1/*	$NetBSD: if_gre.h,v 1.13 2003/11/10 08:51:52 wiz Exp $ */
2/*	 $FreeBSD$ */
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 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#ifndef _NET_IF_GRE_H
34#define _NET_IF_GRE_H
35
36#include <sys/ioccom.h>
37#ifdef _KERNEL
38#include <sys/queue.h>
39
40/*
41 * Version of the WCCP, need to be configured manually since
42 * header for version 2 is the same but IP payload is prepended
43 * with additional 4-bytes field.
44 */
45typedef enum {
46	WCCP_V1 = 0,
47	WCCP_V2
48} wccp_ver_t;
49
50struct gre_softc {
51	struct ifnet *sc_ifp;
52	LIST_ENTRY(gre_softc) sc_list;
53	int gre_unit;
54	int gre_flags;
55	u_int	gre_fibnum;	/* use this fib for envelopes */
56	struct in_addr g_src;	/* source address of gre packets */
57	struct in_addr g_dst;	/* destination address of gre packets */
58	struct route route;	/* routing entry that determines, where a
59				   encapsulated packet should go */
60	u_char g_proto;		/* protocol of encapsulator */
61
62	const struct encaptab *encap;	/* encapsulation cookie */
63
64	uint32_t key;		/* key included in outgoing GRE packets */
65				/* zero means none */
66
67	wccp_ver_t wccp_ver;	/* version of the WCCP */
68};
69#define	GRE2IFP(sc)	((sc)->sc_ifp)
70
71
72struct gre_h {
73	u_int16_t flags;	/* GRE flags */
74	u_int16_t ptype;	/* protocol type of payload typically
75				   Ether protocol type*/
76	uint32_t options[0];	/* optional options */
77/*
78 *  from here on: fields are optional, presence indicated by flags
79 *
80	u_int_16 checksum	checksum (one-complements of GRE header
81				and payload
82				Present if (ck_pres | rt_pres == 1).
83				Valid if (ck_pres == 1).
84	u_int_16 offset		offset from start of routing filed to
85				first octet of active SRE (see below).
86				Present if (ck_pres | rt_pres == 1).
87				Valid if (rt_pres == 1).
88	u_int_32 key		inserted by encapsulator e.g. for
89				authentication
90				Present if (key_pres ==1 ).
91	u_int_32 seq_num	Sequence number to allow for packet order
92				Present if (seq_pres ==1 ).
93	struct gre_sre[] routing Routing fileds (see below)
94				Present if (rt_pres == 1)
95 */
96} __packed;
97
98struct greip {
99	struct ip gi_i;
100	struct gre_h  gi_g;
101} __packed;
102
103#define gi_pr		gi_i.ip_p
104#define gi_len		gi_i.ip_len
105#define gi_src		gi_i.ip_src
106#define gi_dst		gi_i.ip_dst
107#define gi_ptype	gi_g.ptype
108#define gi_flags	gi_g.flags
109#define gi_options	gi_g.options
110
111#define GRE_CP		0x8000  /* Checksum Present */
112#define GRE_RP		0x4000  /* Routing Present */
113#define GRE_KP		0x2000  /* Key Present */
114#define GRE_SP		0x1000  /* Sequence Present */
115#define GRE_SS		0x0800	/* Strict Source Route */
116
117/*
118 * CISCO uses special type for GRE tunnel created as part of WCCP
119 * connection, while in fact those packets are just IPv4 encapsulated
120 * into GRE.
121 */
122#define WCCP_PROTOCOL_TYPE	0x883E
123
124/*
125 * gre_sre defines a Source route Entry. These are needed if packets
126 * should be routed over more than one tunnel hop by hop
127 */
128struct gre_sre {
129	u_int16_t sre_family;	/* address family */
130	u_char	sre_offset;	/* offset to first octet of active entry */
131	u_char	sre_length;	/* number of octets in the SRE.
132				   sre_lengthl==0 -> last entry. */
133	u_char	*sre_rtinfo;	/* the routing information */
134};
135
136struct greioctl {
137	int unit;
138	struct in_addr addr;
139};
140
141/* for mobile encaps */
142
143struct mobile_h {
144	u_int16_t proto;		/* protocol and S-bit */
145	u_int16_t hcrc;			/* header checksum */
146	u_int32_t odst;			/* original destination address */
147	u_int32_t osrc;			/* original source addr, if S-bit set */
148} __packed;
149
150struct mobip_h {
151	struct ip	mi;
152	struct mobile_h	mh;
153} __packed;
154
155
156#define MOB_H_SIZ_S		(sizeof(struct mobile_h) - sizeof(u_int32_t))
157#define MOB_H_SIZ_L		(sizeof(struct mobile_h))
158#define MOB_H_SBIT	0x0080
159
160#define	GRE_TTL	30
161
162#endif /* _KERNEL */
163
164/*
165 * ioctls needed to manipulate the interface
166 */
167
168#define GRESADDRS	_IOW('i', 101, struct ifreq)
169#define GRESADDRD	_IOW('i', 102, struct ifreq)
170#define GREGADDRS	_IOWR('i', 103, struct ifreq)
171#define GREGADDRD	_IOWR('i', 104, struct ifreq)
172#define GRESPROTO	_IOW('i' , 105, struct ifreq)
173#define GREGPROTO	_IOWR('i', 106, struct ifreq)
174#define GREGKEY		_IOWR('i', 107, struct ifreq)
175#define GRESKEY		_IOW('i', 108, struct ifreq)
176
177#ifdef _KERNEL
178LIST_HEAD(gre_softc_head, gre_softc);
179extern struct mtx gre_mtx;
180extern struct gre_softc_head gre_softc_list;
181
182u_int16_t	gre_in_cksum(u_int16_t *, u_int);
183#endif /* _KERNEL */
184
185#endif
186