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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * VLAN An implementation of 802.1Q VLAN tagging.
3 *
4 * Authors: Ben Greear <greearb@candelatech.com>
5 *
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.
10 *
11 */
12
13#ifndef _LINUX_IF_VLAN_H_
14#define _LINUX_IF_VLAN_H_
15
16#ifdef __KERNEL__
17
18/* externally defined structs */
19struct vlan_group;
20struct net_device;
21struct packet_type;
22struct vlan_collection;
23struct vlan_dev_info;
24struct hlist_node;
25
26#include <linux/proc_fs.h> /* for proc_dir_entry */
27#include <linux/netdevice.h>
28
29#define VLAN_HLEN 4 /* The additional bytes (on top of the Ethernet header)
30 * that VLAN requires.
31 */
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 */
35
36/*
37 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
38 */
39#define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
40#define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
41
42struct vlan_ethhdr {
43 unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
44 unsigned char h_source[ETH_ALEN]; /* source ether addr */
Alexey Dobriyan3c3f8f22005-09-19 15:41:28 -070045 __be16 h_vlan_proto; /* Should always be 0x8100 */
46 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 unsigned short h_vlan_encapsulated_proto; /* packet type ID field (or len) */
48};
49
50#include <linux/skbuff.h>
51
52static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
53{
54 return (struct vlan_ethhdr *)skb->mac.raw;
55}
56
57struct vlan_hdr {
Alexey Dobriyan3c3f8f22005-09-19 15:41:28 -070058 __be16 h_vlan_TCI; /* Encapsulates priority and VLAN ID */
59 __be16 h_vlan_encapsulated_proto; /* packet type ID field (or len) */
Linus Torvalds1da177e2005-04-16 15:20:36 -070060};
61
62#define VLAN_VID_MASK 0xfff
63
64/* found in socket.c */
65extern void vlan_ioctl_set(int (*hook)(void __user *));
66
67#define VLAN_NAME "vlan"
68
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.
72 */
73#define VLAN_GROUP_ARRAY_LEN 4096
74
75struct vlan_group {
76 int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
77 struct hlist_node hlist; /* linked list */
78 struct net_device *vlan_devices[VLAN_GROUP_ARRAY_LEN];
79 struct rcu_head rcu;
80};
81
82struct vlan_priority_tci_mapping {
83 unsigned long priority;
84 unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
85 * at provisioning time.
86 * ((skb->priority << 13) & 0xE000)
87 */
88 struct vlan_priority_tci_mapping *next;
89};
90
91/* Holds information that makes sense if this device is a VLAN device. */
92struct vlan_dev_info {
93 /** This will be the mapping that correlates skb->priority to
94 * 3 bits of VLAN QOS tags...
95 */
96 unsigned long ingress_priority_map[8];
97 struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
98
99 unsigned short vlan_id; /* The VLAN Identifier for this interface. */
100 unsigned short flags; /* (1 << 0) re_order_header This option will cause the
101 * VLAN code to move around the ethernet header on
102 * ingress to make the skb look **exactly** like it
103 * came in from an ethernet port. This destroys some of
104 * the VLAN information in the skb, but it fixes programs
105 * like DHCP that use packet-filtering and don't understand
106 * 802.1Q
107 */
108 struct dev_mc_list *old_mc_list; /* old multi-cast list for the VLAN interface..
109 * we save this so we can tell what changes were
110 * made, in order to feed the right changes down
111 * to the real hardware...
112 */
113 int old_allmulti; /* similar to above. */
114 int old_promiscuity; /* similar to above. */
115 struct net_device *real_dev; /* the underlying device/interface */
116 struct proc_dir_entry *dent; /* Holds the proc data */
117 unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
118 unsigned long cnt_encap_on_xmit; /* How many times did we have to encapsulate the skb on TX. */
119 struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
120};
121
122#define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
123
124/* inline functions */
125
126static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
127{
128 return &(VLAN_DEV_INFO(dev)->dev_stats);
129}
130
131static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
132 unsigned short vlan_tag)
133{
134 struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
135
136 return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
137}
138
139/* VLAN tx hw acceleration helpers. */
140struct vlan_skb_tx_cookie {
141 u32 magic;
142 u32 vlan_tag;
143};
144
145#define VLAN_TX_COOKIE_MAGIC 0x564c414e /* "VLAN" in ascii. */
146#define VLAN_TX_SKB_CB(__skb) ((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
147#define vlan_tx_tag_present(__skb) \
148 (VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
149#define vlan_tx_tag_get(__skb) (VLAN_TX_SKB_CB(__skb)->vlan_tag)
150
151/* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
152static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
153 struct vlan_group *grp,
154 unsigned short vlan_tag, int polling)
155{
156 struct net_device_stats *stats;
157
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 skb->dev = grp->vlan_devices[vlan_tag & VLAN_VID_MASK];
159 if (skb->dev == NULL) {
160 dev_kfree_skb_any(skb);
161
162 /* Not NET_RX_DROP, this is not being dropped
163 * due to congestion.
164 */
165 return 0;
166 }
167
168 skb->dev->last_rx = jiffies;
169
170 stats = vlan_dev_get_stats(skb->dev);
171 stats->rx_packets++;
172 stats->rx_bytes += skb->len;
173
174 skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
175 switch (skb->pkt_type) {
176 case PACKET_BROADCAST:
177 break;
178
179 case PACKET_MULTICAST:
180 stats->multicast++;
181 break;
182
183 case PACKET_OTHERHOST:
184 /* Our lower layer thinks this is not local, let's make sure.
185 * This allows the VLAN to have a different MAC than the underlying
186 * device, and still route correctly.
187 */
188 if (!memcmp(eth_hdr(skb)->h_dest, skb->dev->dev_addr, ETH_ALEN))
189 skb->pkt_type = PACKET_HOST;
190 break;
191 };
192
193 return (polling ? netif_receive_skb(skb) : netif_rx(skb));
194}
195
196static inline int vlan_hwaccel_rx(struct sk_buff *skb,
197 struct vlan_group *grp,
198 unsigned short vlan_tag)
199{
200 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
201}
202
203static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
204 struct vlan_group *grp,
205 unsigned short vlan_tag)
206{
207 return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
208}
209
210/**
211 * __vlan_put_tag - regular VLAN tag inserting
212 * @skb: skbuff to tag
213 * @tag: VLAN tag to insert
214 *
215 * Inserts the VLAN tag into @skb as part of the payload
216 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
217 *
218 * Following the skb_unshare() example, in case of error, the calling function
219 * doesn't have to worry about freeing the original skb.
220 */
221static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
222{
223 struct vlan_ethhdr *veth;
224
225 if (skb_headroom(skb) < VLAN_HLEN) {
226 struct sk_buff *sk_tmp = skb;
227 skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
228 kfree_skb(sk_tmp);
229 if (!skb) {
230 printk(KERN_ERR "vlan: failed to realloc headroom\n");
231 return NULL;
232 }
233 } else {
234 skb = skb_unshare(skb, GFP_ATOMIC);
235 if (!skb) {
236 printk(KERN_ERR "vlan: failed to unshare skbuff\n");
237 return NULL;
238 }
239 }
240
241 veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
242
243 /* Move the mac addresses to the beginning of the new header. */
244 memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
245
246 /* first, the ethernet type */
247 veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);
248
249 /* now, the tag */
250 veth->h_vlan_TCI = htons(tag);
251
252 skb->protocol = __constant_htons(ETH_P_8021Q);
253 skb->mac.raw -= VLAN_HLEN;
254 skb->nh.raw -= VLAN_HLEN;
255
256 return skb;
257}
258
259/**
260 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
261 * @skb: skbuff to tag
262 * @tag: VLAN tag to insert
263 *
264 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
265 */
266static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
267{
268 struct vlan_skb_tx_cookie *cookie;
269
270 cookie = VLAN_TX_SKB_CB(skb);
271 cookie->magic = VLAN_TX_COOKIE_MAGIC;
272 cookie->vlan_tag = tag;
273
274 return skb;
275}
276
277#define HAVE_VLAN_PUT_TAG
278
279/**
280 * vlan_put_tag - inserts VLAN tag according to device features
281 * @skb: skbuff to tag
282 * @tag: VLAN tag to insert
283 *
284 * Assumes skb->dev is the target that will xmit this frame.
285 * Returns a VLAN tagged skb.
286 */
287static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
288{
289 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
290 return __vlan_hwaccel_put_tag(skb, tag);
291 } else {
292 return __vlan_put_tag(skb, tag);
293 }
294}
295
296/**
297 * __vlan_get_tag - get the VLAN ID that is part of the payload
298 * @skb: skbuff to query
299 * @tag: buffer to store vlaue
300 *
301 * Returns error if the skb is not of VLAN type
302 */
303static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
304{
305 struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
306
307 if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
308 return -EINVAL;
309 }
310
311 *tag = ntohs(veth->h_vlan_TCI);
312
313 return 0;
314}
315
316/**
317 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
318 * @skb: skbuff to query
319 * @tag: buffer to store vlaue
320 *
321 * Returns error if @skb->cb[] is not set correctly
322 */
323static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
324{
325 struct vlan_skb_tx_cookie *cookie;
326
327 cookie = VLAN_TX_SKB_CB(skb);
328 if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
329 *tag = cookie->vlan_tag;
330 return 0;
331 } else {
332 *tag = 0;
333 return -EINVAL;
334 }
335}
336
337#define HAVE_VLAN_GET_TAG
338
339/**
340 * vlan_get_tag - get the VLAN ID from the skb
341 * @skb: skbuff to query
342 * @tag: buffer to store vlaue
343 *
344 * Returns error if the skb is not VLAN tagged
345 */
346static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
347{
348 if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
349 return __vlan_hwaccel_get_tag(skb, tag);
350 } else {
351 return __vlan_get_tag(skb, tag);
352 }
353}
354
355#endif /* __KERNEL__ */
356
357/* VLAN IOCTLs are found in sockios.h */
358
359/* Passed in vlan_ioctl_args structure to determine behaviour. */
360enum vlan_ioctl_cmds {
361 ADD_VLAN_CMD,
362 DEL_VLAN_CMD,
363 SET_VLAN_INGRESS_PRIORITY_CMD,
364 SET_VLAN_EGRESS_PRIORITY_CMD,
365 GET_VLAN_INGRESS_PRIORITY_CMD,
366 GET_VLAN_EGRESS_PRIORITY_CMD,
367 SET_VLAN_NAME_TYPE_CMD,
368 SET_VLAN_FLAG_CMD,
369 GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
370 GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
371};
372
373enum vlan_name_types {
374 VLAN_NAME_TYPE_PLUS_VID, /* Name will look like: vlan0005 */
375 VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like: eth1.0005 */
376 VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like: vlan5 */
377 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like: eth0.5 */
378 VLAN_NAME_TYPE_HIGHEST
379};
380
381struct vlan_ioctl_args {
382 int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
383 char device1[24];
384
385 union {
386 char device2[24];
387 int VID;
388 unsigned int skb_priority;
389 unsigned int name_type;
390 unsigned int bind_type;
391 unsigned int flag; /* Matches vlan_dev_info flags */
392 } u;
393
394 short vlan_qos;
395};
396
397#endif /* !(_LINUX_IF_VLAN_H_) */