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 */
21 #include <linux/netdevice.h>
22 #include <linux/etherdevice.h>
24 #define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header)
27 #define VLAN_ETH_ALEN 6 /* Octets in one ethernet addr */
28 #define VLAN_ETH_HLEN 18 /* Total octets in header. */
29 #define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
32 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
34 #define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
35 #define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
38 unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
39 unsigned char h_source[ETH_ALEN]; /* source ether addr */
40 __be16 h_vlan_proto; /* Should always be 0x8100 */
41 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
42 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
45 #include <linux/skbuff.h>
47 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
49 return (struct vlan_ethhdr *)skb_mac_header(skb);
53 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
54 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
57 #define VLAN_VID_MASK 0xfff
59 /* found in socket.c */
60 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
62 #define VLAN_NAME "vlan"
64 /* if this changes, algorithm will have to be reworked because this
65 * depends on completely exhausting the VLAN identifier space. Thus
66 * it gives constant time look-up, but in many cases it wastes memory.
68 #define VLAN_GROUP_ARRAY_LEN 4096
69 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8
70 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)
73 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
74 struct hlist_node hlist; /* linked list */
75 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
79 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
82 struct net_device **array;
83 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
84 return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN];
87 static inline void vlan_group_set_device(struct vlan_group *vg,
89 struct net_device *dev)
91 struct net_device **array;
94 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
95 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
98 struct vlan_priority_tci_mapping {
100 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
101 * at provisioning time.
102 * ((skb->priority << 13) & 0xE000)
104 struct vlan_priority_tci_mapping *next;
107 /* Holds information that makes sense if this device is a VLAN device. */
108 struct vlan_dev_info {
109 /** This will be the mapping that correlates skb->priority to
110 * 3 bits of VLAN QOS tags...
112 unsigned int nr_ingress_mappings;
113 u32 ingress_priority_map[8];
115 unsigned int nr_egress_mappings;
116 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
118 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
119 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
120 * VLAN code to move around the ethernet header on
121 * ingress to make the skb look **exactly** like it
122 * came in from an ethernet port. This destroys some of
123 * the VLAN information in the skb, but it fixes programs
124 * like DHCP that use packet-filtering and don't understand
127 struct net_device *real_dev; /* the underlying device/interface */
128 unsigned char real_dev_addr[ETH_ALEN];
129 struct proc_dir_entry *dent; /* Holds the proc data */
130 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
131 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
132 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
135 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
137 /* inline functions */
139 static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
141 return &(VLAN_DEV_INFO(dev)->dev_stats);
144 static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
145 unsigned short vlan_tag)
147 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
149 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
152 /* VLAN tx hw acceleration helpers. */
153 struct vlan_skb_tx_cookie {
158 #define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
159 #define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
160 #define vlan_tx_tag_present(__skb) \
161 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
162 #define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
164 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
165 static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
166 struct vlan_group *grp,
167 unsigned short vlan_tag, int polling)
169 struct net_device_stats *stats;
171 if (skb_bond_should_drop(skb)) {
172 dev_kfree_skb_any(skb);
176 skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
177 if (skb->dev == NULL) {
178 dev_kfree_skb_any(skb);
180 /* Not NET_RX_DROP, this is not being dropped
186 skb->dev->last_rx = jiffies;
188 stats = vlan_dev_get_stats(skb->dev);
190 stats->rx_bytes += skb->len;
192 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
193 switch (skb->pkt_type) {
194 case PACKET_BROADCAST:
197 case PACKET_MULTICAST:
201 case PACKET_OTHERHOST:
202 /* Our lower layer thinks this is not local, let's make sure.
203 * This allows the VLAN to have a different MAC than the underlying
204 * device, and still route correctly.
206 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
208 skb->pkt_type = PACKET_HOST;
212 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
215 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
216 struct vlan_group *grp,
217 unsigned short vlan_tag)
219 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
222 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
223 struct vlan_group *grp,
224 unsigned short vlan_tag)
226 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
230 * __vlan_put_tag - regular VLAN tag inserting
231 * @skb: skbuff to tag
232 * @tag: VLAN tag to insert
234 * Inserts the VLAN tag into @skb as part of the payload
235 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
237 * Following the skb_unshare() example, in case of error, the calling function
238 * doesn't have to worry about freeing the original skb.
240 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
242 struct vlan_ethhdr *veth;
244 if (skb_headroom(skb) < VLAN_HLEN) {
245 struct sk_buff *sk_tmp = skb;
246 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
249 printk(KERN_ERR "vlan: failed to realloc headroom\n");
253 skb = skb_unshare(skb, GFP_ATOMIC);
255 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
260 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
262 /* Move the mac addresses to the beginning of the new header. */
263 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
265 /* first, the ethernet type */
266 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
269 veth->h_vlan_TCI = htons(tag);
271 skb->protocol = __constant_htons(ETH_P_8021Q);
272 skb->mac_header -= VLAN_HLEN;
273 skb->network_header -= VLAN_HLEN;
279 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
280 * @skb: skbuff to tag
281 * @tag: VLAN tag to insert
283 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
285 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
287 struct vlan_skb_tx_cookie *cookie;
289 cookie = VLAN_TX_SKB_CB(skb);
290 cookie->magic = VLAN_TX_COOKIE_MAGIC;
291 cookie->vlan_tag = tag;
296 #define HAVE_VLAN_PUT_TAG
299 * vlan_put_tag - inserts VLAN tag according to device features
300 * @skb: skbuff to tag
301 * @tag: VLAN tag to insert
303 * Assumes skb->dev is the target that will xmit this frame.
304 * Returns a VLAN tagged skb.
306 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
308 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
309 return __vlan_hwaccel_put_tag(skb, tag);
311 return __vlan_put_tag(skb, tag);
316 * __vlan_get_tag - get the VLAN ID that is part of the payload
317 * @skb: skbuff to query
318 * @tag: buffer to store vlaue
320 * Returns error if the skb is not of VLAN type
322 static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
324 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
326 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
330 *tag = ntohs(veth->h_vlan_TCI);
336 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
337 * @skb: skbuff to query
338 * @tag: buffer to store vlaue
340 * Returns error if @skb->cb[] is not set correctly
342 static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
344 struct vlan_skb_tx_cookie *cookie;
346 cookie = VLAN_TX_SKB_CB(skb);
347 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
348 *tag = cookie->vlan_tag;
356 #define HAVE_VLAN_GET_TAG
359 * vlan_get_tag - get the VLAN ID from the skb
360 * @skb: skbuff to query
361 * @tag: buffer to store vlaue
363 * Returns error if the skb is not VLAN tagged
365 static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
367 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
368 return __vlan_hwaccel_get_tag(skb, tag);
370 return __vlan_get_tag(skb, tag);
374 #endif /* __KERNEL__ */
376 /* VLAN IOCTLs are found in sockios.h */
378 /* Passed in vlan_ioctl_args structure to determine behaviour. */
379 enum vlan_ioctl_cmds {
382 SET_VLAN_INGRESS_PRIORITY_CMD,
383 SET_VLAN_EGRESS_PRIORITY_CMD,
384 GET_VLAN_INGRESS_PRIORITY_CMD,
385 GET_VLAN_EGRESS_PRIORITY_CMD,
386 SET_VLAN_NAME_TYPE_CMD,
388 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
389 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
393 VLAN_FLAG_REORDER_HDR = 0x1,
396 enum vlan_name_types {
397 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
398 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
399 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
400 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
401 VLAN_NAME_TYPE_HIGHEST
404 struct vlan_ioctl_args {
405 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
411 unsigned int skb_priority;
412 unsigned int name_type;
413 unsigned int bind_type;
414 unsigned int flag; /* Matches vlan_dev_info flags */
420 #endif /* !(_LINUX_IF_VLAN_H_) */