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1 /*
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 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 
20 #define VLAN_HLEN	4		/* The additional bytes (on top of the Ethernet header)
21 					 * that VLAN requires.
22 					 */
23 #define VLAN_ETH_ALEN	6		/* Octets in one ethernet addr	 */
24 #define VLAN_ETH_HLEN	18		/* Total octets in header.	 */
25 #define VLAN_ETH_ZLEN	64		/* Min. octets in frame sans FCS */
26 
27 /*
28  * According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
29  */
30 #define VLAN_ETH_DATA_LEN	1500	/* Max. octets in payload	 */
31 #define VLAN_ETH_FRAME_LEN	1518	/* Max. octets in frame sans FCS */
32 
33 /*
34  * 	struct vlan_hdr - vlan header
35  * 	@h_vlan_TCI: priority and VLAN ID
36  *	@h_vlan_encapsulated_proto: packet type ID or len
37  */
38 struct vlan_hdr {
39 	__be16	h_vlan_TCI;
40 	__be16	h_vlan_encapsulated_proto;
41 };
42 
43 /**
44  *	struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
45  *	@h_dest: destination ethernet address
46  *	@h_source: source ethernet address
47  *	@h_vlan_proto: ethernet protocol (always 0x8100)
48  *	@h_vlan_TCI: priority and VLAN ID
49  *	@h_vlan_encapsulated_proto: packet type ID or len
50  */
51 struct vlan_ethhdr {
52 	unsigned char	h_dest[ETH_ALEN];
53 	unsigned char	h_source[ETH_ALEN];
54 	__be16		h_vlan_proto;
55 	__be16		h_vlan_TCI;
56 	__be16		h_vlan_encapsulated_proto;
57 };
58 
59 #include <linux/skbuff.h>
60 
vlan_eth_hdr(const struct sk_buff * skb)61 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
62 {
63 	return (struct vlan_ethhdr *)skb_mac_header(skb);
64 }
65 
66 #define VLAN_PRIO_MASK		0xe000 /* Priority Code Point */
67 #define VLAN_PRIO_SHIFT		13
68 #define VLAN_CFI_MASK		0x1000 /* Canonical Format Indicator */
69 #define VLAN_TAG_PRESENT	VLAN_CFI_MASK
70 #define VLAN_VID_MASK		0x0fff /* VLAN Identifier */
71 
72 /* found in socket.c */
73 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
74 
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.
78  */
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)
82 
83 struct vlan_group {
84 	struct net_device	*real_dev; /* The ethernet(like) device
85 					    * the vlan is attached to.
86 					    */
87 	unsigned int		nr_vlans;
88 	int			killall;
89 	struct hlist_node	hlist;	/* linked list */
90 	struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
91 	struct rcu_head		rcu;
92 };
93 
vlan_group_get_device(struct vlan_group * vg,u16 vlan_id)94 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
95 						       u16 vlan_id)
96 {
97 	struct net_device **array;
98 	array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
99 	return array ? array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] : NULL;
100 }
101 
vlan_group_set_device(struct vlan_group * vg,u16 vlan_id,struct net_device * dev)102 static inline void vlan_group_set_device(struct vlan_group *vg,
103 					 u16 vlan_id,
104 					 struct net_device *dev)
105 {
106 	struct net_device **array;
107 	if (!vg)
108 		return;
109 	array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
110 	array[vlan_id % VLAN_GROUP_ARRAY_PART_LEN] = dev;
111 }
112 
113 #define vlan_tx_tag_present(__skb)	((__skb)->vlan_tci & VLAN_TAG_PRESENT)
114 #define vlan_tx_tag_get(__skb)		((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
115 
116 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
117 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
118 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
119 
120 extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
121 			     u16 vlan_tci, int polling);
122 extern int vlan_hwaccel_do_receive(struct sk_buff *skb);
123 extern gro_result_t
124 vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
125 		 unsigned int vlan_tci, struct sk_buff *skb);
126 extern gro_result_t
127 vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
128 	       unsigned int vlan_tci);
129 
130 #else
vlan_dev_real_dev(const struct net_device * dev)131 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
132 {
133 	BUG();
134 	return NULL;
135 }
136 
vlan_dev_vlan_id(const struct net_device * dev)137 static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
138 {
139 	BUG();
140 	return 0;
141 }
142 
__vlan_hwaccel_rx(struct sk_buff * skb,struct vlan_group * grp,u16 vlan_tci,int polling)143 static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
144 				    u16 vlan_tci, int polling)
145 {
146 	BUG();
147 	return NET_XMIT_SUCCESS;
148 }
149 
vlan_hwaccel_do_receive(struct sk_buff * skb)150 static inline int vlan_hwaccel_do_receive(struct sk_buff *skb)
151 {
152 	return 0;
153 }
154 
155 static inline gro_result_t
vlan_gro_receive(struct napi_struct * napi,struct vlan_group * grp,unsigned int vlan_tci,struct sk_buff * skb)156 vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
157 		 unsigned int vlan_tci, struct sk_buff *skb)
158 {
159 	return GRO_DROP;
160 }
161 
162 static inline gro_result_t
vlan_gro_frags(struct napi_struct * napi,struct vlan_group * grp,unsigned int vlan_tci)163 vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
164 	       unsigned int vlan_tci)
165 {
166 	return GRO_DROP;
167 }
168 #endif
169 
170 /**
171  * vlan_hwaccel_rx - netif_rx wrapper for VLAN RX acceleration
172  * @skb: buffer
173  * @grp: vlan group
174  * @vlan_tci: VLAN TCI as received from the card
175  */
vlan_hwaccel_rx(struct sk_buff * skb,struct vlan_group * grp,u16 vlan_tci)176 static inline int vlan_hwaccel_rx(struct sk_buff *skb,
177 				  struct vlan_group *grp,
178 				  u16 vlan_tci)
179 {
180 	return __vlan_hwaccel_rx(skb, grp, vlan_tci, 0);
181 }
182 
183 /**
184  * vlan_hwaccel_receive_skb - netif_receive_skb wrapper for VLAN RX acceleration
185  * @skb: buffer
186  * @grp: vlan group
187  * @vlan_tci: VLAN TCI as received from the card
188  */
vlan_hwaccel_receive_skb(struct sk_buff * skb,struct vlan_group * grp,u16 vlan_tci)189 static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
190 					   struct vlan_group *grp,
191 					   u16 vlan_tci)
192 {
193 	return __vlan_hwaccel_rx(skb, grp, vlan_tci, 1);
194 }
195 
196 /**
197  * __vlan_put_tag - regular VLAN tag inserting
198  * @skb: skbuff to tag
199  * @vlan_tci: VLAN TCI to insert
200  *
201  * Inserts the VLAN tag into @skb as part of the payload
202  * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
203  *
204  * Following the skb_unshare() example, in case of error, the calling function
205  * doesn't have to worry about freeing the original skb.
206  */
__vlan_put_tag(struct sk_buff * skb,u16 vlan_tci)207 static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
208 {
209 	struct vlan_ethhdr *veth;
210 
211 	if (skb_cow_head(skb, VLAN_HLEN) < 0) {
212 		kfree_skb(skb);
213 		return NULL;
214 	}
215 	veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
216 
217 	/* Move the mac addresses to the beginning of the new header. */
218 	memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
219 	skb->mac_header -= VLAN_HLEN;
220 
221 	/* first, the ethernet type */
222 	veth->h_vlan_proto = htons(ETH_P_8021Q);
223 
224 	/* now, the TCI */
225 	veth->h_vlan_TCI = htons(vlan_tci);
226 
227 	skb->protocol = htons(ETH_P_8021Q);
228 
229 	return skb;
230 }
231 
232 /**
233  * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
234  * @skb: skbuff to tag
235  * @vlan_tci: VLAN TCI to insert
236  *
237  * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
238  */
__vlan_hwaccel_put_tag(struct sk_buff * skb,u16 vlan_tci)239 static inline struct sk_buff *__vlan_hwaccel_put_tag(struct sk_buff *skb,
240 						     u16 vlan_tci)
241 {
242 	skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
243 	return skb;
244 }
245 
246 #define HAVE_VLAN_PUT_TAG
247 
248 /**
249  * vlan_put_tag - inserts VLAN tag according to device features
250  * @skb: skbuff to tag
251  * @vlan_tci: VLAN TCI to insert
252  *
253  * Assumes skb->dev is the target that will xmit this frame.
254  * Returns a VLAN tagged skb.
255  */
vlan_put_tag(struct sk_buff * skb,u16 vlan_tci)256 static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb, u16 vlan_tci)
257 {
258 	if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
259 		return __vlan_hwaccel_put_tag(skb, vlan_tci);
260 	} else {
261 		return __vlan_put_tag(skb, vlan_tci);
262 	}
263 }
264 
265 /**
266  * __vlan_get_tag - get the VLAN ID that is part of the payload
267  * @skb: skbuff to query
268  * @vlan_tci: buffer to store vlaue
269  *
270  * Returns error if the skb is not of VLAN type
271  */
__vlan_get_tag(const struct sk_buff * skb,u16 * vlan_tci)272 static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
273 {
274 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
275 
276 	if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
277 		return -EINVAL;
278 	}
279 
280 	*vlan_tci = ntohs(veth->h_vlan_TCI);
281 	return 0;
282 }
283 
284 /**
285  * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
286  * @skb: skbuff to query
287  * @vlan_tci: buffer to store vlaue
288  *
289  * Returns error if @skb->vlan_tci is not set correctly
290  */
__vlan_hwaccel_get_tag(const struct sk_buff * skb,u16 * vlan_tci)291 static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
292 					 u16 *vlan_tci)
293 {
294 	if (vlan_tx_tag_present(skb)) {
295 		*vlan_tci = vlan_tx_tag_get(skb);
296 		return 0;
297 	} else {
298 		*vlan_tci = 0;
299 		return -EINVAL;
300 	}
301 }
302 
303 #define HAVE_VLAN_GET_TAG
304 
305 /**
306  * vlan_get_tag - get the VLAN ID from the skb
307  * @skb: skbuff to query
308  * @vlan_tci: buffer to store vlaue
309  *
310  * Returns error if the skb is not VLAN tagged
311  */
vlan_get_tag(const struct sk_buff * skb,u16 * vlan_tci)312 static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
313 {
314 	if (skb->dev->features & NETIF_F_HW_VLAN_TX) {
315 		return __vlan_hwaccel_get_tag(skb, vlan_tci);
316 	} else {
317 		return __vlan_get_tag(skb, vlan_tci);
318 	}
319 }
320 
321 #endif /* __KERNEL__ */
322 
323 /* VLAN IOCTLs are found in sockios.h */
324 
325 /* Passed in vlan_ioctl_args structure to determine behaviour. */
326 enum vlan_ioctl_cmds {
327 	ADD_VLAN_CMD,
328 	DEL_VLAN_CMD,
329 	SET_VLAN_INGRESS_PRIORITY_CMD,
330 	SET_VLAN_EGRESS_PRIORITY_CMD,
331 	GET_VLAN_INGRESS_PRIORITY_CMD,
332 	GET_VLAN_EGRESS_PRIORITY_CMD,
333 	SET_VLAN_NAME_TYPE_CMD,
334 	SET_VLAN_FLAG_CMD,
335 	GET_VLAN_REALDEV_NAME_CMD, /* If this works, you know it's a VLAN device, btw */
336 	GET_VLAN_VID_CMD /* Get the VID of this VLAN (specified by name) */
337 };
338 
339 enum vlan_flags {
340 	VLAN_FLAG_REORDER_HDR	= 0x1,
341 	VLAN_FLAG_GVRP		= 0x2,
342 	VLAN_FLAG_LOOSE_BINDING	= 0x4,
343 };
344 
345 enum vlan_name_types {
346 	VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
347 	VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
348 	VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
349 	VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
350 	VLAN_NAME_TYPE_HIGHEST
351 };
352 
353 struct vlan_ioctl_args {
354 	int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
355 	char device1[24];
356 
357         union {
358 		char device2[24];
359 		int VID;
360 		unsigned int skb_priority;
361 		unsigned int name_type;
362 		unsigned int bind_type;
363 		unsigned int flag; /* Matches vlan_dev_info flags */
364         } u;
365 
366 	short vlan_qos;
367 };
368 
369 #endif /* !(_LINUX_IF_VLAN_H_) */
370