xref: /freebsd/sys/net/if_gre.h (revision 3157ba21)
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  */
45 typedef enum {
46 	WCCP_V1 = 0,
47 	WCCP_V2
48 } wccp_ver_t;
49 
50 struct 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 	int called;		/* infinite recursion preventer */
65 
66 	uint32_t key;		/* key included in outgoing GRE packets */
67 				/* zero means none */
68 
69 	wccp_ver_t wccp_ver;	/* version of the WCCP */
70 };
71 #define	GRE2IFP(sc)	((sc)->sc_ifp)
72 
73 
74 struct gre_h {
75 	u_int16_t flags;	/* GRE flags */
76 	u_int16_t ptype;	/* protocol type of payload typically
77 				   Ether protocol type*/
78 	uint32_t options[0];	/* optional options */
79 /*
80  *  from here on: fields are optional, presence indicated by flags
81  *
82 	u_int_16 checksum	checksum (one-complements of GRE header
83 				and payload
84 				Present if (ck_pres | rt_pres == 1).
85 				Valid if (ck_pres == 1).
86 	u_int_16 offset		offset from start of routing filed to
87 				first octet of active SRE (see below).
88 				Present if (ck_pres | rt_pres == 1).
89 				Valid if (rt_pres == 1).
90 	u_int_32 key		inserted by encapsulator e.g. for
91 				authentication
92 				Present if (key_pres ==1 ).
93 	u_int_32 seq_num	Sequence number to allow for packet order
94 				Present if (seq_pres ==1 ).
95 	struct gre_sre[] routing Routing fileds (see below)
96 				Present if (rt_pres == 1)
97  */
98 } __packed;
99 
100 struct greip {
101 	struct ip gi_i;
102 	struct gre_h  gi_g;
103 } __packed;
104 
105 #define gi_pr		gi_i.ip_p
106 #define gi_len		gi_i.ip_len
107 #define gi_src		gi_i.ip_src
108 #define gi_dst		gi_i.ip_dst
109 #define gi_ptype	gi_g.ptype
110 #define gi_flags	gi_g.flags
111 #define gi_options	gi_g.options
112 
113 #define GRE_CP		0x8000  /* Checksum Present */
114 #define GRE_RP		0x4000  /* Routing Present */
115 #define GRE_KP		0x2000  /* Key Present */
116 #define GRE_SP		0x1000  /* Sequence Present */
117 #define GRE_SS		0x0800	/* Strict Source Route */
118 
119 /*
120  * CISCO uses special type for GRE tunnel created as part of WCCP
121  * connection, while in fact those packets are just IPv4 encapsulated
122  * into GRE.
123  */
124 #define WCCP_PROTOCOL_TYPE	0x883E
125 
126 /*
127  * gre_sre defines a Source route Entry. These are needed if packets
128  * should be routed over more than one tunnel hop by hop
129  */
130 struct gre_sre {
131 	u_int16_t sre_family;	/* address family */
132 	u_char	sre_offset;	/* offset to first octet of active entry */
133 	u_char	sre_length;	/* number of octets in the SRE.
134 				   sre_lengthl==0 -> last entry. */
135 	u_char	*sre_rtinfo;	/* the routing information */
136 };
137 
138 struct greioctl {
139 	int unit;
140 	struct in_addr addr;
141 };
142 
143 /* for mobile encaps */
144 
145 struct mobile_h {
146 	u_int16_t proto;		/* protocol and S-bit */
147 	u_int16_t hcrc;			/* header checksum */
148 	u_int32_t odst;			/* original destination address */
149 	u_int32_t osrc;			/* original source addr, if S-bit set */
150 } __packed;
151 
152 struct mobip_h {
153 	struct ip	mi;
154 	struct mobile_h	mh;
155 } __packed;
156 
157 
158 #define MOB_H_SIZ_S		(sizeof(struct mobile_h) - sizeof(u_int32_t))
159 #define MOB_H_SIZ_L		(sizeof(struct mobile_h))
160 #define MOB_H_SBIT	0x0080
161 
162 #define	GRE_TTL	30
163 
164 #endif /* _KERNEL */
165 
166 /*
167  * ioctls needed to manipulate the interface
168  */
169 
170 #define GRESADDRS	_IOW('i', 101, struct ifreq)
171 #define GRESADDRD	_IOW('i', 102, struct ifreq)
172 #define GREGADDRS	_IOWR('i', 103, struct ifreq)
173 #define GREGADDRD	_IOWR('i', 104, struct ifreq)
174 #define GRESPROTO	_IOW('i' , 105, struct ifreq)
175 #define GREGPROTO	_IOWR('i', 106, struct ifreq)
176 #define GREGKEY		_IOWR('i', 107, struct ifreq)
177 #define GRESKEY		_IOW('i', 108, struct ifreq)
178 
179 #ifdef _KERNEL
180 LIST_HEAD(gre_softc_head, gre_softc);
181 extern struct mtx gre_mtx;
182 extern struct gre_softc_head gre_softc_list;
183 
184 u_int16_t	gre_in_cksum(u_int16_t *, u_int);
185 #endif /* _KERNEL */
186 
187 #endif
188