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 * struct vlan_hdr - vlan header
39 * @h_vlan_TCI: priority and VLAN ID
40 * @h_vlan_encapsulated_proto: packet type ID or len
44 __be16 h_vlan_encapsulated_proto;
48 * struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
49 * @h_dest: destination ethernet address
50 * @h_source: source ethernet address
51 * @h_vlan_proto: ethernet protocol (always 0x8100)
52 * @h_vlan_TCI: priority and VLAN ID
53 * @h_vlan_encapsulated_proto: packet type ID or len
56 unsigned char h_dest[ETH_ALEN];
57 unsigned char h_source[ETH_ALEN];
60 __be16 h_vlan_encapsulated_proto;
63 #include <linux/skbuff.h>
65 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
67 return (struct vlan_ethhdr *)skb_mac_header(skb);
70 #define VLAN_VID_MASK 0xfff
72 /* found in socket.c */
73 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
75 /* if this changes, algorithm will have to be reworked because this
76 * depends on completely exhausting the VLAN identifier space. Thus
77 * it gives constant time look-up, but in many cases it wastes memory.
79 #define VLAN_GROUP_ARRAY_LEN 4096
80 #define VLAN_GROUP_ARRAY_SPLIT_PARTS 8
81 #define VLAN_GROUP_ARRAY_PART_LEN (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)
84 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
85 struct hlist_node hlist; /* linked list */
86 struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
90 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
93 struct net_device **array;
94 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
95 return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN];
98 static inline void vlan_group_set_device(struct vlan_group *vg,
100 struct net_device *dev)
102 struct net_device **array;
105 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
106 array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
109 struct vlan_priority_tci_mapping {
111 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
112 * at provisioning time.
113 * ((skb->priority << 13) & 0xE000)
115 struct vlan_priority_tci_mapping *next;
118 /* Holds information that makes sense if this device is a VLAN device. */
119 struct vlan_dev_info {
120 /** This will be the mapping that correlates skb->priority to
121 * 3 bits of VLAN QOS tags...
123 unsigned int nr_ingress_mappings;
124 u32 ingress_priority_map[8];
126 unsigned int nr_egress_mappings;
127 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
129 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
130 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
131 * VLAN code to move around the ethernet header on
132 * ingress to make the skb look **exactly** like it
133 * came in from an ethernet port. This destroys some of
134 * the VLAN information in the skb, but it fixes programs
135 * like DHCP that use packet-filtering and don't understand
138 struct net_device *real_dev; /* the underlying device/interface */
139 unsigned char real_dev_addr[ETH_ALEN];
140 struct proc_dir_entry *dent; /* Holds the proc data */
141 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
142 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
143 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
146 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
148 /* inline functions */
150 static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
152 return &(VLAN_DEV_INFO(dev)->dev_stats);
155 static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
156 unsigned short vlan_tag)
158 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
160 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
163 /* VLAN tx hw acceleration helpers. */
164 struct vlan_skb_tx_cookie {
169 #define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
170 #define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
171 #define vlan_tx_tag_present(__skb) \
172 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
173 #define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
175 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
176 static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
177 struct vlan_group *grp,
178 unsigned short vlan_tag, int polling)
180 struct net_device_stats *stats;
182 if (skb_bond_should_drop(skb)) {
183 dev_kfree_skb_any(skb);
187 skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
188 if (skb->dev == NULL) {
189 dev_kfree_skb_any(skb);
191 /* Not NET_RX_DROP, this is not being dropped
197 skb->dev->last_rx = jiffies;
199 stats = vlan_dev_get_stats(skb->dev);
201 stats->rx_bytes += skb->len;
203 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
204 switch (skb->pkt_type) {
205 case PACKET_BROADCAST:
208 case PACKET_MULTICAST:
212 case PACKET_OTHERHOST:
213 /* Our lower layer thinks this is not local, let's make sure.
214 * This allows the VLAN to have a different MAC than the underlying
215 * device, and still route correctly.
217 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
219 skb->pkt_type = PACKET_HOST;
223 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
226 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
227 struct vlan_group *grp,
228 unsigned short vlan_tag)
230 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
233 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
234 struct vlan_group *grp,
235 unsigned short vlan_tag)
237 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
241 * __vlan_put_tag - regular VLAN tag inserting
242 * @skb: skbuff to tag
243 * @tag: VLAN tag to insert
245 * Inserts the VLAN tag into @skb as part of the payload
246 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
248 * Following the skb_unshare() example, in case of error, the calling function
249 * doesn't have to worry about freeing the original skb.
251 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
253 struct vlan_ethhdr *veth;
255 if (skb_headroom(skb) < VLAN_HLEN) {
256 struct sk_buff *sk_tmp = skb;
257 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
260 printk(KERN_ERR "vlan: failed to realloc headroom\n");
264 skb = skb_unshare(skb, GFP_ATOMIC);
266 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
271 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
273 /* Move the mac addresses to the beginning of the new header. */
274 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
276 /* first, the ethernet type */
277 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
280 veth->h_vlan_TCI = htons(tag);
282 skb->protocol = __constant_htons(ETH_P_8021Q);
283 skb->mac_header -= VLAN_HLEN;
284 skb->network_header -= VLAN_HLEN;
290 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
291 * @skb: skbuff to tag
292 * @tag: VLAN tag to insert
294 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
296 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
298 struct vlan_skb_tx_cookie *cookie;
300 cookie = VLAN_TX_SKB_CB(skb);
301 cookie->magic = VLAN_TX_COOKIE_MAGIC;
302 cookie->vlan_tag = tag;
307 #define HAVE_VLAN_PUT_TAG
310 * vlan_put_tag - inserts VLAN tag according to device features
311 * @skb: skbuff to tag
312 * @tag: VLAN tag to insert
314 * Assumes skb->dev is the target that will xmit this frame.
315 * Returns a VLAN tagged skb.
317 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
319 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
320 return __vlan_hwaccel_put_tag(skb, tag);
322 return __vlan_put_tag(skb, tag);
327 * __vlan_get_tag - get the VLAN ID that is part of the payload
328 * @skb: skbuff to query
329 * @tag: buffer to store vlaue
331 * Returns error if the skb is not of VLAN type
333 static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
335 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
337 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
341 *tag = ntohs(veth->h_vlan_TCI);
347 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
348 * @skb: skbuff to query
349 * @tag: buffer to store vlaue
351 * Returns error if @skb->cb[] is not set correctly
353 static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
355 struct vlan_skb_tx_cookie *cookie;
357 cookie = VLAN_TX_SKB_CB(skb);
358 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
359 *tag = cookie->vlan_tag;
367 #define HAVE_VLAN_GET_TAG
370 * vlan_get_tag - get the VLAN ID from the skb
371 * @skb: skbuff to query
372 * @tag: buffer to store vlaue
374 * Returns error if the skb is not VLAN tagged
376 static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
378 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
379 return __vlan_hwaccel_get_tag(skb, tag);
381 return __vlan_get_tag(skb, tag);
385 #endif /* __KERNEL__ */
387 /* VLAN IOCTLs are found in sockios.h */
389 /* Passed in vlan_ioctl_args structure to determine behaviour. */
390 enum vlan_ioctl_cmds {
393 SET_VLAN_INGRESS_PRIORITY_CMD,
394 SET_VLAN_EGRESS_PRIORITY_CMD,
395 GET_VLAN_INGRESS_PRIORITY_CMD,
396 GET_VLAN_EGRESS_PRIORITY_CMD,
397 SET_VLAN_NAME_TYPE_CMD,
399 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
400 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
404 VLAN_FLAG_REORDER_HDR = 0x1,
407 enum vlan_name_types {
408 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
409 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
410 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
411 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
412 VLAN_NAME_TYPE_HIGHEST
415 struct vlan_ioctl_args {
416 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
422 unsigned int skb_priority;
423 unsigned int name_type;
424 unsigned int bind_type;
425 unsigned int flag; /* Matches vlan_dev_info flags */
431 #endif /* !(_LINUX_IF_VLAN_H_) */