288 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
290 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
292 struct vlan_skb_tx_cookie *cookie;
294 cookie = VLAN_TX_SKB_CB(skb);
295 cookie->magic = VLAN_TX_COOKIE_MAGIC;
296 cookie->vlan_tag = tag;
301 #define HAVE_VLAN_PUT_TAG
304 * vlan_put_tag - inserts VLAN tag according to device features
305 * @skb: skbuff to tag
306 * @tag: VLAN tag to insert
308 * Assumes skb->dev is the target that will xmit this frame.
309 * Returns a VLAN tagged skb.
311 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
313 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
314 return __vlan_hwaccel_put_tag(skb, tag);
316 return __vlan_put_tag(skb, tag);
321 * __vlan_get_tag - get the VLAN ID that is part of the payload
322 * @skb: skbuff to query
323 * @tag: buffer to store vlaue
325 * Returns error if the skb is not of VLAN type
327 static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
329 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
331 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
335 *tag = ntohs(veth->h_vlan_TCI);
341 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
342 * @skb: skbuff to query
343 * @tag: buffer to store vlaue
345 * Returns error if @skb->cb[] is not set correctly
347 static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
349 struct vlan_skb_tx_cookie *cookie;
351 cookie = VLAN_TX_SKB_CB(skb);
352 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
353 *tag = cookie->vlan_tag;
361 #define HAVE_VLAN_GET_TAG
364 * vlan_get_tag - get the VLAN ID from the skb
365 * @skb: skbuff to query
366 * @tag: buffer to store vlaue
368 * Returns error if the skb is not VLAN tagged
370 static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
372 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
373 return __vlan_hwaccel_get_tag(skb, tag);
375 return __vlan_get_tag(skb, tag);
379 #endif /* __KERNEL__ */
381 /* VLAN IOCTLs are found in sockios.h */
383 /* Passed in vlan_ioctl_args structure to determine behaviour. */
384 enum vlan_ioctl_cmds {
387 SET_VLAN_INGRESS_PRIORITY_CMD,
388 SET_VLAN_EGRESS_PRIORITY_CMD,
389 GET_VLAN_INGRESS_PRIORITY_CMD,
390 GET_VLAN_EGRESS_PRIORITY_CMD,
391 SET_VLAN_NAME_TYPE_CMD,
393 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
394 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
398 VLAN_FLAG_REORDER_HDR = 0x1,
401 enum vlan_name_types {
402 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
403 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
404 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
405 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
406 VLAN_NAME_TYPE_HIGHEST
409 struct vlan_ioctl_args {
410 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
416 unsigned int skb_priority;
417 unsigned int name_type;
418 unsigned int bind_type;
419 unsigned int flag; /* Matches vlan_dev_info flags */
425 #endif /* !(_LINUX_IF_VLAN_H_) */