aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/if_vlan.h
blob: c7912876a2102c02e0dac48108b5ffa22230cc9e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
/*
 * VLAN		An implementation of 802.1Q VLAN tagging.
 *
 * Authors:	Ben Greear <greearb@candelatech.com>
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */

#ifndef _LINUX_IF_VLAN_H_
#define _LINUX_IF_VLAN_H_

#ifdef __KERNEL__

/* externally defined structs */
struct vlan_group;
struct net_device;
struct packet_type;
struct vlan_collection;
struct vlan_dev_info;
struct hlist_node;

#include <linux/netdevice.h>
#include <linux/etherdevice.h>

#define VLAN_HLEN	4		/* The additional bytes (on top of the Ethernet header)
					 * that VLAN requires.
					 */
#define VLAN_ETH_ALEN	6		/* Octets in one ethernet addr	 */
#define VLAN_ETH_HLEN	18		/* Total octets in header.	 */
#define VLAN_ETH_ZLEN	64		/* Min. octets in frame sans FCS */

/*
 * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
 */
#define VLAN_ETH_DATA_LEN	1500	/* Max. octets in payload	 */
#define VLAN_ETH_FRAME_LEN	1518	/* Max. octets in frame sans FCS */

struct vlan_ethhdr {
   unsigned char	h_dest[ETH_ALEN];	   /* destination eth addr	*/
   unsigned char	h_source[ETH_ALEN];	   /* source ether addr	*/
   __be16               h_vlan_proto;              /* Should always be 0x8100 */
   __be16               h_vlan_TCI;                /* Encapsulates priority and VLAN ID */
   __be16		h_vlan_encapsulated_proto; /* packet type ID field (or len) */
};

#include <linux/skbuff.h>

static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
{
	return (struct vlan_ethhdr *)skb_mac_header(skb);
}

struct vlan_hdr {
   __be16               h_vlan_TCI;                /* Encapsulates priority and VLAN ID */
   __be16               h_vlan_encapsulated_proto; /* packet type ID field (or len) */
};

#define VLAN_VID_MASK	0xfff

/* found in socket.c */
extern void vlan_ioctl_set(int (*hook)(void __user *));

#define VLAN_NAME "vlan"

/* if this changes, algorithm will have to be reworked because this
 * depends on completely exhausting the VLAN identifier space.  Thus
 * it gives constant time look-up, but in many cases it wastes memory.
 */
#define VLAN_GROUP_ARRAY_LEN          4096
#define VLAN_GROUP_ARRAY_SPLIT_PARTS  8
#define VLAN_GROUP_ARRAY_PART_LEN     (VLAN_GROUP_ARRAY_LEN/VLAN_GROUP_ARRAY_SPLIT_PARTS)

struct vlan_group {
	int real_dev_ifindex; /* The ifindex of the ethernet(like) device the vlan is attached to. */
	struct hlist_node	hlist;	/* linked list */
	struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
	struct rcu_head		rcu;
};

static inline struct net_device *vlan_group_get_device(struct vlan_group *vg, int vlan_id)
{
	struct net_device **array;
	array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
	return array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN];
}

static inline void vlan_group_set_device(struct vlan_group *vg, int vlan_id,
					 struct net_device *dev)
{
	struct net_device **array;
	if (!vg)
		return;
	array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
	array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
}

struct vlan_priority_tci_mapping {
	u32 priority;
	unsigned short vlan_qos; /* This should be shifted when first set, so we only do it
				  * at provisioning time.
				  * ((skb->priority << 13) & 0xE000)
				  */
	struct vlan_priority_tci_mapping *next;
};

/* Holds information that makes sense if this device is a VLAN device. */
struct vlan_dev_info {
	/** This will be the mapping that correlates skb->priority to
	 * 3 bits of VLAN QOS tags...
	 */
	unsigned int nr_ingress_mappings;
	u32 ingress_priority_map[8];

	unsigned int nr_egress_mappings;
	struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */

	unsigned short vlan_id;        /*  The VLAN Identifier for this interface. */
	unsigned short flags;          /* (1 << 0) re_order_header   This option will cause the
                                        *   VLAN code to move around the ethernet header on
                                        *   ingress to make the skb look **exactly** like it
                                        *   came in from an ethernet port.  This destroys some of
                                        *   the VLAN information in the skb, but it fixes programs
                                        *   like DHCP that use packet-filtering and don't understand
                                        *   802.1Q
                                        */
	struct dev_mc_list *old_mc_list;  /* old multi-cast list for the VLAN interface..
                                           * we save this so we can tell what changes were
                                           * made, in order to feed the right changes down
                                           * to the real hardware...
                                           */
	int old_allmulti;               /* similar to above. */
	int old_promiscuity;            /* similar to above. */
	struct net_device *real_dev;    /* the underlying device/interface */
	struct proc_dir_entry *dent;    /* Holds the proc data */
	unsigned long cnt_inc_headroom_on_tx; /* How many times did we have to grow the skb on TX. */
	unsigned long cnt_encap_on_xmit;      /* How many times did we have to encapsulate the skb on TX. */
	struct net_device_stats dev_stats; /* Device stats (rx-bytes, tx-pkts, etc...) */
};

#define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))

/* inline functions */

static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
{
	return &(VLAN_DEV_INFO(dev)->dev_stats);
}

static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
					      unsigned short vlan_tag)
{
	struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);

	return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
}

/* VLAN tx hw acceleration helpers. */
struct vlan_skb_tx_cookie {
	u32	magic;
	u32	vlan_tag;
};

#define VLAN_TX_COOKIE_MAGIC	0x564c414e	/* "VLAN" in ascii. */
#define VLAN_TX_SKB_CB(__skb)	((struct vlan_skb_tx_cookie *)&((__skb)->cb[0]))
#define vlan_tx_tag_present(__skb) \
	(VLAN_TX_SKB_CB(__skb)->magic == VLAN_TX_COOKIE_MAGIC)
#define vlan_tx_tag_get(__skb)	(VLAN_TX_SKB_CB(__skb)->vlan_tag)

/* VLAN rx hw acceleration helper.  This acts like netif_{rx,receive_skb}(). */
static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
				    struct vlan_group *grp,
				    unsigned short vlan_tag, int polling)
{
	struct net_device_stats *stats;

	if (skb_bond_should_drop(skb)) {
		dev_kfree_skb_any(skb);
		return NET_RX_DROP;
	}

	skb->dev = vlan_group_get_device(grp, vlan_tag & VLAN_VID_MASK);
	if (skb->dev == NULL) {
		dev_kfree_skb_any(skb);

		/* Not NET_RX_DROP, this is not being dropped
		 * due to congestion.
		 */
		return 0;
	}

	skb->dev->last_rx = jiffies;

	stats = vlan_dev_get_stats(skb->dev);
	stats->rx_packets++;
	stats->rx_bytes += skb->len;

	skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
	switch (skb->pkt_type) {
	case PACKET_BROADCAST:
		break;

	case PACKET_MULTICAST:
		stats->multicast++;
		break;

	case PACKET_OTHERHOST:
		/* Our lower layer thinks this is not local, let's make sure.
		 * This allows the VLAN to have a different MAC than the underlying
		 * device, and still route correctly.
		 */
		if (!compare_ether_addr(eth_hdr(skb)->h_dest,
				       	skb->dev->dev_addr))
			skb->pkt_type = PACKET_HOST;
		break;
	};

	return (polling ? netif_receive_skb(skb) : netif_rx(skb));
}

static inline int vlan_hwaccel_rx(struct sk_buff *skb,
				  struct vlan_group *grp,
				  unsigned short vlan_tag)
{
	return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
}

static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
					   struct vlan_group *grp,
					   unsigned short vlan_tag)
{
	return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
}

/**
 * __vlan_put_tag - regular VLAN tag inserting
 * @skb: skbuff to tag
 * @tag: VLAN tag to insert
 *
 * Inserts the VLAN tag into @skb as part of the payload
 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
 * 
 * Following the skb_unshare() example, in case of error, the calling function
 * doesn't have to worry about freeing the original skb.
 */
static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, unsigned short tag)
{
	struct vlan_ethhdr *veth;

	if (skb_headroom(skb) < VLAN_HLEN) {
		struct sk_buff *sk_tmp = skb;
		skb = skb_realloc_headroom(sk_tmp, VLAN_HLEN);
		kfree_skb(sk_tmp);
		if (!skb) {
			printk(KERN_ERR "vlan: failed to realloc headroom\n");
			return NULL;
		}
	} else {
		skb = skb_unshare(skb, GFP_ATOMIC);
		if (!skb) {
			printk(KERN_ERR "vlan: failed to unshare skbuff\n");
			return NULL;
		}
	}

	veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);

	/* Move the mac addresses to the beginning of the new header. */
	memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);

	/* first, the ethernet type */
	veth->h_vlan_proto = __constant_htons(ETH_P_8021Q);

	/* now, the tag */
	veth->h_vlan_TCI = htons(tag);

	skb->protocol = __constant_htons(ETH_P_8021Q);
	skb->mac_header -= VLAN_HLEN;
	skb->network_header -= VLAN_HLEN;

	return skb;
}

/**
 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
 * @skb: skbuff to tag
 * @tag: VLAN tag to insert
 *
 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
 */
static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb, unsigned short tag)
{
	struct vlan_skb_tx_cookie *cookie;

	cookie = VLAN_TX_SKB_CB(skb);
	cookie->magic = VLAN_TX_COOKIE_MAGIC;
	cookie->vlan_tag = tag;

	return skb;
}

#define HAVE_VLAN_PUT_TAG

/**
 * vlan_put_tag - inserts VLAN tag according to device features
 * @skb: skbuff to tag
 * @tag: VLAN tag to insert
 *
 * Assumes skb->dev is the target that will xmit this frame.
 * Returns a VLAN tagged skb.
 */
static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, unsigned short tag)
{
	if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
		return __vlan_hwaccel_put_tag(skb, tag);
	} else {
		return __vlan_put_tag(skb, tag);
	}
}

/**
 * __vlan_get_tag - get the VLAN ID that is part of the payload
 * @skb: skbuff to query
 * @tag: buffer to store vlaue
 * 
 * Returns error if the skb is not of VLAN type
 */
static inline int __vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
{
	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;

	if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
		return -EINVAL;
	}

	*tag = ntohs(veth->h_vlan_TCI);

	return 0;
}

/**
 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
 * @skb: skbuff to query
 * @tag: buffer to store vlaue
 * 
 * Returns error if @skb->cb[] is not set correctly
 */
static inline int __vlan_hwaccel_get_tag(struct sk_buff *skb, unsigned short *tag)
{
	struct vlan_skb_tx_cookie *cookie;

	cookie = VLAN_TX_SKB_CB(skb);
	if (cookie->magic == VLAN_TX_COOKIE_MAGIC) {
		*tag = cookie->vlan_tag;
		return 0;
	} else {
		*tag = 0;
		return -EINVAL;
	}
}

#define HAVE_VLAN_GET_TAG

/**
 * vlan_get_tag - get the VLAN ID from the skb
 * @skb: skbuff to query
 * @tag: buffer to store vlaue
 * 
 * Returns error if the skb is not VLAN tagged
 */
static inline int vlan_get_tag(struct sk_buff *skb, unsigned short *tag)
{
	if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
		return __vlan_hwaccel_get_tag(skb, tag);
	} else {
		return __vlan_get_tag(skb, tag);
	}
}

#endif /* __KERNEL__ */

/* VLAN IOCTLs are found in sockios.h */

/* Passed in vlan_ioctl_args structure to determine behaviour. */
enum vlan_ioctl_cmds {
	ADD_VLAN_CMD,
	DEL_VLAN_CMD,
	SET_VLAN_INGRESS_PRIORITY_CMD,
	SET_VLAN_EGRESS_PRIORITY_CMD,
	GET_VLAN_INGRESS_PRIORITY_CMD,
	GET_VLAN_EGRESS_PRIORITY_CMD,
	SET_VLAN_NAME_TYPE_CMD,
	SET_VLAN_FLAG_CMD,
	GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
	GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
};

enum vlan_flags {
	VLAN_FLAG_REORDER_HDR	= 0x1,
};

enum vlan_name_types {
	VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
	VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
	VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
	VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
	VLAN_NAME_TYPE_HIGHEST
};

struct vlan_ioctl_args {
	int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
	char device1[24];

        union {
		char device2[24];
		int VID;
		unsigned int skb_priority;
		unsigned int name_type;
		unsigned int bind_type;
		unsigned int flag; /* Matches vlan_dev_info flags */
        } u;

	short vlan_qos;   
};

#endif /* !(_LINUX_IF_VLAN_H_) */