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 */
22 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) */
50 #include <linux/skbuff.h>
52 static inline struct vlan_ethhdr
*vlan_eth_hdr(const struct sk_buff
*skb
)
54 return (struct vlan_ethhdr
*)skb
->mac
.raw
;
58 unsigned short h_vlan_TCI
; /* Encapsulates priority and VLAN ID */
59 unsigned short h_vlan_encapsulated_proto
; /* packet type ID field (or len) */
62 #define VLAN_VID_MASK 0xfff
64 /* found in socket.c */
65 extern void vlan_ioctl_set(int (*hook
)(void __user
*));
67 #define VLAN_NAME "vlan"
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.
73 #define VLAN_GROUP_ARRAY_LEN 4096
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
];
82 struct 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)
88 struct vlan_priority_tci_mapping
*next
;
91 /* Holds information that makes sense if this device is a VLAN device. */
92 struct vlan_dev_info
{
93 /** This will be the mapping that correlates skb->priority to
94 * 3 bits of VLAN QOS tags...
96 unsigned long ingress_priority_map
[8];
97 struct vlan_priority_tci_mapping
*egress_priority_map
[16]; /* hash table */
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
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...
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...) */
122 #define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
124 /* inline functions */
126 static inline struct net_device_stats
*vlan_dev_get_stats(struct net_device
*dev
)
128 return &(VLAN_DEV_INFO(dev
)->dev_stats
);
131 static inline __u32
vlan_get_ingress_priority(struct net_device
*dev
,
132 unsigned short vlan_tag
)
134 struct vlan_dev_info
*vip
= VLAN_DEV_INFO(dev
);
136 return vip
->ingress_priority_map
[(vlan_tag
>> 13) & 0x7];
139 /* VLAN tx hw acceleration helpers. */
140 struct vlan_skb_tx_cookie
{
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)
151 /* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
152 static inline int __vlan_hwaccel_rx(struct sk_buff
*skb
,
153 struct vlan_group
*grp
,
154 unsigned short vlan_tag
, int polling
)
156 struct net_device_stats
*stats
;
158 skb
->real_dev
= skb
->dev
;
159 skb
->dev
= grp
->vlan_devices
[vlan_tag
& VLAN_VID_MASK
];
160 if (skb
->dev
== NULL
) {
161 dev_kfree_skb_any(skb
);
163 /* Not NET_RX_DROP, this is not being dropped
169 skb
->dev
->last_rx
= jiffies
;
171 stats
= vlan_dev_get_stats(skb
->dev
);
173 stats
->rx_bytes
+= skb
->len
;
175 skb
->priority
= vlan_get_ingress_priority(skb
->dev
, vlan_tag
);
176 switch (skb
->pkt_type
) {
177 case PACKET_BROADCAST
:
180 case PACKET_MULTICAST
:
184 case PACKET_OTHERHOST
:
185 /* Our lower layer thinks this is not local, let's make sure.
186 * This allows the VLAN to have a different MAC than the underlying
187 * device, and still route correctly.
189 if (!memcmp(eth_hdr(skb
)->h_dest
, skb
->dev
->dev_addr
, ETH_ALEN
))
190 skb
->pkt_type
= PACKET_HOST
;
194 return (polling
? netif_receive_skb(skb
) : netif_rx(skb
));
197 static inline int vlan_hwaccel_rx(struct sk_buff
*skb
,
198 struct vlan_group
*grp
,
199 unsigned short vlan_tag
)
201 return __vlan_hwaccel_rx(skb
, grp
, vlan_tag
, 0);
204 static inline int vlan_hwaccel_receive_skb(struct sk_buff
*skb
,
205 struct vlan_group
*grp
,
206 unsigned short vlan_tag
)
208 return __vlan_hwaccel_rx(skb
, grp
, vlan_tag
, 1);
212 * __vlan_put_tag - regular VLAN tag inserting
213 * @skb: skbuff to tag
214 * @tag: VLAN tag to insert
216 * Inserts the VLAN tag into @skb as part of the payload
217 * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
219 * Following the skb_unshare() example, in case of error, the calling function
220 * doesn't have to worry about freeing the original skb.
222 static inline struct sk_buff
*__vlan_put_tag(struct sk_buff
*skb
, unsigned short tag
)
224 struct vlan_ethhdr
*veth
;
226 if (skb_headroom(skb
) < VLAN_HLEN
) {
227 struct sk_buff
*sk_tmp
= skb
;
228 skb
= skb_realloc_headroom(sk_tmp
, VLAN_HLEN
);
231 printk(KERN_ERR
"vlan: failed to realloc headroom\n");
235 skb
= skb_unshare(skb
, GFP_ATOMIC
);
237 printk(KERN_ERR
"vlan: failed to unshare skbuff\n");
242 veth
= (struct vlan_ethhdr
*)skb_push(skb
, VLAN_HLEN
);
244 /* Move the mac addresses to the beginning of the new header. */
245 memmove(skb
->data
, skb
->data
+ VLAN_HLEN
, 2 * VLAN_ETH_ALEN
);
247 /* first, the ethernet type */
248 veth
->h_vlan_proto
= __constant_htons(ETH_P_8021Q
);
251 veth
->h_vlan_TCI
= htons(tag
);
253 skb
->protocol
= __constant_htons(ETH_P_8021Q
);
254 skb
->mac
.raw
-= VLAN_HLEN
;
255 skb
->nh
.raw
-= VLAN_HLEN
;
261 * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
262 * @skb: skbuff to tag
263 * @tag: VLAN tag to insert
265 * Puts the VLAN tag in @skb->cb[] and lets the device do the rest
267 static inline struct sk_buff
*__vlan_hwaccel_put_tag(struct sk_buff
*skb
, unsigned short tag
)
269 struct vlan_skb_tx_cookie
*cookie
;
271 cookie
= VLAN_TX_SKB_CB(skb
);
272 cookie
->magic
= VLAN_TX_COOKIE_MAGIC
;
273 cookie
->vlan_tag
= tag
;
278 #define HAVE_VLAN_PUT_TAG
281 * vlan_put_tag - inserts VLAN tag according to device features
282 * @skb: skbuff to tag
283 * @tag: VLAN tag to insert
285 * Assumes skb->dev is the target that will xmit this frame.
286 * Returns a VLAN tagged skb.
288 static inline struct sk_buff
*vlan_put_tag(struct sk_buff
*skb
, unsigned short tag
)
290 if (skb
->dev
->features
& NETIF_F_HW_VLAN_TX
) {
291 return __vlan_hwaccel_put_tag(skb
, tag
);
293 return __vlan_put_tag(skb
, tag
);
298 * __vlan_get_tag - get the VLAN ID that is part of the payload
299 * @skb: skbuff to query
300 * @tag: buffer to store vlaue
302 * Returns error if the skb is not of VLAN type
304 static inline int __vlan_get_tag(struct sk_buff
*skb
, unsigned short *tag
)
306 struct vlan_ethhdr
*veth
= (struct vlan_ethhdr
*)skb
->data
;
308 if (veth
->h_vlan_proto
!= __constant_htons(ETH_P_8021Q
)) {
312 *tag
= ntohs(veth
->h_vlan_TCI
);
318 * __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
319 * @skb: skbuff to query
320 * @tag: buffer to store vlaue
322 * Returns error if @skb->cb[] is not set correctly
324 static inline int __vlan_hwaccel_get_tag(struct sk_buff
*skb
, unsigned short *tag
)
326 struct vlan_skb_tx_cookie
*cookie
;
328 cookie
= VLAN_TX_SKB_CB(skb
);
329 if (cookie
->magic
== VLAN_TX_COOKIE_MAGIC
) {
330 *tag
= cookie
->vlan_tag
;
338 #define HAVE_VLAN_GET_TAG
341 * vlan_get_tag - get the VLAN ID from the skb
342 * @skb: skbuff to query
343 * @tag: buffer to store vlaue
345 * Returns error if the skb is not VLAN tagged
347 static inline int vlan_get_tag(struct sk_buff
*skb
, unsigned short *tag
)
349 if (skb
->dev
->features
& NETIF_F_HW_VLAN_TX
) {
350 return __vlan_hwaccel_get_tag(skb
, tag
);
352 return __vlan_get_tag(skb
, tag
);
356 #endif /* __KERNEL__ */
358 /* VLAN IOCTLs are found in sockios.h */
360 /* Passed in vlan_ioctl_args structure to determine behaviour. */
361 enum vlan_ioctl_cmds
{
364 SET_VLAN_INGRESS_PRIORITY_CMD
,
365 SET_VLAN_EGRESS_PRIORITY_CMD
,
366 GET_VLAN_INGRESS_PRIORITY_CMD
,
367 GET_VLAN_EGRESS_PRIORITY_CMD
,
368 SET_VLAN_NAME_TYPE_CMD
,
370 GET_VLAN_REALDEV_NAME_CMD
, /* If this works, you know it's a VLAN device, btw */
371 GET_VLAN_VID_CMD
/* Get the VID of this VLAN (specified by name) */
374 enum vlan_name_types
{
375 VLAN_NAME_TYPE_PLUS_VID
, /* Name will look like: vlan0005 */
376 VLAN_NAME_TYPE_RAW_PLUS_VID
, /* name will look like: eth1.0005 */
377 VLAN_NAME_TYPE_PLUS_VID_NO_PAD
, /* Name will look like: vlan5 */
378 VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD
, /* Name will look like: eth0.5 */
379 VLAN_NAME_TYPE_HIGHEST
382 struct vlan_ioctl_args
{
383 int cmd
; /* Should be one of the vlan_ioctl_cmds enum above. */
389 unsigned int skb_priority
;
390 unsigned int name_type
;
391 unsigned int bind_type
;
392 unsigned int flag
; /* Matches vlan_dev_info flags */
398 #endif /* !(_LINUX_IF_VLAN_H_) */