1 /*	$NetBSD: ip6.h,v 1.23 2007/12/25 18:33:46 perry 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 
129 struct	ip6_ext {
130 	u_int8_t ip6e_nxt;
131 	u_int8_t ip6e_len;
132 } __packed;
133 
134 /* Hop-by-Hop options header */
135 /* XXX should we pad it to force alignment on an 8-byte boundary? */
136 struct ip6_hbh {
137 	u_int8_t ip6h_nxt;	/* next header */
138 	u_int8_t ip6h_len;	/* length in units of 8 octets */
139 	/* followed by options */
140 } __packed;
141 
142 /* Destination options header */
143 /* XXX should we pad it to force alignment on an 8-byte boundary? */
144 struct ip6_dest {
145 	u_int8_t ip6d_nxt;	/* next header */
146 	u_int8_t ip6d_len;	/* length in units of 8 octets */
147 	/* followed by options */
148 } __packed;
149 
150 /* Option types and related macros */
151 #define IP6OPT_PAD1		0x00	/* 00 0 00000 */
152 #define IP6OPT_PADN		0x01	/* 00 0 00001 */
153 #define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
154 #define IP6OPT_NSAP_ADDR	0xC3	/* 11 0 00011 */
155 #define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
156 #define IP6OPT_RTALERT		0x05	/* 00 0 00101 (KAME definition) */
157 #define IP6OPT_ROUTER_ALERT	0x05	/* (RFC3542 def, recommended) */
158 
159 #define IP6OPT_RTALERT_LEN	4
160 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
161 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
162 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
163 #define IP6OPT_MINLEN		2
164 
165 #define IP6OPT_TYPE(o)		((o) & 0xC0)
166 #define IP6OPT_TYPE_SKIP	0x00
167 #define IP6OPT_TYPE_DISCARD	0x40
168 #define IP6OPT_TYPE_FORCEICMP	0x80
169 #define IP6OPT_TYPE_ICMP	0xC0
170 
171 #define IP6OPT_MUTABLE		0x20
172 
173 /* IPv6 options: common part */
174 struct ip6_opt {
175 	u_int8_t ip6o_type;
176 	u_int8_t ip6o_len;
177 } __packed;
178 
179 /* Jumbo Payload Option */
180 struct ip6_opt_jumbo {
181 	u_int8_t ip6oj_type;
182 	u_int8_t ip6oj_len;
183 	u_int8_t ip6oj_jumbo_len[4];
184 } __packed;
185 #define IP6OPT_JUMBO_LEN 6
186 
187 /* NSAP Address Option */
188 struct ip6_opt_nsap {
189 	u_int8_t ip6on_type;
190 	u_int8_t ip6on_len;
191 	u_int8_t ip6on_src_nsap_len;
192 	u_int8_t ip6on_dst_nsap_len;
193 	/* followed by source NSAP */
194 	/* followed by destination NSAP */
195 } __packed;
196 
197 /* Tunnel Limit Option */
198 struct ip6_opt_tunnel {
199 	u_int8_t ip6ot_type;
200 	u_int8_t ip6ot_len;
201 	u_int8_t ip6ot_encap_limit;
202 } __packed;
203 
204 /* Router Alert Option */
205 struct ip6_opt_router {
206 	u_int8_t ip6or_type;
207 	u_int8_t ip6or_len;
208 	u_int8_t ip6or_value[2];
209 } __packed;
210 /* Router alert values (in network byte order) */
211 #if BYTE_ORDER == BIG_ENDIAN
212 #define IP6_ALERT_MLD	0x0000
213 #define IP6_ALERT_RSVP	0x0001
214 #define IP6_ALERT_AN	0x0002
215 #else
216 #if BYTE_ORDER == LITTLE_ENDIAN
217 #define IP6_ALERT_MLD	0x0000
218 #define IP6_ALERT_RSVP	0x0100
219 #define IP6_ALERT_AN	0x0200
220 #endif /* LITTLE_ENDIAN */
221 #endif
222 
223 /* Routing header */
224 struct ip6_rthdr {
225 	u_int8_t  ip6r_nxt;	/* next header */
226 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
227 	u_int8_t  ip6r_type;	/* routing type */
228 	u_int8_t  ip6r_segleft;	/* segments left */
229 	/* followed by routing type specific data */
230 } __packed;
231 
232 /* Type 0 Routing header */
233 struct ip6_rthdr0 {
234 	u_int8_t  ip6r0_nxt;		/* next header */
235 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
236 	u_int8_t  ip6r0_type;		/* always zero */
237 	u_int8_t  ip6r0_segleft;	/* segments left */
238 	u_int32_t ip6r0_reserved;	/* reserved field */
239 } __packed;
240 
241 /* Fragment header */
242 struct ip6_frag {
243 	u_int8_t  ip6f_nxt;		/* next header */
244 	u_int8_t  ip6f_reserved;	/* reserved field */
245 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
246 	u_int32_t ip6f_ident;		/* identification */
247 } __packed;
248 
249 #if BYTE_ORDER == BIG_ENDIAN
250 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
251 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
252 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
253 #else /* BYTE_ORDER == LITTLE_ENDIAN */
254 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
255 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
256 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
257 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
258 
259 /*
260  * Internet implementation parameters.
261  */
262 #define IPV6_MAXHLIM	255	/* maximum hoplimit */
263 #define IPV6_DEFHLIM	64	/* default hlim */
264 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
265 #define IPV6_HLIMDEC	1	/* subtracted when forwarding */
266 
267 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
268 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
269 
270 #ifdef _KERNEL
271 /*
272  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
273  * "len") is located in single mbuf, on contiguous memory region.
274  * The pointer to the region will be returned to pointer variable "val",
275  * with type "typ".
276  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
277  * very top of mbuf.  GET0 is likely to make memory copy than GET.
278  *
279  * XXX we're now testing this, needs m_pulldown()
280  */
281 #define IP6_EXTHDR_GET(val, typ, m, off, len) \
282 do {									\
283 	struct mbuf *_t;						\
284 	int _tmp;							\
285 	if ((m)->m_len >= (off) + (len))				\
286 		(val) = (typ)(mtod((m), char *) + (off));		\
287 	else {								\
288 		_t = m_pulldown((m), (off), (len), &_tmp);		\
289 		if (_t) {						\
290 			if (_t->m_len < _tmp + (len))			\
291 				panic("m_pulldown malfunction");	\
292 			(val) = (typ)(mtod(_t, char *) + _tmp);	\
293 		} else {						\
294 			(val) = (typ)NULL;				\
295 			(m) = NULL;					\
296 		}							\
297 	}								\
298 } while (/*CONSTCOND*/ 0)
299 
300 #define IP6_EXTHDR_GET0(val, typ, m, off, len) \
301 do {									\
302 	struct mbuf *_t;						\
303 	if ((off) == 0 && (m)->m_len >= len)				\
304 		(val) = (typ)mtod((m), void *);			\
305 	else {								\
306 		_t = m_pulldown((m), (off), (len), NULL);		\
307 		if (_t) {						\
308 			if (_t->m_len < (len))				\
309 				panic("m_pulldown malfunction");	\
310 			(val) = (typ)mtod(_t, void *);			\
311 		} else {						\
312 			(val) = (typ)NULL;				\
313 			(m) = NULL;					\
314 		}							\
315 	}								\
316 } while (/*CONSTCOND*/ 0)
317 #endif /*_KERNEL*/
318 
319 #endif /* !_NETINET_IP6_H_ */
320