xref: /openbsd/sys/netinet/ip6.h (revision 761f54b6)
1 /*	$OpenBSD: ip6.h,v 1.20 2011/04/05 15:14:59 blambert Exp $	*/
2 /*	$KAME: ip6.h,v 1.45 2003/06/05 04:46:38 keiichi Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1982, 1986, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
62  */
63 
64 #ifndef _NETINET_IP6_H_
65 #define _NETINET_IP6_H_
66 
67 /*
68  * Definition for internet protocol version 6.
69  * RFC 2460
70  */
71 
72 struct ip6_hdr {
73 	union {
74 		struct ip6_hdrctl {
75 			u_int32_t ip6_un1_flow;	/* 20 bits of flow-ID */
76 			u_int16_t ip6_un1_plen;	/* payload length */
77 			u_int8_t  ip6_un1_nxt;	/* next header */
78 			u_int8_t  ip6_un1_hlim;	/* hop limit */
79 		} ip6_un1;
80 		u_int8_t ip6_un2_vfc;	/* 4 bits version, top 4 bits class */
81 	} ip6_ctlun;
82 	struct in6_addr ip6_src;	/* source address */
83 	struct in6_addr ip6_dst;	/* destination address */
84 } __packed;
85 
86 #define ip6_vfc		ip6_ctlun.ip6_un2_vfc
87 #define ip6_flow	ip6_ctlun.ip6_un1.ip6_un1_flow
88 #define ip6_plen	ip6_ctlun.ip6_un1.ip6_un1_plen
89 #define ip6_nxt		ip6_ctlun.ip6_un1.ip6_un1_nxt
90 #define ip6_hlim	ip6_ctlun.ip6_un1.ip6_un1_hlim
91 #define ip6_hops	ip6_ctlun.ip6_un1.ip6_un1_hlim
92 
93 #define IPV6_VERSION		0x60
94 #define IPV6_VERSION_MASK	0xf0
95 
96 #if _BYTE_ORDER == _BIG_ENDIAN
97 #define IPV6_FLOWINFO_MASK	0x0fffffff	/* flow info (28 bits) */
98 #define IPV6_FLOWLABEL_MASK	0x000fffff	/* flow label (20 bits) */
99 #else
100 #if _BYTE_ORDER == _LITTLE_ENDIAN
101 #define IPV6_FLOWINFO_MASK	0xffffff0f	/* flow info (28 bits) */
102 #define IPV6_FLOWLABEL_MASK	0xffff0f00	/* flow label (20 bits) */
103 #endif /* _LITTLE_ENDIAN */
104 #endif
105 #if 1
106 /* ECN bits proposed by Sally Floyd */
107 #define IP6TOS_CE		0x01	/* congestion experienced */
108 #define IP6TOS_ECT		0x02	/* ECN-capable transport */
109 #endif
110 
111 #ifdef _KERNEL
112 /*
113  * for IPv6 pseudo header checksum
114  * XXX nonstandard
115  */
116 struct ip6_hdr_pseudo {
117 	struct in6_addr ip6ph_src;
118 	struct in6_addr ip6ph_dst;
119 	u_int32_t	ip6ph_len;
120 	u_int8_t	ip6ph_zero[3];
121 	u_int8_t	ip6ph_nxt;
122 } __packed;
123 #endif
124 
125 /*
126  * Extension Headers
127  */
128 struct	ip6_ext {
129 	u_int8_t ip6e_nxt;
130 	u_int8_t ip6e_len;
131 } __packed;
132 
133 /* Hop-by-Hop options header */
134 /* XXX should we pad it to force alignment on an 8-byte boundary? */
135 struct ip6_hbh {
136 	u_int8_t ip6h_nxt;	/* next header */
137 	u_int8_t ip6h_len;	/* length in units of 8 octets */
138 	/* followed by options */
139 } __packed;
140 
141 /* Destination options header */
142 /* XXX should we pad it to force alignment on an 8-byte boundary? */
143 struct ip6_dest {
144 	u_int8_t ip6d_nxt;	/* next header */
145 	u_int8_t ip6d_len;	/* length in units of 8 octets */
146 	/* followed by options */
147 } __packed;
148 
149 /* Option types and related macros */
150 #define IP6OPT_PAD1		0x00	/* 00 0 00000 */
151 #define IP6OPT_PADN		0x01	/* 00 0 00001 */
152 #define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
153 #define IP6OPT_NSAP_ADDR	0xC3	/* 11 0 00011 */
154 #define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
155 #define IP6OPT_ROUTER_ALERT	0x05	/* 00 0 00101 (RFC3542, recommended) */
156 
157 #define IP6OPT_RTALERT_LEN	4
158 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
159 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
160 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
161 #define IP6OPT_MINLEN		2
162 
163 #define IP6OPT_TYPE(o)		((o) & 0xC0)
164 #define IP6OPT_TYPE_SKIP	0x00
165 #define IP6OPT_TYPE_DISCARD	0x40
166 #define IP6OPT_TYPE_FORCEICMP	0x80
167 #define IP6OPT_TYPE_ICMP	0xC0
168 
169 #define IP6OPT_MUTABLE		0x20
170 
171 /* IPv6 options: common part */
172 struct ip6_opt {
173 	u_int8_t ip6o_type;
174 	u_int8_t ip6o_len;
175 } __packed;
176 
177 /* Jumbo Payload Option */
178 struct ip6_opt_jumbo {
179 	u_int8_t ip6oj_type;
180 	u_int8_t ip6oj_len;
181 	u_int8_t ip6oj_jumbo_len[4];
182 } __packed;
183 #define IP6OPT_JUMBO_LEN 6
184 
185 /* NSAP Address Option */
186 struct ip6_opt_nsap {
187 	u_int8_t ip6on_type;
188 	u_int8_t ip6on_len;
189 	u_int8_t ip6on_src_nsap_len;
190 	u_int8_t ip6on_dst_nsap_len;
191 	/* followed by source NSAP */
192 	/* followed by destination NSAP */
193 } __packed;
194 
195 /* Tunnel Limit Option */
196 struct ip6_opt_tunnel {
197 	u_int8_t ip6ot_type;
198 	u_int8_t ip6ot_len;
199 	u_int8_t ip6ot_encap_limit;
200 } __packed;
201 
202 /* Router Alert Option */
203 struct ip6_opt_router {
204 	u_int8_t ip6or_type;
205 	u_int8_t ip6or_len;
206 	u_int8_t ip6or_value[2];
207 } __packed;
208 /* Router alert values (in network byte order) */
209 #if _BYTE_ORDER == _BIG_ENDIAN
210 #define IP6_ALERT_MLD	0x0000
211 #define IP6_ALERT_RSVP	0x0001
212 #define IP6_ALERT_AN	0x0002
213 #else
214 #if _BYTE_ORDER == _LITTLE_ENDIAN
215 #define IP6_ALERT_MLD	0x0000
216 #define IP6_ALERT_RSVP	0x0100
217 #define IP6_ALERT_AN	0x0200
218 #endif /* _LITTLE_ENDIAN */
219 #endif
220 
221 /* Routing header */
222 struct ip6_rthdr {
223 	u_int8_t  ip6r_nxt;	/* next header */
224 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
225 	u_int8_t  ip6r_type;	/* routing type */
226 	u_int8_t  ip6r_segleft;	/* segments left */
227 	/* followed by routing type specific data */
228 } __packed;
229 
230 /* Type 0 Routing header */
231 struct ip6_rthdr0 {
232 	u_int8_t  ip6r0_nxt;		/* next header */
233 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
234 	u_int8_t  ip6r0_type;		/* always zero */
235 	u_int8_t  ip6r0_segleft;	/* segments left */
236 	u_int32_t ip6r0_reserved;	/* reserved field */
237 } __packed;
238 
239 /* Fragment header */
240 struct ip6_frag {
241 	u_int8_t  ip6f_nxt;		/* next header */
242 	u_int8_t  ip6f_reserved;	/* reserved field */
243 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
244 	u_int32_t ip6f_ident;		/* identification */
245 } __packed;
246 
247 #if _BYTE_ORDER == _BIG_ENDIAN
248 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
249 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
250 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
251 #else /* _BYTE_ORDER == _LITTLE_ENDIAN */
252 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
253 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
254 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
255 #endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
256 
257 /*
258  * Internet implementation parameters.
259  */
260 #define IPV6_MAXHLIM	255	/* maximum hoplimit */
261 #define IPV6_DEFHLIM	64	/* default hlim */
262 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
263 #define IPV6_HLIMDEC	1	/* subtracted when forwarding */
264 
265 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
266 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
267 
268 #ifdef _KERNEL
269 /*
270  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
271  * "len") is located in single mbuf, on contiguous memory region.
272  * The pointer to the region will be returned to pointer variable "val",
273  * with type "typ".
274  */
275 #define IP6_EXTHDR_GET(val, typ, m, off, len)				\
276 do {									\
277 	struct mbuf *t;							\
278 	int tmp;							\
279 	if ((m)->m_len >= (off) + (len))				\
280 		(val) = (typ)(mtod((m), caddr_t) + (off));		\
281 	else {								\
282 		t = m_pulldown((m), (off), (len), &tmp);		\
283 		if (t) {						\
284 			if (t->m_len < tmp + (len))			\
285 				panic("m_pulldown malfunction");	\
286 			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
287 		} else {						\
288 			(val) = (typ)NULL;				\
289 			(m) = NULL;					\
290 		}							\
291 	}								\
292 } while (/* CONSTCOND */ 0)
293 #endif /* _KERNEL */
294 #endif /* _NETINET_IP6_H_ */
295