xref: /openbsd-src/sys/net/if_gre.h (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*      $OpenBSD: if_gre.h,v 1.4 2001/06/09 06:16:38 angelos Exp $ */
2 /*	$NetBSD: if_gre.h,v 1.5 1999/11/19 20:41:19 thorpej Exp $ */
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 struct gre_softc {
44 	struct ifnet sc_if;
45 	int gre_unit;
46 	int gre_flags;
47 	struct    in_addr g_src;  /* source address of gre packets */
48 	struct    in_addr g_dst;  /* destination address of gre packets */
49 	struct route route;	/* routing entry that determines, where a
50                                    encapsulated packet should go */
51 	u_char g_proto;		/* protocol of encapsulator */
52 };
53 
54 
55 struct gre_h {
56 	u_int16_t flags;	/* GRE flags */
57 	u_int16_t ptype;	/* protocol type of payload typically
58                                Ether protocol type*/
59 /*
60  *  from here on: fields are optional, presence indicated by flags
61  *
62 	u_int_16 checksum	 checksum (one-complements of GRE header
63                              and payload
64                              Present if (ck_pres | rt_pres == 1).
65                              Valid if (ck_pres == 1).
66 	u_int_16 offset			 offset from start of routing filed to
67                              first octet of active SRE (see below).
68                              Present if (ck_pres | rt_pres == 1).
69                              Valid if (rt_pres == 1).
70 	u_int_32 key         inserted by encapsulator e.g. for
71                              authentication
72                              Present if (key_pres ==1 ).
73 	u_int_32 seq_num     Sequence number to allow for packet order
74                              Present if (seq_pres ==1 ).
75 
76     struct gre_sre[] routing Routing fileds (see below)
77                              Present if (rt_pres == 1)
78 */
79 } __attribute__((__packed__));
80 
81 struct greip {
82 	struct ip gi_i;
83 	struct gre_h  gi_g;
84 } __attribute__((__packed__));
85 
86 #define gi_pr           gi_i.ip_p
87 #define gi_len          gi_i.ip_len
88 #define gi_src          gi_i.ip_src
89 #define gi_dst          gi_i.ip_dst
90 #define gi_ptype	gi_g.ptype
91 #define gi_flags	gi_g.flags
92 
93 #define GRE_CP          0x8000  /* Checksum Present */
94 #define GRE_RP          0x4000  /* Routing Present */
95 #define GRE_KP          0x2000  /* Key Present */
96 #define GRE_SP          0x1000  /* Sequence Present */
97 #define GRE_SS		0x0800	/* Strict Source Route */
98 
99 /* gre_sre defines a Source route Entry. These are needed if packets
100  *  should be routed over more than one tunnel hop by hop
101  */
102 
103 struct gre_sre {
104 	u_int16_t sre_family;	/* adress family */
105 	u_char  sre_offset;	/* offset to first octet of active entry */
106 	u_char  sre_length;	/* number of octets in the SRE.
107                                sre_lengthl==0 -> last entry. */
108 	u_char  *sre_rtinfo;	/* the routing information */
109 };
110 
111 struct greioctl {
112 	int unit;
113 	struct    in_addr addr;
114 };
115 
116 /* for mobile encaps */
117 
118 struct mobile_h {
119 	u_int16_t proto;		/* protocol and S-bit */
120 	u_int16_t hcrc;			/* header checksum */
121 	u_int32_t odst;			/* original destination address */
122 	u_int32_t osrc;			/* original source addr, if S-bit set */
123 } __attribute__((__packed__));
124 
125 struct mobip_h {
126 	struct ip       mi;
127 	struct mobile_h mh;
128 } __attribute__((__packed__));
129 
130 
131 #define MOB_H_SIZ_S		(sizeof(struct mobile_h) - sizeof(u_int32_t))
132 #define MOB_H_SIZ_L		(sizeof(struct mobile_h))
133 #define MOB_H_SBIT	0x0080
134 
135 
136 /*
137  * ioctls needed to manipulate the interface
138  */
139 
140 #ifdef _KERNEL
141 extern	struct gre_softc *gre;
142 extern	int ngre;
143 extern  int gre_allow;
144 extern  int ip_mobile_allow;
145 
146 void	greattach __P((int));
147 int     gre_ioctl __P((struct ifnet *, u_long, caddr_t));
148 int     gre_output __P((struct ifnet *, struct mbuf *, struct sockaddr *,
149 	    struct rtentry *rt));
150 u_short	gre_in_cksum(u_short *p, u_int len);
151 #endif /* _KERNEL */
152 #endif /* _NET_IF_GRE_H_ */
153