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 */
23 struct vlan_collection;
26 #include <linux/proc_fs.h> /* for proc_dir_entry */
27 #include <linux/netdevice.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 unsigned short h_vlan_proto; /* Should always be 0x8100 */
46 unsigned short h_vlan_TCI; /* Encapsulates priority and VLAN ID */
47 unsigned short h_vlan_encapsulated_proto; /* packet type ID field (or len) */
51 unsigned short h_vlan_TCI; /* Encapsulates priority and VLAN ID */
52 unsigned short h_vlan_encapsulated_proto; /* packet type ID field (or len) */
55 #define VLAN_VID_MASK 0xfff
57 /* found in socket.c */
58 extern void vlan_ioctl_set(int (*hook)(unsigned long));
60 #define VLAN_NAME "vlan"
62 /* if this changes, algorithm will have to be reworked because this
63 * depends on completely exhausting the VLAN identifier space. Thus
64 * it gives constant time look-up, but in many cases it wastes memory.
66 #define VLAN_GROUP_ARRAY_LEN 4096
69 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
70 struct net_device *vlan_devices[VLAN_GROUP_ARRAY_LEN];
72 struct vlan_group *next; /* the next in the list */
75 struct vlan_priority_tci_mapping {
76 unsigned long priority;
77 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
78 * at provisioning time.
79 * ((skb->priority << 13) & 0xE000)
81 struct vlan_priority_tci_mapping *next;
84 /* Holds information that makes sense if this device is a VLAN device. */
85 struct vlan_dev_info {
86 /** This will be the mapping that correlates skb->priority to
87 * 3 bits of VLAN QOS tags...
89 unsigned long ingress_priority_map[8];
90 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
92 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
93 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
94 * VLAN code to move around the ethernet header on
95 * ingress to make the skb look **exactly** like it
96 * came in from an ethernet port. This destroys some of
97 * the VLAN information in the skb, but it fixes programs
98 * like DHCP that use packet-filtering and don't understand
101 struct dev_mc_list *old_mc_list; /* old multi-cast list for the VLAN interface..
102 * we save this so we can tell what changes were
103 * made, in order to feed the right changes down
104 * to the real hardware...
106 int old_allmulti; /* similar to above. */
107 int old_promiscuity; /* similar to above. */
108 struct net_device *real_dev; /* the underlying device/interface */
109 struct proc_dir_entry *dent; /* Holds the proc data */
110 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
111 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
112 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
115 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
117 /* inline functions */
119 static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
121 return &(VLAN_DEV_INFO(dev)->dev_stats);
124 static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
125 unsigned short vlan_tag)
127 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
129 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
132 /* VLAN tx hw acceleration helpers. */
133 struct vlan_skb_tx_cookie {
138 #define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
139 #define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
140 #define vlan_tx_tag_present(__skb) \
141 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
142 #define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
144 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
145 static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
146 struct vlan_group *grp,
147 unsigned short vlan_tag, int polling)
149 struct net_device_stats *stats;
151 skb->real_dev = skb->dev;
152 skb->dev = grp->vlan_devices[vlan_tag & VLAN_VID_MASK];
153 if (skb->dev == NULL) {
156 /* Not NET_RX_DROP, this is not being dropped
162 skb->dev->last_rx = jiffies;
164 stats = vlan_dev_get_stats(skb->dev);
166 stats->rx_bytes += skb->len;
168 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
169 switch (skb->pkt_type) {
170 case PACKET_BROADCAST:
173 case PACKET_MULTICAST:
177 case PACKET_OTHERHOST:
178 /* Our lower layer thinks this is not local, let's make sure.
179 * This allows the VLAN to have a different MAC than the underlying
180 * device, and still route correctly.
182 if (!memcmp(skb->mac.ethernet->h_dest, skb->dev->dev_addr, ETH_ALEN))
183 skb->pkt_type = PACKET_HOST;
187 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
190 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
191 struct vlan_group *grp,
192 unsigned short vlan_tag)
194 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
197 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
198 struct vlan_group *grp,
199 unsigned short vlan_tag)
201 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
205 * __vlan_put_tag - regular VLAN tag inserting
206 * @skb: skbuff to tag
207 * @tag: VLAN tag to insert
209 * Inserts the VLAN tag into @skb as part of the payload
210 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
212 * Following the skb_unshare() example, in case of error, the calling function
213 * doesn't have to worry about freeing the original skb.
215 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
217 struct vlan_ethhdr *veth;
219 if (skb_headroom(skb) < VLAN_HLEN) {
220 struct sk_buff *sk_tmp = skb;
221 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
224 printk(KERN_ERR "vlan: failed to realloc headroom\n");
228 skb = skb_unshare(skb, GFP_ATOMIC);
230 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
235 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
237 /* Move the mac addresses to the beginning of the new header. */
238 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
240 /* first, the ethernet type */
241 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
244 veth->h_vlan_TCI = htons(tag);
246 skb->protocol = __constant_htons(ETH_P_8021Q);
247 skb->mac.raw -= VLAN_HLEN;
248 skb->nh.raw -= VLAN_HLEN;
254 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
255 * @skb: skbuff to tag
256 * @tag: VLAN tag to insert
258 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
260 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
262 struct vlan_skb_tx_cookie *cookie;
264 cookie = VLAN_TX_SKB_CB(skb);
265 cookie->magic = VLAN_TX_COOKIE_MAGIC;
266 cookie->vlan_tag = tag;
271 #define HAVE_VLAN_PUT_TAG
274 * vlan_put_tag - inserts VLAN tag according to device features
275 * @skb: skbuff to tag
276 * @tag: VLAN tag to insert
278 * Assumes skb->dev is the target that will xmit this frame.
279 * Returns a VLAN tagged skb.
281 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
283 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
284 return __vlan_hwaccel_put_tag(skb, tag);
286 return __vlan_put_tag(skb, tag);
291 * __vlan_get_tag - get the VLAN ID that is part of the payload
292 * @skb: skbuff to query
293 * @tag: buffer to store vlaue
295 * Returns error if the skb is not of VLAN type
297 static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
299 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
301 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
305 *tag = ntohs(veth->h_vlan_TCI);
311 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
312 * @skb: skbuff to query
313 * @tag: buffer to store vlaue
315 * Returns error if @skb->cb[] is not set correctly
317 static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
319 struct vlan_skb_tx_cookie *cookie;
321 cookie = VLAN_TX_SKB_CB(skb);
322 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
323 *tag = cookie->vlan_tag;
331 #define HAVE_VLAN_GET_TAG
334 * vlan_get_tag - get the VLAN ID from the skb
335 * @skb: skbuff to query
336 * @tag: buffer to store vlaue
338 * Returns error if the skb is not VLAN tagged
340 static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
342 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
343 return __vlan_hwaccel_get_tag(skb, tag);
345 return __vlan_get_tag(skb, tag);
349 #endif /* __KERNEL__ */
351 /* VLAN IOCTLs are found in sockios.h */
353 /* Passed in vlan_ioctl_args structure to determine behaviour. */
354 enum vlan_ioctl_cmds {
357 SET_VLAN_INGRESS_PRIORITY_CMD,
358 SET_VLAN_EGRESS_PRIORITY_CMD,
359 GET_VLAN_INGRESS_PRIORITY_CMD,
360 GET_VLAN_EGRESS_PRIORITY_CMD,
361 SET_VLAN_NAME_TYPE_CMD,
365 enum vlan_name_types {
366 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
367 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
368 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
369 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
370 VLAN_NAME_TYPE_HIGHEST
373 struct vlan_ioctl_args {
374 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
380 unsigned int skb_priority;
381 unsigned int name_type;
382 unsigned int bind_type;
383 unsigned int flag; /* Matches vlan_dev_info flags */
389 #endif /* !(_LINUX_IF_VLAN_H_) */