if_vlan_var.h revision 142069 
1/*-
2 * Copyright 1998 Massachusetts Institute of Technology
3 *
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission.  M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose.  It is provided "as is" without express or implied
14 * warranty.
15 *
16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: head/sys/net/if_vlan_var.h 142069 2005-02-18 22:31:19Z ru $
30 */
31
32#ifndef _NET_IF_VLAN_VAR_H_
33#define	_NET_IF_VLAN_VAR_H_	1
34
35struct	ether_vlan_header {
36	u_char	evl_dhost[ETHER_ADDR_LEN];
37	u_char	evl_shost[ETHER_ADDR_LEN];
38	u_int16_t evl_encap_proto;
39	u_int16_t evl_tag;
40	u_int16_t evl_proto;
41};
42
43#define EVL_VLID_MASK	0x0FFF
44#define	EVL_VLANOFTAG(tag) ((tag) & EVL_VLID_MASK)
45#define	EVL_PRIOFTAG(tag) (((tag) >> 13) & 7)
46
47/* sysctl(3) tags, for compatibility purposes */
48#define	VLANCTL_PROTO	1
49#define	VLANCTL_MAX	2
50
51/*
52 * Configuration structure for SIOCSETVLAN and SIOCGETVLAN ioctls.
53 */
54struct	vlanreq {
55	char	vlr_parent[IFNAMSIZ];
56	u_short	vlr_tag;
57};
58#define	SIOCSETVLAN	SIOCSIFGENERIC
59#define	SIOCGETVLAN	SIOCGIFGENERIC
60
61#ifdef _KERNEL
62/*
63 * Drivers that are capable of adding and removing the VLAN header
64 * in hardware indicate they support this by marking IFCAP_VLAN_HWTAGGING
65 * in if_capabilities.  Drivers for hardware that is capable
66 * of handling larger MTU's that may include a software-appended
67 * VLAN header w/o lowering the normal MTU should mark IFCAP_VLAN_MTU
68 * in if_capabilities; this notifies the VLAN code it can leave the
69 * MTU on the vlan interface at the normal setting.
70 */
71
72/*
73 * Drivers that support hardware VLAN tagging pass a packet's tag
74 * up through the stack by appending a packet tag with this value.
75 * Output is handled likewise, the driver must locate the packet
76 * tag to extract the VLAN tag.  The following macros are used to
77 * do this work.  On input, do:
78 *
79 *	VLAN_INPUT_TAG(ifp, m, tag,);
80 *
81 * to mark the packet m with the specified VLAN tag.  The last
82 * parameter provides code to execute in case of an error.  On
83 * output the driver should check mbuf to see if a VLAN tag is
84 * present and only then check for a tag; this is done with:
85 *
86 *	struct m_tag *mtag;
87 *	mtag = VLAN_OUTPUT_TAG(ifp, m);
88 *	if (mtag != NULL) {
89 *		... = VLAN_TAG_VALUE(mtag);
90 *		... pass tag to hardware ...
91 *	}
92 *
93 * Note that a driver must indicate it supports hardware VLAN
94 * tagging by marking IFCAP_VLAN_HWTAGGING in if_capabilities.
95 */
96#define	MTAG_VLAN	1035328035
97#define	MTAG_VLAN_TAG	0		/* tag of VLAN interface */
98
99#define	VLAN_INPUT_TAG(_ifp, _m, _t, _errcase) do {		\
100	struct m_tag *mtag;					\
101	mtag = m_tag_alloc(MTAG_VLAN, MTAG_VLAN_TAG,		\
102			   sizeof (u_int), M_NOWAIT);		\
103	if (mtag == NULL) {					\
104		(_ifp)->if_ierrors++;				\
105		m_freem(_m);					\
106		_errcase;					\
107	}							\
108	*(u_int *)(mtag+1) = (_t);				\
109	m_tag_prepend((_m), mtag);				\
110	(_m)->m_flags |= M_VLANTAG;				\
111} while (0)
112
113#define	VLAN_OUTPUT_TAG(_ifp, _m)				\
114	((_m)->m_flags & M_VLANTAG ?				\
115		m_tag_locate((_m), MTAG_VLAN, MTAG_VLAN_TAG, NULL) : NULL)
116#define	VLAN_TAG_VALUE(_mt)	(*(u_int *)((_mt)+1))
117#endif /* _KERNEL */
118
119#endif /* _NET_IF_VLAN_VAR_H_ */
120