xref: /openbsd/sys/net/if_gre.h (revision 17df1aa7)
1 /*      $OpenBSD: if_gre.h,v 1.12 2009/11/21 14:08:14 claudio 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  *
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 struct gre_softc {
37 	struct ifnet sc_if;
38 	LIST_ENTRY(gre_softc) sc_list;
39 	struct    in_addr g_src;  /* source address of gre packets */
40 	struct    in_addr g_dst;  /* destination address of gre packets */
41 	struct route route;	/* routing entry that determines, where a
42                                    encapsulated packet should go */
43 	int gre_unit;
44 	int gre_flags;
45 	u_int  g_rtableid;	/* routing table used for the tunnel */
46 	u_char g_proto;		/* protocol of encapsulator */
47 };
48 
49 
50 struct gre_h {
51 	u_int16_t flags;	/* GRE flags */
52 	u_int16_t ptype;	/* protocol type of payload typically
53                                Ether protocol type*/
54 /*
55  *  from here on: fields are optional, presence indicated by flags
56  *
57 	u_int_16 checksum	 checksum (one-complements of GRE header
58                              and payload
59                              Present if (ck_pres | rt_pres == 1).
60                              Valid if (ck_pres == 1).
61 	u_int_16 offset			 offset from start of routing filed to
62                              first octet of active SRE (see below).
63                              Present if (ck_pres | rt_pres == 1).
64                              Valid if (rt_pres == 1).
65 	u_int_32 key         inserted by encapsulator e.g. for
66                              authentication
67                              Present if (key_pres ==1 ).
68 	u_int_32 seq_num     Sequence number to allow for packet order
69                              Present if (seq_pres ==1 ).
70 
71     struct gre_sre[] routing Routing fileds (see below)
72                              Present if (rt_pres == 1)
73 */
74 } __packed;
75 
76 struct greip {
77 	struct ip gi_i;
78 	struct gre_h  gi_g;
79 } __packed;
80 
81 #define gi_pr           gi_i.ip_p
82 #define gi_len          gi_i.ip_len
83 #define gi_src          gi_i.ip_src
84 #define gi_dst          gi_i.ip_dst
85 #define gi_ptype	gi_g.ptype
86 #define gi_flags	gi_g.flags
87 
88 #define GRE_CP          0x8000  /* Checksum Present */
89 #define GRE_RP          0x4000  /* Routing Present */
90 #define GRE_KP          0x2000  /* Key Present */
91 #define GRE_SP          0x1000  /* Sequence Present */
92 #define GRE_SS		0x0800	/* Strict Source Route */
93 
94 /* gre_sre defines a Source route Entry. These are needed if packets
95  *  should be routed over more than one tunnel hop by hop
96  */
97 
98 struct gre_sre {
99 	u_int16_t sre_family;	/* address family */
100 	u_char  sre_offset;	/* offset to first octet of active entry */
101 	u_char  sre_length;	/* number of octets in the SRE.
102                                sre_lengthl==0 -> last entry. */
103 	u_char  *sre_rtinfo;	/* the routing information */
104 };
105 
106 struct greioctl {
107 	int unit;
108 	struct    in_addr addr;
109 };
110 
111 /* for mobile encaps */
112 
113 struct mobile_h {
114 	u_int16_t proto;		/* protocol and S-bit */
115 	u_int16_t hcrc;			/* header checksum */
116 	u_int32_t odst;			/* original destination address */
117 	u_int32_t osrc;			/* original source addr, if S-bit set */
118 } __packed;
119 
120 struct mobip_h {
121 	struct ip       mi;
122 	struct mobile_h mh;
123 } __packed;
124 
125 
126 #define MOB_H_SIZ_S		(sizeof(struct mobile_h) - sizeof(u_int32_t))
127 #define MOB_H_SIZ_L		(sizeof(struct mobile_h))
128 #define MOB_H_SBIT	0x0080
129 
130 
131 /*
132  * ioctls needed to manipulate the interface
133  */
134 
135 #ifdef _KERNEL
136 extern  LIST_HEAD(gre_softc_head, gre_softc) gre_softc_list;
137 extern  int gre_allow;
138 extern  int gre_wccp;
139 extern  int ip_mobile_allow;
140 
141 void	greattach(int);
142 int     gre_ioctl(struct ifnet *, u_long, caddr_t);
143 int     gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
144 	    struct rtentry *);
145 u_int16_t gre_in_cksum(u_int16_t *, u_int);
146 #endif /* _KERNEL */
147 #endif /* _NET_IF_GRE_H_ */
148