if_gre.h revision 125020 
1/*	$NetBSD: if_gre.h,v 1.13 2003/11/10 08:51:52 wiz Exp $ */
2/*	 $FreeBSD: head/sys/net/if_gre.h 125020 2004-01-26 12:21:59Z sobomax $ */
3
4/*
5 * Copyright (c) 1998 The NetBSD Foundation, Inc.
6 * All rights reserved
7 *
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Heiko W.Rupp <hwr@pilhuhn.de>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *        This product includes software developed by the NetBSD
22 *        Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 *    contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40#ifndef _NET_IF_GRE_H
41#define _NET_IF_GRE_H
42
43#include <sys/ioccom.h>
44#ifdef _KERNEL
45#include <sys/queue.h>
46
47struct gre_softc {
48	struct ifnet sc_if;
49	LIST_ENTRY(gre_softc) sc_list;
50	int gre_unit;
51	int gre_flags;
52	struct in_addr g_src;	/* source address of gre packets */
53	struct in_addr g_dst;	/* destination address of gre packets */
54	struct route route;	/* routing entry that determines, where a
55				   encapsulated packet should go */
56	u_char g_proto;		/* protocol of encapsulator */
57
58	const struct encaptab *encap;	/* encapsulation cookie */
59
60	int called;		/* infinite recursion preventer */
61};
62
63
64struct gre_h {
65	u_int16_t flags;	/* GRE flags */
66	u_int16_t ptype;	/* protocol type of payload typically
67				   Ether protocol type*/
68/*
69 *  from here on: fields are optional, presence indicated by flags
70 *
71	u_int_16 checksum	checksum (one-complements of GRE header
72				and payload
73				Present if (ck_pres | rt_pres == 1).
74				Valid if (ck_pres == 1).
75	u_int_16 offset		offset from start of routing filed to
76				first octet of active SRE (see below).
77				Present if (ck_pres | rt_pres == 1).
78				Valid if (rt_pres == 1).
79	u_int_32 key		inserted by encapsulator e.g. for
80				authentication
81				Present if (key_pres ==1 ).
82	u_int_32 seq_num	Sequence number to allow for packet order
83				Present if (seq_pres ==1 ).
84	struct gre_sre[] routing Routing fileds (see below)
85				Present if (rt_pres == 1)
86 */
87} __packed;
88
89struct greip {
90	struct ip gi_i;
91	struct gre_h  gi_g;
92} __packed;
93
94#define gi_pr		gi_i.ip_p
95#define gi_len		gi_i.ip_len
96#define gi_src		gi_i.ip_src
97#define gi_dst		gi_i.ip_dst
98#define gi_ptype	gi_g.ptype
99#define gi_flags	gi_g.flags
100
101#define GRE_CP		0x8000  /* Checksum Present */
102#define GRE_RP		0x4000  /* Routing Present */
103#define GRE_KP		0x2000  /* Key Present */
104#define GRE_SP		0x1000  /* Sequence Present */
105#define GRE_SS		0x0800	/* Strict Source Route */
106
107/*
108 * CISCO uses special type for GRE tunnel created as part of WCCP
109 * connection, while in fact those packets are just IPv4 encapsulated
110 * into GRE.
111 */
112#define WCCP_PROTOCOL_TYPE	0x883E
113
114/*
115 * gre_sre defines a Source route Entry. These are needed if packets
116 * should be routed over more than one tunnel hop by hop
117 */
118struct gre_sre {
119	u_int16_t sre_family;	/* address family */
120	u_char	sre_offset;	/* offset to first octet of active entry */
121	u_char	sre_length;	/* number of octets in the SRE.
122				   sre_lengthl==0 -> last entry. */
123	u_char	*sre_rtinfo;	/* the routing information */
124};
125
126struct greioctl {
127	int unit;
128	struct in_addr addr;
129};
130
131/* for mobile encaps */
132
133struct mobile_h {
134	u_int16_t proto;		/* protocol and S-bit */
135	u_int16_t hcrc;			/* header checksum */
136	u_int32_t odst;			/* original destination address */
137	u_int32_t osrc;			/* original source addr, if S-bit set */
138} __packed;
139
140struct mobip_h {
141	struct ip	mi;
142	struct mobile_h	mh;
143} __packed;
144
145
146#define MOB_H_SIZ_S		(sizeof(struct mobile_h) - sizeof(u_int32_t))
147#define MOB_H_SIZ_L		(sizeof(struct mobile_h))
148#define MOB_H_SBIT	0x0080
149
150#define	GRE_TTL	30
151
152#endif /* _KERNEL */
153
154/*
155 * ioctls needed to manipulate the interface
156 */
157
158#define GRESADDRS	_IOW('i', 101, struct ifreq)
159#define GRESADDRD	_IOW('i', 102, struct ifreq)
160#define GREGADDRS	_IOWR('i', 103, struct ifreq)
161#define GREGADDRD	_IOWR('i', 104, struct ifreq)
162#define GRESPROTO	_IOW('i' , 105, struct ifreq)
163#define GREGPROTO	_IOWR('i', 106, struct ifreq)
164
165#ifdef _KERNEL
166LIST_HEAD(gre_softc_head, gre_softc);
167extern struct gre_softc_head gre_softc_list;
168
169u_int16_t	gre_in_cksum(u_int16_t *, u_int);
170#endif /* _KERNEL */
171
172#endif
173