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
18/* externally defined structs */
19struct vlan_group;
20struct net_device;
21struct sk_buff;
22struct packet_type;
23struct vlan_collection;
24struct vlan_dev_info;
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	*/
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) */
48};
49
50struct vlan_hdr {
51   unsigned short       h_vlan_TCI;                /* Encapsulates priority and VLAN ID */
52   unsigned short       h_vlan_encapsulated_proto; /* packet type ID field (or len) */
53};
54
55#define VLAN_VID_MASK	0xfff
56
57/* found in af_inet.c */
58extern int (*vlan_ioctl_hook)(unsigned long arg);
59
60#define VLAN_NAME "vlan"
61
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.
65 */
66#define VLAN_GROUP_ARRAY_LEN 4096
67
68struct vlan_group {
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];
71
72	struct vlan_group *next; /* the next in the list */
73};
74
75struct 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)
80				  */
81	struct vlan_priority_tci_mapping *next;
82};
83
84/* Holds information that makes sense if this device is a VLAN device. */
85struct vlan_dev_info {
86	/** This will be the mapping that correlates skb->priority to
87	 * 3 bits of VLAN QOS tags...
88	 */
89	unsigned long ingress_priority_map[8];
90	struct vlan_priority_tci_mapping *egress_priority_map[16]; /* hash table */
91
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
99                                        *   802.1Q
100                                        */
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...
105                                           */
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...) */
113};
114
115#define VLAN_DEV_INFO(x) ((struct vlan_dev_info *)(x->priv))
116
117/* inline functions */
118
119static inline struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
120{
121	return &(VLAN_DEV_INFO(dev)->dev_stats);
122}
123
124static inline __u32 vlan_get_ingress_priority(struct net_device *dev,
125					      unsigned short vlan_tag)
126{
127	struct vlan_dev_info *vip = VLAN_DEV_INFO(dev);
128
129	return vip->ingress_priority_map[(vlan_tag >> 13) & 0x7];
130}
131
132/* VLAN tx hw acceleration helpers. */
133struct vlan_skb_tx_cookie {
134	u32	magic;
135	u32	vlan_tag;
136};
137
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)
143
144/* VLAN rx hw acceleration helper.  This acts like netif_{rx,receive_skb}(). */
145static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
146				    struct vlan_group *grp,
147				    unsigned short vlan_tag, int polling)
148{
149	struct net_device_stats *stats;
150
151	skb->dev = grp->vlan_devices[vlan_tag & VLAN_VID_MASK];
152	if (skb->dev == NULL) {
153		kfree_skb(skb);
154
155		/* Not NET_RX_DROP, this is not being dropped
156		 * due to congestion.
157		 */
158		return 0;
159	}
160
161	skb->dev->last_rx = jiffies;
162
163	stats = vlan_dev_get_stats(skb->dev);
164	stats->rx_packets++;
165	stats->rx_bytes += skb->len;
166
167	skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tag);
168	switch (skb->pkt_type) {
169	case PACKET_BROADCAST:
170		break;
171
172	case PACKET_MULTICAST:
173		stats->multicast++;
174		break;
175
176	case PACKET_OTHERHOST:
177		/* Our lower layer thinks this is not local, let's make sure.
178		 * This allows the VLAN to have a different MAC than the underlying
179		 * device, and still route correctly.
180		 */
181		if (!memcmp(skb->mac.ethernet->h_dest, skb->dev->dev_addr, ETH_ALEN))
182			skb->pkt_type = PACKET_HOST;
183		break;
184	};
185
186	return (polling ? netif_receive_skb(skb) : netif_rx(skb));
187}
188
189static inline int vlan_hwaccel_rx(struct sk_buff *skb,
190				  struct vlan_group *grp,
191				  unsigned short vlan_tag)
192{
193	return __vlan_hwaccel_rx(skb, grp, vlan_tag, 0);
194}
195
196static inline int vlan_hwaccel_receive_skb(struct sk_buff *skb,
197					   struct vlan_group *grp,
198					   unsigned short vlan_tag)
199{
200	return __vlan_hwaccel_rx(skb, grp, vlan_tag, 1);
201}
202#endif /* __KERNEL__ */
203
204/* VLAN IOCTLs are found in sockios.h */
205
206/* Passed in vlan_ioctl_args structure to determine behaviour. */
207enum vlan_ioctl_cmds {
208	ADD_VLAN_CMD,
209	DEL_VLAN_CMD,
210	SET_VLAN_INGRESS_PRIORITY_CMD,
211	SET_VLAN_EGRESS_PRIORITY_CMD,
212	GET_VLAN_INGRESS_PRIORITY_CMD,
213	GET_VLAN_EGRESS_PRIORITY_CMD,
214	SET_VLAN_NAME_TYPE_CMD,
215	SET_VLAN_FLAG_CMD
216};
217
218enum vlan_name_types {
219	VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
220	VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
221	VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
222	VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
223	VLAN_NAME_TYPE_HIGHEST
224};
225
226struct vlan_ioctl_args {
227	int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
228	char device1[24];
229
230        union {
231		char device2[24];
232		int VID;
233		unsigned int skb_priority;
234		unsigned int name_type;
235		unsigned int bind_type;
236		unsigned int flag; /* Matches vlan_dev_info flags */
237        } u;
238
239	short vlan_qos;
240};
241
242#endif /* !(_LINUX_IF_VLAN_H_) */
243